KR20180109967A

KR20180109967A - Friction damper

Info

Publication number: KR20180109967A
Application number: KR1020187024690A
Authority: KR
Inventors: 카즈키 하세가와; 토모유키 쿠도; 레이코 이이누마; 마사시 오타키; 야스히코 니시무라
Original assignee: 케이와이비 가부시키가이샤
Priority date: 2017-03-03
Filing date: 2018-02-14
Publication date: 2018-10-08
Also published as: TW201837337A; CN108811507A; JP2018146002A; WO2018159296A1

Abstract

Provided is a friction damper capable of suppressing intrusion of foreign matter into a friction surface. The friction damper 1 has a cylinder 10, a rod 20, a friction member 30, an elastic member 40, and a seal member 50. The cylinder 10 is normally formed. The rod 20 is free to reciprocate in the axial direction, and a part of the rod 20 is accommodated in the cylinder 10. The friction member 30 is disposed inside the cylinder 10 and generates a damping force by a frictional force generated between the outer circumferential surface 20C of the rod 20 by the relative movement between the cylinder 10 and the rod 20 do. The elastic member 40 applies an elastic force in a direction in which the protruding length from the cylinder 10 on the side of the one end 20A of the rod 20 becomes long. The seal member 50 is given an elastic force of the elastic member 40 and is supported by the elastic member 40 to block the gap CP that communicates the outside and the inside of the cylinder 10.

Description

Friction damper

The present invention relates to a friction damper.

Patent Document 1 discloses a conventional frictional damper. The friction damper includes an outer housing, a rod, an internal damping member, and a spring. The outer housing is normally formed. The rod is projected from one end of the outer housing. Further, the rod is inserted into the outer housing freely reciprocally in the axial direction. The internal damping member is provided on the rod so as to be slidable on the inner peripheral surface of the outer housing. The internal damping member generates a damping force by a frictional force generated between the inner circumferential surface of the outer housing and the outer housing by relative movement of the outer housing and the rod. The spring imparts an elastic force between the outer housing and the rod in the direction in which the rod distal end moves away from the outer housing. Accordingly, the friction damper of Patent Document 1 can absorb vibrations and shocks between the outer housing and the rod.

Japanese Patent Specification No. 2006-507460

On the other hand, in a friction damper, if a foreign substance such as a liquid such as water or a contaminating material penetrates into the friction surface, proper damping performance can not be exhibited. Therefore, in the friction damper of Patent Document 1, a dust cap is provided at both ends of the outer housing to prevent foreign matter from entering. However, in the case of a seal member such as the dust cap of Patent Document 1, there is a fear that the seal member is dropped off due to vibration or impact.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described conventional circumstances, and it is an object of the present invention to provide a friction damper capable of favorably suppressing intrusion of foreign matter into a friction surface.

The friction damper of the present invention includes a cylinder, a rod, a friction member, an elastic member, and a seal member. The cylinder is normally formed. The rod is free to reciprocate in the axial direction and partly accommodated in the cylinder. The friction member is disposed inside the cylinder, and a damping force is generated by a frictional force generated between at least one of the inner peripheral surface of the cylinder and the outer peripheral surface of the rod due to the relative movement between the cylinder and the rod. The elastic member is given an elastic force in a direction in which the protruding length from the cylinder at one end side of the rod becomes longer. The seal member is given an elastic force of the elastic member, and is supported by the elastic member to seal a gap communicating between the outside and the inside of the cylinder.

The friction damper of the present invention may include an outer tube. One end of the rod is connected to the bottom of the outer tube and one end of the cylinder is inserted into the cylinder, and a gap is formed between the inner circumferential surface of the cylinder and the outer circumferential surface of the cylinder. Further, the elastic member is disposed on the outer periphery of the cylinder, and can exert an elastic force toward the cross section of the opening side of the outer tube. The seal member is disposed on the outer periphery of the cylinder, and can contact the opening-side end surface of the outer tube and the outer peripheral surface of the cylinder by the elastic member to seal the gap.

In the friction damper of the present invention, a groove portion may be formed in the outer tube. The groove portion is formed at an end portion on the inner circumferential surface side of the opening-side end face of the outer tube and opens to the end face side and the inner circumferential face side of the opening side of the outer tube. And the seal member can be disposed in this groove portion.

The friction damper of the present invention may include an outer tube. One end of the rod is connected to the bottom of the outer tube and one end of the cylinder is inserted into the cylinder, and a gap is formed between the inner circumferential surface of the cylinder and the outer circumferential surface of the cylinder. The elastic member is disposed between the one end of the cylinder and the bottom of the outer tube, and can apply an elastic force toward the end surface of the one end of the cylinder. The seal member is disposed on the inner circumference of the outer tube, and the elastic member contacts the end surface of the one end side of the cylinder and the inner circumferential surface of the outer tube to seal the gap.

The friction damper of the present invention may include a rod guide. The rod guide is configured to seal an opening on one end side of the cylinder and to form a through hole through which the rod can freely reciprocate in the axial direction, and a clearance is formed between the through hole and the outer peripheral surface of the rod. The elastic member is disposed on the outer periphery of the rod protruding from the cylinder, and can exert an elastic force toward the outer end face of the rod guide. The seal member is disposed on the outer periphery of the rod protruding outward from the rod guide, and can contact the outer surface of the rod and the outer peripheral surface of the rod by the elastic member to seal the gap.

In the friction damper of the present invention, the seal member may be disposed in contact with an inclined surface inclined with respect to a direction orthogonal to the axial direction.

