Vibration isolation components
The vibration-damping member adjusts its rigidity based on displacement to address the mismatched absorption characteristics of existing members, effectively absorbing vibrations of varying amplitudes, enhancing riding comfort.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- FUKOKU CO LTD
- Filing Date
- 2024-11-12
- Publication Date
- 2026-05-22
Smart Images
Figure 2026085071000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a vibration isolation member, and more particularly, to a vibration isolation member that is interposed between an operating device and its support member to absorb vibrations of the operating device.
Background Art
[0002] Patent Document 1 discloses a shock absorber in which a portion that deforms during shock absorption is made of a fiber-reinforced resin and the deforming portion is a cylindrical body. When this shock absorber is subjected to a shock, the cylindrical body breaks into a plurality of parts along the axial direction and is configured to be deformed outward of the cylindrical body. This shock absorber is disposed between the skeletal structure of a vehicle and a bumper reinforcement for the purpose of shock absorption during a collision of the vehicle body.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] By the way, there is known an operating device that generates vibrations with a relatively large amplitude at startup, while the amplitude of the vibrations becomes smaller during steady operation than at startup. A vibration isolation member for absorbing vibrations of the operating device is disposed between such an operating device and its support member. Such a vibration isolation member is, for example, a mount bush that is a cylindrical elastic body formed from a rubber material, and it is preferable that the vibration absorption characteristics be adjusted according to the vibration characteristics of the operating device.
[0005] However, if the vibration absorption characteristics of the vibration isolation member are matched to those at the start of the operating device, the rigidity of the vibration isolation member becomes excessive, and as a result, there is a risk that it will not be able to adequately absorb small amplitude vibrations during steady-state operation of the operating device. On the other hand, if the rigidity of the vibration isolation member is reduced to the point where it breaks when subjected to impact, as in the shock absorber described in Patent Document 1, it will not be able to adequately absorb large amplitude vibrations at the start of the operating device. Therefore, there is a need for a vibration isolation member that can change its vibration absorption characteristics according to the amplitude of vibration from the operating device, or in other words, according to the amount of displacement of the displaced part that displaces in response to vibration from the operating device.
[0006] The present invention has been made in view of these problems, and aims to provide a vibration-damping member that can change its vibration absorption characteristics according to the amount of displacement of a displacement part that is displaced in response to vibrations from an operating device. [Means for solving the problem]
[0007] To achieve the above objective, the vibration-damping member of the present invention is interposed between an operating device and its support member to absorb vibrations of the operating device, and comprises a displacement portion formed in the radial center of the vibration-damping member that displaces in response to vibrations from the operating device, a vibration-absorbing portion extending radially outward from the displacement portion and absorbing vibrations, and a regulating portion formed radially outward from the vibration-absorbing portion and restricting the radial displacement of the vibration-absorbing portion, wherein the vibration-absorbing portion forms a plurality of elastic portions that change in rigidity according to the amount of displacement of the displacement portion. [Effects of the Invention]
[0008] According to the vibration-damping member of the present invention, the vibration absorption characteristics can be changed according to the amount of displacement of the displacement part that is displaced in response to vibrations from the operating device. [Brief explanation of the drawing]
[0009] [Figure 1] This is a side view of a motor unit using a vibration-damping member according to one embodiment of the present invention. [Figure 2] This is a disassembled perspective view of the mounting section. [Figure 3] This is a plan view of the mounting section. [Figure 4] This graph shows the reaction force of the vibration-damping member in response to the displacement of the displaced part. [Figure 5] This is a plan view of the mounting section of the motor unit during startup. [Modes for carrying out the invention]
[0010] Hereinafter, a vibration-damping member 1 according to one embodiment of the present invention will be described with reference to the drawings. Figure 1 shows a side view of a motor unit 2 using the vibration-damping member 1. The vibration-damping member 1 is a cylindrical elastic body integrally molded from, for example, a rubber material, and is a so-called mount bush. The vibration-damping member 1 is interposed, for example, between a motor unit (operating device) 2 that drives an electric vehicle and a vehicle frame (supporting member) 3 that supports the motor unit 2, and absorbs vibrations transmitted from the motor unit 2 to the vehicle frame 3.
