JP2007147039A - Cylinder device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To firmly fix a steering arm to be connected with a tie rod without emplying welding, in a cylinder device of a hydraulic shock absorber or the like used in a suspension device of a vehicle. <P>SOLUTION: A connected portion 8 formed in a base end portion of a steering arm 5 is fitted onto an outer shell 3 and by bulging a side wall of the outer shell 3, a convex portion of a diameter expanded connected portion 11 is engaged into the serration 10 of the internal circumferential surface of the connected portion 8. The steering arm 5 is fixed in the rolling direction by meshing with the serration 10 and the diameter expanded connected portion 11 and at the same time, the steering arm is fixed in the axial direction by fittings of these concavo-convex portions. By this way, sufficient fixing strength is secured by fixing the steering arm 5 to the base shell 3, without welding, and contaminations generated in welding and deformation problems of the base shell 3 due to heat are eliminated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a cylinder device such as a hydraulic shock absorber attached to a suspension device of a vehicle such as an automobile.

  In general, an automobile suspension device is equipped with a cylindrical hydraulic shock absorber, and a damping force is applied to the vibration and unsprung motion of the vehicle body to improve riding comfort and driving stability. . A suspension strut is one that uses a cylindrical hydraulic shock absorber as a suspension member. The suspension strut is a hydraulic shock absorber, functions as a strength member of the suspension device, is attached with a spring seat that receives the suspension spring, and is attached with a bracket for coupling a knuckle that supports the axle. Furthermore, the suspension strut used in the suspension device for the front wheels (steering wheels) also has a kingpin function, and is rotated by a tie rod of a steering mechanism connected to the arm portion of the knuckle during steering.

Conventionally, a suspension strut has a steering arm to which a tie rod is connected in place of a knuckle arm portion, for example, as described in Patent Document 1, from the viewpoint of mounting in a vehicle and on a vehicle body. Some are welded to the cylinder.
Japanese Utility Model Publication No. 47-3424

  However, when the steering arm is directly welded to the cylinder part, there is a problem of contamination that occurs during welding and deformation of the cylinder part due to heat. Further, since a large torsional load is applied to the steering arm to which the tie rod is connected around the cylinder axis, it is necessary to ensure a sufficient strength to withstand this load.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a cylinder device in which an arm member such as a steering arm is attached to a cylinder portion without welding and a sufficient strength is ensured.

In order to solve the above-mentioned problem, the invention according to claim 1 is a cylinder device in which a rod projects from an end of a cylinder part and an arm member is attached to the cylinder part.
At the base end of the arm member, an annular coupling portion having an uneven portion on the inner periphery is formed, the coupling portion is fitted on the cylinder portion, and the side wall of the cylinder portion is bulged to expand the diameter. The arm member is coupled to the cylinder part by biting into the uneven part.
A cylinder device according to a second aspect of the invention is characterized in that, in the configuration of the first aspect, the uneven portion is a serration.
According to a third aspect of the present invention, in the cylinder device according to the first or second aspect, the side wall of the cylinder portion that is bulged and bites into the concavo-convex portion comprises a plurality of convex portions arranged in parallel in the axial direction. It is an enlarged diameter coupling part.

According to the cylinder device of the first aspect of the present invention, the arm member is coupled to the cylinder portion by the side wall of the bulged cylinder portion biting into the concave and convex portions of the coupling portion, so that the axial direction and the rotational direction around the axis are obtained. Sufficient strength can be obtained.
According to the cylinder device of the second aspect of the invention, the side wall of the bulged cylinder part bites into the serration and the arm member is coupled to the cylinder part.
According to the cylinder device of the third aspect of the present invention, since the plurality of convex portions of the enlarged diameter coupling portion bite into the concave and convex portions of the coupling portion, the coupling strength in the axial direction with respect to the cylinder portion of the arm member by fitting these concave and convex portions. Can be increased.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, a cylinder device 1 according to the present embodiment constitutes a suspension strut that is mounted on a front wheel suspension device of an automobile, and has a cylindrical hydraulic shock absorber body 2 (cylinder) that functions as a suspension member. The spring seat 4 that receives the lower end of a suspension spring (not shown) wound around the hydraulic shock absorber body 2 and the tie rod of the steering device (only the base shell 3 that is a part is shown) A steering arm 5 (arm member) for connecting a not-shown member is attached.

