JP7323471B2 - Soundproof structure for power transmission device for vehicle - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular power transmission device, and more particularly to a soundproof structure in which a soundproof cover is attached to a case of the vehicular power transmission device.

A soundproof structure for a power transmission device for a vehicle, in which a soundproof cover having a sound absorbing material provided on the inner surface of a support plate is attached to the outside of a case of the power transmission device for a vehicle in such a manner that the sound absorbing material faces the case. Are known. The device described in Patent Literature 1 is one example, and a sound insulating cover 11 in which a sound absorbing material 12 is attached to a plate main body portion 11A or the like corresponds to a sound insulating cover. 12 is reflected by the plate main body 11A and the like, thereby suppressing the noise from diffusing to the outside (see paragraph 0016 and the like).

JP 2017-20475 A Japanese Patent Application Laid-Open No. 2009-109003

By the way, various exterior parts such as an actuator of an SBW (shift-by-wire) device are arranged outside the case of a vehicle power transmission device (see, for example, Patent Document 2). is generated, the problem is how to arrange the soundproof cover. Moreover, if there is a space between the case and the external component, noise may resonate in the space and become worse (amplified).

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a soundproof cover when exterior parts are arranged outside the case of a power transmission device for a vehicle with a space therebetween. To enable appropriate soundproofing by using

In order to achieve such an object, the present invention provides a soundproof cover provided with a sound absorbing material on the inner surface of a support plate, and is attached to the outside of a case of a power transmission device for a vehicle in such a manner that the sound absorbing material faces the case. (a) an exterior component is disposed outside the case with a space therebetween, and at least a portion of the soundproof cover is disposed in the space; (b) a sound insulating material is provided on the outer surface of the support plate of the soundproof cover so as to be in contact with the rear surface of the exterior component.

In such a soundproof structure for a power transmission device for a vehicle, at least part of the soundproof cover is arranged in the space between the case and the exterior part, and the outer surface of the support plate of the soundproof cover is provided with the exterior. Since the sound insulating material is provided so as to be in contact with the back surface of the component, the noise emitted from the case is absorbed and reduced by the sound absorbing material provided on the inner surface of the support plate, while the support plate and the exterior component are separated. Since the sound insulating material is present between them, deterioration of noise due to resonance is suppressed, and diffusion of noise can be appropriately prevented regardless of the presence of exterior parts. In addition, since at least a part of the soundproof cover is arranged in the space between the case of the vehicle power transmission device and the exterior component, the soundproof cover is provided so as to cover the exterior component, for example. It is compact and advantageous in terms of space.

1 is a schematic front view of an electric drive unit having a soundproof structure according to one embodiment of the present invention, viewed from the front side of a vehicle; FIG. FIG. 2 is a cross-sectional view of the II-II arrow portion in FIG. 1, that is, the portion where the exterior component and the soundproof cover are arranged; FIG. 3 is a perspective view of the soundproof cover of FIG. 2 as seen from the vehicle front side, which is the exterior component side; FIG. 3 is a perspective view of the soundproof cover of FIG. 2 as seen from the rear side of the vehicle, which is the side of the electric drive unit;

The present invention is applicable to various vehicles such as an engine-driven vehicle having an engine (internal combustion engine) as a driving force source, a hybrid vehicle having an engine and an electric motor as a driving force source, and an electric vehicle having only an electric motor as a driving force source. applied to the power transmission system of A vehicle power transmission device is, for example, a transaxle equipped with a differential device for distributing a driving force transmitted from a driving force source to left and right driving wheels. Also good. A drive unit in which a driving force source such as an electric motor is housed in a common case with the power transmission device may be used.

The case of the vehicular power transmission device can be composed of a single member, but can also be composed of a plurality of case members as necessary. Exterior parts attached to the outside of the case of a power transmission device for a vehicle include, for example, an actuator of an SBW (shift-by-wire) device that electrically switches the power transmission state of a power transmission mechanism in accordance with the operation of an operation member such as a shift lever, and the actuator thereof. electronic control equipment, electronic control equipment such as the PCU (Power Control Unit) that electrically controls the output of the driving force source for running, or various vehicle-mounted parts such as the valve body of the hydraulic control circuit. Become. This exterior component is arranged, for example, in the vehicle front portion of the case, but may also be arranged in the upper portion or the left and right side portions of the case, taking into consideration the configuration of the vehicle power transmission device and interference with peripheral components. determined as appropriate. INDUSTRIAL APPLICABILITY The present invention is preferably applied when an exterior component is arranged in a portion where noise such as gear noise is generated.

