JP2016196921A - Vehicle thrust bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle thrust bearing including a seal member which reduces the weight, provides rigidity, enables easy assembly, and secures the sealability without using an annular core grid.SOLUTION: In a vehicle thrust bearing 100, an annular seal elastic member 140 is installed between a lower case 120 and an upper case 110 and seals an installation portion from a case outer periphery side or a case inner periphery side. The annular seal elastic member 140 includes: an annular inner periphery side base part 141 installed at one of the upper case 110 and the lower case 120; and annular lip parts 142A to 142D which extend from the annular inner periphery side base part 141 to the case outer periphery side and contact with the other of the upper case 110 and the lower case 120.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a thrust bearing for a vehicle having an upper case and a lower case and relatively rotating, and in particular, a thrust bearing for a strut suspension (McPherson type) and a thrust bearing for an air suspension in a four-wheeled vehicle. The present invention relates to a thrust bearing for a vehicle incorporated in a vehicle.

  Conventionally, as a thrust bearing for a vehicle, an upper case made of a synthetic resin in which an annular lower surface is formed in the axial direction of a piston rod used for a strut type suspension in a front wheel of a four-wheeled vehicle, and a shaft center around the upper case The lower case made of synthetic resin, which is overlapped in a rotatable manner and has an annular upper surface, and the upper case is disposed between the annular lower surface of the upper case and the annular upper surface of the lower case. In order to seal the gap between the lower case and the upper case, and the sliding bearing piece made of synthetic resin that contacts the lower surface of the lower case with the lower surface of the lower case and the lower surface of the upper case. There is known a sliding bearing provided with an annular elastic seal member disposed on the outer periphery of the lower case and fixed so as to cover an annular cored bar having an L-shaped cross section (for example, , Patent Document 1).

JP 2012-097904 A (refer to FIG. 2, FIG. 5, FIG. 6 in particular)

  However, since the conventional sliding bearing described above has a structure in which the sealing member has an annular cored bar, there is a problem that the weight is heavy, or the rigidity is insufficient if only an elastic sealing member such as rubber is used without an annular cored bar. As a result, the assembly becomes difficult and the sealing performance may be insufficient.

  Therefore, the present invention solves the problems of the prior art as described above, that is, the object of the present invention is to reduce the weight and provide rigidity without an annular cored bar and facilitate assembly. It is another object of the present invention to provide a vehicle thrust bearing having a seal member that ensures sealing performance.

  The invention according to claim 1 includes an annular upper case that comes into contact with the vehicle body side mounting portion, and an annular lower case that overlaps with the upper case so as to be rotatable relative to each other, and the upper case and the lower case, In a thrust bearing for a vehicle that supports a thrust load at a contact location where direct contact or indirect contact is made, it is installed between the upper case and the lower case, and the contact location is located on the case outer peripheral side or the case inner peripheral side. An annular seal elastic member to be sealed includes an annular inner peripheral base installed in one of the upper case and the lower case, and the other of the upper case and the lower case extending from the annular inner peripheral base to the case outer peripheral side. The above-described problems are solved by providing a plurality of annular lip portions that come into contact with each other.

  In the invention according to claim 2, in addition to the configuration of the vehicle thrust bearing described in claim 1, a synthetic resin sliding bearing piece for supporting the thrust load is provided between the upper case and the lower case. The above-described problems are further solved by being installed in the annular space formed in the above.

According to a third aspect of the present invention, in addition to the configuration of the vehicle thrust bearing according to the first or second aspect, the annular seal elastic member has the plurality of lip portions before elastic deformation of the other lip portion. By having the overlap part which contacts the case and elastically deforms, the above-described problems are further solved.
Here, the “overlap portion” refers to a portion where the shape before elastic deformation of the plurality of annular lip portions overlaps with the other case.

  According to a fourth aspect of the present invention, in addition to the configuration of the vehicle thrust bearing according to the third aspect, the overlap portion is arranged along the clearance path between the upper case and the lower case. By gradually increasing the size toward the side, the above-described problems are further solved.

  According to the fifth aspect of the present invention, in addition to the configuration of the vehicle thrust bearing according to the third aspect, the overlap portion is arranged along the clearance path between the upper case and the lower case. The above-described problems are further solved by providing the small size sequentially toward the side.

  The invention according to claim 6 is formed on the seal inner peripheral side of the annular inner peripheral base in addition to the configuration of the vehicle thrust bearing according to any one of the first to fifth aspects. The annular ridge is in elastic contact with the upper case or the lower case, thereby further solving the above-described problems.

