Rotary Pump

Abstract

A rotary pump for delivering a fluid includes a pump housing having a first and a second fluid connections, wherein the first and the second fluid connections each open into a displacement chamber of the pump housing, a displacement rotor arranged in the displacement chamber, rotatable about an axis of rotation (D) in a first direction of rotation and a second direction of rotation opposite to the first direction of rotation, a plurality of displacement elements for delivering the fluid, distributed over the circumference of the displacement rotor, radially movable with respect to the axis of rotation (D), and designed to deliver the fluid from the first to the second fluid connection when the displacement rotor is rotated in the first direction of rotation, and to deliver the fluid from the second fluid connection to the first fluid connection when the displacement rotor is rotated in the second direction of rotation.

Claims

1. A rotary pump for delivering a fluid, the rotary pump comprising: a pump housing having a first fluid connection and a second fluid connection, wherein the first fluid connection and the second fluid connection each open into a displacement chamber of the pump housing; a displacement rotor arranged in the displacement chamber, wherein the displacement rotor is rotatable about an axis of rotation (D) in a first direction of rotation and a second direction of rotation opposite to the first direction of rotation; a plurality of displacement elements for delivering the fluid, wherein the plurality of displacement elements is distributed over the circumference of the displacement rotor and is radially movable with respect to the axis of rotation (D), wherein the displacement elements are configured to deliver the fluid to be delivered from the first fluid connection to the second fluid connection when the displacement rotor is rotated in the first direction of rotation, and to deliver the fluid to be delivered from the second fluid connection to the first fluid connection when the displacement rotor is rotated in the second direction of rotation.

2. The rotary pump according to claim 1, wherein the first fluid connection opens into a first chamber section of the displacement chamber and the second fluid connection opens into a second chamber section of the displacement chamber, wherein the first chamber section forms a suction zone and the second chamber section forms a pressure zone when the displacement rotor rotates in the first direction of rotation, and the first chamber section forms a pressure zone and the second chamber section forms a suction zone when the displacement rotor rotates in the second direction of rotation.

3. The rotary pump according to claim 2, wherein each two of the plurality of displacement elements arranged adjacent to one another in the circumferential direction of the displacement rotor, together with an outer circumferential surface of the displacement rotor and an inner circumferential surface of the displacement chamber delimit a displacement cell, wherein the volume of the respective displacement cell increases in the suction zone and decreases in the pressure zone when the displacement rotor rotates about the axis of rotation (D).

4. The rotary pump according to claim 1, wherein the radial movement of the displacement elements radially inward is delimited by a pressure chamber, wherein a fluid pressure introduced into the pressure chamber presses the displacement elements radially outward.

5. The rotary pump according to claim 2, wherein the radial movement of the displacement elements radially inward is delimited by a pressure chamber, wherein a fluid pressure introduced into the pressure chamber presses the displacement elements radially outward, and wherein the pressure chamber is connected in a fluid-communicating manner either to the first chamber section or to the second chamber section depending on the direction of rotation of the displacement rotor.

6. The rotary pump according to claim 2, wherein the radial movement of the displacement elements radially inward is delimited by a pressure chamber, wherein a fluid pressure introduced into the pressure chamber presses the displacement elements radially outward, wherein the pressure chamber is connected in a fluid-communicating manner to the second chamber section when the displacement rotor rotates in the first direction of rotation, and wherein the pressure chamber is connected in a fluid-communicating manner to the first chamber section when the displacement rotor rotates in the second direction of rotation.

7. The rotary pump according to claim 4 wherein the pressure chamber can is configured to be connected in a fluid-communicating manner via a valve to the fluid connections.

8. The rotary pump according to claim 7, wherein the valve is a double-acting check valve.

9. The rotary pump according to claim 7, wherein the valve is a ball valve.

10. The rotary pump according to claim 16, wherein the valve: connects the pressure chamber in a fluid-communicating manner to at least one of the second fluid connection or the second chamber section, and fluidically separates the pressure chamber from at least one of the first fluid connection or from the first chamber section, when the displacement rotor rotates in the first direction of rotation.

11. The rotary pump according to claim 7, wherein the valve connects the pressure chamber in a fluid-communicating manner to at least one of the first fluid connection or the first chamber section, and fluidically separates the pressure chamber from at least one of the second fluid connection or from the second chamber section, when the displacement rotor rotates in the second direction of rotation.

