Gerotor and pump apparatus having a gerotor device

Abstract

A gerotor device for a pump apparatus is disclosed. The gerotor device includes at least two gerotor stages that respectively include an inner rotor rotating during operation about an inner axis with teeth projecting radially outside, and an outer rotor rotating during operation about an outer axis radially offset relative to the inner axis with radially inner open tooth gaps, in which the teeth of the inner rotor engage. A rotor body rotating during operation about a rotor axis includes radially open tooth gaps of a first gerotor stage of the at least two gerotor stages and teeth projecting radially outside of a second gerotor stage of the at least two gerotor stages. The tooth gaps of the at least two gerotor stages are fluidically sealed at least one of against one another and relative to a surrounding area.

Claims

1. A gerotor device for a pump apparatus, comprising: at least two gerotor stages, wherein the at least two gerotor stages respectively comprises an inner rotor rotating during operation about an inner axis with teeth projecting radially outside and an outer rotor rotating during operation about an outer axis radially offset relative to the inner axis with radially inner open tooth gaps, in which the teeth of the inner rotor engage, a rotor body rotating during operation about a rotor axis comprises radially open tooth gaps of a first gerotor stage and teeth projecting radially outside of a second gerotor stage, a housing that receives the at least two gerotor stages, wherein the tooth gaps of the at least two gerotor stages are fluidically sealed at least one of against one another and relative to a surrounding area, and wherein the rotor body on at least one axial front side comprises an axially open and circumferential groove, and the housing comprises an axially projecting and circumferential rib, which for sealing the tooth gaps engages in the axially open and circumferential groove.

2. The gerotor device according to claim 1, wherein the rotor body, on another axial front side, comprises an axially open and circumferential groove, which for sealing is filled with a liquid.

3. The gerotor device according to claim 1, wherein: the housing comprises a housing pot with a radially extending pot bottom and a housing cover closing the housing pot and located axially opposite the pot bottom, the rotor body comprises a first front side located axially opposite the pot bottom with a first groove and the housing pot comprises a first rib projecting axially from the pot bottom, which engages in the first groove, and the rotor body further comprises a second front side located axially opposite the housing cover with a second groove and the housing cover comprises an axially projecting second rib, which engages in the second groove.

4. The gerotor device according to claim 1, wherein: the rotor body, on at least one axial front side, comprises a cylinder portion projecting radially inside and axially, in which the tooth gaps are at least partially formed, and which protrudes over the second gerotor stage axially, and the housing for the cylinder portion comprises an associated receptacle in which the cylinder portion for sealing the tooth gaps engages axially.

5. The gerotor device according to claim 4, wherein: the housing comprises a housing pot with a radially extending pot bottom and a housing cover closing the housing pot and located axially opposite the pot bottom, the rotor body comprises a first cylinder portion projecting axially in a direction of the pot bottom and the housing pot comprises a first receptacle directed axially to the inside, in which the first cylinder portion engages axially, the rotor body comprises a second cylinder portion projecting axially in a direction of the housing cover and the housing cover comprises a second receptacle directed axially to the inside, in which the second cylinder portion engages axially.

6. The gerotor device according to claim 1, wherein the rotor body forms the inner rotor of the first gerotor stage and the outer rotor of the second gerotor stage.

7. The gerotor device according to claim 1, wherein the rotor body is structured monolithically.

8. The gerotor device according to claim 1, wherein the rotor body is a sintered component.

9. A pump apparatus for pumping at least one liquid, comprising: a cavity, through which at least one flow path leads, and a gerotor device arranged in the cavity, which during operation delivers the at least one liquid, the gerotor device including: at least two gerotor stages that respectively comprise an inner rotor rotating during operation about an inner axis with teeth projecting radially outside, and an outer rotor rotating during operation about an outer axis radially offset relative to the inner axis with radially inner open tooth gaps, in which the teeth of the inner rotor engage; a rotor body rotating during operation about a rotor axis comprises radially open tooth gaps of a first gerotor stage of the at least two gerotor stages and teeth projecting radially outside of a second gerotor stage of the at least two gerotor stages; a housing that receives the at least two gerotor stages; wherein the tooth gaps of the at least two gerotor stages are fluidically sealed at least one of against one another and relative to a surrounding area; and wherein the rotor body on at least one axial front side comprises an axially open and circumferential groove, and the housing comprises an axially projecting and circumferential rib, which for sealing the tooth gaps engages in the axially open and circumferential groove.