  According to a seventh aspect of the present invention, in addition to the configuration of the vehicle thrust bearing according to any one of the first to sixth aspects, the lower case is a piston used for a shock absorber of a vehicle suspension. The above-described problem is further solved by overlapping the upper case around the axis of the rod so as to be relatively rotatable and supporting a load from a damper coil spring of the suspension.

  The thrust bearing for a vehicle according to the present invention includes an annular upper case that abuts on the vehicle body side mounting portion and an annular lower case that overlaps with the upper case so as to be rotatable relative to the upper case. Not only can smooth relative rotation with the case be realized, but also the following specific effects can be achieved.

According to the vehicle thrust bearing of the first aspect of the present invention, the annular seal elastic member that is installed between the upper case and the lower case and seals the contact portion on the case outer peripheral side or the case inner peripheral side is An annular inner peripheral base portion installed on one of the case and the lower case, and a plurality of annular lip portions extending from the annular inner peripheral base portion to the case outer peripheral side and coming into contact with the other of the upper case and the lower case As a result, the rigidity of the annular seal elastic member itself is increased as compared with the rubber having the conventional structure.
Furthermore, since the momentum of the muddy water or the like to enter through the multi-stage seal structure is reduced at a stroke or in steps, sufficient sealing performance can be ensured.
Further, for example, even when an eccentric load is generated in the circumferential direction by the coil spring of the suspension, at least a part of the plurality of annular lip portions of the annular seal elastic member on both the side where the load acts largely and the side where the load acts little Is in contact with the other of the upper case and the lower case without any gaps, so that a sufficient sealing performance can be ensured even when an unbalanced load occurs.

  According to the vehicle thrust bearing of the invention of claim 2, in addition to the effect of the invention of claim 1, a synthetic resin sliding bearing piece for supporting the thrust load is provided between the upper case and the lower case. Since the frictional resistance between the upper case and the lower case is reduced by being installed in the annular space formed between them, the relative rotation between the upper case and the lower case is made smoother. Can do.

  According to the vehicle thrust bearing of the invention of claim 3, in addition to the effect of the invention of claim 1 or claim 2, the annular seal elastic member has a plurality of lip portions before elastic deformation of the other lip portion. Since it has a more reliable multi-stage seal structure by having the overlap part which contacts the case and elastically deforms, it is possible to reduce the momentum of muddy water or the like to enter at once or in stages.

  According to the vehicle thrust bearing of the invention of claim 4, in addition to the effect of the invention of claim 3, the overlap portion is a contact point along the clearance path between the upper case and the lower case. Because the sealing performance increases step by step toward the contact location side in the multi-stage seal structure by being sequentially provided large toward the side, even when muddy water passes through the first seal, Intrusion of muddy water and the like can be reliably prevented with the second and subsequent seals.

  According to the vehicle thrust bearing of the invention of claim 5, in addition to the effect of the invention of claim 3, the overlap portion is a contact location along the clearance path between the upper case and the lower case. Since the sealing performance of the inlet side seal is the highest in the multi-stage seal structure, the first seal surely weakens the momentum such as muddy water. Even when muddy water or the like passes through the seal, intrusion of muddy water or the like that has lost its momentum can be reliably prevented by the second and subsequent seals.

  According to the thrust bearing for vehicles of the invention concerning Claim 6, in addition to the effect which the invention concerning any one of Claims 1 thru / or 5 shows, it forms in the seal inner circumference side of a ring inner circumference side base. Since the annular ridge is elastically in contact with the upper case or the lower case, the annular ridge serves as a tightening allowance, so that it can be sealed without any gap between the annular inner peripheral base and one side. it can.

  According to the vehicle thrust bearing of the invention of claim 7, in addition to the effect of the invention of any one of claims 1 to 6, the lower case is used for a shock absorber of a vehicle suspension. By overlapping the upper case around the axis of the piston rod, which is relatively rotatable, and supporting the load from the damper coil spring of the suspension, the annular seal elastic member can be connected to the upper case and the lower case in response to the eccentric load. Therefore, even if the lower case is slightly inclined with respect to the upper case due to an offset load applied to the lower case, the lower case can be reliably sealed.

1 is a partially sectional perspective view of a thrust sliding bearing for a vehicle that is a first embodiment of the present invention. 1 is an exploded perspective view of a thrust sliding bearing for a vehicle that is a first embodiment of the present invention. The top view seen from the code | symbol 3 shown in FIG. Sectional drawing seen by the code | symbol 4-4 shown in FIG. The expanded sectional view of the location shown with the code | symbol 5 shown in FIG. (A) (B) is sectional drawing of an unbalanced load state. (A) is a principal part expanded sectional view of the thrust sliding bearing for vehicles which is 2nd Example of this invention, (B) is a principal part expanded sectional view of the thrust sliding bearing for vehicles which is 3rd Example of this invention. The principal part expanded sectional view of the thrust sliding bearing for vehicles which is 4th Example of this invention. The expanded sectional view of the thrust sliding bearing for vehicles which is the 5th example of the present invention. The expanded sectional view of the thrust sliding bearing for vehicles which is the 6th example of the present invention.

