JP7376382B2 - drive device - Google Patents

Description

The present invention relates to a drive device.

BACKGROUND ART Conventionally, as a drive device that includes a prime mover and a transmission that receives power from the prime mover and outputs the power to a propulsion shaft of a vehicle, for example, the one described in Patent Document 1 is known. Patent Document 1 describes a power unit including an engine, a clutch device, and a transmission. The engine, clutch device, and transmission are arranged in parallel with each other in the vehicle width direction. The propulsion shaft of the vehicle is attached to the output shaft of the transmission, and extends to the side of the transmission so as to extend toward the engine.

Japanese Patent Application Publication No. 2004-203296

In the case of the above-mentioned conventional technology, when attempting to install a braking device on the drive device to brake the output shaft of the transmission, the braking device is attached to the propulsion shaft that is arranged to pass near the transmission and the engine (prime mover). It is possible that However, depending on the radial dimension of the braking device, there is a possibility that the braking device may interfere with the transmission or the engine (prime mover). If the distance between the transmission or the engine (prime mover) and the braking device is increased to avoid interference, the drive device will become larger.

An object of the present invention is to provide a drive device that can be provided with a braking device that brakes the output shaft of a transmission while suppressing the increase in size of the drive device.

A drive device according to one aspect of the present invention is a drive device mounted on a vehicle, and includes a prime mover, a transmission that receives power from the prime mover and outputs the power to a propulsion shaft of the vehicle, and a transmission that is arranged in the axial direction of the prime mover. a braking device that brakes the output shaft of the parallel transmission; the distance between the output shaft and the prime mover in the radial direction of the output shaft is smaller than the radial dimension of the braking device; A first output section that outputs power to the prime mover side and a second output section that outputs power to the side of the output shaft opposite to the prime mover are integrally and directly connected to each other so as to be rotatable, and the propulsion shaft is One output is attached to the braking device, and a braking device is attached to the second output.

In the drive device according to one aspect of the present invention, the braking device is attached to the second output portion, and the first output portion and the second output portion are directly connected to each other so as to be integrally rotatable. By braking the output shaft of the transmission by the braking device, it is possible to brake the propulsion shaft attached to the first output section. In addition, since the braking device is attached to the second output part, even if the braking device has a radial dimension larger than the distance from the output shaft to the prime mover in the radial direction of the output shaft, the distance will not increase. No longer needed. Therefore, in this drive device, it is possible to provide a braking device that brakes the output shaft of the transmission while suppressing the increase in size of the drive device.

In one embodiment, the propulsion shaft is a propeller shaft having a bendable joint, and the propeller shaft may be attached to the first output part such that the joint is adjacent to the prime mover. In this case, the space adjacent to the prime mover can be used, for example, to optimize the degree of bending of the joint.

In one embodiment, the prime mover is a motor generator, and the drive device may be mounted behind the rearmost shaft of the vehicle so that the motor generator is sandwiched between the rearmost shaft and the transmission. In this case, since the transmission is arranged behind the motor generator in the vehicle, the motor generator can be easily arranged closer to the center of the vehicle, for example, even if the motor generator is a high voltage component.

According to the present invention, it is possible to provide the drive device with a braking device that brakes the output shaft of the transmission while suppressing the increase in size of the drive device.

FIG. 1 is a block diagram showing a functional configuration of a vehicle including a drive device according to an embodiment. FIG. 3 is a longitudinal cross-sectional view of the drive device. It is a block diagram showing the functional composition of a vehicle provided with a drive device of a modification.

Embodiments of the present invention will be described below with reference to the drawings. In the following description, the same or equivalent elements will be denoted by the same reference numerals, and overlapping description will be omitted.

FIG. 1 is a block diagram showing the functional configuration of a vehicle V according to an embodiment. A vehicle V shown in FIG. 1 is equipped with a drive device 10 that includes a motor generator (prime mover) 2, a transmission 4, and a braking device 6. Vehicle V is an electric vehicle that runs using the driving force of motor generator 2, and is, for example, a bus. A direction Fr in FIG. 1 indicates the front direction of the vehicle V. The drive device 10 is mounted behind the rearmost shaft RX of the vehicle V so that the motor generator 2 is sandwiched between the rearmost shaft RX and the transmission 4.