10. The pump apparatus according to claim 9, wherein the rotor body, on another axial front side, comprises an axially open and circumferential groove, which for sealing is filled with oil.

11. The pump apparatus according to claim 9, wherein: the housing comprises a housing pot with a radially extending pot bottom and a housing cover closing the housing pot and located axially opposite the pot bottom; the rotor body comprises a first front side located axially opposite the pot bottom with a first groove and the housing pot comprises a first rib projecting axially form the pot bottom, which engages in the first groove; and the rotor body comprises a second front side located axially opposite the housing cover with a second groove and the housing cover comprises an axially projecting rib, which engages in the second groove.

12. The pump apparatus according to claim 9, wherein: the rotor body on at least one axial front side comprises a cylinder portion projecting radially inside and axially, in which the tooth gaps are at least partially formed, and which protrudes over the second gerotor stage axially; and the housing for the cylinder portion comprises an associated receptacle in which the cylinder portion for sealing the tooth gaps engages axially.

13. The pump apparatus according to claim 12, wherein: the housing comprises a housing pot with a radially extending pot bottom and a housing cover closing the housing pot and located axially opposite the pot bottom; the rotor body comprises a first cylinder portion projecting axially in a direction of the pot bottom and the housing pot comprises a first receptacle directed axially to the inside, in which the first cylinder portion engages axially; and the rotor body comprises a second cylinder portion projecting axially in a direction of the housing cover and the housing cover comprises a second receptacle directed axially to the inside, in which the second cylinder portion engages axially.

14. The pump apparatus according to claim 9, wherein the rotor body forms the inner rotor of the first gerotor stage and the outer rotor of the second gerotor stage.

15. The pump apparatus according to claim 9, wherein the rotor body is structured monolithically.

16. A motor vehicle, comprising: a transmission and a pump apparatus, wherein the pump apparatus during operation supplies a liquid to the transmission; the pump apparatus including a gerotor device, the gerotor device including: at least two gerotor stages that respectively comprise an inner rotor rotating during operation about an inner axis with teeth projecting radially outside, and an outer rotor rotating during operation about an outer axis radially offset relative to the inner axis with radially inner open tooth gaps, in which the teeth of the inner rotor engage; a rotor body rotating during operation about a rotor axis comprises radially open tooth gaps of a first gerotor stage of the at least two gerotor stages and teeth projecting radially outside of a second gerotor stage of the at least two gerotor stages; a housing that receives the at least two gerotor stages; wherein the tooth gaps of the at least two gerotor stages are fluidically sealed at least one of against one another and relative to a surrounding area; and wherein the rotor body on at least one axial front side comprises an axially open and circumferential groove, and the housing comprises an axially projecting and circumferential rib, which for sealing the tooth gaps engages in the axially open and circumferential groove.

17. The motor vehicle according to claim 16, wherein the rotor body, on another axial front side, comprises an axially open and circumferential groove, which for sealing is filled with oil.

18. The motor vehicle according to claim 16, wherein the rotor body forms the inner rotor of the first gerotor stage and the outer rotor of the second gerotor stage.