  The present invention includes an annular upper case that comes into contact with the vehicle body-side mounting portion, and an annular lower case that overlaps with the upper case so that the upper case and the lower case are directly or indirectly connected. In a thrust bearing for a vehicle that supports a thrust load at a contact point that contacts, an annular seal elastic member that is installed between the upper case and the lower case and seals the contact point on the case outer peripheral side or the case inner peripheral side is An annular inner peripheral base portion installed on one of the case and the lower case, and a plurality of annular lip portions extending from the annular inner peripheral base portion to the case outer peripheral side and coming into contact with the other of the upper case and the lower case Therefore, any specific embodiment can be used as long as it can be assembled without an annular cored bar and can secure sufficient sealing performance even when an uneven load occurs. But it may be in.

For example, a vehicle thrust bearing may be provided with a bearing piece that supports a thrust load by being interposed in an annular space formed between an upper case and a lower case, or may be provided with an upper case without a bearing piece. The lower case may slide directly.
Further, when a bearing piece is provided, the bearing piece may be a sliding bearing piece that slides with respect to the upper case or the lower case, or may be a rolling bearing piece that holds a rolling element such as a ball so as to roll freely.

The vehicle suspension may be of any structure as long as a thrust load is applied.
The upper case only needs to be in contact with the vehicle body side mounting portion, and the strut type suspension as an example of the suspension is a type in which the upper end portion of the shock absorber piston rod is fitted to the vehicle body side mounting portion. It may be any of the types fitted to the upper case.
The elastic material may be any material that can be elastically deformed, and may be any material such as rubber such as natural rubber or synthetic rubber, or resin such as elastomer or polyethylene.

A vehicle thrust sliding bearing 100 according to a first embodiment of the present invention will be described below with reference to FIGS.
Here, FIG. 1 is a partially sectional perspective view of a vehicular thrust slide bearing 100 according to a first embodiment of the present invention, and FIG. 2 is a vehicular thrust slide bearing 100 according to a first embodiment of the present invention. 3 is a plan view seen from the reference numeral 3 shown in FIG. 1, FIG. 4 is a cross-sectional view taken from the reference numeral 4-4 shown in FIG. 3, and FIG. 6 (A) and 6 (B) are cross-sectional views in an unbalanced load state, and FIG. 6 (A) is loaded more than FIG. 6 (B). It is sectional drawing of the state which is acting large.

As shown in FIGS. 1 to 6, a vehicle thrust sliding bearing 100 as a vehicle thrust bearing according to a first embodiment of the present invention includes an annular upper case 110 made of a synthetic resin and an annular case made of a synthetic resin. A lower case 120 and an annular sliding bearing piece 130 made of synthetic resin as a bearing piece are provided.
Among these, the upper case 110 is configured to come into contact with a vehicle-side attachment member VA as a vehicle body-side attachment portion.

  In the present embodiment, the upper case 110 includes an annular upper case base 111 attached to the vehicle side by forming an annular upper case upper surface 111a and an upper case lower surface 111b in the axial direction Y of the piston rod, and the upper case. The inner peripheral side cylindrical portion 112 hanging from the inner peripheral end in the radial direction X of the base 111 and the outer peripheral side cylindrical portion 113 hanging from the outer peripheral end in the radial direction X of the upper case base 111 are integrally provided. .

In addition, the lower case 120 is configured to overlap with the upper case 110 so as to be rotatable around the axis AX of the piston rod.
In the present embodiment, the lower case 120 includes an annular lower case base 121 that is superposed on the upper case 110 so as to be rotatable about the axis AX with respect to the upper case 110, and a radially inner side of the lower case base 121. Each has an inner peripheral cylindrical portion 122 that hangs down.

A base outer peripheral surface 121a is formed on the outer side in the radial direction of the lower case base 121. The outer annular groove 121aa formed in the base outer peripheral surface 121a is formed only of synthetic rubber, which is an example of an elastic material described in detail later. An annular seal elastic member 140 is installed.
An outer annular claw 113 a is formed on the outer cylindrical portion 113 of the upper case 110.
Then, when the outer annular claw 113a abuts on the annular seal elastic member 140, the relative movement between the upper case 110 and the lower case 120 in the axial direction Y is restricted.
That is, it is possible to prevent the upper case 110 and the lower case 120 from being separated from each other.

