JP6257353B2 - Stabilizer bush - Google Patents

Description

  The present invention relates to a stabilizer bush for supporting a stabilizer bar on a vehicle body, a frame or the like in a vibration-proof manner.

  Conventionally, a vehicle such as an automobile is provided with a stabilizer bar for suppressing the inclination of the vehicle body when turning. In general, the stabilizer bar is supported on the body, the frame, or the like of the vehicle via a stabilizer bush. A stabilizer bush for supporting the stabilizer bar on a vehicle in a vibration-proof manner generally includes a cylindrical rubber elastic body having a central hole penetrating in the axial direction. It can be attached to a vehicle body or the like via a bracket attached to the surface.

  By the way, in such a stabilizer bush, the cylindrical rubber elastic body is elastically deformed when a load is input, so that the outer peripheral surface of the stabilizer bar inserted into the central hole of the cylindrical rubber elastic body and the cylindrical rubber elastic body are If a gap is formed between the inner peripheral surface of the center hole, foreign matter such as muddy water may enter the gap from the axial end. If foreign matter enters between the cylindrical rubber elastic body and the stabilizer bar, the durability may be reduced due to wear or noise may be caused.

  Therefore, in order to prevent the generation of a gap between the cylindrical rubber elastic body and the stabilizer bar, the cylindrical rubber elastic body is given radial pre-compression by increasing the tightening force applied to the outer peripheral surface by the bracket. ing. Furthermore, as shown in Japanese Patent Application Laid-Open No. 2000-46110 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2004-257540 (Patent Document 2), an interling member made of a hard material such as metal is used as a cylindrical rubber elastic member. The cylindrical rubber elastic body abuts against the outer peripheral surface of the stabilizer bar by partitioning the cylindrical rubber elastic body into an inner peripheral rubber portion and an outer peripheral rubber portion by being fixed in the middle of the body in the thickness direction. A structure has also been proposed in which the gap is made uniform over the entire circumference and the generation of a gap due to a local decrease in the contact force is suppressed.

  However, if the cylindrical rubber elastic body is subjected to a large radial pre-compression and is brought into close contact with the outer peripheral surface of the stabilizer bar with a large contact force, the spring characteristics in the torsional direction and the axis perpendicular direction of the stabilizer bush become hard. The ride comfort of the vehicle may be reduced. In addition, if the entire center hole of the stabilizer bush is brought into close contact with the outer peripheral surface of the stabilizer bar with a large abutting force, there is a problem that a large squeak or rubbing noise due to stick slip is likely to occur when the stabilizer bar is torsionally deformed. It was.

  In order to cope with such a problem, it has been proposed to adhere the central hole of the cylindrical rubber elastic body to the stabilizer bar over the entire surface, but it is special for pretreatment such as cation coating and adhesion treatment. There is a problem that a process is required, and design conditions such as a degree of freedom in selecting a rubber material may be limited as the generated stress and strain of the cylindrical rubber elastic body increase. Further, at both axial end portions of the cylindrical rubber elastic body, annular seal rubber protrusions protruding toward the inner peripheral surface side of the center hole may be provided to seal the openings at both axial end portions of the cylindrical rubber elastic body. Although it is conceivable, it is difficult to obtain a stable sealing effect over a long period of time with a simple rubber seal protrusion. In addition, since the stabilizer bush is arranged in front of the vehicle, the rubber seal protrusion is easy due to the impact of foreign matter such as gravel. There was also a risk of damage.

JP 2000-46110 A JP 2004-257540 A

  Here, the present invention has been made in the background as described above, and the problem to be solved is a stabilizer bar while ensuring basic performance such as vibration proofing and durability required. It is an object of the present invention to provide a stabilizer bush having a novel structure capable of effectively and stably preventing intrusion of foreign matters into and between them.

A first aspect of the present invention made to solve such a problem is a cylindrical rubber elastic body having a central hole through which a stabilizer bar is inserted, and an intermediate portion in the thickness direction of the cylindrical rubber elastic body. In a stabilizer bush configured to include an interling member that is fixedly disposed so as to partition the cylindrical rubber elastic body into an inner peripheral rubber portion and an outer peripheral rubber portion, the diameter dimension of the interling member is an axis. Small diameter portions are provided on both sides in the axial direction of the large diameter portion that is different in the direction and provided in the axial intermediate portion, and the radial thickness of the inner peripheral rubber portion is larger than the inner peripheral portion of the large diameter portion. Also, since the inner peripheral portion of the small diameter portion is made smaller, the radial compression rate of the inner peripheral rubber portion in the attached state to the stabilizer bar is smaller than the axial intermediate portion. What has been enlarged in And features.

