JPH11117995A - Gear box supporting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress induction of the coupled vibration of an output shaft being laterally vibrated so as to ensure comfortableness by providing a pair of side mounts for supporting both sides, orthogonal to the output shaft of a gearbox, respectively to the same height as the output shaft through elastic bodies. SOLUTION: When torque fluctuation is generated to the rotation of a motor 11 and dirigible road wheels, torsional torque is generated to an output shaft 15 of a gearbox 10 so as to vibrate both sides of the gearbox 10 in a rolling direction. This vibration (torque) is mainly supported by side mounts 12 positioned on both sides of the gearbox 10. Each side mount 12 is vertically expanded/contracted, but a plane (s) (a mount supporting face) including the output shaft 15 of the gearbox 10 vibrates in a rolling direction with the output shaft 15 as the center so as to suppress induction of coupled vibration of the output shaft 15 being laterally vibrated by fluctuating torque that oscillates both sides of the gearbox 10 vertically. As a result, vibration transmitted from the gearbox 10 to a vehicle body side is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a gear box support device.

[0002]

2. Description of the Related Art It is conceivable to configure a power transmission path as shown in FIG. 7 in a vehicle provided with an electric motor for generating a driving force for running the vehicle.

[0003] Reference numeral 1 denotes an axle of a driving wheel, and a differential 2 is interposed in an intermediate portion of the axle. An output shaft of a gear box 4 for reduction is connected to a drive pinion of the differential 2 via a propeller shaft 3.

[0004] The gear box 4 for reduction is mounted on the vehicle body side. The gear box 4 is provided with two input shafts, and an electric motor 5 is connected to each of them. 1
Gears that mesh with the same gear ratio are interposed between the two output shafts and the two input shafts.

When the electric motor 5 is supplied with power, it generates a driving force for running the vehicle. The driving force is output to the propeller shaft 3 via the gear box 4 for reduction, and transmitted from the differential 2 to the driving wheels 6 via the axle 1.

As a related prior art, a power unit including an electric motor is supported via a liquid-sealed mount bush having a variable spring constant (Japanese Patent Laid-Open No. 9-215104), and a differential of a power transmission path is omitted ( Japanese Unexamined Patent Publication No. Hei 9-215101), in which an auxiliary machine can be driven by an electric motor even while the vehicle is stopped (Japanese Unexamined Patent Publication No. Hei 5-14744).
No. 5), and the like.

[0007]

In a vehicle having a power transmission path as shown in FIG. 7, when a torque fluctuation occurs in the rotation of the electric motor 5, a torsional vibration occurs in the output shaft of the gear box 4. In addition, the driving wheels 6
When a torque fluctuation occurs in the rotation of the (tire), the axle 1
, The torsional vibration is input to the gear box 4. Therefore, the transmission of these vibrations to the vehicle body not only impairs the comfortable riding comfort of the vehicle, but also may cause damage to the gear box 4 and the like when a large fluctuation torque or the like is input.

An object of the present invention is to provide an effective countermeasure for solving such a problem.

[0009]

According to a first aspect of the present invention, in a vehicle provided with an electric motor for generating a driving force for running a vehicle and a gearbox for reducing the speed, both sides in a direction orthogonal to an output shaft of the gearbox are respectively provided. A pair of side mounts is provided at the same height as the output shaft and supported via an elastic body.

In a second aspect based on the first aspect, there is provided a center mount for supporting the output shaft of the gear box coaxially with an output shaft via an elastic body.

[0011]

According to the first aspect of the present invention, the weight of the gear box is supported at the same height on a plane including the output shaft by the pair of side mounts. When a torque fluctuation occurs in the rotation of the electric motor or the rotation of the drive wheels, a torsional torque is generated in the output shaft of the gear box, and both sides of the gear box vibrate vertically (in the roll direction). This vibration (torque) is supported by side mounts 12 located on both sides of the gear box.

Although each side mount expands and contracts up and down, a plane including the output shaft of the gear box swings in the roll direction about the output shaft. For this reason, induction of coupled vibration in which the output shaft swings left and right due to the fluctuation torque that swings up and down on both sides of the gear box is suppressed. Therefore, the vibration transmitted from the gear box to the vehicle body is suppressed to a low level via the side mount, and it is possible to secure a comfortable ride of the vehicle while preventing damage to the gear box and the like.

In the second invention, the center mount also receives a small amount of torque (vibration). However, since the center mount is rotatably supported on the same axis as the output shaft of the gear box, the output shaft induces coupled vibrations that swing right and left. Can be effectively suppressed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIGS. 1 to 5, reference numeral 10 denotes a reduction gear box, and a motor 11 is connected to two input shafts. The gearbox 10 has a side mount 12 that supports both sides in a direction (vehicle width direction) perpendicular to the output shaft 15 at the same height as the output shaft, and a center that supports the rear motor coaxially with the output shaft. It is mounted on the vehicle body via the mount 13.

The side mount 12 is a rubber block 16
Plates 17 and 18 (metal plates) are adhered to the upper and lower surfaces of the vehicle, and are connected to the vehicle body side by bolts and nuts via the lower plate 18. Brackets 19 are connected to both sides of the gear box 10 with bolts and nuts, respectively.
A mounting surface 20 having substantially the same height as the output shaft is formed on each bracket 19. The side mount 12 is connected to the mounting surface 20 via the upper plate 17 with bolts and nuts.

