FLUID DELIVERY SYSTEM WITH LOAD-DEPENDENT ROTATIONAL SPEED REVERSAL OF A ROTARY PUMP

Abstract

A fluid delivery system includes a reservoir for storing fluid, a rotary pump having a first pump port and a second pump port, a first fluid conduit connecting the first pump port to the reservoir, and a second fluid conduit connecting the second pump port to the reservoir. The rotary pump rotates in a first delivery direction in a normal mode and in a second delivery direction in an alternative mode. A first valve separates the first pump port from the reservoir when the rotary pump is in its alternative mode, and a second valve separates the second pump port from the reservoir when the rotary pump is in its normal mode.

Claims

1-15. (canceled)

16. A fluid delivery system for supplying fluid to a machine assembly, the fluid delivery system comprising: a) a reservoir for storing the fluid; b) a rotary pump having a first pump port and a second pump port; c) a drive for driving the pump; d) a first fluid conduit featuring a first valve and a second fluid conduit featuring a second valve, e) wherein the first fluid conduit connects the first pump port to the reservoir, and the second fluid conduit connects the second pump port to the reservoir, and f) the rotary pump can be operated in a normal mode, in which it rotates in a first delivery direction, and an alternative mode in which it rotates in a second delivery direction, wherein g) the first valve separates the first pump port from the reservoir when the rotary pump is in its alternative mode, and the second valve separates the second pump port from the reservoir when the rotary pump is in its normal mode.

17. The fluid delivery system according to the claim 16, wherein when it is in its normal mode, the rotary pump suctions the fluid via the first pump port and discharges it via the second pump port, and when the rotary pump is in its alternative mode, it suctions the fluid via the second pump port and discharges it via the first pump port.

18. The fluid delivery system according to claim 16, wherein the first fluid conduit emerges into the reservoir at a first aspiration point, and the second fluid conduit emerges into the reservoir at a second aspiration point, wherein the first aspiration point and the second aspiration point are spaced apart from each other.

19. The fluid delivery system according to claim 16, wherein the reservoir comprises a main sump, an ancillary sump and an overflow, wherein the fluid flows from the machine assembly back to the main sump, and the main sump is fluidically connected to the ancillary sump via the overflow.

20. The fluid delivery system according to claim 19, wherein the first fluid conduit emerges into the reservoir at a first aspiration point, and the second fluid conduit emerges into the reservoir at a second aspiration point, wherein the first aspiration point and the second aspiration point are spaced apart from each other, and wherein the first aspiration point emerges into the main sump and the second aspiration point emerges into the ancillary sump.

21. The fluid delivery system according to claim 16, further comprising a third fluid conduit which features a third valve and connects the second pump port to the machine assembly, and a fourth fluid conduit which features a fourth valve and connects the first pump port to the machine assembly.

22. The fluid delivery system according to claim 21, wherein the third fluid conduit emerges into the second fluid conduit at its end which faces away from the machine assembly, and the fourth fluid conduit emerges into the first fluid conduit at its end which faces away from the machine assembly.

23. The fluid delivery system according to claim 21, wherein when the rotary pump is in its alternative mode, the third valve prevents a fluid flow outside a delivery chamber of the rotary pump from the first pump port to the second pump port, and when the rotary pump is in its normal mode, the fourth valve prevents a fluid flow outside the delivery chamber of the rotary pump from the second pump port to the first pump port.

24. The fluid delivery system according to claim 16, wherein both the first valve and the second valve are formed by a check valve.

25. The fluid delivery system according to claim 16, wherein the drive comprises an electric motor.

26. The fluid delivery system according to claim 25, further comprising a motor controller for actuating the electric motor, wherein the motor controller comprises monitoring electronics for detecting that air is being suctioned.

27. The fluid delivery system according to claim 26, wherein the monitoring electronics are provided to monitor a power consumption of the electric motor as a function of an actual rotational speed of the rotary pump and/or electric motor and/or an actual temperature of the fluid and/or rotary pump.

28. The fluid delivery system according to claim 27, wherein the motor controller changes the rotational direction of the electric motor when the power consumption as a function of the actual rotational speed of the rotary pump and/or electric motor and/or the actual temperature of the fluid and/or rotary pump falls below a threshold value.

29. The fluid delivery system according to claim 27, wherein the motor controller changes the rotational direction of the electric motor for at least one second or at least five seconds when the power consumption as a function of the actual rotational speed of the rotary pump and/or electric motor and/or the actual temperature of the fluid and/or rotary pump falls below a threshold value.

