US3690793A - Gear pump with lubricating means - Google Patents

Gear pump with lubricating means Download PDF

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Publication number
US3690793A
US3690793A US110179A US3690793DA US3690793A US 3690793 A US3690793 A US 3690793A US 110179 A US110179 A US 110179A US 3690793D A US3690793D A US 3690793DA US 3690793 A US3690793 A US 3690793A
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US
United States
Prior art keywords
housing
groove
zone
shaft
intermeshing teeth
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
US110179A
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English (en)
Inventor
Frederic W Pollman
Lee R Frandsen
Charles D Throckmorton Sr
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.)
Danfoss Power Solutions Inc
Original Assignee
Sundstrand Corp
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Publication date
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Publication of US3690793A publication Critical patent/US3690793A/en
Assigned to SUNDSTRAND-SAUER COMPANY, A GENERAL PARTNERSHIP OF DE reassignment SUNDSTRAND-SAUER COMPANY, A GENERAL PARTNERSHIP OF DE ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: SUNDSTRAND CORPORATION, A DE CORP.
Anticipated expiration legal-status Critical
Assigned to SAUER INC., reassignment SAUER INC., ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: SUNDSTRAND-SAUER COMPANY, A DE GENERAL PARTNERSHIP
Expired - Lifetime legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C15/00—Component parts, details or accessories of machines, pumps or pumping installations, not provided for in groups F04C2/00 - F04C14/00
    • F04C15/0003—Sealing arrangements in rotary-piston machines or pumps
    • F04C15/0023—Axial sealings for working fluid
    • F04C15/0026—Elements specially adapted for sealing of the lateral faces of intermeshing-engagement type machines or pumps, e.g. gear machines or pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2/00—Rotary-piston machines or pumps
    • F04C2/08—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F04C2/082—Details specially related to intermeshing engagement type machines or pumps
    • F04C2/088—Elements in the toothed wheels or the carter for relieving the pressure of fluid imprisoned in the zones of engagement

