JP6802725B2 - Vehicle oil pump drive - Google Patents

Description

The present invention relates to a vehicle oil pump drive device.

Among vehicles such as automobiles that travel by using an engine as a drive source, there are vehicles equipped with an oil pump that is driven by the rotation of the output shaft of the engine. Such an oil pump is connected to the output shaft of the engine via a gear mechanism, and is rotationally driven when the output shaft of the engine rotates to discharge oil. The oil discharged by the oil pump is supplied to the transmission as, for example, hydraulic pressure or lubricating oil (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2015-161317

Here, when the oil pump is connected to the output shaft of the engine, the vehicle travels not only when the vehicle is driven by the torque output from the engine but also when the torque output from the engine is stopped. The oil pump is driven even when the coast is running. Therefore, although the amount of oil supplied to the transmission may be smaller during the coastal drive than during the drive drive, the oil pump is driven in the same manner as during the drive drive, resulting in friction (mechanical friction loss). Becomes larger.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is a new and improved vehicle oil capable of reducing friction caused by driving an oil pump and improving fuel efficiency. To provide a pump drive.

In order to solve the above problems, according to a certain viewpoint of the present invention, in an oil pump drive device of a vehicle including an oil pump that is driven by rotation of the output shaft of the engine, the output shaft of the engine and the oil pump are driven. A second torque transmission mechanism that connects the shafts at the first gear ratio and a second gear ratio that connects the output shaft of the engine and the drive shaft of the oil pump at a second gear ratio different from the first gear ratio. A torque transmission mechanism is provided, the first torque transmission mechanism has a first clutch, the second torque transmission mechanism has a second clutch, and the first clutch and the second clutch are common. Provided is a vehicle oil pump drive, which is a clutch that switches the transmission or interruption of torque by an axial load generated by a torque input to the helical gear of the vehicle.

When one of the first clutch and the second clutch is in the torque transmission state, the other clutch may be in the torque cutoff state.

While the vehicle is running, the first clutch is in the torque transmission state when the engine outputs torque, while the second clutch is in the torque cutoff state, and when the engine does not output torque, the second clutch transmits torque. On the other hand, the first clutch may be in the torque cutoff state.

The first gear ratio may be larger than the second gear ratio.

When an axial load in one direction is generated by torque input to the helical gear, the first clutch is engaged while the second clutch is disengaged, and the torque input to the helical gear causes an axial load in the other direction. The first clutch may be disengaged while the second clutch may be engaged.

The first torque transmission mechanism may include a first one-way clutch in the torque transmission path from the first clutch to the drive shaft of the oil pump.

The second torque transmission mechanism may include a second one-way clutch in the torque transmission path from the second clutch to the drive shaft of the oil pump.

The helical gear is provided in a torque transmission path that transmits torque from the output shaft of the engine to the rotating shaft on the drive wheel side so that an axial load is generated in one direction when the engine outputs torque while the vehicle is running. Torque is input to the helical gear, and torque is input to the helical gear so that an axial load is generated in another direction when the engine does not output torque.

As described above, according to the present invention, it is possible to reduce friction caused by driving the oil pump and improve fuel efficiency.

It is explanatory drawing which shows the structural example of the oil pump drive device which concerns on 1st Embodiment of this invention. It is sectional drawing which shows the structural example of the 1st clutch and the 2nd clutch of the oil pump drive device which concerns on the same embodiment. It is explanatory drawing which shows the transmission path of the oil pump drive torque at the time of a drive running. It is explanatory drawing which shows the transmission path of the oil pump drive torque at the time of coast running. It is explanatory drawing which shows the structural example of the oil pump drive device which concerns on the modification of this embodiment. It is explanatory drawing which shows the structural example of the oil pump drive device which concerns on 2nd Embodiment of this invention.

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In the present specification and the drawings, components having substantially the same functional configuration are designated by the same reference numerals, so that duplicate description will be omitted.

