Rotary damper and deformation restriction member therefor

Abstract

Provided are: a deformation restriction member (50) for a rotary damper (1), the deformation restriction member (50) being able to inhibit the deformation of a closing member (11) caused by the internal pressure of a case body (2); and a rotary damper (1) comprising the deformation restriction member (50). This deformation restriction member (50) comprises: a body (52) that has a fastening part (54) which is fastened to a shaft (44) coaxially and integrally connected to a rotary part (3); and a pressing part (53) that is provided integrally with the body (52) and that presses the closing member (11) of the case body (2) of the rotary damper (1) toward a housing (10).

Description

Rotary damper and its deformation restricting member

[0001] The present invention relates to a deformation restricting member for a rotary damper and a rotary damper provided with the same.

[0002] Conventionally, a pressure type (pressure resistance type) rotary damper that attenuates kinetic energy in a rotating mechanism by generating torque in response to compression when a rotor rotates in oil sealed inside a case body is known. The case body has a bottomed cylindrical housing that partitions a pressure chamber for storing oil and a lid-shaped closing member (plug), and these are held axially with respect to each other and the pressure chamber is sealed liquid-tightly (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2015-178852

[0004] When the internal pressure of the case body is high, the closing member is pushed up in the rotational axis direction with respect to the housing by the pressure and slightly deformed, and an unintended clearance occurs between the rotor and the closing member and between the closing member and the housing, and there is concern that the designed pressure cannot be obtained and the torque performance becomes lower than expected.

[0005] The present invention has been made in view of such points, and an object thereof is to provide a deformation restricting member for a rotary damper that can suppress deformation of a closing member caused by the internal pressure of a case body and a rotary damper provided with the same.

[0006] The present invention is a deformation restricting member for a rotary damper used in a rotary damper including a case body having a housing and a closing member, a rotating portion rotatable with respect to the case body, and a fluid sealed inside the case body between the housing and the closing member for generating a torque corresponding to the rotating portion with respect to the case body, and includes a main body portion having a fastening portion fastened to a shaft coaxially and integrally connected to the rotating portion, and a pressing portion provided integrally with the main body portion for pressing the closing member against the housing side.

[0007] According to the present invention, deformation of the closing member caused by the internal pressure of the case body can be suppressed.

[0008] This is a cross-sectional view showing a rotary damper according to the first embodiment of the present invention. This is a plan view showing a part of the rotary damper. This is a perspective view showing a deformation-restricting member of the rotary damper. This is a perspective view showing an example of a shaft connected to the rotary damper. (a) is a plan view showing the rotary damper, (b) is a plan view showing the deformation-restricting member from the rear side, and (c) is a side view showing an enlarged part of the anti-rotation mechanism. This is a perspective view showing an example of use of the rotary damper. This is a perspective view showing a deformation-restricting member of a rotary damper according to the second embodiment of the present invention. This is a perspective view showing a deformation-restricting member of a rotary damper according to the third embodiment of the present invention. This is a cross-sectional view showing a rotary damper according to the fourth embodiment of the present invention. (a) is a perspective view showing the deformation-restricting member of the rotary damper from the outside, and (b) is a perspective view showing the deformation-restricting member from the side of the closing member. This is a perspective view showing the closing member of the rotary damper. This is a plan view showing a part of the anti-rotation mechanism of the rotary damper. This is a perspective view showing an example of use of the rotary damper. This is a cross-sectional view showing a rotary damper according to the fifth embodiment of the present invention. This is a perspective view showing the deformation restricting member of the rotary damper. This is a perspective view showing an example of use of the rotary damper. This shows the deformation restricting member of the rotary damper according to the sixth embodiment of the present invention, with (a) being a perspective view and (b) being an enlarged perspective view of a part thereof. This shows the closing member of the rotary damper, with (a) being a perspective view and (b) being an enlarged perspective view of a part thereof. This is an enlarged side view showing a part of the anti-rotation mechanism of the rotary damper, with (a) showing the deformation restricting member rotating in the fastening direction and (b) showing the deformation restricting member rotating in the loosening direction.

