EP2872771A1

EP2872771A1 - High-pressure pump

Info

Publication number: EP2872771A1
Application number: EP13733272.2A
Authority: EP
Inventors: Achim Koehler; Armin Merz; Sandro Soccol; Joerg Morlok
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2012-07-11
Filing date: 2013-06-27
Publication date: 2015-05-20
Anticipated expiration: 2033-06-27
Also published as: DE102012212153A1; EP2872771B1; CN104487699A; WO2014009164A1; CN104487699B; IN2014DN10747A

Abstract

The invention relates to a high-pressure pump (1) for pumping a fluid, in particular fuel, for example diesel, comprising a housing (8); a driveshaft (2) with at least one cam (3); at least one piston (5); at least one cylinder (6) for bearing the at least one piston (5), said at least one piston (5) being supported indirectly on the driveshaft (2) with the at least one cam (3) such that a translational movement can be carried out by the at least one piston (5) on the basis of a rotational movement of the driveshaft (2); a lubricating chamber (40), within which the driveshaft (2) with the at least one cam (3) is arranged, for lubricating and cooling the driveshaft (2); and at least one shaft sliding bearing for bearing the driveshaft, wherein a fluidic connection is provided from a gap, in particular an annular gap, between the shaft sliding bearing and the driveshaft (2) to the lubricating chamber (40) such that the at least one shaft sliding bearing is lubricated and cooled by the lubricating fluid from the lubricating chamber (40). At least one channel is introduced into the housing (8) and/or a bearing bush (41) for the driveshaft (2) in order to additionally discharge lubricating fluid out of the lubricating chamber (40).

Description

Description title

high pressure pump

The present invention relates to a high-pressure pump according to the preamble of claim 1 and a high-pressure injection system according to the preamble of claim 10.

State of the art

In high-pressure injection systems for internal combustion engines, especially in common-rail injection systems of diesel or gasoline engines, a high-pressure pump permanently ensures the maintenance of the pressure in the

High pressure accumulator of the common rail injection system. The high-pressure pump can be driven, for example, by a camshaft of the internal combustion engine by means of a drive shaft. For the promotion of the fuel to the high-pressure pump Vorförderpumpen, z. B. a gear or

Rotary vane pump, used, which are upstream of the high-pressure pump. The prefeed pump delivers the fuel from a fuel tank through a fuel line to the high pressure pump.

Amongst others, piston pumps are used as high-pressure pumps. In a housing, a drive shaft is mounted. Radially to pistons are arranged in a cylinder. On the drive shaft with at least one cam is a roller with a roller rolling surface, which is mounted in a roller shoe. The roller shoe is connected to the piston, so that the piston is forced to oscillate translational motion. A spring applies to the roller shoe a radially directed to the drive shaft force, so that the roller is in constant contact with the drive shaft. The roller is available the roller rolling surface on a shaft rolling surface as the surface of the drive shaft with the at least one cam in contact with the drive shaft. The roller is mounted by means of a sliding bearing in the roller shoe.

The high-pressure pump has a lubricant space formed within a housing and within the lubricant space the drive shaft with the cams, the roller shoe and the roller is arranged. The lubricating space is traversed by fuel as a lubricating fluid for lubrication and cooling of the components, d. H. in particular the roller, the roller shoe and the drive shaft as well as the piston, which is slidably mounted on a piston guide on the housing. The funded by the feed pump fuel is thereby part of the high-pressure pump, d. H. one

Intake passage, the high-pressure pump supplied and another part of the pumped by the feed pump fuel is passed through the lubricating space for cooling and lubrication of the components within the lubricating space. The housing includes an opening for passage and sliding bearing of

Drive shaft and a blind hole for mounting the drive shaft. The drive shaft is slidably mounted on the blind hole and the opening by means of a bearing bush. There is a gap between the drive shaft and the two bearing bushes, in particular an annular gap through which the fuel flows for lubrication and cooling of the shaft plain bearing on the bearing bush. This fuel, which due to the clearance between the drive shaft and the bearing bush axially flows through this gap or gap, in particular annular gap, is thereby after flowing through a

