WO2005111495A1

WO2005111495A1 - Lubricant pump

Info

Publication number: WO2005111495A1
Application number: PCT/EP2005/004367
Authority: WO
Inventors: Zdravko Paluncic
Original assignee: Lincoln Gmbh & Co. Kg
Priority date: 2004-05-14
Filing date: 2005-04-22
Publication date: 2005-11-24
Also published as: DE112005001039A5

Abstract

The invention relates to a pump for lubricating at least one lubrication point on a hydraulic device, e.g. on a hydraulic sledgehammer, comprising a base body (1) with a pressure reduction assembly (2, 3; 27, 28). According to the invention, the hydraulic pressure of the hydraulic device can be transferred to the lubricant in a lubricant chamber (5) after being reduced in a specific ratio, optionally by means of a piston (3, 3') or similar pressure transfer device, via a hydraulic inlet (4') in such a way that the lubricant can be delivered at a correspondingly low pressure from at least one lubricant outlet (6) into at least one lubricant conduit that leads to the respective lubrication point(s) of said hydraulic device.

Description

lubrication pump

The invention relates to a pump for lubricating at least one lubrication point on a hydraulic device, e.g. on a hydraulic hammer.

The object of the invention is to propose such a lubricant pump with a small footprint, inexpensive to manufacture and simple operation.

To achieve this object, the lubricant pump of the type mentioned at the outset has a base body which has a pressure reducing arrangement, the hydraulic pressure of the hydraulic device after reduction in a certain ratio, possibly via a piston or the like.pressure transmission device, to the lubricant via a hydraulic inlet can be transferred to a lubricant chamber so that the lubricant with a correspondingly lower lubricant pressure can be dispensed from at least one lubricant outlet to at least one lubricant line to the respective lubrication point (s) of the hydraulic device.

Such a lubricant pump can be manufactured very compactly at low cost due to its simple structure. The pressure reduction ensures that during the period of operation of the hydraulic device uniform lubrication of the hydraulic device takes place with a lubricant pressure which is correspondingly low compared to the hydraulic pressure of the hydraulic device to be lubricated.

In a first embodiment of the invention, the pressure reducing arrangement has a differential piston arrangement of a predetermined reduction ratio, the higher hydraulic pressure of the hydraulic device acting on a control piston with a small effective cross section being transferable to a follower piston having a larger effective cross section acting on the lubricant in a lubricant chamber via the hydraulic inlet.

For a compact design, the control piston and the follower piston of the differential piston arrangement are advantageously accommodated coaxially in the base body.

The reliability of the mode of operation of the control pistons and / or the follower pistons is / is sealingly guided on the walls of the base body.

According to an alternative embodiment of the invention, the pressure reducing arrangement has a pressure limiting valve arrangement.

The pressure reduction ratio of the pressure reduction arrangement is preferably selected such that the pressure in the lubricant chamber overcomes the flow resistances of the lubricant on the way to the respective lubrication point of the hydraulic device during operation of the hydraulic device.

In particular, it is provided in the invented lubricant pump that when the hydraulic pressure is between approximately 80 and 140 bar during operation of the hydraulic device, the lubricant pressure is between approximately 5 and 10 bar. The invention further proposes to provide at least one adjustable throttle and / or at least one metering valve in the at least one lubricant outlet in order to be able to regulate or meter the amount of lubricant delivered by the lubricant pump as desired.

A further improvement can be achieved in that, when designing the inventive concept, the piston, like the follower piston, works against the effect of a return spring when pressure is applied. This makes refilling the lubricant chamber easier.

In order to avoid the creation of a vacuum behind the piston that can be moved in the lubricant chamber, such as the follower piston, when it is actuated while the lubricant is being dispensed, the lubricant chamber on the trailing side of the piston, such as the follower piston, can be connected to the outside atmosphere via a ventilation device ,

The lubricant chamber is preferably filled via a filling device which opens into the lubricant chamber on the feed side of the piston, such as the follower piston. This can be equipped with a full notification facility.

Another optional feature of the invention is that the piston, like the follower piston, cooperates with an empty signaling device to indicate when the lubricant chamber is empty and has to be refilled.

