DE102017214264A1 - PUMP HOUSING FOR A GEROTOR PUMP AND GEROTOR PUMP - Google Patents

Abstract

The present invention relates to a pump housing for a gerotor pump, having a bottom and a lid, with a arranged between the bottom and cover receiving space, which is adapted to receive an inner rotor and an outer rotor, with a first fluid port and a second Fluid port, wherein the first fluid port has a first disposed at the bottom opening in the receiving space and a second disposed on the lid opening in the receiving space, and wherein the pump housing has at least one channel directly connecting the first opening and the second opening with each other. The present invention further relates to a gerotor pump, in particular with such a pump housing.

Description

FIELD OF THE INVENTION

The present invention relates to a pump housing for a gerotor pump and a gerotor pump, in particular for the automotive sector.

TECHNICAL BACKGROUND

Gerotor pumps, which are also referred to as G-rotor pump, rotor pump, ring gear pump or Eaton pump, represent a special type of so-called gear pumps. Gear pumps have in principle three components, namely a housing with inlet and outlet as well two gears or rotors.

The peculiarity of the gerotor pump is that a running in a pump housing internally toothed outer rotor and an inner externally toothed rotor are provided, which each have only a few teeth and manage without additional components within the pump housing. In contrast to so-called sickle pumps, also referred to as internal gear pumps, which have relatively large diameter differences of the gears and a fluid flow in a separation region of the gears separating sickle in the pump housing, has an inner rotor of a gerotor pump usually only one tooth less than an outer Rotor on. Due to the toothing, a number of gerotor cells corresponding to the number of valleys of the internal teeth of the outer rotor are always formed between the inner and outer rotors, which each have different volumes at a particular point in time. The cells grow and shrink periodically during rotation, creating a negative pressure on the suction side and an overpressure on the pressure side.

Gerotor pumps are often used in the automotive industry for oil or fuel production. By way of example, such a gerotor oil pump in the DE 10 2015 002 353 A1 described. Such gerotor pumps have axial offset to the rotors usually formed in a housing cover and / or housing bottom suction and pressure openings, which are formed with a kidney-shaped groove for pressure distribution on the suction side and on the pressure side, also called Saugniere and Druckniere. These grooves connect each of the suction side and pressure side gerotor cells with each other to create a certain pressure equalization of the cells with each other on each side.

Such pumps are usually designed thermodynamically such that they operate cavitation-free, that is, without blistering by outgassing (cavitation) of the fluid to be delivered, which can be caused by an excessive negative pressure on the suction side. A reduction in the cavitation tendency can be achieved on the one hand by a streamlined design of the intake area or on the other hand by sufficiently large Ansaugquerschnitte.

In order to achieve an enlarged intake cross section of a gerotor pump, an inlet, a so-called dual inlet, can be provided on both sides of the rotors. Such a gerotor pump with dual inlet is for example in the WO 2006/136014 A1 described. A pump housing has for this purpose two separate fluid ports, which each lead to a separate inlet on different sides of the rotors.

SUMMARY OF THE INVENTION

Against this background, the present invention seeks to provide an improved pump housing for a gerotor pump and an improved gerotor pump.

According to the invention, this object is achieved by a pump housing having the features of patent claim 1 and / or by a gerotor pump having the features of patent claim 8.

• - Ein Pumpengehäuse für eine Gerotor-Pumpe, mit einem Boden und mit einem Deckel, mit einem zwischen dem Boden und dem Deckel angeordneten Aufnahmeraum, der zur Aufnahme eines inneren Rotors und eines äußeren Rotors ausgebildet ist, mit einem ersten Fluidanschluss und mit einem zweiten Fluidanschluss, wobei der erste Fluidanschluss eine erste an dem Boden angeordnete Öffnung in den Aufnahmeraum und eine zweite an dem Deckel angeordnete Öffnung in den Aufnahmeraum aufweist, und wobei das Pumpengehäuse zumindest einen Kanal aufweist, der die erste Öffnung und die zweite Öffnung direkt miteinander verbindet.
• - Eine Gerotor-Pumpe, insbesondere für den Automobilbereich, mit einem inneren Rotor und einem äußeren Rotor, mit einem den äußeren Rotor umfänglich umgebenden Pumpengehäuse, insbesondere einem erfindungsgemäßen Pumpengehäuse, welches einen Boden und einen Deckel aufweist, wobei das Pumpengehäuse einen ersten saugseitigen Fluidanschluss und einen zweiten druckseitigen Fluidanschluss aufweist, wobei der erste Fluidanschluss eine als Einlass vorgesehene erste Öffnung an dem Boden und eine als Einlass vorgesehene zweite Öffnung an dem Deckel aufweist, und wobei das Pumpengehäuse zumindest einen Kanal aufweist, der die erste Öffnung und die zweite Öffnung direkt miteinander verbindet.

