JP4716388B2 - Vibration isolator - Google Patents

Description

  The present invention relates to a vibration isolator for elastically coupling a piston rod of a shock absorber in a suspension mechanism of a vehicle such as an automobile to a vehicle body.

  An anti-vibration device interposed between a vehicle suspension mechanism and a vehicle body attenuates or reduces vibration transmitted from the road surface to the vehicle body. For example, a rubber-like elastic body with respect to the upper end of the piston rod And a vehicle body side mounting member that is coupled to the vehicle body panel via a vibration isolating base. Conventionally, in such an anti-vibration device, a steel member is generally used as the vehicle body side mounting member, but because there is a demand for measures to reduce the weight of parts for the purpose of reducing the energy consumption of the vehicle, A vibration isolator that has been reduced in weight by using an aluminum body-side mounting member has been proposed (see Patent Document 1 below).

The vehicle body side mounting member is fixed and assembled to the lower surface of the vehicle body panel by fastening members such as bolts and nuts around the mounting hole of the vehicle body panel. Therefore, a seal portion may be provided at a joint portion between the vehicle body side mounting member and the vehicle body panel (see Patent Document 2 below).
JP 2008-44452 A JP 2003-185025 A

  However, although there is a strong demand for reducing the energy consumption of vehicles and there is a demand for further weight reduction of the vibration isolator, the vibration isolator for connecting and supporting the suspension mechanism to the vehicle body side is strong and lightweight. It is not easy to achieve both.

  In addition, the sealing portion as described above is pressed against the entire periphery of the mounting hole of the vehicle body panel to ensure sufficient sealing performance. It is necessary to configure it with an elastic body such as rubber, and it has to be a separate member from the vehicle body side mounting member made of steel or aluminum, which leads to an increase in manufacturing man-hours.

  The present invention has been made in view of the above points, is lightweight and excellent in strength, and increases the number of manufacturing steps even when the joint portion between the vehicle body side mounting member and the vehicle body panel is sealed. An object of the present invention is to provide an anti-vibration device that can seal the joint without any problems.

A vibration isolator according to the present invention is disposed between a piston rod and a vehicle body panel of a shock absorber in a suspension mechanism of a vehicle, and is a vibration isolator for elastically coupling the piston rod to a vehicle body. A vehicle body side mounting member having an opening through which the piston rod penetrates, a rod upper mounting member disposed above the vehicle body side mounting member and fixed to the piston rod, and disposed below the vehicle body side mounting member. A lower rod mounting member fixed to the piston rod; an upper cushion rubber disposed between the vehicle body side mounting member and the rod upper mounting member in an annular shape through which the piston rod passes; and the piston rod A lower cushion rubber disposed between the vehicle body side mounting member and the rod lower side mounting member in a ring shape through which the upper side passes, and the upper side An upper holding member that holds the lower outer peripheral surface of the upper cushion rubber between the cushion rubber and the vehicle body side mounting member, and an upper outer periphery of the lower cushion rubber between the lower cushion rubber and the vehicle body side mounting member An anti-vibration device comprising: a lower holding member that holds a surface; and the vehicle body side mounting member is overlapped and disposed on a lower surface of the vehicle body panel in a state where the upper holding member is fitted in a mounting hole of the vehicle body panel The upper holding member and the lower holding member are made of a resin material or a rubber material and are formed integrally with the metal vehicle body side mounting member, and the upper holding member is spaced from the inner peripheral wall of the mounting hole. The abutment surfaces are opposed to each other, and the deformation is regulated by the abutment surfaces abutting against the inner peripheral wall of the mounting hole when the upper holding member is deformed radially outward .

  According to the said structure, since an upper side holding member and a lower side holding member are formed with a resin material or a rubber material, a vibration isolator can be reduced in weight compared with the case where it forms with metal materials, such as steel and aluminum. . Moreover, if the upper holding member is made of a resin material or rubber material that is lower in strength than a metal material, the thickness in the radial direction cannot be set to such an extent that sufficient rigidity can be obtained for the convenience of fitting into the mounting hole. However, even in such a case, the contact surface is in contact with the inner peripheral wall of the mounting hole, so that the deformation of the upper holding member in the radially outward direction is restricted. The upper holding member is not damaged due to excessive deformation.