  In the stabilizer bushing of this aspect, the compression ratio of the inner peripheral rubber portion that comes into contact with and closely contacts the stabilizer bar by the small diameter portions provided at both axial end portions of the interling member is larger than that of the central portion in the axial direction. It is enlarged at both ends in the axial direction. As a result, a large contact force against the stabilizer bar can be secured at both axial end portions where the gap between the stabilizer bar is easy to open, and the gap between the stabilizer bar and the stabilizer bar can be prevented. Intrusion of foreign matter such as muddy water into the water can be effectively prevented.

  In addition, in the axially intermediate portion, the radial compression ratio in the inner peripheral rubber portion is reduced, so that the spring characteristics of the stabilizer bush as a whole, such as the torsional direction and the axis perpendicular direction, may become excessively hard. By avoiding this, it is possible to achieve an excellent ride comfort with good vibration isolation performance.

  In addition, since both end portions in the axial direction of the cylindrical rubber elastic body are backed up and held entirely by the small diameter portion of the interling member disposed on the outer peripheral side, the cylindrical rubber elastic body is compared with a seal lip made of a simple rubber protrusion. Thus, good sealing performance can be exhibited with excellent durability.

  In this aspect, the material of the interling member is not particularly limited, but a metal harder than the cylindrical rubber elastic body in order to back up the cylindrical rubber elastic body and efficiently exert a reinforcing action. And synthetic resins are preferred. In addition, the region between the small diameter portion and the large diameter portion of the interling member may be a stepped shape extending in the direction perpendicular to the axis, but it is a tapered shape that gradually changes in diameter by a predetermined length in the axial direction. Is preferred. In particular, when press-working using a metal interling member, the thickness between the small-diameter part and the large-diameter part is tapered so that the member thickness dimension is substantially constant and the strength is easily secured. Become.

  Further, the interling member only needs to be disposed extending in the axial direction of the cylindrical rubber elastic body, and may be divided in the circumferential direction. For example, it may be composed of a plurality of arcuate plate-shaped divided bodies by being divided at a plurality of locations on the circumference. In particular, in order to allow the stabilizer bush to be attached to the stabilizer bar from the side (the direction perpendicular to the axis), a dividing portion that expands at one location on the circumference is provided to form a substantially C-shaped cross-sectional structure. In this case, it is desirable that the cylindrical rubber elastic body can be easily bent by dividing the interling member even at the central portion on the circumference facing the dividing portion in the radial direction.

According to a second aspect of the present invention, in the stabilizer bush according to the first aspect, a cross section in which the inner diameter dimension of the center hole is substantially constant over the entire length in the axial direction in a free state before being attached to the stabilizer bar. It is a shape.

  In the stabilizer bush having the structure according to this aspect, the cylindrical rubber elastic body can be easily molded and attached to the stabilizer bar, and a local protrusion or the like is provided on the inner peripheral surface of the cylindrical rubber elastic body. Concentration of stress and strain due to this can be avoided, and further excellent durability can be obtained.

According to a third aspect of the present invention, there is provided the stabilizer bush according to the first or second aspect, wherein the central portion of the large-diameter portion of the interring member is in a free state before being attached to the stabilizer bar. A large-diameter straight portion extending at a constant diameter is provided, and a small-diameter straight portion extending at a constant diameter is provided at the opening-side axial end of the small-diameter portion.

  In the stabilizer bush having the structure according to the present embodiment, the inner peripheral rubber portion provided on the inner peripheral side of each of the large-diameter straight portion and the small-diameter straight portion in a state of being attached to the stabilizer bar has a substantially constant radial direction. Compression. Thereby, in each inner peripheral rubber part, stress and distortion are dispersed in a wide range, and a stable spring characteristic is exhibited.

According to a fourth aspect of the present invention, there is provided the stabilizer bush according to any one of the first to third aspects, wherein the shaft of the small-diameter portion in the interling member is in a free state before being attached to the stabilizer bar. The length in the direction is 3 mm or more and 30% or less of the total axial length of the interling member.

  In the stabilizer bush configured according to this aspect, the seal structure that can more effectively suppress the gap even when a load is input in the direction of twisting or twisting by setting the axial length of the small diameter portion to 3 mm or more. It can be secured at the opening portions at both ends in the axial direction of the center hole. In addition, if the axial length of the small diameter part exceeds 30%, the hard spring characteristics in the small diameter part are more dominant than the spring characteristics in the large diameter part, and the radial tightening becomes stronger when mounted on the stabilizer bar. Therefore, the spring characteristics against twisting and torsion tend to be too stiff, and even when attached to the stabilizer bar from the side as a C-shaped cross-sectional shape, the C-shaped opening portion may be widened and it may be difficult to install. .

