US2694982A - Hydraulic machine - Google Patents

Description

N 3, 1954 o. F. QUARTULLO ET AL 2,694982 HYDRAULIC MACHINE Filed Sept. 13, 1951 5 Sheets-Sheet l INVENTORS Ga /4505 E Qumruua y HEN/F 54,405

ATTU/FA/EY Nov. 23,, 1954 Filed Sept. 13, 1951 I f t 0 m IN V EN TORS ORPHEUS F. Qua? TL/LAO M DE y HENRY I AMY Nov. 23, 1954 o. F. QUARTULLO ET AL HYDRAULIC MACHINE Filed Sept. 15, 1951 3 Sheets-Sheet 3 INVENTORS 14 TTURNB United States Patent Ofifice HYDRAULIC MACHINE Orpheus F. Quartullo, South Euclid, and Henry Baade, Cleveland, Ohio, assignors, by mesne assignments, to Oliver Iron and Steel Corporation, Pittsburgh, Pa., a corporation of Pennsylvania Application September 13, 1951, Serial No. 246,454 1 Claim. (Cl. 103-125) This invention relates to an improved hydraulic machine which can be used either as a hydraulic pump or a hydraulic motor.

A number of hydraulic machines adapted to perform the function of this invention have been heretofore proposed employing some form of rotor having a vane or blade slidably engaging the inner surface of a cylindrical bore. While such pumps, or motors, as the case may be, are in theory quite simple, when designed to handle large amounts of power or fluid under high pressure, they have proved expensive and diflicult to manufacture and keep in operation. This has been due, among other causes, to the close tolerances required between moving and stationary parts to maintain effective sealing against seepage of the fluid past the vane or past the end faces of the rotors adjacent the ends of the cylindrical bores.

Furthermore, it has been suggested in known devices of the type described to make the housing of the machine from a plurality of plates which are secured together by a number of tie-bolts but structures of this type offer extreme complications from a manufacturing and maintenance standpoint, particularly in view of the close tolerances required.

It is the general object of this invention to avoid and overcome the foregoing and other diflieulties of and objections to prior art practices by the provision of an improved hydraulic machine of the double rotor and interposed valve type which is less expensive to manufacture and maintain and which is capable of operating at higher pressures than has heretofore been practical.

It is another object of the invention to provide a rotary hydraulic machine in which the rotors and valve assemblies operate within a single casting comprising a cylinder block housing, obviating the necessity of having carefully machined cylinder blocks with laminated side plates for closing off the ends of the cylinders and sealing the end faces of the rotors.

Another object of the invention is to provide a hydraulic machine of the type described wherein any fluid which escapes past the rotor-to-cylinder bore seal is returned back into the fluid system whereby the weight of the machine can be greatly reduced in any given horsepower size.

Another object of the invention is the provision of a rotary hydraulic machine characterized by high efliciency, low cost in manufacture and upkeep, light weight, and long life.

The aforesaid objects of the invention, and other objects which will become apparent as the description proceeds, are achieved by providing a rotary hydraulic machine comprising a main housing block having two axially-parallel, spaced bores therethrough, a rotor mounted in each bore, a pair of flanges spaced intermediate the ends of the rotor slidably engaging the wall of the bore whereby an annular fluid-receiving chamber is formed. A vane or blade is provided in the annular space which is secured between the flanges of the rotor and slidably engages the wall of the bore. A counterbored hole in the housing is provided intermediate the rotor-receiving bores in which one end of a rotary valve is journaled. The valve itself is cylindrical and is in rolling engagement with the rotors between the flanges, thereby forming a block controlling the flow of fluid in the annular space. A gear. connected to the end of the valve meshes with gears on the rotors for effecting positive rotation between the valve and motors. A clearance notch is provided on the valve to receive the vane on each v opposite end of the housing,

