DESCRIPTION

of the industrial invention bearing the title

"System for the management and control of the energy generated by thermal engines (petrol or diesel) and electric motors (reversible) used for the propulsion of ecological vehicles"

The use of hybrid systems (thermal + electrical) for the propulsion of motor vehicles is the subject of several analysis and many applications of different vehicles manufacturers.

Those hybrid systems, along with positive sides (reduction of polluting emissions and of fuel consumption), show some critical ones that we can summarize in an weight increase, in a larger management and maintenance complexity and most of all in a higher buying price for customers due to higher production costs, since these motorizations are not produced in great series thus they are within the category of special production in small lots.

The system for the management and control of the energy generated by engines

(thermal + electrical), subject of this industrial invention, thanks to the characteristics of the used devices is able to accumulate the surplus energy during some run and stop stages and to give it back during acceleration or larger request of power.

The peculiar system idea gives the opportunity to satisfy any installed propulsory power between 5 KW and 250 KW.

The group is based on a schematic configuration around an oil bathed central box

14 (see Fig. 1) of modular construction that can be assembled with the angular gears 30 that allow the mounting either of the electric motor 1 and the thermal engine 6 with variable-speed unit 15 in many different positions (lateral axis, orthogonal axis, crooked axis), in order to satisfy diversified requirements of geometrical overall dimensions inside different types of engine compartment.

The applications range from bus to taxi, to scooters family, to city cars, on which this system, beside the modularity of the whole power field (5 KW - 250 KW) and the geometrical flexibility of the overall dimensions, easily allows by simple adapter joints the possibility to mount practically all types of electric motor (brushless, at permanent magnet, etc) and thermal engine (petrol or diesel) available in the market.

This is a solution that enables the different manufacturers to easily assembly the hybrid unit that is more suitable to satisfy the specific characteristics risen from the planning requirements with a very large possibility to use commercial or standard components.

Fig. 1 explains the system components of all the propulsion apparatus. The reversible electric motor (motor-dynamo) has a rated power that varies from one sixth to one half of the power that the thermal engine 6 can supply. The thermal engine 6 drives a particular hydraulic group in which the driving shaft is keyed on the side of the compact group of hydrostatic transmission-gearbox (De Roll type) 15 that includes in a single carter feed pump, hydraulic motor, tank, conduits and valves.

On the other side of the driving shaft it is keyed a magnetic clutch 7 that operates the hydraulic pump 29 which feeds the device 28 (check-valve combined in parallel with regulator valve for flux damping) and carries out the hydraulic charge of the floating piston accumulator, managed by the special valve 27 (pressure proportional valve performing on prearranged values), pouring in the gearing group 15 feeding circuit a large delivery of oil under pressure that allows the continuous variation of the number of revolutions between the thermal engine 6 shaft and the shaft 16 of the gearing group 15.

On the shaft 16, contained in the central box 14, it is rigidly keyed the centrifugal coupling 23 that, for revolutions ratings over a certain threshold, enters into the externally toothed bell 22, putting in rotation the power shaft 10.

The oil bathed box 14 is the compact apparatus that allows the functionality of the whole system of energy management.

In case of system installation on scooters, the toothed wheel 19, keyed on the shaft

10, transmits the motion to the wheel group 18 by a toothed belt (or chain) 20, passing through the reducer 21.

In case of assembly on vehicles, on the shaft 10, it is coupled, instead of the wheel

19, the transmission-shaft 9 equipped with the flexible coupling Y that gives the motion to the differential gear and then to the driving wheels.

The axis 11 and 16-10 of the box 14 are parallel and connected among them through the silent chains 12 and 13 by means of intervention of opening and closure of electromagnetic couplings 2 and 3 operated by the management and control PLC 17 and of the centrifugal clutch 22-23, operating by variation of the revolutions of the shaft 16.

In this way it is possible to obtain the different functions of the propulsion system operating appropriately on the devices 2, 3, 23, 7 and on the thermal engine 6 and the electric motor 1.

