JP2010216528A - Rotary damper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary damper which can obtain braking changeless at high temperature or low temperature without temperature dependence in generating braking, and is suitable for using to vehicle seat for automobile. <P>SOLUTION: A rotary damper 1 is equipped with: a housing body 3 with an inner peripheral surface 2; a rotor 7 which is rotatably arranged with respect to the housing body 3 within the housing body 3 so that a space 6, housing a viscous fluid 5 between the inner peripheral surface 2 and outer peripheral surface 4, may be formed; and vane means 8 which generates high flow resistance in the viscous fluid 5 in an R1 directional rotation of the rotor 7 with respect to the housing body 3, and generates lower flow resistance than the flow resistance in an R2 directional rotation of the rotor 7 with respect to the housing body 3, respectively. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rotary damper in which a rotating body is rotatably accommodated inside a container that contains a viscous fluid, and braking is applied to the relative rotation of the rotating body with respect to the container by the viscous fluid.

  A one-way rotary damper of this type that gives a large brake to one rotation of the rotating body and a small brake to the other rotation of the rotating body by the viscous fluid passing through the gap. It is known from Patent Document 1 and the like.

JP 2005-188636 A JP-A-9-42350 JP 9-329173 A JP-A-8-109940 JP-A-8-296687

  By the way, in such a rotary damper, since the viscosity of the viscous fluid changes depending on the temperature, the braking is reduced when used at a high temperature, while the braking is increased when used at a low temperature, and there is no change at a high temperature or a low temperature. The use of this type of rotary damper for a vehicle seat for which braking is required, for example, a vehicle seat such as an automobile in which a backrest portion is foldable is not suitable.

  The present invention has been made in view of the above-described points, and the object of the present invention is to provide a brake that does not depend on the temperature of generated braking and that does not change at high or low temperatures. Another object of the present invention is to provide a rotary damper suitable for use in a vehicle seat.

  The rotary damper according to the present invention increases the temperature between a container having a cylindrical inner peripheral surface, and the cylindrical inner peripheral surface of the container and the cylindrical outer peripheral surface concentric with the inner peripheral surface. A rotating body disposed in the housing body so as to be relatively rotatable with respect to the housing body so as to form a space for accommodating the viscous fluid whose viscosity is lowered, and in one direction of the rotating body with respect to the housing body In relative rotation, the flow resistance of the viscous fluid is large, and in the relative rotation in the other direction, which is opposite to the relative rotation in one direction of the rotating body with respect to the container, the flow resistance is smaller than the flow resistance. In order to generate each of the above, a vane means disposed in a space for accommodating a viscous fluid between the cylindrical inner peripheral surface of the container and the cylindrical outer peripheral surface of the rotating body, The cylindrical inner peripheral surface of the container and the cylindrical outer peripheral surface of the rotating body A pair of elastic vanes that divide the space containing the viscous fluid into two chambers, and another elastic vane that further divides at least one of the two chambers divided by the pair of elastic vanes into two chambers. Each of the pair of elastic vanes has a curved shape that is connected to the outer peripheral surface of the rotating body at one end and is convex in a direction opposite to the relative rotation in one direction of the rotating body with respect to the container. Corresponding to the convex surface and a curved concave surface connected to the outer peripheral surface of the rotating body at one end and extending along the convex surface. The convex surface is accommodated on the other end side. A pair of wedge spaces facing each other in the rotational direction of the relative rotation of the rotating body with respect to the body are arcuate convex surfaces that form between the inner peripheral surface of the container and the arcuate convex surface is a rotating body with respect to the container In the direction of relative rotation of The width in the radial direction of one wedge space communicating with one of the two adjacent chambers with the arc-shaped convex surface in between is the space between the arc-shaped convex surface in the rotational direction of the relative rotation of the rotating body with respect to the container. The radial width of the one wedge space is determined so as to gradually become narrower toward the other wedge space communicating with the other of the two adjacent chambers, and the rotating body with respect to the container In the rotational direction of the relative rotation of the rotating body, the radial width of the other wedge space communicating with the other of the two adjacent chambers with the arcuate convex surface in between is the rotational rotation of the rotating body relative to the container The width of the other wedge space in the radial direction is gradually narrowed toward the one wedge space communicating with one of the two adjacent chambers with the arcuate convex surface therebetween. Viscous fluid passing through a pair of wedge spaces Each of the pair of elastic vanes is elastically deflected, and the radial width of the pair of wedge spaces is determined by the viscosity thereof.