Further, an annular flange 121b is formed on the outer side in the radial direction from the base outer peripheral surface 121a, and the annular flange 121b is configured so that the inlet EN of the clearance path RO between the upper case 110 and the lower case 120 faces sideways. Has been.
This makes it difficult for muddy water or the like generated from the lower side to the upper side to enter the gap route RO between the upper case 110 and the lower case 120.

  Further, an inner annular ridge 122 a is formed inside the inner peripheral cylindrical portion 122 of the lower case 120, and an inner annular ridge 122 a is formed at the lower end of the inner peripheral cylindrical portion 112 of the upper case 110. It is installed so as to mesh with the annular groove 112a with a slight gap.

The annular slide bearing piece 130 is configured to support a thrust load and a radial load that are loaded in an annular space formed between the upper case 110 and the lower case 120.
In the present embodiment, the annular sliding bearing piece 130 includes an annular space between the upper case lower surface 111 b of the upper case base 111 and the lower case upper surface 121 c of the lower case base 121 and the outer peripheral surface 112 b and the lower portion of the inner peripheral cylindrical portion 112. It is installed in an annular space between the inner peripheral surface 121 d of the case base 121.

The annular sliding bearing piece 130 includes an annular thrust sliding bearing piece portion 131, a cylindrical radial sliding bearing piece portion 132, and a bearing piece side rotation stop recessed portion 133 protruding downward from the thrust sliding bearing piece portion 131. have.
The thrust slide bearing piece 131 includes a bearing upper surface 131a that slidably contacts the upper case lower surface 111b of the upper case base 111, and a bearing lower surface 131b that contacts the lower case upper surface 121c of the lower case base 121 of the lower case 120. Have.

On the other hand, the radial sliding bearing piece 132 includes a bearing inner peripheral surface 132a that slidably contacts the outer peripheral surface 112b of the inner peripheral cylindrical portion 112 of the upper case 110, and an inner peripheral surface of the lower case base 121 of the lower case 120. It has a bearing outer peripheral surface 132b in contact with 121d.
Further, the bearing piece side rotation stopping recess 133 engages with a bearing piece rotation stopping projection 123 formed on the inner peripheral surface 121 d of the lower case base 121, and restricts the rotation of the annular sliding bearing piece 130 relative to the lower case 120. .

  In the present embodiment, as an example, the bearing piece side rotation stopping concave portion 133 and the bearing piece rotation stopping convex portion 123 are provided so that the annular sliding bearing piece 130 does not rotate with respect to the lower case 120, but these are not provided. In addition, the annular slide bearing piece 130 may be configured to rotate with respect to the lower case 120.

As shown in FIGS. 4 and 5, a spring pad SP formed in an annular shape with rubber is installed on the lower case lower surface 121 e of the lower case base 121.
In the strut type suspension (McPherson type), the vehicle thrust sliding bearing 100 abuts the upper case upper surface 111a of the upper case 110 against the vehicle side seating surface VA1 of the vehicle side mounting member VA as the body side mounting portion. The spring pad SP is brought into contact with the upper end portion of the damper coil spring SS, and the vehicle thrust slide bearing 100 is installed between the vehicle side seating surface VA1 of the vehicle side mounting member VA and the damper coil spring SS, Incorporated.
The spring pad SP may be formed integrally with the lower case 120.

In this embodiment, the annular seal elastic member 140 is formed only of an elastic material, and is between the inner peripheral surface 113b of the outer peripheral side cylindrical portion 113 of the upper case 110 and the base outer peripheral surface 121a of the lower case base 121 of the lower case 120. Is installed.
Then, the contact location between the annular sliding bearing piece 130 and the upper case 110 and the contact location between the annular slide bearing piece 130 and the lower case 120, which are contact locations, are sealed on the case outer peripheral side as an example of the case outer peripheral side or the case inner peripheral side. It is configured to stop.

Further, the annular seal elastic member 140 includes an annular inner peripheral base 141 installed in the outer annular groove 121aa of the base outer peripheral surface 121a of the lower case base 121 which is one of the upper case 110 and the lower case 120, and an annular inner peripheral side. A first-stage annular lip portion 142 </ b> A that is a plurality of annular lip portions 142 that extend from the base portion 141 toward the outer peripheral side and abut against the inner peripheral surface 113 b of the outer cylindrical portion 113 of the upper case 110 that is the other of the upper case 110 and the lower case 120. To fourth-stage annular lip 142D.
The first-stage annular lip 142A to the fourth-stage annular lip 142D seal the gap path RO between the upper case 110 and the lower case 120.

