Bidirectional rotating damper

Abstract

To provide a bidirectional rotating damper capable of reducing wear by suppressing the occurrence of excessive force in a contact portions between a rotating member and a stopper wall of a housing.SOLUTION: The bidirectional rotating damper includes vanes 25A, 25B movably provided on blade parts 23A, 23B for sliding integrally with the blade parts 23A, 23B, and a recessed groove 28 provided in the housing 12 at an internal peripheral face 12a in a fluid chamber 13. The vanes 25A, 25B includes a first slide face 26A provided on the first direction side for moving to a rotating member 14 in contact with the internal peripheral face in the fluid chamber 13 at rotation to a first direction, and a second slide surface 26B provided on the second direction side for moving to the rotating member 14 in contact with the internal peripheral face 12a in the fluid chamber 13 at rotation to a second direction.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] Conventionally, for example, when opening and closing a lid, a door, etc., a bi-directional rotary damper that applies braking force in both directions during opening and closing is known from Patent Document 1 and the like.

[0003] FIG. 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 and sealed with a fluid, a base portion 103a housed in the fluid chamber 102, and a shaft portion (not shown) protruding outside the fluid chamber 102. The rotary damper 100 has a rotary member 103 that is rotatable relative to the housing 101, a stopper wall 104 provided on the housing 101 to limit the rotation angle of the rotary member 103 in the fluid chamber 102, and blades 103b provided on the base portion 103a of the rotary member 103 for generating torque in cooperation with the stopper wall 104 when the rotary member 103 rotates relatively. Further, the rotary damper 100 has one partition wall 105 and the fluid chamber 102 is also a single chamber. The fluid chamber 102 is partitioned into two chambers, a first fluid chamber 102A and a second fluid chamber 102B, by the blades 103b. As the rotary member 103 rotates, the fluid moves to the first fluid chamber 102A side and the second fluid chamber 102B side, thereby providing braking force in both directions.

[0004] Further, as shown in Fig. 9, when the rotating damper 100 is rotated counterclockwise as shown in Fig. 9(a) and the first fluid chamber 102A enters the high torque region, the rotating member 103 is pushed by the pressure P in the 180-degree facing direction of the high torque region (the direction of arrow 106A in the figure). Conversely, as shown in Fig. 9(b), when the rotating member 103 is rotated clockwise and the second fluid chamber 102B enters the high torque region, the rotating member 103 is pushed by the pressure P in the 180-degree facing direction of the high torque region (the direction of arrow 106B in the figure). That is, depending on the respective rotation directions, the rotating member 103 moves (shifts) in the direction of arrow 106A or arrow 106B.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] As described above, the rotating damper 100 shown in Fig. 9 known from Patent Document 1 etc. has a configuration in which there is one partition wall and the fluid chamber 102 is a single chamber. Therefore, as shown in Fig. 9(a), when the rotating member 103 is rotated counterclockwise and the first fluid chamber 102A enters the high torque region, the rotating member 103 is pushed by the pressure in the 180-degree facing direction of the high torque region (the direction of arrow 106A in the figure) and moves. Conversely, as shown in Fig. 9(b), when the rotating member 103 is rotated clockwise and the second fluid chamber 102B enters the high torque region, the rotating member 103 is pushed by the pressure in the 180-degree facing direction of the high torque region (the direction of arrow 106B in the figure), and there is a problem that the rotating member 103 is in a state of moving (shifting). And due to this action, the rotating member 103 rotates eccentrically, and the outer diameter portion of the rotating member 103 and the partition wall 105 of the housing 101 strongly contact at the portions indicated by reference numeral 107 in Figs. 9(a) and (b), and there is a problem that wear of the portion indicated by reference numeral 107 progresses due to the excessive force.

[0007] Therefore, a technical problem to be solved arises in order to provide a bi-directional rotary damper capable of suppressing the generation of excessive force at the contact portion between the rotating member and the stopper wall of the housing and reducing wear, and an object of the present invention is to solve this problem.

Means for Solving the Problem

[0008] The present invention has been proposed to achieve the above object, and the invention according to claim 1 includes a housing having a fluid chamber filled with a fluid, a rotating member provided with blade portions located in the fluid chamber and rotatable relative to the housing, a stopper wall provided on 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 when the rotating member rotates relatively. In the bi-directional rotary damper, the torque generating means includes a vane movably provided on the blade portion and sliding integrally with the blade portion, and a concave groove provided on the inner peripheral wall of the fluid chamber in the housing. The vane includes a first slide surface provided on the first direction side that slides in contact with the inner peripheral wall of the fluid chamber when the rotating member rotates in the first direction, and a second slide surface provided on the second direction side that slides in contact with the inner peripheral wall of the fluid chamber when the rotating member rotates in the second direction. A bi-directional rotary damper is provided.

[0009] According to this configuration, when the rotating member is rotated in the first direction, the fluid filled in the first direction side of the fluid chamber flows through the concave groove into the fluid chamber on the second direction side, and when the first slide surface is rotated beyond the concave groove, it enters the high torque region and a braking force is applied. Conversely, when the rotating member is rotated in the second direction, the fluid filled in the second direction side of the fluid chamber flows through the concave groove into the fluid chamber on the first direction side, and when the second slide surface is rotated beyond the concave groove, it enters the high torque region and a braking force is applied. Therefore, in this configuration, even when the rotating member rotates and enters the high torque region, the pressure is pushed back in the rotational 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, preventing wear of the outer diameter portion of the rotating member and the stopper wall of the housing due to excessive force caused by the contact.

