JP2023093142A - strut mount - Google Patents

Abstract

To provide a strut mount capable of reducing a thickness dimension of a vehicle body-side member.SOLUTION: A strut mount includes: a vehicle body-side member 10 connected to a vehicle body D; a rod-side member 20 to which a tip of a piston rod PR is connected; and an elastic member 30 disposed between the vehicle body-side member 10 and the rod-side member 20. As an inner diameter d1 of a through hole OP on the vehicle body BD is larger than an inner diameter D1 of a lower cylindrical portion 14, a region S1 where an input from a bound damper BB1 and reaction force from the vehicle body BD are overlapped, is formed in a case when the input from the bound damper BB1 is acted on the vehicle body-side member 10, and the input and the reaction force can be canceled for the region S1. As a result, generation of shearing stress on the vehicle body-side member 10 can be suppressed.SELECTED DRAWING: Figure 1

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strut mount, and more particularly to a strut mount capable of suppressing shear stress from occurring in a vehicle body member.

A strut mount interposed between a vehicle body and a piston rod of a shock absorber is known (Patent Document 1).

JP 2016-102506 (for example, FIG. 3 etc.)

However, the conventional strut mount described above has a problem that shear stress tends to be generated in the vehicle body side member due to the load received during running.

This problem will be described with reference to FIG. FIG. 3 is a vertical cross-sectional view of a conventional strut mount 1000. FIG. As shown in FIG. 3 , the strut mount 1000 includes a vehicle body side member 1010 connected to the vehicle body BD, a rod side member 1020 connected to the tip of the piston rod PR, and between the vehicle body side member 1010 and the rod side member 1020. and an elastic member 1030 interposed between.

While the vehicle is running, the strut mount 1000 receives an input (arrow B) from the bound bumper (not shown) of the shock absorber acting on the lower surface of the vehicle body side member 1010, and reacts to the input from the vehicle body BD (arrow B). A) is applied to the upper surface of the vehicle body side member 1010 .

In this case, the input from the bound bumper (arrow B) is applied to the central portion of the vehicle body member 1010 centering on the piston rod PR, while the reaction force from the vehicle body BD (arrow A) is applied to the outer edge of the vehicle body member 1010. acted on in part.

Therefore, the area between the area where the input from the bound bumper (arrow B) acts and the area where the reaction force (arrow A) from the vehicle body BD acts (in FIG. 3, the hatched area, hereinafter There is a problem that shear stress is generated in the "intermediate region 1010a").

SUMMARY OF THE INVENTION An object of the present invention is to provide a strut mount capable of suppressing the occurrence of shear stress in a vehicle body member.

In order to achieve this object, the strut mount of the present invention is interposed between a vehicle body and a piston rod of a shock absorber. and an elastic member interposed between the vehicle-body-side member and the rod-side member, the lower surface of the vehicle-body-side member outside an area where the bound bumper of the shock absorber can abut. The diameter is made larger than the inner diameter of the region of the upper surface of the vehicle body side member to which the vehicle body is connected.

According to the strut mount of claim 1, the vehicle body side member connected to the vehicle body, the rod side member to which the tip end of the piston rod is connected, and the elastic member interposed between the vehicle body side member and the rod side member. , and the outer diameter of the area where the bound bumper of the shock absorber can contact on the lower surface of the vehicle body side member is made larger than the inner diameter of the area on the upper surface of the vehicle body side member where the vehicle body is connected, so that the bound bumper is applied to the vehicle body side member, an area where the input from the bound bumper and the reaction force from the vehicle body overlap is formed, and the input and the reaction force can be offset by the overlapping area. As a result, it is possible to suppress the occurrence of shear stress in the vehicle body side member.

According to the strut mount of claim 2, in addition to the effect of the strut mount of claim 1, the vehicle body side member includes the upper cylindrical portion surrounding the rod side member and the lower end side of the upper cylindrical portion. a bottom portion projecting radially inward from the lower end of the upper cylinder portion; an arm portion projecting radially outward from the lower end side of the upper cylinder portion and connected to the upper surface of the vehicle body; and an upper cylinder projecting from the lower surface of the arm portion. and a lower tubular portion formed in a substantially concentric tubular shape, and the inner diameter of the lower tubular portion is larger than the outer diameter of the upper tubular portion, so that the input from the bound bumper and the reaction force from the vehicle body overlap. can be formed on the arms of the vehicle body side member. Therefore, the input and the reaction force can be offset by the amount of the overlapped area, and it is possible to suppress the occurrence of shear stress in the vehicle body side member.

