JP6235897B2 - Fluid pump and fluid supply device - Google Patents

Description

  The present invention relates to a fluid pump and a fluid supply apparatus.

  For example, the power train of a vehicle is provided with a fluid pump that discharges oil such as hydraulic oil or lubricating oil. In general, the fluid pump is driven by an engine. However, in an idling stop vehicle, a hybrid vehicle, or the like, it is required to stop the engine according to a traveling state. That is, depending on the traveling situation, it is difficult to ensure the hydraulic pressure because the fluid pump is stopped, and therefore, a fluid supply device including a fluid pump driven by an electric motor in addition to a fluid pump driven by an engine has been proposed. (See Patent Document 1).

  By the way, in a fluid supply apparatus including a plurality of fluid pumps, when any one of the fluid pumps is stopped, it is assumed that oil flows from another fluid pump into the stopped fluid pump. Therefore, in the fluid supply device of Patent Document 1, when stopping any one of the fluid pumps, the stop position of the inner rotor is finely adjusted using an electric motor to suppress oil leak of the fluid pump during the stop. . That is, the inner rotor of the fluid pump is stopped at a position where leakage of the fluid pump is suppressed.

JP 2013-68313 A

  However, as in the fluid supply device described in Patent Document 1, finely adjusting the stop position of the inner rotor to suppress leakage of the fluid pump is a factor that complicates the fluid supply device and reduces costs. . For this reason, it is desired to suppress leakage of the fluid pump without complicated control of the electric motor or the like. Further, even in a fluid supply device including one fluid pump, a circuit structure in which oil flows into a stopped fluid pump is also conceivable. Similarly, it is desired to suppress leakage of the fluid pump.

  An object of the present invention is to suppress leakage of a fluid pump.

The fluid pump according to the present invention is housed in a housing and includes an outer rotor having a plurality of internal teeth, an inner rotor having a plurality of external teeth meshing with the internal teeth, a motor rotor connected to the inner rotor, and a radially outer side of the motor rotor. It has an electric motor comprising a stator, a provided towards, the number of teeth of the external teeth the inner rotor comprises the Ri common multiple der between the number of slots said the number of poles the motor rotor stator, the electric motor When the motor rotor is stopped by shutting off the energization of the inner rotor, the tooth tip of the inner tooth and the tooth tip of the outer tooth face each other on an extension line connecting the rotation center of the outer rotor and the rotation center of the inner rotor.

The fluid supply apparatus of the present invention includes a first fluid pump and a second fluid pump connected in parallel, and a fluid supply in which a control mode is executed in which the first fluid pump is stopped and the second fluid pump is driven. The first fluid pump is housed in a housing, and includes an outer rotor having a plurality of internal teeth, an inner rotor having a plurality of external teeth meshing with the internal teeth, a motor rotor coupled to the inner rotor, An electric motor provided with a stator provided radially outward of the motor rotor, and the number of teeth of the external tooth provided in the inner rotor is a common multiple of the number of poles of the motor rotor and the number of slots of the stator. When the electric motor is turned off and the motor rotor is stopped, the rotation center of the outer rotor and the rotation center of the inner rotor are It said tooth tip of the tooth with an extension department and the tooth tip of the outer tooth faces.

  According to the present invention, the number of teeth of the outer rotor included in the inner rotor is a common multiple of the number of poles of the motor rotor and the number of slots of the stator, so that when the electric motor is stopped, the tooth tips of the inner rotor and the outer rotor face each other. Is possible. Thereby, it becomes possible to suppress the leakage of the fluid pump.