<< 1. First Embodiment >>
<1-1. Overall configuration example of oil pump drive device>
An example of the overall configuration of the oil pump drive device 50 according to the first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic view showing an oil pump drive device 50 according to the present embodiment. In FIG. 1, the oil pump drive device 50 is provided in a torque transmission path for transmitting torque from the output shaft 11 of the engine 10 to the drive shaft 23 connected to the drive wheels 25. More specifically, the oil pump drive device 50 is a device that drives the oil pump 51 as the output shaft 11 of the engine 10 rotates, and shifts the output shaft 11 of the engine 10 and the input rotational torque to a predetermined speed. It is interposed between the input shaft 21 of the transmission 20 which is converted by the ratio and output to the drive shaft 23 side.

The output shaft 11 of the engine 10 is connected to the input shaft 21 of the transmission 20 via the first helical gear 61, the second helical gear 83, and the third helical gear 63. The transmission 20 converts the rotation speed of the input shaft 21 at a predetermined gear ratio and outputs it to the drive shaft 23 side. The transmission 20 may be configured to include a stepped speed change mechanism, or may be configured to include a continuously variable transmission (CVT).

The transmission 20 may be provided with a torque transmission mechanism (not shown) such as a torque converter or a clutch. Further, a torque transmission mechanism (not shown) such as a transfer clutch or a differential gear may be provided between the transmission 20 and the drive shaft 23. Further, the oil pump drive device 50 may be applied to a hybrid vehicle in which a drive motor or a generator is connected in the middle of a torque transmission path from the engine 10 to the drive wheels 25.

The oil pump 51 driven by the oil pump drive device 50 is, for example, a gear pump, and discharges oil by rotationally driving a gear provided on a pump drive shaft 53 that drives the oil pump 51.

The oil pump drive device 50 mainly includes a first helical gear 61, a second helical gear 83, a third helical gear 63, a first clutch 71, a second clutch 75, a first drive gear 93, and a second drive gear. It includes 113, a first driven gear 55, and a second driven gear 57. The first helical gear 61 is provided coaxially with the output shaft 11 of the engine 10, and the third helical gear 63 is provided coaxially with the input shaft 21. The second helical gear 83 is provided coaxially with the clutch input shaft 81. The first drive gear 93 is provided coaxially with the first clutch output shaft 91, and the second drive gear 113 is provided coaxially with the second clutch output shaft 111. Both the first driven gear 55 and the second driven gear 57 are provided coaxially with the pump drive shaft 53. In the example shown in FIG. 1, the first driven gear 55 and the second driven gear 57 are provided at both ends of the pump drive shaft 53, but the arrangement positions are limited as long as they are provided coaxially with the pump drive shaft 53. Not done.

The first helical gear 61 and the second helical gear 83 are meshed with each other, and the second helical gear 83 and the third helical gear 63 are meshed with each other. The first helical gear 61 provided on the output shaft 11 of the engine 10 and the third helical gear 63 provided on the input shaft 21 are configured so as not to move in the axial direction. On the other hand, the second helical gear 83 provided on the clutch input shaft 81 is configured to be movable in the axial direction together with the clutch input shaft 81. The first clutch 71 and the second clutch 75 are clutches that switch torque transmission or disconnection according to an axial load generated by torque input to a common second helical gear 83.

The first clutch 71 switches the transmission or disconnection of torque between the clutch input shaft 81 and the first clutch output shaft 91. When the first clutch 71 is connected, torque is transmitted from the clutch input shaft 81 to the first clutch output shaft 91, while when the first clutch 71 is released, the clutch input shaft 81 and the first clutch output shaft 91 The transmission of torque between is cut off. The first drive gear 93 and the first driven gear 55 are meshed with each other, and the rotational torque transmitted to the first clutch output shaft 91 passes through the first drive gear 93 and the first driven gear 55. It is transmitted to the pump drive shaft 53. That is, the clutch input shaft 81, the first clutch 71, the first clutch output shaft 91, the first drive gear 93, the first driven gear 55, and the pump drive shaft 53 allow the clutch input shaft 81 to the pump drive shaft 53. A first torque transmission path is configured to transmit torque to the vehicle.