Fuel return line fed back to the fuel tank. Due to a different bearing clearance also occurs a different volume flow of fuel through the two shaft plain bearings. This one by the two

However, fuel flowing away from the shaft space in the lubricant space does not suffice for sufficient cooling of the components within the lubricant space. For this reason, the housing is provided with an additional cooling throttle for the additional discharge of fuel from the lubricating space. This cooling throttle disadvantageously requires additional components and thus increases the manufacturing cost of the high-pressure pump. DE 10 2006 045 933 A1 shows a high pressure pump for high pressure fuel delivery. The high-pressure pump has a drive shaft with cams. Cylindrical rollers are supported by roller shoes and rest on the cams. The roller shoes are mounted by means of a plunger assembly in a bore of a part of the housing. The pump elements are at the

Tappet assembly attached. A coil spring presses the plunger assembly onto the cams.

From DE 103 56 262 A1 is a radial piston pump for

High-pressure fuel production in fuel injection systems of

Internal combustion engines known. In a pump housing, a drive shaft is mounted. Pistons are supported on the drive shaft, so that by rotating the drive shaft, the pistons are moved back and forth. Between the piston and the drive shaft tappets are arranged.

Disclosure of the invention

Advantages of the invention

Inventive high-pressure pump for conveying a fluid, in particular fuel, for. B. diesel, comprising a housing, a drive shaft with at least one cam, at least one piston, at least one cylinder for supporting the at least one piston, wherein the at least one piston indirectly, in particular by means of at least one roller or a bucket tappet, on the drive shaft the at least one cam is supported, so that from the at least one piston a translational movement due to a rotational movement of the drive shaft is executable, a lubricating space within which the drive shaft is arranged with the at least one cam, for lubrication and cooling of the drive shaft, at least one shaft sliding bearing for storage the drive shaft with a fluid-conducting

Connection of a gap, in particular annular gap, between the

Shaft bearing and the drive shaft to the lubricating space, so that the at least one shaft sliding bearing with the lubricating fluid from the

Lubrication chamber is lubricated and cooled, wherein in the housing and / or a bearing bush for the drive shaft at least one channel is incorporated for the additional discharge of lubricating fluid from the lubricant space. In the housing and / or the bearing bush for the drive shaft at least one channel is incorporated, thereby additionally in addition to the gap, in particular annular gap, due to a game between the drive shaft and the journal bearings fuel can be derived from the lubricating space in order to perform a sufficient cooling of the components within the lubricating space can. As a result, no additional or additional cooling throttle is required as a separate component on the high pressure pump on the lubricating space in an advantageous manner. Conveniently, an opening in the housing, which is exclusively bounded by the housing, is not considered to be the channel.

Expediently, the high-pressure pump does not comprise a cooling throttle as a separate component and, in particular, exclusively for this purpose. With the at least one channel can thus be additionally derived with existing components of the fuel from the lubricating space by the channel is incorporated into the housing and / or the bearing bush and thus no additional components are required.

In particular, the at least one channel is formed as a groove in the housing and / or the bearing bush and / or the housing has a

Opening and / or a blind hole for storage of the drive shaft and the at least one channel is formed on the opening and / or the blind hole and / or the housing comprises a hull housing and a bearing cover housing. Suitably, the at least one channel in the housing and / or the

Bearing bush incorporated by embossing and / or milling and / or by means of a laser. As a result, no additional components for the additional discharge of lubricating fluid from the lubricating space are required in an advantageous manner, because the at least one channel can be integrated into existing components. Preferably, the at least one groove is formed on a radial outer side of the bearing bush.

In a further embodiment, the groove is V-shaped in cross-section,

rectangular or circular segment-shaped.

In a supplementary embodiment, the at least one channel opens into a return bore and / or a return line. The derived by the at least one channel lubricating fluid, in particular fuel, is after deriving from the channel through the return line and / or the

Return bore fed back to a fuel tank.