Thereby, the rigidity of the annular seal elastic member 140 itself is increased as compared with the rubber having the conventional structure.
That is, it is assembled without an annular cored bar.
Furthermore, it becomes a multi-stage seal structure, and the momentum such as muddy water to invade is reduced at once or in steps.
That is, sufficient sealing performance is ensured.

  Further, as shown in FIGS. 6A and 6B, for example, even when an unbalanced load is generated in the circumferential direction R by the damper coil spring SS of the suspension, the load acts largely and acts small. On both sides, at least a part of the plurality of annular lip portions 142 of the annular seal elastic member 140 contacts the inner peripheral surface 113b of the outer peripheral side cylindrical portion 113 of the upper case 110 without a gap.

In this embodiment, the shape of the first-stage annular lip portion 142A to the fourth-stage annular lip portion 142D before elastic deformation (the shape indicated by the one-dot chain line in FIG. 5) and the shape of the outer peripheral side cylindrical portion 113 of the upper case 110 are used. The overlap portions OL1 to OL4 that overlap with the upper case 110 are sequentially provided from the inlet EN toward the annular slide bearing piece 130 along the clearance path RO between the upper case 110 and the lower case 120.
In other words, in the elastic deformation region of the first-stage annular lip portion 142A to the fourth-stage annular lip portion 142D arranged along the clearance path RO between the upper case 110 and the lower case 120 and abutting and interfering with the upper case 110. Certain overlap portions OL1 to OL4 are sequentially provided larger toward the annular sliding bearing piece 130 side.

Thereby, in a multistage seal structure, the sealing performance increases stepwise toward the annular slide bearing piece 130 side.
That is, even when muddy water passes through the first seal by the first-stage annular lip 142A, the second and subsequent seals by the second-stage annular lip 142B to the fourth-stage annular lip 142D are surely secured. Muddy water can be stopped.

Furthermore, in this embodiment, as shown in FIG. 2, an annular ridge 141 a is formed on the seal inner peripheral side of the annular inner peripheral base 141.
As shown in FIG. 5, the annular protrusion 141 a is in elastic contact with the outer annular groove 121 aa of the lower case 120.
In other words, the outer annular concave groove 121aa overlaps with the shape before elastic deformation.
Thereby, the annular protrusion 141a becomes a fastening allowance.
That is, the space between the annular inner peripheral base 141 and the lower case base 121 is sealed without a gap.

  A vehicle thrust slide bearing 100 as a vehicle thrust bearing according to the first embodiment of the present invention thus obtained is installed between the upper case 110 and the lower case 120 and the annular slide bearing piece 130 is provided. An annular seal elastic member 140 that seals the contact location on the outer periphery side of the case has an annular inner peripheral side base 141 installed on the lower case base 121 of the lower case 120 that is one of the upper case 110 and the lower case 120, A first-stage ring as a plurality of annular lip portions 142 extending from the peripheral base portion 141 toward the outer peripheral side of the case and contacting the inner peripheral surface 113b of the outer peripheral cylindrical portion 113 of the upper case 110 which is the other of the upper case 110 and the lower case 120 By including the lip part 142A to the fourth-stage annular lip part 142D, it can be assembled without an annular cored bar, Even when an Flip it is possible to secure a sufficient sealability.

  Further, the shape of the first-stage annular lip portion 142A to the fourth-stage annular lip portion 142D before the elastic deformation (the shape indicated by the one-dot chain line in FIG. 5) and the shape of the outer peripheral side cylindrical portion 113 of the upper case 110 are exceeded. The overlap portions OL1 to OL4 to be wrapped are provided one by one in order from the inlet EN toward the annular slide bearing piece 130 along the clearance path RO between the upper case 110 and the lower case 120. Even when muddy water or the like passes through the first-stage annular lip 142A that is the seal of the eyes, the muddy water is surely secured by the second-stage annular lip 142B to the fourth-stage annular lip 142D that are the second and subsequent seals. Intrusion such as can be prevented.

  Furthermore, the annular protrusion 141a formed on the seal inner peripheral side of the annular inner peripheral base 141 is in elastic contact with the lower case base 121 of the lower case 120, which is one of the annular inner peripheral bases. 141 and the lower case base 121 of the lower case 120 can be sealed without a gap, and the effect is enormous.

Next, a vehicle thrust sliding bearing 200 according to a second embodiment of the present invention will be described with reference to FIG.
Here, FIG. 7A is an enlarged cross-sectional view of a main part of a vehicle thrust slide bearing 200 according to a second embodiment of the present invention.
The vehicular thrust slide bearing 200 according to the second embodiment is obtained by changing the cross-sectional shape of the annular seal elastic member 140 of the vehicular thrust slide bearing 100 according to the first embodiment when viewed from the circumferential direction R. Is the same as the thrust sliding bearing for a vehicle 100 of the first embodiment, detailed description of common items is omitted, and only the reference numerals of the 200 series in which the lower two digits are common are attached.

