US1822064A

US1822064A - Compressor

Info

Publication number: US1822064A
Application number: US463134A
Authority: US
Inventors: Clarence S Sorensen
Original assignee: Individual
Current assignee: Individual
Priority date: 1930-06-23
Filing date: 1930-06-23
Publication date: 1931-09-08
Anticipated expiration: 1948-09-08

Description

Sept, 8, 1931. c. s. soRENsEN 1,322,064

' coMREssoR Filed'June 23, 1930 2 Sheets-Sheet l LSB . Spt. V8, 1931. C` SQRENSEN 1,822,064

COMPRESSOR Filed June 25, 193D 2 Sheets-Sheet 2 l ,aff j Patented Sept. 8, 1931 l UNITED-.STATES PATENT ori-ICE CLARENCE S. SORENSENOF LOS ANGELES, CALIFORNIA comrims'son Application filed June 3.1930.` serial No. 463,14.

This invention relates to a pump or compressor and itis a general object .of the invention to provide an efficient and practical compressor suitable for handling various fluids.

An object of the invention is to provide an j simple in its construction and operation and does not embody parts that are noisy in operation and quickly Worn.

Another object of the invention is to pro.`

yide a compressor that is operable to discharge fluid against ay comparatively high pressure in a line or Ireservoir Without causing a back pressure on the pistons.

It is a further object of this invention to provide a compressor of the character mentioned that is particularly compact and sturdy inconstruction and embodies but few simple parts. j Another object of the invention is to provide a valve construction for a rotary com- 1 pressure which is effective in holding pressureand which .automatically takes up wearthat may occur between the working parts.

Other objects and features ofmy invention will be best and more fully understood from 4 the following detailed description of a typical form and application of the invention, throughout which description reference is had to the accompanying drawings, in which Fig. 1 is a longitudinal detailed sectional view ofI the compressor provided bythe present invention, being a vView taken between the inlet and outletl ports. Fig.-2 is` a longitudinal detailed sectional view of a portion of the compressor taken as indicated by line 2-2 iman- Fig.' lfiilusimang the inlet and' outlet ports in communication with the cylinders. ig. 3 is a reduced transverse detailed sectional view taken substantially as indicated by line/3 3 on F ig. )1, and Fig. 4 is a transverse detailed sectional view, beinga view taken substantially as indicated by line on Fig. 1.

The mechanism provided by the present invention includes, generally, a stationary housing 10, a rotatable cylinder block 11 mounted within the housing 10, pistons 12' operable in cylinders 13 in the block 11, a drive ring v14 mounted within the housing l0 for causing reciprocation ,of the pistons 12, a

driveshaft 15 for driving orrotating the'y cylinder block 11 and the drive ring 14, and means 16 for controlling the'low of fluid tol and from the cylinders 13.

The housing 10 includes a body 17, a head 18 closing the inner end of the body 17, and a f headf19 closing the outer end offthe body.

'The body 17 is substantially cylindricalv and is made 1hollow or tubular to hold or carry the Various parts of the mechanism. The heads 418 and 19 may be detachably secured to the body 17 by suitable cap screws 20 and a servlice opening21 may be provided inthe body 17 so ithatthe' interior of the housing may be readily accessible. The opening 21 may be closedby a removable cover plate 22. A jacket -23 may be provided around the body 17 tov provide a space A for containing a suitable cooling medium.

`The cylinder block 11- is rotatably mounted in the body 17 of the housing adjacent the outer head 19. In the preferred construction the cylinder block 11 is rrotatably mounted on an inwardly extending hub or projection 24 on the inner side of the head 19. A suitable anti-friction bearing 25 may rotatably support the cylinder block 1 1 on theprojection 24. fr

The block 11 is provided withy a plurahty of axial cylinders 13 for carrying the pistons 12. vThecylinder openings 13 are symmetrically arranged or` equally spaced around the central axis lof the mechanism. There may be any suitable number of cylinder openlngs 13. In the particular form of the invention illustrated there are fur equally spaced as.v

A in the opening 30.

ing projections 27 fitting into the openings 13.

The inner ends of the cylinders 13 are open.

The pistons 12 are mounted for reciprocation in theiseveral cylinders 13 and are operable by the drive ring 14 during operation of the mechanism. The pistons 12 are provided with sealing rings 27u to frictionally engage Vthe Walls of .the cylinders 13.

