DE102013218257A1 - High pressure pump with integrated coolant and / or lubricant supply - Google Patents

Abstract

A high-pressure pump (1) with an integrated coolant and / or lubricant supply comprises a pump piston (10), a tappet (20) for moving the pump piston (10), a tappet guide (30) for guiding the tappet (20) and a roller (40) ) to rest on a drive shaft (2). The tappet guide (30) is designed as a hollow body with a cavity, the tappet (20) being guided in the cavity and a gap between an inner wall (I30) of the tappet guide (30) facing the cavity and the tappet (20) (S) is formed. The tappet guide (30) has at least one channel (31a, 31b, 32) for supplying the coolant and / or lubricant (3) to the roller (40) and / or the gap (S).

Description

The invention relates to a high-pressure pump with integrated coolant and / or lubricant supply.

In a common rail injection system, the injection pressure can be generated independently of the engine speed and the injection quantity. The decoupling of pressure generation and injection takes place through a pressure accumulator (rail). To generate pressure, a high pressure pump (HDP) is provided, which promotes the fuel in the pressure accumulator. The robustness of the drive elements of such a high pressure pump is highly dependent on the loads introduced, the tribological conditions and the temperature of the moving and in contact parts. The introduced loads, which are dependent on the injection pressure of the internal combustion engine and thus of the pump delivery pressure, can not be influenced or only with great effort. With increasing demands on the injection pressure, there is thus a need to optimize the tribological and thermal conditions by cooling and lubrication to ensure or increase the durability and reliability of the high pressure pump.

The high-pressure pump has in its interior a pump piston which is displaceably guided in a bore and defines a pump working space with one end face. The pump working chamber is connected via a fuel inlet channel with a fuel inlet, for example a feed pump. Furthermore, the pump working space is connected to a fuel discharge channel which forms a connection between the high-pressure pump and the pressure accumulator.

The pump piston is supported via a plunger on a cam of a drive shaft. The plunger is slidably mounted in a tappet guide of the high-pressure pump. Between the plunger and the cam of the drive shaft, a roller is provided, which rests on a cam surface. A rotational movement of the drive shaft or the cam on the drive shaft is translated via the roller and the plunger in a stroke movement of the pump piston. During operation of the high-pressure pump, most of the heat is emitted via the roller axis and the roller-cam contact surface. The roller axis and the contact surface roller cams are also those points that are dependent on the highest possible lubricant supply due to the rolling contact. In addition, there is friction or heat in a gap between the plunger and the plunger guide.

The object of the present invention is to provide a high pressure pump with integrated coolant and / or lubricant supply, by which it is possible to bring targeted amounts of coolant or lubricant in the tribologically and thermally differently stressed contact points on the drive of the high-pressure pump and thereby the To ensure robustness of the high pressure pump or increase.

An embodiment of a high-pressure pump with integrated coolant and / or lubricant supply is specified in claim 1. According to a possible embodiment, the high-pressure pump with integrated coolant and / or lubricant supply comprises a pump piston, a plunger for moving the pump piston and a plunger guide for guiding the plunger. The plunger guide is formed as a hollow body with a cavity, wherein the plunger is guided in the cavity and wherein between a cavity facing the inner wall of the plunger guide and the plunger, a gap is formed. The high pressure pump further includes a roller for supporting on a drive shaft, wherein the roller is disposed at one end of the plunger guide in the interior of the cavity and coupled to the plunger. The tappet guide has at least one channel for supplying the coolant and / or lubricant to the roller and / or the gap.

By the specified high-pressure pump, it is possible to use for cooling and lubrication of the drive elements, in particular the role and / or guided in the tappet guide plunger coolants or lubricants of an internal combustion engine and to lubrication and cooling intensive areas of the high pressure pump or the drive of the high pressure pump to lead. A sealed annular channel formed by the housing of the tappet guide and a pump installation bore offers the possibility of accommodating coolants and / or lubricants, for example engine oil, from a transverse bore in the engine block and distributing them variably via the at least one channel in the pump housing or in the housing of the tappet guide , The at least one channel in the housing of the tappet guide leads to the desired areas, in particular to the role and / or the gap between the tappet guide and the plunger.

With known available supply pressure, it is possible to influence the cooling and / or lubricating amount in the at least one channel via hydraulic throttling independently of each other. According to a further embodiment, the high-pressure pump has a nozzle for generating at least one of the at least one channel, preferably in a channel which leads from the annular channel to the roller Beam of coolant and / or lubricant in the direction of the role. By means of nozzles attached to the channel ends, the manner and the place of introduction of the coolant and / or lubricant can be influenced in a targeted manner.

