LUBRICANT PUMP WITH AUTOMATICALLY COUPLING PUMP UNIT AND METHOD FOR COUPLING A PUMP UNIT TO A LUBRICANT PUMP

Abstract

A lubricant pump for conveying lubricant from a lubricant reservoir to a pump outlet includes a pump housing with a longitudinal axis. The pump housing has a receiving opening for a pump unit, a lubricant inlet opening and a lubricant outlet opening opening into the receiving opening, a pump drive, and a pump unit with a reciprocatingly movable delivery piston. The pump unit has a suction opening, which corresponds with the lubricant outlet opening when the pump unit is inserted into the receiving opening, and an outlet opening for lubricant. A coupling mechanism for driving the at least one pump unit includes an eccentric element which is rotatable about the longitudinal axis, a drive-side coupling section connected to the eccentric element, and a pump-side coupling section. The drive-side coupling section and the pump-side coupling section can be connected to one another automatically via a resilient latching connection.

Claims

1. Lubricant pump for conveying lubricant from a lubricant reservoir to at least one pump outlet for lubricant, comprising a pump housing with a longitudinal axis (A), wherein the pump housing has at least one receiving opening for a pump unit and a lubricant outlet opening opening into the receiving opening, a pump drive, in particular comprising a drive shaft rotatably mounted in the pump housing, at least one pump unit with a reciprocating delivery piston, wherein the pump unit has a suction opening, which corresponds with the lubricant outlet opening when the pump unit is inserted into the receiving opening, and an outlet opening for lubricant, a coupling mechanism for driving the at least one pump unit, wherein the coupling mechanism comprises: an eccentric element, which is rotatable about the longitudinal axis (A) by the pump drive, in particular by the drive shaft, a drive-side coupling section connected to the eccentric element, and a pump-side coupling section of the at least one pump unit, in particular the delivery piston, wherein the drive-side coupling section and the pump-side coupling section for coupling the pump unit to the pump drive can be connected to one another automatically.

2. Lubricant pump according to claim 1, wherein the drive-side coupling section has or forms at least one drive-side latching element and the pump-side coupling section has or forms a pump-side latching element, which in the coupled state of the pump unit cooperate in a positive-locking manner.

3. Lubricant pump according to claim 1, wherein the drive-side latching element and the pump-side latching element have latching recesses or latching projections, or vice versa, which are shaped to match one another.

4. Lubricant pump according to claim 1, wherein the coupling mechanism comprises at least one resilient latching element, the resilient latching element comprising a resilient drive-side latching element and/or a resilient pump-side latching element, wherein the resilient latching element is in particular elastically deformable and/or resiliently mounted.

5. Lubricant pump according to claim 4, wherein the at least one resilient latching element is displaceable at least substantially parallel to a radial direction (R) of the pump housing.

6. Lubricant pump according to claim 4, wherein the at least one resilient latching element is displaceable at least substantially perpendicular to a radial direction (R) of the pump housing.

7. Lubricant pump according to claim 1, wherein the coupling mechanism comprises a spring element which acts upon a displaceably mounted latching element with a displacement restoring force and is supported against the drive-side coupling section or the pump-side coupling section.

8. Lubricant pump according to claim 1, wherein the coupling mechanism has a displacement guide for a displaceable latching element, which limits the displacement path of the latching element, by stop surfaces, wherein the displacement guide defines a maximum latching position and/or a maximum release position of the latching element.

9. Lubricant pump according to claim 1, wherein the eccentric element is connected in a rotationally fixed manner to the drive-side coupling section, wherein the drive-side coupling section is designed as an eccentric ring which forms a circumferential drive-side latching element.

10. Lubricant pump according to claim 1, wherein the drive-side coupling section comprises a carrier element which is rotatably mounted relative to the eccentric element by at least one rolling bearing, and carries a drive-side latching element.

11. Lubricant pump according to claim 10, wherein a guide element is resiliently mounted in a radially displaceable manner in the pump housing, and the carrier element forms a sliding surface for the forced guidance of the carrier element by the guide element, wherein the carrier element executes a tumbling movement about the longitudinal axis (A).

12. Lubricant pump according to claim 1, wherein the spring element is arranged between the latching element and the carrier element acting parallel to the longitudinal axis (A).

13. Lubricant pump according to claim 1, wherein the displacement guide comprises a guide element for the latching element, which is slidably mounted in the carrier element parallel to the longitudinal axis (A), wherein the guide element is slidably guided in a through opening of the carrier element.

14. Lubricant pump according to claim 1, wherein the guide element forms a stop surface on a side of the carrier element facing away from the latching element, which stop surface defines a maximum latching position of the latching element, wherein the guide element is connected to the latching element on the side facing the latching element.

