JP2017155829A - Bound stopper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bound stopper having a new structure capable of effectively preventing a falling of a dust cover while suppressing influence against stopper characteristics.SOLUTION: This invention relates to a bound stopper 10 which has a cylindrical main body part 14 and to which a dust cover 12 is fixed. The cylindrical main body part 14 is integrally formed with a base part 24 protruding toward its outer periphery, the base part 24 is integrally formed with a connecting part 26 protruding in an axial direction. An annular fixing member 34 having a larger deformation rigidity than that of the cylindrical main body part 14 is fixed to the connecting part 26. An axial end part of the dust cover 12 is fixed to the fixing member 34. The fixing member 34 is arranged outside in an axial direction with respect to the cylindrical main body part 14 and at the same time the fixing member 34 is arranged at an outer peripheral side rather than an inner peripheral end of the base part 24.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a bound stopper that limits the amount of contraction and deformation of a shock absorber that constitutes an automobile suspension or the like.

  2. Description of the Related Art Conventionally, bound stoppers that limit the amount of contraction and deformation of a shock absorber that constitutes an automobile suspension or the like are known. The bounce stopper is a cylinder that is externally attached to the piston rod of the shock absorber, as in the bumper bar disclosed in Japanese Utility Model Laid-Open No. 3-4939 (Patent Document 1). Is in contact with the cylinder of the shock absorber and compressed in the axial direction between the piston rod and the cylinder, so that the amount of contraction of the shock absorber is limited in a buffering manner.

  By the way, a dust cover surrounding the outer peripheral side of the shock absorber may be provided so as to prevent foreign matters from adhering to the sliding portion of the shock absorber. This dust cover may be integrally formed with the bound stopper, but when the dust cover is formed of resin or the like, the bound stopper and the dust cover are made of different materials. A separate dust cover is attached to the bound stopper in an extrapolated state.

  However, in the structure where a separate dust cover is attached to the bound stopper, when the shrinkage amount of the shock absorber is limited by the bound stopper, the dust cover attached to the outer peripheral surface of the bound stopper is not elastically deformed. May drop off from the bound stopper.

  Therefore, in Patent Document 1, a hard part having high rigidity is provided at the end of the bumper bar, and the dust cover is attached to the hard part, thereby preventing the dust cover from falling off the bumper bar when the bumper bar is deformed. ing.

  However, if the hard part is directly fixed to the bumper bar as in Patent Document 1, the amount of elastic deformation at the end of the bumper bar is limited by the hard part, which may affect the stopper characteristics of the bumper bar. .

Japanese Utility Model Publication No. 3-4939

  The present invention has been made in the background of the above-mentioned circumstances, and its solution problem is a bounce of a novel structure that can effectively prevent the dust cover from falling off while suppressing the influence on the stopper characteristics. It is to provide a stopper.

  Hereinafter, the aspect of this invention made | formed in order to solve such a subject is described. In addition, the component employ | adopted in each aspect as described below is employable by arbitrary combinations as much as possible.

  That is, the first aspect of the present invention includes a cylindrical main body portion that is extrapolated to the piston rod of the shock absorber and elastically limits the amount of contraction deformation of the shock absorber, and the sliding of the shock absorber. A separate dust cover that covers a portion is a bound stopper that is attached to the cylindrical main body, and a base that protrudes to the outer periphery is integrally formed on the cylindrical main body, and the base A connecting portion that protrudes in the axial direction is integrally formed with an annular mounting member having a deformation rigidity larger than that of the cylindrical main body portion, and the axial end of the dust cover is fixed to the connecting portion. The mounting member is attached to the mounting member, and the mounting member is disposed on the axially outer side with respect to the cylindrical main body portion, and the mounting member is located on the inner peripheral end of the base portion. Outer peripheral side That are arranged, it characterized.

  According to the bound stopper having the structure according to the first aspect of the present invention, the dust cover is attached to the attachment member having a deformation rigidity larger than that of the cylindrical main body portion, so that the dust cover is elastically deformed by the cylindrical main body portion. Dropout can be prevented.

  In addition, since the mounting member is disposed on the outer side in the axial direction with respect to the cylindrical main body portion and is disposed on the outer peripheral side with respect to the inner peripheral end of the base portion, the elastic deformation of the cylindrical main body portion is limited by the mounting member. It is hard to be done. Therefore, a buffering stopper action due to the low spring characteristic of the cylindrical main body is realized, and, for example, when applied to a shock absorber constituting a suspension mechanism of a vehicle, the ride comfort is improved.