According to a further embodiment, the high-pressure pump comprises a spray oil collector. For this purpose, for example, the tappet guide at one end, on which the roller is arranged, be shaped so that from the drive shaft in a rotation thrown off oil is collected by the spray oil collector. The geometric shape of the pump housing or the housing of the tappet guide can thus be kept or collected in the region of the drive elements of the pump coolant and / or lubricant.

The spray oil collector may be formed, for example, as an incision in the pump housing in the axial direction of the drive shaft. It may have a dripping edge tapered towards the center of the cam of the drive shaft. This makes it possible to collect the oil supplied from the at least one channel as well as the spray oil thrown off the cam in this area, thereby increasing the amount of coolant and / or lubricant introduced into the contact points of the high-pressure pump.

The invention will be explained in more detail below with reference to figures showing exemplary embodiments of the present invention.

Show it:

1A an embodiment of a high-pressure pump with integrated coolant and / or lubricant supply,

1B a further view of an embodiment of a high pressure pump with integrated coolant and / or lubricant supply,

2 a second embodiment of a high pressure pump with integrated coolant and / or lubricant supply,

3 an embodiment of a high-pressure pump with a spray oil collector,

4A an operation of the spray oil collector of the high pressure pump when collecting spun-off oil,

4B an operation of the spray oil collector in the recycling of collected oil to the drive shaft, and

5 an embodiment of the spray oil collector for returning collected spray oil in the direction of a center of a cam of a drive shaft.

1A shows a cross section through an embodiment of a high-pressure pump 1 with integrated coolant and / or lubricant supply. The high-pressure pump comprises a pump piston 10 and a pestle 20 , For example, a roller tappet, for moving the pump piston 10 , The pump piston 10 is via a piston foot on the plunger 20 supported. The high pressure pump further includes a tappet guide 30 to guide the plunger 20 on. The ram guide 30 can be formed by the actual pump housing of the high-pressure pump. The plunger guide may be formed as a hollow body with a cavity, wherein the plunger 20 is guided in the cavity. Between a cavity facing the inner wall I30 of the tappet guide 30 and the pestle 20 a gap S is formed.

The high pressure pump further includes a roller 40 to rest on a drive shaft 2 , The role 40 is at one end of the tappet guide 30 arranged inside the cavity of the tappet guide or the pump housing and with the plunger 20 coupled. The role 40 can be on a tread of a cam 5 the drive shaft 2 rest. The pump piston 10 and the pestle 20 be through a preloaded spring 70 to the cam 5 the drive shaft 2 pressed. The spring can be considered a pump piston 10 surrounding and in the ram body 20 be formed protruding helical compression spring. With a rotation of the drive shaft 2 and thus the cam 5 is the rotational movement of the drive shaft over the roller 40 and the pestle 20 in a stroke movement of the pump piston 10 transformed. The ram guide 30 or the pump housing of the high pressure pump has at least one channel 31a . 31b respectively 32 for supplying the coolant and / or lubricant 3 to the role 40 ( 1A and 1B ) and / or the gap S ( 2 ) on.

The 1A and 1B show an embodiment of the high-pressure pump, in which in the pump housing or in the tappet guide the high-pressure pump channels 31a . 31b are provided, over the coolant and / or lubricant 3 from a ring channel 33 to the role 40 arrives. For the formation of the annular channel, the ram guide 30 on an outer wall A30 a recess 33 on, in the circumferential direction of the tappet guide 30 runs. The ram guide 30 furthermore has at least one groove on the outer wall A30 34 for receiving a seal 4 on, with the groove 34 also in the circumferential direction of the tappet guide 30 runs. When installing the high-pressure pump in an engine block 6 is between the engine block and the pump housing or the tappet guide 30 in the area of the indentation 33 formed a ring channel.

The engine block 6 has a transverse bore 7 on that with the oil circuit of the engine block 6 connected is. Through the cross hole 7 can the ring channel 33 and thus the channels 31a . 31b Coolant and / or lubricant 3 , For example, engine oil, are supplied from the oil circuit of the engine. The oil passes over the channels 31a . 31b to the desired contact points of the drive elements of the high pressure pump, in particular to the role 40 , The channels 31a . 31b have to a first end E31a, in the indentation 33 on the outer wall A30 of the tappet guide 30 opens. Furthermore, the channels have 31a . 31b a second end E31b located at a location on the inner wall 130 of the tappet guide 30 opens into the cavity of the tappet guide, so that the coolant and / or lubricant 3 from the second end E31b of the channels 31a . 31b to the role 40 arrives.

