JP7493437B2 - Anti-vibration device - Google Patents

Description

The present invention relates to vibration isolation devices used, for example, in engine mounts, motor mounts, and differential mounts in automobiles.

Conventionally, anti-vibration devices having a structure in which a first mounting member and a second mounting member are connected by a main rubber elastic body are known, and are used, for example, as mounts for vehicles. In addition, as in JP 2015-096754 A (Patent Document 1), an anti-vibration device has also been proposed in which an inner bracket is inserted from the side into a cylindrical portion provided on the first mounting member.

In some cases, the vibration isolation device is provided with a stopper mechanism that limits the amount of relative displacement between the first and second mounting members to improve the durability of the main rubber elastic body. In the structure of Patent Document 1, a stopper rubber is fixed to the outer circumferential surface of the cylindrical portion of the first mounting member, and the stopper mechanism is formed by the cylindrical portion of the first mounting member and the outer bracket fixed to the second mounting member abutting against each other via the stopper rubber.

JP 2015-096754 A

However, in Patent Document 1, when the distance between the cylindrical portion of the first mounting member and the outer bracket is limited due to restrictions on the installation space of the vibration isolation device, it may be difficult to ensure a sufficient thickness of the stopper rubber. In such a case, the spring constant of the stopper rubber increases suddenly due to compression caused by the input of the stopper load, and there is a risk of vibrations and shocks occurring due to the vibration isolation device suddenly becoming a high-dynamic spring.

The problem to be solved by this invention is to provide a vibration-proof device with a new structure that realizes soft spring characteristics when the stopper is in contact, and can prevent the occurrence of vibrations and shocks caused by a sudden high dynamic spring.

The following describes preferred embodiments for understanding the present invention. However, each embodiment described below is merely an example, and may be combined with one another as appropriate. The multiple components described in each embodiment may be recognized and used independently as far as possible, and may also be combined with any of the components described in another embodiment as appropriate. As a result, the present invention is not limited to the embodiments described below, and various alternative embodiments may be realized.

In a first aspect, a first mounting member having a tubular portion into which an inner bracket is inserted and fixed is connected to a second mounting member by a main rubber elastic body, and a stopper mechanism is formed that limits the amount of relative displacement between the first mounting member and the second mounting member by abutment between the first mounting member and the second mounting member via a stopper rubber fixed to the tubular portion, wherein an opening window penetrating the peripheral wall is formed in the tubular portion of the first mounting member, a filled rubber is fixed to the inner peripheral surface of the opening window to close the opening window, and a protruding rubber is provided that protrudes from the filled rubber toward the outer periphery of the tubular portion, and the stopper rubber is constituted by the filled rubber and the protruding rubber, and the area of a tip portion of the protruding rubber located on the opening window when projected in the penetration direction of the opening window is smaller than the area of the filled rubber , and the length dimension of the opening window in the axial direction of the tubular portion is greater than or equal to 1/3 and less than 4/5 of the length dimension of the tubular portion .

In a vibration-proof device constructed according to this embodiment, the size of the stopper rubber in the stopper contact direction is made larger by the amount of the filled rubber than when the stopper rubber is provided to protrude from the outer circumferential surface of the cylindrical portion. Therefore, the spring constant of the stopper rubber when it contacts the stopper is made smaller, and the occurrence of vibrations and shocks due to the sudden high dynamic spring when it contacts the stopper is avoided.

In the region where the opening window overlaps the projection in the penetration direction of the opening window, the area of the protruding rubber is made smaller than the area of the filled rubber, and the filled rubber has a relief portion that is positioned away from the protruding rubber. When the protruding rubber abuts against the second mounting member such as an outer bracket and the filled rubber is compressed, the relief portion allows the filled rubber to bulge and deform, so the filled rubber is less likely to enter a constrained state (dead rubber) where deformation is restricted within the opening window. This prevents a sudden increase in the spring constant of the filled rubber in response to compression of the stopper rubber, effectively improving the cushioning performance of the stopper rubber by the filled rubber, and preventing the occurrence of vibrations, impacts, etc.

In addition, with the vibration isolation device constructed according to this embodiment, the opening window is provided with a sufficient length in the cylindrical portion, which makes it easier to increase the area of the filled rubber placed inside the opening window, and therefore makes it possible to increase the area of the tip portion of the protruding rubber that constitutes the pressure-receiving surface of the stopper rubber. Since the opening window is not too long compared to the cylindrical portion, the reduction in strength of the cylindrical portion due to the formation of the opening window is suppressed, and damage to the cylindrical portion due to, for example, the insertion of an inner bracket is prevented.

In a second aspect, in the vibration-damping device described in the first aspect, the tubular portion is rectangular tubular, the opening window is provided in the side wall portion of the tubular portion, and the width dimension of the opening window in the circumferential direction of the tubular portion is at least half the width dimension of the side wall portion.