Accordingly, it is provided:

• - A pump housing for a gerotor pump, having a bottom and a lid, with a disposed between the bottom and the lid receiving space, which is adapted to receive an inner rotor and an outer rotor, having a first fluid port and a second fluid port wherein the first fluid port has a first opening disposed at the bottom in the receiving space and a second opening disposed at the lid in the receiving space, and wherein the pump housing has at least one channel directly connecting the first opening and the second opening.
• - A gerotor pump, in particular for the automotive sector, with an inner rotor and an outer rotor, with a circumferentially surrounding the outer rotor pump housing, in particular a pump housing according to the invention, which has a bottom and a lid, wherein the pump housing has a first suction-side fluid port and a second pressure-side fluid port, wherein the first fluid port has a first opening at the bottom and an inlet provided as an inlet second opening on the lid, and wherein the pump housing has at least one channel directly connecting the first opening and the second opening with each other.

The idea on which the present invention is based is to design a pump housing for or in a gerotor pump in such a way that two inlets in the form of openings of a fluid connection and a channel directly connecting the two openings each forming an inlet are provided for axially supplying the rotors on both sides are provided to connect the two openings in the operation of a gerotor pump with each other directly fluidly.

Preferably, the channel is provided directly on an inner circumference of the pump housing and can thus pass on the bottom and on the lid directly into the, usually designed as a kidney-shaped groove, provided as an inlet openings.

Advantageously, on the one hand, only one common suction-side fluid connection needs to be provided in the pump housing. On the other hand, a direct pressure equalization between the two openings on the suction side can take place particularly advantageously, so that any negative pressure peaks occurring at one of the two openings can be dissipated via the other opening and a cavitation tendency as a whole is thus reduced. Thus, the pump efficiency is improved and avoided unwanted noise and unwanted wear. In other words, the suction chambers or intake cross sections of a dual inlet are thus fluidly coupled with each other directly.

The at least one channel may be one or more channels. Furthermore, a division of a channel into several sub-branches is possible.

In principle, it would also be conceivable to provide at least one such channel on the outlet side for connecting openings formed as an outlet. The pump housing according to the invention is also suitable for this purpose. For example, can be exchanged by reversing the direction of rotation suction and pressure side. Preferably, however, only such a channel is provided on either the inlet or the outlet side to avoid fluidic shorting over chamfers usually provided at the outer edges of the outer rotor. If, however, an additional seal or a negligibility of a possible short circuit is created here, it would also be conceivable to provide at least one channel according to the invention both on the suction side and on the pressure side.

Advantageous embodiments and further developments will become apparent from the other dependent claims and from the description with reference to the figures of the drawing.

According to a preferred embodiment, the receiving space of the pump housing is formed with an extending from the bottom, in particular circular or kreiszylindermantelförmigen, inner circumferential surface. This inner circumferential surface is designed for the positive reception of an outer rotor. In particular, when the outer rotor is an external rotor, i. a not directly driven outer rotor, is its outer peripheral surface is also circular. Accordingly, a suitable fit between the outer rotor and the inner peripheral surface of the pump housing is provided to provide sufficient tightness between the outer rotor and the pump housing and still allow a low-loss rotatability of the outer rotor in the pump housing. For example, a friction-reducing surface finish and / or coating may be provided on the outer circumferential surface of the outer rotor and / or on the inner circumferential surface of the pump housing.