Definitions

  • ABSTRACT A high pressure rotary spur gear pump including a pair of gear members intermeshing at a location between an inlet and an outlet, a pair of shafts carrying the gear members and having opposite ends mounted in bearing sleeves, together with means for pumping lubricating fluid under pressure from an area at the zone of intermeshing teeth, where the spaces between teeth-are decreasing in volume, outwardly along the bearing sleeves at opposite ends of one shaft and back along the bearing sleeves at opposite ends of the other shaft, to the pump inlet.
  • the present invention relates to rotary spur gear pumps including a pair of pump rotors or gear members with intermeshing teeth, and in the preferred constructending from the gear members into bearing sleeves which mount the shafts for rotation. Because the gear shafts rotate with the gears, and the sleeve bearings are stationary, it is necessary to provide lubrication at the engaged surfaces of the shafts and the bearings.
  • shaft lubrication has been provided by static delivery of fluid to the bearing surfaces to be distributed by the adherence of lubricating fluid to the moving surface.
  • Such a system lacks positive direction of the fluid in predetermined quantity.
  • the present invention involves a lubrication system for a gear pump with parallel gear shafts wherein lubrication fluid is positively directed under pressure from a port under pressure at the zone of intermeshing teeth where the spaces between the teeth are decreasing in volume in a manner to force lubricating fluid in predetermined quantities to the bearing surfaces.
  • lubricating fluid is simultaneously directed outwardly along opposite ends of one shaft, laterally to the adjacent ends of the other shaft and back inwardly along the other shaft to the pump inlet chamber.
  • the lubricating fluid is pumped from the zone of intermeshing teeth at a location where spaces between the teeth are momentarily sealed by tooth contact from both the pump inlet chamber and the pump outlet chamber, trapping fluid under pressure, and forcing the trapped fluid in predetermined metered amounts to the bearing areas.
  • the specific passages for flow of lubricating fluid include a longitudinal groove along the inside of each bearing for distributing fluid to the interengaged bearing surfaces, an annular channel around each shaft at the inner end of the bearing groove, passages in the housing communicating outer ends of adjacent bearing grooves, a groove in each seal plate at opposite sides of the gears leading from the zone of intermeshing teeth to the annular channel on one shaft and a groove in each seal plate leading from the annular channels on the other shaft to' the inlet chamber.
  • FIG. 1 is a longitudinal sectional view through a pump embodying the present invention, taken at about the line 1--1 of FIG. 2;
  • FIG. 2 is a cross-sectional view taken at about the line 2-2 ofFIG. 1;
  • FIG. 3 is an elevational view of a pressure balance seal plate taken at about the line 33 of FIG. 1, viewing the pressure balance plate from the side in contact with the gears;
  • FIG. 4 is an elevational view of the pressure balance plate taken at about the line 4-4 of FIG. 1 viewing the opposite side of the plate;
  • FIG. 5 is a cross-sectional view taken at about the line 5-5 of FIG. 1, viewing the inner surface of the end housing member;
  • FIG. 6 is a sectional view through the housing member taken at about the line 6-6 of FIG. 5 showing the inlet and outlet ports in the housing member;
  • FIG. 7 is a fragmentary exploded view with a diagrammatic illustration of the path of flow of lubricating fluid
  • FIGS. 8-12 are enlarged fragmentary illustrations of the gear teeth at the zone of intermesh, with the teeth in various successive positions, demonstrating decreasing volumes in the spaces between teeth, resulting in positive displacement of lubricating fluid;
  • FIG. 13 is a diagrammatic illustration of the manner in which the lubricating fluid pickup groove in the face of the seal plate is located.
  • a pump construction embodying the present invention is illustrated as including a housing comprised of three outer members including an end housing member 10 suitably constructed for mounting the pump upon an appropriate support, an end housing member 11 formed with an inlet and an outlet, and a central housing member 12 in the form of a spacer plate.
  • the housing members 10, 11 and 12 are suitably aligned as by pins 14 at the top and bottom of FIGS. 1 and 2, and held in assembled relationship by machine bolts as at 16.
  • the housing members define an interior cavity for the pump gears, sealing means and inlet and outlet chambers.
  • Drive gear 18 is formed on a drive shaft 19, and idler gear or driven gear 20 is formed on a driven shaft 21.
  • the shafts 19 and 21 are arranged on parallel spaced axes in the housing with the teeth on the gear members meshing at a zone centrally located in the housing cavity.
  • Opposite ends of the shaft 21 project into bore recesses 24 and 25 in the housing members 11 and 10.
  • the bore 24 ends in the housing member 11 and the recess 25 in the housing member 10 is closed by an appropriate seal 26.
  • Opposite ends of the shaft 19 project into bore recesses 28 and 29 in the housing members 11 and 10.
  • each bearing sleeve 34 includes a longitudinal groove 35 preferably located as shown in FIG. 5 and referred to in more detail hereinafter.
  • an inlet chamber 37 is provided in the spacer plate 12 at one side of the zone of intermeshing gear teeth and an outlet chamber 38 is provided in the spacer plate 12 at the other side of the zone of intermeshing teeth. Both chambers extend outwardly from the spacer plate partially into the end housing members.