[0011] The motor unit 2 is formed by connecting a motor 4, a reduction gear 6, and an inverter 8, and a mount frame 10 is attached to the outer surface 2a of the motor unit 2. A cylindrical mount portion 12 is integrally formed on the outer surface 2a of the motor unit 2 and the outer surface 10a of the mount frame 10. The vibration damping member 1 is fitted into the inner circumferential surface 12a of the mount portion 12, and the outer circumferential surface 1a of the vibration damping member 1 is fixed to the inner circumferential surface 12a by adhesive or the like.
[0012] Figure 2 shows an exploded perspective view of the mounting section 12. Stud bolts (support bolts) 14 are erected from the vehicle frame 3, and the stud bolts 14 are inserted through a sleeve 15 into the radial center (hereinafter simply referred to as "radial direction") of the vibration-damping member 1. More specifically, the vibration-damping member 1 consists of a displacement section 16, a vibration absorption section 18, and a regulating section 20. The displacement section 16 is an inner circumferential wall section 22 formed in the radial center of the vibration-damping member 1 that displaces in response to vibrations from the motor unit 2, and a sleeve 15 is fitted inside the displacement section 16. Nuts 23 are screwed onto the stud bolts 14 inserted into the sleeve 15, thereby connecting the motor unit 2 and the vehicle frame 3 via the vibration-damping member 1 at the mounting section 12.
[0013] The vibration absorbing section 18 extends radially outward from the displacement section 16 and absorbs vibrations of the motor unit 2 transmitted via the mount section 12. The restricting section 20, in other words, is an outer peripheral wall section 24 formed radially outward from the vibration absorbing section 18, and restricts the radial displacement of the vibration absorbing section 18. Specifically, as the mount section 12 is displaced due to the vibration of the motor unit 2, the vibration absorbing section 18 deforms around the stud bolt 14, causing the outer peripheral surface of the restricting section 20, i.e., the outer peripheral surface 1a of the vibration damping member 1, to be pressed against the inner peripheral surface 12a of the mount section 12. As a result, the vibrations of the motor unit 2 are absorbed in the vibration absorbing section 18 via the mount section 12.
[0014] In this embodiment, the vibration absorbing section 18 of the vibration isolation member 1 forms a plurality of elastic sections that change in rigidity according to the amount of displacement of the displacement section 16. More specifically, the vibration absorbing section 18 has a plurality of hollow sections 26 drilled in the axial direction X of the stud bolt 14, and a plurality of solid sections 28 adjacent to the hollow sections 26 and functioning as the aforementioned elastic sections. The thickness and shape of the solid sections 28 are set according to the load received from the motor unit 2. More specifically, the vibration absorbing section 18 includes a plurality of columnar pillars 30 extending in the radial direction as solid sections 28 connecting the inner circumferential wall section 22 and the outer circumferential wall section 24.
[0015] Figure 3 shows a plan view of the mounting section 12. The pillars 30 are composed of multiple pairs adjacent to each other in the circumferential direction Y of the vibration absorbing section 18, and each pair of pillars 30 has a shape that is symmetrical with respect to the axis of symmetry A extending in the radial direction. In this embodiment, each pair of pillars 30 has a curved portion 30a at its central position in the radial direction, which is curved in a direction that is spaced apart from the axis of symmetry A. As a result, the hollow section 26 in this embodiment is formed alternately with roughly egg-shaped and roughly triangular shapes in plan view along the circumferential direction Y of the vibration absorbing section 18. Preferably, the number of sets of paired pillars 30 is a prime number, and in this embodiment, five sets of paired pillars 30 are provided.