30. A method for operating a fluid delivery system for supplying fluid to a machine assembly, the system comprising an electric motor which rotates in a first rotational direction when it is in a normal mode and in a second rotational direction when it is in an alternative mode, a rotary pump which is driven by the electric motor and suctions the fluid from a reservoir via a first pump port and discharges it via a second pump port when the electric motor is in its normal mode and suctions the fluid from the reservoir via the second pump port and discharges it via the first pump port when the electric motor is in its alternative mode, and a motor controller comprising monitoring electronics, the method comprising: a) a power consumption of the electric motor is detected; b) an actual rotational speed of the rotary pump and/or an actual temperature of the fluid and/or rotary pump is detected; c) the power consumption is compared with a threshold value for the power consumption, wherein the threshold value is predetermined or determined as a function of the detected actual rotational speed and/or the detected actual temperature of the fluid and/or rotary pump; and d) the motor controller switches the electric motor from its normal mode to its alternative mode or from its alternative mode to its normal mode, if the power consumption falls below the threshold value.

31. A method for operating a fluid delivery system according to claim 16, the method comprising: a) a power consumption of the electric motor is detected; b) an actual rotational speed of the rotary pump and/or an actual temperature of the fluid and/or rotary pump is detected; c) the power consumption is compared with a threshold value for the power consumption, wherein the threshold value is predetermined or determined as a function of the detected actual rotational speed and/or the detected actual temperature of the fluid and/or rotary pump; and d) the motor controller switches the electric motor from its normal mode to its alternative mode or from its alternative mode to its normal mode, if the power consumption falls below the threshold value.

32. The fluid delivery system according to claim 21, wherein both the first valve and the second valve are formed by a first check valve, and wherein both the third valve and the fourth valve are formed by a second check valve.

33. The fluid delivery system according to claim 26, wherein the monitoring electronics are configured for detecting that air is being suctioned through the first and/or second fluid conduit.

34. The fluid delivery system according to claim 22, wherein when the rotary pump is in its alternative mode, the third valve prevents a fluid flow outside a delivery chamber of the rotary pump from the first pump port to the second pump port, and when the rotary pump is in its normal mode, the fourth valve prevents a fluid flow outside the delivery chamber of the rotary pump from the second pump port to the first pump port.

35. The fluid delivery system according to claim 28, wherein the motor controller changes the rotational direction of the electric motor for at least one second or at least five seconds when the power consumption as a function of the actual rotational speed of the rotary pump and/or electric motor and/or the actual temperature of the fluid and/or rotary pump falls below a threshold value.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0070] The invention shall be described below on the basis of example embodiments. The invention is described in the following on the basis of example embodiments. The features disclosed in the example embodiments advantageously develop the subject-matter of the claims and the embodiments described above.

[0071] There is shown:

[0072] FIG. 1 a hydraulic circuit diagram according to a first example embodiment;

[0073] FIG. 2 a hydraulic circuit diagram according to a second example embodiment; and

[0074] FIG. 3 a hydraulic circuit diagram according to a third example embodiment.

DETAILED DESCRIPTION OF THE INVENTION

[0075] FIG. 1 shows a fluid delivery system according to a first example embodiment. The fluid delivery system comprises a rotary pump 5 having a first pump port 51 and a second pump port 52. The rotary pump 5 can be operated in a normal mode, in which it rotates in a first rotational direction, and an alternative mode in which it rotates in a second rotational direction. The fluid delivery system also comprises a reservoir 6 from which the rotary pump 5 can suction fluid and deliver it to a machine assembly A. The machine assembly A is preferably the engine and/or gear system of a motor vehicle. Once the fluid has for example lubricated and/or cooled the machine assembly A, it can flow from the machine assembly A back to the reservoir 6. The fluid delivery system thus represents a fluid circuit. Contrary to the representation in FIG. 1, the reservoir 6 is preferably embodied below the machine assembly A, in particular at a lowest point of the machine assembly A, such that the fluid can flow back into the reservoir 6 due to gravity. The reservoir 6 can in particular be part of the machine assembly A and for example form the lower part of an assembly housing.

[0076] The reservoir 6 is preferably embodied as a flat reservoir. The reservoir 6 can in particular be embodied in the form of a flat tray. The reservoir 6 is preferably connected, in particular screwed, to the housing of the machine assembly A. The reservoir 6 can be manufactured from metal or plastic, in particular in an original-moulding method or a reshaping method. The reservoir 6 can preferably be manufactured from sheet material, in particular by deep-drawing.

[0077] The first pump port 51 is fluidically connected to the reservoir 6 via a first fluid conduit 1. The first fluid conduit 1 extends from the first pump port 51 via a first valve 11 up to a first aspiration point 10 formed in the reservoir 6. The first valve 11 is embodied in the form of a reflux valve which can assume a release position and a blocking position. When the rotary pump 5 is in its normal mode, in which it rotates in a first rotational direction, the first valve 11 is situated in the release position and opens the first fluid conduit 1, such that fluid can be suctioned from the reservoir 6 by the rotary pump 5 via the first pump port 51. When the rotary pump 5 is in its alternative mode, the first valve 11 is situated in the blocking position, such that fluid cannot pass to the reservoir 6 via the first pump port 51 and the first fluid conduit 1. In particular, the fluid pressure in the first fluid conduit 1 ensures that a blocking body of the first valve 11 is pressed into the valve seating and closes the first valve 11 when the rotary pump 5 is in its alternative mode.