In a vibration-damping device constructed according to this embodiment, the opening window is provided in the side wall of the tubular section with a sufficiently large width, making it easier to obtain a large area for the filled rubber placed in the opening window, and therefore a large area can be obtained for the tip portion of the protruding rubber that constitutes the pressure-receiving surface of the stopper rubber.

In a third aspect, in the vibration isolation device according to the first or second aspect, the opening shape of the opening window is substantially rectangular.

An anti-vibration device constructed according to this embodiment can efficiently ensure a large opening area for the opening window compared to an opening window with a circular opening shape, etc. When using an opening window with a rectangular opening shape, it is desirable for the protruding rubber of the stopper rubber to also have a rectangular cross-section and protrude, ensuring a large pressure-receiving area for the stopper load while realizing the soft spring characteristics of the filled rubber.

A fourth aspect is an anti-vibration device described in any one of the first to third aspects, wherein the area of the tip portion of the protruding rubber located on the opening window when projected in the penetration direction of the opening window is at least half the area of the entire tip portion of the protruding rubber.

With an anti-vibration device constructed in accordance with this embodiment, more than half of the protruding rubber is positioned above the opening window, so that the portion of the stopper rubber located above the opening window, where it is easy to set soft spring characteristics due to the filled rubber, can contribute greatly to the spring characteristics of the entire stopper rubber.

The fifth aspect is an anti-vibration device described in any one of the first to fourth aspects, in which a fitting rubber is provided to cover the inner surface of the tubular portion, and the fitting rubber is integrally formed with the filling rubber to constitute the stopper rubber.

In a vibration isolation device constructed according to this embodiment, the inner circumferential surface of the cylindrical portion is covered with the fitting rubber, so that when the inner bracket is inserted and fixed to the cylindrical portion, the inner bracket is prevented from galling the cylindrical portion, making the assembly work easier. In addition, the height dimension of the stopper rubber in the input direction of the stopper load is made larger and easier to ensure by the filling rubber arranged in the opening window of the cylindrical portion, the protruding rubber arranged on the outer periphery of the cylindrical portion, and the fitting rubber arranged on the inner periphery of the cylindrical portion.

The present invention achieves soft spring characteristics when the stopper is in contact, preventing vibrations and shocks caused by a sudden high dynamic spring.

FIG. 1 is a perspective view showing an engine mount according to a first embodiment of the present invention in a state where a bracket is attached; FIG. 2 is a cross-sectional view of the engine mount with a bracket shown in FIG. 1, which corresponds to the cross-section II-II of FIG. 3 is a cross-sectional view taken along line III-III of FIG. IV-IV cross-sectional view of FIG. FIG. 2 is a perspective view of the engine mount shown in FIG. FIG. 6 is a perspective view of an inner shaft member constituting the engine mount shown in FIG. FIG. 7 is a right side view of the inner shaft member shown in FIG. 6 is a partial right side view of the engine mount shown in FIG. FIG. 1 is a partial right side view of an engine mount according to another embodiment of the present invention.

The following describes an embodiment of the present invention with reference to the drawings.

Figures 1 to 4 show an engine mount 10 for an automobile with brackets 56, 58, described below, attached as a first embodiment of a vibration isolation device constructed in accordance with the present invention. As also shown in Figure 5, the engine mount 10 has a structure in which a first mounting member 12 and a second mounting member 14 are elastically connected by a main rubber elastic body 16. In the following description, the up-down direction generally refers to the up-down direction in Figure 2, which is the mount axial direction, and the left-right direction generally refers to the left-right direction in Figure 2.

As shown in FIG. 6, the first mounting member 12 has a cylindrical portion 18 extending in the axis-perpendicular direction. The cylindrical portion 18 is generally rectangular. The peripheral wall of the cylindrical portion 18 has a pair of side walls 20, 20, an upper wall portion 22 connecting the upper ends of the side walls 20, 20, and a lower wall portion 24 connecting the lower ends of the side walls 20, 20. The side walls 20, 20, the upper wall portion 22, and the lower wall portion 24 are smoothly continuous without forming corners, and the cross-sectional shape of the cylindrical portion 18 in the axis-perpendicular direction is approximately rectangular with rounded corners. A circular hole is formed through the lower wall portion 24 of the cylindrical portion 18, and a cylindrical fixing portion 26 extending downward from the periphery of the circular hole is provided integrally with the cylindrical portion 18. The first mounting member 12, which has the cylindrical portion 18 and the fixing portion 26 as an integral part, can be obtained, for example, by pressing a metal plate.

