JP2012255509A - Rotary damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a rotary damper capable of suppressing the variation of torque.SOLUTION: A rotary damper 10 houses a rotor 14 rotatably in a housing 12 having a bottom 12A, and a cam ring 16 is rotatably provided between the housing 12 and rotor 14. An inclined surface 30 is formed on a slide surface 14A of the rotor 14 with the cam ring 16. An inclined surface 40 is formed on a slide surface 16B of the cam ring 16 with the rotor 14. When the 14 rotor and the housing 12 are relatively rotated, the inclined surface 30 of the rotor 14 and the inclined surface 40 of the cam ring 16 slide so that the rotor 14 presses the cam ring 16 to the direction of the slide surface 12C of the housing 12. As a result, a change in the clearance between the slide surface 12C of the housing 12 on which viscous fluid is applied and the slide surface 16B of the cam ring 16 is eliminated, and the variation of torque is suppressed.

Description

  The present invention relates to a rotary damper that brakes rotation by the viscous resistance of a viscous fluid.

  Conventionally, as a rotary damper, there is, for example, Patent Document 1. In this prior art, a viscous fluid is filled in a gap formed by a rotating body and a fixed body.

Japanese Patent No. 3421484

  However, in Patent Document 1, an annular ridge provided around the outer periphery of the rotating body is rotatably engaged with an annular step provided around the upper inner periphery of the fixed body. For this reason, there is a possibility that the relative movement amount (backlash) between the rotating body and the fixed body along the rotation axis direction may increase. Therefore, it is necessary to eliminate the change in the clearance between the sliding surface of the rotating body and the sliding surface of the fixed body, which is caused by the relative movement amount between the rotating body and the fixed body along the rotation axis direction, and to suppress the torque variation. is there.

  In view of the above fact, an object of the present invention is to obtain a rotary damper capable of suppressing variation in torque.

  A rotary damper according to a first aspect of the present invention includes a first member having a cylindrical shape having a bottom, a second member rotatably accommodated in the first member, the first member, and the second member. A sliding member that is rotatably provided between the first member and a sliding surface that slides on the sliding surface of the first member; and each of the second member and the sliding member. A contact portion formed on one of the sliding surfaces, and formed on the other of the sliding surfaces of the second member and the sliding member, and by the relative rotation of the first member and the second member, The second member and the sliding member have an inclined surface that slides on the contact portion and presses the sliding member toward the sliding surface of the first member by relative rotation of the second member and the sliding member.

  In the rotary damper according to the first aspect of the present invention, the second member is rotatably accommodated in the cylindrical first member having the bottom, and the sliding member is interposed between the first member and the second member. Is provided rotatably, and a viscous fluid is applied to the sliding surface of the sliding member that slides with the sliding surface of the first member. In addition, a contact portion is formed on one of the sliding surfaces of the second member and the sliding member, and an inclined surface is formed on the other, and the first member and the second member are rotated relative to each other. When the second member and the sliding member rotate relative to each other, the inclined surface and the contact portion slide to press the sliding member toward the sliding surface of the first member. For this reason, when the first member and the second member rotate relative to each other, the sliding member is pressed and moved toward the sliding surface of the first member, so that the sliding surface of the sliding member and the first member are moved. There is no change in the clearance with the sliding surface, and it is kept constant. As a result, variation in torque of the rotary damper is suppressed.

  The rotary damper according to a second aspect of the present invention includes a cylindrical first member having a bottom, a second member rotatably accommodated in the first member, the first member, and the second member. A sliding member that is rotatably provided between the first member and the sliding surface of the second member, and a sliding surface that slides on the sliding surface of the second member; and each of the first member and the sliding member. A contact portion formed on one of the sliding surfaces, and formed on the other of the sliding surfaces of the first member and the sliding member, and by the relative rotation of the first member and the second member, The first member and the sliding member have an inclined surface that slides on the contact portion and presses the sliding member toward the sliding surface of the second member by relative rotation of the first member and the sliding member.

  In the rotary damper of the present invention according to claim 2, the second member is rotatably accommodated in the cylindrical first member having a bottom portion, and the sliding member is interposed between the first member and the second member. Is provided rotatably, and a viscous fluid is applied to the sliding surface of the sliding member that slides with the sliding surface of the second member. In addition, an abutting portion is formed on one of the sliding surfaces of the first member and the sliding member, and an inclined surface is formed on the other, and when the first member and the second member rotate relative to each other, When the first member and the sliding member rotate relative to each other, the inclined surface and the contact portion slide to press the sliding member toward the sliding surface of the second member. For this reason, when the first member and the second member rotate relative to each other, the sliding member is pressed and moved toward the sliding surface of the second member, so that the sliding surface of the sliding member and the second member There is no change in the clearance with the sliding surface, and it is kept constant. As a result, variation in torque of the rotary damper is suppressed.

  According to a third aspect of the present invention, in the rotary damper according to the first or second aspect, the inclined surface is formed by the relative rotation in one direction between the second member or the first member and the sliding member. The sliding member is pressed against the sliding surface side of the first member or the second member, and the sliding member is also moved by relative rotation in the other direction of the second member or the first member and the sliding member. It is a pair of inclined surfaces which press to the sliding surface side of the first member or the second member.

  In the rotary damper of the present invention according to claim 3, the sliding surface of the sliding member and the first member with respect to relative rotation in one direction and the other direction of the first member and the second member by the pair of inclined surfaces. Alternatively, the clearance with the sliding surface of the second member is not changed and is kept constant. As a result, variation in torque of the rotary damper is suppressed in both rotations in one direction and the other direction.

  According to a fourth aspect of the present invention, in the rotary damper according to the first or second aspect, the inclined surface is formed by the relative rotation in one direction between the second member or the first member and the sliding member. A first inclined surface that presses the sliding member toward the sliding surface of the first member or the second member, and in addition to the first inclined surface, the second member or the first member and the sliding member A second slope that slides on an inclined surface formed on the contact portion by relative rotation in the other direction with the moving member and pulls the sliding member back to the opposite side of the sliding surface of the first member or the second member. Has a surface.

  In the rotary damper according to the fourth aspect of the present invention, in the relative rotation in one direction between the second member or the first member and the sliding member, the sliding member is moved by sliding between the first inclined surface and the contact portion. Press toward the sliding surface of the first member or the second member. On the other hand, in the relative rotation of the second member or the first member and the sliding member in the other direction, the second inclined surface slides with the inclined surface, and the sliding member becomes the sliding surface of the first member or the second member. Pull back to the opposite side. For this reason, the rotational torque in the other direction is reduced with respect to the rotational torque in one direction relative to the first member and the second member, and a one-way rotational damper is obtained.

