US2150347A

US2150347A - Compressor

Info

Publication number: US2150347A
Application number: US121056A
Authority: US
Inventors: Clarence S Sorensen
Original assignee: Individual
Current assignee: Individual
Priority date: 1937-01-18
Filing date: 1937-01-18
Publication date: 1939-03-14
Anticipated expiration: 1956-03-14

Description

March 14, 1939. c. s. SORENSEN COMPRESSOR Filed Jan. 18, 1937 3 Sheets-Sheet l March 14, 1939. c s soR s 2,150,347

COMPRESSOR Filed Jan. 18, 1957 3 Sheets-Sheet 2 March 14, 1939. s SQRENSQJ 2,150,347

COMPRESSOR Filed Jan. 18, 1957 s Sheets-Sheet 3 Patented Mar. 14, 1939 UNITED STATES PATENT orrlce COMPRESSOR Clarence S. Sorensen, Los Angeles, Calif. Application January 18, 1937. SerialNo. 121,656 6 Claims. (01. 2364-17) This invention relates to fluid handling machines and relates more particularly to compressors. A general object of the invention is to provide a practical, improved and very eflicient compressor of the rotary type.

Another object of this invention is to provide a compressor or like mechanism of the rotary type and embodying reciprocable pistons that is characterized by having all its rotating parts dynamically balanced whereby the inertia and forces set up by the rotation of the parts are all equalized or balanced.

Another object of this invention is to provide a compressor of the character mentioned in which the rotating cylinder block and the eccentric rin for effecting operation of the pistons in the cylinders are both dynamically balanced and are individually supported for rotation to rotate with a minimum of friction and expenditure of power.

Another object of this invention is to provide a compressor of the character mentioned embodying novel and very effective means for rotatably supporting the ring in eccentric relation to the axis of the cylinder block.

25 Another object of this invention is to provide a compressor of the character mentioned embodying novel and very simple means for associating the pistons with the eccentric ring that may allow relative turning between the ring and the pistons and yet retain the pistons in their proper relation to the ring.

Another object of this invention is to provide a compressor of the character mentioned embodying a practical and long wearing valve means for controlling the inlet and discharge of the fluid.

Another object of this invention is to provide a compressor of the character mentioned in which the valve means may be easily and quickly regulated. 40 Another object of this invention is to provide a compressor of the character mentioned embodying simple means for releasably connecting the main compressor shaft with the shaft of a motor or other power unit that permits the easy disconnection of the motor from the compressor proper.

The various objects and features of my invention will be fully understood from the followin detailed description of typical preferred forms and applications of the invention. throughout which description reference is made to the accompanying drawings, in which:

Fig. 1 is a central longitudinal detailed sectional view of the compressor provided by this invention. Fig. 2 is a reduced end view of the compressor. Fig. 3 is a fragmentary'vertical detailed v sectional view taken as indicated by line 3-3 on Fig. 1. Fig. 4 is a transverse detailed sectional view illustrating the cylinder block and the pistons. Fig. 51s a fragmentary side elevation with portions broken away to illustrate an alternative or modified mounting for the eccentric ring. Fig. 6 is a fragmentary vertical detailed sectional view taken as indicated by line 6-6 on Fig. 5 and Fig. '7 is a transverse sectional view of the connection between the main shaft and the motor shaft taken as indicated by line 1-1 on Fig. 1.

The compressor provided by this invention includes, generally, a housing II), a shaft I extending through the housing It, a cylinder block I2 on the shaft I, pistons i3 operable in the cylinders C of the block l2, a ring |4 cooperating with the pistons l3 and supported in the housing III in eccentric relation to the cylinder block I2 to cause operation of the pistons, regulable valve means l5 for controlling the flow of fluid to and from the cylinders C and a power unit or motor l6 driving the compressor shaft I.

- The housing I0 is a hollow structure containing the cylinder block l2 and the ring l4 and supporting the shaft H and the valve means I5. The housing In in the preferred form of the invention includes a generally cylindrical main section l1 closed at one end by a bolted on plate l6 and having an end wall I! at its other end. The end portion of the housing section [1 adjacent the end wall I9 is reduced in diameter or height as best illustrated in Figs. 1, 5 and 6. The housing of the motor I6 is secured to the end wall l9 as will be hereinafter described. A comparatively large opening 26 in the end wall I! is closed by a plate 2|. The plate 2| may be secured to the end wall [9 by suitable bolts-or screws 22. The housing section I1 may. have suitable base or standard flanges 23. An annular and substantially cylindrical flange 24 projects inwardly from the end wall IS. The upper portion of the flange 24 may merge with the upper wall of the housing section II. The flange 24, the opening 20 and the plate 2| are oiiset or eccentric with relation to the longitudinal axis of the housing Ill. The housing i6 is entirely closed and may contain a suitable lubricant.