  In the above-described vibration isolator, it is preferable that the upper holding member is provided with an annular seal portion that abuts the peripheral portion of the attachment hole and seals between the vehicle body side attachment member and the vehicle body panel. In addition, the seal portion includes two inner and outer annular step portions that are radially outwardly lowered, and the radial length of the inner annular step portion is longer than the radial length of the outer annular step portion. Is preferred. By adopting such a configuration, the seal portion can be formed integrally with the upper holding member, so that it is possible to seal between the vehicle body side mounting member and the vehicle body panel without increasing the number of manufacturing steps. In particular, when the radial length of the inner annular step is longer than the radial length of the outer annular step, a gap is formed between the upper holding member and the inner peripheral wall of the mounting hole, and the upper holding member is attached. It becomes easy to fit into the hole, and the assembly workability is improved.

  With the vibration isolator of the present invention, sufficient strength can be ensured while reducing the weight as the vibration isolator, and the joint between the vehicle body side mounting member and the vehicle body panel can be formed without increasing the number of manufacturing steps. Can be sealed.

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

  1 is a cross-sectional view of a vibration isolator 10 according to an embodiment of the present invention, FIG. 2 is a plan view of a vehicle body side mounting member 12 in which an upper holding member 34 and a lower holding member 35 are integrated, and FIGS. Is an enlarged view of the main part of FIG. 1, and FIG. 5 is a cross-sectional view taken along the line AA of FIG. The vibration isolator 10 is for elastically coupling the upper end of a piston rod of a shock absorber in a vehicle suspension mechanism to the vehicle body panel 2 and opens in the vertical direction Z so that the piston rod 1 penetrates. A vehicle body side mounting member 12 having a circular opening 13, a rod upper mounting member 14 and a rod lower mounting member 16 disposed above and below the vehicle body side mounting member 14, and the upper and lower mounting members 14, 16 and the vehicle body side mounting member 12. The upper cushion rubber 18 and the lower cushion rubber 20 disposed between the upper cushion rubber 18 and the lower cushion rubber 20, and the upper and lower holding members 34 and 35 that hold the outer peripheral surfaces of the upper and lower cushion rubbers 18 and 20.

  A mounting hole 4 for mounting the vibration isolator 10 is provided in the vehicle body panel 2. The mounting hole 4 is provided by bending upward from the vehicle body panel 2 in a cylindrical shape, and the cross-sectional shape of the lower peripheral edge of the mounting hole 4 is formed in a substantially arc shape that gradually expands outward. ing.

  The vehicle body side attachment member 12 is a plate-like member made of a metal such as aluminum or an aluminum alloy, and is fixed around the attachment hole 4 of the vehicle body panel 2 by bolts 25 and is superposed on the lower surface 2 a of the vehicle body panel 2. . The vehicle body side mounting member 12 includes a bolt hole 42 through which the bolt 25 is inserted and a base portion 40 in which the opening portion 13 is formed, and a bolt seat portion 44 provided around the bolt hole 42 and the opening portion 13 and thicker than the base portion 40. And an annular portion 46, and a reinforcing rib 48 provided between the bolt seat portion 44 and the annular portion 46.

  Specifically, the base 40 has a rhombus shape with rounded corners in plan view, and the opening 13 is provided at the center of the base 40, and the opening 13 is sandwiched between diagonal positions in the longitudinal direction of the base 40. A pair of bolt holes 42 are provided. The bolt seat portion 44 and the annular portion 46 are formed with inclined surfaces 50 and 52 at the boundary portion with the base portion 40, respectively, and stress applied from the bolt 25 and the piston rod 1 is locally concentrated on the boundary portion. It is prevented from acting, and the durability of the vehicle body side mounting member 12 is improved. The reinforcing rib 48 is a protrusion provided thicker than the base portion 40 extending from the bolt seat portion 44 to the annular portion 46, and a plurality of (this embodiment) is provided between the pair of left and right bolt seat portions 44 and the annular portion 46 in FIG. In the embodiment, three reinforcing ribs 48 are provided in parallel.

  Between the bolt seat portion 44 and the annular portion 46, an annular upper holding member 34 and a lower holding member 35 surrounding the opening portion 13 are disposed on the upper and lower surfaces of the base portion 40, respectively. A through hole 54 connecting the members 34 and 35 is formed in the base 40.

  The rod upper mounting member 14 is a circular plate-shaped member made of metal, and is disposed in contact with the upper surface of the upper cushion rubber 18. The rod upper mounting member 14 includes an insertion hole 22 through which the piston rod 1 is inserted, and is configured to be fixed to the piston rod 1 by tightening the piston rod 1 with a nut 3.