The support plate is suitably made of synthetic resin, but a support plate made of other materials such as metal can also be used. It is desirable that the sound insulating material provided on the outer surface of the support plate is provided so that the tip surface thereof contacts the back surface of the exterior part over substantially the entire surface, and the gap between the sound insulating material and the exterior part is filled with the sound insulating material. It is sufficient that at least a portion thereof is provided so as to be in contact with the rear surface of the exterior component. A block-shaped sound insulating material is preferably used as the sound insulating material so as to fill the gap with the exterior parts, but an annular sound insulating material may be provided so as to surround the gap. A sound absorbing material is provided on the inner surface of the support plate, and if necessary, a second sound insulating material may be provided so as to surround the sound absorbing material. It is desirable that the second sound insulating material also be provided so as to be in contact with the case of the vehicle power transmission device over substantially the entire circumference. The sound absorbing material is a porous material or a perforated plate structure that absorbs sound energy, and urethane foam, glass wool, nonwoven fabric, or the like is preferably used. The sound insulating material reflects and blocks sound, and is preferably made of rubber mat, polyethylene, or the like.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following examples, the drawings are appropriately simplified or modified for the sake of explanation, and the dimensional ratios, shapes, etc. of each part are not necessarily drawn accurately.

FIG. 1 is a schematic front view of an electric drive unit 10 having a soundproof structure according to one embodiment of the present invention, viewed from the front side of a vehicle. FIG. and a portion where the soundproof cover 14 is arranged. The electric drive unit 10 is a drive unit for an electric vehicle, and is a horizontal type drive unit such as FF type (front engine front wheel drive type), and accommodates an electric motor and a transaxle used as a driving force source inside. A case 16 is provided. The case 16 includes a bottomed cylindrical first motor case portion 20 , a cylindrical second motor case portion 22 , and a bottomed cylindrical gear case portion 24 . An electric motor is accommodated inside the first motor case portion 20 and the second motor case portion 22 , and a transaxle is accommodated inside the gear case portion 24 . The transaxle includes a reduction gear device that reduces the speed of rotation of the electric motor, a differential gear device that distributes the power to the left and right driving wheels, and the like, and functions as a power transmission device. In this embodiment, the electric drive unit 10 having this transaxle corresponds to a vehicle power transmission device. Note that the left-right direction of the vehicle in FIG. 1 and the like is the opposite of the left-right direction of the vehicle itself when viewed from the front side of the vehicle.

The exterior component 12 incorporates an actuator, specifically an electric motor, of the SBW device that electrically operates the parking lock mechanism according to the operation of a shift lever, a parking operation switch, or the like. The parking lock mechanism includes a parking gear provided on the transaxle countershaft or the like, and a lock pole that meshes with the parking gear to prevent rotation. By meshing with the gear, it mechanically locks the drive wheel so that it cannot rotate through a countershaft or the like. The exterior component 12 includes a pair of case members 30 and 32 housing the electric motor and the like, and is mounted on the vehicle front side portion of the case 16 with a plurality of mounting bolts 34 . In FIG. 2, the electric motors and the like housed inside the case members 30 and 32 are omitted.

The soundproof cover 14 is arranged in a portion of the case 16 where noise such as gear noise is generated, and is for suppressing the diffusion of the noise to the outside. In the position, it is arranged in the vehicle front side portion of the case 16 . That is, there is a hollow space 40 between the case 16 and the exterior component 12, and noise generated from the case 16 resonates in the space 40 and is amplified. It is positioned within the space 40 and arranged to prevent resonance. Specifically, after attaching the soundproof cover 14 to the case 16 , the exterior component 12 is attached to the case 16 so as to partially overlap with the soundproof cover 14 .