According to a possible embodiment of the high-pressure pump, at the second end E31b of the channels 31a . 31b a nozzle 50 be arranged. The nozzle 50 serves to generate a jet of coolant and / or lubricant 3 in the direction of the roll 40 ,

The channels 31a . 31b can as bores, for example as longitudinal bores, in the tappet guide or the pump housing 30 be provided. By choosing different cross sections of the channels 31a . 31b or by the provision of nozzles at the ends E31b of the channels 31a . 31b It is possible to influence the amount of coolant and / or lubricant in the channels via hydraulic throttling independently of one another with known available supply pressure. By attached to the channel ends E31b various nozzles can also be influenced in a targeted way and the location of the coolant and / or lubricant.

2 shows a further embodiment of the high-pressure pump, in which the pump housing or the tappet guide 30 a channel 32 for cooling and / or lubricant supply into the gap S between the plunger 20 and the ram guide 30 having. The channel 32 can as a bore, for example as a longitudinal bore, in the pump housing or the tappet guide 30 be educated. The channel 32 has a first end E32a, which is in the recess 33 the ram guide opens. Through the in the grooves 34 arranged seals 4 When installing the high-pressure pump in a motor block between the pump housing and the engine block, a sealed annular channel formed by the oil from the oil circuit of the engine in the channel 32 flows. The channel 32 has another end E32b at which the channel 32 in the gap S between the plunger 20 and the ram guide 30 empties. By means of the canal 32 can thus coolant and / or lubricant in the gap S between plunger 20 and ram guide 30 reach.

3 shows a further embodiment of the high-pressure pump 1 in which the pump housing or the housing of the tappet guide 30 is shaped such that at the end of the tappet guide 30 on which the role 40 is arranged, a spray oil collector 60 is trained. The spray oil collector 60 is suitable for collecting oil that occurs during a rotation of the drive shaft 2 from the drive shaft or the cam 5 is thrown away. The spray oil collector 60 For example, it can be designed as an incision in the pump housing in the axial direction of the drive shaft. The spray oil collector 60 is formed such that upon rotation of the drive shaft 2 or the cam 5 in the direction of the spray oil collector 60 thrown off oil from the spray oil collector 60 collected and then back to the drive shaft 2 or the cam 5 running.

4A shows a rotation of the drive shaft 2 or the cam 5 , The arrows indicate a path of the ejected from the drive shaft or the cam splash oil. Part of the ejected spray oil becomes the roll by the shape of the spray oil collector 40 or the plunger 20 guided. Another part of the thrown-off oil is collected on a bottom surface of the tappet guide, which may be formed as a spray oil collector, and concentrated there. Based on 4B it becomes clear that the oil collected on the bottom surface of the tappet guide runs to the edges of the spray oil collector and from there back onto the cam 5 drips. Due to the geometric shape of the pump housing to form the spray oil collector can thus the coolant and / or lubricant 3 be held or collected in the field of drive elements, in particular the role and the plunger, the high-pressure pump.

5 shows a further embodiment of the high-pressure pump, wherein the spray oil collector 60 a drip edge 61 having. The drip edge 61 is formed such that of the spray oil collector 60 during the rotation of the drive shaft 2 or the cam 5 thrown and collected oil along the bottom surface of the spray oil collector to the drip edge 61 running. From the drip edge 61 the collected oil drips back onto the drive shaft 2 or the cam 5 , With appropriate design of the bottom surface, for example, if the bottom surface or its edge is designed slightly sloping inward, the effluent oil is directed towards the center of the cam and drips there on the tread.

By means of the specified embodiments of the high-pressure pump, it is possible to use cooling and / or lubricant of an internal combustion engine for cooling and lubricating the drive elements of the high-pressure pump and to lubrication and cooling-intensive areas of the high pressure pump or the drive of the high pressure pump, in particular the roller and the plunger. respectively. By a targeted amount of coolant and / or lubricant can be placed in the tribologically and thermally differently stressed contact points on the drive of the high-pressure pump, it is possible to ensure the robustness of the high pressure pump or increase.

