AXIAL SECURING OF A PUMP

Abstract

A pump includes a pump housing including an inlet for the fluid on a low-pressure side, an outlet for the fluid on a high-pressure side, a circumferential wall facing faces axially away from the delivery chamber and on which the outlet emerges; a spring structure arranged on the outer end face of the end wall; a delivery member movable within the delivery chamber for delivering the fluid from the low-pressure side to the high-pressure side; and a securing device for axial securing the pump housing. The securing device includes a female holding element having an axially extending cavity and a male holding element in a joining engagement, exposable to an axial tensile load, with the female holding element in the cavity. The spring structure and/or the end wall is/are held on the pump housing by one of the holding elements by the joining engagement.

Claims

1. A pump for supplying fluid to a unit, the pump comprising: 1.1. a pump housing comprising: an inlet for the fluid on a low-pressure side, an outlet for the fluid on a high-pressure side, a circumferential wall which radially surrounds a delivery chamber, and an end wall having an outer end face which faces axially away from the delivery chamber and on which the outlet emerges; 1.2. a spring structure which is arranged on the outer end face of the end wall; 1.3. a delivery member which can be moved within the delivery chamber for delivering the fluid from the low-pressure side to the high-pressure side; and 1.4. a securing device for axial securing the pump housing, the securing device comprising: a female holding element having an axially extending cavity, and a male holding element which is in a joining engagement, which can be exposed to an axial tensile load, with the female holding element in the cavity; 1.5. wherein the spring structure and/or the end wall is/are held on the pump housing by one of the holding elements by way of the joining engagement; and 1.6. the securing device is not in an axial sealing contact with a connecting wall of an accommodating device when the pump is installed.

2. The pump according to claim 1, wherein the securing device furthermore comprises an additional holding element and the additional holding element overlaps with the end wall in an axial view and holds the pump housing axially together.

3. The pump according to claim 1, wherein an outer end face of the spring structure and/or end wall which faces axially away from the delivery chamber is in axial contact with one of the holding elements, whereby the spring structure and/or end wall is/are held on the pump housing.

4. The pump according to claim 1, wherein the securing device furthermore comprises an additional holding element, which is formed separately from the female holding element and the male holding element and is held by way of the joining engagement between the holding elements.

5. The pump according to claim 1, wherein the securing device furthermore comprises an additional holding element and the additional holding element is formed by a plate or a flat cup which is concave or convex in relation to the pump housing.

6. The pump according to claim 1, wherein the securing device furthermore comprises an additional holding element and the additional holding element additionally encompasses the function of a throttle and/or cold start plate.

7. The pump according to claim 1, wherein the securing device furthermore comprises an additional holding element and the additional holding element overlaps with the spring structure in an axial view onto the spring structure and holds the spring structure on the pump housing.

8. The pump according to claim 1, wherein the securing device furthermore comprises an additional holding element and the additional holding element comprises at least one radially protruding tongue which overlaps with the spring structure in an axial view onto the spring structure and holds the spring structure on the pump housing.

9. The pump according to claim 1, wherein the securing device furthermore comprises an additional holding element and the female holding element or the male holding element is in axial contact with a rear side of the additional holding element which faces axially away from the pump housing and presses the additional holding element against the spring structure and/or against the end wall.

10. The pump according to claim 1, wherein the securing device furthermore comprises an additional holding element and, when the pump is installed, the additional holding element is exclusively in contact with the female holding element and/or the male holding element and/or the spring structure and/or the end wall.

11. The pump according to claim 1, wherein the spring structure is in a sealing contact with the end wall and/or the connecting wall of the accommodating device when the pump is installed.

12. The pump according to claim 1, wherein the female holding element or the male holding element protrudes axially from or through the circumferential wall into or through the end wall.

13. The pump according to claim 1, wherein the female holding element and/or the male holding element is/are arranged on the high-pressure side of the pump.

14. The pump according to claim 1, wherein the spring structure surrounds the female holding element and/or the male holding element in the radial direction.

15. The pump according to claim 1, wherein the female holding element and the male holding element are in joining engagement via a screwing connection.

16. The pump according to claim 1, wherein the female holding element and the male holding element are formed by standard parts comprising metric threads.

