Field of the Invention

The present invention relates to a kinetic energy recovery system wherein the recovered energy is later used to augment vehicle acceleration and to reduce fuel consumption. The system is designed for use in any type of motor vehicle or towed vehicle to partially eliminate the need for a conventional hydraulic, pneumatic or electrical braking system.

Background of the Invention

Vehicle-mounted electrical and hydraulic kinetic energy recovery systems are known for kinetic energy recovery when the vehicle is decelerated by application of the vehicle brakes.

A kinetic energy recovery system (often known simply as KERS or kers) is a system for recovering the kinetic energy of a moving vehicle under braking. The recovered energy is stored in a reservoir (for example, a pressurized gas reservoir, a flywheel or high voltage batteries) for later use to assist in vehicle acceleration. Examples include complex cutting-edge systems used in Formula 1 racing and simple, easy-to-manufacture integrated differential-based systems, such as the Cambridge Passenger/Commercial Vehicle Kinetic Energy Recovery System (CPC- KERS).

The hydraulic systems known in the art are not widely applicable and are only appropriate for installation on motor vehicles equipped with universal joints and differentials and planetary gears. Such systems cannot be mounted on wheels without planetary gears or which have steering knuckles. These hydraulic systems operate together with the conventional brakes of a motor vehicle/towed vehicle and cannot fully recover the available kinetic energy, which is split between the conventional braking system where it is transformed into heat due to friction, and the recovery system. Another disadvantage of these systems involves the high costs associated with modification of the motor vehicle structure to allow installation. Moreover, in some recovery hydraulic systems, the ABS (Anti-Lock Brake System) does not operate at the same time as the recovery hydraulic system, resulting in a loss of kinetic energy under braking conditions.

Some recovery hydraulic systems use pump motors with variable blade extensions. If such a pump is activated in a system for recovering the kinetic energy under braking, the vehicle will not be able to brake smoothly, but will brake irregularly due to the surface variation with which the pump blades operate. More specifically, because the section of the blades acting upon fluid in the pressure chamber changes due to the rotor eccentric position with respect to the stator, pressure fluctuations occur in the system and the braking intensity will be discontinuous. This can cause the vehicle to behave under braking as if the brake drums or disks are out of round. This irregular behavior is sometimes referred to as juddering, and it is undesirable.

Electrical hybrid systems are also known that store energy in storage batteries. The disadvantage of these systems is that, in order to recover the braking energy, more accumulators and an electrical motor are necessary in addition to the thermal engine of the motor vehicle. As a result, the retrofitting or manufacturing costs are significant.

Several documents relating to the state of art which describe known kinetic energy recovery hydraulic systems include: WO2010/098881, WO2006/066156 and WO2006/ 122241. Summary of the Invention

The technical problem solved by the present invention, which eliminates the disadvantages of the above-mentioned approaches, is a kinetic energy recovery system which acts when the vehicle is braking. The system is designed for any type of motor vehicle or towed vehicle. The system can be installed directly on the motor vehicle/towed vehicle without any changes in the structure and components of the motor vehicle/towed vehicle. This is accomplished by installing motor hydro-pumps on the vehicle wheels. Specifically, the rotor of the motor hydro-pumps is inechanically attached to the wheel hub, so that the rotor of the motor hydro-pump becomes integral with the wheel hub. The rotor is not affixed to the planetary gears or universal joint. Under braking, the rotor has a pump role and, under acceleration, a hydraulic engine role. Together with the other system components, the system fully recovers the total kinetic energy under braking of the motor vehicle/towed vehicle and converts the recovered energy fluid to pressure that may be reused, under acceleration, to start the vehicle or for propulsion.

Another technical problem solved by the present invention, in a second embodiment, in addition to kinetic energy recovery under braking, is to provide four-wheel drive on motor vehicles with rear-wheel drive by also sending the recovered motor vehicle power or energy to the non-drive wheels on which the motor hydro-pumps are fitted.

A motor vehicle/towed vehicle, as described herein, includes at least four wheels and a conventional hydraulic, pneumatic or electrical brake system. The kinetic energy recovery system under braking is installed, according to the present invention, on a vehicle by fitting motor hydro-pumps instead of brake disks and calipers for disc brakes, or instead of brake shoes and cylinders for drum brakes, on some of the driving or non- driving wheels. These wheels can be a steering wheel or not. This is regardless of whether the vehicle is four-wheel drive, front-wheel drive or rear-wheel drive or if the vehicle is provided with axles, but at least two wheels of that motor vehicle are without motor hydro-pumps. In this embodiment of the invention, the conventional brake system is not completely eliminated, and it still operates on some wheels (for example, only on the front wheels or only on the rear wheels). But its activation is delayed and it operates only under emergency braking conditions. In this embodiment of the invention, the kinetic energy can be fully recovered, in general, and the wear of the brake pads and brake disks or brake shoes on these wheels is reduced.

According to the present invention, the system can be built based on each particular motor vehicle design, so that, together with the pneumatic, hydraulic or electrical conventional system, partially maintained on the motor vehicle, it provides braking according to applicable safety standards and regulations. Increased performance can be obtained and the improved braking action should not differ from the braking action provided by the conventional system that was initially installed on the vehicle.

According to the invention, the system operates together with ABS; the wheel sensor and the ABS toothed wheel remain unchanged.

In a first embodiment, the kinetic energy recovery system under braking, according to the present invention, eliminates the disadvantages of the former systems when it is installed on any motor vehicle, or towed vehicle attached to a motor vehicle. That motor vehicle is equipped with a carburetor/fuel injection pump, a conventional brake system with a brake pump and brake calipers/cylinders, a direct current battery, a reverse motion contact; and a brake pedal and an acceleration pedal. The novel system comprises hydraulic cylinders, double-circuit solenoid valves, a simple solenoid valve, proportioning solenoid valves, a hydraulic switch, one-way pressure valves, pressure switches, travel pressure switches. A potentiometer and an electric switch work together with motor hydro-pumps connected to a hydraulic distributor through double-circuit solenoid valves and they are connected to a pneumohydraulic tank by the same double-circuit solenoid valves. The tank is linked to the distributor by a connector equipped with a one-way valve, and to the pneumohydiaulic cylinders by connectors equipped with a one-way valve. The above-mentioned distributor communicates with a lower pressure pneumohydraulic cylinder by a connector provided with a one-way valve; and is also connected to a high pressure pneumohydraulic cylinder by another connector provided with a one-way valve. The novel system also includes a fluid-type equilibrator connected to the motor hydro-pumps and to hydraulic accumulators fitted on the motor hydro-pumps. Hydraulic controllers are installed between the brake calipers/cylinders and the brake pump; and a hydraulic regulator is functionally inserted on the acceleration cable between the acceleration pedal and the carburetor/injection pump.

The motor hydro-pump comprises a rotor, fitted in a stator, supported by bearings and guided by pressure bearings. It is closed by a flange attached to the stator. . Blades are fitted on sealing elements, which can slide axially into and from the rotor in pressure chambers located between the rotor, the stator and the flange. The rotor is equipped with fastening holes and a circular recess which communicates at the bottom with oblique passages which continue with longitudinal passages, followed by radial passages which are connected to the four radial blade seats. The seats are positioned at 90 degrees to one another where the above-mentioned blades slide. A circumferential passage is located in the proximity of the circular recess.

Opposite the circular recess, there is another circular recess in which is defined a circumferential passage. In the proximity of the second circular recess, there is another circular recess with annular passages on each of the two faces of the rotor. In order to center the hydro- pump-motor on the vehicle wheel hub, the rotor is equipped with a cored hole, and the circular recesses are limited to the outside by collars. Another circular recess, with a larger diameter than the cored hole, is provided concentrically to it, and it is designed to couple to the handbrake shoes if the motor hydro-pumps are fitted on the rear wheels. The stator has a cylindrical shape and includes on the outside two antipodal inlets and two antipodal outlets, the inlets and outlets being equal in cross-sectional area, and each of them communicates to the inside through a recess. The stator is also equipped with four circular recesses, each with a smaller diameter.

One of the stator recesses is divided into four cylindrical surfaces with a 40-degree center opening, two cylindrical surfaces with a 10-degree center opening, and two cylindrical surfaces with a 90-degree center opening, and equal center radii. The center radii that describe the surfaces with a 40-degree center opening decrease up to the surfaces with a 10-degree center opening, whose radii are equal to those describing the external circumference of the rotor, the sealing elements surfaces and the blade surfaces.