Different types of propulsion system working: a) merely electric working of the propelling group, in which the electric motor 1, with variable rotating speed, transmits the motion to the shaft 11 of the box 14; the electromagnetic coupling 2 closes while the electromagnetic coupling 3 opens; the toothed chain 12 transmits the motion to the toothed bell of the clutch 22 that is rigidly keyed on power output shaft 10 so that the motion is transmitted to the wheels. b) merely thermal working of the propelling group: in this case the electromagnetic couplings 2 and 3 of the box 14 are both opened, the thermal engine 6 rotates the hydraulic clutch 15, allowing the variation of the number of revolutions of the shaft 16 on which it is keyed on the centrifugal clutch 23, which, at specific stated angular speed, connects the

toothed bell 22 that is keyed on the power output shaft 10, so that the motion is transmitted to the wheels. c) working of the propelling group with combined electric and thermal action during the vehicle running: in this condition the electromagnetic coupling 2 of the box 14 is close while the electromagnetic coupling 3 is open; the thermal engine 6, connected to the hydraulic clutch 15, rotates the shaft 16 of the box 14 with variable rotation speed; over a certain number of revolutions, the centrifugal expansion hub 23 transmits the couple to the clutch bell 22. The chain 12 transmits to the external plate wheel of the clutch bell 22 the torque of the electric motor 1 with suitable angular velocity fixed by the PLC 17 according to the data received from the sensor 8, so that the shaft 16 can keep constantly the same instantaneous angular velocity ώ. The output power of the shaft 10 is the sum of the electrical power plus the thermal power. The output power of the shaft 10 is available for the wheel 18 in case of scooters or for the shaft 9 in case of vehicles. d) working of the propelling group during the phase of deceleration and braking with energy recovery. In this condition the shaft 10 of the box 14 transmits the torque to the bell 22 that, through the chain 12 and the electromagnetic coupling 2 close and the 3 open, allows the rotation of the shaft 11 on which it is keyed the electric motor 1, which in this case works as a dynamo supplying electrical energy to the circuit 5, charging firstly the ultra-capacitors Uc and then the batteries group B. e) working of the propelling group during the stop phase. In this condition the thermal motor 6 raises a specific revolutions rate (not the minimum) so that the hydraulic clutch-transmission 15 can put on rotation the shaft 16 on which it is keyed the plate wheel 24 that, through the chain 13 and the electromagnetic coupling 3 close and the 2 open, allows the rotation of the shaft 11 firmly keyed on the electric motor 1, that also in this case works as generator supplying electrical energy to the circuit 5, charging firstly the

ultra-capacitors Uc and then the batteries group B. During the stop phases longer than a certain period t (from 3 to 6 seconds), the electromagnetic coupling 7 closes and starts the rotation of the hydraulic pump 29 that, through the circuit with the devices 28 and 27, charges the accumulator 26 at pressure p2. The device 25 is a heat exchanger that has to keep the temperature of the hydraulic oil at the optimum temperature between 35 ⁰ C and 55°C. The floating piston accumulator 26 is ready to return, during the following acceleration phases, the accumulated energy as pressure. f) working of the propelling group during the phase of acceleration from motionless. In this condition the coupling 7 opens and halts the pump 29, the accumulator 26 progressively discharges rendering available, at high pressure, a great volume of hydraulic oil for the clutch-transmission 15. The electromagnetic coupling 3 opens while the coupling 2 closes. The electric motor 1, fed by the circuit 5 (fast discharge of the ultra-capacitors), transmits the torque to the bell 22. In the meantime the rotating shaft 16 couples the centrifugal expansion hub 23 on the bell 22; the output power shaft 10 has a very high torque for a fast start also in presence of a slope. Then, once it is reached a certain cruising speed, the electromagnetic coupling 2 disconnects and the thermal engine 6 increases very gradually its own rotation rate, using very much less fuel and delivering very much less pollutants compared with the ones required by the acceleration ramps imposed by the single motorization. g) working of the propelling group during the phase of overload in vehicle motion. In this condition, for instance, for overcoming of great slopes or for requirement of greater power, the output power shaft 10 of the box 14 asks a torque increasing that is given by the electric motor 1, which uses the discharge, modulated by the PLC 17, supplied by the accumulators and the ultra-capacitors of the electric circuit 5. The electric motor 1 can absorb a higher power (up to 50%) than the rated one for a time between 15 and 20

seconds. The electromagnetic coupling 2 closes while the coupling 3 is open and, with an angular speed, adjusted by the PLC 17 and controlled by the sensor 8, the electric motor 1 gives to the power shaft 10 of the box 14 an increased actual power able to overcome the critical phase.

From the review of the different working conditions, it comes out the capacity of the propulsive system of this invention to economize a large quantity of energy, with consequent reduction of consumptions and polluting emissions, particularly during the urban runs. Furthermore thanks to the versatility of this propulsive system, that can accept the installation of different types of thermal engines, it turns out that it is convenient also to assemble engines fed with synthetic fuels derived from renewable sources or from hydrogen, since in this case, beside the zero polluted emissions, it is possible a better use of the engine power, keeping the engine working within the space of the torque-revolution diagram where the propulsive efficiency is higher thanks to the contribution of the accumulators and the reversible electric motor.