JP2005036887A - Strut type shock absorber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a strut type shock absorber with a spring seat structure, easily applicable to the specifications of a suspension spring, different only in coil diameter or length, in a production line. <P>SOLUTION: The strut type shock absorber comprises a bottomed cylindrical cylinder body 21, a free piston 22 reciprocatingly inserted in the cylinder body 21 for separating the cylinder body 21 into a high pressure gas chamber G and an oil chamber O, a rod body 23 to be moved in and out of the cylinder body 21, a piston body 28 connected to the base end of the rod body 23 for separating the oil chamber O of the cylinder body 21 into a rod side chamber 26 and an anti rod side chamber 27, and a spring seat 35 attached to the outer periphery of the cylinder body 21 for supporting the suspension spring 44. A bottomed cylindrical protector 34 with a mounting member 38 on a bottom 37 is mounted on the lower outer periphery of the cylinder body 21, and the spring seat 35 is attached to the protector 34. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a strut type shock absorber used for a suspension device of a vehicle such as an automobile.

  Conventionally, as this type of strut type shock absorber, the one shown in Patent Document 1 can be exemplified.

  The strut-type shock absorber includes a bottomed cylindrical base portion including an insertion portion into which one end side of the outer cylinder is inserted and a sealing portion that seals one end side of the outer cylinder, and a spring receiver integrally formed on the outer periphery of the base portion. A bottomed cylindrical shape in which hydraulic oil is enclosed by inserting one end side of the outer cylinder into the insertion part and sealing one end side of the outer cylinder with the sealing part together with the insertion The cylinder body is formed.

In this case, the bottom plate or the like that is a component for sealing one end side of the outer cylinder can be omitted, so that the number of components can be reduced and the manufacturing cost can be reduced.
JP-A-10-103398 (FIGS. 1 and 2)

  However, the strut type shock absorber configured as described above has the following problems in the structure of the spring seat.

  That is, since the spring receiving portion that supports the suspension spring is formed integrally with the sealing portion and the insertion portion that seal the outer cylinder, for example, struts having specifications that differ only in the coil diameter and length of the spring. When manufacturing a type shock absorber, it is necessary to newly design an entire spring seat including an insertion portion and a sealing portion for sealing one end side of the outer cylinder.

  In particular, when the length of the suspension spring is different, the relative position of the spring receiving part with respect to the outer cylinder is different, so if the shape of the spring receiving part cannot be changed, the welded part between the outer cylinder and the spring seat is changed. Therefore, it is necessary to adjust the welding position, time, etc. in the production line, and accordingly, there is a problem that an extra setup time is required and the production cost increases.

  Accordingly, an object of the present invention is to provide a strut-type shock absorber having a spring seat structure that can easily cope with specifications that differ only in the coil diameter and length of the suspension spring in its production line. .

  In order to achieve the above object, the present invention provides a cylinder body having a bottomed cylindrical shape, and a free piston that is removably inserted into the cylinder body and separates the cylinder body into a high-pressure gas chamber and an oil chamber. A rod body protruding from the cylinder body, a piston body connected to the base end of the rod body and separating the oil chamber in the cylinder body into a rod side chamber and an anti-rod side chamber, and a suspension spring attached to the outer periphery of the cylinder body A strut-type shock absorber having a spring seat for supporting the cylinder body is mounted with a bottomed cylindrical protective member having a mounting member at the bottom on the lower outer periphery of the cylinder body, and the spring seat is attached to the protective member It is characterized by having attached.

  In this case, it is preferable to attach the spring seat to the protection member by providing a small diameter portion on the outer periphery of the opening end of the protection member and press-fitting a narrow portion provided in the attachment portion of the spring seat into the small diameter portion.

  Further, a notch hole may be provided in the bottom of the protective member, and the bottom of the cylinder body and the bottom of the protective member may be welded and fixed through the notch.

  The present invention has the following effects.

  1) According to the invention of claim 1, since the protective member is mounted on the lower outer periphery of the cylinder body, and the spring seat is attached to the protective member, the strut type having specifications that differ only in the coil diameter and length of the suspension spring. When the shock absorber is to be manufactured, it is only necessary to design a spring seat having a different shape of the seat portion supporting the suspension spring in advance and attach it to the protective member.