  In this embodiment, the axial length of the interling member is substantially equal to the axial length of the cylindrical rubber elastic body. In addition, the axial length of the small diameter portion of the interling member is more preferably 5 mm or more and 20% or less of the total axial length.

A fifth aspect of the present invention is the stabilizer bush according to any one of the first to fourth aspects, in a free state before being attached to the stabilizer bar, in the interling member, the large diameter portion and The radial dimension difference from the small diameter portion is set within a range of 1 to 3 mm.

  In the stabilizer bush having the structure according to this aspect, by setting the radial dimension difference between the large diameter portion and the small diameter portion to 1 to 3 mm, each inner circumference in the small diameter portion and the large diameter portion when mounted on the stabilizer bar. The radial compression ratio of the rubber portion can be set in an appropriate range, and it becomes easy to easily achieve both the sealing performance at the axial end portions of the center hole and the required spring characteristics within a practical range. That is, when the radial dimension difference between the large diameter portion and the small diameter portion is out of the range of 1 to 3 mm, the radial compression rate in the inner peripheral rubber portion is in one of the large diameter portion and the small diameter portion in the mounted state on the stabilizer bar. There is a risk that it will be too large or too small, which makes it difficult to achieve both the required sealing performance and spring characteristics.

  In this aspect, the radial dimension difference between the large diameter portion and the small diameter portion is more preferably set in the range of 1.5 to 2 mm. Further, in the characteristic range required for a general stabilizer bush, it is desirable that the radial thickness of the inner peripheral rubber portion be 5 to 10 mm on the inner peripheral side of the large diameter portion, and more preferably 7 Set to ~ 8 mm.

  According to the stabilizer bush having the structure according to the present invention, it is possible to effectively prevent foreign matters from entering between the stabilizer bar and the cylindrical rubber elastic body, and to ensure good riding comfort of the vehicle. In addition, when the interling member is formed of a material harder than the cylindrical rubber elastic body, the reinforcing effect of the seal portion in the cylindrical rubber elastic body by the interling member is also exhibited, and the sealing performance and durability are improved. A compatible stabilizer bush can be realized.

The perspective view which shows the stabilizer bush as one Embodiment of this invention. The top view of the stabilizer bush shown by FIG. The front view of the stabilizer bush shown by FIG. The left view of the stabilizer bush shown by FIG. VV sectional drawing in FIG. VI-VI sectional drawing in FIG. VII-VII sectional drawing in FIG. The top view of the interling member which comprises the stabilizer bush shown by FIG. FIG. 9 is a side view of the interling member shown in FIG. 8. XX sectional drawing in FIG. The front view which shows the mounting state to the vehicle of the stabilizer bush while attaching the stabilizer bush shown in FIG. 1 to a stabilizer bar. FIG. 12 is a cross-sectional view taken along the line XII-XII in FIG. 11 and corresponds to FIG. 5.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

  First, the stabilizer bush 10 as one Embodiment of this invention is shown by FIGS. The stabilizer bush 10 is provided to support an anti-vibration support of a middle portion in the longitudinal direction of a stabilizer bar 12 (see FIG. 11) of an automobile on the vehicle body side. In the following description, the axial direction refers to the left-right direction in FIG. 2, and the up-down direction refers to the up-down direction in FIG. 3. However, the vertical direction in the vehicle mounted state is limited by the following description. It is not a thing.

  More specifically, the stabilizer bush 10 of the present embodiment is configured by fixing an interling member 16 to a cylindrical rubber elastic body 14.

  The cylindrical rubber elastic body 14 has a substantially small cross-sectional shape as a whole, and a central hole 18 that extends in a straight line over the entire length in the axial direction with a substantially constant cross section is formed therethrough. As a result, the peripheral wall portion around the center hole 18 in the cylindrical rubber elastic body 14 has an upper wall portion 20 having a semicircular cross section extending substantially half a circumference around the center hole 18 and both circumferential ends of the upper wall portion 20. Side walls 22, 22 extending in the tangential direction from each other, and a lower wall 24 connecting the lower ends of both side walls 22, 22 to each other.

