Field of the invention

The invention relates to a rotary piston machine especially rotary combustion engine comprising at least one rotatably mounted cylinder block containing at least one cylinder perpendicular to the axis of rotation of the cylinder block and housing a piston adapted to reciprocate and connected with a piston rod coupled with a planet gear meshing with a stationary gear rim seated in axial alignment with the cylinder block

Background of the invention

In a well-known embodiment of the rotary piston machine described for instance in the GB 1,231,701 the actuating force acting on the piston of the rotary combustion engine is transmitted on planet gears by means of the classical crank mechanism

The drawback of this solution consists in imperfectly balanced inertia forces and in the friction due to the action exerted by the piston on the cylinder These drawbacks are additionally increased by the rotation of the crank mechanism in the cylinder block

Another well-known solution of the rotary piston machine described in US 3,924,516 uses an eccentric pin of planet gears which are in engagement with a stationary gear rim The piston is maintained in the position coaxial with the cylinder merely by the guiding of the piston in the cylinder which involves increased friction between the cylinder and the piston and, consequently, increased wear in particular of the cylinder Another drawback consists in the limited reliability of the mesh of the planet gears with the stationary gear rim.

Summary of the invention

The above described drawbacks of the state of art have been removed by the rotary

piston machine according to the invention whose pnnciple consists in that the planet gear is rotatably mounted on a swing-revolving arm and in its turn mounted in concentric alignment with the cylinder block

In this arrangement, the planet gear is in perfect mesh/engagement with the stationary gear nm positively eliminating the risk of their mutual spontaneous disengagement

Preferably, the planet gear is rotatably mounted on the piston rod that at least in the area of its connection with the planet gear is mounted in a radial guiding parallel with the axis of the related cylinder thus ensuring the axial alignment of the piston guiding in the cylinder without lateral deflection of the piston motion with the ensuing substantial reduction in wear of the cyhnder m the operation of the rotary combustion engine

The swing-revolving arms can be seated concentric alignment with the cylinder block merely by means of the planet gears and of the gear nm provided that they contain at least two cylinders

In the variant with a greater, even number of the cylinders of the rotary piston machine, the piston rods related to the pistons of each cylinder are coupled with the planet gears preferably on alternating sides of the piston rods with respect to the plane of the axes of the cylinders

This arrangement offers a constructional solution to the rotary piston machine equip¬ ped with a greater number of cylinders

Preferably, the planet gears situated on one and the same side of the piston rod with respect to the plane of the axes of the cylinders are mounted on swing-revolving arms and coupled into one unit situated with respect to the plane of the axes of the cylinders outside said planet gears thus simplifying the construction of the rotary piston machine and at the same time perfectly ensuring the constant character of the mesh/engagement between the planet gears and the gear nm related to them

A simple transmission of the torque can be achieved if the rotary piston machine contains two cylinder blocks mounted to each other in opposit revolving direction on a

common stationary shaft, the cylinder blocks being equipped with a bevel gear meshing with a bevel gear of the output shaft.

The rotary piston machine especially rotary combustion engine according to the invention can be further improved by inserting shovel-shaped lugs between the cylinders of the rotary piston machine intended to drive cooling air between the cylinders of the rotary piston machine and thus to improve its cooling effect.

Description of the drawings

An example of embodiment of the rotary piston machine according to the invention is schematically shown in the enclosed drawings in which Fig. 1 shows a horizontal sectional view of the engine fitted with two rotary cylinder blocks, the sectional view being carried out in only one of the rotors. Fig. 2 shows a vertical sectional view of one of the rotors, Fig. 3 shows a detail of the position of the oil channels in the stationary gear wheel, Figs. 4a to 4d show the mutual positions of the mechanism parts in each of the stages of the engine operation, and more exactly, Fig. 4a, during the waste gas outlet, 4b, during the suction, 4c, during the compression, and 4d, during the expansion. Figs. 5a and 5b schematically show the principle of cooling air stream regulation by means of an open or closed bimetallic couple

Specific description

The group of the rotary piston machines includes rotary piston pumps, pneumatic rotary piston engine, hydraulic rotary piston engines, rotary piston compressors, rotary pis¬ ton vacuum pumps, and rotary combustion engines.

In the embodiment according to the invention, all the above rotary piston machines comprise the same piston mechanism. Therefore in the examples of embodiment to folow, the invention shall be described in application on the rotary combustion engine only as a

representative of the whole group of the rotary piston machines.

In the shown example of embodiment, the rotary combustion engine comprises two cylinder blocks I each of which comprising radially arranged cylinders 2 housing pistons 3 adapted to reciprocate therein and individually coupled each with its related piston rod 4 The piston rod 4 of each piston 3 is coupled by means of a pin 5 with its related planet gear 6 each of which is rotatably mounted on one of swing-revolving arms 7 by means of a support pin 1. The pin 5 is seated in the planet gears 6, 6. excentrically with respect to the axis of rotati¬ on of the planet gear 6

In the shown example of embodiment, one cylinder block 1 contains eight radially arranged cylinders 2 divided into two groups of four cylinders 2 each, the cylinders 2 of the two groups being arranged alternatively. The four planet gears 6 of the one group of the cylinders 2 are situated on one side of the plane a of the axes 102 of the cylinders 2, and the four planet gears _ of the other group of the cylinders 2 are situated on the opposite side of the plane a of the axes 102 of the cylinders 2. The swing-revolving arms 7 of each four cylinders 2 are fixed to each other so as to form a four-arm cross and are at the same time positioned, with respect to the plane_a of the axes 102 of the cylinders 2, outside the planet gears 6, 6^ of the related group of cylinders 2.

