JP2002070917A - Mounting length limiter for hydraulic shock absorber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically ensure an effective engagement length of a threaded joint part between an outer shell and an extension bracket in a hydraulic shock absorber by means of a mechanical stop means without a visual check through a mark on the effective engagement length of the threaded joint part. SOLUTION: An outer shell 2 with an external thread 5 in the outer circumferential surface has a pin fitting hole 12 cut in the base end circumference, and an extension bracket 6 with an internal thread 14 formed in the inner circumferential surface to leave in the bottom a play portion 13 of a width corresponding to a mounting adjustment length of a hydraulic shock absorber 1 has a pin passing hole 15 cut through the region of the play portion 13. The extension bracket 6 is screwed for retraction onto the outer shell 2 via the external thread 5 and the internal thread 14 to register the pin passing hole 15 in the extension bracket 6 with the pin fitting hole 12 in the outer shell 2. In this state, a stop pin 16 is fitted in the pin fitting hole 12 in the outer shell 2 via the pin passing hole 15 in the extension bracket 6. The abutment of the stop pin 16 and the inner end of the internal thread 14 of the extension bracket 6 holds a design target value of the effective engagement length between the external thread 5 of the outer shell 2 and the internal thread 14 of the extension bracket 6, and at the same time, prevents dislodgment of the extension bracket 6 from the outer shell 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for mounting a hydraulic shock absorber on a predetermined portion of a vehicle or other devices.
A hydraulic shock absorber that can be mounted while being adjusted while adjusting the mounting length of the hydraulic shock absorber over a predetermined range in accordance with the length of the mounting portion of the vehicle or another device (hereinafter simply referred to as a vehicle or the like). The present invention relates to a device for restricting the length of mounting.

[0002]

2. Description of the Related Art Conventionally, as a mounting length adjusting device for a hydraulic shock absorber of this type, a reference mark is provided on an outer peripheral surface of an outer shell forming an outer portion of the hydraulic shock absorber, and an extension bracket is screwed from one end. The outer shell and the extension bracket are relatively rotated with respect to each other using the mark as a guide to restrict the mounting length of the hydraulic shock absorber from becoming too long. The bonding strength is ensured by keeping the values below.

Further, in this case, as a mark to be provided on the outer peripheral surface of the outer shell, a dent is formed on the outer peripheral surface of the male screw portion of the outer shell and paint such as red is applied. Print the color line to be used as a mark on the part, or scrape a part of the male screw and paint the part with red, etc., and use these points and lines as a mark to mark the effective length of the screw joint Is prevented from becoming shorter than the design target value, thereby preventing insufficient strength of the joint.

[0004]

However, according to the above-mentioned mark formed by forming a depression on the outer peripheral surface of the thread portion of the outer shell and applying a paint such as red, the strength of the thread portion for coupling is extremely small. Although it can be applied only by lowering it, it is difficult to confirm the mark because it is difficult to visually confirm.In addition, when a color surrounding the predetermined part of the male screw is printed with the color of the mark, the printed part is peeled. It may be difficult to see or disappear in some cases, and may not be able to serve as a landmark.

[0005] In this regard, in the case where a part of the male screw is cut off and a paint such as red as a mark is applied to the part, the paint does not peel off because the mark does not contact the female screw of the extension bracket. On the other hand, if a part of the male screw is cut off, the male screw on the outer shell side is cut at this part to be discontinuous.

Therefore, there is a possibility that the thread portion serving as the discontinuous end may be deformed and may not be properly engaged with the female screw of the extension bracket. In order to prevent this, the thread of the portion is not deformed. The necessity of performing such a special and troublesome chamfering work arises, and the production is troublesome and the cost is high.