  According to a second aspect of the present invention, in the bound stopper having the structure according to the first aspect, the axial minimum thickness dimension of the base portion is smaller than the radial minimum thickness dimension of the cylindrical main body portion. Is.

  According to the second aspect, since the base is thinner than the cylindrical main body, it is difficult for the base to hinder the elastic deformation of the cylindrical main body, and the cylindrical main body due to the provision of the base High spring is avoided.

  According to a third aspect of the present invention, in the bound stopper having the structure according to the first or second aspect, the base portion is provided to project from the axial end portion of the cylindrical main body portion to the outer periphery. .

  According to the 3rd aspect, an attachment member can be arrange | positioned at an axial direction outer side with respect to a cylindrical main-body part with a short connection part.

  According to a fourth aspect of the present invention, in the bound stopper having a structure according to any one of the first to third aspects, the connecting portion is provided so as to protrude in the axial direction from the outer peripheral end portion of the base portion. It is.

  According to the 4th aspect, the attachment member of the magnitude | size corresponding to a dust cover can be fixed to a connection part, without making a base part remarkably long. Further, by preventing the base portion from protruding further to the outer periphery than the connecting portion, the space required on the outer peripheral side than the connecting portion can be reduced.

  According to a fifth aspect of the present invention, in the bound stopper having a structure according to any one of the first to fourth aspects, a hook-like protrusion that covers an axial end portion of the dust cover attached to the cylindrical main body portion. The part is provided so as to protrude from one of the base part and the connecting part to the outer periphery.

  According to the fifth aspect, since the end opening of the cylindrical dust cover is covered with the hook-shaped protrusion, it becomes difficult for foreign matters such as water to enter the inner periphery of the dust cover. The durability of the connecting portion of the cover and the shock absorber can be improved.

  According to a sixth aspect of the present invention, in the bound stopper having the structure according to any one of the first to fifth aspects, a cylindrical fixing portion to which the attachment member is fixed to the connecting portion and the fixing portion. The dust cover is integrally provided with a locking portion that protrudes in a direction perpendicular to the axis and that locks the dust cover in the axial direction.

  According to the sixth aspect, the mounting member can be firmly fixed to the connecting portion with a large fixing area. Further, the amount of elastic deformation of the connecting portion is limited by the fixing portion, so that the dust cover is stably held at a predetermined position with respect to the bound stopper.

  According to the present invention, the cylindrical main body in which the base projecting outward from the cylindrical main body and the coupling projecting in the axial direction from the base are integrally formed on the cylindrical main body and fixed to the coupling. Since the dust cover is attached to the attachment member having a larger deformation rigidity than the portion, the dust cover is prevented from falling off due to the elastic deformation of the cylindrical main body portion. Furthermore, since the mounting member is disposed on the axially outer side with respect to the cylindrical main body portion and the mounting member is disposed on the outer peripheral side with respect to the inner peripheral end of the base portion, elastic deformation of the cylindrical main body portion is caused. It is difficult to be limited by the mounting member, and a buffering stopper action due to the low spring characteristic of the cylindrical main body is realized.

The longitudinal cross-sectional view which shows the bound stopper as 1st embodiment of this invention in the mounting state of a dust cover. The fragmentary longitudinal cross-section which expands and shows the A section of the bound stopper shown in FIG. The longitudinal cross-sectional view which shows the bound stopper shown in FIG. 1 in the mounting state to a vehicle. The longitudinal cross-sectional view which shows the bound stopper as 2nd embodiment of this invention in the mounting state of a dust cover.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a bound stopper 10 as a first embodiment of the present invention with a dust cover 12 attached thereto. In the following description, the vertical direction refers to the vertical direction in FIG. 1 that is the axial direction of the bound stopper 10.

