JP2000177402A - Mount structure of driving unit for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driving unit mount structure for a vehicle, capable of removing a mount pin from a mount member positively when a load is inputted at the time of head-on collision without removing the mount pin from the mount member at the time of ordinary driving. SOLUTION: This mount structure is formed so that a driving unit may be supported by the frame member 12 of a vehicle body through a mount member 24, wherein the mount member 24 is provided with a metallic outer cylinder 26 fixed to the frame member 12, a metallic inner cylinder 27 and mount rubber 28, and a mount pin 23 connected to the driving unit is forcibly-inserted into the inner cylinder 27 from the rear side. A stopper part 27a protruding in the direction of an outer diameter is mounted on an opposite end part to the inserted side of the mount pin 23 of the inner cylinder 27. When the front collides and a load equal to a prescribed value or larger acts on the mount pin 23 in the coming-off direction, the stopper part 27a of the inner cylinder 27 comes into contact with the outer cylinder 26 and the mount pin 23 comes off from the inner cylinder 27, thus it is possible to remove the driving unit from a vehicle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure for supporting a drive unit such as a front differential or a power unit (engine, transmission) on a frame member of a vehicle body via a mount member, and more particularly, to a drive unit for a vehicle body frame member. And a structure for detachably supporting the device.

[0002]

2. Description of the Related Art In a cab-over type four-wheel drive vehicle or the like, a differential case (front differential case) is disposed at the front of the vehicle. An example of this type of differential case supporting structure is disclosed in Japanese Utility Model Laid-Open No. 6-71248.
In this support structure, as shown in FIG. 1, a cross member 2 extending in the vehicle width direction is connected between a pair of side frames 1, 1 arranged on both sides of a front portion of the vehicle, and a differential case is connected to the cross member 2. 3 is supported at the front via a mount rubber 4. The inner ends of the two brackets 5 and 6 are connected to the rear part of the differential case 3. The outer ends of the brackets 5 and 6 are mounted on the side frames 1 and 1 with mounting rubbers 7 and 8. Through the support.

[0003] Incidentally, it is desired that the front structure of the vehicle body be configured to absorb and reduce the impact force by crashing at the time of a forward collision of the vehicle. In this case, in order to enhance the effect of absorbing and mitigating the impact force, it is necessary to make the crash stroke at the front of the vehicle body as long as possible. However, the conventional structure for supporting the differential case 3 has a structure in which the front and rear portions of the differential case 3 are firmly supported on a frame member of the vehicle such as the cross member 2 and the side frame 1. Since the case 3 itself was made robustly, a sufficient crash stroke could not be secured when the vehicle collided forward.

[0004]

Accordingly, the applicant of the present application fixed an arm extending in the vehicle width direction to the rear portion of the differential case, and attached both ends of the arm in the vehicle width direction to the vehicle body via a cylindrical mount rubber. At the same time, an outer cylinder of the cylindrical mount rubber is fixed to the vehicle body, and a mount pin press-fit into the cylindrical mount rubber from the rear of the vehicle body is fixed to the arm (Japanese Patent Application No. 9-31).
No. 5848). And when the load is input to the rear of the vehicle body with respect to the differential case, the mount pin can be detached rearward with respect to the cylindrical mount rubber,
It is possible to take a long crash stroke at the time of a frontal collision of the vehicle.

In this case, the mount pins are press-fitted into the inner rubber portion of the inner cylinder of the cylindrical mount rubber. However,
If this press-fit load is large, even if a load is input to the differential case from the rear of the vehicle body, the rubber part between the inner cylinder and the outer cylinder will only expand, and the mount pin will not come off the mount rubber. May be. If the press-fit load of the pin is set to a small value, the pin easily comes off the mount rubber, but this is not preferable because the pin may come off even during normal running.

Therefore, an object of the present invention is to prevent a mount pin from being detached from a mount member during normal running.
An object of the present invention is to provide a mounting structure of a vehicle drive unit in which a mount pin can be securely detached from a mount member at the time of load input such as a collision.