Preferably, the at least one incorporated into the housing channel of the housing and the bearing bush is limited, since the at least one in the

Housing incorporated channel is incorporated in the region of a bearing surface of the bearing bush on the housing. The at least one channel is thus formed between the housing and the bearing bush. In a variant, the at least one channel of the shaft sliding bearing and the

Limited drive shaft, since the at least one channel in the shaft sliding bearing, in particular in the housing or the bearing bush, is incorporated. The at least one channel is thus between the shaft sliding bearing and the

Drive shaft formed. The shaft sliding bearing is formed for example by the housing or the bearing bush.

The high-pressure pump expediently comprises at least two or three channels, in particular per shaft sliding bearing for the drive shaft, and / or at least one channel opens into an annular channel and preferably the annular channel opens into a return bore and / or a return line.

Suitably, the at least one channel is aligned parallel or at an acute angle to a rotational axis of the drive shaft. Preferably, the acute angle is between 1 ° and 45 °, in particular between 1 ° and 30 °.

In a further embodiment, the annular channel is incorporated in an analogous manner as the at least one channel in the housing and / or the bearing bush.

In particular, the gap, in particular annular gap, between the

Shaft bearing and the drive shaft by a return restrictor with the return bore and / or the return line in fluid-conducting

Connection and in particular the return restriction throttle in an analogous manner as the at least one channel is incorporated in the housing and / or the bearing bush. The return restriction restrictor serves to cause the leakage between the shaft sliding bearing and the drive shaft due to play

Fuel in the quantity is limited to one due to wear and / or Manufacturing tolerances occurring very large game to get a return flow limitation of the lubricating fluid from the lubricating space due to the gap between the shaft sliding bearing and the drive shaft. Suitably, the return restrictor is incorporated in an analogous manner as the at least one channel in the housing and / or bearing bush for the drive shaft, ie, for example, as a groove on a radial outer side of the bearing bush. When working the groove in the bearing bush so that both the channel and the return restriction throttle can be made and only by a different contact pressure during pressing grooves with a different flow cross-sectional area for the channel and the

Return limiting restrictor are produced.

A high-pressure injection system for an internal combustion engine according to the present invention, comprising a high-pressure pump having a lubrication space, a high-pressure rail, a demand pump for supplying a fuel from a fuel tank to the high-pressure pump, the high-pressure pump being one of them

Patent application described high-pressure pump is formed.

In a supplementary variant, the high-pressure injection system, in particular the high-pressure pump, comprises a pressure sensor for detecting the pressure in the lubricant space.

In a further variant, the delivery rate of the forecasting pump, in particular as a function of the pressure detected by the pressure sensor in the lubricant chamber and / or as a function of the volume flow of fuel required by the internal combustion engine, can be controlled and / or regulated. The delivery rate of the precharge pump is controlled and / or regulated to the effect that on the one hand there is sufficient fuel for the internal combustion engine, ie a sufficient volume flow of fuel is supplied to the inlet channel of the high-pressure pump and on the other hand enough fuel flows through the lubricant space for lubrication and / or cooling as the second Volume flow and this second volume flow is dependent on the pressure within the lubricating space. For this reason, a sufficient volume flow of fuel can be passed through the lubricant space with the pressure sensor for cooling and / or lubrication of the components within the lubricating space. In a further embodiment, the pre-demand pump is a pre-demand pump with electric motor, so that the pre-demand pump is driven by the electric motor and in particular the delivery rate of the pre-demand pump can be controlled and / or regulated.

The drive shaft with the at least one cam is expediently a drive shaft which is circular in cross-section and which is mounted eccentrically to a central longitudinal axis of the drive shaft so that the axis of rotation is at a distance from the longitudinal axis. The longitudinal axis is arranged in cross section in the center of the circular drive shaft.

Suitably, the Vorforderpumpe is a gear or rotary vane pump.