In the area of the pin 5, the piston rods 4 are slidingiy guided, and adapted to reciprocate, in radial guidings 8. The planet gears 6, _[ consist of gear wheels meshing with the inner gearing of a gear rim 9, one gear rim 9 being related to each of the two groups of the planet gears 6, 6\ The gear rims 9 with inner gearing are mounted in concentric alignment with the cylinder block on a stationary shaft 10 in a fixed manner while the cylinder block 1 is mounted on the stationary shaft 10 rotatably by means of bearings H made in the shown example of embodiment as rolling-contact bearings. Also mounted on the stationary shaft 10, by means of bearings 12, are the swing-revolving arms 7 of the two groups consisting of four cylinders 2 each.

The arms 13 of the gear rims 9 are situated on the outer side of the swing-revolving arms 7 of the related group of cylinders 2 with respect to the plane a of the axes 102 of the cylinders 2 In the arms 13 of the gear rims 9 there are provided radially oriented channels 14 reaching from the gear rims 9 to the arsa of the bearings ϋ and 12.

The upper parts of the cylinders 2 are surrounded by a cylinder head 15 on whose in¬ ner surface 16 bear cylindrical packing rings 17 seated in ring-shaped grooves provided in the upper ring-shaped surface of each cylinder 2. Passages 19 are established between the cylin¬ ders 2 of the cylinder block 1 Outer jackets of the cylinders 2 are fitted with cooling ribs 20 Shovel-shaped lugs 2_1 reaching into the area of the passages 19 serve to drive cooling air insi¬ de the cylinder block Such shovel-shaped lugs 21 can be made also as a part of the cylinder block \.

The rotary combustion engine is encased in a closed sleeve 22 passing on the sides into covers 23 of the cylinder heads 15. On one of the covers 23 there is provided an inlet member 24 of cooling air designed to suck in cooling air into the inner space of the closed sleeve 22 due to the underpressure generated by the rotation of the shovel-shaped lugs 2J_, while an out¬ let member 25 of cooling air. situated on the other cover 23 of the cylinder heads 15, lets the cooling air get out Between the inner space of the cover 23 of the cylinder head 15 and the inner space of the closed sleeve 22 is introduced a bimetallic couple 37 serving to speed up the reaching of the operating temperature of the rotary combustion engine after its start. With the engine in cold state, the bimetallic couple 37 is open thus making the cooling air circulate between the inner space of the cover 23 of the cylinder head 15 and the inner space of the clo¬ sed sleeve 22 so that the rotary combustion engine soon reaches its operating temperature. Upon this, the bimetallic couple 37 closes so that the cooling of the engine is provided for only by fresh cooling air entering through the inlet member 24 and then blown out through the out¬ let member 25

The combustion mixture required for the operation of the rotary combustion engine is sucked in through a suction duct 26 into each of the cylinders 2, and the waste gases are

removed through an outlet duct 27. To obtain the combustion mixture, an injection jet 28 reaches into the suction duct 26 Spark plugs 29 serve to ignite the compressed mixture

As is shown in Fig. 1, the stationary shaft 1_0 carries the two cylinder blocks 1 operating in opposit revolving direction. Provided on the adjoining sides of the cylinder blocks 1 there are bevel gearings 30 meshing with a bevel gear 31 situated and concentric on an output shaft 32 and transmitting the power from the rotary combustion engine to a well-known not illustrated clutch or to a gear-box. The output shaft 32 is seated in a bearing 33 between the two rotary cylinder blocks ! The inner space of the cylinder blocks 1 with the planet gear is sealed by means of lateral covers 34, 35 and contains also the required lubricating oil fed by centrifugal force to the bottoms of the cylinders 2 and there entering the oil channels 14 provided in the supporting arms 13 and thus arriving again at the centre so as to lubricate the bearings JJ _. and 2 holding the cylinder block 1 and the swing-revolving arms 7 respectively.

The sleeve 22 of the rotary combustion engine is fitted with fixing members 36 for mounting the rotary combustion engine on an undercarriage.

Figs. 4a to 4d show the course of motion of the related parts in the area of one of the cylinders 2, and in particular the relative motion of the cylinder 2 with respect to the swing-revolving arm 7. Also shown are the vectors of the forces acting upon the mechanism

The ratio between the number of teeth of the planet gear 6 and the gear rim 9 is 1 to 4, thus producing two four-stroke working cycles of the engine per one revolution of the cylinder block 1. In a corresponding way, the circular ring of the related cylinder head 15 is fit¬ ted with outlet and inlet channels and the inner surface 16 ensuring the closed state of the cy¬ linder 2 during the compression and expansion stages.

The principle of the transmission of the axial operating force, acting during the expansion stage on the piston 3, on the tangential force acting on the cylinder block 1 from which the power is then taken consists in that the piston rod 4 imparts by means of the piston rod pin 5 rotary motion to the planet gear 6 meshing/engaging with the stationary gear rim 9

Due to this engagement, the planet gear 6 moves along its planet path. Since the planet gear 6 is via the pin 5 of the planet gear 6 coupled with the piston rod 4, the planet gear 6 imparts motion also to the piston rod 4 and, due to the seating of the latter in the radial guidings 8, it imparts rotary motion to the cylinder block 1.

Analogically, during the stage of the waste gas removal, suction, and compression, the force is transmitted in the reverse direction, i.e., from the cylinder block }, acting as a flywheel, to the piston 3.

During the operation of the rotary combustion engine, the cylinder block 1 rotates uniformly due to its big inertia mass. The four-arm cross made of the swing-revolving arms 7 alternatively reduces and increases its speed with respect to the stationary rim 9, and swings with respect to the cylinder block 1