As shown in FIG. 7A, the thrust sliding bearing 200 for a vehicle that is the second embodiment of the present invention is provided with a first-stage annular lip portion 242A and a second-stage annular lip portion 242B as the annular lip portion 242. ing.
Here, the annular lip portion 242 does not necessarily extend only in the radial direction X orthogonal to the axial direction Y.

In the present embodiment, the first-stage annular lip portion 242A and the second-stage annular lip portion 242B before elastic deformation are formed to be inclined downward in the axial direction from the radially inner side to the outer side.
Accordingly, when the upper case 210 and the lower case 220 are relatively assembled, the outer peripheral side cylindrical portion 213 of the upper case 210 abuts on the second-stage annular lip portion 242B and the second-stage annular lip portion 242B is inclined. Guided.
That is, the relative assembly of the upper case 210 and the lower case 220 is facilitated.

Next, a vehicle thrust sliding bearing 300 according to a third embodiment of the present invention will be described with reference to FIG.
Here, FIG. 7B is an enlarged cross-sectional view of a main part of a vehicle thrust slide bearing 300 according to a third embodiment of the present invention.
The thrust thrust bearing 300 for a vehicle according to the third embodiment is obtained by changing the cross-sectional shape of the annular seal elastic member 140 of the thrust thrust bearing 100 for a vehicle according to the first embodiment when viewed from the circumferential direction R. Is the same as the thrust sliding bearing for a vehicle 100 of the first embodiment, detailed description of the common matters is omitted, and only the reference numbers in the 300 series are shared by the lower two digits.

In the thrust sliding bearing 300 for a vehicle that is the third embodiment of the present invention, as shown in FIG. 7B, the shapes of the first-stage annular lip portion 342A to the fourth-stage annular lip portion 342D before elastic deformation (FIG. 7). (B), the overlapping portions OL1 to OL4 that overlap the shape of the outer cylindrical portion 313 of the upper case 310 are gap paths RO between the upper case 310 and the lower case 320. Are sequentially provided from the inlet EN toward the annular sliding bearing one side.
In other words, a first-stage annular lip portion as a plurality of annular lip portions 342 disposed along the clearance path RO between the upper case 310 and the lower case 320 and abutting and interfering with the outer peripheral side cylindrical portion 313 of the upper case 310. Overlapping portions OL1 to OL4, which are elastic deformation regions of 342A to the fourth-stage annular lip portion 342D, are sequentially provided smaller toward the annular sliding bearing piece side.

Thereby, the sealing performance of the seal on the inlet EN side becomes the highest in the multi-stage seal structure.
In other words, even if the first seal by the first-stage annular lip 342A weakens the momentum of the muddy water and the muddy water passes through the first seal, the muddy water that has lost its momentum is in two stages. The second and subsequent seals by the second annular lip 342D to the fourth annular lip 342D are securely stopped.

  The thrust sliding bearing 300 for a vehicle according to the third embodiment of the present invention thus obtained has a shape before elastic deformation of the first-stage annular lip portion 342A to the fourth-stage annular lip portion 342D (FIG. 7B). The overlapping portions OL1 to OL4 that overlap with the shape of the outer cylindrical portion 313 of the upper case 310 are along the gap path RO between the upper case 310 and the lower case 320. By gradually reducing the size from the inlet EN toward the one side of the annular slide bearing, the first seal by the first-stage annular lip portion 342A can surely weaken the momentum such as muddy water, and the first seal can be muddy water. Even if it has passed, even if muddy water that has lost its momentum has passed, intrusion of muddy water that has lost its momentum is reliably prevented by the second and subsequent seals. Or the like can Rukoto, the effect is enormous.

Next, a vehicle thrust slide bearing 400 according to a fourth embodiment of the present invention will be described with reference to FIG.
Here, FIG. 8 is an enlarged cross-sectional view of a main part of a thrust sliding bearing 400 for a vehicle that is a fourth embodiment of the present invention.
The vehicle thrust slide bearing 400 according to the fourth embodiment is obtained by changing the cross-sectional shape of the annular seal elastic member 140 of the vehicle thrust slide bearing 100 according to the first embodiment when viewed from the circumferential direction R. Is common to the thrust sliding bearing 100 for a vehicle according to the first embodiment, the detailed description of common items is omitted, and only the reference numerals in the 400s, which are common to the last two digits, are used.