  According to the rotary damper of the present invention, in two chambers that are divided by the pair of elastic vanes and adjacent in the rotational direction of the relative rotation of the rotating body with respect to the housing body, One chamber located on the relative rotation side in the other direction opposite to the relative rotation is expanded and the other chamber on the relative rotation side in one direction of the rotation body with respect to the storage body is reduced with respect to the storage body. When the rotating body is rotated, the pressure of the viscous fluid is applied to the concave surfaces of the pair of elastic vanes, so that the other end sides of the pair of elastic vanes approach the inner peripheral surface of the container. As a result of elastic deformation of each of the pair of elastic vanes so as to reduce the pair of wedge spaces, the viscous fluid flows from the other chamber to the one chamber through the pair of reduced wedge spaces, and this reduced size is reduced. A pair of wedge spaces A large amount of braking by the excess viscous fluid is given to the rotation of the rotating body, while when the rotating body is rotated relative to the container so as to reduce one chamber and expand the other chamber, a pair of elastic Since viscous fluid pressure is applied to each curved convex surface of the vane, a pair of elastic members are formed so that the other end side of each of the pair of elastic vanes is separated from the inner peripheral surface of the container to expand the pair of wedge spaces. As a result of each of the vanes being elastically deformed, the viscous fluid flows from the other chamber to the other chamber through the pair of expanded wedge spaces, and is caused by the viscous fluid passing through the pair of expanded wedge spaces. A small amount of braking is applied to the rotation of the rotating body to act as a one-way damper.

  According to the rotary damper according to the present invention, since the viscous fluid whose viscosity decreases as the temperature rises passes through the pair of wedge spaces in the rotation of the rotating body, for example, at a lower temperature than normal temperature (20 ° C.). When the viscous fluid having increased viscosity passes through the pair of wedge spaces, the other end side of each of the pair of elastic vanes is separated from the inner peripheral surface of the container due to an increase in the pressure of the viscous fluid in the pair of wedge spaces. As a result, the pair of elastic vanes are elastically deformed to widen the pair of wedge spaces. As a result, the viscosity of the viscous fluid itself increases and the fluid flow resistance decreases due to the expansion of the pair of wedge spaces. In the case where the viscous fluid having a viscosity lower than that at room temperature passes through the pair of wedge spaces at a high temperature, the pressure of the viscous fluid in the pair of wedge spaces reduces the pressure of each of the pair of elastic vanes. The other end of As a result of each of the pair of elastic vanes being elastically deformed so as to approach the inner peripheral surface of the container and the pair of wedge spaces are narrowed, the viscosity of the viscous fluid itself is reduced and the fluid flow resistance is increased by the reduction of the pair of wedge spaces. In addition, braking at normal temperature can be maintained regardless of high temperature, and thus braking generated does not depend on temperature, and braking that does not change at both high and low temperatures can be obtained.

  In a preferred example, the concave surface extends along the convex surface so as to gradually approach the convex surface from one end to the other end of the convex surface, and the arc-shaped convex surface has a curvature radius smaller than the curvature radius of the inner peripheral surface of the container. Have.

  In a preferred example of the rotary damper according to the present invention, the other elastic vanes include a base portion formed integrally with the inner peripheral surface of the container, and a base portion formed integrally with the base portion and facing the outer peripheral surface of the rotating body. And an elastically flexible tongue having an arcuate surface.

  Also in each of such other elastic vanes, the tongue portion has an arcuate concave surface that forms a pair of wedge spaces facing each other in the rotation direction of the relative rotation of the rotating body with respect to the container, and the outer peripheral surface of the rotating body. The arcuate concave surface may have one wedge communicated with one of the two adjacent chambers with the arcuate concave surface in the rotation direction of the relative rotation of the rotating body with respect to the container. The radial width of the one wedge space is determined so that the radial width of the space gradually decreases toward the other wedge space communicating with the other of the two adjacent chambers. And the width in the radial direction of the other wedge space communicating with the other one of the two adjacent chambers gradually increases toward the one wedge space communicating with one of the two adjacent chambers. To determine the width of the other wedge space in the radial direction. Cage, the viscous fluid passing through the pair of wedge spaces may be adapted to determine the width in the radial direction of the pair of wedge spaces by its viscosity by bending the respective other elastic vanes resiliently.

