Vibration isolation device

Abstract

To provide a vibration control device which can be downsized in an axial direction.SOLUTION: A dynamic damper 40 includes: a mass member 41; a third member 42; and an elastic member 43 connecting the mass member 41 with the third member 42. An outer peripheral surface of the third member 42 is connected to a film part 31 of a vibration control base 30 which covers an inner peripheral surface of a second member 20 (a small diameter part 22) and is disposed at the inner periphery side of the second member 2. The structure increases a dimension of the third member 42 in an axis L direction to utilize a space at the inner periphery side of the second member 20 effectively, compared with a structure in which an inner peripheral surface of the third member 42 is connected to an outer periphery surface of the second member 20 (the small diameter part 22). Accordingly, the vibration control device 1 can be downsized in the axis L direction for the space.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a vibration isolator, and more particularly to a vibration isolator that can be miniaturized in the axial direction.

Background Art

[0002] There is known a technique including a first mounting member 18 (first member), a cylindrical second mounting member 20 (second member), and a main body rubber elastic body 22 (vibration isolation base) that connects the first mounting member 18 and the second mounting member 20, and fixing a dynamic damper 16 to the second mounting member 20 (Patent Document 1).

[0003] The dynamic damper 16 includes a mass member 58, a cylindrical outer member 60 (third member), and a support rubber 62 (elastic member) that connects the mass member 58 and the cylindrical outer member 60.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the above-described conventional technique, since the inner peripheral surface of the upper end portion of the cylindrical outer member 60 (third member) is connected to the outer peripheral surface of the lower end portion of the second mounting member 20 (second member) to fix the dynamic damper 16 to the second mounting member 20, even if the flexible film 32 and the partition member 38 are omitted, the mass member 58 cannot be disposed on the inner peripheral side of the second mounting member 20. That is, the space formed by omitting the flexible film 32 and the partition member 38 cannot be utilized, and accordingly, there is a problem that the vibration isolator is enlarged in the axial direction.

[0006] The present invention has been made to solve the above-described problems, and an object thereof is to provide a vibration isolation device that can be miniaturized in the axial direction.

Means for Solving the Problems

[0007] To achieve this object, the vibration isolation device of the present invention includes a first member, a cylindrical second member, a vibration isolation base body that connects the first member and the second member and is made of a rubber-like elastic body, and a dynamic damper disposed on the second member. The dynamic damper includes a mass member that constitutes a mass body, a cylindrical third member, and an elastic member that connects the mass member and the third member and is made of a rubber-like elastic body. The outer peripheral surface of the third member of the dynamic damper is connected to the inner peripheral surface of the second member or the film portion of the vibration isolation base body that covers the inner peripheral surface of the second member, and is disposed on the inner peripheral side of the second member. , the elastic member includes a through-hole formed axially therethrough, and the mass member is formed as a solid material. is. The vibration isolator of the present invention includes a first member, a cylindrical second member, a vibration isolation base body that connects the first member and the second member and is composed of a rubber-like elastic body, and a dynamic damper disposed on the second member. The dynamic damper includes a mass member that constitutes a mass body, a cylindrical third member, and an elastic member that connects the mass member and the third member and is composed of a rubber-like elastic body. The outer peripheral surface of the third member of the dynamic damper is connected to the inner peripheral surface of the second member or the film portion of the vibration isolation base body that covers the inner peripheral surface of the second member, and is disposed on the inner peripheral side of the second member. The dynamic damper includes a first dynamic damper and a second dynamic damper, and the first dynamic damper and the second dynamic damper are arranged side by side in the axial direction. The vibration isolator of the present invention includes a first member, a cylindrical second member, a vibration isolation base body that connects the first member and the second member and is composed of a rubber-like elastic body, and a dynamic damper disposed on the second member. The dynamic damper includes a mass member that constitutes a mass body, a cylindrical third member, and an elastic member that connects the mass member and the third member and is composed of a rubber-like elastic body. The outer peripheral surface of the third member of the dynamic damper is connected to the inner peripheral surface of the second member or the film portion of the vibration isolation base body that covers the inner peripheral surface of the second member, and is disposed on the inner peripheral side of the second member. The third member includes a first protruding portion formed to protrude radially inward toward the region between the vibration isolation base body and the mass member. In the unloaded state, the first protruding portion and the mass member are separated from each other by a predetermined distance in the axial direction. The vibration isolator of the present invention includes a first member, a cylindrical second member, a vibration isolation base body that connects the first member and the second member and is made of a rubber-like elastic body, and a dynamic damper disposed on the second member. The dynamic damper includes a mass member that constitutes a mass body, a cylindrical third member, and an elastic member that connects the mass member and the third member and is made of a rubber-like elastic body. The outer peripheral surface of the third member of the dynamic damper is connected to the inner peripheral surface of the second member or the film portion of the vibration isolation base body that covers the inner peripheral surface of the second member, and is disposed on the inner peripheral side of the second member. The third member includes a second protruding portion formed to protrude radially inward toward a region on the opposite side of the vibration isolation base body with the mass member interposed therebetween. The second protruding portion is formed to protrude radially inward to a position facing the mass member in the axial direction. The vibration isolator of the present invention includes a first member, a cylindrical second member, a vibration isolation base body that connects the first member and the second member and is made of a rubber-like elastic body, and a dynamic damper disposed on the second member. The dynamic damper includes a mass member that constitutes a mass body, a cylindrical third member, and an elastic member that connects the mass member and the third member and is made of a rubber-like elastic body. The outer peripheral surface of the third member of the dynamic damper is connected to the inner peripheral surface of the second member or the film portion of the vibration isolation base body that covers the inner peripheral surface of the second member, and is disposed on the inner peripheral side of the second member. The second member is subjected to a throttling process at least at an end portion that is axially opposite to the vibration isolation base body.

