Cylindrical mount

Abstract

To provide a cylindrical mount having a novel structure which can improve durability against a large load input to a separation side of an inner member and an outer cylinder member in an axial direction, and can further improve a degree of freedom of the tuning of a characteristic with respect to a load input to an approach side in the axial direction.SOLUTION: In a cylindrical mount 10 in which an inner member 12 and an outer cylinder member 14 are connected to each other by a cylindrical main-body rubber elastic body 16, the inner member 12 comprises a cup member 44 which is opened toward the main-body rubber elastic body 16, one end part of the main-body rubber elastic body 16 in an axial direction is pushed in and attached to the cup member 44, a bottom wall 46 of the cup member 44 is laminated on, but not adhered to, one end face of the main-body rubber elastic body 16 in the axial direction, a peripheral wall 48 of the cup member 44 is spread toward an opening side, and the peripheral wall 48 is made to function as an externally-fit deformation regulation part 56 with a clearance 58 in a state of being separated to an external periphery with respect to the main-body rubber elastic body 16 in at least at an opening portion.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a cylindrical mount applied to a cab mount, a power unit mount, etc. of an automobile.

Background Art

[0002] Conventionally, a cylindrical mount in which an inner member and an outer cylindrical member are connected by a cylindrical body rubber elastic body has been known. For example, Japanese Patent Application Laid-Open No. 2018-071768 (Patent Document 1) discloses that a plate-like first mounting member constituting an inner member is fixed to one end surface in the axial direction of a cylindrical body rubber elastic body, and a second mounting member (outer cylindrical member) is fixed to the outer peripheral surface of the body rubber elastic 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, in the structure of Patent Document 1, when a large load in the axial direction in which the first mounting member is separated from the second mounting member is input, tensile stress may occur in the body rubber elastic body. Therefore, for example, when a large load input in the separation direction between the first mounting member and the second mounting member is assumed, it is preferable to further improve the durability.

[0005] Furthermore, even when a load is applied between the first and second mounting members in a direction that brings them closer together in the axial direction, it may be required to have, for example, good vibration isolation performance due to low spring characteristics in the initial stage when the input load is relatively small, and a limiting effect (including a stopper effect) on the amount of compression of the main rubber elastic body due to high dynamic spring characteristics when a large load is applied. For this reason, it is preferable to further improve the degree of freedom in tuning the characteristics according to the input load, even when a load is applied in the direction that brings the first and second mounting members closer together.

[0006] The problem to be solved by the present invention is to provide a novel cylindrical mount structure that improves the durability against large load inputs on the axial separation side of the inner member and outer cylindrical member, and further improves the degree of freedom in tuning the characteristics against load inputs on the axial approach side. [Means for solving the problem]

[0007] The following describes preferred embodiments for understanding the present invention. However, each embodiment described below is illustrative and can be combined with others as appropriate. Furthermore, the multiple components described in each embodiment can be recognized and adopted as independently as possible, and can be combined with any component described in another embodiment as appropriate. Thus, the present invention is not limited to the embodiments described below, and various other embodiments can be realized.

[0008] The first embodiment is a cylindrical mount in which an inner member and an outer cylindrical member are connected by a cylindrical main body rubber elastic body, wherein the inner member has a cup member that opens toward the main body rubber elastic body, one axial end of the main body rubber elastic body is inserted into and attached to the cup member, and the bottom wall of the cup member is non-adhesively superimposed on one axial end face of the main body rubber elastic body, and the peripheral wall of the cup member A step is provided in the axial middle portion, and the opening side is greater than the step. Expand towards the opening and the Main body: rubber elastic material of outer perimeter on It is considered a deformation-restricting part that is extrapolated with a gap. Furthermore, the inner circumferential surface of the main rubber elastic body is in close contact with the outer circumferential surface of the inner member throughout, from the portion to which the deformation restricting portion is externally fitted to the outer cylindrical member to the portion to which it is internally fitted to the outer cylindrical member, and the outer circumferential surface of the main rubber elastic body is continuously expanding in diameter toward the outer cylindrical member, from the portion to which the deformation restricting portion is externally fitted to the outer cylindrical member to the entire portion extending axially toward the outer cylindrical member. They exist.

[0009] In the cylindrical mount structure according to this embodiment, the bottom wall of the cup member is not adhered to the main rubber elastic body, thereby improving the durability of the main rubber elastic body against axial input (tensile input) on the side where the inner member and outer cylindrical member are separated from each other.

[0010] Because the peripheral wall of the cup member has an expanded shape, the gap between the peripheral wall and the main rubber elastic body is small at the bottom side of the peripheral wall, and the deformation of the main rubber elastic body is restrained at the bottom side of the peripheral wall, ensuring an appropriate initial spring. Furthermore, at the opening side of the peripheral wall, deformation of the main rubber elastic body is allowed to a certain extent to obtain an initial low spring characteristic, while the amount of deformation of the main rubber elastic body is limited by contact with the deformation restricting part. This makes it possible to achieve a two-stage spring characteristic (low spring at the beginning of input and high spring later in input) and to improve the durability of the main rubber elastic body through a stopper action.