17. The pump according to claim 1, wherein the securing device furthermore comprises an additional holding element.

18. The pump according to claim 4, wherein the female holding element and/or the male holding element protrude(s) through the additional holding element.

19. The pump according to claim 5, wherein the additional holding element is perforated and/or comprises one layer and/or is circular.

20. The pump according to claim 16, wherein the female holding element is a standard pin comprising an internal thread and the male holding element is a matching machine screw.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0073] The invention is explained below on the basis of example embodiments. Features disclosed by the example embodiments advantageously develop the subject-matter of the claims and also the embodiments explained above. There is shown:

[0074] FIG. 1 an isometric view of a pump of a first example embodiment;

[0075] FIG. 2 an isometric view of a pump of a second example embodiment;

[0076] FIG. 3 the pump of the first example embodiment in a longitudinal section;

[0077] FIG. 4 a detailed view of the joining engagement of the first example embodiment;

[0078] FIG. 5 a longitudinal section of the pump of the first embodiment, when installed;

[0079] FIG. 6 a schematic view of a joining engagement of a third example embodiment;

[0080] FIG. 7 a schematic view of a joining engagement of a fourth example embodiment; and

[0081] FIG. 8 a schematic view of a joining engagement of a fifth example embodiment.

DETAILED DESCRIPTION OF THE INVENTION

[0082] FIG. 1 discloses a pump of a first example embodiment, in an isometric view. FIG. 3 discloses a longitudinal section of the pump in accordance with the first example embodiment. The pump comprises a pump housing 10 featuring a circumferential wall 12, a first end wall 11 and a second end wall 13. An assembly structure is formed on the second end wall 13, using which the pump can be fixed to an accommodating device, for example by means of screws. The first end wall 11 is formed on the side of the circumferential wall 12 which faces away from the assembly structure. The circumferential wall 12, the first end wall 11 and the second end wall 13 are formed as separate components. In alternative embodiments, the circumferential wall 12 can for example be embodied in one piece with the second end wall 13 or the first end wall 11.

[0083] The circumferential wall 12 surrounds a delivery chamber in the radial direction, in which a delivery member 17, 18 for delivering the fluid from a low-pressure side of the pump to a high-pressure side of the pump is situated. The delivery chamber is delineated in the axial direction by the first end wall 11 and the second end wall 13.

[0084] The delivery member 17, 18 is preferably formed by a rotating delivery rotor 18 which is non-rotatably connected to a drive shaft 17 which drives it. FIG. 3 is a longitudinal section through the pump. The drive shaft 17 protrudes through the second end wall 13 in the axial direction. The rotor 18 is non-rotatably connected to the drive shaft 17, such that rotating the drive shaft 17 about the rotational axis R rotates the rotor 18 about the rotational axis R.

[0085] The delivery rotor 18 is preferably formed by a rotor of a vane pump comprising at least one vane. It should be noted that an aspect of the invention is not restricted to vane pumps. An aspect of the invention can for example also be used in pendulum-slider pumps, external gear pumps or internal gear pumps.

[0086] The circumferential wall 12 forms a closed ring, while the end walls 11 and 13 are each embodied to be plate-shaped. An outlet for the fluid emerges on the end wall 11 on the outer end face which faces axially away from the delivery chamber. The pump in accordance with the first example embodiment is embodied as a mono-flux pump, i.e. it comprises one working flux comprising an inlet and an outlet. It should be noted at this juncture that an aspect of the invention is not limited to mono-flux pumps and can also for example be used in multi-flux or multi-circuit pumps, in particular dual-flux pumps, comprising multiple outlets and/or inlets.

[0087] The pump housing 10 is secured in the axial direction by a securing device 20. The securing device 20 in accordance with the first example embodiment comprises: a female holding element 21 featuring an axially extending cavity 22; a male holding element 23 which is in a joining engagement, which can be exposed to an axial tensile load, with the female holding element 21 in the cavity 22; and an additional holding element 24.