It is the schematic which shows an example of the power train mounted in a vehicle. It is the schematic which shows a fluid supply apparatus. It is explanatory drawing which shows the oil supply condition in mechanical pump mode. It is explanatory drawing which shows the oil supply condition in electric pump mode. It is sectional drawing which shows the structure of an electric pump roughly. It is sectional drawing which shows the structure of a pump unit roughly along the AA line of FIG. It is sectional drawing which shows schematically the structure of an electric motor along the BB line of FIG. It is a diagram which shows the change of the clearance between an inner rotor and an outer rotor. (A)-(c) is explanatory drawing which shows the rotation state of an inner rotor and an outer rotor. (A)-(f) is explanatory drawing which shows each pattern in which the tooth-tip of an inner rotor and an outer rotor opposes in an intermediate | middle area | region. (A)-(f) is explanatory drawing which shows the stop pattern of a motor rotor. It is sectional drawing which shows the pump unit of another example. (A)-(f) is explanatory drawing which shows the stop pattern of a pump unit. It is sectional drawing which shows the electric motor of another example. It is explanatory drawing which shows the oil supply condition when a non-return valve fails in mechanical pump mode. It is the schematic which shows the fluid supply apparatus which is other embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic diagram showing an example of a powertrain 10 mounted on a vehicle. As shown in FIG. 1, the power train 10 includes an engine 11 as a power source and a power transmission system 13 that transmits engine power to the drive wheels 12. The power transmission system 13 includes a torque converter 14, a forward / reverse switching mechanism 15, a continuously variable transmission 16, and the like. In addition, in order to supply oil (fluid) for control and lubrication to the torque converter 14, the forward / reverse switching mechanism 15, the continuously variable transmission 16, and the like, the power train 10 according to an embodiment of the present invention. A fluid supply device 17 is provided.

  The fluid supply device 17 has a mechanical oil pump 20 (hereinafter referred to as a mechanical pump) driven by the engine 11 as a second fluid pump. Moreover, the fluid supply apparatus 17 has the electric oil pump 23 (henceforth an electric pump) provided with the electric motor 21 and the pump unit 22 as a 1st fluid pump. The electric pump 23 is provided as a fluid pump according to an embodiment of the present invention. The fluid supply device 17 has a valve unit 24 constituted by a plurality of electromagnetic valves and oil passages. The oil supplied to the valve unit 24 from the mechanical pump 20 or the electric pump 23 is supplied to the forward / reverse switching mechanism 15, the continuously variable transmission 16, or the like via the valve unit 24. Further, a control unit 26 is provided in the fluid supply device 17 to control the engine 11, the valve unit 24, the inverter 25, and the like. The control unit 26 includes a CPU that calculates control signals and the like, a ROM that stores control programs, arithmetic expressions and map data, and a RAM that temporarily stores data. The inverter 25 is an electric device that controls supply of drive current to the electric motor 21.

  The control unit 26 has a mechanical pump mode and an electric pump mode as control modes of the electric pump 23 and the mechanical pump 20. For example, when the engine 11 that drives the mechanical pump 20 is in an operating state, the mechanical pump mode is executed by the control unit 26 and the electric pump 23 is controlled to be stopped. That is, in the mechanical pump mode, the mechanical pump 20 is driven and the electric pump 23 is stopped. On the other hand, when the engine 11 that drives the mechanical pump 20 is in a stopped state, the electric pump mode is set by the control unit 26 and the electric pump 23 is controlled to be in the driving state. That is, in the electric pump mode, the mechanical pump 20 is stopped and the electric pump 23 is driven. Note that a control mode for driving both the mechanical pump 20 and the electric pump 23 may be set.

  FIG. 2 is a schematic view showing the fluid supply device 17. 2, the same members as those shown in FIG. 1 are denoted by the same reference numerals and the description thereof is omitted. As shown in FIG. 2, a suction oil passage 30 is connected to the suction port 20 i of the mechanical pump 20, and a strainer 31 connected to the end of the suction oil passage 30 is accommodated in an oil pan 32. A line pressure path 33 is connected to the discharge port 20 o of the mechanical pump 20. A branch oil passage 34 for supplying oil to the continuously variable transmission 16 or the like is connected to the line pressure passage 33, and a branch oil passage 35 for supplying oil to the torque converter 14 or the like is connected to the line pressure passage 33. The suction oil passage 40 is connected to the suction port 23 i of the electric pump 23, and the end of the suction oil passage 40 is connected to the suction oil passage 30 on the mechanical pump 20 side. A discharge oil passage 41 is connected to the discharge port 23 o of the electric pump 23. A circulation control valve 42 is incorporated in the discharge oil passage 41, and an end portion of the discharge oil passage 41 is connected to the branch oil passage 34 via a check valve 43. Thus, the mechanical pump 20 and the electric pump 23 are connected in parallel. The circulation control valve 42 circulates oil from the discharge port 23o to the suction port 23i when the discharge pressure of the electric pump 23 exceeds a predetermined reference value.