[0011] The second embodiment is a cylindrical mount as described in the first embodiment, wherein the peripheral wall of the cup member is a stepped cylindrical shape with a step in the middle, the part of the peripheral wall on the opening side of the step is the deformation restricting part, and the part of the peripheral wall on the bottom side of the step is a proximity part that is closer to the outer surface of the main rubber elastic body than the deformation restricting part.

[0012] According to the cylindrical mount structure in this embodiment, the stepped cylindrical cup member's peripheral wall allows for initial spring tuning in the proximity section while limiting the amount of deformation of the main rubber elastic body in the deformation-restricting section. Furthermore, the spring tuning described above can be easily and accurately performed by adjusting the size of the step provided in the peripheral wall of the cup member.

[0013] The third embodiment is a cylindrical mount as described in the first or second embodiment, wherein the deformation-restricting portion of the cup member has a tapered shape that increases in diameter from the bottom side to the opening side.

[0014] According to the cylindrical mount structure in this embodiment, the deformation-restricting portion of the peripheral wall of the cup member is tapered, which facilitates the attachment of the cup member to the main rubber elastic body. Furthermore, the separation distance between the deformation-restricting portion and the outer surface of the main rubber elastic body can be adjusted by changing the taper angle of the deformation-restricting portion.

[0015] The fourth embodiment is a cylindrical mount described in any one of the first to third embodiments, wherein the open end of the cup member is provided with a flange-shaped stopper portion that protrudes outward, and the stopper portion is positioned axially opposite to a mounting plate portion provided on the outer cylindrical member.

[0016] According to the cylindrical mount structure in this embodiment, in addition to the stopper action by the deformation restricting portion, a stopper action is also exerted by the contact between the stopper portion and the mounting plate portion, thereby providing a multi-stage stopper action (spring characteristics).

[0017] The fifth embodiment is a cylindrical mount described in any one of the first to fourth embodiments, wherein the main body rubber elastic body has a groove formed therein that opens to one axial end face where the bottom wall of the cup member overlaps, and the end of the groove opens to the outer circumferential surface of the main body rubber elastic body.

[0018] According to the cylindrical mount structure in this embodiment, it is possible to prevent the generation of abnormal noise when the cup member and the main body rubber elastic body separate from each other or come into contact from a separated state due to axial input.

[0019] The sixth embodiment is a cylindrical mount as described in the fifth embodiment, wherein the bottom end of the peripheral wall is a mounting portion that overlaps with the outer circumferential surface of the main rubber elastic body, and the groove depth dimension at the end of the recessed groove that opens to the outer circumferential surface of the main rubber elastic body is greater than the axial height dimension of the mounting portion.

[0020] According to the cylindrical mount structured according to this aspect, it is possible to prevent the outer peripheral opening of the concave groove from being blocked by the mounting portion, and to stably obtain the effect of preventing abnormal noise.

[0021] The seventh aspect is the cylindrical mount according to any one of the first to sixth aspects, wherein a shaft member is fixed to the inner peripheral surface of the main body rubber elastic body, and the cup member is fixed to the shaft member to constitute the inner member.

[0022] According to the cylindrical mount structured according to this aspect, by fixing the cup member to the shaft member fixed to the main body rubber elastic body, even if the cup member is attached to the main body rubber elastic body in a non-adhesive manner, for example, during transportation or storage, it is possible to prevent the cup member from coming off the main body rubber elastic body or shifting in position.

[0023] The eighth aspect is the cylindrical mount according to the seventh aspect, wherein the main body rubber elastic body is pre-compressed between the cup member and the outer cylinder member by fixing the cup member to the shaft member.

[0024] According to the cylindrical mount structured according to this aspect, by fixing the cup member to the shaft member, the main body rubber elastic body can be pre-compressed by the cup member attached to the main body rubber elastic body in a non-adhesive manner. Further, since the main body rubber elastic body is pre-compressed, for example, it is difficult for the main body rubber elastic body and the bottom wall of the cup fitting to be separated during tensile input, and the generation of abnormal noise is prevented.

[0025] The ninth aspect is the cylindrical mount according to the seventh or eighth aspect, wherein a concave groove that opens at one end surface in the axial direction where the bottom wall of the cup member is overlapped is formed in the main body rubber elastic body, and the concave groove includes an annular groove portion that extends annularly around the shaft member and an outer peripheral groove portion that extends from the annular groove portion toward the outer periphery and opens to the outer peripheral surface of the main body rubber elastic body.

[0026] According to the cylindrical mount structure in this embodiment, the recessed groove having an annular groove and an outer circumferential groove can more effectively prevent the generation of abnormal noise. Furthermore, when the main rubber elastic body is vulcanized and bonded to the shaft member, the area to which the main rubber elastic body is fixed to the shaft member can be defined by the mold by overlapping the mold for molding the main rubber elastic body with the shaft member within the annular groove. [Effects of the Invention]

[0027] According to the present invention, in a cylindrical mount, the durability against large load inputs on the axial separation side of the inner member and the outer cylindrical member is improved, and the degree of freedom in tuning the characteristics against load inputs on the axial approach side is further improved. [Brief explanation of the drawing]

[0028] [Figure 1] This is a cross-sectional view showing a cab mount as a first embodiment of the present invention, corresponding to cross-section II in Figure 2. [Figure 2] Plan view of the cab mount shown in Figure 1 [Figure 3] Figure 1 shows an exploded perspective view of the cab mount. [Figure 4] Figure 1 shows a vertical cross-sectional view of the cab mount with an axial compressive load applied. [Modes for carrying out the invention]

[0029] Embodiments of the present invention will be described below with reference to the drawings.