The second clutch 75 switches torque transmission or disconnection between the clutch input shaft 81 and the second clutch output shaft 111. When the second clutch 75 is connected, torque is transmitted from the clutch input shaft 81 to the second clutch output shaft 111, while when the second clutch 75 is released, the clutch input shaft 81 and the second clutch output shaft 111 The transmission of torque between is cut off. The second drive gear 113 and the second driven gear 57 are meshed with each other, and the rotational torque transmitted to the second clutch output shaft 111 is transmitted via the second drive gear 113 and the second driven gear 57. It is transmitted to the pump drive shaft 53. That is, the clutch input shaft 81, the second clutch 75, the second clutch output shaft 111, the second drive gear 113, the second driven gear 57, and the pump drive shaft 53 allow the clutch input shaft 81 to the pump drive shaft 53. A second torque transmission path is configured to transmit torque to the vehicle.

The first gear ratio α when rotation is transmitted from the first drive gear 93 to the first driven gear 55 in the first torque transmission path (number of teeth R1 / first driven of the first drive gear 93). The number of teeth R2 of the gear 55 is the second gear ratio β (second drive gear 113) when rotation is transmitted from the second drive gear 113 to the second driven gear 57 in the second torque transmission path. The number of teeth R3 / the number of teeth R4) of the second driven gear 57 is larger than that of. For example, when the rotational torque is transmitted through the first torque transmission path, the rotation speed of the pump drive shaft 53 is higher than the rotation speed of the clutch input shaft 81, while the rotation is performed through the second torque transmission path. When torque is transmitted, the rotation speed of the pump drive shaft 53 may be configured to be lower than the rotation speed of the clutch input shaft 81.

The second helical gear 83 and the clutch input shaft 81 are thrust axially moved by the axial load generated when the rotational torque is transmitted from the first helical gear 61 or the third helical gear 63 to the second helical gear 83. .. In a state where torque is output from the engine 10, rotational torque is transmitted from the first helical gear 61 to the second helical gear 83 and from the second helical gear 83 to the third helical gear 63, and the drive wheels 25 rotate. At this time, the first helical gear 61, the second helical gear 83, and the third helical gear are thrust so that the second helical gear 83 and the clutch input shaft 81 are thrust moved to the first drive gear 93 side (right side in the drawing). 63 is configured.

Further, when the torque output from the engine 10 is stopped and the drive wheels 25 are rotating, the third helical gear 63 to the second helical gear 83 and the second helical gear 83 to the first helical gear 61 are changed. The rotational torque is transmitted, and a braking force is generated on the drive wheels 25 due to the rotational resistance of the engine 10 and the like. At this time, the first helical gear 61, the second helical gear 83, and the third helical gear are thrust so that the second helical gear 83 and the clutch input shaft 81 are thrust moved to the second drive gear 113 side (left side in the drawing). 63 is configured.

That is, in the oil pump drive device 50, when a torque input to the second helical gear 83 causes an axial load on the first drive gear 93 side, the first clutch 71 is connected while the second clutch 71 is connected. Clutch 75 is disengaged. Further, when a torque input to the second helical gear 83 causes an axial load on the second drive gear 113 side, the second clutch 75 is connected while the first clutch 71 is disconnected. .. As a result, the oil pump 51 is transmitted via either the first torque transmission path or the second torque transmission path when the output shaft 11 of the engine 10 and the input shaft 21 of the transmission 20 are rotating. It is driven by the rotational torque and discharges oil.

<1-2. Clutch mechanism configuration example>
A specific configuration example of the clutch mechanism including the first clutch 71 and the second clutch 75 of the oil pump drive device 50 according to the present embodiment will be described with reference to FIG. FIG. 2 is a cross-sectional view showing an example of the clutch mechanism.

The clutch input shaft 81 provided with the second helical gear 83 on the outer peripheral surface is rotatably supported by bearings 77 and 79 with respect to the housing and the like. The tooth surface 83a of the second helical gear 83 meshes with the tooth surface of the first helical gear 61 and the tooth surface of the third helical gear 63.

A first piston 85 is fixed to the outer peripheral surface of the clutch input shaft 81 on one end side. The first piston 85 is capable of pressing the first pressure plate 87 provided on the outer periphery of the end portion of the clutch input shaft 81 on one end side toward one end side. A second piston 105 is fixed to the outer peripheral surface of the clutch input shaft 81 on the other end side. The second piston 105 is capable of pressing the second pressure plate 107 provided on the outer periphery of the other end of the clutch input shaft 81 toward the other end. The first piston 85, the second piston 105, the first pressure plate 87 and the second pressure plate 107 may be fixed to the clutch input shaft 81 by, for example, spline coupling.