In the friction damper of the present invention, the elastic member may be a coil spring. And a washer disposed between the coil spring and the seal member.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side sectional view schematically showing a friction damper of a first embodiment. FIG.
Fig. 2 is an enlarged view of the main part of Fig.
3 is a side sectional view schematically showing the friction damper of the second embodiment.
4 is an enlarged view of the main part of Fig.
5 is a side sectional view that schematically shows a friction damper of the third embodiment.
6 is an enlarged view of the main part of Fig.
Fig. 7 is an enlarged cross-sectional view of a substantial part schematically showing a friction damper of another embodiment, and is a view (another form 1) showing another form of the groove. Fig.
Fig. 8 is an enlarged cross-sectional view of a substantial part schematically showing a friction damper of another embodiment, and is a view (another form 2) showing another form of the groove.
Fig. 9 is an enlarged cross-sectional view of a substantial part schematically showing a friction damper of another embodiment, and is a view (another form 3) showing another form of the groove. Fig.
Fig. 10 is an enlarged cross-sectional view showing a substantial part of a friction damper of another embodiment, showing another form of the groove (another form 4). Fig.
Fig. 11 is an enlarged cross-sectional view of a substantial part schematically showing a friction damper of another embodiment, and is a view (another form 5) showing another form of the groove. Fig.
Fig. 12 is an enlarged cross-sectional view showing a substantial part of a friction damper of another embodiment, showing another form of the groove (another form 6). Fig.
Fig. 13 is an enlarged cross-sectional view of a substantial part schematically showing a friction damper of another embodiment, and is a diagram (another form 1) schematically showing another form of the seal member. Fig.
FIG. 14 is an enlarged cross-sectional view of a substantial part schematically showing a friction damper of another embodiment, and is a diagram (another form 2) schematically showing another form of the seal member. FIG.

Embodiments 1 to 3, in which the friction damper of the present invention is embodied, will be described with reference to the drawings. In the following embodiments, a friction damper used in a caster such as a wheelchair, a baby buggy, and a carriage is exemplified. The friction damper is inserted, for example, into a mechanism portion such as a bracket mounted with a caster and a link mechanism provided between the wheels so as to travel on a road surface having irregularities or steps such as a braille block Vibration damping and shock can be mitigated.

&Lt; Embodiment 1 >

1 and 2, the friction damper 1 according to the first embodiment includes a cylinder 10, a rod 20, a friction member 30, an elastic member 40, and a seal member 50 have. The friction damper 1 also includes an outer tube 60.

The cylinder 10 is formed in a cylindrical shape with both ends opened. A cylindrical rod guide 11 is screwed to one end 10A of the cylinder 10 and an opening on the side of the end 10A is sealed. The rod guide 11, which is normally formed, has an insertion hole 11A penetrating in the axial direction. The rod guide 11 presses the friction member 30 to be described later in the axial direction. A cylinder side joint portion 12 is provided at the other end portion 10B of the cylinder 10. The cylinder side joint part 12, together with a rod side joint part 63 which will be described later, serves as a connection part with another member when assembled to the mechanism part. The cylinder side joint portion 12 is formed with a through hole 12A into which a pin or the like can be inserted. A diameter enlarged portion 10C is formed in the vicinity of the end portion 10A of the cylinder 10 in a larger diameter than other portions. In the enlarged diameter portion 10C, the friction member 30 is received and the rod 20 is inserted. A reduced diameter portion 10D disposed adjacent to the enlarged diameter portion 10C is formed in the vicinity of the end portion 10B of the cylinder 10. The outer circumferential surface 10E on the side of the end 10B of the cylinder 10 is formed larger than the outer circumferential surface 10F on the side of the end 10A. By forming the outer circumferential surface on the side of the end portion 10B in such a manner as to be enlarged, the step portion 10G of the step difference is formed on the outer circumferential surface of the cylinder 10. The stepped portion 10G is provided with a washer 41 for receiving the end portion of the elastic member 40 described later.

The rod 20 is free to reciprocate in the axial direction and partly accommodated in the cylinder 10. The rod 20 is formed in a columnar shape and one end portion 20A is disposed so as to protrude from the end portion 10A of the cylinder 10. [ The rod 20 has one end portion 20A side supported by the insertion hole 11A of the rod guide 11 and the other end portion 20B side supported by the reduced diameter portion 10D of the cylinder 10 have. More specifically, the rod 20 is slidably moved on cylindrical bushes 70, 71 provided on the reduced diameter portion 10D of the cylinder 10 and the insertion hole 11A of the rod guide 11 And is supported by the reduced diameter portion 10D of the cylinder 10 and the rod guide 11 via these two bushes 70,

A piston (21) is provided in the middle of the rod (20) in the axial direction. The piston portion 21 is formed to be larger than the outer diameter of the other portion of the rod 20. The rod 20 places the piston 21 in the enlarged diameter portion 10C of the cylinder 10. A bolt 22 is provided on the other end 20B of the rod 20. The bolt 22 is attached to the end portion 20B of the rod 20 with a washer 23 having an outer diameter larger than the inner diameter of the reduced diameter portion 10D of the cylinder 10. The washer 23 functions to prevent the rod 20 from coming off from the rod guide 11 side by coming into contact with the outer end surface of the reduced diameter portion 10D, As a metal seal for preventing intrusion of foreign matter.