  And the outer peripheral surface of the lower wall part 24 is made into the flat surface which spreads in a substantially rectangular shape as a whole, and it overlaps with the vehicle body of a motor vehicle on this flat surface, and is mounted | worn with it. Further, the outer peripheral surface of the upper wall portion 20 and the side wall portions 22 and 22 is provided with a groove-like recess extending in the circumferential direction, so that gentle irregularities are given in the axial direction. In particular, in the present embodiment, the outer peripheral surfaces of the upper wall portion 20 and the side wall portions 22 and 22 are formed into two concavo-convex shapes that are gently connected in the axial direction.

  Further, at both end portions in the axial direction of the cylindrical rubber elastic body 14, curled portions 26 are formed at a plurality of locations on the circumference. These straight portions 26 are provided at a predetermined distance from each other in the circumferential direction, open to a middle portion in the thickness direction of the peripheral wall portion of the cylindrical rubber elastic body 14, and extend in a predetermined length in the axial direction. Yes. Furthermore, on the outer peripheral surface of the cylindrical rubber elastic body 14, the side wall portions 22, 22 are located in the vicinity of the end portion on the upper wall portion 20 side, and are respectively formed in the hollow recesses 28 opened at the intermediate portion in the axial direction. 28 is formed.

  The spring characteristics of the cylindrical rubber elastic body 14 are adjusted by the plurality of straight portions 26 and the cutout recesses 28. In particular, the straight portion 26 can be used for positioning of the interling member 16 to be described later, and the cutout recess 28 also acts to facilitate a deformation operation when the stabilizer bar 12 is mounted. It has become.

  Further, the lower wall portion 24 is integrally formed with leg portions 30 protruding outward at the four corner portions. These leg portions 30 increase the attachment surface of the lower wall portion 24 to the vehicle body to stabilize the mounting state, and are positioned by engagement with a bracket 48 (see FIGS. 11 and 12) described later. Matching can be done easily.

  A slit-shaped slit 31 that extends linearly over the entire length in the axial direction is formed at one location on the circumference of the cylindrical rubber elastic body 14. The slit 31 is located in the vicinity of one end in the circumferential direction of the upper wall portion 20 and the side wall portion 22 and penetrates from the outer peripheral surface of the cylindrical rubber elastic body 14 to the center hole 18. . The cylindrical rubber elastic body 14 can be elastically deformed so that the upper and lower sides sandwiching the cut 31 are expanded with the opposite side of the cut 31 in the radial direction (left side in FIG. 4) as the hinge center. ing.

  The cylindrical rubber elastic body 14 is made of a general natural rubber (NR), a synthetic rubber material such as butadiene rubber (BR), styrene / butadiene rubber (SBR), or a predetermined lubricant on the rubber material. It is desirable to use so-called self-lubricating rubber or the like that is blended.

  Further, an interling member 16 is disposed in an embedded state in an intermediate portion in the thickness direction of the cylindrical rubber elastic body 14. As shown in FIGS. 8 to 10, the interling member 16 has a configuration in which a pair of intermediate plates 32 a and 32 b are opposed to each other in the radial direction with a predetermined distance therebetween. Since the intermediate plates 32a and 32b of the present embodiment have the same shape, only one intermediate plate 32a will be described.

  The intermediate plate 32a has a curved plate shape that extends in the axial direction with a substantially semicircular cross section that protrudes outward in the circumferential direction of the cylindrical rubber elastic body 14. Then, the central axis of the center hole 18 is disposed substantially as the center of curvature, so that the cylindrical rubber elastic body 14 is embedded in the middle portion in the thickness direction.

  Further, the diameter dimension (circumferential radius of curvature) of the intermediate plate 32a is different in the axial direction, and the axially intermediate part is a large diameter part 34 having a relatively large diameter dimension, while the axially opposite ends. The portions are small diameter portions 36 and 36 having a relatively small diameter.

  In addition, it is preferable that a large-diameter straight portion having a constant diameter dimension and extending straight in the axial direction is provided at a central portion in the axial direction of the large-diameter portion 34, and the large-diameter portion 34 of the present embodiment has a substantially entire length. It is a large diameter straight part. Further, it is preferable that a small-diameter straight portion having a constant diameter dimension and extending straight in the axial direction is provided at the opening-side axial end of the small-diameter portion 36, and the small-diameter portion 36 of the present embodiment has a small diameter over substantially the entire length. It is a straight part.

  Moreover, in this embodiment, the connection part of these large diameter parts 34 and small diameter parts 36 and 36 is made into the taper shape from which a radial dimension changes gradually in an axial direction. That is, the large diameter portion 34 and the small diameter portion 36 are smoothly connected by avoiding the occurrence of a clear step at the connection portion between the large diameter portion 34 and the small diameter portions 36 and 36.

