JP2012037060A - Rotary friction damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary friction damper which can obtain frictional force stable and relatively large, and be miniaturized.SOLUTION: The rotary friction damper 1 is equipped with: a synthetic resin inner cylinder 8 which integrally has an inner cylinder body 5, which is fixed so that it is not rotated in an R direction in a cylindrical inner circumferential surface 2 or outer circumferential surface 4 of rotary shaft 3, and ring-like projection 7 which is projected in radial and outward direction from an outer circumferential surface 6 of the inner cylinder body 5; and synthetic resin outer cylinder 13 which has a recess 9, which receives the projection 7 of the inner cylinder 8 and is recessed in the radial and outward direction, and recess 11 which specifies the recess 9 and contacts with an outer surface 10 of the projection 7 in an inner circumferential surface 12. Furthermore, the outer cylinder 13 rotatably supports the inner cylinder 8 in the R direction on the inner circumferential surface 12, and is fitted and fixed so that it may not be rotated in the R direction in its outer circumferential surface 14 or inner circumferential surface 16 of a housing 15.

Description

  The present invention relates to a rotary friction damper that provides damping due to friction with respect to rotation of a rotating shaft such as a steering shaft, door check, trunk or bonnet hinge.

  As rotary dampers, those using a fluid called a viscous damper and those using friction are known.

JP 2001-336523 A JP-A-9-42271 JP-A-7-26825

  While a rotary damper using a fluid can ensure a large attenuation, it has a problem of sealing performance such as fluid leakage and a temperature dependency problem that the attenuation varies greatly depending on the temperature difference.

  The rotary damper using friction does not need to consider the sealing performance and is not easily affected by temperature change with respect to damping. However, the rotary friction damper described in Patent Document 1 requires a relatively large friction surface. As a result, it is difficult to reduce the size, and it is difficult to obtain a stable friction force in the rotary friction dampers described in Patent Documents 2 and 3.

  The present invention has been made in view of the above-mentioned points, and the object of the present invention is to obtain a stable and relatively large frictional force, and thus a rotary friction that can be reduced in size. To provide a damper.

  The rotary friction damper of the present invention includes a synthetic resin inner cylinder that has one of a radially protruding protrusion and a radially recessed recess that receives the protrusion and is fixed to the rotating shaft. A radially projecting protrusion and the other of the radially recessed recesses for receiving the protrusion and rotatably supporting the inner cylinder, and a synthetic resin outer cylinder fixed to the housing. And the protrusion is in contact with the recess surface defining the recess at its outer surface.

  According to the rotary friction damper of the present invention, it has a protrusion protruding in the radial direction and a recess that receives the protrusion, and the outer surface of the protrusion is in contact with the recess surface that defines the recess. Thus, a stable and relatively large frictional force can be obtained, and thus the size can be reduced.

  The synthetic resin as a material for forming the inner cylinder and the outer cylinder is preferably a material having excellent wear resistance and a stable frictional force. Specifically, polyacetal resin, polyamide resin, polybutylene terephthalate resin, liquid crystal polyester resin And a synthetic resin containing at least one of a modified polyphenylene ether resin, a polyphenylene sulfide resin, a polyether sulfone resin, and a polyether ketone resin. These synthetic resins may be blended with various fillers. And the friction characteristic obtained can be adjusted by changing the combination of the synthetic resin which forms an inner cylinder and an outer cylinder, and the filler to mix | blend.

  In the present invention, the inner cylinder may include a protrusion protruding in the radially outward direction, and the outer cylinder may include a recess that receives the protrusion and is recessed in the radially outward direction. Alternatively, the outer cylinder may include a protrusion protruding in the radially inward direction, and the inner cylinder may include a recess that receives the protrusion and is recessed in the radially inward direction.

  In a preferred example, the protrusion has at least one annular protrusion having a trapezoidal (wedge-shaped) cross section, and the recess has an annular shape having a shape complementary to the protrusion. Has a recess. There may be one such protrusion, but there may be a plurality of protrusions arranged along the axial direction. In order to receive a part, it is good to be a plurality arranged along the axial direction.

  In one example, the outer cylinder is divided into two parts in the axial direction. In the outer cylinder that is divided into two parts and includes one divided body in the axial direction and the other divided body in the axial direction, The divided body and the other divided body face each other at their divided surfaces and are connected to each other by a connecting means. In this example, each divided body preferably has a flange on the divided surface side. In addition, the connecting means includes a ring body having a freely expandable diameter that elastically holds both flange portions.

