Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M59/00—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps
  • F02M59/02—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps of reciprocating-piston or reciprocating-cylinder type
  • F02M59/10—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps of reciprocating-piston or reciprocating-cylinder type characterised by the piston-drive
  • F02M59/102—Mechanical drive, e.g. tappets or cams
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C30/00—Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M59/00—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps
  • F02M59/44—Details, components parts, or accessories not provided for in, or of interest apart from, the apparatus of groups F02M59/02 - F02M59/42; Pumps having transducers, e.g. to measure displacement of pump rack or piston
  • F02M59/445—Selection of particular materials
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
  • F04B1/04—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement
  • F04B1/0404—Details or component parts
  • F04B1/0413—Cams
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M2200/00—Details of fuel-injection apparatus, not otherwise provided for
  • F02M2200/90—Selection of particular materials
  • F02M2200/9038—Coatings
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
  • F05C2253/00—Other material characteristics; Treatment of material
  • F05C2253/12—Coating

Definitions

• the invention relates to a high-pressure pump, in particular a radial or
• the invention relates to the field of fuel pumps for fuel injection systems of air-compression, self-igniting internal combustion engines.
• Fuel injection device of an internal combustion engine known.
• High-pressure pump has a pump housing, in which a pump element is arranged.
• the pump element comprises a driven by a drive shaft in a stroke pump piston.
• the pump piston is slidably guided in a cylinder bore of a part of the pump housing and limited in this one
• the pump piston is supported indirectly via a
• the plunger is slidably guided in a bore of a part of the pump housing in the direction of the longitudinal axis of the pump piston.
• a support element in which a roller is rotatably mounted, which rolls on the cam of the drive shaft.
• the axis of rotation of the roller is approximately parallel to the axis of rotation of the drive shaft.
• the support member has on its side facing the drive shaft a recess in which the roller is mounted.
• the high-pressure pump known from DE 10 2005 046 670 A1 has the disadvantage that during operation in the region of the roller damage due to near-surface outbreaks and the like can occur which impair the operation of the high-pressure pump and can lead to failure of the high-pressure pump.
• the high pressure pump according to the invention with the features of claim 1 has the advantage that an embodiment of the high pressure pump is improved. In particular, a reliable operation of the high pressure pump is possible even under difficult operating conditions.
• High-pressure pumps for air-compressing, self-igniting internal combustion engines also uses the diesel fuel as lubricant for the engine compartment.
• diesel fuel may contain corrosive components that degrade quality. Specifically, increased levels of free water may be included in the diesel fuel.
• corrosive diesel fuel When operating with such a corrosive diesel fuel, the use of ordinary rolling bearing steels on the roller and the running surface of the cam results in vibration cracking corrosion. These lead under load to shallow outbreaks and as a result, it can lead to a failure of the drive of the high-pressure pump.
• One conceivable solution is that completely stainless materials are used on the loaded components of the pump assembly, in particular the roller and the cam, which, however, represents a very cost-intensive solution.
• Rolling bearing steels can be reduced or avoided altogether.
• At least one corrosion protection layer is formed by a near-surface change of a material composition.
• a change of the metal alloy for example, on the running surface of the cam a
• Corrosion prevention can be achieved.
• alloying elements chromium and nickel can be used.
• Material composition is formed by ion implantation, by laser melting or by thermal spraying. During ion implantation, bombardment of the component surface results in the introduction of ions to change the alloy
• alloying is achieved by adding extraneous metal powder as a powder to the surface and reflowing.
• the aim of the laser reflow is an alloy change on the respective surface.
• thermal spraying the spraying of elements takes place at high temperature with the aim of deliberately changing the alloy of the component surface.
• At least one corrosion protection layer is formed as a passive layer. Specifically, a contact between the cam and the roller by means of a passive layer forming coating on the tread of the cam or the
• Roller surface are formed so that a corrosion prevention is achieved.