  As the viscous fluid according to the present invention, silicone oil can be cited as a preferred example, but other viscous fluids may be used, and the container may be made of metal, but it is light in weight and cost. It may be made of a hard synthetic resin for reasons such as reduction of the rotation, and the rotating body may also be made of metal, but may be made of a hard synthetic resin for reasons such as weight reduction and cost reduction. The pair of elastic vanes may be separated from the rotating body and fixed to the rotating body by welding, fitting, adhesion, or the like, but preferably formed integrally with the rotating body. In the case where the elastic vanes are integrally formed, it is preferable that the rotating body is made of a synthetic resin material that imparts appropriate elasticity to each of the pair of elastic vanes. Separately welded, fitted and bonded to the container However, when the container and the other elastic vane are integrally formed, the container is elastic enough to each of the other elastic vanes. It is preferable to use a synthetic resin material to which is given.

  ADVANTAGE OF THE INVENTION According to this invention, the generated braking does not depend on temperature, can obtain the braking which does not change at high temperature and low temperature, and can provide a rotary damper suitable for use in vehicle seats for automobiles and the like. .

It is II sectional view explanatory drawing of FIG. 2 of a preferable example of this invention. It is II-II sectional view explanatory drawing of the example shown in FIG. 4 of FIG. FIG. 5 is a cross-sectional explanatory view taken along the line III-III in FIG. 4 of the example shown in FIG. 1. It is a front view of the example shown in FIG. It is a rear view of the example shown in FIG. It is a perspective view of the example shown in FIG. It is a partially expanded explanatory view of the example shown in FIG. It is explanatory drawing which attached the rotating shaft to the example shown in FIG. It is a perspective view of the rotating shaft shown in FIG. It is explanatory drawing of the example with which the example shown in FIG. 1 was mounted | worn with the vehicle seat. It is operation | movement explanatory drawing of the example shown in FIG. It is operation | movement explanatory drawing of the example shown in FIG.

  Next, embodiments of the present invention will be described in more detail based on preferred examples shown in the drawings. The present invention is not limited to these examples.

  1 to 7, the rotary damper 1 of this example includes a synthetic resin container 3 having a cylindrical inner peripheral surface 2, and an inner peripheral surface 2 and the inner peripheral surface 2 that are concentric with respect to an axis O. Between the cylindrical outer peripheral surface 4 and the container 3 with respect to the container 3 so as to form a space 6 for containing the viscous fluid 5 made of silicone oil or the like whose viscosity decreases with increasing temperature. And the relative rotation of the rotating body 7 in one direction relative to the housing 3 with respect to the containing body 3, in the present example. In the rotation of the rotating body 7 in the R1 direction with respect to the container 3, a large flow resistance is exerted on the viscous fluid 5, and the relative rotation in the opposite direction to the relative rotation in one direction of the rotating body 7 with respect to the container 3 is relative. In the rotation, in this example, in the rotation of the rotating body 7 with respect to the container 3 in the R2 direction, To cause each small flow resistance than the flow resistance, and a vane means 8 disposed in the space 6.

  The container 3 is integrally formed radially inward with a cylindrical portion 15 having a cylindrical inner peripheral surface 2 and one annular end portion 16 in the A direction that is the axial direction of the cylindrical portion 15. And a lid member 19 that has an inner peripheral surface 18 that defines the through-hole 17 and is fixed to the other annular end portion 20 in the A direction of the cylindrical portion 15 by a plurality of screws 21. 22.

  The flange portion 19 defines one side in the A direction of the space 6 with one side surface 25 in the A direction, and the lid body 22 has a through hole 26 at the center and through holes 27 and 28 at both ends. And an elliptical plate-like portion 30 that defines the other side of the space 6 in the A-direction with one side surface 29 in the A-direction, and a cylindrical protrusion integrally formed on the one side surface 29 of the plate-like portion 30 31.