  According to a fifth aspect of the present invention, in the rotary damper according to any one of the first to fourth aspects, the sliding surface of the first member or the second member, the sliding surface of the sliding member, A recess for filling the viscous fluid was formed in at least one of the two.

  In the rotary damper according to the fifth aspect of the present invention, the viscous fluid is filled in the concave portion formed in at least one of the sliding surface of the first member or the second member and the sliding surface of the sliding member. For this reason, the viscous fluid with which the recessed part was filled can be supplied to the sliding surface of a sliding member, and the sliding surface of a 1st member or a 2nd member. As a result, the durability of the rotary damper is improved.

  According to a sixth aspect of the present invention, in the rotary damper according to the fifth aspect, a plurality of the recesses are arranged at predetermined intervals along a relative rotational direction of the first member or the second member and the sliding member. ing.

  In the rotary damper according to the sixth aspect of the present invention, a plurality of recesses for filling the viscous fluid are arranged at predetermined intervals along the relative rotation direction of the first member or the second member and the sliding member. . As a result, the viscous fluid filled in the recesses can be supplied over the entire area of the sliding surface of the first member or the second member and the sliding surface of the sliding member. As a result, the durability of the rotary damper is further improved.

  According to a seventh aspect of the present invention, in the damper according to any one of the first to sixth aspects, the sliding surface of the first member or the second member and the sliding surface of the sliding member are It is inclined with respect to the rotation axis of relative rotation.

  In the rotary damper, when the viscosity (μ) of the viscous fluid applied to the sliding surface is high and the sliding member and the first member or the second member rotate relatively at high speed, the sliding member is caused by the resistance of the viscous fluid. Tends to be repelled from the first member or the second member. That is, a repulsive force is generated that moves the sliding member in a direction away from the first member or the second member along the rotation axis of the relative rotation. For this reason, it is conceivable that the inclination angle of the inclined surface sliding with the contact portion is reduced to facilitate the movement of the sliding member toward the sliding surface of the first member or the second member. When the inclination angle of the inclined surface that slides is reduced, the idling angle immediately before the rotary damper works increases. For this reason, the sliding member is slid along the rotational axis of the relative rotation against the repulsive force without reducing the inclination angle of the inclined surface sliding with the contact portion. It is necessary to generate a pressing force that moves (pushes back) the moving surface.

  On the other hand, in the rotary damper according to the seventh aspect of the present invention, the sliding surface of the first member or the second member to which the viscous fluid is applied and the sliding surface of the sliding member are a rotation shaft of relative rotation. It is inclined with respect to. For this reason, when the sliding surface to which the viscous fluid is applied is perpendicular to the rotation axis of relative rotation, the pressing force f (= μN: generated by sliding between the inclined surface and the contact portion). N is a pressing force F according to the present invention (F> f) as compared to a pressing force generated by sliding between the inclined surface and the contact portion.

  That is, the sliding surface of the first member or the second member and the sliding surface of the sliding member are inclined at an angle β (0 ° <β <90 °) with respect to the normal to the rotation axis of the relative rotation. In this case, the pressing force F that moves the sliding member along the rotation axis of the relative rotation toward the sliding surface of the first member or the second member is 1 / cos β of the pressing force f (F = μN). / Cosβ). Therefore, even if N is constant, the pressing force F can be increased by increasing the angle β. As a result, the pressing force F that moves the sliding member toward the sliding surface of the first member or the second member can be increased, so that even if the viscosity of the viscous fluid increases, the sliding member becomes the first member. Alternatively, it can be prevented from being bounced from the second member. Therefore, since it is not necessary to reduce the inclination angle of the inclined surface that slides with the contact portion, it is possible to prevent an increase in the idling angle immediately before the rotary damper is effective, which occurs when the inclination angle is reduced.

  The invention according to claim 8 is the damper according to any one of claims 1 to 7, wherein the shaft portion formed on one of the first member or the second member is the first member or the first member. The first member and the second member are assembled by being inserted into a circular hole formed in the other of the two members.

  In the rotary damper of the present invention according to claim 8, by inserting the shaft portion formed in one of the first member or the second member into the circular hole formed in the other of the first member or the second member, The first member and the second member can be assembled. For this reason, the workability of assembling the rotary damper is improved.

  According to a ninth aspect of the present invention, in the damper according to any one of the first to eighth aspects, gears are formed on the outer peripheral portion of the first member and the outer peripheral portion of the second member.

  In the rotary damper according to the ninth aspect of the present invention, the rotational force input to one of the gear formed on the outer peripheral portion of the first member and the gear formed on the outer peripheral portion of the second member is braked. , And can be output as the rotational force of the other gear. For this reason, a rotation damper can be incorporated in the rotational force transmission part to which the some gearwheel was connected.

  Since the rotary damper according to the first aspect of the present invention has the above-described configuration, it is possible to suppress variations in torque.

  Since the rotary damper according to the second aspect of the present invention has the above-described configuration, it is possible to suppress variations in torque.

  Since the rotary damper according to the third aspect of the present invention has the above-described configuration, it is possible to suppress variations in the torque of the rotary damper in both rotations in one direction and the other direction.

  Since the rotary damper according to the fourth aspect of the present invention has the above configuration, it can be a one-way rotary damper.

  Since the rotary damper according to the fifth aspect of the present invention has the above-described configuration, durability can be improved.

  Since the rotary damper according to the sixth aspect of the present invention has the above-described configuration, the durability can be further improved.

  Since the rotary damper according to the seventh aspect of the present invention has the above-described configuration, the sliding member can be prevented from being repelled from the first member or the second member even when the viscosity of the viscous fluid increases.

  Since the rotary damper according to the eighth aspect of the present invention has the above-described configuration, the assembly workability can be improved.

  Since the rotary damper of the present invention according to the ninth aspect has the above-described configuration, the rotary damper can be incorporated into a rotational force transmission unit to which a plurality of gears are connected.