[0030] Figures 1 and 2 show a cab mount 10 for an automobile as a first embodiment of a cylindrical mount structure according to the present invention. The cab mount 10 has a structure in which a main rubber elastic body 16 is disposed between an inner member 12 and an outer cylindrical member 14. In the following description, the vertical direction generally refers to the vertical direction in Figure 1, which is the mount axis direction.

[0031] The inner member 12 includes a shaft member 18. The shaft member 18 is a small-diameter, substantially cylindrical shape and extends linearly in the vertical direction. The shaft member 18 is formed from, for example, a metal such as iron or aluminum alloy, or a fiber-reinforced synthetic resin.

[0032] An outer cylindrical member 14 is arranged to surround the outer circumference of the shaft member 18. The outer cylindrical member 14 integrally comprises a substantially cylindrical cylindrical portion 20 and a mounting plate portion 22 that protrudes outward from the upper end of the cylindrical portion 20. The cylindrical portion 20 has a substantially cylindrical shape with an inner diameter larger than the outer diameter of the shaft member 18, and an inner flange-like portion 24 that protrudes inward is integrally formed at its lower end. In this embodiment, the mounting plate portion 22 is substantially disc-shaped and has a substantially constant structure around its entire circumference, but for example, mounting structures to the vehicle body, such as mounting bolts and bolt holes, may be provided at multiple locations in the circumferential direction. If such mounting structures are provided, the mounting plate portion 22 may protrude significantly outward in the circumferential direction in the portion where the mounting structure is provided. In short, the mounting plate portion 22 in this embodiment is merely an example and can be appropriately modified according to the mounting structure to the vehicle body, etc. The outer cylindrical member 14 can be obtained, for example, as a pressed metal fitting in which a cylindrical portion 20 and a mounting plate portion 22 are integrally formed.

[0033] The shaft member 18 is inserted through the outer cylindrical member 14, and the main rubber elastic body 16 is positioned between the shaft member 18 and the outer cylindrical member 14. The main rubber elastic body 16 is cylindrical in shape as a whole, with its inner circumferential surface vulcanized and bonded to the shaft member 18, and its lower circumferential surface 26 vulcanized and bonded to the cylindrical portion 20 of the outer cylindrical member 14. As shown in Figure 3, the main rubber elastic body 16 is an integrally vulcanized molded product 28 comprising the shaft member 18 and the outer cylindrical member 14.

[0034] The upper part 30 of the main rubber elastic body 16, located above the cylindrical portion 20 of the outer cylindrical member 14, is cylindrical in shape with a larger diameter than the cylindrical portion 20. The outer circumferential surface of the upper part 30 is an inclined outer circumferential surface 32 that increases in diameter downwards. In this embodiment, the inclined outer circumferential surface 32 is linearly inclined at a substantially constant angle, but the angle of inclination of the inclined outer circumferential surface 32 may change gradually or in steps in the vertical direction. An annular plate-shaped cushioning rubber 34 protruding outwards is provided at the lower end of the upper part 30, and a large fixing area to the outer cylindrical member 14 is secured by fixing the cushioning rubber 34 to the upper surface of the mounting plate portion 22.

[0035] As shown in Figures 1 and 3, a groove 36 opening to the upper surface is provided at the upper end of the main rubber elastic body 16. The groove 36 opens to the outer circumferential surface of the main rubber elastic body 16. The groove 36 is composed of an annular groove portion 38 extending circumferentially from the inner circumferential end of the main rubber elastic body 16, and four outer circumferential groove portions 40, 40, 40, 40 extending radially outward from four locations in the circumferential direction of the annular groove portion 38.

[0036] The annular groove 38 extends circumferentially around the shaft member 18, which is positioned on the inner circumference of the main rubber elastic body 16. Because the annular groove 38 is provided in the main rubber elastic body 16, the upper end of the shaft member 18 is exposed from the main rubber elastic body 16.

[0037] The outer circumferential groove 40 extends linearly in the radial direction of the main rubber elastic body 16, its inner circumference is connected to the annular groove 38, and its outer circumference end opens to the outer surface of the main rubber elastic body 16. The inner circumferential portion of the outer circumferential groove 40 has a depth dimension that is approximately the same as that of the annular groove 38, while the depth dimension is increased at the outer circumference end. In this embodiment, when the cab mount 10 is in a standalone state before being mounted on the vehicle, the depth dimension at the outer circumference end of the outer circumferential groove 40 is greater than the axial distance between the bottom wall 46 and the step 52, and the groove bottom at the outer circumference end of the outer circumferential groove 40 is located axially below the step 52 of the peripheral wall 48 (towards the opening side of the peripheral wall 48). Preferably, even when the cab mount 10 is mounted on the vehicle and a support load is applied, the groove bottom at the outer circumference end of the outer circumferential groove 40 is located axially below the step 52. The groove width dimension of the outer circumferential groove 40 is smaller than the groove width dimension of the annular groove 38.