[0009] Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

[0010] In Figure 1, 1 is a rotary damper. The rotary damper 1 generally comprises a case body 2 and a rotating part 3 that is rotatable relative to the case body 2. A fluid (viscous fluid) 4, such as silicone oil, is sealed inside the case body 2. The rotary damper 1 of this embodiment is a pressure-type (pressure-resistance type) damper that generates torque by utilizing the compression resistance of the fluid 4 as the rotating part 3 rotates relative to the case body 2, and uses this torque to dampen the kinetic energy in the rotating mechanism. For the sake of clarity in the following explanation, using Figure 1 as a reference, one direction along the rotation axis A of the rotary damper 1 (direction of arrow U) will be described as the upward direction, and the opposite direction (direction of arrow D) will be described as the downward direction. However, this does not mean that the vertical direction of the rotary damper 1 in use is limited to the vertical direction described in this embodiment.

[0011] The case body 2 is the housing of the rotary damper 1. The case body 2 includes a housing 10 and a closing member 11. In this embodiment, the case body 2 is formed in a flat, thin shape, with its axial dimension being smaller than its outer diameter.

[0012] The housing 10 is formed from a metal material such as zinc. The housing 10 has a bearing portion 15 in the center, and side walls 17 rise from the outer edge of a support portion 16 that extends flange-like from the bearing portion 15, forming a bottomed cylindrical shape.

[0013] The bearing portion 15 forms the inner circumference of the housing 10. The bearing portion 15 is the part that rotatably supports the rotating portion 3. The bearing portion 15 is cylindrical with the rotation axis A as its central axis.

[0014] The support portion 16 is flat in the direction perpendicular to the axis. The support portion 16 constitutes the bottom of the housing 10. The support portion 16 is formed by extending continuously around the entire circumference of the bearing portion 15.

[0015] The side wall portion 17 constitutes the outer circumference of the housing 10. The side wall portion 17 is cylindrical and arranged coaxially with the bearing portion 15. The upper end of the side wall portion 17 extends above the upper end of the bearing portion 15. A mounting groove portion 22 is formed at the upper end of the side wall portion 17, to which a sealing member 21 such as an annular O-ring is attached. A holding portion 23 is formed at the upper end of the side wall portion 17, outside the mounting groove portion 22, for holding the outer edge of the closing member 11. The holding portion 23 is configured to be crimped or deformed above the mounting groove portion 22, for example toward the rotation axis A, that is, radially inward, so as to sandwich the outer edge of the closing member 11 from above and below with the sealing member 21 interposed.

[0016] Furthermore, as shown in Figures 1 and 2, a compression wall portion 25 is formed in the housing 10. The compression wall portion 25, also called a fixed vane, is a wall portion that generates torque by compressing the fluid 4 between itself and the rotating portion 3. The compression wall portion 25 is located radially away from the bearing portion 15. The compression wall portion 25 is formed across the side wall portion 17 and the support portion 16. In this embodiment, the compression wall portion 25 is formed by deforming a part of the support portion 16 so that it protrudes upward. One or more compression wall portions 25 are formed. In this embodiment, one compression wall portion 25 is arranged on each side opposite to each other with respect to the rotation axis A. The compression wall portion 25 has a predetermined width in the circumferential direction. Between the compression wall portions 25, a pressure chamber 27, which is a fluid chamber for storing the fluid 4, is formed between the housing 10 and the rotating portion 3.

[0017] Furthermore, the housing 10 has a mounting portion 31 for attaching the rotary damper 1 to the mounting portion 30. The mounting portion 30 is, for example, a fixed-side member of the rotating mechanism. In the illustrated example, the mounting portion 30 is plate-shaped. The mounting portion 31 extends radially from, for example, the side wall portion 17, one or more times. The mounting portion 31 has a hole portion 32, and as shown in Figure 6, a support member 33 such as a pin is inserted into the hole portion 32, thereby supporting the rotary damper 1 in a state where it is prevented from rotating relative to the mounting portion 30.

[0018] The sealing member 11 shown in Figure 1 is also called a plug or the like. The sealing member 11 seals the fluid 4 inside the case body 2 by blocking the upper part of the housing 10 except for the rotating part 3. The sealing member 11 is formed in the shape of a plate. In this embodiment, the sealing member 11 is formed in the shape of a circular plate. A bearing part 35 is formed in the center of the sealing member 11. The bearing part 35 is formed in the shape of a cylinder. The bearing part 35, together with the bearing part 15 of the housing 10, is the part that sandwiches the rotating part 3 from above and below and supports it so that it can rotate.

