Bidirectional Rotary Damper

Abstract

To provide a bidirectional rotating damper which can reduce wear by suppressing the generation of an excessive force at a contact portion between a rotating member and a stopper wall of a housing.SOLUTION: A bidirectional rotating damper comprises vanes 25A, 25B which are movably arranged at blade parts 23A. 23B, and slide integrally with the blade parts 23A, 23B, and a recessed groove 28 formed at an internal peripheral face 12a of a fluid chamber 13 of a housing 12. The vanes 25A, 25B comprise a first slide face 26A provided on a first direction side, which moves to a rotating member 14 while contacting with the internal peripheral face of the fluid chamber 13 at rotation to a first direction, and is arranged at the first direction side, and a second slide face 26B provided on a second direction side, which moves to the rotating member 14 while contacting with the internal peripheral face 12a of the fluid chamber 13 at rotation to a second direction. The recessed groove 28 is formed while having a width which is narrower than lengths of the vanes 25A, 25B in an axial direction.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a bidirectional rotary damper that applies a braking force in both directions when opening and closing, for example, a lid, a door, etc. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a bidirectional rotary damper that applies a braking force in both directions when opening and closing a lid, door, etc. is known, for example from Patent Document 1.

[0003] 9 is a schematic cross-sectional view showing an example of a conventional rotary damper 100 known from Patent Document 1. The rotary damper 100 includes a housing 101 having a fluid chamber 102 filled with a fluid and sealed therein, a rotary member 103 including a base 103a housed in the fluid chamber 102 and a shaft (not shown) protruding outside the fluid chamber 102 and rotatable relative to the housing 101, a stopper wall 104 provided in the housing 101 to limit the rotation angle of the rotary member 103 in the fluid chamber 102, and a blade 103b provided on the base 103a of the rotary member 103 to generate torque in cooperation with the stopper wall 104 during the relative rotation of the rotary member 103. The rotary damper 100 also includes one partition wall 105 and one fluid chamber 102. The fluid chamber 102 is divided into two chambers, a first fluid chamber 102A and a second fluid chamber 102B, by the blades 103b, and as the rotating member 103 rotates, the fluid moves toward the first fluid chamber 102A side and the second fluid chamber 102B side, thereby providing a braking force in both directions.

[0004] 9, when the rotating member 103 is rotated counterclockwise and the first fluid chamber 102A enters the high torque region, the pressure P presses the rotating member 103 in the 180 degree facing direction of the high torque region (the direction of the arrow 106A in the figure). Conversely, when the rotating member 103 is rotated clockwise and the second fluid chamber 102B enters the high torque region, the pressure P presses the rotating member 103 in the 180 degree facing direction of the high torque region (the direction of the arrow 106B in the figure). That is, the rotating member 103 moves (shifts) in the direction of the arrow 106A or the direction of the arrow 106B depending on the direction of rotation. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2002-295561 A Summary of the Invention [Problem to be solved by the invention]

[0006] As described above, the rotary damper 100 shown in Fig. 9, which is known from Patent Document 1 and the like, has one partition wall and a single fluid chamber 102, so that when the rotary member 103 is rotated counterclockwise and the first fluid chamber 102A enters a high torque region as shown in Fig. 9(a), the rotary member 103 is pushed by pressure in the 180 degree facing direction of the high torque region (the direction of the arrow 106A in the figure) and moves. Conversely, when the rotary member 103 is rotated clockwise and the second fluid chamber 102B enters a high torque region as shown in Fig. 9(b), the rotary member 103 is pushed by pressure in the 180 degree facing direction of the high torque region (the direction of the arrow 106B in the figure), causing the rotary member 103 to move (shift), which is a problem. This action causes the rotating member 103 to rotate eccentrically, causing the outer diameter portion of the rotating member 103 and the partition wall 105 of the housing 101 to come into strong contact with each other at the portions indicated by reference numerals 107 in Figures 9(a) and 9(b), respectively, resulting in a problem in that the excessive force causes wear to progress at the portion indicated by reference numeral 107.

[0007] Therefore, a technical problem arises that must be solved in order to provide a bidirectional rotational damper that can prevent excessive force from being generated at the contact portion between the rotating member and the stopper wall of the housing, thereby reducing wear, and the present invention aims to solve this problem. [Means for solving the problem]

[0008] The present invention has been proposed in order to achieve the above object, and the invention described in claim 1 provides a bidirectional rotation damper having a housing having a fluid chamber filled with a fluid, a rotating member having a base portion accommodated in the fluid chamber, a shaft portion protruding outside the fluid chamber, and a blade portion located in the fluid chamber, and rotatable relatively to the housing, a stopper wall provided in the housing for limiting a rotation angle of the rotating member within the fluid chamber, and torque generating means for generating torque in cooperation with the stopper wall during relative rotation of the rotating member, the torque generating means comprising: provides a bidirectional rotational damper comprising: a vane movably provided on the blade portion and sliding integrally with the blade portion; and a groove provided on an inner circumferential wall of the fluid chamber in the housing, wherein the vane has a first slide surface provided on the first direction side that contacts and slides against the inner circumferential wall of the fluid chamber when the rotating member rotates in a first direction, and a second slide surface provided on the second direction side that contacts and slides against the inner circumferential wall of the fluid chamber when the rotating member rotates in a second direction, and the groove is formed with a width smaller than the axial length of the vane.

[0009] According to this configuration, when the rotating member is rotated in a first direction, the fluid filled on the first direction side of the fluid chamber flows through the groove into the fluid chamber on the second direction side, and when the first slide surface rotates beyond the groove, the torque range enters a high torque range and braking force is applied. Conversely, when the rotating member is rotated in a second direction, the fluid filled on the second direction side of the fluid chamber flows through the groove into the fluid chamber on the first direction side, and when the second slide surface rotates beyond the groove, the torque range enters a high torque range and braking force is applied. Therefore, with this configuration, even if the rotating member rotates and enters a high torque range, the pressure is pushed back in the rotation direction opposite to the rotation of the rotating member, and the outer diameter portion of the rotating member and the stopper wall of the housing come into strong contact with each other, and wear of the outer diameter portion of the rotating member and the stopper wall of the housing that progresses due to excessive force caused by the contact can be prevented.

[0010] The invention described in claim 2 provides a bidirectional rotational damper in the configuration described in claim 1, wherein two stopper walls are provided on the inner surface of the housing to form two fluid chambers, a first fluid chamber and a second fluid chamber, which are directly opposite each other across the rotating member.