[0088] The spring structure 14 is arranged axially between the first end wall 11 and the additional holding element 24. The additional holding element 24 overlaps the spring structure 14 in a radially inner region of the spring structure 14 in an axial view onto the first end wall 11; preferably, the tongues 25 of the additional holding element 24 overlap the spring structure 14. The additional holding element 24 engages behind the spring structure 14 in an axial view from the first end wall 11 towards the spring structure 14; preferably, the tongues 25 of the additional holding element 24 engage behind the spring structure 14. In this way, the spring structure 14 is held on the pump housing 10 by means of the additional holding element 24. The spring structure 14 which is formed as a mechanical spring, and in the example embodiment as a disc spring, serves to press the housing walls 11, 12 and 13 of the pump housing 1 axially together when the pump is assembled and so seal off the delivery chamber.

[0089] The securing device 20 serves in particular to axially secure the spring structure 14 on the pump housing 10 and to axially secure the pump housing 10. In particular, the female holding element 21, the male holding element 23 and the additional holding element 24 serve to secure the spring structure 14 on the pump housing 10 and to axially secure the pump housing 10. In alternative embodiments, in particular embodiments with no spring structure, the securing device can axially secure the end wall 11, instead of the spring structure 14, on the pump housing.

[0090] The additional holding element 24 is a holding element which is separate from the male holding element 23 and the female holding element 21. In alternative embodiments, the additional holding element 24 can also be embodied in one piece with the female holding element 21 or with the male holding element 23 and in particular formed by the female holding element 21 or the male holding element 23, as disclosed in FIGS. 6 and 7.

[0091] As can be seen in particular from FIG. 3, the additional holding element 24 is held on the pump housing 10 by way of the joining engagement between the male holding element 23 and the female holding element 21. The additional holding element 24 is formed on the side of the first end wall 11 of the pump housing 10. The additional holding element 24 is in particular formed on the side of the pump housing 10 which faces axially away from the second end wall 13.

[0092] The outer circumference of the additional holding element 24 comprises at least one tongue 25 which protrudes radially outwards. In particular, the additional holding element 24 comprises four tongues 25 which protrude radially outwards from the additional holding element 24. In accordance with the first example embodiment, the tongues 25 are distributed uniformly over the outer circumference of the additional holding element 24.

[0093] The tongues 25 overlap the spring structure 14 in an axial view onto the end wall 11. The spring structure 14 is in axial contact with the additional holding element 24, in particular with the tongues 25 of the additional holding element 24, on a rear side which faces axially away from the pump housing 10, whereby it is held on the pump housing 10. The additional holding element 24 presses the spring structure 14 against the pump housing 10, in particular against the first end wall 11, in the axial direction. The additional holding element 24 also presses the end wall 11 against the pump housing 10, in particular against the circumferential wall 12.

[0094] The additional holding element 24 comprises at least one passage through which the female holding element 21 or the male holding element 23 axially protrudes. In accordance with the first example embodiment, the male holding element 23 protrudes through the passage of the additional holding element 24 in the axial direction. In accordance with the first example embodiment, the additional holding element 24 comprises a total of two passages for a male holding element 23 each. The passages are each formed in the region of a tongue 25 on the outer edge of the additional holding element 24. In accordance with the first example embodiment, a male holding element 23 respectively protrudes through the additional holding element 24 in the axial direction, counter to the first end wall 11.

[0095] The additional holding element 24 is in axial contact with a part of the male holding element 23 on a rear side which faces axially away from the pump housing 10 and is pressed against the spring structure 14 in the axial direction. The additional holding element 24 in turn presses the spring structure 14 against the pump housing 10, in particular against the first end wall 11, in the axial direction, thus holding the end wall 11 on the pump housing 10. As can be seen in particular from FIG. 3, the additional holding element 24 is in axial contact with the spring structure 14 and the first end wall 11 on its front side which axially faces the pump. In this way, the additional holding element 24 presses the spring structure 14 against the first end wall 11 in the axial direction and presses the first end wall 11 towards the second end wall 13 in the axial direction. In this way, the pump housing 10 is held together in the axial direction.

[0096] The male holding element 23 protrudes at least partially into the cavity 22 of the female holding element 21 and forms a joining engagement, which can be exposed to an axial tensile load, with the female holding element 21. The joining engagement between the male holding element 23 and the female holding element 21 is embodied such that it can be released again and is formed in accordance with the first example embodiment in the form of a screw connection.