As shown in Figs. 6 and 7, the cylindrical portion 18 has an opening window 28 penetrating the side wall portion 20. The opening window 28 penetrates the center portion of the side wall portion 20 in the opposing direction of the pair of side walls 20, 20 (the left-right direction perpendicular to the paper surface in Fig. 7). The opening window 28 has an approximately rectangular opening shape with rounded corners. The opening window 28 has a length dimension (the left-right dimension in Fig. 7, which is the axial direction of the cylindrical portion 18) L1 larger than the width dimension (the up-down dimension in Fig. 7, which is the circumferential direction of the cylindrical portion 18) W1. The length dimension L1 of the opening window 28 is preferably 1/3 or more and 4/5 or less than the axial length dimension L2 of the cylindrical portion 18. The width dimension W1 of the opening window 28 is preferably 1/2 or more than the width dimension W2 of the side wall portion 20 in the circumferential direction of the cylindrical portion 18. As a result, it is possible to obtain a large opening area for the opening window 28 while suppressing a decrease in the strength of the tubular portion 18 due to the formation of the opening window 28. In this embodiment, the opening window 28 is provided in each of the pair of side wall portions 20, 20, and the opening windows 28, 28 have approximately the same shape and size.

As shown in Figures 2 and 3, the second mounting member 14 is generally cylindrical, and has an inner flange-like portion 30 at its lower end that protrudes toward the inner circumference. The second mounting member 14 is disposed below the first mounting member 12 and generally on the same central axis, and the main rubber elastic body 16 is disposed between the first mounting member 12 and the second mounting member 14.

The main rubber elastic body 16 is generally frusto-conical in shape, with the upper portion, which is the smaller diameter side, vulcanization-bonded to the fastening portion 26 of the first mounting member 12, and the outer peripheral surface of the lower portion, which is the larger diameter side, vulcanization-bonded to the second mounting member 14. The main rubber elastic body 16 has a recess 32 that opens to the underside and decreases in diameter toward the top. The recess 32 is located below the fastening portion 26 of the first mounting member 12, and opens downward on the inner circumference of the inner flange-shaped portion 30 of the second mounting member 14.

A fitting rubber 34 that is integrally formed with the main rubber elastic body 16 is fixed to the inside of the first mounting member 12. The fitting rubber 34 covers the inner circumferential surface of the cylindrical portion 18 and fills the inner periphery of the fixing portion 26, and has a bracket mounting hole 36 that penetrates the inner periphery of the cylindrical portion 18.

An upper stopper rubber 38 is fixed to the upper wall 22 of the tubular portion 18 of the first mounting member 12. The upper stopper rubber 38 has a generally rectangular cross section and protrudes upward from the upper surface of the upper wall 22. The upper stopper rubber 38 has a tapered shape that gradually shrinks upward. A groove 40 is formed on the tip surface of the upper stopper rubber 38, which extends linearly in the axial direction of the tubular portion 18, and the unevenness of the tip surface caused by the groove 40 provides a cushioning effect when the stopper comes into contact, as described below.

A side stopper rubber 42 is fixed to the side wall 20 of the tubular portion 18 of the first mounting member 12. The side stopper rubber 42 includes a filling rubber 44 that is fixed to the inner peripheral surface of the opening window 28 to close the opening window 28, and a protruding rubber 46 that protrudes from the filling rubber 44 toward the outer periphery of the tubular portion 18.

The filling rubber 44 fills the inner circumference of the opening window 28. In this embodiment, the filling rubber 44 is integrally formed with the fitting rubber 34. The portion of the fitting rubber 34 that overlaps with the filling rubber 44 when projected in the penetration direction of the opening window 28 (left and right direction in FIG. 2) constitutes the side stopper rubber 42. In this embodiment, the filling rubber 44 fills the entire inner circumference area of the opening window 28, but may be thinner than the length of the opening window 28 in the penetration direction, for example.

The protruding rubber 46 is a rubber elastic body in the shape of a substantially rectangular block, and protrudes from the outer peripheral surface of the tubular portion 18 toward the outer periphery. In this embodiment, the protruding rubber 46 is substantially entirely located above the opening window 28 and is connected to the filling rubber 44. The protruding rubber 46 is provided on the outer surfaces of the pair of side wall portions 20, 20 in the opposing direction, and protrudes linearly toward the outside in the opposing direction of the pair of side wall portions 20, 20. The tip surface of the protruding rubber 46 is formed with a plurality of recessed grooves 48 extending in the axial direction of the tubular portion 18, and the unevenness of the tip surface caused by the recessed grooves 48 exerts a cushioning effect when the protruding rubber 46 abuts against a stopper, which will be described later.

The filling rubber 44, the protruding rubber 46, and the fitting rubber 34 constitute the side stopper rubber 42. The side stopper rubber 42 is provided penetrating the tubular portion 18 through the opening window 28, and the height dimension H in the penetrating direction of the opening window 28 is made large.