19. The motor vehicle according to claim 16, wherein: the housing comprises a housing pot with a radially extending pot bottom and a housing cover closing the housing pot and located axially opposite the pot bottom; the rotor body comprises a first front side located axially opposite the pot bottom with a first groove and the housing pot comprises a first rib projecting axially form the pot bottom, which engages in the first groove; and the rotor body comprises a second front side located axially opposite the housing cover with a second groove and the housing cover comprises an axially projecting rib, which engages in the second groove.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) It shows, in each case schematically

(2) FIG. 1 an axial plan view of a gerotor device,

(3) FIG. 2 an isometric view of a pump apparatus with the gerotor device,

(4) FIG. 3 a section through the pump apparatus with the gerotor device in another exemplary embodiment,

(5) FIG. 4 an isometric view of the gerotor device in a further exemplary embodiment,

(6) FIG. 5 a simplified lateral view of the gerotor device from FIG. 4,

(7) FIG. 6 a highly simplified representation in the manner of a circuit diagram of the pump apparatus in a motor vehicle,

(8) FIG. 7 a highly simplified representation in the manner of a circuit diagram of the pump apparatus in another exemplary embodiment.

DETAILED DESCRIPTION

(9) A gerotor device 1, such as is shown for example in the FIGS. 1 to 7, is employed in a pump apparatus 100 shown for example in the FIGS. 2 and 3 as well as 6 and 7 for delivering at least one liquid. The gerotor device 1, as is evident in particular from FIG. 1, comprises at least two gerotor stages 2. In the shown exemplary embodiments, the gerotor device 1 comprises two gerotor stages 2, namely a first gerotor stage 2, 2a and a second gerotor stage 2, 2b. The respective gerotor stage 2 comprises an inner rotor 4 rotating during the operation about an inner axis 3 having projecting teeth 7 radially outside and an outer rotor 6 rotating during the operation about an outer axis 5 offset radially with respect to the inner axis 3 with tooth gaps 8 open radially inside, in which during the operation the teeth 7 of the inner rotor 4 engage. Thus, the first gerotor stage 2, 2a comprises a first inner rotor 4, 4a rotating during the operation about a first inner axis 3, 3a with first teeth 7, 7a projecting radially to the outside and a first outer rotor 6, 6a rotating during the operation about a first outer axis 5, 5a offset radially with respect to the first inner axis 3 with first tooth gaps 8, 8a open radially inside. During the operation, the first teeth 7, 7a of the first inner rotor 4, 4a engage in the tooth gaps 8, 8a of the first outer rotor 6, 6a. Similar to this, the second gerotor stage 2, 2b comprises a second inner rotor 4, 4b rotating during the operation about a second inner axis 3, 3b with second teeth 7, 7b projecting radially outside and a second outer rotor 6, 6b rotating during the operation about a second outer axis 5, 5b offset radially to the second inner axis with second tooth gaps 8, 8b open radially inside. During the operation, the second teeth 7, 7b of the second inner rotor 4, 4b engage in the second tooth gaps 8, 8b of the second outer rotor 6, 6a.

(10) As is evident from the FIGS. 1 to 3, the gerotor device 1 comprises a rotor body 10 rotating during the operation about a rotor axis 9, which comprises radially open tooth gaps 8, 8a of the first gerotor stage 2, 2a and teeth 7, 7b of the second gerotor stage 2, 2b projecting radially to the outside. In the shown exemplary embodiments, the rotor body 10 forms the inner rotor 4, 4a of the first gerotor stage 2, 2a and the outer rotor 6, 6b of the second gerotor stage 2, 2b. Thus, the rotor body 10 comprises the first tooth gaps 8, 8a open radially inside of the first gerotor stage 2, 2a and the second teeth 8, 8b projecting radially outside of the second gerotor stage 2, 2b.

(11) The direction radial stated here refers to the respective associated axis 3, 5, 9. The axes 3, 5, 9 run parallel. The direction axial stated here relates to the respectively associated axis 3, 5, 9, wherein axial runs parallel or coaxially to the axis.

(12) In the shown exemplary embodiments, the rotor body 10 is formed in one part and monolithically. The rotor body 10 is for example a sintered component 11. The rotor body 10 is thus produced for example by sintering.