Effects of the Invention

[0008] According to the vibration isolation device described in claim 1 , 2, 6, 9, 11 at the following effects are obtained. Since the outer peripheral surface of the third member of the dynamic damper is connected to the inner peripheral surface of the second member or the film portion of the vibration isolation base body that covers the inner peripheral surface of the second member and is disposed on the inner peripheral side of the second member, the space on the inner peripheral side of the second member can be effectively utilized. Therefore, the vibration isolation device can be miniaturized in the axial direction accordingly.

[0009] According to the vibration isolation device described in claim 1 the following effects are obtained. Since the elastic member includes a through-hole formed axially therethrough, the spring characteristics of the elastic member can be given a direction by adjusting the position and shape of the through-hole. , next

[0010] ​In addition, since the elastic member is provided with a throat portion, the space between the vibration isolation base and the dynamic damper can be communicated with the outside through the throat portion, so that an increase or decrease in the internal pressure of such a space due to the deformation of the vibration isolation base is suppressed, and the vibration isolation function of the vibration isolation base can be surely exhibited. As a result, it is not necessary to form a through hole in the mass member (the mass member can be formed as a solid material), so that the mass member can be miniaturized, and accordingly, the volume of the elastic member can be secured. As a result, the durability of the elastic member can be improved.

[0011] According to the vibration isolation device described in claim 2 the following effect is achieved. Since the first dynamic damper and the second dynamic damper are arranged side by side in the axial direction, the vibration damping function can be improved by using the first dynamic damper and the second dynamic damper. , next

[0012] According to the vibration isolation device described in claim 3 in addition to the effect achieved by the vibration isolation device described in claim 2 the following effect is achieved. In the no-load state, since the mass member of the first dynamic damper and the mass member of the second dynamic damper are separated from each other by a predetermined distance in the axial direction, contact between the mass member of the first dynamic damper and the mass member of the second dynamic damper is suppressed, and it is possible to suppress the vibration damping function of the first dynamic damper and the second dynamic damper from being inhibited.

[0013] According to the vibration isolation device described in claim 4 in addition to the effect achieved by the vibration isolation device described in claim 2 or 3 the following effect is achieved. Since the mass member of the first dynamic damper and the mass member of the second dynamic damper each include a through hole penetrating in the axial direction, the space between the vibration isolation base and the dynamic damper can be communicated with the outside through the through hole. Therefore, an increase or decrease in the internal pressure of such a space due to the deformation of the vibration isolation base is suppressed, and the vibration isolation function of the vibration isolation base can be surely exhibited.

[0014] In this case, since the cross-sectional area of the through-hole in the mass member of the second dynamic damper is formed larger than that of the through-hole in the mass member of the first dynamic damper, the mass members of the first dynamic damper and the second dynamic damper can be set to different masses. Therefore, even if the elastic members of the first dynamic damper and the second dynamic damper are set to the same shape, the natural frequencies of the first dynamic damper and the second dynamic damper can be made different. That is, the first dynamic damper and the second dynamic damper having different natural frequencies can be vulcanized and molded with a common mold, and accordingly, the product cost can be reduced.

[0015] According to the claim 5 of the vibration isolation device, in addition to the effects exhibited by the vibration isolation device described in claim 2 to 4 the following effect is exhibited. The elastic member of the first dynamic damper and the elastic member of the second dynamic damper each include a bored portion formed to penetrate in the axial direction, and the first dynamic damper and the second dynamic damper are arranged on the second member so that the bored portion in the elastic member of the first dynamic damper and the bored portion in the elastic member of the second dynamic damper are at different positions in the circumferential direction. Therefore, vibrations in different radial directions can be suppressed by the first dynamic damper and the second dynamic damper.

[0016] According to the claim 6 of the vibration isolation device, the following effect is exhibited. Since the third member includes a first protruding portion formed to protrude radially inward toward the region between the vibration isolation base and the mass member, when the vibration isolation base is deformed by a relatively large vibration input, contact between the deformed vibration isolation base and the mass member can be suppressed. Also, in the no-load state, since the first protruding portion and the mass member are separated from each other by a predetermined distance in the axial direction, contact between the first protruding portion and the mass member can be suppressed. As a result, contact between the mass member and other members (vibration isolation base, first protruding portion) can be suppressed, and it is possible to suppress the damping function of the dynamic damper from being inhibited.

[0017] In addition, since the first overhanging portion is formed, the vibration isolation base and the mass member can be arranged closer to each other in the axial direction. Therefore, the vibration isolation device can be downsized in the axial direction accordingly.

[0018] According to the claim 7 In addition to the effects exhibited by the vibration isolation device according to the claim 6 described, the following effects are exhibited. Since the first overhanging portion is formed to project radially inward to a position facing the mass member in the axial direction, when the vibration isolation base is deformed by a relatively large vibration input, it is possible to more reliably suppress contact between the deformed vibration isolation base and the mass member.