  The rod lower mounting member 16 is a circular plate-shaped member made of metal, and is disposed in contact with the lower surface of the lower cushion rubber 20. The rod lower mounting member 16 includes an insertion hole 24 through which the piston rod 1 is inserted in the center, and is configured to be fixed to the piston rod 1 by tightening with the nut 3. The rod lower mounting member 16 is connected to the rod upper mounting member 14 via a cylindrical sleeve 15 disposed coaxially with the insertion holes 22 and 24, and the rod upper mounting member 14 and the rod lower mounting member 16 are connected to each other. The interval is specified.

  The upper cushion rubber 18 is an annular rubber-like member provided with a hollow portion 18a through which the piston rod 1 passes, and is disposed coaxially with the opening 13 so that the vehicle body side mounting member 12 and the rod upper mounting member 14 Are assembled in a state compressed in the axial direction A (that is, the vertical direction Z). The hollow portion 18a of the upper cushion rubber 18 is formed in a wide-mouth shape in which the inner diameter of the upper opening end portion 19 is larger than that of the other portion, and thereby the opening end portion 19 of the hollow portion 18a during compression in the axial direction A. It is possible to reduce the friction with the piston rod 1 and to suppress the occurrence of cracks at the opening end 19. A cylindrical rubber portion 18 c protruding in the axial direction A is integrally provided on the lower surface 18 b of the upper cushion rubber 18. The cylindrical rubber portion 18 c extends in the axial direction from the opening edge of the hollow portion 18 a of the upper cushion rubber 18, and the outer periphery of the piston rod 1 is between the opening 13 of the vehicle body side mounting member 12 and the sleeve 15. Is configured to surround.

  The lower cushion rubber 20 is an annular rubber-like member having a hollow portion 20a through which the piston rod 1 passes, and is disposed coaxially with the opening 13 so that the vehicle body side mounting member 12 and the rod lower side mounting member are disposed. 16 in a compressed state in the axial direction A. The hollow portion 20a of the lower cushion rubber 20 is formed in a wide mouth shape in which the inner diameter of the lower opening end portion 21 is larger than that of the other portion, and thereby the opening end portion of the hollow portion 20a during compression in the axial direction A. The friction with the piston rod 1 at 21 can be reduced, and the occurrence of cracks at the open end 21 can be suppressed. A cylindrical rubber portion 20 c protruding in the axial direction A is integrally provided on the upper surface 20 b of the lower cushion rubber 20. The cylindrical rubber portion 20 c extends in the axial direction from the opening edge of the hollow portion 20 a of the lower cushion rubber 20, and between the opening 13 of the vehicle body side mounting member 12 and the sleeve 15, the piston rod 1. It is comprised so that the outer periphery may be surrounded.

  A stopper rubber 39 extending outward is provided in an annular shape on the outer peripheral surface of the lower cushion rubber 20. The stopper rubber 39 is in contact with the lower surface of the lower holding member 35 at a predetermined interval from the upper surface of the rod lower mounting member 16, and when the piston rod 1 is displaced upward (bound side displacement), the rod lower mounting member. 16 is prevented from coming into direct contact with the lower holding member 35, and abnormal noise and impact are suppressed.

  The upper holding member 34 is made of a resin material or a rubber material harder than the upper cushion rubber 18 and the lower cushion rubber 20, and is, for example, rubber hardness (rubber hardness measured according to JISK6253 durometer hardness test (type A)). Hereinafter, the same) is a member that is made of 80 or more rubber materials and that is integrally disposed on the vehicle body side mounting member 12 by receiving the upper cushion rubber 18.

  The upper holding member 34 is an annular member that is disposed so as to surround the outside of the annular portion 46 and protrudes upward from the upper surface of the vehicle body side attachment member 12. The inner peripheral surface of the upper holding member 34 is formed in a tapered shape that narrows downward, and holds the lower outer peripheral surface 18 e of the upper cushion rubber 18. The outer peripheral surface of the upper holding member 34 extends substantially vertically upward with respect to the vehicle body side mounting member 12 and abuts against the inner peripheral wall 4a of the mounting hole 4 when the upper holding member 34 is deformed radially outward. 36. In addition, the outer peripheral surface of the upper holding member 34 includes a curved surface 38 having a substantially arc-shaped cross section that continuously extends below the contact surface 36 and gradually outwards, and is provided on the outer periphery of the base portion of the upper holding member 34. An annular seal portion 37 is formed at the lower end portion of the corresponding curved surface 38.

  The upper holding member 34 is fitted into the mounting hole 4 so that the contact surface 36 faces the inner peripheral wall 4a of the mounting hole 4 with a predetermined interval L in the assembled state to the vehicle, and the seal portion 37 is mounted on the mounting hole. 4, the space between the vehicle body side mounting member 12 and the vehicle body panel 2 is sealed.