The first pressure plate 87 provided at one end of the clutch input shaft 81 faces the first pressure receiving plate 89. The first pressure receiving plate 89 is fixed to the first pressure receiving case 95. The first pressure receiving case 95 is fixed to the end of the first clutch output shaft 91 located on the clutch input shaft 81 side. The first pressure receiving case 95 is configured to surround the periphery of one end of the clutch input shaft 81 provided with the first pressure plate 87 in a part thereof, and the first pressure receiving plate is formed on the inner circumference thereof. 89 is fixed.

The first clutch output shaft 91 is rotatably supported by a bearing (not shown) on one end side of the clutch input shaft 81. The first clutch output shaft 91 is provided coaxially with the clutch input shaft 81. A first drive gear 93 is provided on the outer peripheral surface of the first clutch output shaft 91. The tooth surface 93a of the first drive gear 93 meshes with the tooth surface of the first driven gear 55. For example, the number of teeth R1 of the first drive gear 93 is larger than the number of teeth R2 of the first driven gear 55, and when the rotational torque is transmitted from the first drive gear 93 to the first driven gear 55. The number of revolutions may increase. However, as long as the first gear ratio α is larger than the second gear ratio β, the magnitude relationship between the number of teeth R1 of the first drive gear 93 and the number of teeth R2 of the first driven gear 55 is not limited.

The second pressure plate 107 provided at the other end of the clutch input shaft 81 faces the second pressure receiving plate 109. The second pressure receiving plate 109 is fixed to the second pressure receiving case 115. The second pressure receiving case 115 is fixed to the end of the second clutch output shaft 111 located on the clutch input shaft 81 side. The second pressure receiving case 115 is configured to surround the periphery of one end of the clutch input shaft 81 provided with the second pressure plate 107 in a part thereof, and the second pressure receiving plate is formed on the inner circumference thereof. 109 is fixed.

The second clutch output shaft 111 is rotatably supported by a bearing (not shown) on one end side of the clutch input shaft 81. The second clutch output shaft 111 is provided coaxially with the clutch input shaft 81. A second drive gear 113 is provided on the outer peripheral surface of the second clutch output shaft 111. The tooth surface 113a of the second drive gear 113 meshes with the tooth surface of the second driven gear 57. For example, the number of teeth R3 of the second drive gear 113 is smaller than the number of teeth R4 of the second driven gear 57, and when the rotational torque is transmitted from the second drive gear 113 to the second driven gear 57. The number of revolutions may decrease. However, as long as the second gear ratio β is smaller than the first gear ratio α, the magnitude relationship between the number of teeth R3 of the second drive gear 113 and the number of teeth R4 of the second driven gear 57 is not limited.

As described above, the clutch input shaft 81 having the second helical gear 83 can move in the axial direction together with the second helical gear 83. In the present embodiment, in a state where the torque is output from the engine 10, the torque input to the second helical gear 83 causes an axial load to the first drive gear 93 side, and the clutch input shaft 81 is the first. Thrust moves to the drive gear 93 side of 1. As a result, the first piston 85 presses the first pressure plate 87, so that the first pressure plate 87 is pressed against the first pressure receiving plate 89 and the first clutch 71 is connected. .. At this time, since the second piston 105 does not press the second pressure plate 107, the second clutch 75 is opened.

On the other hand, when the torque output from the engine 10 is stopped and the drive wheels 25 are rotating, the torque input to the second helical gear 83 causes an axial load on the second drive gear 113 side. As a result, the clutch input shaft 81 is thrust-moved to the second drive gear 113 side. As a result, the second piston 105 presses the second pressure plate 107, so that the second pressure plate 107 is pressed against the second pressure receiving plate 109 and the second clutch 75 is connected. .. At this time, since the first piston 85 does not press the first pressure plate 87, the first clutch 71 is opened.

<1-3. Action of oil pump drive>
Next, the operation of the oil pump drive device 50 according to the present embodiment will be described. FIG. 3 shows how the drive torque is transmitted to the oil pump 51 when the vehicle is driving, and FIG. 4 shows how the drive torque is transmitted to the oil pump 51 when the vehicle is running on the coast. Shown.