The drive ring 14 is rotatably mounted within .the housing 10 adjacent the outer head 18. The drive ring 14 is mounted 'to rotate in a plane tilted or angularly disposed relative to a plane perpendicular .to the cen. tral longitudinal aXis of the compressor. AThe drive ring 14 surrounds the sha-ft 15 and is rotated or driven by the shaft as will be hereinafter described. In Vaccordance with the preferred. construction the ring 14 is rotatably supported on a shoulder 28 on the inner side of the head 19 through a suitable anti-friction bearing 29. The bearing 29 supports the ring 14 on the shoulder 28 (so that it is rotatable in a tilted plane.

opening 30 in the head 18 to project into the housing 10. A suitable anti-friction bearing 31 may be arranged in an opening or bore 32 inthe head 18 to rotatably support the shaft A thrust or retaining collar 33'mayvbe provided on the shaft 15 to engage the bearing 32. A cap 34 may be provided on the head 18 to encase the bearing 31 and adjacent parts and` to carry a lubricant for lubricating the bearing. A suitablepacking gland 35 may be provided in connectionwith the cap 34 to seal around the Lshaft 15. The, cap 34 may be jacketed to have a space 36 for carrying a suitable cooling medium. The inner end of the shaft 15 extends into an opening in the cylinder block 11 and afsuitable key 37, or the like, may be provided to rotatably connect the shaft and cylinder block.

A suitable drive connection is provided between the drive ring 14 and the shaft 15. In the preferred forni of the invention a universal drive is p rovided between the shaft and the ring 14 and includes a collar 40 surrounding the shaft 15 and pivotally carried on pins 41 projecting from diametrically opposite sides of the shaft. The collar is provided with diametrically opposite pins 45 extending into openings in the drive ring 14.

Connecting rods 46 are provided to operatively connect the pistons 12 with the drive ring 14 so'that the pistons 12 are recipro- ,'Ihe driveshaft 15 is provided.y to drive. or. `rotate the cylinder block 11 and the drive .cylinder block 11.

cated in the cylinders 13 upon rotation of the'block 11 and drive ring 14. Spherically curved heads 47 are provided on the rods 46 to seat in sockets 48 in the pistons and retaining members 49 are provided to retain the heads in the sockets. rlhe drive ring ends of the connecting rods 46 are provided with splierically curved heads 50 seating in sockets 51 in bearing blocks 52 carried by the ring 14.

The construction 'thus far described may be varied considerably without departing from the broader principles of the invention.

The means 16 for controlling the flow of fluid to and from the cylinders 13 is'an iniportant feature of the invention. IVith the incorporation of the means 16 in the compressor it is operable to deliver or discharge fluid under pressure into a line or reservoir carrying fluid under comparatively high pressure Without causing a back pressure ou the pistons 12. ,c

Y The means 16 includes a valve ring 60 having ports 61 communicating with the cylinders 13 Yand operable to cooperate with an intake port 62 and a discharge or outlet port 63. In the preferred form of the invention the valve ring is mounted to operato or rotate with'the'icylinder block 11 to cooperate with stationary intake and discharge ports in the head 19. The valve ring 60 is slidably mounted in an opening 64 in the The ring 60 is slidable longitudinally in the bore or opening 64 and is connected with the cylinder block 11 to i rotate with the block. In the Vparticular form of the invention illustrated pins 65 project from the cylinder block 11 into notches 66 in the ring 60 to prevent rotation 4of the ring relative to the cylinder block.

JYcrate with a conical or beveled shoulder or seat 68 on the head 19. The beveled outer end of the valve ring 60 and the seat 68 are smoothly finished to effectively seat together. In accordance with the invention means is provided for holding the seat ring 60 in effective engagement with the seat 68 and to provide for compensating for the wear between the seat and ring. A helical spring" 69 is ary." and ranged under compression between the botme tom or inner end of the opening 64 and the valve ringar60 to urge the beveledouter end of the valve ring into effective seating engagement with the shoulder 68.. f

The ports61 in the valve rlng 60 register with ports or openings in the cylinder f block 11 communicating with the vcylinder openings13 adjacent their inner ends. The

pins 65 h'old the valve ring 60 in a position k I where the ports 61 are always in register with the openings 70. The ports 61 extend to the beveled outer end of the valve ring Where they are adapted to cooperate with the inlet port 62 and the outlet port 63 in the head 19. The

ports

62 and 63 in the stationary element or head 19 aie related to the space d ports 61 in the valve ring so that they pass fluid into and out of the cylinders 13 during reciprocation of the pistons 12.