  More specifically, the bound stopper 10 includes a cylindrical main body portion 14. The cylindrical main body portion 14 is formed of a rubber elastic body having a substantially cylindrical shape as a whole, and a plurality of annular concave grooves 16 that open to the outer peripheral surface and extend in the circumferential direction have a predetermined distance from each other in the axial direction. It is formed apart. As a result, the outer peripheral surface of the cylindrical main body portion 14 is partially reduced in diameter at the portion where the annular groove 16 is formed, and is constricted at each portion where the annular groove 16 is formed. Moreover, since the inner peripheral surface of the cylindrical main body portion 14 is a substantially cylindrical surface, the portion where the annular groove 16 is formed in the cylindrical main body portion 14 is thinner than the other portions, and the cylindrical main body 14 The portion 14 is provided with thick portions and thin portions alternately in the axial direction. In the present embodiment, the three annular grooves 16, 16, 16 are provided apart from each other in the axial direction, and there are four between the axial ends of the cylindrical body 14 and the axial direction of the annular groove 16. There are two thick sections. In addition, the inner peripheral surface of the cylindrical main body portion 14 is slightly enlarged in diameter at a thick portion where the annular groove 16 is removed in the axial direction, and the cylindrical main body portion 14 has a bellows structure as a whole.

  Further, the cylindrical main body portion 14 is integrally formed with a buffer protrusion 18 that protrudes further downward from the lower surface in the axial direction. In the present embodiment, the buffer protrusions 18 are substantially hemispherical, and are provided at a plurality of locations in the circumferential direction of the cylindrical main body 14. When the shock absorber 62, which will be described later, contracts, the cylindrical main body 72 is retracted. It comes into contact with the part 14 before the part 14.

  Further, a restraining member 20 is attached to the thick portion of the cylindrical main body portion 14 located between the annular grooves 16. The restraining member 20 has a substantially annular shape, is made of a metal or a hard synthetic resin, and has a deformation rigidity larger than that of the cylindrical main body portion 14. The restraining member 20 is fixed to the outer peripheral end of the thick portion of the cylindrical main body 14, and the amount of elastic deformation to the outer peripheral side of the cylindrical main body 14 is limited by the restraining member 20. The restraining member 20 is appropriately provided according to the required stopper characteristics, durability, and the like, and is omitted in the case where a plurality of restraining members 20 are provided, or cases where different shapes and sizes are adopted. Sometimes it is done.

  Further, as shown in FIGS. 1 and 2, a cover attaching portion 22 is integrally formed at the lower end portion of the cylindrical main body portion 14. The cover attaching part 22 is integrally provided with a base part 24 projecting from the cylindrical main body part 14 to the outer periphery and a connecting part 26 projecting from the base part 24 in the axial direction.

The base 24 is provided so as to protrude from the axial end of the cylindrical main body 14 to the outer periphery, is continuously provided with a substantially constant cross-sectional shape over the entire periphery, and opens to the lower surface to surround the base 24. A groove-shaped thinned portion 28 is formed extending continuously in the direction over the entire circumference. Since the base portion 24 of the present embodiment is thinned in the axial direction by the groove-shaped thinned portion 28, the minimum thickness dimension (t ₁ ) in the axial direction is the minimum thickness in the radial direction of the cylindrical main body portion 14. It is smaller than the dimension (T), and the deformation rigidity of the base portion 24 is smaller than that of the cylindrical main body portion 14. Furthermore, the upper surface of the base portion 24 is inclined downward toward the outer periphery, so that rainwater or the like flows to the outer periphery and does not easily stay on the base portion 24. Furthermore, a flange-like protruding portion 32 that protrudes toward the outer peripheral side is integrally formed at the outer peripheral end portion of the base portion 24. The hook-like protruding portion 32 has a protruding dimension that reaches the outer periphery further than the outer peripheral surface of the upper end of a dust cover 12 (described later) that is extrapolated to the connecting portion 26, and the upper surface is inclined downward toward the outer periphery.

The connecting portion 26 has a substantially cylindrical shape as a whole, and is provided so as to protrude downward in the axial direction from the outer peripheral end portion of the base portion 24. The connecting portion 26 of the present embodiment has a minimum radial dimension (t ₂ ) that is smaller than the minimum radial dimension (T) of the cylindrical main body 14, and deformation of the connecting part 26. The rigidity is smaller than that of the cylindrical main body 14. In addition, a plurality of air vent grooves 30 extending in the radial direction are formed at the lower end portion of the connecting portion 26, and a texture is formed on the lower surface of the connecting portion 26.

  An attachment member 34 is fixed to the connecting portion 26. The attachment member 34 is made of metal, hard synthetic resin, or the like, and is harder and has a greater deformation rigidity than the cylindrical main body 14. The mounting member 34 of the present embodiment is an annular member that is continuous over the entire circumference with a substantially constant L-shaped cross section as a whole, and includes a substantially cylindrical fixing portion 36 that extends in the axial direction, and a fixing portion 36. A substantially annular locking portion 38 that protrudes from the lower end portion in the direction perpendicular to the axis over the entire circumference is integrally provided. In the present embodiment, a press fitting obtained by pressing a metal plate material is employed as the attachment member 34.