  • the inlet chamber 37 is always sealed from the outlet chamber 38 by means of tooth contact in the zone of intermeshing teeth and by sealing means engaging the outer edges of the gear teeth.
  • the inlet chamber is generally defined at one side of the intermeshing teeth and the outlet chamber is generally defined at the other side of the intermeshing teeth.
  • the outer tips of the gear teeth rotating from inlet to outlet are sealed by contact with inner surfaces of the spacer plate 12 as at 40 and 41 which define generally cylindrical gear cavities intersecting at the zone of intermeshing teeth.
  • the sides of the gear teeth are sealed by means of pressure balanced seal plates 43 and 44 generally of 8-shaped configuration fitted around the shafts and against opposite sides of the gears in cavities 40 and 41 in the spacer plate.
  • the inlet chamber 37 communicates with an axially disposed inlet passage 48 in the end housing member 11 having a laterally directed internally threaded terminus
  • outlet chamber 38 communicates with an axially disposed outlet passage 49 in the end housing member 11 having a laterally directed internally threaded terminus.
  • the threaded ends of passages 48 and 49 may be axially disposed.
  • the plate 43 is formed at each end on the periphery with a portion of reduced radius as at 50 to permit uniform distribution of the high pressure of outlet fluid along a predetermined portion of the gear side of the plate and behind the plate into an area 52 (FIG. 5) between a pair of sealing rings 54 and 55 in housing member 1 1, so that the area 52 is subjected to pressure corresponding generally to that in the outlet chamber.
  • the plate 43 is formed with ports 57 which admit fluid to the outside of theplate in areas within circular O-rings 58 in housing member 1 l at pressure intermediate the outlet pressure and the inlet pressure.
  • the gear side of the plate 44 is a mirror image of the gear side of the plate 43, and the outside of the plate 44 is subjected to fluid pressure similar to that supplied at the outside of plate 43.
  • lubricating fluid is pumped from trapped fluid in a sealed chamber at the zone of intermeshing teeth where the spaces between teeth decrease in volume, outwardly along the end portions of drive shaft 19, across to the end portions of driven shaft 21, and back inwardly along the latter to the inlet chamber.
  • each of the pressure balanced plates 43 and 44 is formed on the gear side adjacent the drive shaft 19 with a groove as at 60 (FIGS. 1, 3 and 7) which extends from the intermeshing teeth inwardly toward the shaft.
  • the groove 60 terminates at the inner end in communication with an annular channel as at 61 around the shaft defined radially by the inner surface of the pressure balance plate and the outer surface of the shaft, and defined axially by the inner end of the bearing sleeve and the outer surface of the gear.
  • the annular channel 61 communicates with the inner end of longitudinal groove 35 in the adjacent bearing sleeve 34 so that lubricating fluid may flow longitudinally outwardly along the drive shaft to the hearing recesses 28 and 29.
  • a groove 62 (FIG. 4) in the outer surface of each pressure plate around the drive shaft includes an O-ring 63 engaging the adjacent housing member.
  • the end housing member 11 is formed with a passage 64 which conducts lubricating fluid from the recess 28 to the recess 24.
  • End housing member 10 includes a passage 65 communicating the bearing recess 29 and the bearing recess 25 to permit lubricating fluid to flow to the latter.
  • Lubricating fluid in the recesses 24 and 25 flows inwardly along the driven shaft through the grooves 35 in bearing sleeves 34 to annular channels as at 68 surrounding the driven shaft at opposite sides of the idler gear, like those at 61 on the drive shaft.
  • Each annular channel 68 communicates with the pump inlet chamber 37 by means of a recess as at 69 in the face of the pressure plate adjacent the idler gear extending from annular channel 68 radially outwardly to the inlet chamber.
  • the lubricating circuit is illustrated diagrammatically by the broken line with arrows in the exploded view of FIG. 7.
  • the lubricating grooves 35 in bearings 34 are preferably located in the vicinity of the showing of FIG. 5 where the associated shaft is loaded least. That is to say, the shafts are usually forced inwardly toward each other by fluid pressure, and the lubricating grooves should be located outwardly from the place where the shafts are pressed hardest against the bearing sleeves.
  • FIGS. 812 illustrate the spaces between intermeshing teeth including teeth 70, 71 and 72 on drive gear 18 and teeth 73 and 74 on driven gear 20.
  • contact of tooth 71 with tooth 73 at 77 provides a seal against the inlet chamber 37.
  • Contact of tooth 72 with tooth 74 at 78 has just been made, providing a seal against the outlet chamber 38.
  • Fluid under pressure has been trapped in the space between gear teeth 71 and 74 including a chamber 80 adjacent gear 18, a chamber 81 adjacent gear 20 and a passage 82 connecting the chambers 80 and 81.
  • the lubrication pickup groove 60 is substantially covered by the gear 18 and the tooth 71.
  • the groove 60 is first uncovered slightly bythe tooth 71 as seen in FIG. 9.
  • the chamber 80 is decreasing in size, and fluid under pressure is forced from the chamber 80 into the lubrication groove 60.'In FIG. 10, the end of the lubrication groove 60 is totally uncovered and the chambers 80 and 81 are of substantially equal volume.