  In another example, the outer cylinder is divided into at least two parts in the circumferential direction, and the outer cylinder is divided into at least two parts and includes one divided body and the other divided body. The body and the other divided body face each other at their divided surfaces and are connected to each other by connecting means. In this example, preferably, each divided body has at least one circumferentially extending on the outer peripheral surface. A semi-cylindrical portion having a groove is provided, and the connecting means includes an elastic annular body extending in the circumferential direction through each groove of the semi-cylindrical portion.

  The elastic annular body that clamps the inner cylinder through the divided body may preferably be a so-called O-ring made of natural rubber or synthetic rubber, or other thermoplastic synthetic resin having elasticity, such as a polyester elastomer. Also good.

  In another preferred example, the protrusion has a spiral protrusion, the recess has a spiral recess that receives the spiral protrusion, and the inner peripheral surface of the outer cylinder is the outer peripheral surface thereof. In contrast, it is movable in the axial direction.

  When the projection having the spiral projection and the recess having the spiral recess for receiving the spiral projection are provided, the outer surface of the spiral projection and the recess defining the spiral recess are provided. It is preferable that a large frictional force can be obtained by friction with the surface, and that further downsizing can be achieved.

  A preferable example of the spiral protrusion is an external thread, and a preferable example of the spiral recess is an internal thread that is screwed into the external thread.

  One preferred example of the outer cylinder whose inner peripheral surface is movable in the axial direction with respect to the outer peripheral surface is a cylindrical body made of synthetic resin on the inner diameter side that rotatably supports the inner cylinder on the inner peripheral surface; A cylindrical body made of synthetic resin on the outer diameter side having an inner peripheral surface that is slidably contacted at least in the axial direction on the outer peripheral surface of the cylindrical body and has an outer peripheral surface fixed to the housing.

  According to the outer cylinder provided with the cylindrical body on the inner diameter side and the outer diameter side that are in sliding contact with each other in the axial direction between the outer peripheral surface and the inner peripheral surface, since the frictional force at the sliding contact portion can be used, A large frictional force can be obtained, and thus further downsizing can be achieved.

  In a preferred example, the cylinder on the inner diameter side has at least one slit extending in the axial direction from one end surface, and in this case, the cylinder on the inner diameter side is at least one extending in the circumferential direction on the outer peripheral surface. It is good to have one annular groove and to be elastically reduced in diameter by the elastic annular body with which the said annular groove was mounted | worn.

  The inner cylinder can be tightened with the tightening margin of the inner diameter side cylinder when the inner diameter side cylinder is elastically reduced in diameter by the elastic annular body. Therefore, it is possible to obtain a larger frictional force and to further reduce the size.

  The elastic annular body for tightening the rotation axis of the inner cylinder via the inner diameter side cylindrical body is preferably a so-called O-ring made of natural rubber or synthetic rubber, like the elastic annular body for tightening the inner cylinder via the divided body. It may be a thermoplastic synthetic resin having other elasticity, for example, a polyester elastomer.

  Such an elastic annular body is not elastically contacted with the inner peripheral surface of the outer diameter side cylindrical body, or alternatively, is in contact with the inner peripheral surface of the outer diameter side cylindrical body. It may be mounted in the annular groove of the cylindrical body on the inner diameter side so as to be in contact.

  When the elastic annular body is brought into elastic contact with the inner peripheral surface of the outer diameter side cylindrical body, the frictional force between the elastic annular body and the outer diameter side cylindrical body can be utilized, thereby obtaining a larger frictional force. Thus, further downsizing can be achieved.

  According to the present invention, it is possible to provide a rotary friction damper that can obtain a stable and relatively large frictional force and can be downsized.

