JP2010060031A - Fastening mechanism and anti-vibration device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fastening mechanism that uses elastic members, having the same load characteristics, without increase in the size, as well as, preventing the limitation of the range of use from being caused in a load curve, and also suppresses the transmission of high-frequency vibrations, and to provide an anti-vibration device that uses the mechanism. <P>SOLUTION: The fastening mechanism 100, applied to an anti-vibration device, suppresses the transmission of vibrations between a bracket 101 and a vehicle body 102 by using springs 1, 2. A contact part 2A between the bracket 101 and the upper spring 2 is fixed, while a contact part 2B between the lower face of a large diameter part 104A of a bolt 104 and the upper spring 2 is fixed. The upper elastic member 2 is set so as to receive a vertical tensile load in the initial state, thereby allowing the upper elastic member 2 to receive the self weight of the bracket 101. The upper elastic member 2 is appropriately designed so as to allow the springs 1, 2 to receive the same load in the initial state. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a fastening mechanism for fixing a first member to a second member by a fixing jig in a state where elastic members are arranged on the upper and lower sides of the first member, and a vibration isolator using the fastening mechanism. Regarding improvement.

  In various fields such as the automobile industry, precision equipment industry, home appliances, and architecture, vibration isolators that suppress vibration transmission are used. Specifically, a vibration isolator provided between an object and a support is applied to an engine, a motor that rotates at high speed, a dewatering tank of a washing machine, a building, and the like. In the vibration isolator, it is effective to set the natural frequency of the system constituted by the object and the support part sufficiently lower than a predetermined frequency band. As a method for this, it is conceivable to reduce the spring constant of the support portion. In this case, if the spring constant is reduced, the spring must be enlarged in order to support the load.

  Therefore, a method of using a disc spring as an elastic member in the vibration isolator has been proposed. Since the load characteristic of the disc spring can be designed as shown by a curve shown in FIG. 9, it is possible to set a region A in which the load can be supported and the spring constant can be set small.

  A disc spring exhibiting such load characteristics is applied to a fastening mechanism for a vibration isolator as shown in FIG. 10 (for example, Patent Document 1). The fastening mechanism 200 includes a fixing jig 203 that fixes the first member 201 (object) to the second member 202 (support), and includes a lower disc spring 204 and an upper plate on the lower side and upper side of the first member 201. A spring 205 is arranged. In such a fastening mechanism 200, transmission of vibration generated between the first member 201 and the second member 202 is suppressed by the disc springs 204 and 205.

  However, in the initial state (attached state) of the fastening mechanism 200, the load on the lower disc spring 204 is the gravity Mg of the first member 201 (M is the mass of the first member, g is a gravity constant) and the fixing jig 203. Thus, the load on the upper disc spring 205 becomes the axial force F of the fixing jig 203, and the loads on the disc springs 204 and 205 are different. For this reason, when the disc springs having the same load characteristics are used as the disc springs 204 and 205, for example, if the lower disc spring 204 is set to be used in the region A having a small spring constant, the upper disc spring 205 has a spring constant of It will be used in a large area.

  Thus, in order to use the disc springs 204 and 205 in the region A, as shown in FIG. 11A, it is necessary to set the disc springs 204 and 205 to different load characteristics. The range of use of the spring had to be limited. In particular, as shown in FIG. 11B, when the gravity Mg of the first member 201 is very large with respect to the axial force F of the fixing jig 203, this problem becomes serious. Therefore, in order to set the disc springs 204 and 205 to the same load characteristic, it is conceivable to increase the axial force F of the fixing jig 203 to such an extent that the influence of the gravity Mg of the first member 201 can be ignored. In order to cope with this, the disc springs 204 and 205 must be enlarged.

  Further, when the disc springs 204 and 205 are deformed so that the shape thereof becomes substantially flat by applying a load, the inner peripheral edge and the outer peripheral edge of the disc springs 204 and 205 slide relative to the mating member. Friction. For this reason, when the use range of the disc springs 204 and 205 is set to the range of the region A in FIG. 9, the hysteresis shown in FIG. 12A occurs in the actual load curve. As a result, the substantial dynamic spring constant in the usage range of the disc springs 204 and 205 becomes the inclination of the diagonal line l connecting the point P and the point Q in FIG. In this case, when the amplitude of the use range is reduced, the slope of the diagonal line l increases as shown in FIG. 12B, and the dynamic spring constant increases. In the fastening mechanism to which the disc spring is applied in this manner, when a small amplitude vibration such as a high frequency vibration is input, the dynamic spring constant of the disc spring increases, so that the natural frequency of the system increases. There was a problem that transmission of high frequency vibrations could not be suppressed.

