Rotary damper

Abstract

To prevent a seal from falling from a seal groove.SOLUTION: A seal groove formed in a vane includes: a first groove formed on a first end surface of the vane which faces a first end wall closing one end of a fluid chamber; a second groove formed on a second end surface of the vane which faces a second end wall closing the other end of the fluid chamber; a third groove formed on an apical surface of the vane which faces a peripheral wall of the fluid chamber and connecting the first groove with the second groove; and a fourth groove extending in an axial direction on a border between the shaft and the vane and connecting the first groove with the second groove. A seal comprises: a seal portion (31) which is attached to the first to third grooves and seals a gap between the vane and the first end wall, a gap between the vane and the second end wall, and a gap between the vane and the peripheral wall; and a connecting portion (32) which is attached to the fourth groove and connects both ends of the seal portion.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a rotary damper. [Background technology]

[0002] Conventionally, a rotary damper is known that includes a fluid chamber formed around a shaft, a vane protruding from the shaft and installed in the fluid chamber, a seal groove formed in the vane, and a seal attached to the seal groove.

[0003] For example, Patent Document 1 listed below discloses a rotary damper in which the seal groove comprises a first groove formed in a first end face of the vane facing a first end wall closing one end of the fluid chamber, a second groove formed in a second end face of the vane facing a second end wall closing the other end of the fluid chamber, and a third groove formed in a tip face of the vane facing the peripheral wall of the fluid chamber and connecting the first groove and the second groove, and the seal is attached continuously to the first to third grooves (see Figure 3 of Patent Document 1).

[0004] However, in the rotary damper disclosed in Patent Document 1, since the seal is U-shaped, there is a risk that the seal may fall off from the seal groove when the rotary damper is assembled. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 9-49538 Summary of the Invention [Problem to be solved by the invention]

[0006] The problem to be solved by the present invention is to prevent the seal from falling off the seal groove. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention provides a fluid chamber formed around a shaft, a vane protruding from the shaft and installed in the fluid chamber, a seal groove formed in the vane, and a seal attached to the seal groove, the seal groove comprising a first groove formed in a first end face of the vane facing a first end wall closing one end of the fluid chamber, a second groove formed in a second end face of the vane facing a second end wall closing the other end of the fluid chamber, and a seal attached to a tip face of the vane facing a peripheral wall of the fluid chamber. a third groove formed in the shaft and connecting the first groove and the second groove, and a fourth groove extending in the axial direction at the boundary between the shaft and the vane and connecting the first groove and the second groove, wherein the seal comprises seal portions attached to the first to third grooves and sealing gaps formed between the vane and the first end wall, between the vane and the second end wall, and between the vane and the peripheral wall, and a connecting portion attached to the fourth groove and connecting both ends of the seal portions. Effect of the Invention

[0008] According to the present invention, the seal groove is configured to have a fourth groove extending axially at the boundary between the shaft and the vane and connecting the first groove and the second groove, and the seal is mounted in the fourth groove and is configured to have a connecting portion connecting both ends of the seal portion, thereby making it possible to effectively prevent the seal from falling off the seal groove. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a vertical cross-sectional view of a rotary damper according to an embodiment. [Diagram 2] FIG. 2 is a cross-sectional view of the rotary damper according to the embodiment. [Diagram 3] FIG. 3 is a perspective view of a rotor employed in the embodiment. [Figure 4] FIG. 4 is a plan view of the rotor employed in the embodiment. [Diagram 5]FIG. 5 is a bottom view of the rotor employed in the embodiment. [Figure 6] FIG. 6 is a front view of the seal employed in the embodiment. [Figure 7] FIG. 7 is a cross-sectional view showing a state in which the seal is installed in the seal groove. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to these embodiments. EXAMPLES

[0011] 1 and 2, the rotary damper according to the embodiment includes a housing 10, a rotor 20, and a seal 30.

[0012] The housing 10 includes a cylindrical peripheral wall 11, a partition wall 12 protruding from the peripheral wall 11, an upper wall 13 closing one end of the peripheral wall 11, and a lower wall 14 closing the other end of the peripheral wall 11. The partition wall 12 is a partition that separates two fluid chambers 40 formed in the housing 10.