In the thrust sliding bearing 400 for a vehicle that is the fourth embodiment of the present invention, as shown in FIG. 8, the shapes of the first-stage annular lip portion 442A to the fourth-stage annular lip portion 442D before elastic deformation (one point in FIG. 8). Overlapping portions OL1 to OL4 that overlap with the shape of the outer cylindrical portion 313 of the upper case 310 and the shape of the upper case 310 are provided so as to have the same shape when viewed from the circumferential direction R.
In the present embodiment, the annular seal elastic member 440 is installed between the upper case 410 and the lower case 420.

Thereby, like the first embodiment described above, the rigidity of the annular seal elastic member 440 itself is increased as compared with the rubber of the conventional structure.
That is, it is assembled without an annular cored bar.
Furthermore, it becomes a multi-stage seal structure, and the momentum such as muddy water to invade is reduced at once or in steps.
That is, sufficient sealing performance is ensured.

Next, a thrust sliding bearing for a vehicle 500 that is a fifth embodiment of the present invention will be described with reference to FIG.
Here, FIG. 9 is an enlarged sectional view of a thrust sliding bearing 500 for a vehicle that is a fifth embodiment of the present invention.
In the vehicle thrust slide bearing 500 of the fifth embodiment, the annular seal elastic member 140 of the vehicle thrust slide bearing 100 of the first embodiment is installed not only on the case outer peripheral side but also on the case inner peripheral side from the annular slide bearing piece 130. Since many elements are common to the thrust sliding bearing 100 for the vehicle of the first embodiment, detailed explanations are omitted for the common matters, and only the reference numbers of the 500 series in which the last two digits are common are attached. To do.

In the thrust sliding bearing 500 for a vehicle that is the fifth embodiment of the present invention, as shown in FIG. 9, an outer annular seal elastic member 540A and an inner annular seal elastic member 540B as an annular seal elastic member are connected to the lower case 520. It is installed between the upper case 510.
Of these, the outer annular seal elastic member 540A is the same as the annular seal elastic member 140 of the first embodiment described above, and is installed on the outer peripheral side of the case from the annular slide bearing piece 530.
As a result, a multi-stage seal structure is formed on the outer peripheral side of the annular sliding bearing piece 530 in the clearance path RO between the lower case 520 and the upper case 510, and the momentum of muddy water or the like to enter is reduced at once or in steps. It is.

On the other hand, the inner annular seal elastic member 540 </ b> B is installed closer to the inner periphery of the case than the annular sliding bearing piece 530.
More specifically, the annular inner peripheral base portion 541B of the inner annular seal elastic member 540B is in elastic contact with the lower outer peripheral surface 512c of the inner peripheral cylindrical portion 512 of the upper case 510 and is an annular lip portion 542B. The ring-shaped annular lip portion 542BA to the fourth-stage annular lip portion 542BD are in contact with the upper inner peripheral surface 522b of the inner peripheral cylindrical portion 522 of the lower case 520 in a state of being elastically deformed.
Thus, a multi-stage seal structure is formed on the inner peripheral side of the case from the annular slide bearing piece 530 in the gap path RO between the lower case 520 and the upper case 510, and the momentum of muddy water or the like to enter is at once or stepwise. Reduced.
Thus, both the outer annular seal elastic member 540A and the inner annular seal elastic member 540B may be installed, or only one of them may be installed.

Next, a vehicular thrust slide bearing 600 according to a sixth embodiment of the present invention will be described with reference to FIG.
Here, FIG. 10 is an enlarged cross-sectional view of a thrust sliding bearing 600 for a vehicle that is a sixth embodiment of the present invention.
The vehicle thrust slide bearing 600 of the sixth embodiment is obtained by changing the mounting location of the inner annular seal elastic member 540B of the vehicle thrust slide bearing 500 of the fifth embodiment from the upper case 510 side to the lower case 520 side. Since many elements are common to the thrust sliding bearing 500 for the vehicle according to the fifth embodiment, detailed description of common matters is omitted, and only the reference numerals of the 600 series having the lower two digits are attached.

In the thrust sliding bearing 600 for a vehicle that is the sixth embodiment of the present invention, as shown in FIG. 10, the annular inner peripheral base portion 641 </ b> B of the inner annular seal elastic member 640 </ b> B is connected to the inner peripheral cylindrical portion 622 of the lower case 620. The first-stage annular lip portion 642BA to the fourth-stage annular lip portion 642BD, which are the annular lip portions 642B, elastically contact with the upper outer peripheral surface 622c and are elastically deformed, below the inner peripheral side cylindrical portion 612 of the upper case 610. It is in contact with the inner peripheral surface 612d.
Of course, the inner annular seal elastic member 640B may be configured to be attached to the lower case 620 side.
It goes without saying that the outer annular seal elastic member 640A may be attached to the upper case 610 side.