It is the perspective view which made the section which shows the rotating damper concerning a 1st embodiment of the present invention a section. It is a disassembled perspective view which made the cross section the part which shows the rotary damper which concerns on 1st Embodiment of this invention. It is the side view which made the section which shows the rotation damper concerning a 1st embodiment of the present invention a section. It is a disassembled side view which shows the rotor and cam ring of the rotary damper which concern on 1st Embodiment of this invention. It is a perspective view which shows the cam ring of the rotary damper which concerns on 1st Embodiment of this invention. It is a top view which shows the sliding surface of the cam ring of the rotary damper which concerns on 1st Embodiment of this invention. It is a perspective view which shows the housing of the rotary damper which concerns on 1st Embodiment of this invention. It is the perspective view which made a part the section which shows the rotation damper concerning a 2nd embodiment of the present invention. It is a disassembled perspective view which made the cross section the part which shows the rotary damper which concerns on 2nd Embodiment of this invention. It is a disassembled side view which shows the rotor and cam ring of the rotary damper which concern on 2nd Embodiment of this invention. It is a perspective view which shows the cam ring of the rotary damper which concerns on 2nd Embodiment of this invention. It is the perspective view which made a part the cross section which shows the rotary damper which concerns on 3rd Embodiment of this invention. It is a sectional side view which shows the rotary damper which concerns on 3rd Embodiment of this invention. It is a disassembled perspective view which made the cross section the part which shows the rotary damper which concerns on 3rd Embodiment of this invention. It is a disassembled perspective view which made the cross section the part which shows the rotary damper which concerns on 3rd Embodiment of this invention.

(First embodiment)
Next, a first embodiment of the rotary damper of the present invention will be described with reference to FIGS.
In the drawings, members (components) having the same or corresponding functions are denoted by the same reference numerals and description thereof is omitted as appropriate. 1 and 2 are omitted for easy understanding of the shape of the member.

  As shown in FIGS. 1 and 2, the rotary damper 10 of the present embodiment includes a housing 12 as a first member, a rotor 14 as a second member, and a cam ring 16 as a sliding member.

  As shown in FIG. 7, the housing 12 has a cylindrical shape having a bottom portion 12A, and a cylindrical shaft portion 12B is erected at the center of the bottom portion 12A. A concave portion 20 is formed in a ring shape along the circumferential direction on the outer peripheral portion of the shaft portion 12B. Further, the inner peripheral surface of the bottom portion 12A of the housing 12 is a sliding surface 12C with the cam ring 16, and in the circumferential direction of the sliding surface 12C at the radial center of the ring-shaped sliding surface 12C. A single protrusion 18 is formed along the line. Further, a gear 22 is formed on the outer peripheral portion of the housing 12.

  As shown in FIG. 2, the rotor 14 has a disk shape, and a circular hole 24 is formed in the center. The shaft portion 12B of the housing 12 is inserted into the circular hole 24 of the rotor 14, and the rotor 14 is rotatably supported by the shaft portion 12B of the housing 12. A gear 26 is formed on the outer periphery of the rotor 14.

  The configuration in which the rotor 14 is rotatably housed in the housing 12 is not limited to the above configuration in which the shaft portion 12B of the housing 12 is inserted into the circular hole 24 of the rotor 14.

  As shown in FIG. 3, a convex portion 27 is formed in a ring shape along the circumferential direction at an end portion of the inner peripheral portion of the circular hole 24 of the rotor 14 opposite to the bottom portion 12 </ b> A of the housing 12. The rotor 14 is held by the housing 12 by the convex portion 27 engaging with the concave portion 20 of the housing 12. That is, even if the rotor 14 moves slightly in the axial direction with respect to the housing 12, it does not fall out.

  As shown in FIG. 2, the cam ring 16 has a ring shape (annular shape), and is rotatably provided between the housing 12 and the rotor 14. More specifically, a cylindrical convex portion 14B is formed at the center portion of the sliding surface 14A with the cam ring 16 in the rotor 14, and this convex portion 14B is inserted into the inner peripheral portion of the cam ring 16. ing. The shaft portion 12B of the housing 12 is inserted into the inner peripheral portion of the convex portion 14B communicating with the circular hole 24.

  A convex portion 34 having inclined surfaces 30 and 32 is formed on the outer peripheral side edge portion of the sliding surface 14 </ b> A of the rotor 14. In addition, the inclined surfaces 30 and 32 are formed at two positions separated by 180 degrees along the circumferential direction of the sliding surface 14A. In addition, the inclined surfaces 30 and 32 are not limited to two places.

  As shown in FIG. 4, the convex portion 34 having the inclined surfaces 30 and 32 has a trapezoidal shape in which the length L1 along the circumferential direction of the rotor 14 extends from the tip portion 34A toward the root portion 34B. For this reason, the inclination direction of one inclined surface 30 and the inclination direction of the other inclined surface 32 are opposite directions. In the present embodiment, the absolute value of the inclination angle θ1 (0 ° <θ1 <90 °) of the inclined surface 30 and the absolute value of the inclination angle θ2 (0 ° <θ2 <90 °) of the inclined surface 32 are the same. However, the absolute value of the inclination angle θ1 of the inclined surface 30 may be different from the absolute value of the inclination angle θ2 of the inclined surface 32.

  As shown in FIG. 5, a concave portion 44 having inclined surfaces 40 and 42 as contact portions is formed on the sliding surface 16 </ b> A of the cam ring 16 with the rotor 14. Two recesses 44 are formed at positions spaced 180 degrees along the circumferential direction of the sliding surface 16A. Note that the number of the concave portions 44 is not limited to two as long as the number of the convex portions 34 is the same.

  Further, the inclined surface 30 and the inclined surface 40 are inclined in the same direction, and the inclined surface 32 and the inclined surface 42 are inclined in the same direction. In the rotary damper 10 in the assembled state, the convex portion 34 of the rotor 14 is provided. Are inserted into the recess 44 of the cam ring 16 and engaged with each other.

  As shown in FIG. 2, in the radial direction center of the sliding surface 16B with the housing 12 in the cam ring 16, a single recess 48 is provided along the circumferential direction of the sliding surface 16B in the circumferential direction of the sliding surface 16B. Are formed along. As shown in FIG. 3, in the rotary damper 10 in the assembled state, the concave portion 48 of the cam ring 16 and the convex portion 18 of the housing 12 are engaged.

  As shown in FIG. 6, the sliding surface 16B of the cam ring 16 is formed with a recess 50 having a circular opening. A plurality of the recesses 50 are arranged at predetermined intervals along the relative rotation direction of the housing 12 and the cam ring 16 in the circumferential direction of the sliding surface 16B. In addition, the shape of the opening part of the recessed part 50 is not limited to circular, It is good also as other shapes, such as a rectangle and a long hole along the circumferential direction of the sliding face 16B. Further, the number and interval of the recesses 50 are not limited.

