US2117652A - Pump and compressor - Google Patents

Pump and compressor Download PDF

Info

Publication number
US2117652A
US2117652A US131244A US13124437A US2117652A US 2117652 A US2117652 A US 2117652A US 131244 A US131244 A US 131244A US 13124437 A US13124437 A US 13124437A US 2117652 A US2117652 A US 2117652A
Authority
US
United States
Prior art keywords
blocks
casing
pump
head
compressor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US131244A
Inventor
Chamier John Adrian
Jones George Frederick
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US131244A priority Critical patent/US2117652A/en
Application granted granted Critical
Publication of US2117652A publication Critical patent/US2117652A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/12Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F04B1/20Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
    • F04B1/22Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block having two or more sets of cylinders or pistons
    • F04B1/24Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block having two or more sets of cylinders or pistons inclined to the main shaft axis

Definitions

  • This invention has reference to pumps and compressors comprising two cylinder blocks rotatably mounted at an angle to each other with an end of each block adjacent to an end of the other and with angular pistons arranged one end of each piston in a cylinder in one block and the other end in a cylinder in the other block.
  • Such pumps and compressors are desirable because they give substantially continuous output in spite of using reciprocating pistons and one object of the present invention is to provide an improved construction of a pump or compressor according to the above wherein the driving force is directly applied to both blocks as distinct from being applied to one block and transmitted to the other through bevel gearing or through the pistons.
  • a further object of the invention is to provide in the pump or compressor an improved construction of worm gear wherein the thrust of a worm on the worm wheels for effecting the direct driving of the rotary blocks has no longitudinal turning moment about the bearings supporting the wheels.
  • Another object of the invention is the provision of an improved construction of pump or compressor as set forth above wherein bearings for the rotary blocks, valve plates and head blocks are secured to a casing by easily accessible bolts common to these elements.
  • a still further object of the invention is the provision in the pump or compressor of valve plates which, in addition to their function as such, act as spacers or shims ensuring an exactly correct tolerance between themselves and the head end of the rotary blocks in contact with them.
  • an object of the invention is to provide an improved mounting for the rotary blocks whereby the valve plates at the head ends prevent outward displacement of the blocks with respect to the pump or compressor casing whilst appropriately fashioned surfaces at the other or adjacent ends of the blocks prevent inward movement of the said blocks.
  • Fig. 1 is a side elevation, mainly in vertical section, of the preferred form of pump or compressor according to the invention
  • Fig. 2 is a sectional elevation on the line II-IL Fig. 1;
  • Fig. 3 is an end elevation applicable to either head block illustrated in Fig. 1;
  • Fig. 4 is an end view, looking from the rotary block end, applicable to either valve plate;
  • Fig. 5 is a sectional elevation of the rotary block on the line 'v1-JT, Fig. l.
  • valve plates 5 and head blocks 6 are located at the ends of the said casing, one plate and head being in alignment with one rotary block and the other plate and head in alignment with the remaining rotary block.
  • the casing consists of an upper part 'l and a tray or lower part il secured to the upper part by bolts and nuts 9 passing through flanges l0 on the parts 'F and 8.
  • the casing has constricted ends Il, H each co-aXially containing one of the rotary blocks.
  • Annular recesses I2 are provided at the inner ends of the constrictions for the reception of anges I3 on bearing sleeves I4.
  • the sleeves i@ are held in place by means of bolts I5 which pass through tubular ribs I6 on the head blocks through lugs Il on the valve plates 5 and lugs It at the outer ends of the constrictions Il, and screw into the anges l2 after passing through holes in the bridges I9 joining the constrictions Il to the casing. It will thus be seen that bolts i5 provide common securing means for each set of elements I4, 5 and 6.
  • 'I'he worm wheels 2i are integral with and circumscribe their respective blocks and the parts as 2l of the blocks that make bearing Contact with the sleeves i4.
  • the circumscribing is effected by arranging the worm wheels at the larger ends of cones 22 extending towards the planes containing the head ends of the rotary blocks.
  • the worm wheels and, therefore, the pump or compressor are driven by means of a worm 23 arranged in the corner between the wheels 2i] at right angles to the central plane of the engine.
  • Bearing bushes 2t mounted in sockets 25 formed in the casing support the shaft 26 of the worm.
  • One end 2i of the shaft projects well beyond the casing and is splined for co-operation with a coupling element rotated by the driving means for the pump or compressor; and between this end and the worm is arranged a thrust disc 28.
  • This disc runs between a flange 29 on the upper end of one of the bushes 24, said bush and ange being of white or bearing metal, and a dished bearing plate 3u of like metal.
  • outer or head ends of the rotary blocks have ports 36 to enable fluid to flow into and out of the cylinder bores 3.
  • ports 36 register rst with one opening 3l in a valve plate and then with the other opening.
  • the valve plates bear against the outer or head ends of their respective rotary blocks and each has an annular flange 38 which surrounds the unreduced end 39 of a block to provide a second bearing therefor.