JP 2003-112533 A

  Therefore, according to the present invention, it is possible to use the elastic member having the same load characteristic without increasing the size, as well as preventing the use range from being limited in the load curve, and to prevent high frequency vibration. It aims at providing the fastening mechanism which can suppress transmission, and the vibration isolator using the same.

  The fastening mechanism of the present invention includes a fixing jig that fixes the first member and the second member, and an upper elastic member and a lower elastic member that are disposed on the upper side and the lower side of the first member. One of the second member and one end of the fixing jig is disposed on the upper side of the second elastic member, and the other of the one end of the second member and the fixing jig is disposed on the lower side of the lower elastic member. In the fastening mechanism that is disposed and maintains the held state of the first member by the upper elastic member and the lower elastic member by one end portion of the fixing jig, and fixes the other end portion of the fixing jig to the second member, The elastic member and the lower elastic member are made of metal, a contact portion between the upper elastic member and the member disposed on the upper and lower sides thereof, and the lower elastic member and the member disposed on the upper and lower sides thereof. At least the upper elastic member contact part is fixed It is characterized in that it is.

In the fastening mechanism of the present invention, of the contact portion between the upper elastic member and the member arranged on the upper and lower sides thereof, and the contact portion between the lower elastic member and the member arranged on the upper and lower sides thereof Since at least the contact portion of the upper elastic member is fixed, the upper elastic member can be set so as to receive a vertical tensile load in the initial state. Accordingly, since the upper elastic member can receive the weight of the first member, the upper elastic member and the lower elastic member are both disposed between them by appropriately designing the upper elastic member. Half of the weight of the member can be received. Further, in this case, since the axial force of the fixing jig can be set to zero, the upper elastic member and the lower elastic member can receive the same load in the initial state. Therefore, since the load characteristics exhibited by the elastic members can be matched without increasing the size of the upper elastic member and the lower elastic member, it is possible to prevent the use range from being restricted.

  As an elastic member that can fix the contact portion with the counterpart member, for example, the following spring can be used. That is, the elastic member includes a main body portion having a hole, a cylindrical portion provided in at least one of the inner peripheral portion and the outer peripheral portion of the main body portion, and a boundary portion between the main body portion and the cylindrical portion. A spring having a corner portion formed on the surface can be used. In this case, the main body portion of the spring extends in a direction intersecting the direction of the pressing force from the counterpart member positioned on the upper and lower sides of the spring, and the cylindrical portion of the spring extends from the peripheral portion of the main body portion to the upper and lower sides of the spring. It protrudes toward one of the mating members located on the side.

  In this case, since the corner is a part formed at the boundary between the main body portion and the cylindrical portion in the positional relationship as described above, such a corner portion changes its angle when a load is applied, It can move to the outside of the peripheral part provided with the cylindrical part in the extending direction of the main body part. In addition, the external side here is an inner peripheral part when the peripheral part provided with the cylindrical part is an inner peripheral part, and the peripheral part provided with the cylindrical part is an outer peripheral part. It is the outer side of the outer periphery.

  As described above, since the corner portion can be elastically deformed when a load is applied, by appropriately setting the distance between the corner portion and the mating member in the cylindrical portion, the vicinity of the mating member of the cylindrical portion can be obtained when the load is applied. The deformation of the part can be prevented. Thereby, since sliding with respect to the other member of a cylindrical part can be prevented, friction does not generate | occur | produce between a cylindrical part and an other party member, As a result, a hysteresis does not generate | occur | produce in the load characteristic of a spring. Therefore, the dynamic spring constant in the predetermined usage range of the spring that does not slide on the mating member is the slope of the tangent to the load curve at the center of the usage range (that is, the static spring constant). Even if the amplitude of the range is reduced, the slope of the tangent line does not change.

  Accordingly, since the dynamic spring constant does not increase, the natural frequency of the system can be reduced, and the vibration transmissibility of high-frequency vibration can be reduced. Also, with a spring that does not slide against the mating member, the dynamic spring constant does not depend on the dynamic friction coefficient of the mating member, so it is not necessary to check the dynamic spring constant according to the mating member when installing the spring. It does not take.

