US20110274567A1

US20110274567A1 - Lubricant pump and machine with such a lubricant pump

Info

Publication number: US20110274567A1
Application number: US13/101,290
Authority: US
Inventors: Rainer Schmitt; Tobias Mueller; Andreas Schoenfeld
Original assignee: Lincoln GmbH
Current assignee: SKF Lubrication Systems Germany GmbH
Priority date: 2010-05-05
Filing date: 2011-05-05
Publication date: 2011-11-10
Also published as: EP2385290A1; DE202010006498U1; EA201100599A1

Abstract

The invention pertains to a lubricant pump for conveying lubricant to at least one lubricating point, wherein said lubricant pump features a first pump unit and a drive assigned thereto. According to the invention, another pump unit is also provided and coupled to the first pump unit, wherein the other pump unit can be driven simultaneously with the first pump unit by means of the drive of the first pump unit.

Description

FIELD OF INVENTION

The present invention pertains to a lubricant pump for conveying lubricant to at least one lubricating point, featuring a pump unit with at least one input shaft, at least one pump element for conveying lubricant, and means for driving the at least one pump element by means of the input shaft. The invention furthermore pertains to a machine with such a lubricant pump.

BACKGROUND OF INVENTION

For example, a pump of this type that is suitable for supplying lubricating points with oil or the like is known, e.g., from DE 20 2006 005 682 U1. In a few applications such as, e.g., in baling presses, it is necessary to supply individual lubricating points with different lubricants, e.g., oil and grease. Until now, this was realized with separate pumps that respectively have their own power sources. With respect to the required structural space and the number of required components, this pump is considered to be in need of improvement.
It is therefore the objective of the invention to propose a lubricant pump of the above-described type that has a simple and compact design and is suitable for supplying individual lubricating points with different lubricants.

SUMMARY OF THE INVENTION

This objective is attained with a pump according to Claim 1. The invention is based on the notion of creating a tandem pump that can drive different pump units for supplying lubricating points with different lubricants by means of a single drive.
The first pump unit of the inventive lubricant pump is realized, for example, similar to the pump known from DE 20 2006 005 682 U1. According to one preferred embodiment of the invention, another pump unit is provided in addition to this first pump unit and coupled thereto, wherein this other pump unit also features at least one pump element for conveying grease or a similar lubricant and additional means for driving this at least one pump element. In this case, these additional means of the (second) pump unit are connected to the input shaft of the first pump unit or an output shaft of the first pump unit in order to be driven. In other words, either an input shaft is provided that simultaneously drives both pump units or an output shaft or a device for receiving the input shaft of the second pump unit is provided within the first pump unit such that both pump units can be jointly driven when driving the input shaft of the first pump unit.
In this context, the present invention is not limited to embodiments, in which oil is pumped in the first pump unit that features the (joint) input shaft and grease is pumped in the second pump unit. Both pump units, in principle, are suitable for conveying lubricants. This means that either identical or different lubricants can be conveyed with the two pump units. When conveying different lubricants, it is irrelevant whether the lubricant with the higher viscosity is conveyed in the first pump unit or another pump unit.
The inventive design of the lubricant pump in the form of a tandem pump with only one input shaft or only one drive results in a compact design and can be installed easier than solutions with different lubricant pumps. In addition, cost advantages are attained because only a single drive is required. This can be realized mechanically or in other suitable ways.
In order to simplify the exchange of the individual pump units, it is preferred that each of the pump units features a separate housing. In this respect, the housings of the pump units may be connected to one another such that they form a common unit. However, this is preferably realized in such a way that the housings can be separated from one another in a nondestructive fashion, for example, with screw connections. In this respect, it is particularly preferred if the housings are adapted to one another for the assembly, e.g., by providing the two pump units with mutually assigned connecting means such as through-openings for screws, pocket or threaded holes or the like. If each of the two pump units features a separate housing, it is also possible to largely utilize existing components for the inventive tandem lubricant pump.
It is preferred to integrate a lubricant reservoir into at least one of the pump units. This is particularly advantageous for a pump unit that serves for conveying grease. However, it would alternatively also be possible that at least one of the pump units features a separate lubricant reservoir that is connected to the respective pump unit via a suitable lubricant line. This solution is frequently preferred for conveying oil to different lubricating points.
According to an additional development of the invention, it is proposed that the first pump unit features a connecting region for connecting the other pump unit, wherein the other pump unit does not extend beyond the connecting region in at least one direction. In other words, the first pump unit features a region that is not covered by the other pump unit in the assembled state of the two pump units. If the input shaft is arranged in the first pump unit outside of this connecting region, a particularly space-saving design can be achieved while preventing the other pump unit from covering the installation space for the input shaft of the first pump unit.
With respect to the accessibility of, if applicable, several pump elements, it is preferred to respectively arrange these pump elements on the side of a pump unit that faces away from the other pump unit. This makes it possible to exchange individual pump elements without having to dismount the entire lubricant pump with both pump units. This furthermore provides advantages with respect to the options for connecting the lubricant lines leading away from the pump elements. Monitoring the function of the pump elements is also simplified in this fashion.
The means for driving one of the pump elements may comprise, for example, a swash plate and/or a cam plate.
It furthermore proved particularly advantageous to provide the first pump unit with another input shaft, to which is assigned a transmission that can be coupled to the means for driving the pump elements. In this way, the different transmission ratios make it possible to actuate the pump units with different speeds depending on which of the two input shafts drives the inventive tandem lubricant pump.
The invention furthermore pertains to a machine such as, for example, a baling press with at least one lubricating point to be supplied with oil and at least one lubricating point to be supplied with grease. For this purpose, the inventive machine features at least one tandem lubricant pump of the above-described type in order to respectively supply the lubricating points with oil and grease. However, it would also be possible, in principle, to use lubricants other than oil or grease in the inventive machine.
The invention is described in greater detail below with reference to the drawings. In this case, all described and/or graphically illustrated characteristics form the object of the invention individually or in any sensible combination, regardless of their combination in the claims or their references to other claims.