  Here, the length dimension Ls (see FIG. 10) in the axial direction of the small diameter portion 36 is preferably 3 mm or more, and more preferably 5 mm or more. The length dimension Ls of the small-diameter portion 36 is preferably 30% or less, more preferably 20% or less with respect to the intermediate plate 32a, that is, the total length L of the interling member 16 (see FIG. 10). It is said. In addition, since the straight part 26 provided in the cylindrical rubber elastic body 14 is partial on the circumference, and in particular in this embodiment, it is less than a half circumference in total, the straight part is required for the axial length of the small diameter part 36. No special consideration is required.

  When the lid is covered and the length dimension Ls of the small diameter portion 36 is smaller than 3 mm, the stabilizer bar 12 is sufficiently sealed by both end portions in the axial direction of the inner peripheral rubber portion 40 when the stabilizer bush 10 described later is mounted on the vehicle. This is because there is a possibility that the effect of preventing invasion of foreign matter may not be obtained sufficiently. Further, when the length dimension Ls of the small diameter portion 36 is larger than 30% with respect to the total length L of the interling member 16, the tightening force of the small diameter portion 36 against the stabilizer bar 12 becomes excessively large, and the stabilizer bush. The spring characteristic of the cylindrical rubber elastic body 14 becomes hard when a load in a twisting direction or a twisting direction is applied to the tire 10, and the ride comfort of the vehicle may be lowered, and the mounting of the stabilizer bush 10 to the stabilizer bar 12 becomes difficult. Because there is a fear.

  In the interling member 16, if the radius of curvature of the large-diameter portion 34 is R1 (see FIG. 10) and the radius of curvature of the small-diameter portion 36 is R2 (see FIG. 10), the radius of curvature of the large-diameter portion 34 and the small-diameter portion 36 is. Difference: α (see FIG. 10), that is, (R1−R2) is preferably 1 mm ≦ α ≦ 3 mm, and more preferably 1.5 mm ≦ α ≦ 2 mm.

  When α is smaller than 1 mm or larger than 3 mm, the tightening force of the interling member 16 to the stabilizer bar 12 becomes excessively large, and the mounting workability of the stabilizer bush 10 is reduced or required vibration isolation. This is because the characteristics may not be realized or the tightening force by the small-diameter portion 36 is insufficient, and there is a possibility that a foreign matter intrusion preventing effect described later may not be sufficiently exhibited.

  Further, in the present embodiment, through holes 38 are formed in the large diameter portion 34. These through holes 38, 38 are formed by penetrating in the thickness direction of the intermediate plate 32a at a predetermined distance in the circumferential direction, so that the rubber material at the time of molding the cylindrical rubber elastic body 14 can be used. It is easy to wrap around the inner peripheral side and the outer peripheral side of the interling member 16.

  Although the material of the interling member 16 is not particularly limited, the cylindrical rubber elastic body is considered in view of the effect of tightening the stabilizer bar 12 and the reinforcement effect of the cylindrical rubber elastic body 14 described later. It is preferably formed of a metal harder than 14, such as iron, or a synthetic resin such as polypropylene. The intermediate plates 32a and 32b of the present embodiment are made of metal and can be formed by pressing the metal base plate.

  The stabilizer bush 10 of the present embodiment is configured by fixing the interring member 16 having the above-described shape to an intermediate portion in the thickness direction of the cylindrical rubber elastic body 14. In particular, in this embodiment, the cylindrical rubber elastic body 14 is vulcanized and bonded to the inner and outer peripheral surfaces of the intermediate plates 32a and 32b, and the stabilizer bush 10 is formed as an integrally vulcanized molded product. Positioning of the intermediate plates 32a and 32b with respect to the vulcanization mold can be performed by gripping the edge portions of the intermediate plates 32a and 32b exposed to the straight portion 26.

  The cylindrical rubber elastic body 14 is disposed on the inner peripheral rubber portion 40 on the inner peripheral side with respect to the interling member 16 by disposing the interling member 16 at an intermediate portion in the thickness direction of the cylindrical rubber elastic body 14. The outer peripheral rubber part 42 is substantially partitioned from the interling member 16 on the outer peripheral side. The inner peripheral rubber portion 40 and the outer peripheral rubber portion 42 are connected through connecting rubber portions 44 and 44 filled in through holes 38 and 38 provided in the intermediate plates 32a and 32b. 40, the outer peripheral rubber part 42 and the connecting rubber part 44 are integrally formed.