Brief description of the drawings

Hereinafter, embodiments of the invention below

With reference to the accompanying drawings described in more detail. It shows:

1 shows a cross section of a high-pressure pump for conveying a fluid,

2 shows a section A-A of FIG. 1 a roller with roller shoe and a drive shaft,

3 is a highly schematic view of a high-pressure injection system,

Fig. 4 is a greatly simplified cross-section of the high pressure pump

a demand pump,

5 shows a section of the housing of the high-pressure pump with an opening and a blind hole for mounting the drive shaft,

Fig. 6 is a longitudinal section of a sliding bearing at the opening with

a bushing,

Fig. 7 is a longitudinal section of the sliding bearing on the blind hole with the bearing bush,

8 shows a first embodiment of the at least one channel,

9 shows a second embodiment of the at least one channel,

10 shows a third embodiment of the at least one channel,

1 1 shows a fourth embodiment of the at least one channel,

12 shows a fifth embodiment of the at least one channel,

13 is a sixth embodiment of the at least one channel,

Fig. 14 shows a first embodiment of the at least one channel

with a ring channel,

Fig. 15 shows a second embodiment of the at least one channel

with a ring channel,

16 shows a partial cross section of the bearing bush with a cross section

V-shaped channel,

17 shows the partial cross section of the bearing bush with a cross section

rectangular channel,

Fig. 18 is a partial cross section of the bearing bush with a cross-section

circular segmented channel,

Embodiments of the invention

In Fig. 1 is a cross section of a high-pressure pump 1 for conveying fuel is shown. The high-pressure pump 1 serves to fuel, z. As gasoline or diesel, to an internal combustion engine 39 for a motor vehicle (not shown) to promote under high pressure. The pressure which can be generated by the high-pressure pump 1 is, for example, in a range between 1000 and 3000 bar.

The high-pressure pump 1 has a drive shaft 2 with two cams 3, which performs a rotational movement about a rotation axis 26. The rotation axis

26 lies in the drawing plane of Fig. 1 and is perpendicular to the

2. A piston 5 is mounted in a cylinder 6 which is formed by a housing 8 of the high-pressure pump 1. A high pressure working chamber 29 is bounded by the cylinder 6 as a piston guide 7, the housing 8 and the piston 5. Into the high-pressure working space 29 opens an inlet channel 22 with an inlet valve 19 and an outlet channel 24 with an outlet valve 20. Through the inlet channel 22 with an inlet opening 21, the fuel flows into the high-pressure working chamber 29 and through the outlet channel 24 with an outlet opening 23, the fuel flows under High pressure from the

High-pressure workroom 29 Again off. The inlet valve 19, z. B. a

Check valve is designed so that only fuel in the

Working space 29 can flow and the exhaust valve 20, z. B. a

Check valve is designed so that only fuel can flow out of the working chamber 29. The volume of the high-pressure working chamber 29 is changed due to an oscillating stroke movement of the piston 5. Of the

Piston 5 is indirectly supported on the drive shaft 2 from. At the end of the piston 5 or pump piston 5, a roller shoe 9 is attached to a roller 10. The roller 10 can perform a rotational movement, the

Rotation axis 25 lies in the plane of FIG. 1 and is perpendicular to the plane of Fig. 2. The drive shaft 2 with the at least one

Cam 3 has a shaft rolling surface 4 and the roller 10 has a roller rolling surface 1 1.

The roller tread 1 1 of the roller 10 rolls on the shaft rolling surface 4 as a contact surface 12 of the drive shaft 2 with the two cams 3 from. Of the

Roller shoe 9 is mounted in a roller shoe bearing formed by the housing 8 as a sliding bearing. A spring 27 or coil spring 27 as an elastic element 28 which is clamped between the housing 8 and the roller shoe 9, brings on the roller shoe 9 a compressive force, so that the roller rolling surface 1 1 of the roller 10 in constant contact with the waves Rolling surface 4 of the drive shaft 2 is. The roller shoe 9 and the piston 5 lead with it together an oscillating stroke movement. The roller 10 is mounted with a sliding bearing 13 in the roller shoe 9.