• the passive layer can be formed for example by a high content of chromium. Such a thin passive layer does not affect the essential properties, such as rolling resistance and resistance to abrasion, which are particularly important for continuous operation. In this case, it is also advantageous that a thin passive layer having a thickness of less than 1 ⁇ m is formed, in which, for example, chromium is applied as a passive layer former in order to achieve a significantly higher corrosion resistance.
• the passive layer may be provided specifically on the roller and / or the cam. As alloying elements, in particular chromium and nickel come into question. But other stainless steel alloys are possible.
• the coating of the component surface with a passive layer can be carried out in an advantageous manner by a plasma deposition, by a galvanization or by sputtering.
• a thin chromium layer can be formed with a thickness of less than 1 ⁇ .
• an average thickness of the passive layer, in particular the chromium layer is about 0.2 ⁇ .
• Passive layer are formed, which is similar to the chrome-plated passive layer.
• stainless steel alloys can be sputtered. It is advantageous that comparable physical properties result as with the base material.
• a heat treatment can also be carried out. This is also possible by laser melting.
• a base material for sputtering stainless steel in particular, a chromium steel or a chrome-nickel steel can be used.
• At least one corrosion protection layer is formed as a sacrificial layer.
• a sacrificial anode wherein the sacrificial anode is mounted as close as possible to, for example, the cam surface or the roller surface.
• the sacrificial layer may be formed as a thin layer.
• Sacrificial layer have a mean layer thickness of less than 2 ⁇ . Particularly advantageous is an average layer thickness of the sacrificial layer of less than 1 ⁇ . Especially in the operation of diesel fuel, which has a low conductivity, is the
• Sacrificial anode preferably mounted very close to the component to be protected or the surface to be protected.
• the complete component surface does not necessarily have to be coated.
• Coating options exist in particular on the outside of the cam and the roller, but also on the roller shoe in the bore area and on the front side. Specifically, it is therefore advantageous that the sacrificial layer is attached to an end face of the roller, to a side surface of the cam, to a side surface of the roller shoe, or in a bore portion of the roller shoe. In this case, a plurality of sacrificial layers can be provided.
• Fig. 1 is a high pressure pump in a schematic, axial sectional view
• Fig. 2 is a partial representation of the high-pressure pump shown in FIG. 1 in a schematic representation according to a further embodiment of the
• Fig. 1 shows a high pressure pump 1 in a schematic, axial sectional view according to an embodiment of the invention.
• the high pressure pump 1 can be configured in particular as a radial or inline piston pump.
• the high-pressure pump 1 is suitable as a fuel pump for fuel injection systems of
• a preferred use of the high-pressure pump 1 is for a fuel injection system with a common rail that stores diesel fuel under high pressure.
• the high-pressure pump 1 according to the invention is also suitable for other applications.
• the high-pressure pump 1 has a multipart pump housing 2 with a housing part 3 and a flange 4.
• the pump housing 2 has a bore 5.
• a pump assembly 6 is arranged in the area of the bore 5.
• the high-pressure pump 1 has a drive shaft 7 which is mounted in the pump housing 2.
• the drive shaft 7 mounted on the one hand at a bearing point 8 in the housing part 3 and on the other hand at a bearing point 9 on the flange 4.
• the drive shaft 7 has a cam 10 which is arranged between the bearings 8, 9.
• a side surface 1 1 of the cam 10 of the bearing 9 faces, while another side surface 12 of the cam 10 faces the bearing 8.
• the cam 10 may be designed as a single or multiple cam 10. It is also possible that the cam 10 by an eccentric portion of
• the drive shaft 7 rotates with the cam 10 about an axis of rotation 13. This results in a periodic lifting movement of the cam 1, via which the pump assembly 6 can be driven.
• the high-pressure pump 1 has a cylinder head 15, which is connected in a suitable manner to the pump housing 2.
• the cylinder head 15 comprises a projection 16 which projects into the bore 5 of the pump housing 2.
• the cylinder head 15 has a cylinder bore 17 which extends through the projection 16. In the cylinder bore 17 is a
• Pump piston 18 is arranged, which is guided along an axis 19 of the cylinder bore 17 slidably in the cylinder bore 17.
• the pump piston 18 limits a pump working chamber 20 in the cylinder bore 17.
• an outlet valve 22 is provided, via which the high-pressure fuel in a fuel line 23 and via this to a common rail or the like can be performed.
• the pump assembly 6 has a hollow cylindrical plunger body 24 which is guided in the bore 5 along the axis 19 of the pump assembly 6.
• a driving element 25 is inserted, which engages behind a collar 26 of the pump piston 18.
• the driving element 24 inserted in the plunger body 24 is acted upon by a plunger spring 27.
• a roller shoe 30 is inserted.
• the roller shoe 30 forms at its bore portion 44 a semi-open plain bearing for a roller 31st
• the roller 31 is mounted in the roller shoe 30, wherein the roller 31 is rotatable about a rotational axis 32 of the roller 31.