  Here, in the inner peripheral rubber portion 40, the radial dimension (thickness dimension) in the inner peripheral portion of the small diameter portions 36, 36 of the intermediate plates 32a, 32b is D1 (see FIG. 5), and the inner peripheral portion of the large diameter portion 34 Let D2 (see FIG. 5) be the radial dimension (thickness dimension). The radial dimension D2 in the inner peripheral portion of the large-diameter portion 34 is preferably 5 mm ≦ D2 ≦ 10 mm, more preferably 7 mm in consideration of vibration-proof characteristics required for a general stabilizer bush. ≦ D2 ≦ 8 mm.

  Further, both end portions in the circumferential direction of both intermediate plates 32a and 32b are divided portions 46 and 46 facing each other at a predetermined distance in the circumferential direction. In this embodiment, the divided portions 46 of both intermediate plates 32a and 32b. , 46 is provided with a cut 31 in the cylindrical rubber elastic body 14. Thereby, it is avoided that the interling member 16 becomes an obstacle when the stabilizer bush 10 to be described later is attached to the stabilizer bar 12.

  Further, in FIGS. 11 and 12, the stabilizer bar 12 is inserted and attached to the center hole 18 of the stabilizer bush 10 having the above-described shape, and the stabilizer bush 10 is attached to the vehicle body 50 via the bracket 48. The attached state is shown. In the present invention, the bracket is not limited in any way, but the bracket 48 of the present embodiment includes a mounting portion 52 made of a band plate metal fitting formed in a shape along the outer peripheral surface shape of the stabilizer bush 10, and a mounting. There are provided mounting legs 54, 54 made of a pair of flat metal fittings extending outward from the portion 52.

  That is, the bracket 48 has a pair of flat mounting legs 54, 54 extending outward from both end edges on the opening side of the substantially U-shaped groove-shaped mounting portion 52, so that the Ω shape is formed as a whole. It has a cross-sectional shape. The mounting portion 52 has a corrugated shape corresponding to the outer peripheral surface of the upper wall portion 20 and the side wall portions 22 and 22 of the cylindrical rubber elastic body 14 so as to position the cylindrical rubber elastic body 14 in the axial direction. It has become. Furthermore, the mounting leg portions 54, 54 are formed with respective recesses 58 that engage with the respective leg portions 30 protruding from the lower wall portion 24 of the cylindrical rubber elastic body 14, and the bolt holes 60, 60 is formed penetrating.

  Thus, when the stabilizer bush 10 of the present embodiment is mounted on the stabilizer bar 12, the both sides in the circumferential direction sandwiching the cut 31 are expanded and deformed, so that the stabilizer bar 12 is extrapolated from the side. Thus, the stabilizer bar 12 can be inserted into the center hole 18 of the stabilizer bush 10.

  After the stabilizer bush 10 is mounted, the upper and lower sides sandwiching the cut 31 are automatically returned to a position where they are in contact with each other by the elastic restoring action of the cylindrical rubber elastic body 14. Even if it does not return to the position where the upper and lower sides sandwiching the cut 31 in the cylindrical rubber elastic body 14 come into contact with each other, the cylindrical rubber is tightened by the tightening force of the bolts 62 and 62 that fix the bracket 48 to the vehicle body 50. The elastic body 14 is compressed in the circumferential direction, and the upper and lower sides sandwiching the cut 31 are brought into contact with each other.

  Thereby, the stabilizer bush 10 can be attached to the stabilizer bar 12 in a non-adhesive manner. Moreover, the outer peripheral surface of the stabilizer bush 10 is attached and attached to the vehicle body side in a non-adhesive manner by a bracket 48 assembled in a positioning state in the axial direction and the circumferential direction. As a result, the stabilizer bar 12 is supported by the vehicle body 50 in a vibration-proof manner via the stabilizer bush 10 and the bracket 48.

  Here, in the vehicle mounting state of the stabilizer bush 10 shown in FIGS. 11 and 12, the outer diameter dimension of the stabilizer bar 12: φ2 is the inner diameter dimension of the center hole 18 of the cylindrical rubber elastic body 14 in the free state before mounting. Is larger than φ1 (φ1 <φ2), and the bracket 48 is bolted to the vehicle body 50, so that the inner peripheral rubber portion 40 positioned between the stabilizer bar 12 and the interring member 16 is radially Pre-compressed. That is, in the inner peripheral rubber portion 40 in the vehicle mounted state, if the radial dimension at the inner peripheral portion of the small diameter portions 36, 36 of the intermediate plates 32a, 32b is d1 (see FIG. 12), d1 <D1. Yes. Further, when the radial dimension in the inner peripheral portion of the large diameter portion 34 of the intermediate plates 32a and 32b is d2 (see FIG. 12), d2 <D2.