According to a preferred embodiment, the at least one channel extends on the inner peripheral surface. For example, the at least one channel is formed as a recess on the inner peripheral surface. Advantageously, in this way only a minimal space is required to provide the at least one channel. In particular, a conventional pump housing, apart from the introduction of the at least one channel, remain unchanged in terms of its dimensions.

In a further embodiment, it would also be conceivable to provide a channel as a bore running away from the inner peripheral surface in the pump housing. For this purpose, however, in particular an additional space or a larger dimensions of the pump housing would be necessary.

According to a preferred embodiment, the at least one channel is formed as an axial groove. Preferably, it is a running on the inner peripheral surface of the pump housing axial groove. In this way, a direct connection between the two openings is created on the shortest path. The groove may have a wide variety of cross-sectional areas, such as rectangular, circular segment or semicircular, triangular, polygonal or the like.

According to an advantageous embodiment, the first opening and the second opening are connected via at least two channels. Especially For example, the first and second openings may be connected via three channels. Also more than three channels are possible. Due to the division into two, three or possibly more channels provided by the inner peripheral surface of the pump housing bearing surface for the outer rotor is advantageously not interrupted locally too strong, so that despite the channels, the mechanical stability of the pump housing is ensured during operation of a gerotor pump.

According to a development, the channels have the same cross-section. In this way, a uniform pressure distribution takes place along the first and second openings, especially if they are in the form of kidney-shaped openings, i. as so-called suction kidneys, formed and the channels are distributed along the kidney shape. In further embodiments, the cross sections of the channels may also be designed differently or differently, for example in a manner adapted to the respective position of the channels on the suction kidney and / or flow-optimized manner.

According to an advantageous development, a support surface is provided on each of the channels on the inner circumferential surface for the radial support of an outer rotor which can be accommodated in the pump housing. Thus, supports for an outer rotor are provided between the channels, so that a high mechanical stability of the bearing of the outer rotor is ensured during operation of a gerotor pump.

According to one embodiment of a gerotor pump, the at least one channel is formed with a groove which is closed at its open longitudinal side between the first opening and the second opening by an outer peripheral surface of the outer rotor. It is thus advantageous to a closed during operation channel, which is provided but only by introducing a groove on an inner circumferential surface of the pump housing and thus very simple and in particular without additional space can be produced.

According to one embodiment, the second fluid connection has at least one third opening provided as an outlet on the lid and / or on the bottom. This third opening may also be in the form of a kidney-shaped recess or groove, i. be designed as a so-called pressure kidney. Advantageously, pressure equalization between the gerotor cells is thus also provided on the pressure side. It is also conceivable to provide such a third opening both on the cover and on the bottom so as to reduce flow resistances at the outlet and / or to improve pressure equalization between the pressure-side gerotor cells.

According to an advantageous embodiment of the outer rotor is positively received in the pump housing so that the at least one third opening relative to the first and second opening by the positive connection of the outer rotor with the pump housing, at least substantially sealed. In particular, when the outer rotor is a rotor, i. a not directly driven but only driven via the inner rotor outer rotor is, its outer peripheral surface and also the inner peripheral surface of the pump housing are circular (or cylinder cylinder shell-shaped). Accordingly, a suitable fit is provided between the outer rotor and the inner peripheral surface of the pump housing to provide sufficient sealing between the outer rotor and the pump housing, but the rotor in the pump housing, of course, remains rotatable. For example, this can be realized by adjusting a fit such that there is a controlled oil film formed upon rotation and delivery of oil between the outer peripheral surface of the rotor and the inner peripheral surface of the pump housing. A tightness is thus preferably given in the operation of the gerotor pump and not necessarily absolutely, but substantially, i. provided in a sufficiently practical tightly sealed, in order to avoid a noticeable fluidic short circuit between the first and second fluid connection.