Accordingly, an object of the present invention is to provide a method for automatically connecting a screw coupling portion using mechanical locking means without visually recognizing the effective length of engagement of the screw coupling portion using a passive means such as a mark. It is an object of the present invention to provide a hydraulic shock absorber mounting length limiting device capable of maintaining the engagement effective length of the hydraulic shock absorber at a design strength.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an outer shell having a male screw formed on an outer peripheral surface thereof. An extension bracket with a play portion is screwed in, a pin fitting hole is formed in the outer peripheral portion of the base end of the outer shell, and a pin fitting hole on the outer shell side is formed through the play portion of the extension bracket and relative rotation with the outer shell. And a locking pin is fitted by slightly projecting the head from the pin through hole of the extension bracket into the pin fitting hole of the outer shell, and the locking pin and the inner end of the female screw of the extension bracket are provided. Adjust the hydraulic shock absorber mounting length while restricting the effective length of engagement between the outer shell external thread and the extension bracket internal thread by engaging with the part so that the effective length does not fall below the design strength. Is achieved by way may make.

That is, by forming the hydraulic shock absorber as described above, even if the pin fitting hole of the outer shell is covered with the extension bracket, the outer shell and the extension bracket are relatively rotated to form the pin through hole and the pin through hole. The fitting holes are aligned, and the locking pin can be pushed into the pin fitting hole at the base end of the outer shell through the pin through hole.

[0010] With this configuration, the outer shell and the extension bracket are relatively displaced in the axial direction through the male screw and the female screw by rotating the outer shell and the extension bracket relative to each other. The installation length as the hydraulic shock absorber is adjusted to the shortest state.

On the other hand, the outer shell and the extension bracket are relatively rotated in the opposite directions to be pulled out, and the inner end of the female screw of the extension bracket is brought into contact with a locking pin on the outer shell side, thereby mounting the hydraulic shock absorber. Not only can the length be adjusted to the longest state, but even if a force is applied in the direction in which the outer shell and the extension bracket are further rotated relative to the outer shell from this state, the locking pin fits into the fitting hole of the outer shell. This keeps the state in which the extension bracket is inserted, thereby reliably preventing the extension bracket from slipping out of the outer shell.

When the relative rotation of the outer shell and the extension bracket is stopped when the mounting length of the hydraulic shock absorber reaches an arbitrary length between the shortest state and the longest state, the state at that time is maintained. The hydraulic shock absorber can be adjusted and held at any intermediate mounting length.

Thus, not only is the hydraulic shock absorber in the shortest state in which the inner bottom surface of the extension bracket abuts on the outer surface of the bottom portion of the outer shell, but also the inner end of the female screw of the extension bracket is engaged with the locking pin on the outer shell side. Within the range of the total adjustment length of the hydraulic shock absorber that is stopped by contact, the female screw is prevented from slipping out of the male screw greatly, and the effective length of engagement between the outer shell and the extension bracket is maintained at the design target value. It is possible to prevent the joint strength of the threaded portion from falling below the design target value and causing breakage.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following description of an embodiment of the present invention with reference to the accompanying drawings, a case where the present invention is applied to an upright type hydraulic shock absorber is shown as an example. Needless to say, the present invention can be applied to an inverted hydraulic shock absorber which is conventionally known.

FIG. 1 is an external view showing a hydraulic shock absorber 1 provided with a mounting length adjusting device according to the present invention as viewed from the front, and an outer shell 2 constituting a main body of the hydraulic shock absorber 1 includes: A piston rod 4 having an upper mounting bracket 3 integrally attached to a protruding end thereof upwardly extends and extends.

A male screw 5 is engraved on the outer peripheral surface of the outer shell 2 while leaving both end portions slightly, and an extension bracket 6 is provided to the outer peripheral portion of one end of the outer shell 2 through the male screw 5. Brackets 7 for spring receiving are screwed into the upper part, respectively, and these extension brackets 6 and brackets 7 for spring receiving are firmly fixed by tightening with lock nuts 8, 9 screwed into the male screw 5, respectively. I have to get it.

At the lower end of the extension bracket 6, a lower mounting bracket 10 is fixedly provided in correspondence with the upper mounting bracket 3, and a suspension is provided between the upper mounting bracket 3 and the bracket 7 for spring receiving. A spring 11 is interposed, and the vehicle body is supported by the upper and lower mounting brackets 3 and 10 on the wheels through the suspension spring 11.