[0019] The rotating part 3 shown in Figures 1 and 2 is also called a rotor. Part of the rotating part 3 is located inside the case body 2, while the remaining part is exposed from the case body 2. The rotating part 3 has a rotating part body 40, a compression part 41, and a connecting part 42 that connects the rotating part body 40 and the compression part 41.

[0020] The rotating part body portion 40 is the portion that is inserted through the bearing portions 15 and 35 of the case body 2 and is exposed from the case body 2. The rotating part body portion 40 is formed in a cylindrical shape with the rotation axis A as its central axis. In this embodiment, the upper end of the rotating part body portion 40 protrudes upward from the closing member 11. A shaft 44 is connected to the inner circumference of the rotating part body portion 40. The inner circumference of the rotating part body portion 40 is formed with a non-circular cross-section, for example, a hexagonal cross-section, so that the shaft 44 rotates together with the rotating part body portion 40 and rotates integrally with the rotating part 3.

[0021] The compression section 41, also called a movable vane, is a wall located inside the case body 2 that generates torque by compressing the fluid 4 between itself and the compression wall 25 of the case body 2. The compression section 41 is located outside the rotating section main body 40. The compression section 41 is located in the pressure chamber 27 and divides the pressure chamber 27 into one side and the other side. The compression section 41 extends radially with respect to the rotating section main body 40. The compression section 41 is formed in one or more units depending on the compression wall 25. In this embodiment, the compression sections 41 are arranged one on each side opposite to each other with respect to the rotation axis A. Annular sealing members 45 and 46, such as O-rings, are attached to the inner circumference of the compression section 41. The sealing members 45 and 46 close the gap between the rotating section 3 and the case body 2. The sealing members 45 and 46 are located below and above the connecting portion 42, respectively, and are sandwiched radially between the compression portion 41 and the bearing portions 15 and 35, and vertically sandwiched between the compression portion 41 and the housing 10 and the closing member 11.

[0022] The shaft 44 shown in Figures 1 and 4 is, for example, a rotating member that rotates relative to the fixed side of the rotating mechanism. The shaft 44 is a columnar body that is arranged coaxially on the rotation axis of the rotating side of the rotating mechanism, or forms the rotation axis of the rotating side of the rotating mechanism. The shaft 44 has a fitting portion 48 that is fitted to the inner circumference of the rotating part body 40 in a state that prevents it from rotating. The fitting portion 48 is formed in a columnar shape with an outer shape corresponding to the inner circumference of the rotating part body 40, in this embodiment it is a hexagonal shape, i.e., a hexagonal prism. A receiving portion 49 is formed at one end of the fitting portion 48 to receive the case body 2 or housing 10, in this embodiment it is a receiving portion 49 that receives the rotating part body 40. The receiving portion 49 is a columnar shape with an outer shape larger than the inner shape of the fitting portion 48 and the rotating part body 40, and in this embodiment it is formed in a cylindrical shape, for example.

[0023] The rotary damper 1 is constructed by attaching the rotating body portion 40 of the rotating portion 3, to which the sealing members 45 and 46 are attached, to the bearing portion 15 of the housing 10, placing the compression portion 41 in the pressure chamber 27, injecting the fluid 4 into the pressure chamber 27, then placing the closing member 11 over the housing 10, and with the rotating body portion 40 of the rotating portion 3 supported by the bearing portion 15, the upper end of the side wall portion 17 of the housing 10 is crimped and deformed to form a holding portion 23, and the closing member 11 is integrally fixed to the housing 10. In this state, the sealing members 45 and 46 are pressed against the bearing portion 15 of the housing 10 and the bearing portion 35 of the closing member 11, respectively, and the holding portion 23 is pressed against the sealing member 21, so that the pressure chamber 27 is held liquid-tight.

[0024] As shown in Figure 6, the rotary damper 1 is held in place by inserting a support member 33 into a hole 32 in a mounting portion 31 of the housing 10 and attaching it to the mounting portion 30, and as shown in Figure 1, the fitting portion 48 of the shaft 44 is inserted into the rotating portion body 40 of the rotating portion 3 to use it.