[0013] The fluid chamber 40 is a space into which a liquid viscous fluid such as oil is injected, and is formed around the shaft 21 that constitutes the rotor 20. The fluid chamber 40 is divided into two chambers, a first chamber 41 and a second chamber 42, by the vane 22 that constitutes the rotor 20.

[0014] The rotor 20 includes a shaft 21 and vanes 22 protruding from the shaft 21. The shaft 21 is connected to an object that transmits a rotational force to the rotor 20. However, depending on the mode of use, there may be cases where the housing 10 rotates around the rotor 20. In this case, the shaft 21 is connected to an object that prevents the rotor 20 from rotating.

[0015] The vane 22 is disposed in the fluid chamber 40, and moves within the fluid chamber 40 by the rotation of the shaft 21. The vane 22 is formed with small holes 23 that penetrate the vane 22 in the rotation direction and through which the viscous fluid passes.

[0016] 3 to 5, the vane 22 is formed with a seal groove 24 consisting of a first groove 24a, a second groove 24b, a third groove 24c, and a fourth groove 24d.

[0017] The first groove 24a is formed in a first end surface 22a of the vane 22 that faces a first end wall (upper wall 13 constituting the housing 10) that closes one end of the fluid chamber 40.

[0018] The second groove 24b is formed in a second end surface 22b of the vane 22 that faces a second end wall (the lower wall 14 that constitutes the housing 10) that closes the other end of the fluid chamber 40.

[0019] The third groove 24c is formed in the tip surface 22c of the vane 22 facing the peripheral wall of the fluid chamber 40 (the peripheral wall 11 that constitutes the housing 10).

[0020] The first groove 24a and the second groove 24b, more specifically, one end of the first groove 24a and one end of the second groove 24b, are connected via a third groove 24c.

[0021] The fourth groove 24d is formed at the boundary between the shaft 21 and the vane 22 so as to extend in the axial direction.

[0022] The first groove 24a and the second groove 24b, more specifically, the other end of the first groove 24a and the other end of the second groove 24b, are connected via a fourth groove 24d.

[0023] A first end face 22a of the vane 22 is a flat surface. A second end face 22b of the vane 22 is also a flat surface like the first end face 22a. A tip face 22c of the vane 22 is a curved surface that connects to the first end face 22a and the second end face 22b.

[0024] The depths of the first groove 24a, the second groove 24b, and the third groove 24c are set to be uniform. Therefore, the bottom of the third groove 24c formed in the tip face 22c of the vane 22 is smoothly connected to the bottom of the first groove 24a formed in the first end face 22a of the vane 22. The bottom of the third groove 24c is also smoothly connected to the bottom of the second groove 24b formed in the second end face 22b of the vane 22.

[0025] Referring to FIG. 6, the seal 30 is made of an elastic material such as rubber, and is composed of a sealing portion 31 and a connecting portion 32.

[0026] The sealing portion 31 is a portion that is attached to the first groove 24a, the second groove 24b and the third groove 24c, and serves to seal the gaps formed between the vane 22 and the first end wall of the fluid chamber 40 (upper wall 13 that constitutes the housing 10), between the vane 22 and the second end wall of the fluid chamber 40 (lower wall 14 that constitutes the housing 10), and between the vane 22 and the peripheral wall of the fluid chamber 40 (peripheral wall 11 that constitutes the housing 10).

[0027] The connecting portion 32 is a portion that is attached to the fourth groove 24d, and serves to connect both ends of the sealing portion 31 together.

[0028] Referring to FIG. 7, the seal 30 is mounted to surround the vane 22 by a sealing portion 31 and a connecting portion 32 .

[0029] As described above, in the rotary damper according to the embodiment, the seal groove 24 extends in the axial direction at the boundary between the shaft 21 and the vane 22 and includes the fourth groove 24d connecting the first groove 24a and the second groove 24b. The seal 30 is attached to the fourth groove 24d and includes a connection portion 32 connecting both ends of the seal portion 31. Therefore, even if the seal portion 31 tries to fall off from the first groove 24a, the second groove 24b, or the third groove 24c when assembling the rotary damper, the seal portion 31 is held by the connection portion 32, and therefore the seal 30 can be effectively prevented from falling off from the seal groove 24.