  In addition, an introduction port 45 of a line pressure control valve 44 is connected to the line pressure path 33. The line pressure control valve 44 includes a pressure reducing port 46, and a pressure reducing oil passage 47 is connected to the pressure reducing port 46. In order to adjust the oil flowing through the line pressure path 33 to the target line pressure, the line pressure control valve 44 controls the communication state between the introduction port 45 and the pressure reduction port 46. A lubricating oil passage 51 is connected to the decompression oil passage 47 via a poppet valve 50. The lubricating oil passage 51 includes a plurality of unillustrated branching oil passages that branch toward each lubricating portion of the power transmission system 13, and guides lubricating oil to each lubricating portion. Further, a suction oil passage 53 is connected to the decompression oil passage 47 via a lubrication pressure adjusting valve 52, and an end portion of the suction oil passage 53 is connected to the suction oil passage 30. The lubrication pressure adjusting valve 52 guides oil from the reduced pressure oil passage 47 to the suction oil passage 53 when the pressure in the reduced pressure oil passage 47 exceeds a predetermined reference value. The oil supplied to the lubrication part is guided to the oil pan 32 after the lubrication part is lubricated.

  FIG. 3 is an explanatory view showing an oil supply situation in the mechanical pump mode. FIG. 4 is an explanatory diagram showing an oil supply situation in the electric pump mode. In FIGS. 3 and 4, the flow of oil is shown using white arrows. As shown in FIG. 3, in the mechanical pump mode, since the mechanical pump 20 is driven, oil is supplied from the discharge port 20 o of the mechanical pump 20 to the line pressure path 33. The oil flowing through the line pressure passage 33 is adjusted to the target line pressure by the line pressure control valve 44 and guided to the branch oil passages 34 and 35 toward the continuously variable transmission 16 and the torque converter 14. . Further, since the check valve 43 is provided between the branch oil passage 34 and the discharge oil passage 41, the oil flow from the branch oil passage 34 toward the discharge oil passage 41 is blocked. On the other hand, as shown in FIG. 4, in the electric pump mode, since the electric pump 23 is driven, oil is supplied from the discharge port 23 o of the electric pump 23 to the discharge oil passage 41. The oil flowing through the discharge oil passage 41 passes through the check valve 43 and is guided to the branch oil passage 34. The oil flowing through the branch oil passage 34 is guided to the branch oil passage 35 and the line pressure control valve 44 through the line pressure passage 33.

  Next, the structure of the electric pump 23 will be described. FIG. 5 is a sectional view schematically showing the structure of the electric pump 23. FIG. 6 is a sectional view schematically showing the structure of the pump unit 22 along the line AA in FIG. FIG. 7 is a sectional view schematically showing the structure of the electric motor 21 along the line BB in FIG.

  As shown in FIGS. 5 and 6, the pump unit 22 of the electric pump 23 has a housing 60 in which a suction port 23i and a discharge port 23o are formed. The housing 60 includes a housing main body 62 including the rotor accommodating portion 61 and a housing cover 63 that covers the rotor accommodating portion 61. In the rotor accommodating portion 61 of the housing 60, an outer rotor 64 having the point Co as the rotation center is accommodated rotatably. Further, inside the outer rotor 64, an inner rotor 65 whose center is the point Ci is housed. A motor rotor 66 of the electric motor 21 is connected to the inner rotor 65. As shown in FIG. 7, two permanent magnets 67 and 68 are fixed to the motor rotor 66, and the number of poles, that is, the number of magnetic poles of the motor rotor 66 is “2”. A stator 69 is provided on the outer side of the motor rotor 66 in the radial direction. The stator 69 is provided with three slots 70, and the number of slots of the stator 69 is “3”. Further, a coil 72 for generating a rotating magnetic field is wound around the three teeth 71 provided in the stator 69.