The motor generator 2 is a motor generator that functions as both an electric motor and a generator. When the vehicle V is running, the motor generator 2 generates driving force for running using electric power supplied from a battery (not shown) through an inverter (not shown). When the vehicle V is decelerating, the motor generator 2 generates regenerative torque and generates regenerative power. Regenerative power generated by the motor generator 2 is supplied to the battery via the inverter.

The transmission 4 is, for example, a manual transmission for an electric vehicle, and receives power from the motor generator 2 and outputs the power to a propeller shaft (propulsion shaft) 12 of the vehicle V. An input shaft 21 (see FIG. 2) of the transmission 4 is connected to an output shaft of the motor generator 2. An output shaft (output shaft) 31 of the transmission 4 is connected to the propeller shaft 12. The transmission 4 is connected to left and right drive wheels 18 via a propeller shaft 12, a differential gear 14, and a drive shaft 16. Transmission 4 transmits the driving force generated by motor generator 2 to drive wheels 18 of vehicle V.

FIG. 2 is a longitudinal sectional view of the drive device 10. As shown in FIG. 2, the transmission 4 includes an input shaft 21, a fixed gear 23, a fixed gear 25, an output shaft 31, an idling gear 33, an idling gear 35, and a shift mechanism 37. The input shaft 21, fixed gear 23, fixed gear 25, output shaft 31, idling gear 33, idling gear 35, and shift mechanism 37 are housed in a transmission case 28.

Input shaft 21 is rotatably supported within transmission case 28 by a pair of bearings 27 . The input shaft 21 is connected to an output shaft of a motor generator 2 that is a power source of the vehicle V, and rotates in response to the driving force generated by the motor generator 2.

For example, a fixed gear 23 and a fixed gear 25 having different numbers of teeth are fixed to the input shaft 21. The fixed gear 23 and the fixed gear 25 are fixed to the input shaft 21 so as to be rotatable together with the input shaft 21, and rotate together with the input shaft 21 in response to the driving force from the motor generator 2.

The output shaft 31 is rotatably supported within the transmission case 28 by a pair of bearings 39 . The output shaft 31 is provided apart from the input shaft 21 and is arranged parallel to the input shaft 21. That is, the axial direction of the output shaft 31 is parallel to the axial direction of the motor generator 2.

For example, the output shaft 31 extends parallel to the axial direction of the motor generator 2 (the axial direction of the input shaft 21) so as to penetrate the transmission case 28. The length of output shaft 31 is longer than the length of transmission case 28 in the axial direction of motor generator 2 . The output shaft 31 receives the rotational force of the input shaft 21 and transmits the rotational force to the propeller shaft 12 and the braking device 6.

One end 31a of the output shaft 31 protrudes from one end wall 28a of the transmission case 28. One end portion 31a is the end portion of the output shaft 31 on the motor generator 2 side. One end wall portion 28a is a wall portion of transmission case 28 on the motor generator 2 side. One end portion 31a functions as a first output portion that outputs power to the motor generator 2 side of the output shaft 31.

One end wall portion 28a includes a mounting portion 28c to which motor generator 2 is mounted. One end wall portion 28a extends, for example, along a virtual plane orthogonal to the axial direction of motor generator 2 (the axial direction of input shaft 21).

The propeller shaft 12 is attached to one end 31a of the output shaft 31. The propeller shaft 12 has a bendable joint 12a. The propeller shaft 12 is attached to one end 31a of the output shaft 31 so that the joint 12a is adjacent to the motor generator 2. "The joint 12a is adjacent to the motor generator 2" means that in the axial direction of the output shaft 31, the distance from the one end wall 28a to the joint 12a is the same as the distance from the one end wall 28a (attachment part 28c) to the motor generator 2. means smaller than.

