JPH02117472A - Body mount construction in front frame - Google Patents

Abstract

PURPOSE:To improve its vibration isolating performance and/or mounting rigidity, by forming a taper portion at a supporting hole formed through a front frame, the internal diameter of which taper portion gradually increases, and also forming a trunpet-shaped portion at a spacer to be inserted into the supporting hole, so that the trunpet-shaped portion corresponds to the taper portion. CONSTITUTION:Upper and lower bracket plates 2, 3 are arranged at the upper and lower sides of the body mount portion A of a front frame 1. A cylindrically- shaped spacer 5 is passed through the supporting hole 4 of the body mount portion A. Besides, a pair of upper and lower mount rubbers 6 are interposed between the upper and lower bracket plates 2, 3. The upper and lower bracket plates 2, 3 are fastened together by a bolt 7. In this case, a taper portion 8, the internal diameter of which increases gradually from its middle to end portion in its vertical direction, is formed at the supporting hole 4. A trunpet- shaped portion 9 which corresponds to the taper portion 8 is formed at the spacer 5.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a body mount structure that connects a front frame and a body.

[Prior Art and Problems to be Solved] In a frame-equipped automobile, the frame and body are usually connected.
As shown in FIG. 4, this is done through a mounting rubber a. For example, in the case of the illustrated body mount structure, the upper bracket plate b is connected to the body and the lower bracket plate is bolted to the upper bracket plate b. A pair of upper and lower cylindrical mount rubbers C and C are interposed between the frame d and C.
The frame and body are joined by sandwiching them. By coupling the frame and the body through the mount rubber a in this manner, it is possible to block vibrations transmitted from the drive system and suspension system to the body through the frame. In addition, in the case of the illustrated type of body mount structure, the upper and lower bracket plates b,
A cylindrical spacer e interposed between the frame d and the support hole e of the frame d

[is inserted through the mount rubber a, a,
Inside this spacer e, there are upper and lower bracket plates b,
The hole (pole) g that fixes c is inserted. By the way, in the case of a front frame provided at the front part of a vehicle, an engine is usually mounted on the frame, and a steering gear and the like are also attached thereto. Therefore, in the body mount of the front frame,
As mentioned above, in addition to the ability to absorb engine vibrations and prevent them from being transmitted to the body, the vehicle must also have characteristics that can suppress lateral vibration of the frame and ensure rigidity when mounting the steering gear. . However, in order to suppress the lateral vibration of the frame,
The spring constant of the mount rubber must be high, which deteriorates the vibration isolation properties of the mount rubber. In addition, if the spring constant of the mount rubber is lowered to ensure vibration isolation, the rigidity of the steering gear installation cannot be ensured.In other words, in order to achieve both of the above two characteristics, the mount rubber must be Because it is necessary to have completely contradictory properties, it is extremely difficult to appropriately achieve both. Therefore, in the past, the actual situation was to set the spring constant of the mount rubber within a range where both characteristics could be compromised. The present invention was devised under the above circumstances, and has characteristics that can prevent vibrations of the drive system from being transmitted to the body, and characteristics that can ensure rigidity in mounting the steering gear. The object is to provide a body mount structure in a front frame configured to achieve both. [Means for Solving the Problems] In order to solve the above problems, the present invention takes the following technical measures. That is, a cylindrical spacer inserted into a support hole of the front frame is inserted between a pair of body-side bracket plates located vertically at a predetermined interval with a front frame having a predetermined thickness in between, and this spacer and the above-described A cylindrical elastic body is interposed between the support hole and the front frame, and the pair of bracket plates are bolted by bolts inserted into the spacer. In the body mount structure of the front frame in which the front frame is coupled to the body by fastening, the support hole is provided with a tapered part whose inner diameter gradually increases from the middle part toward the end in the thickness direction, and At a position corresponding to the tapered portion of the spacer,
A trumpet-shaped portion whose outer diameter gradually increases from the middle portion located within the support hole toward the end portion is provided.