[0011] According to this configuration, by forming two fluid chambers, the first fluid chamber and the second fluid chamber, facing each other across the rotating member, the pressing forces in the fluid chambers are balanced, and the rotating member can be prevented from moving (shifting) in the horizontal direction. This further prevents wear on the outer diameter part of the rotating member and the stopper wall of the housing. That is, when the rotating member is rotated in the first direction, the fluid filled on the first direction side of the first fluid chamber flows through one of the grooves to the fluid chamber on the second direction side, and when the first slide surface rotates beyond one of the grooves, it enters a high torque range and a braking force is applied. At this time, the fluid filled on the first direction side of the second fluid chamber facing the first fluid chamber with respect to the rotating member also passes through the other groove and enters the high torque range, and a braking force is applied simultaneously with the first fluid chamber. Conversely, when the rotating member is rotated in the second direction, the fluid filled on the second direction side of the first fluid chamber flows through one of the grooves into the fluid chamber on the first direction side, and when the second slide surface rotates past one of the grooves, it enters the high torque range and a braking force is applied. Then, the fluid filled on the second direction side of the second fluid chamber also passes through the other groove and enters the high torque range, and a braking force is applied at the same time as the first fluid chamber. Therefore, with this configuration, even if the rotating member rotates and enters the high torque range, the pressure is balanced directly facing the rotating member, and the rotating member rotates without eccentricity, preventing the rotating member from moving (shifting) in the horizontal direction.

[0012] The invention described in claim 3 provides a bidirectional rotational damper in the configuration described in claim 1, wherein the rotating member is supported on the base side by a first bearing and on the shaft side by a second bearing, the housing has an opening on one end side that is closed by a cap and is provided with a bearing convex portion that supports the first bearing on the other closed end side, the first bearing has an air vent hole that penetrates from the rotating member side to the bearing convex portion side, and the cap supports the rotating member via the second bearing.

[0013] According to this configuration, the rotating member is supported on the base side by the first bearing and on the shaft side by the second bearing, and the housing and the rotating member are arranged coaxially. This allows the rotating member to rotate smoothly relative to the housing without eccentricity, and prevents wear on the rotating member, housing, and cap. In addition, the first bearing is provided with an air vent hole, which makes it easy to press the first bearing into the rotating member and maintains the accuracy of the bidirectional rotation damper.

[0014] The invention recited in claim 4 provides a bidirectional rotation damper in the configuration recited in claim 3, wherein the bearing convex portion has a relief groove formed from the tip of the bearing convex portion toward the other end side of the housing body.

[0015] According to this configuration, a relief groove is provided in the bearing convex portion from the tip of the bearing convex portion toward the other end side of the housing main body. Therefore, when assembling the bidirectional rotation damper, fluid that accumulates between the first bearing and the bearing convex portion can be guided through the relief groove to the other end side of the housing main body and then turned around the outside of the rotating member and returned to the fluid chamber side.

[0016] The invention described in claim 5 provides a bidirectional rotational damper in the configuration described in any one of claims 1 to 4, wherein the first slide surface and the second slide surface of the vane are formed approximately symmetrically on the left and right.

[0017] According to this configuration, the braking force when the rotating member is rotated in the first direction and the braking force when the rotating member is rotated in the second direction can be set to be substantially the same.

[0018] The invention described in claim 6 provides a bidirectional rotational damper, in the configuration described in any one of claims 1 to 5, wherein the vane is arranged to be swingable in the first direction and the second direction with the tip of the blade portion as a fulcrum.

[0019] According to this configuration, the vane can be fitted and connected to the tip of the blade portion of the rotating member so as to be freely swingable.

[0020] The invention described in claim 7 provides a bidirectional rotational damper in the configuration described in any one of claims 1 to 5, in which the vane has a through hole formed between the first slide surface and the second slide surface that penetrates vertically, and is formed to be slidable in the first direction and the second direction relative to the blade portion, so that when the vane is slid toward the first direction side, the fluid filled on the first direction side escapes through the through hole to the second direction side, and when the vane is slid toward the second direction side, the fluid filled on the second direction side escapes through the through hole to the first direction side.

[0021] According to this configuration, the cross-sectional shape of the connecting groove of the vane that is connected to the blade portion of the rotating member is formed into a substantially rectangular shape, and the connecting groove of the vane can be loosely fitted and connected to the blade portion of the rotating member so as to be slidable in the circumferential direction. In addition, a gap and a through hole created by the sliding movement in the circumferential direction can be used to form a flow path for the fluid. Effect of the Invention

[0022] According to the present invention, even if the rotating member rotates and enters a high torque range, the pressure is pushed back in the direction opposite to the rotation of the rotating member, and the rotating member is not pressed 180 degrees opposite to the high torque range, so it is possible to prevent the rotating member from moving (shifting) in the horizontal direction. Therefore, it is possible to prevent the outer diameter part of the rotating member and the stopper wall of the housing from coming into strong contact with each other, and wear of the outer diameter part of the rotating member and the stopper wall of the housing that progresses due to excessive force caused by the contact, and the life of each part can be extended. [Brief description of the drawings]