In Fig. 3 is a highly schematic representation of a high-pressure injection system 36 for the motor vehicle shown with a high-pressure rail 30 or a

Fuel rail 31. From the high-pressure rail 30 and a

Fuel distribution pipe 31, the fuel is injected by means of valves (not shown) in the combustion chamber of the internal combustion engine 39. An electric pre-demand pump 35 delivers fuel from a fuel tank 32 through a first fuel line 33a to the intake passage 22 and through a second fuel line 33b to a lubricating space 40 (FIG. 4)

High pressure pump 1. The high pressure pump 1 is driven by the drive shaft 2 and the drive shaft 2 is connected to a shaft, for. As a crankshaft or camshaft, the engine 39 is connected. The delivery rate of the electric pre-charging pump 35 is controllable and / or controllable, so that thereby the amount of fuel delivered to the inlet channel 22 per

Time unit can be controlled and / or regulated. The high-pressure rail 30 serves to inject the fuel into the combustion chamber of the internal combustion engine 39. The fuel which is not required by the high-pressure pump 1 is thereby returned to the system through an optional fuel return line 34

Fuel tank 32 returned.

Fig. 4 shows a part of the high-pressure injection system 36. Within the

Housing 8 of the high pressure pump 1, the lubricating space 40 is formed. In the lubricating space 40 are the drive shaft 2, the roller 10, the roller shoe. 9

(Not shown in Fig. 4) and partially the piston 5 is arranged. By means of the fuel passed through the lubricant space 40, these components 2, 5, 9 and 10 are lubricated by the fuel. The introduced through the second fuel line 33 b in the lubricating chamber 40 is fuel through the

Fuel return line 34 from the lubricating chamber 40 discharged the

Fuel tank 32 fed back (Figure 4). In FIG. 4, the high pressure injection system 36 shown in FIG. 3 is shown in more detail without the high pressure rail 30 and without the engine 39. The sucked by the Vorforderpumpe 35 from the fuel tank 32 fuel is supplied by the Vorforderpumpe 35 with a prefeed, z. B. 4 bar, through the first fuel line 33 a the

Inlet passage 22 of the high pressure pump 1 is supplied. Furthermore, the of the Pre-feed pump 35 pumped fuel during operation of the

Internal combustion engine 39 through the second fuel line 33b to the lubricating space 40 supplied to the lubrication, z. B. the drive shaft 2, the roller 10 and the piston 5. After flowing through the fuel through the lubricating chamber 40, the fuel is again through the fuel return line 34 to the fuel tank

32 supplied. As a result, these components 2, 5, 9 and 10 can be lubricated as well as cooled. The prefeed pump 35 thereby promotes in addition to the flow rate for the high-pressure pump 1 of fuel and an additional amount of fuel for lubrication of the high-pressure pump 1, d. H. of the fuel flowing through the lubricating space 40.

The electric prefeed pump 35 has an electric motor 17 and a

Rotary piston pump 16, namely a gear pump 14, d. H. a

Internal gear pump 15 and gerotor pump 15 (FIG. 4). The

High-pressure pump 1 delivers fuel under high pressure, for example one

Pressure of 1000, 3000 or 4000 bar, through a high-pressure fuel line to a high-pressure rail 31st From the high-pressure rail 31, the fuel is supplied under high pressure from an injector to a combustion chamber (not shown) of the internal combustion engine 39. The electric motor 17 of the electric

Pre-feed pump 35 is operated with three-phase or alternating current and is controllable in performance and / or adjustable. The three-phase current or alternating current for the electric motor 17 is provided by a power electronics, not shown, from a DC voltage network of a vehicle electrical system of a motor vehicle (not shown). The electric prefeed pump 35 is thus an electronically commutated prefeed pump 35.

The housing 8 of the high-pressure pump 1 is subdivided into a hull housing 46 and into a bearing cover housing 47 as separate components (FIGS. 4 and 5). The hull housing 46 is formed with a blind hole 45 and the

Bearing housing 47 or flange housing 47 has an opening 44

(Figures 5 to 7). The opening 44 serves to form a shaft sliding bearing 18 for the drive shaft 2 and also for the implementation of the drive shaft 2 outside the lubricating space 40, so that thereby the drive shaft 2 can be mechanically connected, for example, with a camshaft, not shown, of the engine 39. The blind hole 45 only serves to provide a shaft sliding bearing 18 for the drive shaft 2 available. Both in the blind hole 45 and in the opening 44, a bearing bush 41 by means of a press fit on a bearing surface 49 on the housing 8, ie the hull housing 46 and the bearing cap housing 47, on or pressed. The bearing bush 41 thus forms on its radial inside the shaft sliding bearing 18 on which the drive shaft 2 rests.