[0025] When the rotating side of the rotating mechanism rotates relative to the stationary side, the shaft 44 provided on the rotating side rotates relative to the mounting portion 30 provided on the stationary side, and accordingly, the rotating part 3 rotates around the rotation axis A relative to the case body 2. In the rotating part 3, in accordance with its rotation, the compression portion 41 shown in Figure 2 compresses the fluid 4 between itself and the compression wall portion 25 of the housing 10, and the compressed fluid 4 passes through the gap between the case body 2 and the rotating part 3 (fitting gap, and / or a gap intentionally formed for the passage of fluid 4), and / or through a flow path arbitrarily formed in the compression portion 41 of the rotating part 3 shown in Figure 1, etc., between one side and the other of the pressure chamber 27, and / or between the pressure chambers 27, 27. As a result, the pressure resistance of the fluid 4 passing through generates a large torque, the faster the rotating part 3 attempts to rotate.

[0026] In such a pressure-type rotary damper 1, when the internal pressure of the case body 2 is high, especially when the fluid 4 is compressed by the rotation of the rotating part 3 and the pressure rises, the closing member 11 is pushed up by this pressure in a range extending from a position inside the holding part 23 of the housing 10 to the bearing part 35, causing slight deformation. This creates unintended clearances between the compression part 41 of the rotating part 3 and the closing member 11, and between the closing member 11 and the housing 10, making it easier for the fluid 4 to pass between one side and the other of the pressure chamber 27, raising concerns that the desired torque performance may not be achieved.

[0027] Therefore, in this embodiment, the rotary damper 1 is equipped with a deformation restricting member 50 as an external fixing device for suppressing deformation of the closing member 11. The deformation restricting member 50 shown in Figures 1 and 3 is also called a nut, and is fastened to the shaft 44 and is a member that presses the closing member 11 against the internal pressure of the case body 2 in accordance with the rotation of the shaft 44. The deformation restricting member 50 has a main body portion 52 that is fastened to the shaft 44 and a pressing portion 53 that presses the closing member 11.

[0028] The main body portion 52 is formed in a block shape. The main body portion 52 has a fastening portion 54 in the center to which the shaft 44 is fastened. The fastening portion 54 is a female screw hole and is screwed into a male screw-shaped shaft connecting portion 55 which is formed coaxially with the shaft 44. In accordance with the tightening of the fastening portion 54 and the shaft connecting portion 55, the pressing portion 53 presses the closing member 11 downward. In the illustrated example, the main body portion 52 has a recessed portion 57 at the bottom to avoid interference with the rotating main body portion 40.

[0029] Furthermore, in this embodiment, the main body 52 has a shape that allows the deformation restricting member 50 to be tightened against the shaft 44 using a tool or jig such as a wrench, and has at least one pair of parallel or substantially parallel surfaces 58, 58 on opposite sides with respect to the rotation axis A. For example, the outer part of the main body 52 is formed in a hexagonal shape with three pairs of surfaces 58, 58 in the circumferential direction. That is, the main body 52 is hexagonal nut-shaped and also serves as a fastening work part to which external force is applied when fastening the deformation restricting member 50 to the shaft 44.

[0030] The pressing portion 53 is the part that contacts the closing member 11 and extends radially from the main body portion 52. In this embodiment, the pressing portion 53 extends in a flange shape from the lower end of the outer part of the main body portion 52 and is formed to extend continuously around the entire circumference of the main body portion 52. Therefore, the main body portion 52 is located on the outside of the pressing portion 53, opposite to the closing member 11. The deformation restricting member 50 is in the shape of a flange nut due to the main body portion 52 and the pressing portion 53. In the illustrated example, the pressing portion 53 is plate-shaped. The outer part of the pressing portion 53 is formed, for example, in a circular shape. The pressing portion 53 is positioned outside the bearing portion 35 of the closing member 11 and overlaps the position of the closing member 11 closer to the inner circumference.

[0031] The shaft connecting portion 55 is formed coaxially with the other end of the fitting portion 48 on the shaft 44. In this embodiment, for example, the shaft connecting portion 55 is shown as having a right-hand thread, but it is not limited to this and may also have a left-hand thread.