[0010] The invention according to claim 2 provides a bi-directional rotary damper, in the configuration according to claim 1, wherein two stopper walls are provided on the inner peripheral surface of the housing to form two fluid chambers, namely a first fluid chamber and a second fluid chamber, which face each other with the rotating member therebetween.

[0011] According to this configuration, by forming two fluid chambers, i.e., a first fluid chamber and a second fluid chamber, which face each other with the rotating member interposed therebetween, the pressing forces in each fluid chamber can be balanced, and a state in which the rotating member moves (shifts) in the horizontal direction can be prevented. As a result, further wear between the outer diameter portion of the rotating member and the stopper wall of the housing can be prevented. 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 concave grooves into the fluid chamber on the second direction side, and when the first slide surface rotates beyond one of the concave grooves, it enters the high torque region 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 the rotating member as the center also enters the high torque region beyond the other concave groove, 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 concave grooves into the fluid chamber on the first direction side, and when the second slide surface rotates beyond one of the concave grooves, it enters the high torque region and a braking force is applied. Then, the fluid filled on the second direction side of the second fluid chamber also enters the high torque region beyond the other concave groove, and a braking force is applied simultaneously with the first fluid chamber. Therefore, in this configuration, even when the rotating member rotates and enters the high torque region, the pressures are balanced facing each other with the rotating member as the center, the rotating member rotates without eccentricity, and a state in which the rotating member moves (shifts) in the horizontal direction can be prevented.

[0012] The invention according to claim 3 provides a bi-directional rotation damper, in the configuration according to claim 1, wherein the rotating member further includes a base portion housed in the fluid chamber and a shaft portion protruding outside the fluid chamber, the rotating member is supported on the base portion side by a first bearing and on the shaft portion side by a second bearing, the housing has an opening closed by a cap at one end side and a bearing convex portion for supporting the first bearing at the closed other end side, the first bearing has an air vent hole penetrating 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 by the first bearing on the base side and by the second bearing on the shaft portion side, and the housing and the rotating member are arranged coaxially. As a result, the rotating member can rotate smoothly relative to the housing without eccentricity, and wear of the rotating member, the housing, and the cap can be prevented. Further, since the first bearing is provided with an air vent hole, the press-fitting operation of the first bearing onto the rotating member is facilitated, and the accuracy of the bi-directional rotation damper can be maintained.

[0014] The invention according to claim 4 provides a bi-directional rotation damper, which in the configuration according to claim 3, is provided with a relief groove on the bearing convex portion, extending from the tip of the bearing convex portion toward the other end side of the housing body.

[0015] According to this configuration, since a relief groove is provided on the bearing convex portion, extending from the tip of the bearing convex portion toward the other end side of the housing body, when assembling the bi-directional rotation damper, the fluid that enters and 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 body, and further circulated outside the rotating member and returned to the fluid chamber side.

[0016] The invention according to claim 5 provides a bi-directional rotation damper, which in the configuration according to any one of claims 1 to 4, is formed such that the first slide surface and the second slide surface of the vane are substantially left-right symmetric.

[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 according to claim 6 provides a bi-directional rotation damper, which in the configuration according to any one of claims 1 to 5, is provided such that the vane is 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 swingably fitted and connected to the tip of the blade portion of the rotating member.

[0020] The invention according to claim 7 is configured as described in any one of claims 1 to 5, wherein a through hole penetrating vertically is formed between the first sliding surface and the second sliding surface of the vane, and the vane is formed to be slidable in the first direction and the second direction with respect to the blade portion. When the vane is slid in the first direction, the fluid filled on the first direction side is discharged to the second direction side through the through hole, and when the vane is slid in the second direction, the fluid filled on the second direction side is discharged to the first direction side through the through hole, thereby providing a bi-directional rotary damper.

[0021] According to this configuration, the cross-sectional shape of the connection groove of the vane connected to the blade portion of the rotating member is formed in a substantially rectangular shape, and the connection 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. Further, a fluid flow path can be formed by utilizing the gap and the through hole formed by sliding in the circumferential direction.

[0022] The invention according to claim 8 is configured as described in claim 1, wherein the concave groove is formed with a width smaller than the axial length of the vane, thereby providing a bi-directional rotary damper.

[0023] The invention according to claim 9 is configured as described in claim 1, wherein the first sliding surface and the second sliding surface are provided separately from each other, thereby providing a bi-directional rotary damper.

