Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D29/00—Details, component parts, or accessories
  • F04D29/02—Selection of particular materials
  • F04D29/026—Selection of particular materials especially adapted for liquid pumps
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D5/00—Pumps with circumferential or transverse flow
  • F04D5/002—Regenerative pumps
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2300/00—Materials; Properties thereof
  • F05D2300/20—Oxide or non-oxide ceramics
  • F05D2300/22—Non-oxide ceramics
  • F05D2300/228—Nitrides
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2300/00—Materials; Properties thereof
  • F05D2300/60—Properties or characteristics given to material by treatment or manufacturing
  • F05D2300/611—Coating

Definitions

• the invention relates to a pump, in particular a fuel pump, with a pump housing, in which a pump chamber is formed, to which an inlet leads and from which an outlet leads, with a pump wheel arranged in the pump chamber and fastened on a rotatably drivable drive shaft is, which is rotatably mounted in bearings in the pump housing.
• the fuels are increasingly contaminated today, which lead to wear between the parts of the pumps which are moved relative to one another and which damage the anodized layer. Contamination of the fuels by water or chemically similar reacting substances as well as additions of fuels of various types can then lead to further damage to the pump parts.
• the object of the invention is therefore to provide a pump of the type mentioned at the outset, which is of simple construction and has low wear and permanently ensures high pressure build-up.
• this object is achieved in that surfaces of the pump chamber which are in contact with surfaces of the pump wheel and / or surfaces of the pump wheel which are in contact with surfaces of the pump chamber have a coating of low thickness and great hardness which is applied by physical deposition from the gas phase.
• the thin coating can be applied with a precisely uniform thickness and thus enables the maintenance of small tolerances, so that a good pressure build-up of the pump is guaranteed.
• the great hardness protects the coating against wear and ensures a long service life of the pump.
• This hardness can preferably be in a range from 2500 HV to 3500 HV (Vickers hardness) but also above or below.
• the coating can still be applied to a wide variety of materials, the optimum materials and material pairs can be used for the pump housing and impeller.
• the layer is applied in a manner which does not pollute the environment.
• the drive shaft is rotatably mounted in the bearing bores of the pump housing, the bearing bores and / or the drive shaft having a coating of small thickness and great hardness applied by physical deposition from the gas phase.
• the very hard and smooth surface of the coating on the bearing bore and / or drive shaft and the narrow tolerances mean that these parts transfer the positive properties of a carbon bushing as a bearing directly into the simple bearing bore. This saves separate bearings and their processing. If the pump is a flow pump, then the narrow tolerances of the components, which are absolutely necessary in flow pumps for the pressure build-up, and thus small gaps between the components moving relative to one another can be minimized.
• the flow pump is a peripheral wheel or side channel pump.
• the entire surface of the pump chamber can be provided with a coating applied by physical deposition from the gas phase, preferably also the surfaces of the fuel-carrying parts of the pump with a physical deposition from the Gas phase applied coating are provided. This means that even aggressive media can be conveyed by the pump without causing damage.
• the tight manufacturing tolerances can be ensured by the coating having a thickness of approximately 2 ⁇ m to approximately 5 ⁇ m.
• a layer thickness of 2 ⁇ m is completely sufficient for wear protection, while 5 ⁇ m is preferable for corrosion protection.
• the coating is preferably a chromium nitride layer.
• the pump housing and / or pump wheel can be made of metal or a metal alloy, in particular aluminum or an aluminum alloy, which become wear-resistant and corrosion-resistant due to the coating, while maintaining the ease of manufacture and the low weight.
• the pump housing and / or pump wheel consist of a plastic, in particular a phenolic resin. Even parts of low weight, which are easy to manufacture as injection molded parts, become wear-resistant and resistant to aggressive media through the coating.
• the pump housing is made of coated aluminum and the pump wheel is made of phenolic resin.