BRIEF DESCRIPTION OF THE DRAWINGS

In the schematic drawings:

FIG. 1 shows a perspective representation of an inventive lubricant pump prior to assembly,

FIG. 2 shows another perspective representation of the lubricant pump according to FIG. 1 prior to assembly,

FIG. 3 shows a side view of the lubricant pump according to FIGS. 1 and 2 in the assembled state, and

FIG. 4 shows a sectional representation of a pump unit realized similar to that shown in FIGS. 1-3.

DETAILED DESCRIPTION

FIGS. 1-3 show a tandem lubricant pump 1 that essentially consists of two pump units 2, 3. In this case, the first pump unit 2 is realized similar to that of the lubricant pump known from DE 20 2006 005 682 U1, to which the application hereby refers. On an outer side, this pump unit 2 features twelve openings 4, in which a pump element 5 can be respectively installed as indicated in FIG. 4.
In the embodiment according to FIGS. 1-3, the pump unit 2 is provided with two input shafts 6 a, 6 b that protrude out of the pump unit 2 on the opposite side with reference to the openings 4 for the pump elements 5. Each of these input shafts 6 a, 6 b can be connected to a drive that is not illustrated in the figures. Gearwheels of a transmission are assigned to the input shafts 6 a, 6 b in the interior of the pump unit 2 such that the pump unit 2 operates with different speeds depending on which of the two input shafts 6 a, 6 b is driven. Consequently, only one of the two drive shafts 6 a, 6 b is ever used during the operation of the pump.
In the illustration according to FIG. 1, a connecting region 7 is provided above the two drive shafts 6 a, 6 b and features several connecting elements in the form of threaded bores 8 for connecting the other pump unit 3. This connecting region 7 is furthermore provided with a hollow shaft journal 9 that is driven by an output shaft of the first pump unit 2 when driving one of the two input shafts 6 a or 6 b.
The second pump unit 3 is equipped with an integrated lubricant reservoir 10. An input shaft 11 of the pump unit 3 can be connected to the hollow shaft journal 9 of the first pump unit 2 such that the second pump unit 3 is also driven via the hollow shaft journal 9 and the input shaft 11 when driving one of the input shafts 6 a or 6 b of the first pump unit 2. A connecting plate with several openings 12 arranged therein is furthermore arranged in the second pump unit 3. The arrangement of the openings 12 is adapted to the positions of the threaded bores 8 of the first pump unit such that the two pump units 2, 3 can be connected with the aid of screws 13.
Instead of a hollow shaft journal 9, the first pump unit 2 may also feature an output shaft or a shaft receptacle, namely depending on whether a shaft receptacle is provided on the other pump unit 3 or an input shaft protrudes from the other pump unit 3.
According to the embodiment illustrated in FIG. 4, a swash plate 14 is provided in the interior of the first pump unit 2, wherein two concentric raceways 15 with varying height are provided in said swash plate such that the pump elements 5 accommodated in the different openings 4 can be alternately actuated during a rotation of the swash plate 14.
One or more pump elements may also be provided in the other pump unit 3 and driven, for example, by means of a (not-shown) cam plate.
It would be possible, in principle, to provide gearwheel transmissions in one or both pump units 2, 3 such that the rotational speed of the input shafts 6 a and 6 b differs from the rotational speed, e.g., of the swash plate 14. Furthermore, the means for driving the pump elements such as, e.g., a cam plate, a swash plate or the like can also be actuated with different or identical rotational speeds in both pump units 2, 3. In this way, the conveying speed in the two pump units 2, 3 can also be individually adjusted by selecting the appropriate transmission.
Due to its low manufacturing costs and its small space requirement, the tandem lubricant pump 1 illustrated in the figures is suitable for use in different machines in which different lubricants need to be conveyed. One preferred application in this respect is, e.g., a baling press.