FIG. 2 is an enlarged longitudinal sectional front view showing a portion where the extension bracket 6 is attached to the outer shell 2. The outer shell 2 has an outer peripheral surface arranged with male screws 5 and a pin fitting hole 12 at the base end side. In addition, a female screw 14 is formed on the inner peripheral surface of the extension bracket 6 except for a play portion 13 having a width for adjusting and attaching the hydraulic shock absorber 1 to the bottom side. A pin through hole 15 having a diameter larger than that of the pin fitting hole 12 formed in the base end portion on the outer shell 2 side is formed.

In addition, the outer shell 2 and the extension bracket 6 are relatively displaced in the axial direction through the threaded portion of the male screw 5 and the female screw 14 with the relative rotation of the outer shell 2 and the extension bracket 6, so that the outer shell 2 and the extension bracket 6 are bored in the play portion 13 of the extension bracket 6. The pin through hole 15 can be matched with the pin fitting hole 12 on the outer shell 2 side.

As a result, the base end of the locking pin 16 is fitted into the pin fitting hole 12 formed in the base end of the outer shell 2 through the pin through hole 15 of the extension bracket 6, and the locking pin 16 is attached to the extension bracket 6. By contacting the inner end portion of the female screw 14 on the side, the extension bracket 6 is prevented from coming off from the base end portion of the outer shell 2 and dropping off.

Thus, the hydraulic shock absorber 1 of this embodiment
According to this, when the outer shell 2 and the extension bracket 6 are relatively rotated, the outer shell 2 and the extension bracket 6 are relatively displaced in the axial direction through the male screw 5 and the female screw 14, and the pin fitting holes 12 of the outer shell 2 and the extension bracket 6 are provided.
And the pin through hole 15 can be matched.

By pushing the locking pin 16 into the pin fitting hole 12 at the base end of the outer shell 2 through the pin through hole 15, the locking pin is inserted into the pin fitting hole 12 at the base end of the outer shell 2. 16 can be easily attached.

Accordingly, the outer shell 2 and the extension bracket 6 are relatively rotated and extracted, and the inner end of the female screw 14 of the extension bracket 6 is brought into contact with the locking pin 16 on the outer shell 2 side. Even if a force is applied in a direction in which the bracket 6 is relatively rotated and comes out, the locking pin 16 is fixed to the pin fitting hole 1 of the outer shell 2.
Outer shell 2 and extension bracket 6 while fitted in 2
, The hydraulic shock absorber 1 is adjusted to the longest mounting length while preventing the extension bracket 6 from coming out of the outer shell 2.

On the other hand, when the outer shell 2 and the extension bracket 6 are relatively rotated in the opposite directions and operated in a direction of entering each other, the outer bottom surface of the outer shell 2 and the inner bottom surface of the extension bracket 6 come into contact with each other and stop. At this point, the mounting length as the hydraulic shock absorber 1 is adjusted to the shortest state.

When the mounting length of the hydraulic shock absorber 1 reaches an arbitrary length between the shortest and the longest, the outer shell 2
If the relative rotation of the hydraulic shock absorber 1 and the extension bracket 6 is stopped, the hydraulic shock absorber 1 can be adjusted to an arbitrary intermediate mounting length and held while maintaining the state at that time.

In this manner, not only is the hydraulic shock absorber 1 in the shortest state where the inner bottom surface of the extension bracket 6 is stopped against the bottom of the outer shell 2, but also the inner end of the female screw 14 of the extension bracket 6 Within the entire adjustment length of the hydraulic shock absorber 1 which is stopped by contacting the locking pin 16 on the outer shell 2 side, the female screw 14 is prevented from slipping out of the male screw 5 and slipping out. By maintaining the effective engagement length of the threaded portion 6 at the design target value, it is possible to prevent the coupling strength of the threaded portion from being reduced below the design target value and being damaged.

The locking pin 16 fitted to the outer periphery of the base end of the outer shell 2 is
In the case where there is a danger of falling off due to conforming to 5, or danger of dust and dirt entering the pin through hole 15 of the extension bracket 6 and causing harm, etc.
After the locking pin 16 is fitted into the pin fitting hole 12, the pin through hole 15 of the extension bracket 6 is closed with a plug as shown in FIG. What is necessary is just to cover it with a blindfold member 17 such as a seal in place of the stopper.