(13) In the shown exemplary embodiments, the rotor axis 9 of the rotor body 10 forms the outer axis 5, 5a of the first gerotor stage 2, 2a and the inner axis 3, 3b of the second gerotor stage 2, 2b. The rotor axis 9 of the rotor body 10 is thus arranged in such a manner that a parallel operation of both transmission stages 10 is made possible. As is evident from the FIGS. 1 to 3, the outer rotor 6, 6b of the second gerotor stage 2, 2b shown in the exemplary embodiments is arranged so as to enclose the rotor body 10. This means that the outer rotor 6, 6b of the second gerotor stage 2, 2b encloses the rotor body 10 radially outside. Thus, the first gerotor stage 2, 2a is a radially inner gerotor stage 2, 2a and the second gerotor stage 2, 2b a radially outer gerotor stage 2, 2b of the gerotor device 1.

(14) In the shown exemplary embodiments, the gerotor device 1 comprises a housing 15 merely shown in the FIGS. 3 and 5, in which gerotor stages 2 are received. The housing 15 comprises a housing pot 17 and a radially extending pot bottom 18 and a housing cover 19 closing the housing pot 17 and is located axially opposite the pot bottom 18.

(15) As is evident from the FIGS. 2 to 5, the tooth gaps 8 of the gerotor stages 2 and thus the gerotor stages 2 are fluidically sealed against one another and relative to the surrounding area. In this way, internal leakages of the gerotor device 1 are avoided or at least reduced. In addition it is avoided in this way that the gerotor stage 2 operated at a lower pressure level, in particular the tooth gaps 8 of the gerotor stage 2 operated with the lower pressure level, suctions air from the surrounding area or such a suctioning is at least reduced.

(16) In the exemplary embodiment shown in the FIGS. 1 to 3, the rotor body, for sealing the tooth gaps 8, comprises at least on an axial front side 14, an axially open and circumferential groove 14, wherein the groove 14 is merely indicated in FIG. 1.

(17) In the exemplary embodiment shown in the FIGS. 1 and 2, the rotor body 10, on an axial front side 14, comprises an axially open and circumferential groove 14, which for sealing the tooth gaps 18 is filled with a liquid, in particular with oil.

(18) In the exemplary embodiment shown in FIG. 3, the rotor body 10 comprises on at least one axial front side 13 an axially open and circumferential groove 14. In addition, the housing 15 comprises for the respective at least one groove 14 an axially projecting and circumferential rib 16, which for sealing the tooth gaps 8 engages in the associated groove labyrinth seal. In the exemplary embodiment shown in FIG. 3, the rotor body 10 comprises on the 14. The groove 14 and the associated rib 16 interact in the manner of a respective front side 13 a groove 14 and the housing 15 for the respective groove 14, an associated rib 16. In the shown exemplary embodiment, the rotor body 10 comprises a first front side 13, 13a located axially opposite the pot bottom 18, with a first groove 14, 14a and the housing pot 17 a first rib 16, 16a axially projecting from the pot bottom, which engages in the first groove 14, 14a. In addition, the rotor body 10 comprises a second front side 13, 13b located axially opposite the housing cover 19 with a second groove 14, 14b and the housing cover 19 an axially projecting second rib 16, 16b, which engages in the second groove 14, 14b.

(19) In the exemplary embodiments shown in the FIGS. 1 to 3, the teeth 7, 7a and the tooth gaps 8, 8a of the rotor body 10 are arranged at the same axial height. As is evident in particular from FIG. 2, the first inner rotor 4, 4a, the rotor body 10 as well as the second outer rotor 6, 6b terminate axially identically in these exemplary embodiments, are thus situated axially in a radial plane. Thus, a compact construction of the gerotor device 1 is achieved.