[0016] Figure 4 is a graph showing the reaction force F of the vibration-damping member 1 with respect to the displacement amount D of the displacement part 16. Figure 4 shows graph L1 (solid line) of the vibration-damping member 1 of this embodiment and graph L2 (dotted line) of a conventional vibration-damping member formed only of a relatively rigid solid rubber material as a comparative example. Furthermore, the distribution of reaction force F in Figure 4 can be divided into region R1 during steady operation of the motor unit 2 and region R2 during startup of the motor unit 2, with reaction force F1 acting as a branching point as the boundary.
[0017] Conventional vibration-damping members are made only of relatively rigid solid rubber material, so high rigidity is maintained regardless of the magnitude of the displacement D of the displacement part 16. As a result, the reaction force F of the vibration-damping member increases exponentially with increasing displacement D of the displacement part 16, without distinction between regions R1 and R2. When the displacement D of the displacement part 16 exceeds a predetermined amount D1, the reaction force F of the vibration-damping member becomes maximum, in other words, all vibrations of the motor unit 2 received by the vibration-damping member are transmitted to the vehicle frame 3 without any damping. As a result, the occupants of the vehicle experience unpleasant vibrations, especially when the motor unit 2 is started.
[0018] On the one hand, in the region R1, the vibration isolation member 1 of the present embodiment receives a load in a state where each pillar 30 is stretched with respect to the displacement direction of the displacement portion 16. The shape, thickness, and material of each pillar 30 are adjusted to enable such stretching support. Specifically, for example, when the displacement portion 16 attempts to displace vertically downward, each pillar 30 located below the vibration absorption portion 18 is inclined with respect to the vertical direction, so that the vertically downward load received by each pillar 30 is resolved into a component force in the radial direction or the like other than the vertically downward direction. The resolved load flows to the regulation portion 20 and thus to the mount portion 12 and is received by these portions 20 and 12. Therefore, each pillar 30 has relatively little deformation, and the state shown in FIG. 3 is maintained. As a result, the reaction force F of the vibration isolation member 1 increases almost linearly (linearly) as the displacement amount D of the displacement portion 16 increases.
[0019] FIG. 5 shows a plan view of the mount portion 12 when the motor unit 2 is started. In the region R2 when the motor unit 2 is started, each pillar 30 located below the vibration absorption portion 18 gradually deforms so as to collapse at the curved portion 30a as shown in FIG. 5. At this time, the vertically downward load received by each pillar 30 is resolved into a component force in the horizontal direction or the like other than the vertically downward direction. The resolved load flows to the regulation portion 20 and thus to the mount portion 12 and is received by these portions 20 and 12.
[0020] On the other hand, each pillar 30 located above the vibration absorption portion 18 gradually undergoes tensile deformation so that the curved portion 30a is stretched. By the stretched pillars 30, the pillars 30 located below the vibration absorption portion 18 are pulled, and thereby, the vertically downward load received by the pillars 30 located below the vibration absorption portion 18 is reduced. As described above, although the pillars 30 located below the vibration absorption portion 18 undergo buckling deformation, the reaction force F of the vibration isolation member 1 also increases almost linearly as the displacement amount D of the displacement portion 16 increases until reaching a predetermined amount D2 in the region R2. Thus, unlike the conventional vibration isolation member, the vibration isolation member 1 of the present embodiment realizes the same vibration absorption characteristics as those during the steady operation of the motor unit 2 even when the motor unit 2 is started.
[0021] When the displacement amount D of the displacement portion 16 becomes equal to or greater than a predetermined amount D2, each pillar 30 located below the vibration absorption portion 18 is completely crushed and buckled at the bending portion 30a. As a result, each of these pillars 30 and the restricting portion 20 come into close contact and integrate with each other. Therefore, in the region where the amount is equal to or greater than the predetermined amount D2 in the region R2, the graph L1 of the vibration isolation member 1 becomes substantially parallel to the graph L2 of the conventional vibration isolation member. That is, in the region where the amount is equal to or greater than the predetermined amount D2 in the region R2, the reaction force F of the vibration isolation member 1 exponentially increases as the displacement amount D of the displacement portion 16 increases.