[0007]

In order to achieve the above object, the present invention provides a mount structure for supporting a drive unit on a frame member of a vehicle body via a mount member, wherein the mount member comprises a metal outer cylinder, It has a metal inner cylinder disposed at the center of the outer cylinder, and a mount rubber provided between the outer cylinder and the inner cylinder, and a mount pin is press-fitted into the inner cylinder from one side. A stopper portion is provided at an end of the inner cylinder opposite to the press-fit side of the mounting pin, the stopper portion protruding in an outer radial direction, the outer cylinder is connected to one of a frame member or a drive unit of the vehicle body, and the mount pin is connected to the vehicle body. Connected to the other of the frame member or the drive unit, the direction in which the mount pin is removed is set to be substantially the same as the direction in which the drive unit is relatively displaced with respect to the frame member of the vehicle body at the time of a collision of the vehicle, A vehicle wherein the mount pin can be detached from the inner cylinder by causing the stopper portion of the inner cylinder to come into contact with the outer cylinder or the mount rubber when a load in the release direction exceeding a predetermined value acts on the mount pin. Provided is a mounting structure for a driving unit.

During normal running, if a relative displacement occurs between the frame member of the vehicle body and the drive unit, a load may be applied to the mount pin in the pull-out direction. However, since the load in the pull-out direction at this time is smaller than the press-fit load between the mount pin and the inner cylinder, the mount rubber between the outer cylinder and the inner cylinder only slightly expands, and the mount pin does not detach from the inner cylinder. . Since the mount pin is securely held by the inner cylinder, the mount member can exhibit a sufficient cushioning function due to its rubber elasticity.

On the other hand, when a load in the direction of withdrawal exceeding a predetermined value acts on the mount pin due to a vehicle collision or the like, the mount rubber between the outer cylinder and the inner cylinder extends until the stopper of the inner cylinder hits the side edge of the outer cylinder. . Since the elongation of the mounting rubber is limited by the contact between the stopper and the outer cylinder, a load is applied directly between the inner cylinder and the mounting pin, and even if the press-fit load between the mounting pin and the inner cylinder is high, the mounting pin Surely comes out of the inner cylinder. As a result, the drive unit can be largely displaced and does not hinder the vehicle from crashing, and the crash stroke can be made longer. Note that the stopper portion has almost the same function even when it comes into contact with the vicinity of the outer peripheral portion of the mount rubber where the deformation is relatively small, instead of the outer cylinder.

In the first aspect, a stopper portion is provided at the end of the inner cylinder opposite to the press-fit side of the mount pin so as to protrude in the outer diameter direction. A stopper may be provided at the end of the inner tube to protrude in the inner diameter direction, and the stopper may be brought into contact with the inner cylinder or mount rubber so that the mount pin can be detached from the inner cylinder.

In the present invention, the driving unit includes:
In addition to the differential case, a power unit such as an engine or a transmission may be used, and any type of power unit may be used as long as it can interfere with a vehicle crash at the time of a collision. In the case of the differential case, since the vehicle is displaced rearward due to a forward collision, the mounting pin may be pulled out of the vehicle rearward.However, in the case of a power unit, the mounting unit may drop downward due to a frontal collision. In this case, the mounting pin comes out downward.

Further, the direction of press-fitting of the mount pins does not need to be exactly the same as the direction of displacement of the drive unit, and may be slightly inclined. That is, the drive unit is not always displaced in a fixed direction depending on the input direction and the arrangement position of the drive unit at the time of a forward collision, so that the pin may be set in the direction in which the pin can be smoothly removed.

The mounting rubber is preferably a cylindrical mounting rubber. Since the cylindrical mount rubber has a structure in which the rubber is evenly interposed between the outer cylinder and the inner cylinder all around, the degree of freedom in setting the spring constant is high. Therefore, a suitable spring constant can be obtained, and transmission of vibration of the drive unit to the vehicle body can be suppressed.

Further, the mount pin is press-fitted into the inner cylinder, but if the inner cylinder and the pin are in metal contact, rattling occurs and it is difficult to set a press-fit load. Therefore, it is desirable to provide a rubber portion inside the inner cylinder and press-fit a pin into the rubber portion. In this case, play can be eliminated, and the degree of freedom in setting the press-fit load is high.

When the stopper is provided on the inner cylinder, it is desirable to extend a portion covering the stopper integrally from the mount rubber and the rubber inside the inner cylinder. In this case, the rubber coating prevents the inner cylinder from rusting, so that painting is not required.

The stopper provided on the inner cylinder or the outer cylinder may be formed in a flare shape or may be constituted by a plurality of claw pieces projecting radially. Further, the stopper portion does not need to be integral with the inner cylinder or the outer cylinder, and a separate stopper member may be fixed to the inner cylinder or the outer cylinder.

[0017]

2 and 3 show an example in which the present invention is applied to a support structure for a differential case. The support structure of the differential case of this embodiment is applied to a cab-over type four-wheel drive vehicle, and is indicated by an arrow Fr.
Indicates the front of the vehicle.