LIST OF REFERENCE NUMBERS

1

high pressure pump

2

drive shaft

3

Coolants and lubricants

4

poetry

5

cam

6

block

10

pump pistons

20

tappet

30

tappet guide

40

role

50

jet

60

Oil-collector

70

feather

Claims (10)

High-pressure pump with integrated coolant and / or lubricant supply, comprising: - a pump piston ( 10 ), - a pestle ( 20 ) for moving the pump piston ( 10 ), - a tappet guide ( 30 ) for guiding the plunger ( 20 ), wherein the ram guide ( 30 ) is formed as a hollow body with a cavity, wherein the plunger ( 20 ) is guided in the cavity, wherein between a cavity facing the inner wall (I30) of the tappet guide ( 30 ) and the plunger ( 20 ) a gap (S) is formed, - a roll ( 40 ) for resting on a drive shaft ( 2 ), where the role ( 40 ) at one end of the tappet guide ( 30 ) is arranged inside the cavity and with the plunger ( 20 ), wherein the tappet guide ( 30 ) at least one channel ( 31a . 31b . 32 ) for supplying the coolant and / or lubricant ( 3 ) to the role ( 40 ) and / or the gap (S). High-pressure pump according to claim 1, - wherein the tappet guide ( 30 ) on an outer wall (A30) of the tappet guide ( 30 ) a recess ( 33 ), which in the circumferential direction of the tappet guide ( 30 ), wherein - the ram guide ( 30 ) on the outer wall (A30) at least one groove ( 34 ) for receiving a seal ( 4 ), wherein the groove ( 34 ) in the circumferential direction of the tappet guide ( 30 ) runs. High-pressure pump according to claim 2, wherein the at least one channel ( 31a . 31b . 32 ) has a first end (E31a, E32a), which in the indentation ( 33 ) on the outer wall (A30) of the tappet guide (A30) 30 ). High-pressure pump according to claim 3, - wherein the at least one channel ( 31a . 31b . 32 ) a longitudinal bore ( 311 . 321 ), wherein the longitudinal bore ( 311 . 321 ) in the tappet guide ( 30 ) in the longitudinal direction of the plunger ( 20 ) runs. High-pressure pump according to one of claims 1 to 4, comprising: - a first of the at least one channel ( 31a . 31b ) for supplying the coolant and / or lubricant ( 3 ) to the role ( 40 ), The first channel ( 31a . 31b ) has a second end (E31b), the second end (E31b) of the first channel (E31b) 31a . 31b ) at a first position on the inner wall (I30) of the tappet guide ( 30 ) opens into the cavity so that the coolant and / or lubricant ( 3 ) from the second end (E31b) of the first channel ( 31a . 31b ) to the role ( 40 ). High pressure pump according to claim 5, comprising: - a nozzle ( 50 ) for generating a jet of coolant and / or lubricant ( 3 ) in the direction of the roll ( 40 ), - the nozzle ( 50 ) at the second end (E31b) of the first channel ( 31a . 31b ) is arranged. High-pressure pump according to one of claims 1 to 6, comprising: - a second of the at least one channel ( 32 ) for supplying the coolant and / or lubricant ( 3 ) to the gap (S) between the inner wall (I30) of the tappet guide ( 30 ) and the plunger ( 20 ), The second channel ( 32 ) has a second end (E32b), the second end (E32b) of the second channel (E32b) 32 ) at a second location on the inner wall (I30) of the tappet guide ( 30 ) opens into the cavity so that the coolant and / or lubricant ( 3 ) from the second end (E32b) of the second channel ( 32 ) in the gap (S) between the inner wall (I30) of the tappet guide ( 30 ) and the plunger ( 20 ). High-pressure pump according to one of claims 1 to 7, - wherein the tappet guide ( 30 ) at the end where the roll ( 40 ) is shaped in such a way that at the end of the tappet guide ( 30 ) a spray oil collector ( 60 ), - wherein the spray oil collector ( 60 ) is formed for collecting oil, which upon rotation of the drive shaft ( 2 ) is thrown away from the drive shaft. High-pressure pump according to claim 8, wherein the spray oil collector ( 60 ) is designed such that during the rotation of the drive shaft ( 2 ) in the direction of the spray oil collector ( 60 ) ejected oil from the spray oil collector ( 60 ) back to the drive shaft ( 2 ) running. High-pressure pump according to claim 9, - wherein the spray oil collector ( 60 ) a drip edge ( 61 ), wherein the drip edge ( 61 ) is designed such that the of the spray oil collector ( 60 ) during the rotation of the drive shaft ( 2 ) collected oil to the drip edge ( 61 ) and from the drip edge ( 61 ) on the drive shaft ( 2 ) drips.

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