Effects of the Invention

[0024] According to the present invention, even when the rotating member rotates and enters the high torque region, the pressure is pushed back in the rotational direction opposite to the rotation of the rotating member, and the rotating member is not pressed against the 180-degree facing surface in the high torque region. Therefore, it is possible to prevent the rotating member from moving (shifting) in the horizontal direction. As a result, the outer diameter portion of the rotating member and the stopper wall of the housing come into strong contact, and it is possible to prevent wear and the like of the outer diameter portion of the rotating member and the stopper wall of the housing due to excessive force caused by the contact, and the life of each member can be extended.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Embodiment for Carrying out the Invention

[0026] In order to achieve the object of providing a bi-directional rotation damper capable of suppressing the generation of excessive force at the contact portion between the rotating member and the stopper wall of the housing and reducing wear, a housing having a fluid chamber filled with fluid, a rotating member provided with blade portions located in the fluid chamber and rotatable relative to the housing, a stopper wall provided on 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 when the rotating member rotates relatively. In the bi-directional rotation damper, the torque generating means includes a vane movably provided on the blade portion and sliding integrally with the blade portion, and a concave groove provided on the inner peripheral wall of the fluid chamber in the housing. The vane is provided with a first slide surface provided on the first direction side that slides in contact with the inner peripheral wall of the fluid chamber when the rotating member rotates in the first direction, and a second slide surface provided on the second direction side that slides in contact with the inner peripheral wall of the fluid chamber when the rotating member rotates in the second direction. This is realized by adopting such a configuration.

Example

[0027] Hereinafter, an example according to an embodiment of the present invention will be described in detail based on the accompanying drawings. In the following examples, when referring to the number of components, numerical values, amounts, ranges, etc., unless otherwise specifically stated and unless it is clearly limited to a specific number in principle, it is not limited to that specific number, and it may be more or less than the specific number.

[0028] In addition, when referring to the shape, positional relationship, etc. of components, etc., unless otherwise specified or it is considered not to be so in principle, it includes those that are substantially approximated or similar to the shape, etc.

[0029] In addition, the drawings may be exaggerated, such as by enlarging characteristic parts for easier understanding of the features, and the dimensional ratios of components, etc. are not necessarily the same as in reality. Also, in cross-sectional views, hatching of some components may be omitted to make the cross-sectional structure of the components easier to understand.

[0030] In addition, in the following description, expressions indicating directions such as up and down, left and right, etc. are not absolute. They are appropriate when the parts of the bi-directional rotary damper of the present invention are depicted in a certain posture. However, when the posture changes, they should be interpreted according to the change in posture. Also, the same reference numerals are assigned to the same elements throughout the description of the embodiments.

[0031] FIG. 1 and FIG. 2 show the bi-directional rotary damper 10A of the first embodiment according to the present invention. FIG. 1(a) is a front view thereof, FIG. 1(b) is a cross-sectional view taken along line A-A of FIG. 1(a), FIG. 1(c) is a cross-sectional view taken along line B-B of FIG. 1(b), and FIG. 2 is an exploded perspective view of the bi-directional rotary damper 10A. In the following description, the left side in the left-right direction in FIG. 1(b) is described as the front in the front-rear direction of the bi-directional rotary damper 10A, and the right side is described as the rear.

[0032] In FIGS. 1 and 2, the bi-directional rotary damper 10A has a structure in which the base portion 14A of the rotating member 14 is incorporated into the fluid chamber 13 of the housing 12 filled and sealed with a fluid 11 such as highly viscous silicone oil, and the shaft portion 14B of the rotating member 14 protrudes outside the fluid chamber 13.

[0033] The housing 12 is made of die-cast. 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 projection 15 is formed at the central portion on the fluid chamber 13 side of the closed end 12A. The other end 12B of the housing 12 (hereinafter referred to as the "open end 12B") is open, and an annular resin pressure partition plate 16 forming the other side wall of the fluid chamber 13, a rubber O-ring 17A and an O-ring 17B which are sealing members, are interposed, and an annular die-cast end cap 18 is fitted and fixed thereto and closed in a sealed state. The fitting and fixing of the end cap 18 and the open end 12B are performed by screw connection between a male screw formed on the outer periphery of the end cap 18 and a female screw formed on the inner periphery of the opening of the open end 12B.

[0034] The rotating member 14 is supported by the bearing projection 15 of the housing 12 via a first bearing 20 composed of a bush inserted into a recess 19 provided at one end of the base 14A of the base 14A, and the shaft portion 14B passes through the central portions of the pressure partition plate 16 and the end cap 18 and is supported by the end cap 18 via a second bearing 21 composed of a bush interposed between the end cap 18 and the shaft portion 14B. And the rotating member 14 is disposed rotatably relative to the housing 12 by being supported by the first bearing 20 and the second bearing 21.

[0035] The fluid chamber 13 of the housing 12 is provided with two stopper walls 22 protruding from the inner peripheral surface 12a of the housing 12 toward the center, and the inside of the fluid chamber 13 is partitioned into a first fluid chamber 13A and a second fluid chamber 13B by the two stopper walls 22. The two stopper walls 22 are provided with a circumferential displacement of approximately 180 degrees from each other, and the protrusion of each stopper wall 22 extends to a position substantially 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 with a circumferential displacement of approximately 180 degrees from each other.

[0036] The stopper wall 22 also has the functions of limiting the rotation angle of the rotating member 14 and generating torque. On a part of the outer peripheral surface of the base portion 14A of the rotating member 14, convex first blade portions 23A and second blade portions 23B are provided along the axial direction of the rotating member 14 at positions displaced from each other by approximately 180 degrees in the circumferential direction. Further, at the tip portions of the first blade portion 23A and the second blade portion 23B, first vanes 25A and second vanes 25B that constitute torque generating means for generating torque in cooperation with the stopper wall 22 are respectively mounted on the tip portions of the first blade portion 23A and the second blade portion 23B so as to be swingable in the circumferential direction of the rotating member 14.