  The hollow rotating body 7 has an inner peripheral surface 34 of the plate-like portion 30 that defines the inner peripheral surface 18 and the through hole 26 of the flange portion 19 of the container 3 with annular end portions 32 and 33 in the axial direction A. The inner peripheral surface 36 that defines the hollow portion 35 of the rotating body 7 has irregularities (serrations) 37.

  Between the inner peripheral surface 18 of the flange portion 19 and the end portion 32 of the rotating body 7 in the axial direction A, between the end portion 20 of the cylindrical portion 15 and the protrusion 31 fitted to the end portion 20 and the plate A seal ring 38 for preventing the viscous fluid 5 from leaking from the space 6 to the outside of the container 3 is disposed between the inner peripheral surface 34 of the shaped portion 30 and the end portion 33 in the axial direction A of the rotating body 7. Has been.

  The vane means 8 is disposed inside the container 3 for containing the viscous fluid 5 between the cylindrical inner peripheral surface 2 of the container 3 and the cylindrical outer peripheral surface 4 of the rotating body 7 concentric with the inner peripheral surface 2. A pair of elastic vanes 43 and 44 that divide the annular space 6 into two chambers 41 and 42, and at least one of the two chambers 41 and 42 partitioned by the pair of elastic vanes 43 and 44, in this example Each of the two chambers 41 and 42 is further provided with a pair of elastic vanes 49 and 50 as other elastic vanes for dividing the two chambers 41 and 42 into two chambers 45 and 46 and 47 and 48.

  In the elastic vanes 43 and 44 and 49 and 50, the elastic vane 43 and the elastic vane 44, and the elastic vane 49 and the elastic vane 50 are formed in the same manner with a symmetrical shape with respect to the axis O. The elastic vane 43 and the elastic vane 49 will be described in detail, and the elastic vane 44 and the elastic vane 50 will be described and illustrated with the same reference numerals as the elastic vane 43 and the elastic vane 49.

  The elastic vane 43 that divides the chamber 46 and the chamber 47 is connected to the outer peripheral surface 4 of the rotating body 7 at one end, and has a curved convex surface 61 that is convex toward the R2 direction of the rotating body 7 with respect to the container 3. In correspondence with the convex surface 61, the one end portion is connected to the outer peripheral surface 4 of the rotating body 7 and extends along the convex surface 61 so as to gradually approach the convex surface 61 from one end portion to the other end portion of the convex surface 61. And a curved concave surface 62 that terminates together with the terminal end of the curved surface.

  The convex surface 61 has a pair of wedge spaces 63 and 64 facing each other in the R1 and R2 directions which are also the rotation direction R of the relative rotation of the rotating body 7 with respect to the container 3 on the other end side. And an arcuate convex surface 65 having a radius of curvature smaller than the radius of curvature of the inner peripheral surface 2, and the arcuate convex surface 65 of the one wedge space 63 communicating with the chamber 46. The width in the radial direction of the one wedge space 63 is determined so that the width in the B direction, which is the radial direction, gradually becomes narrower toward the other wedge space 64 in the rotation direction R. The width of the other wedge space 64 in the B direction is determined so that the width of the other wedge space 64 in the B direction gradually decreases in the rotation direction R toward the one wedge space 63. Viscous flow passing through a pair of wedge spaces 63 and 64 5 is adapted to determine the direction B the width of the pair of wedge spaces 63 and 64 by its viscosity by deflecting the elastic vane 43 elastically.

  Due to the convex surface 61 and the concave surface 62 described above, the elastic vane 43 is formed in an arc shape by gradually decreasing the thickness in the R1 and R2 directions, which are also the circumferential direction R from the outer peripheral surface 4 toward the inner peripheral surface 2. The base 67 connected to the body 7 is gradually thinned from the free end 66 having the arcuate convex surface 65.

  The viscous fluid 5 passing through the pair of wedge spaces 63 and 64 passes through the pair of wedge spaces 64 and 63 narrowed from the other chamber 47 to the one chamber 46 in the rotation of the rotating body 7 with respect to the container 3 in the R1 direction. The flow is defined by the narrowed pair of wedge spaces 64 and 63 and generates a large flow resistance against the rotation in the R1 direction. In the rotation in the R2 direction, it flows through the pair of wedge spaces 63 and 64 expanded from one chamber 46 to the other chamber 47 and is defined by the expanded pair of wedge spaces 63 and 64, and in the R2 direction. A small flow resistance that resists rotation is generated.