8 in the through-hole direction of the opening window 28 (left-right direction in FIG. 2), the area A of the tip portion of the protruding rubber 46 is smaller than the area B of the filling rubber 44. As a result, the filling rubber 44 has a pressure receiving portion 50 that overlaps with the tip portion of the protruding rubber 46 in the projection in the through-hole direction of the opening window 28, and a relief portion 52 that is located outside the pressure receiving portion 50. In this embodiment, the entire tip portion of the protruding rubber 46 that protrudes outward in the left-right direction from the covering rubber 54 described later is located on the opening of the opening window 28 in the projection in the through-hole direction of the opening window 28, so that the area A of the entire tip portion of the protruding rubber 46 is the same as the area of the portion of the tip portion of the protruding rubber 46 that is located on the opening window 28. For example, if the tip of the protruding rubber 46 spreads outwardly from the opening window 28 and the tip of the protruding rubber 46 is partially located above the opening window 28, the area of the part of the tip of the protruding rubber 46 that is located above the opening window 28 is smaller than the opening area B of the opening window 28, i.e., the area B of the filling rubber 44.

In this embodiment, the length dimension L3 of the tip portion of the protruding rubber 46 is smaller than the length dimension L1 of the opening window 28, and the width dimension W3 of the tip portion of the protruding rubber 46 is smaller than the width dimension W1 of the opening window 28. As a result, the filling rubber 44 that fills the opening window 28 has a relief portion 52 that does not overlap with the tip portion of the protruding rubber 46 when projected in the penetration direction of the opening window 28, and is continuously provided in a ring shape around the entire circumference of the opening window 28.

In this embodiment, the protruding rubber 46 has an inclined shape with the base end portion widening toward the base end, and a part of the widened portion is located outside the opening window 28. However, since the widened portion is not a portion that constitutes the stopper rubber when the stopper load acts, but is provided for the purpose of relieving stress concentration, the protruding rubber 46 can be considered to be substantially entirely located above the opening window 28. In addition, the widened portion of the protruding rubber 46 allows the relief portion 52 of the filling rubber 44 to bulge and deform when the stopper load is input, which will be described later.

The upper stopper rubber 38 and the side stopper rubber 42 are provided integrally with each other and are both formed integrally with the main rubber elastic body 16. That is, the covering rubber 54 formed integrally with the main rubber elastic body 16 is provided to cover the tubular portion 18, and the upper stopper rubber 38 and the side stopper rubber 42, including a part of the covering rubber 54, are integrally connected by the covering rubber 54. The upper stopper rubber 38 and the side stopper rubber 42 protrude toward the outer periphery of the tubular portion 18 more than the covering rubber 54, and the tip portion is located on the outer periphery of the tubular portion 18 more than the covering rubber 54. However, the upper stopper rubber 38 and the side stopper rubber 42 may be provided independently of each other, and may not be integral with the main rubber elastic body 16.

The engine mount 10 has a first mounting member 12 attached to a power unit (not shown) via an inner bracket 56, and a second mounting member 14 attached to a vehicle body (not shown) via an outer bracket 58.

The inner bracket 56 is a highly rigid member made of iron or the like, and as shown in Figs. 3 and 4, has a substantially rectangular rod-shaped fitting portion 60 and an attachment portion 62 integrally formed at one end of the fitting portion 60. The fitting portion 60 has an outer peripheral shape corresponding to the inner peripheral shape of the tubular portion 18, and is fixed to the tubular portion 18 of the first attachment member 12 by being inserted into the bracket mounting hole 36 of the fitting rubber 34. The attachment portion 62 has a plurality of bolt holes 64 that penetrate in the vertical direction, and is fixed to the power unit by bolts (not shown) that are inserted into the bolt holes 64.

The outer bracket 58 is a highly rigid member made of iron or the like, and includes a cylindrical mounting portion 66 that is fixed to the second mounting member 14, and a gate-shaped portion 68 that is fixed to the cylindrical mounting portion 66 by welding or other means. The gate-shaped portion 68 includes a pair of side legs 70, 70 that are fixed to the outer circumferential surface of the cylindrical mounting portion 66, and an upper connecting portion 72 that connects the upper ends of the side legs 70, 70 to each other. The pair of side legs 70, 70 each have an attachment piece 74 at their lower end, and are fixed to the vehicle body by a bolt (not shown) inserted through a bolt hole 76 that passes through the attachment piece 74. The upper connecting portion 72 of the gate-shaped portion 68 is arranged above the engine mount 10 attached to the cylindrical mounting portion 66, and the tip surface of the upper stopper rubber 38 faces the upper connecting portion 72 at a distance. The side legs 70, 70 of the gate-shaped portion 68 are arranged on both outer sides in the left-right direction facing the side wall portions 20, 20 of the cylindrical portion 18, and the tip surfaces of the side stopper rubbers 42, 42 face the side legs 70, 70 at a distance. The surface of the side legs 70 facing the side stopper rubber 42 is a plane that spreads approximately perpendicular to the left-right direction, and faces the tip surface of the protruding rubber 46 of the side stopper rubber 42 approximately parallel to the side. The gate-shaped portion 68 extends with a groove-shaped cross section, and at both ends in the groove width direction (left-right direction in FIG. 3), reinforcing ribs 77 that protrude outward and form the side walls of the groove-shaped cross section are provided, improving the load resistance of the gate-shaped portion 68 against the input of the stopper load. The reinforcing ribs 77 extend continuously to the mounting pieces 74, 74 provided at both ends of the gate-shaped portion 68.