  • the ilanges 33 t closely in their constrictions Il so as to receive stability from the casing.
  • the valve plates 5 prevent outward movement of the blocks with respect to the casing and the conical surfaces of the cones 22 are in rolling contact at the corner of the angle so that the rotary blocks cannot move inwardly.
  • the exact degree of tolerance is determined b-y the thickness of the plates 5 between the lugs i8 on the casing and the lugs i3 on the head: the more this thickness is reduced from the sides in contact with the lugs I8 the more the middle parts of the plates project into the constrictions H and the closer these parts come to the outer ends of the rotary blocks.
  • Each head block is substantially in the form of a hollow cylinder closed at its outer end 40 and divided intotwo symmetrical compartments M by a vertical partition 42.
  • the partition has a central circular flange 53 which, in addition to holding the plate 5 upto the outer end of its rotary block, provides two arcuate openings 44 in register with the openings 3l in a valve plate 5.
  • Rectilinear protuberances 5 at one side of each head block are provided with two holes 46 communieating one with one compartment 4I and one with the other compartment whilst both are screw-threaded for the reception of unions connecting supply and outflow pipes to the head.
  • the worm 23 When the worm 23 is rotated it turns the blocks 2i in synchronism and the pistons 2 are carried round by the blocks with the result that they reciprocate.
  • One compartment 4I in one head block S and the corresponding compartment in the other head block receive fluid from the supply pipe and allow it to pass through corresponding openings 44 and 3l and Ithrough ports 36 into bores 3, the fluid so flowing owing to the suction created by those pistons moving away from the head ends of the blocks.
  • the said pistons When the said pistons move towards the head ends they discharge the iiuid through ports 36, through the other openings 31 and the openings Gli into the remaining compartments 4l, said fluid passing from thence through outflow pipes. If the worm 23 is driven in the opposite direction the fluid flow is reversed.
  • a drive directly applied to said cylinder blocks comprising two worm wheels around the said blocks near the said adjacent ends and having a rolling contact in the acute angle formed by the blocks and a single driving worm in mesh with both worm wheels in line with the rolling contact between the said wheels.
  • rotary cylinder blocks are each provided with a conical end, with the said ends in rolling contact with each other, and wherein the said worm wheels are rigid with said conical end and circumscribe the cylinder blocks, with bearing elements around said blocks adjacent the conical ends thereof, and bearing elements around the cylinder blocks at the ends remote from the conical ends.
  • a pump or compressor as deiined in claim l wherein the said rotary cylinder blocks are each provided with a, conical end, with the said ends making rolling contact with each other, the conical end of each block inclining outwardly from the inner terminal of the block, the said worm Wheels being rigid with the conical ends of the cylinder blocks substantially in the plane of the maximum diameter of said conical ends, together with bearing elements around the cylinder blocks between said blocks and said worm wheels, and bearing elements for the cylinder blocks at the ends of said blocks remote from the conical ends.
  • a casing containing said cylinder blocks and said pistons, a bearing sleeve at the inner face of one side o-l' said casingand a bearing sleeve at the inner face of a side at right angles thereto, said sleeves surrounding the cylinder blocks near the said adjacent ends thereof, a valve plate at the outer face of each side, head blocks on the outer faces of said valve plates, and bolts passing through said head blocks, said valve plates and said sides of the casing and screwing into said bearing sleeves to secure the sleeves, valve plates and head blocks in position on the casing.
  • a casing containing said cylinder blocks and said pistons, a constriction at one side of said casing and a constriction at the side at right angles thereto, a bearing sleeve at the inner end of each constriction, said sleeves surrounding the cylinder blocks near the said adjacent ends thereof, a valve plate at the outer end of each constriction, head blocks on the outer faces of said valve plates, and bolts passing through said head blocks and through said valve plates, extending along said constrictions and screwing into said bearing sleeves to secure the sleeves, valve plates and head blocks in position on the casing.
  • a casing containing said cylinder blocks and said pistons, a constriction at one side of said casing and a constriction at the side at right angles thereto, a bearing sleeve at the inner end of each constriction, said sleeves surrounding the cylinder blocks near the said adjacent ends thereof, valve plates at the outer ends of the constrictions, an annular flange on each valve plate closely ttng into each constriction, the outer ends of said cylinder blocks entering said anges to be borne thereby, ⁇ head blocks on the outer faces of said valve plates, and bolts passing through said head blocks and through said valve plates, extending along said constrictions and screwing into said bearing sleeves to secure the sleeves, valve plates and head blocks in position on the casing.
  • a casing In a pump or compressor according to claim l, a casing, said blocks being mounted atright angles to each other in said casing with their outer ends adjacent to the sides of the casing, a valve plate at these sides and means for clamping said valve plates in position at peripheral portions thereof whereby clearance between said valve plates and the ends of saidblocks can be exactly set by alterations in the effective thickness of said peripheral portions of the valve plates.