15. Lubricant pump according to claim 1, wherein the pump-side latching element is formed by a circumferential projection of the delivery piston and/or a drive-side latching element is formed by a latching projection extending transversely to a radial direction (R).

16. Lubricant pump according to claim 1, wherein a latching block carried by the carrier element and mounted displaceably in the carrier element parallel to the longitudinal axis (A) forms a drive-side latching element as a straight latching projection.

17. Lubricant pump according to claim 1, wherein a radially outwardly oriented latching surface of the pump-side latching element and/or a radially inwardly oriented latching surface of the drive-side latching element have a surface section which is beveled with respect to the radial direction (R), wherein the gradients of the surface sections are at least substantially identical, between 15 and 30.

18. Lubricant pump according to claim 1, wherein in the coupled state of the pump unit, an end face of the pump-side latching element, rests against an outer bearing ring of a rolling bearing held by the eccentric element or against an outer surface of the carrier element

19. Lubricant pump according to claim 1, wherein a spring element exerts a contact pressure on the pump-side latching element via beveled surface sections of the drive-side latching element and/or the pump-side latching element against the outer bearing ring of the rolling bearing or the outer surface of the carrier element.

20. Lubricant pump according to claim 1, wherein a guide surface of the pump-side latching element and/or a guide surface of the drive-side latching element is beveled with respect to the radial direction (R), wherein the gradients of the guide surfaces are at least substantially identical and between 20 and 30.

21. Method for coupling a pump unit to a lubricant pump claim 1, insertion of a pump unit into a radially aligned receiving opening of a pump housing of the lubricant pump, wherein the pump housing has a longitudinal axis (A) and has a lubricant outlet opening opening into the receiving opening, wherein the pump unit comprises in particular a reciprocatingly movable delivery piston, a suction opening and an outlet opening for lubricant, optional alignment of the pump unit such that a suction opening of the pump unit corresponds with the lubricant outlet opening, coupling the pump unit to a coupling mechanism of the lubricant pump by producing a resilient latching connection of a pump-side coupling sectionof the pump unit, having a drive-side coupling section which is connected to an eccentric element, wherein the eccentric element is rotatable about the longitudinal axis (A) by a pump drive for driving the coupling mechanism, wherein the latching connection is established automatically by rotation of the eccentric element.

22. Method according to claim 21, wherein, in order to produce the latching connection, a displacement restoring force applied by a spring element to a displaceable drive-side latching element and/or a displaceable pump-side latching element, is overcome.

Description

[0051] Embodiment examples of the disclosure are explained in more detail below by reference to the drawings, wherein:

[0052] FIG. 1 shows a section of an embodiment of the lubricant pump according to the disclosure with a pump unit in the coupled state in a longitudinal sectional view;

[0053] FIG. 2 shows a section of the embodiment as shown in FIG. 1 (rotated 90) with a decoupled pump unit in a longitudinal sectional view;

[0054] FIG. 3a shows a section of the embodiment as shown in FIG. 1 with a latching connection not (yet) made at a first rotational position of the drive shaft in a longitudinal sectional view;

[0055] FIG. 3b shows a section of the embodiment as shown in FIG. 1 with a latching connection not (yet) made at a second rotational position of the drive shaft in a longitudinal sectional view;

[0056] FIG. 4 shows a section of the embodiment as shown in FIG. 1 in a cross-sectional view;

[0057] FIG. 5 shows a section of the embodiment as shown in FIG. 1 in an enlarged longitudinal section view.

[0058] In the following description of the disclosure, the same reference numerals are used for identical and similarly acting elements.

[0059] FIGS. 1 to 5 show an embodiment of a lubricant pump according to the disclosure, wherein a section of a sectional view is shown. FIGS. 1,2, 3a and 3b each show a section of a half-section along the longitudinal axis A of the pump housing 1. FIG. 4 shows a section of a cross-sectional view and FIG. 5 shows an enlarged longitudinal view.

[0060] Two pump units 2 (see FIG. 4) are inserted or can be inserted in one receiving opening 10 each of the pump housing 1. The receiving openings in 10 are aligned in a radial direction R, i.e. they are opened inwards towards the longitudinal axis A or outwards. A pump drive 3 includes a motor (not shown) that drives a drive shaft 30. The drive shaft 30 is rigidly connected to an eccentric element 31. When the pump drive 3 or the drive shaft 30 rotates, the coupling mechanism 4 generates a translatory movement of the delivery piston 20 guided in the pump cylinder 28 via the eccentric element 30, which moves back and forth to perform a suction or pressure stroke. Via a lubricant inlet (not shown) lubricant enters the lubricant pump 100 or the pump housing 1 via a supply line from a lubricant container or directly from a lubricant reservoir and is fed via lubricant channels to the lubricant outlet opening 12. From there, lubricant is sucked in via corresponding suction openings 25 of pump unit 2 during the suction stroke into a dosing volume in pump cylinder 28 and pushed out of the outlet opening 26 during the delivery stroke in order to be guided to a lubrication point via lines to be connected to one or more pump outlets.