When the engine mount 10 is attached to the vehicle, if vibrations to be damped are input in the vertical direction between the first mounting member 12 and the second mounting member 14, the main rubber elastic body 16 connecting the first mounting member 12 and the second mounting member 14 undergoes elastic deformation, and the desired vibration damping effect is achieved based on the energy damping effect caused by the internal friction of the main rubber elastic body 16 and the vibration isolation effect caused by the low dynamic spring.

When a significantly large amplitude vertical vibration is input and the first mounting member 12 is displaced significantly upward relative to the second mounting member 14, the upper wall portion 22 of the tubular portion 18 of the first mounting member 12 and the upper connecting portion 72 of the outer bracket 58 fixed to the second mounting member 14 indirectly come into contact with each other via the upper stopper rubber 38. This limits the relative displacement between the first mounting member 12 and the second mounting member 14, and prevents damage caused by excessive deformation of the main rubber elastic body 16. In this way, the upper stopper mechanism 78 of the engine mount 10, which limits the amount of upward relative displacement of the first mounting member 12 relative to the second mounting member 14 when mounted on the vehicle, is constituted by the abutment between the upper wall portion 22 of the tubular portion 18 and the upper connecting portion 72 of the outer bracket 58 via the upper stopper rubber 38.

In addition, when a vibration in the left-right direction with a significantly large amplitude is input and the first mounting member 12 is displaced significantly in the left-right direction relative to the second mounting member 14, the fitting portion 60 of the inner bracket 56 fitted to the cylindrical portion 18 of the first mounting member 12 and the side leg portion 70 of the outer bracket 58 fixed to the second mounting member 14 indirectly abut through the side stopper rubber 42. This limits the relative displacement between the first mounting member 12 and the second mounting member 14, and avoids damage due to excessive deformation of the main rubber elastic body 16. In this way, the side stopper mechanism 80 as a stopper mechanism that limits the relative displacement of the first mounting member 12 in the left-right direction relative to the second mounting member 14 is constituted by the abutment between the fitting portion 60 of the inner bracket 56 and the side leg portion 70 of the outer bracket 58 via the side stopper rubber 42. In this embodiment, the side stopper mechanism 80 is provided on both the left and right sides.

The side stopper rubber 42 constituting the side stopper mechanism 80 is provided through the opening window 28 of the cylindrical portion 18 and overlaps the fitting portion 60 of the inner bracket 56. Therefore, compared to the side stopper rubber of the conventional structure that is provided in an overlapping state on the outer surface of the side wall portion of the cylindrical portion, the height dimension H of the side stopper rubber 42 in the input direction of the stopper load is made larger by the amount of the filling rubber 44 and the fitting rubber 34. This makes it possible to reduce the spring constant of the side stopper rubber 42 at the initial input of the stopper load, and to realize soft spring characteristics of the side stopper rubber 42 at the initial contact. As a result, when the tip portion of the side stopper rubber 42 abuts against the outer bracket 58, a sudden change in the spring characteristics of the engine mount 10 is avoided, and the occurrence of vibration and impact at the time of stopper abutment is avoided.

The protruding rubber 46 of the side stopper rubber 42 has a contact area A of the tip portion with the outer bracket 58, projected in the penetration direction of the opening window 28 (the input direction of the stopper load), which is smaller than the area B of the filling rubber 44 filled in the opening window 28. As a result, the filling rubber 44 is provided with not only the pressure receiving portion 50 that constitutes the side stopper rubber 42 integrally with the protruding rubber 46, but also a relief portion 52 that is outside the pressure receiving portion 50. When the stopper load is input to the protruding rubber 46, the pressure receiving portion 50 is compressed in the input direction by the stopper load, and the pressure receiving portion 50 tries to bulge and deform in a direction perpendicular to the input direction of the stopper load. This bulging deformation of the pressure receiving portion 50 is permitted by the deformation of the relief portion 52 located around the pressure receiving portion 50, and the relief portion 52 bulges and deforms on the left and right outer surfaces, which are free surfaces. In short, by allowing the relief portion 52 to bulge and deform on the left and right outer surfaces, the spring constant of the pressure receiving portion 50 in the input direction of the stopper load is reduced, and the spring constant of the side stopper rubber 42 including the pressure receiving portion 50 is reduced. Therefore, when the side stopper rubber 42 abuts against the outer bracket 58, the side stopper rubber 42 with its small spring constant exerts an excellent cushioning effect, reducing vibration and impact at the time of abutment.