In this case, the distance from joint 12a to differential gear 14 can be made longer than when joint 12a is not adjacent to motor generator 2. "The joint 12a is not adjacent to the motor generator 2" means that in the axial direction of the output shaft 31, the distance from the one end wall 28a to the joint 12a is the same as the distance from the one end wall 28a (attachment part 28c) to the motor generator 2. means greater than the distance. As the distance from the joint 12a to the differential device 14 increases, for example, even if the propeller shaft 12 from the joint 12a to the differential device 14 is inclined with respect to the axial direction of the output shaft 31, the angle of inclination will be reduced. Since the angle becomes smaller, it becomes easier to reduce the degree of bending of the joint 12a. Therefore, the degree of bending of the joint 12a can be optimized.

The other end 31b of the output shaft 31 protrudes from the other end wall 28b of the transmission case 28. The other end 31b is the end of the output shaft 31 on the opposite side of the motor generator 2. The other end wall portion 28b is a wall portion of the transmission case 28 on the side opposite to the motor generator 2. The other end portion 31b functions as a second output portion that outputs power to the side of the output shaft 31 opposite to the motor generator 2. A braking device 6 is attached to the other end 31b of the output shaft 31.

The other end wall portion 28b includes a support portion 28d that supports the end of the input shaft 21 on the opposite side from the motor generator 2. The other end wall portion 28b extends, for example, along a virtual plane orthogonal to the axial direction of the motor generator 2 (the axial direction of the input shaft 21). The other end wall 28b is substantially parallel to the one end wall 28a.

The support portion 28d may protrude on the opposite side from the motor generator 2 at the other end wall portion 28b. The protruding height of the support portion 28d may be set within a range such that the support portion 28d does not interfere with the braking device 6 attached to the other end portion 31b of the output shaft 31, for example. Here, the protrusion height of the support portion 28d is set to a protrusion height such that the support portion 28d does not interfere with the wire attachment portion 6c of the braking device 6 closest to the motor generator 2, for example.

In the radial direction of the output shaft 31, the separation distance L from the output shaft 31 to the motor generator 2 is smaller than the radial dimension D1 of the braking device 6. The separation distance L is, for example, the separation distance from the axis of the output shaft 31 to a position in the motor generator 2 closest to the output shaft 31 side. The dimension D1 is, for example, the radius of the brake drum 6a of the braking device 6.

In the radial direction of the output shaft 31, the separation distance D2 from the output shaft 31 to the support portion 28d is larger than the radial dimension D1 of the braking device 6. The separation distance D2 is, for example, the separation distance from the axis of the output shaft 31 to the position closest to the output shaft 31 in the support portion 28d.

The output shaft 31 has one end 31a and the other end 31b directly connected to each other so as to be integrally rotatable. The output shaft 31 may be configured as a single component, or may be configured to be integrally rotatable as two or more components.

The output shaft 31 is provided with an idling gear 33 and an idling gear 35 (a plurality of idling gears) having mutually different numbers of teeth. The idle gear 33 and the idle gear 35 are rotatably supported with respect to the output shaft 31 via a needle bearing 40 provided coaxially with the output shaft 31. Therefore, the idling gear 33 and the idling gear 35 are provided to be able to freely rotate (idle) with respect to the output shaft 31 while being meshed with the fixed gear 23 and the fixed gear 25, respectively.

The shift mechanism 37 is provided between the idle gear 33 and the idle gear 35 of the output shaft 31. The shift mechanism 37 is configured to be able to switch the connection state between the output shaft 31 and the idle gears 33 and 35. The connected state here includes a state where the input shaft 21 and the output shaft 31 are connected via the fixed gear 23 and the idling gear 33, and a state where the input shaft 21 and the output shaft 31 are connected via the fixed gear 25 and the idling gear. 35, and a state in which the output shaft 31 and the idle gears 33, 35 are disconnected and no power is transmitted between the input shaft 21 and the output shaft 31 (neutral state). and are included. The shift mechanism 37 switches these connection states in accordance with the operation of the shift lever of the vehicle V.