  As shown in FIG. 3, a viscous fluid 54 such as grease is applied to the sliding surface 16B of the cam ring 16 with the housing 12. The concave portion 50 is hemispherical, and the concave portion 50 is filled with a viscous fluid 54. In addition, the recessed part 50 is not limited to a hemisphere, Other shapes, such as a column shape, may be sufficient.

  Therefore, when the rotor 14 rotates in one direction (the direction of arrow A in FIGS. 1, 2, and 4), the inclined surface 30 of the rotor 14 comes into contact with the inclined surface 40 of the cam ring 16, and the inclined surface 30 and the inclined surface 40 are brought into contact with each other. It comes to slide. For this reason, the rotor 14 presses the cam ring 16 in the direction of the sliding surface 12C of the housing 12 (the direction of arrow B in FIG. 3). Further, when the rotor 14 rotates in the other direction (the direction of arrow C in FIGS. 1, 2, and 4), the inclined surface 32 of the rotor 14 comes into contact with the inclined surface 42 of the cam ring 16, and the inclined surface 32 and the inclined surface 42 are brought together. It comes to slide. For this reason, the rotor 14 presses the cam ring 16 in the direction of the sliding surface 12C of the housing 12 (the direction of arrow B in FIG. 3).

  In addition, the convex part 27 of the rotor 14 and the concave part 20 of the housing 12 are engaged. For this reason, even if the rotor 14 presses the cam ring 16 in the direction of the sliding surface 12C of the housing 12 (the direction of arrow B in FIG. 3), the rotor 14 and the housing 12 do not come off. As a result, when the rotor 14 rotates relative to the housing 12 in one direction (arrow A direction) or the other direction (arrow C direction), the sliding surface 12C of the housing 12 and the sliding surface 16B of the cam ring 16 The clearance does not change and is kept constant (approximately 0).

(Action / Effect)
Next, the operation of this embodiment will be described.
In the rotary damper 10 of this embodiment, a rotor 14 is rotatably accommodated in a cylindrical housing 12 having a bottom 12A, and a cam ring 16 is rotatably provided between the housing 12 and the rotor 14. ing. Further, inclined surfaces 30 and 32 are formed on the sliding surface 14A of the rotor 14 with the cam ring 16, and inclined surfaces 40 and 42 as contact portions are formed on the sliding surface 16A of the cam ring 16 with the rotor 14. Is formed. For this reason, when the rotor 14 rotates in one direction (the arrow A direction in FIGS. 1, 2, and 4), the inclined surface 30 of the rotor 14 and the inclined surface 40 of the cam ring 16 slide, and the rotor 14 moves the cam ring 16. Press in the direction of the sliding surface 12C of the housing 12 (the direction of arrow B in FIG. 3). When the rotor 14 rotates in the other direction (the direction of arrow C in FIGS. 1, 2, and 4), the inclined surface 32 of the rotor 14 and the inclined surface 42 of the cam ring 16 slide, and the rotor 14 houses the cam ring 16. 12 is pressed in the direction of the sliding surface 12C (the direction of arrow B in FIG. 3).

  As a result, when the rotor 14 rotates relative to the housing 12 in one direction (arrow A direction) or the other direction (arrow C direction), the sliding surface 12C of the housing 12 and the sliding surface 16B of the cam ring 16 Clearance changes are eliminated and kept constant (approximately 0). For this reason, in the rotary damper 10 of the present embodiment, torque variation can be suppressed.

  That is, in the rotary damper 10 according to the present embodiment, torque variation in the rotary damper 10 can be suppressed in both directions in one direction and the other direction.

  Further, in the rotary damper 10 of the present embodiment, an elastic body such as a spring is not used when the cam ring 16 is pressed in the direction of the sliding surface 12C of the housing 12 (the direction of arrow B in FIG. 3). For this reason, it is possible to suppress variations in the torque of the rotary damper caused by variations in the load of the elastic body and changes with time (sagging).

  Further, in the rotary damper 10 of the present embodiment, the concave fluid 50 formed in the sliding surface 16B of the cam ring 16 is filled with the viscous fluid 54. For this reason, the viscous fluid 54 filled in the recess 50 can be supplied to the sliding surface 16B of the cam ring 16 and the sliding surface 14A of the rotor 14. As a result, the durability of the rotary damper 10 can be improved.

  In the rotary damper 10 of the present embodiment, a plurality of recesses 50 for filling the viscous fluid 54 are arranged along the sliding surface 16B of the cam ring 16 at a predetermined interval. For this reason, the viscous fluid 54 filled in the recess 50 can be supplied over the entire area of the sliding surface 12C of the housing 12 and the sliding surface 16B of the cam ring 16. As a result, the durability of the rotary damper 10 can be further improved.

  In the rotary damper 10 of the present embodiment, the viscous fluid 54 may be applied to the sliding surface 16B of the cam ring 16. For this reason, in the rotary damper 10 of the present embodiment, the viscous fluid is less likely to leak and the viscous fluid is less likely to leak than the rotary damper configured to inject and fill the viscous fluid into the sliding portion between the cam ring 16 and the housing 12. The amount of use can be greatly reduced, and the cost can be significantly reduced.

  Further, in the rotary damper 10 of the present embodiment, the surface to which the viscous fluid 54 is applied on the sliding surface 16B of the cam ring 16 is only the outer peripheral side of the concave portion 48 on the sliding surface 16B, and the inner periphery of the concave portion 48 on the sliding surface 16B. Only the side can be selected for both the outer peripheral side and the inner peripheral side of the recess 48 in the sliding surface 16B. For this reason, the rotational damper 10 of three types (plurality) of torque variations can be set with the viscous fluid 54 having one viscosity.

  In the rotary damper 10 of the present embodiment, the shaft portion 12B formed in the housing 12 is inserted into the circular hole 24 formed in the rotor 14, so that the convex portion 27 of the rotor 14 and the concave portion 20 of the housing 12 are connected. Engage and the rotor 14 is assembled to the housing 12. For this reason, the rotary damper 10 can be easily assembled without using a special device. For this reason, the workability of assembling the rotary damper 10 is improved.