  As shown in FIG. 6, seven inner teeth 73 are formed on the outer rotor 64, and six outer teeth 74 are formed on the inner rotor 65. The inner teeth 73 of the outer rotor 64 and the outer teeth 74 of the inner rotor 65 mesh with each other, and a plurality of pumping chambers 75 are defined between the outer rotor 64 and the inner rotor 65. By rotating the inner rotor 65 in the arrow α direction by the electric motor 21, the outer rotor 64 that meshes with the inner rotor 65 can be rotated in the arrow α direction. Thus, by rotating the outer rotor 64 and the inner rotor 65, the pumping chamber 75 can be moved in the circumferential direction while changing the volume.

  That is, as shown in FIG. 6, in the suction region where the pumping chamber 75 and the suction port 23i communicate with each other, the pumping chamber 75 moves in the circumferential direction while expanding its volume. Thus, in the suction region where the volume of the pumping chamber 75 is expanded, oil is sucked into the pumping chamber 75 from the suction port 23i. On the other hand, in the discharge region where the pumping chamber 75 and the discharge port 23o communicate with each other, the pumping chamber 75 moves in the circumferential direction while reducing its volume. Thus, in the discharge region where the volume of the pumping chamber 75 is reduced, oil is discharged from the pumping chamber 75 to the discharge port 23o.

  By the way, as shown in FIG. 3, the fluid supply device 17 has the check valve 43. However, when a failure state such as a foreign matter biting into the valve body 76 of the check valve 43 occurs, In the pump mode, oil may flow from the branch oil passage 34 to the discharge oil passage 41. That is, the oil discharged from the mechanical pump 20 may flow into the discharge port 23o of the electric pump 23 that stops. Therefore, the electric pump 23 is designed to shut off the oil from the discharge port 23o to the suction port 23i in order to suppress oil leak that is oil leakage during stoppage. That is, as shown in FIG. 6, when the electric pump 23 is stopped, the inner rotor 65 and the outer rotor 64 are located in an intermediate region between the terminal end 77 of the suction port 23 i that opens to the housing 60 and the start end 78 of the discharge port 23 o. Are designed so that the clearance between the rotors 64 and 65 becomes small.

  Hereinafter, a pump structure for suppressing oil leak will be described in detail. FIG. 8 is a diagram showing a change in the clearance between the inner rotor 65 and the outer rotor 64. FIGS. 9A to 9C are explanatory views showing the rotation state of the inner rotor 65 and the outer rotor 64. In FIG. 9, in order to clarify the rotational states of the inner rotor 65 and the outer rotor 64, one of the outer teeth 74 of the inner rotor 65 is marked with “●”, and one of the inner teeth 73 of the outer rotor 64 is “ ○ is marked. Further, the clearance shown in FIG. 8 is the clearance between the tooth tip 74t of the inner rotor 65 and the tooth surface of the outer rotor 64 facing the inner rotor 65 marked with “●” in FIG. Further, the rotation state of FIG. 9A corresponds to the reference A in FIG. 8, the rotation state of FIG. 9B corresponds to the reference B of FIG. 8, and the rotation state of FIG. This corresponds to the code C.

  As indicated by reference signs A and B in FIG. 8, the process of changing the rotation angle of the inner rotor 65 from 0 ° to 90 °, that is, the inner rotor 65 moves from the position of FIG. 9A to the position of FIG. 9B. In the process of rotating, the clearance between the rotors 64 and 65 gradually increases. That is, in the process in which the rotation angle of the inner rotor 65 changes from 0 ° to 90 °, the tooth surface of the outer rotor 64 gradually separates from the tooth tip 74t of the inner rotor 65. On the other hand, as indicated by reference characters B and C in FIG. 8, the process of changing the rotation angle of the inner rotor 65 from 90 ° to 180 °, that is, the inner rotor 65 is moved from the position of FIG. In the process of rotating toward the position, the clearance between the rotors 64 and 65 gradually decreases. That is, in the process in which the rotation angle of the inner rotor 65 changes from 90 ° to 180 °, the tooth surface of the outer rotor 64 gradually approaches the tooth tip 74t of the inner rotor 65. As shown in FIG. 8, when the rotation angle of the inner rotor 65 exceeds 180 °, the clearance starts to increase, and when the rotation angle of the inner rotor 65 exceeds 270 °, the clearance starts to decrease.

