Field of the Invention

[0001] The present invention relates to positive displacement hydraulic machines, and more particularly to hydraulic motors

Background of the invention

[0002] Rotary engines are the alternative to conventional 4-stroke internal combustion engines. Usually a rotary engine contains a rotor-piston, which revolves in a body and feeds air or a fuel-air mixture into a combustion chamber where the fuel-air mixture burns and creates a combustion stroke by the energy of combustion products.

[0003] The Russian Federation patent No. 2477376 published on 10.03.2013 discloses a 5-stroke rotary engine, including a cylindrical rotor, provided with blades and placed into a hollow body, provided with ventilation openings and having equally-spaced cylindrical cavities on the body inner surface periphery, wherein rotary locking cylinders are mounted, the engine having the cylindrical outer surface and the circular inner surface of the rotor as well as the rotor blades' and locking cylinders' surfaces are spaced thus forming operation chambers - "expansion" segment and "exhaust" segment, and equipped with a gear drive providing transmission from the main shaft to the other rotary member shafts, wherein separate compression sections comprising blade rotors are provided inside the engine body while hollow combustion chambers are provided atop.

[0004] A drawback of the engine as above is that when two or more adjacent rotary members (in particular rotors and rotary cylinders) involved it arises a problem of the junction sealing. The gas volume abrupt expansion in the course of combustion stroke causes in its turn jump-like shock stresses arising when gas pressure being transmitted onto the rotor blades, resulting in the engine structural elements' rapid wear, and consequently in their relatively short service life significant power waste. [0005] The closest analogue of the invention as claimed, taken as its prototype, is a rotor-piston internal combustion engine described in the Russian Federation patent No. 2174613, published on 10.10.2001 , including a body with an internal cylindrical cavity and lateral covers, the body comprising a rotor-piston concentrically mounted therein and having side surfaces, radial protrusions and radial recesses on the peripheral surface of the body, wherein the rotor-piston together with the body forms segment cavities, the combustion chamber placed beyond the cylindrical inner cavity and communicating with the later though inlet and outlet passages, provided with controllable valves; outlet and inlet passages; separating vanes, mounted for radial movement in the slots of the body and the lateral cover inner surfaces between the combustion chambers' inlet and outlet passages, wherein the vanes contact the rotor-piston periphery surface and, together with the rotor-piston radial recesses, the cylindrical body inner surface and the body lateral covers, the vanes form the segment operation cavities and are connected to the control gear.

[0006] A drawback of such an engine is its structure relatively low reliability in particular caused by the presence of sliding separating vanes. The very sliding vane mounting is associated with difficulties in the connection sealing. The engine operating at high temperatures causes its structural element thermal deformation, while the loads observed cause further deformations, in general leading to a complicated stress condition of the structural elements resulting in eventual geometry changes of rotor and sliding vanes thus causing a gap between lanes and rotor.

[0007] The object of the invention is to provide a compact and economical rotor-piston internal combustion engine, which design concept will ensure its increased efficiency, performance and extended life.

Detailed Description of the Invention

[0008] The problem is solved with providing a rotor-piston internal combustion engine comprising a main body with a cylindrical cavity in which a rotor-piston is concentrically mounted, wherein the rotor-piston comprises radial protrusions and radial recesses on its peripheral surface forming in conjunction with body cylindrical inner walls, a plurality of closed segmental cavities, combustion chambers arranged in the lateral cylindrical cavities placed beyond the main cylindrical cavity and communicating with the later though inlet and outlet passages, provided with a controllable valve gear, wherein the lateral cylindrical cavities are provided with nozzles to inject fuel and spark plugs, gas distribution devices with inlet and outlet passages wherein each lateral cylindrical cavity receives a lateral rotor, each lateral rotor having three cavities with openings through its side surface, wherein the openings have a uniform linear and angular displacement relative to each other so that the projections of these three openings do not intersect with each other neither in the rotor side view nor in its axial view. The term "lateral cylindrical cavities" should be interpreted as such an arrangement of said cavities relative to the main cylinder cavity, wherein all the cavity axes are parallel to each other.