[Action and effect]

A cylindrical spacer that is inserted into the support hole of the front frame is interposed between each bracket plate of the body example located above and below with the front frame in between, and the space between this spacer and the support hole is The upper and lower ends of the cylindrical elastic body inserted into the annular space are sandwiched between the front plate and the upper and lower bracket plates. Therefore, the front frame is connected to the body with elastic bodies interposed between each bracket plate and spacer, and this elastic body absorbs vibrations from the engine etc. mounted on the frame. This can prevent it from being transmitted to the body. By the way, when the front frame oscillates laterally (behavior in the horizontal direction), this behavior is suppressed by the elastic repulsive force of the elastic body interposed in the annular space between the support hole and the spacer. Lateral vibration of the front frame is allowed within a range where it can be elastically deformed. However, in the present invention, the above-mentioned spacer is provided with a trumpet-shaped part whose outer diameter gradually increases from the middle part located in the support hole toward the end part, thereby 1. The constant can be substantially increased. Therefore, the lateral vibration of the front frame can be appropriately suppressed, and as a result, the mounting rigidity of the steering gear attached to the front frame can be ensured. This is because at the location where the trumpet-shaped portion is provided, the distance between the inner circumferential surface of the support hole and the spacer becomes smaller, and the volume of the annular space is reduced. In this case, the capacity of the elastic body interposed between the front frame and the spacer in the annular space can be reduced. If the capacity of the elastic body is reduced, the amount of elastic deformation of the elastic body is reduced, so this is not acceptable. Lateral vibration of the front frame is also reduced. That is, the spring constant of the elastic body in the horizontal direction is substantially increased, and as a result, as described above, the lateral vibration of the front frame can be suppressed and the rigidity of the mounting of the steering gear can be ensured. Additionally, by providing the trumpet-shaped portion, the vertical length of the portion of the elastic body that is sandwiched between the front frame and each bracket plate and mainly elastically supports the front frame in the vertical direction can be reduced. do not have,
Further, since the trumpet-shaped portion is provided at a position corresponding to the tapered portion, an appropriate vertical distance between the trumpet-shaped portion and the front frame can be ensured. Therefore, the spring constant of the mount rubber in the vertical direction is approximately constant, and the problem of deterioration of vibration isolation does not occur. In this manner, the present invention can substantially increase the horizontal spring constant of the elastic body while keeping the vertical spring constant substantially constant. Therefore, it is possible to achieve both the characteristics required for the front frame body mount structure to prevent the transmission of engine vibrations to the body, and the characteristics to ensure rigidity in mounting the steering gear.

[Explanation of Examples]