2,694,982 Patented Nov. 23, 1954 rotor in turn and the relative angular position between the rotors and valve is such that the vanes in the rotors are received alternately in the valve notch as the several members rotate relative to each other. A fluid passage in the housing interconnects the two annular chambers adjacent one side of the rotary valve, and outlet and inlet passages connect with the annular chambers adjacent the opposite sides of the rotary valve. An end bell in sealed relation to the housing supports a drive shaft which is geared within the housing to the rotors. A fluid pressure seal is provided on the shaft to prevent leakage of any fluid from within the housing which collects in the space between the end bell and the main housing as a result of A cover plate is provided to seal the and spring-loaded relief valves in each of the inlet-outlet passages connect with the spaces at either end of the housing whereby any fluid accumulating within these spaces is returned back to the fluid system when the pressure within these spaces exceeds that in the low-pressure side of the hydraulic machine.

For a better understanding of the invention, reference should be had to the accompanying drawings, wherein:

Fig. l is a longitudinal cross-sectional view of one embodiment of the invention;

Fig. 2 is a transverse cross-sectional view taken substantially on the lines 11-11 of Fig. 1 and showing the fluid path through the hydraulic machine;

Fig. 3 is a fragmentary cross-sectional view taken substantially on the lines III-III in Fig. 2 showing the relief valves;

Fig. 4 is an end view of the hydraulic machine with the cover plate and relief valves removed;

Fig. 5 is a longitudinal cross-sectional view of another form of the invention designed to transmit tractive power to a vehicle wheel; and

Fig. 6 is a transverse cross-sectional view taken substantially on the lines VIVI of Fig. 5.

With specific reference to the form of the invention illustrated in Figures 1, 2 and 3, the numeral 10 indicates generally the main housing in which spaced bores 12 and 14 are provided. Rotors, usually made of high-grade steel, indicated generally at 16 and 18, are rotatably received in the bores 12 and 14 respectively. Each rotor has a hole 22 through its center forming a passage for fluid. A spur gear 24 is associated with each rotor, for example, by cutting the gear integrally with the rotor, and it is through the gear that torque is delivered to or from the rotor. Two flanges 26 and 28, intermediate the ends of the rotor, are integrally formed thereon and closely but slidably engage the inner walls of the bores 12 and 14 around the periphery thereof, forming an annular chamber 30 through which the hydraulic fluid passes. A clearance of .0005, for example, may be provided between the bores and the flanges. Flanges 26 and 28 thus form the confining walls of the annular chamber 30, and provide a reasonably effective practical seal against the pressure of the fluid within the annular chamber 30, particularly when the flanges are relatively wide in an axial direction, as shown.

The ends of the rotors or the flanges on the rotors form bearings 32 and 34 which slidably engage the inner walls of the bores 16 and 18. It will be understoodthat the rotors can be chrome-plated or case hardened if desired, and that the housing 10 is of a good grade cast iron alloy so that excellent bearing relationship is provided. Or separate bearings of the bronze or sintered metal type, or of ball or roller bearing type, may be provided for the rotors in the bores.

Each rotor is provided with a blade or vane against which the hydraulic fluid can react as the fluid passes through the annular chamber 30. The blade or vane can be made integral with the rotor, but in the form of the invention shown, a vane insert 36 is employed having an edge 31 slidably engaging the bore Wall, usually with a sliding clearance of about .0005" to hold leakage to a minimum. The vane 36 is received in a slot 38 cut into the rotor 20 in such a manner that the vane 36 bridges the annular chamber 30.

perating in conjunction with the rotors effect the flow of fluid through the annular 16 and 18 to chambers 30 into operative engagement with the vanes 36 is a rotary valve assembly of high-grade steel, indicated generally at 40, consisting of a main valve body 42 formed with trunnions 44. The trunnions 44 are rotatably supported by means of sleeve bearings 45 which are pressed 11110 the housing on either side of the main valve body 42 in holes 46 and 48. Hole 46 is formed in the main housing intermediate the two bores 12 and 14. Hole 48, in which the other bearing 45 is pressed, is formed in a cap 50 which is bolted to the main housing 16 after the rotors 16 and 18 and valve assembly 40 are assembled into position. The cap 50 is secured in place by four cap screws 52 As above described in conjunction with the bearings for the rotors, the sleeve bearings may be omitted with the trunnions of the valve body being journaled directly in the housing 10 and cap 50, or ball or roller bearings may be used, particularly in higher horsepower machines.