,The shaft ll carries or drives the cylinder block I2 and extends longitudinally and centrally through the housing It. The shaft extends through an eccentric opening 25 in the plate 2| and projects from the housing It for connection with the shaft of the motor. l6. A

tion of the shaft II. The bearing 26 may surround a reduced portion of the shaft II and may take end thrusts from the shaft in one direction. A ring 28 is secured in the opening ,25 and engages against the outer end of the bearing 26. The shaft II extends completely through the housing I6 to project through the end plate I8. In accordance with the invention the end plate [8 has a central tapered opening 29 receiving a correspondingly tapered block 36 which in turn is provided with an opening 3| freely receiving the shaft II. The shaft II has a reduced end portion rotatably supported by a bearing 32 in the block 3!]. The bearing 32 may engage against a shoulder 33 and a nut 34 on the shaft II to take end thrusts from the shaft. The block 30 carries a suitable cap 35 which closes the outer end of its opening 3| and retains lubricant for the bearing 32. The block 30 is an element of the valve means I5. At present it is believed suflicient to state that the valve block 30 is secured to the end plate I8 by studs or screws 36 threaded into openings in a hub or boss 31 on the end plate I8. It will be noted that the compressor shaft II is rotatably supported at its opposite ends by the

bear ings

26 and 32.

The cylinder block i2 is the principal rotating element of the compressor. The block I2 is preferably an integral member as illustrated. The cylinder block I2 rotates with the shaft II and is suitably fixed or keyed to the shaft adjacent the inner side of the end plate I8. A central opening 38 in the cylinder block l2 receives the shaft II. In the arrangement illustrated the shaft II has longitudinal grooves 39 receiving threaded set pins 40 on the block I2 which fix the cylinder block to the shaft. The cylinder block I2 is bored to have the cylinders C. The cylinders C are radial openings being radial with respect to the longitudinal axis of the shaft II. It is a feature of the invention that the cylinder block I2 is dynamically balanced. Further, the block I2 is preferably light in weight and formed to remain as cool as possible. The cylinder block I2 is provided with a multiplicity of circumferentially spaced parts 4| projecting radially outward relative to its axis of rotation. The radially projecting parts M are equally or symmetrically spaced and the cylinders C are provided in the parts M. In the case illustrated the'ra'r six equally spaced cylinder parts 4i each provided with a cylinder C. The cylinders C extend into the outer ends of the cylinder parts 4| being in the nature of cylindrical sockets or bores closed at their inner ends and open at their outer ends to receive or carry the pistons I3. The cylinders C, of course, are of equal size. It will be noted that the cylinder block I2 is a simple light-weight member and is diametrically balanced so that its rotation imposes a minimum stress on the shaft II and the shaft bearings.

The pistons I3 are provided to reciprocate in the cylinders C to pump or compress the fluid handled by the machine. In practice the pistons I3 may be simple structures as illustrated. The pistons I3 are closed at their inner ends by integral imperforate heads and suitable rings 42 are provided on the pistons I3 to slidably seal with the walls of the cylinders C. The outer ends of the pistons I3 are closed by plug-like heads 43. The heads 43 have radial annular flanges 44 opposing the outer ends of the pistons I3. In accordance with the invention the heads 43 are adjustably secured to the pistons I3. The heads 43 are threaded into the pistons I 3 and laminated shims 43 are provided between the flanges 44 and the outer ends of the pistons I3. The pistons I3 and their heads 43 may be adjusted with respect to one another by varying the thickness of the shims 45. Shoes 46 are provided on the piston heads 43 for cooperating with the ring I4. The shoes 46 may be integral with the piston heads 43 and have curved convex outer surfaces 41 for cooperating with the interior of the ring I4 as will be subsequently described.