The friction member (30) is disposed inside the cylinder (10). More specifically, the friction member 30 is disposed in the enlarged diameter portion 10C of the cylinder 10. The friction member (30) is pressed in the axial direction by the rod guide (11). The friction member 30 is a member formed of a polyurethane rubber having a hardness of 70 degrees in a cylindrical shape. The outer diameter and the axial length of the friction member 30 are formed to be equal to the inner diameter and the axial length of the enlarged diameter portion 10C and are disposed in the cylinder 10 in a state sandwiched between the enlarged diameter portions 10C have. The outer circumferential surface 21A of the piston portion 21 abuts against the inner circumferential surface 30A of the friction member 30 so as to be slidable. Specifically, the inner circumferential surface 30A of the friction member 30 is formed to have a diameter smaller than the diameter of the outer circumferential surface 21A of the piston portion 21, and the surface pressure of the piston portion 21 And is in contact with the outer peripheral surface 21A.

The friction member 30 generates a damping force by a friction force generated between the outer peripheral surfaces of the rods 20 due to the relative movement between the cylinder 10 and the rods 20. [ In this embodiment, the friction member 30 is configured such that the rod 20 moves relative to the cylinder 10 in the axial direction so that the inner peripheral surface 30A and the outer peripheral surface of the piston 21 in the outer peripheral surface of the rod 20 21A. In other words, the friction surface of the friction damper 1 according to the first embodiment is the inner circumferential surface 30A of the friction member 30 and the outer circumferential surface 21A of the piston 21. The frictional force generated by the sliding movement of these frictional surfaces acts as a damping force for restricting the axial movement of the rod 20.

Further, through holes (not shown) penetrating both end faces in the axial direction are formed in the piston portion 21. When the piston 21 is moved by the expansion and contraction of the friction damper 1 by securing the air between the internal spaces IS of the cylinder 10 separated by the piston 21 by the through holes, Which corresponds to the volume change of the space IS.

The elastic member 40 applies an elastic force in a direction in which the protruding length from the cylinder 10 on the end 20A side of the rod 20 becomes long (left and right direction in Fig. 1). In other words, the elastic member 40 applies an elastic force in a direction to extend the friction damper 1. [ In the present embodiment, the elastic member 40 is disposed on the outer periphery of the cylinder 10 and imparts an elastic force toward the opening side end face 62B of the outer tube 60 described later. Specifically, the elastic member 40 of the present embodiment employs a compression coil spring, and is disposed on the outer periphery of the cylinder 10 in such a manner that the cylinder 10 is inserted into the inner periphery thereof from the end 10A side . At one end of the elastic member 40, there is provided a washer 41 which comes into contact with the stepped portion 10G of the cylinder 10. The other end of the elastic member 40 is provided with a washer 42 which comes into contact with the opening side end face 62B of the outer tube 60 to be described later. The elastic force of the elastic members 40 is applied to the washers 41 and 42 in directions away from each other and the elastic force is transmitted to the cylinder 10 and the outer tube 60 receiving the washers 41 and 42.

2, the washer 42 is formed with an inclined surface 42A. The inclined surface 42A is formed so as to open to the end surface and the inner peripheral surface of the washer 42 in the axial direction outer side (left direction in Fig. 2). In other words, the inclined surface 42A is inclined with respect to the radial direction of the washer 42, which is perpendicular to the axial direction, and is formed so as to face the axially outward side and the inner circumferential direction of the washer 42. [ The inclined surface 42A is formed over the entire circumference of the washer 42 and has a tapered shape which is reduced in diameter in the axial direction from the end on the axially outer side toward the other end as a whole. The inclined surface 42A forms a groove G1 which is a space surrounded by the outer peripheral surface 10F of the cylinder 10 and the opening side end surface 62B of the outer tube 60. [ The groove portion G1 has a triangular cross section.

The seal member 50 is given an elastic force of the elastic member 40 and is supported by the elastic member 40 to block the gap CP that communicates the outside and the inside of the cylinder 10. The clearance CP is a passage communicating the outer space ES of the cylinder 10 with the inner space IS. In the case of the present embodiment, the clearance CP is a gap CP1 between the insertion hole 11A of the rod guide 11 and the outer peripheral surface 20C of the rod 20 (between the bush 71 and the rod 20) And a gap CP3 between the inner space CP2 of the outer tube 60 and the outer peripheral surface 10F of the cylinder 10 and the inner peripheral surface 62C of the cylinder portion 62 of the outer tube 60 . An air passage (not shown) corresponding to a change in volume of the friction damper 1 due to elongation and contraction is connected to the inner space CP2 of the outer tube 60. [

The sealing member 50 is disposed on the outer periphery of the cylinder 10 and the opening side end face 62B of the outer tube 60 and the outer peripheral face 10F of the cylinder 10 are fixed by the elastic member 40, (CP) is blocked. The seal member 50 is disposed in the groove G1. The seal member 50 is an O-ring. The seal member 50 is in contact with an inclined surface 42A which is an inner wall of the groove G1 having a triangular cross section and receives the elastic force of the elastic member 40 via the inclined surface 42A. The seal member 50 is configured such that the opening side end face 62B of the outer tube 60 which is the contact face in the axial direction and the end face 62B of the cylinder 10 which is the contact face in the radial direction, And the gap CP is blocked by the outer circumferential surface 10F. It can be said that the seal member 50 of the present embodiment is disposed at a position between the clearance CP and the outer space ES and blocks the outermost side of the clearance CP. The seal member 50, which is an O-ring, is pressed with a squeeze specified in Japanese Industrial Standard (JIS), for example.