  Accordingly, in the inner peripheral rubber portion 40, the radial compression rate in the inner peripheral portion of the small diameter portion 36 is represented by (D1-d1) / D1, while the radial compression rate in the inner peripheral portion of the large diameter portion 34 is It is indicated by (D2-d2) / D2. Since the radial displacement amount of the interling member 16 in the small diameter portion 36 and the large diameter portion 34 is equal, (D1-d1) and (D2-d2) are equal. Since D <b> 1 <D <b> 2, the radial compression ratio in the inner peripheral rubber portion 40 is larger in the inner peripheral portion of the small diameter portion 36 than in the inner peripheral portion of the large diameter portion 34. That is, in the state where the stabilizer bush 10 is mounted on the vehicle, in the inner peripheral rubber portion 40, the radial compression rate at both axial ends is larger than the radial compression rate at the axial middle portion.

  In the stabilizer bush 10 of the present embodiment configured as described above, the inner rubber portion 40 is provided on the stabilizer bar 12 by providing the interring member 16 at the intermediate portion in the thickness direction of the cylindrical rubber elastic body 14. A clamping force is exerted by the interling member 16 through the via. And the small diameter parts 36 and 36 are provided in the axial direction both ends of the interling member 16, and the radial compression rate is increased in the axial both ends of the inner peripheral rubber part 40, whereby the inner peripheral rubber part 40 and the stabilizer are increased. The space between the bars 12 is sealed with a sufficient tightening force at both axial end portions. Thereby, it is effectively avoided that a gap or an opening is generated between the inner peripheral rubber portion 40 and the stabilizer bar 12, and muddy water, gravel, or the like invades or generation of abnormal noise accompanying it effectively. Can be prevented.

  Further, since the radial compressibility of the intermediate portion in the axial direction in the inner peripheral rubber portion 40 is made smaller than that in both end portions in the axial direction, a load in the twisting direction and the twisting direction is input to the stabilizer bush 10. In particular, the spring characteristics of the cylindrical rubber elastic body 14 can be prevented from becoming excessively hard, and a good riding comfort of the vehicle can be ensured. Furthermore, the spring characteristics of the cylindrical rubber elastic body 14 can be set as appropriate depending on, for example, the axial dimensions of the large diameter portion 34 and the small diameter portion 36, or the radial dimension difference α thereof, and the stabilizer bush 10 has excellent design freedom. Have a degree.

  In particular, in the present embodiment, the inner diameter dimension φ1 of the center hole 18 of the cylindrical rubber elastic body 14 is substantially constant over the entire length in the axial direction, and the inner peripheral surface of the center hole 18 is provided with irregularities. Thus, the local concentration of stress and strain accompanying the above can be effectively avoided, and the durability of the stabilizer bush 10 can be improved. Further, the cylindrical rubber elastic body 14 can be easily molded, and the stabilizer bush 10 can be easily manufactured, and the stabilizer bush 10 can be easily attached to the stabilizer bar 12.

  In the present embodiment, the large-diameter portion 34 has a straight shape over substantially the entire length in the axial direction, and the small-diameter portions 36 and 36 also have a straight shape over almost the entire length in the axial direction. When the rubber elastic body 14 is compressed, local stress concentration and distortion in the inner peripheral rubber portion 40 can be effectively avoided.

  As mentioned above, although embodiment of this invention was explained in full detail, this invention is not limited by the specific description. For example, in the above-described embodiment, the interling member 16 is configured by the intermediate plates 32a and 32b having a substantially semicircular arc shape, but is not limited to such an aspect. That is, the interling member has a C-shape as described in Patent Documents 1 and 2 and Japanese Patent Application Laid-Open No. 2013-56616, and a shape that is divided into three or more in the circumferential direction as described in Japanese Patent Application Laid-Open No. 2012-240592. May be. In any of these cases, the stabilizer bush 12 can be expanded and mounted on the stabilizer bar 12 by forming a cut portion of the cylindrical rubber elastic body between the divided portions of the interling member. . However, the means for attaching the stabilizer bush to the stabilizer bar 12 is not limited to such means.

  Moreover, in the said embodiment, while the large diameter part 34 was made into the straight shape over the axial direction substantially full length, and the small diameter parts 36 and 36 were also made into the straight shape over the axial direction substantially full length, in this aspect, For example, a straight portion of the interling member may not be provided, and the diameter may be changed over substantially the entire length in the axial direction.

