Classifications

• • 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
• • 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
• • 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
  • F02M37/00—Apparatus or systems for feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus; Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines
  • F02M37/04—Feeding by means of driven pumps
• • 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
  • F04B1/0443—Draining of the housing; Arrangements for handling leaked fluids

Definitions

• the invention relates to a fuel pump for delivering fuel for an internal combustion engine according to the preamble of claim 1.
• the fuel supplied to the internal combustion engine must increasingly be supplied to the internal combustion engine at a relatively high pressure.
• the drive means used to drive the pump element is subjected to great mechanical forces.
• the load on the bearings bearing the drive means is relatively high.
• the drive means is usually a shaft with a rotary bearing and the bearings are heavily loaded in the radial direction. Because the fuel has no or an extremely poor lubricating property, but rather can seriously damage the bearing, it must be prevented that the fuel gets into the area of the bearing. This is especially true when the fuel is gasoline.
• the bearing is usually provided with a special lubricant. So that the lubricant does not run out a bearing seal is provided.
• the bearing seal must be matched to the lubricant. If the fuel gets into the area of the bearing seal, the fuel can adversely affect the properties of the bearing seal, especially if the fuel is petrol.
• the drive means is a shaft which is rotatably supported by two ball bearings. External lubrication is provided for this fuel pump.
• lubricant is pressed between the two ball bearings via a lubricant supply opening. This requires a separate source of lubricant to deliver the lubricant. This increases the effort considerably.
• the bearing seal used to seal the ball bearing comes into contact with the fuel on one side, which impairs the service life of the bearing seal. Because the bearing seal cannot seal absolutely, at least the smallest amounts of fuel can always reach the area of the ball bearings, which affects their durability.
• the fuel pump according to the invention for pumping fuel for an internal combustion engine with the characterizing features of claim 1 has in contrast the advantage that the fuel is excellently separated from the bearing storing the drive means, which has a favorable effect on the durability of the bearing. Leakage of the fuel from the housing of the fuel pump is advantageously reliably prevented even without complex sealing measures.
• the fuel pump can advantageously be constructed in a structurally simple manner and the connection of the separating chamber to the air at least indirectly conveyed by the internal combustion engine is particularly simple.
• Air is required for the operation of the internal combustion engine, which air is conveyed by the internal combustion engine, so that advantageously at least a small part of this air can be passed through the separation space without great effort.
• the separating chamber is connected to the air inlet of the internal combustion engine, this has the advantage that any fuel that enters the separating chamber can be easily discharged into the internal combustion engine and can be burned harmlessly.
• the separation space is additionally provided with an entrance through which air can enter the separation space, then is advantageously obtained by flushing the separation space with air.
• Separation space and the amount of air flowing through can be influenced in an advantageous manner.
• the throttle provided upstream in front of the entrance to the separation space can also advantageously influence the pressure in the separation space or the flushing of the separation space with air.
• Oil is advantageously particularly well suited as a release agent.
• an internal combustion engine lubrication system is usually provided to supply various bearing points with oil. With this internal combustion engine lubrication, oil can advantageously be passed through the separation chamber particularly easily.
• the throttle between the separating space and the internal combustion engine lubrication can advantageously influence the pressure in the separating space or the amount of oil that is conveyed through the separating space without great effort.
• FIG. 1 shows a longitudinal section through an exemplary selected fuel pump and FIGS. 2 to 4 in symbolic form preferably selected, different exemplary embodiments for connecting the separation space. Description of the embodiments
• the fuel pump is used to deliver fuel required by an internal combustion engine.