The stator is also equipped with an axial hole created in step, by three circular recesses, designed for the fitting of the rotor and with a tapped hole on an exterior surface. The stator communicates through recesses to passages and to a circumferential passage. Three other tapped holes are provided on the same exterior stator surface. They communicate with a recess through longitudinal passages and radial passages. An annular passage is located between two of the stator recesses, and two fastening tapped holes are positioned on the exterior surface. The flange is equipped with two circular recesses, and an annular passage formed between them. Inside a circular recess, a circumferential passage is positioned which communicates with another circumferential passage on the flange exterior circumference by passages. The flange is also equipped on the outside with a tapped surface, which ends in a sealing circular recess. An axial hole is also defined on the same flange; it consists of three recesses that increase in diameter.

The blades, positioned at 90 degrees one from another in the rotor radial recesses, comprise two arms each, equipped with cylindrical recesses and ending with a base. Coiled springs are positioned in the cylindrical recess, supported by the above-mentioned bases, while the arms are joined to a cylindrical piston with two sealing circumferential passages and a rounded edge rectangular piston whose cross-section shape allows it to slide over the sealing element. The sealing element is equipped with a rectangular recess that matches the shape of the rectangular piston of the blade, and it has a sealing passage and fastening holes for fastening on the exterior surface of the rotor in seats. The exterior surface of the sealing element is defined by the same radius that generates the rotor external circumference.

Two pressure chambers are formed in the motor hydro-pump, which are equal and antipodal. They are limited by the stator and the rotor exterior surface, and they are closed by the flange. The interior surfaces of the pressure chambers are defined by the rotor exterior surface. Their exterior surfaces are defined by the surfaces with 10-degree, 40-degree and 90- degree center openings. The blades slide, in a controlled way, in the pressure chambers under braking conditions controlled by the brake pedal through the brake pump that controls a hydraulic cylinder linked by a connector to the tapped holes of the motor hydro-pumps. Upon acceleration, the blades are controlled by the acceleration pedal through the fluid-type equilibrator which receives the command from the potentiometer through the electric switch. The blades can slide out to their maximum travel in the pressure chambers formed between the rotor, the stator and the flange along the surfaces with a 90-degree opening. The maximum surface a blade can act with is equal to the surface of an inlet or outlet. The motor hydro-pumps can be fitted on the wheels of the motor vehicle or towed vehicle so as to replace the brake pulleys and calipers on the motor vehicles equipped with disk brakes. Each rotor is coupled to the vehicle wheel hub through the fastening holes, so that the rotor becomes integral with the wheel hub. The stator is coupled with the caliper plate through the tapped fastening holes. The motor hydro- pumps can be fitted on the wheels of the motor vehicle or towed vehicle, replacing the brake shoes and brake cylinders for vehicles equipped with drum brakes, by coupling the rotor to the vehicle wheel hub through the fastening holes. The stators are fastened on the brake shoe plates and, through an intermediary flange, they are fastened on the drums by corresponding holes. The intermediary flange also includes additional holes which match the rotor fastening holes. Thus, each rotor is centered on the wheel hub by an axial hole matching the rotor cored hole.

The hydraulic distributor comprises a tubular body, equipped with three pairs of tapped holes, situated diagonally opposite to one another, so that each pair communicates by openings decreasing in diameter, made inside the above-mentioned tubular body. The tubular body is also equipped with an axial tapped hole and a radial tapped hole; a piston slides inside the tubular body. The piston has a smaller diameter at its ends and, in the middle, it includes circumferential passages. The first passage communicates with the holes that match the first pair of tapped holes, the second passage communicates with the holes that match the second pair of tapped holes, and the third passage communicates with the holes that match the third pair of tapped holes. When the piston slides inside the hydraulic distributor, only two of the circumferential passages can confront and close on the matching hole at the same time. Thus the sum of the passage surfaces obtained by obstruction is equal to the surface of the smaller diameter holes. The piston also has circumferential sealing passages and, at its end, the part with smaller diameter is fitted inside a coiled spring. The piston slides in an axial hole located at the end of the tubular body.

The pneumohydraulic tank is cylindrical and comprises a metallic cylinder, closed with hollow hemispheres at each end. An axle is attached to these hemispheres, on which slides a piston with two circumferential sealing passages. The piston is pressed on a hub that also has sealing passages. The piston divides the tank into two chambers for hydraulic fluid and pressurized gas, respectively. The pneumohydraulic cylinders have a build similar to the tank.

The fluid-type equilibrator comprises an electromagnet connected to a tubular body which includes a radial tapped hole and an axial bore in which a piston, retained by a coiled spring, slides. Both the tubular body and the piston include a circumferential sealing passage while the body is closed, at the opposite end of the electromagnet, with a cap fitted with a depressurization hole. The hydraulic accumulators are mounted in two of the stator tapped holes and have a cylindrical shape, consisting of a tubular body threaded on the outside, which is closed by a tubular body threaded on the inside. Inside the body threaded on the outside, slides a piston, whose rod penetrates an axial hole inside the threaded body. It is retained by a coiled spring and is fitted with a circumferential sealing passage. The outside threaded body is also equipped with an outside threaded fitting. The hydraulic controllers each comprises a tubular body closed at its ends with two cylindrical bodies and fitted with a piston inside. The piston has an axial bore through which it slides along a piston with rod, which it can actuate, retained by a coiled spring. The tubular body includes an axial hole in which the piston with axial bore slides and another axial hole in which the piston with rod slides. The axial holes have different diameters and are situated at each end of the tubular body, being limited inside by a collar, which does not allow the piston with rod to enter the axial hole in which the axial bore piston slides. The same tubular body includes a longitudinal passage, which communicates at one end with the hole in which the axial bore piston slides through a hole communicating with a circumferential passage. That passage communicates with a longitudinal passage, passages of the axial bore piston and, at the other end, with the hole in which the piston with rod slides through another hole. The pistons are each fitted with a circumferential sealing passage. Between the axial bore piston and a cylindrical body, inside the tubular body, a spacer is positioned in the tubular body, in the circumferential passage of the cylindrical body. In addition, the cylindrical bodies are each fitted with a tapped hole and a circumferential sealing passage. The hydraulic acceleration regulator comprises of a tubular body fitted with an axial tapped hole and a circumferential sealing passage and, inside the tubular body, slides a rod pressed by a coiled spring. At the external end of the rod there is a collet, and the tubular body is also fitted with a collet.

In a second embodiment, the inventive kinetic energy recovery system under braking is installed on a rear-drive motor vehicle, in order to recover the kinetic energy under braking, but the system also provides four-wheel drive, and it includes the same components as the first embodiment. The motor hydro pumps are installed on the non-drive wheels of the motor vehicle. The system also includes another motor hydro-pump with a similar build to the hydro- pumps-motor on the wheels. This additional motor hydro-pump is installed between the gearbox flange and the cardan drive (a drive shaft having universal joints at each end) which sends the movement to the rear wheels by the fastening holes of the rotor, which becomes integral with the cardan drive and the gearbox flange. The stator may be mechanically attached to a crossbar fitted between the motor vehicle side rails or to its frame. The same motor hydro-pump is linked through a double-circuit solenoid valve and a connector with the pneumohydraulic tank, the double-circuit solenoid valve being also linked using another connector with the high pressure pneumohydraulic cylinder. Two hydraulic accumulators are located on the motor hydro-pump, which is similar to the hydraulic accumulators in the first embodiment of the invention. In this embodiment, in addition to the previously listed components, the system also includes a fluid- type equilibrator, similar to the fluid-type equilibrator in the first embodiment, which is attached to the motor hydro-pump by a connector, a one-way valve mounted on the connector through which the double-circuit solenoid valve communicates with the pneumohydraulic cylinder. A button is connected to the electric switch, and a solenoid valve is mounted on the connector of the acceleration regulator.

