JP2010270873A - Vibration damping device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vibration damping device for absorbing an impact in the axial direction while regulating displacement. <P>SOLUTION: Since an outer cylinder 14 is elastically supported by plate members 38 and 40 fastened by a bolt 42 with a rubber elastic body 18, when input is generated between a bracket member 34 and the plate members 38 and 40, the impact and vibration are absorbed by the rubber elastic body 18. When the input in the axial direction further increases, a projection 25 arranged outside in the axial direction of the outer cylinder 14, contacts with the plate members 38 and 40, and then, a stopper 24 contacts with the plate members 38 and 40. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vibration isolator.

  In vehicles equipped with engines, construction machines, etc., the main places where vibrations are generated are caused by the engine, and rubber is mainly used for the purpose of preventing the vibration generated from the engine from being transmitted to passengers and workers. A configuration in which the engine is held on the frame by the vibration isolator is generally used.

  As an example, there is a vibration isolator using a vibration isolator to attach a vibration generating body such as an engine to a housing such as a vehicle for the purpose of not transmitting vibration from the engine to an operator (for example, see Patent Document 1).

  However, in the configuration as in Patent Document 1, when an external input is input to the vibration isolator, the mount itself is displaced, and there is a possibility that the holding position of the heavy engine is changed. In particular, since the displacement in the axial direction of the bolt that fastens the vibration isolator cannot be suppressed, the positional accuracy and durability may be impaired.

  For example, in the case of the vibration isolator as shown in FIG. 4, the outer cylinder 114 and the inner cylinder 116 are connected via the rubber elastic body 118, the bracket member 134 is sandwiched between the pair of outer cylinders 114, and the plate member 140. The rubber elastic body 118 absorbs vibration between the bracket member 134 and the plate member 140 by fastening the bolt 142 with the bolt 142. However, the input in the axial direction, that is, the surface direction of the plate member 140 and the bracket member 134 is excessive. As a result, the amount of displacement of the inner cylinder 116 with respect to the outer cylinder 114 increases, and the positional accuracy of the plate member 140 and the bracket member 134 may not be maintained.

  Concerning the above problems, it is conceivable that the engine is supported by anti-vibration rubber or the like, and the displacement is restricted by a high-strength / hard member such as metal against relatively large external input / displacement. A large impact acceleration is instantaneously generated by contact. This may cause problems such as strength problems and looseness of the engine, the fuselage frame, bolts and nuts used for mounting, and may have an effect on members that are less resistant to impact.

  Therefore, in order to reduce the impact caused by the collision between the axially outer end of the outer cylinder and the plate member when an excessive input in the compression direction occurs, there is a vibration isolator provided with a stopper rubber on the outer cylinder (for example, , See Patent Document 2).

  However, in the configuration as described in Patent Document 2, the mechanism becomes complicated and the number of parts increases, so that the cost of parts is affected, and it is necessary to assemble a stopper rubber formed separately, which may increase the number of production steps. .

  Further, the direction, frequency, and degree of external input are difficult to specify, and displacement regulation in various directions is required. For this reason, sandwiched mounts are used exclusively in construction machines such as hydraulic excavators as a structure that prevents the supported members such as engines from falling off even if the anti-vibration rubber breaks, but this structure has high support rigidity. If the idling speed is set low, vibrations may not be completely absorbed, so that both sufficient strength and low support rigidity are required.

  Further, in order to satisfy the evaluation values such as buffering property, fastening strength, looseness, etc. with respect to the setting of the stopper, it is necessary to set dimensions in sub-millimeter units according to the equipment and usage conditions. When realizing the configuration described in the conventional example as a rubber part manufactured by a mold, it is impossible to share the mold, so that time and cost for remodeling the mold are required.

JP 2004-301196 A JP 2006-300106 A

  In view of the above facts, an object of the present invention is to provide a vibration isolator that absorbs an axial impact and restricts displacement.

  The vibration isolator according to claim 1 is connected to one of the vibration generating portion and the vibration receiving portion via a bracket member, and is provided on the outer side in the circumferential direction at a cylindrical tube portion and an axially outer end portion of the tube portion. A substantially cylindrical outer cylinder having a flange portion extending to the other, and a substantially cylindrical outer cylinder connected to the other of the vibration generating portion and the vibration receiving portion via a plate member and coaxially disposed on the inner peripheral side of the cylindrical portion. A cylindrical inner cylinder, a pair of vibration isolating bodies made of an elastic body disposed between the outer peripheral surface of the outer cylinder and the flange portion, and the outer peripheral surface of the inner cylinder, and the radial direction of the flange portion A stopper formed by folding the outer peripheral end outward in the axial direction, and a protrusion made of an elastic body provided radially at the inner side of at least one of the stoppers and extending outward in the axial direction from the stopper. It is characterized by that.