The inlet port 62 and the outlet port 63 extend inwardly from the exterior or outer side of the head 19 to the beveled seat 68. The outer portions of the

ports

62 and 63 at the exterior of the head 19 may be screw threaded to receive suitable fluid conduits. The inner portion of the inlet port 62 is elongated so that it, extends around or along the beveled face 68 and is adapted to be in register with each port 61 during subs-tantially the entire suction Vor intake stroke. The elongated portion of' the inlet port 62 at the beveled shoulder 68 is substantially semi-circular, extending around the seat 68 between substantially diametrically opposite points. lVith the inlet port 62 formed in this manner, a port 61 is in register or communication With the port 62 during approximately the entire intake stroke of a piston 12 and where there are four cylinders 13, the ports 61 come into register With the inlet port 62 successively so that there are tivo ports 61 in communication with the port 62 simultaneously.

1n accordance with the preferred form of the invention the discharge or outlet port 63 of the stationary element is formed so that a port 61 is in communication with the outlet port 63 during a portion of the compression stroke of a piston 12. When the mechanism is to handle gas, the

ports

61 and 63 are preferably formed and related so that a port 61 in communication with a given cylinder 13 is closed during the first part of the compression stroke of the piston 12, the corresponding cylinder, so that the fluid in the cylinder is compressed before the port 61 moves into register With the outlet port 63. The receiving end-of the outlet port 63 at the shoulder 68 is elongated and curved concentric to the' axis of rotation of the cylinder block 11. The distance between the port-

s

62 and 63 may be related to the size of the cylinders 13 so that a given pressure may be developed in the cylinders 13 before fluid is discharged into the outlet port 63. Then the mechanism is to handle a liquid, the

ports

61 and 62 are related so' that a given port 61 is in communication with the port 62 upon the start of the compression or out stroke of the piston in the "J cyli.ndei"connected with the port 61.

In the preferred form of the invention small sealing grooves 68a are formed in the seat 68 to extend around the seat above and balon7 or at opposite sides of the

ports

62 and 63. The grooves are effective in preventing 60 with the shoulder 68.

leakage of fluid between the valve ring and seat.

The projection 24 and-the portion providing the shoulder 68 may be integralwith the head 19. The head 19 is provided With a comparatively large space 73 for carrying a cooling medium to prevent overheating of the parts through engagement of the valve ring The space 73 may extend around the outer or peripheral portion of the end plate 19 and a central opening or space 71 may be provided in the head 19 for carrying a cooling medium. The invention provides means forvlubricating the bearing 25 and the valve ring 60. A conduit 72 eX-i tends through the head 19 from its outer end to deliver a lubricant to the end of the projection 24. The lubricant supplied through the conduit 72 effectively lubricates the bearing 25 and the valve ring 60.

It is believed that the operation of the compressor provided by the present invention will be readily apparent from the foregoing detailed description. Theshaft 15 may be rotated in any suitable manner to drive or rotate the cylinder block 11 and the drive ring 14. The drive ring 14 being tilted relative to the plane of rotation of the cylinder block 11.l 'causes the pistons 12 to reciprocate in the cylinders 13. The reciprocation of the pistons 12 in the cylinders causes fluid to be drawn through the port 62 and ports 61 into the cylinders 13 during the. intake strokes of the pistons. During the first part ofv the l.compression strokes of the pistons12 -the ports 61 are out of register with the outlet port so that they are closed bythe shoulder 68. Fluid is compressed in the cylinders 13 duringthe first part of the compression stroke, and when the ports 61 come into register With the outlet port 63 the compressed fluid is discharged through the port 63. It Will be apparent that the compressor is operable to effectively supply fluid under pressure to a line carrying considerablepressure.

It is to be noted that the invention provides a pump or compressor that is particula rly simple and compa-@tin construction and which operates with a minimum of noise. A suitable lubricant may be provided in the housing 10 so that the various parts ofthe mechanism in the housing are effectively lubricated during operation. The valve means 16 embodies but tevv simple parts. The head 19 provides the support for the cylinder block `1l as Well as the stationary element of the valve means 16. The head 19 is provided r`with the cooling medium containing spaces .73 and 72 so that the adjacent Working parts do not become overheated.

