JPH086680Y2 - Power plant frame structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a power plant frame structure for connecting a power unit and a rear differential.

(Prior Art) Conventionally, a power unit such as an engine installed in the front part of a vehicle body and a rear differential installed in the rear part of the vehicle body are connected by a power plant frame at a position covering a propeller shaft to reduce engine vibration and reduce It is known that the wind-up vibration of the rear differential caused by the torque reaction force from the wheel is suppressed (see Japanese Patent Laid-Open No. 56-28053).

(Problems of the prior art) In the conventional power plant frame structure described above, since the cross section of the power plant frame is substantially U-shaped, the wind-up vibration of the rear differential caused by the driving force generated by the power unit causes Acceleration performance can be significantly improved by suppressing it with strong bending rigidity, while the roll moment of the power unit (rotation around the propeller shaft) can be absorbed appropriately by the weak torsional rigidity of the power plant frame. Since the roll moment is not transmitted to the rear differential, noise and vibration can be significantly reduced.

However, because the power plant frame has a substantially U-shaped cross section, the high frequency vibrations such as the rear differential transmitted to the power plant frame and the gear vibration generated by the power unit are amplified, and the level of the vehicle interior noise is extremely deteriorated. Has been discovered.

(Object of the Invention) In view of the above-mentioned problems, the present invention is a power plant that does not impair the effects that can be obtained by making the cross section of the power plant frame substantially U-shaped without causing an increase in weight or the like. It is intended to provide a frame structure.

(Effects of the Invention) In order to solve the above-mentioned problems, the present invention connects a power unit installed in the front part of a vehicle body, a rear differential installed in the rear part of the vehicle body, and the power unit and the rear differential, A power plant frame having a propeller shaft that transmits a driving force to a rear differential, and a power plant frame that covers the propeller shaft and rigidly connects the power unit and the rear differential, and has a substantially U-shaped cross section. In addition to being made of a damping steel plate material, it is made up of an outer frame and an inner frame, and both frames form a closed cross section.

(Advantages of the Invention) As described above, the present invention makes the power differential of the rear differential wind-up vibration by making the power plant frame into a substantially U-shaped cross section with the vibration damping steel plate material and having the closed cross sectional shape. Accelerating performance can be significantly improved by suppressing it with strong bending rigidity of the frame, while the roll moment of the power unit (rotation around the propeller shaft) is absorbed by the soft torsional rigidity of the power plant frame. As a result, the roll differential is not transmitted to the rear differential, and noise and vibration can be greatly reduced, and it is possible to play without impairing the effect of the power plant frame with a substantially U-shaped cross section, and also to reduce the cross section. The high-frequency vibration generated by the U-shape causes an increase in weight, etc. It can be prevented without causing any trouble.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view of a vehicle chassis having a power plant frame, and FIG. 2 is a side view thereof.

A power unit 1 including an engine, a mission, etc., which is installed in a front portion of an automobile, is attached to a front cross member 3 by a usual method via a pair of engine mounts 2 arranged in parallel in the vehicle width direction.

The front cross member 3 is supported by a body frame 7 via an elastic member (not shown) by a known method. The control arm 4 is swingably supported by the front cross member 3 and the control arm 4 is supported by the control arm 4. The front wheel 6 is supported.

Further, the control arm 4 is supported by the vehicle body frame 7 via a balancer 5.

The power unit 1 is connected by a rear differential 8 and a propeller shaft 9 installed at the rear of the automobile.

The rear differential 8 is supported by the rear cross member 10 via an elastic member 11, and is used as an accelerator shaft.
It is configured to transmit the driving force to the rear wheel 13 by 12.

The rear cross member 10 is supported by the body frame 7 via an elastic member (not shown) by a known method. The control arm 14 is swingably supported by the rear cross member 10, and the control arm 14 is supported by the control arm 14. A rear wheel 13 is supported.