• the fuel pump designed according to the invention works, for example, according to the displacement principle.
• a fuel pump operating on the displacement principle usually has one or more pump elements.
• the pump element has, for example, a reciprocating piston or, for example, rotating displacement spaces that increase and decrease during rotation.
• the pump element or pump elements are driven by a drive means.
• the drive means is, for example, a reciprocating rod or a rotatably mounted shaft.
• the fuel pump has a low pressure side and a high pressure side.
• the at least one pump element delivers fuel from the low pressure side to the high pressure side.
• the fuel pump designed according to the invention is particularly well suited for those internal combustion engines in which the fuel has to be delivered under high pressure.
• the fuel is, for example
• Diesel or petrol If the fuel is petrol, then the particular advantages of the fuel pump designed according to the invention are particularly advantageously noticeable because petrol, if it came into the area of bearings, has a negative effect on the Materials of the bearing and the seal for sealing the bearing can affect.
• a fuel pump is selected for the preferred embodiment described below, which works on the principle of a radial piston pump, has a shaft mounted on one side as a drive as the drive means and has three pump elements for conveying the fuel.
• the preferably selected fuel pump has a so-called floating bearing of the drive means.
• the drive means embodied in the form of a rotationally mounted shaft can also be mounted on both sides of the three pump elements.
• FIG. 1 shows, by way of example, a sectional plane of a longitudinal section through a fuel pump 2, which is preferably selected and is designed in accordance with the invention.
• the fuel pump 2, selected as an example, has three
• Pump elements one of the three pump elements being visible in the sectional plane shown, and the other two pump elements being located below or above the sectional plane shown.
• the fuel pump 2 essentially comprises a housing 4, a low-pressure connection 6, a high-pressure connection 8, a pump element 10, a drive means 12, a bearing 14, a fuel chamber 16, a seal 18 and a separation chamber 20.
• the drive means 12 essentially comprises a shaft 12a, a pulley 12b, a rotary driver 12c, a fastening means 12d, an eccentric shaft piece I2e, a sliding disk 12g and a lifting piece 12h.
• the shaft 12a of the drive means 12 is rotatably supported in the housing 4 by means of the bearing 14.
• the pulley 12b is connected in a rotationally fixed manner by means of the rotary driver 12c.
• the rotary driver 12c is, for example, a feather key which engages in a groove provided in the shaft 12a and in the pulley 12b.
• the fastener 12d is, for example, a nut that holds the pulley 12b on the shaft 12a.
• the belt pulley 12b is connected to a belt 22
• Internal combustion engine 24 (Fig. 2) connected in terms of drive.
• the internal combustion engine 24 rotates the shaft 12 a of the drive means 12 in the housing 4 via the belt 22.
• the bearing 14 essentially comprises a first roller bearing 14a, a second roller bearing 14b, a first bearing seal 14c, a second bearing seal 14d, a bearing space 14e and a bearing shell 14f.
• the bearing 14 can comprise, for example, a plain bearing instead of the roller bearings 14a, 14b.
• roller bearings 14a, 14b are used for the radial mounting of the shaft 12a and include, for example, balls which are on the one hand on the shaft 12a and on the other hand on the
• Support bearing shell 1 f To improve the bearing 14, circumferential grooves are provided in the shaft 12a, in which the balls of the roller bearings 14a, 14b are guided. Axial mounting of the shaft 12a is also possible via these circumferential grooves.
• the bearing shell 14f is firmly pressed into the housing 4 on its outer circumference.
• the bearing space 14e is a cavity between the shaft 12a, the bearing shell 14f and the bearing seals 14c, 14d.
• the first bearing seal 14c provides for sealing the storage space 14e with respect to the separating space 20.
• the second storage seal 14d seals the storage space 14e from the outside.
• the eccentric shaft piece 12e is eccentric to the
• the sliding disc 12g is arranged, on which the lifting piece 12h is mounted.
• a rotary movement of the shaft 12a leads to a lifting movement of the lifting piece 12h transverse to the axis of rotation of the shaft 12a.
• the preferably selected, exemplarily illustrated pump element 10 essentially includes a piston 10a, a Koblen Adjust 10b, a sliding block 10c, a pressure chamber 10d, a holding cartridge 10e, a spring 10f, a low pressure valve 10g and a high pressure valve 10h.