There is a clearance between the drive shaft 2 and the two shaft plain bearings 18 on the two bearing bushes 41 at the opening 44 and the blind hole 45, thereby forming a gap 37, in particular an annular gap 38 between the drive shaft 2 and the bearing bush 41. Through this

Gap 37 flows under a pressure of, for example, 4 to 5 bar standing fuel within the lubricant chamber 40 in the axial direction to an axial end of the shaft sliding bearing 18. At the blind hole 45 of the fuselage housing 46 as part of the housing 8, a drain hole 52 is also present. The fuel flowing through the gap 37 between the drive shaft 2 and the bearing bush 41 is thus collected at the drainage bore 52 and then fed back to the fuel tank 32 through the fuel return line 34 shown in FIG. At the opening 44 (Fig. 6), a shaft seal, not shown, is present and further sealing means, for. B.

Sealing rings, so that thereby from the annular gap 38 between the

Drive shaft 2 and the bearing bush 41 at the opening 44 effluent fuel can be collected and by a

Return restrictor 51 collected a return bore 48 is supplied. To the return bore 48 is in an analogous manner as at

Outflow bore 52, the fuel return line 34 connected. The

Return limitation throttle 51 has a predetermined

Flow cross-sectional area, so that with an increase of the game and thus an enlargement of the gap 37, for example due to

Wear, the derivative of fuel through the gap 37 is limited. In an analogous manner, the drainage hole 52 is as a

Return limitation throttle 51 is formed. After flowing through the return restriction throttle 51 between the bearing bush 41 and the

Bearing housing 47, this fuel of the return bore 48 is supplied due to a corresponding fluid-conducting connection and the incorporated in the bearing cap housing 47 return bore 48 is fluidly connected to the fuel return line 34. In the bearing bush 41, a groove 43 (Fig. 6) is incorporated on the radially outer side by means of embossing, pressing or milling. The bearing bush 41 is fixed by means of a press fit to the opening 44 of the bearing cap housing 47, ie on the support surface 49. The rotational position of the bearing bush 41 with respect to

Bearing housing 47 is fixed, so that on the one hand due to the groove 43, a channel 42 between the bearing cap housing 47 and the bearing bush 41 is formed and this channel 42 and hydraulically with the

Return bore 48 is connected, since the channel 42 due to the orientation of the bearing bush 41 with respect to the bearing cap housing 47 in the

Return bore 48 opens. Thus open into the return bore 48, both the channel 42 and the return restriction throttle 51. Die

Return restrictor 51 is similar to the channel 42 in the radial outer side of the bearing bush 41 by means of pressing or embossing

incorporated. The fuel flowing out through the channel 42 is thus also supplied to the fuel return line 34 through the return bore 48.

In an analogous manner, the bearing book 41 on the blind hole 45 also on the outside a groove 43 (Fig. 7) and thereby forms between the bearing bush 41 and the body shell 46 also the channel 42. Through this channel 42 can be additionally derived fuel, which through the drain hole 52 also the fuel return line 34 and thus the fuel tank 32 is supplied. The flow cross-sectional area of the drainage bore 52 may optionally also be designed such that the drainage bore 52 also serves as a return restriction throttle 51.

The fuel delivered by the prefeed pump 35 is supplied on the one hand through the first fuel line 33a to the inlet channel 22 and through the second fuel line 33b the lubricating chamber 40. The lubricating chamber 40 is completely filled with fuel and the fuel is used for lubrication

Components, e.g. B. the drive shaft 2 and the roller shoe 9, and also for cooling these components. In order to ensure sufficient cooling of these components, a sufficient volume flow of fuel must be passed through the lubricating space 40. The flowing through the gap 37 fuel between the drive shaft 2 and the bearing bush 41 due to a clearance between the bearing bush 41 and the drive shaft. 2 Outflowing fuel is not sufficient in its volume flow for cooling the lubricating space 40. For this reason, by the two channels 42, which are incorporated on the radial outer side of the two bushings 41 in the form of grooves 43, in addition fuel from the