The valve body 42 is substantially in the shape of a cylinder having a circumference preferably identical with that of the inner circumference of the annular chamber 30 on each rotor. The width of the valve body 42 is such that it has a running fit between the flanges 26 and 28. As seen in Fig. 2, the rotors 16 and 18 have rolling contact with the outer periphery of the valve body 42. In order that the vane of each rotor can turn past the valve body 42, a notch 54 is provided in the periphery of the valve body. This notch alternately receives the vane 36 of each rotor, without the vanes contacting the notch.

The hole 46 in the main housing 10 is counterbored at 56 (see Fig. 2) to provide a cylindrical space in which the valve body 42 slidably rotates. It will be appreciated that the size of this counterbore is such as to intersect the bores 12 and 14- in the same way that the flanges of the rotors overlap or intersect the valve body 42. This is best shown in Fig. 2.

Closing one end of the main housing 10 is a cover plate 60 and closing the other end is a drive shaft supporting bell 62. Cap screws 58 extending through the cover plate 60, holes in the housing 10, and into tapped holes in the bell 62 secure the entire assembly together. Integrally formed with the cover plate 60 and supporting bell 62 are the supporting lugs 64 on which the hydraulic machine is mounted. The bell 62 rotatably supports, by means of bearings 66 and 68, the drive shaft 70. The shaft 70 is in line axially with the valve trunnion 44 and is engaged therewith by some suitable disconnect means, such as a tongue and groove coupling, as shown at 72. A spur gear 74 is provided on the inner end of shaft 70, and the gear may be cut directly on the end of the shaft if desired. The gear 74 engages the spur gears 24 on the rotors. The pitch diameter of the three spur gears is the same and equal to the diameter of the valve body 42 and the inner diameter of the annular chambers 30. The relative angular positions of the rotors and valve are such that the vanes 36 alternately are received in the notch 54 but do not touch the walls of the notch.

Fluid connection to the hydraulic machine is provided through the pipe-threaded outlet- inlet passages 76 and 78 which communicate with the annular chambers 30 adjacent the rotary valve 42 substantially as shown in Fig. 2. A fluid passage 80 communicates with the annular chambers 30 adjacent the rotary valve on the opposite side from the outlet-inlet passages. As the hydraulic device can rotate in either direction, either passage 76 or 78 can act as an inlet for the hydraulic fluid.

In operation there is a certain amount of seepage of hydraulic fluid across the flanges 26 and 28 WhlCh accumulates in the open spaces at either side of the main housing 10 within the end plate 60 and drive shaft supporting bell 62. To confine this fluid within the housing, a rotary pressure seal 82 is provided on the drive shaft 70. After these spaces and the holes 22 through the rotors become filled with fluid, it has been found that the pressure in the housing could gradually build up to approximately half the line pressure, but no greater, on the high pressure side of the hydraulic system. To confine the fluid at these pressures would require the rotary pressure seal 82 to be elaborate and expensive, and would also require the weight and strength of the housing to be materially increased inasmuch as the hydraulic pressures occurring in the normal use of the machine go to many hundreds of pounds per square inch.

To eliminate the building up of any appreciable pressure within the'housing, spring-loaded relief valves 84 and 86 are provided in the main housing, one valve communieating with each one of the outlet- inlet passages 76 and 78. When the pressure of the fluid within the housing spaces exceeds the combined force of the relief valve spring and the pressure within the low pressure side of the hydraulic system, one relief valve opens, permitting any excess fluid collected within the housing spaces to return to the hydraulic fluid system to thereby substantially equalize the pressure inside the housing with that at the low pressure side of the machine. Because either passage 76 or 78 may be the low pressure side of the machine, a relief valve is provided in each passage.