[0009] According to such a design the combustion chambers being substantially lateral rotor cavities with openings through its side surface, the fuel mixture is injected into each of the cavity openings consequently in the course of the lateral rotor angular displacement. While the fuel mixture is injected into the first cavity, the mixture previously injected is combusted in the second cavity, wherein the opening is sealed at the open side by the wall of the lateral cylindrical cavity, wherein the lateral rotor is arranged, and the fuel mixture exhaust contained in the third cavity is ejected from the third cavity opening. Thus, one of the cavities contains the fuel mixture previously injected, another one contains burning fuel mixture and yet another - the fuel mixture exhaust. Due to such a design and the combustion chambers' opposite phase operation the fuel mixture is combusted within a small volume of a lateral rotor cavity, that ensures its complete combustion thus reducing wastes, and consequently increasing the motor efficiency and performance. Exactly three cavities provided in the lateral rotor are specified as far as in the case of their minor number the fuel mixture will not be able to burn completely, and thus the process will be completed in the segment cavity, furthermore, due to such a lateral rotor configuration it is ensured the absence of the motor operation dead centres. The cavity number as stated allows for combustion at 240° lateral rotor angular displacement, resulting in complete fuel combustion. Besides, it is thus cavity number that allows for providing the most uniform and consistent concentric arrangement, as well as for synchronising operation of the motor elements, such as lateral rotor, controllable valve gear etc. free from additional synchronising elements, complicating the motor design and reducing its durability.

[00010] A larger number of combustion chambers (two times if compared with conventional designs archived by providing three cavities in the lateral rotor) allows for increasing the swept volume, thus increasing the engine capacity.

[00011] The most suitable shape of the combustion chambers, being the lateral rotor cavities with openings through its side surface, is chosen empirically based on the need to ensure the conditions for the most efficient combustion of the fuel mixture injected to the combustion chambers, as well as on the task to provide efficient operation of the rotor-piston internal combustion engine as claimed. Thus, for example, it is possible to implement the invention as claimed, wherein the cavity forming the combustion chamber has a generally rectangular shape. Also it is possible an embodiment wherein the cavity forming the combustion chamber has a generally elliptical shape the ellipse oriented vertically in space its major axis being parallel to the lateral rotor axis.

[00012] Moreover, the design of the rotor-piston internal combustion engine as described has small dimensions in comparison with a conventional engine, for the engine as claimed does not include structural elements needed to convert the translational motion of the piston into rotary motion of the crankshaft, since a rotor being the principal member of the engine as claimed performs the rotational movement as it is. Also the rotor- piston internal combustion engine design is characterised by the absence of components operating in abrupt impact loads, by reduced or no alternating loads, that in turn extends the engine operational life. [00013] It is preferable such a rotor-piston engine embodiment wherein the engine comprises a rotor-piston with 6 radial protrusions and 6 radial recesses, the engine including 12 combustion chambers. It is possible such an embodiment wherein the radial protrusion vertices are connected by straight lines or wherein the radial recesses are of a curved configuration. Such an engine embodiment ensures its optimal operating characteristics.

[00014] Each rotor-piston engine gas distribution device can be provided as a cylindrical cavity that opens into the main cylindrical cavity by means of the inlet/outlet passages coming therethrough. Further, each gas distribution device comprises a screw rotor, rotatably mounted without stoppages and divided into three parts, two of which are designed to inject fresh air into the main cylindrical cavity main, and the third one - to eject exhaust gases.

[00015] It is also possible such an embodiment of the invention as claimed wherein each gas distribution device is formed as a pair of cylindrical cavities opening into the main cylindrical cavity by means of the inlet/outlet passages coming therethrough, wherein one cylindrical cavity is provided with a means for injecting fresh air and another one - with a means for ejecting exhaust gas.

[00016] Such devices may be, for example, screw rotors, turbines, or other means used in the art. The exhaust gas moving through the gas distribution device outlet passages may be fully or partially retained by an angular displacement of an outlet pendulum arranged in a cavity specially provided in the engine body and configured to match the outlet pendulum. The outlet pendulum body includes exhaust gas passages provided to reduce the pressure of the hot exhaust gas that fills up corresponding operation cavities before its ejection, and to facilitate gas ejection. The gas moving through the gas distribution device inlet passages (gas distribution device sealing) may be fully or partially retained directly by the rotor-piston side surface. Such an embodiment of the technical solution as claimed allows to provide high quality and timely removal of the fuel mixture combustion products (exhaust gas) out of the combustion chambers, providing, in turn, good conditions for fuel mixture combustion in the combustion chamber, and hence - increasing the energy efficiency of the engine as a whole. Furthermore the embodiment as described allows to provide forced air supply (air being compressed), thereby increasing the calorific value of corresponding operation chamber that, in turn, increases the capacity of the engine as claimed.