FIG. 1 is a cross-sectional explanatory view taken along the line II of FIG. 2 showing an example of a preferred embodiment of the present invention. FIG. 2 is an explanatory left side view of the example shown in FIG. FIG. 3 is an exploded explanatory view of the inner cylinder and the outer cylinder in the example shown in FIG. FIG. 4 is an explanatory diagram of the torus of the example shown in FIG. 1, (a) is a front explanatory diagram, and (b) is a right side explanatory diagram of (a). FIG. 5 is a cross-sectional view taken along line VV shown in FIG. 6 of another example of the preferred embodiment of the present invention. FIG. 6 is an explanatory diagram of the left side of the example shown in FIG. FIG. 7 is an explanatory front view of the inner cylinder of the example shown in FIG. FIG. 8 is an explanatory front view of the rotary friction damper of the example shown in FIG. FIG. 9 is a cross-sectional view taken along line XX of FIG. 10 showing still another example of the preferred embodiment of the present invention. FIG. 10 is a left side explanatory view of the example shown in FIG. FIG. 11 is an explanatory perspective view of a cylindrical body on the outer diameter side in the example shown in FIG. 12 is an explanatory diagram on the right side of the cylindrical body on the outer diameter side in the example shown in FIG. FIG. 13 is an explanatory front view of the inner diameter side cylinder of the example shown in FIG. 9. FIG. 14 is a left side view of the inner diameter side cylinder shown in FIG. FIG. 15 is an explanatory diagram on the right side of the inner diameter side cylinder shown in FIG. 13. 16 is a cross-sectional view taken along the line XVI-XVI in FIG. 14 of the cylindrical body on the inner diameter side shown in FIG. 13. FIG. 17 is an explanatory front view of the inner cylinder of the example shown in FIG. 9. FIG. 18 is an explanatory diagram of still another example of the preferred embodiment of the present invention. FIG. 19 is an explanatory front view of the cylindrical body on the inner diameter side of the example shown in FIG. 18 and the elastic annular body attached to the cylindrical body. FIG. 20 is an explanatory diagram of still another example of the preferred embodiment of the present invention.

  The invention will now be described in more detail with reference to the preferred embodiment examples shown in the drawings. The present invention is not limited to these examples.

  1 to 4, the rotary friction damper 1 of this example has a cylindrical inner peripheral surface 2 on a cylindrical outer peripheral surface 4 of a rotary shaft 3 in a direction around an axis O, that is, a rotational direction. The inner cylinder body 5 fixed so as not to rotate in the R direction, which is the circumferential direction, and a synthetically integrated ring-shaped protrusion 7 protruding radially outward from the cylindrical outer peripheral surface 6 of the inner cylinder body 5 It has a resin-made inner cylinder 8 and a recess 9 that receives the protrusion 7 of the inner cylinder 8 and is recessed in the radially outward direction, defines the recess 9 and contacts the outer surface 10 of the protrusion 7. And an outer cylinder 13 made of synthetic resin having a recess surface 11 on the inner peripheral surface 12, and the outer cylinder 13 supports the inner cylinder 8 rotatably on the inner peripheral surface 12 in the R direction, The cylindrical outer peripheral surface 14 is fitted and fixed to the inner peripheral surface 16 of the housing 15 so as not to rotate in the R direction.

  The protrusion 7 is formed integrally with the outer peripheral surface 6 of the inner cylinder main body 5 and has an annular protrusion 21 having a trapezoidal cross section. The protrusion 21 is a pair of truncated cones. The outer surface 10 of the protrusion 7 is provided with a surface 22 and a cylindrical surface 23 sandwiched between a pair of frustoconical surfaces 22 in the A direction which is the axial direction and having a center concentric with the axis O. A pair of frustoconical surfaces 22 and a cylindrical surface 23 are included.

  The recess 9 that has received the protrusion 21 has an annular recess 25 having a shape complementary to the protrusion 21.

  The outer cylinder 13 is divided into two parts in the A direction, and includes one divided body 31 and the other divided body 32.

  The divided body 31 is connected to a large-diameter cylindrical portion 37 having a large-diameter cylindrical outer peripheral surface 35 and a cylindrical inner peripheral surface 36, a small-diameter cylindrical outer peripheral surface 38, and the inner peripheral surface 36 in the A direction. A small-diameter cylindrical portion 41 having a frustoconical inner peripheral surface 39 and a cylindrical inner peripheral surface 40 connected to the inner peripheral surface 39 in the A direction and having a larger diameter than the inner peripheral surface 36, and a cylinder An annular large-diameter flange 42 provided on the outer peripheral surface 35 of the portion 37, an annular small-diameter flange 43 provided on the outer peripheral surface 38 of the cylindrical portion 41, and an outer peripheral surface 35 of the cylindrical portion 37. And a protrusion 45 provided on one end surface 44 in the A direction of the flange portion 42, and the inner peripheral surface 36 of the cylindrical portion 37 is formed on the outer peripheral surface 6 of the inner cylinder main body 5 with an R The cylindrical portion 41 and the flange portion 43 serving as the dividing surfaces are in contact with each other so as to be freely rotatable in the direction A. 7 are formed an annular recess 48 between the cylindrical portion 37 and the flange 43 in the A direction is formed.

  The projecting portion 45 opens into the end surface 49 of the housing 15 and is fitted into a notch 50 formed in the inner peripheral surface 16 of the housing 15, and is divided by fitting the projecting portion 45 into the notch 50. The body 31, and thus the outer cylinder 13, does not rotate in the R direction with respect to the housing 15.