  • the volume of chamber 81 is increased, but to a lesser extent than the decrease in volume of chamber 80, as a result of which the net change in volume is a reduction which results in pumping lubrication fluid into the groove 60.
  • the chamber 81 increases in volume and the chamber 80 decreases in volume, so that there is a tendency for fluid to flow out of the chamber 80 and out of the groove 60 into the chamber 81.
  • the tooth 74 covers a substantial portion of the groove 60, and. the passage 82 becomes restricted.
  • chamber 81 reaches the edge 83 of the seal plate at the boundary of the inlet chamber, and by the time the teeth reach the position of FIG. 12, the contact at 77 is broken, and fluid flows into the chamber 81 from the inlet 37 so that all the fluid for the increasing volume of chamber 81 need not come from the chamber 80.
  • Chamber 81 is opened to inlet 37 promptly by location of the edge 83 of the seal plate close to the line connecting the gear centers while still maintaining adequate seal between inlet and outlet. Thus, only a small percentage of fluid, on the order of 5 percent, flows out of the slot 60 compared to that which was pumped into it.
  • the slot 60 In order to assure that the lubrication slot 60 provides positive flow of a predetermined metered amount of lubricating fluid to the bearings 34, the slot must be properly located.
  • the principles for locating the groove 60 are set forth in FIG. 13. As illustrated in FIG. 13, the uncovered end portion of groove 60 as seen in FIG. 10 should be located within the crosshatched area of FIG. 13.
  • the radically inner boundary of the crosshatched area lies on the root circle of the gear 18.
  • the radially outer boundary of the crosshatched area in FIG. 13 is defined by the line of action which connects the base circles of the two gears at the points of tangency.
  • the upper boundary of the crosshatched area in FIG. 13 (the leading edge in terms of gear rotation) is defined by a line connecting the centers of the two gears.
  • the-trailing edge in terms of gear rotation is a line drawn from the center of the drive gear to a place labeled POINT l which lies on the base circle and is located one tooth space from the point of tangency of the line of action to the base circle of the drive gear.
  • the end of the slot 60 need not conform identically with the shaded area in FIG. 13, but may be varied somewhat in order to facilitate machining which might not necessarily conform with the shaded area when performed in the most expeditious manner.
  • the pump operates at relatively high pressures, on the order of 3,000 to 3,500 psi, and in one embodiment has a capacity of 20 GPM. It is expected that lubricating fluidon the order of 0.5 percent (0.1 GPM) of the theoretical pump capacity will be pumped at about 5 psi into pickup grooves 60. Actually, the pressure in the trapped volume where lubricating flow originates might be greater than that in the outlet in the absence of relief and sometimes leads to chatter of movable parts. The pumping of lubricating fluid from the trapped volume therefore relieves pressure at that point and reduces noise. Adjacent the outlet, on the gear side of the seal plate, it is recessed as at to reduce the trapped volume between teeth near to gear 20 and shaft 21.
  • the pump embodies a lubricating system utilizing a predetermined quantity of fluid which is positively pumped from the sealed chamber between intermeshing teeth where fluid is trapped between the inlet chamber and the outlet chamber.
  • the system has the advantage that a predetermined quantity of lubricating fluid is pumped regardless of the pressures developed in the pump.
  • pressure lubricating systems where lubrication is dependent merely upon pressure drop rather than positive pumping, the amount of lubricating fluid flow varies with variations in pressure, and therefore the efficiency of the pump varies.
  • the lubricating flow bears a predetermined relationship to the over-all pump capacity and the volumetric efficiency as affected by lubrication flow remains substantially constant regardless of variations in pressure.
  • a high pressure rotary gear pump comprising,
  • said housing including seal plates at opposite sides of the gears and walls around the peripheries of the gears,
  • the intermeshing teeth forming a seal between the inlet and outlet and said housing including seal plates at opposite sides of the gears and walls around the peripheries of the gears,
  • a lubricating groove along each bearing means for pumping lubricating fluid under pressure from the zone of intermeshing teeth outwardly along one lubricating groove including i-l. a groove in one seal plate originating at the zone of intermeshing teeth where the space between intermeshing teeth is decreasing in volume and leading radially inwardly toward one shaft, and
  • said groove in the seal plate originating where a space between intermeshing teeth is sealed from the outlet chamber and sealed from the inlet chamber with fluid from the outlet,trapped therein,
  • a high pressure rotary gear pump comprising, a housing, a pair of external spur gears in the housing having gear teeth intermeshing at a zone centrally of the housing,
  • said housing including floating seal plates against opposite sides of the gears forming with the intermeshing teeth a seal between the inlet and outlet and walls sealing the gear teeth rotating from the inlet chamber to the outlet chamber,
  • i. means for pumping lubricating fluid from the zone of intermeshing teeth outwardly along the lubricating grooves at opposite ends of one shaft end and back through the adjacent bearing grooves at opposite ends of the other shaft to the inlet including,