  Further, in the rotary damper 10 of the present embodiment, there is no portion where compression or press-fitting is performed during assembly. For this reason, generation | occurrence | production of the creep and wear in the rotation damper 10 is also suppressed.

  In the rotary damper 10 of the present embodiment, the rotational force input to one of the gear 22 formed on the outer peripheral portion of the housing 12 and the gear 26 formed on the outer peripheral portion of the rotor 14 is braked, and the other Can output as rotational force. For this reason, the rotary damper 10 can be incorporated in a rotational force transmission unit in which a plurality of gears are connected.

(Second Embodiment)
Next, a second embodiment of the rotary damper according to the present invention will be described with reference to FIGS.
In addition, about the same member as 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted. Also, the viscous fluid display in FIGS. 8 and 9 is omitted to facilitate understanding of the shape of the member.

  As shown in FIGS. 8 and 9, in the rotary damper 10 of the present embodiment, a convex portion 64 having a first inclined surface 60 as an inclined surface on the outer peripheral edge portion of the sliding surface 14 </ b> A with the cam ring 16 of the rotor 14. Is formed. Moreover, the 2nd inclined surface 62 is formed in the convex part 64, and the convex part 64 is formed in two places in the position 180 degree apart along the circumferential direction of 14 A of sliding surfaces. In addition, the convex part 64 is not limited to two places.

  As shown in FIG. 10, the convex portion 64 of the rotor 14 has a parallelogram shape in which the length L1 along the circumferential direction is constant from the tip portion 64A toward the root portion 64B, and the first inclined surface. The inclination angle α1 of 60 (0 ° <α1 <90 °) is equal to the inclination angle α2 of the second inclined surface 62 (0 ° <α2 <90 °). If the first inclined surface 60 and the second inclined surface 62 are inclined in the same direction, the inclination angle α1 of the first inclined surface 60 and the inclination angle α2 of the second inclined surface 62 may be different. .

  As shown in FIG. 11, on the sliding surface 16 </ b> A of the cam ring 16 with the rotor 14, an inclined surface 70 as a contact portion and a concave portion 74 having an inclined surface 72 are formed. Two recesses 74 are formed at positions spaced 180 degrees along the circumferential direction of the sliding surface 16A. Note that the number of the concave portions 44 is not limited to two as long as the number of the convex portions 34 is the same.

  Further, the inclined surface 60 and the inclined surface 70 are inclined in the same direction, and the inclined surface 62 and the inclined surface 72 are inclined in the same direction. In the rotary damper 10 in the assembled state, the convex portion 64 of the rotor 14. Are inserted into the recess 74 of the cam ring 16 and engaged with each other. Therefore, when the rotor 14 rotates in one direction (the direction of arrow A in FIGS. 8 to 10), the first inclined surface 60 of the rotor 14 and the inclined surface 70 of the cam ring 16 slide. For this reason, the rotor 14 presses the cam ring 16 in the direction of the sliding surface 12C of the housing 12 (the direction of arrow B in FIG. 8). Further, when the rotor 14 rotates in the other direction (the direction of arrow C in FIGS. 8 to 10), the second inclined surface 62 of the rotor 14 and the inclined surface 72 of the cam ring 16 slide. For this reason, the rotor 14 pulls the cam ring 16 back to the opposite side of the sliding surface 12C of the housing 12 (in the direction of arrow D in FIG. 8).

  In addition, the convex part 27 of the rotor 14 and the concave part 20 of the housing 12 are engaged. For this reason, the rotor 14 and the housing 12 do not come off, and when the rotor 14 rotates relative to the housing 12 in the direction of arrow A, the sliding surface 12C of the housing 12 and the sliding surface 16B of the cam ring 16 The change in the clearance is eliminated, and the variation in torque can be suppressed. On the other hand, when the rotor 14 rotates relative to the housing 12 in the direction of arrow C, the clearance between the sliding surface 12C of the housing 12 and the sliding surface 16B of the cam ring 16 increases, and the direction of the rotary damper 10 in the arrow C direction. Is lower than the rotational torque in the direction of arrow A.

(Action / Effect)
Next, the operation of this embodiment will be described.
In the rotary damper 10 of this embodiment, a rotor 14 is rotatably accommodated in a cylindrical housing 12 having a bottom 12A, and a cam ring 16 is rotatably provided between the housing 12 and the rotor 14. ing. A first inclined surface 60 and a second inclined surface 62 that are parallel to each other are formed on the sliding surface 14A of the rotor 14 with the cam ring 16, and the sliding surface 16A of the cam ring 16 with the rotor 14 is abutted against the sliding surface 14A. An inclined surface 70 and an inclined surface 72 are formed as contact portions. Therefore, when the rotor 14 rotates in one direction (the direction of arrow A in FIGS. 8 to 10), the first inclined surface 60 of the rotor 14 and the inclined surface 70 of the cam ring 16 slide, and the rotor 14 moves the cam ring 16. Press in the direction of the sliding surface 12C of the housing 12 (the direction of arrow B in FIG. 8).

  As a result, when the rotor 14 rotates relative to the housing 12 in the direction of arrow A, there is no change in the clearance between the sliding surface 12C of the housing 12 and the sliding surface 16B of the cam ring 16, and is constant (approximately 0). Kept. For this reason, in the rotary damper 10 of the present embodiment, torque variation can be suppressed.

  On the other hand, when the rotor 14 rotates in the other direction (the direction of arrow C in FIGS. 8 to 10), the second inclined surface 62 of the rotor 14 and the inclined surface 72 of the cam ring 16 slide, and the rotor 14 houses the cam ring 16. 12 is pulled back to the side opposite to the sliding surface 12C (in the direction of arrow D in FIG. 8). For this reason, when the rotor 14 rotates relative to the housing 12 in the direction of arrow C, the cam ring 16 moves in the direction of arrow D, and the clearance between the sliding surface 12C of the housing 12 and the sliding surface 16B of the cam ring 16 is increased. Becomes larger.

  As a result, in the rotary damper 10 of the present embodiment, the rotational torque in one direction (the direction of arrow A in FIGS. 8 to 10) of the relative rotation between the rotor 14 and the housing 12 is the other direction (arrow C in FIGS. 8 to 10). Direction) rotational torque is reduced. For this reason, in this embodiment, the one-way rotary damper 10 can be obtained.

(Third embodiment)
Next, a third embodiment of the rotary damper according to the present invention will be described with reference to FIGS.
In addition, about the same member as 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted. In addition, in FIG. 12, FIG. 14 and FIG. 15, the indication of the viscous fluid is omitted for easy understanding of the shape of the member.