  That is, for example, the large-diameter portion may have a spherical shape and the interling member may have a bulge shape, or the inner peripheral surface of the large-diameter portion may be uneven. In addition, it is also possible to adjust the spring characteristics of the cylindrical rubber elastic body by providing irregularities on the inner peripheral surface of the large diameter portion. In such a case, since the small diameter portions are provided at both axial ends of the interling member, the effect of preventing foreign matter from entering between the stabilizer bar 12 and the cylindrical rubber elastic body is exhibited. Even if a gap is generated between the peripheral surface and the stabilizer bar 12, it is possible to effectively avoid foreign matter from entering the gap and to improve the degree of freedom in tuning the spring characteristics.

  Furthermore, in the above-described embodiment, the inner diameter dimension φ1 of the center hole 18 in the cylindrical rubber elastic body 14 is substantially constant over the entire length in the axial direction. The inner diameter dimension of both axial end portions of the inner diameter portion may be smaller than that of the intermediate portion in the axial direction, and the inner peripheral surface of the inner peripheral rubber portion in the inner peripheral portion of the smaller diameter portion projects into, for example, the center hole. You may provide an annular protrusion integrally with a cylindrical rubber elastic body. As a result, the radial compression rate at both axial end portions of the inner peripheral rubber portion can be supplementarily increased, so that the sealing effect by the cylindrical rubber elastic body is improved locally and foreign matter can be further penetrated. Can be prevented.

  Furthermore, in the above-described embodiment, in consideration of workability at the time of forming an integrally vulcanized molded product of the cylindrical rubber elastic body 14 and the interling member 16, the cylindrical rubber elastic body 14 is excellent at both axial end surfaces. The end portions 26 are provided, and both end portions in the axial direction of the interling member 16 are exposed in the curled portion 26. For example, the end portions in the axial direction of the cylindrical rubber elastic body are flat surfaces because no curled portion is formed. Then, both axial ends of the interling member may protrude from the flat surface.

  In addition, although the connection part of the large diameter part 34 and the small diameter parts 36 and 36 in the intermediate | middle board 32a, 32b may have the level | step difference which spreads in the direction orthogonal to an axis | shaft, it is made into the taper shape like the said embodiment, and connects smoothly. It is preferred that As a result, the interling member can have a substantially constant thickness dimension over substantially the entire length in the axial direction, and a partial reduction in strength can be avoided.

  Moreover, in the said embodiment, although the upper wall part 20 of the cylindrical rubber elastic body 14 was made into two mountain shape, the shape of an upper wall part respond | corresponds to the shape of the bracket attached to outer periphery, It is not limited.

10: Stabilizer bush, 12: Stabilizer bar, 14: Cylindrical rubber elastic body, 16: Interling member, 18: Center hole, 34: Large diameter part (large diameter straight part), 36: Small diameter part (small diameter straight part) , 40: inner peripheral rubber part, 42: outer peripheral rubber part

Claims (5)

A cylindrical rubber elastic body having a central hole through which the stabilizer bar is inserted, and an inner peripheral rubber portion and an outer peripheral rubber portion fixed to the intermediate portion in the thickness direction of the cylindrical rubber elastic body. In a stabilizer bush configured to include an interling member arranged to partition the
Small diameter portions are provided on both sides in the axial direction of the large diameter portion provided in the intermediate portion in the axial direction with the diameter dimension of the interling member being different in the axial direction, and the radial thickness dimension of the inner peripheral rubber portion is Since the inner peripheral portion of the small diameter portion is smaller than the inner peripheral portion of the large diameter portion, the radial compression rate in the inner peripheral rubber portion in the attached state to the stabilizer bar is axially intermediate. The stabilizer bush characterized by being enlarged in the axial direction both ends compared with the part. 2. The stabilizer bush according to claim 1 , wherein an inner diameter dimension of the center hole has a substantially constant cross-sectional shape over an entire length in an axial direction in a free state before being attached to the stabilizer bar . In the free state before mounting to the stabilizer bar, the interling member is provided with a large-diameter straight portion extending at a constant diameter at a central portion of the large-diameter portion, and an opening side shaft of the small-diameter portion. The stabilizer bush of Claim 1 or 2 with which the small diameter straight part extended by a fixed diameter dimension is provided in the direction edge part. In the free state before mounting to the stabilizer bar, the axial length of the small diameter portion in the interling member is 3 mm or more and 30% or less of the total axial length of the interling member. The stabilizer bush of any one of Claims 1-3. The radial dimension difference between the large diameter portion and the small diameter portion is set within a range of 1 to 3 mm in the interling member in a free state before being mounted on the stabilizer bar. The stabilizer bush of Claim 1.

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