As shown in FIG. 3, during drive driving in which the drive wheels 25 are rotated by the torque output from the engine 10, the first clutch 71 is connected by the axial load generated by the torque input to the second helical gear 83. On the other hand, the second clutch 75 is released. Therefore, a part of the torque output from the engine 10 is transmitted to the pump drive shaft 53 as the drive torque of the oil pump 51 via the first torque transmission path to drive the oil pump 51. In this case, the first gear ratio α when the rotation is transmitted from the first drive gear 93 to the first driven gear 55 is relatively large, for example, the rotation speed is increased and transmitted.

When driving a vehicle by outputting torque from the engine 10, it is necessary to supply a relatively large amount of lubricating oil into the transmission 20 for the purpose of preventing seizure of sliding portions. Since the pump drive shaft 53 is rotationally driven at a relatively high speed by the drive torque transmitted through the first torque transmission path, the discharge amount of the oil pump 51 becomes large, so that a sufficient amount of oil is supplied. Can be done.

As shown in FIG. 4, when the torque output from the engine 10 is stopped and the drive wheels 25 rotate on the coast, the second helical gear 83 is subjected to the axial load generated by the torque input to the second helical gear 83. The first clutch 71 is released while the clutch 75 of the above is connected. Therefore, a part of the rotational torque of the drive wheels 25 is transmitted to the pump drive shaft 53 via the second torque transmission path to drive the oil pump 51. In this case, the second gear ratio β when the rotation is transmitted from the second drive gear 113 to the second driven gear 57 is relatively small, for example, the rotation speed is reduced and transmitted.

When the vehicle travels on the coast without outputting torque from the engine 10, the risk of seizure of the sliding portion is small, so that the amount of lubricating oil to be supplied to the transmission 20 may be small. The pump drive shaft 53 is rotationally driven at a relatively low speed by the drive torque transmitted via the second torque transmission path, so that the required oil discharge amount is secured and the friction is reduced.

Therefore, the rotational torque of the drive wheels 25 consumed as the drive torque of the oil pump 51 during coastal travel is reduced, and the deceleration force of the vehicle can be reduced. Therefore, the torque output from the engine 10 can be reduced at the time of the next acceleration, and the fuel consumption can be improved. Further, the oil pump drive device 50 according to the present embodiment uses a clutch mechanism using a helical gear to reduce the drive torque of the oil pump 51 during coast travel as compared with drive travel, regardless of electrical control. Can be done. Therefore, the driving torque of the oil pump 51 is adjusted by a mechanical action according to the operating state of the engine 10 or the running state of the vehicle without increasing the load on the control device of the vehicle.

Further, when the oil pump drive device 50 is applied to a hybrid vehicle provided with a drive motor other than the engine 10 as a vehicle drive source, the torque output from the drive motor at the time of the next acceleration can be reduced. The power consumption efficiency can be improved. Further, when the hybrid vehicle is provided with a generator (power generation motor) that regenerates power using the rotational torque of the drive wheels 25, the rotational torque of the drive wheels 25 consumed as the drive torque of the oil pump 51 is reduced. Therefore, the regeneration efficiency can be improved. Further, by reducing the amount of oil discharged by the oil pump 51 during coastal traveling, it is possible to improve the utilization efficiency of the lubricating oil circulating in the transmission 20.

<1-4. Modification example>
The oil pump drive device 50 according to the present embodiment is not limited to the above example, and can be variously modified. Hereinafter, a modified example of the oil pump drive device according to the present embodiment will be described.

FIG. 5 is a schematic view showing an oil pump drive device 50A according to a modified example. The oil pump drive device 50A according to the modified example has a first one-way clutch 120 between the first driven gear 55 and the pump drive shaft 53, and is between the second driven gear 57 and the pump drive shaft 53. Has a second one-way clutch 125. The first one-way clutch 120 has, for example, a first rotating member fixed to the first driven gear 55 side and a second rotating member fixed to the pump drive shaft 53 side, and has one rotation direction. Allows relative rotation to, while prohibiting relative rotation in other directions of rotation. The first one-way clutch 120 allows the relative rotation of the first driven gear 55 in one rotational direction with respect to the pump drive shaft 53, while the relative rotation of the first driven gear 55 in the other rotational direction. Rotation is prohibited.