  The attachment member 34 is fixed to the connecting portion 26. That is, the inner peripheral surface of the fixing portion 36 of the attachment member 34 is fixed to the outer peripheral surface of the intermediate portion in the axial direction of the connecting portion 26, and the lower end portion of the connecting portion 26 is disposed on the lower surface of the locking portion 38 of the mounting member 34. Is fixed. Further, in the attachment member 34, the outer peripheral surface of the fixing portion 36 and the upper surface of the locking portion 38 are exposed from the connecting portion 26. In the present embodiment, since the attachment member 34 has an L-shaped cross section that integrally includes the locking portion 38 and the fixing portion 36, the attachment member 34 is firmly fixed to the connecting portion 26 with a large fixing area. The edge of the inner peripheral end of the stop portion 38 does not come into contact with the connecting portion 26, and the connecting portion 26 is not easily cracked due to the mounting member 34. In particular, in the present embodiment, the attachment member 34 is a press fitting, and the locking portion 38 and the fixing portion 36 are integrally formed by bending, so that a continuous portion of the locking portion 38 and the fixing portion 36 is formed. There is no corner, and damage to the connecting portion 26 due to contact with the corner is less likely to occur.

  A dust cover 12 is attached to the bound stopper 10. The dust cover 12 has a thin cylindrical shape as a whole, and is made of resin in this embodiment. As a material for forming the dust cover 12, for example, a material obtained by mixing and dispersing ethylene / propylene rubber (EPDM) in polypropylene (PP), which is a thermoplastic resin, is preferable because of excellent weather resistance, moldability, and the like. Adopted. However, when the thermoplastic resin is formed, for example, polyolefin resins such as polypropylene and polyethylene, polyamide resins, polyvinyl chloride resins, polyester resins, urethane resins, styrene resins, olefin resins, etc. Can also be employed. Moreover, as a molding method of the dust cover 12, blow molding is preferably employed, but injection molding can also be employed.

  Furthermore, the dust cover 12 includes a bellows portion 40. The bellows portion 40 has a structure in which a plurality of convex crest portions 42 are continuously formed integrally in the axial direction toward the outer periphery. The peak portion 42 includes a pair of inclined wall portions 44 and 44 that are tapered toward the outer side in the axial direction toward the inner periphery, and is a substantially rollover V-shape that protrudes toward the outer periphery. The cross section is continuously annular over the entire circumference. In addition, the bellows part 40 of this embodiment becomes thin gradually as it goes to an outer periphery, The difference of this thickness is implement | achieved by the blow molding of the dust cover 12. FIG.

  Furthermore, a small valley portion 46 that opens toward the outer periphery is formed at the outer peripheral end of the peak portion 42. The small valley portion 46 is formed on the outer peripheral portion of the bellows portion 40, and has a substantially roll-over V-shaped cross section that protrudes toward the inner periphery and expands toward the outer periphery, and is continuously formed over the entire periphery. Note that the small valley portion 46 is narrower and shallower than the valley portion formed between the mountain portions 42 and 42 adjacent in the axial direction.

  Further, an upper mounting portion 48 is integrally formed with the bellows portion 40 above the bellows portion 40 in the axial direction. The upper mounting portion 48 has a substantially cylindrical shape as a whole, and a locking protrusion 50 that protrudes toward the inner periphery is formed at an axially intermediate portion. The locking projection 50 is formed with a substantially constant thickness by projecting to the inner periphery and being recessed in the shape of a groove on the outer periphery, and the upper mounting portion 48 is partially formed by the portion where the locking projection 50 is formed. It has a small diameter. Further, the locking protrusion 50 of the present embodiment includes a retaining portion 52 that extends in a direction substantially perpendicular to the axis toward the inner peripheral side, and an insertion guide portion 54 that extends while tilting outward from the inner peripheral end of the retaining portion 52 to the outer periphery. It has. Note that an upper end portion of the upper mounting portion 48 having a substantially cylindrical shape and extending in the axial direction is formed integrally with the insertion guide portion 54 and extends upward in the axial direction from the upper end of the insertion guide portion 54.