The outer tube 60 is generally formed with a bottom opening at one end. The outer tube 60 has a bottom portion 61 and a barrel portion 62. A rod side joint portion (63) is provided outside the bottom portion (61) of the outer tube (60). The rod side joint part (63) together with the cylinder side joint part (12) serves as a connection part with another member. The rod side joint portion 63 is formed with a through hole 63A through which a pin or the like can be inserted. The rod side joint portion 63 is attached to the rod 20 by a threaded portion 63B threaded into the end portion 20A of the rod 20 by inserting the bottom portion 61 of the outer tube 60. [ In other words, the outer tube 60 is connected to the bottom portion 61 with an end portion 20A which is one end portion of the rod 20. The outer tube 60 is attached to the end portion 20A of the rod 20 in such a manner that the opening side end portion 62A of the cylindrical portion 62 covers the outer peripheral surface 10F side of the end portion 10A of the cylinder 10. In other words, one end portion 10A of the cylinder 10 is inserted into the cylinder portion 62 of the outer tube 60.

Next, the operation and effect of the friction damper 1 according to the first embodiment will be described.

The outer circumferential surface 21A of the piston portion 21 of the rod 20 is pressed against the inner peripheral surface of the friction member 30 when the frictional damper 1 receives the external force, And friction force is generated. This frictional force works as a damping force for damping the shrinking or stretching motion by acting against the elasticity.

The sealing member 50 disposed in the groove G1 moves relative to the cylinder 10 when the friction damper 1 expands and contracts. In other words, the seal member 50 slides in the axial direction about the outer peripheral surface 10F of the cylinder 10 when the friction damper 1 is expanded or contracted. The seal member 50 is supported between the inclined surface 42A and the end surface 62B of the opening side of the outer tube 60 by receiving the elastic force of the elastic member 40. [ Therefore, the seal member 50 is stably supported without falling off, and it surely prevents intrusion of foreign matter.

The seal member 50 is disposed on the outer circumference of the cylinder 10 and is applied with an elastic force of the elastic member 40 toward the opening side end face 62B of the outer tube 60 and the end face 62B and the cylinder 10 while being pressed against the outer circumferential surface 10F to seal the gap CP. Therefore, the clearance (CP) is stably blocked and the intrusion of the foreign matter into the clearance (CP) is prevented. The seal member 50 closes the gap CP at a position closest to the outer space ES which is the entrance of the gap CP and has the largest distance to the inner space IS of the cylinder 10 have. Therefore, even if the foreign matter penetrates into the clearance CP beyond the seal member 50, reaching the friction surface in the cylinder 10 is suppressed.

As described above, the friction damper 1 of the first embodiment includes the cylinder 10, the rod 20, the friction member 30, the elastic member 40, and the seal member 50. The cylinder 10 is normally formed. The rod 20 is free to reciprocate in the axial direction, and a part of the rod 20 is accommodated in the cylinder 10. The friction member 30 is disposed inside the cylinder 10 and a damping force is generated by a frictional force generated between the outer circumferential surface 21A of the rod 20 by the relative movement between the cylinder 10 and the rod 20 do. The elastic member 40 applies an elastic force in a direction in which the protruding length from the cylinder 10 at the one end 20A side of the rod 20 becomes long. The seal member 50 is given an elastic force of the elastic member 40 and is supported by the elastic member 40 to block the gap CP that communicates the outside and the inside of the cylinder 10.

With such a configuration, the friction damper 1 receives the elastic force of the elastic member 40 by the sealing member 50, and the sealing member 50 is supported in the state where the elastic force is applied. Therefore, it is possible to reliably prevent the seal member 50 from falling off due to collision or vibration. As a result, the sealed state can be reliably maintained by the seal member 50.

Therefore, the friction damper 1 can suppress the intrusion of foreign matter into the friction surface.

The friction damper 1 also includes an outer tube 60. One end 20A of the rod 20 is connected to the bottom 61 and the other end of the cylinder 10 is connected to the cylinder 62 10A are inserted and a clearance CP3 is formed between the inner peripheral surface of the cylinder portion 62 and the outer peripheral surface 10F of the cylinder 10. [ The elastic member 40 is disposed on the outer periphery of the cylinder 10 and exerts an elastic force toward the opening side end face 62B of the outer tube 60. [ The seal member 50 is disposed on the outer periphery of the cylinder 10 and contacts the opening side end surface 62B of the outer tube 60 and the outer peripheral surface 10F of the cylinder 10 by the elastic member 40, (CP). This makes it possible to further increase the length of the gap CP, which is the path of the foreign object penetration, for example, as compared with the case where the seal member is disposed on the inner periphery of the cylinder. This prevents the foreign matter that has passed through the seal member 50 from reaching between the inner peripheral surface of the friction member 30 which is the friction surface in the cylinder 10 and the outer peripheral surface 21A of the piston portion 21 of the rod 20 .

The seal member 50 is disposed in contact with the inclined surface 42A which is inclined with respect to the direction orthogonal to the axial direction. Therefore, the elastic force by the elastic member 40 can be suitably converted not only in the axial direction but also by the force pressing the seal member 50 in the radial direction. As a result, the seal member 50 can be positively pressed on the opening side end face 62B of the outer tube 60 as the contact face in the axial direction and the outer peripheral face 10F of the cylinder 10 as the contact face in the radial direction .

The elastic member 40 is a coil spring. And a washer 42 disposed between the elastic member 40, which is a coil spring, and the seal member 50. Therefore, the elastic force can be given to the seal member 50 as compared with the case where the seal member 50 is directly applied with the elastic force.

&Lt; Embodiment 2 >

Next, the second embodiment will be described with reference to FIG. 3, FIG. 4, and the like.