Description

May 17, 1938. J. A. CHAMIERET AL 2,117,652
PUMP AND COMPRESSOR Filed March 16, 1957 2 sheets-sheet 1 v/C/E'.
.rfa/fn lEham/ef @sorge E' afanes May 17, 1938 J. A. CHAMIR ET AL PUMP AND- COMPRESSOR 2 Sheets-Sheet 2 Filed March 16, 1937 5 ITE L /w 5U 5 2 Pi f/ y, 4. f\ \4 1V, 6 HW 0,5 mw wr, U5@ mi H w 5 2// H 4 n 4 m 2 1 w H ..0 FJ f 07AM 5 I. 5 9 3 5 M f y w M w M I Z Patented May 17, 1938 UNITED STATES PATENT FFICE PUMP AND COMPRESSOR London, England Application. March 16,
9 Claims.
This invention has reference to pumps and compressors comprising two cylinder blocks rotatably mounted at an angle to each other with an end of each block adjacent to an end of the other and with angular pistons arranged one end of each piston in a cylinder in one block and the other end in a cylinder in the other block.
Such pumps and compressors are desirable because they give substantially continuous output in spite of using reciprocating pistons and one object of the present invention is to provide an improved construction of a pump or compressor according to the above wherein the driving force is directly applied to both blocks as distinct from being applied to one block and transmitted to the other through bevel gearing or through the pistons.
A further object of the invention is to provide in the pump or compressor an improved construction of worm gear wherein the thrust of a worm on the worm wheels for effecting the direct driving of the rotary blocks has no longitudinal turning moment about the bearings supporting the wheels.
Another object of the invention is the provision of an improved construction of pump or compressor as set forth above wherein bearings for the rotary blocks, valve plates and head blocks are secured to a casing by easily accessible bolts common to these elements.
A still further object of the invention is the provision in the pump or compressor of valve plates which, in addition to their function as such, act as spacers or shims ensuring an exactly correct tolerance between themselves and the head end of the rotary blocks in contact with them.
Further, an object of the invention is to provide an improved mounting for the rotary blocks whereby the valve plates at the head ends prevent outward displacement of the blocks with respect to the pump or compressor casing whilst appropriately fashioned surfaces at the other or adjacent ends of the blocks prevent inward movement of the said blocks.
The above and other objects of the invention will be clear from the accompanying drawings taken in conjunction with the following description.
In the said drawings:
Fig. 1 is a side elevation, mainly in vertical section, of the preferred form of pump or compressor according to the invention;
Fig. 2 is a sectional elevation on the line II-IL Fig. 1;
1937, Serial No. 131,244
(Cl. 10S-162) Fig. 3 is an end elevation applicable to either head block illustrated in Fig. 1;
Fig. 4 is an end view, looking from the rotary block end, applicable to either valve plate; and
Fig. 5 is a sectional elevation of the rotary block on the line 'v1-JT, Fig. l.
In the drawings two rotary cylinder blocks l at right angles to each other and containing the ends of four right angled pistons 2 in their equiangularly spaced= longitudinal bores 3 are arranged within a casing 4; and valve plates 5 and head blocks 6 are located at the ends of the said casing, one plate and head being in alignment with one rotary block and the other plate and head in alignment with the remaining rotary block.
The casing consists of an upper part 'l and a tray or lower part il secured to the upper part by bolts and nuts 9 passing through flanges l0 on the parts 'F and 8. The casing has constricted ends Il, H each co-aXially containing one of the rotary blocks. Annular recesses I2 are provided at the inner ends of the constrictions for the reception of anges I3 on bearing sleeves I4.
The sleeves i@ are held in place by means of bolts I5 which pass through tubular ribs I6 on the head blocks through lugs Il on the valve plates 5 and lugs It at the outer ends of the constrictions Il, and screw into the anges l2 after passing through holes in the bridges I9 joining the constrictions Il to the casing. It will thus be seen that bolts i5 provide common securing means for each set of elements I4, 5 and 6.
'I'he worm wheels 2i) are integral with and circumscribe their respective blocks and the parts as 2l of the blocks that make bearing Contact with the sleeves i4. The circumscribing is effected by arranging the worm wheels at the larger ends of cones 22 extending towards the planes containing the head ends of the rotary blocks.