The fastening mechanism of the present invention can use various configurations. For example, if the natural frequency of the system including the first member, the second member, and the fastening mechanism is f ₀ , and the vibration frequency of any of the first member and the second member is f ₁ , Equation 1 It is preferable to satisfy. In this aspect, the vibration transmissibility of the high frequency vibration can be effectively reduced.

  The fastening mechanism of the present invention as described above can be applied to a vibration isolator.

  According to the fastening mechanism of the present invention or the vibration isolator using the same, it is possible to prevent the use range from being restricted, and to use an elastic member having the same load characteristics without increasing the size. In addition, it is possible to obtain an effect that transmission of high-frequency vibrations can be suppressed.

(1) Configuration of Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic sectional side view showing an installation state of a fastening mechanism 100 for a vibration isolator according to an embodiment of the present invention. The fastening mechanism 100 suppresses transmission of vibration generated between the bracket 101 (first member) and the vehicle body 102 (second member) by springs 1 and 2 (lower elastic member, upper elastic member). The bracket 101 is fixed to the vehicle body 102 by a bolt 104 (fixing jig). A vibration source 103 such as an engine or a propeller shaft is placed on the bracket 101. The fastening mechanism 100 includes springs 1 and 2, the lower spring 1 is disposed between the bracket 101 and the vehicle body 102, and the upper spring 2 is disposed between the large diameter portion 104 </ b> A of the bolt 104 and the bracket 101. Has been.

  The lower surface of the large diameter portion 104A of the bolt 104 is disposed at the upper end portion of the upper spring 2, and the small diameter portion 104B of the bolt 104 includes the hole 20A of the upper spring 2, the hole 101A of the bracket 101, and the hole of the lower spring 1. 10A is inserted. The contact portion 2A between the bracket 101 and the upper spring 2 is fixed, and the lower surface of the large diameter portion 104A of the bolt 104 and the contact portion 2B between the upper spring 2 are fixed. The contact portions 2A and 2B are fixed by mechanical fixing means, welding, or the like.

  The small diameter portion 104B of the bolt 104 is formed with a male screw, and the lower end thereof is screwed into a hole 102A in the vehicle body 102 in which the female screw is formed. In this case, the diameter of the small-diameter portion 104B of the bolt 104 is smaller than the diameter of the hole 20A of the upper spring 2, the diameter of the hole 101A of the bracket 101, and the diameter of the hole 10A of the lower spring 1. There is no contact.

  2A and 2B show the configuration of the lower spring 1, where FIG. 2A is a perspective view of the lower spring 1, and FIG. 2B is the right side portion of the lower spring 1 disposed between the bracket 101 and the vehicle body 102. It is sectional drawing. 3A and 3B show the configuration of the upper spring 2, wherein FIG. 3A is a perspective view of the upper spring 2, and FIG. 3B is a lower spring 1 disposed between the large diameter portion 104A of the bolt 104 and the bracket 101. It is a sectional side view of the right side part.

  The lower spring 1 is made of, for example, spring steel or reinforcing plastic as shown in FIG. The lower spring 1 includes, for example, a main body 10 having a hole 10A formed at the center. The main body 10 is, for example, a conical portion that extends in a direction that intersects the direction of the pressing force from the bracket 101 and the vehicle body 102. The conical part inclines downward as it goes from the inner peripheral part to the outer peripheral part, for example, and has a function as a disc spring.

  The hole 10A has, for example, a circular shape. A first cylindrical portion 11 (tubular portion) that protrudes toward the vehicle body 102 is provided on the inner peripheral portion of the main body portion 10. The upper end portion of the first cylindrical portion 11 is a contact portion that contacts the vehicle body 102. A second cylindrical portion 12 (cylindrical portion) that protrudes toward the bracket 101 is provided on the outer peripheral portion of the main body portion 10. The lower end portion of the second cylindrical portion 12 is a contact portion that contacts the bracket 101.

  A first corner 13 is formed at the boundary between the main body 10 and the first cylindrical portion 11, and a second corner 14 is formed at the boundary between the main body 10 and the second cylindrical portion 12. The first corner portion 13 and the second corner portion 14 can be elastically deformed so as to change the angle according to the pressing force from the bracket 101 and the vehicle body 102. When the 1st corner | angular part 13 and the 2nd corner | angular part 14 make circular arc shape, the curvature radius is made equal to the plate | board thickness of the main-body part 10 and the cylindrical parts 11 and 12, for example.

