JP2017115940A - Cushion body for upper support - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cushion body for upper support having a new structure in which a spring constant in an axial direction can be set low.SOLUTION: This invention is a cushion body 10 for an upper support provided with a cylindrical elastic body 12 arranged under a pre-compressed state between opposing surfaces between a vehicle body panel 44 that is externally inserted to a piston rod 42 of a shock absorber and the piston rod 42 is inserted and passed and a fitting member 48 arranged at the piston rod 42. An inner diameter size of the cylindrical elastic body 12 is set to be larger than an outer diameter size of the piston rod 42, a peripheral approaching part 28 that is most nearly adjacent to the fitting member 48 under a pre-compression state at an axial end surface at the fitting member 48 for the cylindrical elastic body 12 is positioned at a more outer periphery than the minimum outer diameter part of the cylindrical elastic body 12.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a cushion body constituting an upper support for vibration-proof coupling of a piston rod of a shock absorber in a suspension mechanism of an automobile to a vehicle body panel.

  2. Description of the Related Art Conventionally, there has been known an upper support that connects a piston rod of a shock absorber in a vehicle suspension mechanism to a vehicle body in a vibration-proof manner. As shown in Japanese Patent Application Laid-Open No. 10-331899 (Patent Document 1), this upper support includes a cylindrical vibration-proof rubber that sandwiches a vehicle body panel of a vehicle body up and down. The anti-vibration rubber is extrapolated to the piston rod, and the anti-vibration rubber is disposed in a pre-compressed state between the opposing surfaces of the vehicle body panel and the mounting member fixed to the piston rod. The shock absorber is connected to the vehicle body in a vibration-proof manner.

  By the way, in the upper support, it is desirable to set a small spring constant in the axial direction of the vibration-proof rubber in order to realize a good riding comfort of the automobile.

  However, in the upper support described in Patent Document 1, the inner peripheral surface of the vibration isolating rubber is superimposed and restrained on the piston rod, and the vibration isolating rubber has a reduced axial dimension. It was difficult to set the axial spring constant small.

Japanese Patent Laid-Open No. 10-331899

  The present invention has been made in the background of the above-mentioned circumstances, and a solution to the problem is to provide a cushion structure for an upper support having a novel structure in which the axial spring constant can be set small. It is in.

  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.

  The inventor reduces or eliminates the restraint of the cylindrical elastic body by the piston rod by separating the inner peripheral surface of the cylindrical elastic body constituting the cushion body for the upper support from the outer peripheral surface of the piston rod. The axial elastic constant of the cylindrical elastic body can be set small by increasing the axial dimension while suppressing the dimension of the cylindrical elastic body in the direction perpendicular to the axis and making the cylindrical elastic body vertically long. I thought it was.

  However, as a result of further studies and experiments conducted by the inventor, a new problem occurs when trying to make the cylindrical elastic body into a vertically long shape while allowing elastic deformation to the inner peripheral side of the cylindrical elastic body. I got the knowledge that I could do it. In other words, in the case of a cylindrical elastic body having a small axial spring constant as described above, the cylindrical elastic body is compressed vertically between the opposing surfaces of the vehicle body panel and the mounting member and attached to the vehicle. The elastic body is liable to bend not only in the axial direction but also in a bending state, and it may be difficult to stably mount the elastic body on the vehicle in the correct mounting state.

  Therefore, the present inventor has made the present invention in order to solve such a newly generated problem while enabling the axial spring constant of the cylindrical elastic body to be set small. In other words, the first aspect of the present invention is pre-compressed between the opposing surfaces of the body panel through which the piston rod is inserted and the mounting member provided on the piston rod. A cushion body for an upper support having a cylindrical elastic body disposed in a state where the inner diameter dimension of the cylindrical elastic body is larger than the outer diameter dimension of the piston rod, On the axial end surface of the elastic body on the mounting member side, the circumferential proximity portion closest to the mounting member in a state before pre-compression is located on the outer circumference than the minimum outer diameter portion of the cylindrical elastic body. Is a feature.

  According to the cushion body for the upper support having the structure according to the first aspect of the present invention, the cylindrical elastic body and the attachment member first come into contact with each other at the circumferential proximity portion when mounted on the vehicle. When the body is compressed in the axial direction between the vehicle body panel and the mounting member, first, an axially inward force acts on the outer peripheral side of the smallest outer diameter portion of the cylindrical elastic body. As a result, a moment in the direction of expanding toward the outer peripheral side acts on the axial end of the cylindrical elastic body on the mounting member side to prevent buckling deformation so that the cylindrical elastic body is bent. Can do. In particular, the proximity portion where the cylindrical elastic body and the mounting member are closest is provided as a whole as a whole, so that the input is dispersed and concentrated without being concentrated at a specific radial position. Buckling deformation that is bent so as to enter inward in the radial direction at the position is prevented.

  By preventing buckling deformation of the cylindrical elastic body in this way, a gap is formed between the cylindrical elastic body and the piston rod, and deformation to the inner periphery of the cylindrical elastic body is allowed. However, the cylindrical elastic body can stably generate the predetermined precompression deformation. Accordingly, it is possible to reduce the restraint of the cylindrical elastic body by the piston rod and to set the spring constant in the axial direction of the cylindrical elastic body to be small, and to simplify the mounting work on the vehicle.