  As shown in FIG. 12, the rotary damper 110 of the present embodiment includes a housing 112 as a first member, a rotor 114 as a second member, and a cam ring 116 as a sliding member.

  As shown in FIG. 14, the housing 112 has a cylindrical shape having a bottom portion 112A, and a cylindrical portion 112C is erected at the center of a sliding surface 112B of the bottom portion 112A with the rotor 114. A gear 122 is formed on the outer periphery of the housing 112.

  The rotor 114 has a cylindrical shape, and a partition wall 114A is formed on the inner peripheral portion of the central portion in the axial direction. In addition, a cylindrical shaft portion 114B is erected toward the housing 112 at the center of the partition wall 114A. A shaft portion 114B of the rotor 114 is inserted into a cylindrical portion 112C as a circular hole of the housing 112, and the rotor 114 is rotatably supported by the cylindrical portion 112C of the housing 112.

  The configuration in which the rotor 114 is rotatably housed in the housing 112 is not limited to the above configuration in which the shaft portion 114B of the rotor 114 is inserted into the cylindrical portion 112C of the housing 112.

  As shown in FIG. 13, the surface on the cam ring 116 side of the partition 114 </ b> A in the rotor 114 is a sliding surface 114 </ b> C with the cam ring 116. The sliding surface 114C is inclined at an angle β (0 ° <β <90 °) with respect to a perpendicular H to the rotating shaft 110A of the rotary damper 110.

  As shown in FIG. 14, the cam ring 116 has a ring shape (annular shape), and is rotatably provided between the housing 112 and the rotor 114. More specifically, a cylindrical portion 116A is formed to protrude toward the housing 112 at the center of the cam ring 116, and the shaft portion 114B of the rotor 114 is inserted into the cylindrical portion 116A. Further, on the outer peripheral side of the shaft portion 114B of the rotor 114, the tip end of the cylindrical portion 116A of the cam ring 116 and the tip end of the cylindrical portion 112C of the housing 112 are in contact.

  On the sliding surface 112B of the housing 112 with the cam ring 116, a convex portion 134 having inclined surfaces 130 and 132 is formed. In addition, the inclined surfaces 130 and 132 are formed at three positions at positions separated by 120 degrees along the circumferential direction of the sliding surface 112B. In addition, the inclined surfaces 130 and 132 are not limited to three places.

  The convex part 134 having the inclined surfaces 130 and 132 has a trapezoidal shape in which the length in the circumferential direction of the rotor 114 extends from the tip part 134A toward the root part 134B. For this reason, the inclination direction of one inclined surface 130 and the inclination direction of the other inclined surface 132 are opposite directions. In this embodiment, the absolute value of the inclination angle of the inclined surface 130 and the absolute value of the inclination angle of the inclined surface 132 are the same, but the absolute value of the inclination angle of the inclined surface 130 and the inclination angle of the inclined surface 132 are the same. It is good also as a structure from which an absolute value differs.

  As shown in FIG. 15, a recess 144 having inclined surfaces 140 and 142 as contact portions is formed on the sliding surface 116 </ b> B of the cam ring 116 with the housing 112. Three recesses 144 are formed at positions spaced 120 degrees along the circumferential direction of the sliding surface 116B. Note that the number of the concave portions 144 is not limited to three as long as the number is the same as the number of the convex portions 134.

  In addition, the inclined surface 130 and the inclined surface 140 are inclined in the same direction, and the inclined surface 132 and the inclined surface 142 are inclined in the same direction. In the assembled rotary damper 110, the convex portion 134 of the housing 112 is provided. Are inserted into the recesses 144 of the cam ring 116 so as to engage with each other.

  As shown in FIG. 13, the sliding surface 116 </ b> C of the cam ring 116 that slides with the sliding surface 114 </ b> C of the rotor 114 is also inclined at an angle β with respect to the perpendicular H to the rotating shaft 110 </ b> A of the rotary damper 110.

  As shown in FIG. 14, a concave surface 150 having a rectangular opening is formed on a sliding surface 116 </ b> C of the cam ring 116 with the rotor 114. A plurality of the recesses 150 are arranged at a predetermined interval along the relative rotation direction of the rotor 114 and the cam ring 116, which is the circumferential direction of the sliding surface 116C, and a predetermined amount also along the inclination direction of the sliding surface 116C. Multiple arrays are arranged at intervals. In addition, the shape of the opening part of the recessed part 150 is not limited to a rectangle, It is good also as other shapes, such as circular and a long hole along the circumferential direction of 116 C of sliding surfaces. Further, the number and interval of the recesses 150 are not limited.

  As shown in FIG. 13, a viscous fluid 54 such as grease is applied to the sliding surface 116C of the cam ring 116 with the rotor 114. The concave portion 150 has a rectangular box shape, and the concave portion 150 is filled with the viscous fluid 54. In addition, the recessed part 150 is not limited to a rectangular box shape, Other shapes may be sufficient.

  Therefore, when the housing 112 rotates in one direction (the direction of arrow A in FIG. 14), the inclined surface 130 of the housing 112 abuts on the inclined surface 140 of the cam ring 116 so that the inclined surface 130 and the inclined surface 140 slide. It has become. For this reason, the housing 112 presses the cam ring 116 in the direction of the sliding surface 114C of the rotor 114 (in the direction of arrow B in FIG. 14). Further, when the housing 112 rotates in the other direction (the direction of arrow C in FIG. 14), the inclined surface 132 of the housing 112 comes into contact with the inclined surface 142 of the cam ring 16 so that the inclined surface 132 and the inclined surface 142 slide. It has become. For this reason, the housing 112 presses the cam ring 116 in the direction of the sliding surface 114C of the rotor 114 (in the direction of arrow B in FIG. 14).

  As a result, the clearance between the sliding surface 114C of the rotor 114 and the sliding surface 116C of the cam ring 116 when the rotor 114 and the housing 112 are relatively rotated in one direction (arrow A direction) or the other direction (arrow C direction). Is no longer changed and is kept constant (substantially 0).