  The hydraulic shock absorber body 2 includes a cylinder portion (only the base shell 3 is shown) in which oil is sealed, a piston (not shown) slidably fitted in the cylinder portion, and one end connected to the piston. And a piston rod (not shown) as a rod whose other end protrudes to the outside of the cylinder part, an oil passage (not shown) through which the oil liquid flows by sliding of the piston, and an oil liquid in the oil passage A damping force generating mechanism (not shown) including an orifice, a disk valve, and the like for controlling the flow of the oil is provided, and the flow of the oil liquid flowing through the oil passage is caused by the damping force generating mechanism with respect to expansion and contraction of the piston rod. By controlling, a damping force is generated.

  The spring seat 4 is formed by bulging a part of the side wall of the base shell 3 to form an enlarged diameter portion 6, and the spring seat 4 is externally fitted to the base shell 3 from above and press-fitted into the enlarged diameter portion 6. The step portion 7 formed on the base portion 6 is attached to the base shell 6 by contacting the end portion of the enlarged diameter portion 6.

  As shown in FIG. 2, the steering arm 5 has a large-diameter annular coupling portion 8 formed at a base end portion attached to the base shell 3, and a small-diameter annular tie rod coupling portion at a distal end portion to which the tie rod is coupled. Is formed. As for the coupling | bond part 8, the serration 10 (uneven | corrugated | grooved part) is formed in the internal peripheral surface. The inner diameter of the coupling portion 8 is slightly larger than the outer diameter of the enlarged diameter portion 6 bulged on the side wall of the base shell 3.

  The coupling portion 8 of the steering arm 5 is fitted on the base shell 3 and positioned at a predetermined position, and then the base shell 3 is bulged to expand the diameter to form the expanded coupling portion 11. It is fixed. As shown in FIG. 4, the enlarged diameter coupling portion 11 has two convex portions 11A arranged in parallel to the axial direction of the base shell 3, and a concave portion 11B is formed between these convex portions 11A. The two convex portions 11 </ b> A bite into the serration 10 of the coupling portion 8. Thereby, the steering arm 5 is fixed in the rotational direction by the engagement of the serration 10 and the enlarged diameter coupling portion 11, and is fixed in the axial direction by fitting these irregularities.

  In this manner, the spring seat 4 and the steering arm 5 can be attached to the base shell 3 without welding, so that sufficient attachment strength can be ensured. The problem of deformation of the base shell 3 due to contamination and heat generated during welding can be solved. Can be resolved.

  Next, a coupling device for coupling the steering arm 5 to the base shell 3 will be described with reference to FIG. As shown in FIG. 6A, the coupling device 12 includes a pressurizing piece 14 having a convex punch portion 13 that is inserted into the base shell 3 and pushes out the two convex portions 11A of the enlarged diameter coupling portion 11. A wedge-shaped mandrel 15 inserted between the pressure pieces 14, a pressure piece holder 16 and a pressure piece guide 17 for supporting the pressure piece 14 so as to be movable in the radial direction in the base shell 3. A return spring 18 for returning the pressure piece 14 and the mandrel 15 to the original position and a positioning jig (not shown) for positioning the steering arm 5 fitted on the base shell 3 at a predetermined position are provided. . In addition, when the rigidity of the coupling portion 8 of the steering arm 5 is low, a restraining jig for restraining the outer peripheral portion of the coupling portion 8 may be provided in order to prevent deformation (expansion) of the coupling portion 8 during pressurization. .

  Then, as shown in FIG. 6B, the steering arm 5 is positioned by a positioning jig, a mandrel 15 is inserted between the pressure pieces 14, and the pressure piece 14 is moved radially outward and expanded. Then, the punched portion 13 shears and deforms the side wall of the base shell 3 into the serration 10 of the coupling portion 8 of the steering arm 5 to form the enlarged diameter coupling portion 11 having the convex portion 11A and the concave portion 11B. After forming the enlarged diameter coupling portion 11, the mandrel 15 and the pressure piece 14 are moved backward by the return spring 18. In this way, the steering arm 5 can be coupled to the base shell 3.