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Rotary Pumps (AREA)
  • Details And Applications Of Rotary Liquid Pumps (AREA)
US110179A 1971-01-27 1971-01-27 Gear pump with lubricating means Expired - Lifetime US3690793A (en)

Applications Claiming Priority (1)

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US11017971A 1971-01-27 1971-01-27

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US110179A Expired - Lifetime US3690793A (en) 1971-01-27 1971-01-27 Gear pump with lubricating means

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US (1) US3690793A (de)
BE (1) BE778504A (de)
CA (1) CA966723A (de)
CH (1) CH539782A (de)
DE (1) DE2203820A1 (de)
FR (1) FR2124855A5 (de)
GB (1) GB1372482A (de)
IT (1) IT948331B (de)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2378960A1 (fr) * 1977-02-01 1978-08-25 Gen Signal Corp Pompe a engrenages perfectionnee a lubrification forcee de ses paliers
US4392798A (en) * 1981-04-03 1983-07-12 General Signal Corporation Gear pump or motor with low pressure bearing lubrication
US4927343A (en) * 1988-10-06 1990-05-22 Permco, Inc. Lubrication of gear pump trunnions
EP0455059A1 (de) * 1990-04-26 1991-11-06 FIATGEOTECH - TECNOLOGIE PER LA TERRA S.p.A. Zahnradpumpe
US5076770A (en) * 1990-04-13 1991-12-31 Allied-Signal Inc. Gear pump having improved low temperature operation
US5190450A (en) * 1992-03-06 1993-03-02 Eastman Kodak Company Gear pump for high viscosity materials
US5702234A (en) * 1995-12-01 1997-12-30 Micropump, Inc. Fluid pump with bearing set having lubrication path
US6135741A (en) * 1998-12-23 2000-10-24 Parker-Hannifin Corporation Recirculating flow path for gear pump
US20030194342A1 (en) * 2001-06-14 2003-10-16 Srinivas Bhagavatula Hydraulic pump utilizing floating shafts
US20060209627A1 (en) * 2003-08-07 2006-09-21 Mcgill Shane R Mixing apparatus
WO2010092447A3 (en) * 2009-02-16 2011-08-11 Fluid-O-Tech S.R.L. Wear resistant sliding plates for an external gear pump
US20160108914A1 (en) * 2014-10-16 2016-04-21 Johnson Electric S.A. Gear pump
CN109322821A (zh) * 2018-10-09 2019-02-12 宿迁学院 一种用于消除齿轮泵径向力的组合结构
CN114017313A (zh) * 2021-11-26 2022-02-08 宁波邦威泵业有限公司 一种凸轮式双转子泵

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4337018A (en) * 1980-01-29 1982-06-29 Commercial Shearing, Inc. Rotary impeller pump or motor with counterbalancing chamber in thrust plate bearing counterbore
DE4225804C2 (de) * 1992-08-05 1998-12-24 Bosch Gmbh Robert Zahnradmaschine

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2885965A (en) * 1955-03-21 1959-05-12 Borg Warner Pressure loaded pump lubricating means
US2993450A (en) * 1957-11-09 1961-07-25 Robert Bosch G M B H Fa Gear pump
US3145661A (en) * 1962-12-19 1964-08-25 New York Air Brake Co Pump
US3156191A (en) * 1960-12-23 1964-11-10 Clark Equipment Co Sealing means for pumps and motors
US3196800A (en) * 1962-12-13 1965-07-27 Parker Hannifin Corp Gear pump
US3490382A (en) * 1967-08-21 1970-01-20 Dowty Hydraulic Units Ltd Gearing and lubricating means therefor

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2885965A (en) * 1955-03-21 1959-05-12 Borg Warner Pressure loaded pump lubricating means
US2993450A (en) * 1957-11-09 1961-07-25 Robert Bosch G M B H Fa Gear pump
US3156191A (en) * 1960-12-23 1964-11-10 Clark Equipment Co Sealing means for pumps and motors
US3196800A (en) * 1962-12-13 1965-07-27 Parker Hannifin Corp Gear pump
US3145661A (en) * 1962-12-19 1964-08-25 New York Air Brake Co Pump
US3490382A (en) * 1967-08-21 1970-01-20 Dowty Hydraulic Units Ltd Gearing and lubricating means therefor