The worm wheels and, therefore, the pump or compressor are driven by means of a worm 23 arranged in the corner between the wheels 2i] at right angles to the central plane of the engine. Bearing bushes 2t mounted in sockets 25 formed in the casing support the shaft 26 of the worm. One end 2i of the shaft projects well beyond the casing and is splined for co-operation with a coupling element rotated by the driving means for the pump or compressor; and between this end and the worm is arranged a thrust disc 28. This disc runs between a flange 29 on the upper end of one of the bushes 24, said bush and ange being of white or bearing metal, and a dished bearing plate 3u of like metal. A plate 3l clamped to the casing l by means of bolts and nuts 32 holds the plate 33 in place. Thrust of the worm 23 in an outward direction along its shaft 26 is taken by the plate 30 and pull or thrust in the opposite direction is taken by the flange 29, said ange 28 thrusting against part of the casing 4. A recess 33 co-axially of a centric boss 34 through which the outer end of the shaft 2B passes receives a packing box 35 that prevents escape of lubricant from the interior of the casing d.
'Ihe outer or head ends of the rotary blocks have ports 36 to enable fluid to flow into and out of the cylinder bores 3. During the working of the pump or compressor ports 36 register rst with one opening 3l in a valve plate and then with the other opening. The valve plates bear against the outer or head ends of their respective rotary blocks and each has an annular flange 38 which surrounds the unreduced end 39 of a block to provide a second bearing therefor. The ilanges 33 t closely in their constrictions Il so as to receive stability from the casing.
Owing to the worm wheels 2|) circumscribing the rotary blocks in planes between the end bearing surfaces at 2l and lthe Worm wheel 23 does not tend to tilt the blocks on their longitudinal axes i. e., the thrust of the worm wheel has no turning moment about the bearings along the longitudinal axes of the rotary blocks.
The valve plates 5 prevent outward movement of the blocks with respect to the casing and the conical surfaces of the cones 22 are in rolling contact at the corner of the angle so that the rotary blocks cannot move inwardly. The exact degree of tolerance is determined b-y the thickness of the plates 5 between the lugs i8 on the casing and the lugs i3 on the head: the more this thickness is reduced from the sides in contact with the lugs I8 the more the middle parts of the plates project into the constrictions H and the closer these parts come to the outer ends of the rotary blocks.
Each head block is substantially in the form of a hollow cylinder closed at its outer end 40 and divided intotwo symmetrical compartments M by a vertical partition 42. The partition has a central circular flange 53 which, in addition to holding the plate 5 upto the outer end of its rotary block, provides two arcuate openings 44 in register with the openings 3l in a valve plate 5. Rectilinear protuberances 5 at one side of each head block are provided with two holes 46 communieating one with one compartment 4I and one with the other compartment whilst both are screw-threaded for the reception of unions connecting supply and outflow pipes to the head.
When the worm 23 is rotated it turns the blocks 2i in synchronism and the pistons 2 are carried round by the blocks with the result that they reciprocate. One compartment 4I in one head block S and the corresponding compartment in the other head block receive fluid from the supply pipe and allow it to pass through corresponding openings 44 and 3l and Ithrough ports 36 into bores 3, the fluid so flowing owing to the suction created by those pistons moving away from the head ends of the blocks. When the said pistons move towards the head ends they discharge the iiuid through ports 36, through the other openings 31 and the openings Gli into the remaining compartments 4l, said fluid passing from thence through outflow pipes. If the worm 23 is driven in the opposite direction the fluid flow is reversed.
What we claim is:-
1. In a pump or compressor comprising two cylinder blocks rotatably mounted at an angle to each other with an end of each block adjacent to an end of the other and with 'angular pistons arranged one end of each piston in a cylinder in one block and the other end in a cylinder in the other block, a drive directly applied to said cylinder blocks comprising two worm wheels around the said blocks near the said adjacent ends and having a rolling contact in the acute angle formed by the blocks and a single driving worm in mesh with both worm wheels in line with the rolling contact between the said wheels.
