JP2019167863A - Driving device for oil pump - Google Patents

Abstract

To provide a driving device for an oil pump to supply lubricating oil to a drive transmission system even when the electric oil pump fails.SOLUTION: The driving device for the oil pump to supply lubricating oil to the drive transmission system which transmits the power of a power source, includes an electric motor for rotating a rotor of the oil pump, a one-way clutch having a first rotary member linked with the rotor and a second rotary member to be driven by the drive transmission system for, when the rotation speed of the second rotary member is higher than the rotation speed of the first rotary member, transmitting the rotation force of the second rotary member to the first rotary member, and a control part for controlling the electric motor to set the rotation speed of the first rotary member to be equal to or higher than the rotation speed of the second rotary member.SELECTED DRAWING: Figure 2

Description

  The present disclosure relates to an oil pump drive device.

  2. Description of the Related Art Conventionally, an oil pump for supplying lubricating oil to a drive transmission system such as a transmission or transfer mounted on a vehicle is known (for example, see Patent Document 1).

  The oil pump includes a mechanical oil pump that is driven by receiving power from a camshaft or a crankshaft, or an electric oil pump that is driven by receiving power from an electric motor.

  The mechanical oil pump has rotational resistance of the camshaft or the like by the amount of power received from the camshaft or the like.

  On the other hand, since the electric oil pump does not receive power from the camshaft or the like, the rotational resistance of the camshaft or the like does not occur.

JP 2009-162250 A

  By the way, when an electric oil pump fails, it becomes difficult to supply lubricating oil to a drive transmission system, and malfunctions, such as an inability to travel, may occur.

  There is a need for a failsafe system that can supply lubricating oil to a drive transmission system even when an electric oil pump fails.

  An object of the present disclosure is to provide an oil pump drive device capable of supplying lubricating oil to a drive transmission system even when an electric oil pump fails.

An oil pump drive device according to an aspect of the present disclosure includes:
An oil pump drive device for supplying lubricating oil to a drive transmission system for transmitting power from a power source,
An electric motor for rotating the rotor of the oil pump;
A first rotating member that is linked to the rotor, and a second rotating member that is driven by the drive transmission system, and the rotational speed of the second rotating member is higher than the rotational speed of the first rotating member; A one-way clutch that transmits the rotational force of the second rotating member to the first rotating member;
A control unit that controls the electric motor so that the rotation speed of the first rotation member is equal to or higher than the rotation speed of the second rotation member;
Is provided.

  According to the present disclosure, even when the electric oil pump fails, the lubricating oil can be supplied to the drive transmission system.

The figure which shows schematically the structure of the vehicle containing the drive device of the oil pump which concerns on one embodiment of this indication. The figure which shows schematically the structure of the drive device of the oil pump which concerns on this Embodiment. The flowchart which shows operation | movement of the drive device of the oil pump which concerns on this Embodiment.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

  First, a configuration of a vehicle including an oil pump drive device according to an embodiment of the present disclosure will be described.

  In FIG. 1, the X axis is depicted. The left and right direction in FIG. 1 is referred to as X direction, the left direction is referred to as “X1 direction”, “left direction” or “left side”, and the right direction is referred to as “X2 direction”, “right direction” or “right side”. The direction away from the X axis is referred to as “centrifugal direction” or “centrifugal side”. The direction toward the X axis is called “centripetal direction” or “centripetal side”.

  The vehicle has a transfer 1 (corresponding to the “drive transmission system” of the present invention) that is a mechanism for distributing the output of an internal combustion engine (engine, not shown, corresponding to the “power source” of the present invention) to the drive wheels. Is provided. The transfer 1 has a housing 2 and an output shaft 3. The housing 2 rotatably supports the output shaft 3 via a shaft support (not shown). The output shaft 3 is disposed along the X axis. The output shaft 3 is connected to a crankshaft (not shown) of the engine via a transmission (not shown). In the present embodiment, the output shaft 3 is a mechanical pump shaft 20 (described later).