  In addition, since the buckling deformation of the cylindrical elastic body is prevented, a gap is formed between the cylindrical elastic body and the piston rod, and the axial dimension of the cylindrical elastic body is increased to increase the axial spring constant. It is also possible to adopt a vertically long cylindrical elastic body having a small size, and a large degree of freedom in adjusting the axial spring constant can be obtained.

  According to a second aspect of the present invention, in the cushion member for the upper support described in the first aspect, the axial end face of the cylindrical elastic body on the side of the attachment member projects toward the attachment member. A circumferential contact projection is provided, and the circumferential contact projection constitutes the circumferential proximity portion.

  According to the second aspect, it is possible to form the circumferential proximity portion to the mounting member in the cylindrical elastic body without providing the mounting member with a protruding portion toward the cylindrical elastic body.

  According to a third aspect of the present invention, in the cushion body for an upper support described in the first or second aspect, the circumferential proximity portion is continuously provided over the entire circumference of the cylindrical elastic body. It is what.

  According to the third aspect, since the load at the initial contact between the mounting member and the cylindrical elastic body is input over the entire circumference, the axial end of the cylindrical elastic body on the mounting member side is moved to the outer peripheral side. The moment in the expanding direction acts on the cylindrical elastic body over the entire circumference, and buckling deformation of the cylindrical elastic body that falls in the specific radial direction is prevented.

  According to a fourth aspect of the present invention, in the cushion member for the upper support described in any one of the first to third aspects, an axial end portion of the cylindrical elastic body on the vehicle body panel side includes: A positioning member to be fitted into the insertion hole of the vehicle body panel through which the piston rod is inserted is fixed.

  According to the fourth aspect, the cylindrical elastic body and the vehicle body panel are positioned by the positioning member, and the cylindrical elastic body can be easily attached to the vehicle body panel in a correct relative positional relationship. In addition, since the axial end of the cylindrical elastic body on the vehicle body panel side is restrained by the positioning member, the cylindrical elastic body is prevented from being deformed into distortion at the axial end of the vehicle body panel side. The vehicle mounting state can be realized more stably.

  According to a fifth aspect of the present invention, in the cushion member for the upper support described in any one of the first to fourth aspects, the cylindrical elastic body protrudes toward the inner periphery. Are formed integrally, and the inner protrusion is positioned on the mounting member side with respect to the smallest outer diameter portion of the cylindrical elastic body, and the inner protrusion protrudes toward the projecting tip. It is narrow in the axial direction of the elastic body.

  According to the fifth aspect, the elastic deformation of the cylindrical elastic body toward the inner peripheral side is limited by the contact of the inward protrusion with the piston rod, and the buckling deformation of the cylindrical elastic body is more advantageously prevented. Is done. In particular, by providing the inward protrusion on the attachment member side with respect to the minimum outer diameter portion that is easily deformed at the initial stage of input, buckling deformation of the cylindrical elastic body can be efficiently prevented. Further, since the inward protrusion is narrower in the axial direction toward the protruding tip, the axial spring constant is increased by the inward protrusion coming into contact with the piston rod, and the inward protrusion piston rod Generation of abnormal noise due to rubbing against the surface can be reduced.

  According to a sixth aspect of the present invention, in the cushion body for an upper support described in any one of the first to fifth aspects, the outer peripheral surface of the cylindrical elastic body is an axial direction of the cylindrical elastic body. Thus, the cylindrical elastic body is provided with a constricted tapered surface that gradually becomes smaller in diameter toward the minimum outer diameter portion.

  According to the sixth aspect, since the outer peripheral surface of the cylindrical elastic body is a constricted tapered surface, the axial spring constant of the cylindrical elastic body can be easily set small, and the ride comfort of the vehicle can be improved. Can be illustrated. In addition, the cylindrical elastic body has an aspect in which the axial end of the cylindrical elastic body on the mounting member side extends to the outer peripheral side upon input to the circumferential proximity portion by contact between the cylindrical elastic body and the mounting member. Deformation is easily induced, and buckling deformation of the cylindrical elastic body in the specific radial direction can be avoided more advantageously.

  According to a seventh aspect of the present invention, in the cushion member for an upper support described in any one of the first to sixth aspects, the cylindrical elastic body is provided at a minimum outer diameter portion of the cylindrical elastic body. Grooves that are open in the outer peripheral surface of the rim and are continuous in the circumferential direction over the entire circumference are formed.

  According to the seventh aspect, the axial spring constant of the cylindrical elastic body can be easily reduced by the formation of the groove portion, and the riding comfort of the vehicle can be improved. Further, when the cylindrical elastic body is input due to the contact of the mounting member with the circumferential proximity portion, the elastic deformation of the cylindrical elastic body that crushes the groove portion is induced, so that the mounting member side is closer to the groove portion in the cylindrical elastic body. In this portion, the moment in the direction of moving the axial end on the mounting member side to the outer periphery is likely to act on the entire periphery. Therefore, buckling deformation of the cylindrical elastic body is made difficult to occur, and a predetermined mounting state is easily realized.