The side stopper rubber 42 of this embodiment has a larger height dimension H by including a portion of the fitting rubber 34, improving the cushioning performance. In addition, because the fitting rubber 34 is connected to the relief portion 52 of the filling rubber 44, the spring of the fitting rubber 34 is reduced in the same way as the pressure-receiving portion 50 of the filling rubber 44, and the excellent cushioning performance of the side stopper rubber 42 is effectively demonstrated.

Although the embodiments of the present invention have been described above in detail, the present invention is not limited to the specific description. For example, in the above embodiment, an example was shown in which the structure of the present invention is applied to the side stopper mechanism 80, but the structure of the present invention can also be applied to the upper stopper mechanism 78, for example.

The opening shape of the opening window 28 is not limited to a substantially rectangular shape, and may be, for example, a circle, a polygon other than a square, or an irregular shape. In addition, the cross-sectional shape of the stopper rubber 42 in a direction perpendicular to the protruding direction of the protruding rubber 46 is not limited to a substantially rectangular shape, and may be, for example, a circle, a polygon other than a square, or an irregular shape. Note that it is desirable for the opening shape of the opening window 28 and the cross-sectional shape in a direction perpendicular to the protruding direction of the protruding rubber 46 to correspond to each other, but they may be different shapes.

In the above embodiment, an example was shown in which the entire tip of the protruding rubber 46 is located on the opening window 28 in the projection in the penetration direction of the opening window 28, but for example, as shown in FIG. 9, the tip of the protruding rubber 46 may be located partially outside the opening window 28. In this case, the area A1 of the tip of the protruding rubber 46 located on the opening window 28 in the projection in the penetration direction of the opening window 28 is made smaller than the area B of the filling rubber 44 (the opening area of the opening window 28). In addition, it is desirable that the area A1 of the tip of the protruding rubber 46 located on the opening window 28 in the projection in the penetration direction of the opening window 28 is 1/2 times or more (A1 ≧ A/2) of the total area A. As a result, the influence of the part whose height dimension is secured by the filling rubber 44 and the fitting rubber 34 becomes large in the spring characteristic of the side stopper rubber 42, and soft spring characteristics can be realized. In addition, the area where the tip of the protruding rubber 46 is partially outside the opening window 28 makes it possible to expand the tuning range, including improving the stopper rigidity of the side stopper rubber 42. Note that in FIG. 9, the part of the tip of the protruding rubber 46 that is located above the opening window 28 is shown colored gray.

The protruding rubber can be tapered or stepped, as long as the area of the stopper contact surface at the tip of the protruding rubber is smaller than the area of the filled rubber. In this case, the bulging deformation of the relief portion of the filled rubber is tolerated by the portion of the protruding rubber that is outside the stopper contact surface and is less affected by the stopper load.

The contact surface of the outer bracket 58 with the protruding rubber 46 is not necessarily limited to a flat surface, and may be uneven, stepped, tapered, or the like. If the tip of the protruding rubber 46 partially contacts the contact surface at the beginning of the contact due to unevenness or the like on the contact surface on the second mounting member 14 side of the stopper mechanism 80, the contact area of the tip of the protruding rubber 46 that contacts the contact surface at the beginning of the contact is made smaller than the area of the filling rubber 44.

As shown in the above embodiment as the concave groove 48, the presence or absence of the unevenness for improving the initial impact characteristics such as cushioning and reducing the hitting sound provided at the tip of the protruding rubber 46 does not affect the area of the protruding tip. Similarly, the presence or absence of the widening of the base end portion of the protruding rubber 46 does not affect the area of the protruding tip of the protruding rubber 46. The area of the protruding tip of the protruding rubber 46 is the area of the region that is in contact with the second mounting member (outer bracket 58) when the stopper function begins to be exerted (the area of the region converted into the shape before deformation), and specifically, for example, it can be understood as the area of the contact area with the second mounting member in the linear region of the spring characteristic of the stopper rubber 42. It can also be specifically understood as the area of the contact area with the second mounting member when a load of 1/5 of the stopper input load planned or assumed in the stopper rubber 42 is input, or as the area of the contact area with the second mounting member in a deformed state of 1/5 of the maximum deformation amount allowed in the stopper rubber 42.

It is also desirable that the outer peripheral surface of the protruding rubber 46 does not have an overhang or undercut shape. Preferably, taking into account the taper, the outer peripheral surface of the protruding rubber 46 is inclined so that the cross section becomes slightly smaller in the protruding direction. In this way, it is preferable that the cross-sectional area of the protruding rubber 46 is the same as or larger than the area of the protruding tip portion.