[0019] Since the elastic member includes a connecting portion that connects the mass member and the first overhanging portion in the axial direction, the connecting area of the elastic member with the mass member and the third member, as well as the volume of the elastic member, can be ensured accordingly, improving durability. Also, by adjusting the volume of the connecting portion, it is possible to easily adjust the natural frequency of the dynamic damper. Furthermore, since contact between the mass member and the first overhanging portion can be restricted by the connecting portion, the mass member and the first overhanging portion can be arranged closer to each other in the axial direction accordingly. Therefore, the vibration isolation device can be downsized in the axial direction accordingly.

[0020] According to the claim 8 In addition to the effects exhibited by the vibration isolation device according to the claim 6 or 7 described, the following effects are exhibited. Since it is provided with a stopper rubber that covers the surface of the first overhanging portion on the side facing the vibration isolation base and is composed of a rubber-like elastic body, generation of abnormal noise when the vibration isolation base deformed by a relatively large deformation input contacts the first overhanging portion can be suppressed by the stopper rubber.

[0021] According to the claim 9 In accordance with the vibration isolation device described in , next It has the following effects. The third member includes a second protruding portion that protrudes radially inward toward a region on the opposite side of the vibration isolation base with the mass member interposed therebetween. Since the second protruding portion protrudes radially inward to a position facing the mass member in the axial direction, the second protruding portion can restrict the mass member from falling off when the elastic member breaks. Further, by covering the outer surface of the elastic member with the second protruding portion, such an elastic member can be protected.

[0022] According to claim 10 the vibration isolation device described above, in addition to the effects of the vibration isolation device described in claim 9 it has the following effects. Since the elastic member includes a connecting portion that axially connects the mass member and the second protruding portion, the connecting area between the elastic member, the mass member, and the third member, as well as the volume of the elastic member, can be ensured accordingly, improving durability. Further, by adjusting the volume of the connecting portion, it is possible to easily adjust the natural frequency of the dynamic damper. Furthermore, since the contact between the mass member and the second protruding portion can be restricted by the connecting portion, the mass member and the second protruding portion can be arranged closer to each other in the axial direction accordingly. Therefore, the vibration isolation device can be downsized in the axial direction accordingly.

[0023] According to claim 11 the vibration isolation device described above , next it has the following effects. Since the second member is subjected to a necking process at least at an end portion that is axially opposite to the vibration isolation base, the axial movement of the dynamic damper can be restricted by the above-mentioned end portion of the second member, suppressing the dynamic damper from coming out from the inner peripheral side of the second member.

[0024] Further, in addition to the end portion that is axially opposite to the vibration isolation base, when the second member is subjected to a necking process also in at least a region where the dynamic damper is disposed on the inner peripheral side, the dynamic damper can be more firmly held on the inner peripheral side of the second member, and radial pre-compression can be applied to the elastic member of the dynamic damper, improving the durability of such an elastic member.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0026] Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. First, referring to Fig. 1, the vibration isolator 1 in the first embodiment will be described. Fig. 1 is a longitudinal sectional view of the vibration isolator 1 in the first embodiment of the present invention. In this embodiment, an engine mount will be described as an example of the application target of the vibration isolator 1.

[0027] The vibration isolator 1 includes a first member 10 attached to the engine side, a substantially cylindrical second member 20 attached to the vehicle body side, a vibration isolation base 30 connecting these first member 10 and second member 20, and a dynamic damper 40 disposed on the inner peripheral side of the second member 20.

[0028] The first member 10 is formed in a substantially cylindrical shape from an aluminum alloy, and a female screw is recessed along the axis L at the center of its upper end surface. The second member 20 is formed from a steel material in a substantially cylindrical shape centered on the axis L, and includes a large-diameter portion 21, a small-diameter portion 22 having a smaller diameter than the large-diameter portion 21, and a connecting portion 23 connecting these large-diameter portion 21 and small-diameter portion 22.

[0029] The vibration isolation base 30 is formed in a substantially frustum shape (trapezoidal in cross section) from a rubber-like elastic body, and is vulcanized and adhered to the outer surface of the first member 10 (the outer peripheral surface of the cylindrical portion and the lower surface of the flange portion) and the inner peripheral surface of the second member 20 (the large-diameter portion 21 and the connecting portion 23). A film portion 31 is continuous with the lower end portion of the vibration isolation base 30, and the inner peripheral surface of the second member 20 (the small-diameter portion 22) is covered by the film portion 31.

[0030] The dynamic damper 40 includes a mass member 41 that constitutes a mass body, a third member 42 formed from a steel material in a substantially cylindrical shape centered on the axis L, and an elastic member 43 that connects these mass member 41 and the third member 42.

[0031] The mass member 41 is formed in a substantially disk shape centered on the axis L from cast iron, and a through hole 41a is formed through the center along the axis L. The elastic member 43 is formed in an annular shape in a front view (viewed in the direction of the axis L), and is vulcanized and adhered to the outer peripheral surface of the mass member 41 and the inner peripheral surface of the third member 42.

[0032] The dynamic damper 40 is disposed on the inner peripheral side of the second member 20 (the small-diameter portion 22) by connecting the outer peripheral surface of the third member 42 to the film portion 31 in a close contact state. Therefore, the space on the inner peripheral side of the second member 20 (the small-diameter portion 22) can be effectively utilized as the installation space for the dynamic damper 40, and accordingly, the vibration isolation device 1 can be downsized in the direction of the axis L.