  According to an eighth aspect of the present invention, in the cushion body for the upper support described in any one of the first to seventh aspects, the tubular elastic body is in a vehicle mounted state in which the cylindrical elastic body is precompressed. The body is extrapolated with a gap to the piston rod.

  According to the eighth aspect, since the inner peripheral surface of the cylindrical elastic body and the outer peripheral surface of the piston rod are separated at least partially in the vehicle mounted state, the cylindrical elastic body is not easily restrained by the piston rod. Thus, the axial spring constant of the cylindrical elastic body in the vehicle mounted state can be easily set smaller.

  According to the present invention, at the time of mounting on the vehicle, the cylindrical elastic body and the attachment member first come into contact with each other at the circumferential proximity portion located on the outer periphery rather than the minimum outer diameter portion of the cylindrical elastic body. As a result, the cylindrical elastic body is subjected to a moment in a direction in which the axial end on the mounting member side is expanded to the outer peripheral side, and the cylindrical elastic body is buckled and deformed so as to fall in a specific radial direction. Can be prevented. And since buckling deformation of a cylindrical elastic body is prevented, it becomes possible to reduce restraint by a piston rod of a cylindrical elastic body, and to make a cylindrical elastic body into a more vertically long shape. It becomes possible, and the axial direction spring constant of a cylindrical elastic body can be set small.

It is a longitudinal cross-sectional view which shows the upper cushion body as 1st embodiment of this invention, Comprising: The figure corresponded in the II cross section of FIG. The top view of the upper cushion body shown in FIG. The fragmentary sectional view which expands and shows the principal part of the upper cushion body of FIG. The longitudinal cross-sectional view which shows the upper cushion body of FIG. 1 in a vehicle mounting state. Sectional drawing which shows the upper cushion body as 2nd embodiment of this invention. The top view which shows the upper cushion body as 3rd embodiment of this invention.

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

  1 and 2 show an upper cushion body 10 as a first embodiment of an upper support cushion body according to the present invention. The upper cushion body 10 has a structure in which a positioning member 14 is fixed to a cushion rubber 12 as a cylindrical elastic body. In the following description, the vertical direction means the vertical direction in FIG. 1 that is the axial direction of the upper cushion body 10 in principle.

  More specifically, the cushion rubber 12 has a substantially cylindrical shape as a whole, and the upper portion is a cylindrical portion 16.

  The cylindrical portion 16 of the cushion rubber 12 has a cylindrical surface whose inner peripheral surface 18 has a substantially circular cross section and extends linearly in the vertical direction, and a conical taper in which the outer peripheral surface 20 gradually decreases in the axial direction. The outer peripheral surface 20 has a minimum diameter at the constricted portion set in the middle in the axial direction. Further, the inner diameter dimension of the cylindrical portion 16 is larger than the outer diameter dimension of a piston rod 42 (described later), and is larger than the outer diameter dimension of a sleeve 54 (described later) inserted into the piston rod 42. .

  Furthermore, a groove portion 22 that opens to the outer peripheral surface 20 at a constricted portion where the diameter of the outer peripheral surface 20 is minimum is continuously formed in the cylindrical portion 16 over the entire periphery. The groove portion 22 has a groove cross-sectional shape that gradually expands in the axial direction toward the outer peripheral opening side. In the present embodiment, the wall inner surface of the groove portion 22 is a curved surface, and a smooth groove cross section without a break point. It has a shape.

  As described above, the cylindrical portion 16 of the cushion rubber 12 has the outer peripheral surface 20 formed of a constricted tapered surface and the groove portion 22, so that the outermost portion of the groove portion 22 (bottom) is outside the cushion rubber 12. The diameter is the smallest. In other words, the minimum outer diameter portion of the cushion rubber 12 is set to the deepest portion of the groove portion 22. In addition, the opening edge part of the groove part 22 and the outer peripheral surface 20 of the cylindrical part 16 are smoothly continued by the curved surface, and the stress concentration in the opening edge part of the groove part 22 is eased.

  Further, an inward projection 24 that protrudes toward the inner periphery is integrally formed at the upper end of the cylindrical portion 16 of the cushion rubber 12. As shown in FIG. 3, the inward projection 24 has a longitudinal cross-sectional shape that becomes narrower in the axial direction toward the projecting tip. In this embodiment, the inward projecting portion 24 has a substantially constant semicircular cross section over the entire circumference. Are formed continuously. The inward protruding portion 24 of the present embodiment is formed at the upper end portion of the cushion rubber 12, as long as it is located on the upper mounting bracket 48 side with respect to the minimum outer diameter portion of the cylindrical portion 16 of the cushion rubber 12. Further, it may be formed at an intermediate portion in the axial direction of the cylindrical portion 16. The upper surface of the inner protrusion 24 is smoothly continuous with the upper end surface of the tubular portion 16, and the lower surface of the inner protrusion 24 is smoothly continuous with the inner peripheral surface 18 of the tubular portion 16. .