  The elastic vane 44 that divides the chamber 45 and the chamber 48 is formed in the same manner as the elastic vane 43, and the viscous fluid 5 that passes through the pair of wedge spaces 63 and 64 in the elastic vane 44 also elastically moves the elastic vane 44. The width of the pair of wedge spaces 63 and 64 in the B direction is determined by bending the viscosity, and thus the viscous fluid 5 passing through the pair of wedge spaces 63 and 64 in the elastic vane 44 is: Due to the rotation of the rotating body 7 in the R1 direction relative to the container 3, the pair of wedge spaces 64 and 63 flow from the other chamber 45 through the pair of wedge spaces 64 and 63 narrowed to the one chamber 48. While being defined, a large flow resistance against the rotation in the R1 direction is generated, while the one chamber 48 in the rotation in the R2 direction of the rotating body 7 with respect to the container 3 is provided. Small flow resistance that flows through the pair of wedge spaces 63 and 64 expanded in the other chamber 45 and is defined by the expanded pair of wedge spaces 63 and 64 and resists rotation in the R2 direction. Is supposed to occur.

  The elastic vane 49 that partitions the chamber 41 into two chambers 45 and 46 adjacent to each other in the rotation direction R in cooperation with the elastic vanes 43 and 44 has an arcuate concave surface 71 complementary to the convex surface 61 of the elastic vane 43. A base 73 having a convex surface 61 of the vane 43 facing the rotational surface R in the rotational direction R and a concave surface 72 having a cross-section V or U shape facing the concave surface 62 of the elastic vane 44 in the rotational direction R; It has an elastically flexible tongue 75 which is formed integrally with the base 73 and faces the outer peripheral surface 4 of the rotating body 7 with an arcuate surface 74. A wedge space similar to the pair of wedge spaces 63 and 64 is formed between the outer circumferential surface 4 and the arcuate surface 74 of the tongue 75 having a radius of curvature larger than the radius of curvature of the outer peripheral surface 4. A pair of wedge cavities in the arcuate surface 74 of the tongue 75 Similarly to the elastic vane 43, the elastic vane 49 that forms the wedge space similar to the 63 and 64 has a relative rotation in the R1 direction of the rotating body 7 with respect to the container 3 from the chamber 45 through the pair of wedge spaces. While the flow of the viscous fluid 5 to 46 is allowed with a large resistance, the relative rotation in the R2 direction of the rotating body 7 with respect to the container 3 allows the flow of the viscous fluid 5 from the chamber 46 to the chamber 45 with a small resistance. It is like that.

  The elastic vane 50 that divides the chamber 42 into two chambers 47 and 48 that are adjacent to each other in the rotation direction R in cooperation with the elastic vanes 43 and 44 is also formed in the same manner as the elastic vane 49. Like the elastic vane 49, the elastic vane 50 that forms a pair of wedge spaces between the arcuate surface 74 of the tongue portion 75 and the arcuate surface 75 of the tongue 75 is the relative rotation of the rotating body 7 relative to the container 3 in the R1 direction. The viscous fluid 5 is allowed to flow from the chamber 47 to the chamber 48 through the wedge space with a large resistance, while the relative rotation of the rotating body 7 with respect to the container 3 in the R2 direction causes the viscous fluid from the chamber 48 to the chamber 47. 5 is allowed to flow with a small resistance.

  One end surface of the elastic vanes 43 and 44 in the A direction is in close contact with the side surface 25 of the flange portion 19 so as to be slidable in the R1 and R2 directions, and the other end surfaces of the elastic vanes 43 and 44 in the A direction are also included. The elastic vanes 49 and 50 are in close contact with the side surface 29 of the plate-like portion 30 so as to be slidable in the R1 and R2 directions, and the base 73 is integrally formed on the inner peripheral surface 2 of the cylindrical portion 15. Is formed integrally with the side surface 25 of the flange portion 19 at one end surface in the A direction, and the elastic vanes 49 and 50 are formed with the base portion 73 integrally formed on the inner peripheral surface of the protrusion 31. Is one end face 81 in the A direction, and the base 73 is exactly liquid-tight to the other end face 82 in the A direction of the elastic vanes 49 and 50 formed integrally with the inner peripheral surface 2 of the cylindrical portion 15. In contact with the side face 29 of the plate-like portion 30 at the other end face in the A direction It is formed in.