[0038] As shown in Figure 3, the upper end of the main rubber elastic body 16 is located on the outer circumference side of the annular groove 38 and has four upper end protrusions 42, 42, 42, 42 which are divided in the circumferential direction by four outer circumference grooves 40, 40, 40, 40.

[0039] As shown in Figures 1 and 3, the upper end, which is one axial end of the main rubber elastic body 16, is inserted into the cup member 44 that constitutes the inner member 12. The cup member 44 is a rotating body with a concave cross-section that opens downward toward the main rubber elastic body 16, and integrally comprises an annular plate-shaped bottom wall 46 and a cylindrical peripheral wall 48 that protrudes downward from the outer peripheral end of the bottom wall 46. The cup member 44 can be obtained, for example, by press-forming a metal sheet.

[0040] The bottom wall 46 of the cup member 44 is provided with a connecting cylindrical portion 50 that protrudes downward from its inner peripheral edge. The outer diameter of the connecting cylindrical portion 50 is slightly larger than the inner diameter of the shaft member 18, and as shown in Figure 2, it is fixed to the shaft member 18 by being fitted into the upper opening of the shaft member 18. In this way, the cup member 44 is fixed to the shaft member 18, and the shaft member 18 and the cup member 44 constitute the inner member 12. Furthermore, because the cup member 44 is fixed to the shaft member 18, the bottom wall 46 of the cup member 44 is pressed against the upper surface of the main rubber elastic body 16 without adhesive, and the main rubber elastic body 16 is pre-compressed axially between the outer cylindrical member 14 and the cup member 44. The spring characteristics of the main rubber elastic body 16 are tuned by the pre-compression of the main rubber elastic body 16. Furthermore, at least one of the inner peripheral edge of the upper opening of the shaft member 18 and the outer peripheral edge of the protruding tip of the connecting cylinder portion 50 is chamfered to allow the connecting cylinder portion 50 to be fitted into the shaft member 18.

[0041] The peripheral wall 48 of the cup member 44 is a stepped cylindrical shape with a step 52 in the middle of the vertical direction, and has an expanding shape that becomes larger in diameter toward the opening side. The peripheral wall 48 has a proximity portion 54 with a smaller diameter toward the bottom wall 46 side of the step 52, and a deformation restricting portion 56 with a larger diameter toward the opening side of the step 52. In this embodiment, the step 52 is inclined downward toward the outer circumference, but for example, it may spread in a direction approximately perpendicular to the axis. The position of the step 52 in the depth direction of the cup member 44 can be adjusted according to the required characteristics, but in this embodiment, the step 52 in the depth direction of the cup member 44 is provided toward the bottom wall 46 side from the center, and a large volume of the gap 58 is secured, thereby avoiding excessive deformation suppression of the upper part 30 of the main rubber elastic body 16 and securing a nonlinear compressive deformation region in the axial direction.

[0042] The proximity portion 54 constitutes the end of the peripheral wall 48 on the bottom wall 46 side. The proximity portion 54 has an inner diameter that is approximately the same as the outer diameter of the upper end of the main rubber elastic body 16, and the upper end projections 42,42,42,42 that constitute the upper end of the main rubber elastic body 16 are inserted into the proximity portion 54. In this embodiment, the proximity portion 54 has a tapered shape that corresponds to the outer peripheral surface of the upper part 30 of the main rubber elastic body 16, and the outer peripheral surfaces of the upper end projections 42,42,42,42 are superimposed on the inner peripheral surface of the proximity portion 54 with approximately zero contact, so that the proximity portion 54 is the mounting portion of this embodiment. However, the outer peripheral surfaces of the upper end projections 42,42,42,42 may be pressed against the inner peripheral surface of the proximity portion 54 and in close contact, or there may be a gap between them and the surface. The groove depth dimension at the outer peripheral end of the outer peripheral groove 40 is greater than the axial height dimension of the adjacent portion 54, and when the cup member 44 is attached to the main rubber elastic body 16, the opening of the outer peripheral groove 40 on the outer peripheral surface of the main rubber elastic body 16 opens to the inner circumference of the deformation restricting portion 56 below the adjacent portion 54.

[0043] The deformation restricting portion 56 constitutes the end on the opening side of the peripheral wall 48. The deformation restricting portion 56 has an inner diameter that is larger than the outer diameter of the upper part 30 of the main rubber elastic body 16, and is positioned externally on the outer circumference side of the upper part 30 of the main rubber elastic body 16, forming a gap 58 between it and the main rubber elastic body 16. The proximity portion 54 is positioned closer to the outer circumferential surface of the upper part 30 of the main rubber elastic body 16 than the deformation restricting portion 56. The deformation restricting portion 56 extends downward integrally from the outer circumferential end of the step 52. The deformation restricting portion 56 has a tapered cylindrical shape that becomes larger in diameter from the bottom wall 46 side to the downward opening side. A flange-shaped stopper portion 60 that protrudes outward is integrally formed at the lower end of the deformation restricting portion 56 that constitutes the opening end of the cup member 44. The stopper portion 60 spreads out in a direction approximately perpendicular to the axis and is positioned facing upward relative to the mounting plate portion 22 of the outer cylindrical member 14. The stopper portion 60 is positioned above and separated from the cushioning rubber 34 fixed to the mounting plate portion 22.