  The upper spring 2 includes a hole portion 10A, a first cylindrical portion, a hole portion 10A corresponding to the hole portion 10A, the first cylindrical portion 11, the second cylindrical portion 12, the first corner portion 13, and the second corner portion 14 of the lower spring 1. 21, a second cylindrical portion 22, a first corner portion 23, and a second corner portion 24. For example, as shown in FIG. 3, the upper spring 2 is different from the lower spring 1 in that the main body portion 20 that is a conical portion is inclined upward as it goes from the inner peripheral portion to the outer peripheral portion. Yes. In the upper spring 2, in the initial state (attached state), the upper spring 2 is set to receive a vertical tensile load when the main body portion 20 has the shape as described above.

  The first corner and the second corner of the springs 1 and 2 can be formed by various methods. For example, the first corner and the second corner can be formed by bending the boundary between the main body and the first cylindrical portion and the boundary between the main body and the second cylindrical portion. For example, it can form by welding of a main-body part and a 1st cylindrical part, and welding of a main-body part and a 2nd cylindrical part.

  The setting of the dynamic spring constants of the springs 1 and 2 will be described mainly with reference to FIGS. Since the springs 1 and 2 have the same dynamic spring constant setting, the spring 1 is used in the following description. 4 shows the operating state of the left side portion of the spring 1 of FIG. 1, (A) is a side sectional view before the operation of the spring 1 (dotted line) and at the time of operation (solid line), and (B) is the spring. FIG. 3 is an enlarged side cross-sectional view of a first corner portion 13 and a second corner portion 14 at the time of operation 1. 5A and 5B show load characteristics of the spring, wherein FIG. 5A is a load curve of a spring used in the fastening mechanism of the present invention (hereinafter referred to as a spring of the present invention), and FIG. 5B is a disc spring used in a conventional fastening mechanism. It is a load curve (hereinafter referred to as a conventional disc spring).

  As indicated by a dotted line in FIG. 4A, a downward load is applied from the bracket 101 to the spring 1 disposed between the bracket 101 and the vehicle body 102. Then, as shown by the solid line in FIG. 4B, the spring 1 is bent and the bracket 101 moves downward. Reference sign d in the figure indicates the amount of bending of the spring 1.

  Here, as shown in FIG. 4A, the main body portion 10 extends in a direction crossing the direction of the pressing force from the bracket 101, and on the upper side of the spring 1, the second cylindrical portion 12 is formed of the main body portion. 10 protrudes from the outer peripheral portion toward the bracket 101 and is in contact therewith. The second corner portion 14 formed at the boundary between the main body portion 10 and the second cylindrical portion 12 can be elastically deformed so that the angle α changes according to the pressing force from the vehicle body 102 when a load is applied. . In this case, since the second corner portion 14 is a portion formed at the boundary portion between the main body portion 10 and the second cylindrical portion 12 having the positional relationship as described above, the second corner portion 14 has a load. While changing the angle α at the time of application, it is possible to move to the outside (the left side in the figure) of the outer peripheral portion of the main body 10.

  Thus, since the second corner portion 14 can be elastically deformed when a load is applied, the second cylindrical portion 12 has an undeformed portion on the bracket 101 side when the load is applied (above the point S in FIG. 4B). By appropriately setting the length of the second cylindrical portion 12 so as to have it, partial deformation of the second cylindrical portion 12 on the bracket 101 side can be prevented.

  On the other hand, on the lower side of the spring 1, the first cylindrical portion 11 protrudes from the inner peripheral portion of the main body portion 10 toward the bracket 101 and is in contact therewith. In this case, the first corner portion 13 having the same function as that of the second corner portion 14 has an inner portion of the main body portion 10 while changing the angle β according to the pressing force from the bracket 101 during elastic deformation due to load application. It can move to the inside of the circumference (right side in the figure).

  Since the first corner portion 13 can be elastically deformed when a load is applied in this way, the first cylindrical portion 11 is not deformed on the vehicle body 102 side when the load is applied (below the point T in FIG. 4B). By appropriately setting the length of the first cylindrical portion 11 so as to have the above, partial deformation of the first cylindrical portion 11 on the vehicle body 102 side can be prevented.