According to the strut mount of claim 3, in addition to the effect of the strut mount of claim 2, the vehicle body side member has a lower surface of the bottom and at least a lower surface of the arm that is radially inner than the lower tubular portion. Being formed on one flat surface, the input from the bounce bumper can be distributed to both the bottom and arms. Therefore, for example, it is possible to suppress the occurrence of shear stress in the vehicle-body-side member compared to a configuration in which the input from the bounce bumper mainly acts on the lower surface of the arm.

Further, at least the lower surface of the arm portion radially inner than the lower cylindrical portion is formed as a flat surface. It is possible to easily secure an area where the input from the bounce bumper and the reaction force from the vehicle body overlap.

According to the strut mount of claim 4, in addition to the effect of the strut mount of claim 3, the arm of the vehicle body side member is formed in a plate shape with the upper surface and the lower surface substantially parallel. Compared to a configuration in which the upper surface and the lower surface are non-parallel, it is possible to efficiently cancel out the input from the bound bumper and the reaction force from the vehicle body.

According to the strut mount of claim 5, the through hole through which the piston rod of the shock absorber is inserted is formed, and the ring member connected to the lower surface of the vehicle body side member is provided, and the input from the bound bumper is received by the ring member. It can be made to act on the vehicle body side member via.

In this case, the outer diameter of the upper surface of the ring member is made larger than the inner diameter of the region of the upper surface of the vehicle body side member to which the vehicle body is connected. In addition, even if the outer diameter of the upper surface of the bound bumper is smaller than the inner diameter of the area where the vehicle body is connected on the upper surface of the vehicle body side member, the area where the input from the bound bumper and the reaction force from the vehicle body overlap. can be formed. Therefore, the input and the reaction force can be offset by the amount of the overlapped area, and it is possible to suppress the occurrence of shear stress in the vehicle body side member.

According to the strut mount of claim 6, in addition to the effect of the strut mount of claim 5, since the outer diameter of the upper surface of the ring member is larger than the outer diameter of the lower surface, the input from the bound bumper is reduced. , the ring member can efficiently expand to a region where the reaction force from the vehicle body overlaps. Also, the weight of the ring member can be reduced.

(a) is a top view of a strut mount according to a first embodiment of the present invention, and (b) is a vertical sectional view of the strut mount taken along line Ib-Ib of FIG. 1(a). (a) is a longitudinal sectional view of a strut mount in a second embodiment, and (b) is a longitudinal sectional view of a strut mount in a third embodiment. FIG. 10 is a vertical cross-sectional view of a conventional strut mount;

Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. FIG. 1(a) is a top view of the strut mount 1 according to the first embodiment of the present invention, and FIG. 1(b) is a vertical cross-sectional view of the strut mount 1 taken along line Ib-Ib of FIG. 1(a). be. In addition, in FIG.1(b), the attachment state to the vehicle body BD is illustrated.

As shown in FIG. 1, the strut mount 1 is interposed between the vehicle body BD and the piston rod PR of the shock absorber. Specifically, the strut mount 1 is interposed between the vehicle body side member 10 connected to the vehicle body BD, the rod side member 20 connected to the tip of the piston rod PR, and the vehicle body side member 10 and the rod side member 20. and an elastic member 30 .

The vehicle body side member 10 and the rod side member 20 are made of a metal material, and the elastic member 30 is made of a rubber-like elastic body. In this embodiment, the vehicle body side member 10 is formed from an aluminum alloy casting, and the rod side member 20 is formed from a steel material.

The vehicle body side member 10 includes an upper tubular portion 11 formed in a tubular shape (substantially cylindrical shape centered on the axis O) surrounding the rod side member 20, and an upper tubular portion 11 projecting radially inward from the lower end side of the upper tubular portion 11. A bottom portion 12 is formed, an arm portion 13 is formed so as to protrude radially outward from the lower end side of the upper cylindrical portion 11 and is connected to the upper surface of the vehicle body BD, and the upper cylindrical portion 11 is protruded from the lower surface of the arm portion 13. and a lower tubular portion 14 formed in a concentric tubular shape (substantially cylindrical shape centered on the axis O).

A disk-shaped upper cover member 40 is arranged at the upper end of the upper cylinder part 11 , and an elastic member 30 is arranged between the upper cover member 40 and the bottom part 12 in a state of being compressed in the direction of the axis O. A circular through-hole is formed through the center of the upper lid member 40, and a nut N1 fastened to the tip of the piston rod PR is inserted through this through-hole.