2. In a pump or compressor according to claim 1, bearing elements around the blocks near the said adjacent ends, bearing elements around the opposite ends of the said blocks, the said worm wheels circumscribing the said blocks, the centre planes of said wheels lying between said bearing elements whereby the thrust of said worm on said blocks has no longitudinal turning moment about the said bearings.
3. In a pump or compressor as defined in claim l., wherein the rotary cylinder blocks are each provided with a conical end, with the said ends in rolling contact with each other, and wherein the said worm wheels are rigid with said conical end and circumscribe the cylinder blocks, with bearing elements around said blocks adjacent the conical ends thereof, and bearing elements around the cylinder blocks at the ends remote from the conical ends.
4. A pump or compressor as deiined in claim l, wherein the said rotary cylinder blocks are each provided with a, conical end, with the said ends making rolling contact with each other, the conical end of each block inclining outwardly from the inner terminal of the block, the said worm Wheels being rigid with the conical ends of the cylinder blocks substantially in the plane of the maximum diameter of said conical ends, together with bearing elements around the cylinder blocks between said blocks and said worm wheels, and bearing elements for the cylinder blocks at the ends of said blocks remote from the conical ends.
5. In a pump or compressor according to claim 1, a casing containing said cylinder blocks and said pistons, a bearing sleeve at the inner face of one side o-l' said casingand a bearing sleeve at the inner face of a side at right angles thereto, said sleeves surrounding the cylinder blocks near the said adjacent ends thereof, a valve plate at the outer face of each side, head blocks on the outer faces of said valve plates, and bolts passing through said head blocks, said valve plates and said sides of the casing and screwing into said bearing sleeves to secure the sleeves, valve plates and head blocks in position on the casing.
6. In a pump or compressor according to claim 1, a casing containing said cylinder blocks and said pistons, a constriction at one side of said casing and a constriction at the side at right angles thereto, a bearing sleeve at the inner end of each constriction, said sleeves surrounding the cylinder blocks near the said adjacent ends thereof, a valve plate at the outer end of each constriction, head blocks on the outer faces of said valve plates, and bolts passing through said head blocks and through said valve plates, extending along said constrictions and screwing into said bearing sleeves to secure the sleeves, valve plates and head blocks in position on the casing.
7. In a pump or compressor according to claim 1, a casing containing said cylinder blocks and said pistons, a constriction at one side of said casing and a constriction at the side at right angles thereto, a bearing sleeve at the inner end of each constriction, said sleeves surrounding the cylinder blocks near the said adjacent ends thereof, valve plates at the outer ends of the constrictions, an annular flange on each valve plate closely ttng into each constriction, the outer ends of said cylinder blocks entering said anges to be borne thereby,` head blocks on the outer faces of said valve plates, and bolts passing through said head blocks and through said valve plates, extending along said constrictions and screwing into said bearing sleeves to secure the sleeves, valve plates and head blocks in position on the casing.
8. In a pump or compressor according to claim l, a casing, said blocks being mounted atright angles to each other in said casing with their outer ends adjacent to the sides of the casing, a valve plate at these sides and means for clamping said valve plates in position at peripheral portions thereof whereby clearance between said valve plates and the ends of saidblocks can be exactly set by alterations in the effective thickness of said peripheral portions of the valve plates. 9. In a pump or compressor according to claim l, a casing of right angled form, bearing sockets in the angle of said casing at right angles to the central plane of the pump or compressor, bearing bushes in said sockets, and a shaft borne by said bushes, the said Worm cooperating With the said Worm Wheels being carried on said shaft.
JOHN ADRIAN CHAMIER.
GEORGE FREDERICK JONES.
US131244A 1937-03-16 1937-03-16 Pump and compressor Expired - Lifetime US2117652A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US131244A US2117652A (en) 1937-03-16 1937-03-16 Pump and compressor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US131244A US2117652A (en) 1937-03-16 1937-03-16 Pump and compressor