LIST OF REFERENCE SYMBOLS

1 Tandem lubricant pump
2 First pump unit
3 Second pump unit
4 Opening
5 Pump element
6 a, 6 b Input shaft
7 Connecting region
8 Threaded bore
9 Hollow shaft journal
10 Reservoir
11 Input shaft
12 Opening
13 Screw
14 Swash plate
15 Raceway

Claims

1. A lubricant pump for conveying lubricant to at least one lubricating point, comprising a first pump unit and a drive assigned thereto, characterized by the fact that a second pump unit is also provided and coupled to the first pump unit, wherein the second pump unit can be driven simultaneously with the first pump unit by means of the drive of the first pump unit.

2. The lubricant pump, according to claim 1, wherein the first pump unit comprises at least one input shaft, at least a first pump element for conveying oil or a similar lubricant and first means for driving the at least one first pump element by means of the input shaft, and wherein the second pump unit comprises at least a second pump element for conveying grease or a similar lubricant and additional means for driving the second pump element, and wherein said additional means is connected to the input shaft of the first pump unit or an output shaft of the first pump unit in order to be driven.

3. The lubricant pump according to claim 2, characterized by the fact that each of the first and second pump units comprises a separate housing, and wherein the housings of the pump units can be connected into one unit in a separable fashion.

4. The lubricant pump according to claim 2, characterized by the fact that the first and second pump units comprise mutually assigned connecting means.

5. The lubricant pump according to claim 2, characterized by the fact that a lubricant reservoir is integrated into the second pump unit, and by the fact that a separate lubricant reservoir is assigned to the first pump unit and can be connected to the first pump unit via a lubricant line.

6. The lubricant pump according to claim 2, characterized by the fact that the first pump unit comprises a connecting region for connecting the other second pump unit such that the second pump unit does not extend beyond the connecting region in at least one direction, and by the fact that the input shaft is arranged outside of the connecting region in the first pump unit.

7. The lubricant pump according to claim 2, characterized by the fact that the first pump element of the first pump unit is arranged on a side of the first pump unit that faces away from the second pump unit.

8. The lubricant pump according to claim 2, characterized by the fact that the means for driving one of the pump elements comprises a swash plate.

9. The lubricant pump according to claim 2, characterized by the fact that the means for driving one of the pump elements comprises a cam plate.

10. The lubricant pump according to claim 2, characterized by the fact that the first pump unit comprises another input shaft, to which is assigned a transmission that can be coupled to the means for driving the pump elements.

11. A machine comprising at least one lubricating point to be supplied with oil, at least one lubricating point to be supplied with grease, and a lubricant pump according to claim 2 for respectively supplying the lubricating points with oil and grease.

12. The machine of claim 11, wherein the machine is a baling press.

13. The lubricant pump according to claim 1, characterized by the fact that each of the first and second pump units comprises a separate housing, and wherein the housings of the pump units can be connected into one unit in a separable fashion.

14. The lubricant pump according to claim 1, characterized by the fact that the first and second pump units comprise mutually assigned connecting means.

15. The lubricant pump according to claim 1, characterized by the fact that a lubricant reservoir is integrated into the second pump unit, and by the fact that a separate lubricant reservoir is assigned to the first pump unit and can be connected to the first pump unit via a lubricant line.

16. The lubricant pump according to claim 1, characterized by the fact that the first pump unit comprises a connecting region for connecting the second pump unit such that the second pump unit does not extend beyond the connecting region in at least one direction, and by the fact that the input shaft is arranged outside of the connecting region in the first pump unit.

17. A machine comprising at least one lubricating point to be supplied with oil, at least one lubricating point to be supplied with grease, and a lubricant pump according to claim 1 for respectively supplying the lubricating points with oil and grease.

18. The machine of claim 17, wherein the machine is a baling press.