In addition, before the upper cover member 40 is arranged, a bent piece protrudes from the upper end of the upper cylindrical portion 11 over the entire circumference, and by bending the bent piece radially inward, the upper cover member 40 is crimped and fixed to the upper end of the upper tubular portion 11 .

A circular through-hole is formed through the center of the bottom portion 12, and the piston rod PR is inserted through this through-hole. In addition, in the present embodiment, the thickness dimension of the bottom portion 12 (the dimension in the direction of the axis O) is made larger than the thickness dimension of the arm portion 13 .

The arm portion 13 is formed in a substantially triangular shape when viewed from above, and has a flat plate shape with a substantially constant thickness dimension (axis O direction dimension). Fastening holes 13a are formed through the arm portion 13 at a plurality of locations (three locations in this embodiment) that are equally spaced in the circumferential direction, and a nut N2 is fastened to the tip of a bolt B2 that is inserted through each of the fastening holes 13a. Thus, the vehicle body BD is connected (fastened and fixed) to the upper surface of the arm portion 13 .

In this embodiment, the upper surface of the arm portion 13 is a flat surface perpendicular to the axis O. As shown in FIG. A circular through hole OP is formed through the vehicle body BD, and the inner diameter of the through hole OP is d1 (hereinafter referred to as "inner diameter d1"). In consideration of the dimensional tolerance of the through hole OP, the upper surface of the arm portion 13 is provided with a flat surface that can come into contact with the lower surface of the vehicle body BD in a range wider than the inner diameter d1 (on the axis O side). Further, the upper surface of the arm portion 13 and the outer peripheral surface of the upper tubular portion 11 are smoothly connected by the arcuate cross-sectional shape.

The lower surface of the arm portion 13 is flush with the lower surface of the bottom portion 12 at least at the lower surface radially inward of the lower cylindrical portion 14 (on the axis O side). A flat surface substantially parallel to the upper surface of the is formed.

A concave portion is formed in the inner peripheral surface of the lower tubular portion 14, and a protrusion of the bound bumper BB1 of the shock absorber is fitted into the concave portion, whereby the bound bumper BB1 is held in the lower tubular portion 14. That is, the upper surface of the bounce bumper BB1 can come into contact with the lower surface of the bottom portion 12 and the lower surface of the arm portion 13 .

The inner diameter of the lower tubular portion 14 has a minimum value of D1 (hereinafter referred to as "inner diameter D1"), and this inner diameter D1 is larger than the outer diameter of the upper tubular portion 11, It is made larger than the inner diameter d1 of OP (d1<D1).

The rod-side member 20 has a tubular portion through which a circular through hole is formed, and an overhanging portion formed by projecting radially outward from the tubular portion, and is inserted into the through hole of the tubular portion. A nut N1 is fastened to the tip of the piston rod PR, which is connected (fastened and fixed) to the tip of the piston rod PR. An elastic member 30 is vulcanization-bonded to the overhanging portion of the rod-side member 20 over the entire circumference.

According to the strut mount 1, the outer diameter of the area on the lower surface of the vehicle body side member 10 where the bound bumper BB1 of the shock absorber can abut is larger than the inner diameter of the area on the upper surface of the vehicle body side member 10 to which the vehicle body BD is connected. be done. Specifically, the minimum inner diameter D1 of the lower tubular portion 14 is made larger than the inner diameter d1 of the through hole OP of the vehicle body BD (d1<D1).

As a result, when the input from the bound bumper BB1 acts on the vehicle body side member 10 as the vehicle travels, the input from the bound bumper BB1 and the reaction force from the vehicle body BD overlap in a region (marked in FIG. 1). A region indicated by "S1" (hereinafter referred to as "region S1") is formed, and the input and the reaction force can be offset by the region S1. As a result, the occurrence of shear stress in the vehicle body side member 10 (arm portion 13) can be suppressed.

In the vehicle body side member 10, the lower surface of the bottom portion 12 and the lower surface of the arm portion 13 at least radially inward of the lower cylindrical portion 14 are formed to be flush with each other. It can be distributed to both the arm 13 and the arm 13 . Therefore, for example, the lower surface of the bottom portion 12 is positioned above the lower surface of the arm portion 13, and a step is formed between the two, so that the input from the bound bumper BB1 mainly acts on the lower surface of the arm portion 13. The strength required for the arm 13 can be reduced compared to the configuration. As a result, the thickness dimension of the vehicle body side member 10 (arm portion 13) can be suppressed.