  For example, the oil pump 10 supplies lubricating oil to the shaft support portion of the transfer 1. The oil pump 10 is, for example, a trochoid oil pump. The oil pump 10 includes a pump casing portion 11, an inner rotor 12 (corresponding to the “first rotating member” of the present invention), and an outer rotor 13.

  The pump casing part 11 has a cylindrical part 11a that covers the output shaft 3 from the centrifugal direction. The left end of the cylindrical portion 11a is closed by the disc portion 11b. The right end of the cylindrical part 11a is open. The cylindrical portion 11 a houses the inner rotor 12 and the outer rotor 13. The cylindrical part 11a supports the outer rotor 13 rotatably.

  The inner rotor 12 is disposed on the centripetal side of the outer rotor 13. The inner rotor 12 is disposed so as to mesh with the outer rotor 13.

  A pump chamber (not shown) is formed between the inner rotor 12 and the outer rotor 13. A suction passage 15 and a discharge passage 16 are connected to the pump chamber. The suction passage 15 communicates with a lubricating oil reservoir (not shown). The discharge path 16 communicates with the hollow hole 21 of the mechanical pump shaft 20. When the inner rotor 12 rotates in one direction (for example, a clockwise direction when viewed from the X1 direction, hereinafter simply referred to as “clockwise direction”), the pump chamber repeatedly expands and contracts. Thereby, the lubricating oil in the lubricating oil reservoir is sucked into the pump chamber from the suction passage 15, and the lubricating oil in the pump chamber is discharged from the discharge passage 16 to the hollow hole 21.

  FIG. 2 is a diagram schematically showing the configuration of the drive device 100 of the oil pump 10 according to the present embodiment. As shown in FIG. 2, the drive device 100 of the oil pump 10 includes a mechanical pump shaft 20, an electric motor 30, a one-way clutch 40, and a control unit 50 (see FIG. 1).

  The mechanical pump shaft 20 is provided integrally with the output shaft 3. For this reason, the rotational speed of the mechanical pump shaft 20 (output shaft) varies according to the vehicle speed and the rotational speed of the drive wheels.

  The electric motor 30 includes a motor casing portion 31, a rotor 32, and a stator 33. The electric motor 30 is, for example, a reluctance motor in which the rotor 32 is composed only of a ferromagnetic iron core. In the reluctance motor, torque (reluctance torque) generated by the magnetic attraction force between the pole due to the rotating magnetic field of the stator 33 and the salient pole of the rotor 32 is used. The use of the reluctance motor has the following advantages. Since no permanent magnet is used for the rotor 32, the load applied to the output shaft 3 from the rotor 32 side is small during fail safe (when the inner rotor 12 is rotated by the output shaft 3). Further, durability is improved. Further, the size can be reduced.

  The motor casing portion 31 is disposed on the right side (X2 direction) of the pump casing portion 11. The motor casing portion 31 has an annular portion 31a that covers the output shaft 3 from the centrifugal direction. The right end of the annular portion 31a is closed by the disc portion 31b. The left end of the annular part 31a is open.

  The annular portion 31 a accommodates the rotor 32 and the stator 33. The left end edge of the annular portion 31a and the right end edge of the cylindrical portion 11a are coupled to each other.

  The rotor 32 is configured to be rotatable integrally with the inner rotor 12. The rotor 32 extends the inner rotor 12 in the right direction (X2 direction). Hereinafter, the rotor 32 may be referred to as the inner rotor 12.

  The stator 33 is disposed on the centrifugal side of the inner rotor 12 (rotor 32). The stator 33 is fixed to the annular portion 31a.

  The one-way clutch 40 includes a first rotating member that is linked to the inner rotor 12 and a second rotating member that is driven by the transfer 1. In the present embodiment, the first rotating member is the inner rotor 12. In addition, the second rotating member is an output shaft 3.

  Specifically, the one-way clutch 40 causes relative rotation of the output shaft 3 relative to the inner rotor 12 in one direction (clockwise direction as viewed from the X1 direction, hereinafter simply referred to as “clockwise direction”) to the inner rotor 12. introduce. Further, the one-way clutch 40 is an output shaft 3 that rotates relative to the inner rotor 12 in a direction opposite to one direction (counterclockwise direction when viewed from the X1 direction, hereinafter simply referred to as “counterclockwise direction”). To idle.

