JP2869680B2 - Car power unit support structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power unit support structure for a motor vehicle, and more particularly to a power unit support structure for a motor vehicle having a power plant frame.

[0002]

2. Description of the Related Art Conventionally, a power unit including an engine and a transmission mounted on the front of a vehicle body and a differential mounted on the rear side of the vehicle body have a U-shaped cross section having a large bending rigidity and a flexibility against a screw. Rigidly connected through the power plant frame prevents the irregular swinging movement around the transverse axis passing through the engine support caused by the torque reaction of the power unit from being differentially transmitted, improving the ride comfort A known power unit support structure is known (see JP-A-56-28053). In this conventional power unit support structure, a power unit and a differential are attached to a cross member via respective mounts. Therefore, the entire drive train system including the power unit, the drive shaft, the power plant frame, and the differential is supported by the mount of the power unit and the mount of the differential.

[0003]

However, in the above-described conventional power unit support structure, the mounting position of the power unit to the cross member by mounting the power unit is relatively forward of the power unit, so that the entire drive train system is held at both ends. Become supportive. Therefore, when the engine vibrates due to the vertical movement of the vehicle body, a large load acts on the mount of the power unit. Furthermore, since the support is provided at both ends, a relatively large load acts on the differential mount. For this reason, it is necessary to harden the rubber of the differential mount. However, if the rubber is hardened, the differential noise increases, which is a problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a power unit support structure for an automobile which reduces a load acting on a mount of the power unit and reduces differential noise. The purpose is.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a power unit for a motor vehicle having a rigid frame connecting a power unit and a differential, wherein the power unit and the differential are respectively mounted on a vehicle body via mounts. In the support structure,
The power unit mount is disposed between the center of gravity of the entire drive train system including the power unit, the differential and the frame, and the center of gravity of the power unit.

In the present invention configured as described above,
Since the power unit mount is located between the center of gravity of the entire drive train system and the center of gravity of the power unit, the load value of the drive train system shared by the differential mount can be reduced, and the dynamic load acting on the power unit mount can be reduced. Since the load value is relatively small, the load acting on the mount of the power unit can be reduced.

[0007]

1 to 4 show an embodiment of the present invention.
This will be described with reference to FIG. FIG. 1 is a side view showing an embodiment of a power unit support structure for a vehicle according to the present invention, FIG. 2 is a plan view of FIG. 1, FIG. 3 is a front view of a power unit mount, and FIG. 4 is a plan view of a power unit mount. .

1 and 2, reference numeral 1 denotes the entire drive train system, and the drive train system 1 is configured as follows. That is, the power unit 2 is mounted on the front part of the vehicle body.
It comprises an engine 3 and a transmission 4. A differential 5 is mounted on the rear of the vehicle,
The power unit 2 and the differential 5 are connected by a power plant frame 6. The power plant frame 6 is formed to have a U-shaped cross section that is opened laterally, has high bending rigidity, and has flexibility against torsion. The power unit 2 and the differential 5 are connected by a drive shaft 7, and the power of the engine 3 is transmitted to the rear wheels via the drive shaft 7 and the differential 5.

As shown in FIG. 1, a point A indicates the position of the center of gravity of the drive train system 1 including the power unit 2, the differential 5, the power plant frame 6 and the drive shaft 7, while a point B indicates the engine 3 2 shows the position of the center of gravity of the power unit 2 composed of the power unit 2 and the transmission 4. The power unit 2 is attached to a cross member 11 by a mount 10.
1 is further fixed to a vehicle body (not shown). The mount 10 of the power unit 2 has a flange 10a and a rubber 10b, as shown in FIGS.
And is fixed to the cross member 11 via the. Similarly, the differential 5 is attached to a cross member 13 by a mount 12, and the cross member 13 is further fixed to a vehicle body (not shown).

Further, the mount 10 of the power unit 2
Is located between point A, which is the position of the center of gravity of the drive train system 1, and point B, which is the position of the center of gravity of the power unit 2. It is desirable that the mount 10 of the power unit 2 be further disposed closer to the point B which is the center of gravity of the power unit than the center between the points A and B as shown in FIG.

Next, the operation of the above embodiment will be described.
First, by disposing the mount 10 of the power unit 2 relatively near the point A which is the position of the center of gravity of the drive train system 1, the mount 10 of the power unit 2 supports most of the entire load of the drive train system 1. And the load value of the drive train system 1 shared by the mount 12 of the differential 5 decreases. Therefore, the rubber of the mount 12 of the differential 5 can be softened, and the differential noise can be reduced.

On the other hand, the mount 10 of the power unit 2
Is disposed near point B, which is the position of the center of gravity of the power unit 2, so that even if the power unit 2 vibrates due to the vertical movement of the vehicle body, the value of the dynamic load acting on the mount 10 of the power unit 2 is relatively small. Therefore, the load acting on the mount 10 of the power unit 2 can be reduced.

Although the above embodiment is of a type in which the power unit is directly connected to the engine and the transmission, the present invention is also applicable to a type in which the engine and the transmission are connected via a drive shaft. In the above embodiment, the power unit is constituted by the engine and the transmission, but only the engine may correspond to the power unit. in this case,
Point B, which is the center of gravity of the power unit, matches the center of gravity of the engine alone.

[0014]

As described above, in the present invention,
The load acting on the mount of the power unit can be reduced, and the differential noise can be reduced.

[Brief description of the drawings]

FIG. 1 is a side view showing one embodiment of a power unit support structure for an automobile according to the present invention.

FIG. 2 is a plan view of FIG. 1;

FIG. 3 is a front view of a power unit mount.

FIG. 4 is a plan view of a power unit mount.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drive train system 2 Power unit 3 Engine 4 Transmission 5 Differential 6 Power plant frame 7 Drive shaft 10 Mount 12 Mount

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B60K 5/02 B60K 5/12 B60K 17/06 B60K 17/16

Claims (2)

(57) [Claims] 1. A power unit supporting structure for a vehicle having a rigid frame connecting a power unit and a differential and mounting the power unit and the differential to a vehicle body via mounts, respectively, wherein an entire drive train system including the power unit, the differential and the frame is provided. A power unit support structure for an automobile, wherein the power unit mount is disposed between the center of gravity of the power unit and the center of gravity of the power unit. 2. A power unit support structure for an automobile according to claim 1, wherein the mount of the power unit is disposed closer to the center of gravity of the power unit than the center between the center of gravity of the entire drive train system and the center of gravity of the power unit. .