The present invention has a number of benefits and advantages including: the conventional motor vehicle braking system is partially eliminated without eliminating the ABS (anti-lock brake system), by replacing the brake disks and calipers with pumps-motor or installing them inside the drums to replace the brake shoes and cylinders;

the maintenance costs and the costs relating to replacement of the brake disks, brake cylinders, calipers and brake pads/shoes are eliminated; the invention can be installed on any type of motor vehicle without making changes to the vehicle structure, and so the system field of application is broad;

the invention can provide four-wheel drive if mounted on a rear-wheel drive motor vehicle;

the intarder is eliminated in heavy-duty vehicles;

the kinetic energy under braking is fully recovered and used in the acceleration of the motor vehicle, thus fuel consumption in city driving is reduced to the rate of the highway consumption;

the production costs are low due to the simple construction and small dimensions of the parts; and

as an environmental factor, the low fuel consumption leads to a reduction in exhaust emissions.

Brief Description of the Drawings

Two representative embodiments of the present invention are described herein in connection with Figures 1 to 37, in which:

Figure 1 is an electrohydraulic schematic of the kinetic energy recovery system under braking, in a first embodiment, the direction on the inlet and outlet connectors of the motor hydro pumps being represented for forward movement;

Figure 2 is a front view of the motor hydro-pump;

Figure 3 is a cross-sectional view through the motor hydro-pump shown in Figure 2; Figure 4 is a front view of the motor hydro-pump shown in Figure 2, rotated at 90 degrees; Figure 5 is a cross-sectional view of the motor hydro-pump shown in Figure 4;

Figure 6 is a cross-sectional view through the motor hydro-pump shown in Figure 3;

Figure 7 is a front view of the motor hydro-pump rotor;

Figure 8 is a cross-sectional view through the rotor shown in Figure 7;

Figure 9 is a cross-sectional view through the motor hydro-pump stator;

Figure 10 is a cross-sectional view through the motor hydro-pump stator;

Figure 11 is a front view of the motor hydro-pump flange;

Figure 12 is a cross-sectional view through the flange represented in Figure 11;

Figure 13 is an enlarged view VI of the flange shown in Figure 12;

Figure 14 is a front view of the motor hydro-pump rotor blade;

Figure 15 is an isometric view of the motor hydro-pump rotor blade;

Figure 16 is an isometric view of the blade, provided with coil springs;

Figure 17 is a top view of the rotor blade sealing element;

Figure 18 is a cross-sectional view of the sealing element shown in Figure 17;

Figure 19 is a side view of the motor hydro-pump rotor;

Figure 20 is a cross-sectional view through the rotor shown in Figure 19, where a blade is also mounted, as represented in Figure 14, attached to a sealing element in Figure 18;

Figure 21 is an isometric view of the motor hydro-pump rotor;

Figure 22 is a cross-sectional view through the distributor shown in Figure 1 ;

Figure 23 is a cross-sectional view through the hydraulic cylinders shown in Figure 1 ; Figure 24 is a cross-sectional view through the tank and cylinders shown in Figure 1; Figure 25 is a cross-sectional view through the fluid-type equilibrator shown in Figure 1 ; Figure 26 is a cross-sectional view section through the hydraulic accumulators shown in Figure 1;

Figure 27 is a partial sectional view of the motor hydro-pump shown in Figure 5, on which the hydraulic accumulator is fitted;

Figure 28 is a cross-sectional view through the hydraulic controller shown in Figure 1 ;

Figure 29 is a cross-sectional view through the acceleration hydraulic regulator shown in Figure 1 ;

Figure 30 is an isometric view of the motor hydro-pump;

Figure 31 is a front view of the motor hydro-pump to which an intermediary flange is attached;

Figure 32 is a cross-sectional view of the motor hydro pump assembled with the intermediary flange shown in Figure 31 ;

Figure 33 is an admission exhaust diagram under braking, with forward movement, of the motor hydro-pump through the double-circuit solenoid valve, shown in Figure 1 ;

Figure 34 is an admission/exhaust diagram under acceleration, in forward movement, of the motor hydro-pump through the double-circuit solenoid valve;

Figure 35 is an admission/exhaust diagram under braking, in reverse motion, of the motor hydro-pump through the double-circuit solenoid valve;

Figure 36 is an admission/exhaust diagram under braking, in reverse motion, of the motor hydro-pump through the double-circuit solenoid valve; and

Figure 37 is an electrohydraulic diagram of the kinetic energy recovery system under braking, according to a second embodiment of the present invention; Detailed Description of the Invention

A detailed description of the kinetic energy recovery system under braking, according to the invention, a first embodiment is provided below.

In this first embodiment, the kinetic energy recovery system under braking according to the present invention installed on a motor vehicle or towed vehicle fitted with a conventional braking system, comprises actuators shown in Figure 1, as follows: motor hydro-pumps A, connected to a hydraulic distributor B and hydraulic cylinders CI and C2, which communicate with a pneumohydraulic tank D and pneumohydraulic cylinders E and F, a fluid-type equilibrator G, hydraulic accumulators H, hydraulic controllers J, and a hydraulic regulator K.

In addition, according to the invention, the system comprises of command and control elements, represented in Figure 1 : double-circuit solenoid valves 1 , a simple circuit solenoid valve 2, proportioning solenoid valves 3 and 4, a hydraulic switch 5, one-way pressure valves 6, 7, 8, 9, and 10, pressure switches 11 and 12, travel switches 13 and 14, a potentiometer 15 and an electric switch L.

The system, according to the invention, is installed on a motor vehicle fitted with a direct current battery 16, a brake pump 17, a carburetor/injection pump 18, brake calipers/cylinders 19, and the well-known brake pedal 20, as well as an acceleration pedal 21, and a reverse motion contact 22 (reverse light).

If the system, according to the invention, is installed on a towed vehicle, the actuators and the controls are the same. However, they will communicate or will be connected to the brake pump 17 and the battery 16 of the motor vehicle hauling the vehicle, and will be controlled by the brake pedal 20, and the acceleration pedal 21 of the motor vehicle, and for the reverse motion, the reverse motion contact 22 (reverse light) of the vehicle will also be connected to the electric switch L, thus keeping the same configuration as in Figure 1.

The motor hydro-pump A shown in Figures 2-6 includes a rotor 23, mounted in a stator 24, and closed by a flange 25 and several blades 26, which axially slide in and out from the rotor 23 and are fastened to sealing elements 27.

The rotor 23 shown in Figure 8 has a cylindrical shape and is fitted with fastening holes 28 with screws on the vehicle wheel hub. The rotor 23 (Figure 8) is fitted with a recess 29, which communicates at the bottom with several oblique passages 30, continued by longitudinal passages 31, followed by radial passages 32, which are connected to the four radial seats 33, positioned at 90 degrees, in which the blades 26 slide. In the proximity of the recess 29 (Figure 8), there is a circumferential passage 34, and on the opposite side of the recess 29, another recess 35 is made and a communicating circumferential passage 36. In the proximity of the recess 35, there is another recess 37. On each of the two faces of the rotor 23, an annular passage 38 and 39 is present. In order to center the motor hydro-pump A on the motor vehicle wheel hub, the rotor 23 is fitted with a center hole 40. Another recess 40a is provided, with a larger diameter and concentric with the center hole 40; on its surface, the handbrake shoes are fitted if the motor hydro pumps A are installed on the vehicle rear wheels. The recesses 29 and 35 are limited to the outside by collars 41 and 42, respectively.

A blade 26 (Figs. 14-15) slides in each of the four radial seats 33 (Fig. 20). As shown in

Figs. 14-16, the blade 26 includes two arms 43, equipped with cylindrical recesses 44 and including a base 45. In each cylindrical recess 44, a coiled spring 46 (Fig. 16) is supported by the base 45. The arms 43 are integral with a cylindrical piston 47, fitted with two circumferential passages 48, designed to accommodate several sealing O-rings (not shown). The arms 43 and the cylindrical piston 47 are also integral with a rectangular piston 49, with rounded edges, whose cross-sectional shape must allow its gliding through a sealing element 27, namely by a rectangular recess 50, that matches in shape the rectangular piston 49, and provided with a passage 51, designed for sealing. The sealing element 27 (Figs. 17-18) is fitted with fastening holes 52 and is fastened with non-positioned screws on surface 53 of the rotor 23 (Figs. 19, 20 and 21) described by its external circumference, in the recesses 54 fitted with holes 54a that match the holes 52. The external surface 55 of the sealing element 27 and surface 56 of the rectangular pistons 49 of blades 26 are described by the same radius that describes the surface 53 which matches the external circumference of the rotor 23. Surface 56a (Fig. 15) of a blade 26 is the actuation surface.