Having described only a typical preferred y form of my invention, I do not Wish to limit myself to the specific details set forth, but Wish to reserve to myself any changes or variations that may appear to those skilled in the stationary element having spaced ports, one

an inlet port, the other an outlet port, the cylinder block having ports communicating with the inner ends of the cylinders, and means for controlling the passage of fluid. through the ports of the cylinder block including, a valve ring connected with one element and retained in pressura] engagement with the other element to seal therewith and having "openings communicating with the i ports of said element with which it is gonnected land registering with 'one port of the said other element during the outward movement of the pistons and registerng with another port of the said other element during the inward movement of the pistons.

2. A mechanism of the character described including, a housing, two elements, one a stationary element carried by the housing, the other a rotatable cylinder block in the housing and rotatably mountcd'on the stationary element, pistons mounted for recprocation in the cylinders of the cylinder block, means for causing reciprocationof the pistons upon rotation of the cylinder block, the stationary ele-ment having spaced ports, one an inlet port, the other an outlet port, the cylinder block ha'ving ports commun-ieating` with the inner ends of the cylinders, and means for controlling the passage of fluid through the ports of the cylinder block including, a valve ring retained in pressural sealing engagement with the stationary element and connected with the cylinder block to rotate therewith, the valve ring having open'ngs communicating with the ports of the cylinder block and adapted to register with the inlet port during Ying and rotatably mounted on the stationary element, pistons mounted for recinrocation in the cylinders of the cylinder block. means for causing reciproca-tion of the pistonvs upon rotation of the cylinder block. the stationary element having spaced ports. one an inlet port,l the other an outlet port, the cylinder block having ports communicating with the inner ends ofthe cylinders and means for controlling the passage of iuid through the ports of the cylinder block including, a valve ring engaging the stationary element and slidably connected with the cylinder block to rotate therewith, and means holding the ring in engagement with the stationary element, the valve ring having openings-communicating with the ports of the cylinder block and adapted to register with the inlet port during the out strokes of the pistons, and adapted to register with the outlet port during the in strokes of the pistons.

4. A mechanism of the character described including, a housing, two elements', one a stationary element carried by the housing, the other a rotatable cylinder block in the housing and rotatably mounted on the stationary element, pistons mounted for reciprocation in the cylinders of the cylinder block means for causing reciprocation of the pistons upon rotation of the cylinder block, the stationary element having-spaced ports, one an4 inlet port, the other an outlet port, the cylinder block having ports communicating with the inner ends of the cylinders, and means for controlling the passage of fluid through the ports of the cylinder block including, a valve ring engaging the stationary element and connected with thecylinder block to rotate therei I with, and a spring holding the ring in engagement with the stationary element, the valve ring having openings communicating with the ports of the cylinderI block and adapted to register with the inlet port during the out strokes of the pistons, and adapted to register with the outlet port during the in strokes of the pistons.

5. A mechanism of the character described including, a housing, two elements,one a stationary element carried by the housing, the other a rotatable cylinder block in the housing and rotatably mounted on the stationary element, pistons mounted for reciprocation in the cylinder of the cylinder block, means for causing reciprocation ofthe pistons upon rotation of the cylinder block, the stationary element having spaced ports, one an inlet port, the other an outlet port, the cylinder block having ports communicating with the inner ends of the cylinders, and means for controlling the passage of fluid through the ports of the cylinder block including, a valve ring engaging the stationary element and connected with the cylinder block to rotate therewith, and means for maintaining the valve ring in pressural sealing engagement with the stationary element, the valve ring having openings communicating with the ports of the cylinder block and adapted to register with the inlet port during the out stroke of the pistons, and adapted to register with the outlet port during the last portions of the in stroke of the pistons;

6.- A mechanism of the characterdescribed includingLa housing, two elements, one a stagaging the stationary element and slidably` connected with the cylinder block to rotate therewith, theyalve ring having openings communicating with the ports of the cylinder block and adapted to register with the inlet port during the out stroke of the pistons, and adapted to registervwith the outlet port during the in stroke of .the pistons, the inlet port being elongated at the valve ring s o that the openings in the ring remain in` register with the inlet opening during substantially the entire out strokes of the pistons.