• the holding cartridge 10e is held in the housing 4 by means of a bead 10i.
• a further flanging 10k holds the piston guide 10b in the holding cartridge 10e.
• the piston 10a is slidably mounted in the piston guide 10b.
• the piston 10a has a front end facing the lifting piece 12h.
• the sliding block 10c is fastened to the end face of the piston 10a facing the lifting piece 12h.
• the spring 10f is clamped between the holding cartridge 10e and the slide shoe 10c.
• the spring 10f presses the sliding block 10c against the lifting piece 12h. During one Extending movement of the piston 10a, the spring 10f holds the sliding block 10c in contact with the lifting piece 12h.
• the low-pressure connection 6 is connected to the fuel chamber 16 via a channel running in the housing 4. There is a longitudinal bore 10m in the piston 10a. The bore 10m is connected to the fuel chamber 16 via a transverse bore running across the piston 10a.
• the pressure chamber 10d is located inside the holding cartridge 10e. From the fuel chamber 16, the fuel passes through the bore 10m, through the low pressure valve 10g, into the pressure chamber 10d.
• the low pressure valve 10g is a check valve which allows the fuel to flow from the fuel chamber 16 into the pressure chamber 10d, but prevents the fuel from flowing in the opposite direction. From the pressure chamber 10d, the fuel passes through the high-pressure valve 10h, through angled channels 10n provided in the housing 4 to the high-pressure connection 8.
• the high-pressure valve 10h allows the fuel to flow out of the pressure chamber 10d in the direction of the high-pressure connection 8, but an opposite direction of flow is caused by the high pressure valve prevents 10h.
• the piston 10a executes entry and exit strokes.
• fuel passes from the fuel chamber 16 through the low pressure valve 10g into the pressure chamber 10d.
• the fuel is displaced from the pressure chamber 10d and reaches the high-pressure connection 8 under pressure through the high-pressure valve 10h, through the channels 10n.
• the fuel comes from a fuel tank 26 (Fig. 2) through the low pressure port 6 in the Fuel chamber 16 (Fig. 1). Between the fuel tank 26 (Fig. 2) through the low pressure port 6 in the Fuel chamber 16 (Fig. 1). Between the fuel tank 26 (Fig. 2) through the low pressure port 6 in the Fuel chamber 16 (Fig. 1). Between the fuel tank 26 (Fig. 2) through the low pressure port 6 in the Fuel chamber 16 (Fig. 1). Between the fuel tank 26 (Fig. 2) through the low pressure port 6 in the Fuel chamber 16 (Fig. 1). Between the
• the pressure in the fuel chamber 16 is higher than the atmospheric pressure.
• the seal 18 seals between the separating space 20 and the fuel space 16.
• a ring 18 a pressed into the housing 4 holds the seal 18 in the housing 4.
• the seal 18 is a circumferential lip seal in the illustrated embodiment.
• the seal 18 can, for example, also be a grooved ring, an O-ring, a rectangular ring or another
• the seal 18 is preferably designed so that the smallest possible friction occurs when the shaft 12a rotates between the seal 18 and the shaft 12a.
• the seal 18 is intended to prevent fuel from getting into the separation space 20 from the fuel space 16.
• the seal 18 does not have to seal in the opposite direction. Therefore, and because of the desired low friction, the lip seal shown in the drawing is particularly useful. Because a small leakage of fuel from the fuel compartment 16 in the
• Separation space 20 does not interfere with the operation of either the fuel pump 2 or the internal combustion engine 24, a very low pressing force of the seal 18 against the shaft 12a is sufficient.
• the low leakage of fuel from the fuel chamber 16 into the separation chamber 20 is due to the reduction in friction and because of the heat dissipation rather favorable for the durability of the seal 18.
• the seal can for example be firmly connected to the shaft of the drive means and slide on a hole wall in the housing.
• the separating space 20 can be connected in the exemplary embodiment shown in FIG. 1, preferably selected, via a first connection 20a and via a second connection 20b.
• the connections 20a, 20b lead out of the area of the separation space 20 through the housing 4.
• the separation space 20 is drawn relatively large in the drawing in the axial direction and in the radial direction for clarity. It should be noted that the separation space 20 can be dimensioned quite small in the axial direction (in the direction of the axis of rotation of the shaft 12a) and in the radial direction (perpendicular to the axis of rotation of the shaft 12a), so that the size of the fuel pump 2 hardly or only slightly enlarged.
• FIG. 2 shows a greatly simplified, schematic, symbolic side view of the fuel pump 2.