  From the above, it is possible to prevent the first cylindrical portion 11 and the second cylindrical portion 12 from sliding, and therefore, between the first cylindrical portion 11 and the vehicle body 102 and between the second cylindrical portion 12 and the bracket 101. There is no friction.

  As shown in FIG. 5B, in the conventional disc spring that slides with the mating member, hysteresis occurs due to friction in the load curve. The spring constant is an inclination of a diagonal line n connecting the point U and the point V in FIG. In this case, when the amplitude of the use range A is reduced, the slope of the diagonal line n is increased, so that the dynamic spring constant is increased.

  On the other hand, in the spring of the present invention example that does not slide with the counterpart member as described above, hysteresis due to friction does not occur in the load curve as shown in FIG. As a result, the substantial dynamic spring constant in the usage range A of the spring 1 of the present invention that does not slide with the counterpart member is the slope of the tangent m to the load curve at the point R that is the center of the usage range (ie, Therefore, even when the amplitude of the use range A is reduced, the slope of the tangent m does not change, so the dynamic spring constant does not increase.

(2) The operation of the operation fastening mechanism 100 of the embodiment will be described mainly with reference to FIGS. FIG. 6 shows load characteristics of the spring used in the fastening mechanism of the present invention and the spring of the comparative example.

  In the fastening mechanism 100, since the sliding of the first cylindrical portion and the second cylindrical portion of the springs 1 and 2 can be prevented as described above, it is impossible to fix to the counterpart member because it slides with the counterpart member. Unlike the disc spring, the contact portion between the springs 1 and 2 and the mating member positioned on the upper and lower sides thereof can be fixed.

  Here, if both springs 1 and 2 are set to receive a compressive load in the initial state in the same manner as the disc spring, the load on the lower spring 1 is caused by the gravity Mg of the bracket 101 and the vibration source 103 (M is the vehicle body). And g is a gravitational constant) and the axial force F of the fixing jig 104, and the load on the upper spring 2 becomes the axial force F of the fixing jig 104. As described above, since the loads on the springs 1 and 2 differ by the weights of the bracket 101 and the vibration source 103, in order to use the springs 1 and 2 in a region where the spring constant is small, the springs 1 and 2 are different. Must be set to load characteristics. Specifically, as shown in FIG. 6 (B), the lower spring 1 must be set to the load characteristic indicated by the curve J, and the upper spring 2 must be set to the load characteristic indicated by the curve I.

  However, in this embodiment, the contact portion 2A between the bracket 101 and the upper spring 2 is fixed, and the lower surface of the large diameter portion 104A of the bolt 104 and the contact portion 2B between the upper spring 2 are fixed. The upper elastic member 2 can be set so as to receive a vertical tensile load in the state. Accordingly, since it is possible to receive the weight of the bracket 101 and the vibration source 103, the springs 1 and 2 are both designed by appropriately designing the upper spring 2 so that the weights of the bracket 101 and the vibration source 103 disposed therebetween are reduced. Half (= Mg / 2). In this case, since the axial force F of the fixing jig 104 can be set to zero, the springs 1 and 2 can receive the same load (= Mg / 2) in the initial state. Therefore, since the load characteristics shown by the springs 1 and 2 can be matched as shown by a curve H shown in FIG. 6A, the load curve shown in FIG. Thus, it is possible to prevent the use range A from being restricted.

  In particular, since the dynamic spring constant does not increase even when the operating range A is reduced as described above, the springs 1 and 2 can reduce the natural frequency of the system, as shown in FIG. The vibration transmissibility of vibration can be reduced. As a result, transmission of vibration from the bracket 101 to the vehicle body 102 by the vibration source 103 can be prevented by the lower spring 1. In addition, since the upper spring 2 is disposed between the large diameter portion 104A of the bolt 104 and the bracket 101, transmission of vibration from the bracket 101 to the vehicle body 102 through the bolt 104 can be prevented.