The stator 24 (Figs. 9-10) has an outer cylindrical shape and includes on the outside two antipodal openings 57 and two openings 58, which are also antipodal, openings 57 and openings 58 being inlet or exhaust openings, equal in area, and each communicating inside with a recess 59. As shown in Fig. 9 and elsewhere, the stator 24 is fitted with several recesses, with decreasing diameter, as follows: a first threaded recess 60 inside, followed by another recess 61, continued by recess 62. There is another recess 63 and another recess 64 clearance with decreasing diameters. The circumference of recess 62 is divided into four surfaces 65 matching recesses 59, two surfaces 66 and two surfaces 67. The center opening of the cylindrical surfaces 65 is 40 degrees as shown in Fig. 6, and the center opening of the cylindrical surfaces 66, located between two neighboring recesses 59, is 10 degrees, and the center opening of the cylindrical surfaces 67 is 90 degrees.

The center radii describing the cylindrical surfaces 67 are equal but, starting with the cylindrical surfaces 67, the center radii describing the cylindrical surfaces 65 off the recesses 59, decrease up to the cylindrical surfaces 66, having the same radius as surface 53 of the rotor 23, surface 55 of the sealing element 27 and surface 56 of the blades 26.

The stator 24 has another axial hole consisting of recesses 68, 69 and 70, (Figs. 9 and 10) designed for the assembling of the rotor 23. In addition, the stator is fitted with a tapped hole 71, made on an external surface 72, which communicates with recess 61, through passages 73, 74, 75 and 76 and also communicates with recess 63 through passages 73, 74 and finally through the circumferential passage 77. On the same surface 72, there is a tapped hole 78 and two tapped holes 79 (Fig. 5), all communicating with recess 70 through some longitudinal passages 80 and some radial passages 81. An annular passage is located between recesses 63 and 64. On the same surface 72, there are two tapped holes 83 (Fig. 30) coupled with the plate of the brake calipers or shoes on the motor vehicle wheel, for vehicles equipped with disk brakes or vehicles equipped with drum brakes, respectively.

A circular recess 84 and a recess 85 are included in the flange 25 (Figs. 11-13); an annular passage 86 is formed between them and a circumferential passage 87 is included inside recess 85. The circumferential passage 87 communicates through passages 88, 89 and 90 with another circumferential passage 91, located on the external circumference of flange 25. The flange 25 is fitted, on the outside, with a threaded surface 92 that ends in a circular recess 93, designed for a sealing, non-positioned O-ring. The flange 25 is also fitted with an axial hole consisting of three recesses 94, 95 and 96.

Upon insertion of blades 26 in the radial seats 33 of the rotor 23 (Fig. 20), the cylindrical pistons 47 of the blades 26 enter the radial passages 32 and, after fastening the sealing elements 27 into the seats 54, the assembly thus obtained is assembled with the stator 24. On this assembly, the collar 41 of the rotor 23 enters recess 64 of the stator 24.

Upon assembly of the rotor 23 into the stator 24 (Fig. 3), a bearing 97 is mounted, supporting the rotor 23, secured by a fuse 98 and sealed by an oil retainer ring 99, which seals the circumferential passage 100, formed between the recess 70 and the interior surface of the circular recess 29, which thus makes the connection between the oblique passages 30 and the radial passages 81. The bearing 97 and the fuse 98 are closed to the exterior of the motor hydro- pump A by a non-positioned expansion stuffing box.

Within the same assembly, between collar 41 of the rotor 23 and recess 64 of the stator 24, a seat is created, to accommodate an oil retainer ring 101, while between the annular passage 38 of the rotor 23 and the annular passage 82 of the stator 24, a pressure bearing 102 is positioned.

Once this assembly is completed (Fig. 3) between the rotor 23 and the stator 24, the flange 25 is connected with the stator 24 through the threaded surface 92 and the threaded recess 60, respectively. Thus, the collar 42 of the rotor 23 enters the recess 84 of the flange 25, creating a seat for an oil retainer ring 103 (Fig. 3). In the same assembly, a bearing 104 is included supporting the rotor 23, secured by a fuse 105 mounted in the space remained between recess 94 of the flange 25 and recess 35 of the rotor 23 (Fig. 8). This space is closed by an expansion stuffing box (not shown), while between the annular passage 86 of the flange 25 and the annular passage 39 of the rotor 23, a pressure bearing 106 is placed (Fig. 3). The pressure bearings 102 and 106 guide the rotor 23 inside the joint assembly comprising the stator 24 and the flange 25.

During completion of this assembly, between recess 62 of the stator 24, the exterior surface 53 of the rotor 23 and the flange 25, two pressure chambers 107 (Figs. 3 and 6) are created, limited by the rotor 23 and surface 66 of the stator 24, where the blades 26 enter during operation. The blades 26 can slide at maximum travel speed in the pressure chambers 107 along surface 67; and the maximum surface 56a, with which a blade 26 is running, is equal to the surface of an opening 57 or opening 58.

The hydraulic distributor B, as previously referenced and represented in Figure 22, comprises a tubular body 108, fitted with several antipodal pairs of tapped holes 109 and 110, 111 and 1 12, 113 and 1 14, located so that the hole 109 communicates with the hole 1 10 through the openings 115 and the hole 1 11 communicates with the hole 112 through the openings 116, respectively. The hole 1 13 communicates with the hole 114 through the openings 117. These openings have decreasing diameters and are made inside the above-mentioned tubular body 108. At the end towards the solenoid valve 2, the tubular body 108 is fitted with an axial tapped hole 1 18, and a radial tapped hole 119. Inside the tubular body 108, a piston 120 slides, whose ends, are smaller in diameter and, in the middle, it includes circumferential passages 121, 122 and 123. Passage 121 can communicate with the openings 115, passage 122 can communicate with the openings 1 16, and passage 123 can communicate with the openings 1 17. When the openings 1 15 are obstructed by the circumferential passage 121 and the openings 116 are obstructed by the circumferential passage 122, the sum of the passage surfaces obtained by obstruction is equal to the surface of the openings 116; and when the openings 116 are obstructed by the circumferential passage 122 and the openings 1 17 are obstructed by the circumferential passage 123, the sum of the passage surfaces obtained by obstruction is equal to the surface of the openings 1 17. On the same piston 120, sealing circumferential passages 124, 125, 126, 127 and 128 are made, designed for a non-positioned sealing. At the free end of the piston 120, the part with a smaller diameter is inside a coiled spring 129 and it slides through the hole 130, which is at the end of the tubular body 108.

The hydraulic cylinder CI represented in Figure 23 comprises an exterior cylindrical body 131, fitted with an internal thread, in which a cylindrical body 132 is assembled, the body 131 being fitted with a threaded opening 133. The cylindrical body 132 is provided with a threaded opening 134. These openings 133 and 134 are used to connect the hydraulic cylinder C to the electrohydraulic system diagrammed in Figure 1. A piston 135 slides inside the bodies 131 and 132. The piston is fitted with circumferential passages 136 and 137, designed for the non- positioned joints.

The structure of the hydraulic cylinder C2 is identical with the structure of the hydraulic cylinder CI .

The pneumohydraulic tank D represented in Figure 24 has a cylindrical shape and comprises a metallic cylinder 138, closed at its ends with hemispheres. An axle or guide rod 139 is attached to these hemispheres, on which a piston 140 slides, fitted with two sealing circumferential passages 141. The axle 139 or guide rod also strengthens the resistance of the tank D under pressure. The piston 140 is pressed on a hub 142, which is also fitted with passages 143, containing non-positinned seals. The piston 140 divides the tank D into two chambers filled with hydraulic fluid and pressurized gas, respectively. The hydraulic fluid in tank D will never be fully evacuated. A fluid volume at least equal to the volume of a hemisphere will remain inside, due to the planar shape of the hub 142. The pneumohydraulic tank D is under low pressure and has a greater internal volume than the sum of volumes in the cylinders E and F.

The pneumohydraulic cylinders E and F are identical in terms of construction to the tank D, explained above. The cylinders E and F are high pressure cylinders, cylinder E having a lower pressure and a higher volume than cylinder F; both cylinder E and cylinder F can provide braking until the motor vehicle stops from the maximum speed it can reach, but in different braking distances. Both tank D and cylinders E and F include connection openings, not shown.