  In the invention with the above configuration, before the stopper restricts the axial displacement of the vibration isolator with respect to the input in the axial direction, the elastic body extending outward in the axial direction from the stopper absorbs the displacement and performs buffering. After that, the stopper restricts the displacement, so that it is possible to absorb the impact in the axial direction, restrict the displacement amount, and improve the durability.

  The vibration isolator according to claim 2 is the configuration according to claim 1, wherein the elastic body of the vibration isolator provided on the load load side of the bracket member extends to the radially inner side of the stopper. It is characterized by that.

  In the invention having the above-described configuration, it is possible to efficiently absorb an impact with a plate member on the load load side where a bracket member on which a heavy object such as an engine is suspended is likely to collide.

  Since the present invention has the above-described configuration, it is possible to provide a vibration isolator that absorbs an axial impact and restricts displacement.

It is sectional drawing which shows the structure and assembly method of the vibration isolator which concerns on embodiment of this invention. It is a perspective view which shows the structure of the vibration isolator shown in FIG. It is a graph which shows the effect of the present invention. It is sectional drawing which shows the structure of the conventional vibration isolator.

<Example>
Hereinafter, the present invention will be described in more detail with reference to examples.

  FIG. 1 shows a vibration isolator according to an embodiment of the present invention. The vibration isolator 10 is applied, for example, as an engine mount in a vehicle, and attenuates and absorbs input from an engine that is a vibration generating unit, and reduces vibrations that are input to a vehicle body that is a vibration receiving unit.

  The anti-vibration device 10 includes a pair of anti-vibration bodies 12 having the same structure and shape, and the pair of anti-vibration bodies 12 are disposed so as to have a symmetrical positional relationship along the axial direction. Has been.

  The vibration isolator 12 includes a metal outer cylinder 14 formed in a substantially cylindrical shape, a metal inner cylinder 16 formed in a cylindrical shape and disposed substantially coaxially on the inner peripheral side of the outer cylinder 14, A rubber elastic body 18 disposed between the outer cylinder 14 and the inner cylinder 16 is provided.

  The outer cylinder 14 is provided with a cylindrical portion 20 formed in a cylindrical shape in the axial direction on the inner peripheral side, and an annular flange portion extending radially outward from the axially outer end portion of the cylindrical portion 20. 22 is integrally formed.

  The radially outer end of the flange portion 22 is folded outward in the axial direction, and a stopper 24 is formed. That is, a cylindrical stopper 24 is formed coaxially with the cylindrical portion 20, and the flange portion 22 is connected between the two.

  The inner cylinder 16 is formed in a cylindrical shape that is longer than the outer cylinder 14 along the axial direction, and is supported by the rubber elastic body 18 so that the outer end protrudes outward in the axial direction from the inside of the cylindrical portion 20. . Further, as shown in FIG. 1A, the inner cylinder 16 is in a position in which the end portion on the inner side in the axial direction is retracted from the inner end portion of the cylinder portion 20 in a state before the vibration isolator 12 is assembled. Yes, when the inner cylinder 16 is pushed inward in the axial direction by the pressing force from the outside in the axial direction, it is abutted against the inner end in the axial direction of the inner cylinder 16 of the vibration isolator 12 that makes a pair.

  The rubber elastic body 18 is formed in a substantially thick cylindrical shape, and the entire inner peripheral surface thereof is fixed to the outer peripheral surface of the inner cylinder 16 by vulcanization adhesion, and is also vulcanized and bonded to the inner peripheral surface of the outer cylinder 14. And is fixed to the outer cylinder 14. Accordingly, the inner cylinder 16 is elastically connected and supported in the axial direction and the radial direction by the rubber elastic body 18 with respect to the outer cylinder 14.

  The rubber elastic body 18 is formed with a recess 28 that is recessed in the axial direction on the end surface in the axial direction along the circumferential direction. The rubber elastic body 18 is formed with a groove portion 26 having a substantially V-shaped cross section along the outer peripheral surface of the inner cylinder 16 on the end surface on the outer side in the axial direction, and a portion having a lower rigidity than the periphery. Is configured.

  The rubber elastic body 18 has a substantially tapered cross section in which the axial thickness gradually decreases from the radially inner side to the radially outer side, and the axially outer end surface is changed from the inner peripheral side to the outer peripheral side. The inclined surface 29 is inclined toward the inner side in the axial direction (the lower side in the drawing in FIG. 1A).

  Further, a rubber elastic body 18 extends from the flange portion 22 of the outer cylinder 14 to an inner peripheral surface that is radially inward of the stopper 24, and the rubber elastic body 18 extends outward in the axial direction on the inner peripheral surface of the stopper 24. . That is, a protrusion 25 of the rubber elastic body 18 is formed from the flange portion 22 through the radially inner side of the stopper 24 and continuing outward in the axial direction. The axially outer end of the protrusion 25 protrudes in the axial direction from the stopper 24.