• the roller 31 has a surface 33 with which the roller 31 bears against a running surface 34 of the cam 10 formed by the bore 44.
• the roller 31 has end faces 35, 36.
• the roller shoe 30 has a bearing surface 37 on which the roller 31 is mounted in the roller shoe 30. During operation of the high-pressure pump 1, the roller 31 runs on the running surface 34 of the cam 10.
• one or more corrosion protection layers on the roller 31 one or more Corrosion protection layers on the roller shoe 30 and / or one or more
• Corrosion protection layers on the cam 10 is provided.
• a corrosion protection layer may be formed on the surface 33 of the roller 31. This is due to a change in the metal alloy in the field of
• a change of the metal alloy in the region of the running surface 34 of the cam 10 may be provided. It is also possible to change the metal alloy in the area of the bearing surface 37 of the roller shoe 30.
• the alloying elements used are preferably chromium and nickel. By changing the alloy on the component surface, a thin edge layer can be produced, so that a significantly higher corrosion resistance is achieved.
• this may relate to the roller 31 and the cam 10.
• Passive layer Such a passive layer forming coating can be formed for example by a high chromium content.
• the preferably very thin passive layer in this case does not affect the essential properties, in particular the rolling resistance and the Abrassionsfesttechnik. This can be due to the use of an expensive, stainless
• the high-pressure pump 1 can also be operated with corrosive diesel fuels and the like.
• the very thin passive layer preferably covers the entire part of the component surface to which a corrosion protection of this kind is required.
• the layer thickness is preferably less than 1 ⁇ m.
• Passive layer forming done. However, it can also chromium and nickel as
• the entire surface 33 of the roller 31 may be provided with a passive layer.
• the entire running surface 34 of the cam 10 can also be provided with a passive layer. To design the passive layer, a
• Plasma deposition, electroplating or sputtering serve.
• Fig. 2 shows a partial, schematic representation of a high-pressure pump 1 according to a further embodiment.
• the roller shoe 30, the roller 31 and the drive shaft 7 are shown with the cam 10.
• Embodiment a half-shell 45 is inserted into the roller shoe 30.
• Half shell 45 may be formed of a bearing steel. This is a
• a coating of the roller shoe 30 can be omitted.
• a coating may be limited specifically to the running surface 34 of the cam 10 and the surface 33 of the roller 31 in this case.
• a sacrificial anode Another possibility to achieve a corrosion prevention on the affected surfaces, is the design of a sacrificial anode.
• a sacrificial anode is attached as close as possible to the affected surfaces. For example, allows a very thin layer of a sacrificial material on the component surface sufficient corrosion protection. Such a sacrificial layer then protects the component from damaging
• the sacrificial layer By a very thin design of the sacrificial layer, the essential properties, in particular the rolling resistance and Abrassionsfesttechnik not affected.
• the sacrificial layer is thinner than 2 ⁇ , in particular thinner than 1 ⁇ configured.
• the sacrificial layer may be based on the sacrificial material zinc. The sacrificial material zinc then serves as a sacrificial anode.
• the complete component surface does not necessarily have to be coated.
• the side surfaces 1 1, 12 of the cam 10 may be provided with a sacrificial layer to specifically protect the running surface 34 of the cam 10.
• the end faces 35, 36 of the roller 31 may be provided with a sacrificial layer in order to protect the surface 33 of the roller 31 in a targeted manner.
• side surfaces 46, 47 of the roller shoe 30 it is also possible for side surfaces 46, 47 of the roller shoe 30 to be coated with a sacrificial layer in order to protect the bearing surface 37 of the roller shoe 30 in a targeted manner.
• the half-shell 45 can then be omitted or formed from a cost-effective material, in particular an ordinary rolling bearing steel.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Combustion & Propulsion (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Materials Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Fuel-Injection Apparatus (AREA)
• Coating By Spraying Or Casting (AREA)

Applications Claiming Priority (2)

Publications (1)

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Family Applications (1)

Country Status (5)

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Citations (2)

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• 2010
  • 2010-04-13 DE DE102010003886A patent/DE102010003886A1/de not_active Withdrawn
• 2011
  • 2011-03-02 CN CN201180018671.5A patent/CN102859177B/zh not_active Expired - Fee Related
  • 2011-03-02 WO PCT/EP2011/053095 patent/WO2011128149A1/de active Application Filing
  • 2011-03-02 RU RU2012147919/06A patent/RU2567529C2/ru not_active IP Right Cessation
  • 2011-03-02 EP EP11709034A patent/EP2558706A1/de not_active Ceased

Patent Citations (2)

Non-Patent Citations (1)

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