[0061] The coupling mechanism 4 has a drive-side coupling section 41 and a pump-side coupling section 21, which according to the disclosure are connected to each other by a latching connection 5 (see FIG. 1). In the figures, the drive-side and pump-side coupling sections 41 and 21 are shown in different positions, respectively. Pump unit 2 is coupled to pump drive 3 in a latching position (see FIG. 1) and can be uncoupled from pump drive 3 in an unlatching position (similar to FIG. 5). When commissioning or servicing the lubricant pump 100, pump units 2 must be coupled and uncoupled, i.e. mounted or dismounted. For this purpose, the pump units 2 are inserted into the receiving openings 10 and pulled out, wherein the latching connection 5 is established or released. An advantage of the disclosure is that the pump units 2 can be very easily inserted into the pump housing 1 in an exclusively radial direction without additional tilting, wherein the coupling sections 21 and 41 engage with each other, preferably automatically, to form the latching connection 5. The pump units 2 are fixed in the pump housing 1 by means of screwed connections 7.

[0062] In the embodiment shown in the figures, the drive-side coupling section 41 is rotatably mounted relative to the eccentric element 31, namely via the rolling bearings 32 and 33, wherein both rolling bearings 32, 33 are designed as radial rolling bearings, each as a ball bearing with an inner bearing ring and an outer bearing ring 34 and 35, respectively. The rolling bearings 32, 33 are formed in a closed and self-lubricating manner. The inner bearing rings are located on the two-part eccentric element 31, which is axially split into two sections. An annular carrier element 43 with a Z-shaped cross-section is mounted on the outer bearing ring 35. In FIGS. 3a and 3b the eccentric element 31 is shown in two different rotational positions.

[0063] In the embodiment shown, a guide element 6 (see FIG. 4), spring-mounted in the pump housing 1, here designed as a guide bolt, rests on the sliding surface 49 of the carrier element 43 and causes a forced guidance of the carrier element 43, which as a result performs a tumbling movement about the longitudinal axis A. The sliding surface 49 is formed by a flat outer circumferential section of the annular carrier element 43.

[0064] In an alternative embodiment, the eccentric element 31 could be connected non-rotatably (i.e. without the roller bearings 32, 33) to the drive-side coupling section 41, i.e. it can be designed as an integral eccentric ring, in which the pump-side coupling section 21 engages.

[0065] In the embodiment shown in the figures, the drive-side coupling section 41 has drive-side latching elements 42 and the pump-side coupling section 21 forms the pump-side latching element 22. The latching element 22 on the pump side is designed as a circumferential projection 23 in the form of a round truncated cone, which is separated from the slidingly guided section of the delivery piston 20 by a circumferential groove 24. In this respect, the circumferential projection 23 forms a piston head of the pump unit 2. The carrier element 43 of the drive-side coupling section 41 carries the latching block 48, which carries the latching projection 46 as a rib extending in a straight manner and projecting from the top side. The latching projection 46 is formed wider than the circumferential projection 23. The latching surfaces 61, 71 of the pump-side and drive-side latching elements 22 and 42 have beveled surface sections 62 and 72. The latching surfaces 61, 71 rest against each other in the latching position to transmit a radial force for a suction stroke. In addition, elements 22, 42 have guide surfaces 63 and 73, on which the latching elements 22, 42 slide along or past each other during an engagement process. This results in a displacement movement of the latching block 48, which is spring-mounted via a spring element 50 (see double arrow in FIGS. 1 and 5). The spring element 50 exerts a displacement restoring force against the displacement movement (upwards in FIGS. 1, 2, 3a, 3b and 5). A displacement guide 44 guides the drive-side latching element 22 or the latching block 48 in axial direction. The displacement guide 44 has a guide element 45 designed as a guide pin, which is slidingly guided in a through opening 53 of an annular peripheral section of the carrier element 43 via a slide bushing. The stop surface 52 in the form of the underside of the latching block 48 defines a maximum (lower) unlocking position, which is not reached in FIG. 3b. Preferably, the release position is not fully reached during coupling in order to fully enable the required displacement of the drive-side latching element 22. The stop surface 51 on the rear side of the head section of the guide element 45 designed as a guide pin defines a maximum (upper) locking position. This maximum latching position is preferably not quite reached with preferably produced latching connection 5, in order to create a coupling mechanism 4 that is as free of play as possible. The spring element 50 is guided in a spring guide opening 47 in the latching block 48 (see FIG. 3b). The spring element 50 presses the latching section 22 on the pump side against the outer bearing ring 34 (see FIG. 1) via the beveled surface sections 62, 72, thus compensating for tolerances and making latching connection 5 free of play. The radial force for a pressure stroke is transmitted directly from the bearing outer ring to the end face 27 of the latching element 22 on the pump side or the circumferential projection 23. The outer bearing ring 34 and/or the latching elements 22, 42, in particular the latching surfaces 61, 71 of the latching elements 22, 42, can be hardened.