7. A mechanism of the character described including, a housing, two elements. one a stationary element carried bythe housing, the other a rotatable cylinder block in the housing and rotatably-mounted on the stationary element, pistons mounted for reciprocation in the cylinders of the cylinder block, means for causing reciprocation of the pistons upon rotation of the cylinder block, the stationary element having spaced ports, one an inlet port, the other an outlet port, the cylinder block having ports communicating with the inner ends of the cylinders. and means for.

controlling the passage of fluid through the ports of the cylinder block including, a valve ring engaging the stationary element and connected with the cylinder block to rotate therewith. and means for maintaining the valve ring in pressural sealing'engagement with the stationary element, the valve ring having openings communicating with the ports ot the' cylinder block and adapted to register with the inlet port during the out stroke of the pistons, and adapted to register" withv the outlet port during the in stroke of the pistons. the inlet port being elongated at the valve ring so that the openings in the ring remain in regi ster with the inlet opening during substantially the entirel out strokes of the pistons. the outlet port being spaced yfrom the inlet port at the ring so that the openings in the ring are closed during portions of the in strokes of the pistons.

8. A mechanism of the character described including` a housing. two elements, one a stationary element carried by the housing, the other a rotatable cylinder block in the housing and rotatably mounted on the stationary element. pistons mounted for reciprocation in the cylindersof the cylinder block, means for causing reciprocation of the pistons upon rotation of the cylinder block, the stationary element having spaced ports, one an inlet port, the other an outlet port, the cylinder block having ports communicating With the inner ends of the cylinders, and means for controlling the passage of fluid through 'the ports of the cylinder block including, a valve ring engaging the stationary element and connected with the cylinder block to rotate therewith, and spring means -for holding the valve ring in pressural sealing engagement with the stationary element, the valve ring having openings communicating with the ports of the cylinder block and adapted to register with the inlet port during the out stroke of the pistons, and adapted to register with the outlet port during the in stroke of the pistons, the inlet port being elongated at the valve ring and curved concentric to the axis of rotation of the mechanism so that the openings in the ring remain in register with the inlet port during aproximately the entire out strokes of the pistons, and the outlet port being elongated and concentrically curved and spaced from the inlet port so that the openings in the valve ring are closed after passing the inlet port during the first portions of the in strokes of the pistons before registering with the outlet port.

9. A mechanism of the character described including, a housing, two elements, one a stationary element carried by the housing, the other a rotatable cylinder block in the housing and rotatably mounted on the stationary element, pistons mounted for reciprocation in the cylinders of the cylinder block means for causing reciprocation of the pistons upon rotation of the cylinder block, the stationary element having spaced ports, one an inlet port, the other an outlet port` the cylinder block having ports communicatingwith the inner ends of the cylinders, and means for controlling the passage of fluid through the ports of the cylinder block including, a beveled seat on the stationary element, a valve ring slidably carried in an opening in the block and having a beveled end to cooperate with the seat, and means retaining the ring in cooperation with the` seat, there being openings -in the ring registering with the ports in the cylinder block, the inlet port being elongated at the seat to register with the openings in the ring during the out stroke of the pistons, and the outlet port being spaced from the inlet port at the seat to register with the said openings during a portion of the in stroke of each piston.

10.. A mechanism ofthe character described includin-g` a housing, two elements, one a stationary element carried by the housing, the other a rotatable cylinder block in the housing and rotatably mounted on the stationary element` pistons mounted for reciprocation in thecylinders of the cylinder block, means for causing reciprocaton of the pistons upon rotation of the cylinder block, the stationary element having spaced ports, one an inlet in cooperation with the seat. there being cylinders, and means for controlling the pasopenings in the ring registering with the ports in the cylinder block including a spring in the opening in the cylinder block, the inlet port being elongated at the seat -to register With the openings in the ring during thejont stroke of the pistons. and the outlet port being spaced from the inlet port `at the seat to register with the said openings during a portion of the in stroke of each piston.

11. A mechanism of the character described including, a housing, tivo elements, one a. stationary element carried bv the holising, the other a rotatable cylinder block in the housing and rotatably mounted on the stationary element, pistons mounted for reciprocat-ion in the cylinders of the cylinder block, means for causing reciprocation of the pistous upon .rotation of the cylinder block, the

stationary element having spaced ports, one an inlet port, the other an outlet port, the cylinder block having ports communicating With the inner ends of the sage of fluid through the ports of the cylinder block including, a beveled seat on the stationary element, a valve ring slidably carried in an opening in the block and-having a beveled end to cooperate with the seat, means for cooling the stationary element and the ring, and means retaining the ring in cooperation with the seat. there being openings in the ring registering With the ports in the cylinder block, the inlet port being elongated at the seat to register with the openings in the ring during the out stroke of the pistons, and the outlet port being spaced from the inlet port at the seat to register with the said lopenings during a portion of the in stroke of each piston. y