  For example, as shown in FIGS. 8 to 10, the above rotary damper 1 includes a seat portion 86 fixedly attached to a vehicle body 85 of an automobile, and the seat portion 86 in the R1 and R2 directions centered on the axis O. It is used as a braking mechanism against rotation in the R1 and R2 directions of the seat portion 86 of the backrest portion 87 in the vehicle seat 88 having a backrest portion 87 that is rotatably connected and attached. In this case, the rotary damper 1 has a plate-like portion 30 of the lid body 22 via a screw 91 inserted through the through-holes 27 and 28, and the container 3 is one of the seat portion 86 and the backrest portion 87. In this example, the rotating body 7 is fixed to the seat portion 86, while the rotating body 7 is connected to the other of the seat portion 86 and the backrest portion 87 via the rotating shaft 93 inserted into the hollow portion 35 of the rotating body 7. In this example, it is used by being connected to the backrest 87. The rotating shaft 93 having the other end fixed to the backrest portion 87 is connected to the rotating body 7 with the unevenness (serration) 94 provided on the one end portion 92 fitted into the unevenness 37 of the rotating body 7. The rotating body 7 connected to the backrest portion 87 via the rotating shaft 93 and, more specifically, the unevenness 37 and the unevenness 94 of the rotating shaft 93 fitted to the unevenness 37 is R1 of the rotating shaft 93. The rotation body 7 is connected and fixed to the backrest portion 87 in this way by rotating in the same direction by the rotation in the R2 direction, and hence the rotation of the backrest portion 87 in the R1 and R2 directions.

  In a vehicle seat 88 that includes a seat 86 attached to a vehicle body 85 and a backrest 87 that is rotatably connected to the seat 86, the backrest 87 is orthogonal to the front-rear direction. From an initial rotation position P0 inclined backward by a predetermined angle α, for example, α = 25 ° with respect to the vertical plane 95, to a folding rotation position P1, inclined forward by a predetermined angle β, for example, β = 90 °, with respect to the vertical surface 95. It is connected to the seat 86 so as to be rotatable about the axis O in the R1 and R2 directions. At the initial rotation position P0, rotation in the R1 and R2 directions is prohibited by a lock mechanism that can be unlocked (not shown). When the lock mechanism is unlocked, from the initial rotation position P0 to the folding rotation position P1, a pair of wedge spaces 63 and 64 by elastic vanes 43 and 44, 49 and 50 are provided. It is configured to rotate in the direction R1 against the flow resistance of the relatively large viscous fluid 5 passing through each pair of wedge spaces including the wedge space 63 and the folding position P1 to the initial rotation position P0. 64 is rotated in the R2 direction by manual rotation against the flow resistance of the relatively small viscous fluid 5 passing through each pair of wedge spaces including 64.