The friction damper 201 according to the second embodiment shown in Figs. 3 and 4 is different from the friction damper 1 according to the first embodiment in that the elastic member 240 and the seal member 250 are arranged. Parts having substantially the same configuration and function as those in Embodiment 1 are denoted by the same reference numerals as those in Embodiment 1, and detailed description thereof is omitted.

As shown in Figs. 3 and 4, in the friction damper 201 of the second embodiment, the elastic member 240 employs a compression coil spring. The elastic member 240 is arranged in such a manner that the rod 20 is inserted into the inner periphery of the elastic member 240 from the end 20A side and the outer periphery thereof is covered with the barrel portion 62 of the outer tube 60. [ One end of the elastic member 240 is in contact with the bottom portion 61 of the outer tube 60. A washer 242 is provided at the other end of the elastic member 240 to abut the end surface 10H of the end portion 10A of the cylinder 10. The elastic force of the elastic member 40 is applied to the washer 242 in a direction away from the bottom portion 61 of the outer tube 60 and the elastic force is transmitted to the cylinder 10 receiving the washer 242.

4, the washer 242 is formed with an inclined surface 242A. The inclined surface 242A is formed to open in the axial direction inner side of the washer 242 (the right side direction in Fig. 4) and the outer peripheral surface. In other words, the inclined surface 242A is inclined with respect to the radial direction of the washer 242 which is orthogonal to the axial direction, and is formed so as to face the inside and the outer circumferential direction of the washer 242 in the axial direction. The inclined surface 242A is formed over the entire circumference of the washer 242 and is formed as a tapered surface which is diametrically enlarged in the axial direction from the axially inner end face to the other end. The inclined surface 242A forms a groove portion G2 which is a space surrounded by the end surface 10H side end 10H of the cylinder 10 and the inner circumferential surface 62C of the cylinder portion 62 of the outer tube 60. [ The groove portion G2 has a triangular section in the same manner as the groove portion G1 of the first embodiment.

The elastic force of the elastic member 240 is given to the seal member 250. The seal member 250 is supported by the elastic member 240 to block the gap CP. The seal member 250 is disposed on the inner circumference of the cylindrical portion 62 of the outer tube 60 and is given an elastic force of the elastic member 240 toward the end face 10H of the end portion 10A side of the cylinder 10 have. More specifically, the seal member 250 is disposed in the groove portion G2. The seal member 250 is the same O-ring as the seal member 50 of the first embodiment. The seal member 250 is in contact with an inclined surface 242A which is an inner wall of the groove G2 having a triangular section and receives the elastic force of the elastic member 240 via the inclined surface 242A. The seal member 250 receives an elastic force of the elastic member 240 via the inclined surface 242A and thereby the end surface 10H side of the cylinder 10 which is the contact surface in the axial direction and the end surface 10H of the end surface 10A in the axial direction, The clearance CP is blocked while being pressed against the inner circumferential surface 62C of the cylindrical portion 62 of the outer tube 60 which is the contact surface.

Next, the operation and effect of the friction damper 201 according to the second embodiment will be described.

The outer peripheral surface 21A of the piston portion 21 of the rod 20 is pressed against the outer peripheral surface 21A of the rod 20 when the frictional damper 201 is contracted due to an external force or the external force is removed to expand the elastic member 240 by the elastic force of the elastic member 240 A frictional force is generated by sliding the inner peripheral surface 30A of the friction member 30. This frictional force works as a damping force for damping the shrinking or stretching motion by acting against the elasticity.

The seal member 250 disposed in the groove G2 relatively moves with respect to the outer tube 60 when the friction damper 201 expands and contracts. In other words, the seal member 250 slides axially in the inner peripheral surface 62C of the cylindrical portion 62 of the outer tube 60 when the friction damper 201 is expanded or contracted. The seal member 250 is held between the inclined surface 242A and the end face 10H of the end portion 10A of the cylinder 10 and is supported by the elastic force of the elastic member 240. [ Therefore, the seal member 250 is stably supported without falling off, and the intrusion of foreign matter is reliably prevented.

The seal member 250 is disposed on the inner circumference of the cylindrical portion 62 of the outer tube 60 and is given an elastic force of the elastic member 240 toward the end surface 10H of the end portion 10A of the cylinder 10 The inner circumferential surface 62C of the outer tube 60 and the end surface 10H side end 10H of the cylinder 10 while being pressed against each other to seal the gap CP. Therefore, the clearance (CP) is stably blocked to prevent intrusion of foreign matter into the clearance (CP).

The frictional damper 201 having such a structure receives the elastic force of the elastic member 240 by the sealing member 250, and the sealing member 250 is supported in the state of receiving the elastic force. Therefore, it is possible to reliably prevent the seal member 250 from falling off due to impact or vibration. As a result, the sealed state can be reliably maintained by the seal member 250. Therefore, the friction damper 201 can suppress the intrusion of foreign matter into the friction surface in the same manner as the friction damper 1 of the first embodiment.

The elastic member 240 is disposed between the end portion 10A of the cylinder 10 and the bottom portion 61 of the outer tube 60 so that the friction damper 201 can be elastically deformed at one end portion 10A of the cylinder 10 To the side end face 10H. The seal member 250 is disposed on the inner periphery of the outer tube 60 and contacts the end face 10H side end 10H of the cylinder 10 and the inner peripheral face of the outer tube 60 by the elastic member 240 It is blocking the gap (CP). Therefore, the gap CP can be sealed by the seal member 250. Further, since the elastic members 240 are arranged side by side in the axial direction of the cylinder 10, the size of the friction damper in the radial direction can be made smaller than in the case where the elastic members are disposed on the outer circumference of the cylinder.