Further, at least the entire lower surface of the arm portion 13 radially inward of the lower cylinder portion 14 is formed as a flat surface, so that a region where the upper surface of the bound bumper BB1 can abut can be secured. Therefore, for example, at least the bottom surface of the arm portion 13 radially inner than the lower cylindrical portion 14 has a step (a portion of the bottom surface is positioned above the remaining portion, and the remaining portion is the bound bumper BB1). ), it is possible to easily secure the area S1 where the input from the bound bumper BB1 and the reaction force from the vehicle body BD overlap.

Since the arm portion 13 is formed in a plate-like shape with the upper surface and the lower surface substantially parallel to each other, the input from the bound bumper BB1 and the input from the vehicle body BD are more effective than the configuration in which the upper surface and the lower surface are non-parallel, for example. It is possible to efficiently cancel out the reaction force.

In this embodiment, as described above, the thickness dimension of the bottom portion 12 (dimension in the direction of axis O) is made larger than the thickness dimension of the arm portion 13 (dimension in the direction of axis O), and the upper surface of the arm portion 13 and the upper cylindrical portion It is smoothly connected to the outer peripheral surface of 11 by an arcuate cross-sectional shape. Therefore, by utilizing the strength of the bottom portion 12, the strength of the root portion of the arm portion 13 (the portion on the side of the upper cylindrical portion 11) can be ensured.

Next, a second embodiment will be described. In the first embodiment, the bound bumper BB1 is held by the lower cylindrical portion 14 of the vehicle body member 10, but the bound bumper BB2 in the second embodiment is externally fixed to the piston rod PR of the shock absorber. be done. That is, the outer diameter of the upper surface of the bound bumper BB2 in the second embodiment is made smaller than the outer diameter of the upper surface of the bound bumper BB1 in the first embodiment. In this embodiment, the outer diameter of the upper surface of the bound bumper BB2 is made smaller than the inner diameter d1 of the through hole OP of the vehicle body BD.

FIG. 2(a) is a longitudinal sectional view of the strut mount 201 in the second embodiment, and corresponds to FIG. 1(b). In addition, the same code|symbol is attached|subjected to the part same as 1st Embodiment mentioned above, and the description is abbreviate|omitted.

As shown in FIG. 2( a ), the strut mount 201 includes a ring member 250 made of a metal material. are concatenated by In addition, in this embodiment, the ring member 250 is formed from an aluminum alloy casting.

The ring member 250 is a disk-shaped member having a circular through hole formed through the center thereof, and the piston rod PR is inserted through the through hole. The upper and lower surfaces of the ring member 250 are flat surfaces parallel to each other.

The dimension of the outer diameter of the upper surface of the ring member 250 is D2 (hereinafter referred to as "outer diameter D2"). It is made larger than the inner diameter d1 of OP (d1<D2). Therefore, the input from the bound bumper BB2 can be applied to the vehicle body side member 10 (the bottom portion 12 and the arm portions 13) through the ring member 250.

As a result, even if the outer diameter of the upper surface of the bound bumper BB2 is smaller than the inner diameter d1 of the through hole OP of the vehicle body BD (the inner diameter of the region of the upper surface of the vehicle body side member 10 to which the vehicle body BD is connected), the bound bumper BB2 is bound. A region S2 can be formed in which the input from the bumper BB2 and the reaction force from the vehicle body BD overlap. Therefore, the input and the reaction force can be offset by the area S2, and the occurrence of shear stress in the vehicle body side member 10 (arm portion 13) can be suppressed.

The strut mount 201 according to the second embodiment has a configuration in which the ring member 250 is arranged (connected) to the strut mount 1 according to the first embodiment, so the strut mount 1 according to the first embodiment can be used. Therefore, for example, when the specifications of the shock absorber are changed (the bound bumper BB1 is changed to the bound bumper BB2), it is unnecessary to design a new strut mount different from the strut mount 1 in accordance with the change. .

The outer diameter D2 of the upper surface of the ring member 250 is made larger than the outer diameter of the lower surface. Therefore, the input from the bounce bumper BB2 can be efficiently expanded by the ring member 250 to a region where it overlaps with the reaction force from the vehicle body BD. In addition, the ring member 250 can be made lighter by chamfering the side surfaces.

