US2762307A

US2762307A - Rotary engines

Info

Publication number: US2762307A
Application number: US307453A
Authority: US
Inventors: George Orloff
Original assignee: British Messier Ltd
Current assignee: British Messier Ltd
Priority date: 1951-09-05
Filing date: 1952-09-02
Publication date: 1956-09-11
Anticipated expiration: 1973-09-11
Also published as: GB730560A

Description

Sept. 11, 1956 G. ORLOFF 2,762,307

ROTARY ENGINES Filed Sept. 2,-1952 2 Sheets-5heet 1 INVENTOR Sept. 11, 1956 G. ORLOFF 2,762,307

ROTARY ENGINES Filed Sept. 2, 1952 2 Sheets-Sheet 2 fig. 4.

N VEN TOR wfi M mechanism is reduced to a minimum.

United States Patent ROTARY ENGINES George Orloir, Gloucester, England, assignor to British Messier Limited, Gloucester, England, a British com- P y Application September 2, 1952, Serial No. 307,453

Claims priority, application Great Britain September 5, 1951 7 Claims. (Cl. 103-49) This invention comprises improvements in or relating to rotary engines.

It is an object of the invention to provide a small highpressure rotary engine capable of operating a hydraulic pump; the invention includes the combination of such an engine and pump in one casing. It is a further object of the invention to provide a valve gear for such an engine which is capable of operating efliciently at high speed without vibration and with minimum leakage of gas.

According to the present invention a combined prime mover and hydraulic pump unit is provided, having in combination a plurality of motor cylinders grouped around an axis and extending longitudinally relatively thereto, a group of pump cylinders similarly grouped around the axis, pistons in the motor and pump cylinders each motor piston being directly engaged with one of the pump pistons, a swash plate rotatable about said axis and operatively connected to the motor pistons to be driven thereby, a spindle for the swash plate extending along said axis, a rotary valve coaxial with and driven by the spindle, and ports controlled by said rotary valve communicating with the motor cylinders.

The motor cylinders may be located in a motor cylinder body parallel with and grouped around the axis thereof, which body is hollowed out at one end to receive and enclose a pump body containing the pump cylinders.

The rotary valve is preferably a cylindrical plug valve having peripheral ports and is located in a cylinder head of the motor cylinder body, in which head are ports connecting the valve with each of the motor cylinders in turn.

Alternatively, the motor cylinder block may have a valve face at the rear end having ports therein communieating with the cylinders, and the rotary valve bears upon the valve face and has a pressure face on the opposite side thereof from the valve-face, a main port through the valve from the pressure face to the valve face, which port lies on one side of the axis and co-operates with the ports in the valve face and a balancing port lying on the other side of the axis and also extending through the valve but opening on to the valve face at a difierent radius from the radius of the ports.

In the above described constructions the swash plate has nothing to drive but the valve and the friction of the If the hydraulic pump and the rotary engine are located in the same casing and the pressure face of the valve is supplied with pressure fluid, such as high pressure air or stream, the result will be that high pressure continuous supply of hydraulic fluid will be available from the pump in an apparatus of minimum size and weight. The valve can be balanced mechanically as well as being pressure balanced and thus the apparatus will operate at high speed without vibration and with minimum leakage.

The following is a description by way of example of certain constructions in accordance with the invention, reference being made to the accompanying drawings in which:

' of the end face of the five pistons Figure 1 is a cross section upon the line 11 of Figure 2 through a rotary engine in accordance with the invention,

- Figure 2 is a longitudinal section of the same,

Figure 3 is a longitudinal section through a preferred construction,

Figure 4 is a section through the cylinder head of the construction shown in Figure 3, and

Figure 5 is an end view of the cylinder head showing the ports therein.