The seal member 250 is disposed in contact with the inclined surface 242A which is inclined with respect to the direction orthogonal to the axial direction. Therefore, the elastic force by the elastic member 240 can be converted not only in the axial direction but also in a force that presses the seal member 250 in the radial direction. As a result, the seal member 250 is inserted into the end face 10A side end face 10H of the cylinder 10 and the inner peripheral face 62C of the cylinder portion 62 of the outer tube 60, It is possible to press each of them appropriately.

The elastic member 240 is a coil spring. And a washer 242 disposed between the elastic member 240, which is a coil spring, and the seal member 250. Therefore, elastic force can be given to the seal member 250 more favorably than when the elastic force is directly applied to the elastic member 240.

&Lt; Embodiment 3 >

Next, the third embodiment will be described with reference to Figs. 5, 6, and the like.

The friction damper 301 according to the third embodiment shown in Figs. 5 and 6 is different from the friction damper 1 according to the first embodiment in that the elastic member 340 and the seal member 350 are arranged. Parts having substantially the same configuration and function as those in Embodiment 1 are denoted by the same reference numerals as those in Embodiment 1, and detailed description thereof is omitted.

5 and 6, in the friction damper 301 of the third embodiment, the elastic member 340 employs a compression coil spring, and like the elastic member 240 of the second embodiment, (20) is inserted from the end (20A) side and the outer periphery thereof is covered with the cylindrical portion (62) of the outer tube (60). One end of the elastic member 340 abuts against the bottom portion 61 of the outer tube 60 and the other end of the elastic member 340 abuts against the end surface 10A of the cylinder 10 by a washer 342 ). The elastic force of the elastic member 40 is applied to the washer 342 in a direction away from the bottom portion 61 of the outer tube 60 and the elastic force is transmitted to the cylinder 10 receiving the washer 342.

6, the washer 342 is formed with an inclined surface 342A. The inclined surface 342A is formed to open in the axial direction inner side (the right side direction in Fig. 6) and the inner peripheral surface of the washer 342. [ In other words, the inclined surface 342A is inclined with respect to the radial direction of the washer 242 which is orthogonal to the axial direction, and is formed to face the inside and the inside of the washer 242 in the axial direction. The inclined surface 342A is formed over the entire circumference of the washer 342, and as a whole, forms a tapered shape which is axially reduced in the axial direction from the axially inner end face to the other end. The inclined surface 342A forms a groove G3 which is a space surrounded by the outer end surface 11B of the rod guide 11 and the outer peripheral surface of the rod 20. [ The groove portion G3 has a triangular cross section in the same manner as the groove portions G1 and G2 in the first and second embodiments.

The seal member 350 applies an elastic force to the elastic member 340. The seal member 350 is supported by the elastic member 340 to block the gap CP. The seal member 350 is disposed on the outer periphery of the rod 20 and is provided with an elastic force of the elastic member 240 toward the outer end face 11B of the rod guide 11. More specifically, the seal member 350 is disposed in the groove portion G3. The seal member 350 is the same O-ring as the seal members 50 and 250 of the first and second embodiments. The seal member 350 is in contact with an inclined surface 342A which is an inner wall of the groove G3 having a triangular section and receives the elastic force of the elastic member 340 via the inclined surface 342A. The seal member 350 receives the elastic force of the elastic member 340 via the inclined surface 342A and thereby the outer end surface 11B of the rod guide 11 which is the abutting surface in the axial direction, (CP) is pressed while being pressed against the outer circumferential surface (20C) of the valve seat (20).

Next, the operation and effect of the friction damper 301 according to the third embodiment will be described. When the frictional damper 301 is contracted due to an external force or the external force is removed and it is elongated by the elastic force of the elastic member 340, the outer peripheral surface 21A of the piston portion 21 of the rod 20 is friction Friction occurs on the inner peripheral surface 30A of the member 30 by sliding. This frictional force works as a damping force for damping the motion of contraction or elongation by acting against the elasticity.

The sealing member 350 disposed in the groove G3 moves relative to the rod 20 when the friction damper 301 expands and contracts. In other words, the seal member 350 slides in the axial direction about the outer peripheral surface of the rod 20 when the friction damper 301 is expanded or contracted. The seal member 350 is supported between the inclined surface 342A and the outer end surface 11B of the rod guide 11 by receiving the elastic force of the elastic member 340. [ As a result, the seal member 350 is stably maintained without falling off, and the intrusion of foreign matter is surely prevented.

The seal member 350 is disposed on the outer periphery of the rod 20 so that an elastic force of the elastic member 340 is applied toward the outer end face 11B of the rod guide 11, Is pressed against the outer end face (11B) of the guide (11) to seal the gap (CP). Therefore, the clearance (CP) is stably blocked and the intrusion of the foreign matter into the clearance (CP) is prevented.

As described above, the friction damper 301 of the third embodiment receives the elastic force of the elastic member 340 by the sealing member 350, and the sealing member 350 is supported in the state where the elastic force is applied. Therefore, it is possible to reliably prevent the seal member 350 from falling off due to impact or vibration. As a result, the sealed state can be reliably maintained by the seal member 350. Therefore, the frictional damper 301 can suppress the intrusion of foreign matter into the frictional surface in the same manner as the frictional damper 1, 201 of the first and second embodiments.

