EP0819218B1 - Positive displacement hydraulic machines - Google Patents
Positive displacement hydraulic machines Download PDFInfo
- Publication number
- EP0819218B1 EP0819218B1 EP96908244A EP96908244A EP0819218B1 EP 0819218 B1 EP0819218 B1 EP 0819218B1 EP 96908244 A EP96908244 A EP 96908244A EP 96908244 A EP96908244 A EP 96908244A EP 0819218 B1 EP0819218 B1 EP 0819218B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- casing
- spigot
- bores
- overlapping
- cover
- 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
Links
Images
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
- 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
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- 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
- F04C2/086—Carter
-
- 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
- F04C2/12—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type
- F04C2/14—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons
Definitions
- This invention relates to positive displacement hydraulic machines of the kind comprising a gear pump or motor having a body in which there are formed overlapping bores within which two gears are disposed for rotation in mesh with each other.
- the body is adapted to accommodate the gears with minimal radial clearance at the tips of their teeth and minimal axial clearance at their end faces.
- the body comprises a casing with two end covers in which there are mounted bearings for supporting two parallel shafts carrying respective gears, at least one of the covers being separate from the casing to enable the machine to be assembled and being secured to the casing as by set-screws.
- One end of one of the shafts projects from the body and constitutes the power input in the case of a pump and the power output in the case of a motor.
- the invention comprises a positive displacement hydraulic machine comprising a casing in which there are formed overlapping bores adapted to receive two gears for rotation in mesh with each other and one or more end covers adapted to be located on the casing characterised in that the one or more end covers are adapted to be located on the casing by means of an integral non-circular spigot which fits directly into the adjacent ends of the overlapping bores.
- the spigot has an end profile which comprises portions of two overlapping circles smoothly interconnected by arcs to form a waisted shape approximating to a figure of eight.
- the spigot may be a close clearance fit in the adjacent ends of the overlapping bores, preferably it is an interference fit therein.
- radius means are provided between the inner end face of the cover and the spigot formed thereon, and chamfer means for accommodating the radius means and facilitating press-fitting of the cover into the casing are provided at the adjacent ends of the overlapping bores.
- a gear pump body comprises a casing 10 with an integral end cover 12 and a separate end cover 14.
- overlapping parallel bores 16 formed in the casing 10 with their centre-lines in a plane 18 are intersected by parallel troughs 20 and 22 formed symmetrically about a plane 24 perpendicular to the plane 18, the trough 20 being deeper than the trough 22.
- An inlet port 26 having its centre-line in the plane 24 communicates with the trough 20, and an outlet port 28 likewise having its centre-line in that plane communicates with the trough 22.
- the casing 10 has a flat end face 30 in which there are formed four tapped holes 32 and an asymmetrical groove 34.
- Parallel blind bores 36 which are not quite co-axial with the overlapping bores 16 are formed in the casing 10 for the purpose of accommodating bearings for one end of the shafts carrying the gears which are disposed, in use, in the bores 16.
- Chamfer means 38 are provided at the open ends of the overlapping bores 16 and are discontinuous at respective points on the bores (one of which points is best seen in Figure 2), the discontinuities comprising circumferentially short (say 1 millimetre) integral projections 40 and 42.
- the separate end cover 14 has a non-circular spigot 50 formed on its inner end face 52, the end profile of the spigot comprising portions of two overlapping circles 54 smoothly interconnected by arcs 56 to form a waisted shape approximating to a figure of eight. These portions are a light interference fit of, say, 50 microns directly into the open ends of the overlapping bores 16 formed in the casing 10. Radius means 58 small enough to be accommodated within the space defined by the chamfer means 38 are provided between the inner end face 52 of the cover 14 and the spigot 50 formed thereon.
- the cover 14 has formed in it four clearance holes 60 adapted to be aligned with the four tapped holes 32 formed in the casing 10.
- Parallel bores 63 and 64 which are adapted to be accurately aligned with the parallel bores 36 are formed in the cover 14 for the purpose of accommodating bearings for the other end of the shafts carrying the gears which are disposed in the overlapping bores 16.
- the bore 62 is blind but the bore 64 passes completely through the cover 14 to enable one end of the associated shaft to project from the gear pump body so as to constitute the power input, the bore 64 being adapted to house oil seal means.
- the pump is assembled by mounting the bearings in the bores 36, 62 and 64 and the oil seal means in the bore 64, locating one end of the shafts in the bearings mounted in the bores 36, placing an O-ring in the groove 34, fitting the cover 14 over the other end of the shafts, and inserting four set-screws through the holes 60 into engagement with the holes 32.
- Tightening of the set-screws causes the spigot 50 to make a press fit into the adjacent ends of the overlapping bores 16, facilitated by the chamfer means 38, so that the bores 32, 62 and 64 are both accurately and firmly aligned; the O-ring in the groove 34 is compressed to seal the joint between the flat end face 30 of the casing 10 and the inner end face 52 of the cover 14; and the projections 40 and 42 are deformed so as to block the arcuate leakage paths from the outlet side to the inlet side of the pump which would otherwise exist between the chamfer means 38 and the radius means 58.