Referring first to the construction shown in Figures 1 and 2, a casing 11 is provided which is broadly speaking of cylindrical form and which is hollowed out at each end, leaving however sutlicient metal in the middle to form a cylinder block 12. The cylinder block is bored out with five cylinder bores extending parallel to the axis of the casing and equidistant therefrom. The cylinder bores do not extend right through the cylinder block but stop short of one end to which each of themis connected by means of a port 13, and the port end of the cylinder block is made flat to act as a valve face 14. As viewed endwise the ports each have the shape of a flattened oval with the longest dimension arranged radially and their inner ends close to but spaced a little from the axis, sufficiently to allow between them a bore to receive a valve spindle coaxial with the casing. The outer edges of the ports are spaced by a substantial distance from the periphery of the valve face, thus leaving an outer area of the valve face which is uninterrupted by ports.

Within each cylinder is a trunk-shaped piston 15 provided with suitable packing rings and having a forward end which is hollowed out to receive a ball-shaped head of a hydraulic plunger 16. The piston around the stem of the plunger has a conical end face and the inner part bear upon a ring 17, the rim of which is Lshaped in cross section and receives a ball race 18. The inner ring of the ball race rests in an inclined seating on a member 19 keyed to the valve stem 20 and the valve stem passes through the cylinder block to a valve member 21 which works on the valve face. The angle ring, ball race and seating member form a swash plate which is driven by the pistons and serves to rotate the valve stem.

The valve on the valve stem forms an enlarged head which is large enough to overlie the ports in the valve face and which has a valve pressure face on the side remote from the valve face.

It will be recollected that the casing 11 was bored out at each end. The bore of the casing at the end which contains the valve face on the cylinder block, is of course large enough to contain the rotating valve head and it also receives a .plug 22 which fits its interior closely and is provided with a sealing ring and is held in place by a split wire ring 23 concentric with a plug and recessed into the wall of the bore of the casing but not sufiiciently to prevent it overlying at the back of the plug. The plug carries a projecting nipple 24, coaxial with itself, and adapted to be connected to a source of high pressure fluid such as high pressure superheated steam. Through the plug there extends a passage toward the valve head and within the plug just above the pressure face on the valve end there is a sliding sealing ring 25 which is urged into contact with the pressure face by a spring in the plug. Thus, if pressure is applied through the bore in the plug this pressure will have access to a limited circular area enclosed within the sealing ring and located on the head of the valve. This pressure, if unbalanced, would cause the valve to bear with a heavy force on the valve face of the cylinder block. The space Within the plug which surrounds the head of the valve is connected to a lateral exhaust port 26 on the side of the casing.

There extends through the valve from the pressure face to the face which is in contact with the valve face of the cylinder block a port 27 for the supply of pressure fluid to the cylinders. This port lies to one side of the axis of the valve and is so shaped, and timed in relation to the swash plate, as'to deliver pressure fluid to the cylinders during the time in which the pistons therein are moving away from the cylinder head toward the outer end of their stroke. The under side of the valve is hollowed out from side to side on the opposite side of the axis from the port 27 just described so that it acts as an exhaust port and gases from the cylinders on the return stroke of the plungers pass direct to the exhaust on the side of the casing. If this were all, the valve would bear with a very heavy pressure on the valve face and this pressure would be unbalanced with respect to the axis, that is to say it would be very much greater on the side of the axis where the exhaust port is located than on the side of the axis where the supply port is located. To balance the valve there is a balancing port 28 cut through it from the pressure face to the valve face and opening upon the valve face at a radius greater than the radius of the ports therein. The function of the balancing port is to balance the fluid pressure exerted at the valve face by the supply so that this pressure is balanced about the axis of the valve and also to reduce the net pressure exerted by the metal of the valve 21 upon the valve face. As the balancing port is at a greater radius from the axis than the fluid supply port or main port of the valve, the area of the balancing port can be smaller than the area of the main port. The total area of the two ports is somewhat smaller than the area of the pressure face on the back of the valve.