The fluid-type equilibrator G represented in Figure 25 comprises a tubular electromagnet 144, attached to a tubular body 145 with non-positioned screws, which has a radial tapped hole 146 and an axial bore 147 where a piston 148 slides, retained by a coiled spring 149. The body 145 as well as the piston 148 are fitted with a sealing circumferential passage 150 and 151. The body 145 is closed at the end opposite to the electromagnet 144 with a cap 152, fitted with a depressurization opening 153.

The hydraulic accumulators H represented in Figure 26 have a cylindrical shape, and consist of a tubular body 154, threaded on the outside and closed by a tubular body 155, threaded on the inside. Inside the body 154, a piston 156 slides, its rod entering an axial hole 157 of the body 155, retained by a coiled spring 158 and fitted with a sealing circumferential passage 159. The body 154 is equipped with a threaded fitting 160 on the outside used to mount the hydraulic accumulator H in the tapped holes 79 of the stator 24, represented in Figure 27.

The hydraulic controllers J represented in Figure 28 comprise a tubular body 161, closed at its ends with two cylindrical bodies 162 and 163. A piston 164 is fitted with an axial bore 165 through which slides a piston 166 that it can actuate. The piston 166 is retained by a coil spring 167. The body 161 is fitted with an axial hole 168 where the piston 164 slides, and an axial hole 169 where the piston 166 slides; the holes 168 and 169 have different diameters and are positioned each at one end of the body 161, being limited inside by a collar 170, which does not allow the piston 166 to enter the axial hole 168. The body 161 is also fitted with a longitudinal passage 171, which communicates at one end with the hole 168 by an opening 172, continued with a circumferential passage 173, which communicates with a longitudinal passage 174, passages 173 and 174 of the piston 164, when the piston 164 does not compress the spring 167. At the other end, the passage 171 communicates with the hole 169 by an opening 175. The pistons 164 and 166 are provided each with a sealing circumferential passage 176 and 177. Between the piston 164 and the body 162, inside the body 161, there is a spacer 178, fastened in the circumferential passage 179 of the body 162. The bodies 162 and 163 are each equipped with a tapped hole 180 and a circumferential passage 181, and with a tapped hole 182 and a circumferential passage 183, which are sealing circumferential passages. The hydraulic controllers J are mounted on the wheels on which the motor hydro pumps A are not installed at locations between the brake pump circuits 17 and the wheel brake calipers/cylinders 19, so as to regulate the pressure in the brake calipers/cylinders 19. The acceleration hydraulic regulator K represented in Figure 29 comprises a tubular body 184, fitted with a tapped axial hole 185 and with a sealing circumferential passage 186. A rod 187, pressed by a coiled spring 188, slides inside the tubular body 184. At the external end of the rod 187, is a collet 189; and the tubular body 184 is fitted with another collet 190. The regulator K is interposed on the acceleration cable using the collets 189 and 190, segregating the acceleration cable into two parts, one between the ring 189 and the carburetor/injection pump 18, and the other between the ring 190 and the acceleration pedal 21.

The motor hydro-pumps A may be installed on two of the wheels of the motor vehicle replacing the braking disks and calipers for motor vehicles equipped with disk brakes. The motor hydro-pumps are fastened through the tapped holes 83 (Fig. 30) of the stator 24 on the plate of the motor vehicle wheel calipers. Through the fastening holes 28 (Fig. 7), the rotor 23 is fastened with studs on the wheel hub, becoming integral with it.

In addition, these motor hydro-pumps A may be installed in place of the brake shoes on a brake shoe mount for vehicles equipped with drum brakes, using the tapped holes 83 of the stator 24. A intermediary flange 191 (Figs. 31-32) fastens a motor hydro-pump on the drum through the holes 192. The intermediary flange 191 shown in Figure 32 also includes several holes 193 that match the fastening holes 28 of the rotor 23. Thus, the intermediary flange 191 becomes integral with the rotor 23 and is centered on the hub by the axial hole 193a, which matches the center hole 40 of the rotor 23.

When providing a KER system for a four-wheel vehicle, it is optimal for the motor hydro-pumps A to be installed on two of its wheels so that the kinetic energy can be fully recovered, without any changes to the vehicle or the size of its wheels. In addition, the motor hydro-pumps A may be installed on one or all the wheels of a motor vehicle. If installed on two wheels of a motor vehicle, upon the implementation of the system, the brake calipers/cylinders 19 also remain on the vehicle; due to the hydraulic controllers J, they will work only in emergency braking, thus increasing the safety of the kinetic energy recovery system under braking, installed on the car, even in case of a partial brake system failure.

The motor hydro-pumps A are hydraulically linked by connectors 194 linked to the openings 57 and by connectors 195 linked to the openings 58, each to a double-circuit solenoid valve 1, consisting of two electrically driven double-circuit valves 196 and 197, which switch alternatively the hydraulic circuits 198 and 199, and respectively the circuits 200, 201, represented in Figure 33. The valve 196 communicates with the pneumohydraulic tank D by the connector 202, while the valve 197 communicates with the pneumohydraulic cylinders E and F by the connector 203 (Figs. 1 and 33). At the tapped holes 78 (Fig. 9) of the motor hydro-pumps A, they are hydraulically connected with the hydraulic cylinder C2 and the fluid-type equilibrator G by connectors 204 linked with a connector 205, and, at the holes 71, connectors 206 are linked to the connector 202. The hydraulic/pneumatic circuits 207 and 208 of the brake pump 17, which match the wheels equipped with the motor hydro-pumps A, are connected to the threaded openings 134 of the hydraulic cylinders CI and C2. The opening 133 of the cylinder CI is connected by a connector 209 with the solenoid valve 2, which is connected to the distributor B (Fig- 1).

The double-circuit solenoid valves 1 communicate with the distributor B by a connector 210 and with the regulator K by another connector 211. A connector 212 is linked at the tapped hole 110 of the distributor as well as the valve 6, which communicates with a connector 213 through which the distributor B communicates with the cylinder E. At the tapped hole 1 12 of the distributor B, a connector 215 is linked, which communicates with the valve 7 that is linked with another connector 216 and communicates directly with the cylinder F, and, at the tapped hole 114 of the distributor B, a connector 217 is linked, as well as the valve 8, which communicates directly with the tank D. The cylinder F is also linked to the tank D by a connector 218 fitted with a valve 10 and to the cylinder E by a connector 214 with a valve 9. The cylinder E communicates with the proportioning solenoid valve 4 by the connector 213, connected to a connector 219 of the proportioning solenoid valve 4. The cylinder F communicates with the proportioning solenoid valve 3 by the connector 216 linked to a connector 220. The solenoid valves 3 and 4 communicate with the solenoid valves 1 by a connector 221 linked with the connector 203. The hydraulic controllers J are connected to the other two hydraulic/pneumatic circuits 222 of the brake pump 17 which are interposed between the brake pump 17 and the brake calipers/cylinders 19. A travel switch 13 is mechanically connected to the brake pedal and a travel switch 14 is mechanically connected to the acceleration pedal as well as to a potentiometer 15. The hydraulic regulator K is interposed on the cable, between the acceleration pedal 21 and the carburetor/injection pump 18. The electric switch L is electrically connected to a battery 16, mounted on the motor vehicle.

The system elements are electrically connected to the electric switch L by electric circuits. The switch 13 operates through the circuit 223, the switch 14 operates through the circuit 224, the potentiometer 15 through the circuit 225, and the electromagnet 144 operates the fluid-type equilibrator G through the circuit 226. The solenoid valves 1 operate through the circuits 227, and the solenoid valve 2 operates through the circuit 228. The hydraulic switch 5 operates through the circuit 229, and the proportioning solenoid valves 3 and 4 operates through the circuits 230, and 231, respectively. The pressure switches 1 1 and 12 operate through the circuits 232 and 233, and the reverse motion contact 22 operates through the circuit 234.

The operation of the kinetic energy recovery system under braking in a first embodiment is described below using, as an example, a system-equipped four-wheel motor vehicle.