Here, when the natural frequency f ₀ of the system including the bracket 101, the vehicle body 102, and the fastening mechanism 100 is assumed, and the frequency of the target vibration is f ₁ , the natural frequency f ₀ of the system is shown in FIG. When the frequency f _b is matched with the frequency f _b shown, the frequency f ₁ of the vibration is in a region where the output is larger than the vibration input in the vibration characteristics of the system (curved line on the right side of the figure). There is a risk of being. Therefore, in this embodiment, to match the natural frequency f ₀ of the system to frequency f _a of FIG. 8. As a result, the frequency f ₁ of the vibration of interest is in a region where the output is smaller than the vibration input in the vibration characteristics of the system (solid curve on the left side of the figure), so that the vibration is attenuated. Therefore, when the natural frequency f ₀ of the system and the vibration frequency f ₁ satisfy the expression ₁ , the frequency f ₁ falls within a region where the vibration output is smaller than the input in the vibration characteristics of the system. Can be effectively prevented. Thus, it is preferable to satisfy Equation 1.

  Further, in the springs 1 and 2 that do not slide on the mating member, the dynamic spring constant does not depend on the dynamic friction coefficient of the mating member, so it is not necessary to check the dynamic spring constant according to the mating member when the springs 1 and 2 are installed. As a result, it takes less time. In particular, the dynamic spring constant can be adjusted as necessary by changing the fastening condition of the end of the small diameter portion 104B of the bolt 104 to the vehicle body 102.

(3) Modifications Although the present invention has been described with reference to the above-described embodiment, the present invention is not limited to the above-described embodiment, and various modifications are possible. In the following modification, the same components as those in the above embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  Various shapes can be used for the spring used in the fastening mechanism of the present invention. A slit can be formed in the main body portion and the cylindrical portion of the spring of the vibration isolator of the present invention for weight reduction. The main body of the present invention can have, for example, an S shape, a step shape, or a flat shape. The cylindrical portion may be cylindrical, and the side cross-sectional shape thereof may be a curved shape. Various shapes can be used for the bolt 104. For example, a stopper may be provided on the small diameter portion 104B in order to prevent the small diameter portion 104B from being screwed into the hole 102A excessively or insufficiently.

  In the above embodiment, the bolt 104 is used as the fixing jig. However, the bolt 104 is not limited to the bolt 104, and the bracket 101 is pressed toward the vehicle body 102 by one end and the other end is fixed to the vehicle 102. Anything that can do. In the springs 1 and 2, the first cylindrical portion and the second cylindrical portion are formed on the inner peripheral portion and the outer peripheral portion of the main body portion, but are formed only on one of the first cylindrical portion 11 and the second cylindrical portion 12. May be. Further, the shapes of the first corner and the second corner are not limited to the illustrated shapes, and can be changed to various shapes such as a curved shape. Moreover, in the said embodiment, although the contact part of the vehicle body 102 and the lower spring 1 and the contact part of the bracket 101 and the lower spring 1 were not fixed, those were fixed as needed, The lower spring 1 may be set to receive a tensile load.

  Furthermore, in the said embodiment, while arrange | positioning 104 A of large diameter parts of the volt | bolt 104 above the upper side spring 2, and arrange | positioning the vehicle body 102 below the lower side spring 1, it is not limited to this, Upper side spring The vehicle body 102 may be disposed on the upper side of the lower spring 2, and the large-diameter portion 104 </ b> A of the bolt 104 may be disposed on the lower side of the lower spring 1. In addition, the elastic member of the present invention is not limited to the springs 1 and 2 as long as it can be fixed to the mating member. For example, a coil spring can be used.

  The vibration isolator to which the fastening mechanism of the present invention is applied can use various auxiliary members for vibration isolation. For example, a damper material such as an elastomer elastic body can be arranged in parallel around the spring 1 between the bracket 101 and the vehicle body 102. In the spring 1, by preventing the vibration from being attenuated by preventing sliding with the counterpart member, the vibration is prevented from being transmitted, and the functional aspect of vibration isolation is strong. Therefore, in the said aspect, by using together the damper material which has a vibration suppression function, in addition to a vibration proof function, it can have a vibration suppression function, As a result, it can dampen early.

  Furthermore, in the above embodiment, an example in which the bracket 101 (first member) vibrates has been described. However, when the vehicle body 102 (second member) is vibrated, the same effect can be obtained by the same method as in the above embodiment. Needless to say, you can. Although the fastening mechanism of the present invention is applied to a vibration isolator, the present invention is not limited to this and can be applied to various devices. It goes without saying that the various modifications as described above can be appropriately combined.