[0032] Preferably, the deformation restricting member 50 is provided with a co-rotation prevention mechanism 60 to prevent the deformation restricting member 50 from rotating together with the shaft 44. The co-rotation prevention mechanism 60 suppresses the rotation of the deformation restricting member 50 with respect to the rotation of the shaft 44 in the loosening direction relative to the fastening portion 54 of the deformation restricting member 50.

[0033] The anti-rotation mechanism 60 may be formed arbitrarily, but in this embodiment, for example, as shown in Figures 5(a) and 5(b), restricting portions 62 and 63 are formed on the closing member 11 and the pressing portion 53 of the deformation restricting member 50.

[0034] The restricting portion 62 is formed as a projection on the upper part of the closing member 11 facing the pressing portion 53. In this embodiment, the restricting portion 62 is a radially extending straight rib. The restricting portion 63 is formed as a projection on the lower part of the pressing portion 53 facing the closing member 11. In this embodiment, the restricting portion 63 is a radially extending straight rib. Multiple and equal numbers of restricting portions 62 and 63 are formed and are equally or substantially equally distributed in the circumferential direction.

[0035] As shown in Figure 5(c), the restricting portion 62 is formed in a substantially triangular cross-section, having an inclined surface 65 that gradually protrudes from the closing member 11 in the fastening direction, and a stopper surface 66 that extends vertically following the inclined surface 65. On the other hand, the restricting portion 63 is formed in a substantially triangular cross-section, having an inclined surface 68 that gradually protrudes from the pressing portion 53 of the deformation restricting member 50 in the loosening direction, and a stopper surface 69 that extends vertically following the inclined surface 68.

[0036] Therefore, the rotation of the shaft 44 in the fastening direction with respect to the fastening portion 54 of the deformation restricting member 50 is facilitated by the opposing inclined surfaces 65 and 68 of the restricting portions 62 and 63, while the rotation of the shaft 44 in the loosening direction with respect to the fastening portion 54 of the deformation restricting member 50 is restricted by the contact between the stopper surfaces 66 and 69 of the restricting portions 62 and 63.

[0037] The deformation restricting member 50 is then fastened to the shaft connecting portion 55 of the shaft 44 via the fastening portion 54, and the main body portion 52 is tightened until the pressing portion 53 comes into contact with the closing member 11.

[0038] When the shaft 44 rotates in the fastening direction, which in this embodiment is counterclockwise (clockwise) when viewed from the deformation restricting member 50 side, the deformation restricting member 50 fastened to the shaft 44 at the fastening portion 54 is tightened and pulled relatively toward the closing member 11, causing the pressing portion 53 to press the closing member 11 against the internal pressure of the case body 2. This suppresses deformation of the closing member 11 caused by the internal pressure of the case body 2. Therefore, it is possible to suppress slight deformation of the closing member 11 by pushing it up in the range from a position inside the holding portion 23 of the housing 10 to the bearing portion 35, and to suppress the formation of unintended clearances between the compression portion 41 of the rotating portion 3 and the closing member 11, and between the closing member 11 and the housing 10, so that the unintended passage of the fluid 4 is suppressed and the desired torque performance designed can be obtained.

[0039] Further, since the pressing portion 53 is a plate shape that extends continuously over the entire circumference, the closing member 11 can be pressed evenly over the entire circumference, and it is difficult for uneven deformation of the closing member 11 due to the internal pressure of the case body 2 to occur.

[0040] Also, when the shaft 44 rotates in the loosening direction opposite to the fastening direction, that is, clockwise (counterclockwise) as viewed from the deformation restricting member 50 side in the present embodiment, the co-rotation prevention mechanism 60 suppresses the deformation restricting member 50 from co-rotating with the shaft 44, and the fastening at the fastening portion 54 with respect to the shaft 44 is loosened. Therefore, when the shaft 44 rotates again in the fastening direction, the deformation restricting member 50 is tightened and pulled relatively toward the closing member 11 side, and the pressing portion 53 can press the closing member 11 against the internal pressure of the case body 2.

[0041] Therefore, the rotary damper 1 of the present embodiment can be suitably used particularly for a one-way rotary damper 1 in which the shaft 44 rotates at high speed in the fastening direction, that is, a one that generates a large torque when rotating in the fastening direction. The one-way rotary damper 1 can be realized by a known structure such as a structure in which a valve that restricts the flow in one direction and allows the flow in the other direction is provided in a gap or a flow path through which the fluid 4 passes, or a structure in which a one-way clutch is used in a portion that transmits the rotation of the shaft 44 to the rotating portion 3.