[0023] [Figure 1] 1A shows a bidirectional rotation damper according to a first embodiment of the present invention, where (a) is a front view, (b) is a cross-sectional view taken along line AA in (a), and (c) is a cross-sectional view taken along line BB in (b). [Diagram 2] FIG. 2 is an exploded perspective view of the bidirectional rotary damper according to the first embodiment of the present invention. [Diagram 3]1A shows a vane in a bidirectional rotary damper according to the first embodiment of the present invention, with (a) being an external perspective view as viewed from the outer periphery side, (b) being an external perspective view as viewed from the inner periphery side, (c) being a plan view as viewed from the outer periphery side, (d) being a plan view as viewed from the inner periphery side, (e) being a side view as viewed from the direction of arrow X in (a), (f) being a side view as viewed from the direction of arrow Y in (a), (g) being a cross-sectional view taken along line CC in (e), and (h) being a cross-sectional view taken along line DD in (f). [Figure 4] 4A to 4C are diagrams illustrating the operation of the bidirectional rotary damper in the first embodiment. [Diagram 5] 5A shows a bidirectional rotation damper according to a second embodiment of the present invention, where (a) is a front view, (b) is a cross-sectional view taken along line EE in (a), and (c) is a cross-sectional view taken along line FF in (b). [Figure 6] FIG. 11 is an exploded perspective view of the bidirectional rotary damper according to the second embodiment of the present invention. [Figure 7] 10A is an external perspective view of a vane in a bidirectional rotary damper according to the second embodiment of the present invention, where (a) is an external perspective view seen from the outer periphery side, (b) is an external perspective view seen from the inner periphery side, (c) is a plan view seen from the outer periphery side, (d) is a plan view seen from the inner periphery side, (e) is a side view seen from the direction of arrow X in (a), (f) is a side view seen from the direction of arrow Y in (a), (g) is a cross-sectional view taken along line GG in (e), and (h) is a cross-sectional view taken along line HH in (f). [Figure 8] 11 is an explanatory diagram of the operation of the bidirectional rotary damper in the second embodiment. FIG. [Figure 9] 1A and 1B are schematic cross-sectional views showing an example of a conventional bidirectional rotation damper, in which (a) is a diagram explaining the action when a rotating member is rotated from a neutral position to an end in the counterclockwise direction, and (b) is a diagram explaining the action when the rotating member is rotated from a neutral position to an end in the clockwise direction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] In order to achieve the object of providing a bidirectional rotation damper capable of reducing wear by suppressing the generation of excessive force at the contact portion between a rotating member and a stopper wall of a housing, the present invention provides a bidirectional rotation damper having a housing having a fluid chamber filled with a fluid, a rotating member having a base portion housed in the fluid chamber, a shaft portion protruding outside the fluid chamber, and a blade portion located in the fluid chamber and rotatable relatively to the housing, a stopper wall provided in the housing for limiting the rotation angle of the rotating member in the fluid chamber, and torque generating means for generating torque in cooperation with the stopper wall during relative rotation of the rotating member. In the rolling damper, the torque generating means comprises a vane that is movably provided on the blade portion and slides integrally with the blade portion, and a groove provided in the inner wall of the fluid chamber in the housing, the vane having a first slide surface provided on the first direction side that contacts and slides against the inner wall of the fluid chamber when the rotating member rotates in a first direction, and a second slide surface provided on the second direction side that contacts and slides against the inner wall of the fluid chamber when the rotating member rotates in a second direction, and the groove is formed with a width smaller than the axial length of the vane. EXAMPLES

[0025] An embodiment of the present invention will be described in detail below with reference to the accompanying drawings. In the following embodiment, when the number, value, amount, range, etc. of components are mentioned, the number is not limited to the specific number, and may be more or less than the specific number, unless otherwise specified or when it is clearly limited to a specific number in principle.

[0026] In addition, when referring to the shape or positional relationship of components, etc., this includes things that are substantially similar or approximate to those shapes, etc., unless otherwise specified or considered to be clearly different in principle.

[0027] In addition, the drawings may exaggerate characteristic parts to make the features easier to understand, and the dimensional ratios of the components may not be the same as the actual ones. In addition, in cross-sectional views, hatching of some components may be omitted to make the cross-sectional structure of the components easier to understand.

[0028] In the following description, the expressions indicating directions such as up, down, left, right, etc. are not absolute, but are appropriate when each part of the bidirectional rotation damper of the present invention is in the posture depicted, but if the posture is changed, the interpretation should be changed according to the change in posture. Also, the same elements are given the same symbols throughout the description of the embodiments.

[0029] 1 and 2 show a bidirectional rotation damper 10A according to a first embodiment of the present invention, with (a) in Fig. 1 being a front view, (b) being a cross-sectional view taken along line AA in (a), (c) being a cross-sectional view taken along line BB in (b), and Fig. 2 being an exploded perspective view of the bidirectional rotation damper 10A. In the following description, the left side in Fig. 1(b) will be referred to as the front side in the longitudinal direction of the bidirectional rotation damper 10A, and the right side as the rear side.

[0030] 1 and 2, the bidirectional rotation damper 10A has a structure in which a base 14A of a rotating member 14 is incorporated within a fluid chamber 13 of a housing 12 which is filled and sealed with a fluid 11 such as highly viscous silicone oil, and a shaft portion 14B of the rotating member 14 protrudes outside the fluid chamber 13.

[0031] The housing 12 is made of die-casting, and one end 12A of the housing 12 (hereinafter referred to as the "closed end 12A") is closed and forms one side wall of the fluid chamber 13. A bearing protrusion 15 is formed in the center of the closed end 12A on the fluid chamber 13 side. The other end 12B of the housing 12 (hereinafter referred to as the "open end 12B") is opened and is closed in a sealed state by fitting and fixing an annular die-cast end cap 18 through a resin annular pressure bulkhead plate 16 that forms the other side wall of the fluid chamber 13 and rubber O-rings 17A and 17B that are sealing members. The end cap 18 and the open end 12B are fitted and fixed by a male thread formed on the outer periphery of the end cap 18 and a female thread formed on the inner periphery of the open end 12B.

[0032] The base 14A of the rotating member 14 is journaled on the bearing protrusion 15 of the housing 12 via a first bearing 20 consisting of a bush inserted into a recess 19 provided at one end of the base 14A, and the shaft portion 14B is journaled on the end cap 18 via a second bearing 21 consisting of a bush that penetrates the center of the pressure bulkhead plate 16 and the end cap 18 and is interposed between the end cap 18 and the shaft portion 14B. The rotating member 14 is journaled on the first bearing 20 and the second bearing 21, so that it is disposed rotatable relative to the housing 12.

[0033] The fluid chamber 13 of the housing 12 is provided with two stopper walls 22 that protrude from the inner peripheral surface 12a of the housing 12 toward the center, and the two stopper walls 22 divide the fluid chamber 13 into a first fluid chamber 13A and a second fluid chamber 13B. The two stopper walls 22 are provided at approximately 180 degrees offset from each other in the circumferential direction, and the protrusions of each stopper wall 22 extend to a position where they are in contact with the outer peripheral surface of the base 14A. Therefore, the first fluid chamber 13A and the second fluid chamber 13B are provided at approximately 180 degrees offset from each other in the circumferential direction.