[00017] An appropriate embodiment of the invention as claimed is that wherein the controllable valve gear contains a rotary pendulum, a rotary pendulum shaft and a rotary pendulum desmodromic. The rotary pendulum body is provided with three passages for passing fuel mixture combustion products, arranged so that each passage position corresponds to the position of the combustion chambers, formed as cavities with openings in the lateral rotor side surface, i.e. said passages have a uniform linear displacement relative to each other and do not overlap in the rotor side view. Besides the rotary pendulum body is provided with three passages for passing compressed air into combustion chambers, the passages arranged so that, each passage position corresponds to the position of the combustion chambers, formed as cavities with openings in the lateral rotor side surface, i.e. said passages have a uniform linear displacement relative to each other and do not overlap in the rotor side view. Whereby the passages for passing fuel mixture combustion products and passages for passing compressed air are arranged relative to each other so that it is provided their uniform angular displacement relative to each other and their overlap in the rotor side view. Such an embodiment of the invention as claimed allows for the forced movement of the rotary pendulum preventing wear rotor, which may arise as a result of the pendulum impact onto the rotor surface. The presence of passages for passing fuel mixture combustion products allows to reduce the pressure of the hot exhaust gas that fills up corresponding operation cavities and to facilitate gas ejection through the gas distribution device. The presence of passages for passing compressed air to the combustion chambers allows to accord the supply rate of a fresh air portion with the combustion chamber operation to provide the most efficient mixing in each of the operation chambers.

[00018] The invention is explained in further details with reference to the figures illustrating an exemplary embodiment of an engine containing six segment operation cavities and twelve combustion chambers, arranged in four lateral cylindrical cavities, as well as a lateral rotor containing three cavities arranged therein:

[00019] Fig. 1 - an embodiment of the engine in cross section;

[00020] Fig. 2 - another embodiment of the engine in cross section;

[00021] Fig. 3 - lateral rotor general view;

[00022] Fig. 4 - lateral rotor general view;

[00023] Fig. 5 - ^■ a schematic drawing illustrating the positions of the lateral rotor three cavities depending on the angular displacement angle of the lateral rotor relative to its initial position.

[00024] Fig. 6 - general view of a controllable valve gear rotary pendulum.

[00025] The engine consists of a body 1 , being a stator, including a main cylindrical cavity and lateral covers (not shown) (Fig. 1, Fig. 2). The body 1 cylindrical cavity includes a rotor-piston 2, concentrically mounted therein and having side surfaces, radial protrusions 3 and radial recesses 4. The rotor-piston 2 side surfaces fit the stator body 1 lateral covers, and the rotor-piston 2 radial protrusions 3 fit the cylindrical inner walls of the stator body 1 main cylindrical cavity. The radial protrusions 3 and radial recesses 4 together with the body 1 inner walls form closed segmental cavities 5. Four lateral cylindrical cavities 6 are concentrically spaced in the body 1 beyond its main cylindrical cavity and communicating with the later though inlet and outlet passages 7 and 8 for supplying fuel mixture air and ejecting the exhaust gas correspondingly. The lateral cylindrical cavities 6 are provided with lateral rotors 9 wherein cavities 10 with openings form combustion chambers. Fig. 1 shows an embodiment of the solution as claimed, wherein the body 1 is provided with inlet 11 and outlet 12 passages arranged beyond its main cylindrical cavity, spaced pairwise and concentrically in the body 1 between the lateral cylindrical cavities 6. Both passages communicate with the chamber 13, connected to a turbocharger (not shown) and provided with a screw rotor 14.

[00026] It is possible such an embodiment of the solution as claimed, wherein the body 1 is provided with gas distribution devices arranged beyond its main cylindrical cavity and formed as a pair of cylindrical cavities, one comprising a means 15 for injecting fresh air and another - a means 16 for ejecting exhaust gas, wherein said cavities open into the main cylindrical cavity by means of the inlet 7 and outlet 18 passages, correspondingly, coming therethrough.