[0033] A through hole 41a is formed through the mass member 41. Thereby, the space S between the vibration isolation base 30 and the dynamic damper 40 can be communicated with the outside through the through hole 41a. As a result, an increase or decrease in the internal pressure of the space S due to the deformation of the vibration isolation base 30 is suppressed, and the vibration isolation function of the vibration isolation base 30 can be surely exhibited.

[0034] Next, a method for manufacturing the vibration isolation device 1 will be described. In the manufacture of the vibration isolation device 1, first, a molded body in which the first member 10 and the second member 20 are connected by the vibration isolation base 30 is vulcanization-molded by a first vulcanization mold, and the dynamic damper 40 is vulcanization-molded by a second vulcanization mold.

[0035] Next, the dynamic damper 40 is inserted into the inner peripheral side of the second member 20 (small-diameter portion 22) from the opening on the lower end side of the molded body, and the dynamic damper 40 is attached. Then, the second member 20 with the dynamic damper 40 attached is subjected to a squeezing (diameter reduction) process in the radially inner direction. Thus, the manufacturing of the vibration isolator 1 is completed.

[0036] In the present embodiment, the entire second member 20 (large-diameter portion 21, connecting portion 23, and small-diameter portion 22) is subjected to a squeezing process. As a result, the outer peripheral surface of the third member 42 is brought into close contact with the film portion 31, and the dynamic damper 40 can be firmly held on the inner peripheral side of the second member 20 (small-diameter portion 22). In addition, pre-compression in the radial direction can be applied to the vibration isolation base 30 and the elastic member 43 to improve their durability.

[0037] Also, the lower end of the second member 20 (the lower end portion on the lower side of FIG. 1, which is opposite to the vibration isolation base 30 in the axial direction of the axis L) is folded back inward in the radial direction by the above-described squeezing process. Therefore, the movement of the dynamic damper 40 in the axial direction of the axis L can be restricted by the lower end of the second member 20, and the dynamic damper 40 can be prevented from coming out of the inner peripheral side of the second member 20 (small-diameter portion 22).

[0038] Note that the range in which the second member 20 is subjected to a squeezing (diameter reduction) process in the radially inner direction may be only the lower end of the second member 20, or may be only the small-diameter portion 22 (including the lower end of the second member 20).

[0039] Next, referring to FIG. 2, the vibration isolator 201 in the second embodiment will be described. In the first embodiment, the case where the space S is communicated to the outside through the through hole 41a was described, but the space S in the second embodiment is communicated to the outside through the draining portion 243a.

[0040] FIG. 2(a) is a longitudinal sectional view of the vibration isolator 201 in the second embodiment, and FIG. 2(b) is a cross-sectional view of the vibration isolator 201 taken along line IIb-IIb in FIG. 1(a). Note that the same reference numerals are given to the same parts as those in the first embodiment, and the description thereof is omitted.

[0041] As shown in FIG. 2, in the second embodiment, no through hole is formed in the mass member 241, and the mass member 241 is formed as a substantially disk-shaped solid material centered on the axis L. On the other hand, a through portion 243a is formed in the elastic member 243. The through portion 243a is a space formed by penetrating the elastic member 243 in the direction of the axis L, and is formed at two locations with a 180-degree phase difference. By forming the through portion 243a, it is possible to give a directionality to the spring characteristics of the elastic member 243.

[0042] According to the vibration isolator 201, since the through portion 243a penetrates and is formed in the elastic member 243, the space S between the vibration isolation base 30 and the dynamic damper 240 can be communicated with the outside through the through portion 243a. Thereby, it is possible to suppress an increase or decrease in the internal pressure of the space S due to the deformation of the vibration isolation base 30, and the vibration isolation function of the vibration isolation base 30 can be surely exhibited.

[0043] Further, since no through hole is formed in the mass member 241, the mass of the mass member 241 can be ensured, and accordingly, the outer shape (for example, the outer diameter) of the mass member 241 can be reduced. Therefore, in the limited space on the inner peripheral side of the second member 20 (small diameter portion 22), the volume of the elastic member 243 (for example, the length dimension of the elastic member 243 in the left-right direction in FIG. 2(a)) can be ensured. As a result, the durability of the elastic member 243 can be improved.

[0044] Next, referring to FIG. 3, the vibration isolator 301 in the third embodiment will be described. In the first embodiment, the case where no other member is disposed between the vibration isolation base 30 and the mass member 41 has been described. However, a protruding portion 344 is disposed between the vibration isolation base 30 and the mass member 41 in the third embodiment.

[0045] FIG. 3 is a longitudinal sectional view of the vibration isolator 301 in the third embodiment. The same parts as those in the above embodiments are denoted by the same reference numerals, and the description thereof will be omitted.

[0046] As shown in FIG. 3, the dynamic damper 340 in the third embodiment includes a third member 342 made of a steel material and having a substantially cylindrical shape centered on the axis L. The outer peripheral surface of the third member 342 is connected to the film portion 31 in a close contact state, so that the third member 342 is disposed on the inner peripheral side of the second member 20 (small-diameter portion 22).