  The divided body 32 formed in the same manner as the divided body 31 except for the flange 42, the protrusion 45, the recess 47, and the annular protrusion 55 fitted in the recess 47 has a large-diameter cylindrical outer periphery. A large-diameter cylindrical portion 58 having a surface 56 and a cylindrical inner peripheral surface 57, a small-diameter cylindrical outer peripheral surface 59, and a frustoconical inner peripheral surface 60 and A connected to the inner peripheral surface 57 in the A direction. A small diameter cylindrical portion 62 having a cylindrical inner peripheral surface 61 connected to the inner peripheral surface 60 in the direction and having a larger diameter than the inner peripheral surface 57, and a circle provided on the outer peripheral surface 59 of the small diameter cylindrical portion 62. An annular flange 63 is integrated with a small-diameter cylindrical portion 62 serving as a split surface and an annular projection 55 provided on one end surface 64 in the A direction of the flange 63 and fitted in the recess 47. The inner peripheral surface 57 of the cylindrical portion 58 is freely rotatable in the R direction on the outer peripheral surface 6 of the inner cylinder main body 5. Contact and the end face 64 is in contact with the end face 46, the recess 65 of the annular between the cylindrical portion 58 and the small diameter flange portion 63 in the A direction is formed.

  The recess surface 11 that defines the recess 9 composed of the recess 25 having a shape complementary to the outer surface shape of the protrusion 21 includes an inner peripheral surface 39, an inner peripheral surface 40, an inner peripheral surface 60, and an inner peripheral surface. The rotary friction damper 1 is rotated in the R direction on the inner peripheral surface 16 of the housing 15 by the outer peripheral surface 14 of the outer cylinder 13 composed of the outer peripheral surface 35 of the cylindrical portion 37 and the outer peripheral surface 56 of the cylindrical portion 58. It is designed to be fitted and fixed so that it does not.

  Connecting means for connecting the divided body 31 and the divided body 32 having the flanges 43 and 63 on the side of the end faces 46 and 64, which are the divided surface side, by bringing them into contact with each other at the end faces 46 and 64 facing each other. Reference numeral 71 includes a ring body 72 that can be expanded in diameter and elastically holds both flange portions 43 and 63.

  The annular body 72 having the butt end faces 73 and 74 is provided on both edges of the plate-like annular part 75 and the plate-like annular part 75 surrounding the outer peripheral surfaces of both flange parts 43 and 63. A pair of plate-like leg portions 76 that are disposed in the recesses 48 and 65 and elastically sandwich the flange portions 43 and 63 are integrally provided.

  In the rotary friction damper 1 described above, the inner cylinder 8 is also rotated in the R direction by the rotation of the rotating shaft 3 in the R direction, and the recess of the outer cylinder 13 fixed to the housing 15 by the rotation of the inner cylinder 8 in the R direction. Sliding friction occurs between the inner peripheral surface 12 having the surface 11 and the outer peripheral surface 6 of the inner cylinder main body 5 of the inner cylinder 8 and the outer surface 10 composed of the pair of frustoconical surfaces 22 and the cylindrical surface 23 of the projections 7. This sliding friction causes attenuation in the rotation of the rotating shaft 3 in the R direction. Since the rotary friction damper 1 includes the outer surface 10 of the protruding portion 21 protruding in the radial direction and the recessed surface 11 that contacts the outer surface 10 of the protruding portion 21, the sliding friction surface can be increased. A relatively large frictional force that causes attenuation in rotation in the R direction of the rotating shaft 3 can be stably obtained, and thus downsizing can be achieved.

  In the rotary friction damper 1 described above, the outer cylinder 13 divided into two in the A direction was used, but instead, the outer cylinder 13 was divided into two in the R direction as shown in FIGS. The outer cylinder 81 may be used, and in the outer cylinder 81 including the two divided bodies 82 and 83 made of synthetic resin, the divided bodies 82 and 83 are two sets of divided surfaces 86 that form gaps 84 and 85. And 87 are faced to each other and close to each other, and are connected to each other by connecting means 88.

  The rotary friction damper 1 shown in FIG. 5 to FIG. 8 is also provided with an inner cylinder main body 92 and an inner cylinder fixed to the cylindrical outer peripheral surface 4 of the rotary shaft 3 by the cylindrical inner peripheral surface 91 so as not to rotate in the R direction. A synthetic resin inner cylinder 95 having an annular protrusion 7 projecting radially outward from a cylindrical outer peripheral surface 93 of the main body 92, and receiving the protrusion 7 of the inner cylinder 95 and being recessed radially outward. And a synthetic resin outer cylinder 81 having a concave surface 98 which defines the concave portion 96 and contacts the outer surface 97 of the projection 7 on the inner peripheral surface 99. The outer cylinder 81 is fitted and fixed on the inner peripheral surface 99 so that the inner cylinder 95 is rotatably supported in the R direction, while the outer peripheral surface 100 is not rotated in the R direction on the inner peripheral surface 16 of the housing 15. It has become so.