Lubrication chamber 40 are derived. In this case, this channel 42 is a cooling throttle without additional components to the high-pressure pump 1, because the channel 42 is integrated into existing components, namely by the groove 43 is incorporated into the bearing bush 41 on the outside. In Figs. 8 to 13 are views of the bearing bush 41 in different

Embodiments for the channels 42 are shown. In Fig. 8, the

Bearing bush 41 only a channel 42 and a groove 43 which is aligned parallel to a rotation axis 26 of the drive shaft 2. In the embodiment shown in Fig. 9, the bearing bush 41 has two grooves 43 and in the embodiment shown in Fig. 10, the grooves 43 are incorporated at an acute angle to the axis of rotation 26. The embodiment shown in Fig. 1 1 differs from the embodiment shown in Fig. 10 in that the two grooves 43 are interconnected by an additional groove and in Fig. 12, the two grooves 43 are also connected to each other by an additional groove, but parallel to the

Rotation axis 26 aligned. In that shown in Fig. 13

Embodiment open two grooves 43 in the lubricating space 40 and these two grooves 43 then open into only one groove 43. In FIGS. 14 and 15 are two embodiments of the embodiment of

Bearing bush 41 in addition to at least one groove 43 also shown in addition to an annular channel 50. The embodiment shown in Fig. 14 corresponds to the embodiment shown in Fig. 8 and differs only in that an annular channel 50 is present. In an analogous way

The embodiment illustrated in FIG. 15 differs from that in FIG

Fig. 9 illustrated embodiment only in that an annular channel 50 is present. In an analogous manner, the exemplary embodiments illustrated in FIGS. 10 to 13 can also be provided with an annular channel 50. At a

Ring channel 50 is the bearing bush 41 in the opening 44 is not in his

Align the angular position with respect to the return bore to the effect that the channel 42 opens directly into the return bore 48. At a Ring channel 50 does not have the bearing bush 41 corresponding in its

Rotational angular position to be aligned with the bearing cap housing 48, but only the axial alignment of the bearing bush 41 must be made to the effect that the annular channel 50 opens into the return bore 48.

The cross-sectional shape of the groove 43 incorporated in the bearing bushing 41 is arbitrary and may, for example, be V-shaped (FIG. 16), rectangular (FIG. 17) or circular segment-shaped (FIG. 18).

In a further, not shown embodiment, the groove 43 is not on the radial outer side of the bearing bush 41, but on the radial inner side of the bearing bush 41, d. H. formed on the shaft sliding bearing 48. The channel 42 is thereby bounded by the bearing bush 41 or the shaft sliding bearing 18 and the drive shaft 2. This can additionally fuel from the

Lubrication chamber 40 are derived.

In a further embodiment, not shown, the return flow restrictor 51 and the return bore 48 are formed at the blind hole 45 as in the embodiment in Fig. 6 at the opening 44 and the housing 8, d. H. the hull housing 46 has no drainage bore 52 on the blind hole 45.

In the lubricating space 40, a pressure sensor 53 is present. The pressure sensor 53 detects the pressure of the fuel within the lubricating space 40, which is for example in the range of 4 to 5 bar. The delivery rate of

Pre-feed pump 35 is controllable and / or regulated and is thereby controlled and / or regulated so that in the lubricating chamber 40, a constant pressure of 4 to 5 bar is present. In this case, the pressure in the lubricating space 40 can also be increased in order to discharge an increased amount of fuel from the lubricating space 40 by increasing the pressure in order to increase the pressure

Cooling power with the guided through the lubricating chamber 40 volume flow of fuel and vice versa.

Overall, significant advantages are associated with the high-pressure pump 1 according to the invention. The high-pressure pump 1 does not have a separate cooling throttle for the additional discharge of fuel from the lubricating space 40 on, so that thereby the manufacturing cost of the high-pressure pump 1 can be lowered. In already existing components of the high-pressure pump 1, namely the bearing bush 41, a groove 43 is incorporated, thereby forming a channel 42 as a cooling throttle for the additional discharge of fuel from the lubricating space 40.