[0044] The cab mount 10, which has a structure in which a cup member 44 is attached to an integrally vulcanized molded product 28, is attached, for example, by mounting bolts (not shown) inserted through the inner member 12 to the automobile cabin 62, which is superimposed on the upper surface of the bottom wall 46 of the cup member 44. The outer cylindrical member 14 has a mounting plate portion 22 which is attached to the automobile frame 64 by the above-described mounting structure (not shown). As a result, the cab mount 10 is interposed between the automobile cabin 62 and the frame 64, and the cabin 62 is vibration-damped and connected to the frame 64.

[0045] When a load (tensile load) is applied to the cab mount 10 in a direction that separates the cabin 62 and the frame 64 from each other, the cup member 44 and the outer cylindrical member 14 of the inner member 12 of the cab mount 10 are displaced axially apart from each other. Since the cup member 44 is attached to the main rubber elastic body 16 without being fixed, it is capable of relative upward displacement with respect to the main rubber elastic body 16. Therefore, no axial tensile load is applied to the main rubber elastic body 16, and the durability of the main rubber elastic body 16 is improved.

[0046] In this embodiment, since the cup member 44 is fixed to the shaft member 18, the main rubber elastic body 16 is pre-compressed in the axial direction. Therefore, when a tensile load is applied, the bottom wall 46 of the cup member 44 is less likely to separate from the upper surface of the main rubber elastic body 16. Consequently, even if a compressive load is applied after a tensile load, the bottom wall 46 of the cup member 44 will not strike the upper surface of the main rubber elastic body 16 from a separated state, thus preventing the generation of a striking sound.

[0047] When a load is applied to the cab mount 10 in a direction that brings the cabin 62 and frame 64 closer together, the cup member 44 and outer cylindrical member 14 of the inner member 12 of the cab mount 10 are displaced axially toward each other. As a result, the main rubber elastic body 16 is compressed in the axial direction, and vibration damping effects such as vibration damping based on the internal friction of the main rubber elastic body 16 are exerted.

[0048] When the input load in the compressive direction is large, the amount of compressive deformation of the main rubber elastic body 16 is limited by the stopper mechanism. The cab mount 10 has a first stopper mechanism and a second stopper mechanism, and a stepwise stopper action is exerted.

[0049] The first stopper mechanism is formed by the contact between the outer circumferential surface of the upper part 30 of the main rubber elastic body 16 and the deformation restricting portion 56 of the peripheral wall 48 of the cup member 44. That is, when the main rubber elastic body 16 is compressed in the axial direction, it undergoes bulging deformation in the direction perpendicular to the axis based on Poisson's ratio. However, since the inner circumferential surface is constrained by the shaft member 18, the outer circumferential surface of the upper part 30, which is a free surface, deforms to bulge outwards into the gap 58 on the outer side. As shown in Figure 4, the upper part 30 of the main rubber elastic body 16, which has bulged outwards to fill the gap 58, is constrained by the contact of its outer circumferential surface with the deformation restricting portion 56 of the cup member 44, thereby limiting the amount of bulging deformation outwards. As a result, the axial compression spring of the main rubber elastic body 16 becomes stiffer, and a stopper action is exerted to limit the amount of axial compression deformation of the main rubber elastic body 16. Furthermore, as the amount of bulging deformation toward the outer circumference of the upper part 30 of the main rubber elastic body 16 increases, the contact area with the deformation restricting part 56 increases, and the axial compression spring of the main rubber elastic body 16 becomes stiffer. As a result, the stopper action of the first stopper mechanism that limits the axial compression deformation of the main rubber elastic body 16 is exerted more strongly.

[0050] The peripheral wall 48 of the cup member 44 is shaped to expand toward the opening, and the deformation restricting portion 56 that constitutes the opening of the peripheral wall 48 is positioned with a gap 58 between it and the main rubber elastic body 16. Therefore, in the initial deformation stage when the amount of compressive deformation of the main rubber elastic body 16 is small, the outer peripheral surface of the upper part 30 of the main rubber elastic body 16 becomes a free surface separated inward from the peripheral wall 48 of the cup member 44 below the upper end projection 42, and the vibration damping effect due to the low spring characteristics of the main rubber elastic body 16 is exhibited. On the other hand, when the amount of compressive deformation of the main rubber elastic body 16 increases, the outer peripheral surface of the upper part 30 of the main rubber elastic body 16 abuts against the peripheral wall 48 of the cup member 44 even below the upper end projection 42, and is restrained, thus exhibiting a stopper effect. In this way, the spring characteristics of the main rubber elastic body 16 are adjusted according to the magnitude of the input compressive load, making it possible to achieve both the desired vibration damping performance and durability performance.