The friction damper 301 is provided with a rod guide 11. The rod guide 11 blocks the opening on the side of the end portion 10A of the cylinder 10 and causes the rod 20 to reciprocate in the axial direction And a clearance CP1 is formed between the insertion hole 11A and the outer peripheral surface 20C of the rod 20. [ The elastic member 340 is disposed on the outer periphery of the rod 20 protruding from the cylinder 10 and exerts an elastic force toward the outer end face 11B of the rod guide 11. The seal member 350 is disposed on the outer periphery of the rod 20 protruding outward from the rod guide 11 and the outer end face 11B of the rod guide 11 and the rod 20 And the gap CP is sealed. Since the elastic members 340 are arranged side by side in the axial direction of the cylinder 10 as described above, the size of the friction damper in the radial direction can be made smaller than that in the case where the elastic members 340 are disposed on the outer circumference of the cylinder 10 .

The present invention is not limited to the first to third embodiments described with reference to the above description and drawings, for example, the following embodiments are also included in the technical scope of the present invention.

(1) In Embodiments 1 to 3, the O-ring is exemplified as the seal member, but the present invention is not limited to this and other seal members may be employed. Further, the seal member is not limited to the seal member having the same sectional shape as the O-ring, but may be a seal member having other cross-sectional shapes such as an elliptical cross-section, a half-circular cross-section, a cross-sectional rectangular cross section or a U-cross section.

(2) In the first to third embodiments, the groove portions are formed in the washer respectively, but this is not essential. The groove portion may be formed on the member side receiving the elastic force of the elastic member through the washer. The groove portion G4 may be formed in the end surface 462B of the outer tube 460 that receives the elastic force of the elastic member 40 via the washer 442 as shown in Fig. 8 and 9, the end face 510H of the cylinder 510 receiving the elastic force of the elastic members 240 and 340 via the washers 542 and 642, the end face 510H of the rod guide 611, The grooves G5 and G6 may be formed in each of the grooves G5 and G6. It is also possible to form a groove portion formed over two members like the groove portion G7 formed over both of the washer 42 and the outer tube 460 shown in Fig. Further, the groove portion may be directly formed on the elastic member like the groove portion G8 formed in the end portion of the elastic member 840 shown in Fig. These groove portions can have the same triangular cross section as the groove portions of Embodiments 1 to 3 and can form an inclined surface in contact with the seal member.

(3) In Embodiments 1 to 3, the form of forming the groove portion of the triangular cross section is illustrated, but this is not essential. Sectional shape of the groove portion is not limited to a triangular shape and may be, for example, a groove portion G9 in a rectangular cross section shown in Fig. 12A, a groove portion G10 in an end fan shape shown in Fig. 12B, Or a groove portion G11 having a cross-sectional shape in which a rectangular upper end surface and an inclined surface are combined as shown in Fig.

(4) In Embodiments 1 to 3, the seal member is arranged in the groove portion, but this is not essential. For example, as shown in Fig. 13, as shown in Fig. 14, a seal member 1250 having an annular shape identical to that of the washer, and a seal member 1340 formed by coating an elastic member 1340 with a resin that is a material of the seal member The seal member may be disposed without providing the groove portion such as the member 1350. [

(5) In the first to third embodiments, a space inside the outer tube is connected to an air passage (not shown) corresponding to a volume change caused by the expansion and contraction of the friction damper, but this is not essential. When the ventilation path is provided, for example, in order to suppress intrusion of foreign matter, a ventilation hole which is connected at the other end side of the rod to secure a distance from the outside, and a ventilation hole or a bottom portion of the outer tube, A ventilation hole formed by a plurality of ventilation holes can be adopted.

(6) In Embodiments 1 to 3, a washer is attached to the other end of the rod, and the metallic seal is used to prevent foreign matter from entering the cylinder. However, this is not essential. When a seal is provided at the other end of the rod, it is not limited to this washer, but another type of seal member such as an O-ring may be provided.

(7) In the first to third embodiments, the washer which receives the end face of the elastic member or the washer attached to the other end of the rod is exemplified. However, instead of these washers, a member such as a spacer, May be used.

(8) In the first to third embodiments, the damping force is generated by the frictional force generated between the outer circumferential surfaces of the rods. However, the frictional force is generated between the inner circumferential surfaces of the cylinder, that is, Or a form in which a frictional force is generated between both the inner circumferential surface of the cylinder and the outer circumferential surface of the rod, that is, the frictional member may be provided so as to be slidably movable with respect to both the cylinder and the rod.

(9) In the third embodiment, the friction damper has an outer tube having a bottom portion and a cylindrical portion, the bottom portion of which is connected to one end of the rod, and an elastic member disposed on the outer periphery of the rod. And the resilient force of the elastic member is given in the direction in which the protruding length from the cylinder at one end of the rod is lengthened. However, in this case, the cylinder portion of the outer tube is not essential. In other words, instead of the shape having the outer tube, for example, a shape having another member such as a disc-like member connected to one end of the rod and receiving elastic force of the elastic member, or a shape having one end of the rod, .

(10) In the first to third embodiments, the rod guide is provided. However, the rod guide does not necessarily need to have a function of guiding the rod. In other words, as long as the rod guide is provided with a through hole through which the rod can be reciprocated in the axial direction while sealing the opening on one end side of the cylinder and a gap is formed between the through hole and the outer peripheral surface of the rod, Is not particularly limited. For example, the rod guide may be a shape formed by bending an end portion of a cylinder inwardly or the like. Even in such a rod guide, a seal member can be interposed between the rods.