At the other end or" the casing the hydraulic pump is located. This end of the casing is bored out to receive a block 36 which will be called the pump plunger block. The pump plunger block contains five bores, coaxial with the bores of the pistons in the engine cylinder block. Each bore in the pump plunger block contains a hardened steel hydraulic cylinder 31 bored out and lapped to fit a plunger 16 having a ball head to fit the socket in the corresponding piston above described. Each cylinder has a flange at its rear end which overlies the rear surface of the pump cylinder block and serves to locate the cylinder therein. Outside the pump cylinder block there is a plug 32 which extends across the end of the casing and is held in place therein by a split ring 132. The space 130 between the plug 32 and the outer face of the pump cylinder block constitutes a delivery chamber for the pump. Each of the pump cylinders has an axial delivery port in its end which opens into-the pump delivery chamber and contains a ball delivery valve 131 held on its seating when not open by a fiat spring 133 in the pump delivery chamher. The same spring acts for all the pumps and consists of a steel sheet stamping having a centre portion surrounded by five radial spring arms to bear on the delivery valves of all the pumps. The inlet ports for the pumps are cut in the sides of the pump barrels and are uncovered by the plungers when these are drawn out of their cylinders by the pistons of the engine portion of the mechanism. They are connected by radial passages 33 to a central suction opening 37, which latter is connected by a nipple and appropriate pipework to thesupply. The delivery of the pump is taken to another nippic 35 which is secured in the plug which encloses the pump delivery chamber.

Referring now to Figures 3 to 5, the unit comprises a cylindrical motor cylinder body 4t} externally gilled at it for cooling purposes and containing five parallel motor cylinder bores 42 fitted with liners 43. On the end of the body are studs M which carry nuts 45 serving to hold in place a cylinder head'46 and an exhaust flange 47. In the cylinders 42 work pistons which are hollow and fitted with plugs 52 to bear on the heads 53 of pump rams 51' The rams 5?. work in liners 54 in a pump body 55. The pumpbody 55 is let into a cylindrical re- .4 cess in the end of the motor cylinder body 40 and is held in place by an end cap 56 and screwed sleeve 57.

The pump body 55 contains a ball race 58 for a swash plate spindle 59 on which is an inclined ball-bearing swash plate 60. The spindle 59 is also supported by a needle roller bearing 61 in the motor cylinder block 40. The swash plate 60 engages beneath the heads 53 of the pump rams 51 and the undersides of the heads are bevelled to suit it. The ball bearing 58 is made to take end thrust as well as side thrust, so as to support the swash plate against the pressure of the motor pistons 52 and to hold the pump rams against the pistons.

On the end of the spindle 5d are dogs 62 which drive a cylindrical valve 63 working in the cylinder head 46. The head carries a female screw thread 64- to receive a nipple on an air supply pipe (not shown) and the air pressure presses the valve 63 toward the spindle 59, the pressure being transmitted through a ball 65 and being supported by the thrust race 58 already referred to. The valve 63 has a bore 66 and lateral port 67 through which air reaches in turn each of five ports 68 cut in the head 46 and leading to the cylinders 42. On the opposite side to the port 67 the valve 63 has an exhaust port 69, which likewise co-operates with the ports 68 in the head and extends along the valve body 63 as far as an exhaust port 70 cut in the head and leading to an exhaust passage 71 in the exhaust flange 47. The passage 71 communicates with a screwed socket 72 for an exhaust pipe connection (not shown).

As will be evident the valve 63 must be timed, by engaging it with the dog 62 correctly, relatively to the swash plate 60, so that the air supply reaches the cylinders 42 through ports 67, 68 at the time when the swash plate allows the pistons 50 to move outward under the pressure and so that they can exhaust through

ports

68, 69 when moving back again.

Spring press plungers 75 bear on the ends of the barrels 54 of the pumps and act as discharge valves. The barrels at the ends where the valves 75 bear upon them are spaced a little from the end cap 56 in which the valves work and this permits the discharge hydraulic fluid to enter an annular space 76 between the end cap 56 and the pump body 55. A discharge port 77 in the end cap is provided with a screwed aperture 73 for connection to a delivery pipe. There is a screwed aperture 79 for connection to a suction pipe. This leads into a central suction chamber 80 which is connected by inclined ports 81 to inlet ports 82 in the walls of the pump barrels 54. The ports 82 are uncovered by the plungers 51 when these reach the inner ends of their stroke.

It will be seen that the general construction of this pump is similar to that of Figures 1 and 2, but the cylindrical valve 63 is preferred to the face valve 21 of Figure 2.