Further, the control arm 14 is supported by the vehicle body frame 7 via a balancer 15.

The power unit 1 and the rear differential 8 are connected by a power plant frame 16 to form a power plant body A.

3 is an enlarged plan view of the power plant frame 16, FIG. 4 is a side view of the power plant frame 16, and FIGS. 5 (a) to 5 (e).
Are cross-sectional views (AA line, BB line, C line) of FIG. 4, respectively.
-C line, DD line, EE line) is shown. Hereinafter, the structure of the power plant frame 16 will be described with reference to these drawings.

The power plant frame 16 is formed of a vibration damping steel plate, and a pair of bolt through holes 17 are provided at the front end and the rear end of the frame 16, respectively. As shown in FIG. , 20 to connect the frame 16 to the power unit 1 and the rear differential 8 and
Fixed at 19,21.

As shown in FIG. 5, the power plant frame 16 is composed of an outer frame 24 and an inner frame 25, and the inner frame 25 is the power plant frame 16
In order to form triangular closed cross-sections 22a and 22b at the upper part and the lower part, respectively, they are fixed to the inner surface of the outer frame 24 by welding or the like. Further, as shown in FIGS. 5A to 5E, the triangular closed cross sections 22a, 22b have their areas gradually changing in the longitudinal direction of the power plant frame 16, and the front and rear of the power plant frame 16 At both ends, the closed cross section 22a,
There is no 22b and it is a completely open section. As described above, by forming the closed cross sections 22a and 22b by dividing the upper part and the lower part of the power plant frame 16, the installation space for the propeller shaft 9 is secured, and both end parts of the power plant frame 16 are opened. By doing so, the connection of the frame 16 to the power unit 1 and the rear differential 8 is facilitated.

A plurality of weight reducing holes 23 are provided on the side surface 24a of the outer frame 24 of the power plant frame 16, and a drain hole 26 is provided on the lower surface 24b of the outer frame 24.
Is provided. Further, the side surface 25a of the inner frame 25
There are several drainage passages 27 between the outer frame 24 and the side surface 24a of the outer frame 24.
It flows down through the passage 27 to the side of the closed section 22b, and the drain hole 26
It is designed to flow from the outside.

Incidentally, the damping material may be filled in the closed cross sections 22a, 22b formed by the outer frame 24 and the inner frame 25 described above.

As described above, by forming a closed cross section between the outer frame and the inner frame, the rigidity can be increased without increasing the weight, and at the front and rear ends, the outer frame and the inner frame are overlapped and opened. By forming the cross section, the connection to the power unit and the rear differential is facilitated and the mounting rigidity is improved. According to the present embodiment, since the power plant frame is made of a damping steel plate and has a closed cross section having a substantially U-shaped cross section, it is possible to suppress the increase of the plate thickness and increase the rigidity. In addition to suppressing the noise, it is possible to suppress the generation of noise due to resonance at a high level by increasing the natural frequency.

[Brief description of drawings]

1 is a plan view of a chassis of an automobile having a power plant frame, FIG. 2 is a side view of the same, FIG. 3 is an enlarged plan view of a power plant frame, FIG. 4 is a side view of the same, and FIG. 5 (a). -(E) are AA line, BB line, and C of FIG. 4, respectively.
-C line, DD line, EE line sectional view. 1 ... Power unit, 8 ... Rear differential, 9
… Propeller shaft, 16… Powerplant frame.

Claims (1)

[Scope of utility model registration request] 1. A power unit installed at a front portion of a vehicle body,
A rear differential installed at the rear of the vehicle body, the power unit and the rear differential are connected to each other, a propeller shaft for transmitting a driving force to the rear differential is covered, and the power unit and the rear differential are rigidly connected. In a power plant frame having a substantially U-shaped cross section, the power plant frame is made of a damping steel plate material and is made up of an outer frame and an inner frame. A power plant frame structure characterized by being configured to form.