  As the one-way clutch 40, a known one-way clutch such as a sprag type, a roller type, or a ratchet type is used. As the one-way clutch 40, a one having a sliding resistance of the output shaft 3 as small as possible during idling is preferable.

  As described above, the rotational speed of the output shaft 3 varies according to the vehicle speed. In the following description, the rotation direction of the output shaft 3 when the vehicle moves forward is clockwise, and the rotation direction of the output shaft 3 when the vehicle moves backward is counterclockwise. The control unit 50 acquires vehicle speed information. In addition, vehicle speed information is calculated | required based on the pulse signal generated in proportion to the rotation speed of the output shaft 3, for example. The pulse signal is detected by a vehicle speed sensor.

  When the vehicle moves forward, the output shaft 3 rotates in one direction (clockwise direction). When rotating the inner rotor 12 in one direction by the electric motor 30, if the rotational speed R1 of the inner rotor 12 is lower than the rotational speed R2 of the output shaft 3 (R1 <R2), a load is applied from the inner rotor 12 to the output shaft 3. End up.

  Therefore, in the present embodiment, the control unit 50 causes the inner rotor 12 to rotate in one direction (clockwise direction) based on the rotational speed R2 of the output shaft 3 when the vehicle is moving forward. The electric motor 30 is controlled to rotate at a rotational speed R1 (≧ R2) equal to or higher than R2. When the inner rotor 12 rotates in one direction, the oil pump 10 can be operated. In this case, since the one-way clutch 40 idles with respect to the output shaft 3, the inner rotor 12 or the like does not become the rotational resistance of the output shaft 3.

  When the vehicle moves backward, the output shaft 3 rotates in a direction opposite to one direction (counterclockwise direction). If the inner rotor 12 is rotated in one direction by the electric motor 30, no load is applied to the output shaft 3 from the inner rotor 12.

  Therefore, in the present embodiment, the control unit 50 controls the electric motor 30 so as to rotate the inner rotor 12 in one direction (clockwise direction) at a predetermined rotational speed when the vehicle is moving backward. Thus, even when the vehicle is moving backward, the oil pump 10 can be operated by rotating the inner rotor 12 in one direction (clockwise direction). Even in this case, the one-way clutch 40 idles with respect to the output shaft 3, so that the inner rotor 12 and the like do not serve as rotational resistance of the output shaft 3.

  When the electric motor 30 fails, it becomes impossible for the electric motor 30 to rotate the inner rotor 12 in one direction (clockwise direction). However, when the vehicle moves forward, the output shaft 3 rotates in one direction (clockwise direction). Therefore, rotation of the output shaft 3 in one direction (clockwise direction) relative to the inner rotor 12 can be transmitted to the inner rotor 12 via the one-way clutch 40. Thereby, the inner rotor 12 can be rotated in one direction. As a result, the oil pump 10 can be operated. As described above, even when the electric motor 30 fails, the operation of the oil pump 10 can be continued.

  Next, operation | movement of the drive device 100 of the oil pump 10 is demonstrated with reference to FIG. FIG. 3 is a flowchart showing the operation of the driving device 100 of the oil pump 10 according to the present embodiment. This flow starts when the engine is started and ends when the engine is stopped. In the following description, only the time when the vehicle moves forward is described, and the description when the vehicle moves is omitted.

  In step S100, the control unit 50 acquires vehicle speed information.

  In step S110, the control unit 50 controls the electric motor 30 to rotate the inner rotor 12 in one direction (clockwise direction) at a rotational speed higher than the rotational speed of the output shaft 3 based on the vehicle speed information. .