  5 to 8, the protrusion 7 is formed integrally with the outer peripheral surface 93 of the inner cylinder main body 92 and has an annular protrusion 111 having a trapezoidal cross section. Like the protrusion 21, it includes a pair of frustoconical surfaces 112 and a cylindrical surface 113 sandwiched between the pair of frustoconical surfaces 112 in the A direction and having a center concentric with the axis O. The outer surface 97 of the protrusion 7 formed of the protrusion 111 that is wedge-shaped more than the protrusion 21 includes the pair of frustoconical surfaces 112 and the cylindrical surface 113.

  The recess 96 that receives the protrusion 111 also has an annular recess 114 having a shape complementary to the protrusion 111.

  The divided body 82 includes a semi-cylindrical portion 117 having a semi-cylindrical outer peripheral surface 115 and a semi-cylindrical inner peripheral surface 116, and a semi-annular flange portion 118 provided on the outer peripheral surface 115 of the semi-cylindrical portion 117. , And an outer peripheral surface 115 of the semi-cylindrical portion 117, and a protrusion 120 provided on one end surface 119 of the flange portion 118 in the A direction, and the semi-cylindrical portion 117 is formed on the outer peripheral surface 115. A semi-cylinder that extends in the R direction and has two semicircular grooves 125 arranged away from each other in the A direction, and is in contact with the outer peripheral surface 93 of the inner cylinder main body 92 so as to be rotatable in the R direction. The inner peripheral surface 116 of the portion 117 defines a semicircular recess 126 that receives the protrusion 7 of the inner cylinder 95 formed of the protrusion 111 and is formed on the pair of frustoconical surfaces 112 and the cylindrical surface 113 of the protrusion 111. It has a semi-annular recess surface 127 in contact with the recess surface Reference numeral 27 denotes a semicircular conical inner peripheral surface 128 and an inner peripheral surface 128 sandwiched between the inner peripheral surface 128 and connected to the inner peripheral surface 128, and a semicylindrical inner peripheral surface 129 having a larger diameter than the inner peripheral surface 116. have.

  The protrusion 120 is fitted into a notch 50 that is opened in the end surface 49 of the housing 15 and formed in the inner peripheral surface 16 of the housing 15, and is divided by fitting the protrusion 120 into the notch 50. The body 82 extends so that the outer cylinder 81 does not rotate in the R direction with respect to the housing 15.

  A divided body 83 formed in the same manner as the divided body 82 is provided on a semi-cylindrical portion 137 having a semi-cylindrical outer peripheral surface 135 and a semi-cylindrical inner peripheral surface 136, and an outer peripheral surface 135 of the semi-cylindrical portion 137. A semicircular collar 138 and a protrusion 140 provided on one end surface 139 of the collar 138 in the A direction on the outer peripheral surface 135 of the semicylindrical part 137, The cylindrical portion 137 has two semicircular grooves 145 extending in the R direction on the outer peripheral surface 135 and arranged away from the A direction, and is formed in the R direction on the outer peripheral surface 93 of the inner cylinder main body 92. The inner circumferential surface 136 of the semi-cylindrical portion 137 that is in contact with the rotation defines a semi-annular recess 146 that receives the projection 7 of the inner cylinder 95 made of the projection 111 and a pair of flanges of the projection 111. A semi-annular recess that contacts the conical surface 112 and the cylindrical surface 113 147, and the recess surface 147 is connected to the inner peripheral surface 148 by being sandwiched between the pair of semi-conical inner peripheral surface 148 and the inner peripheral surface 148, and is larger than the inner peripheral surface 136. It has a semi-cylindrical inner peripheral surface 149 having a diameter.

  The projecting portion 140 opens into the end surface 49 of the housing 15 and is fitted into another notch 150 formed on the inner peripheral surface 16 of the housing 15, and the projecting portion 140 is fitted into the notch 150. The split body 83 extends so that the outer cylinder 13 does not rotate in the R direction with respect to the housing 15.

