JP2003118342A - Fork member for supporting shock absorber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fork member for supporting a shock absorber, which does not require a high fastening force, can securely hold the shock absorber, and can save weight and cost by saving materials. To do. SOLUTION: A member constituting a suspension device, an arm 13 having an arc shape, and a holder 14 formed integrally with an upper end of the arm 13 and capable of accommodating and holding a lower end of a shock absorber 21 are provided. A pin connecting portion 15 provided at the lower end of the arm portion 13 and having a connecting pin with the lower link member 40. The fork member for supporting a shock absorber, wherein the inner peripheral surface of the holder 14 is 3-10.
a fork member for supporting a shock absorber, wherein the fork member is formed on a rough surface of a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock absorber supporting fork member (hereinafter referred to as "fork member") for connecting a shock absorber constituting a vehicle suspension device to a lower link member, and more specifically to a shock. The present invention relates to a structure of a holder portion that holds a lower end of an absorber.

[0002]

2. Description of the Related Art As shown in an example in FIG. 5, a suspension device includes a wheel support 30, a lower link member 40 and a compression rod 50, and a knuckle steering 60 to connect an upper link member 70 to a shock absorber. The strut member 20 including 21 is connected to the lower link member 30. The strut member 20 includes a shock absorber 21, a coil-shaped spring member 22 that is mounted on the shock absorber 21, and a fork member 10 that connects the shock absorber 21 and the lower link member 30. The fork member 10 employed in the suspension device is a known member for connecting the shock absorber 21 to the lower link member 40, and the arm portion 13
And a holder 14 and a pin connecting portion 15.
In the above structure, the arm portion 13 is a member that transmits the load and the external force from the lower link member 40 side to the shock absorber 21, and has a proof strength that opposes the transmitted load and the external force. The pin connecting portion 15 is a portion integrally formed with the lower end of the arm portion 13, and connects the lower end of the arm portion 13 holding the shock absorber 21 to the lower link member 40. The holder 14 is a portion integrally formed at the upper end of the arm portion 13, has a housing portion that can house and hold the lower end of the shock absorber 21, and the housing portion is provided with a known gripping means. It is a member that holds the lower end of the absorber 21. As the shock absorber 21 gripping means of the holder 14, for example, a known clamp having a C-shaped cross section is adopted. The shock absorber 21 is gripped by using the gripping force generated by accommodating the lower end of the shock absorber 21 in the accommodating portion of this clamp and tightening the open end of the accommodating portion with a known fastening means such as a bolt. ing. At this time, since the gripping force of the shock absorber 21 is determined by the tightening force of the bolt that fastens the clamp, a high tension bolt that enables a high tension setting to obtain a sufficient gripping force to prevent the shock absorber 21 from coming off. Etc. are used.

[0003]

The holder structure of the fork member described above has the following problems. That is, in the conventional holder of the fork member, the inner peripheral surface of the accommodating portion is formed as a smooth surface, so by fastening the open end of the accommodating portion with the high tension bolt, a uniform and large grip is formed on the entire inner peripheral surface. A high fastening force was required to grip the shock absorber, such as exerting force.

The present invention has been made in view of the above problems, and does not require a high fastening force by bolts and can securely grip the shock absorber, and it is possible to reduce the weight and cost by saving the material. An object of the present invention is to provide a shock absorber supporting fork member capable of performing the above.
An object is to increase the gripping force of the shock absorber by the holder of the fork member with a simple structure and prevent the shock absorber from coming off. The present invention provides a shock absorber supporting fork member for achieving at least any one of the above objects.

[0005]

In order to achieve the above object, the shock absorber supporting fork member of the present invention includes a holder having a C-shaped cross section which accommodates a lower end of the shock absorber and can be clamped by bolt fastening. 3 to 1 on the circumference
It is formed on the rough surface of 0a.

In the shock absorber supporting fork member described above, the rough surface in the holder is formed as a groove along the circumferential direction.

In the shock absorber supporting fork member described above, the rough surface is formed to have a chevron shape in cross section.

In the shock absorber supporting fork member described above, the upper surface of the holder is an inclined surface that gently intersects with the lower axial direction of the shock absorber housed in the holder, and the lower surface of the holder is formed. Is formed so as to have a saw-tooth shape in section, which is a substantially right-angled surface in a substantially orthogonal direction.

Further, in the shock absorber supporting fork member, the rough surface is formed with a non-uniform pitch.

In any one of the shock absorber supporting fork members described above, the shape of the joint surface between the arm portion and the holder is formed so that there is a difference in wall thickness between the upper portion and the lower portion of the holder. May be.