  As indicated by reference numeral C in FIG. 8, when the electric pump 23 is stopped, the inner rotor 65 is positioned at a position where the rotation angle is 180 ° in order to reduce the clearance in the intermediate region between the suction region and the discharge region. Need to be stopped. Here, as shown in FIG. 9 (c), when the rotation angle of the inner rotor 65 is 180 °, the tooth tip 74t of the inner rotor 65 and the outer rotor 64 on the extension line L1 connecting the rotation center Co and the rotation center Ci. This is the position where the tooth tip 73t overlaps. That is, by stopping the inner rotor 65 at a rotation angle of 180 °, the tooth tips of the external teeth 74 and the tooth tips of the internal teeth 73 can be opposed to each other in the intermediate region. As shown in FIG. 9C, the extension line L1 connecting the rotation center Co and the rotation center Ci is disposed in an intermediate region between the end 77 of the suction port 23i and the start 78 of the discharge port 23o. Yes. Further, as shown in FIG. 9A, when the rotation angle of the inner rotor 65 is 0 ° (360 °), the tooth tip 74t of the inner rotor 65 is on the extension line L1 connecting the rotation center Co and the rotation center Ci. This is a position where the tooth bottom 73b of the outer rotor 64 overlaps.

  FIGS. 10A to 10F are explanatory diagrams showing patterns in which the rotation angle of the inner rotor 65 is 180 °, that is, patterns in which the tooth tips 73t and 74t of the inner rotor 65 and the outer rotor 64 face each other in the intermediate region. It is. In FIG. 10, numerals 1 to 6 are attached to the external teeth 74 of the inner rotor 65 in order to clarify the rotation state of the inner rotor 65. As shown in FIGS. 10A to 10F, since the inner rotor 65 has six external teeth 74, each time the inner rotor 65 rotates 60 ° (= 360 ° ÷ 6), , The tooth tips 73t and 74t of the rotors 64 and 65 face each other. That is, in order to suppress the oil leak of the electric pump 23, it is necessary to stop the inner rotor 65 in any of the patterns shown in FIGS. 10A to 10F when the electric motor 21 is stopped.

  Therefore, the electric motor 21 that drives the inner rotor 65 includes a motor rotor 66 having the number of poles “2” and a stator 69 having the number of slots “3”. FIGS. 11A to 11F are explanatory views showing stop patterns of the motor rotor 66. FIG. As shown in FIGS. 11A to 11F, in a non-excited state in which the energization to the coil 72 of the electric motor 21 is interrupted, the magnetic attraction force between the motor rotor 66 and the stator 69 is the largest. The motor rotor 66 is stopped. Here, since the least common multiple of the number of poles “2” and the number of slots “3” of the electric motor 21 is “6”, the motor rotor 66 is rotated every 60 ° (= 360 ° ÷ 6). The N pole or S pole of the motor is opposed to the teeth 71, and the magnetic attractive force between the motor rotor 66 and the stator 69 is increased. That is, after the energization of the electric motor 21 is cut off, the motor rotor 66 stops in any of the patterns shown in FIGS.

  That is, the stop pattern of the inner rotor 65 shown in any one of FIGS. 10A to 10F and the stop pattern of the motor rotor 66 shown in any one of FIGS. By fixing the inner rotor 65 and the motor rotor 66, oil leakage in the stopped electric pump 23 can be suppressed. Here, as shown in FIGS. 5 to 7, in the electric pump 23, the stop pattern of the inner rotor 65 shown in FIG. 10A matches the stop pattern of the motor rotor 66 shown in FIG. Thus, the inner rotor 65 and the motor rotor 66 are fixed. Thus, when the motor rotor 66 stops at the position shown in FIG. 11A, the inner rotor 65 stops at the position shown in FIG. When the motor rotor 66 stops at the positions shown in FIGS. 11B, 11C, 11D, 11E, and 11F, the inner rotor 65 is moved to the positions shown in FIGS. It stops at each of the positions d), (e), and (f).