The ring I4 is provided to cooperate with the shoes 46 of the pistons I3 to effect the operation of the pistons. The active portion of the ring I4 surrounds the cylinder block I2 while the supporting portion of the ring I4 extends into the internal housing flange 24 to be supported therein. The ring l4 includes a cylin drical tubular section 48 surrounding the cylinder block I2 and having a finished cylindrical internal surface 49 for slidably cooperating with the surfaces 41 of the shoes 46. The ring I4 further includes a disc-like section 50 having a cylindrical tubular sleeve 5I extending axially into the housing flange 24. The ring section 48 may be attached to the section 50 by suitable screws 52.

As described above, the flange 24 is eccentric relative to the axis of the housing I and the sleeve is rotatably supported in the flange 24 so that the ring I4 is rotatable about an axis parallel with and spaced from the axis of rotation of the cylinder block I2 and the shaft II. In the construction illustrated in detail in Fig. 1 the sleeve 5I is rotatably supported by an antiiriction bearing 53 in the inner portion of the flange 24 and a somewhat smaller bearing 54 in the opening 23 in the housing end wall I9 at the outer end of the flange 24. The inner end portion of the flange 24 may have an inwardly extending rim provided with a groove 56 carrying the bearing 53. The bearings 53 and 54 may cooperate with

shoulders

51 and 58, respectively, of the sleeve 5| to receive end thrusts from the ring I4.

It will be observed that the ring I4 just described is supported in the housing I 0 for free rotation and has its cylindrical internal surface 43 engageable by the shoes 46 of the pistons I3 which engagement may cause rotation of the ring I4 when the cylinder block I2 is rotating. It is believed that it will be apparent how the ring I4 having its axis of rotation spaced from the axis of rotation of the cylinder block I2 cooperates with the piston shoes 46 to successively cause inward movement of the pistons in the cylinders. The outward movement of the pistons is caused by centrifugal force or fluid pressure in the cylinders; or both. It will be seenthat by varying the thickness of the shims 45 the innermost positions of the pistons I3 relative to the bottoms of the cylinders C may be adjusted or regulated as found most desirable. It is important to note that the above described ring I4 is symmetrical and dynamically balanced and rotatably supported in such a manner that it imposes a minimum of stress on the bearings and housing parts.

The invention provides simple means for loosely connecting the pistons I3 with the ring I4 to prevent the pistons from falling inwardly in the cylinders C when the operation of the compressor is suspended. This means includes a hook-like I inders C.

scoping portions of the boss 31- a I and has communication with the amal'port-;6l'.- The port 62 is curved concentric with the axis of r the shaft II and is of substantial length and member 18 attached to the outer end of each piston shoe 48 by a screw or bolt 18. Themembers 16 extend outwardly at the end of the ring section 48 and each has a finger 'll projecting axially at the outer periphery of the ring section. The members 15 do not engage the end of the ring section 48. The fingers 11 are normally clear of the periphery of the ring section 48 but may engage aga nst the ring section to prevent the pistons l8 from falling or moving inwardly in the cylinders C when the compressor is stopped.

The valve means I6 is provided to control the admission and exhaust of the fluid from the cyl- It is a feature of the invention thatthe valve means l5 includes a minimum number of simple parts. The means I6 includes the valve block 30 mentioned above. The tapered block 36 is tightly clamped in the tapered opening 29 by the studs or bolts 36" to tightly seal with the wall of the socket. A sealing washer or ring 59 may be clamped between opposing" shoulders of the block 30 and the socket 28 to assure aperfect seal. A suction or inlet line 68 communicates with a port 6| extending i5ito theeboss' 31 of the end plate l8. gi urged ocircuhiferebz. tial port 62 extends-througlilfieengagingte radial extent so thatthe fluid;;flowingthere'- through serves to cool the r8 widtfifand curved concentric port 6311') rd'fi ced length is provided in the inner face64 of the valv block 38 and has extensive communicationwith; the port 62. The port 63 is preferably slightly less than 180 in circumferential extent. The inner surface or face 64 of the valve block 30 is finished and smooth. Webs 65 may extend through the port 62 to connect the parts of the block 38 separated by the port.

An outlet or discharge line 66 communicates with a radial port 61 extending into the boss 31. The port 61 continues through the boss 31 and the block 38 to have its inner end at the inner surface 64 of the valve block. The inner end of the port 61 is..of' the same widthas the port 83 and has the same curvature as the port 63. The discharge port'GT is somewhat shorter than the inlet port'63 being only substantially-90 in circumferential extent at the inner surface 64 of the valve block 30. The discharge port 61 does not occur in opposite relation to the port 63 but has one endin spaced adjacent relation to an end of the port 63. This relationship is clearly illustrated in Fig.3 of the drawings.