The soundproof cover 14 includes a support plate 42 made of synthetic resin, a sound absorbing material 44 provided on the inner surface of the support plate 42, i.e., the surface facing the case 16, and the outer surface of the support plate 42, i.e., the surface facing the exterior component 12. and a sound insulating material 46 that 3 is a perspective view of the soundproof cover 14 seen from the front side of the vehicle, which is the exterior component 12 side, and FIG. 4 is a perspective view of the soundproof cover 14 seen from the rear side of the vehicle, which is the electric drive unit 10 side. The soundproof cover 14 is fixed to the case 16 via a plurality of mounting bolts 48 provided on the support plate 42 . The soundproof cover 14 is attached to the case 16 so that the support plate 42 as a whole is substantially parallel to the outer peripheral surface 54 of the case 16 and the back surface 52 of the exterior component 12 .

As is clear from FIG. 4, the sound absorbing material 44 is provided separately at a plurality of locations (two locations in the embodiment), and the annular second sound insulating material 50 is provided around each of the sound absorbing materials 44. is provided. The two sound absorbing members 44, the sound insulating members 46, and the two second sound insulating members 50 are fixed to the support plate 42 by fixing means such as an adhesive. The sound insulating material 46 has a block shape, and as is clear from FIG. is filled with a sound insulation material 46. - 特許庁The tip surfaces of the two second sound insulating members 50 are also brought into close contact with the outer peripheral surface 54 of the case 16 over substantially the entire circumference. The support plate 42 has a flat shape or an uneven shape corresponding to the shape of the back surface 52 or the outer peripheral surface 54 so that the tip surfaces of the sound insulating material 46 and the second sound insulating material 50 are brought into close contact with the back surface 52 or the outer peripheral surface 54, respectively. ing. It is also possible to adopt a flat plate-shaped support plate 42 by making the end surface shape of the sound insulating material 46 and the second sound insulating material 50 into a flat shape or an uneven shape corresponding to the shape of the back surface 52 or the outer peripheral surface 54 . The sound absorbing material 44 is sheet-like and thinner than the second sound insulating material 50 in height, but the sound absorbing material 44 can be provided with a thickness substantially equal to the height of the second sound insulating material 50 . The sound absorbing material 44 is sound absorbing urethane foam or the like, and the sound insulating material 46 and the second sound insulating material 50 are sound insulating rubber mats or the like. In FIGS. 3 and 4, the sound insulating material 46 and the second sound insulating material 50 are hatched so that the sound insulating material 46, the second sound insulating material 50, and the sound absorbing material 44 can be easily distinguished. The material 44 is provided with a large number of fine deformed circles.

In the soundproof structure of the electric drive unit 10 of this embodiment, a part of the soundproof cover 14 is arranged in the space 40 between the case 16 and the exterior component 12, and the soundproof cover 14 is supported. A sound insulating material 46 is provided on the outer surface of the plate 42 so as to be in contact with the back surface 52 of the exterior component 12 , so noise emitted from the case 16 is absorbed by the sound absorbing material 44 provided on the inner surface of the support plate 42 . On the other hand, since the sound insulating material 46 exists between the support plate 42 and the exterior component 12, deterioration of noise due to resonance is suppressed, and noise diffusion is appropriately prevented regardless of the presence of the exterior component 12. can do. Further, since a part of the soundproof cover 14 is arranged in the space 40 between the case 16 of the electric drive unit 10 and the exterior component 12, for example, the exterior component 12 is covered. Compared with the case where a soundproof cover is provided, the configuration is compact and advantageous in terms of space.

As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, this is only one embodiment, and the present invention can be implemented in a mode in which various modifications and improvements are added based on the knowledge of those skilled in the art. can be done.

10: Electric drive unit (vehicle power transmission device) 12: Exterior part 14: Soundproof cover 16: Case 40: Space part 42: Support plate 44: Sound absorbing material 46: Sound insulating material 52: Back surface

Claims (1)

A soundproof structure for a vehicle power transmission device, wherein a soundproof cover having a sound absorbing material provided on the inner surface of a support plate is attached to the outside of a case of the vehicle power transmission device in such a manner that the sound absorbing material faces the case. ,
An exterior part is arranged outside the case with a space therebetween, and at least part of the soundproof cover is arranged in the space,
A soundproof structure for a vehicle power transmission device, wherein a soundproof material is provided on an outer surface of the support plate of the soundproof cover so as to be in contact with a back surface of the exterior component.

Images