  As described above, after the energization of the electric motor 21 is cut off by adjusting the number of teeth of the inner rotor 65 to the least common multiple of the number of poles and the number of slots of the electric motor 21, the electric motor 21 shown in FIGS. It becomes possible to stop the pump unit 22 at the position shown in any one. Thereby, since the stop position of the inner rotor 65 can be appropriately controlled without adding a rotational position sensor, a control circuit, or the like to the electric pump 23, oil leakage is suppressed while suppressing the cost of the electric pump 23. It becomes possible to do.

  In the above description, the number of teeth of the inner rotor 65 is matched with the least common multiple of the number of poles and the number of slots of the electric motor 21, but the present invention is not limited to this. That is, the outer teeth 74 of the inner rotor 65 may be changed to another number of teeth as long as it is a multiple of the least common multiple of the number of poles and the number of slots, that is, the common multiple of the number of poles and the number of slots. For example, the electric motor 21 shown in FIG. 11 includes a motor rotor 66 having “2” poles and a stator 69 having “3” slots. Therefore, the number of teeth of the inner rotor 65 may be any one of “6”, “12”, “18”, “24”,... Which is a common multiple of the number of poles and the number of slots. As described above, even when the number of teeth of the inner rotor 65 is changed, it is possible to suppress the oil leak during the stop similarly to the electric pump 23 described above.

  Here, FIG. 12 is a sectional view showing a pump unit 80 of another example. 13A to 13F are explanatory diagrams showing stop patterns of the pump unit 80. FIG. In FIG. 12, the same members as those shown in FIG. 6 are denoted by the same reference numerals, and the description thereof is omitted. Further, in FIG. 13, in order to clarify the rotation state of the inner rotor 83, numbers 1 to 6 are given to every other external tooth 84 of the inner rotor 83.

  As shown in FIG. 12, an outer rotor 81 having a point Co as a rotation center is rotatably accommodated in the housing 60, and 13 inner teeth 82 are formed in the outer rotor 81. Further, an inner rotor 83 with the point Ci as the center of rotation is accommodated inside the outer rotor 81, and twelve external teeth 84 are formed on the inner rotor 83. The inner teeth 82 of the outer rotor 81 and the outer teeth 84 of the inner rotor 83 mesh with each other, and a plurality of pumping chambers 85 are defined between the outer rotor 81 and the inner rotor 83. By rotating the inner rotor 83 in the arrow α direction by the electric motor 21, the outer rotor 81 that meshes with the inner rotor 83 can be rotated in the arrow α direction. Thus, by rotating the outer rotor 81 and the inner rotor 83, the pumping chamber 85 can be moved in the circumferential direction while changing the volume.

  Also in the pump unit 80 shown in FIG. 12, as indicated by the symbol C in FIG. 8, in order to reduce the clearance in the intermediate region, it is necessary to stop the inner rotor 83 at a position where the rotation angle is 180 °. . That is, as shown in FIG. 12, when the electric motor 21 is stopped, the tooth tips 82t and 84t of the inner rotor 83 and the outer rotor 81 need to face each other in the intermediate region. Since twelve external teeth 84 are formed on the inner rotor 83 provided in the pump unit 80, each time the inner rotor 83 rotates 30 ° (= 360 ° ÷ 12), the teeth of the rotors 81 and 83 are in the intermediate region. The tips 82t and 84t face each other. That is, as shown in FIGS. 13A to 13F, each time the inner rotor 83 rotates by 60 °, the tooth tips 82t and 84t of the rotors 81 and 83 face each other in the intermediate region.

  For this reason, the stop pattern of the inner rotor 83 shown in any of FIGS. 13A to 13F and the stop pattern of the motor rotor 66 shown in any of FIGS. Further, by fixing the inner rotor 83 and the motor rotor 66, it is possible to suppress oil leakage in the pump unit 80 that is stopped. For example, the inner rotor 83 and the motor rotor 66 are fixed so that the stop pattern of the inner rotor 83 shown in FIG. 13A matches the stop pattern of the motor rotor 66 shown in FIG. Thus, when the motor rotor 66 stops at the position shown in FIG. 11A, the inner rotor 83 stops at the position shown in FIG. When the motor rotor 66 stops at the positions shown in FIGS. 11B, 11C, 11D, 11E, and 11F, the inner rotor 83 is moved to the positions shown in FIGS. It stops at each of the positions d), (e), and (f).