[0022] Unlike the conventional case, the vibration isolation member 1 of the present embodiment can extend the start of this exponential increase to the region where the amount is equal to or greater than the predetermined amount D2 in the region R2. Therefore, if the maximum value of the amplitude of the vibration that can occur from the motor unit 2 is preset to be less than the predetermined amount D2, the vibration of the motor unit 2 can be preferably buffered both during startup and steady operation of the motor unit 2, and the riding comfort of the passengers in the vehicle can be significantly improved. Thus, the vibration absorption portion 18 of the vibration isolation member 1 of the present embodiment is configured to be able to form a plurality of elastic portions that change to different rigidities by each pillar 30 according to the displacement amount D of the displacement portion 16.
[0023] As described above, the vibration isolation member 1 of the present embodiment includes the displacement portion 16, the vibration absorption portion 18, and the restricting portion 20 described above, and the vibration absorption portion 18 forms a plurality of elastic portions that change to different rigidities according to the displacement amount D of the displacement portion 16. Thereby, as described above, the vibration absorption characteristics of the vibration isolation member 1 can be changed according to the displacement amount D of the displacement portion 16 that is displaced according to the vibration from the motor unit 2. Therefore, the vibration of the motor unit 2 can be preferably buffered both during startup and steady operation of the motor unit 2, and the riding comfort of the passengers in the vehicle can be significantly improved.
[0024] Specifically, the vibration-damping member 1 is an elastic body molded from rubber material, and the stud bolts 14 of the vehicle frame 3 are connected to the displacement part 16 via sleeves 15. The vibration-absorbing part 18 has a plurality of hollow parts 26 drilled in the axial direction X of the stud bolts 14, and a plurality of solid parts 28 adjacent to the hollow parts 26 and functioning as the aforementioned elastic parts. The thickness and shape of the solid parts 28 are set according to the load received from the motor unit 2. Specifically, as described above, the thickness and shape of the solid parts 28, i.e., the pillars 30, should be set so that the maximum amplitude of the vibration received from the motor unit 2 is less than a predetermined amount D2 shown in Figure 5. This makes it possible to suitably dampen the vibration of the motor unit 2 both when the motor unit 2 is started and when it is running steadily.
[0025] More specifically, the vibration isolation member 1 is composed of an inner circumferential wall portion 22 which is a displacement portion 16, an outer circumferential wall portion 24 which is a restricting portion 20, and a plurality of column-shaped pillars 30 extending radially as solid portions 28 connecting the inner circumferential wall portion 22 and the outer circumferential wall portion 24. The pillars 30 are composed of a plurality of pairs adjacent to each other in the circumferential direction Y of the vibration absorption portion 18, and the paired pillars 30 have a shape that is symmetrical with respect to the axis of symmetry A that extends radially. As a result, when the load received by the paired pillars 30 is divided into forces, the load can be distributed as evenly as possible to each pillar. Therefore, when the paired pillars 30 deform, they can be deformed into as similar a shape as possible, so the vibration absorption characteristics of the vibration isolation member 1 can be easily adjusted according to the vibration characteristics of the motor unit 2.
[0026] Furthermore, each pair of pillars 30 has a curved portion 30a at its radial center that curves in a direction away from the axis of symmetry A. The aforementioned effect can be obtained if the pair of pillars 30 are symmetric with respect to the axis of symmetry A, so each pillar 30 may also be curved in a direction approaching the axis of symmetry A. However, by curving the curved portion 30a in a direction away from the axis of symmetry A, at least contact between the pillars 30 is avoided during the process of each pillar 30 collapsing and deforming. This delays the integration involving contact between the pillars 30, and consequently, the integration involving contact between each pillar 30 and the restricting portion 20. Therefore, it is possible to further effectively delay the start of the exponential increase in the reaction force F of the vibration-damping member 1 accompanying the increase in the displacement amount D of the displacement portion 16.