[0037] The tip portions of the first blade portion 23A and the second blade portion 23B have a circular cross-section, and the connecting portion 24A of the first vane 25A and the second vane 25B has a groove with a C-shaped cross-section. The connecting portion 24A is provided at a substantially central portion in the rotation direction of the first vane 25A and the second vane 25B, corresponding to the tip portions of the first blade portion 23A and the second blade portion 23B, respectively. Then, the tip portion of the first blade portion 23A and the first vane 25A, and the tip portion of the second blade portion 23B and the second vane 25B are respectively connected so as to be swingable (or rotatable) in the circumferential direction of the rotating member 14 by fitting the circular cross-section tip portions of the first blade portion 23A and the second blade portion 23B into the C-shaped connecting portion 24A. After connection, the first vane 25A and the second vane 25B are mounted so as to be reciprocally swingable in the circumferential direction of the rotating member 14 with the tip portions of the first blade portion 23A and the second blade portion 23B as fulcrums. Further, after mounting, when the rotating member 14 is rotated, the first vane 25A and the second vane 25B move along the inner peripheral surface 12a of the housing 12 that is integrated with the rotating member 14 in the same direction.

[0038] The first vane 25A and the second vane 25B have substantially the same structure. Also, the first vane 25A and the second vane 25B are shown as single components in FIG. 3. Adding further explanation 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 in a substantially bilaterally symmetric shape on the outer surface side facing the inner peripheral surface 12a of the housing 12 and on both sides in the rotational direction of the rotating member 14 with the connecting portion 24A interposed therebetween. Further, in the front and rear portions of the first slide surface 26A and the second slide surface 26B, portions recessed inward from the first slide surface 26A and the second slide surface 26B, that is, recesses 27 are formed. When the rotating member 14 rotates in the first direction (clockwise direction), the first vane 25A and the second vane 25B rotate in the second direction (counterclockwise direction) with the tip portions of the first blade portion 23A and the second blade portion 23B as fulcrums respectively, the second slide surface 26B moves away from the inner peripheral surface 12a of the housing 12, and the first slide surface 26A slides in the first direction while contacting the inner peripheral 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 portions of the first blade portion 23A and the second blade portion 23B as fulcrums respectively, the first slide surface 26A moves away from the inner peripheral surface 12a of the housing 12, and the second slide surface 26B slides in the second direction while contacting the inner peripheral surface 12a of the housing 12.

[0039] Also, on the inner peripheral surface 12a that forms the fluid chamber 13 of the housing 12, concave grooves 28 are provided corresponding to the first fluid chamber 13A and the second fluid chamber 13B, respectively. As shown in Fig. 1(b), the axial width of the concave groove 28 is formed to be slightly smaller than the axial widths of the first vane 25A and the second vane 25B. Further, both circumferential ends of the concave groove 28 are extended to positions slightly corresponding to the recess 27 in the states shown in Figs. 4(a) and 4(c) described later, where the rotations of the first vane 25A and the second vane 25B are limited by the stopper wall 22, so that the fluid 11 in the high torque region can be discharged to the low torque region side through the concave groove 28.

[0040] Also, the first bearing 20 is provided with an air vent hole 29 penetrating from the rotating member 14 side to the bearing convex portion 15 side. On the outer peripheral surface of the bearing convex portion 15, a relief groove 30 is provided that is continuously formed from the tip of the bearing convex portion 15 toward the other end side of the housing 12, that is, from the tip of the bearing convex portion 15 to the inner surface of the closed end portion 12A. The air vent hole 29 facilitates the press-fitting operation of the first bearing 20 onto the rotating member 14 by discharging the air that has entered between the first bearing 20 and the rotating member 14 through the air vent hole 29, and can maintain the accuracy of the bidirectional rotation 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 convex portion 15 to the other end side (closed end portion 12A side) of the housing 12 through the relief groove 30, and further returns it to the fluid chamber 13 side after going around the outside of the rotating member 14.

[0041] Fig. 4 is an operation diagram of the bidirectional rotation damper 10A. The operation of the bidirectional rotation damper 10A will be described next with reference to Fig. 4.

[0042] In Fig. 4(a), when the rotating member 14 rotates in the first direction (clockwise direction) indicated by the arrow 51A, the pressure receiving surfaces 31 of the first vane 25A and the second vane 25B are resisted by the viscous fluid 11 in the fluid chamber 13. The first vane 25A and the second vane 25B rotate counterclockwise in the direction indicated by the arrow 52A with the tip portions of the first blade portion 23A and the second blade portion 23B as fulcrums, and the first sliding surface 26A comes into contact with the inner peripheral surfaces 12a of the first fluid chamber 13A and the second fluid chamber 13B, respectively. Since recesses 27 are formed as fluid passages in the first sliding surface 26A and the second sliding surface 26B of the first vane 25A and the second vane 25B, the fluid 11 on the clockwise side in the first fluid chamber 13A and the second fluid chamber 13B flows counterclockwise through the concave groove 28 and the recess 27 as indicated by the dotted line 11A in Fig. 4(a). As a result, the rotating member 14 and the housing 12 rotate relative to each other with low torque.