  Accordingly, as shown in the conventional example, the entire spring seat including the insertion portion and the sealing portion for sealing one end side of the outer cylinder is newly designed, or the welding portion between the outer cylinder and the spring seat is changed. Therefore, in the production line, it is possible to easily cope with omitting that the readjustment of the welding position, time, etc. is performed.

  2) According to the invention of claim 2, the spring seat is attached to the protection member by press-fitting the throttle portion provided in the attachment portion of the spring seat into the small diameter portion provided at the opening end of the protection member. Both can be easily and inexpensively attached without special processing such as the above.

  3) According to the invention of claim 3, since the notch hole is provided in the bottom of the protection member and the protection member and the cylinder body are fixed by welding through the notch hole, both can be reliably fixed. In addition, it is possible to reliably prevent the influence of heat during welding from reaching the peripheral surface of the cylinder body where the piston body and the free piston move.

  Hereinafter, an embodiment in which the present invention is embodied in a single-cylinder strut type shock absorber used in a suspension device for an automobile will be described with reference to the drawings.

  As shown in FIG. 1, the strut type shock absorber includes a cylinder body 21 having a bottomed cylindrical shape, and is inserted into the cylinder body 21 so as to be reciprocally movable. A piston body that is coupled to a free piston 22 that separates into a chamber O and a base end of a rod body 23 that protrudes and retracts from the cylinder body 21 and separates the oil chamber O in the cylinder body 21 into a rod side chamber 26 and an anti-rod side chamber 27. 28, a protector 34 as a protection member of the present invention mounted on the outer periphery of the bottom of the cylinder body 21, and a spring seat 35 attached to the protector 34.

  More specifically, the piston body 28 is fixed to the rod body 23 by a nut 29, and a pressure side valve 31 for closing a pressure side port (not shown) so as to be openable and closable is provided on the side surface of the rod side chamber 26 of the piston body 28. An extension side valve 33 that closes the extension side port 32 so as to be openable and closable is provided on the side surface of the piston body 28 opposite to the rod side chamber 27.

  Further, the bottom 24 of the cylinder body 21 is formed by closing a pipe material, and the whole is formed in a substantially conical shape.

The protector 34 includes a cylindrical main body 36 having an inner diameter substantially the same as the outer diameter of the cylinder body 21, a bottom portion 37 formed in substantially the same shape as the conical bottom portion 24 of the cylinder body 21, and the bottom portion 37. It is comprised from the attachment eye 38 as an attachment member fixed by welding to.
As shown in FIG. 2, four notch holes 39 are formed in the bottom portion to which the mounting eye 38 is fixed by welding, and a welding device (not shown) is inserted into the notch hole 39 so that the bottom portions 24 and 37 of each other are inserted. The protector 34 and the cylinder body 21 are fixed by welding S to each other.

  A small-diameter portion 41 is formed at the open end of the main body 36 (referring to the upper portion in FIG. 1), and a step portion 42 is provided at the boundary between the small-diameter portion 41 and the lower large-diameter portion.

  The spring seat 35 includes a cylindrical attachment portion 43 and a seat portion 45 for supporting the suspension spring 44 extending outward from the lower portion of the attachment portion 43, and is provided on the upper portion of the attachment portion 43. The cylindrical throttle portion 46 is press-fitted into the small-diameter portion 41 of the protector 34 from above, and the both steps are fixedly attached by the step portion 42.

  The strut-type shock absorber configured as described above connects the mounting eye 38 to the lower spring side of the vehicle body, connects the tip of the rod body 23 to the upper spring side of the vehicle body, and connects the upper spring side of the vehicle body and the spring seat 35. A suspension device is configured by disposing a suspension spring 44 between the seat portion 45.

  When the rod body 23 is retracted from the cylinder body 21 in the suspension operating state, the pressurized hydraulic oil in the rod side chamber 26 pushes and opens the extension side valve 33 via the extension side port 32. Simultaneously with the flow to the rod side chamber 27 side, an extension side damping force is generated. Further, during the contraction stroke in which the rod body 23 enters the cylinder body 21, the pressurized hydraulic oil in the non-rod side chamber 27 pushes and opens the pressure side valve 31 via the pressure side port, and simultaneously flows into the rod side 26 chamber. Generates a damping force.