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2378960A1 (fr) * 1977-02-01 1978-08-25 Gen Signal Corp Pompe a engrenages perfectionnee a lubrification forcee de ses paliers
US4160630A (en) * 1977-02-01 1979-07-10 General Signal Corporation Gear pumps with low pressure shaft lubrication
US4392798A (en) * 1981-04-03 1983-07-12 General Signal Corporation Gear pump or motor with low pressure bearing lubrication
US4927343A (en) * 1988-10-06 1990-05-22 Permco, Inc. Lubrication of gear pump trunnions
EP0411225A1 (de) * 1989-08-03 1991-02-06 Permco, Inc Drehzapfenschmierung für eine Zahnradpumpe
US5076770A (en) * 1990-04-13 1991-12-31 Allied-Signal Inc. Gear pump having improved low temperature operation
EP0455059A1 (de) * 1990-04-26 1991-11-06 FIATGEOTECH - TECNOLOGIE PER LA TERRA S.p.A. Zahnradpumpe
US5190450A (en) * 1992-03-06 1993-03-02 Eastman Kodak Company Gear pump for high viscosity materials
EP0559582A1 (de) * 1992-03-06 1993-09-08 Eastman Kodak Company Zahnradpumpe für hochviskose Medien
US5702234A (en) * 1995-12-01 1997-12-30 Micropump, Inc. Fluid pump with bearing set having lubrication path
US6135741A (en) * 1998-12-23 2000-10-24 Parker-Hannifin Corporation Recirculating flow path for gear pump
US6692244B2 (en) * 2001-06-14 2004-02-17 Monarch Hydraulics, Inc. Hydraulic pump utilizing floating shafts
US20030194342A1 (en) * 2001-06-14 2003-10-16 Srinivas Bhagavatula Hydraulic pump utilizing floating shafts
US6716011B2 (en) 2001-06-14 2004-04-06 Monarch Hydraulics, Inc. Hydraulic pump utilizing floating shafts
US8142068B2 (en) 2003-08-07 2012-03-27 Mcgill Technology Limited Mixing apparatus
US7938574B2 (en) * 2003-08-07 2011-05-10 Mcgill Technology Limited Mixing apparatus
US20110205834A1 (en) * 2003-08-07 2011-08-25 Mcgill Technology Limited Mixing Apparatus
US20060209627A1 (en) * 2003-08-07 2006-09-21 Mcgill Shane R Mixing apparatus
WO2010092447A3 (en) * 2009-02-16 2011-08-11 Fluid-O-Tech S.R.L. Wear resistant sliding plates for an external gear pump
US20160108914A1 (en) * 2014-10-16 2016-04-21 Johnson Electric S.A. Gear pump
CN105526160A (zh) * 2014-10-16 2016-04-27 德昌电机(深圳)有限公司 齿轮泵
US10415566B2 (en) * 2014-10-16 2019-09-17 Johnson Electric International AG Gear pump
US10612545B2 (en) 2014-10-16 2020-04-07 Johnson Electric International AG Gear pump
CN109322821A (zh) * 2018-10-09 2019-02-12 宿迁学院 一种用于消除齿轮泵径向力的组合结构
CN114017313A (zh) * 2021-11-26 2022-02-08 宁波邦威泵业有限公司 一种凸轮式双转子泵
CN114017313B (zh) * 2021-11-26 2023-08-22 宁波邦威泵业有限公司 一种凸轮式双转子泵

Also Published As

Publication number Publication date
CA966723A (en) 1975-04-29
FR2124855A5 (de) 1972-09-22
BE778504A (fr) 1972-05-16
CH539782A (de) 1973-07-31
DE2203820A1 (de) 1972-09-07
IT948331B (it) 1973-05-30
GB1372482A (en) 1974-10-30

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AS Assignment

Owner name: SUNDSTRAND-SAUER COMPANY, A GENERAL PARTNERSHIP OF

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:SUNDSTRAND CORPORATION, A DE CORP.;REEL/FRAME:005261/0112

Effective date: 19890807

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Owner name: SAUER INC.,

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:SUNDSTRAND-SAUER COMPANY, A DE GENERAL PARTNERSHIP;REEL/FRAME:005919/0145

Effective date: 19900129