12. The rotary pump according to claim 1, wherein the first fluid connection forms a low-pressure inlet and the second fluid connection forms a high-pressure outlet when the displacement rotor rotates in the first direction of rotation, and the first fluid connection forms a high-pressure outlet and the second fluid connection forms a low-pressure inlet when the displacement rotor rotates in the second direction of rotation.

13. The rotary pump according to claim lone of the preceding claims, wherein the rotary pump is a rotary cell pump for delivering a hydraulic liquid.

14. A fluid system for the chassis of a vehicle, wherein the fluid system has a rotary pump according to claim 1.

15. The fluid system according to claim 14, wherein the fluid system has an actuator or a chassis actuator, and the actuator or the chassis actuator is connected in a fluid-communicating manner to one of the fluid connections such that the actuator or the chassis actuator is fluidically pressurized and depressurized by the rotary pump.

16. The rotary pump according to claim 4, wherein the first fluid connection opens into a first chamber section of the displacement chamber and the second fluid connection opens into a second chamber section of the displacement chamber, wherein the first chamber section forms a suction zone and the second chamber section forms a pressure zone when the displacement rotor rotates in the first direction of rotation, and the first chamber section forms a pressure zone and the second chamber section forms a suction zone when the displacement rotor rotates in the second direction of rotation, wherein the pressure chamber is configured to be connected in a fluid-communicating manner via a valve to at least one of the fluid connections or the chamber sections.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings used to explain the exemplary embodiment show:

[0029] FIG. 1 a schematic cross section of a rotary pump according to the invention, and

[0030] FIG. 2 a cross section in the longitudinal direction of a valve in the form of a double-acting check valve.

[0031] In principle, identical parts are provided with identical reference symbols in the figures.

WAYS OF CARRYING OUT THE INVENTION

[0032] FIG. 1 shows a schematic cross section of a rotary pump 1 according to the invention. The rotary pump 1 is configured for delivering a fluid. The rotary pump 1 comprises a pump housing 2 having a first fluid connection 3 and a second fluid connection 4. Both the first fluid connection 3 and the second fluid connection 4 open into a displacement chamber 5 of the pump housing 2. Arranged within the pump housing 2 is a displacement rotor 6, which is arranged eccentrically with respect to the displacement chamber 5 so as to be rotatable about an axis of rotation D. The displacement rotor 6 is configured to rotate in a first direction of rotation, for example counterclockwise, and in a second direction of rotation, for example clockwise, opposite to the first direction of rotation.

[0033] Displacement elements 7 are arranged around the circumference of the displacement rotor 6. The displacement elements 7 serve to deliver fluid by virtue of the radially movable displacement elements 7 being arranged depending on the distance between the displacement rotor 6 and the inner circumferential surface 11 of the displacement chamber 5 and thus forming displacement cells 12. The fluid thus remains enclosed in the displacement cells 12, wherein the volume changes as a result of the eccentricity of the displacement rotor 6 in the pump housing 2.

[0034] When the displacement rotor 6 rotates counterclockwise, the fluid to be delivered is delivered from the first fluid connection 3 to the second fluid connection 4. When the displacement rotor 6 rotates clockwise, the fluid to be delivered is delivered from the second fluid connection 4 to the first fluid connection 3. The fluid can thus be delivered depending on the direction of rotation of the displacement rotor 6 both from the first fluid connection 3 to the second fluid connection 4 and from the second fluid connection 4 to the first fluid connection 3. It is only necessary to change the direction of rotation of the rotary pump 1.

[0035] As a result of the displacement rotor 6, which is arranged eccentrically in the pump housing 2, the radially movable displacement elements 7 are immersed into associated pressure chambers 13 in the displacement rotor 6 depending on the distance between the displacement rotor 6 and the inner circumferential surface 11 of the displacement chamber 5.

[0036] Two displacement elements 7, which are arranged adjacent to one another in the circumferential direction of the displacement rotor 6, together with the outer circumferential surface 10 of the displacement rotor 6 and an inner circumferential surface 11 of the displacement chamber 5 delimit a displacement cell 12. The volume of the fluid within the formed displacement cells 12 changes depending on the direction of rotation of the displacement rotor 6 in the pump housing 2. If the volume within a displacement cell 12 decreases, the pressure increases accordingly and forms a pressure zone. If the volume within a displacement cell 12 increases, the pressure decreases accordingly and a suction zone is formed.