The above embodiments and developments can, if appropriate, combine with each other as desired. In particular, all the features of a pump housing according to the invention can be transferred to a gerotor pump according to the invention and, if appropriate, vice versa. Further possible refinements, developments and implementations of the invention also include combinations, not explicitly mentioned, of features of the invention described above or below with regard to the exemplary embodiments. In particular, the person skilled in the art will also add individual aspects as improvements or additions to the respective basic form of the present invention.

list of figures

• 1 eine perspektivische Ansicht eines Pumpengehäuses;
• 2 eine Schnittansicht einer Gerotor-Pumpe mit einem Pumpengehäuse gemäß 1;
• 3 eine schematische Schnittansicht eines Pumpengehäuses gemäß einer weiteren Ausführungsform;
• 4 eine Schnittansicht einer Gerotor-Pumpe mit einem Pumpengehäuse gemäß 3;
• 5 eine schematische Schnittansicht eines Pumpengehäuses gemäß einer noch weiteren Ausführungsform; und
• 6 eine Schnittansicht einer Gerotor-Pumpe mit einem Pumpengehäuse gemäß 5.

The present invention will be explained in more detail with reference to the exemplary embodiments indicated in the schematic figures of the drawing. It shows:

• 1 a perspective view of a pump housing;
• 2 a sectional view of a gerotor pump with a pump housing according to 1 ;
• 3 a schematic sectional view of a pump housing according to a further embodiment;
• 4 a sectional view of a gerotor pump with a pump housing according to 3 ;
• 5 a schematic sectional view of a pump housing according to a still further embodiment; and
• 6 a sectional view of a gerotor pump with a pump housing according to 5 ,

The accompanying figures of the drawing are intended to convey a further understanding of the embodiments of the invention. They illustrate embodiments and, together with the description, serve to explain principles and concepts of the invention. Other embodiments and many of the stated advantages will become apparent with reference to the drawings. The elements of the drawings are not necessarily shown to scale to each other.

In the figures of the drawing are the same, functionally identical and same-acting elements, features and components - unless otherwise stated - each provided with the same reference numerals.

DESCRIPTION OF EMBODIMENTS

1 shows a perspective view of a pump housing 4 ,

The pump housing 4 is for a gerotor pump 1 provided, which is intended for use in the automotive or automotive sector, preferably as an oil pump.

The pump housing 4 is in 1 with a cup-shaped basic body shown on the right 15 , the one floor 5 has, and a lid shown on the left 6 educated. The lid 6 is shown here in disassembled and left unfolded state.

In an assembled state, the end faces are here oriented out of the plane of the drawing 16 of the lid 6 and 17 of the basic body 15 thus, if necessary. With a seal provided therebetween on each other. Further, the lid 6 is on the body 15 with through the illustrated mounting holes 18 . 19 guided fastened or screwed therein fasteners not shown here.

In a mounted state between the ground 5 and the lid 6 arranged recording room 23 is an inner rotor 2 and an outer rotor 3 received. The recording room 23 is accordingly one with one from the ground 5 extending circular inner peripheral surface 12 formed, in which an outer rotor 3 when installing a Gerotor pump 1 is recorded positively.

The pump housing 4 has a first fluid port 7 and a second fluid port 8th on. The fluid connections 7 . 8th For example, are designed as a nozzle for connecting an oil hose.

The first fluid connection 7 is provided as a suction-side connection and has a first opening 9 in the recording room 23 on which at the bottom 5 is arranged. Furthermore, the first fluid connection 7 on the same side of the pump housing, a second on the lid 6 arranged opening 10 in the recording room 23 on. The first and second openings 9 . 10 are thus each as an inlet to the recording room 23 intended. They are also each kidney-shaped and one in the pump housing 4 provided channel 11 directly connected.

In the embodiment shown here, by way of example, three are the openings 9 . 10 connecting channels 11 provided, which on the inner peripheral surface 12 of the pump housing 4 run and each formed as an axial groove. The channels 11 each have a same cross section.

Between the channels 11 is each a support surface 20 on the inner peripheral surface 12 intended. This serves for the radial support of one in the pump housing 4 receivable outer rotor 3 ,

In addition, the second fluid port 8th a third opening 14 in the recording room 23 on which on the lid 6 is provided. This is also kidney-shaped and provided as an outlet. Further, at the bottom 5 another kidney-shaped opening 22 provided in the form of a recess or pocket, although also the second fluid port 8th is assigned, but unlike the first fluid connection 7 not directly with the on the lid 6 arranged third opening 14 connected is. Accordingly, in this exemplary embodiment, at the side of the third opening 14 , ie on the pressure side, no additional channels provided.