  Further, in the rotary damper 110, when the viscosity (μ) of the viscous fluid 54 applied to the sliding surface between the rotor 114 and the cam ring 116 is high and the rotor 114 and the cam ring 116 rotate relatively at high speed, the viscous fluid 54 Due to this resistance, the cam ring 116 tends to be repelled from the rotor 114. That is, a repulsive force is generated that moves the cam ring 116 in a direction away from the sliding surface 114C of the rotor 114 along the rotation shaft 110A (relative rotation shaft) of the rotary damper 110. For this reason, it is conceivable that the inclination angle of the inclined surfaces 130 and 132 is reduced and the cam ring 116 can be easily moved to the rotor 114 side. However, when the inclination angle of the inclined surfaces 130 and 132 is reduced, the rotary damper 110 is used. Increases the idling angle just before the effect. Therefore, the cam ring 116 is moved in the direction of the sliding surface 114C of the rotor 114 along the rotation axis 110A of the rotary damper 110 against the repulsive force without reducing the inclination angle of the inclined surfaces 130 and 132 ( The pressing force needs to be generated by sliding between the inclined surfaces 130 and 132 of the housing 112 and the inclined surfaces 140 and 142 of the cam ring 16.

  On the other hand, in the rotary damper 110 of the present embodiment, the sliding surface 114C of the rotor 114 coated with the viscous fluid 54 and the sliding surface 116C of the cam ring 116 are inclined with respect to the rotating shaft 110A of the rotating damper 110. The sliding surface 116C of the cam ring 116 is arranged on the inner peripheral side of the sliding surface 114C of the rotor 114. Therefore, when the sliding surface to which the viscous fluid is applied is perpendicular to the rotation axis of the rotation shaft 110A of the rotary damper 110 (for example, the configuration as in the first embodiment), the housing 112 The pressing force f (= μN: N is the inclined surfaces 130 and 132 of the housing 112 and the inclined surfaces 140 and 142 of the cam ring 16 generated by sliding between the inclined surfaces 130 and 132 and the inclined surfaces 140 and 142 of the cam ring 16. The pressing force (arrow F in FIG. 13) of the present embodiment is larger (F> f) than the pressing force generated by the sliding of (F> f).

  In other words, in this embodiment, the sliding surface 114C of the rotor 114 and the sliding surface 116C of the cam ring 116 are inclined at an angle β with respect to the perpendicular H to the rotating shaft 110A of the rotating damper 110. The pressing force F to be moved toward the rotor 114 along the rotation shaft 110A of 110 is set to 1 / cos β of the pressing force f (F = μN / cos β).

(Action / Effect)
Next, the operation of this embodiment will be described.
In the rotary damper 110 of this embodiment, a rotor 114 is rotatably accommodated in a cylindrical housing 112 having a bottom portion 112A, and a cam ring 116 is rotatably provided between the housing 112 and the rotor 114. ing. In addition, inclined surfaces 130 and 132 are formed on the sliding surface 112B of the housing 112 with the cam ring 116, and the sliding surface 116B of the cam ring 116 that slides with the sliding surface 112B of the housing 112 serves as a contact portion. The inclined surfaces 140 and 142 are formed. Therefore, when the housing 112 rotates in one direction (the direction of arrow A in FIG. 12), the inclined surface 130 of the housing 112 and the inclined surface 140 of the cam ring 116 slide, and the housing 112 slides the cam ring 116 on the rotor 114. Press in the direction of the moving surface 114C (the direction of arrow B in FIG. 13). When the housing 112 rotates in the other direction (the direction of arrow C in FIG. 12), the inclined surface 132 of the housing 112 and the inclined surface 142 of the cam ring 116 slide, and the housing 112 slides the cam ring 116 on the rotor 114. Press in the direction of the surface 114C (the direction of arrow B in FIG. 13).

  As a result, when the housing 12 rotates relative to the rotor 14 in one direction (arrow A direction) or the other direction (arrow C direction), the sliding surface 114C of the rotor 114 and the sliding surface 116C of the cam ring 116 Clearance changes are eliminated and kept constant (approximately 0). For this reason, in the rotary damper 110 of the present embodiment, torque variation can be suppressed.

  In the rotary damper 110 of the present embodiment, the sliding surface 114C of the rotor 114 and the sliding surface 116C of the cam ring 116 are inclined with respect to the rotating shaft 110A of the rotary damper 110, and the sliding surface of the rotor 114 A sliding surface 116C of the cam ring 116 is disposed on the inner peripheral side of 114C. Therefore, when the sliding surface to which the viscous fluid is applied is perpendicular to the rotation axis of the rotation shaft 110A of the rotary damper 110 (for example, the configuration as in the first embodiment), the housing 112 The pressing force f (= μN: N is the inclined surfaces 130 and 132 of the housing 112 and the inclined surfaces 140 and 142 of the cam ring 16 generated by sliding between the inclined surfaces 130 and 132 and the inclined surfaces 140 and 142 of the cam ring 16. The pressing force (arrow F in FIG. 13) of the present embodiment is larger than the pressing force generated by sliding (F> f).

  In other words, in this embodiment, the sliding surface 114C of the rotor 114 and the sliding surface 116C of the cam ring 116 are inclined at an angle β with respect to the perpendicular H to the rotating shaft 110A of the rotating damper 110. The pressing force F to be moved toward the rotor 114 along the rotating shaft 110A of 110 is 1 / cos β of the pressing force f (F = μN / cos β). Therefore, if β is increased, the value of F can be increased even if N is constant.

  Therefore, in the rotary damper 110 of the present embodiment, the cam ring 116 can be prevented from being bounced from the rotor 114 even when the viscosity of the viscous fluid 54 increases. For this reason, since it is not necessary to reduce the inclination angle of the inclined surfaces 130 and 132 of the convex portion 134 of the housing 112, the rotation damper is generated when the inclination angle of the inclined surfaces 130 and 132 of the convex portion 134 of the housing 112 is reduced. It is possible to prevent an increase in the idling angle immediately before 110 is effective.

  Furthermore, in the rotary damper 110 according to the present embodiment, the sliding surface 114C of the rotor 114 and the sliding surface 116C of the cam ring 116 are inclined with respect to the rotary shaft 110A of the rotary damper 110, so The torque generation efficiency is improved. As a result, the rotary damper 110 can be reduced in size and torque. Further, it is possible to use a viscous fluid 54 having a good temperature characteristic and a high viscosity (μ).