• the separation space 20 is not visible in the side view and is therefore symbolically indicated in FIG. 2 with broken lines.
• a low pressure line 6a leads from the fuel reservoir 26 to the low pressure connection 6 of the fuel pump 2.
• a high pressure line 8a leads to a fuel metering device 28.
• the fuel metering device 28 comprises, for example, a fuel collection pipe and a fuel injection valve or a plurality of fuel injection valves. Via the fuel injection valves of the fuel metering device 28, the fuel reaches the combustion chambers of the internal combustion engine 24, which are not shown in the drawing.
• the internal combustion engine 24 selected as an example for the exemplary embodiment has an air inlet 30
• Air inlet 30 includes, for example, an air inlet point 30a, an air filter 30b, an intake manifold 30c and a throttle valve 3 Od.
• FIG. 2 shows a cover 20c, an opening 20d, a line 20e, a filter screen 20f, a throttle point 20g, a line 20h and a throttle point 20i.
• the line 20e leads from the opening 20d, through the filter 20f, through the throttle point 20g, through the connection 20b, into the separation space 20.
• the line 20h leads from the separation space 20, through the connection 20a, through the throttle point 20i, to the air inlet 30.
• the line 20h is connected between the air filter 30b and the throttle valve 30d to the inside of the intake manifold 30c.
• the cover 20c is provided so that no splash water and no dirt get into the separation space 20.
• the filter screen 20f and / or the cover 20c may be dispensed with.
• the amount of air flowing from the environment into the separation space 20 can be influenced with the throttle point 20g.
• the cover 20c, the filter 20f and the throttle point 20g are shown in FIG. 2 as separate components provided in the line 20e shown.
• the throttle point 20g can also be produced by appropriately dimensioning the bore or line 20e forming the connection 20b, and the filter 20f can be integrated directly into the connection 20b, as can the cover 20b. This can save considerable space and effort.
• the amount of air flowing through the separation space 20 can be influenced via the throttle point 20i provided in the line 20h.
• the throttle point 20i can, for example, be integrated into the connection 20a by appropriate dimensioning of the bore forming the connection 20a, or the throttle point 20i can be obtained in the desired manner by appropriately small dimensions of the inner cross section of the line 20h.
• the amount of air flowing through the separation space 20 and the pressure in the separation space 20 can be influenced. If the throttle point 20g provided upstream in front of the separation space 20 is of relatively small dimensions, ie the throttle point 20g has a relatively small inner diameter, and in comparison the throttle point 20i provided downstream of the separation space 20 is dimensioned relatively large, so there is a relatively low pressure (ie a relatively strong negative pressure) in the separating space 20, which can possibly be almost as low as the negative pressure in the intake manifold 30c. It can thereby be achieved that the fuel leaking from the fuel space 16 (FIG.
• the line 20h leads between the air filter 30b and the throttle valve 30d into the intake manifold 30c.
• the exemplary embodiment shown can also be modified such that the line 20h opens into the intake manifold 30c between the throttle valve 30d and the combustion chambers of the internal combustion engine 24.
• the pressure in the separation space 20 is then quite heavily dependent on the position of the throttle valve 30d, and air enters the air inlet 30 even when the throttle valve 30d is completely closed, which is not desirable for all internal combustion engines.
• FIG. 3 shows a likewise schematic representation of a further exemplary embodiment.
• the cover 20c shown in FIG. 2, the opening 20d, the line 20e, the filter sieve 20f, the throttle point 20g and the opening into the separation space 20 are omitted second connection 20b.
• the separation space 20 is connected to the air inlet 30 only via the connection 20a, via the line 20h and via the more or less throttling throttle point 20i. Small internal diameters are sufficient for the connection 20a and the line 20h. This results in the throttle point 20i of its own accord. In principle, the throttle point 20i can be dispensed with.
• Throttle valve 30d receives unwanted air.
• connection of the separation space 20 with the air inlet 30 gives the advantage that the fuel which may leak from the fuel space 16 into the separation space 20 cannot escape into the environment, but instead reaches the internal combustion engine 24, where it can be properly burned.