The further kidney-shaped opening 22 For example, for additional pressure equalization at the outlet between those at the side of the third opening 14 be provided lying gerotor cells.

2 shows a sectional view of a gerotor pump 1 with a pump housing according to 1 ,

The gerotor pump 1 points next to the pump housing 4 an inner rotor formed with an internal toothing 2 and an external rotor formed with external teeth 3 on.

The inner rotor 2 is inside the internal teeth of the outer rotor 3 arranged eccentrically thereto and with a shaft-hub connection to a drive shaft 21 placed. For example, the drive shaft with a at the back of the floor 5 be coupled flanged electric motor.

The outer rotor 3 is here as of the inner rotor 2 driven rotor trained. He is with his outer peripheral surface 13 positively in the pump housing 4 , ie at its inner peripheral surface 12 , added. In this way, each formed with a groove channels 11 between the first opening 9 and the second opening 10 through the outer circumference 13 the outer rotor 3 closed.

If the inner rotor 2 and thus also the outer rotor 3 Turn clockwise in the illustrated perspective, it is at the first fluid port 7 around the suction-side fluid connection 7 and at the second fluid port 8th the pressure side fluid port, as with respect to the pump housing 4 already explained.

The first suction-side fluid connection therefore has a first opening provided as an inlet 9 on the ground 5 and a second opening provided as an inlet 10 on the lid 6 on. Thus, a dual inlet is provided, with both openings 9 . 10 through the channels 11 fluidly coupled directly to each other. Thus, the channels allow 11 an increase in the inlet cross section and a pressure equalization between the openings 9 . 10 ,

The third opening 14 of the second fluid port 8th forms an outlet opening accordingly. In addition, the third opening 14 by the positive connection with respect to the first and second openings 9 . 10 sealed in a fluidic short circuit avoiding manner

3 shows a schematic sectional view of a pump housing according to another embodiment.

Due to the illustrated perspective of the section is here schematically only one body 15 a pump housing 4 shown. fluid connections 7 . 8th are here for clarity, therefore, only through the openings 9 . 22 shown.

Qualitatively, this is a to the embodiment according to 1 similar pump housing 4 , unlike 1 but not three rectangular but only two semicircular on the inner peripheral surface 12 of the pump housing 4 introduced grooves as channels 11 are provided. A radial support surface 20 for the outer rotor 3 is thus formed significantly larger. Further, a kidney-shaped opening 9 with the channels 11 connecting recess in the ground 5 to the opening 9 fanned out to a pressure equalization between the two openings 9 . 10 to reach along the entire kidney shape. In the same way is also a fanned out connection to the opening 10 in the lid, not shown 6 intended.

4 shows a sectional view of a gerotor pump 1 with a pump housing 4 according to 3 ,

In the same way as in relation to 2 described is the outer rotor 3 with its outer peripheral surface 13 also here on the inner peripheral surface 12 of the pump housing 4 at. The eccentric arrangement of the inner rotor 2 to the outer rotor 3 but here is differently oriented. This has the consequence that here with a rotation of the rotors 2 . 3 counterclockwise the first fluid port 7 located on the suction side and thus the openings 9 . 10 of the first fluid port 7 act as a dual inlet. To illustrate, a dividing line between the suction and pressure side is shown schematically.

5 shows a schematic sectional view of a pump housing according to yet another embodiment. 6 shows a sectional view of a corresponding gerotor pump with such a pump housing according to 5 ,

This embodiment is based essentially on the embodiment of FIG 3 and 4 , in contrast, the channels 11 here from the inner peripheral surface 12 of the pump housing 4 are spaced.

Exemplary are the channels 11 here as in the pump housing 4 provided holes designed. The inner peripheral surface 12 of the pump housing 4 thus remains uninterrupted. However, the holes also require slightly more space compared to grooves. A basic body 15 of the pump housing 4 is therefore slightly larger in this embodiment, here exemplified wider, trained.

Although the present invention with reference to preferred embodiments above is fully described, it is not limited thereto, but modifiable in many ways.