In the case of the pressure reducing arrangement being designed as a pressure limiting valve arrangement, the lubricant chamber on the trailing side of the piston preferably has a return valve for the hydraulic medium. Such an empty indicator device can, for example, have a spring-biased indicator pin, on which the piston, possibly the Foie piston, acts when the lubricant dispensing has ended.

A further improvement of the inventive concept results when the lubricant pump is equipped with means for interrupting the hydraulic supply to the hydraulic device as soon as the lubricant chamber is empty. This ensures that the hydraulic device cannot be operated without lubrication.

This can in particular be achieved in a simple manner by leading the hydraulic supply line of the hydraulic device through the base body of the lubricant pump and, when the lubricant chamber is empty, e.g. is interrupted by a control piston, such as the control piston of the differential piston arrangement in its empty position.

Further objectives, features, advantages and possible uses of the invention result from the following description of embodiments with reference to the drawing. All of the described and / or illustrated features, alone or in any combination, form the subject matter of the invention, regardless of their combination in individual claims or their relationship.

Show it:

1 schematically, in vertical longitudinal section, a lubricant pump having the invention,

2 shows another embodiment of a lubricant pump according to the invention, 3 shows a further embodiment of the invention, and

4a and 4b a still further embodiment of the invention in two orthogonal vertical longitudinal sections.

The lubricant pump shown in FIG. 1 has an essentially two-part main body 1. The base body 1 can be attached, for example, via threaded bores 19 to a hydraulic device, such as a hydraulic hammer, whose or its lubrication points are to be lubricated. The upper part 1a of the base body 1 is penetrated by a central bore 4, which forms a hydraulic inlet 4 'for the hydraulic medium of the hydraulic device. The bore 4 extends into a lubricant chamber 5 of the lower part 1b of the base body 1. In the bore 4 is a cylindrical control piston 2, which can be acted upon by the hydraulic pressure of the hydraulic device, such as the hydraulic hammer, and a differential piston arrangement 2, 3 serving to reduce the pressure - slidably mounted. The control piston 2 is sealed against the wall 7 of the bore 4. Instead of the piston 3, other pressure transmission devices, such as a bellows, can also be considered, on the basis of which the fill level of the chamber 3 can be easily recognized. This also applies accordingly to the embodiments of the invention described below.

In the hollow cylindrical lubricant chamber 5 provided in the lower part 1b of the base body 1 for receiving lubricant to be dispensed, a cylindrical follower piston 3 of the differential piston arrangement 2, 3, which can be acted upon by the control piston 2, is slidably arranged coaxially to the control piston 2 and against it Wall 8 of the lubricant chamber 5 guided sealingly. The cross section of the follower piston 3 is corresponding the desired pressure reduction or pressure reduction ratio is greater than the cross section of the control piston 2.

In the upper end wall surface of the lubricant chamber 5, an external ventilation device 13, optionally with a filter, opens into the bottom surface of the lubricant chamber 5, a corner duct 15 'of a filling device 15 for lubricant opens.

The lower end of a channel section 15 ″ branching outward from the corner channel 15 ′ carries a full signaling device 18. This essentially has a spring-preloaded valve ball 18 ′, which lifts off its valve seat as soon as, as is the case when the lubricant chamber 5 is completely filled, the lubricant pressure exceeds a predetermined value.

From the bottom surface of the lubricant chamber 5 also branches off a lubricant outlet 6, which is associated with a throttle 9. With the help of the throttle 9, the lubricant delivery can be regulated.

It can be seen that the cross section of the control piston 2 (for example a factor of 10: 1) is significantly smaller than the cross section of the following piston 3, as a result of which the pressure reduction ratio is determined. In the case of a hydraulic hammer, the hydraulic pressure which is present at the hydraulic inlet 4 during operation is, for example, between 80 and 140 bar, and the lubricant pressure prevailing in the lubricant chamber 5 is, for example, 10 bar. The pressure reduction ratio and thus the pressure in the lubricant chamber 5 are selected such that the lubricant can be passed through the lubricant outlet 6 with the throttle 9 and the lubricant line connected there against the flow resistance up to the respective lubrication point of the hydraulic device, such as the hydraulic hammer is promoted. It can also be seen that all the bores in the base body 1 or its two parts are placed in such a way that they can easily be introduced from the outside. The alternative embodiment of the invention shown in FIG. 2 works on the same basic principle as that shown in FIG. 1. The former differs from the latter in the following points:

When the hydraulic device and thus the control piston 2 are actuated, the follower piston 3 works against the action of a return spring 11, which in the illustrated case is arranged coaxially with the follower piston 3 on its feed side 14 in the lubricant chamber 5 and on the one hand on the feed side 14 of the follower piston 3 and on the other hand is supported on the bottom surface of the lubricant chamber 5. The return spring 11 serves to relieve the pressure in the lubricant chamber 5 when the hydraulic pressure drops, that is to say when the hydraulic device is switched off. The return spring 11 can also be at least partially received in the follower piston 3 to reduce the block height of the base body 1.

Instead of the throttle 9 of FIG. 1, a metering valve 10 is provided in the lubricant outlet 6 according to FIG. 2. The metering valve 10 of a known type (for example, EOS ESILUB Oil System from the applicant) is used for more precise metering of lubricant by having a combination of a shuttle valve 22 and a metering disk 23. In the pressure phase of the lubricant pump, a metering chamber of the metering valve 10 is filled. When the hydraulic pressure applied to the lubricant pump has dropped, the lubricant pressure is reduced so that the metering valve 10 can shift.

According to FIG. 2, the follower piston 5 also interacts with an empty alarm device 16. This has an internally pre-stressed colored display pin 17, which is retracted in the retracted position of the follower piston 3 in the base body 1, and correspondingly visibly protrudes out of the base body 1 when the lubricant chamber 5 is completely emptied due to the completely advanced follower piston 3.

As long as the hydraulic device is working, the lubricant in the lubricant chamber 5 is constantly under the lubricant pressure, with the aid of which the lubricant is conveyed to the lubrication point or the lubrication points.

The two types of embodiment shown are based on the principle of introduction. The pump can also be designed as a multi-line pump by providing several lubricant outlets with corresponding throttles or corresponding metering valves on the base body 1.

3, the same elements are provided with the same reference numerals as in FIGS. 1 and 2. In addition to the previous embodiments, means for interrupting the hydraulic supply of the hydraulic device are provided to ensure the correct operation of the hydraulic device which is to be lubricated. These are effective as soon as the lubricant chamber 5 is empty. For this purpose, the hydraulic supply line of the hydraulic device to be lubricated is led from the hydraulic inlet 4 ¹ to a hydraulic outlet 4 ″ across the base body 1 of the lubricant pump, so that the hydraulic medium controls a control chamber 25 delimited by the control piston 2 from the hydraulic inlet 4 ′ to the hydraulic outlet 4 "flows as long as the control piston 2 is not yet in its lowest empty position in the drawing, which it occupies when the lubricant chamber 5 is empty. In this empty position, the control piston 2 then blocks the passage of the hydraulic medium with its upper blocking section 26, so that the operation of the hydraulic preliminary direction is interrupted. The upper end of the bore 4, in which the control piston 2 moves, is provided with a closure 24.

4a and 4b schematically illustrate, in two orthogonal longitudinal sections, another embodiment of the invention, in which the pressure-reducing arrangement is formed by a pressure-limiting valve arrangement 27, 28 instead of a differential piston arrangement 2, 3. In this case, behind the hydraulic inlet 4 ′, a connection channel 28, which is guided through a corner, branches off from the bore 4 into the (in the drawing upper) end face of the lubricant chamber 5. An adjustable pressure limiting valve 27 acts in the connecting channel 28. The reduced pressure acts on the individual piston 3 ¹ or the like, which is mounted displaceably in the lubricant chamber 5.

In this case, the base body 1 is constructed in three parts, an upper part 1a with the bore 4 forming the hydraulic inlet 4 ', the pressure relief valve 27 and the connecting channel 8, the lower part 1b with a filling device 15, 15', an empty signaling device 16 and a full alarm device 18 and a lubricant outlet 6 with throttle 9, and with a central part 1c, which connects the two parts 1a and 1b as a cylindrical tube and forms the outer boundary of the lubricant chamber 5, the parts 1a, 1b and 1c are against each other sealed.