In addition, the area of the filling rubber 44, which is made larger than the area of the tip portion of the protruding rubber 46, is desirably secured by an area located on the outer periphery of the tip portion of the protruding rubber 46 in the input direction of the stopper load to the protruding rubber 46 (or the penetration direction of the opening window 28 or the protruding direction of the protruding rubber 46). Specifically, as in the first embodiment, for example, when projected in the protruding direction of the protruding rubber 46, the filling rubber 44 (or the opening window 28) is made one size larger around the entire periphery of the tip portion of the protruding rubber 46, or, as in the other embodiment, for example, when projected in the protruding direction of the protruding rubber 46, the filling rubber 44 (or the opening window 28) is made partially larger around the tip portion of the protruding rubber 46 in a widened shape toward the outer periphery than the tip portion of the protruding rubber 46.

In the above embodiment, an example was shown in which only one opening window 28 was provided in the side wall portion 20 of the tubular portion 18, but for example, two or more opening windows 28 may be formed in the side wall portion 20. In this way, it is possible to obtain a large total opening area of the opening windows 28 while ensuring the deformation rigidity of the tubular portion 18.

The tubular portion 18 of the first mounting member 12 is not limited to a rectangular tube shape, and may be, for example, a cylindrical shape, a polygonal tube shape other than a rectangular tube, an irregular tube shape, etc. Also, the fitting rubber 34 fixed to the inner peripheral surface of the tubular portion 18 may not be necessary, and the inner bracket 56 may be directly pressed into the tubular portion 18 and fixed. In this case, the stopper rubber 42 is composed of the protruding rubber 46 and the filling rubber 44.

In the above embodiment, a solid-type vibration isolation device that does not have an internal fluid chamber or an active vibration control device has been exemplified, but the present invention can also be applied to, for example, a fluid-filled type vibration isolation device that has a fluid chamber in which a non-compressible fluid is sealed, or an active type fluid-filled type vibration isolation device that has an active vibration control device such as a vibrator.
Furthermore, the present invention originally includes each of the inventions described in (i) to (vi) below, and the configurations and effects thereof will be described below.
The present invention relates to
(i) A vibration-damping device in which a first mounting member having a tubular portion into which an inner bracket is inserted and fixed is connected to a second mounting member by a main rubber elastic body, and a stopper mechanism is formed that limits the amount of relative displacement between the first mounting member and the second mounting member by abutment between the first mounting member and the second mounting member via a stopper rubber fixed to the tubular portion, wherein an opening window penetrating a peripheral wall is formed in the tubular portion of the first mounting member, a filled rubber is fixed to the inner peripheral surface of the opening window to close the opening window, and a protruding rubber is provided that protrudes from the filled rubber towards the outer periphery of the tubular portion, the stopper rubber is constituted by the filled rubber and the protruding rubber, and the area of a tip portion of the protruding rubber located on the opening window when projected in the penetration direction of the opening window is smaller than the area of the filled rubber.
(ii) The vibration-proof device according to (i), wherein the length dimension of the opening window in the axial direction of the cylindrical portion is 1/3 to 4/5 times the length dimension of the cylindrical portion.
(iii) The vibration-proof device according to (ii), wherein the cylindrical portion is rectangular, the opening window is provided in a side wall portion of the cylindrical portion, and the width dimension of the opening window in the circumferential direction of the cylindrical portion is at least half the width dimension of the side wall portion.
(iv) The vibration-damping device according to any one of (i) to (iii), wherein the opening shape of the opening window is substantially rectangular.
(v) a vibration-damping device according to any one of (i) to (iv), in which the area of a tip portion of the protruding rubber located on the opening window when projected in the penetration direction of the opening window is at least half the area of the entire tip portion of the protruding rubber;
(vi) a fitting rubber is provided to cover the inner circumferential surface of the cylindrical portion;
The vibration-proof device according to any one of (i) to (v), wherein the fitting rubber is provided integrally with the filling rubber to constitute the stopper rubber;
This includes inventions relating to.
In the invention described in (i) above, the size of the stopper rubber in the stopper contact direction is made larger by the amount of the filled rubber than when the stopper rubber is provided to protrude from the outer circumferential surface of the cylindrical portion, so that the spring constant of the stopper rubber when it contacts the stopper is made smaller, and the occurrence of vibrations, shocks, etc. due to a sudden high dynamic spring when it contacts the stopper is avoided.
In the region where the opening window overlaps the projection in the penetration direction of the opening window, the area of the protruding rubber is smaller than the area of the filled rubber, and the filled rubber has a relief portion located away from the protruding rubber. When the protruding rubber abuts against the second mounting member such as an outer bracket and the filled rubber is compressed, the relief portion allows the filled rubber to bulge and deform, so the filled rubber is unlikely to be in a restricted state (dead rubber) where deformation is restricted within the opening window. Therefore, a sudden increase in the spring constant of the filled rubber due to compression of the stopper rubber is prevented, and the filled rubber effectively improves the cushioning performance of the stopper rubber, preventing the occurrence of vibrations, impacts, etc.
In the invention described in (ii) above, by providing the opening window with a sufficient length in the cylindrical portion, it becomes easier to obtain a large area for the filled rubber disposed within the opening window, and it becomes possible to obtain a large area for the tip portion of the protruding rubber that constitutes the pressure receiving surface of the stopper rubber. Since the opening window is not too long compared to the cylindrical portion, a decrease in the strength of the cylindrical portion due to the formation of the opening window is suppressed, and damage to the cylindrical portion due to, for example, the insertion of an inner bracket is prevented.
In the invention described in (iii) above, the opening window is provided with a sufficiently large width dimension in the side wall portion of the tubular portion, making it easier to obtain a large area for the filled rubber placed within the opening window, and thereby making it possible to obtain a large area for the tip portion of the protruding rubber that constitutes the pressure-receiving surface of the stopper rubber.
In the invention described in (iv) above, a large opening area of the opening window can be efficiently ensured compared to an opening window whose opening shape is circular, etc. When an opening window whose opening shape is rectangular is adopted, it is preferable that the protruding rubber of the stopper rubber also has a shape that protrudes with a rectangular cross section, and a large pressure receiving area for the stopper load can be ensured while realizing soft spring characteristics by the filled rubber.
In the invention described in (v) above, more than half of the protruding rubber is located above the opening window, so that the portion of the stopper rubber located above the opening window, where it is easy to set soft spring characteristics using the filled rubber, can be made to contribute significantly to the spring characteristics of the entire stopper rubber.
In the invention described in (vi) above, since the inner peripheral surface of the cylindrical portion is covered with the fitting rubber, when the inner bracket is inserted and fixed to the cylindrical portion, the inner bracket is prevented from galling the cylindrical portion, making the assembly work easier. Also, the height dimension of the stopper rubber in the input direction of the stopper load can be made larger by the filling rubber arranged in the opening window of the cylindrical portion, the protruding rubber arranged on the outer periphery of the cylindrical portion, and the fitting rubber arranged on the inner periphery of the cylindrical portion.