[0034] The stopper wall 22 has both the function of limiting the rotation angle of the rotating member 14 and the function of generating torque. A first blade portion 23A and a second blade portion 23B are provided on a part of the outer circumferential surface of the base portion 14A of the rotating member 14, which are convex along the axial direction of the rotating member 14, at positions displaced from each other by approximately 180 degrees in the circumferential direction. In addition, a first vane 25A and a second vane 25B constituting a torque generating means for generating torque in cooperation with the stopper wall 22 are attached to the tip portions of the first blade portion 23A and the second blade portion 23B, respectively, so as to be swingable in the circumferential direction of the rotating member 14.

[0035] The tip of first blade portion 23A and the tip of second blade portion 23B have a circular cross section, and connecting portion 24A between first vane 25A and second vane 25B has a groove with a C-shaped cross section. Connecting portion 24A is provided in the approximate center of first vane 25A and second vane 25B in the rotational direction, corresponding to the tip of first blade portion 23A and the tip of second blade portion 23B, respectively. The tip of the first blade portion 23A and the first vane 25A, and the tip of the second blade portion 23B and the second vane 25B are connected to each other so as to be swingable (or rotatable) in the circumferential direction of the rotating member 14 by fitting each tip of the first blade portion 23A and the second blade portion 23B, which have a circular cross section, into the connecting portion 24A having a C-shaped cross section, and the first vane 25A and the second vane 25B after connection are mounted so as to be swingable back and forth in the circumferential direction of the rotating member 14, with each tip of the first blade portion 23A and the second blade portion 23B as a fulcrum. After mounting, the first vane 25A and the second vane 25B move along the inner circumferential surface 12a of the housing 12 with which they are integrated in the same direction as the rotating member 14 when the rotating member 14 is rotated.

[0036] The first vane 25A and the second vane 25B have substantially the same structure. The first vane 25A and the second vane 25B are also shown as single components in FIG. 3. To further explain with reference to FIG. 3, the first vane 25A and the second vane 25B are provided with a first slide surface 26A and a second slide surface 26B, respectively, on the outer surface side facing the inner peripheral surface 12a of the housing 12 and on both sides in the rotation direction of the rotating member 14 across the connecting portion 24A, in a substantially symmetrical manner. In addition, the front and rear portions of the first slide surface 26A and the second slide surface 26B are formed with portions recessed inward from the first slide surface 26A and the second slide surface 26B, i.e., recesses 27. When the rotating member 14 rotates in a first direction (clockwise direction), the first vane 25A and the second vane 25B rotate in a second direction (counterclockwise direction) with the tip of the first blade portion 23A and the tip of the second blade portion 23B as fulcrums, respectively, and the second slide surface 26B moves away from the inner surface 12a of the housing 12, and the first slide surface 26A slides in the first direction while contacting the inner surface 12a of the housing 12. Conversely, when the rotating member 14 rotates in the second direction (counterclockwise direction), the first vane 25A and the second vane 25B rotate in the first direction (clockwise direction) with the tip of the first blade portion 23A and the tip of the second blade portion 23B as fulcrums, respectively, so that the first sliding surface 26A moves away from the inner surface 12a of the housing 12 and the second sliding surface 26B slides in the second direction while contacting the inner surface 12a of the housing 12.

[0037] Further, in the inner circumferential surface 12a forming the fluid chamber 13 of the housing 12, recessed grooves 28 are provided corresponding to the first fluid chamber 13A and the second fluid chamber 13B, respectively. The axial width of the recessed groove 28 is formed slightly smaller than the axial width of the first vane 25A and the second vane 25B, as shown in Fig. 1(b). Furthermore, both ends of the recessed groove 28 in the circumferential direction are extended to positions slightly corresponding to the recessed portion 27 when the first vane 25A and the second vane 25B are disposed as shown in Fig. 4(a) and Fig. 4(c) described later, in which the rotation of the first vane 25A and the second vane 25B is limited by the stopper wall 22, so that the fluid 11 in the high torque region can escape to the low torque region side through the recessed groove 28.

[0038] The first bearing 20 is provided with an air vent hole 29 penetrating from the rotating member 14 side to the bearing protrusion 15 side, and the outer peripheral surface of the bearing protrusion 15 is provided with a relief groove 30 formed continuously from the tip of the bearing protrusion 15 toward the other end side of the housing 12, that is, from the tip of the bearing protrusion 15 to the inner surface of the closed end 12A. The air vent hole 29 allows air that has entered between the first bearing 20 and the rotating member 14 to be released through the air vent hole 29, thereby facilitating the press-fitting of the first bearing 20 into the rotating member 14 and maintaining the accuracy of the bidirectional rotary damper 10A. On the other hand, the relief groove 30 guides the fluid 11 that has entered and accumulated between the first bearing 20 and the bearing protrusion 15 through the relief groove 30 to the other end side (closed end 12A side) of the housing 12, and then turns it around the outside of the rotating member 14 to return it to the fluid chamber 13 side.

[0039] 4 is a diagram showing the operation of the bidirectional rotary damper 10 A. Next, the operation of the bidirectional rotary damper 10 A will be described with reference to FIG.

[0040] In (a) of Figure 4, when the rotating member 14 rotates in a first direction (clockwise direction) indicated by arrow 51A, the pressure-receiving surfaces 31 of the first vane 25A and the second vane 25B are subjected to resistance by the viscous fluid 11 in the fluid chamber 13, and the first vane 25A and the second vane 25B rotate in the counterclockwise direction indicated by arrow 52A with the tips of the first blade portion 23A and the second blade portion 23B as fulcrums, respectively, and the first slide surface 26A contacts the inner surfaces 12a of the first fluid chamber 13A and the second fluid chamber 13B, respectively. Since the first slide surface 26A and the second slide surface 26B of the first vane 25A and the second vane 25B are formed with recesses 27 as fluid passages, the fluid 11 present on the clockwise side in the first fluid chamber 13A and the second fluid chamber 13B flows counterclockwise through the recessed groove 28 and the recessed portion 27, as shown by the dotted line 11A in Fig. 4(a). This allows the rotating member 14 and the housing 12 to rotate relatively with low torque.