It is a schematic sectional side view showing the installation state of the fastening mechanism for the vibration isolator which concerns on one Embodiment of this invention. The structure of the lower spring which concerns on one Embodiment of this invention is represented, (A) is a perspective view of a lower spring, (B) is a sectional side view of the right side part of the lower spring arrange | positioned between members. . The structure of the upper side spring which concerns on one Embodiment of this invention is represented, (A) is a perspective view of an upper side spring, (B) is a sectional side view of the right side part of the upper side spring arrange | positioned between members. 1 represents the operating state of the left side portion of the lower spring in FIG. 1, (A) is a side sectional view before the spring operation (dotted line) and during operation (solid line), and (B) is the operating state of the spring. It is an expanded side sectional view of the 1st corner and the 2nd corner. The load characteristic of a spring is represented, (A) is the load curve of the spring used for the fastening mechanism of this invention, (B) is the load curve of the disc spring used for the conventional fastening mechanism. (A) is the load curve of the spring used with the fastening mechanism of this invention, (B) is the load curve of the spring of the comparative example. It is a graph showing the vibration transmissibility of the high frequency vibration of the spring of the fastening mechanism of this invention, and the disk spring of the conventional fastening mechanism. It is a graph of the vibration characteristic for demonstrating the setting of the natural frequency of a system. It is a graph showing the load characteristic of a disc spring. It is a schematic sectional side view showing the installation state of the fastening mechanism for the conventional vibration isolator. The load characteristics of a disc spring are represented, and (A) to (C) are graphs for explaining respective setting methods of load characteristics of an upper disc spring and a lower disc spring arranged in a conventional fastening mechanism for a vibration isolator. It is. It is a graph showing the load characteristic of the actual disk spring which a hysteresis produces, (A) is a case where the amplitude of a use range is a predetermined magnitude | size, (B) is a case where the amplitude of a use range is smaller than the case of (A) It is a graph of.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Lower spring (lower elastic member), 2 ... Upper spring (upper elastic member), 2A, 2B ... Contact part, 10, 20 ... Main part, 10A, 20A ... Hole part, 11, 21 ... First Cylindrical part (cylindrical part), 12, 22 ... Second cylindrical part (cylindrical part), 13, 23 ... First corner part (corner part), 14, 24 ... Second corner part (corner part), 100 ... Fastening mechanism 101 ... Bracket (first member) 102 ... Car body (second member) 103 ... Vibration source 104 ... Bolt (fixing jig) α, β ... Angle

Claims (6)

A fixing jig for fixing the first member and the second member, and an upper elastic member and a lower elastic member disposed on the upper side and the lower side of the first member,
One of the second member and one end of the fixing jig is disposed above the upper elastic member, and the second member and the fixing jig are disposed below the lower elastic member. The other end of the tool is arranged,
Fastening that holds the first member held by the upper elastic member and the lower elastic member by one end of the fixing jig and fixes the other end of the fixing jig to the second member In the mechanism,
The upper elastic member and the lower elastic member are made of metal,
At least the upper elasticity among the contact portion between the upper elastic member and the member disposed on the upper and lower sides thereof, and the contact portion between the lower elastic member and the member disposed on the upper and lower sides thereof. A fastening mechanism, wherein the contact portion of the member is fixed.   The fastening mechanism according to claim 1, wherein the upper elastic member is set to receive a tensile load in a vertical direction in an initial state.   The fastening mechanism according to claim 1, wherein load characteristics exhibited by the upper elastic member and the lower elastic member coincide with each other. The upper elastic member and the lower elastic member include a main body portion having a hole, a cylindrical portion provided on at least one of the inner peripheral portion and the outer peripheral portion of the main body portion, and the main body portion. A spring having a corner portion formed at a boundary portion with the cylindrical portion,
The main body portion of the spring extends in a direction intersecting the direction of the pressing force from the member located on the upper and lower sides of the spring,
The cylindrical portion of the spring protrudes from the peripheral portion of the main body portion toward one of the members located on the upper and lower sides of the spring,
The fastening mechanism according to claim 1, wherein the corner portion of the spring is elastically deformable so that the angle changes according to the pressing force. When the natural frequency of the system including the first member, the second member, and the fastening mechanism is f ₀ , and the vibration frequency of any of the first member and the second member is f ₁ , The fastening mechanism according to claim 1, wherein Formula 1 is satisfied.

  A vibration isolator comprising the fastening mechanism according to any one of claims 1 to 5.

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