(20) The exemplary embodiment shown in the FIGS. 4 and 5 differs from the exemplary embodiments shown in the FIGS. 1 to 3 in that the rotor body 10, on at least one of the axial front sides 13, is formed axially stepped. Thus, the rotor body 10 comprises on the front side 13 at least two steps 12 radially offset relative to one another, which axially merge into one another. In the shown exemplary embodiment, the rotor body 10 comprises two such steps 12, namely a radially inner step 12, 12a and a radially outer step 12, 12b. The radially inner step 12, 12a protrudes over the radially outer step 12, 12b of the rotor body 10 and the outer rotor 6, 6b of the second gerotor stage 2, 2b axially. By contrast, the radially inner step 12, 12a terminates axially on the front side with the outer rotor 6, 6b of the second gerotor stage 2, 2b. Thus, the rotor body 10 comprises on the stepped front side 13 an axially projecting and cylindrical portion 20, which in the following is also referred to as cylinder portion. The cylinder portion 20 protrudes over the second gerotor stage 2, 2b axially. In addition, the tooth gaps 8 in the cylinder portion 20 are at least partially formed so that the tooth gaps 8 extend into the cylinder portion 20. In the shown exemplary embodiments, the first tooth gaps 8, 8a thus extend into the cylinder portion 20. For sealing the teeth 8, the housing 15, as is merely shown in FIG. 5 in a simplified manner, comprises for the respective cylinder portion 20 an associated receptacle 21, in which the cylinder portion 20 for sealing the tooth gaps 8 engages axially. The cylinder portion 20 is sealed in the associated receptacle 21. In addition, the cylinder portion 20 and thus the rotor body 10 can be mounted in the associated receptacle 21 via the cylinder portion 20.

(21) As is evident from FIG. 5, the rotor body 10, in the shown exemplary embodiment, comprises one such cylinder portion 20 on the respective front side 13. Thus, the rotor body 10 comprises a first cylinder portion 20, 20a projecting axially in the direction of the pot bottom 18 and the housing pot 17 a first receptacle 21, 21a directed axially to the inside, in which the cylinder portion 20, 20a engages axially. In addition, the rotor body 10 comprises a second cylinder portion 20, 20b projecting axially in the direction of the housing cover 19 and the housing cover 19 a second receptacle 21, 21b directed axially to the inside, in which the second cylinder portion 20, 20b engages axially.

(22) Further, the exemplary embodiment shown in the FIGS. 4 and 5 differs from the exemplary embodiments shown in the FIGS. 1 to 3 in that the tooth gaps 8, 8b of the rotor body 10 axially protrude over the teeth 7, 7a of the rotor body 10. In the shown exemplary embodiment, the teeth 7, 7a of the rotor body 10 axially project out of the second outer rotor 6, 6b. Further, the first teeth 7, 7a project axially out of the second outer rotor 6, 6b. The first teeth 7, 7a and the first tooth gaps 8, 8a can thus have an axially greater extent than the second teeth 7, 7b and the second tooth gaps 8, 8b. Thus, it is possible for example with the gerotor stage 2, 2a to transmit greater moments than with the second gerotor stage 2, 2b.

(23) The pump apparatus 100, as is evident from FIG. 2 and indicated in the FIGS. 6 and 7, comprises a cavity 102 in which the gerotor device 1 is arranged and delivers at least one liquid during the operation. Thus, a flow path 103 indicated by arrows in the FIGS. 6 and 7 of the at least one liquid leads through the cavity 102.

(24) According to FIG. 6, a single liquid can be delivered and thus pumped in a stepped manner with the gerotor device 1 by means of the gerotor stages 2. Thus, a flow path 103 leads through the cavity 22. According to FIG. 7, it is also possible with the gerotor device 1 to deliver two liquids or the same liquid in two separate circuits. In particular, the liquids can be delivered in the circuits with different pressures or volumetric flows. Thus, a gerotor stage 2 is provided for the respective liquid. Accordingly, a first flow path 103, 103a and a second flow path 103, 103b leads through the cavity 102.

(25) According to FIG. 6, the pump apparatus 100 can be employed in a motor vehicle 200. In the motor vehicle 200, the pump apparatus 100 can supply for example a transmission 201 with oil and/or lubricant as liquid, thus supply oil and/or lubricant to the transmission. Thus, the pump apparatus 100 can be in particular an oil pump 104.