12. A mechanism of the character de- Y scribed including. a housing. two elements,

one a` stationary element carried by the housing, the other a rotatable cylinder block in the housing and rotatably mounted on the stationary element,v. pistons mounted for reciprocation in the cylinders of the cylinder block, means for causing reciprocation the pistons upon rotation of the cylinder block, the stationary element having spaced ports, one an inlet port, the otherza'n outlet port, the cylinder block having ports communicating with the inner ends of til@ cylinders, and

-being openings in the ring registering with the ports in the cylinder block, the inlet port being elongated at the seat to register with the openings` in the ring during the ont stroke of the pistons, and the outlet port being spaced from the inlet port at,` the seat to register With the said openings during a portion ot' the in stroke of each piston.

13. A mechanism of the character described including` a housing, two elements, one a stationary element carried by the housing, the other a rotatable cylinder block in the housing and rotatably mounted on the stationary element, pistons mounted for reciprocation in the cylinders of the cylinder block, means for causing reciprocation of the pistons upon rotation of the cylinder block, the stationary element vhaving spaced ports, one an inlet port, the other an outlet port, the cylinder block having ports communicating With the inner.. ends of the cylinders, and means 4for contlrolling the passage of fluid through the ports of the cylinder block including, a beveled seat on the stationary element, a valve ring slidably carried in an opening in the block and having a beveled end to cooperate With the seat, and means retaining the ring in cooperation with the seat, there being openings in the ring registering with the ports in the cylinder block, the inlet port being elongated at the seat to register With the openings in the ring during the out stroke of the pistons, and the outlet Ort being circumferentially spaced from tie inlet port at the seatl to register with the said openings during a portion of the in stroke of each piston.

14. A mechanism of the character described including, a housing, two elements,

- one a stationary element carried by the housone an inlet port, the other an outlet port, the

cylinder block having ports communicating with the inner ends of the cylinders, and means for controlling the passage of Huid through the ports of the cylinder block including, a beveled seat on the stationary ele-.

ment, a valve ring slidably carried in an opening in the block and having a beveled end to cooperate with the seat, and means retaining the ring in cooperation with theseat, there being openings in the ring `registering with the .ports in the cylinder block, the inlet port being elongated at the seat to register with the openings in the ring during the out stroke of the pistons, and the outlet port being circumferentially spaced from the inlet port at the seat to 'register With the said openings during a portion of the in stroke of each piston, there being a groove in the beveled seat for holding fluid to seal betweenthevstationary element and the ring.

15. A mechanism of the character described including, a housing, tWo elements,

one a stationary element carried by the housing, the other a rotatable cylinder block in the housing and rotatably mounted on the stationary element, pistons mounted for reciprothrough the ports of the cylinder block incation in the cylinders of the cylinder block, means for causing reciprocationi of the pistons uponrotation of the cylinder block, the stationary element having spaced ports, one an inlet port, the other an outlet port, the

cylinder block having ports communicating with the -inner ends 'of -the cylinders, and

means for controlling the passage of luid cluding, a beveled seat on thestationary element, a valve ring slidably carried in any opening in the block and having a beveled end to cooperatewith the seat, and means retaining the ring in cooperation with the seat, there being openings in the ring registering with the ports yin the cylinder block, the inlet port. being elongated at the seat to register .pistons upon rotation ofthe .cylinder block the stationary element having spaced ports,

with the openings inthe ring during the out stroke of the pistons, and the outlet port bei ing ciroumferentially spaced from the inlet port at uthe seatto register with the said openings during a portion of the in stroke of each piston, therebeing'a gr/ove in the ring to carry fluid to seal with the said seat.

16. A` mechanism of the character de n stationary element, pistons mounted for reciprocation in the-cylinders'of the cylinder block, means for causing reciprocation of the one an inlet port, the other an outlet port,

the cylinder block having ports communicating with the inner ends of the cylinders, and

means for controlling the passage of fluidthrough the ports ofthe cylinder block including, a beveled seat on the stationary element, a valve ring slidably carried in an ope-ning in the block andshaving a beveledV end to cooperate with the seat, and means retaining the ring 1n cooperation with the seat, there being openings inthe ring registering with the ports in the cylinder block, the inlet portl ton, there being grooves in the beveled seat and ring to hold fluidfor sealing with the seat and ring. l

. In Witness. that I claim the foregoing I have hereunto subscribed my name this 26th day of May, 1930.

CLARENCE S. SORENSEN.

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