  In the above description, the electric motor 21 includes the motor rotor 66 having the number of poles “2” and the stator 69 having the number of slots “3”. However, the number of poles and the number of slots are not limited to these. Absent. That is, as long as the common multiple of the number of poles and the number of slots matches the number of teeth of the inner rotor, an electric motor having another number of poles and the number of slots may be employed. Here, FIG. 14 is a cross-sectional view showing another example of the electric motor 90. As shown in FIG. 14, four permanent magnets 92 to 95 are fixed to the motor rotor 91, and the number of poles, that is, the number of magnetic poles of the motor rotor 91 is “4”. A stator 96 is provided on the outer side in the radial direction of the motor rotor 91. The stator 96 is provided with six slots 97, and the number of slots of the stator 96 is “6”. Further, a coil 99 for generating a rotating magnetic field is wound around the six teeth 98 provided in the stator 96.

  In the electric motor 90 shown in FIG. 14, since the least common multiple of the number of poles “4” and the number of slots “6” is “12”, the motor rotor 91 rotates 30 ° (= 360 ° ÷ 12). In addition, the N pole or S pole of the motor rotor 91 faces the teeth 98, and the magnetic attractive force between the motor rotor 91 and the stator 96 increases. That is, after the energization of the electric motor 90 is cut off, the motor rotor 91 stops in any one of 12 patterns in which the motor rotor 91 rotates by 30 °. When such an electric motor 90 is employed, as the number of teeth of the inner rotor, any one of “12”, “24”, “36”,... Which is a common multiple of the number of poles and the number of slots is employed. Will be. Thereby, similarly to the electric pump 23 described above, the tooth tips of the rotor can be opposed to each other in the intermediate region, and oil leak of the electric pump can be suppressed.

  Next, FIG. 15 is an explanatory diagram showing an oil supply situation when the check valve 43 fails in the mechanical pump mode. As shown in FIG. 15, when the check valve 43 is not normally shut off in the mechanical pump mode due to the occurrence of a failure state such as a foreign object biting into the valve body 76 of the check valve 43, the branch oil passage Oil flows into the discharge oil passage 41 from 34. At this time, the oil flows into the discharge port 23o of the electric pump 23. As described above, since the clearance of the stopped electric pump 23 is narrowed in the intermediate region, it leaks from the discharge port 23o to the suction port 23i. The amount of oil can be suppressed. In this way, even when the check valve 43 fails, oil leak of the electric pump 23 can be suppressed, and insufficient line pressure can be prevented. That is, it is possible to prevent the oil circulation as shown by the dashed arrows in FIG. 15 and to prevent the line pressure from being insufficient. In addition, oil leakage of the electric pump 23 can be suppressed only by adjusting the number of teeth of the inner rotor 65 to the common multiple of the number of poles and the number of slots of the electric motor 21, thereby reducing the cost of the fluid supply device 17. It becomes possible to do.

  In the above description, the check valve 43 is provided between the discharge oil passage 41 and the branch oil passage 34, but the check valve 43 is reduced from between the discharge oil passage 41 and the branch oil passage 34. May be. Here, FIG. 16 is a schematic view showing a fluid supply apparatus 100 according to another embodiment of the present invention. 16, members similar to those shown in FIG. 3 are given the same reference numerals, and descriptions thereof are omitted. As shown in FIG. 11, a line pressure path 33 is connected to the discharge port 20 o of the mechanical pump 20, and the branch oil path 101 branches from the line pressure path 33. A discharge oil passage 102 is connected to the discharge port 23 o of the electric pump 23. The branch oil passage 101 extending from the discharge port 20 o of the mechanical pump 20 and the discharge oil passage 102 extending from the discharge port 23 o of the electric pump 23 are directly connected. Thus, even when the branch oil passage 101 and the discharge oil passage 102 are directly connected without using the check valve 43, the teeth of the inner rotor 65 are set to a common multiple of the number of poles and the number of slots of the electric motor 21. By combining the numbers, oil leakage of the electric pump 23 can be suppressed.