The braking device 6 brakes the output shaft 31 of the transmission 4. The braking device 6 here is a so-called center brake device, and functions as a parking brake device. The braking device 6 includes a brake drum 6a fixed to the other end 31b of the output shaft 31, and a brake shoe 6b pressed against the inner peripheral surface of the brake drum 6a. The braking device 6 is, for example, a mechanical type that uses a brake wire (not shown) to switch between activation and deactivation of the braking device 6, and has a wire attachment portion 6c to which the brake wire is attached. The wire attachment portion 6c expands the brake shoe 6b by being pulled by, for example, a brake wire. In addition, since the brake drum 6a only needs to rotate integrally with the output shaft 31, it may be fixed directly to the output shaft 31, or may be fixed indirectly via another member.

[Effect]
In the drive device 10 described above, the braking device 6 is attached to the other end 31b (second output portion) of the output shaft 31, and is attached to the one end 31a (first output portion) and the other end of the output shaft 31. 31b are directly connected to each other so as to be integrally rotatable. By braking the output shaft 31 of the transmission 4 by the braking device 6, it is possible to brake the propeller shaft 12 attached to the one end portion 31a. Further, since the braking device 6 is attached to the other end portion 31b, the braking device 6 has a radial dimension D1 larger than the separation distance L from the output shaft 31 to the motor generator 2 in the radial direction of the output shaft 31. Also, there is no need to increase the separation distance L. Therefore, in this drive device 10, it is possible to provide the brake device 6 that brakes the output shaft 31 of the transmission 4 while suppressing the increase in size of the drive device 10.

In the drive device 10, the propeller shaft 12 has a bendable joint 12a, and the propeller shaft 12 is attached to one end 31a of the output shaft 31 so that the joint 12a is adjacent to the motor generator 2. Thereby, the space adjacent to the motor generator 2 can be used, for example, in order to optimize the degree of bending of the joint 12a.

In the drive device 10, a motor generator 2 is used as a prime mover, and the drive device 10 is mounted behind the rearmost shaft RX of the vehicle V so that the motor generator 2 is sandwiched between the rearmost shaft RX and the transmission 4. . Here, for example, if the motor generator 2 is a so-called high voltage component, there may be restrictions on the mounting position of the motor generator 2 in the vehicle V. High-voltage components refer to electrical components for driving electric vehicles and hybrid vehicles, and refer to components for which prevention of electric shock during work is stipulated by law. For example, there may be a restriction such that the mounting position of the motor generator must be a predetermined distance or more inward from the outer surface of the vehicle V (towards the center of the vehicle V). In this case, in case of a drive system in which the motor generator is located at the rear end of the vehicle, the entire drive system must be placed at the front in order to meet the constraint requirements, and extra space is required at the rear of the vehicle for the motor generator. may remain. Therefore, according to the drive device 10, the transmission 4 is arranged behind the motor generator 2 in the vehicle. This makes it easier to place. As a result, it is possible to prevent excess space from remaining behind the motor generator 2 in the vehicle, and it is possible to improve space efficiency in the vehicle V.

[Modified example]
Although the embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above. The present invention can be implemented in various forms including the embodiments described above, with various changes and improvements based on the knowledge of those skilled in the art.

In the above embodiment, the drive device 10 is mounted behind the rearmost shaft RX of the vehicle V so that the motor generator 2 is sandwiched between the rearmost shaft RX and the transmission 4, but the present invention is not limited thereto. For example, as shown in FIG. 3, the driving device 10A may be mounted in front of the rearmost shaft RX of the vehicle V so that the motor generator 2 is sandwiched between the rearmost shaft RX of the vehicle V and the transmission 4. good.

In the embodiment described above, the output shaft 31 penetrates the transmission case 28, but the invention is not limited thereto. One end 31a of output shaft 31 does not need to protrude from one end wall 28a of transmission case 28. For example, even if a female thread is formed coaxially with the output shaft 31 at one end 31a and the propeller shaft 12 is attached using the female thread, the one end 31a is connected to the motor generator 2 side of the output shaft 31 to provide power. It can function as a first output section that outputs. The other end 31b of the output shaft 31 does not need to protrude from the other end wall 28b of the transmission case 28. For example, even if a female thread is formed coaxially with the output shaft 31 at the other end 31b and the braking device 6 is attached using the female thread, the other end 31b is connected to the motor generator 2 on the output shaft 31. can function as a second output section that outputs power to the opposite side.

