Rotary damper

Abstract

 The present invention provides a rotary damper characterized by comprising a cylinder (10) having partitions (13), a rotor (20) having a shaft (21) facing the partitions (13), grooves (15) formed in the partitions (13), and elastic bodies (40) provided in the grooves (15) to seal the gaps between the partitions (13) and the shaft (21) and characterized in that the groove (15) has a space (60) in which the elastic body (40) can move in the circumferential direction, and the space (60) has a section in which the elastic body (40) can be inserted without being compressed and a section in which the elastic body (40) can be accommodated by being compressed by a surface (15a) of the groove (15) that faces the shaft (21).

Description

Technical Field

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

Background Art

[0002] Conventionally, a rotary damper including a cylinder having a partition wall and a rotor having a shaft portion facing the partition wall has been known. However, in the conventional rotary damper, there has been a problem that oil flows out from the gap between the partition wall and the shaft portion. The outflow of oil from the gap between the partition wall and the shaft portion has contributed to the deterioration of the characteristics of the rotary damper.

[0003] WO 2003 / 046405 discloses a rotary damper including a cylinder having a partition wall, a rotor having a shaft portion facing the partition wall, a vane protruding from the shaft portion, an oil passage formed in the vane, and a valve that changes the flow rate of oil passing through the oil passage in one direction according to a load. This rotary damper has a characteristic that the operating time, that is, the time required for the rotor or the cylinder to rotate a certain rotation angle hardly changes due to a change in the load. However, there has been a problem that oil flows out from the gap between the partition wall and the shaft portion, and thus the characteristic deteriorates because an amount of oil sufficient for the valve to function is not supplied to the valve.

[0004] WO 2012 / 141242 discloses a rotary damper including a cylinder having a partition wall, a rotor having a shaft portion facing the partition wall, a vane protruding from the shaft portion, an oil passage formed in the vane, and a check valve provided in the oil passage. This rotary damper has a characteristic that a braking force is generated only when the rotor is rotated in one direction. However, there has been a problem that the braking force decreases because oil flows out from the gap between the partition wall and the shaft portion.

Prior Art Documents

Patent Documents

[0005] Patent Document 1 International Publication No. 2003 / 046405 Patent Document 2 International Publication No. 2012 / 141242 SUMMARY OF THE INVENTION PROBLEM TO BE SOLVED BY THE INVENTION

[0006] An object of the present invention is to prevent the outflow of oil from the gap between the partition wall and the shaft portion, and to facilitate the attachment of an elastic body for sealing the gap between the partition wall and the shaft portion. MEANS FOR SOLVING THE PROBLEM

[0007] To solve the above problems, the present invention provides the following rotary damper. 1. A cylinder having a partition wall, A rotor having a shaft portion facing the partition wall, A groove formed in the partition wall, and An elastic body installed in the groove to seal the gap between the partition wall and the shaft portion Regardless of the oil flow direction is provided, The groove has a space that allows the elastic body to move in the circumferential direction, The space has A portion (hereinafter referred to as "insertion portion") into which the elastic body can be inserted without being compressed, and A portion (hereinafter referred to as "accommodation portion") that accommodates the elastic body compressed by the surface of the groove facing the shaft portion has A rotary damper characterized by that. 2. A cylinder having a partition wall, A rotor having a shaft portion facing the partition wall, A groove formed in the partition wall, and An elastic body installed in the groove to seal the gap between the partition wall and the shaft portion is provided, ​The groove has a space that allows the elastic body to move in the circumferential direction, and the space has an insertion portion, and accommodation portions disposed on both sides of the insertion portion and is characterized by a rotary damper. A rotary damper characterized by the above. 3. A cylinder having a partition wall, a rotor having a shaft portion facing the partition wall, a groove formed in the partition wall, and an elastic body installed in the groove to seal the gap between the partition wall and the shaft portion is provided, the groove has a space that allows the elastic body to move in the circumferential direction, and the space has an insertion portion, and accommodation portions disposed on both sides of the insertion portion and is characterized by a rotary damper. A rotary damper characterized in that a surface of the groove facing the shaft portion is a curved surface. A rotary damper characterized by the above.

Advantages of the Invention

[0008] In the present invention described in the above 1 to 3 , since the groove has a space that allows the elastic body to move in the circumferential direction and the space has accommodation portions, it is possible to prevent the outflow of oil from the gap between the partition wall and the shaft portion. Further, since the space has an insertion portion, it is possible to facilitate the attachment of the elastic body. In the present invention described in the above 2 and 3, since the accommodation portions are disposed on both sides of the insertion portion, it is possible to prevent the outflow of oil flowing not only in one direction but also in the reverse direction from the gap between the partition wall and the shaft portion. In the present invention described in the above 3, since the surface of the groove facing the shaft portion is a curved surface, it is possible to quickly generate a sealing effect on the oil flowing in one direction and the reverse direction in the gap between the partition wall and the shaft portion.

Brief Description of the Drawings

[0009]

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MODE FOR CARRYING OUT THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

EXAMPLE

[0011] As shown in FIG. 1, the rotary damper according to Embodiment 1 includes a cylinder 10 and a rotor 20. The cylinder 10 is a cylindrical component that houses oil inside. The rotor 20 is a rotating component. However, the rotor 20 may not rotate in some cases. When the cylinder 10 is fixed so as not to rotate and the rotor 20 is rotated in one direction, that is, the clockwise direction in FIG. 4, the braking action, and when the rotor 20 is fixed so as not to rotate and the cylinder 10 is rotated in the reverse direction, that is, the counterclockwise direction in FIG. 4, the braking action is the same.