  The connection means 88 shown in FIGS. 5 to 8 includes elastic annular bodies 155 and 156 made of O-rings extending in the R direction through the respective grooves 125 and 145 of the semi-cylindrical portions 117 and 137. The annular bodies 155 and 156 elastically tighten the outer cylinder 81 so as to reduce the diameter of the outer cylinder 81 composed of the semi-cylindrical portions 117 and 137, while being pressed by the inner peripheral surface 16 of the housing 15. It is in elastic contact with the surface 16.

  Thus, in the outer cylinder 81 provided with the divided body 82 and the divided body 83, the recess 96 includes the recess 114, and the recess 114 includes the recess 126 and the recess 146. 98 includes a recess surface 127 and a recess surface 147, an inner peripheral surface 99 includes an inner peripheral surface 116 and an inner peripheral surface 136, and the outer peripheral surface 100 includes an outer peripheral surface 115 and an outer peripheral surface. It consists of 135.

  Also in the rotary friction damper 1 shown in FIGS. 5 to 8, the inner cylinder 95 is also rotated in the R direction by the rotation of the rotating shaft 3 in the R direction, and the outer cylinder fixed to the housing 15 is rotated by the rotation of the inner cylinder 95 in the R direction. Sliding friction is generated between the inner peripheral surface 99 having the recessed surface 98 of the cylinder 81, the outer peripheral surface 93 of the inner cylinder 95, and the outer surface 97 including the pair of frustoconical surfaces 112 and the cylindrical surface 113, and this sliding friction. Accordingly, the rotation of the rotating shaft 3 in the R direction is attenuated. The rotary friction damper 1 includes the outer surface 97 of the protrusion 7 projecting radially outward and the concave surface 98 that contacts the outer surface 97 of the protrusion 7 and is recessed radially outward. The sliding friction surface can be enlarged, and a relatively large frictional force that causes the rotation of the rotating shaft 3 to attenuate in the R direction can be obtained stably. Since the bodies 155 and 156 elastically tighten the outer cylinder 81 so as to reduce the diameter of the outer cylinder 81 composed of the semi-cylindrical portions 117 and 137, a sliding friction surface can be secured stably.

  The rotary friction damper 1 includes the protrusions 7 each having one annular protrusion 21 or 111. Instead of such protrusions 7, as shown in FIGS. A protrusion 7 having a spiral protrusion 171 may be provided. In this case, the recess 9 has a spiral recess 172 that receives the spiral protrusion 171, and the inner periphery of the outer cylinder 13. The surface 12 is movable in the A direction with respect to the outer peripheral surface 14.

  That is, the rotary friction damper 1 shown in FIGS. 9 to 17 includes an inner cylinder main body 5 that is fixed to the cylindrical outer peripheral surface 4 of the rotary shaft 3 by the cylindrical inner peripheral surface 2 so as not to rotate in the R direction. An inner cylinder 8 made of synthetic resin having a spiral protrusion 171 made of a male screw protruding radially outward from the cylindrical outer peripheral surface 6 of the inner cylinder main body 5 and the spiral protrusion 171 of the inner cylinder 8 are received. And has a helical recess 172 made of a female screw that is screwed into the helical protrusion 171 and recessed radially outward, and defines the helical recess 172 and has a male screw surface of the helical protrusion 171. And an outer cylinder 13 made of a synthetic resin having a concave surface 11 made of an internally threaded surface in contact with the outer surface 10 made of the inner peripheral surface 12.

  The outer cylinder 13 has a recess surface 11 and is made of a synthetic resin on the inner diameter side that rotatably supports the inner cylinder 8 in the R direction by screwing the spiral protrusion 171 and the spiral recess 172 on the recess surface 11. The cylindrical body 175 has a cylindrical inner peripheral surface 177 that is slidably contacted in the direction A with the outer peripheral surface 176 of the cylindrical body 175 and is fitted to the inner peripheral surface 16 of the housing 15 so as not to rotate in the R direction. And a cylindrical body 178 made of a synthetic resin on the outer diameter side having an outer peripheral surface 14 to be fixed.

  The cylindrical body 175 extends in the A direction from one end face 181 and extends in the A direction from the three slits 182 and the other end face 183 arranged at equal central angular intervals of 120 ° in the R direction. The cylinder body 185 having three slits 184 arranged at equal central angle intervals of 120 ° in the direction, and the inner circumference that is also the inner circumferential surface of the cylinder body 185 divided in the R direction by the slits 182 and 184 An end surface having a recess surface 11 formed of a female thread surface formed on the surface 12 and an outer peripheral surface 186 that is also an outer peripheral surface 176 that is also an outer peripheral surface of the cylindrical body 185 divided in the R direction by slits 182 and 184 An engaging projection 187 projecting in the A direction from 183 and an inner peripheral surface 12 of the cylindrical body 185 and at one end to a slit 184 An air vent groove 188 opened at the end surface 181 at the other end, and an air vent groove 189 formed on the inner peripheral surface 12 of the cylindrical body 185 and opened at the slit 182 at one end and opened at the end surface 183 at the other end. It has.