  Here, the rubber elastic body 18 is formed using a rubber material such as NR or NBR as a raw material. The rubber elastic body 18 is, for example, vulcanized (molded) with the inner cylinder 16 as an insert core, and vulcanized and bonded to the outer peripheral surface of the inner cylinder 16 and the inner peripheral surface of the outer cylinder 14 simultaneously with the vulcanization molding. It is fixed by.

  As shown in FIGS. 1 (A) and 1 (B), the pair of vibration isolator 12 holds the bracket member 34 between the pair of flange portions 22 while the inner ends of the inner cylinder 16 face each other. To do. At the same time, the pair of vibration isolator 12 is held between the pair of plate members 38 and 40 from the outside in the axial direction.

  Here, the bracket member 34 is connected to the engine side of the vehicle, for example, and the bracket member 34 has a circular opening having an inner diameter corresponding to the outer diameter of the outer cylinder 14 at a connection portion with the vibration isolator 10. 35 (see FIG. 1A and FIG. 2) is drilled.

  When the bracket member 34 is sandwiched between the pair of flange portions 22, the cylindrical portions 20 that are the inner ends of the pair of outer cylinders 14 are inserted into the openings 35 of the bracket members 34 from the outside in the axial direction, respectively. The peripheral portion of the opening 35 is clamped from both sides of the bracket member 34 by the flange portion 22 of the outer cylinder 14.

  As shown in FIG. 1, an insertion hole 39 penetrating in the axial direction is formed in the plate member 38 arranged on the outer side in the axial direction of the vibration isolator 12 on one side (lower side in FIG. 1A). Has been. Further, an insertion hole 41 penetrating in the axial direction is also formed in the plate member 40 disposed on the outer side in the axial direction of the vibration isolator 12 on the other side (upper side in FIG. 1A). At this time, at least one of the plate members 38 and 40 is connected to the vehicle body side. When the vibration isolator 10 is assembled, the plate member 38, the plate member 40, and the pair of vibration isolators so that the insertion hole 39 and the insertion hole 41 coincide with the openings of the pair of inner cylinders 16 on the same axis. 12 are respectively adjusted in position.

  When the vibration isolator 10 is assembled, the bolts 42 are inserted from the axially outer side in the order of the insertion holes 41 of the plate member 40, the inner peripheral side of the pair of inner cylinders 16, and the insertion holes 39 of the plate member 38. A nut 46 is screwed into the tip of the bolt 42 protruding from the insertion hole 39 via a washer 44.

  At this time, the nut 46 is screwed into the bolt 42 until the pair of inner cylinders 16 are brought into a state where the inner surfaces in the axial direction are pressed against each other. Accordingly, the pair of vibration isolator 12 fixes the plate members 38 and 40 to the rigid with the pair of inner cylinders 16, and the outer cylinder 14 holding the bracket member 34 elastically supports the inner cylinder 16 with the rubber elastic body 18. Therefore, the bracket member 34 is elastically supported by the pair of rubber elastic bodies 18 with respect to the plate members 38 and 40.

  As shown in FIG. 1B, since the outer cylinder 14 is elastically supported by the rubber elastic body 18 on the plate members 38 and 40 fastened by the bolts 42, the space between the bracket member 34 and the plate members 38 and 40. When an input is generated, impact, vibration, etc. are absorbed by the rubber elastic body 18. Further, when the input in the axial direction increases, the projection 25 provided on the outer side in the axial direction of the outer cylinder 14 comes into contact with the plate members 38 and 40, and then the stopper 24 comes into contact with the plate members 38 and 40.

  That is, there is an excessive input between the plate members 38 and 40 and the bracket member 34, and when the rubber elastic body 18 is displaced in the axial direction, the projection 25 first comes into contact with the plate members 38 and 40 to reduce the impact. The input is absorbed up to the limit of the displacement amount of the protrusion 25. Next, the stopper 24 provided on the outer periphery (radially outer end) of the flange portion 22 suppresses excessive displacement of the rubber elastic body 18 and maintains the positional accuracy of the plate members 38 and 40 and the bracket member 34.

<Effect>
Since this invention was set as the said structure, it has the following outstanding effects.

  That is, as shown in FIG. 4, in the conventional configuration not provided with the protrusion 25, the amount of displacement of the rubber elastic body 118 increases with respect to the load input between the plate members 138 and 140 and the bracket member 134, and bending is performed. Since the stopper 124, which is the leading end of the flange portion, comes into contact with the plate members 138 and 140, members such as metal having no elasticity collide with each other, and there is a possibility that an impact may occur.