  It goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. The outer teeth 74 and 84 of the inner rotors 65 and 83 and the inner teeth 73 and 82 of the outer rotors 64 and 81 may have any shape. For example, the outer teeth 74 and 84 and the inner teeth 73 and 82 may be formed by a trochoid curve, and the outer teeth 74 and 84 and the inner teeth 73 and 82 may be formed by an involute curve. Further, the present invention may be applied to a fluid pump including a crescent between the inner rotors 65 and 83 and the outer rotors 64 and 81. The illustrated electric motors 21 and 90 are surface magnet type electric motors having permanent magnets 67 on the surfaces of the motor rotors 66 and 91. However, the present invention is not limited to this, and permanent magnets are embedded in the motor rotor. Such an embedded magnet type electric motor may be used.

  In the above description, the present invention is applied to a vehicle including only the engine 11 as a power source. However, the present invention is not limited to this, and the present invention is applied to a hybrid vehicle including the engine 11 and a motor generator as a power source. May be. In the above description, the fluid supply device 17 is provided in the power train 10, but the present invention is not limited to this, and a fluid supply device may be provided for the engine 11. A supply device may be provided. Needless to say, the fluid discharged from the fluid pump is not limited to oil for control and lubrication, and may be other fluid.

17 Fluid supply device 20 Mechanical oil pump (second fluid pump)
21 Electric motor 23 Electric oil pump (first fluid pump, fluid pump)
23i Suction port 23o Discharge port 60 Housing 64 Outer rotor 65 Inner rotor 66 Motor rotor 69 Stator 73 Inner teeth 73t Tooth tips 74 Outer teeth 74t Tooth tips 77 Terminal end 81 Outer rotor 82 Inner teeth 82t Tooth tips 83 Inner rotor 84 Outer teeth 84t Tooth tips 90 Electric Motor 91 Motor rotor 96 Stator Ci Rotation center Co Rotation center L1 Extension line

Claims (4)

An outer rotor housed in a housing and having a plurality of internal teeth;
An inner rotor having a plurality of external teeth meshing with the internal teeth;
An electric motor comprising: a motor rotor coupled to the inner rotor; and a stator provided radially outward of the motor rotor;
Have
The inner rotor tooth number of the outer teeth provided in the Ri common multiple der between the number of slots said the number of poles the motor rotor stator,
When the energization of the electric motor is cut off and the motor rotor is stopped, the tooth tip of the inner tooth and the tooth tip of the outer tooth are on an extension line connecting the rotation center of the outer rotor and the rotation center of the inner rotor. Opposite, fluid pump. The fluid pump according to claim 1.
The fluid pump, wherein an extension line connecting the rotation center of the outer rotor and the rotation center of the inner rotor is disposed between a terminal end of the suction port opening in the housing and a start end of the discharge port. A fluid supply device including a first fluid pump and a second fluid pump connected in parallel, wherein a control mode is executed in which the first fluid pump is stopped and the second fluid pump is driven,
The first fluid pump includes
An outer rotor housed in a housing and having a plurality of internal teeth;
An inner rotor having a plurality of external teeth meshing with the internal teeth;
An electric motor comprising: a motor rotor coupled to the inner rotor; and a stator provided radially outward of the motor rotor;
Have
The inner rotor tooth number of the outer teeth provided in the Ri common multiple der between the number of slots said the number of poles the motor rotor stator,
When the energization of the electric motor is cut off and the motor rotor is stopped, the tooth tip of the inner tooth and the tooth tip of the outer tooth are on an extension line connecting the rotation center of the outer rotor and the rotation center of the inner rotor. Opposing fluid supply device. The fluid supply apparatus according to claim 3 , wherein
The fluid supply device, wherein an extension line connecting the rotation center of the outer rotor and the rotation center of the inner rotor is disposed between a terminal end of the suction port opening in the housing and a start end of the discharge port.

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