[0047] The third member 342 includes an overhanging portion 344 formed to project radially inward from an end portion on the upper side in the axial direction L (the side of the vibration isolation base 30) toward a region (space S) between the vibration isolation base 30 and the mass member 41. Thereby, even when the vibration isolation base 30 is compressed by a relatively large vibration input (for example, crossing a protrusion) and greatly deformed toward the dynamic damper 340 side, the deformed vibration isolation base 30 can be received by the overhanging portion 344, and contact between the vibration isolation base 30 and the mass member 41 can be suppressed. As a result, it is possible to suppress the damping function of the dynamic damper 340 from being inhibited.

[0048] The overhanging portion 344 and the mass member 41 are separated from each other by a predetermined distance in the axial direction L in a no-load state (a stationary state in which no vibration is input). Specifically, the separation distance between the overhanging portion 344 and the mass member 41 is set to a dimension larger than the maximum amplitude of the mass member 41 (the amplitude when resonating at the natural frequency in the axial direction L). Thereby, contact between the overhanging portion 344 and the mass member 41 can be suppressed. As a result, it is possible to suppress the damping function of the dynamic damper 340 from being inhibited.

[0049] In addition, since the deformation of the vibration isolation base 30 (displacement in the direction approaching the mass member 41) can be restricted by the overhanging portion 344, the vibration isolation base 30 and the mass member 41 can be arranged closer to each other in the axial direction L. Therefore, the vibration isolation device 301 can be downsized in the axial direction accordingly.

[0050] Note that a film portion (stopper rubber) made of a rubber-like elastic body may be disposed on the outer surface of the protruding portion 344 (at least the upper or lower surface in FIG. 3). This is because it is possible to suppress the generation of knocking sounds (abnormal sounds) when the anti-vibration base 30 or the mass member 41 comes into contact with the protruding portion 344. The film portion (stopper rubber) may be continuous with the elastic member 43 or may be separate from the elastic member 43. Concavities, convexities, or grooves may be formed on the outer surface of the film portion (stopper rubber).

[0051] A circular opening 344a centered on the axis L is formed in the protruding portion 344. Therefore, the space S between the anti-vibration base 30 and the dynamic damper 340 can be communicated with the outside through the opening 344a of the protruding portion 344 and the through-hole 41a of the mass member 41. Thereby, it is possible to suppress the increase and decrease of the internal pressure of the space S due to the deformation of the anti-vibration base 30, and the anti-vibration function of the anti-vibration base 30 can be surely exhibited.

[0052] Next, with reference to FIG. 4, the anti-vibration device 401 in the fourth embodiment will be described. In the third embodiment, the case where the protruding portion 344 is disposed between the anti-vibration base 30 and the mass member 41 is described. However, the protruding portion 444 in the fourth embodiment is disposed on the side opposite to the anti-vibration base 30 with the mass member 41 interposed therebetween.

[0053] FIG. 4 is a longitudinal sectional view of the anti-vibration device 401 in the fourth embodiment. Note that the same reference numerals are given to the same parts as in the above embodiments, and the description thereof is omitted.

[0054] As shown in FIG. 4, the dynamic damper 440 in the fourth embodiment includes a third member 442 made of a steel material in a substantially cylindrical shape centered on the axis L, and the outer peripheral surface of the third member 442 is connected in close contact with the film portion 31, so that it is disposed on the inner peripheral side of the second member 20 (small-diameter portion 22).

[0055] The third member 442 includes an overhanging portion 444 formed to project radially inward from an end portion on the lower side in the axial direction L (the side opposite to the vibration isolation base 30) toward a region on the side opposite to the vibration isolation base 30 with the mass member 41 interposed therebetween. The overhanging portion 444 is formed to project radially inward to a position facing the mass member 41 in the axial direction L (a position overlapping the mass member 41 when viewed in the axial direction L).

[0056] That is, a circular opening 444a centered on the axis L is formed in the overhanging portion 444, and the inner diameter of the opening 444a is set to a dimension smaller than the outer diameter of the mass member 41. Therefore, the mass member 41 cannot pass through the opening 444a. Thereby, when the elastic member 443 breaks, the overhanging portion 444 can restrict the mass member 41 from falling off.

[0057] In this case, since the overhanging portion 444 is formed to project radially inward to a position facing the mass member 41 in the axial direction L, the overhanging portion 444 can cover the outer surface exposed outside the elastic member 443. Therefore, it is possible to suppress foreign objects (for example, flying stones during running) from colliding with the elastic member 443 and protect the elastic member 443.

[0058] The elastic member 443 is connected not only to the third member 442 (the cylindrical portion centered on the axis L) but also to the overhanging portion 444. Thereby, it is possible to secure the connection area (the vulcanization adhesion area) between the elastic member 443, the third member 442, and the overhanging portion 444, and to secure the volume of the elastic member 443 (for example, the thickness dimension of the elastic member 443 in the vertical direction in FIG. 4). As a result, the durability of the elastic member 443 can be improved.

[0059] Further, the elastic member 443 includes a connecting portion 443b that connects the mass member 41 and the overhanging portion 444 in the axial direction L. That is, the connecting portion 443b is connected to the portions facing each other between the mass member 41 and the overhanging portion 444 in the axial direction L.