[0043] Further, as the rotation of the rotating member 14 progresses, the first sliding surface 26A reaches the end of the concave groove 28 provided on the inner peripheral surface 12a of the housing 12, and as shown in Fig. 4(b), the first sliding surface 26A comes into contact with the inner peripheral surfaces 12a of the first fluid chamber 13A and the second fluid chamber 13B, respectively. And until 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 the low torque region where it flows counterclockwise through the concave 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 sliding surface 26A comes into contact with the inner peripheral surfaces 12a of the first fluid chamber 13A and the second fluid chamber 13B beyond the portion where the concave groove 28 is provided, the fluid 11 flows little by little counterclockwise through the gaps between the inner peripheral surface 12a of the housing 12 and the first vane 25A and the second vane 25B, and the gaps 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 the high torque region and rotate relatively gently. This gentle relative rotation continues until the first vane 25A and the second vane 25B hit the stopper wall 22 and the rotation is restricted. Fig. 4(c) shows the state in that high torque region.

[0044] 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 of stopping at the first-direction end shown in Fig. 4(c) to the second-direction (counterclockwise direction) end will be described.

[0045] In Fig. 4(d), when the rotating member 14 rotates in the second direction (counterclockwise direction) indicated by the arrow 51B, the pressure-receiving surfaces 31 of the first vane 25A and the second vane 25B receive 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 portions of the first blade portion 23A and the second blade portion 23B as fulcrums, respectively, and the second slide surface 26B comes into contact with the inner peripheral surfaces 12a of the first fluid chamber 13A and the second fluid chamber 13B. Since recesses 27 as fluid passages are formed in the first slide surface 26A and the second slide surface 26B of the first vane 25A and the second vane 25B, the fluid 11 on the counterclockwise direction side in the first fluid chamber 13A and the second fluid chamber 13B flows to the clockwise direction side through the concave groove 28 and the recess 27. As a result, the rotating member 14 and the housing 12 relatively rotate with low torque.

[0046] Further, as the rotation of the rotating member 14 progresses, the first slide surface 26A reaches the end of the concave groove 28 provided on the inner peripheral surface 12a of the housing 12. As shown in FIG. 4(e), the second slide surface 26B comes into contact with the inner peripheral surfaces 12a of the first fluid chamber 13A and the second fluid chamber 13B, respectively. And until the state shown in FIG. 4(e) is reached, 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 concave groove 28 and the concave portion 27, and the rotating member 14 and the housing 12 can be relatively rotated with low torque. However, when the second slide surface 26B comes into contact with the inner peripheral surfaces 12a of the first fluid chamber 13A and the second fluid chamber 13B beyond the portion where the concave groove 28 is provided, the fluid 11 gradually flows clockwise through the gaps between the inner peripheral surface 12a of the housing 12 and the first vane 25A and the second vane 25B, and the gaps between the first blade portions 23A and 23B and the first vane 25A and the second vane 25B, respectively. As a result, the rotating member 14 and the housing 12 enter the high torque region and rotate relatively gently. This gentle relative rotation continues until the first vane 25A and the second vane 25B hit the stopper wall 22 and the rotation is restricted. FIG. 4(f) shows the state in the high torque region.

[0047] Therefore, in the bidirectional rotation damper 10A shown in the first embodiment, regardless of whether it rotates in the first direction (clockwise) or the second direction (counterclockwise), it can be smoothly rotated with low torque before reaching the end, and when approaching the end, it can be rotated gently with high torque. Thus, when this bidirectional rotation damper 10A is applied to the opening and closing mechanism with the lid door, braking force can be applied in both directions during opening and closing. Therefore, at the end of the closing direction, it can be gently closed to prevent accidents such as finger pinching.

[0048] Also, when the rotating member 14 rotates in the first direction, the fluid 11 filled on the first direction side of the fluid chamber 13 flows through the recess 27 and the concave groove 28 into the fluid chamber 13 on the second direction side. When the first slide surface 26A rotates beyond the concave groove 28, it enters the high torque region and a braking force is applied. Conversely, when the rotating member 14 rotates in the second direction, the fluid 11 filled on the second direction side of the fluid chamber 13 flows through the recess 27 and the concave groove 28 into the fluid chamber 13 on the first direction side. When the second slide surface 26B rotates beyond the concave groove 28, it enters the high torque region and a braking force is applied. Therefore, in this configuration, even when the rotating member 14 rotates and enters the high torque region, the pressure is balanced symmetrically around the rotating member 14, and the rotating member 14 rotates without eccentricity, preventing the rotating member 14 from moving (shifting) in the horizontal direction. As a result, it is possible to prevent the base 14A of the rotating member 14 from strongly contacting the stopper wall 22 of the housing 12. In other words, it is possible to prevent wear caused by the strong contact between the base 14A of the rotating member 14 and the stopper wall 22 of the housing 12.

[0049] FIGS. 5 and 6 show the bi-directional rotation damper 10B according to the second embodiment of the present invention. FIG. 5(a) is a front view thereof, FIG. 5(b) is a cross-sectional view taken along line E-E of FIG. 5(a), FIG. 5(c) is a cross-sectional view taken along line F-F of FIG. 5(b), and FIG. 6 is an exploded perspective view of the bi-directional rotation damper 10B. In the following description, the left side in the left-right direction in FIG. 5(b) will be described as the front in the front-rear direction of the bi-directional rotation damper, and the right side as the rear. Also, the bi-directional rotation damper 10B of the second embodiment shown in FIGS. 5 and 6 is a modification of the structure of the first vane portion 23A, the second vane portion 23B, the first vane 25A, and the second vane 25B of the base 14A in the bi-directional rotation damper 10A of the first embodiment shown in FIGS. 1 to 4. Other structures are substantially the same and perform the same functions. Therefore, the same members as those in the bi-directional rotation damper 10A of the first embodiment shown in FIGS. 1 to 4 are denoted by the same reference numerals and the description thereof will be partially omitted.