[0097] The male holding element 23 closes the cavity 22 of the female holding element 21. Because the male holding element 23 closes the cavity 22 of the female holding element 21, the abrasion caused by the relative movement between the female holding element 21 and the male holding element 23 during assembly is pressed into the cavity 22 and enclosed in it.

[0098] The additional holding element 24 is embodied in the form of a perforated plate which overlaps, in particular completely, with the outlet of the pump housing 10 in the axial direction. In this way, the additional holding element 24 additionally assumes a throttling function.

[0099] The female holding element 21 is formed on the front side of the additional holding element 24 which faces the pump housing 10. The female holding element 21 is embodied in the form of a holder and is a constituent part of the pump housing 10 and positions the circumferential wall 12 and the end wall 11 relative to each other in terms of their angular position, wherein the cavity of the female holding element 21 is provided on the end side of the female holding element 21 which faces the spring structure 14.

[0100] In accordance with the first example embodiment, the female holding element 21 protrudes from the circumferential wall 12 and through the first end wall 11. In particular, the female holding element 21 protrudes from the second end wall 13 in the axial direction through the circumferential wall 12 and through the first end wall 11. In this way, the female holding element 21 positions the first end wall 11 and the second end wall 13 in terms of their rotational angular position relative to the circumferential wall 12 and holds them together.

[0101] In accordance with the first example embodiment, the female holding element 21 is embodied in the form of a standard part, in particular a standard pin comprising an internal thread. The male holding element 23 is correspondingly formed by a standardised screw which is in joining engagement with the internal thread of the female holding element 21.

[0102] FIG. 4 shows the screw engagement between the male holding element 23 and the female holding element 21 in detail, wherein the shaft of the male holding element 23 protrudes axially through a passage of the additional holding element 24 and protrudes into the cavity 22 of the female holding element 21. The passage of the additional holding element 24 is provided on a radially outer edge of the additional holding element 24 and can in particular be formed in the region of the tongues 25.

[0103] The head of the male holding element 23 presses axially against the additional holding element 24 such that the additional holding element 24 is in axial contact with the male holding element 23 on a rear side which faces axially away from the pump housing 10. The male holding element 23 axially tenses the additional holding element 24 against the pump housing 10. In alternative embodiments, the additional holding element 24 can be omitted, such that the head of the male holding element 23 presses axially against the end wall 11, such that the end wall 11 is held on the pump housing 10.

[0104] The joining engagement is embodied radially within the spring structure 14 in an axial view onto the spring structure 14. The joining engagement is in particular embodied within the sealing contact with the first end wall 11 on the one hand and the connecting wall of the accommodating device, which lies axially opposite when the pump is installed and is not shown in FIGS. 1, 3 and 4, on the other hand in an axial view onto the spring structure 14, wherein the joining engagement is provided in the region of the tongues 25 which protrude radially outwards.

[0105] FIG. 5 shows the pump of the first example embodiment, when installed. The pump is arranged on or in an accommodating device, wherein the first end wall 11 lies axially opposite a connecting wall of the accommodating device. A pressure port, which is not otherwise shown and via which the fluid flowing through the outlet can be discharged, emerges on the connecting wall of the accommodating device. The outlet of the pump axially faces the connecting wall of the accommodating device. The accommodating device is sealed off by a radial gasket 16 arranged on the pump housing 10.

[0106] The spring structure 14 is tensed between the connecting wall and the end face of the first end wall 11 which faces the connecting wall. In this way, the spring structure 14 is in axial contact with the first end wall 11 and with the connecting wall of the accommodating device. In particular, the spring structure 14 is in an axial sealing contact with the first end wall 11 and with the connecting wall, such that it additionally functions as an axial gasket which separates the high-pressure side from the low-pressure side. In addition to the spring structure 14, the pump comprises at least one other radial gasket 15 for separating the high-pressure side from the low-pressure side, preferably in the region of the outer circumference of the first end wall 11.