  The slit 182 is in front of the end surface 183 and extends in the A direction to the air vent groove 189, and the slit 184 that is separated from the slit 182 with a central angle of 60 ° in the R direction is in front of the end surface 181. The air vent groove 188 extends in the A direction.

  The cylindrical body 178 includes a cylindrical main body 191 having a cylindrical inner peripheral surface 177 and an outer peripheral surface 14, an annular flange 42 provided on the outer peripheral surface 14 of the cylindrical main body 191, and the cylindrical main body 191. A protrusion 45 provided on one end face 44 in the A direction of the flange 42 on the outer peripheral surface 14 and the engagement protrusion 187 in the R direction is sandwiched between the protrusion 45 and the notch 50 of the housing 15. And a pair of locking projections 192 that are provided on the inner peripheral surface 177 of the cylindrical body 191 and are movably in contact with the engagement projections 187 in the A direction.

  The cylindrical body 175 is prevented from rotating in the R direction with respect to the cylindrical body 178 by fitting and engaging between the pair of engaging projections 192 of the engaging protrusion 187. By fitting the protrusion 45 into the notch 50, the protrusion 45 is prevented from rotating in the R direction with respect to the housing 15.

  In the rotary friction damper 1 shown in FIGS. 9 to 17, the inner cylinder 8 is also rotated in the R direction by the rotation of the rotating shaft 3 in the R direction, and the helical protrusion of the inner cylinder 8 is rotated by the rotation of the inner cylinder 8 in the R direction. The cylindrical body 175 is moved in the A direction with respect to the inner cylinder 8 and the cylindrical body 178 through screwing between the portion 171 and the helical recess 172 of the cylindrical body 185. In this movement, the male thread surface of the helical projection 171 Between the outer surface 10 and the recessed surface 11 formed of the female thread surface defining the spiral recess 172, between the outer peripheral surface 176 of the cylindrical body 185 and the inner peripheral surface 177 of the cylindrical main body 191, Sliding friction between the outer peripheral surface 186 of 187 and the inner peripheral surface 177 of the cylindrical body 191, between both side surfaces in the R direction of the engaging projections 187 and both side surfaces in the R direction of the pair of locking projections 192 Is generated, and this sliding friction attenuates the rotation of the rotating shaft 3 in the R direction. In the rotary friction damper 1, a sliding surface between the outer surface 10 and the recess surface 11, a sliding surface between the outer peripheral surface 176 and the inner peripheral surface 177, and between the outer peripheral surface 186 and the inner peripheral surface 177. Since the sliding surface and many friction sliding surfaces including the sliding surface between the engaging projection 187 and the locking projection 192 are provided, the sliding friction surface can be enlarged so that the R direction of the rotary shaft 3 can be increased. A relatively large frictional force that causes attenuation in the rotation of the motor can be stably obtained, and thus downsizing can be achieved.

  In the rotary friction damper 1 shown in FIGS. 9 to 17, the recess surface 11 formed of the female thread surface of the cylinder body 185 having the slits 182 and 184 is provided with the elastic interference of the cylinder body 185 made of synthetic resin. In addition to this, as shown in FIGS. 18 and 19, the cylinder body 185 has an elastic margin of an elastic ring body 201 made of an O-ring. May be screwed into the spiral protrusion 171 of the inner cylinder 8. That is, in FIG. 18 and FIG. 19, the cylinder body 185 having the slits 182 and 184 in the cylinder 175 is divided in the R direction by the slits 182 and 184 and extends to the outer peripheral surface 176 in the R direction. It has two annular grooves 202 that are arranged apart from each other in the direction, and is elastically reduced in diameter by an elastic annular body 201 attached to the annular groove 202.

  In the rotary friction damper 1 shown in FIGS. 18 and 19, the concave surface 11 formed by the female thread surface of the cylindrical body 185 is formed by the elastic force of the elastic annular body 201 in addition to the elastic force of the synthetic resin of the cylindrical body 185 itself. As a result of being able to be screwed into the helical protrusion 171 of the inner cylinder 8 with a tightening margin, the outer surface 10 made of a male screw surface of the helical protrusion 171 and the concave surface 11 made of a female screw surface defining the helical recess 172, The frictional resistance on the sliding friction surface between the two can be increased, and thus a relatively large frictional force that causes the rotation of the rotating shaft 3 in the R direction can be stably obtained, and the size can be further reduced. Can do.