[0066] The operation of the lubricant pump 100 or the method according to the disclosure is as follows: The drive shaft 31 rotates (e.g. clockwise) and moves the drive-side coupling section 41 to the delivery piston 20 of pump unit 2 (FIG. 3b). The drive-side coupling section 41 engages in the carrier element 43 (FIG. 4). This is connected to the eccentric element 31 via roller bearings 32, 33. The carrier element 43 is additionally (in FIG. 4 in 12 o'clock position) positively guided by a guide bolt 6. The eccentric element 31 and the guide bolt 6 give the carrier element 43 or the drive-side coupling section 41 a tumbling movement (no pure rotation and no translation). The delivery piston 20 is only engaged with the drive-side coupling section 41. The drive-side coupling section 41 (FIGS. 3b and 5) is displaced in the axial direction by the tumbling movement towards the delivery piston 20 via inclined guide surfaces 63, 73 in the axial direction or pushed away axially (downwards in FIGS. 1, 2, 3a, 3b, 5). When the movement has overcome the inclined guide surfaces 63, 73, a spring element 50 pushes the drive-side coupling section 41 back again (upwards) and the delivery piston of the pump element is coupled with a latching connection 5 with the pump output 3, namely latched (FIG. 1). No additional manual operation is necessary. The latching elements 42 and 22 on the drive side and pump side engage or snap into each other automatically. The coupling sections 21, 41 are first aligned radially to each other by a rotary movement of the pump drive 3 or the drive shaft 30. As the eccentric element 31 shifts the drive-side coupling section 41 outwards, the coupling sections 21 and 41 automatically engage with each other. The delivery piston 20 performs its pumping work in the coupled state with mechanical forced guidance during subsequent operation.

[0067] A lubricant pump 100 according to the disclosure enables a simple and faultless coupling of the pump units 2 to the pump drive 3 via the latching connection 5, which is based in particular on spring-loaded latching elements 22 or 42. The complex and difficult tilting of the pump units 2 when inserting them into the receiving opening 10 in order to be able to suspend them in a rigid, i.e. non-deformable or axially non-displaceable eccentric ring, which is required by the prior art, is avoided by the present disclosure. The coupling of pump units 2 to the lubricant pump 100 is simplified.

LIST OF REFERENCE NUMERALS

[0068] 1 Pump housing [0069] 2 Pump unit [0070] 3 Pump drive [0071] 4 Coupling mechanism [0072] 5 Latching connection [0073] 6 Guide element [0074] 7 Screw connection [0075] 10 Receiving opening [0076] 12 Lubricant outlet opening [0077] 20 Delivery piston [0078] 21 Coupling section [0079] 22 Pump-side latching element [0080] 23 Circumferential projection [0081] 24 Circumferential groove [0082] 25 Suction opening [0083] 26 Outlet opening [0084] 27 End face [0085] 29 Pump cylinder [0086] 30 Drive shaft [0087] 31 Eccentric element, eccentric disc [0088] 32 Rolling bearing [0089] 33 Rolling bearing [0090] 34 Outer bearing ring [0091] 40 Outer bearing ring [0092] 41 Coupling section [0093] 42 Drive-side latching element [0094] 43 Carrier element [0095] 44 Displacement guide [0096] 45 Guide element [0097] 46 Latching projection [0098] 47 Spring guide opening [0099] 48 Latching block [0100] 49 Sliding surface [0101] 50 Spring element [0102] 51 Stop surface [0103] 52 Stop surface [0104] 53 Through opening [0105] 61 Latching surface [0106] 62 Beveled surface section [0107] 63 Guide surface [0108] 71 Latching surface [0109] 72 Beveled surface section [0110] 73 Guide surface [0111] 100 Lubricant pump [0112] A Longitudinal axis [0113] R Radial direction