If the vehicle is equipped with a kinetic energy recovery system under braking, according to the invention, and if the vehicle is running, the rotors 23 of the motor hydro-pumps A exhibit a rotational movement, being integral with the hub of the wheels upon which they are mounted. The blades 26 (Fig. 14) are not activated, being withdrawn in the radial seats 33 (Fig. 6) of the rotors 23. When the driver uses the brake pedal 20, the travel switch 13 sends current through the electric switch L to the solenoid valve 2, which opens the circuit to the distributor B. At the same time, when pressing the brake pedal 20, the brake fluid or the pressurized air from the brake pump 17 act through the hydraulic/ pneumatic circuits 222 to each wheel not equipped with the motor hydro-pumps A. The hydraulic controllers J delay the action of the brake calipers/cylinders 19. The hydraulic/pneumatic circuits 207 and 208 brake the wheels not equipped with the motor hydro-pumps A via the hydraulic cylinders CI and C2. The brake fluid pressurized air enters the hydraulic cylinder CI through the threaded opening 133 and acts upon the piston 134 which pushes the fluid through the threaded opening 132, the connector 209 and the solenoid valve 2 to the distributor B. The brake fluid pressurized air also enters the hydraulic cylinder C2 and which when it is activated, pushes the fluid to the tapped holes 78 of the motor hydro-pumps A, and also to the fluid-type equilibrator G. Here no element is activated because the piston 148 cannot be activated by the fluid, but only by the electromagnet 144. When the fluid enters the distributor through the axial hole 1 18 B, it acts upon the piston 120, which moves axially through the tubular body 108 and through the radial hole 1 19 to activate the hydraulic switch 5. The switch 5 once activated, sends the current to the electric switch L and, from here, to the double-circuit solenoid valves 1 (Figure 33), thus opening the circuit 198 of the valve 196 and the circuit 201 of the valve 197. At the same time, the fluid pushed from the hydraulic cylinder C2 through the connectors 204, enters each motor hydro-pump A through the tapped holes 78 and reaches the circumferential passages 100. From here, through the radial passages 32, the fluid reaches under the blades 26 of the motor hydro-pumps A, driving them radially to the outside in the pressure chamber 107 to push fluid which has arrived there from the tank D through the inlet openings 57.

When using the brake pedal 20 to reduce vehicle speed, the hydraulic fluid from the distributor B acts upon the piston 120 (Fig. 22), thus forming a first circuit through the distributor B (Fig. 1), by the circumferential passage 121, which communicates with the openings 1 15, making the connection between the tapped holes 109 and 1 10. At the same time, the fluid engaged by the blades 26 is evacuated through the openings 58 of the motor hydro- pumps A and then passes through the circuits 201 of the valves 197 of the solenoid valves 1. Fluid pressure passes through the connectors 203 and 210, reaching the distributor B, passing through the holes 109 and 1 10, the valve 6, the connectors 212 and 213 and reaching the tank E, which contains pressurized gas. The pressure in the tank E, due to the gas cushion, blocks the advancement of the fluid and indirectly applies force to the blades 26 and the rotors 23, which are integral with the wheel hubs, which leads to vehicle braking.

The gas pressure in the cylinder E can stop the vehicle at the maximum speed the vehicle can reach. If the maximum admissible pressure is exceeded in the cylinder E (if the vehicle drives down a slope and the potential energy is used by braking), the one-way pressure valve 9 opens and sends the fluid surplus back to the tank D through the connector 214. In this first braking circuit for speed reduction, the blades 26 are radially extended to their maximum travel from the rotors 23 only when the circumferential passage 121 of the piston 120 fully opens the fluid passage through the openings 1 15 of the distributor B, performed through the coiled springs 46 of the blades 26 and the coiled spring 129 of the distributor B, which compress differently at the same pressure delivered by the hydraulic cylinders CI and C2.

When the brake pedal 20 is applied to fully stop the vehicle, a second circuit is opened through the distributor B, by the sliding of the piston 120, so that the circumferential passage 122 communicates with the openings 116. The fluid from the connector 210 passes through the second circuit to the valve 7 and, through the connectors 215 and 216, reaches the cylinder F, which has a higher pressure than the cylinder E, which, by the gas cushion blocks the advancement in order to reduce the braking space, thus the vehicle is stopped safely. The cylinder F can stop the vehicle at the maximum speed it can reach, but in a smaller braking space than the cylinder E. However, if the cylinder F increases the pressure over the maximum established value (only if the vehicle drives down a slope and the potential energy is used by braking), the one-way pressure valve 10 opens and sends the fluid through the connector 218 in the tank D.

Cylinders E and F are each fitted with a pressure switch 1 1 and 12, which are activated at the smallest pressure increase, sending current to the switch L.

The transition between the first circuit and the second circuit of the distributor B, (i.e., between the slowing brake activity and a stopping brake activity) is smooth and without system pressure fluctuations. The road resistance increases constantly the more the piston 120 slides through the tubular body 108, which is directly proportional to the activation of the brake pedal 20. The construction of the distributor B makes this possible, because, when the openings 115 are obstructed by the circumferential passage 121 and the openings 1 16 are obstructed by the circumferential passage 122, the sum of passage surfaces generated by obstruction is equal to the surfaces of the openings 116.

When using the brake pedal 20 to produce a maximum-effort stop in an emergency situation, the piston 120 slides towards the end of the distributor B and makes the connection in the openings 117 and the circumferential passage 123, creating a third circuit by which the oil passes through the valve 8 and the connector 217 directly into the tank D. The diameter of the openings 1 17 is smaller than the diameter of the other openings 1 15 and 1 16, thus blocking the fluid passage and offering more resistance to the blades 26, which reduces the braking distance and time.

Under the circumstances, the hydraulic controllers J start to apply pressure on the brake calipers/cylinders 19 from the transition between the second circuit and the third circuit of the distributor B. Thus, the emergency braking action is augmented by their action, increasing efficiency. The hydraulic controllers J are functionally mounted between the brake calipers/cylinders 19 and the brake pump 17 and are designed to delay the response of the conventional braking system, which is partially kept active on the vehicle wheels that are not equipped with the motor hydro pumps A. The hydraulic controllers J receive brake fluid/pressurized air through the hydraulic/pneumatic circuits 222, during the entire braking operation. The brake fluid pressurized air enters a hydraulic controller J through the tapped hole 180 and acts upon the piston 164, which is retained by coiled spring 167. When the pressure overcomes the resistance of the coiled spring 167 and allows the piston 164 to push the piston 166, brake fluid or the pressurized air is pushed through the tapped hole 182 to the brake caliper/cylinder 19, which stops the wheels. Pistons 166 act upon the brake calipers/cylinders 19 only when the second distributor circuit starts to close, by the gliding of the piston 120 through the distributor B, while the third circuit starts opening the circuits formed between the openings 1 16 and the circumferential passage 122, the openings 1 17, and the circumferential passage 123.

When the brakes are applied, the blades 26 of the motor hydro-pumps A operate in the chamber 107. The braking is smooth, and without any shocks, due to the hydraulic accumulators H, which take up the fluid surplus from under the blades 26. The fluid volume under the blades 26 is at the minimum level when only two of the blades 26 of a motor hydro pump A slide at maximum travel. When they operate in front of the surfaces 67 of the pressure chamber 107, the other two blades are retracted inside the rotors 23, in front of the blade surfaces 66. The maximum fluid volume is reached only when all four blades 26 of a motor hydro-pump A are between the surfaces 65 and 67. The difference between the maximum volume and the minimum volume of fluid under the blades 26 is taken up by the hydraulic accumulators H. Thus, the fluid is not sent back into the hydraulic cylinder C2 and does not effect the pressure experienced at the brake pedal 20.

When the brake pedal 20 is no longer depresssed, the switch 13 no longer sends current into the switch L. Thus, the solenoid valve 2 closes. The hydraulic switch 5 is not pressed by fluid and closes the circuit 198 of the valve 196 and the circuit 201 of the valve 197 in the double-circuit solenoid valves 1 (Fig. 33) by the switch L. In addition, if the brake pedal 20 is no longer depressed, the blades 26 move back into the rotors 23, as they are no longer driven by the pressure applied in the hydraulic cylinder C2 by the brake pump 17. The brake pump 17 no longer drives the hydraulic controllers J, and so the pistons 164 and 166 return to their initial positions and the circumferential passage 173 is able to communicate with the opening 172. Thus, the pressure in the brake calipers/cylinders 19 and in the connectors 222 returns to normal.