[0041] Furthermore, as the rotation of the rotating member 14 progresses, the first slide surface 26A reaches the end of the recessed groove 28 provided in the inner circumferential surface 12a of the housing 12, and the first slide surface 26A comes into contact with the inner circumferential surfaces 12a of the first fluid chamber 13A and the second fluid chamber 13B, respectively, as shown in Fig. 4(b). Up to the state shown in Fig. 4(b), the fluid 11 on the clockwise side in the first fluid chamber 13A and the second fluid chamber 13B is in a low torque region where it flows counterclockwise through the recessed groove 28 and the recess 27, and the rotating member 14 and the housing 12 can be rotated relative to each other with low torque. However, when the first slide surface 26A contacts the inner circumferential surface 12a of the first fluid chamber 13A and the second fluid chamber 13B beyond the portion where the recessed groove 28 is provided, the fluid 11 flows little by little in the counterclockwise direction through the gap between the inner circumferential surface 12a of the housing 12 and the first vane 25A and the second vane 25B, and through the gap between the first blade portion 23A and the second blade portion 23B and the first vane 25A and the second vane 25B. As a result, the rotating member 14 and the housing 12 enter a high torque region and rotate slowly relative to each other. This slow relative rotation continues until the first vane 25A and the second vane 25B collide with the stopper wall 22 and the rotation is restricted. FIG. 4(c) shows the state of the high torque region.

[0042] The above is the operation when the rotating member 14 is rotated in the first direction (clockwise direction) indicated by the arrow 51A. Next, the operation when the rotating member 14 is rotated from the state where it is stopped at the first direction end shown in FIG. 4(c) to the second direction (counterclockwise direction) end will be described.

[0043] 4(d), when the rotating member 14 rotates in the second direction (counterclockwise direction) indicated by the arrow 51B, the pressure receiving surface 31 of the first vane 25A and the second vane 25B receives resistance from the fluid 11, and the first vane 25A and the second vane 25B rotate in the clockwise direction indicated by the arrow 52B with the tip of the first blade portion 23A and the second blade portion 23B as a fulcrum, respectively, and the second slide surface 26B contacts the inner circumferential surface 12a of the first fluid chamber 13A and the second fluid chamber 13B, respectively. Since the first slide surface 26A and the second slide surface 26B of the first vane 25A and the second vane 25B are formed with the recess 27 as a fluid passage, the fluid 11 on the counterclockwise side in the first fluid chamber 13A and the second fluid chamber 13B flows to the clockwise side through the recess groove 28 and the recess 27. This allows the rotating member 14 and the housing 12 to rotate relative to each other with low torque.

[0044] Furthermore, as the rotation of the rotating member 14 progresses, the first slide surface 26A reaches the end of the recessed groove 28 provided in the inner circumferential surface 12a of the housing 12, and the second slide surface 26B comes into contact with the inner circumferential surfaces 12a of the first fluid chamber 13A and the second fluid chamber 13B, respectively, as shown in Fig. 4(e). Up to the state shown in Fig. 4(e), the fluid 11 on the counterclockwise side in the first fluid chamber 13A and the second fluid chamber 13B is in a low torque region where it flows clockwise through the recessed groove 28 and the recess 27, and the rotating member 14 and the housing 12 can be rotated relative to each other with low torque. However, when the second slide surface 26B contacts the inner circumferential surface 12a of the first fluid chamber 13A and the second fluid chamber 13B beyond the portion where the recessed groove 28 is provided, the fluid 11 flows little by little in the clockwise direction through the gap between the inner circumferential surface 12a of the housing 12 and the first vane 25A and the second vane 25B, and through the gap between the first blade portion 23A and the second blade portion 23B and the first vane 25A and the second vane 25B. As a result, the rotating member 14 and the housing 12 enter a high torque region and rotate slowly relative to each other. This slow relative rotation continues until the first vane 25A and the second vane 25B collide with the stopper wall 22 and the rotation is restricted. FIG. 4(f) shows the state of the high torque region.

[0045] Therefore, in the bidirectional rotating damper 10A shown in the first embodiment, whether it rotates in the first direction (clockwise) or the second direction (counterclockwise), it can rotate smoothly with low torque before reaching the end, and as it approaches the end, it can rotate slowly with high torque. Therefore, if this bidirectional rotating damper 10A is applied to an opening and closing mechanism for a lid door, it can apply a braking force in both directions during opening and closing, so that it can close slowly at the closing end to prevent accidents such as finger pinching.

[0046] Also, when the rotating member 14 is rotated in the first direction, the fluid 11 filled in the first direction side of the fluid chamber 13 flows through the recess 27 and the recessed groove 28 into the fluid chamber 13 on the second direction side, and when the first slide surface 26A is rotated beyond the recessed groove 28, the high torque region is entered, and a braking force is applied. Conversely, when the rotating member 14 is rotated in the second direction, the fluid 11 filled in the second direction side of the fluid chamber 13 flows through the recess 27 and the recessed groove 28 into the fluid chamber 13 on the first direction side, and when the second slide surface 26B is rotated beyond the recessed groove 28, the high torque region is entered, and a braking force is applied. Therefore, in this configuration, even if the rotating member 14 rotates and enters the high torque region, the pressure is balanced with the rotating member 14 as the center, and the rotating member 14 rotates without eccentricity, and the rotating member 14 can be prevented from moving (shifting) in the horizontal direction. This can prevent the base 14A of the rotating member 14 and the stopper wall 22 of the housing 12 from coming into strong contact with each other. In other words, wear caused by strong contact between the base portion 14A of the rotating member 14 and the stopper wall 22 of the housing 12 can be prevented.

[0047] 5 and 6 show a bidirectional rotary damper 10B according to a second embodiment of the present invention, in which (a) of FIG. 5 is a front view, (b) is a cross-sectional view along the line EE in (a), (c) is a cross-sectional view along the line FF in (b), and FIG. 6 is an exploded perspective view of the bidirectional rotary damper 10B. In the following description, the left side in the left-right direction in (b) of FIG. 5 is the front in the front-rear direction of the bidirectional rotary damper, and the right side is the rear. The bidirectional rotary damper 10B of the second embodiment shown in FIG. 5 and FIG. 6 is a modified version of the first blade portion 23A and the second blade portion 23B and the first vane 25A and the second vane 25B of the base portion 14A in the bidirectional rotary damper 10A of the first embodiment shown in FIG. 1 to FIG. 4, and the other structures are substantially the same and perform the same functions. Therefore, the same members as those of the bidirectional rotary damper 10A of the first embodiment shown in FIG. 1 to FIG. 4 are given the same reference numerals and some of the descriptions are omitted.

[0048] 5 and 6, the bidirectional rotation damper 10B has a structure in which a base 14A of a rotating member 14 is incorporated within a fluid chamber 13 of a housing 12 in which a fluid 11 such as highly viscous silicone oil is filled and sealed, and a shaft portion 14B of the rotating member 14 protrudes outside the fluid chamber 13.