  In the above rotary damper 1 that functions as a one-way rotary damper, the backrest portion 87 rotates in the R1 direction by unlocking the lock mechanism at the rotational position of the rotating body 7 (corresponding to the initial rotational position P0) shown in FIG. When the rotating body 7 is rotated in the R1 direction with respect to the container 3 so as to expand the chambers 46 and 48 while reducing the chambers 45 and 47, the concave surfaces 62 and 44 of the elastic vanes 43 and 44 are Since the pressure of the viscous fluid 5 is applied to the concave surfaces 72 of the elastic vanes 49 and 50, the free end 66 side, which is the other end side of the elastic vanes 43 and 44, is placed on the inner peripheral surface 2 of the container 3. The elastic vanes 43 and 44 and the elastic vanes 49 and 50 are arranged so that the tongue 75 side of 49 and 50 approaches the outer peripheral surface 4 of the rotating body 7 to reduce each pair of wedge spaces including the pair of wedge spaces 63 and 64. As a result of the sexual deformation, the viscous fluid 5 passes through each pair of wedge spaces, including a reduced pair of wedge spaces 63 and 64, from chambers 45 and 47, respectively, to chambers 48 and 46, respectively, and chambers 46 and 48, respectively. To the rotation of the rotating body 7 in the R1 direction by applying a large braking force due to the relatively large flow resistance of the viscous fluid 5 passing through each of the pair of wedge spaces including the reduced wedge spaces 63 and 64. Is slowly rotated to the folding rotation position P1 in the same direction, while the backrest 87 is manually rotated in the R2 direction at the rotation position of the rotating body 7 (corresponding to the folding rotation position P1) shown in FIG. When the rotary body 7 is rotated in the R2 direction with respect to the container 3 so as to reduce the chambers 46 and 48, the curved convex surfaces 61 and elasticities of the elastic vanes 43 and 44 are elastic. Bae Since the pressure of the viscous fluid 5 is applied to the concave surfaces 71 of 49 and 50, the free end portions 66 of the elastic vanes 43 and 44 are connected to the tongue 75 of the elastic vanes 49 and 50 from the inner peripheral surface 2 of the container 3. As a result, the elastic vanes 43 and 44 and the elastic vanes 49 and 50 are elastically deformed so as to widen the pair of wedge spaces including the pair of wedge spaces 63 and 64 away from the outer peripheral surface 4 of the rotating body 7, respectively. 5 flows through each pair of wedge spaces including a pair of expanded wedge spaces 63 and 64 from each of chambers 46 and 48 to each of chambers 47 and 45 and each of chambers 45 and 47. Since the small braking force by the relatively small flow resistance of the viscous fluid 5 passing through each pair of wedge spaces 63 and 64 including the pair of wedge spaces 63 and 64 is given to the rotation of the rotating body 7 in the R2 direction, the backrest portion 87 has a small hand. To power It is further rotated to the initial rotation position P0.

  According to such a rotary damper 1, when the backrest portion 87 is rotated from the initial rotation position P0 to the folding rotation position P1, the vane means 8 can generate a large flow resistance in the viscous fluid 5, and as a result, the backrest portion Appropriate resistance can be given to rotation in the direction toward the folding rotation position P1 of the 87, and collision of the backrest 87 at the folding rotation position P1 can be avoided, while the backrest 87 is manually moved from the folding rotation position P1. It can be easily rotated to the initial rotation position P0.

  Further, in the rotary damper 1 functioning as a one-way damper, the viscous fluid 5 whose viscosity decreases with an increase in temperature is caused by each pair of wedges including a pair of wedge spaces 63 and 64 when the rotating body 7 rotates in the R1 and R2 directions. For example, when the viscous fluid 5 whose viscosity has increased from the normal temperature at low temperature passes through the wedge spaces 63 and 64 because it passes through the space, the viscous fluid 5 in the wedge spaces 63 and 64 is used. The elastic vane 43 is greatly elastically deformed so that the free end 66 side of the elastic vane 43 is further away from the inner peripheral surface 2 of the container 3 than at normal temperature due to the increase in pressure, and the wedge spaces 63 and 64 are compared with those at normal temperature. As a result of greatly expanding, the flow resistance is increased by increasing the viscosity of the viscous fluid 5 itself and the flow resistance is decreased by expanding the wedge spaces 63 and 64, so that braking at normal temperature can be maintained despite the low temperature. When the viscous fluid 5 whose viscosity is lower than that at normal temperature passes through the wedge spaces 63 and 64 under high temperature, the free end 66 side of the elastic vane 43 is accommodated by the pressure reduction of the viscous fluid in the wedge spaces 63 and 64. As a result of the elastic vane 43 being elastically deformed small and narrowing the wedge spaces 63 and 64 so as to approach the inner peripheral surface 2 of the body 3 from the normal temperature, the flow resistance is reduced due to a decrease in the viscosity of the viscous fluid 5 itself, and the wedge space 63 and The increase in flow resistance due to the reduction of 64 makes it possible to maintain braking at normal temperature regardless of high temperature, and therefore, braking generated does not depend on temperature and does not change at high or low temperatures. As a result, the backrest portion 87 can be reliably rotated to the folding rotation position P1, and the backrest portion 87 can be rotated back to the initial rotation position P0 with a certain small manual force. Can.