[00027] The body 1 slots between the inlet 7 and outlet 8 passages receive valve gears 19 rotatably mounted, each one comprising a rotary pendulum 20, a rotary pendulum shaft 21 (Fig. 6) and a rotary pendulum desmodromic (not shown). The rotary pendulum is provided with three passages 22 for passing fuel mixture combustion products and three passages 23 for passing compressed air into combustion chambers. Besides, the outlet passages 12 and 18 of the gas distribution devices are provided with outlet pendulums 24, the pendulum bodies comprising exhaust passages (not shown).

[00028] Together with the rotor-piston 2 radial recesses 4, the body 1 cylindrical inner walls (inner surface) and the lateral covers said valve gears 19 divide segment cavities 5 into two parts.

[00029] The valve gears 19 are controlled by means of a desmodromic, performing their angular displacement according to the rotor- piston 2 angular displacement angle to enable their sliding over the rotor- piston 2 radial protrusions 3 and radial recesses 4 and to make them divide two adjacent parts of segment cavities 5, formed by closed segments, with minimum leakage. It is clear that all the members contributing to the adjacent segment cavities 5 division, are provided with seals neither considered nor described herewith.

[00030] In addition, the engine is provided with conventional systems to ensure its operation: fuel feed system, either carburetor or injection one, lubrication system, power supply system, exhausting system and other standard systems and devices for internal combustion engines that are not described herein.

[00031] Finally, the described structure may be a unit of an engine consisting of a number of such units having a common shaft and common supporting systems, in particular, the engine may consist of rotar-piston units, drive units, and junction blocks, i.e. a 2-rotar engine, a 4-rotar engine, a 6-rotar engine and an 8-rotar engine are possible. The engine junction block can be of a polyhedral shape the other corresponding engine units being attached to each of its faces.

[00032] Fig. 3 and Fig. 4 show a lateral rotor 9 having three cavities 10

- 25 (not shown), 26 and 27 comprising openings provided through its side surface. The openings have a uniform linear and angular displacement relative to each other so that the projections of these three openings do not intersect with each other neither in the rotor side view nor in its axial view. The openings are displaced relative to each other by the vertical axis at a height of an opening.

[00033] Fig. 5 schematically shows the positions of the lateral rotor 9 - 25, 26 and 25 three lateral cavities 10 depending on the angular displacement angle of the lateral rotor 9 relative to its initial position.

[00034] In position I of the lateral rotor 9 the fuel mixture is injected into the cavity 25 while in the cavity 26 it is compressed and in the cavity 27

- it is combusted at constant volume. After a 120-degree rotor angular displacement the compression is observed in the cavity 25, the combustion at constant volume is observed in the cavity 26 and the combustion stroke is observed in the cavity 27. After another 120-degree rotor angular displacement the combustion at constant volume is observed in the cavity 25 the combustion stroke is observed in the cavity 26 and the compression is observed in the cavity 27.

[00035] In a simplified representation the rotor-piston internal combustion engine as claimed operates as follows. The rotor-piston 2 rotates in a cylindrical cavity of the body 1 wherein the valve gears 19 slide over the rotor-piston protrusions 3 and recesses 4 resulting in cyclic change of all the segment cavities' volumes from the minimal value up to the maximal one.

[00036] The air is injected through the inlet passage 7 out of the segment cavity 5 located upstream the lateral cylindrical cavity 6 into the lateral rotor 9 cavity located in the lateral cylindrical cavity 6 of the body 1. Meanwhile, said lateral rotor 9 cavity is not in communication with the outlet passage 8, i.e. in this cavity the compression stroke is observed. The volume of this segment cavity 5 being close to minimum, i.e. after the compression stroke completing, the lateral rotor 9 performs a 120° angular displacement, whereby the fuel mixture is combusted at constant volume in said lateral rotor 9 cavity closed by the lateral cylindrical cavity 6 wall. After another 120° lateral rotor 9 angular displacement the combustion stroke is observed and said cavity containing combustion products communicates with the outlet passage 8, the exhaust gas is ejected through. Simultaneously the same is observed in the other two lateral rotor 9 cavities at a stroke displacement. Pressurised combustion products are fed through the outlet passage 8 into the segment cavity 5 downstream the valve gear 19, causing a torque to be applied to the rotor-piston 2 due to the combustion product pressure tangential component. In other words, in said segment cavity 5 a combustion stroke is observed.

[00037] Thus, the invention as claimed is a compact and economical rotor-piston internal combustion engine, which design concept will ensure its increased efficiency, performance and extended life.