  Furthermore, a lower attachment portion 56 is integrally formed with the bellows portion 40 below the bellows portion 40 in the axial direction. The lower mounting portion 56 has a substantially cylindrical shape as a whole, and includes a peripheral groove 58 that opens to the inner peripheral surface in an intermediate portion in the axial direction. Furthermore, enlarged diameter portions 60 are formed at a plurality of locations in the circumferential direction of the lower mounting portion 56. The enlarged-diameter portion 60 protrudes toward the outer periphery, and extends substantially linearly in the axial direction with a cross-sectional shape that expands in the circumferential direction as it goes to the inner periphery. The enlarged diameter portions 60 of the present embodiment are arranged radially at substantially equal intervals in the circumferential direction.

  The dust cover 12 has the upper mounting portion 48 attached to the bound stopper 10 as shown in FIGS. That is, the upper mounting portion 48 of the dust cover 12 is extrapolated to the connecting portion 26 of the bound stopper, and the locking projection 50 of the upper mounting portion 48 is fixed to the locking portion 38 of the mounting member 34 fixed to the connecting portion 26. The axial end of the dust cover 12 is attached to the attachment member 34 of the bound stopper 10 by being locked in the axial direction. Since the locking protrusion 50 of the present embodiment is thinned with the outer peripheral side being cut into a groove shape, the insertion guide portion 54 of the locking protrusion 50 is axially connected to the locking portion 38 of the mounting member 34. In this way, the locking protrusion 50 can be passed through the outer peripheral side of the locking portion 38 in the axial direction while being pushed outward by the locking portion 38. Then, when the locking projection 50 inserted above the locking portion 38 is released from the diameter expansion deformation, the locking projection 50 is locked in the locking portion 38 of the mounting member 34 in the axial direction. It has become so.

Here, the attachment member 34 to which the dust cover 12 is attached is provided at a position away from the cylindrical main body portion 14 in the axial direction and the direction perpendicular to the axis. More specifically, as shown in FIG. 2, the attachment member 34 is disposed at a position separated by a predetermined distance d ₁ outward (downward) in the axial direction with respect to the cylindrical main body 14, and the attachment member 34 is located at a distance to a predetermined distance d ₂ by the outer peripheral side with respect to (the outer peripheral surface of the thick portion of the lowermost end of the cylindrical main body 14) the inner peripheral end of the base portion 24. In the present embodiment, the attachment member 34 is disposed at a position deviated from the cylindrical main body portion 14 in the axial direction and the direction perpendicular to the axial direction, and is disposed below the lowermost end of the cylindrical main body portion 14. In addition, it is disposed on the outer peripheral side of the maximum outer diameter portion of the cylindrical main body portion 14. In addition, since the buffer protrusion 18 is additionally provided with respect to the cylindrical main body part 14, the lower end of the cylindrical main body part 14 is grasped except for the buffer protrusion 18. Further, in FIG. 2, the inner peripheral end of the base portion 24 is illustrated by a two-dot chain line.

  Further, the upper end portion of the dust cover 12 attached to the bound stopper 10 is covered upward by a hook-shaped protrusion 32 protruding from the outer peripheral end portion of the base portion 24, and the upper opening of the dust cover 12 is covered with water. This makes it difficult for foreign objects to enter. In particular, in this embodiment, the upper surface of the base 24 including the bowl-shaped protrusion 32 is an inclined surface inclined downward toward the outer periphery, and water or the like is guided to the outer periphery without entering the upper opening of the dust cover 12. It has come to be.

  As shown in FIG. 3, the bound stopper 10 is attached to a vehicle by being attached to a shock absorber 62 constituting a suspension mechanism of the automobile.

  The shock absorber 62 includes a cylinder 64 attached to a wheel side (not shown) and a piston rod 66 extending upward from the cylinder 64 and attached to a vehicle body side (not shown). The cylindrical main body portion 14 of the bound stopper 10 is extrapolated to the piston rod 66, and the upper end portion of the cylindrical main body portion 14 is attached to a spring receiving member 68 attached to the piston rod 66 via an upper mount (not shown). On the other hand, it is non-adhesively fitted. Although the spring receiving member 68 is not particularly limited, in the present embodiment, the spring receiving member 68 is a metal fitting having a dish shape that is opposite in its entirety, and the deep bottom portion at the center in the radial direction is outside the upper end portion of the bound stopper 10. The outer periphery of the coil spring 70 supports the upper end of the coil spring 70.