  Furthermore, an outer protrusion 26 projecting outward is integrally formed at the upper end of the cylindrical portion 16 of the cushion rubber 12. The outward protrusion 26 is provided in a flange shape at the upper end of the cylindrical portion 16 and is continuously provided over the entire circumference. The outward protrusion 26 protrudes to the outer periphery from the minimum outer diameter portion (the deepest portion of the groove portion 22 shown by a broken line in FIG. 2) on the outer peripheral surface 20 of the cylindrical portion 16. In this embodiment, the outward protrusion 26 is a tapered surface. It protrudes to the outer peripheral side rather than the extended line (one-dot chain line in FIG. 3) of the configured outer peripheral surface 20. Note that the upper surface of the outward projection 26 continuously spreads out on the substantially same plane as the upper end surface of the tubular portion 16, and cooperates with the upper end surface of the tubular portion 16 to cover the upper end surface of the cushion rubber 12. It is composed.

  Further, a circumferential contact protrusion 28 protruding upward is integrally formed on the outward protrusion 26 of the cushion rubber 12. The circumferential contact protrusion 28 continuously extends over the entire circumference with a substantially constant cross-sectional shape that gradually becomes narrower in the radial direction upward, and has a substantially semicircular cross-section in the present embodiment. Thus, the upper end surface of the cushion rubber 12 is positioned such that the outer peripheral end portion where the circumferential contact protrusion 28 is formed is located above the other portion (the inner peripheral portion of the circumferential contact protrusion 28). ing. Further, as apparent from the fact that the circumferential contact protrusion 28 is formed on the upper surface of the outer protrusion 26, the bottom of the groove portion 22 which is the smallest outer diameter portion of the cylindrical portion 16 in the cushion rubber 12. Is located on the outer circumference.

  Further, a fixing portion 30 is integrally formed below the cylindrical portion 16 in the cushion rubber 12. The fixing portion 30 constitutes a lower portion of the cushion rubber 12 and has substantially the same inner diameter as that of the cylindrical portion 16 and has an outer diameter larger than that of the cylindrical portion 16. The upper surface extends in a substantially annular shape on the outer periphery than the cylindrical portion 16. Further, since the inner diameter dimension of the fixing portion 30 is substantially the same as the inner diameter dimension of the cylindrical portion 16, the inner diameter dimension of the fixing portion 30 is the outer diameter dimension of the piston rod 42 (described later) and the outer diameter of the sleeve 54 (described later). The inner diameter of the cushion rubber 12 is made larger than the outer diameter of the piston rod 42 and the outer diameter of the sleeve 54. However, the inner diameter dimension of the cushion rubber 12 may be substantially the same as the outer diameter dimension of the sleeve 54 or may be smaller than the outer diameter dimension of the sleeve 54 at the protruding tip of the inner protrusion 24. In short, the inner diameter dimension of the cushion rubber 12 does not need to be larger than the outer diameter dimension of the piston rod 42 and the outer diameter dimension of the sleeve 54 over the entire axial direction, and may be larger at least partially.

  The positioning member 14 is vulcanized and bonded to the fixing portion 30. The positioning member 14 is in the shape of an annular plate having a circular through hole at the center in the radial direction, and has a stepped stepped annular plate shape that is positioned upward as it goes to the outer periphery. The positioning member 14 of the present embodiment is a press fitting, and a positioning projection 32 that protrudes downward is formed at the inner peripheral end of the positioning member 14. The positioning protrusion 32 is formed continuously over the entire circumference, and the inner peripheral end of the positioning member 14 is integrally formed by bending downward by press working.

  The positioning member 14 is fixed to the fixing portion 30 of the cushion rubber 12. In the present embodiment, the inner peripheral portion of the positioning member 14 is fixed to the fixing portion 30 in an embedded state, and not only the upper surface but also the lower surface and the inner and outer peripheral surfaces are covered with the fixing portion 30, while the outer peripheral portion of the positioning member 14 The upper surface and the inner peripheral surface are overlapped and fixed to the fixing portion 30, and the lower surface and the outer peripheral surface are exposed from the fixing portion 30. The protruding tip (lower end) of the positioning protrusion 32 is formed so as to protrude further downward with respect to the lower surface of the fixing part 30 that covers the inner peripheral portion of the positioning member 14 that is out of the positioning protrusion 32. Further, the inner diameter of the positioning member 14 is larger than the inner diameter of the cushion rubber 12, and the inner peripheral surface of the positioning member 14 is covered with the cushion rubber 12 (adhering portion 30).

  The upper cushion body 10 having such a structure constitutes the upper support 34. The upper support 34 includes an upper cushion body 10 and a lower cushion body 36, as shown in FIG. The lower cushion body 36 is formed of a substantially cylindrical rubber elastic body or resin elastomer. In the present embodiment, a protrusion 38 that protrudes toward the inner periphery is formed continuously at the lower end, and water or sand dust is formed. Intrusion of foreign matter such as is prevented. Further, the lower cushion body 36 of this embodiment is integrally formed with a cover portion 40 that extends to the outer periphery and extends downward from the outer peripheral end.