The valve means l5 further includes a valve block or member 68 arranged in a socket 68 in the cylinder block ii to have its outer end oppose the inner surface 64 of the block 38. In accordance with the invention the member 68 has limited axial movement in the socket 69 but is made to turn with the cylinder block l2. One or more pins 10 project from the inner wall of the socket 69 and slidably fit openings II inthe member 68 to cause the member to turn with the cylinder block. Spring means is provided to urge the member 68 outwardly to have its outer end in sealing contact with the surface 64 of the valve block 30. In the preferred construction illustrated a plurality of spaced bores 12 is provided in the bottom of the socket 68.. The bores 12 receive coiled springs 13 which engage against the inner end of the valve member 68 to hold the member outwardly so that its outer and seals against the surface 84 of the block 88. Ports 14 extend from the inner ends of the cylinders C to the outer face or end of the valve member 68. A single port I4 communicates with each cylinder C. The ends of the ports 14 at the face of the block 68 are in the same rotative positions as their respective cylinders C and are in a circumferential series to successively register with the ports 63 and 61 in the valve block 80. v

The rotative positions of the ports 63 and 61 in the face 64 of the valve block 30 are related to the eccentricity of the ring 14 in such a manner that the port I4 of a cylinder C communicates with the'inlet port 63 during the out stroke of the piston [3 in the cylinder and comes into communication with the outlet port 81 when the piston is in the major final portion of its inward stroke after the gas has been compressed the desired extent. The invention provides novel and very effective means for regulating the valve 'means |5, th p1s foradjusting the rotative posi- 1 the desired operationof the machine. the bipola The valve adjusting means includes an abutment 18 on the block- 30. The abutment 18 may project outwardly from the block 30 adjacent the boss 31. Spaced lugs 18 project outwardly from the end plate l8 to be in spaced relation from the opposite sides of the abutment I8. A screw is'threaded through an opening in each lug l9 and the screws are adapted to engage against the abutment 18. The screws 88 engaging against the abutment 18 normally prevent turning of the valve block 30 and thus retain the valve block in its adjusted position. Lock nuts 8| may be provided on the screws 88 to set the screws in their adjusted positions. The openings 36 in the block 30 which receive the studs 36 are in the nature of slots or curved openings whereby the block 30 may have limited turning movement when the nuts 36'' onthe studs 36 are loosened.

It will be apparent how the valve block 30 may be turned or adjusted following the loosening of the nuts 36 by backing off one screw 88 and tightening in the other screw 80. After such adjustment the lock nuts 8| may be employed to lock the screws 88 in place and the nuts 86 may be tightened down. Turning or adjustment of the valve block 30 by the adjustment means just described changes the rotative position of the ports 63 and 61 and therefore changes the times during which the cylinder ports 14 communicate with the ports 63 and 61. The ports 63 and 6'! are, of course, related or spaced so that the cylinder ports 14 are out of communication with both of them at the ends of the piston strokes.

The motor I6 is provided to drive or rotate the compressor shaft II. The particular motor "5 illustrated is a sealed induction motor comprising a housing 83, an armature 84 and a field 85. The present invention is not primarily concerned with the armature 84 of the field 85 of the motor. The armature 84 is carried by a shaft 86. The motor housing 83 is substantially cylindrical and is entirely closed or sealed. An integral wall 81 closes the outer end of the housing 83. A suitable bearing 88 is carried in a socket 88 in the housing wall 81 to rotatably support the end of the motor shaft 86. The inner end of the motor housing 83 is connected with the end IQ of the compressor housing III by a flange and bolt concompressor. ,A manifold 92 extends around the motor housing 93 and is adapted to-carry water orother cooling medium to cool the motor. The

cooling medium may be supplied to and carried I from the manifold 92 by suitable lines as.