Similarly, the second one-way clutch 125 has, for example, a first rotating member fixed to the second driven gear 57 side and a second rotating member fixed to the pump drive shaft 53 side. Allows relative rotation in the direction of rotation while prohibiting relative rotation in other directions of rotation. The second one-way clutch 125 allows the relative rotation of the second driven gear 57 in one rotation direction with respect to the pump drive shaft 53, while the relative rotation of the second driven gear 57 in the other rotation direction. Rotation is prohibited. Known one-way clutches can be used as the first one-way clutch 120 and the second one-way clutch 125.

Specifically, the first one-way clutch 120 and the second one-way clutch 125 are configured as follows. The first one-way clutch 120 is configured to engage when the torque output from the engine 10 is transmitted to the first driven gear 55 via the first torque transmission path during driving of the vehicle. Will be done. As a result, the pump drive shaft 53 rotates together with the first driven gear 55 when the vehicle is being driven. Further, the first one-way clutch 120 does not engage with the rotation of the pump drive shaft 53, which is rotated by the drive torque transmitted via the second torque transmission path, when the vehicle is traveling on the coast. The 53 and the first driven gear 55 are configured to rotate relative to each other. As a result, the rotational torque transmitted from the pump drive shaft 53 to the first driven gear 55 is reduced when the vehicle is traveling on the coast.

On the other hand, the second one-way clutch 125 is engaged when the rotational torque of the drive wheels 25 is transmitted to the second driven gear 57 via the second torque transmission path when the vehicle is traveling on the coast. It is composed. As a result, the pump drive shaft 53 rotates together with the second driven gear 57 when the vehicle is traveling on the coast. Further, the second one-way clutch 125 does not engage with the rotation of the pump drive shaft 53, which is rotated by the drive torque transmitted via the first torque transmission path, when the vehicle is driven. The 53 and the second driven gear 57 are configured to rotate relative to each other. As a result, the rotational torque transmitted from the pump drive shaft 53 to the second driven gear 57 is reduced when the vehicle is being driven.

That is, when the vehicle is driving, the rotational torque transmitted to the second clutch output shaft 111, the second drive gear 113, and the second driven gear 57 that form the second torque transmission path is significantly reduced. Or become zero. Further, when the vehicle is traveling on the coast, the rotational torque transmitted to the first clutch output shaft 91, the first drive gear 93, and the first driven gear 55 constituting the first torque transmission path is significantly reduced. Or become zero. Therefore, the rotation of the drive gear and the driven gear on the torque transmission path other than the torque transmission path for transmitting the drive torque to the oil pump 51 is suppressed in both the driving state and the coast running, and the gears are stirred. Loss is reduced. As a result, the torque loss due to the oil pump drive device 50 can be further reduced.

In the oil pump drive device 50A according to the modified example, either the first one-way clutch 120 or the second one-way clutch 125 may be omitted. In this case, the agitation loss of the gear can be reduced and the torque loss can be reduced during either the driving running or the coast running of the vehicle.

<< 2. Second Embodiment >>
Next, the oil pump drive device 150 according to the second embodiment of the present invention will be described. FIG. 6 is a schematic view showing the oil pump drive device 150 according to the present embodiment. In the oil pump drive device 150 according to the present embodiment, the first torque transmission path is configured in the same manner as the oil pump drive device 50 according to the first embodiment, while the configuration of the second torque transmission path is the second. The configuration of the second torque transmission path of the oil pump drive device 50 according to the first embodiment is different. Hereinafter, the oil pump drive device 150 according to the present embodiment will be described focusing on the differences from the oil pump drive device 50 according to the first embodiment.

<2-1. Configuration example of oil pump drive device>
In the oil pump drive device 150 according to the present embodiment, the one-way clutch 155 is used instead of the clutch (second clutch 75) that switches the transmission or disconnection of torque by the axial load generated by the torque input to the second helical gear 83. Is used to switch torque transmission or interruption through the second torque transmission path. Specifically, the clutch input shaft 151 provided with the second helical gear 83 has a first clutch 71 on the first drive gear 93 side (one end side). Therefore, the first torque transmission path is composed of the clutch input shaft 151, the first clutch 71, the first clutch output shaft 91, the first drive gear 93, the first driven gear 55, and the pump drive shaft 53. There is.