[0078] The second pump port 52 is fluidically connected to the reservoir 6 via a second fluid conduit 2. The second fluid conduit 2 extends from the second pump port 52 via a second valve 12 up to a second aspiration point 20 formed in the reservoir 6. The second valve 12 is embodied in the form of a reflux valve which can assume a release position and a blocking position. When the rotary pump 5 is in its alternative mode, in which it rotates in a second rotational direction, the second valve 12 is situated in its release position and opens the second fluid conduit 2, such that fluid can be suctioned from the reservoir 6 by the rotary pump 5 via the second pump port 52. When the rotary pump 5 is in its normal mode, the second valve 12 is situated in the blocking position, such that fluid cannot pass to the reservoir 6 via the second pump port 52 and the second fluid conduit 2. In particular, the fluid pressure in the second fluid conduit 2 ensures that a blocking body of the second valve 12 is pressed into the valve seating and closes the second valve 12 when the rotary pump 5 is in its normal mode.

[0079] The first pump port 51 is connected to the machine assembly A via a fourth fluid conduit 4 having a fourth valve 41. The fourth fluid conduit 4 emerges into the first fluid conduit 1 at its end which faces away from the machine assembly A. The fourth valve 41 is arranged between the machine assembly A and the intersection at which the fourth fluid conduit 4 emerges into the first fluid conduit 1 at its end which faces away from the machine assembly A.

[0080] The fourth valve 41 is embodied in the form of a check valve which exhibits a release position, in which the fourth valve 41 opens the fourth fluid conduit 4, and a blocking position in which the fourth valve 41 closes the fourth valve conduit 4. When the fourth valve 41 is in its release position, fluid can pass from the first pump port 51 to the machine assembly A via the fourth valve conduit 4 and in particular via the first fluid conduit 1. The fourth valve 41 is situated in the release position when the rotary pump 5 is in its alternative mode and in the blocking position when the rotary pump 5 is in its normal mode. In particular, the fluid pressure in the first fluid conduit 1 and the fourth fluid conduit 4 ensures that a blocking body of the fourth valve 41 is pressed out of the valve seating when the rotary pump 5 is in its alternative mode, such that the fourth valve 41 assumes its release position. When the rotary pump 5 is in its normal mode, the fourth valve 41 can in particular prevent a fluid flow outside the delivery chamber of the rotary pump 5 from the second pump port 52 to the first pump port 51, such that fluid can only pass from the second pump port 52 to the first pump port 51 through the delivery chamber.

[0081] The second pump port 52 is connected to the machine assembly A via a third fluid conduit 3 having a third valve 31. The third fluid conduit 3 emerges into the second fluid conduit 2 at its end which faces away from the machine assembly A. The third fluid conduit 3 also emerges into the fourth fluid conduit 4 at its end which faces the machine assembly A. The third valve 31 is embodied between the intersection at which the third fluid conduit 3 emerges into the second fluid conduit 2 at its end which faces away from the machine assembly A and the intersection at which the third fluid conduit 3 emerges into the fourth fluid conduit 4 at its end which faces the machine assembly A.

[0082] The third valve 31 is embodied in the form of a check valve which can assume a release position and a blocking position. When the third valve 31 is in its release position, fluid can pass from the second pump port 52 to the machine assembly A via the third fluid conduit 3 and in particular via the second fluid conduit 2 and the third fluid conduit 3. The third valve 31 is situated in the release position when the rotary pump 5 is in its normal mode and in the blocking position when the rotary pump 5 is in its alternative mode. In particular, the fluid pressure in the third fluid conduit 3 ensures that a blocking body of the third valve 31 is pressed out of the valve seating when the rotary pump 5 is in its normal mode, such that the third valve 31 assumes its release position. When the rotary pump 5 is in its alternative mode, the third valve 31 can in particular prevent a fluid flow outside the delivery chamber of the rotary pump 5 from the first pump port 51 to the second pump port 52, such that fluid can only pass from the first pump port 51 to the second pump port 52 through the delivery chamber.