In the above embodiment, the dimension D1 is the radius of the brake drum 6a of the braking device 6, but it also includes the dimensions of the components of the braking device 6 other than the brake drum 6a, such as the wire attachment portion 6c along the radial direction of the braking device 6. , may be included in the dimension D1.

In the embodiment described above, the distance D2 from the output shaft 31 to the support portion 28d in the radial direction of the output shaft 31 was larger than the radial dimension D1 of the braking device 6, but the present invention is not limited thereto. As long as the support portion 28d does not interfere with the braking device 6 attached to the other end 31b of the output shaft 31, the separation distance D2 may be smaller than the dimension D1.

In the embodiment described above, the protrusion height of the support portion 28d is such that the support portion 28d and the braking device 6 do not overlap in the axial direction of the motor generator 2 (the axial direction of the input shaft 21). It is not limited to this. As long as the separation distance D2 from the output shaft 31 to the support portion 28d is larger than the radial dimension D1 of the braking device 6, the protrusion height of the support portion 28d is greater than the distance between the support portion 28d and the brake device in the axial direction of the motor generator 2. The protruding height may overlap with 6.

In the embodiment described above, the joint 12a is attached to the one end portion 31a so as to be adjacent to the motor generator 2, but the present invention is not limited thereto. For example, the joint 12a may be adjacent to a part of the transmission case 28, or may not be adjacent to either the motor generator 2 or the transmission case 28.

In the above embodiment, the braking device 6 is a mechanical type using a brake wire, but for example, it may be an electric parking brake operated by electric control based on the operation of a button arranged in the cabin of the vehicle V. You can.

In the above embodiment, the braking device 6 was used as a parking brake, but the use is not limited to this. For example, the braking device 6 may be used as a so-called counter braking device for synchronizing the rotations of the input shaft 21 and the output shaft 31 according to the gear ratio when the transmission 4 changes gears.

In the above embodiment, the motor generator 2 is used as the prime mover in the drive device 10, but in addition to or in place of the motor generator 2, an internal combustion engine such as a diesel engine or a gasoline engine may be used as the prime mover.

In the above embodiment, a bus is exemplified as the vehicle V, but the vehicle V is not limited to this, and may be a large vehicle such as a truck, or a small or medium-sized vehicle such as a passenger car.

2... Motor generator (prime mover), 4... Transmission, 6... Braking device, 10, 10A... Drive device, 12... Propeller shaft (propulsion shaft), 12a... Joint, 31... Output shaft (output shaft), 31a... One end part (first output part), 31b...other end part (second output part), D1...dimension, D2, L...separation distance, RX...rearth axis, V...vehicle.

Claims (3)

A drive device mounted on a vehicle,
comprising a prime mover, a transmission that receives power from the prime mover and outputs the power to a propulsion shaft of the vehicle, and a braking device that brakes an output shaft of the transmission parallel to the axial direction of the prime mover,
In the radial direction of the output shaft, a separation distance from the output shaft to the prime mover is smaller than a dimension of the braking device in the radial direction,
The output shaft is capable of integrally rotating a first output portion of the output shaft that outputs power to a side of the prime mover, and a second output portion of the output shaft that outputs power to a side of the output shaft opposite to the prime mover. are directly connected to each other,
the propulsion shaft is attached to the first output section,
The braking device is a drive device attached to the second output section. The propulsion shaft is a propeller shaft having a bendable joint,
The drive device according to claim 1, wherein the propeller shaft is attached to the first output section so that the joint is adjacent to the prime mover. The prime mover is a motor generator,
The drive device according to claim 1 or 2, wherein the drive device is mounted behind the rearmost shaft of the vehicle so that the motor generator is sandwiched between the rearmost shaft of the vehicle and the transmission.

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