On the other hand, the clutch input shaft 151 does not have a clutch (second clutch) on the second drive gear 113 side (the other end side). On the other end side of the clutch input shaft 151, a second drive gear 113 that rotates integrally with the clutch input shaft 151 is provided. Therefore, when the output shaft 11 of the engine 10 or the input shaft 21 of the transmission 20 rotates and the second helical gear 83 rotates, the second drive gear 113 always rotates and the second drive gear 113 rotates. The second driven gear 57 that meshes with the gear rotates. A one-way clutch 155 is provided between the second driven gear 57 and the pump drive shaft 53. As the one-way clutch 155, a known one-way clutch can be used.

The one-way clutch 155 is configured to engage when the rotational torque of the drive wheels 25 is transmitted to the pump drive shaft 53 via the second torque transmission path during coasting of the vehicle. As a result, the pump drive shaft 53 rotates together with the second driven gear 57 when the vehicle is traveling on the coast. Further, the one-way clutch 155 is not engaged with the pump drive shaft 53 by the rotation of the pump drive shaft 53 which is rotated by the drive torque transmitted through the first torque transmission path during the drive traveling of the vehicle, and the one-way clutch 155 is the third with the pump drive shaft 53. The driven gear 57 of 2 is configured to rotate relative to each other. A second torque transmission path is composed of a clutch input shaft 151, a second drive gear 113, a second driven gear 57, a one-way clutch 155, and a pump drive shaft 53.

<2-2. Action of oil pump drive>
In the oil pump drive device 50 according to the present embodiment, the first clutch 71 is generated by the axial load generated by the torque input to the second helical gear 83 during the drive running in which the drive wheels 25 are rotated by the torque output from the engine 10. Is connected. Therefore, a part of the torque output from the engine 10 is transmitted to the pump drive shaft 53 as the drive torque of the oil pump 51 via the first torque transmission path to drive the oil pump 51. In this case, the first gear ratio α when the rotation is transmitted from the first drive gear 93 to the first driven gear 55 is relatively large, for example, the rotation speed is increased and transmitted.

At this time, the second drive gear 113 and the second driven gear 57 also rotate with the rotation of the clutch input shaft 151. In this case, the second gear ratio β when the rotation is transmitted from the second drive gear 113 to the second driven gear 57 is relatively small, for example, the rotation speed is reduced and transmitted. Therefore, when the vehicle is driving, the rotation speed of the second driven gear 57 becomes smaller than the rotation speed of the pump drive shaft 53, and the one-way clutch 155 causes the second driven gear 57 and the pump drive shaft 53 to be engaged with each other. Due to the relative rotation, torque transmission is cut off.

When the torque output from the engine 10 is stopped and the drive wheels 25 rotate on the coast, the first clutch 71 is released by the axial load generated by the torque input to the second helical gear 83. Therefore, the transmission of torque by the first clutch 71 is cut off. Further, while the second drive gear 113 and the second driven gear 57 rotate with the rotation of the clutch input shaft 151, torque is not transmitted to the pump drive shaft 53 via the first torque transmission path, so that one way The clutch 155 is engaged.

As a result, a part of the rotational torque of the drive wheels 25 is transmitted to the pump drive shaft 53 via the second torque transmission path to drive the oil pump 51. In this case, the second gear ratio β when the rotation is transmitted from the second drive gear 113 to the second driven gear 57 is relatively small, for example, the rotation speed is reduced and transmitted. Therefore, the pump drive shaft 53 is rotationally driven at a relatively low speed by the drive torque transmitted through the second torque transmission path, so that the required oil discharge amount is secured and the friction is reduced.

As described above, according to the oil pump drive device 150 according to the present embodiment, the same effect as that of the oil pump drive device 50 according to the first embodiment can be obtained, and the clutch (second clutch) can be obtained. By omitting the above, the torque loss due to the dragging of the clutch can be reduced. Further, according to the oil pump drive device 150 according to the present embodiment, the weight and the manufacturing cost can be reduced by omitting the clutch.