Further, in the above-described embodiment of the present invention, the case where the installation length limiting device of the hydraulic shock absorber 1 by mechanical means is used alone has been described. It is a matter of course that the mounting length limiting device of the hydraulic shock absorber 1 according to the above may be used in combination with a conventional device which is visually recognized using a mark as a guide.

[0029]

As described above, according to the first aspect of the present invention, a female screw is passed through the outer peripheral portion at the base end of the outer shell having an external thread engraved on the outer peripheral surface, and the bottom portion is adapted to the mounting adjustment length of the hydraulic shock absorber. The extension bracket provided with a play portion having a width to be inserted is screwed, and a pin fitting hole is formed in the outer peripheral portion of the base end of the outer shell. A pin through-hole matching the fitting hole is provided, the head is slightly projected from the pin through-hole of these extension brackets into the pin fitting hole of the outer shell, and the locking pin is fitted. The engagement length with the inner end part regulates the effective length of engagement between the external thread of the outer shell and the internal thread of the extension bracket so that it does not become less than the design strength. By adjusting the length of the outer shell and the extension bracket, regardless of the relative rotation of the outer shell, the meshing effective length of the screw joint between the outer shell and the extension bracket is always maintained at the design target value without lowering the strength of the screw joint. In addition, it is possible to adjust the mounting length of the hydraulic shock absorber in accordance with the length of the mounting portion on the vehicle side while preventing the extension bracket from coming off from the outer shell.

According to the second aspect of the present invention, the base end portion of the locking pin is fitted from outside to the pin fitting hole provided in the outer peripheral portion of the base end on the outer shell through the pin through hole on the extension bracket side. Later, a blind member such as a plug or a seal is provided in the pin through hole of the extension bracket so as to close the pin through hole. In addition to the effect of the invention of the above-mentioned claim 1, the locking pin on the outer shell side is a pin of the extension bracket. It is also possible to eliminate the danger of dropping out of the through-hole or dust or debris entering the inside and causing harm.

[Brief description of the drawings]

FIG. 1 is a partial longitudinal front view showing an embodiment of a hydraulic shock absorber provided with a device for adjusting a length of attachment to a vehicle body according to the present invention.

FIG. 2 is an enlarged longitudinal sectional front view showing only an attachment portion of an extension bracket in the above.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hydraulic shock absorber 2 Outer shell 4 Piston rod 5 Male screw 6 Extension bracket 11 Suspension spring 12 Pin fitting hole 13 Play part 14 Female screw 15 Pin through hole 16 Lock pin 17 Blind member

Claims (2)

[Claims] 1. An extension bracket provided with a play portion having a width suitable for a mounting adjustment length of a hydraulic shock absorber is screwed into a bottom portion of the outer shell through which a female screw is passed through a base end outer peripheral portion of an outer shell having an outer thread engraved on an outer peripheral surface, and A pin insertion hole is formed in the outer peripheral portion of the base end of the outer shell, and a pin through-hole is provided through the play portion of the extension bracket so as to match the pin insertion hole on the outer shell with the relative rotation with the outer shell. The locking pin is fitted by slightly projecting the head from the pin through hole into the pin fitting hole of the outer shell, and the male screw of the outer shell and the extension bracket are engaged by engagement of the locking pin with the inner end portion of the female screw of the extension bracket. A hydraulic shock absorber characterized in that the length of engagement of the hydraulic shock absorber can be adjusted while restricting the effective length of engagement with the female screw to be less than the design strength. A device for limiting the length of the vessel. 2. The base portion of the locking pin is fitted by slightly projecting the head into a pin fitting hole provided in the outer peripheral portion of the base end on the outer shell side through the pin through hole of the extension bracket from the outside,
2. The installation length limiting device for a hydraulic shock absorber according to claim 1, wherein the pin through hole on the extension bracket side is closed with a blind member such as a plug or a seal thereafter.