  The upper cushion body 10 and the lower cushion body 36 are extrapolated to the piston rod 42 of the shock absorber that constitutes the suspension mechanism, respectively, and the upper cushion body 10 and the lower cushion body 36 are respectively one above and below the vehicle body panel 44. They are stacked one above the other from the side. An insertion hole 46 is formed through the vehicle body panel 44, and the piston rod 42 is inserted into the insertion hole 46, and the positioning protrusion 32 of the positioning member 14 in the upper cushion body 10 is fitted into the body panel 44. The cushion body 10 is positioned in a direction perpendicular to the axis with respect to the vehicle body panel 44.

  Further, the piston rod 42 has a flat plate-shaped upper mounting bracket 48 as a mounting member superimposed on the upper surface of the upper cushion body 10 and a cup-shaped lower mounting bracket 50 stacked on the lower surface of the lower cushion body 36. It is installed. Between the upper and lower portions of the upper mounting bracket 48 and the bottom wall portion of the lower mounting bracket 50, a cylindrical sleeve 54 that is externally attached to the piston rod 42 is disposed, and the upper mounting bracket 48 and the lower mounting bracket 50 are moved vertically. It is positioned at a predetermined relative distance in the direction. However, if the upper mounting bracket 48 and the lower mounting bracket 50 are relatively positioned in the vertical direction, the sleeve 54 is not essential. For example, the portion located between the upper mounting bracket 48 and the lower mounting bracket 50 of the piston rod 42 has a larger diameter than the portion inserted through the upper mounting bracket 48, and the large diameter portion of the piston rod 42 and the nut If the upper mounting bracket 48 is sandwiched between 64 (described later) and the upper mounting bracket 48 is positioned with respect to the piston rod 42, the sleeve 54 can be omitted. In addition, since the sleeve 54 of this embodiment is fixed to the piston rod 42 in an extrapolated state, it can be substantially regarded as a part of the piston rod 42.

  Furthermore, a reverse cup-shaped support fitting 52 is fixed to the lower mounting fitting 50 by means such as welding. That is, the bottom wall portion of the lower mounting bracket 50 and the upper bottom wall portion of the support bracket 52 are overlapped and fixed vertically, and pass through the bottom wall portion of the lower mounting bracket 50 and the upper bottom wall portion of the support bracket 52. The piston rod 42 is inserted into the fitting hole 56 to be fixed. The support metal fitting 52 has an upper end portion of a dust cover 58 fixed to a peripheral wall portion and a cylindrical bump stopper 60 fitted therein.

  A male threaded portion 62 is provided at the upper end of the piston rod 42 that protrudes upward through the bolt hole 66 of the upper mounting bracket 48, and the upper mounting bracket 48 is tightened by tightening a nut 64 that is screwed onto the male threaded portion 62. Is made to approach the lower mounting bracket 50 in the vertical direction. In the present embodiment, a flange-like engagement portion 68 provided on the piston rod 42 is superimposed on the upper bottom wall portion of the support fitting 52 from below, so that the upper attachment bracket 48 is positioned in the vertical direction of the lower attachment fitting 50. The upper mounting bracket 48 and the lower mounting bracket 50 are set close to each other in the vertical direction by tightening the nut 64.

  Thereby, the cushion rubber 12 of the upper cushion body 10 is compressed vertically between the upper mounting bracket 48 and the vehicle body panel 44, and the lower cushion body 36 is compressed vertically between the vehicle body panel 44 and the lower mounting bracket 50. In this state, the upper support 34 is attached to the vehicle, and the piston rod 42 of the shock absorber is connected to the vehicle body panel 44 of the vehicle body through the upper support 34 in a vibration-proof manner. In the present embodiment, even in the vehicle mounted state, the inner peripheral surface of the cushion rubber 12 of the upper cushion body 10 is separated at least in part from the outer peripheral surface of the sleeve 54 that constitutes the piston rod 42. The cushion rubber 12 is extrapolated with a gap to the sleeve 54.

  Here, in the cushion rubber 12 of the upper cushion body 10 according to the present embodiment, when it is compressed up and down between the upper mounting bracket 48 and the vehicle body panel 44, distortion buckling deformation such as bending does not occur. A compressive deformation in the vertical direction is generated.

  That is, the cushion rubber 12 is provided with a circumferential contact protrusion 28 at the outer peripheral end portion of the upper end surface, and the outer peripheral end portion of the cushion rubber 12 that is a portion where the circumferential contact protrusion 28 is formed has a flat plate shape. It is a circumferential proximity portion that is closer to the upper mounting bracket 48 than other portions. In the present embodiment, the circumferential contact projection 28 is integrally formed on the cushion rubber 12, and the circumferential contact projection 28 protrudes from the cushion rubber 12 toward the upper mounting bracket 48. A circumferential proximity portion is set in the cushion rubber 12 by the upper mounting bracket 48 having a flat bottom surface without providing a protruding portion or the like on the cushion rubber 12 side. By setting such a circumferential proximity portion, when the nut 64 is fastened to the male screw portion 62 and the cushion rubber 12 is compressed up and down between the upper mounting bracket 48 and the vehicle body panel 44, the circumferential shape The outer peripheral end portion of the upper surface of the cushion rubber 12 having the contact protrusion 28 comes into contact with the upper mounting bracket 48 first, and a downward force is preferentially inputted outside the tubular portion 16. In the present embodiment, the circumferential contact protrusion 28 is an annular ridge that extends continuously over the entire circumference, and the circumferential proximity portion is provided continuously over the entire circumference. A load due to contact with the mounting bracket 48 is input over the entire circumference of the cushion rubber 12.