[0049] The housing 12 is made of die-casting, and one end 12A of the housing 12 (hereinafter referred to as the "closed end 12A") is closed and forms one side wall of the fluid chamber 13. A bearing protrusion 15 is formed in the center of the closed end 12A on the fluid chamber 13 side. The other end 12B of the housing 12 (hereinafter referred to as the "open end 12B") is opened and is closed in a sealed state by fitting and fixing an annular die-cast end cap 18 through a resin annular pressure bulkhead plate 16 that forms the other side wall of the fluid chamber 13 and rubber O-rings 17A and 17B that are sealing members. The end cap 18 and the open end 12B are fitted and fixed by a male thread formed on the outer periphery of the end cap 18 and a female thread formed on the inner periphery of the open end 12B.

[0050] The base 14A of the rotating member 14 is journaled on the bearing protrusion 15 of the housing 12 via a first bearing 20 consisting of a bush inserted into a recess 19 provided at one end of the base 14A, and the shaft portion 14B is journaled on the end cap 18 via a second bearing 21 consisting of a bush that penetrates the center of the pressure bulkhead plate 16 and the end cap 18 and is interposed between the end cap 18 and the shaft portion 14B. The rotating member 14 is journaled on the first bearing 20 and the second bearing 21, so that it is disposed rotatable relative to the housing 12.

[0051] The fluid chamber 13 of the housing 12 is divided into a first fluid chamber 13A and a second fluid chamber 13B by two stopper walls 22 formed to protrude from the inner peripheral surface 12a of the housing 12 toward the center. The two stopper walls 22 are provided at approximately 180 degrees offset from each other in the circumferential direction, and the protrusions of each stopper wall 22 extend to a position where they are in contact with the outer peripheral surface of the base 14A. Therefore, the first fluid chamber 13A and the second fluid chamber 13B are provided at approximately 180 degrees offset from each other in the circumferential direction.

[0052] The stopper wall 22 has both the function of limiting the rotation angle of the rotating member 14 and the function of generating torque. A first blade portion 23C and a second blade portion 23D, which are convex along the axial direction of the rotating member 14, are provided on a part of the outer circumferential surface of the base portion 14A of the rotating member 14 at positions displaced from each other by approximately 180 degrees in the circumferential direction. In addition, a first vane 25C and a second vane 25D, which constitute a torque generating means that generates torque in cooperation with the stopper wall 22, are attached to the tip portions of the first blade portion 23C and the second blade portion 23D, respectively, so as to be slidable by a limited amount in the circumferential direction of the rotating member 14.

[0053] The tip of the first blade 23C and the tip of the second blade 23D have a rectangular cross section, and the connecting portion 24B between the first vane 25C and the second vane 25D has a groove with a rectangular cross section. The connecting portion 24B is provided in the approximate center of the first vane 25C and the second vane 25D in the rotation direction, corresponding to the tip of the first blade 23C and the tip of the second blade 23D, respectively. The tip of the first blade 23C and the first vane 25C, and the tip of the second blade 23D and the second vane 25D are connected to be slidable by a limited amount in the circumferential direction of the rotating member 14 by loosely fitting the tips of the first blade 23C and the second blade 23D, each of which has a rectangular cross section, into the connecting portion 24B, which forms a rectangular cross section groove. That is, the circumferential groove width of the connecting portion 24B is formed larger than the circumferential width of each tip of the first blade portion 23C and the second blade portion 23D, and the first vane 25C and the second vane 25D can slide in the circumferential direction relative to the first blade portion 23C and the second blade portion 23D by the difference between the groove width and the circumferential width of the tip. In addition, the tip of the first blade portion 23C and the tip of the second blade portion 23D are each provided with a notch 33 that is removed from the tip surface toward the base portion 14A. The notch 33 functions as a flow path for the fluid 11.

[0054] The first vane 25C and the second vane 25D have substantially the same structure. The first vane 25C and the second vane 25D are also shown as single parts in FIG. 7. To further explain with reference to FIG. 7, the first vane 25C and the second vane 25D are provided with the first slide surface 26C and the second slide surface 26D, respectively, on the outer surface side facing the inner peripheral surface 12a of the housing 12 and on both sides in the rotation direction of the rotating member 14 across the connecting portion 24B, in a substantially symmetrical manner. In addition, the front and rear portions of the first slide surface 26C and the second slide surface 26D are formed with recesses 27, i.e., portions recessed inward from the first slide surface 26C and the second slide surface 26D. In addition, a through hole 32 that functions as a flow path for the fluid 11 and penetrates to the connecting portion 24B is provided at the substantially central portion of the recess 27.

[0055] When the rotating member 14 rotates in the first direction (clockwise direction), the first slide surface 26C and the second slide surface 26D slide and move the first vane 25C and the second vane 25D in the second direction (counterclockwise direction) relative to the tip of the first blade portion 23C and the tip of the second blade portion 23D, causing a gap to form between the side of the tip of the first blade portion 23C and the second blade portion 23D on the second direction side and the inner surface of the first vane 25C and the second vane 25D on the second direction side, forming a passage through which the fluid 11 flows toward the second direction side (counterclockwise direction) through the gap between the recess 27, the through hole 32, the cutout portion 33, and the base 14A. Conversely, when the rotating member 14 rotates in the second direction (counterclockwise direction), the first vane 25C and the second vane 25D slide in the first direction (clockwise direction) relative to the tip of the first blade portion 23C and the tip of the second blade portion 23D, causing a gap to form between the side of the tip of the first blade portion 23C and the second blade portion 23D on the first direction side and the inner surface of the first vane 25C and the second vane 25D on the first direction side, forming a passage through which the fluid 11 flows toward the first direction side through the gap between the recess 27, the through hole 32, the cutout portion 33, and the base 14A.

[0056] Further, in the inner circumferential surface 12a forming the fluid chamber 13 of the housing 12, recessed grooves 28 are provided corresponding to the first fluid chamber 13A and the second fluid chamber 13B, respectively. The axial width of the recessed groove 28 is formed slightly smaller than the axial width of the first vane 25C and the second vane 25D, as shown in Fig. 5(b). Furthermore, both ends of the recessed groove 28 in the circumferential direction are extended to positions slightly corresponding to the recessed portion 27 when the first vane 25C and the second vane 25D are disposed as shown in Fig. 8(a) and Fig. 8(c) described later, in which the rotation of the first vane 25C and the second vane 25D is limited by the stopper wall 22, so that the fluid 11 in the high torque region can escape to the low torque region side through the recessed groove 28.