According to the shock absorber supporting fork member of the present invention configured as described above, it is possible to obtain a sufficient gripping force for gripping the shock absorber without introducing an excessive fastening force. . Therefore, it is not necessary to introduce high tension when fastening the bolts,
The risk of damaging the bolt can be avoided.

Further, because of the above-described structure, more design strength than necessary is not imparted, so that the material required for the entire fork member including the holder can be reduced, and the weight and cost can be reduced.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, one embodiment of a shock absorber supporting fork member (hereinafter referred to as "fork member") according to the present invention will be described in detail with reference to FIGS. Prior art fork member 10
Parts and portions having the same functions as those in FIG. The fork member 10 is integrally formed with an arc-shaped arm portion 13 having a substantially triangular cross-section in which the inner peripheral side 12 is thicker than the outer peripheral side 11, and a joint shape at the upper end of the arm portion 13 having a substantially triangular sectional shape. And a pin connecting portion 15 formed integrally with the lower end of the arm portion 13. Hereinafter, the holder 1 for holding the shock absorber
4 will be described.

<A> Holder Structure As the holder 14 of the fork member 10, a known gripping means such as a clamp having a C-shaped cross section as shown in FIG. The holder 14 is a vertically-oriented storage portion 14 that can store the lower end of the shock absorber 21.
Has 1. The accommodating portion 141 has an opening 142 in the vertical direction, and the inner diameter of the accommodating portion 141 can be reduced by narrowing the opening 142. Bolt holes 143 and 143 are formed on the same line at both ends forming the opening 142 of the holder 14. The inner diameter of the accommodating portion 141 can be reduced by inserting the bolt 144 from one of the holders 14 into the bolt holes 143 and 143 and screwing the bolt 144. The bolt holes 143 are provided at substantially the center of the holder 14, and are set so that uniform fastening force is generated between the holder lower portion 145 and the holder upper portion 146 when the bolts 144 are fastened.

<B> Receiving Section In the above-described structure of the holder 14, the accommodating section 141 has a rough inner surface to increase the frictional resistance of the lower end of the shock absorber 21 in the pull-out direction, thereby increasing the gripping force. Can be increased. Specifically, as shown in FIG. 3, a plurality of protrusions 148 are formed as rough surfaces on the inner peripheral surface of the housing 141. The protrusion 148 can be formed, for example, in a ring shape in the direction perpendicular to the axis of the housing 141. At this time, the rough surface may be formed by arranging a plurality of protrusions 148, which are independent from each other in a single line, or may be configured as a ring having a spiral shape in which a large number of protrusions 148 are connected in series. Good.

Further, in order to secure a sufficient gripping force for the roughness of the rough surface, in consideration of the thickness of the coating film layer 211 applied to the lower end of the shock absorber 21 for the purpose of rust prevention and the like. The minimum value is formed to 3a, and the maximum value is formed to 10a in consideration of workability described later. That is, the roughness range of the rough surface is preferably 3a to 10a. For more information,
Considering that the coating film thickness of the coating normally applied to the outer periphery of the shock absorber 21 is 12 μm on average, in order to prevent early slippage due to external force, at least a large roughness exceeding this coating film thickness is required. As (height of protrusion 148) H,
The minimum value requires 3a. Further, in consideration of the workability of the inner peripheral surface of the holder 14, the maximum value of the roughness range is set to 10a.
If it is set to 15a, which exceeds the roughness range of 10a, the load during cutting will be large, and the bite (blade for forming the rough surface) will be greatly damaged, and the machine capacity will be excessive. Defect occurs. Further, when the load of the cutting tool becomes large, vibration is generated, which may make it impossible to form a stable rough surface. Further, since the feed of the cutting tool is relatively increased with respect to the cutting rotation, the machining method becomes complicated and inefficient. A plurality of protrusions 14 forming a rough surface
As a specific shape of No. 8, for example, the cross section of the protrusion 148 is formed in a mountain shape in cross section such that the inclined surface facing the opening side of the upper holder 146 and the inclined surface facing the opening side of the lower holder 145 are symmetrical. You may. The protrusion 148 is not limited to this, and it is needless to say that other publicly known cross-sectional shape capable of exhibiting high frictional resistance can be adopted.