A pair of side frames 10, 10 extending in the front-rear direction of the vehicle body are arranged at both side positions at the front of the vehicle. On the lower surface side of these side frames 10, 10,
As shown in FIG. 3, the sub-frame 11 is fastened by bolts B. The sub-frame 11 is formed, for example, in a substantially H-shape in plan view, and connects a pair of side members 12 extending substantially along the side frames 10 in the vehicle front-rear direction and front portions of the side members 12 to each other. And a cross member 13 extending in the vehicle width direction. The front end of the side member 12 is fastened to the lower surface of the front end of the side frame 10 by the bolt B. The side member 12 of the sub-frame 11 is bent downward as shown in FIG. 3, and both ends of the cross member 13 are connected to the front inclined portion 12 a of the side member 12. Side member 12
A bent portion 12c is formed between the inclined portion 12a and the substantially horizontal central portion 12b, and the bent portion 12c forms a fragile portion that is easily bent at the time of a forward collision of the vehicle. In addition,
The side member 12 can also be used for supporting one end of a suspension arm (not shown) of a front suspension.

A cross member 14 is fixed between the side frames 10 and 10 at the rear of the subframe 11 so as to extend in the vehicle width direction. The rear end of the subframe 11 is connected to the cross member 14 and the side frame 10. Are fastened by bolts B in the vicinity of the connecting portion.

A differential case 15 is mounted on the sub-frame 11. The differential case 15 is provided with a differential gear for transmitting the rotational force of the probe shaft 16 to the axle 17. This embodiment is a structure applied to a cab-over type vehicle, and a differential case 15 is placed on one side in the vehicle width direction from the center position in the vehicle width direction by an appropriate dimension (the left side of the vehicle in the figure).
Offset to The above differential case 1
5 is connected to the cross member 13 of the sub-frame 11 via a cylindrical mount member 18 and a bracket 19. In this case, the support shaft 20 penetrating the mount member 18 is fixed to the bracket 19 in the vehicle width direction.

An arm 22 extending in the vehicle width direction is fixed to a rear portion of the differential case 15 via a bracket 21. In this embodiment, the arm 22 is formed of, for example, a cylindrical pipe material from the viewpoint of weight reduction. At the left and right ends of the arm 22, mounting pins 2 protruding forward.
3 and 23 are respectively fixed. In this embodiment, 1
Although the arm 22 is composed of two continuous arms 22, two arms 22 on the left and right may be attached to the rear of the differential case 15.

The mounting pin 23 is mounted on the sub-frame 1
The mounting member 24 fixed to the first side member 12 is press-fitted from the rear of the vehicle body. As shown in FIG. 4, the mount member 24 includes a cylindrical metal outer cylinder 26 fixed to the side member 12 via a bracket 25, and a metal inner cylinder 27.
And a mount rubber 28 vulcanized and bonded between the outer cylinder 26 and the inner cylinder 27, and a rubber portion 29 is fixed inside the inner cylinder 27 by vulcanization bonding. The rubber part 29
May be formed integrally with the mount rubber 28. Inner cylinder 27
A flared stopper 27a is integrally formed on the front end of the mount pin 23, that is, on the end opposite to the press-fit side of the mount pin 23 (see FIG. 5). In this embodiment, the stopper 2
7a is larger than the inner diameter of the outer cylinder 26,
The front and back surfaces of 7a are covered with cover portions 28a and 29a integrally extended from the mount rubber 28 and the rubber portion 29. The stoppers 2 are formed by the covering portions 28a and 29a.
The coating of 7a becomes unnecessary. Mount pin 23 is rubber part 2
9 is press-fitted inside, so that the play between the inner cylinder 27 and the mount pin 23 can be absorbed and the mount pin 2
3 can be set freely.

As described above, since the mount pin 23 is press-fitted into the mount member 24 from the rear of the vehicle body, when the vehicle encounters a frontal collision, the mount pin 23 is displaced rearward as the differential case 15 is displaced rearward. 24, the rear part of the differential case 15 can be detached. At this time, the inner cylinder 27
Is displaced rearward with the mount pin 23, and the mount rubber 28 is greatly deformed.
6, the stopper 27a of the inner cylinder 27 abuts against the side edge of the outer cylinder 26 to restrict the elongation of the mounting rubber 28. Therefore, as shown in FIG.
3 can be reliably removed.