  Further, the circumferential contact projection 28 is located on the outer periphery of the smallest outer diameter portion of the cylindrical portion 16 of the cushion rubber 12, and the circumferential contact projection 28 is in contact with the upper mounting bracket 48 and below. In addition to the compressive force in the vertical direction, a moment in the direction of pushing the upper end of the cylindrical portion 16 toward the outer peripheral side acts on the cushion rubber 12 over the entire circumference. In the present embodiment, the load at the initial contact between the upper mounting bracket 48 and the cushion rubber 12 is input over the entire circumference by the annular circumferential proximity portion (circumferential contact protrusion 28), so that the tubular shape The portion 16 is elastically deformed so that the axial end portion on the upper mounting bracket 48 side expands to the outer peripheral side over the entire circumference, so that the cylindrical portion 16 is more buckled and deformed in the specific radial direction. It is advantageously prevented.

  Thereby, in the cylindrical part 16 of the cushion rubber | gum 12, generation | occurrence | production of the bending-shaped buckling deformation | transformation which deform | transforms so that it may fall down to an inner periphery partially in the circumferential direction can be prevented. As a result, the cylindrical portion 16 of the cushion rubber 12 is subjected to compression deformation in the vertical direction substantially uniformly over the entire circumference by a simple operation of tightening the nut 64, and the vehicle body panel 44 in a predetermined precompression state. It can be interposed between the upper mounting brackets 48.

  Moreover, in the present embodiment, the outer peripheral surface 20 of the cylindrical portion 16 of the cushion rubber 12 is a constricted tapered surface that gradually decreases in diameter from both axial sides toward the minimum outer diameter portion. As a result, when the circumferential contact protrusion 28 is pushed downward by the upper mounting bracket 48, a moment in the direction of expanding the upper portion of the tubular portion 16 toward the outer peripheral side easily acts on the entire circumference. Thus, the cylindrical part 16 is less likely to fall down. In addition, the outer diameter dimension of the cylindrical portion 16 is locally smaller in the formation portion of the groove portion 22, and the minimum outer diameter portion of the cylindrical portion 16 is set by the groove portion 22 that opens to the outer peripheral surface 20. . Therefore, when a downward force is input to the circumferential contact protrusion 28 from the upper mounting bracket 48, a deformation that crushes the groove portion 22 is induced in the tubular portion 16, and the tubular portion 16 is distorted. Is to be blocked. In particular, the groove cross-sectional shape of the groove portion 22 is gradually narrower in the vertical direction toward the bottom, and the bottom (deepest portion) of the groove portion 22 has a substantially annular line shape with a reduced axial width. Therefore, at the time of input to the circumferential contact protrusion 28, the cylindrical portion 16 is stably deformed starting from the bottom of the groove portion 22.

  Since the buckling deformation of the tubular portion 16 is prevented in this way, a gap is formed between the tubular portion 16 and the sleeve 54 constituting a part of the piston rod 42, and the tubular portion 16. Even if deformation to the inner circumference is allowed, the cylindrical portion 16 can be stably precompressed and deformed in the axial direction. Accordingly, it is possible to reduce the restraint by the sleeve 54 of the tubular portion 16 and to set the axial spring constant of the tubular portion 16 to be small, while simplifying the mounting work on the vehicle. In the present embodiment, even in the vehicle mounting state shown in FIG. 4, since the inner peripheral surface 18 of the tubular portion 16 and the outer peripheral surface of the sleeve 54 are separated from each other, the restraint by the sleeve 54 of the tubular portion 16 is further reduced. Thus, the axial spring constant of the cylindrical portion 16 in the vehicle mounted state can be easily set smaller.

  Further, by preventing buckling deformation of the tubular portion 16, the axial dimension of the tubular portion 16 is increased while forming a gap between the tubular portion 16 and the sleeve 54, thereby increasing the axial spring constant. It is also possible to employ a vertically long cylindrical portion 16 having a small size, and a large degree of freedom in adjusting the axial spring constant can be obtained.

  The upper cushion body 10 has a structure in which a hard positioning member 14 is fixed to the cushion rubber 12, and deformation of the lower portion of the cushion rubber 12 is restricted by the positioning member 14. The distorted deformation in the lower part of the is prevented. Moreover, the positioning protrusion 14 of the positioning member 14 is fitted into the insertion hole 46 of the vehicle body panel 44, whereby the cushion rubber 12 and the vehicle body panel 44 are positioned relative to each other by the positioning member 14, and the cushion rubber 12 is moved to the vehicle body panel 44. Can be easily mounted with the correct relative positional relationship.