  The cylinder 64 of the shock absorber 62 is provided with a cylinder cap 72 at the upper end. The cylinder cap 72 is provided with a plurality of fitting protrusions 74 protruding toward the outer periphery, and the fitting protrusions 74 are fitted into a circumferential groove 58 formed in the lower mounting portion 56 of the dust cover 12. As a result, the lower end of the dust cover 12 is attached to the cylinder 64.

  As described above, the upper end of the bound stopper 10 is attached to the piston rod 66 via the spring receiving member 68, and the lower end is attached to the cylinder 64 via the dust cover 12. Yes. The dust cover 12 is arranged axially downward with respect to the cylindrical main body portion 14 of the bound stopper 10 that is externally attached to the piston rod 66, and the upper end portion of the cylinder 64 that is a sliding portion of the shock absorber 62 ( The outer periphery of the piston rod 66 is covered with the dust cover 12.

  For example, when the shock absorber 62 tends to contract excessively due to a large input from the road surface, the cylindrical main body portion 14 of the bound stopper 10 is compressed in the axial direction between the spring receiving member 68 and the cylinder 64, and the shock absorber 62. The amount of shrinkage is elastically limited.

  In the bound stopper 10 according to the present embodiment, when the stopper action accompanied by the compressive deformation of the cylindrical main body portion 14 is performed, the dust cover 12 has a hard attachment whose deformation rigidity is larger than that of the cylindrical main body portion 14. Since it is attached to the member 34, separation of the bound stopper 10 and the dust cover 12 due to elastic deformation of the cylindrical main body portion 14 is prevented. In particular, since the attachment member 34 is fixed to the cylindrical main body 14 via the base 24 and the connecting portion 26, the load input to the cylindrical main body 14 is not easily transmitted to the attachment member 34. Therefore, separation of the dust cover 12 due to deformation of the mounting member 34 is also prevented.

  Further, in the bound stopper 10, when a stopper load is input to the cylindrical main body portion 14, the elastic deformation of the lower end portion of the cylindrical main body portion 14 is difficult to be restrained by the attachment member 34 having a large deformation rigidity, and the stopper action is buffered. Has come to be demonstrated.

  That is, as shown in FIG. 2, the attachment member 34 of the bound stopper 10 is disposed on the outer peripheral side of the cylindrical main body portion 14 by the base portion 24 protruding from the cylindrical main body portion 14 to the outer periphery, and from the base portion 24. The connecting portion 26 protruding downward in the axial direction is disposed on the outer side in the axial direction than the cylindrical main body portion 14. And when the cylindrical main-body part 14 elastically deforms, the restraint by the attachment member 34 of the cylindrical main-body part 14 is reduced by the shear deformation of the base 24, and the shear deformation of the connection part 26, Therefore The cylindrical main-body part 14 Is allowed with a small spring constant in both the axial direction and the direction perpendicular to the axis. Thus, in the bound stopper 10 of the present embodiment, the spring constant of the cylindrical main body portion 14 can be prevented from increasing due to the fixing of the mounting member 34, and the low spring characteristics of the cylindrical main body portion 14 can be prevented. An excellent buffering action can be obtained.

Furthermore, the axial minimum thickness dimension (t ₁ ) of the base 24 is smaller than the radial minimum thickness dimension (T) of the cylindrical main body 14 (t ₁ <T), and the spring constant of the base 24 is Since it is smaller than the spring constant of the cylindrical main body 14, the elastic deformation of the cylindrical main body 14 is easily allowed by the elastic deformation of the base 24. Thereby, the amount of elastic deformation of the cylindrical main body portion 14 is hardly restricted by the mounting member 34, and the stopper action of the cylindrical main body portion 14 is exerted in a buffering manner.

Furthermore, the radial minimum thickness dimension (t ₂ ) between the base 24 and the fixing portion 34 of the connecting portion 26 is larger than the radial minimum thickness dimension (T) of the cylindrical main body 14. The spring constant of the connecting portion 26 is smaller than the spring constant of the cylindrical main body portion 14 (t ₂ <T). Thereby, the restriction | limiting of the elastic deformation amount of the cylindrical main-body part 14 by the attachment member 34 is reduced more, and a buffering stopper effect | action is implement | achieved by the elastic deformation of the cylindrical main-body part 14. FIG.

  Thus, since the base portion 24 is thin in the axial direction and the connecting portion 26 is thin in the direction perpendicular to the axis, the cylindrical main body portion 14 is in either the axial direction or the direction perpendicular to the axis. Even in the case of elastic deformation, the low spring characteristics due to the shear spring components of the base portion 24 and the connecting portion 26 effectively reduce the restraint by the mounting member 34 of the cylindrical main body portion 14.

