Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16N—LUBRICATING
  • F16N13/00—Lubricating-pumps
  • F16N13/20—Rotary pumps
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01C—ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES
  • F01C21/00—Component parts, details or accessories not provided for in groups F01C1/00 - F01C20/00
  • F01C21/02—Arrangements of bearings
• • 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
  • F04C15/0088—Lubrication
• • 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
  • F04C15/0096—Heating; Cooling
• • 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
  • F04C2/18—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 with similar tooth forms
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16N—LUBRICATING
  • F16N39/00—Arrangements for conditioning of lubricants in the lubricating system
  • F16N39/02—Arrangements for conditioning of lubricants in the lubricating system by cooling

Definitions

• This invention relates to lubrication systems for hydraulic pumps, and more particularly, to lubricating systems for bearings in external gear pumps.
• the fluid serves to cool the bearings.
• High pressure bearing lubrication in which high pressure hydraulic fluid, that leaks past the pressure plate surface of the pump near the roots of the gear teeth, flows down the lengths of the journals and bearings supporting the gear and is collected at the outer ends of the journals. Fluid then flows through bearing drain passages in the pump housing and back to the inlet of the pump.
• the pressure plates may also incorporate lubrication grooves to ensure adequate flow rates from the discharge side of the pump to the journals and bearings.
• the present invention is directed to a system for pumping hydraulic fluid to drive a hydraulic device, wherein the system comprises at least one rotary pump element having at least a first journal extending therefrom.
• the rotary pump element is positioned in a pumping chamber of a housing, wherein the housing has an inlet opening and a discharge opening connected to the pumping chamber.
• the housing includes at least a first bearing for supporting the journal of the pump element.
• Hydraulic fluid pumped by the pump is returned to the inlet opening by a return line after having driven the hydraulic device.
• a heat exchanger is connected between the return line and the bearing for the gear journal by a lubrication line to cool returning hydraulic fluid prior to using the fluid for lubrication of the bearing journal.
• the pump element is a gear and the lubrication line communicates with a chamber at an end of the journal distal from the gear.
• the pump element includes a second journal extending in a direction opposite the first journal and the housing includes a second bearing for supporting the second journal, the second journal and second bearing being connected receive lubrication fluid from the lubrication line.
• the second journal is connected to the lubrication line by a bore which extends through the first and second journals, as well as the pump element.
• Figure 1 is a schematic view of a lubrication system in accordance with the present invention in combination with one gear of a gear pump;
• Figure 2 is a side elevation of one embodiment of a gear pump employing the hydraulic pump lubrication system in accordance with the present invention
• Figure 3 is an elevation taken along lines 3-3 of Figure 2.
• gear pump 10 having a housing 12 with a discharge opening 14 and an inlet opening 16, both in communication with pumping chamber 18.
• the pumping chamber 18 has two gears therein, only one of which is shown, gear 20.
• one of the gears of the gear pump is driven gear (not shown) and the other gear is an idler gear (such as the gear 20) arranged, for example, like the gears in U.S. Patent 4,553,915 to Eley, incorporated herein by reference.
• the gear 20 includes gear teeth 22 which are mounted on the hub 24 and include flank portions 26 and root portions 28.
• the hub 24 of the gear 20 has a first gear journal 30 projecting from one side and a second gear journal 32 projecting from the other side.
• the gear journals 30 and 32 rotationally support the gear 20 in bearings 34 and 36, respectively, seated in the housing 12.
• Hydraulic fluid illustrated by the arrow 40 is pumped from the discharge opening 14 to a driven device 42, such as a motor or hydraulic cylinder and is returned via a return line 44 to tank 46. From tank 46, the fluid is returned by line 48 through the inlet opening 16 of the housing 12. If the temperature of the hydraulic fluid in the tank 46 exceeds the rated temperature level of pump 10, for example, 210°F, it should not be returned to the pump because, since it is used to lubricate the pump, it can damage the bearings 34 and 36 of the pump by overheating the bearings. For at least some operations, hydraulic fluid is at an elevated temperature of, for example, 250°F.