  That is, as shown in FIG. 3, the seal portion 37 includes two inner and outer annular step portions 37 a and 37 b that are radially outwardly lowered, and the cross-sectional shape has an arc shape that gradually spreads outward toward the lower side. By being pressed against the lower peripheral edge portion of the mounting hole 4 formed, the seal portion 37 is sandwiched between the vehicle body side mounting member 12 and the vehicle body panel 2 in the vertical direction to perform sealing. The radial length a of the annular step 37a on the inner side of the seal portion 37 is longer than the radial length b of the outer annular step 37b. As described above, by setting the radial length a of the inner annular step portion 37a to be long, it is easy to form the gap S of the predetermined interval L between the inner peripheral wall 4a and the contact surface 36.

  By receiving the upper cushion rubber 18 whose inner peripheral surface of the upper holding member 34 is compressed downward by the downward displacement (rebound side displacement) of the piston rod 1 and expands and deforms radially outward, the expansion deformation is limited. It is a member for obtaining desired spring characteristics in the rebound side displacement.

  The contact surface 36 contacts the inner peripheral wall 4a of the mounting hole 4 when the upper holding member 34 expands and deforms outward in the radial direction. That is, when the displacement of the piston rod 1 on the rebound side is large and the amount of deformation of the upper cushion rubber 18 in the radially outward direction is increased, the upper holding member 34 may also be expanded and deformed radially outward due to the deformation of the upper cushion rubber 18. However, in such a case, as shown in FIG. 4, the abutment surface 36 collapses a predetermined distance L formed between the inner peripheral wall 4a and abuts against the inner peripheral wall 4a to radially outward the upper holding member 34. Limit expansion deformation to.

  The lower holding member 35 is an annular member that is disposed so as to surround the outside of the annular portion 46 and protrudes downward from the lower surface of the vehicle body side mounting member 12, and is harder than the upper cushion rubber 18 and the lower cushion rubber 20. For example, it is made of a rubber material having a rubber hardness of 80 or more, and is a member that receives the upper surface of the lower cushion rubber 20 and is integrally disposed on the vehicle body side mounting member 12. . The inner peripheral surface of the lower holding member 35 is formed in a tapered shape that becomes narrower upward, and holds the upper outer peripheral surface 20 e of the lower cushion rubber 20. The lower holding member 35 may be provided with a radial thickness larger than that of the upper holding member 34, and the upper holding member 35 is moved upward by the bound side displacement of the piston rod 1 above the inner peripheral surface of the lower holding member 35. It becomes easy to set the thickness to such an extent that the lower cushion rubber 20 that is compressed and expanded and deformed radially outward can be received.

  Further, as shown in FIG. 5, the base portion 40 excluding the bolt seat portion 44 and the annular portion 46 is covered with a resin material or a rubber material constituting the upper and lower holding members 34, 35, whereby the upper and lower holding members 34, 35 are integrally connected to each other through a covering portion 41 covering the base portion 40 and a through hole 54 formed in the vehicle body side mounting member 12.

  In the vibration isolator 10 of the present embodiment configured as described above, since the upper holding member 34 and the lower holding member 35 are formed of a resin material or a rubber material, the anti-vibration device 10 is more resistant than a conventional case of a metal material. The vibration device 10 can be reduced in weight.

  In addition, when the vibration isolator 10 is assembled to the vehicle, there is a predetermined distance L between the contact surface 36 and the inner peripheral wall 4a, so that the upper holding member 34 can be easily fitted into the mounting hole 4. In addition, when the upper holding member 34 is expanded and deformed outward in the radial direction, the contact surface 36 contacts the inner peripheral wall 4a of the mounting hole 4, so that the rigidity is inferior to that of the metal material. Even when a resin material or a rubber material is used for the upper holding member 34, the upper holding member 34 is not excessively deformed and is not damaged.

  In addition, since the upper holding member 34 and the lower holding member 35 are connected to each other via the covering portion 41 that covers the base portion 40 and the through hole 54 formed in the vehicle body side mounting member 12, the vehicle body side mounting member The upper holding member 34 and the lower holding member 35 can be easily formed on the upper and lower surfaces, respectively, and can be firmly integrated with the vehicle body side mounting member 12.

  Further, since the upper holding member 34 is made of a resin material or a rubber material, even when the upper holding member 34 is provided with a seal portion 37 that seals between the vehicle body side mounting member 12 and the vehicle body panel 2, The seal portion 37 can be integrally formed simultaneously with the molding of the upper holding member 34. Therefore, it is not necessary to form the seal portion 37 or install the seal portion 37 on the upper holding member 34, and the space between the vehicle body side mounting member and the vehicle body panel can be sealed without increasing the number of manufacturing steps.