  Here, according to the present embodiment, since the protector 34 is attached to the lower outer periphery of the strut type shock absorber, the cylinder body 21 is prevented from being damaged or dented by a stepping stone or the like generated in the use state of the suspension. can do.

  This is a very effective effect in the present invention that uses a single cylinder type shock absorber in which the piston 22 and the free piston 22 are slidably arranged inside the cylinder body 21.

  Further, as a structure for attaching the spring seat 35 to the protector 34, the throttle portion 46 provided on the attachment portion 43 of the spring seat 35 is press-fitted into the small diameter portion 41 provided on the main body 36 of the protector 34, and provided on the main body 36 side. Since both of the step portions 42 are fixedly attached to each other, the spring seat 35 can be attached to the protector 34 without performing special processing such as welding.

  In particular, when a strut-type shock absorber having specifications that differ only in the coil diameter and length of the spring 44 is to be manufactured, a spring seat 35 having a different shape of the seat portion 45 is designed in advance and press-fitted into the protector 34. Just good.

  Accordingly, as shown in the conventional example, the entire spring seat including the insertion portion and the sealing portion for sealing one end side of the outer cylinder is newly designed, or the welded portion between the cylinder body 21 and the spring seat 35 is formed. Since it can be omitted in the production line that the readjustment of the welding position, time, etc. is performed in the production line, it can be produced easily and inexpensively.

  In addition, since the notch hole 39 is provided in the bottom 37 of the protector 34 and the protector 34 and the cylinder body 21 are fixed by welding through the notch hole 39, not only can the both be securely fixed, but also welding. It is possible to reliably prevent the influence of the heat from reaching the inner peripheral surface of the cylinder body 21 where the piston body 28 and the free piston 22 move.

  In addition, this invention is not limited to the said embodiment, For example, it can also be changed and actualized as follows.

  1) For the attachment structure of the spring seat 35 to the protector 34, serration coupling, welding, or the like can be used in addition to the press-fitting of the present embodiment.

  2) Although the protector 34 has a cylindrical shape in the present embodiment, a cutout window or the like may be provided in a portion where there is no concern about a stepping stone or the like to reduce the material cost or reduce the weight of the product itself.

1 is a partially longitudinal front view of a strut type shock absorber showing an embodiment of the present invention. It is a bottom view which shows the bottom part of a protection member.

Explanation of symbols

21 Cylinder body 22 Free piston 23 Rod body 26 Rod side chamber 27 Anti-rod side chamber 28 Piston body 34 Protector (protective member)
35 Spring seat 37 Bottom 38 Mounting eye (Mounting member)
39 Notch hole 41 Small diameter part 42 Step part 43 Mounting part 44 Suspension spring 46 Restriction part G High pressure gas chamber O Oil chamber

Claims (3)

A cylinder body having a bottomed cylindrical shape, a free piston which is removably inserted into the cylinder body and separates the cylinder body into a high-pressure gas chamber and an oil chamber, a rod body which protrudes and retracts from the cylinder body, and a rod A strut type shock comprising a piston body connected to the base end of the body and separating the oil chamber in the cylinder body into a rod side chamber and an anti-rod side chamber, and a spring seat attached to the outer periphery of the cylinder body and supporting a suspension spring In the absorber, a strut type shock absorber, wherein a bottomed cylindrical protective member having a mounting member at the bottom is attached to the lower outer periphery of the cylinder body, and the spring seat is attached to the protective member. . 2. A strut according to claim 1, wherein a small-diameter portion is provided on the outer periphery of the opening end of the protective member, and the spring seat is attached to the protective member by press-fitting a throttle portion provided in the attachment portion of the spring seat into the small-diameter portion. Type shock absorber. The strut type shock absorber according to claim 1, wherein a notch hole is provided in a bottom portion of the protection member, and the bottom portion of the cylinder body and the bottom portion of the protection member are welded and fixed through the notch hole.

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