<C> Joint surface between holder and arm 13 The joint surface 147 between the holder 14 and the arm 13 is formed by the holder 14
The outer peripheral side (thin side) 11 is located in the upper part of the above, and the inner peripheral side (thick side) 12 is located in the lower part, which is a substantially triangular shape. On this occasion,
When the bolt 144 is tightened, a uniform fastening force is applied to the holder lower portion 145 and the holder upper portion 146, but of the joint surface 147 of the holder 14 and the arm portion 13, the joint surface 147a on the upper side of the holder 14 reaches the opening 142. Since the length is larger than the length from the lower joint surface 147b of the holder 14 to the opening 142, the holder lower portion 145 and the holder upper portion 14 are
Therefore, the rigidity of the holder upper part 146 becomes relatively larger than that of the holder lower part 145. Therefore, the holder upper opening after fastening becomes narrower than the lower opening. As a result, the holder upper portion 146 is changed to the holder lower portion
A large gripping force can be ensured as compared with No. 5, and the shock absorber 21 gripped thereby has a wedge action to improve the slip-out prevention function.

<D> Operation of Holder With the structure of the holder 14 described above, the frictional resistance obtained by forming a rough surface on the inner peripheral surface of the housing portion 141 of the holder 14 and the housing portion 141 by fastening the bolt 144. The fastening force that reduces the inner diameter and the gripping force of the shock absorber 21, which is obtained from the fastening force, are higher than when the inner peripheral surface of the holder is a smooth surface. Furthermore, the frictional resistance obtained by forming a rough surface on the inner peripheral surface of the housing portion 141 of the holder 14 and the bolt 1
44 In addition to the fastening force due to the inner diameter reduction of the accommodating portion 141 due to the fastening, the wedge action due to the difference in the wall thickness of the joint surface 147 between the holder 14 and the arm portion 13 cooperates to prevent the shock absorber 21 from coming out higher. You can also plan. Although FIG. 3 illustrates an example of using the shock absorber 21 that has been coated, the present invention is not limited to this, and the roughness range described above can be applied to the case where the shock absorber 21 that is not coated is used. Of course. Further, in this embodiment, the joint surface 147 between the arm portion 13 of the fork member 10 and the holder 14 is connected to the holder lower portion 145.
An example in which the wall thickness difference is provided between the holder upper part 146 and the holder upper part 146 is not limited to this, but even when the wall thickness is the same, a high gripping force can be obtained due to the rough surface of the inner peripheral surface of the holder 14 described above. Of course, you can do that.

[0019]

Second Embodiment of the Invention Next, a second embodiment of the present invention will be described. As the projecting cross-sectional shape forming the rough surface in the present embodiment, a saw-tooth shape is used as shown in FIG. 4, instead of the mountain shape described in the first embodiment of the invention.

That is, the cross-section of the projection 148, which is a rough surface formed on the inner peripheral surface of the accommodating portion 141 of the holder 14, has a gentle slope on the opening side of the holder upper portion 146 with respect to the axial direction of the lower end of the shock absorber 21. 148a, lower holder 14
A saw-tooth shape is formed by forming a substantially right-angled inclined surface 148b in the substantially orthogonal direction on the opening side of the fifth opening. As a result, the holder 1
When the lower end portion of the shock absorber 21 is inserted into the accommodating portion 141 of No. 4, the holder upper portion 146 to the holder lower portion 14
Inclined surface 148a of each protrusion 148 for insertion in 5 directions
Since the gentle slope of the blades abuts at a small angle less than a right angle, the saw-tooth shape functions as a guide, and insertion is possible with a relatively low frictional resistance.

On the other hand, in the withdrawal direction of the shock absorber 21 from the holder lower portion 145 toward the holder upper portion 146, a force is applied in the direction of the substantially right-angled slope 148b, and each substantially right-angled slope 147b with respect to the lower end withdrawal direction. Since they abut against each other so as to oppose each other (substantially right angle in this example), they are positioned so as to be caught by the shock absorber 21 to increase the frictional resistance, and prevent the lower end of the shock absorber 21 from pulling out from the accommodating portion 141. .

In the second embodiment of the present invention,
Similar to the first embodiment of the invention, in addition to the frictional resistance obtained by making the cross section of the protrusion 148 forming the rough surface into a sawtooth shape and the fastening force by the inner diameter reduction of the accommodating portion 141 by fastening the bolt 144, Thus, the shock absorber 21 can be prevented from slipping out in cooperation with the wedge action due to the thickness difference of the joint surface 147 between the holder 14 and the arm portion 13.

[0023]

Third Embodiment of the Invention Next, a third embodiment of the present invention will be described. In addition to the first and second embodiments described above, the present embodiment is different from the holder 14 of the shock absorber 21 in this embodiment.
The pitch of the rough surface (the pitch between the protrusions) is unevenly changed between the holder lower side 145 and the holder upper side 146 of the inner peripheral surface. For example, the rough surface pitch of the upper half of the inner peripheral surface of the holder is formed to be relatively larger than the rough surface pitch of the lower half. This provides the following advantages.