  At this time, the serration 10 of the coupling portion 8 of the steering arm 5 is formed by broaching, press molding, or the like, but the tip of the tooth of the serration 10 is sharpened, and the convex portion of the diameter expansion coupling portion 11 on the base shell 3 side is convex. It is preferable that the portion 11A is easy to eat. Further, by making the hardness of the steering arm 5 slightly harder than that of the base shell 3, a good coupling state can be obtained between the serration 10 and the convex portions 11A and the concave portions 11B of the enlarged diameter coupling portion 11. 3 and the steering arm 5 can be enhanced in the axial direction and in the rotational direction around the axis.

  Next, the process of attaching the spring seat 4 and the steering arm 5 to the base shell 3 will be described with reference to FIG. As shown in FIG. 7A, the side wall of the base shell 3 is bulged to form the enlarged diameter portion 6 into which the spring seat 6 is press-fitted. As shown in FIG. 7B, the coupling portion 8 of the steering arm 5 is fitted on the base shell 3 and positioned by a jig (not shown). As shown in FIG. 7C, the coupling device 12 bulges the side wall of the base shell 3 to form the enlarged diameter coupling portion 11, and couples the steering arm 5 to the base shell 3. Then, as shown in FIG. 7D, the spring seat 4 is press-fitted into the enlarged diameter portion 6 of the base shell 3. In this way, the spring seat 4 and the steering arm 5 can be attached to the base shell 3 without welding.

  In the above embodiment, as shown in FIG. 3, the axial mounting strength of the steering arm 5 can be increased by forming the inner peripheral groove 19 in the serration 10 of the coupling portion 8 of the steering arm 5. Further, as shown in FIG. 5, the steering arm 5 can be coupled to the base shell 3 by forming one convex portion 11 </ b> A in the enlarged diameter coupling portion 11 and biting it into the serration 10, or Three or more (plural) convex portions 11 </ b> A may be eaten into the serration 10. Also. The coupling portion 8 may be provided with other uneven shapes instead of the serration 10.

  In the above-described embodiment, the case where a hydraulic shock absorber is used as the cylinder device has been described. However, the present invention is not limited to this, and is similarly applied to a cylinder device having another structure such as a hydraulic cylinder of an active suspension. be able to.

It is a longitudinal cross-sectional view of the principal part of the cylinder apparatus which concerns on one Embodiment of this invention. It is a longitudinal cross-sectional view of the steering arm used for the cylinder apparatus shown in FIG. It is a longitudinal cross-sectional view of the modification of the steering arm used for the cylinder apparatus shown in FIG. It is a longitudinal cross-sectional view which expands and shows the coupling | bond part of the base shell and steering arm of the cylinder apparatus shown in FIG. It is a longitudinal cross-sectional view which expands and shows the modification of the coupling | bond part of the base shell and steering arm of the cylinder apparatus shown in FIG. It is a longitudinal cross-sectional view of the principal part of the coupling device for couple | bonding a steering arm with the base shell of the cylinder apparatus shown in FIG. It is a figure which shows the process of attaching a spring seat and a steering arm to the base shell of the cylinder apparatus shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cylinder apparatus, 3 Base shell (cylinder part), 5 Steering arm (arm member), 8 coupling | bond part, 10 Serration (uneven | corrugated part), 11 Large diameter coupling | bond part, 11A Convex part, 11B Concave part

Claims (3)

In the cylinder device in which the rod protrudes from the end of the cylinder part and the arm member is attached to the cylinder part,
At the base end of the arm member, an annular coupling portion having an uneven portion on the inner periphery is formed, the coupling portion is fitted on the cylinder portion, and the side wall of the cylinder portion is bulged to expand the diameter. A cylinder device characterized in that the arm member is coupled to the cylinder part by biting into the uneven part. The cylinder device according to claim 1, wherein the uneven portion is a serration. 3. The cylinder device according to claim 1, wherein a side wall of the cylinder portion that bulges and bites into the concavo-convex portion is a diameter expansion coupling portion including a plurality of convex portions arranged in parallel in the axial direction. .

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