  When such an elastic annular body 201 is used, as shown in FIGS. 18 and 19, the elastic annular body 201 has an outer peripheral surface 205 in elastic contact with the inner peripheral surface 177 of the cylindrical body 191 so as to be slidable in the A direction. As shown in FIG. 20, the outer peripheral surface 205 is mounted in the annular groove 202 so that the outer peripheral surface 205 is not in contact with the inner peripheral surface 177 of the cylindrical body 191. In the former case, the friction on the friction surface between the outer peripheral surface 205 of the elastic annular body 201 and the inner peripheral surface 177 of the cylindrical body 191 can be used by the rotation of the rotating shaft 3 in the R direction. A relatively large frictional force that causes attenuation in the rotation of the rotating shaft 3 in the R direction can be stably obtained, and further downsizing can be achieved.

DESCRIPTION OF SYMBOLS 1 Rotary friction damper 2, 12 Inner peripheral surface 3 Rotating shaft 4 Outer peripheral surface
DESCRIPTION OF SYMBOLS 5 Inner cylinder main body 7 Protrusion 8 Inner cylinder 9 Recess 10 Outer surface 11 Recessed surface 13 Outer cylinder 14 Outer surface 15 Housing 16 Inner surface

Claims (12)

  A radially projecting projection and a synthetic resin inner cylinder that has one of the recesses that receive the projection and that are recessed in the radial direction and are fixed to the rotating shaft, and a radially projecting projection and the projection And has a synthetic resin outer cylinder fixed to the housing, while having the other of the recesses radially recessed and rotatably supporting the inner cylinder. A rotary friction damper that is in contact with the recess surface that defines the recess on the outer surface.   The protrusion has at least one annular protrusion having a trapezoidal cross section, and the recess has an annular recess having a shape complementary to the protrusion. Item 2. The rotary friction damper according to Item 1.   The outer cylinder is divided into two parts in the axial direction. In the outer cylinder that is divided into two parts and consists of one divided body in the axial direction and the other divided body in the axial direction, the one divided body and the other The rotary friction damper according to claim 1 or 2, wherein the divided bodies are opposed to each other at their divided surfaces and are connected to each other by a connecting means.   Each division body has a collar part in the division | segmentation surface side, The connection means is equipped with the ring body which can be expanded freely which elastically holds both collar parts. Rotary friction damper.   The outer cylinder is divided into at least two in the circumferential direction. In the outer cylinder that is divided into at least two and includes one divided body and the other divided body, the one divided body and the other divided body The rotary friction damper according to claim 1 or 2, wherein the rotary friction dampers face each other at their divided surfaces and are connected to each other by a connecting means.   Each divided body has a semi-cylindrical portion having at least one groove extending in the circumferential direction on the outer peripheral surface, and the connecting means is an elastic ring extending in the circumferential direction through each groove of the semi-cylindrical portion. The rotary friction damper according to claim 5, comprising a body.   The protrusion has a spiral protrusion, the recess has a spiral recess that receives the spiral protrusion, and the inner peripheral surface of the outer cylinder is axially directed to the outer peripheral surface. The rotary friction damper according to claim 1, which is movable.   The outer cylinder has a cylindrical tube made of synthetic resin on the inner diameter side that rotatably supports the inner cylinder on the inner peripheral surface, and an inner peripheral surface that is slidably in contact with the outer peripheral surface of the cylindrical body at least in the axial direction. The rotary friction damper according to claim 7, comprising a cylindrical body made of synthetic resin on the outer diameter side having an outer peripheral surface fixed to the housing.   The rotary friction damper according to claim 8, wherein the cylindrical body on the inner diameter side has at least one slit extending in the axial direction from one end face.   The cylinder on the inner diameter side has at least one annular groove extending in the circumferential direction on the outer peripheral surface, and is elastically reduced in diameter by an elastic annular body mounted in the annular groove. The rotary friction damper according to claim 9.   11. The rotary type according to claim 10, wherein the elastic annular body is mounted in an annular groove of the inner diameter side cylindrical body so as to elastically contact the inner peripheral surface of the outer diameter side cylindrical body so as to be slidable in the axial direction. Friction damper.   The rotary friction damper according to claim 10, wherein the elastic annular body is mounted in an annular groove of the inner diameter side cylinder so as not to contact the inner peripheral surface of the outer diameter side cylinder.

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