[0051] The second stopper mechanism is formed by the contact between the mounting plate portion 22 of the outer cylindrical member 14 and the stopper portion 60 of the cup member 44. That is, when the main rubber elastic body 16 is compressed and deformed in the axial direction, the cup member 44 approaches the outer cylindrical member 14 in the axial direction. As the amount of compressive deformation of the main rubber elastic body 16 increases, the mounting plate portion 22 of the outer cylindrical member 14 and the stopper portion 60 of the cup member 44 come into contact via the buffer rubber 34. This limits the approaching displacement between the outer cylindrical member 14 and the cup member 44, thereby exerting a stopper effect that limits the amount of axial compressive deformation of the main rubber elastic body 16.

[0052] In this embodiment, the stopping action of the first stopper mechanism is exerted at a stage where the amount of compression deformation of the main rubber elastic body 16 is smaller than that of the stopping action of the second stopper mechanism. In this way, by having the stopping action of the first stopper mechanism and the stopping action of the second stopper mechanism exerted in stages, it is possible to prevent shocks caused by abrupt changes in spring characteristics and achieve a good ride comfort, while effectively limiting the amount of compression deformation of the main rubber elastic body 16 and ensuring the durability of the main rubber elastic body 16.

[0053] Since the cup member 44 is attached to the main rubber elastic body 16 without being fixed, when an axial compression load is applied, the bottom wall 46 of the cup member 44 is pressed against the upper surface of the main rubber elastic body 16, which may cause abnormal noise due to the close contact between the bottom wall 46 and the upper surface of the main rubber elastic body 16. Therefore, in this embodiment, an annular groove 38 and an outer peripheral groove 40 are formed on the upper surface of the main rubber elastic body 16, dividing the upper surface of the main rubber elastic body 16 into four sections, which prevents the bottom wall 46 from continuously contacting the upper surface of the main rubber elastic body 16 over a wide area. This prevents abnormal noise when the bottom wall 46 of the cup member 44 and the upper surface of the main rubber elastic body 16 are in close contact.

[0054] Furthermore, in a structure in which the cup member 44 and the main rubber elastic body 16 are not fixed together, there is a risk of abnormal noise being generated when the bottom wall 46 of the cup member 44 and the upper surface of the main rubber elastic body 16 separate from their close contact state. However, since the groove 36 that opens onto the upper surface of the main rubber elastic body 16 is formed on the outer circumferential surface of the main rubber elastic body 16, abnormal noise during separation is also prevented.

[0055] Although embodiments of the present invention have been described in detail above, the present invention is not limited by its specific description. For example, in the above embodiment, the peripheral wall 48 of the cup member 44 was configured such that the opening side of the step 52 had a larger diameter than the bottom wall 46 side, and was a tapered cylindrical shape that widened toward the opening. However, the peripheral wall of the cup member does not need to have both a step 52 and a tapered shape, as long as it has an expanding shape with a larger diameter toward the opening. In short, the peripheral wall of the cup member may, for example, have a step and a deformation restricting portion extending axially with a substantially constant diameter, or it may have a structure without a step, where the deformation restricting portion is a tapered cylindrical shape that widens toward the opening. Taking into consideration the required nonlinear characteristics, for example, multiple steps 52 with a larger inclination angle than other parts of the peripheral wall may be provided in the axial direction of the peripheral wall.

[0056] The inner member does not necessarily have to include a shaft member 18, and may consist only of a cup member 44. In this case, mounting bolts or the like inserted into the inner circumference of the main rubber elastic body 16 may perform at least some of the functions of the shaft member 18, such as limiting the bulging deformation of the main rubber elastic body 16 toward the inner circumference.

[0057] The connection structure between the shaft member 18 and the cup member 44 is not particularly limited. For example, the shaft member 18 may be press-fitted and fixed into the central hole of the bottom wall 46 of the cup member 44, or the inner peripheral edge of the bottom wall 46 may be crimped and fixed to the axial end of the shaft member 18.

[0058] The upper end portion of the main rubber elastic body 16 may be press-fitted into the adjacent portion 54 of the cup member 44, or it may be in contact without press-fitting, or it may be separated from the inner circumference of the adjacent portion 54. In the latter case, a gap is provided not only between the upper part 30 of the main rubber elastic body 16 and the deformation restricting portion 56 on the peripheral wall 48 of the cup member 44, but also between it and the adjacent portion 54. In this case, the radial dimension of the gap on the inner circumference of the adjacent portion 54 is smaller than the radial dimension of the deformation restricting portion 56 on the inner circumference. Alternatively, for example, when a support load such as the cabin 62 is applied to the cylindrical mount 10 while the vehicle is mounted, the upper part 30 of the main rubber elastic body 16 may elastically deform, causing the upper part 30 of the main rubber elastic body 16 to come into contact with the adjacent portion 54. Thus, even when the entire peripheral wall 48 is separated from the main rubber elastic body 16 toward the outer circumference, the separation distance between the peripheral wall 48 and the main rubber elastic body 16 differs between the bottom wall 46 side and the opening side, thereby achieving both soft spring characteristics for small input loads and stiff spring characteristics for large input loads.

[0059] For example, in the embodiment, the gap 58 was formed continuously with a substantially constant size around the entire circumference, but it is also possible to make the size of the gap 58 different in the circumferential direction, taking into consideration the required vibration damping characteristics and load characteristics. For example, if different load-spring characteristics are required in two directions perpendicular to the axis, namely the longitudinal direction of the vehicle and the lateral direction of the vehicle, the radial size of the gap 58 may be made different in the direction perpendicular to the axis by making the outer circumference shape of the upper part 30 elliptical or making the circumferential wall 48 elliptical, for example, the gap 58 or step 52 may be substantially eliminated in one direction perpendicular to the axis.