- the end profile of the spigot 50 needs not conform to the preferred shape described and illustrated herein but it must make close clearance fit, or, preferably, an interference fit with the open ends of the overlapping bores 16 in the casing 10.
- the projections 40 and 42 can be provided on the radius means 58 instead of on the chamfer means 38.
- the invention is equally well applicable to a hydraulic gear motor as to a gear pump.
Abstract
Description
Claims (4)
- A positive displacement hydraulic machine comprising a casing (10) in which there are formed overlapping bores (16) adapted to receive two gears for rotation in mesh with each other and one or more end covers (14) adapted to be located on the casing (10) characterised in that the one or more end covers are adapted to be located on the casing (10) by means of an integral non-circular spigot (50) which fits directly into the adjacent ends of the overlapping bores (16).
- A machine according to claim 1 in which the spigot (50) has an end profile which comprises portions of two overlapping circles (54) interconnected by arcs (56) to form a waisted shape.
- A machine according to claim 1 or claim 2 in which the spigot (50) is an interference fit in the adjacent ends of the overlapping bores (16).
- A machine according to any preceding claim in which the inside corner (58) where the base of the spigot meets the end cover is radiussed and the outside corner (38) where the overlapping bores meet the casing is correspondingly truncated so as to accommodate the radius and facilitate press-fitting of the cover into the casing.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB9506826 | 1995-04-01 | ||
GBGB9506826.8A GB9506826D0 (en) | 1995-04-01 | 1995-04-01 | An improvement in positive displacement hydraulic machines |
PCT/GB1996/000764 WO1996031701A1 (en) | 1995-04-01 | 1996-03-29 | Positive displacement hydraulic machines |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0819218A1 EP0819218A1 (en) | 1998-01-21 |
EP0819218B1 true EP0819218B1 (en) | 1999-05-12 |
Family
ID=10772392
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP96908244A Expired - Lifetime EP0819218B1 (en) | 1995-04-01 | 1996-03-29 | Positive displacement hydraulic machines |
Country Status (9)
Country | Link |
---|---|
EP (1) | EP0819218B1 (en) |
JP (1) | JPH11503213A (en) |
KR (1) | KR19980703498A (en) |
CN (1) | CN1185197A (en) |
AT (1) | ATE180043T1 (en) |
AU (1) | AU5156496A (en) |
DE (1) | DE69602435T2 (en) |
GB (1) | GB9506826D0 (en) |
WO (1) | WO1996031701A1 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20140128984A (en) * | 2012-01-05 | 2014-11-06 | 메르츠 노스 아메리카, 아이엔씨. | Skin lightening compositions |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2460957A (en) * | 1944-12-20 | 1949-02-08 | Joseph E Whitfield | Housing joint |
US2923248A (en) * | 1954-01-27 | 1960-02-02 | New York Air Brake Co | Pump |
JPS56104188A (en) * | 1980-01-23 | 1981-08-19 | Kayaba Ind Co Ltd | Gear pump or motor seal block support mechanism |
JPS5788U (en) * | 1980-05-30 | 1982-01-05 | ||
GB2247923B (en) * | 1990-09-15 | 1993-11-24 | Ultra Hydraulics Ltd | Rotary positive displacement hydraulic machines |
-
1995
- 1995-04-01 GB GBGB9506826.8A patent/GB9506826D0/en active Pending
-
1996
- 1996-03-29 DE DE69602435T patent/DE69602435T2/en not_active Expired - Fee Related
- 1996-03-29 CN CN96194082A patent/CN1185197A/en active Pending
- 1996-03-29 EP EP96908244A patent/EP0819218B1/en not_active Expired - Lifetime
- 1996-03-29 KR KR1019970706902A patent/KR19980703498A/en not_active Application Discontinuation
- 1996-03-29 AU AU51564/96A patent/AU5156496A/en not_active Abandoned
- 1996-03-29 JP JP8530074A patent/JPH11503213A/en active Pending
- 1996-03-29 WO PCT/GB1996/000764 patent/WO1996031701A1/en not_active Application Discontinuation
- 1996-03-29 AT AT96908244T patent/ATE180043T1/en not_active IP Right Cessation
Also Published As
Publication number | Publication date |
---|---|
DE69602435T2 (en) | 1999-11-25 |
JPH11503213A (en) | 1999-03-23 |
AU5156496A (en) | 1996-10-23 |
GB9506826D0 (en) | 1995-05-24 |
DE69602435D1 (en) | 1999-06-17 |
CN1185197A (en) | 1998-06-17 |
KR19980703498A (en) | 1998-11-05 |
ATE180043T1 (en) | 1999-05-15 |
EP0819218A1 (en) | 1998-01-21 |
WO1996031701A1 (en) | 1996-10-10 |
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