  Further, since the base portion 24 is provided so as to protrude from the lower end portion in the axial direction of the cylindrical main body portion 14 to the outer periphery, the attachment member 34 can be disposed on the outer side in the axial direction of the cylindrical main body portion 14 by the short connecting portion 26. it can.

  Further, since the connecting portion 26 is provided so as to protrude downward in the axial direction from the outer peripheral end portion of the base portion 24, the attachment portion having a size corresponding to the attachment portion of the dust cover 12 without making the base portion 24 longer than necessary. The connecting portion 26 to which the member 34 is fixed can be provided efficiently, and the mounting member 34 can be arranged on the outer periphery rather than the cylindrical main body portion 14.

  In the present embodiment, the mounting member 34 having an inner diameter larger than the outer diameter of the cylindrical main body 14 is arranged on the substantially same central axis as the cylindrical main body 14 so as to be separated in the axial direction. Thus, the attachment member 34 is disposed at a position away from the cylindrical main body portion 14 in the axial direction and the direction perpendicular to the axis. As a result, even if the mounting member 34 affects the deformation characteristics of the cylindrical main body 14, the deformation characteristics are similarly affected over the entire circumference. Deformation is prevented.

  FIG. 4 shows a bound stopper 80 as a second embodiment of the present invention with a dust cover 82 attached. The bound stopper 80 is integrally provided with a cover mounting portion 84 at the lower end portion of the cylindrical main body portion 14. In addition, in the following description, about the member and site | part substantially the same as 1st embodiment, description is abbreviate | omitted by attaching | subjecting the same code | symbol in a figure.

  More specifically, the cover mounting portion 84 is integrally provided with a base portion 24 that protrudes outward from the cylindrical main body portion 14 and a connecting portion 86 that protrudes downward from the base portion 24 in the axial direction. The connecting portion 86 has a substantially cylindrical shape as a whole, and protrudes downward in the axial direction from the outer peripheral portion of the base portion 24.

  An attachment member 88 is fixed to the lower end portion of the connecting portion 86. The attachment member 88 is integrally provided with a fixing portion 90 having a substantially cylindrical shape and a substantially annular plate-shaped locking portion 92 protruding from the lower end of the fixing portion 90 toward the inner periphery. The attachment member 88 is formed of metal or hard synthetic resin, like the attachment member 34 of the first embodiment, and has a deformation rigidity larger than that of the cylindrical main body portion 14. In this embodiment, the attachment member 88 is a press. A connecting portion between the fixing portion 90 and the locking portion 92 formed by a metal fitting has an arcuate curved shape.

  Note that the attachment member 88 may be formed in an L-shaped cross section having a fixing portion 90 and a locking portion 92 in advance before being fixed to the connecting portion 86, but a cylinder that extends linearly in the axial direction with a substantially constant cross section. The locking portion 92 may be formed later by being formed in a shape and bending the lower portion to the inner peripheral side after being fixed to the connecting portion 86. According to this, it is possible to prevent the locking portion 92 from complicating the parting of the vulcanization mold used for the vulcanization molding of the cylindrical main body portion 14 and the cover attachment portion 84.

  A dust cover 82 is attached to the attachment member 88. The dust cover 82 includes an upper mounting portion 94 above the bellows portion 40. The upper mounting portion 94 has a substantially cylindrical shape as a whole, and a locking protrusion 96 that protrudes to the outer periphery is formed at an axially intermediate portion. The locking projection 96 includes a generally annular plate-shaped retaining portion 98 that extends in a direction perpendicular to the axis, and a tapered cylindrical shape having a small diameter upward, and an insertion guide that projects upward from the outer peripheral end of the retaining portion 98. The stopper 100 is overlapped with the locking portion 92 of the mounting member 88 from above in the axial direction and locked in the axial direction, whereby the dust cover 82 is mounted on the bound stopper 80. It is like that. When the locking projection 96 is inserted into the mounting member 88 of the bound stopper 80 from below, the locking portion 92 of the mounting member 88 comes into contact with the insertion guide portion 100 of the locking projection 96, thereby The stop projection 96 is deformed in a reduced diameter so that the locking projection 96 can pass upward on the inner peripheral side of the locking portion 92.

  Here, also in the bound stopper 80 of the present embodiment, the mounting member 88 is disposed at a position that is deviated in the axial direction and the direction perpendicular to the axial direction with respect to the cylindrical main body portion 14 of the bound stopper 80 as in the first embodiment. Has been.