  The vane means 8 of the rotary damper 1 described above has two pairs of elastic vanes 43 and 44 arranged 49 and 50. However, the rotary damper of the present invention includes a pair of elastic vanes 43 and 44 and an elastic vane 49 or 50, or three or more pairs of elastic vanes, and the rotary damper 1 rotates with the arcuate surface 74 of each tongue 75 of the elastic vanes 49 and 50. A pair of wedge spaces are formed between the outer peripheral surface 4 of the body 7 and the arcuate surface 74 of each tongue 75 of the elastic vanes 49 and 50 and the outer peripheral surface 4 of the rotating body 7 are connected to R1. Further, the pair of wedge spaces may be prevented from being brought into frictional contact with each other so as to be slidable in the R2 direction.

DESCRIPTION OF SYMBOLS 1 Rotary damper 2 Inner peripheral surface 3 Container 4 Outer peripheral surface 5 Viscous fluid 6 Space 7 Rotating body 8 Vane means 41, 42, 45, 46, 47, 48 Chamber 43, 44, 49, 50 Elastic vane

Claims (4)

  Viscosity whose viscosity decreases as the temperature rises between the container having a cylindrical inner peripheral surface and the cylindrical inner peripheral surface of the container and the cylindrical outer peripheral surface concentric with the inner peripheral surface In the relative rotation in one direction of the rotating body with respect to the container and the rotating body arranged to be relatively rotatable with respect to the container so as to form a space for containing the fluid, the viscous fluid In order to produce a flow resistance smaller than the flow resistance in the relative rotation in the other direction, which is opposite to the relative rotation in one direction of the rotating body with respect to the storage body. Vane means disposed in a space for accommodating a viscous fluid between the cylindrical inner peripheral surface of the body and the cylindrical outer peripheral surface of the rotating body. Two spaces for accommodating viscous fluid between the inner peripheral surface and the cylindrical outer peripheral surface of the rotor A pair of elastic vanes and another elastic vane that further divides at least one of the two chambers partitioned by the pair of elastic vanes into two chambers. Each of them has a curved convex surface that is connected to the outer peripheral surface of the rotating body at one end and is convex in a direction opposite to the relative rotation in one direction of the rotating body with respect to the container, and corresponds to this convex surface. One end portion is connected to the outer peripheral surface of the rotating body and has a curved concave surface extending along the convex surface, and the convex surface is a rotation of the rotating body relative to the container on the other end side. A circular convex surface is formed between the inner circumferential surface of the container and a pair of wedge spaces facing each other in the direction, and the circular convex surface corresponds to the circle in the rotation direction of the relative rotation of the rotating body with respect to the container. Two adjacent arcs The other of the two chambers adjacent to each other with the radial width of one wedge space communicating with one of the two chambers sandwiching the arcuate convex surface in the rotational direction of the relative rotation of the rotating body with respect to the container The width in the radial direction of the one wedge space is determined so as to gradually become narrower toward the other wedge space communicating with the circle, and the circle in the rotational direction of the relative rotation of the rotating body with respect to the container is determined. The radial width of the other wedge space communicating with the other of the two chambers adjacent to each other with the arc-shaped convex surface in-between is such that the arc-shaped convex surface is interposed in the rotational direction of the relative rotation of the rotating body with respect to the container. The width in the radial direction of the other wedge space is determined so as to gradually narrow toward one wedge space communicating with one of the two adjacent chambers. The viscous fluid that passes through impacts each of the pair of elastic vanes. A rotary damper that is sexually bent and that determines the radial width of a pair of wedge spaces based on its viscosity.   The rotary damper according to claim 1, wherein the concave surface extends along the convex surface so as to gradually approach the convex surface from one end portion to the other end portion of the convex surface.   The rotary damper according to claim 1 or 2, wherein the arcuate convex surface has a radius of curvature smaller than a radius of curvature of the inner peripheral surface of the container.   The other elastic vane is elastically provided with a base formed integrally on the inner peripheral surface of the container, and an arcuate surface formed integrally with the base and facing the outer peripheral surface of the rotating body. The rotary damper according to any one of claims 1 to 3, further comprising a flexible tongue portion.

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