  On the other hand, in the embodiment of the present invention shown in FIGS. 1 and 2, the rubber elastic body 18 is first displaced with respect to the load input between the plate members 38 and 40 and the bracket member 34. However, before the stopper 24 comes into contact with the plate members 38 and 40, the projection 25 first comes into contact with the plate members 38 and 40 to absorb the impact, and when the input becomes larger, the stopper 24 stops. When 24 contacts the plate members 38 and 40, the distance between the plate members 38 and 40 and the bracket member 34 is maintained.

  That is, as shown by a dotted line in FIG. 3, in the conventional configuration that does not include the protrusion 25, the rubber elastic body 118 is applied to the load (vertical axis) input between the plate members 138 and 140 and the bracket member 134. When the amount of displacement increases and the stopper 124 comes into contact with the plate members 138 and 140, the stopper 124 functions as a position regulating member, and the amount of displacement does not increase from the value of the broken line d in the figure. That is, even if the load input between the plate members 138 and 140 and the bracket member 134 increases, no further displacement occurs. For this reason, there is a problem that an impact occurs when the stopper 124 contacts the plate members 138 and 140.

  On the other hand, as shown by the solid line in the figure, in the embodiment of the present invention, the amount of displacement of the rubber elastic body 18 increases with respect to the load input between the plate members 38 and 40 and the bracket member 34. Since the repulsive force increases once when the projection 25 comes into contact with the plate members 38, 40, the load can be absorbed without generating an impact.

  If the input further increases, the stopper 24 comes into contact with the plate members 38 and 40 due to the deformation of the projection 25, and further displacement can be suppressed, and the positional accuracy of the plate members 38 and 40 and the bracket member 34 is maintained. And durability is improved.

<Second Embodiment>
When the pair of vibration isolator 12 sandwiches the bracket member 34 from, for example, a substantially vertical direction, when a heavy load such as an engine is applied to the bracket member 34, the vibration isolator 12 is provided on the load load side of the bracket member 34. Further, a load is applied to the rubber elastic body 18 of the vibration isolator 12 in a direction in which it is always compressed.

  Therefore, the distance between the stopper 24 of the vibration isolator 12 provided on the lower side of the bracket member 34 and the plate member 38 is smaller than the distance between the stopper 24 of the vibration isolator 12 provided on the upper side and the plate member 40. For this reason, when the vibration or the like is input to the bracket member 34, the stopper 24 of the vibration isolator 12 on the load side easily comes into contact with the plate member 38.

  Therefore, in this embodiment, the protrusion 25 is provided on the vibration isolator 12 provided on the lower side of the bracket member 34.

  Since the protrusion 25 is provided on the vibration isolator 12 only on the lower side of the bracket member 34 as described above, the shock is effectively applied to the vibration isolator 12 where the load is greater and the plate member 38 and the stopper 24 are easily in contact with each other. It can be set as the structure which absorbs.

  Thereby, since it is not necessary to provide the protrusion 25 in each of a pair of vibration isolator 12, it can be set as the vibration isolator of simple structure at lower cost.

<Summary>
As mentioned above, although the Example of this invention was described, it cannot be overemphasized that this invention is not limited to said Example at all, and can implement in a various aspect in the range which does not deviate from the summary of this invention.

  For example, in each of the above-described embodiments, the stopper 24 or the protrusion 25 having the same shape is provided on both the pair of vibration isolator 12, but the present invention is not limited to this. The shapes may be different.

  The present invention can also be applied to applications other than engine mounts. That is, the present invention can be applied to various uses such as a cabin mount as long as it is intended to fix a supported member that generates vibration or a supported member to be protected from vibration to a frame or the like.

DESCRIPTION OF SYMBOLS 10 Vibration isolator 12 Vibration isolator 14 Outer cylinder 16 Inner cylinder 18 Rubber elastic body 20 Cylinder part 22 Flange part 24 Stopper 34 Bracket member 35 Opening part 38 Plate member 40 Plate member 50 Protrusion

Claims (2)

A cylindrical tubular portion connected to one of the vibration generating portion and the vibration receiving portion via a bracket member, and a flange portion extending outward in the circumferential direction at an axially outer end portion of the tubular portion. A substantially cylindrical outer cylinder;
A substantially cylindrical inner cylinder connected to the other of the vibration generating part and the vibration receiving part via a plate member and coaxially arranged on the inner peripheral side of the cylindrical part;
A pair of vibration isolator made of an elastic body disposed between the outer peripheral surface of the outer cylinder and the flange portion and the outer peripheral surface of the inner cylinder;
A stopper formed by folding the radially outer peripheral end of the flange portion outward in the axial direction;
A protrusion formed of an elastic body provided on the radially inner side of at least one of the stoppers and extending outward in the axial direction from the stopper;
An anti-vibration device characterized by that. The vibration isolator according to claim 1, wherein the protrusion is provided on the vibration isolator provided on the load load side of the bracket member.

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