  That is, the upper end of the fixing portion 90 of the mounting member 88 is positioned away from the lower end of the cylindrical main body portion 14 in the axial direction, and the mounting member 88 and the cylindrical main body portion 14 are projected in the direction perpendicular to the axial direction. It is arranged in a position that does not overlap. Further, the locking portion 92 of the mounting member 88 is located on the outer periphery of the inner peripheral end of the base portion 24, and the mounting member 88 is disposed at a position that does not overlap the cylindrical main body portion 14 in the axial projection.

  Also in the bound stopper 80 having the structure according to this embodiment, the deformation restriction of the cylindrical main body portion 14 due to the mounting member 88 is reduced and the cylindrical main body portion 14 is soft as in the first embodiment. Since the spring characteristics are realized, the stopper action is buffered.

  The shape of the mounting member and the connection structure between the mounting member and the dust cover are not particularly limited. Specifically, for example, the protruding dimension of the engaging portion of the mounting member from the fixing portion changes on the circumference, and after the upper mounting portion of the dust cover is inserted into the engaging portion, the dust cover is used as the mounting member. Alternatively, a twist lock structure in which a locking projection provided partially on the circumference of the upper mounting portion is locked to the engaging portion of the mounting member by rotating the upper mounting portion.

  As mentioned above, although embodiment of this invention was explained in full detail, this invention is not limited by the specific description. For example, the structure of the cylindrical main body 14 is merely an example, and should not be construed in a limited manner by the detailed description of the first and second embodiments. Specifically, for example, the shape, size, number, and the like of the annular groove 16 can be appropriately changed according to required stopper performance.

  Further, the base 24 can be provided at the axially intermediate portion or the axial upper end of the cylindrical main body portion 14. Further, the connecting portion 26 may be provided so as to protrude in the axial direction from the radial intermediate portion of the base portion 24.

  Furthermore, although the hook-shaped protrusion 32 of the first embodiment is provided so as to protrude from the base 24 to the outer periphery, for example, it may be provided on the connecting part 26 above the attachment member 34.

  The structure of the dust cover is not particularly limited. For example, the small valley portion 46 included in the dust covers 12 and 82 of the first and second embodiments is effective for obtaining a large expansion / contraction stroke of the bellows portion 40. However, it is not essential and can be omitted.

10, 80: Bound stopper, 12, 82: Dust cover, 14: Cylindrical main body part, 24: Base part, 26, 86: Connection part, 32: Hook-like protrusion part, 34, 88: Mounting member, 36, 90: Adhering part, 38, 92: Locking part, 62: Shock absorber, 66: Piston rod

Claims (6)

A cylindrical main body part that is externally attached to the piston rod of the shock absorber and elastically limits the amount of contraction and deformation of the shock absorber; and a separate dust cover that covers the sliding portion of the shock absorber A bound stopper that can be attached to the main body,
The cylindrical main body part is integrally formed with a base part protruding to the outer periphery, and the base part is integrally formed with a connecting part protruding in the axial direction.
An annular mounting member whose deformation rigidity is larger than that of the cylindrical main body portion is fixed to the connecting portion, and an axial end portion of the dust cover is attached to the mounting member. The bound stopper, wherein the attachment member is disposed on the axially outer side with respect to the cylindrical main body portion, and the attachment member is disposed on an outer peripheral side with respect to an inner peripheral end of the base portion.   The bound stopper according to claim 1, wherein the axial minimum thickness dimension of the base portion is smaller than the radial minimum thickness dimension of the cylindrical main body portion.   The bound stopper according to claim 1 or 2, wherein the base portion is provided so as to protrude from an axial end portion of the cylindrical main body portion to the outer periphery.   The bound stopper as described in any one of Claims 1-3 with which the said connection part is protruded and provided in the axial direction from the outer peripheral edge part of the said base.   Any one of Claims 1-4 in which the hook-shaped protrusion part which covers the axial direction edge part of the said dust cover attached to the said cylindrical main-body part protrudes in the outer periphery from either the said base part or the said connection part. The bound stopper according to claim 1.   The cylindrical attachment part to which the said attachment member adheres to the said connection part, and the latching | locking part which protrudes from the said fixation part to an orthogonal axis direction, and the said dust cover is latched in an axial direction are integrated. The bound stopper according to any one of 1 to 5.

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