10 Engine mount (vibration isolation device)
Reference Signs List 12: First mounting member 14: Second mounting member 16: Main rubber elastic body 18: Cylindrical portion 20: Side wall portion 22: Upper wall portion 24: Lower wall portion 26: Fixing portion 28: Opening window 30: Inner flange-shaped portion 32: Recess 34: Fitting rubber 36: Bracket mounting hole 38: Upper stopper rubber 40: Recessed groove 42: Side stopper rubber (stopper rubber)
44 Filling rubber 46 Protruding rubber 48 Groove 50 Pressure receiving portion 52 Relief portion 54 Covering rubber 56 Inner bracket 58 Outer bracket 60 Fitting portion 62 Mounting portion 64 Bolt hole 66 Cylindrical mounting portion 68 Gate-shaped portion 70 Side leg portion 72 Upper connecting portion 74 Mounting piece 76 Bolt hole 77 Reinforcing rib 78 Upper stopper mechanism 80 Side stopper mechanism (stopper mechanism)

Claims (5)

a first mounting member having a tubular portion into which an inner bracket is inserted and fixed, the first mounting member being connected to a second mounting member by a main rubber elastic body;
a stopper mechanism that limits a relative displacement amount between the first mounting member and the second mounting member by abutment between the first mounting member and the second mounting member via a stopper rubber fixed to the cylindrical portion,
an opening window penetrating a peripheral wall of the cylindrical portion of the first mounting member;
a filling rubber is provided which is fixed to an inner peripheral surface of the opening window to close the opening window, and a protruding rubber is provided which protrudes from the filling rubber towards an outer periphery of the cylindrical portion, the filling rubber and the protruding rubber comprising the stopper rubber;
The area of the tip portion of the protruding rubber located on the opening window when projected in the penetrating direction of the opening window is smaller than the area of the filling rubber ,
A vibration-isolating device , wherein the length dimension of the opening window in the axial direction of the cylindrical portion is greater than or equal to 1/3 and less than or equal to 4/5 of the length dimension of the cylindrical portion . 2. The vibration-damping device of claim 1, wherein the cylindrical portion is rectangular, the opening window is provided in the side wall portion of the cylindrical portion, and the width dimension of the opening window in the circumferential direction of the cylindrical portion is at least half the width dimension of the side wall portion. 3. The vibration isolation device according to claim 1, wherein the opening shape of the opening window is substantially rectangular. 4. The vibration-isolating device according to claim 1, wherein the area of the tip portion of the protruding rubber located on the opening window when projected in the penetration direction of the opening window is at least half the area of the entire tip portion of the protruding rubber. A fitting rubber is provided to cover the inner circumferential surface of the cylindrical portion,
5. The vibration-isolating device according to claim 1 , wherein the fitting rubber is provided integrally with the filling rubber to constitute the stopper rubber.

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