  As described above, according to drive device 100 of oil pump 10 according to the present embodiment, electric motor 30 that rotates inner rotor 12 of oil pump 10, output shaft 3 of transfer 1, and rotation of output shaft 3. When the number is higher than the rotational speed of the inner rotor 12, the one-way clutch 40 that transmits the rotational force of the output shaft 3 to the inner rotor 12, and the rotational speed of the inner rotor 12 to be greater than or equal to the rotational speed of the output shaft 3, And a control unit 50 that controls the electric motor 30 so that the one-way clutch 40 rotates idly. As a result, even when the electric motor 30 fails, the rotation of the output shaft 3 can be transmitted to the inner rotor 12 via the one-way clutch 40. Thereby, the oil pump 10 can be operated. As described above, even when the electric motor 30 has failed, the operation of the oil pump 10 can be continued, so that it is possible to avoid the occurrence of problems such as inability to travel.

  Further, since the control unit 50 controls the electric motor 30 so that the rotational speed of the inner rotor 12 is equal to or higher than the rotational speed of the output shaft 3, the one-way clutch 40 rotates idly with respect to the output shaft 3. As a result, the inner rotor 12 or the like does not become the rotational resistance of the output shaft 3. For this reason, fuel consumption can be improved.

  In the above embodiment, the mechanical pump shaft 20 is provided integrally with the output shaft 3. Thereby, size reduction of the drive device 100 can be achieved.

  In the drive device 100 of the oil pump 10 according to the above embodiment, the mechanical pump shaft 20 is disposed coaxially with the output shaft 3 of the transfer 1, but the present invention is not limited to this. For example, the mechanical pump shaft 20 is Alternatively, the output shaft 3 may be disposed on a different shaft and connected to the output shaft 3 via an endless belt, a chain, or the like. At this time, for example, the mechanical pump shaft 20 is connected to the inner rotor 12, the one-way clutch 40 is arranged coaxially with the output shaft 3, and the mechanical pump shaft 20 is connected to the output shaft 3 via the endless belt and the one-way clutch 40. .

  Further, as the rotational speed of the output shaft 3, for example, the rotational speed of the power source or the driving wheel is detected by a sensor, and the rotational speed of the output shaft is calculated using the detected value. It may be used. Further, a rotational speed obtained by providing a sensor on the output shaft and detecting it may be used.

  Moreover, in the drive device 100 of the oil pump 10 in the above-described embodiment, the transfer 1 is cited as an object to be supplied with lubrication. However, the present invention is not limited to this, and may be a transmission, for example. In addition, the application range of drive device 100 of oil pump 10 in the above embodiment is not limited to a vehicle.

  In addition, each of the above-described embodiments is merely an example of actualization in carrying out the present invention, and the technical scope of the present invention should not be construed as being limited thereto. That is, the present invention can be implemented in various forms without departing from the gist or the main features thereof.

  The drive device 100 of the oil pump 10 of the present disclosure is useful as a vehicle lubrication system that is required to supply lubricating oil to a drive transmission system even when the electric oil pump fails.

DESCRIPTION OF SYMBOLS 1 Transfer 2 Housing 3 Output shaft 10 Oil pump 11 Pump casing part 11a Cylindrical part 11b Disk part 12 Inner rotor 13 Outer rotor 15 Intake path 16 Discharge path 20 Mechanical pump shaft 30 Electric motor 31 Motor casing part 31a Annular part 31b Disk Part 32 Rotor 33 Stator 40 One-way clutch 50 Control part 100 Drive device

Claims (4)

An oil pump drive device for supplying lubricating oil to a drive transmission system for transmitting power from a power source,
An electric motor for rotating the rotor of the oil pump;
A first rotating member that is linked to the rotor, and a second rotating member that is driven by the drive transmission system, and the rotational speed of the second rotating member is higher than the rotational speed of the first rotating member; A one-way clutch that transmits the rotational force of the second rotating member to the first rotating member;
A control unit that controls the electric motor so that the rotation speed of the first rotation member is equal to or higher than the rotation speed of the second rotation member;
Comprising
Oil pump drive unit. The control unit controls the electric motor based on the number of rotations of the second rotating member detected by a sensor.
The oil pump drive device according to claim 1. The second rotating member is disposed coaxially with the output shaft of the drive transmission system.
The oil pump drive device according to claim 1 or 2.   The oil pump drive device according to claim 3, wherein the second rotating member is the output shaft.