[0060] In the above embodiment, the groove 36 was composed of an annular groove portion 38 extending in the circumferential direction and an outer peripheral groove portion 40 extending radially in the radial direction. However, the groove only needs to open to the outer peripheral surface of the main rubber elastic body 16, and can be composed of, for example, a groove portion extending perpendicular to the axis.

[0061] The cylindrical mount according to the present invention is not only applicable to cab mounts, but can also be applied to power unit mounts that vibration-damping connect power units, including engines and motors, to the vehicle body, for example. Furthermore, the present invention originally encompasses all of the inventions described in (i) to (ix) below, and its structure and effects are noted below. The present invention (i) A cylindrical mount in which an inner member and an outer cylindrical member are connected by a cylindrical main body rubber elastic body, wherein the inner member includes a cup member that opens toward the main body rubber elastic body, one axial end of the main body rubber elastic body is inserted into and attached to the cup member, the bottom wall of the cup member is non-adhesively superimposed on one axial end face of the main body rubber elastic body, the peripheral wall of the cup member expands toward the opening side, and the peripheral wall is a deformation restricting portion that is fitted onto the main body rubber elastic body with a gap at least at the opening, away from the outer circumference, (ii) The cylindrical mount as described in (i), wherein the peripheral wall of the cup member is a stepped cylindrical shape with a step in the middle, the part of the peripheral wall on the opening side of the step is the deformation restricting part, and the part of the peripheral wall on the bottom side of the step is a proximity part that is closer to the outer surface of the main rubber elastic body than the deformation restricting part, (iii) The deformation restricting portion of the cup member is tapered in shape, with the diameter increasing from the bottom side to the opening side, as described in (i) or (ii), (iv) The opening end of the cup member is provided with a flange-shaped stopper portion that protrudes outward, and the stopper portion is positioned axially opposite to the mounting plate portion provided on the outer cylindrical member, as described in any one of (i) to (iii). (v) The main body rubber elastic body has a groove formed in it that opens to one axial end face where the bottom wall of the cup member overlaps, and the end of the groove opens to the outer circumferential surface of the main body rubber elastic body, the cylindrical mount according to any one of (i) to (iv), (vi) The cylindrical mount described in (v), wherein the bottom end of the peripheral wall is a mounting portion that overlaps with the outer surface of the main rubber elastic body, and the groove depth dimension of the end of the recessed groove that opens to the outer surface of the main rubber elastic body is greater than the axial height dimension of the mounting portion, (vii) The cylindrical mount described in any one of (i) to (vi), wherein a shaft member is fixed to the inner circumferential surface of the main rubber elastic body, and the inner member is formed by fixing the cup member to the shaft member. (viii) The cylindrical mount according to (vii), wherein the cup member is fixed to the shaft member so that the main body rubber elastic body is pre-compressed between the cup member and the outer cylindrical member, (ix) The main body rubber elastic body has a groove formed in it that opens to one axial end face where the bottom wall of the cup member overlaps, and the groove includes an annular groove portion that extends in an annular shape around the shaft member and an outer groove portion that extends outward from the annular groove portion and opens to the outer surface of the main body rubber elastic body, the cylindrical mount as described in (vii) or (viii), This includes inventions relating to the present invention. In the invention described in (i) above, the bottom wall of the cup member is not adhered to the main rubber elastic body, thereby improving the durability of the main rubber elastic body against axial input (tensile input) on the side where the inner member and outer cylindrical member are separated from each other. Because the peripheral wall of the cup member has an expanding shape, the gap with the main rubber elastic body is small at the bottom side of the peripheral wall, and the deformation of the main rubber elastic body is restrained at the bottom side of the peripheral wall, ensuring an appropriate initial spring. Furthermore, on the opening side of the peripheral wall, deformation of the main rubber elastic body is allowed to a certain extent to obtain an initial low spring characteristic, while the amount of deformation of the main rubber elastic body is limited by contact with the deformation restricting part, thereby realizing a two-stage spring characteristic (low spring at the beginning of input and high spring at the end of input) or improving the durability of the main rubber elastic body through a stopper action. In the invention described in (ii) above, the stepped cylindrical cup member's peripheral wall allows for initial spring tuning in the proximity portion while limiting the amount of deformation of the main rubber elastic body in the deformation-restricting portion. Furthermore, the spring tuning described above can be easily and accurately performed by adjusting the size of the step provided in the peripheral wall of the cup member. In the invention described in (iii) above, the deformation-restricting portion of the peripheral wall of the cup member is tapered, which facilitates the attachment of the cup member to the main rubber elastic body. Furthermore, the separation distance between the deformation-restricting portion and the outer surface of the main rubber elastic body can be adjusted by changing the taper angle of the deformation-restricting portion. In the invention described in (iv) above, in addition to the stopper action by the deformation restricting portion, a stopper action is also exerted by the contact between the stopper portion and the mounting plate portion, so that a multi-stage stopper action (spring characteristics) can be obtained. In the invention described in (v) above, it is possible to prevent the generation of abnormal noise when the cup member and the main body rubber elastic body separate from each other or come into contact from a separated state due to axial input. In the invention described in (vi) above, the outer peripheral opening of the groove is prevented from being blocked by the mounting part, thereby providing a stable noise prevention effect. In the invention described in (vii) above, by fixing the cup member to the shaft member fixed to the main rubber elastic body, even if the cup member is attached to the main rubber elastic body without adhesive, it is possible to prevent the cup member from coming off the main rubber elastic body or shifting position during transportation or storage, for example. In the invention described in (viii) above, by fixing the cup member to the shaft member, the main body rubber elastic body can be pre-compressed by the cup member, which is attached to the main body rubber elastic body without adhesive. Furthermore, because the main body rubber elastic body is pre-compressed, for example, separation between the main body rubber elastic body and the bottom wall of the cup fitting is less likely to occur when tensile input is applied, thereby preventing the generation of abnormal noise. In the invention described in (ix) above, the recessed groove having an annular groove and an outer circumferential groove can more effectively prevent the generation of abnormal noise. Furthermore, when the main rubber elastic body is vulcanized and bonded to the shaft member, the area to which the main rubber elastic body is fixed to the shaft member can be defined by the mold by overlapping the mold for molding the main rubber elastic body with the shaft member within the annular groove. [Explanation of symbols]