[0060] As a result, in addition to the above-described improvement in durability, by adjusting the volume of the connecting portion 443b (for example, the length dimension of the connecting portion 443b in the left-right direction in FIG. 4), it is possible to easily adjust (design, change) the natural frequency of the dynamic damper 440. Further, the contact between the mass member 41 and the overhanging portion 444 can be restricted by the connecting portion 443b. Therefore, it is possible to suppress the generation of knocking sound (abnormal sound) due to the contact between the mass member 41 and the overhanging portion 444. Further, since it is not necessary to consider the contact between the two, the mass member 41 and the overhanging portion 444 can be arranged closer to each other in the axial direction of the axis L, and accordingly, the vibration isolator 401 can be downsized in the axial direction of the axis L.

[0061] In addition, according to the vibration isolator 401, since it includes the through hole 41a and the opening 444a, similar to the above-described embodiments, it is possible to suppress an increase or decrease in the internal pressure of the space S due to the deformation of the vibration isolation base 30, and reliably exhibit the vibration isolation function by the vibration isolation base 30.

[0062] Next, with reference to FIG. 5, the vibration isolator 501 in the fifth embodiment will be described. In the first embodiment, the case where the vibration isolator 1 includes one dynamic damper 40 has been described. However, the vibration isolator 501 in the fifth embodiment includes two dynamic dampers 540.

[0063] FIG. 5(a) is a longitudinal sectional view of the vibration isolator 501 in the fifth embodiment, FIG. 5(b) is a cross-sectional view of the vibration isolator 501 taken along line Vb-Vb in FIG. 5(a), and FIG. 5(c) is a cross-sectional view of the vibration isolator 501 taken along line Vc-Vc in FIG. 5(a). Note that the same reference numerals are given to the same parts as in the above-described embodiments, and the description thereof is omitted.

[0064] As shown in FIG. 5, in the vibration isolator 501 in the fifth embodiment, two dynamic dampers 540 are arranged side by side in the axial direction of the axis L on the inner peripheral side of the second member 20 (small-diameter portion 22). The dynamic damper 540 is substantially the same in configuration as the dynamic dampers 40 and 240, except that the dimension (thickness dimension) in the axial direction of the axis L is reduced. Therefore, a detailed description of each configuration is omitted.

[0065] The upper and lower dynamic dampers 540, 540 are disposed on the inner circumferential side of the second member 20 (small-diameter portion 22) with different phases so that the circumferential positions of the mutual best portions 543a are different from each other.

[0066] In the present embodiment, the upper and lower dynamic dampers 540, 540 are disposed with a 90-degree phase difference. Therefore, the upper and lower dynamic dampers 540, 540 have different spring characteristics in the direction orthogonal to the axis L (radial direction). That is, vibrations in different radial directions can be suppressed by the upper and lower dynamic dampers 540, 540, respectively.

[0067] On the other hand, the upper and lower dynamic dampers 540, 540 have the same spring characteristics in the direction of the axis L. Therefore, in the direction of the axis L, the upper and lower dynamic dampers 540, 540 function as one dynamic damper, so that the mass of the mass body is increased accordingly (two mass members 541 can function as the mass body in the direction of the axis L), and the vibration damping effect can be improved.

[0068] Also, in the direction of the axis L, the two mass members 541 of the upper and lower dynamic dampers 540, 540 can be displaced in the same phase, so that these mass members 541 can be arranged closer to each other in the direction of the axis L. Therefore, the vibration isolation device 501 can be downsized in the axial direction accordingly.

[0069] According to the vibration isolation device 501, since the dynamic dampers 540 having the same configuration are arranged with different phases, while ensuring the above effects, the upper and lower dynamic dampers 540, 540 can be vulcanized and molded with a common mold. Therefore, the product cost can be reduced accordingly.

[0070] Next, with reference to FIG. 6, the vibration isolation device 601 in the sixth embodiment will be described. In the fifth embodiment, the case where the vibration isolation device 501 includes the dynamic dampers 540, 540 having the same configuration has been described. However, the vibration isolation device 601 in the sixth embodiment includes dynamic dampers 540, 640 having different configurations.

[0071] FIG. 6 is a longitudinal sectional view of the vibration isolator 601 in the sixth embodiment. The same parts as those in the above embodiments are denoted by the same reference numerals, and the description thereof is omitted.

[0072] As shown in FIG. 6, in the vibration isolator 601 in the sixth embodiment, a dynamic damper 540 and a dynamic damper 640 are arranged side by side in the axial direction of the shaft L on the inner peripheral side of the second member 20 (small-diameter portion 22). The dynamic damper 560 has substantially the same configuration as that of the dynamic damper 540, except that the through-hole 641a has a smaller diameter than the through-hole 541a. Therefore, detailed description of each configuration is omitted.

[0073] The mass members 541 and 641 are set to have different masses due to the different inner diameters (cross-sectional areas) of the through-holes 541a and 641a. As a result, the dynamic damper 640 has a natural frequency different from that of the dynamic damper 540 in both the axial direction of the shaft L and the direction orthogonal to the shaft L (radial direction). Therefore, vibrations with different frequencies can be suppressed by the dynamic dampers 540 and 640, respectively.