[0050] In FIGS. 5 and 6, the bi-directional rotation damper 10B has a structure in which the base 14A of the rotating member 14 is incorporated into the fluid chamber 13 of the housing 12 filled and sealed with a fluid 11 such as highly viscous silicone oil, and the shaft portion 14B of the rotating member 14 protrudes outside the fluid chamber 13.

[0051] The housing 12 is made of die-cast. 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 projection 15 is formed at the central portion on the fluid chamber 13 side of the closed end 12A. The other end 12B of the housing 12 (hereinafter referred to as the "open end 12B") is open, and an annular resin pressure partition plate 16 forming the other side wall of the fluid chamber 13 and rubber O-rings 17A and 17B serving as seal members are interposed therebetween, and an annular die-cast end cap 18 is fitted and fixed in a sealed state. The fitting and fixing of the end cap 18 to the open end 12B is performed by screw connection between the male screw formed on the outer periphery of the end cap 18 and the female screw formed on the inner periphery of the opening of the open end 12B.

[0052] The rotating member 14 is supported by the bearing projection 15 of the housing 12 via a first bearing 20 composed of a bush inserted into a recess 19 provided at one end of the base 14A of the base 14A, and the shaft portion 14B passes through the central portions of the pressure partition plate 16 and the end cap 18 and is supported by the end cap 18 via a second bearing 21 composed of a bush interposed between the end cap 18 and the shaft portion 14B. And the rotating member 14 is disposed rotatably relative to the housing 12 by being supported by the first bearing 20 and the second bearing 21.

[0053] The fluid chamber 13 of the housing 12 is partitioned into a first fluid chamber 13A and a second fluid chamber 13B by providing two stopper walls 22 that project from the inner peripheral surface 12a of the housing 12 toward the center. The two stopper walls 22 are provided with a circumferential displacement of approximately 180 degrees from each other, and the projection of each stopper wall 22 extends to a position substantially in contact with the outer peripheral surface of the base portion 14A. Therefore, the first fluid chamber 13A and the second fluid chamber 13B are provided with a circumferential displacement of approximately 180 degrees from each other.

[0054] The stopper wall 22 also has a function of limiting the rotation angle of the rotating member 14 and a function of generating torque. On a part of the outer peripheral surface of the base portion 14A of the rotating member 14, a convex first blade portion 23C and a second blade portion 23D are provided along the axial direction of the rotating member 14 at positions circumferentially displaced from each other by approximately 180 degrees. At the tip portions of the first blade portion 23C and the second blade portion 23D, a first vane 25C and a second vane 25D that constitute torque generating means for generating torque in cooperation with the stopper wall 22 are respectively slidably mounted on the tip portions of the first blade portion 23C and the second blade portion 23D by an amount limited in the circumferential direction of the rotating member 14.

[0055] The tip of the first vane root 23C and the tip of the second vane root 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 at a substantially central portion in the rotational direction of the first vane 25C and the second vane 25D, corresponding to the tip of the first vane root 23C and the tip of the second vane root 23D, respectively. The tip of the first vane root 23C and the first vane 25C, and the tip of the second vane root 23D and the second vane 25D are slidably and loosely fitted with the rectangular cross-section tips of the first vane root 23C and the second vane root 23D into the connecting portion 24B forming a rectangular cross-section groove, respectively, and are connected so as to be slidable by a limited amount in the circumferential direction of the rotating member 14. That is, the groove width in the circumferential direction of the connecting portion 24B is formed larger than the circumferential width of the tips of the first vane root 23C and the second vane root 23D, and the first vane 25C and the second vane 25D can slide in the circumferential direction with respect to the first vane root 23C and the second vane root 23D by the difference between the groove width and the circumferential width of the tip. Further, notches 33 removed from the tip surface toward the base 14A are provided at the tips of the first vane root 23C and the second vane root 23D, respectively. The notch 33 functions as a flow path for the fluid 11.

[0056] The first vane 25C and the second vane 25D have substantially the same structure. Also, the first vane 25C and the second vane 25D are shown as single parts in FIG. 7. Further explaining with reference to FIG. 7, the first vane 25C and the second vane 25D are provided with a first sliding surface 26C and a second sliding surface 26D in a substantially bilaterally symmetric shape on the outer surface side facing the inner circumferential surface 12a of the housing 12 and on both sides in the rotational direction of the rotating member 14 with the connecting portion 24B interposed therebetween. Further, recessed portions 27, which are recessed inward from the first sliding surface 26C and the second sliding surface 26D, are formed in the front and rear portions of the first sliding surface 26C and the second sliding surface 26D, respectively. Further, a through hole 32, which functions as a flow path for the fluid 11 and penetrates to the connecting portion 24B, is provided at a substantially central position of the recess 27.