[0027] Furthermore, it is preferable that the number of pairs of pillars 30 be a prime number. For example, consider a case where pairs of pillars 30 are positioned radially opposite each other with respect to the axis of the vibration-damping member 1. In this case, the pairs of pillars 30 may resonate with each other due to vibration, and the amplitude of the vibration may be amplified. By making the number of pairs of pillars 30 a prime number, it is possible to prevent such amplification of amplitude caused by resonance between the pairs of pillars 30.
[0028] This concludes the description of embodiments of the present invention. However, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the invention. For example, the shape of the pillar 30 is not limited to the shape shown and described. However, for the reasons mentioned above, it is preferable that the pair of pillars 30 have a shape that is symmetrical with respect to the axis of symmetry A, and it is also preferable that the pillar 30 has a curved portion 30a that is curved in a direction away from the axis of symmetry A.
[0029] Furthermore, in the above embodiment, vibrations from the motor unit 2 are input to the outer peripheral wall portion 24 of the vibration-damping member 1 from the mount portion 12 formed on the motor unit 2. However, the vibration-damping member 1 of this embodiment can also be applied in an embodiment where vibrations from an operating device such as the motor unit 2 are input from the inner peripheral wall portion 22 of the vibration-damping member 1. Moreover, the vibration-damping member 1 of this embodiment can be used not only to absorb vibrations from the motor unit 2 that drives an electric vehicle, but also to absorb vibrations from the engine and vibrations from various other operating devices. [Explanation of symbols]
[0030] 1. Vibration-damping material (elastic body) 2. Motor unit (operating device) 3. Vehicle frame (support members) 14 Stud bolts (support bolts) 15 sleeves 16 Displacement part 18. Vibration absorption section 20 Regulatory Department 22 Inner peripheral wall 24 Outer wall 26 Hollow part 28. Solid part (elastic part) 30 Pillars (solid section, elastic section) 30a Curved section X-axis direction Y circumferential direction A axis of symmetry D Displacement
Claims
1. A vibration-damping member interposed between the operating device and its support member, which absorbs vibrations of the operating device, A displacement portion is formed in the radial center of the vibration-damping member and displaces in response to vibrations from the operating device, A vibration absorbing section is provided, which extends radially outward from the displacement section in the radial direction and absorbs the vibration, A restricting portion is formed on the radially outer side of the vibration absorbing portion and restricts the radial displacement of the vibration absorbing portion. Equipped with, The vibration absorbing section is a vibration-damping member that forms a plurality of elastic sections whose rigidity changes according to the amount of displacement of the displacement section.
2. The vibration-damping member according to claim 1, which is an elastic body molded from a rubber material.
3. The displacement portion is connected to the support member via a sleeve, The vibration absorbing section is Multiple hollow portions drilled in the axial direction of the support bolt, Adjacent to the hollow portion are a plurality of solid portions that function as the elastic portion. It has, The vibration-damping member according to claim 1 or 2, wherein the thickness and shape of the solid portion are set according to the load received from the operating device.
4. The inner circumferential wall portion which is the displacement portion, The outer periphery wall portion which is the restricting portion, The solid portion connecting the inner circumferential wall portion and the outer circumferential wall portion consists of a plurality of columnar pillars extending in the radial direction. The vibration-damping member according to claim 3, comprising the above.
5. The pillar is composed of multiple pairs of adjacent pillars in the circumferential direction of the vibration absorbing section. The vibration-damping member according to claim 4, wherein the pair of pillars have a shape that is symmetrical with respect to the axis of symmetry extending in the radial direction.
6. The vibration-damping member according to claim 5, wherein each pair of pillars has a curved portion at its central position in the radial direction, which is curved in a direction away from the axis of symmetry.
7. The vibration-damping member according to claim 5 or 6, wherein the number of pairs of pillars is a prime number.
8. The vibration-damping member according to claim 1, wherein the operating device is a motor unit for driving an electric vehicle.