' The invention provides an effective readily re;

leasable connection between the compressor shaft l I and the motor shaft 86. The motor shaft 86 is provided with an axial socket 55 in its inner end which receives the end portion of the compressor shaft ii. The socket 94g-is provided with longitudinal splines 95 which cooperate with grooves 96 in the compressor shaft I I. The shaft II may have a reduced pilot portion 91 fitting a correspondingly reduced portion of the socket 94. The shafts II and 86 may be quickly connected by sliding the shaft 96 onto the end portion of the shaft II so that the splines 95 are received in the grooves 96. The splines 95 cooperating with the grooves 96, of course, transmit rotation between the shafts. The connection just described permits the entire motor I6 to be easily removed from the compressor without disturbing any parts of the compressor. In the event that the motor I6 requires replacement or repair the flange and bolt connection 99 may be released whereupon the entire motor IG may be bodily moved away from the housing I9. The splines 95 slide out of the grooves 99 allowing the shaft 86 to freely disconnect from the shaft II. In this manner the motor I6 may be disconnected from the compressor proper without disturbing any parts of the compressor.

Figs. 5 and 6 of the drawings illustrate a form of the invention embodying an alternative or modified means for rotatably supporting the ring I4. In this form of the invention the tubular internal flange 24 of the housing I is provided with a plurality of pairs of spaced cars 98. The cars 98 project inwardly in the flange 24 and are spaced apart axially with respect to the axis of the machine. The pairs of cars 98 are preferably equally spaced about the interior of the flange 24. A shaft 99 is carried by each pair of ears 98. The shafts 99 may be pressed or otherwise secured in openings I09 in the cars 98 and are parallel with the axis of the ring sleeve Suitable anti-friction bearings IDI are carried by the end portions of the shafts 99 to have supporting cooperation with the sleeve M. The bearings IIlI may engage against the outer sides of the ears 99 and shoulders I92 and I 93 on the sleeve 5| for the transmission of end thrusts. It is believed that it will be apparent how the spaced sets or pairs of anti-friction bearings IIlI support the ring I4 for free independent rotation.

It is believed that the operation of the compressor will be understood from the foregoing detailed description. The motor I6 drives or rotates the shaft II which in turn rotates the cylinder block I2. The cylinder block I2 is symmetrical and dynamically balanced so that its rotation imposes a minimum of stress on the shaft II and its bearings. As the cylinder block I2 rotates within the eccentrically disposed ring I4 the shoes 46 cooperating with the interior of the ring cause the pistons I3 to be successively moved inwardly in the cylinders C. The centrifugal force on the pistons I3 and perhaps the fluid pressure in the cylinders C successively move the pistons outwardly in the cylinders C. In actual operation the members I5 do not cooperate with the ring section 48 to cause the outward movement of the pistons in the cylinarcane? ders. When operation of the compressor Is commenced the engagement of the shoes 48 with the internal surface 49 of -the ring I4 may be in the nature of a sliding engagement and the ring may tend to remain stationary. However, the engagemerit of the. shc'eswith the interior of the ring it will ultimately result in rotation of the ring it with the cylinderblock-l2a Howevenas the ring- I9. is independently's'upportedfor rotation about an axisspacedfrom the axis of rotation of the cylinder block I2 its operation remains the same irrespective of whether it rotates or remains stationary. 1 The ring I4 is a symmetrical dynamically balanced structure and its rotation imposes a minimum of stress and strain on its bearings 53 and 54 and the housing parts.

The valve member 68 turns with the cylinder block I2 and the cylinder ports 14 successively move across the inlet port 63 and discharge port 61 in the end face 64 of the block 39. As described above, the ports 63 and 61 are related to the position of the ring I4 so that the cylinder ports I4 are in communication with the inlet port 63 during substantially the entire out strokes of the pistons I3 and come into communication with the discharge ports 61 when the pistons I3 have completed a. portion of their inward strokes and remain in communication with the discharge port 61 during the remainder of the stroke so that the fluid under pressure is discharged through the port 61 and the line 56. The screws 89, may upon loosening of the nuts 36 and 8I be employed to change the rotative position of the valve block and thus adjust the rotative position of the ports 63 and 61 to properly regulate the action of the compressor.

It will be noted that the valve means I5 embodies a minimum number of working parts. The member 68 engages against the surface 64 of the block 30 and is held in sealing contact therewith by the springs I3. The member 68 and the block 30 constitute the only engaging and moving parts of the valve means I5. The compressor shaft II is dependably supported at its opposite ends by the

bearings

26 and 32 while the ring I4 is effectively supported at spaced points by the bearings 53 and 54. Thus the principal rotating elements of the compressor are efiectively supported by sets of spaced bearings. The compressor is compact and yet has a substantial capacity. There are a minimum of wearing and working parts embodied in the machine. The shims 45 constitute an easy means of regulating contact between the pistons I3 and the ring I4 and for adjusting the clearance of the pistons in the cylinders 0.