[0057] The first bearing 20 is provided with an air vent hole 29 penetrating from the rotating member 14 side to the bearing protrusion 15 side, and the outer peripheral surface of the bearing protrusion 15 is provided with a relief groove 30 formed continuously from the tip of the bearing protrusion 15 toward the other end side of the housing 12, that is, from the tip of the bearing protrusion 15 to the inner surface of the closed end 12A. The air vent hole 29 allows air that has entered between the first bearing 20 and the rotating member 14 to be released through the air vent hole 29, thereby facilitating the press-fitting of the first bearing 20 into the rotating member 14 and maintaining the accuracy of the bidirectional rotary damper 10B. On the other hand, the relief groove 30 guides the fluid 11 that has entered and accumulated between the first bearing 20 and the bearing protrusion 15 through the relief groove 30 to the other end side (closed end 12A side) of the housing 12, and then turns it around the outside of the rotating member 14 to return it to the fluid chamber 13 side.

[0058] 8 is a diagram showing the operation of the bidirectional rotary damper 10B. Next, the operation of the bidirectional rotary damper 10B will be described with reference to FIG.

[0059] In (a) of Figure 8, when the rotating member 14 rotates in the first direction (clockwise direction) indicated by arrow 51A, the pressure-receiving surfaces 31 of the first vane 25C and the second vane 25D are resisted by the viscous fluid 11 in the fluid chamber 13, and the first vane 25C and the second vane 25D slide in the second direction (counterclockwise direction) relative to the tips of the first blade portion 23C and the second blade portion 23D, respectively, causing a gap to form between the side faces of the tips on the second direction side of the first blade portion 23C and the second blade portion 23D and the inner faces on the second direction side of the first vane 25C and the second vane 25D, and the fluid 11 creates gaps between the recess 27, the through hole 32, the cutout portion 33, and the base 14A. In addition, the first and second slide surfaces 26C and 26D of the first and second vanes 25C and 25D are formed with recesses 27 as fluid passages, so that the fluid 11 present in the clockwise direction in the first and second fluid chambers 13A and 13B flows from the recess grooves 28 into the recesses 27, as shown by the dotted lines 11A in Fig. 8(a), and further flows through the through holes 32, the notches 33, and the gaps between the base 14A toward the second direction (counterclockwise direction). This allows the rotating member 14 and the housing 12 to rotate relatively with low torque.

[0060] Furthermore, as the rotation of the rotating member 14 progresses, the first slide surface 26C reaches the end of the recessed groove 28 provided in the inner circumferential surface 12a of the housing 12, and as shown in Fig. 8(b), the first slide surface 26C comes into contact with the inner circumferential surfaces 12a of the first fluid chamber 13A and the second fluid chamber 13B, respectively. Up to the state shown in Fig. 8(b), the fluid 11 on the clockwise side in the first fluid chamber 13A and the second fluid chamber 13B is in a low torque region where it flows counterclockwise through the recessed groove 28 and the recess 27, and the rotating member 14 and the housing 12 can be rotated relative to each other with low torque. However, when the first slide surface 26C contacts the inner circumferential surface 12a of the first fluid chamber 13A and the second fluid chamber 13B beyond the portion where the recessed groove 28 is provided, the fluid 11 flows little by little in the counterclockwise direction through the gap between the inner circumferential surface 12a of the housing 12 and the first vane 25C and the second vane 25D, the gap between the first blade portion 23C and the second blade portion 23D and the first vane 25A and the second vane 25B, the notch portion 33, and the through hole 32. As a result, the rotating member 14 and the housing 12 enter a high torque region and rotate slowly relative to each other. This slow relative rotation continues until the first vane 25C and the second vane 25D collide with the stopper wall 22 and the rotation is restricted. FIG. 8(c) shows the state of the high torque region.

[0061] The above is the operation when the rotating member 14 is rotated in the first direction (clockwise direction) indicated by the arrow 51A. Next, the operation when the rotating member 14 is rotated from the state where it is stopped at the first direction end shown in FIG. 8(c) to the second direction end (counterclockwise direction) will be described.

[0062] In (d) of Figure 8, when the rotating member 14 rotates in the second direction (counterclockwise direction) indicated by arrow 51B, the pressure-receiving surfaces 31 of the first vane 25C and the second vane 25D are resisted by the viscous fluid 11 in the fluid chamber 13, and the first vane 25C and the second vane 25D slide in the first direction (clockwise direction) relative to the tips of the first blade portion 23C and the second blade portion 23D, respectively, causing a gap to form between the side of the tip portion on the second direction side of each of the first blade portion 23C and the second blade portion 23D and the inner surface on the first direction side of each of the first vane 25C and the second vane 25D, and creating a gap between the recess 27, the through hole 32, the cutout portion 33, and the base 14A through which the fluid 11 can pass. In addition, the first and second slide surfaces 26C and 26D of the first and second vanes 25C and 25D are formed with recesses 27 as fluid passages, so that the fluid 11 present on the clockwise side in the first and second fluid chambers 13A and 13B flows from the recessed grooves 28 into the recesses 27, as shown by the dotted lines 11A in Fig. 8(d), and further flows toward the first direction (clockwise direction) through the through holes 32, the notches 33, and the gaps between the base 14A. This allows the rotating member 14 and the housing 12 to rotate relatively with low torque.

[0063] Furthermore, as the rotation of the rotating member 14 progresses, the second slide surface 26D reaches the end of the recessed groove 28 provided in the inner circumferential surface 12a of the housing 12, and as shown in Fig. 8(e), the second slide surface 26D comes into contact with the inner circumferential surfaces 12a of the first fluid chamber 13A and the second fluid chamber 13B, respectively. Up to the state shown in Fig. 8(e), the fluid 11 on the counterclockwise side in the first fluid chamber 13A and the second fluid chamber 13B is in a low torque region where it flows clockwise through the recessed groove 28 and the recess 27, and the rotating member 14 and the housing 12 can be rotated relative to each other with low torque. However, when the second slide surface 26D contacts the inner circumferential surface 12a of the first fluid chamber 13A and the second fluid chamber 13B beyond the portion where the recessed groove 28 is provided, the fluid 11 flows little by little in the clockwise direction through the gap between the inner circumferential surface 12a of the housing 12 and the first vane 25C and the second vane 25D, the gap between the first blade portion 23C and the second blade portion 23D and the first vane 25C and the second vane 25D, the notch portion 33, and the through hole 32. As a result, the rotating member 14 and the housing 12 enter a high torque region and rotate slowly relative to each other. This slow relative rotation continues until the first vane 25C and the second vane 25D collide with the stopper wall 22 and the rotation is restricted. FIG. 8(f) shows the state of the high torque region.