[0074] As described above, in this embodiment, since the inner diameters of the through-holes 541a and 641a are made different to make the mass members 541 and 641 have different masses, the mass members 541 and 641 can have the same outer diameter. That is, the elastic member 543 of the dynamic damper 540 and the elastic member 543 of the dynamic damper 640 can have the same shape. Also, the mass members 541 and 641 can have the same thickness dimension. Therefore, the dynamic dampers 540 and 640 can be vulcanized and molded using a common mold, and the product cost can be reduced accordingly.

[0075] The separation distance in the axial direction between the mass member 541 and the mass member 641 is set to a dimension larger than the maximum amplitude of the mass members 541 and 641 (the amplitude when resonating at the natural frequency in the axial direction). Thereby, contact between the mass members 541 and 641 can be suppressed. As a result, it is possible to suppress the inhibition of the vibration damping function of the dynamic dampers 540 and 640.

[0076] Although the present invention has been described based on the embodiments, it is easily conceivable that the present invention is not limited to the above embodiments at all, and various improvements and modifications can be made without departing from the gist of the present invention.

[0077] In each of the above embodiments, an engine mount has been exemplified as an application target of the vibration isolators 1 to 601, but the application target is arbitrary. Other application targets include, for example, motor mounts, member mounts, and differential mounts.

[0078] The numerical values shown in each of the above embodiments are examples, and any numerical values can be adopted. For example, although the case where the number of formed portions 243a and 543a of the excellent portion is 2 has been described, it may be 1 or 3 or more. Although the case where the number of formed through holes 41a, 541a, and 641a is 1 has been described, it may be 2 or more. Although the case where the number of arranged dynamic dampers 40 to 640 is 1 or 2 has been described, it may be 3 or more. In the fifth and sixth embodiments, although the case where the phases are different by 90 degrees has been described, it may be less than 90 degrees or more than 90 degrees.

[0079] A part of each of the above embodiments may be replaced with a part of another embodiment, or a part of each of the above embodiments may be added to another embodiment. For example, overhanging portions 344 and 444 may be added to the third member 542 of the dynamic dampers 540 and 640.

[0080] A part of each of the above embodiments may be omitted. For example, the film portion 31 that covers the inner peripheral surface of the small-diameter portion 22 of the second member 20 may be omitted. That is, a configuration in which the outer peripheral surfaces of the third members 42 to 542 are directly connected to the inner peripheral surface of the second member 20 (small-diameter portion 22) may also be used. One or both of the through holes 41a, 541a or the excellent portions 243a, 543a may be omitted. The connecting portion 443b may be omitted.

[0081] In each of the above embodiments, the case where the vibration isolation base 30 is formed in a substantially frustum shape (trapezoidal in cross section) centered on the axis L has been described, but other shapes may also be used. For example, the vibration isolation base 30 may have a shape in which the first member 10 is offset from the axis L by a predetermined distance in a direction perpendicular to the axis L, or may have a shape in which a through-hole is formed in the direction of the axis L.

[0082] In the above-described third embodiment, the dynamic damper 340 may be arranged in an upside-down posture. In this case, it is possible to suppress the mass member 41 from falling off when the elastic member 43 breaks. Further, it is possible to suppress foreign matter (for example, a flying stone during traveling) from colliding with the elastic member 43. Similarly, in the above-described fourth embodiment, the dynamic damper 440 may be arranged in an upside-down posture. In this case, in addition to the effects described in the above-described fourth embodiment, the overhanging portion 444 suppresses contact between the vibration isolation base 30 and the mass member 41, and it is possible to suppress the damping function of the dynamic damper 440 from being inhibited. Further, since the vibration isolation base 30 and the mass member 41 can be arranged closer to each other in the axial direction of the axis L, the vibration isolation device 401 can be miniaturized in the axial direction.

[0083] In the above-described fifth embodiment, the case where the elastic member 543 of one dynamic damper 540 and the elastic member 543 of the other dynamic damper 540 are configured identically, and in the above-described sixth embodiment, the case where the elastic member 543 of the dynamic damper 540 and the elastic member 543 of the dynamic damper 640 are configured identically have been described, respectively. However, the material and / or rubber hardness of the rubber-like elastic body may be made different. While enabling vulcanization molding with a common mold, the natural frequencies can be made to differ more greatly.

[0084] In the above-described sixth embodiment, as a means for varying the masses of the mass members 541 and 641, a method of adjusting (changing) the inner diameters (cross-sectional areas) of the through holes 541a and 641a was described, but other means may be employed. Examples of other means include, for example, a method of forming the mass members 541 and 641 from materials having different specific gravities (for example, one made of a metal material and the other made of a resin material), and a method of varying the number of formed through holes 541a and 641a. In this case, it is preferable that the mass members 541 and 641 have the same shape (outer diameter, thickness dimensions). This is because the dynamic dampers 540 and 640 can be vulcanization molded using a common mold, thereby reducing the product cost accordingly.