  In addition, although this embodiment demonstrated the case where the vehicle body side attachment member 12 was formed with aluminum or aluminum alloy, you may form with other metals, such as steel materials.

  FIGS. 6 to 9 show a modified example of the vehicle body side mounting member 12 in the above embodiment. In this example, when the vehicle body side mounting member 12 is formed of a high-strength material such as steel, the thickness is substantially constant. Reinforcing reinforcing ribs 47 and 49 are formed by bending the outer peripheral end portion of the base portion 40 made of the plate member and the inner peripheral end portion of the opening portion 13. The base portion 40 is covered with a resin material or a rubber material constituting the upper and lower holding members 34 and 35 except for a portion contacting the lower surface side of the bolt seat portion 44 and the lower surface 2a of the vehicle body panel 2, and a covering portion 41 is formed. The upper and lower holding members 34 and 35 are integrally connected to each other through the covering portion 41 and the through hole 54. In such a case, the bolt hole 42, the opening 13 and the reinforcing ribs 47 and 49 can be formed at a time by pressing or the like, and the number of manufacturing steps can be reduced and the cost can be reduced.

  The present invention can be used mainly for a suspension mechanism of a vehicle such as an automobile.

It is sectional drawing of the vibration isolator which concerns on one Embodiment of this invention. It is a top view of the vehicle body side attachment member with which the upper side holding member and the lower side holding member were integrated. It is a principal part enlarged view of FIG. 1, Comprising: The upper side holding member shows the state before a deformation | transformation to radial direction outward. It is a principal part enlarged view of FIG. 1, Comprising: The upper side holding member shows the state which deform | transformed to radial direction outward. It is AA sectional drawing of FIG. It is sectional drawing of the vibration isolator which concerns on the example of a change of this invention. It is a top view of the vehicle body side attachment member in which the upper side holding member and the lower side holding member in the vibration isolator which concerns on the example of a change of this invention were integrated. It is BB sectional drawing of FIG. It is CC sectional drawing of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Piston rod 2 ... Vehicle body panel 2a ... Lower surface 4 ... Mounting hole 10 ... Vibration isolator 12 ... Vehicle body side mounting member 13 ... Opening part 14 ... Rod upper side mounting member 16 ... Rod lower side mounting member 18 ... Upper cushion rubber 20 ... Lower cushion rubber 25 ... bolt 34 ... upper holding member 35 ... lower holding member 36 ... contact surface 37 ... seal portion

Claims (3)

A vibration isolator arranged between a piston rod and a vehicle body panel of a shock absorber in a vehicle suspension mechanism, and elastically coupling the piston rod to a vehicle body,
A vehicle body side mounting member having an opening through which the piston rod passes, a rod upper mounting member disposed above the vehicle body side mounting member and fixed to the piston rod, and disposed below the vehicle body side mounting member. A lower rod mounting member fixed to the piston rod, an upper cushion rubber disposed between the vehicle body side mounting member and the rod upper mounting member in an annular shape through which the piston rod passes, and the piston rod A lower cushion rubber disposed between the vehicle body side mounting member and the rod lower mounting member in an annular shape penetrating; and the upper cushion rubber between the upper cushion rubber and the vehicle body side mounting member. An upper holding member that holds the lower outer peripheral surface, and an upper outer peripheral surface of the lower cushion rubber is maintained between the lower cushion rubber and the vehicle body mounting member. In the vibration damping device and a lower retaining member, wherein the upper retaining member is the body side mounting member fitted state into the mounting hole of the vehicle body panel is polymerized disposed on the lower surface of the vehicle body panel,
The upper holding member and the lower holding member are made of a resin material or a rubber material, and are molded integrally with the metal body-side mounting member,
The upper holding member is provided with a contact surface facing the inner peripheral wall of the mounting hole with a gap, and the contact surface contacts the inner peripheral wall of the mounting hole when the upper holding member is deformed radially outward. The vibration isolator is characterized in that the deformation is restricted by contact .   2. The prevention according to claim 1, wherein the upper holding member is provided with an annular seal portion that comes into contact with a peripheral edge portion of the attachment hole and seals between the vehicle body side attachment member and the vehicle body panel. Shaker. The seal portion includes an inner and outer two-stage annular step portion that is lowered radially outward,
The vibration isolator according to claim 2, wherein a radial length of the inner annular step portion is longer than a radial length of the outer annular step portion.

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