Although the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited to such examples. It is clear that a person having ordinary knowledge in the field of technology to which the present invention belongs can come up with various modifications or modifications within the scope of the technical ideas described in the claims. , These are also naturally understood to belong to the technical scope of the present invention.

For example, in the above embodiment, the ratio of the number of teeth R2 of the first driven gear 55 to the number of teeth R1 of the first drive gear 93 and the number of teeth R3 of the second drive gear 113 of the second driven gear 57 By making the ratio of the number of teeth R4 different, the driving torque of the oil pump 51 during the coast running of the vehicle is reduced as compared with the driving running, but the present invention is not limited to this example. The oil pump 51 is driven by providing an intermediate gear between the first drive gear 93 and the first driven gear 55, or at least one of the second drive gear 113 and the second driven gear 57. The torque may be different. An oil pump drive device having such a configuration can also obtain the same effect as the oil pump drive device according to each of the above embodiments.

Further, in the modification of the first embodiment and the second embodiment described above, between the first driven gear 55 and the pump drive shaft 53, or between the second driven gear 57 and the pump drive shaft 53. Although a one-way clutch is provided between the two, the present invention is not limited to such an example. For example, the one-way clutch may be interposed in the middle of the pump drive shaft 53. An oil pump drive device having such a configuration can also obtain the same effect as the oil pump drive device according to each of the above embodiments.

50 Oil pump drive device 51 Oil pump 53 Pump drive shaft 55 1st driven gear 57 2nd driven gear 61 1st helical gear 63 3rd helical gear 71 1st clutch 75 2nd clutch 81 Clutch input shaft 83 2 helical gear 91 1st clutch output shaft 93 1st drive gear 111 2nd clutch output shaft 113 2nd drive gear 120 1st one-way clutch 125 2nd one-way clutch 155 one-way clutch

Claims (8)

In a vehicle oil pump drive equipped with an oil pump that is driven by the rotation of the output shaft of the engine.
A first torque transmission mechanism that connects the output shaft of the engine and the drive shaft of the oil pump at the first gear ratio, and
A second torque transmission mechanism for connecting the output shaft of the engine and the drive shaft of the oil pump at a second gear ratio different from the first gear ratio is provided.
The first torque transmission mechanism has a first clutch.
The second torque transmission mechanism has a second clutch.
The first clutch and the second clutch are clutches for switching torque transmission or interruption according to an axial load generated by torque input to a common helical gear, which is a vehicle oil pump drive device. The vehicle oil pump drive device according to claim 1, wherein when one of the first clutch and the second clutch is in a torque transmission state, the other clutch is in a torque cutoff state. While the vehicle is running, the first clutch is in a torque transmission state when the engine outputs torque, while the second clutch is in a torque cutoff state, and when the engine does not output torque, the first clutch is in a torque transmission state. The vehicle oil pump drive device according to claim 2, wherein the clutch of No. 2 is in a torque transmission state while the first clutch is in a torque cutoff state. The vehicle oil pump drive device according to claim 3, wherein the first gear ratio is larger than the second gear ratio. When an axial load is generated in one direction by the torque input to the helical gear, the first clutch is engaged while the second clutch is disengaged, and the torque input to the helical gear causes the other direction. The vehicle oil pump drive device according to any one of claims 1 to 4 , wherein the first clutch is disengaged while the second clutch is connected when an axial load is generated. The vehicle according to any one of claims 1 to 5 , wherein the first torque transmission mechanism includes a first one-way clutch in a torque transmission path from the first clutch to the drive shaft of the oil pump. Oil pump drive. The vehicle according to any one of claims 1 to 6 , wherein the second torque transmission mechanism includes a second one-way clutch in a torque transmission path from the second clutch to the drive shaft of the oil pump. Oil pump drive. The helical gear is provided in a torque transmission path that transmits torque from the output shaft of the engine to the rotation shaft on the drive wheel side.
While the vehicle is running, torque is input to the helical gear so that an axial load in one direction is generated when the engine outputs torque, and when the engine does not output torque, the other The vehicle oil pump drive device according to claim 5 , wherein torque is input to the helical gear so that an axial load is generated in the direction.

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