Embodiments of the present invention will be specifically described below with reference to the drawings. The present invention relates to a body mount structure for coupling a front frame l and a body as shown in FIG. 3, for example. The front frame l is placed at the front of the vehicle, and usually
It is composed of two plate members, an upper plate 1a and a lower plate 1b, whose edges are joined to each other to form a box-shaped cross-sectional structure. Further, although not shown in the drawings, an engine is mounted on the front frame l, and a steering gear is attached to the rear of the frame. In the case of the illustrated frame-shaped front frame 1, body mount parts A provided at each of its four corners are respectively coupled to the body by the following body mount structure. As shown in FIG. 1, above and below the body mount portion A of the front frame 1, there are an upper bracket plate 2 connected to the body, and below these are located at a predetermined interval with the front frame l in between. A lower bracket plate 3 bolted to the upper bracket plate 2 is arranged. A support hole 4 is provided in the body mount portion A, and a cylindrical spacer 5 interposed between the upper and lower bracket plates 2 and 3 is inserted into the support hole 4. Moreover, a pair of upper and lower cylindrical mount rubbers 6.6 is interposed between the upper and lower bracket plates 2.3, and these are
The cylinder body is inserted into the annular space between the support hole 4 and the spacer 5, and the base end is inserted into the bracket plate 2.3.
and the front frame 1. and,
The front frame 1 and the body are connected by bolting the lower bracket 3 to the upper bracket plate 2 using bolts 7 inserted into the spacer 5 from the lower bracket plate 3 side. Therefore, the vertical vibration that the front frame 1 receives from the engine is absorbed by the mount rubber 6.
．． 6, the above vibration can be absorbed by the front frame 1.
This can prevent the air from being transmitted to the body via the Now, in the present invention, the support hole 4 of the front frame l is provided with a tapered part 8 whose inner diameter gradually increases from the middle part toward the end part in the thickness direction. and,
An example in which the spacer 5 is provided with a generally conical trumpet-shaped portion 9 whose outer diameter gradually increases from the intermediate portion located within the support hole 4 toward the end portion, corresponding to the tapered portion 8. As shown in FIG. 1, a pair of the tapered portions 8 are provided symmetrically above and below the support hole 4. On the other hand, the above-mentioned trumpet-shaped portion 9 is provided above the spacer 5 at a position corresponding to the upper tapered portion 8 and has an inclination approximately the same as the inclination angle of the tapered portion 8 . Therefore, in the upper part of the spacer 5 and the support hole 4 where the trumpet-shaped part 9 is provided, the spacer 5 and the support hole 4
The distance between the inner circumferential surface and the inner circumferential surface of the annular space is narrowed, and the volume of the annular space at this portion is reduced. In this case, the capacity of the mount rubber 6 interposed between the front frame 1 and the spacer 5 can be reduced. When the capacity of the mount rubber 6 is reduced in this manner, the amount of elastic compression deformation thereof is reduced, and the permissible lateral vibration (behavior in the direction of arrow H in FIG. 1) of the front frame l is also reduced. In other words, the spring constant of the mount rubber 6 in the horizontal direction (arrow H direction) is substantially increased, and as a result, the front frame 1
lateral vibration can be appropriately suppressed. therefore,
The mounting of the steering gear on the front frame 1 can increase rigidity. Further, by providing the trumpet-shaped portion 9, the portions of the mount rubber 6.6 that are sandwiched between the front frame 1 and each bracket plate 2.3 and that mainly elastically support the front frame 1 in the vertical direction are The length in the direction does not become small.Furthermore, since the trumpet-shaped portion 9 is provided at a position corresponding to the tapered portion 8, an appropriate vertical distance between the trumpet-shaped portion 9 and the front frame 1 can be ensured. Therefore, the spring constant of the mount rubber 6 in the vertical direction is substantially constant, and there is no problem of deterioration of vibration isolation. In this way, in the body mount structure of this example, the spring constant of the mount rubber 6 in the vertical direction can be kept substantially constant while the spring constant in the horizontal direction can be increased. Therefore, it is possible to appropriately prevent lateral vibration of the front frame 1 and increase the rigidity of the mounting of the steering gear without deteriorating the vibration-proofing properties capable of blocking the transmission of engine vibrations to the body. By the way, the scope of the present invention is not limited to the above-mentioned embodiments. For example, as shown in FIG. In this case, the horizontal spring constant of the mount rubber 6 can be increased to further improve the rigidity of the steering gear installation.

[Brief explanation of drawings]

FIG. 1 is a diagram showing main parts of an embodiment of the present invention, and FIG.
2 is a diagram showing another embodiment, FIG. 3 is a plan view of the front frame of the embodiment, and FIG. 4 is a diagram showing a conventional example. . l...Front frame, 2.3...Bracket plate, 4...Support hole, 5...Spacer, 6...
Elastic body (mount rubber), 7... bolt, 8... tapered part, 9... trumpet-shaped part.

Claims (1)

[Claims] (1) A cylindrical spacer inserted into the support hole of the front frame is inserted between a pair of body-side bracket plates located vertically at a predetermined distance with a front frame having a predetermined thickness in between; A cylindrical elastic body is interposed between the support hole and the bracket plate and the front frame, and a bolt is inserted between the pair of bracket plates and the spacer. In a body mount structure for a front frame in which the front frame is joined to the body by bolting, the support hole is provided with a tapered part whose inner diameter gradually increases from the middle part toward the end in the thickness direction, At a position corresponding to the tapered portion of the spacer,
A body mount structure for a front frame, characterized in that a trumpet-shaped portion is provided, the outer diameter of which gradually increases from the middle portion located within the support hole toward the end portion.