Both ends 21 of the lower plate 18 rise up and down before and after the rubber block 16, and the upper plate 1
A locking portion 22 that bends inward is formed at the tip that extends upward from 7. Rubber 23 is provided on the inner surface of both ends 21,
The rubber 24 is bonded to the inner surface of the. Rubber block 16
Is provided with a hole 25 (hole) for adjusting the spring characteristics.

The center mount 13 is an outer cylinder 26 (color)
Rubber bush 28 between the inner cylinder 27 (bearing metal)
It is attached to the vehicle body side with bolts and nuts via a bracket 29 that encloses the collar 26 together with a lower support at the center of the U-shape.

A pin 30 is attached to the inner cylinder 27 of the rubber bush 28.
The pin 30 is rotatably inserted, and the pin 30 is coaxially fixed to the output shaft 15 via a frustoconical stay 31 at the center of the rear surface of the gear box 10 (between the electric motors 11). Numeral 32 denotes a nut for preventing the pin 30 from coming off.
Of the pin 30 protruding from the inner cylinder 27 (male thread portion)
To join.

FIG. 6 shows the spring characteristics with respect to the vertical expansion and contraction (stroke) of the side mount 12. On the contraction side, the elastic force (supporting force) is small and gradually rises until the curl 25 of the rubber block 16 is crushed in accordance with the stroke. On the other hand, when the curl 25 is crushed, the elastic force suddenly increases from that point. become. On the extension side, the elastic force is small and rises gently at the corner 25 of the rubber block 16 according to the stroke, while the upper plate 17
Abuts against the rubber 24 of the locking portion 22, the rubber 24
, The elastic force of the entire side mount rises sharply.

With this configuration, the gear box 10
The weight of the motor 11 is supported at the same height at three points on a plane including the output shaft 15 of the gear box 10 via the side mount 12 and the center mount 13. When the electric motor 11 is driven, the driving force is transmitted to the gear box 10.
And transmitted to the drive wheels via the axle from the differential (see FIG. 7).

When a torque fluctuation occurs in the rotation of the electric motor 11 or the rotation of the driving wheels, a torsional torque is generated in the output shaft 15 of the gear box 10, and both sides of the gear box 10 vibrate in the roll direction. This vibration (torque) is mainly supported by side mounts 12 located on both sides of the gear box 10.

Each side mount 12 expands and contracts up and down, but a plane s (mount support surface) including the output shaft 15 of the gear box 10 swings about the output shaft 15 in the roll direction. Therefore, induction of coupled vibration in which the output shaft 15 swings left and right due to the fluctuation torque that swings up and down on both sides of the gear box 10 can be suppressed.

Although the center mount 13 also receives a slight torque (vibration), it is coaxial with the output shaft 15 of the gear box 10 (the mount support surface s accompanying the expansion and contraction of the side mount 12).
(The center of swing in the roll direction) is rotatably supported, so that coupled vibration in which the output shaft 15 swings left and right can be effectively suppressed.

Since the side mount 12 has the mount characteristics as shown in FIG. 6, when the fluctuation torque that swings both sides of the gear box 10 in the roll direction is small, it is softly supported and transmitted to the vehicle body by the elasticity of the rubber 16. Vibration is well absorbed. When the fluctuation torque increases, a large supporting force (elastic force) corresponding to the fluctuation torque is obtained, and the rubber 1
Vibration toward the vehicle body can be sufficiently absorbed by the elasticity of 6,24.

When the axle moves up and down, the gear box 10 swings back and forth by the axial force accompanying the swing of the propeller shaft (see FIG. 7). In the side mounts 12 on both sides, when the upper plate 17 is displaced back and forth, it strikes both ends 21 of the lower plate 18,
The swinging of the gear box 10 back and forth is also reduced.
In addition, the collision between the plates 17 and 18 is reduced by the rubbers 23 at both ends 21, and the generation of impact noise can be prevented.

As a result, the vibration transmitted from the gearbox 10 to the vehicle body is reduced, so that a comfortable ride of the vehicle can be secured while preventing the gearbox 10 and the like from being damaged. In the side mount 12,
By the simple and easy means of providing the lug 25 of the rubber block 16 and the locking portion 22 with the rubber 24,
Desirable non-linear spring characteristics as shown in FIG. 6 can be realized at low cost.

[Brief description of the drawings]

FIG. 1 is a front view of a partially cutaway showing an embodiment of the present invention.

FIG. 2 is a right side view of the same.

FIG. 3 is a plan view of the same.

FIG. 4 is an explanatory perspective view of the same.

FIG. 5 is an enlarged view of the same side mount.

FIG. 6 is a characteristic diagram of the side mount.

FIG. 7 is an explanatory diagram of a configuration of a power transmission path.

[Explanation of symbols]

 Reference Signs List 10 Gear box 11 Electric motor 12 Side mount 13 Center mount 15 Output shaft 16 Rubber block 17 Upper plate 18 Lower plate 19 Bracket 23, 24 Rubber 26 Outer cylinder 27 Inner cylinder 28 Rubber bush 29 Bracket 30 Pin

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yuji Kusara Nissan Diesel Kogyo Co., Ltd. (72) Inventor Toshihiko Abe Nissan Diesel Kogyo Inside the corporation

Claims (2)

[Claims] In a vehicle equipped with an electric motor for generating a driving force for running the vehicle and a gearbox for reducing the speed, both sides of the gearbox in a direction orthogonal to an output shaft are each provided with an elastic body at the same height as the output shaft. A gear box support device, comprising a pair of side mounts for supporting the gear box. 2. The support device according to claim 1, further comprising a center mount for supporting the output shaft of the gear box coaxially with the output shaft via an elastic body.