[0062] 10. Carburetor mount (cylindrical mount) 12 Inner component 14 Outer cylindrical member 16 Main body rubber elastic body 18 Shaft member 20 Cylindrical part 22 Mounting plate section 24 Inner flange-like portion 26 Lower 28 One-piece vulcanized molded product 30 Top 32 Inclined outer surface 34 cushioning rubber 36 grooves 38 Annular groove 40 Outer perimeter groove 42 Upper end protrusion 44 Cup component 46 Bottom wall 48 Peripheral wall 50 Connecting cylinder part 52 steps 54 Proximity part (attachment part) 56 Deformation Control Section 58 gaps 60 Stopper part 62 cabins 64 frames

Claims

1. In a cylindrical mount in which an inner member and an outer cylindrical member are connected by a cylindrical main body rubber elastic material, The inner member comprises a cup member that opens toward the main body rubber elastic body, One axial end of the main rubber elastic body is inserted into the cup member and attached, and the bottom wall of the cup member is non-adhesively superimposed on the axial end face of the main rubber elastic body. The peripheral wall of the cup member has a step in the axial middle portion, and the part on the opening side of the step expands toward the opening side and is fitted onto the outer surface of the main rubber elastic body with a gap, forming a deformation restricting portion. The inner circumferential surface of the main rubber elastic body is in close contact with the outer circumferential surface of the inner member throughout, from the portion to which the deformation restricting portion is externally fitted to the outer cylindrical member to the portion to which it is internally fitted to the outer cylindrical member. The outer surface of the main body rubber elastic body is a cylindrical mount in which the entire portion extending axially from the part to which the deformation restricting part is fitted toward the outer cylindrical member continuously expands in diameter toward the outer cylindrical member.

2. The peripheral wall of the cup member is formed into a stepped cylindrical shape with a step in the middle, The part of the peripheral wall on the opening side of the step is designated as the deformation restricting portion. The cylindrical mount according to claim 1, wherein the lower side of the peripheral wall below the step is a proximity portion that is closer to the outer surface of the main body rubber elastic material than the deformation restricting portion.

3. The cylindrical mount according to claim 1 or 2, wherein the deformation-restricting portion of the cup member has a tapered shape that increases in diameter from the bottom side to the opening side.

4. The cylindrical mount according to claim 1 or 2, wherein the open end of the cup member is provided with a flange-shaped stopper portion that protrudes outward, and the stopper portion is arranged to face in the axial direction with respect to a mounting plate portion provided on the outer cylindrical member.

5. The cylindrical mount according to claim 1 or 2, wherein the main body rubber elastic body has a groove formed therein that opens to one axial end face where the bottom wall of the cup member overlaps, and the end of the groove opens to the outer circumferential surface of the main body rubber elastic body.

6. The bottom end of the peripheral wall is a mounting portion that overlaps with the outer surface of the main rubber elastic body. The cylindrical mount according to claim 5, wherein the groove depth dimension at the end of the recessed groove opening on the outer circumferential surface of the main rubber elastic body is greater than the axial height dimension of the mounting portion.

7. The cylindrical mount according to claim 1 or 2, wherein a shaft member is fixed to the inner circumferential surface of the main body rubber elastic body, and the inner member is formed by fixing the cup member to the shaft member.

8. The cylindrical mount according to claim 7, wherein the main body rubber elastic body is pre-compressed between the cup member and the outer cylindrical member by fixing the cup member to the shaft member.

9. The main body rubber elastic material has a groove formed in it that opens to one axial end face where the bottom walls of the cup members overlap. The cylindrical mount according to claim 7, wherein the groove includes an annular groove portion extending in an annular shape around the shaft member and an outer groove portion extending outward from the annular groove portion and opening to the outer surface of the main rubber elastic body.

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