Having described only typical preferred forms and applications of my invention, I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art or fall within the scope of the folowing claims Having described my invention, I claim:

1. A mechanism of the character described including a housing, a shaft extending through the housing, a tubular internal flange formed on the wall of the housing surrounding the shaft in spaced relation thereto, a cylinder block in the housing fixed to the shaft and having cylinders, pistons operable in the cylinders, valve means for controlling the fluid fiow to and from the cylinders, a ring surrounding the block for cooperating with the pistons, a sleeve on the ring extending into said flange, an annular series of with the said inlet circumferentially spaced bearing shafts in the said flange, and anti-friction hearings on the bearing shafts cooperating with the sleeve to support the ring for rotation about an axis spaced from the axis of the cylinder block.

2. A mechanism of the character described including, a housing having spaced opposite end walls, a rotatable shaft extending through the housing, bearing means carried by said end walls for rotatably supporting the shaft, a rotor fixed to the shaft in the housing and having radial cylinders and having cylinder ports communicating with the cylinders, pistons in the cylinders, a ring rotatably supported in the housing in eccentric relation to the shaft and cooperating with the pistons, two elements one a block supported by the housing and having an inlet port and an outlet port both extending to the exterior of the housing, the other a part carried by the rotor and having ports communicating with the cylinder ports and adapted to register with the said inlet during the out strokes of the pistons and adaptedto register with the said outlet port during only portions of the in strokes of the pistons, both of said elements being in surrounding relation to .the shaft, and means for urging one element against the other.

3. A mechanism of the character described ineluding, two elements one a housing, the other a rotating rotor having radial cylinders, pistons in the cylinders, a ring rotatably supported in the housing in eccentric relation to the shaft and cooperating with the pistons, a block supported by one of the elements for limited turning movement and having an inlet port and an outlet port the outlet port being of less extent than the inlet port at a face of the block, the rotor having ports communicating with the cylinders, a member carried by the other element and having ports communicating with the cylinder ports, the member being pressed against said face so that its ports are.adapted to successively register and outlet ports, and means for regulating the rotative position of the said block, the said means including a fixed abutment, and screw ports on the said block cooperating with the abutment.

4. A of the character described includin a housing, a rotatable shaft extending through the housing, a rotor fixed to the shaft in the housing and having radial cylinders, pistons in the cylinders. a ring rotatably supported in the housing in eccentric relation to the shaft and cooperating with the pistons; a block supported by the housing for limited turning movement and having an inlet port and an outlet port, said inlet and outlet ports extending to the exterior of the housing the rotor having ports communi-' eating with the cylinders and adapted to successively register with the said inlet and outlet ports, and means for regulating the rotative position of the said block, the said means including an abutment on the housing, lugs on the said block at opposite sides of the abutment and screws on the lugs cooperating with the opposite sides of the abutment.

5. A mechanism of the character described including, a housing having an end wall with an opening, a rotatable shaft extending through the housing, a rotor 'fixed to the shaft in the housin and having radial cylinders, pistons in the cylinders, a ring rotatably supported in the housing in eccentric relation to the shaft and cooperating with the pistons, a block supported in said opening and having an inlet port and an outlet port, said ports extending to the exterior of the housing, and a part carried by the rotor to have part having ports inders and adapted to sucessively communicate with said inlet and outlet ports, the said inlet port being of large circumferential extent whereby the fluid therein serves to cool the block and the adjacent parts. 6. A mechanism of the character described including, a housing, a rotatable shaft extending through the housing, a rotor fixed to the shaft in the housing and having radial cylinders, pistons in the cylinders, a ring rotatably supported in the housing in eccentric relation to the shaft and cooperating ,with the pistons. the housing having a tapered socket co-axial with the rotor, a tapered block the block in the socket and allowing turning of the block, the block having an inlet port and an outlet port, a spring-urged member carried by the rotor and with the block, the rotor and member having ports communicatin with the cylinders and adapted to successively communicate with the inlet and outlet ports, and means normally holding the block against tuming and operable to turn the block.

. a soanusnu.

in the socket, means securing-