(11) In the first to third embodiments, the elastic member is provided with a sealing member provided with an elastic force. However, in addition to the above, the inner peripheral surface of the insertion hole of the rod guide and the outer peripheral surface of the rod, And another seal member disposed between the inner circumferential surface and the outer circumferential surface of the rod may be further provided.

(12) In the first to third embodiments, the coil spring as the elastic member is illustrated, but this is not essential. In the case where the coil spring is provided, it is preferable that the washer provided between the coil spring and the seal member is provided as shown in each of the above embodiments. For example, there are several types of end portions of a coil spring, such as an open end, a closed end, and the presence or absence of grinding. When these end portions are directly brought into direct contact with the seal member, elasticity is not uniformly applied in the radial direction of the seal member, for example, a portion that is not contacted occurs or an unbalanced contact area occurs. However, by interposing the washer, uniform elasticity can be imparted to the seal member by the washer.

1, 201, 301 ... Friction damper
10, 510 ... cylinder
10A ... One end of the cylinder
10B ... The other end of the cylinder
10C ... Diameter portion
10D ... Axial neck
10E ... The outer peripheral surface of the other end side of the cylinder
10F ... The outer peripheral surface of one end side of the cylinder
10G ... Stepped portion
10H, 510H ... Section of one end side of the cylinder
11, 611 ... Road guide
11A ... Drill hole
11B, 611B ... Section of the outer side of the rod guide
12 ... The cylinder-
12A ... Through hole
20 ... road
20A ... One end of the rod
20B ... The other end of the rod
20C ... The outer circumference of the rod
21 ... Piston portion
21A ... The outer peripheral surface of the piston portion
22 ... volt
23 ... washer
30 ... Friction member
30A ... The inner peripheral surface of the friction member
40, 240, 340, 840, 1340 ... Elastic member
41, 42, 242, 342, 442, 542, 642 ... washer
42A, 242A, 342A ... incline
50, 250, 350, 1250, 1350 ... Seal member
60, 460 ... Outer tube
61 ... The bottom of the outer tube
62 ... The tubing of the outer tube
62A ... The opening-side end of the outer tube
62B, 462B ... The open side of the outer tube
62C ... The inner peripheral surface of the tube portion of the outer tube
63 ... The rod-
63A ... Through hole
63B ... Thread
70, 71 ... bush
CP ... gap
CP1 ... Clearance between rod guide and rod
CP2 ... The space in the outer tube
CP3 ... The gap between the outer circumferential surface of the cylinder and the inner circumferential surface of the outer tube
ES ... The outer space of the cylinder
G1 to G11 ... Groove
IS ... The inner space of the cylinder

Claims

A normal cylinder,
A rod which is free to reciprocate in the axial direction, a part of which is housed in the cylinder,
A friction member disposed inside the cylinder and generating a damping force by friction generated between at least one of an inner circumferential surface of the cylinder and an outer circumferential surface of the rod by a relative movement between the cylinder and the rod;
An elastic member that applies an elastic force in a direction in which the protruding length from the cylinder at one end side of the rod becomes longer,
A sealing member which is provided with an elastic force of the elastic member and which is supported by the elastic member to seal a gap communicating between the outside and the inside of the cylinder,
And a friction damper.

The method according to claim 1,
And a bottomed normal outer tube connected to one end of the rod at the bottom and inserted into one end of the cylinder in the cylinder and forming the clearance between the inner circumferential surface of the cylinder and the outer circumferential surface of the cylinder,
Wherein the elastic member is disposed on an outer periphery of the cylinder and applies an elastic force toward an opening side end face of the outer tube,
Wherein the seal member is disposed on the outer periphery of the cylinder and abuts on an opening side end surface of the outer tube and an outer peripheral surface of the cylinder by the elastic member to seal the gap.

3. The method of claim 2,
Wherein the outer tube is formed with a groove portion in which an end surface of the outer tube has an end surface on the inner circumferential surface side of the opening and opens to the opening side and the inner surface side and in which the sealing member is disposed.

The method according to claim 1,
And a bottomed normal outer tube connected to one end of the rod at the bottom portion and inserted into one end of the cylinder in the cylinder portion and forming the clearance between the inner circumferential surface of the cylinder portion and the outer circumferential surface of the cylinder,
The elastic member is disposed between one end of the cylinder and the bottom portion of the outer tube and applies an elastic force toward the one end side end face of the cylinder,
Wherein the seal member is disposed on an inner circumference of the outer tube and contacts the end surface of the one end of the cylinder and the inner circumferential surface of the outer tube by the elastic member to seal the gap.

The method according to claim 1,
And a rod guide having an opening formed at one end of the cylinder and having a through hole through which the rod can reciprocate freely in the axial direction, the rod guide forming the gap between the insertion hole and the outer peripheral surface of the rod However,
Wherein the elastic member is disposed on the outer periphery of the rod projecting from the cylinder and applying an elastic force toward an outer end surface of the rod guide,
Wherein the sealing member is disposed on an outer periphery of the rod protruding outward from the rod guide and abuts on an outer end face of the rod and an outer peripheral face of the rod by the elastic member to seal the gap. Friction damper.

6. The method according to any one of claims 1 to 5,
Wherein the seal member is disposed in contact with an inclined surface inclined with respect to a direction orthogonal to the axial direction.

6. The method according to any one of claims 1 to 5,
Wherein the elastic member is a coil spring,
And a washer disposed between the coil spring and the seal member.

The method according to claim 6,
Wherein the elastic member is a coil spring,
And a washer disposed between the coil spring and the seal member.