  Further, an inward protrusion 24 that protrudes toward the inner peripheral side is integrally formed at the upper end of the cylindrical portion 16 of the cushion rubber 12. Thereby, the elastic deformation to the inner peripheral side of the cylindrical part 16 is restrict | limited by contact | abutting to the sleeve 54 of the inward protrusion 24, and the buckling deformation of the cylindrical part 16 is prevented. In particular, in the present embodiment, the inward protrusion 24 is a protrusion that continues in a substantially constant cross-sectional shape over the entire periphery, and the elastic deformation of the tubular portion 16 toward the inner periphery is the inner protrusion 24. Therefore, the buckling deformation of the cylindrical portion 16 is advantageously prevented. Further, since the inward projection 24 is provided at the upper end portion away from the portion (the bottom of the groove portion 22) that can be a bending point at the time of buckling deformation of the cylindrical portion 16, the inward projection 24 is seated. The effect of preventing bending deformation is efficiently exhibited.

  Furthermore, since the inward protrusion 24 has a substantially semicircular cross section that becomes narrower in the axial direction toward the protruding tip, the axial spring constant is increased by the inward protrusion 24 coming into contact with the sleeve 54. In addition, generation of abnormal noise due to rubbing of the inward protrusion 24 against the sleeve 54 can be reduced.

  FIG. 5 shows an upper cushion body 70 as a second embodiment of the present invention. In the following description, members and parts that can be grasped as substantially the same configuration as the first embodiment will be omitted by attaching the same reference numerals.

  In the upper cushion body 70, the cushion rubber 72 is not provided with the circumferential contact protrusion (28) as in the first embodiment, and the upper end surface of the cushion rubber 72 including the upper surface of the outer protrusion 26 is The flat surface extends in a direction substantially perpendicular to the axis. On the other hand, a circumferential thick portion 76 that protrudes toward the tubular portion 16 is integrally formed on the outer peripheral portion of the upper mounting bracket 74 that is virtually illustrated by a two-dot chain line in FIG. The circumferential thick portion 76 does not necessarily have to be continuous over the entire circumference, but in the present embodiment, the circumferential thick portion 76 is provided continuously in a circumferential ring shape with a substantially constant cross-sectional shape.

  The upper mounting bracket 74 is inserted into a bolt hole 66 through a piston rod (not shown) in the same manner as the upper mounting bracket (48) of the first embodiment, and is axially directed to the piston rod by a sleeve 54 and a nut 64. Is positioned. Further, the upper cushion body 70 is extrapolated to the piston rod and overlapped with the upper mounting bracket 74 from below. As a result, as shown in FIG. 5, the circumferential thick portion 76 of the upper mounting bracket 74 is disposed at a position corresponding to the outward projection 26 of the cushion rubber 72, and the outer side of the cushion rubber 72 The protrusion 26 is a cylindrical proximity portion that is closer to the upper mounting bracket 74 than the other portions of the cushion rubber 72. In short, in this embodiment, by forming a portion (circumferential thick portion 76) protruding toward the cylindrical portion 16 on the upper mounting bracket 74, a cylindrical proximity to the outer peripheral end of the upper surface of the cylindrical portion 16 is achieved. The part is set over the entire circumference. In addition, the outward protrusion 26 which is a cylindrical proximity part protrudes to the outer periphery rather than the outer peripheral surface 20 of the cylindrical part 16, and is located in the outer periphery rather than the minimum outer diameter part (bottom of the groove part 22) of the cylindrical part 16. positioned.

  Also in the upper cushion body 70 according to this embodiment, as in the first embodiment, when the cushion rubber 72 is compressed up and down, the deformation mode of the tubular portion 16 is stabilized, It is possible to prevent bending buckling deformation that falls down. Therefore, the inner peripheral surface of the cushion rubber 72 can be separated from the piston rod (sleeve 54), and the cushion rubber 72 can be formed in a vertically elongated shape vertically. Can be set small.

  In addition, in 2nd embodiment, even if the circumferential contact protrusion 28 of 1st embodiment is abbreviate | omitted by employ | adopting the upper attachment metal fitting 74 provided with the circumferential thick part 76, a circumferential proximity | contact part is not. Although it has been shown that it can be configured, for example, the cushion rubber 12 including the circumferential contact protrusion 28 of the first embodiment, and the upper mounting bracket 74 including the circumferential thick portion 76 of the second embodiment; Can also be used in combination. Further, in the upper mounting bracket 74 of the present embodiment, the upper mounting bracket 74 protrudes toward the cushion rubber 72 because the outer peripheral portion is partially thickened. The circumferential proximity portion can also be set in the cushion rubber 72 by projecting it toward the cushion rubber 72 without changing the thickness by bending it in the thickness direction.

  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 specific shape of the circumferential contact protrusion is not particularly limited, and an arbitrary cross-sectional shape can be adopted, and it is not always necessary to be continuous over the entire circumference. That is, as in the upper cushion body 80 shown in FIG. 6, substantially hemispherical contact protrusions 82 are integrally formed at a plurality of locations in the circumferential direction with respect to the outward protrusions 26 that are continuous over the entire circumference. A plurality of contact protrusions 82 arranged side by side in the circumferential direction may constitute a circumferential contact protrusion. In short, the circumferential contact protrusion is not necessarily limited to one in which one protrusion continuously extends in the circumferential direction, and for example, a plurality of protrusions may form a circumferential shape as a whole. . The circumferential shape is not necessarily limited to the circumferential shape, and may be, for example, a polygonal circumferential shape.