Claims

claims

1 . High-pressure pump (1) for conveying a fluid, in particular fuel, for. As diesel, comprising

a housing (8),

a drive shaft (2) with at least one cam (3),

at least one piston (5),

at least one cylinder (6) for supporting the at least one piston (5),

- wherein the at least one piston (5) indirectly on the

Drive shaft (2) with the at least one cam (3) is supported, so that of the at least one piston (5) a

Translational movement due to a rotational movement of the drive shaft (2) is executable,

- A lubricating space (40), within which the drive shaft (2) with the at least one cam (3) is arranged, for Schmierrung and cooling of the drive shaft (2),

- At least one shaft sliding bearing (18) for supporting the drive shaft (2) with a fluid-conducting connection of a gap (37), in particular annular gap (38), between the shaft sliding bearing (18) and the drive shaft (2) to the lubricating space (40), so in that the at least one shaft sliding bearing (18) is lubricated and cooled with the lubricating fluid from the lubricating space (40), characterized in that at least one channel (8) and / or a bearing bush (41) for the drive shaft (2) 42) is incorporated for the additional discharge of lubricating fluid from the lubricating space (40).

2. High-pressure pump according to claim 1, characterized in that the at least one channel (42) is formed as a groove (43) in the housing (8) and / or the bearing bush (41)

and or

the housing (8) has an opening (44) and / or a blind hole (45) for mounting the drive shaft (2) and the at least one channel (42) is formed on the opening (44) and / or the blind hole (45)

and or

the housing (8) comprises a body shell (46) and a bearing cap housing (47).

3. High-pressure pump according to claim 2, characterized in that the groove (43) in cross-section V-shaped, rectangular or

is formed circular segment.

4. High pressure pump according to one or more of the preceding

Claims, characterized in that the at least one channel (42) in a return bore (48) and / or a return line (34) opens.

5. High pressure pump according to one or more of the preceding

Claims, characterized in that the at least one channel (42) incorporated in the housing (8) is delimited by the housing (8) and the bearing bush (41), since the at least one channel (42) incorporated in the housing (8) in the region of a contact surface (49) of the bearing bush (41) on the housing (8) is incorporated.

6. High pressure pump according to one or more of the preceding

Claims, characterized in that the at least one channel (42) of the shaft sliding bearing (18) and the drive shaft (2) is limited, since the at least one channel (42) in the shaft sliding bearing (18), in particular in the housing (8). or the

Bushing (41) is incorporated.

7. High-pressure pump according to one or more of the preceding

Claims, characterized in that the high-pressure pump (1) comprises at least two or three channels (42), in particular each shaft sliding bearing (18) for the drive shaft (2), and / or

at least one channel (42) opens into an annular channel (50)

and preferably

the annular channel (50) in a return bore (48) and / or a

Return line (34) opens.

8. High-pressure pump according to claim 7, characterized in that the annular channel (50) in an analogous manner as the at least one channel (42) in the housing (8) and / or the bearing bush (41) is incorporated.

9. High pressure pump according to one or more of the preceding

Claims, characterized in that the gap (37), in particular annular gap (38), between the

Shaft bearing (18) and the drive shaft (2) by a

Return restrictor (51) with the return bore (48) and / or the return line (34) is in fluid communication

and particularly

the return restriction throttle (51) is incorporated in an analogous manner as the at least one channel (42) in the housing (8) and / or the bearing bush (41).

10. High-pressure injection system (36) for an internal combustion engine (39),

full

a high-pressure pump (1) having a lubricating space (40),

a high pressure rail (30),

- A prefeed pump (35) for conveying a fuel from a fuel tank (32) to the high pressure pump (1), characterized in that the high pressure pump (1) is designed as a high pressure pump (1) according to one or more of the preceding claims.

1 1. High-pressure injection system according to claim 10, characterized in that the high-pressure injection system (36), in particular the high-pressure pump (1), a pressure sensor (53) for detecting the pressure in the

Includes lubricating space (40).

12. High-pressure injection system according to claim 10 or 1 1, characterized in that the delivery rate of the prefeed pump (35), in particular in

Dependence on that of the pressure sensor (53) in the lubricating space (40) detected pressure and / or in dependence on the of the internal combustion engine (39) required volume flow of fuel, controllable and / or regulated.