[0064] Therefore, even in the bidirectional rotating damper 10B shown as the second embodiment, whether it rotates in the first direction (clockwise) or the second direction (counterclockwise), it can rotate smoothly with low torque before reaching the end, and as it approaches the end, it can rotate slowly with high torque. Therefore, if this bidirectional rotating damper 10B is applied to the opening and closing mechanism of the lid door, it can apply a braking force in both directions during opening and closing, so that it can close slowly at the closing end to prevent accidents such as finger pinching.

[0065] Also, when the rotating member 14 is rotated in the first direction, the fluid 11 filled in the first direction side of the fluid chamber 13 flows through the recess 27 and the recessed groove 28 into the fluid chamber 13 on the second direction side, and when the first slide surface 26C is rotated beyond the recessed groove 28, the high torque region is entered, and a braking force is applied. Conversely, when the rotating member 14 is rotated in the second direction, the fluid 11 filled in the second direction side of the fluid chamber 13 flows through the recess 27 and the recessed groove 28 into the fluid chamber 13 on the first direction side, and when the second slide surface 26D is rotated beyond the recessed groove 28, the high torque region is entered, and a braking force is applied. Therefore, in this configuration, even if the rotating member 14 rotates and enters the high torque region, the pressure is balanced with the rotating member 14 as the center, and the rotating member 14 rotates without eccentricity, and the rotating member 14 can be prevented from moving (shifting) in the horizontal direction. This can prevent the base 14A of the rotating member 14 from coming into strong contact with the stopper wall 22 of the housing 12. In other words, wear caused by strong contact between the base portion 14A of the rotating member 14 and the stopper wall 22 of the housing 12 can be prevented.

[0066] In each embodiment, the positions of the high torque region and the low torque region with respect to the rotation angle of the rotating member 14 can be changed by adjusting the relative positions of the recessed groove 28 and the recessed portion 27, etc.

[0067] Furthermore, the present invention can be modified in various ways without departing from the spirit of the present invention, and it is natural that the present invention covers such modifications. [Explanation of symbols]

[0068] 10A: Bidirectional rotary damper 10B: Bidirectional rotary damper 11:Fluid 11A: Fluid flow 12: Housing 12A: Closed end 12B: Open end 12a: Inner surface 13:Fluid chamber 13A: 1st fluid chamber 13B: 2nd fluid chamber 14: Rotating member 14A: Base 14B:Shaft part 15: Bearing protrusion 16: Pressure bulkhead plate 17A: O-ring 17B: O-ring 18: End cap 19: Recess 20: First bearing 21: Second bearing 22: Stopper wall 23A: First blade 23B: Second wing part 23C: First blade 23D: Second blade 24A: Connection part 24B:Connection part 25A: First vane 25B: 2nd vane 25C: 1st vane 25D: 2nd vane 26A: First slide surface 26B: Second slide surface 26C: First slide surface 26D: Second slide surface 27: Recess 28: Groove 29: Air vent hole 30: Relief groove 31: Pressure receiving surface 32:Through hole 33: Notch 51A: Arrow 51B: Arrow 52A: Arrow 52B: Arrow 100: Rotating damper 101: Housing 102:Fluid chamber 102A: 1st fluid chamber 102B:Second fluid chamber 103: Rotating member 103a: Base 103b: Feather 104: Stopper wall 105: Bulkhead 106A: Arrow 106B: Arrow P: Pressure X : Arrow Y : Arrow

Claims

1. a housing having a fluid chamber filled with a fluid; a rotating member including a base portion accommodated in the fluid chamber, a shaft portion protruding outside the fluid chamber, and a blade portion located in the fluid chamber, the rotating member being rotatable relative to the housing; a stopper wall provided in the housing and configured to limit a rotation angle of the rotating member within the fluid chamber; a torque generating means for generating a torque in cooperation with the stopper wall during relative rotation of the rotating member, the torque generating means includes a vane movably provided on the blade portion and sliding integrally with the blade portion, and a groove provided on an inner peripheral wall of the fluid chamber in the housing, The vane includes a first slide surface provided on the first direction side which slides in contact with the inner circumferential wall of the fluid chamber when the rotating member rotates in a first direction, and a second slide surface provided on the second direction side which slides in contact with the inner circumferential wall of the fluid chamber when the rotating member rotates in a second direction, The groove is formed with a width smaller than the axial length of the vane. A bidirectional rotation damper.

2. Two stopper walls are provided on an inner circumferential surface of the housing to define two fluid chambers, a first fluid chamber and a second fluid chamber, facing each other with the rotating member in between.

2. The bidirectional rotation damper according to claim 1 .

3. The rotating member is supported on the base side by a first bearing and on the shaft side by a second bearing, the housing has an opening on one end side that is closed by a cap, and a bearing protrusion on the other closed end side that supports the first bearing, the first bearing has an air vent hole penetrating from the rotating member side to the bearing protrusion side, The cap supports the rotating member via the second bearing.

2. The bidirectional rotation damper according to claim 1 .

4. 4. The bidirectional rotation damper according to claim 3, wherein the bearing protrusion is provided with a relief groove extending from a tip of the bearing protrusion toward the other end of the housing.

5. 5. The bidirectional rotation damper according to claim 1, wherein the first slide surface and the second slide surface of the vane are formed substantially symmetrically.

6. 6. The bidirectional rotation damper according to claim 1, wherein the vane is provided so as to be swingable in the first direction and the second direction with a tip of the blade portion as a fulcrum.

7. 6. The bidirectional rotation damper according to claim 1, wherein the vane has a through hole penetrating vertically between the first slide surface and the second slide surface, and is formed to be slidable in the first direction and the second direction relative to the blade portion, so that when the vane is slidably moved toward the first direction side, the fluid filled on the first direction side escapes through the through hole to the second direction side, and when the vane is slidably moved toward the second direction side, the fluid filled on the second direction side escapes through the through hole to the first direction side.

Images