100, ... 600, thrust thrust bearing 110 for vehicle, 610, upper case 111, upper case base 111a, upper case upper surface 111b, upper case lower surface 112, inner cylinder Portion 112a ... Inner annular groove 112b ... Outer peripheral surface 512c ... Lower outer peripheral surface 612d ... Lower inner peripheral surface 113 ... Outer peripheral cylindrical portion 113a ... Outer annular claw 113b ... Inner periphery Surface 120, ... 620 ... Lower case 121 ... Lower case base 121a ... Base outer peripheral surface 121aa ... Outer annular groove 121b ... Annular flange 121c ... Lower case upper surface 121d ... Inside Peripheral surface 121e ... Lower case lower surface 122 ... Inner peripheral side cylindrical portion 122a ... Inner annular projection 522b ... Upper inner peripheral surface 622c ... Upper outer peripheral surface 123 ... Bearing piece rotation prevention convex part 130, ... 630 ... Annular slide bearing piece (bearing piece)
131 ・ ・ ・ Thrust sliding bearing piece 131a ・ ・ ・ Bearing upper surface 131b ・ ・ ・ Bearing lower surface 132 ・ ・ ・ Radial sliding bearing piece 132a ・ ・ ・ Bearing inner peripheral surface 132b ・ ・ ・ Bearing outer peripheral surface 133 ・ ・ ・ Bearing 440... 440... Annular seal elastic member 540A, 640A... Outer annular seal elastic member 540B and 640B... Inner annular seal elastic member 141. ... (inner annular seal elastic member) annular inner peripheral base 141a ... annular ridge 142 ... annular lip part 542B, 642B ... (inner annular seal elastic member) annular lip part 142A, ... 442A ... 1st stage annular lip part 542BA, 642BA ... (of the inside annular seal elastic member) 1st stage annular lip part 1 42B, ... 442B ... 2nd stage annular lip part 542BB, 642BB ... 2nd stage annular lip part 142C (of the inner annular seal elastic member) ... 442C ... 3rd stage annular lip part 542BC, 642BC .... Third-stage annular lip 142D (for inner annular seal elastic member) 442D ... Fourth-stage annular lip 542BD, 642BD ... (for inner annular seal elastic member) Fourth-stage annular lip AX・ ・ ・ Piston rod axis EN ・ ・ ・ Inlet OL1 to OL4 ・ ・ ・ Overlap part (elastic deformation region)
R ... Circumferential direction RO ... Gap path SS ... Damper coil spring SP ... Spring pad VA ... Vehicle side mounting member (vehicle body side mounting part)
VA1 ... Vehicle side seating surface X ... Radial direction Y ... Axial direction

Claims (7)

An annular upper case that comes into contact with the vehicle body side mounting portion and an annular lower case that overlaps with the upper case so as to be rotatable are provided, and the upper case and the lower case are in direct or indirect contact with each other. In a vehicle thrust bearing that supports a thrust load at the contact point,
An annular seal elastic member that is installed between the upper case and the lower case and seals the contact portion on the case outer peripheral side or the case inner peripheral side is installed in one of the upper case and the lower case. A thrust bearing for a vehicle, comprising: a peripheral base portion; and a plurality of annular lip portions extending from the annular inner peripheral base portion toward the outer periphery of the case and abutting against the other of the upper case and the lower case.   The thrust bearing for a vehicle according to claim 1, wherein a sliding bearing piece made of synthetic resin that supports the thrust load is installed in an annular space formed between the upper case and the lower case.   The vehicular thrust bearing according to claim 1, wherein the annular seal elastic member has an overlap portion in which the plurality of lip portions before elastic deformation abut against the other case and elastically deform. .   The thrust bearing for vehicles according to claim 3 with which said overlap part is greatly provided in order toward said contact location side along a crevice course between said upper case and lower case.   The thrust bearing for vehicles according to claim 3 with which said overlap part is sequentially provided small toward said contact location side along a crevice course between said upper case and lower case.   The vehicle according to any one of claims 1 to 5, wherein an annular protrusion formed on a seal inner peripheral side of the annular inner peripheral base portion is in elastic contact with the upper case or the lower case. Thrust bearings.   The lower case is overlapped with the upper case so as to be relatively rotatable around an axis of a piston rod used for a shock absorber of a vehicle suspension and supports a load from a damper coil spring of the suspension. The thrust bearing for vehicles as described in any one of 6.