In either pump all the parts are extremely simple in construction.

The relative sizes of the pistons and the plungers driven thereby are such that if the casing is supplied at one end with air, steam or gas under pressure at one thousand pounds per square inch the hydraulic pump will deliver at four thousand pounds per square inch and even with a casing which is less than three inches in diameter there will be a delivery at this pressure of four cubic inches of hydraulic fluid to the system per second, that is to say, nearly 1 gallon per minute. Such a device constitutes a valuable source of pressure for use in a guided missile for the purpose of controlling the guideplane surfaces.

Iclaim:

l. A combined fluid pressure driven prime mover and hydraulic pump unit comprising in combination a block of motor cylinders closed at one end except for ports and open at the other end, said cylinders being grouped around an axis and extending longitudinally relatively thereto, a block of pump cylinders similarly grouped around the axis and closed except for ports at the opposite end from the motor cylinders, suction and delivery valve means to and from said pump cylinders, pistons in the motor and pump cylinders, each motor piston being directly engaged with one of the pump pistons, a swash-plate located between the two groups of cylinders, rotatable about said axis and operatively connected to the motor pistons to be driven thereby, a spindle for the swash-plate extending along said axis between the motor pistons, a rotary valve close to the closed ends of the motor pistons coaxial with and driven by the spindle, and ports controlled by said rotary valve directly communicating with the closed ends of the motor cylinders and a fluid pressure supply distinct from the pump supply and delivery connection to said rotary valve.

2. A unit as claimed in claim 1 wherein the motor cylinders are located in a motor cylinder body parallel with and grouped around the axis thereof, which body is hollowed out at one end to receive and enclose a pump body containing the pump cylinders.

3. A unit as claimed in claim 2 wherein the motor cylinder body and pump body each contain a bearing for the swash plate spindle.

4. A unit as claimed in claim 1 wherein the rotary valve has a pressure face on the opposite side thereof from the valve face of the cylinder block, a main supply port extends through the valve from inside the pressure face to the valve face, and is located on one side of the axis so as to cooperate with the ports in the cylinder block the rotary valve having also a balancing port lying on the other side of its axis and extending through it but opening on to the valve face of the cylinder block at a different radius from the radius of the ports therein.

5. A combined fluid-pressure driven prime mover and hydraulic pump unit comprising in combination a block of motor cylinders grouped around an axis and extending longitudinally relatively thereto, a motor cylinder head detachable from said block closing the ends of said motor cylinders and containing ports communicating therewith, an axial bore in said head into which said ports open, an axial supply port for working fluid under pressure in said head and communicating with said bore a block of pump cylinders similarly grouped about said axis, a supply and delivery connection to the pump cylinders, pistons in the motor and pump cylinders, each motor piston being directly engaged with a pump piston, a swash plate located around said axis between the motor and pump cylinders and operatively connected to the motor pistons, a swash plate spindle extending along said axis through the motor cylinder block and a rotary motor-valve on said spindle and fitting in said bore for controlling said ports in the motor cylinder head and a fluid pressure supply to said rotary valve distinct from the supply and delivery connection to said pump cylinders.

6. A unit as claimed in claim 5 including an exhaust port passing through the cylinder head which is controlled by the rotary motor-valve, an exhaust flange backing up said cylinder head, and an exhaust passage and an exhaust pipe connection in said flange communicating with said exhaust port.

7. A unit as claimed in claim 6 wherein the rotary motor-valve is a cylindrical valve having a fluid pressure supply passageway extending axially therethrough, a radial port in the wall of said cylindrical valve opening from said passageway which is adapted to be placed in communication with said motor cylinder ports, and an exhaust passage which is adapted to be placed in communication with said motor cylinder ports, said radial port and said exhaust passage communicating with different ones of said ports at a time.

References Cited in the file of this patent UNITED STATES PATENTS 2,070,880 Blum Feb. 16, 1937 2,114,076 Golz Apr. 12, 1938 2,243,978 Reader June 3, 1941 2,356,917 Chouings Aug. 29, 1944 FOREIGN PATENTS 163,857 Great Britain June 2, 1921