• the pump wheel made of phenolic resin can be coated or uncoated.
• the pump shown is a two-stage fuel pump.
• a drive shaft 2 is rotatably attached to an electric motor arranged in the closed motor housing 1. drivable, on the right end region of which a first pump wheel 3 of a peripheral wheel pump 14 is arranged in a rotationally fixed manner.
• the radially circumferential area of the first pump wheel 3 is formed with a first blade ring, which is largely enclosed by an annular channel.
• a first pump chamber 5 is designed as a cup-shaped recess 31 in one end face of a cover 6, which is part of the pump housing 7.
• a ball 9 is arranged centrally in a receptacle on the side of the first pump wheel 3 in the cover 6, on which the drive shaft 2 is supported on the end face and which forms an axial bearing of the drive shaft 2.
• the first pump chamber 5 is closed by an intermediate wall 10 which bears against the mouth opening of the pot-shaped recess 31 of the cover 6 and through which the drive shaft is guided.
• the drive shaft 2 is guided through a bearing bore 11 in the intermediate wall 10, which also forms part of the pump housing 7, and is directly rotatably supported in this bearing bore 11.
• the first pump chamber 5 is connected to a radially circumferential annular channel 12 on the side facing the peripheral wheel pump 14 in the intermediate wall 10, from which a connection 13 leads to the side of the intermediate wall 10 facing away from the peripheral wheel pump 14
• a side channel pump 16 opens into a first side channel 15, which is annular there.
• the intermediate wall 10 is also formed on the side of the first side channel 15 with a cup-shaped recess 17, which forms a second pump chamber and in which a second pump wheel 18 of the side channel pump 16 is arranged, which is also non-rotatably seated on the drive shaft 2.
• the second impeller 18 has in its one side surface covering the first side channel 16 a second blade ring 19 which is connected via axial openings 20 to a third blade ring 21 on the other side surface of the pump wheel 18.
• the third blade ring 21 is covered by an annular second side channel 22 which is formed in a partition 23 which closes the cup-shaped opening 14, forms part of the pump housing 7 and is guided through a drive shaft 2.
• the partition 23 separates the side channel pump 16 from the motor housing 1, the outlet 24 formed in the partition 23 opening into the motor housing 1.
• the fuel delivered flows through the motor housing 1 and is fed via a check valve 25 to a pressure connection 26 of the fuel pump, which are arranged in a closure wall 29.
• a plug contact 30 of the power supply of the electric motor is also located in the closure wall 29.
• a bearing wall 27 is arranged which, coaxially with the first bearing bore 11, has a second bearing bore 28 in which the left end of the drive shaft 2 is directly rotatably mounted.
• the two pump wheels 3 and 18 are made of phenolic resin.
• the parts of the pump housing 7 are made of aluminum.
• the cover 6 has a coating of chromium nitride in all areas facing the intermediate wall 10 and in the inlet 8.
• the intermediate wall 10, the partition wall 23 and the bearing wall 27 are completely provided with a coating of chromium nitride.
• the surfaces of the closure wall 29 and the pressure connection 26 which are flushed with fuel are coated with chromium nitride.
• the cylindrical inner walls of the first and second bearing bores 11 and 28 are also coated.
• the drive shaft 2 made of steel has a chromium nitride coating in its areas located in the bearing bores 11 and 28.
• chrome nitride coatings are applied by physical vapor deposition and have a thickness of 5 ⁇ m and a Vickers hardness of approximately 2500 HV.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)
• Compressor (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=7712249

Family Applications (1)

Country Status (7)

Families Citing this family (4)

Citations (4)

Family Cites Families (7)

• 2002
  • 2002-01-15 DE DE10201405A patent/DE10201405A1/de not_active Ceased
  • 2002-12-20 BR BRPI0215501-0A patent/BR0215501B1/pt not_active IP Right Cessation
  • 2002-12-20 CN CNA028228332A patent/CN1589373A/zh active Pending
  • 2002-12-20 WO PCT/DE2002/004702 patent/WO2003060328A1/de active IP Right Grant
  • 2002-12-20 DE DE50209806T patent/DE50209806D1/de not_active Expired - Lifetime
  • 2002-12-20 ES ES02795028T patent/ES2280609T3/es not_active Expired - Lifetime
  • 2002-12-20 EP EP02795028A patent/EP1466099B1/de not_active Expired - Fee Related
• 2003
  • 2003-01-14 US US10/341,593 patent/US20030175110A1/en not_active Abandoned

Patent Citations (4)

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