  In addition, as long as the circumferential proximity portion is located on the outer periphery of the smallest outer diameter portion of the cylindrical elastic body, the formation position is not limited to the outermost peripheral end of the cylindrical elastic body. Further, the circumferential proximity portion does not need to be provided on the outward projection 26 protruding from the cylindrical portion 16 to the outer periphery as in the first and second embodiments, and is set on the upper surface of the cylindrical portion 16. The outward protrusion 26 can be omitted.

  Further, as shown in the first and second embodiments, in order to stabilize the deformation mode of the cylindrical portion 16, it is desirable that the groove portion 22 opened in the outer peripheral surface 20 of the cylindrical portion 16 is provided, The groove 22 is not essential and can be omitted. Furthermore, in order to stabilize the deformation mode of the cylindrical portion 16, it is desirable to employ a constricted tapered surface on the outer peripheral surface 20 of the cylindrical portion 16, but instead of the constricted tapered surface, for example, a substantially constant It may be a cylindrical surface extending in the axial direction with an outer diameter dimension.

  In addition, the cross-sectional shape of the inward protrusion is not limited to a substantially semicircular shape, and a shape that gradually narrows up and down toward the protruding tip is desirable from the viewpoint of buffering properties, etc., but with a substantially constant vertical dimension. You may protrude to the inner periphery. Furthermore, the inward projection can be omitted.

  Furthermore, the inward protrusion may be in contact with the piston rod in advance in a state where the upper support cushion is mounted on the vehicle, but it is in contact with the piston rod by elastic deformation of the cylindrical elastic body. It may be.

  In the above embodiment, the cylindrical elastic body is separated from the outer periphery of the piston rod even in the vehicle mounted state, but the inner diameter dimension of the cylindrical elastic body is the outer diameter dimension of the piston rod in the non-load input state before the vehicle mounting. If the diameter is larger than that, the cylindrical elastic body may be in contact with the piston rod in a vehicle mounted state in which the cylindrical elastic body is pre-compressed.

  Moreover, although the example which applied the structure based on this invention to the upper cushion body of the upper support was shown in the said embodiment, it is also possible to apply the structure based on this invention to the lower cushion body of an upper support.

10, 70, 80: upper cushion body (cushion body for upper support), 12, 72: cushion rubber (cylindrical elastic body), 14: positioning member, 20: outer peripheral surface, 22: groove portion, 24: inward projection Part, 28: circumferential contact protrusion, 34: upper support, 42: piston rod, 44: body panel, 46: insertion hole, 48, 74: upper mounting bracket, 54: sleeve, 82: contact protrusion

Claims (8)

A cylindrical elastic body that is externally inserted into a piston rod of a shock absorber and disposed in a pre-compressed state between opposing surfaces of a vehicle body panel through which the piston rod is inserted and an attachment member provided in the piston rod. A cushion body for the upper support provided,
The inner diameter of the cylindrical elastic body is larger than the outer diameter of the piston rod,
On the axial end surface of the cylindrical elastic body on the mounting member side, the circumferential proximity portion closest to the mounting member in a state before pre-compression is located on the outer periphery than the minimum outer diameter portion of the cylindrical elastic body. Cushion body for upper support, characterized by   A circumferential contact protrusion that protrudes toward the attachment member is provided on an axial end surface of the cylindrical elastic body on the attachment member side, and the circumferential contact protrusion causes the circumferential proximity protrusion to protrude from the circumferential contact protrusion. The upper support cushion body according to claim 1, which is configured.   The cushion body for an upper support according to claim 1 or 2, wherein the circumferential proximity portion is continuously provided over the entire circumference of the cylindrical elastic body.   The positioning member fitted to the insertion hole of the vehicle body panel through which the piston rod is inserted is fixed to the axial end of the cylindrical elastic body on the vehicle body panel side. A cushion body for an upper support according to claim 1.   The tubular elastic body is integrally formed with an inward protrusion that protrudes toward the inner periphery, and the inward protrusion is positioned closer to the mounting member than the smallest outer diameter portion of the tubular elastic body. The cushion body for upper support according to any one of claims 1 to 4, wherein the inward projection is narrower in the axial direction of the cylindrical elastic body toward the projecting tip.   The outer peripheral surface of the said cylindrical elastic body is provided with the constricted taper surface which becomes a small diameter gradually toward the minimum outer-diameter part of this cylindrical elastic body in the axial direction of this cylindrical elastic body. The cushion body for upper support as described in any one of Claims.   The groove part which opens in the outer peripheral surface of this cylindrical elastic body, and continues in the circumferential direction over the perimeter is formed in the minimum outer-diameter part of the said cylindrical elastic body. The cushion body for the upper support as described in the item.   The upper according to any one of claims 1 to 7, wherein the cylindrical elastic body is extrapolated with a gap to the piston rod in a vehicle-mounted state in which the cylindrical elastic body is precompressed. Cushion body for support.

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