In order to be able to easily fill the lubricant chamber 5 with new lubricant, the bore 4 opening into the end face of the lubricant chamber 5 on the trailing side of the piston 3 'has a return valve 29 for the hydraulic medium located behind the piston 3'. The return valve 29 is designed as a spring-biased check valve. LIST OF REFERENCE NUMBERS

1 basic body

1a upper part

1 b lower part

1c middle part

2 control pistons

3 follower pistons

3 'piston bore' hydraulic inlet "hydraulic outlet lubricant chamber lubricant outlet wall throttle 0 metering valve 1 return spring 2 trailing side 3 ventilation device 4 leading side 5 filling device 5 'channel, corner channel 5" channel section 6 empty indicator 7 indicator pin 8 full indicator 8' valve ball threaded holes

Return spring

shuttle valve

metering

shutter

control chamber

blocking portion

Pressure relief valve

connecting channel

Return valve for hydraulic medium

Claims

claims:

1. Pump for lubricating at least one lubrication point on a hydraulic device, e.g. on a hydraulic hammer, with a base body (1) which has a pressure reducing arrangement (2, 3; 27, 28), the hydraulic pressure of the hydraulic device after reduction in a certain ratio, possibly via a hydraulic inlet (4 ') a piston (3, 3 ') or the like. Pressure transmission device to which lubricant can be transferred in a lubricant chamber (5), so that the lubricant with a correspondingly lower lubricant pressure from at least one lubricant outlet (6) to at least one lubricant line to the respective one or more Lubrication point (s) of the hydraulic device can be delivered.

2. Pump according to claim 1, characterized in that the pressure reducing arrangement has a differential piston arrangement (2, 3) of a predetermined reduction ratio, with the hydraulic inlet (4 ') acting on a control piston (2) having a smaller effective cross-section than the hydraulic pressure of the hydraulic device the lubricant in a lubricant chamber (5) acting follower piston (3) of larger cross section can be transferred.

3. Pump according to claim 2, characterized in that the control piston (2) and the follower piston (3) are slidably received coaxially in the base body (1).

4. Pump according to one of claims 2 or 3, characterized in that the control piston (2) and / or the follower piston (3) on the inner walls (7, 8) of the base body (1) are / is sealingly guided.

5. Pump according to one of the preceding claims, characterized in that the pressure reducing arrangement (3, 3; 27, 28) has a pressure limiting valve arrangement (27, 28).

6. Pump according to one of the preceding claims, characterized in that the pressure reduction ratio of the pressure reducing arrangement (2, 3; 27, 28) is selected so that the pressure in the lubricant chamber (5) the flow resistance of the lubricant on the way to the respective lubricating point - overcomes the hydraulic device.

7. Pump according to one of the preceding claims, characterized in that when the hydraulic pressure is between approximately 80 and 140 bar during operation of the hydraulic device, the lubricant pressure is between approximately 5 and 10 bar.

8. Pump according to one of the preceding claims, characterized in that at least one adjustable throttle (9) and / or at least one metering valve (10) are / is provided in the at least one lubricant outlet (6).

9. Pump according to one of the preceding claims, characterized in that the piston (3, 3 ') is supported on its feed side (14) on a return spring (11).

10. Pump according to one of the preceding claims, characterized in that the lubricant chamber (5) on the trailing side (12) of the piston (3, 3 ') is connected to an external atmosphere via a ventilation device (13).

11. Pump according to one of the preceding claims, characterized in that the lubricant chamber (5) on the feed side (14) of the piston (3, 3 ') with a filling device (15, 15') which may have a full signaling device (18). ) is connected for lubricant.

12. Pump according to one of the preceding claims, characterized in that the piston (3, 3 ') cooperates with an empty alarm device (16).

13. Pump according to claim 11, characterized in that the empty indicator (16) has a spring-biased indicator pin (17), on which the piston (3, 3 ') acts in its empty position.

14. Pump according to one of claims 5 to 13, characterized in that the lubricant chamber (5) on the trailing side of the piston (3 ') has a return valve (29) for the hydraulic medium.

15. Pump according to one of the preceding claims with means for interrupting (interrupting means) the hydraulic supply of the hydraulic device as soon as the lubricant chamber (5) is empty.

16. Pump according to claim 15, characterized in that the hydraulic supply line of the hydraulic device is guided through the base body (1) and, when the lubricant chamber (5) is empty, e.g. is interrupted by a control piston, such as the control piston (2) of the differential piston arrangement (2, 3) in its empty position.