If the vehicle wheels lock under braking, the ABS intervenes. The kinetic energy recovery system under braking, according to the invention, is designed to work together with the ABS and, if the ABS intervenes and interrupts the pressure supplied by the brake pump 17, the hydraulic cylinder C2 no longer acts on the blades 26, which move radially inward. The hydraulic cylinder CI no longer operates the distributor B, so the fluid is no longer pumped by the blades 26, and the circuits through the distributor B are closed. No road resistance will be offered and braking will be discontinued.

Upon application of the acceleration pedal 21, the switch 14 is activated and sends current to the switch L, which commands the solenoid valves 1 (Fig. 34) to open the circuit 199 of the valve 196 and the circuit 200 of the valve 197, along with the electromagnet 144 of the fluid-type equilibrator G, which, once driven, operates the piston 148, which slides to discharge the fluid from inside the equilibrator G through the connector 205 and the connector 204, to reach the tapped holes 78 of the motor hydro-pumps A. From here, fluid under the blades 26 is driven towards the exterior of the rotor 23, into the pressure chamber 107. The fluid volume inside the fluid-type equilibrator G is equal to the maximum volume under the blades 26, when all eight blades 26 of the two motor hydro-pumps A are between the surfaces 65 and 67. The cylinder F is the first to discharge the pressure in order to provide extra power due to a higher pressure accumulated as compared to the pressure in cylinder E. Thus, when the acceleration pedal 21 is applied and the switch 14 is activated, switch 14 and switch 12 signal that there is accumulated pressure in the cylinder F. This opens the proportioning solenoid valve 3 through the switch L, allowing the fluid coming from the cylinder F through the connector 216 to pass towards the double circuit solenoid valves 1 through the connector 221 and the connector 203. Fluid pressure reaches through the circuit 200 of the valve 197 of the solenoid valve 1 and through the same inlet ports 57, inside the pressure chambers 107. This extends the blades 26, which will propel the vehicle, by the rotation of the rotors 23 and implicitly the wheel hubs. The fluid exits the motor hydro-pumps A through the openings 58 and passes through the circuit 199 of the valve 196 and, through the connector 202 to reach tank D. In order to avoid the uncontrolled discharge of the pressure accumulated in tank F so that the acceleration does not differ from the acceleration using the vehicle engine, proportioning solenoid valves 3 and 4 are used, controlled by the potentiometer 15 connected to the acceleration pedal 21. The potentiometer 15, through the switch L, controls the fluid flow, which passes through the proportioning solenoid valves 3 and 4.

When one of the solenoid valves 3 and 4 opens, the fluid passes from the connector 221 into the connector 21 1 towards the acceleration regulator K via the axial hole 185 and pushes the rod 187, which is retained by the coiled spring 188, so that the acceleration cable between the regulator K and the carburetor/injection pump 18 releases the tension. This allows, under acceleration, the release of the energy accumulated in the tanks E and F and afterwards, the response of the vehicle engine. When the cylinder F releases the entire energy stored as pressure, the pressure switch 12 deactivates and no longer sends current into the switch L. Thus, the proportioning solenoid valve 3 closes and, at the same time, if the cylinder E contains accumulated energy and the pressure switch 1 1 is implicitly activated, the switch L switches to the circuit between the pedal switch 14 and the pressure switch 11 and opens the proportioning solenoid valve 4. This makes the connection between the connector 219 tlirough which the fluid from the cylinder E flows and the connector 221, which brings the fluid to the motor hydro-pumps A, where the blades 26 are driven and the fluid reaches the tank D through the connector 202. When the cylinder E releases all of its pressure energy and there is no more pressure to keep the pressure switch 1 1 activated, the latter no longer sends current to the switch L and the proportioning solenoid valve 3 closes. Thus, the pressure also decreases in the connector 21 1 and the rod 187 returns to the initial position due to the force applied by the coiled spring 188. The acceleration cable between the carburetor/injection pump 18 regains tension, allowing vehicle acceleration in combination with the engine.

The acceleration regulator K can be replaced by a programmable ECU (electronic control unit) that controls the engine speed, regardless of the travel of the acceleration pedal 21. The electronic control unit (ECU) must be programmed so that, through pressure sensors located on the cylinders E and F, the ECU is able to release the restriction applied to the vehicle acceleration in reverse proportion ratio to the release of the energy in the cylinders E and F, so that the acceleration is in direct proportion to the travel of the acceleration pedal 21, and not different from the acceleration provided by the motor vehicle without the kinetic energy recovery system under braking. When the acceleration pedal 21 is no longer depressed, the switch 14 no longer sends current into the switch L. Thus, the solenoid valves 1 (Fig. 34) close the circuit 199 of the valve 196 and the circuit 200 of the valve 197. The electromagnet 144 of the fluid-type equilibrator G then releases the piston 148, which returns to the initial position due to the coiled spring 149, and the blades 26 withdraw into the rotors 23.

For vehicle forward motion, the wheels and implicitly the rotors rotate in the same direction both under braking and under acceleration.

For reverse motion, the rotors 23 rotate with the vehicle wheels in the opposite direction to the forward motion. Thus, the openings 58 become inlet ports and the openings 57 become exhaust/outlet ports. When the vehicle travels in reverse and the reverse gear is activated, the reverse motion contact 22 sends current to the switch L.

Upon braking in reverse motion, the contact 22 together with the switch 13, send current to the switch L which controls the solenoid valves 1 (Fig. 35) to open the circuit 199 of the valve 196 and the circuit 200 of the valve 197, so that admission to the motor hydro-pumps A is made through the openings 58. The rest of the braking process and recovery remaining unchanged.

Upon acceleration in reverse motion, the contact 22 together with the switch 14, send current to the switch L which controls the solenoid valves 1 (Fig. 36) to open the circuit 201 of the valve 197 and the circuit 198 of the valve 196. The rest of the acceleration process and the stored energy release remaining unchanged. If there is no energy accumulated in the cylinders E and F, the proportioning solenoid valves 3 and 4 will be closed and the vehicle will accelerate in combination with the engine. During the entire operation of this system, regardless of the driving direction or whether the vehicle brakes or accelerates, there will be small fluid losses between the rotor 23, the stator

24 and the flange 25 of the pressure chambers 107. The fluid leaked between the rotor 23 and the stator 24 will reach a circumferential passage 77 and, from here, through a radial passage 74 and a longitudinal passage 73, it will pass into the connector 206 linked to the tapped hole 71 of the stator 24. From the connector 206, the fluid reaches the connector 202, which feeds the motor hydro-pumps A with fluid from the tank D. The fluid leaked between the rotor 23 and the flange

25 reaches the circumferential passage 87, which communicates with the circumferential passage 91 through the passages 88, 89 and 90 of the flange 25. From the circumferential passage 91, the fluid passes into the stator 24 through the passage 76, which communicates with the tapped hole 71 and, implicitly, with the connector 206 through the passages 75, 74 and 73.

The detailed description of the kinetic energy recovery system under braking is described below according to a second embodiment of the invention.

The technical problem solved by this invention in the second embodiment, besides the kinetic energy recovery, involves providing four-wheel drive to a rear-wheel drive vehicle.

The kinetic energy recovery system under braking, according to the invention in the second embodiment, represented in Figure 37, is installed on a rear-wheel drive motor vehicle in order to recover the kinetic energy, but also to provide the motor vehicle with four-wheel drive.

This embodiment maintains the configuration of the first embodiment of the braking energy recovery system, provided that the motor hydro-pumps A are installed on the vehicle non-driving wheels (the front wheels in this case). Between the flange of the drive shaft from the gearbox and the universal joint, which transmits the motion from the gearbox to the rear wheels, another motor hydro-pump A' is installed, with a similar structure to motor hydro pumps A. Motor hydro-pump A' is installed between the gearbox flange and the universal joint through the holes 28' of the rotor 23', which become integral with the universal joint and the gearbox flange. The stator 24' can be mechanically fastened to a crossbeam mounted between the side members or on its frame.

Motor hydro-pump A' is connected through a double-circuit solenoid valve , with a similar structure to the solenoid valves 1, and a connector 235 to the tank D. The solenoid valve Γ is also linked through another connector 236 to the cylinder F, and is controlled by a circuit 237 from the electric switch L. Two hydraulic accumulators H' are located on the motor hydro pump A', with a structure similar to the hydraulic accumulators H.