Next, a third embodiment will be described. FIG. 2(b) is a longitudinal sectional view of the strut mount 301 in the third embodiment, and corresponds to FIG. 1(b). In addition, the same code|symbol is attached|subjected to the same part as each embodiment mentioned above, and the description is abbreviate|omitted.

As shown in FIG. 2(b), the strut mount 301 has the same configuration as the strut mount 1 in the first embodiment, except that the lower tubular portion 14 is omitted. The ring member 350 has the same configuration as the ring member 250 in the second embodiment, except that a protrusion 351 is added.

A protrusion 351 protrudes from the upper surface of the ring member 350 over the entire circumference. It is press-fitted and fixed to the lower surface of (bottom portion 12). Thereby, falling off of the ring member 350 can be suppressed as compared with the case of adhesion. In addition, the protrusion part 351 may be intermittently formed in the circumferential direction.

The present invention has been described above based on the embodiments, but the present invention is not limited to the above-described embodiments, and it is easily understood that various modifications and improvements are possible without departing from the scope of the present invention. It can be inferred.

The numerical values given in the above embodiment are examples, and it is naturally possible to employ other numerical values. Similarly, the number of arrangements for each configuration is arbitrary.

In each of the above embodiments, the case where the vehicle body side member 10 and the ring members 250 and 350 are formed by casting has been described, but they may be formed by cutting. Alternatively, the ring members 250 and 350 may be formed from a resin material such as PPA or PPS.

In the second or third embodiment, the structure in which the ring members 250 and 350 are connected (arranged) to the vehicle body member 10 by adhesion or press-fitting has been described, but another structure may be employed.

For example, a structure in which a female thread is formed on the inner peripheral surface of the through hole of the bottom portion 12 and a male thread is provided on the outer peripheral surface of the projecting portion 351 of the ring member 350 and they are screwed together may be employed. Alternatively, for example, a bent piece protrudes from the lower surface of the arm 13 over the entire circumference (or intermittently in the circumferential direction), and the bent piece bent radially inward abuts the inclined surfaces of the ring members 250 and 350. A contact structure (that is, a structure substantially the same as a structure in which the upper cover member 40 is crimped and fixed by a bent piece protruding from the upper end of the upper cylindrical portion 11) may be used.

1, 201, 301 strut mount 10 vehicle body side member 11 upper tubular portion 12 bottom portion 13 arm portion 14 lower tubular portion D1 inner diameter of lower tubular portion 20 rod side member 30 elastic member 250, 350 ring member D2 outer diameter of upper surface of ring member BD Body d1 Body through hole inner diameter PR Piston rods BB1, BB2 Bound bumper

Claims (6)

In the strut mount interposed between the vehicle body and the piston rod of the shock absorber,
a vehicle body-side member connected to the vehicle body;
a rod-side member to which the tip of the piston rod is connected;
an elastic member interposed between the vehicle body side member and the rod side member;
An outer diameter of a region of the lower surface of the vehicle body side member where the bound bumper of the shock absorber can abut is larger than an inner diameter of a region of the upper surface of the vehicle body side member to which the vehicle body is connected. strut mount. The vehicle body side member is
an upper tubular portion formed in a tubular shape surrounding the rod-side member;
a bottom formed by projecting radially inward from the lower end of the upper cylinder;
an arm portion projecting radially outward from the lower end side of the upper cylindrical portion and having an upper surface connected to the vehicle body;
a lower tubular portion protruding from the lower surface of the arm portion and formed in a tubular shape substantially concentric with the upper tubular portion;
2. The strut mount according to claim 1, wherein the inner diameter of said lower tubular portion is larger than the outer diameter of said upper tubular portion. 3. The strut mount according to claim 2, wherein the vehicle body side member has a flat surface in which a lower surface of the bottom portion and a lower surface of the arm portion radially inner than the lower cylindrical portion are flush with each other. 4. The strut mount according to claim 3, wherein the arm portion of the vehicle body side member is formed in a plate-like shape having an upper surface and a lower surface substantially parallel to each other. a ring member having a through-hole through which the piston rod of the shock absorber is inserted and connected to the lower surface of the vehicle body-side member;
The strut mount according to any one of claims 1 to 4, wherein the outer diameter of the top surface of the ring member is larger than the inner diameter of the region of the top surface of the vehicle body side member to which the vehicle body is connected. 6. The strut mount according to claim 5, wherein the outer diameter of the upper surface of the ring member is larger than the outer diameter of the lower surface.

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