[0037] The first fluid connection 3 opens into a first chamber section 8 of the displacement chamber 5. When the displacement rotor 6 rotates clockwise, the fluid to be delivered is delivered from the second fluid connection 4 to the first fluid connection 3. In the first chamber section 8 of the displacement chamber 5, the volume within the displacement cells 12 decreases, the pressure increases accordingly and forms a pressure zone. In the second chamber section 9 of the displacement chamber 5, the volume within the displacement cells 12 increases, as a result of which the pressure decreases accordingly and forms a suction zone.

[0038] By contrast, when the displacement rotor 6 rotates counterclockwise, the fluid to be delivered is delivered from the first fluid connection 3 to the second fluid connection 4. In the first chamber section 8 of the displacement chamber 5, the volume within the displacement cells 12 increases, as a result of which the fluid pressure decreases and forms a suction zone. In the second chamber section 9 of the displacement chamber 5, the volume within the displacement cells 12 decreases, as a result of which the pressure increases accordingly and forms a pressure zone.

[0039] The pressure chambers 13 delimit the radial movement of the displacement elements 7 radially inward. In order to press the displacement elements 7 radially outward as continuously as possible, a fluid pressure is introduced into the pressure chambers 13 below the displacement elements 7. The fluid pressure is introduced by the respective pressure zone of the displacement chamber 5 either from the first chamber section 8 or from the second chamber section 9 depending on the direction of rotation of the displacement rotor 6. Thus, there is a fluidic connection between the pressure chamber 13 and the second chamber section 9 when the displacement rotor 6 rotates in the first direction of rotation, i.e. counterclockwise. Accordingly, the pressure chamber 13 is connected in a fluid-communicating manner to the first chamber section 8 when the displacement rotor 6 rotates in the second direction of rotation, i.e. clockwise.

[0040] FIG. 2 shows a cross section in the longitudinal direction of a valve 14 in the form of a double-acting check valve. The double check valve comprises a ball as valve body 18, which can be transferred between two opposing valve seats 15, 16. The first valve seat 15 directly adjoins the second fluid connection 4, which is in fluid connection with the second chamber section 9. The second valve seat 16 directly adjoins the first fluid connection 3, which is in fluid connection with the first chamber section 8. Via a pressure chamber port 17 on the valve 14, the pressure chamber 13 is connectable in a fluid-communicating manner via the valve 14 either to the first fluid connection 3 or to the second fluid connection 4 and the first chamber section 8 or the second chamber section 9.

[0041] Depending on the direction of rotation of the displacement rotor 6, the valve body 18 is transferred either into the first valve seat 15 or into the second valve seat 16. When the displacement rotor 6 rotates, for example, in the first direction of rotation, i.e. counterclockwise, the fluid pressure in the second chamber section 9 of the displacement chamber 5 increases and a pressure zone is formed. The pressure acts via the second fluid connection 4 on the spherical valve body 18 and transfers it into the second valve seat 16. As a result, the fluid connection is formed from the pressure zone via the pressure chamber port 17 to the pressure chamber 13, as a result of which the displacement elements 7 are pressed radially outward. By contrast, when the displacement rotor 6 rotates in the second direction of rotation, i.e. clockwise, the fluid pressure in the first chamber section 8 of the displacement chamber 5 increases and a pressure zone is formed. The pressure acts via the first fluid connection 3 on the spherical valve body 18 and transfers it to the first valve seat 15. As a result, the fluid connection is again formed from the pressure zone via the pressure chamber port 17 to the pressure chamber 13, as a result of which the displacement elements 7 are pressed radially outward. The displacement elements 7 are thus pressed continuously radially outward independently of the direction of rotation of the displacement rotor 6. As a result, the functionality of the rotary pump is optimized and leakages are further reduced.

TABLE-US-00001 Reference symbols 1 rotary pump 2 pump housing 3 First fluid connection 4 Second fluid connection 5 Displacement chamber 6 Displacement rotor 7 Displacement element 8 First chamber section 9 Second chamber section 10 Outer circumferential surface 11 Inner circumferential surface 12 displacement cell 13 Pressure chamber 14 Valve 15 First valve seat 16 Second valve seat 17 Pressure chamber port 18 Valve body D axis of rotation