[0107] By contrast, the securing device 20 is not in axial contact with the connecting wall of the accommodating device. In accordance with an aspect of the invention, the securing device 20 is not in axial sealing contact, in particular pressure contact, with the connecting wall of the accommodating device. In particular, neither the male holding element 23 nor the additional holding element 24 and the female holding element 21 are in axial contact with the connecting wall of the accommodating device.

[0108] As can be seen from FIG. 5, the securing device 20 is embodied exclusively on the high-pressure side of the pump, i.e. only fluid discharged from the pump through the outlet flows around the securing device 20, in particular the additional holding element 24 and the male holding element 23, wherein the spring structure 14 surrounds the securing device 20 on the radially outer side, wherein the additional holding element 24 at least partially overlaps axially with the spring structure 14.

[0109] FIG. 2 shows an isometric view of a pump in accordance with a second example embodiment. Unless otherwise stated, the statements made with respect to the first example embodiment remain valid, providing they do not contradict the example embodiment in accordance with FIG. 2.

[0110] The pump of FIG. 2 differs from the pump of the first example embodiment in that the outer circumference of the additional holding element 34 does not comprise any tongues which protrude radially outwards, and in that the additional holding element 34 does not overlap with the spring structure 14 in an axial view onto the spring structure 14.

[0111] In accordance with the second example embodiment, the spring structure 14 is held on the pump housing 10 by the male holding element 23. The male holding element 23 is in axial contact with the additional holding element 34 on the rear side of the additional holding element 34 which faces axially away from the pump housing 10. In particular, the male holding element 23 presses the additional holding element 34 against the pump housing 10 in the axial direction.

[0112] Unlike the additional holding element 24 in accordance with the first example embodiment, the additional holding element 34 substantially has a throttling function only and does not secure the spring structure 14 in the axial direction. The additional holding element 34 can however additionally press the first end wall 11 towards the second end wall 13 in the axial direction and so help to secure the pump housing 10 in the axial direction.

[0113] The male holding element 23 is also in axial contact with the spring structure 14 on the rear side of the spring structure 14 which faces axially away from the pump housing 10. The male holding element 23 presses the spring structure 14 against the pump housing 10 in the axial direction. In alternative embodiments, the additional holding element 34 in accordance with the second example embodiment can also be omitted. In this case, the pump housing 10 is secured in the axial direction by the male holding element 23, the female holding element 21 and the spring structure 14. In alternative embodiments, the additional holding element 34 can in particular be omitted, such that the head of the male holding element 23 presses axially against the end wall 11 and/or the spring structure 14, such that the end wall 11 and/or the spring structure 14 are held on the pump housing 10.

[0114] FIGS. 6 to 8 schematically show other example embodiments of the joining engagement between a female holding element and a male holding element in each case. Features of the first example embodiment, in particular those relating to the spring structure 14 and the pump, also apply to the following example embodiments unless expressly stated otherwise. Wherever differences are not explained or disclosed on the basis of the figures, the statements made above with respect to the first and/or second example embodiment also similarly apply to the other example embodiments.

[0115] FIG. 6 shows a third example embodiment in which the male holding element 43 is formed by the additional holding element 44 and does not protrude through it, wherein the additional holding element 44, in particular the tongues 25, exhibit(s) a convex curvature or outward bulge which protrudes from the additional holding element 44 towards the first end wall 11 or female holding element 41. Instead of a curvature or outward bulge, the male holding element 43 of the additional holding element 44 can also be formed as a protruding pin, cam or the like.

[0116] The female holding element 41 in turn comprises a concave cavity 42 in relation to the first end wall 11, into which the male holding element 43 can protrude in order to establish a joining engagement, wherein the cavity 42 can be embodied directly on the first end wall 11 or on a separate component, for example a holder as shown in FIG. 3 and FIG. 5.

[0117] The cavity 42 of the female holding element 41 is embodied to be complementary to the outward bulge of the male holding element 43. The joining engagement between the male holding element 43 and the female holding element 41 is embodied as a fitting connection. The male holding element 43 has an oversize relative to the cavity 42 of the female holding element 41, such that the male holding element 43 can be pressed into the female holding element 41 and is held in the joining engagement, wherein the holding force with which the male holding element 43 is held in the joining engagement with the female holding element 41 is determined by the oversize of the male holding element 43.