Assembly of the hydraulic machine is The rotors are positioned at opposite sides of the valve 42 with the body of the valve between the flanges of the rotors, and the valve and rotors are moved together into the housing bores with the cover plate 60 removed. The rotors are axially located from the rotary valve 42, which is in turn held against axial movement in one direction by the shoulder provided at the base of the counterbore 46 and in the other direction by the bearing cap 50 which is bolted into position after the valve and rotors are in operative position. The drive shaft supporting bell 62 and the cover plate 6% can be assembled or disassembled by virtue of the tongue and groove connection 72 between the drive shaft and the rotary valve trunnion 44, without affecting the assembly of the rotors and rotary valve within the main housing block 10.

In operation, the hydraulic machine described can function either as a hydraulic pump or a hydraulic motor and is completely reversible. When serving as a motor, for example, high pressure fluid entering inlet passage 76, if the rotors and associated valve are in the position shown in Fig. 2, passes around the annular chamber provided in bore 12 through the passage 89, where it comes in contact with the vane 36 and in so doing turns the rotor 18. The rotor 18 in rotating, through the associated gearing, turns the rotary valve 40 and the rotor 16. By the time the rotor 18 rotates around to the point where fluid escapes past the vane 36 into the outlet passage 78, the vane 36 on the rotor 16 has reached the position where it seals off the annu ar chamber 3? associated with it against further flow of fluid from the intake passage 76. At this time, the pressure of the fluid in the intake passage 76 engages the vane to rotate the rotor 16 around to a point where the fluid can flow into the passage 80 and thence into operative engagement with the vane 36 on the rotor 18. In this manner, the cycle of operation is completed, and this cycle is continuously repeated with the fluid pressure acting alternately on the rotors to provide a continuous non-pulsating drive to the drive shaft 70.

When the hydraulic machine of the invention is used as a pump, the shaft '70 is driven and the operation of the apparatus is the reverse of that just described, as will be understood.

Figs. 5 and 6 disclose a modified form of the invention in which the hydraulic machine can be used as a motor to supply traction power to a vehicle wheel. Construction and operation of this modified form is essentially the same as heretofore described. However, in the interest of more rugged or heavier horsepower construction, the rotors are rotatably supported within the housing bores by means of roller bearings 91. The vane 92 on each rotor is made somewhat differently, being in the form of a bar or blade which is secured in position in the annular space between the flanges 94 of the rotors by means of dowels 96. The power take-off is in the form of a ring gear 98 which is secured to the wheel hub 100 by means of an internal spline indicated at 102. The housing of the motor is provided with projecting lugs 104 from which the complete wheel and motor assembly can be supported by parallel linkage and associated spring means from a vehicle frame (not shown).

It will be recognized that the objects of the invention have been achieved by providing a hydraulic machine which is completely reversible and non-pulsating, which can be used either as a pump or motor, which is rugged and compact in design but light in weight, which is comparatively simple and. inexpensive to manufacture and maintain, and which is capable of operating with high efiiciency under high fluid pressure and high mechanical torque over long periods without attention or repair.

While in accordance with the patent statutes, one best known embodiment of the invention has been illustrated and described in detail, it is to be particularly understood quite simple.

that the invention is not limited thereto or thereby, but that the inventive scope is defined in the appended claim.

We claim:

In a rotary hydraulic machine comprising a main housing member having spaced cylindrical bores therethrough, a rotor having a pair of spaced flanges defining an annular recess therebetween extending around the periphery of the rotor, said rotor being received in one of said bores, said spaced flanges having cylindrical surfaces which in an axial direction are relatively wide with respect to said annular recess, said wide cylindrical surfaces being journaled in one of said spaced cylindrical bores of said main housing member and in direct sealing contact With said one bore, a vane carried by said rotor and extending axially across the annular recess thereof and extending radially to seal with the bore, and a rotary 6 valve body journaled in another of said cylindrical bores of said main housing member for substantially rolling contact with said rotor, said valve body having a recess to clear said rotor vane and said rotor and valve being geared together.

References Cited in the file of this patent UNITED STATES PATENTS 2,525,619 Roth Oct. 10, 1950

Images