[0083] The rotary pump 5 is driven by an electric motor 7. The fluid delivery system comprises a motor controller for actuating the electric motor 7. The motor controller preferably comprises monitoring electronics which are designed to detect whether the rotary pump 5 is suctioning air via one of the aspiration points 10, 20. The monitoring electronics of the fluid delivery system are provided to monitor the power consumption of the electric motor 7 as a function of an actual rotational speed of the rotary pump 5 and/or electric motor 7 and as a function of the temperature of the rotary pump 5 or fluid. If the power consumption drops below a threshold value to be determined or a defined threshold value, the rotational direction of the electric motor 7 and thus the rotational direction of the rotary pump 5 is changed, i.e. when the power consumption drops below a threshold value, the motor controller switches the electric motor 7 and therefore the rotary pump 5 from its normal mode to its alternative mode.

[0084] The motor controller can change the rotational direction of the electric motor 7 for at least one second, in particular at least five seconds, or it leaves the rotational direction of the electric motor 7 as it is until the threshold value of the power consumption as a function of the actual rotational speed of the rotary pump 5 and/or the actual temperature of the fluid and/or rotary pump 5 drops below a threshold value again.

[0085] FIG. 2 shows a fluid delivery system according to a second example embodiment. The fluid delivery system according to FIG. 2 differs from the fluid delivery system according to FIG. 1 only in the embodiment of the reservoir 6. Only the differences between the two example embodiments will therefore be discussed in the following. Features of the first example embodiment in FIG. 1 and their description also apply to the second example embodiment, providing they do not contradict the example embodiment according to FIG. 2.

[0086] The reservoir 6 in FIG. 2 differs from the reservoir 6 in FIG. 1 in that the reservoir is sub-divided into a main sump 61 and an ancillary sump 62. The main sump 61 and the ancillary sump 62 are fluidically connected to each other via an overflow 63. When the fluid delivery system is in operation, the fluid preferably flows from the machine assembly A back to the main sump 61, where it is aspirated by the rotary pump 5 in its normal mode via the first aspiration point 10 and discharged to the machine assembly A. The overflow 63 is embodied in the form of a separating wall of the reservoir 6, wherein the separating wall does not extend as far as in the depth direction of the reservoir 6 as the reservoir 6.

[0087] When the rotary pump 5 is in its alternative mode, it aspirates the fluid from the ancillary sump 62 via the aspiration point 20. If the fluid delivery system is provided as a fluid delivery system for an engine and/or gear system of a motor vehicle, the fluid can flow from the main sump 61 to the ancillary sump 62 and/or from the ancillary sump 62 to the main sump 61 via the overflow 63 when centrifugal forces are acting on the fluid.

[0088] If the fluid is pressed onto the left-hand side of the reservoir 6, as shown by a dashed line in the ancillary sump 62 in FIG. 2, it can transpire that the aspiration point 10 is above the fluid level in the main sump 61. This lowers the power consumption of the electric motor 7 when the rotary pump 5 is in its normal mode, and the motor controller switches the electric motor 7 from its normal mode to its alternative mode if the power consumption falls below the threshold value.

[0089] The overflow 63 then ensures that when the centrifugal forces on the fluid cease and in particular when the motor controller automatically switches from the alternative mode back to the normal mode, sufficient fluid remains in the main sump 61, such that the first aspiration point 10 is below the fluid level in the main sump 61.

[0090] According to the example embodiment in FIG. 2, the main sump 61 has a smaller holding volume than the ancillary sump 62. In alternative embodiments, the main sump 61 and the ancillary sump 62 can have the same holding volume, or the ancillary sump 62 can have a smaller holding volume than the main sump 61.

[0091] The example embodiment according to FIG. 3 differs from the example embodiments in FIGS. 1 and 2 in the embodiment of the fluid conduits. Only the essential differences between the third example embodiment and the two preceding example embodiments will therefore be discussed in the following. Features of the first example embodiment and the second example embodiment and their description also apply to the third example embodiment, providing they do not contradict the example embodiment according to FIG. 3.

[0092] Contrary to the two preceding example embodiments, the fourth fluid conduit 4 does not emerge into the first fluid conduit 1 at its end which faces away from the machine assembly A. The fourth fluid conduit 4 extends from the first pump port 51 up to the machine assembly A. The first fluid conduit 1 extends from the first pump port 51 up to the first aspiration point 10 via the first valve 11. The first pump port 51 is thus connected, in particular directly connected, to both the first fluid conduit 1 and the fourth fluid conduit 4.

[0093] The third fluid conduit 3 also does not emerge into the second fluid conduit 2 at its end which faces away from the machine assembly A. The third fluid conduit 3 also does not emerge into the fourth fluid conduit 4 at its end which faces the machine assembly A. The third fluid conduit 3 thus extends from the second pump port 52 up to the machine assembly A. The second fluid conduit 2 extends from the second pump port 52 up to the second aspiration point 20 via the second valve 21. The second pump port 52 is thus connected, in particular directly connected, to both the third fluid conduit 3 and the second fluid conduit 2.