[0118] FIG. 7 shows a joining engagement in a fourth example embodiment in which the female holding element 51 is formed by the additional holding element 54, wherein the additional holding element 54, for example the respective tongue 25, forms the female holding element 51 by comprising an outward bulge having a cavity 52 which extends in a direction away from the first end wall 11. The female holding element 51, i.e. the outward bulge, is open towards the end wall 11. The male holding element 53 protrudes from the first end wall 11 and, in the joining engagement, into the female holding element 51. This joining engagement is likewise a fitting connection. The male holding element 53 can be formed by the end wall 11 itself or by a separate component, for example a holder for the pump housing 10. The male holding element 53 can then be an axial projection on the end wall 11, i.e. formed directly on the end wall 11.

[0119] In order to form the joining engagement between the male holding element 53 and the female holding element 51, the female holding element 51 is fitted onto the male holding element 53. The male holding element 53 has an oversize relative to the cavity 52 of the female holding element 51, such that the male holding element 53 can be pressed into the female holding element 51 and is held in the joining engagement, wherein the holding force with which the male holding element 53 is held in the joining engagement with the female holding element 51 is determined by the oversize of the male holding element 53.

[0120] A fitting engagement is also understood to mean a snapping or latching engagement between the holding elements in the manner of a press-stud connection. It is in principle advantageous if the respective fitting engagement is configured such that the cavity 42 or 52 is closed by the male holding element 43 or 53 to such an extent that any dirt particles that can have entered the cavity 42 or 52 are enclosed and cannot be discharged while the pump is in operation.

[0121] FIG. 8 shows a fifth example embodiment of a joining engagement in which the male holding element 63 protrudes through a passage of the additional holding element 64 in a direction away from the first end wall 11. The male holding element 63 protrudes from the first end wall 11 and forms a joining engagement with the female holding element 61. The male holding element 63 can be formed by the end wall 11 itself or by a separate component. The male holding element 63 can then be an axial projection on the end wall 11, i.e. formed directly on the end wall 11.

[0122] The end of the male holding element 63 which faces axially away from the second end wall 13 comprises an external thread, in particular a metric external thread, wherein the male holding element 63 can comprise a thread in one axial end portion only or in both axial end portions or can be embodied as a threaded pin which comprises a thread over its entire axial length. In embodiments in which it is a threaded pin with a continuous thread over its axial length or in which it comprises a thread at its axial ends, the male holding element 63 is preferably in a screw engagement with both the female holding element 61 and the second end wall 13.

[0123] The female holding element 61 is form as a nut, in particular a cap nut. The female holding element 61 presses axially against the additional holding element 64 in the joining engagement with the male holding element 63, such that the additional holding element 64 is in axial contact with the female holding element 61 on a rear side which faces axially away from the pump housing 10, and thus holds the additional holding element 64 on the pump housing 10.

[0124] In modifications of the fifth example embodiment, the male holding element and the female holding element which is provided separately from the additional holding element can also be fitting elements for establishing a fitting engagement instead of a screwing engagement.

[0125] In other modifications, holding elements in the form of screw elements, such as for example threaded pins and/or nuts, can be fixedly joined to the additional holding element and preferably arranged on the tongues 25. In such embodiments, the respective complementary screw element is axially fixed on the pump housing 10, but rotatably connected to the pump housing 10 in order to be able to establish the joining engagement as a screwing engagement.

LIST OF REFERENCE SIGNS

[0126] 10 pump housing [0127] 11 first end wall [0128] 12 circumferential wall [0129] 13 second end wall [0130] 14 spring structure [0131] 15 radial gasket [0132] 16 radial gasket [0133] 17 drive shaft [0134] 18 rotor [0135] 20 securing device [0136] 21 female holding element [0137] 22 cavity [0138] 23 male holding element [0139] 24 additional holding element [0140] 25 tongue [0141] 34 additional holding element [0142] 41 female holding element [0143] 42 cavity [0144] 43 male holding element [0145] 44 additional holding element [0146] 51 female holding element [0147] 52 cavity [0148] 53 male holding element [0149] 54 additional holding element [0150] 61 female holding element [0151] 62 cavity [0152] 63 male holding element [0153] 64 additional holding element