When the differential case 15 is offset to one side from the center position of the vehicle body as described above, the left and right mount pins 23 do not always move immediately after a forward collision. The direction of the mount pin 23 may be slightly inclined in the horizontal direction or the vertical direction in consideration of the displacement characteristics.

Next, the operation of the mount structure having the above configuration will be described. In the normal traveling state, as shown in FIGS. 2 and 3, the front part of the differential case 15 is supported by the cross member 13 of the sub-frame 11 via the cylindrical mount member 18, and the rear part of the differential case 15 is cylindrical. The sub-frame 11 via the mounting member 24
, The suitable spring constant is obtained by the action of the mount members 18 and 24, and the transmission of the vibration of the differential case 15 to the vehicle body can be suppressed. Also, since the support shaft 20 of the front mount member 18 is arranged in the horizontal direction, the front part of the differential case 15 does not displace in the front-rear direction, while the rear mount member 24 is provided with the mount pin 23 from the rear. Since it is press-fitted, the rear part of the differential case 15 does not displace in the left-right direction. Therefore, there is no possibility that the mount pin 23 will fall off the mount member 24 in response to a load input during normal running.

When the vehicle makes a forward collision, an impact force F acts on the front portion of the side frame 10 as shown in FIGS.
While the side frame 10 crashes, the impact force F also acts on the sub-frame 11, and the front part of the sub-frame 11, especially the cross member 13, is displaced rearward. Therefore, the differential case 15 connected to the cross member 13 is also displaced rearward. On the other hand, since the rear end of the sub-frame 11 is connected to the portion of the side frame 10 that does not crash,
Is bent at the fragile portion 12c, and the cylindrical mount member 24 fixed to the side member 12 tries to maintain its position. Therefore, the arm 22 connected to the rear of the differential case 15 moves relatively rearward with respect to the mount member 24, and the mount pin 23
Attempts to leave behind from 4. At this time, since the inner cylinder 27 is integrally displaced rearward by the press-fit load of the mount pin 23, the mount rubber 28 is stretched, but the stopper portion 27a provided on the inner cylinder 27 hits the side edge of the outer cylinder 26, and Since the extension of the pin 28 is limited, the mount pin 23 can be easily detached from the inner cylinder 27. as a result,
The differential case 15 can be freely displaced rearward, the crash stroke at the front of the vehicle can be lengthened, and the shock absorbing effect can be enhanced. The connecting pin of the propeller shaft 16 may be broken so that the propeller shaft 16 can be detached from the differential case 15 when the differential case 15 is detached.

In the above embodiment, the stopper 2 is attached to the inner cylinder 27.
7a is provided, and the stopper pin 27a is brought into contact with the outer cylinder 26 to make it easier to pull out the mount pin 23, but the present invention is not limited to this. For example, even if the outer diameter of the stopper portion 27a is reduced so that the stopper portion 27a does not contact the outer cylinder 26 but the vicinity of the outer peripheral portion of the mount rubber 28 where the deformation is relatively small, substantially the same operation and effect can be obtained.

FIG. 9 shows a second embodiment of the present invention. In addition,
The same parts as those in FIG.
In this embodiment, a stopper 26a projecting in the inner diameter direction is integrally provided at an end of the outer cylinder 26 on the press-fit side of the mount pin 23, and the stopper 26a hits the edge of the inner cylinder 27, and the extension of the mounting rubber 28 is increased. Is limited. In this case, the same operation and effect as those of the first embodiment can be obtained. Note that the stopper 26a of the outer cylinder 26 does not necessarily have to contact the inner cylinder 27, and has substantially the same function even when the stopper 26a contacts the vicinity of the inner peripheral portion of the mount rubber 28 where the deformation is relatively small.

The present invention can be applied not only to the mounting structure of a differential case but also to the mounting structure of a power unit, for example, as disclosed in Japanese Patent Application No. 9-315549 previously proposed by the present applicant. That is, a frame member extending in the vehicle front-rear direction is disposed substantially at the center of the vehicle front portion in the vehicle width direction, and the front and rear portions of the power unit are supported by this frame member via a mount member. Is bent downward. Mount pins protrude upward on both sides of the power unit, and cylindrical mount members are fixed to side frames arranged on both sides in the vehicle width direction at the front of the vehicle body, and the mount pins are placed below the center of these mount members. Press more. The power unit is displaced downward as the frame member bends and deforms downward at the time of a frontal collision of the vehicle, so that the mount pin can be detached downward from the mount member.
Also in this case, a stopper may be formed on the inner cylinder or the outer cylinder of the mount member so that the mount pin can be easily removed.