In order to provide four-wheel drive, the following is also necessary: a fluid-type equilibrator G', similar to the fluid-type equilibrator G, connected to motor hydro-pump A' by a connector 238 and to the switch L by the circuit 239; a one-way valve 240, fitted on the connector 236; a push button 241 connected to the switch L through a circuit 242; and a solenoid valve 243 fitted on the connector 211 and linked through a circuit 244 to the switch L.

In this version, in order to recover the kinetic energy under braking, the system operates identically under the same configuration as in the first embodiment.

In the event that the non-driving wheels are also necessary for extra traction, under inappropriate road and weather conditions in order to be able to drive without any problems on snow, sand or rough terrain, the push button 241 is activated, which is mounted on board the vehicle. This activation sends current to the switch L, which sends current to the electromagnet 144' of the fluid-type equilibrator G' activating it, and also to the solenoid valve 243, which it closes, because the intervention of the acceleration regulator K under acceleration is no longer necessary, as propulsion in combination with the vehicle engine is also desired. Once activated, the electromagnet 144' operates the piston 148', which activates the blades 26' to slide into the pressure chambers 107' of the motor hydro-pump A'. The rotor 23' being integral with the vehicle universal joint, upon stepping on the acceleration pedal 21, takes over the motion from the universal joint and sends, with the help of the blades 26', the fluid from the tank D through the connector 235 to the cylinder F through the connector 236, where the energy accumulates as pressure. This pressure is released, when the acceleration pedal 21 is used, to the motor hydro- pumps A located on the non-driving wheels, rotating them. Under these conditions, motor hydro-pump A' is used to distribute the power transmitted to the driving wheels and the non- driving wheels.

If the motor vehicle is driven in reverse, the reverse motion contact 22 sends current to the electric switch L, which not only changes the circuits of the valves 196 and 197 of the solenoid valves 1, but also the circuits of the valves 196' and 197' of the solenoid valve 1 '.

When the button 241 is deactivated, the solenoid valve 243 opens, allowing fluid to pass through the connector 21 1 to the regulator K, the electromagnet 144' deactivates, and the blades 26' retract into the rotor 23' of motor hydro-pump A'.

The fluid leakages between the rotor 23', the stator 24' and the flange 25' in the pressure chambers 107' reach, through the connector 245 linked to the tapped hole 71 ' of the stator 25', into the connector 235 which feeds motor hydro-pump A' from the tank D. All the elements in the second embodiment, marked with a prime mark (for example A') are similarly constructed, having the same technical features and the same components, being different only in scale as compared with those marked without a prime mark (for example G) and described in detail with regard to the first embodiment.

In summary, a preferred embodiment of the invention relates to a system for recovering kinetic energy in a vehicle undergoing braking or accelerating activity comprising, in

combination: a plurality of motor hydro-pumps, each having a stator affixed to a frame of the vehicle and having a pair of hydraulic inlets and a pair of hydraulic outlets; a rotor within the stator and affixed to a vehicle wheel hub for rotation therewith; a plurality of vanes reciprocably associated with the rotor for selective engagement with a stator interior surface; each motor hydro-pump being in operative communication with a hydraulic distributor that is selectively activated, upon braking, to distribute hydraulic fluid circulated by the motor hydro-pumps through circuits opened, depending on braking force, to communicate with hydraulic cylinders or a pneumohydraulic tank, so that smooth braking is achieved; a pneumohydraulic tank and pneumohydraulic cylinders adapted to contain both hydraulic fluid and pressurized gas; a fluid- type equilibrator that controls the vanes which slide during acceleration; hydraulic accumulators that compensate the differential volume between the maximum and the minimum volume of hydraulic fluid which actuate the vanes, so that pressure generated by the differential volume is not sensed by the brake pedal; a hydraulic controller functionally mounted between a brake pump and brake calipers/cylinders to regulate the pressure in and to delay the action of the brake calipers/cylinders; a hydraulic regulator functionally located between an acceleration pedal and an injection pump/carburetor intended to reduce tension in a throttle cable between itself and the injection pump/carburetor, so that, during throttling, the hydraulic regulator first allows the release of kinetic energy from the pneumohydraulic cylinders and then engagement of the vehicle engine; and connecting variably configurable hydraulic and electric circuitry adapted to cause the motor hydro-pumps to act as pumps, in a first configuration, to brake the vehicle without unacceptable juddering and, alternatively to act as motors, in a second configuration, to accelerate the vehicle.

The circuitry is adapted to pressurize gas and hydraulic fluid and to use the pressurized gas and the pressurized hydraulic fluid to brake and to accelerate the vehicle.

The pneumohydraulic tank includes a cylindrical body closed at each end, an axle extending between the tank cylindrical body ends, and a piston mounted for reciprocal movement over the axle and dividing the tank into a first chamber for containing hydraulic fluid and a second chamber for containing pressurized gas. The first chamber is connected to hydraulic circuitry, whereby the system dampens pressure fluctuations emanating from the motor pumps and thus minimizes juddering. The tank cylindrical body ends are hollow hemispheres in shape, and a hub is mounted on the axle and the piston is mounted on the hub. The piston engages the inner cylindrical surface of the tank, the hub and piston which is shaped so that they do not completely enter either hemispherical end of the tank, whereby a quantity of pressurized gas and a quantity of hydraulic fluid is maintained in separate chambers within said

pneumohydraulic tank.

The hydraulic circuitry includes a first circuit configuration adapted to produce a vehicle slowing brake action, a second circuit configuration adapted to produce a vehicle stopping action within a relatively short vehicle stopping brake distance, and a third configuration adapted to stop the vehicle under emergency braking conditions. The system can include a reverse gear selector switch. The'hydraulic circuitry is configured to produce vehicle stopping action when the vehicle is moving in a reverse direction, whereby vehicle kinetic energy is recovered when the vehicle is moving in a reverse direction. In addition, four blade vanes are reciprocally mounted in said rotor, and the vanes are each angularly spaced apart from adjacent vanes by substantially 90°. Moreover, the stator includes two antipodal ports capable of functioning as inlet ports and two other antipodal ports capable of functioning as outlet ports. The circuitry can be configured to reverse the functions of the inlet ports to outlet ports and to reverse the function of outlet ports to inlet ports, whereby a kinetic energy brake recovery system is provided which operates when the vehicle is moving in either a forward direction or in a reverse direction.

The stators can be affixed to the vehicle adjacent all four wheels. The rotors are located within the stators and are affixed to vehicle wheel hubs at all four wheels, whereby vehicle kinetic energy recovery is maximized.

A selectively actuated brake pedal is connected to the variably configurable circuitry. Selective actuation of the brake pedal acts to configure the circuitry in the first configuration. An accelerator pedal is connected to the variably configurable circuitry. Selective actuation of the accelerator pedal acts to configure the circuitry in the second configuration.

The vehicle can be a rear-wheel drive vehicle including an engine, a transmission connected to the engine, a cardan drive connected to the transmission, and a differential connected to the cardan drive and to the vehicle wheels. The motor hydro-pumps are mounted on the non-drive wheels; and an additional motor hydro-pump is functionally connected between the transmission and the cardan drive, whereby additional power is provided to the non-drive wheels on demand so that the vehicle is provided with all-wheel drive. Two pressure chambers are included between the stator and the rotor, wherein the vanes actuate the hydraulic fluid from the hydraulic inlets to the hydraulic outlets. The inside surface of the stator is defined so that the blades slide with a constant stroke between a hydraulic inlet and a hydraulic outlet so as to dampen pressure fluctuations emanating from the motor hydro- pumps and thus minimize juddering. In addition, the hydraulic accumulators compensate the differential volume between the maximum and the minimum volume of hydraulic fluid that controls movement of the vanes.

In the preferred embodiment described herein, a pair of hydraulic inlets and a pair of hydraulic outlets are included. It should be understood, however, that other embodiments fall within the scope of the invention provided at least one hydraulic inlet and at least one hydraulic outlet are provided.

This invention has been described in terms of specific embodiments set forth in detail, but it should be understood that these are by way of illustration only and that the invention is not necessarily limited thereto. Modifications and variations will be apparent from this disclosure, drawings and appended claims, and maybe resorted to without departing from the spirit and scope of this invention, as those skilled in the art will readily understand. Accordingly, such variations and modifications of the disclosed system are considered to be within the purview and scope of this invention and the following claims.