[0042] Note that the outer shape of the main body portion 52 of the deformation restricting member 50 is not limited to a hexagonal shape, and may be, for example, a circular shape or the like as in the second embodiment shown in FIG. 7.

[0043] Next, the third embodiment will be described with reference to FIG. 8. Regarding the same configurations and operations as those in the above embodiments, the same reference numerals are given and the description thereof is omitted.

[0044] In the deformation restricting member 50 of the present embodiment, a plurality of pressing portions 53 extend from the main body portion 52 in an arm shape.

[0045] The pressing portions 53 are arranged rotationally symmetrically with respect to the rotation axis line A, and are, for example, equally or substantially equally arranged in the circumferential direction of the deformation restricting member 50. In the present embodiment, four pressing portions 53 are provided in the circumferential direction. For example, the pressing portion 53 is formed in a crank shape integrally including an extending portion 70 extending radially from the main body portion 52, a leg portion 71 bent downward from the extending portion 70 and extending in the axial direction, and a contact portion 72 bent and extending radially from the leg portion 71.

[0046] The extending portion 70 protrudes from the side surface of the main body portion 52. In the present embodiment, the upper surface of the extending portion 70 is formed flush or substantially flush with the upper surface of the main body portion 52, for example.

[0047] In the illustrated example, the lower end portion of the leg portion 71 extends below the lower end portion of the main body portion 52. Therefore, at least the lower portion of the pressing portion 53 is located below the main body portion 52.

[0048] And this deformation restricting member 50 is fastened to the shaft connecting portion 55 of the shaft 44 via the fastening portion 54, and is attached by tightening until the contact portion 72 of the pressing portion 53 abuts against the closing member 11.

[0049] At this time, for example, by biting a jig, a tool, or the like between the pressing portions 53, 53, the deformation restricting member 50 can be easily fastened to the shaft 44.

[0050] Then, when the shaft 44 rotates in the fastening direction, counterclockwise (rightward) as viewed from the side of the deformation restricting member 50 in the present embodiment, the deformation restricting member 50 fastened to the shaft 44 by the fastening portion 54 is tightened and pulled relatively toward the closing member 11 side, and each pressing portion 53 presses the closing member 11 against the internal pressure of the case body 2. Therefore, the same operational effects as those of each embodiment can be achieved, such as suppressing the deformation of the closing member 11 caused by the internal pressure of the case body 2.

[0051] In addition, in the third embodiment, although an example in which the outer shape of the main body portion 52 has the same shape as that of the second embodiment has been given, the present invention is not limited to this, and for example, it may have an arbitrary shape such as the same shape as that of the first embodiment.

[0052] Next, a fourth embodiment will be described with reference to Figures 9 to 13. Note that components and operations similar to those in the above embodiments are denoted by the same reference numerals, and their descriptions are omitted.

[0053] In this embodiment, a portion of the main body 52 of the deformation restricting member 50 is housed inside the case body 2, thereby saving space.

[0054] As shown in Figure 9, the rotary damper 1 is formed such that the upper end of the rotating body portion 40 of the rotating portion 3 is lower than the upper end of the compression portion 41, and the upper end of the rotating body portion 40 is at the position of the lower end of the bearing portion 35 of the closing member 11. Therefore, a recessed space 75 is formed inside the bearing portion 35 of the closing member 11, below the upper surface of the closing member 11.

[0055] The main body 52 has an insertion portion 76 at the lower part of the pressing portion 53 that is inserted into the space 75. As shown in Figure 10(b), the insertion portion 76 is formed, for example, on its outer side in a circular shape. Also, as shown in Figure 9, the main body 52 has a projection 77 at the upper part of the pressing portion 53 that functions as a fastening work portion that allows the deformation restricting member 50 to be tightened against the shaft 44 using a tool or jig such as a wrench. The projection 77 is formed coaxially with the insertion portion 76, and a fastening portion 54 is formed extending from the center of the projection 77 to the center of the insertion portion 76. As shown in Figure 10(a), the projection 77 has a shape in which it has at least one pair of surfaces 78, 78 that are parallel or substantially parallel to each other, on opposite sides with respect to the axis of rotation A. For example, the outer part of the projection 77 is formed in a hexagonal shape with three pairs of surfaces 78, 78 in the circumferential direction. In other words, the protruding portion 77 is a hexagonal portion formed in the shape of a hexagonal nut.