Explanation of Signs

[0085] 1,201,301,401,501,601 Vibration Isolation Device 10 First Member 20 Second Member 30 Vibration Isolation Base 31 Film Portion 40,240,340,440 Dynamic Damper 540,640 Dynamic Damper (First Dynamic Damper, Second Dynamic Damper) 41,241,541,641 Mass Member 41a,541a,641a Through Hole 42,342,442,542 Third Member 43,243,443,543 Elastic Member 243a,543a Scooped Portion 443b Connecting Portion 344 Overhanging Portion (First Overhanging Portion) 444 Overhanging Portion (Second Overhanging Portion) L Axis

Claims

1. A vibration isolator comprising a first member, a cylindrical second member, a vibration isolation base body that connects the first member and the second member and is made of a rubber-like elastic body, and a dynamic damper disposed on the second member, The dynamic damper includes a mass member that constitutes a mass body, a cylindrical third member, and an elastic member that connects the mass member and the third member and is made of a rubber-like elastic body, The dynamic damper is disposed on the inner circumferential side of the second member, wherein an outer circumferential surface of the third member is connected to an inner circumferential surface of the second member or a film portion of the vibration isolation base body that covers the inner circumferential surface of the second member, The elastic member includes a through-hole formed to penetrate in the axial direction, The vibration isolator is characterized in that the mass member is formed as a solid material.

2. A vibration isolator comprising a first member, a cylindrical second member, a vibration isolation base body that connects the first member and the second member and is made of a rubber-like elastic body, and a dynamic damper disposed on the second member, The dynamic damper includes a mass member that constitutes a mass body, a cylindrical third member, and an elastic member that connects the mass member and the third member and is made of a rubber-like elastic body, The dynamic damper is disposed on the inner circumferential side of the second member, wherein an outer circumferential surface of the third member is connected to an inner circumferential surface of the second member or a film portion of the vibration isolation base body that covers the inner circumferential surface of the second member, The dynamic damper includes a first dynamic damper and a second dynamic damper, The vibration isolator is characterized in that the first dynamic damper and the second dynamic damper are arranged side by side in the axial direction.

3. The vibration isolator according to claim 2, characterized in that in a no-load state, a mass member of the first dynamic damper and a mass member of the second dynamic damper are separated from each other by a predetermined distance in the axial direction.

4. The mass member of the first dynamic damper and the mass member of the second dynamic damper each have a through hole penetrating in the axial direction. The elastic member of the first dynamic damper and the elastic member of the second dynamic damper are set to have the same shape. The vibration isolation device according to claim 2 or 3, wherein the cross-sectional area of the through hole in the mass member of the second dynamic damper is formed larger than the cross-sectional area of the through hole in the mass member of the first dynamic damper.

5. The elastic member of the first dynamic damper and the elastic member of the second dynamic damper each have a reamed portion formed by penetrating in the axial direction. The first dynamic damper and the second dynamic damper are disposed on the second member such that the reamed portion in the elastic member of the first dynamic damper and the reamed portion in the elastic member of the second dynamic damper are at different positions in the circumferential direction. The vibration isolation device according to any one of claims 2 to 4.

6. A first member, a cylindrical second member, a vibration isolation base body that connects the first member and the second member and is composed of a rubber-like elastic body, and a dynamic damper disposed on the second member. The dynamic damper includes a mass member constituting a mass body, a cylindrical third member, and an elastic member that connects the mass member and the third member and is composed of a rubber-like elastic body. The outer peripheral surface of the third member of the dynamic damper is connected to the inner peripheral surface of the second member or the film portion of the vibration isolation base body covering the inner peripheral surface of the second member, and is disposed on the inner peripheral side of the second member. The third member includes a first overhanging portion formed to overhang radially inward toward the region between the vibration isolation base body and the mass member. The vibration isolation device, wherein in the unloaded state, the first overhanging portion and the mass member are separated from each other by a predetermined distance in the axial direction.

7. The first protruding portion is formed to protrude radially inward to a position facing the mass member in the axial direction. The vibration isolator according to claim 6, wherein the elastic member includes a connecting portion that axially connects the mass member and the first protruding portion.

8. The vibration isolator according to claim 6 or 7, further comprising a stopper rubber made of a rubber-like elastic body that covers a surface of the first protruding portion facing the vibration isolation base.

9. A vibration isolator comprising a first member, a cylindrical second member, a vibration isolation base made of a rubber-like elastic body that connects the first member and the second member, and a dynamic damper disposed on the second member. The dynamic damper includes a mass member that constitutes a mass body, a cylindrical third member, and an elastic member made of a rubber-like elastic body that connects the mass member and the third member. The dynamic damper is disposed on the inner peripheral side of the second member, wherein an outer peripheral surface of the third member is connected to an inner peripheral surface of the second member or a film portion of the vibration isolation base that covers the inner peripheral surface of the second member. The third member includes a second protruding portion that is formed to protrude radially inward toward a region on the opposite side of the vibration isolation base with the mass member interposed therebetween. The vibration isolator is characterized in that the second protruding portion is formed to protrude radially inward to a position facing the mass member in the axial direction.

10. The vibration isolator according to claim 9, wherein the elastic member includes a connecting portion that axially connects the mass member and the second protruding portion.

11. A vibration isolator comprising a first member, a cylindrical second member, a vibration isolation base made of a rubber-like elastic body that connects the first member and the second member, and a dynamic damper disposed on the second member. The dynamic damper includes a mass member that constitutes a mass body, a cylindrical third member, and an elastic member made of a rubber-like elastic body that connects the mass member and the third member. The dynamic damper is connected such that the outer peripheral surface of the third member is connected to the inner peripheral surface of the second member or the film portion of the vibration isolation base covering the inner peripheral surface of the second member, and is disposed on the inner peripheral side of the second member. The vibration isolation device is characterized in that the second member is subjected to a throttling process at least at an end portion axially opposite to the vibration isolation base.

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