(Other embodiments)
In the above, the present invention has been described in detail for specific embodiments. However, the present invention is not limited to the above-described embodiments, and various other embodiments are possible within the scope of the present invention. It will be apparent to those skilled in the art. For example, in the first embodiment described above, the inclined surfaces 30 and 32 are formed on the rotor 14 and the inclined surfaces 40 and 42 as contact portions are formed on the cam ring 16. However, in the first embodiment, The cam ring 16 is formed with inclined surfaces 40 and 42, and the rotor 14 is formed with inclined surfaces 30 and 32 as contact portions. Furthermore, the contact portion may be a vertical surface or the like instead of an inclined surface.

  In the second embodiment, the first inclined surface 60 and the second inclined surface 32 are formed on the rotor 14, and the inclined surface 70 as the contact portion and the inclined surface 72 are formed on the cam ring 16. However, the second embodiment has a configuration in which the first inclined surface 70 and the second inclined surface 72 are formed on the cam ring 16, and the inclined surface 60 and the inclined surface 62 as contact portions are formed on the rotor 14.

  In the third embodiment described above, the inclined surfaces 130 and 132 are formed on the housing 112, and the inclined surfaces 140 and 142 as contact portions are formed on the cam ring 116. However, in the third embodiment, The cam ring 116 is formed with inclined surfaces 140 and 142, and the housing 112 is formed with inclined surfaces 130 and 132 as contact portions. Furthermore, the contact portion may be a vertical surface or the like instead of an inclined surface.

  In the first and second embodiments, the gear 22 is formed on the outer peripheral portion of the housing 12 and the gear 26 is formed on the outer peripheral portion of the rotor 14, but the outer peripheral portion of the housing 12 or the rotor 14 is replaced with the gear. The outer peripheral portion may have a roller shape or the like.

  In the first and second embodiments, the recess 50 is formed on the sliding surface 16B of the cam ring 16, but the recess 50 may not be formed on the sliding surface 16B of the cam ring 16. Furthermore, in the first and second embodiments, the recess 50 is formed only on the sliding surface 16B of the cam ring 16, but instead, the recess 50 may be formed only on the sliding surface 12C of the housing 12. . Further, the recess 50 may be formed on both the sliding surface 16B of the cam ring 16 and the sliding surface 12C of the housing 12.

  In the third embodiment, the recess 150 is formed on the sliding surface 116C of the cam ring 116, but the recess 150 may not be formed on the sliding surface 116C of the cam ring 116. Furthermore, in the third embodiment, the recess 150 is formed only on the sliding surface 116C of the cam ring 116, but instead, the recess 150 may be formed only on the sliding surface 114C of the rotor 114. Further, the recess 150 may be formed on both the sliding surface 116C of the cam ring 116 and the sliding surface 114C of the rotor 114.

10 Rotating damper 12 Housing (first member)
12A Housing bottom 12B Housing shaft 12C Housing sliding surface 14 Rotor (second member)
14A Rotor sliding surface 16 Cam ring (sliding member)
16A Cam ring sliding surface 16B Cam ring sliding surface 22 Gear 24 Rotor circular hole 26 Gear 30 Inclined surface 32 Inclined surface 40 Inclined surface (contact portion)
42 Inclined surface (contact part)
50 concave portion 54 viscous fluid 60 first inclined surface 62 second inclined surface 70 inclined surface (contact portion)
72 Inclined surface 110 Rotary damper 112 Housing (first member)
112A Bottom of housing 112B Sliding surface of housing 112C Cylindrical portion of housing 114 Rotor (second member)
114A Rotor partition 114B Rotor shaft 114C Rotor sliding surface 116 Cam ring (sliding member)
116A Cylindrical portion of the cam ring 116B Sliding surface of the cam ring 116C Sliding surface of the cam ring 130 Inclined surface 132 Inclined surface 140 Inclined surface (contact portion)
142 Inclined surface (contact part)
150 recess

Claims (9)

A first member having a cylindrical shape having a bottom;
A second member rotatably housed in the first member;
A sliding member that is rotatably provided between the first member and the second member, and in which a viscous fluid is applied to a sliding surface that slides with the sliding surface of the first member;
A contact portion formed on one of the sliding surfaces of the second member and the sliding member;
Formed on the other of the sliding surfaces of the second member and the sliding member, the second member and the sliding member are relatively rotated by relative rotation of the first member and the second member. An inclined surface that slides against the abutting portion and presses the sliding member toward the sliding surface of the first member;
Rotating damper with. A first member having a cylindrical shape having a bottom;
A second member rotatably housed in the first member;
A sliding member that is rotatably provided between the first member and the second member, and in which a viscous fluid is applied to a sliding surface that slides with the sliding surface of the second member;
A contact portion formed on one of the sliding surfaces of the first member and the sliding member;
Formed on the other of the sliding surfaces of the first member and the sliding member, the first member and the sliding member rotate relative to each other by the relative rotation of the first member and the second member. An inclined surface that slides against the abutting portion and presses the sliding member toward the sliding surface of the second member;
Rotating damper with.   The inclined surface presses the sliding member toward the sliding surface of the first member or the second member by relative rotation in one direction between the second member or the first member and the sliding member, A pair of inclined surfaces that press the sliding member toward the sliding surface of the first member or the second member also by relative rotation in the other direction of the second member or the first member and the sliding member. The rotary damper according to claim 1 or 2.   The inclined surface is configured to press the sliding member toward the sliding surface of the first member or the second member by relative rotation in one direction between the second member or the first member and the sliding member. 1 inclined surface, in addition to the first inclined surface, sliding with the inclined surface formed in the contact portion by relative rotation of the second member or the first member and the sliding member in the other direction The rotary damper according to claim 1, further comprising a second inclined surface that pulls the sliding member back to the opposite side of the sliding surface of the first member or the second member.   5. The recess according to claim 1, wherein a concave portion for filling the viscous fluid is formed in at least one of the sliding surface of the first member or the second member and the sliding surface of the sliding member. Rotating damper.   The rotary damper according to claim 5, wherein a plurality of the recesses are arranged at a predetermined interval along a relative rotation direction of the first member or the second member and the sliding member.   The sliding surface of the said 1st member or the said 2nd member and the sliding surface of the said sliding member incline with respect to the rotating shaft of the said relative rotation. Rotating damper.   A shaft portion formed on one of the first member and the second member is inserted into a circular hole formed on the other of the first member or the second member, whereby the first member and the first member are inserted. The rotary damper according to any one of claims 1 to 7, wherein the two members are assembled.   The rotary damper according to any one of claims 1 to 8, wherein gears are formed on an outer peripheral portion of the first member and an outer peripheral portion of the second member.