In particular, the applicability of the gerotor pump according to the invention is not limited to the automotive sector. Rather, such a gerotor pump can also be used in other technical fields in which fluids, in particular oils, are conveyed under pressure.

For example, further alternatively or in addition to a channel could 11 on the inlet side basically also a channel 11 ' for connecting openings formed as an outlet 14 . 22 be seen. Preferably, in order to avoid a fluidic short circuit via chamfers, which are usually provided on the outer edges of the outer rotor, only such a channel is formed on either the inlet or the outlet side 11 intended. However, if additional measures for sealing are created, it would also be conceivable both at the suction and at the pressure side at least one of the respective openings 9 . 10 ; 14 . 22 connecting channel 11 . 11 ' provided. On the outlet side, if appropriate, the flow resistance could thus be reduced, thus increasing the overall efficiency of the pump. This can be advantageous if on the outlet side, for example on subsequent components, there are no subsequent narrower cross sections.

LIST OF REFERENCE NUMBERS

1

Gerotor pump

2

inner rotor

3

outer rotor

4

pump housing

5

ground

6

cover

7

first fluid connection

8th

second fluid connection

9

first opening

10

second opening

11

channel

12

inner peripheral surface

13

outer peripheral surface

14

third opening

15

body

16

face

17

face

18

mounting hole

19

mounting hole

20

support surface

21

drive shaft

22

opening

23

accommodation space

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102015002353 A1 [0004]
• WO 2006/136014 A1 [0006]

Claims (11)

Pump housing (4) for a gerotor pump (1), with a bottom (5) and with a lid (6), with a receiving space (23) arranged between the base (5) and the cover (6) and designed to receive an inner rotor and an outer rotor, with a first fluid connection (7) and with a second fluid connection (8), wherein the first fluid port (7) has a first opening (9) arranged on the bottom (5) in the receiving space (23) and a second opening (10) arranged on the cover (6) in the receiving space (23) the pump housing has at least one channel (11) which directly connects the first opening (9) and the second opening (10). Pump housing after Claim 1 , characterized in that the receiving space (23) with a from the bottom (5) extending, in particular circular, inner peripheral surface (12) is formed, which is designed for the positive reception of an outer rotor. Pump housing after Claim 2 , characterized in that the at least one channel (11) extends on the inner peripheral surface (12). Pump housing according to one of the preceding claims, characterized in that the at least one channel (11) is formed as an axial groove. Pump housing according to one of the preceding claims, characterized in that the first opening (9) and the second opening (10) via at least two channels (11), in particular via three channels (11) are connected. Pump housing after Claim 5 , characterized in that the channels (11) have a same cross section. Pump housing after Claim 5 or 6 , characterized in that between the channels (11) each have a support surface on the inner peripheral surface (12) for radially supporting a in the pump housing (4) accommodatable outer rotor (3) is provided. Gerotor pump (1), in particular for the automotive sector, with an inner rotor (2) and an outer rotor (3), with a pump housing (4) surrounding the outer rotor (3) in particular, in particular according to one of the preceding claims, which has a base (5) and a cover (6), the pump housing (4) having a first suction-side fluid connection (7) and a second pressure-side fluid connection (8), wherein the first fluid port (7) has a first port (9) provided as an inlet on the bottom (5) and a second port (10) provided as an inlet on the cap (6), and wherein the pump housing has at least one channel (11) which directly connects the first opening (9) and the second opening (10). Gerotor pump after Claim 8 characterized in that the at least one channel (11) is formed with a groove which, on its open longitudinal side between the first opening (9) and the second opening (10), is formed by an outer circumferential surface (13) of the outer rotor (3). is completed. Gerotor pump after Claim 8 or 9 , characterized in that the second fluid connection (8) has at least one third opening (14) provided as an outlet on the lid (6) and / or on the bottom (5). Gerotor pump after Claim 10 , characterized in that the outer rotor (3) is positively received in the pump housing (4) that the at least one third opening (14) relative to the first and second openings (9, 10) by the positive connection of the outer rotor (3 ) is sealed with the pump housing, at least substantially.

Images