[0057] When the first slide surface 26C and the second slide surface 26D rotate in the first direction (clockwise direction), the first vane 25C and the second vane 25D slide in the second direction (counterclockwise direction) with respect to the tip of the first blade portion 23C and the tip of the second blade portion 23D, and the side surfaces of the tips on the second direction side of the first blade portion 23C and the second blade portion 23D are separated from the inner surfaces on the second direction side of the first vane 25C and the second vane 25D, and the fluid 11 forms a passage flowing in the second direction side (counterclockwise direction side) through the gaps between the recess 27, the through hole 32, the notch 33, and the base portion 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) with respect to the tip of the first blade portion 23C and the tip of the second blade portion 23D, and the side surfaces of the tips on the first direction side of the first blade portion 23C and the second blade portion 23D are separated from the inner surfaces on the first direction side of the first vane 25C and the second vane 25D, and the fluid 11 forms a passage flowing in the first direction side through the gaps between the recess 27, the through hole 32, the notch 33, and the base portion 14A.

[0058] In addition, concave grooves 28 are provided on the inner peripheral surface 12a forming the fluid chamber 13 of the housing 12 corresponding to the first fluid chamber 13A and the second fluid chamber 13B, respectively. As shown in FIG. 5(b), the axial width of the concave groove 28 is formed slightly smaller than the axial width of the first vane 25C and the second vane 25D. Further, both ends in the circumferential direction of the concave groove 28 are extended to positions slightly corresponding to the recess 27 in the state shown in FIGS. 8(a) and 8(c) described later where 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 be discharged to the low torque region side through the concave groove 28.

[0059] Further, the first bearing 20 is provided with an air vent hole 29 that penetrates from the rotating member 14 side to the bearing convex portion 15 side. On the outer peripheral surface of the bearing convex portion 15, a relief groove 30 is formed continuously from the tip of the bearing convex portion 15 toward the other end side of the housing 12, that is, from the tip of the bearing convex portion 15 to the inner surface of the closing end portion 12A. The air vent hole 29 vents the air that has entered between the first bearing 20 and the rotating member 14 through the air vent hole 29, facilitating the press-fitting operation of the first bearing 20 onto the rotating member 14 and maintaining the accuracy of the bidirectional rotation 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 convex portion 15 through the relief groove 30 to the other end side (closing end portion 12A side) of the housing 12, and further circulates it outside the rotating member 14 and returns it to the fluid chamber 13 side.

[0060] FIG. 8 is an operation diagram of the bidirectional rotation damper 10B. The operation of the bidirectional rotation damper 10B will be described below with reference to FIG. 8.

[0061] In FIG. 8(a), when the rotating member 14 rotates in the first direction (clockwise direction) indicated by the 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) with respect to the tip portions of the first blade portion 23C and the second blade portion 23D, respectively, so that the sides of the tip portions on the second direction side of the first blade portion 23C and the second blade portion 23D and the inner surfaces on the second direction side of the first vane 25C and the second vane 25D are separated, and a gap is formed between the fluid 11 in the recess 27, the through hole 32, the notch 33, and the base portion 14A. Further, since the recess 27 as a fluid passage is formed in the first sliding surface 26C and the second sliding surface 26D of the first vane 25C and the second vane 25D, the fluid 11 on the clockwise direction side in the first fluid chamber 13A and the second fluid chamber 13B enters the recess 27 from the concave groove 28 as shown by the dotted line 11A in FIG. 8(a), and further flows in the second direction (counterclockwise direction) through the gap between the through hole 32, the notch 33, and the base portion 14A. As a result, the rotating member 14 and the housing 12 relatively rotate with low torque.

[0062] Further, as the rotation of the rotating member 14 progresses, the first slide surface 26C reaches the end of the concave groove 28 provided on the inner peripheral surface 12a of the housing 12, and as shown in FIG. 8(b), the first slide surface 26C is in contact with the inner peripheral surfaces 12a of the first fluid chamber 13A and the second fluid chamber 13B, respectively. And until 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 flowing counterclockwise through the concave groove 28 and the recess 27, and the rotating member 14 and the housing 12 can be relatively rotated at a low torque. However, when the first slide surface 26C comes into contact with the inner peripheral surfaces 12a of the first fluid chamber 13A and the second fluid chamber 13B respectively beyond the portion where the concave groove 28 is provided, the fluid 11 flows little by little counterclockwise through the gaps between the inner peripheral surface 12a of the housing 12 and the first vane 25C and the second vane 25D, the gaps between the first blade portions 23C and 23D and the first vanes 25A and 25B, and the notches 33 and the through holes 32. As a result, the rotating member 14 and the housing 12 enter the high torque region and rotate relatively gently. This gentle relative rotation continues until the first vane 25C and the second vane 25D hit the stopper wall 22 and the rotation is restricted. FIG. 8(c) shows the state of the high torque region.

[0063] 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 in the second direction end (counterclockwise direction) from the state where it has stopped at the first direction end shown in FIG. 8(c) will be described.