• a heat exchanger 50 is connected between the return line 44 and a lubrication line 52.
• the lubrication line 52 is in turn connected to a lubrication passage 54 in the housing 12 which is in turn connected to a lubrication cavity 56 disposed at the free end 58 of the gear journal 30. Accordingly, a small portion of the return fluid in return line 44 is cooled by the heat exchanger 50 and placed in proximity with the gear journal 30 and the bearing 34.
• the interface 60 between the gear journal and bearing 34 includes interstices, such as spaces between roller bearing elements, which allow the cool hydraulic fluid to flow from the lubrication cavity 56, between the gear joumal 30 and bearing 34 and back to the pumping chamber 18.
• This flow through the interface 60 is due to a low pressure region 65 communicating with the interface 60 in the gear pump chamber 18 at the location where the gear 20 demeshes from the drive gear (not shown in Figure 1).
• the hydraulic fluid flowing into the low pressure region 65 joins the hydraulic fluid entering the inlet opening 16 from the inlet line 48 for pumping out through the discharge opening 14.
• gear journal 32 which projects opposite the gear joumal 30 from the hub 24, is lubricated with cool lubricant which flows through a bore 66 that extends through the gear journal 30, the hub 24 and the gear journal 32 into a second lubrication cavity 67 at the free end 68 of the second gear journal 32. Cool lubricant then flows from the lubrication cavity 67 back through the interstices of the interface 70 between the second gear journal 32 and the second bearing 36. Again, the lubricant in the interface 70 flows into the low pressure region 65 of the pumping chamber 18 because the pressure in space 67 is higher than the pressure in the low pressure region.
• the hydraulic fluid that has lubricated gear journal 32 and bearing 36 then joins the hydraulic fluid in inlet opening 16 and is discharged through discharge opening 14.
• FIG. 2 and 3 there is shown an embodiment of the invention in which a pair of gear pumps 80 and 82, driven by a single input shaft 83, pump hydraulic fluid in a parallel arrangement.
• the pump 80 has a drive gear 84 and an idler gear 85, while the pump 82 has a drive gear 86 and an idler gear 87.
• the drive gear 84 is coupled to the drive gear 86 with a coupling 88.
• the gears 84-86 have teeth 90 which mesh at areas 91 so that the driving gears 84 and 86 both drive the idler gears 85 and 87 and accomplish a pumping function by carrying the fluid from an inlet 92 (only one of which is shown in Figure 3) to an outlet 93.
• first gear journals 30a, 30b, 30c and 30d correspond to the gear journal 30 of Figure 1
• second gear journals 32a, 32b, 32c and 32d correspond to the second gear joumal 32 of Figure 1.
• hydraulic fluid flows through interfaces 60a and 70a, 60b and 70b, and 60c and 70c, and 60d and 70d, to the inlet region 92 via bleed grooves 94 (see Figure 3), which provides the low pressure regions 65a and 65b for drawing the hydraulic fluid along the interfaces 60 and 70.
• the idler gears 85 and 87 In order to transport the hydraulic fluid from the coupling cavity 104, the idler gears 85 and 87 have bores 66b and 66d which extend through the hubs 24b and 24b thereof (as well as through the journals 30b and 32b and 30d and 32d) in order to take the fluid to outside lubrication chambers 67b and 67d.
• Lubrication chambers 67b and 67d communicate with lubrication chambers 67a and 67c to convey the cooled lubricant to the drive gears 84 and 86.
• a second heat exchanger 110 is disposed in the lubrication line 104.

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• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Rotary Pumps (AREA)

Applications Claiming Priority (3)

Publications (2)

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Family Applications (1)

Country Status (4)

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Family Cites Families (3)

• 1999
  • 1999-09-28 WO PCT/US1999/022316 patent/WO2000019067A2/en not_active Ceased
  • 1999-09-28 EP EP99948470A patent/EP1055053A4/de not_active Withdrawn
  • 1999-09-28 JP JP2000572491A patent/JP2002525529A/ja active Pending
  • 1999-09-28 CA CA002309458A patent/CA2309458A1/en not_active Abandoned

Non-Patent Citations (2)

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