• FIG. 4 shows, in schematic form, a further, preferably selected, particularly advantageous exemplary embodiment.
• the internal combustion engine 24 there are moving parts. To lubricate these parts, the internal combustion engine 24 has an internal combustion engine lubrication 32 and an oil pump 32a. Basically all internal combustion engines in question have internal combustion engine lubrication. An oil pump is always part of the internal combustion engine lubrication system.
• the separation chamber 20 is connected to the internal combustion engine lubrication 32. This is at the
• a first oil connection 20k and a second oil connection 20m are provided.
• the first oil connection 20k is connected to the connection 20b via an oil line 20n.
• An oil line 20p connects the connection 20a to the second oil connection 20m.
• a throttle point 20r In the course of the oil line 20n there is a throttle point 20r.
• oil pump 32a of the internal combustion engine lubrication 32 promotes the oil through the internal combustion engine 24 to the lubrication points provided in the internal combustion engine 24.
• the oil also reaches the oil connection 20k. From the oil connection 20k, the oil flows through the oil line 20n, through the throttle point 20r, through the connection 20b, through the separation space 20, through the connection 20a and through the oil line 20p back into the internal combustion engine 24 to the internal combustion engine lubrication 32. Is the pressure of the oil at the oil connection 20k is relatively high, then the
• Throttle point 20r can be dimensioned relatively small so that the pressure of the oil in the separation space 20 is not too high.
• the oil connection 20k is located at a point in the internal combustion engine lubrication 32 at which the oil in the internal combustion engine lubrication 32 is not too high Has pressure, then the throttle point 20r can be dispensed with.
• the throttle position 20r can also be achieved, for example, by appropriately small dimensions of the inside diameter of the oil lines 20n and 20p or by appropriately small dimensions of the connections 20a, 20b.
• the separation space 20 can be connected to the main flow or to the internal combustion engine lubrication 32 via a bypass.
• Separation chamber 20 leaking fuel is so small that there is no fear of any negative effects on the properties of the oil of the internal combustion engine lubrication 32.
• the bearing seal 14c could not always reliably prevent fuel from getting into the area of the bearing 14. This could damage the bearing 14 or parts of the bearing 14 and shorten the durability of the bearing 14. In particular, the bearing seal 14c could also be damaged by the fuel without the chamber 20. All of this is prevented by the separating space 20 and by the separating means provided in the separating space 20.
• the Release agent which is preferably air (Fig. 2, 3) or oil (Fig.
• the seal 18 and the bearing seals 14c and 14d can advantageously be optimized for cost-effective production and for low friction between the shaft 12a and the housing 4. Without the separating space 20, there would be the danger that fuel could get to the outside via the bearing seal 14c into the area of the bearing 14 and via the bearing seal 14d between the shaft 12a and the housing 4. This is also reliably prevented in a simple manner by the separating space 20.
• the shaft 12a is supported on one side. It is proposed that the shaft be supported on both sides, ie. H. if the shaft 12a is supported on both sides of the fuel chamber 16 via a respective bearing, a separating space must be provided between the fuel chamber 16 and each of the two bearings. In both
• Separation rooms are preferably air or oil as a release agent.
• the two separation spaces can be connected to one another inside or outside the housing of the fuel pump 2.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Fuel-Injection Apparatus (AREA)
• Details Of Reciprocating Pumps (AREA)

Applications Claiming Priority (3)

Publications (1)

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ID=7799418

Family Applications (1)

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• 1996
  • 1996-07-10 DE DE19627757A patent/DE19627757A1/de not_active Withdrawn
• 1997
  • 1997-04-18 EP EP97921619A patent/EP0850359A1/de not_active Withdrawn
  • 1997-04-18 WO PCT/DE1997/000777 patent/WO1998001673A1/de not_active Application Discontinuation
  • 1997-04-18 RU RU98107145/06A patent/RU2185523C2/ru active
  • 1997-04-18 US US09/029,973 patent/US5967123A/en not_active Expired - Lifetime
  • 1997-04-18 KR KR1019980701755A patent/KR19990044507A/ko not_active Application Discontinuation
  • 1997-04-18 JP JP10504626A patent/JPH11514716A/ja active Pending

Non-Patent Citations (1)

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