[0064] In Fig. 8(d), when the rotating member 14 rotates in the second direction (counterclockwise direction) indicated by the 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) with respect to the tip portions of the first blade portion 23C and the second blade portion 23D, respectively, so that the distance between the side surfaces of the tip portions on the second direction side of the first blade portion 23C and the second blade portion 23D and the inner surfaces on the first direction side of the first vane 25C and the second vane 25D increases, and a gap is formed through which the fluid 11 can pass between the recess 27, the through hole 32, the notch 33, and the base portion 14A. Further, since the recess 27 as a fluid passage is formed in the first sliding surface 26C and the second sliding surface 26D of the first vane 25C and the second vane 25D, the fluid 11 on the clockwise direction side in the first fluid chamber 13A and the second fluid chamber 13B enters the recess 27 from the concave groove 28 as shown by the dotted line 11A in Fig. 8(d), and further flows in the first direction (clockwise direction) through the gap between the through hole 32, the notch 33, and the base portion 14A. As a result, the rotating member 14 and the housing 12 relatively rotate with low torque.

[0065] Also, as the rotation of the rotating member 14 progresses, the second sliding surface 26D reaches the end of the concave groove 28 provided on the inner peripheral surface 12a of the housing 12, and as shown in FIG. 8(e), the second sliding surface 26D contacts the inner peripheral surfaces 12a of the first fluid chamber 13A and the second fluid chamber 13B, respectively. And until the state shown in FIG. 8(e) is reached, 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 concave groove 28 and the recess 27, and the rotating member 14 and the housing 12 can be relatively rotated at a low torque. However, when the second sliding surface 26D contacts the inner peripheral surfaces 12a of the first fluid chamber 13A and the second fluid chamber 13B beyond the portion where the concave groove 28 is provided, the fluid 11 passes through the gaps between the inner peripheral surface 12a of the housing 12 and the first vane 25C and the second vane 25D, the gaps between the first blade portions 23C and 23D and the first vane 25C and the second vane 25D, and the notches 33 and the through holes 32, and flows little by little clockwise. As a result, the rotating member 14 and the housing 12 enter a high torque region and rotate relatively gently. This gentle relative rotation continues until the first vane 25C and the second vane 25D hit the stopper wall 22 and the rotation is restricted. FIG. 8(f) shows the state in the high torque region.

[0066] Therefore, also in the bidirectional rotation damper 10B shown as the second embodiment, regardless of whether it rotates in the first direction (clockwise) or the second direction (counterclockwise), it can be smoothly rotated at a low torque before reaching the end, and when approaching the end, it can be rotated gently at a high torque. Thus, when this bidirectional rotation damper 10B is applied to the opening and closing mechanism with the lid door, braking force can be applied in both directions during opening and closing, so that it can be gently closed at the end in the closing direction and prevent accidents such as finger pinching.

[0067] Further, when the rotating member 14 is rotated in the first direction, the fluid 11 filled on the first direction side of the fluid chamber 13 flows through the recess 27 and the groove 28 into the fluid chamber 13 on the second direction side. When the first slide surface 26C is rotated beyond the groove 28, it enters the high torque region and a braking force is applied. Conversely, when the rotating member 14 is rotated in the second direction, the fluid 11 filled on the second direction side of the fluid chamber 13 flows through the recess 27 and the groove 28 into the fluid chamber 13 on the first direction side. When the second slide surface 26D is rotated beyond the groove 28, it enters the high torque region and a braking force is applied. Therefore, with this configuration, even when the rotating member 14 rotates and enters the high torque region, the pressure is balanced symmetrically around the rotating member 14, and the rotating member 14 rotates without eccentricity, preventing the rotating member 14 from moving (shifting) in the horizontal direction. As a result, strong contact between the base portion 14A of the rotating member 14 and the stopper wall 22 of the housing 12 can be prevented. 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.

[0068] 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 groove 28 and the recess 27, etc.

[0069] Further, the present invention can be variously modified without departing from the spirit of the present invention, and it is natural that the present invention extends to such modified ones.

Explanation of Reference Numerals

[0070] 10A: Bidirectional Rotating Damper 10B: Bidirectional Rotating Damper 11: Fluid 11A: Fluid Flow 12: Housing 12A: Closed End 12B: Open End 12a: Inner Peripheral Surface 13: Fluid Chamber 13A: First Fluid Chamber 13B: Second Fluid Chamber 14: Rotating member 14A: Base part 14B: Shaft part 15: Bearing convex part 16: Pressure partition plate 17A: O-ring 17B: O-ring 18: End cap 19: Concave part 20: First bearing 21: Second bearing 22: Stopper wall 23A: First blade root 23B: Second blade root 23C: First blade root 23D: Second blade root 24A: Connecting part 24B: Connecting part 25A: First vane 25B: Second vane 25C: First vane 25D: Second vane 26A: First sliding surface 26B: Second sliding surface 26C: First sliding surface 26D: Second sliding surface 27: Concave part 28: Concave 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: Rotary damper 101: Housing 102: Fluid chamber 102A: First fluid chamber 102B: Second fluid chamber 103: Rotating member 103a: Base part 103b: Blade 104: Stopper wall 105: Partition wall 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 blade portion located in the fluid chamber and 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. 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 further includes a base portion accommodated in the fluid chamber and a shaft portion protruding outside the fluid chamber, 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.

8. 2. The bidirectional rotation damper according to claim 1, wherein the groove is formed to have a width smaller than an axial length of the vane.

9. 2. The bidirectional rotation damper according to claim 1, wherein the first slide surface and the second slide surface are provided separately from each other.

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