The mounting structure of the present invention is not limited to the example in which the mounting pin is fixed to the drive unit and the outer cylinder is fixed to the vehicle body frame as in the embodiment. The same function is obtained even if the cylinder is fixed to the drive unit side. Furthermore, the drive unit of the present invention is not limited to being mounted on the front part of the vehicle body, and may be mounted on the rear part of the vehicle body such as a rear engine. Again,
The drive unit may be detached from the vehicle body at the time of load input such as at the time of a collision.

[0031]

As is apparent from the above description, claim 1
According to the invention described in the above, provided a stopper portion projecting in the outer radial direction at the end of the inner cylinder opposite to the press-fit side of the mount pin,
When a load in the release direction exceeding a predetermined value acts on the mount pin, the stopper pin of the inner cylinder comes into contact with the outer cylinder or the mount rubber, so that the mount pin can be detached from the inner cylinder. At the time of load input, the pin can be reliably detached from the mount member, and the drive unit can be displaced greatly, so that the crash of the vehicle body is not obstructed and the crash stroke can be lengthened. Also, even if the press-fit load between the mount pin and the mount member is set to a large value, the mount pin can be securely removed in the event of a collision, so that the mount pin can be securely held by the mount member during normal running, and the mount pin may be accidentally detached. Absent.

According to the second aspect of the present invention, a stopper portion is provided at the end of the outer cylinder on the press-fit side of the mounting pin so as to protrude in the inner diameter direction. Since the mount pin can be detached from the inner cylinder by contacting the stopper portion of the outer cylinder with the inner cylinder or the mount rubber, the same operation and effect as the first aspect of the invention can be obtained.

[Brief description of the drawings]

FIG. 1 is a plan view of an example of a conventional differential case support structure.

FIG. 2 is a plan view of an example in which the present invention is applied to a differential case support structure.

FIG. 3 is a side view of FIG. 2;

FIG. 4 is a partially enlarged sectional view of the mount structure of FIG. 2;

FIG. 5 is a perspective view of an inner cylinder of the mount structure of FIG. 4;

6 is a cross-sectional view of the mount structure of FIG. 4 when deformed.

FIG. 7 is a plan view of the differential case supporting structure shown in FIG. 2 at the time of a crash.

FIG. 8 is a side view of FIG. 7;

FIG. 9 is a sectional view of a second embodiment of the mount structure of the present invention.

[Explanation of symbols]

 Reference Signs List 10 side frame 11 sub-frame 15 differential case (drive unit) 23 mounting pin 24 mounting member 26 outer cylinder 27 inner cylinder 27a stopper portion 28 mount rubber 29 rubber portion

Claims (2)

[Claims] 1. A mounting structure for supporting a drive unit on a frame member of a vehicle body via a mounting member, wherein the mounting member includes a metal outer cylinder, a metal inner cylinder disposed at a central portion of the outer cylinder, A mount rubber provided between the outer cylinder and the inner cylinder; a mount pin is press-fitted into the inner cylinder from one side; an end of the inner cylinder opposite to the press-fit side of the mount pin; The outer cylinder is connected to one of the frame member or the drive unit of the vehicle body, and the mount pin is connected to the other of the frame member or the drive unit of the vehicle body. The disengagement direction is set to be substantially the same as the direction in which the drive unit is relatively displaced with respect to the frame member of the vehicle body in the event of a vehicle collision, and a disengagement load greater than a predetermined value acts on the mount pin. Time, the stopper portion of the inner cylinder abuts the outer tube or mount rubber, the mount structure of the vehicle drive unit, characterized in that a detachable mount pin from the outer cylinder. 2. A mounting structure for supporting a drive unit on a frame member of a vehicle body via a mounting member, wherein the mounting member includes a metal outer cylinder, a metal inner cylinder disposed at a central portion of the outer cylinder, A mount rubber provided between the outer cylinder and the inner cylinder; a mount pin is press-fitted into the inner cylinder from one side; The stopper part which protrudes in the direction is provided,
The outer cylinder is connected to one of the frame member or the drive unit of the vehicle body, and the mount pin is connected to the other of the frame member or the drive unit of the vehicle body. The direction is set to be substantially the same as the direction of relative displacement with respect to the frame member, and when a load in the release direction of a predetermined value or more is applied to the mount pin, the stopper portion of the outer cylinder abuts on the inner cylinder or mount rubber. A mount structure for a vehicle drive unit, wherein a mount pin is detachable from an inner cylinder.