[0056] Furthermore, in this embodiment, one of the restricting portions 62 and 63 of the anti-rotation mechanism 60 shown in Figure 9 is formed as a convex portion and the other as a concave portion. In the illustrated example, the restricting portion 62 is a concave portion and the restricting portion 63 is a convex portion, but the restricting portion 62 may be a convex portion and the restricting portion 63 may be a concave portion.

[0057] As shown in Figure 11, the restricting portion 62 is formed in the shape of a rectangular groove on the inner edge of the bearing portion 35 at the position of the upper surface of the closing member 11. In the illustrated example, four restricting portions 62 are formed and are equally or substantially equally distributed in the circumferential direction.

[0058] Furthermore, as shown in Figure 10(b), the restricting portion 63 is formed as a projection extending from the pressing portion 53 to the outer part of the insertion portion 76 at the lower surface of the pressing portion 53 of the deformation restricting member 50. There are four restricting portions 63 in this embodiment, the same number as the restricting portions 62, and they are equally or substantially equally distributed in the circumferential direction.

[0059] The deformation restricting member 50 is then fastened to the shaft connecting portion 55 of the shaft 44 via the fastening portion 54, with the insertion portion 76 of the main body portion 52 facing the closing member 11, and the protruding portion 77 of the main body portion 52 is tightened until the pressing portion 53 contacts the closing member 11. In this state, the restricting portion 63 of the deformation restricting member 50 is inserted into the restricting portion 62 of the closing member 11.

[0060] When the shaft 44 rotates in the fastening direction, which in this embodiment is counterclockwise (clockwise) when viewed from the deformation restricting member 50 side, the deformation restricting member 50 fastened to the shaft 44 by the fastening portion 54 is tightened and relatively pulled toward the closing member 11 side, causing the pressing portion 53 to press the closing member 11 against the internal pressure of the case body 2. As a result, the deformation of the closing member 11 caused by the internal pressure of the case body 2 can be suppressed, and the same effects as in each embodiment can be achieved.

[0061] Furthermore, when the shaft 44 rotates in a loosening direction opposite to the fastening direction, which in this embodiment is clockwise (counterclockwise) when viewed from the deformation restricting member 50 side, as shown in Figure 12, the restricting portion 63 of the co-rotation prevention mechanism 60 comes into contact with the restricting portion 62 in the circumferential direction, thereby suppressing the deformation restricting member 50 from rotating together with the shaft 44.

[0062] Furthermore, in this embodiment, as shown in Figures 9 and 13, the portion of the deformation restricting member 50 that protrudes outward is suppressed, making it possible to construct a more space-saving design.

[0063] Next, a fifth embodiment will be described with reference to Figures 14 to 16. Note that components and operations similar to those in the above embodiments are denoted by the same reference numerals, and their descriptions are omitted.

[0064] In this embodiment, the pressing portion 53 functions as a fastening work portion that allows the deformation restricting member 50 to be tightened against the shaft 44 using a tool or jig such as a wrench. As shown in Figure 15, the outer portion of the pressing portion 53 has a shape having at least one pair of surfaces 80, 80 that are parallel or substantially parallel to each other, on opposite sides with respect to the rotation axis A. For example, the outer portion of the pressing portion 53 is formed in a hexagonal shape having three pairs of surfaces 80, 80 in the circumferential direction. It is preferable that the pressing portion 53 has a thickness of a predetermined amount or more so that the deformation restricting member 50 can be tightened with a tool or jig.

[0065] Therefore, as shown in Figure 14, the main body portion 52 is equipped only with an insertion portion 76 that is inserted into the space portion 75 of the case body 2, and the deformation restricting member 50 has a shape that does not have a portion that protrudes upward relative to the pressing portion 53. In other words, the planar upper surface of the pressing portion 53 forms the upper part of the deformation restricting member 50.