Publications (1)

Publication Number Publication Date
US2117652A true US2117652A (en) 1938-05-17

Family

ID=22448581

Family Applications (1)

Application Number Title Priority Date Filing Date
US131244A Expired - Lifetime US2117652A (en) 1937-03-16 1937-03-16 Pump and compressor

Country Status (1)

Country Link
US (1) US2117652A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4277049A (en) * 1980-05-19 1981-07-07 Clausen Donald A Lift structure for servicing vehicles
US5304043A (en) * 1992-09-29 1994-04-19 Avmed Compressor Corporation Multiple axis rotary compressor

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4277049A (en) * 1980-05-19 1981-07-07 Clausen Donald A Lift structure for servicing vehicles
US5304043A (en) * 1992-09-29 1994-04-19 Avmed Compressor Corporation Multiple axis rotary compressor
US5415530A (en) * 1992-10-28 1995-05-16 Avmed Compressor Corporation Axial piston gas compressor

Similar Documents

Publication Publication Date Title
US7536857B1 (en) Zero turn drive apparatus
US5540563A (en) Unitary housing for double hydraulic unit
US3291068A (en) Hydraulic axial-piston machine
OA11401A (en) Pressure exchanger.
US20110268598A1 (en) Gear pump
US1770683A (en) Pump
US3818808A (en) Dual cylinder operator for imparting rotary motion
US3528317A (en) Internal combustion engine
EP0667454B1 (en) Gear pump
US2771037A (en) Twin cylinder spray pump
US2117652A (en) Pump and compressor
US2691350A (en) Hydraulic equipment
US6607462B2 (en) Hydrostatic transaxles
US2346761A (en) Hydraulic gear pump
US2968286A (en) Hydraulic axial-piston machine
US2569734A (en) Valve and pump
US3033124A (en) Mud pumps
US4454802A (en) Piston assembly for a fluid mechanism with reaction plate, complete with slipper block
US2426588A (en) Pump or motor
US1942064A (en) Rotary pump
US2023609A (en) Pump and motor structure
GB1118434A (en) Hydraulic apparatus
AU601217B2 (en) Pump
US3152551A (en) Pump
US2756962A (en) Hydraulic power apparatus