[0030] Moreover, tension can be generated in the seal portion 31 by adjusting the length of the seal portion 31 and / or the length of the connection portion 32. In the embodiment, the seal portion 31 is attached to the first groove 24a, the second groove 24b, and the third groove 24c by the tension generated in the seal portion 31, so that it is possible to more effectively prevent the seal 30 from falling off the seal groove 24 when assembling the rotary damper.

[0031] Furthermore, since the bottom of the third groove 24c is smoothly connected to the bottom of the first groove 24a and the bottom of the second groove 24b, a uniform tension can be generated in the entire seal portion 31. Therefore, it is possible to more effectively prevent the seal 30 from falling off the seal groove 24 when assembling the rotary damper.

[0032] The rotary damper according to the embodiment operates as follows. That is, when the shaft 21 rotates in one direction (clockwise direction in FIG. 2), the vane 22 pressurizes the viscous fluid in the first chamber 41. At this time, the gaps formed between the vane 22 and the first end wall (upper wall 13 constituting the housing 10), between the vane 22 and the second end wall (lower wall 14 constituting the housing 10), and between the vane 22 and the peripheral wall of the fluid chamber 40 (peripheral wall 11 constituting the housing 10) are sealed by the seal portion 31 of the seal 30, so that the flow path for the viscous fluid in the first chamber 41 to move to the second chamber 42 is limited to the small hole 23 formed in the vane 22. As a result, the rotary damper generates a braking force that decelerates the rotation speed of the shaft 21.

[0033] When shaft 21 rotates in the reverse direction (counterclockwise in FIG. 2), vane 22 pressurizes the viscous fluid in second chamber 42. At this time, too, the sealing function of seal portion 31 limits the flow path for the viscous fluid in second chamber 42 to move to first chamber 41 to small hole 23 formed in vane 22. As a result, the rotary damper generates a braking force that decelerates the rotational speed of shaft 21.

[0034] In the embodiment, the small holes that generate resistance to the viscous fluid are formed in the vane, but such small holes may be formed in, for example, a partition wall. Also, instead of the small holes, a flow path that moves the viscous fluid without generating resistance to the viscous fluid may be formed in the partition wall or the like, and a valve may be installed in this flow path. For example, a check valve may be installed as the valve to make the rotary damper unidirectional. Alternatively, a load-responsive valve that can limit the flow rate of the viscous fluid in response to the magnitude of the force that rotates the rotor may be installed as the valve of the unidirectional rotary damper, thereby changing the magnitude of the braking force according to the load. [Explanation of symbols]

[0035] 10. Housing 11 Surrounding wall 12 Bulkhead 13 Upper wall 14 Lower wall 20 rotors 21 Shaft 22 Vane 22a First end surface 22b Second end face 22c Tip surface 23 small hole 24 Seal groove 24a First Groove 24b Second Groove 24c Third Groove 24d The Fourth Groove 30 Seals 31 Seal part 32 Connection part 40 Fluid chamber 41 Room 1 42 Room 2

Claims

1. The rotor includes a fluid chamber formed around a shaft, a vane protruding from the shaft and installed in the fluid chamber, a seal groove formed in the vane, and a seal attached to the seal groove, the seal groove comprises a first groove formed in a first end face of the vane facing a first end wall closing one end of the fluid chamber, a second groove formed in a second end face of the vane facing a second end wall closing the other end of the fluid chamber, a third groove formed in a tip face of the vane facing a peripheral wall of the fluid chamber and connecting the first groove and the second groove, and a fourth groove extending in the axial direction at a boundary between the shaft and the vane and connecting the first groove and the second groove, The rotary damper includes a seal portion that is fitted in the first to third grooves and seals gaps formed between the vane and the first end wall, between the vane and the second end wall, and between the vane and the peripheral wall, and a connecting portion that is fitted in the fourth groove and connects both ends of the seal portion.

2. 2. The rotary damper according to claim 1, wherein the seal portion is mounted in the first to third grooves by tension generated in the seal portion.

3. 2. The rotary damper according to claim 1, wherein the first and second end faces of the vane are flat, the tip face of the vane is a curved surface connected to the first and second end faces of the vane, the bottom of the third groove is smoothly connected to the bottom of the first groove and the bottom of the second groove, and the seal portion is attached to the first to third grooves by tension generated in the seal portion.

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