[0066] The deformation restricting member 50 is then attached by fastening the insertion portion 76 of the main body portion 52 to the shaft connecting portion 55 of the shaft 44 via the fastening portion 54, with the insertion portion 76 of the main body portion 52 facing the closing member 11, and by tightening the pressing portion 53 until it comes into contact with the closing member 11.

[0067] When the shaft 44 rotates in the fastening direction, which in this embodiment is counterclockwise (clockwise) when viewed from the deformation restricting member 50 side, the deformation restricting member 50 fastened to the shaft 44 by the fastening portion 54 is tightened and relatively pulled toward the closing member 11 side, causing the pressing portion 53 to press the closing member 11 against the internal pressure of the case body 2. As a result, the deformation of the closing member 11 caused by the internal pressure of the case body 2 can be suppressed, and the same effects as in each embodiment can be achieved.

[0068] Furthermore, as shown in Figures 14 and 16, only the pressing portion 53 protrudes from the deformation restricting member 50, making it possible to construct a more space-saving design.

[0069] In the fourth and fifth embodiments, the anti-rotation mechanism 60 may have any configuration, for example, a configuration that includes a plurality of linear rib-shaped restricting parts 62 and 63, as in the first embodiment.

[0070] Furthermore, the anti-rotation mechanism 60 may be configured as in the sixth embodiment shown in Figures 17 to 19. In this embodiment, as shown in Figures 18(a) and 18(b), each restricting portion 62 is formed as a fan shape that expands radially, and the inclined surface 65 of one restricting portion 62 extends to the position of the stopper surface 66 of the adjacent restricting portion 62.

[0071] Similarly, as shown in Figures 17(a) and 17(b), each restricting portion 63 is formed as a fan shape that expands radially, and the inclined surface 68 of one restricting portion 63 extends to the position of the stopper surface 69 of the adjacent restricting portion 63.

[0072] Therefore, the restricting portions 62 and 63 each have a sawtooth shape in the circumferential direction, and the anti-rotation mechanism 60 is configured such that the restricting portions 62 and 63 interlock with each other in the circumferential direction.

[0073] Therefore, as shown in Figure 19(a), the rotation of the shaft 44 in the fastening direction with respect to the fastening portion 54 of the deformation restricting member 50 is restricted by the opposing inclined surfaces 65 and 68 of the restricting portions 62 and 63, which facilitates tightening of the deformation restricting member 50. As shown in Figure 19(b), the rotation of the shaft 44 in the loosening direction with respect to the fastening portion 54 of the deformation restricting member 50 is restricted by the contact of the stopper surfaces 66 and 69 of the restricting portions 62 and 63, thereby preventing the deformation restricting member 50 from rotating together with the shaft 44.

[0074] The present invention is suitably used, for example, as a damping device for reducing kinetic energy in a rotating mechanism.

[0075] 1 Rotary damper 2 Case body 3 Rotating part 4 Fluid 10 Housing 11 Closure member 44 Shaft 50 Deformation restricting member 52 Main body 53 Pressing part 54 Fastening part 60 Co-rotation prevention mechanism

Claims

1. A deformation restricting member for a rotary damper, used in a rotary damper comprising: a case body having a housing and a closing member; a rotating part rotatable relative to the case body; and a fluid sealed inside the case body between the housing and the closing member, for generating torque corresponding to the rotating part relative to the case body, the rotary damper deformation restricting member comprising: a main body having a fastening part fastened to a shaft integrally connected coaxially to the rotating part; and a pressing part integrally provided on the main body for pressing the closing member toward the housing side.

2. The deformation restricting member for a rotary damper according to claim 1, characterized in that it is used in a one-way rotary damper that generates torque when the shaft rotates in the fastening direction relative to the fastening portion.

3. A rotary damper comprising: a case body having a housing and a closing member; a rotating part rotatable relative to the case body; a fluid sealed inside the case body between the housing and the closing member, for generating torque corresponding to the rotation of the rotating part relative to the case body; and a deformation restricting member according to claim 1 or 2.

4. The rotary damper according to claim 3, characterized in that it is a one-way rotary damper that generates torque when the shaft rotates in the fastening direction relative to the fastening portion.

5. The rotary damper according to claim 3, characterized by comprising a mechanism to prevent the deformation restricting member from rotating together with the fastening portion due to the rotation of the shaft in the loosening direction.

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