That is, the present embodiment is the first embodiment of the invention.
Similarly, when the holder 14 uses the wedge action due to the difference in wall thickness of the joint surface 147 with the arm portion 13, by changing the rough surface pitch with respect to the lower half of the holder inner peripheral surface where the wedge action cannot be expected, By making the frictional resistance larger than the upper half of the inner peripheral surface, the effect of preventing the shock absorber 21 from coming out can be made more remarkable. Specifically, one example is to set the pitch of the rough surface to be smaller (finer) on the lower side than on the upper side. As a result, a high gripping force can be obtained due to the synergistic effect with the wedge action due to the difference in the wall thickness of the holder 14, and the shock absorber 21 can be prevented from slipping out. The above-mentioned pitch may change the size of the rough surface pitch from an arbitrary position on the inner peripheral surface of the holder, or the pitch of the rough surface gradually changes from above to below the inner peripheral surface of the holder to be small (fine). You may do it.

[0025]

Since the present invention has been described above, the following effects can be obtained.

<A> According to the shock absorber supporting fork member of the present invention configured as described above, the inner peripheral surface of the storage portion of the shock absorber is formed to be a rough surface, and the pitch of the rough surface is not uniform. As a result, it becomes possible to obtain a sufficient gripping force without introducing an excessive fastening force for gripping the shock absorber. Therefore, it is not necessary to introduce high tension when fastening the bolt, and the risk of damaging the bolt can be avoided.

<B> According to the shock absorber supporting fork member of the present invention configured as described above, the shock absorber can be sufficiently gripped with the structure normally required for the holder, and Since it is not necessary to introduce high tension when fastening the accommodating portion with the through bolts, it is not necessary to separately impart strength to the entire fork member including the holder, and thus it is possible to realize weight saving and cost reduction by material saving.

<C> According to the shock absorber supporting fork member of the present invention, the friction resistance in the removal direction obtained by the rough surface forming on the inner peripheral surface of the holder accommodating portion and the inner diameter reduction of the accommodating portion by the bolt fastening. And the wedge action due to the difference in wall thickness of the joint surface between the holder and the arm portion cooperate to obtain a higher gripping force and prevent the shock absorber from coming off.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a shock absorber supporting fork member including a holder according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a holder according to the first embodiment of the present invention.

FIG. 3 is a view taken along the line III-III in FIG.

FIG. 4 is a vertical sectional view of a holder according to a second embodiment of the present invention.

FIG. 5 is a perspective view of a conventional suspension device.

[Explanation of symbols]

10 Shock Absorber Supporting Fork Member 11 Outer Side 12 Inner Side 13 Arm 14 Holder 141 Housing 142 Opening 143 Bolt Hole 144 Bolt 145 Lower Holder 146 Holder Upper 147 Joining Surface 147a Upper Joining Surface 147b Lower Joining Surface 148 Projection 148a Sloping surface 148b Substantially right-angled slope 15 Pin connecting member 20 Strut member 21 Shock absorber 22 Spring member 30 Wheel support 40 Lower link member 50 Compression rod 60 Knuckle steering 70 Upper link member

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Fumitaka Saigo             Stock Market Association, 2-18 Kono, Adachi-ku, Tokyo             The company Sannohashi (72) Inventor Wang Shinsei             Stock Market Association, 2-18 Kono, Adachi-ku, Tokyo             The company Sannohashi F-term (reference) 3D001 AA17 AA18 BA03 DA09                 3J069 AA50 CC34 CC38 DD50

Claims (5)

[Claims] 1. A member constituting a suspension device, wherein an arm portion having an arc shape and a cross-section C formed integrally with an upper end of the arm portion and capable of accommodating a lower end of a shock absorber and being clamped by bolt fastening. A shock absorber supporting fork member comprising a V-shaped holder and a pin connecting portion provided at a lower end of the arm portion and having a connecting pin for connecting to a lower link member, wherein the inner peripheral surface of the holder is 3 to 10a. A shock absorber supporting fork member characterized by being formed on a rough surface. 2. The shock absorber supporting fork member according to claim 1, wherein the rough surface in the holder is a groove along the circumferential direction. 3. The shock absorber supporting fork member according to claim 1 or 2, wherein the rough surface has a chevron cross section. 4. The shock absorber supporting fork member according to claim 1 or 2, wherein the rough surface is formed in a direction that gently intersects a holder upper side with a lower end axial direction of the shock absorber housed in the holder. A shock absorber supporting fork member having an inclined surface and having a sawtooth cross section in which the lower side of the holder is a substantially right-angled surface in a substantially orthogonal direction. 5. The shock absorber supporting fork member according to claim 1, wherein the rough surface is formed with a non-uniform pitch.