[0012] As shown in FIGS. 2, 3, and 4, the cylinder 10 has a peripheral wall 11, an end wall 12 that closes one end of the peripheral wall 11, and a partition wall 13 that protrudes from the peripheral wall 11 toward the center. As shown in FIGS. 1, 3, and 4, the cylinder 10 has a flange 14 that projects from the peripheral wall 11. The flange 14 is connected to a component that fixes the cylinder 10 so as not to rotate or a component that rotates the cylinder 10. As shown in FIGS. 1, 2, and 3, the other end of the peripheral wall 11 is closed by a lid 30. The lid 30 is attached to the cylinder 10 by caulking the end of the peripheral wall 11. As shown in FIGS. 2 and 4, a groove 15 is formed in the tip surface of the partition wall 13. The groove 15 is a seal groove, and as shown in FIGS. 2 and 4, an elastic body 40 that functions as a seal is installed in the groove 15. The elastic body 40 employed in Embodiment 1 is a cylindrical rubber.

[0013] As shown in FIGS. 2 and 4, the rotor 20 has a shaft portion 21 that faces the partition wall 13. The rotor 20 is installed so that the shaft portion 21 can rotate inside the cylinder 10. As shown in FIGS. 2 and 3, one end of the rotor 20 is inserted into a hole formed in the end wall 12, and the other end of the rotor 20 is inserted into a hole formed in the lid 30. As shown in FIGS. 1, 2, 3, and 4, a hole 22 into which a component that rotates the rotor 20 or a component that fixes the rotor 20 so as not to rotate is inserted is formed in the rotor 20. As shown in FIGS. 3 and 4, the rotor 20 has a vane 23 that projects from the shaft portion 21.

[0014] As shown in FIG. 4, inside the cylinder 10, four oil chambers partitioned by the partition wall 13 and the vane 23, namely, the first oil chamber 51, the second oil chamber 52, the third oil chamber 53, and the fourth oil chamber 54, are formed. Oil is injected into each of the oil chambers 51 to 54.

[0015] The rotary damper according to Embodiment 1 has a space 60 in which the groove 15 can move the elastic body 40 in the circumferential direction. That is, as shown in FIG. 5, the groove 15 forms a space 60 having a depth D and a width W that are longer than the diameter d of the elastic body 40 between the groove 15 and the shaft portion 21. As shown in FIG. 6, this space 60 has an insertion portion 61 and accommodation portions 62 disposed on both sides of the insertion portion 61. The insertion portion 61 is a portion in the space 60 into which the elastic body 40 can be inserted without being compressed. The accommodation portion 62 is a portion in the space 60 that accommodates the elastic body 40 compressed by the surface 15a of the groove 15 facing the shaft portion 21. As shown in FIG. 6, the surface 15a of the groove 15 facing the shaft portion 21 is a curved surface.

[0016] In the rotary damper according to Embodiment 1, when the rotor 20 rotates in one direction (clockwise direction in FIG. 4) or the cylinder 10 rotates in the reverse direction (counterclockwise direction in FIG. 4), the oil in the first oil chamber 51 flows from the gap between the partition wall 13 and the shaft portion 21 into the groove 15. Thereby, the elastic body 40 moves to the accommodation portion 62 while being compressed by the surface 15a of the groove 15 facing the shaft portion 21 and comes into close contact with the shaft portion 21 as shown in FIG. 7. As a result, the gap between the partition wall 13 and the shaft portion 21 is sealed. Therefore, according to the rotary damper according to Embodiment 1, it is possible to prevent the outflow of oil flowing in one direction from the gap between the partition wall 13 and the shaft portion 21.

[0017] In addition, in the rotary damper according to the first embodiment, when the rotor 20 rotates in the reverse direction (counterclockwise direction in FIG. 4) or the cylinder 10 rotates in one direction (clockwise direction in FIG. 4), the oil in the second oil chamber 52 flows into the groove 15 from the gap between the partition wall 13 and the shaft portion 21. As a result, the elastic body 40 moves toward the accommodating portion 62 while being compressed by the surface 15a facing the shaft portion 21 of the groove 15, and comes into close contact with the shaft portion 21 as shown in FIG. 8. As a result, the gap between the partition wall 13 and the shaft portion 21 is sealed. Therefore, according to the rotary damper according to the first embodiment, it is also possible to prevent the outflow of the oil flowing in the reverse direction from the gap between the partition wall 13 and the shaft portion 21.

[0018] When the groove 15 formed on the tip surface of the partition wall 13 has a depth or width shorter than the diameter of the elastic body 40, the elastic body 40 has to be installed in the groove 15 while being compressed, so that it is difficult to attach the elastic body 40. However, since the rotary damper according to the first embodiment has the insertion portion 61, the elastic body 40 can be installed in the groove 15 without being compressed. Therefore, according to the rotary damper according to the first embodiment, the elastic body 40 can be easily attached. Further, in the rotary damper according to the first embodiment, since the accommodating portion 62 is arranged on both sides of the insertion portion 61, it is possible to prevent not only the outflow of the oil flowing in one direction but also the outflow of the oil flowing in the reverse direction from the gap between the partition wall 13 and the shaft portion 21. Furthermore, in the rotary damper according to the first embodiment, since the surface 15a facing the shaft portion 21 of the groove 15 is a curved surface, a sealing effect can be quickly generated on the oil flowing in one direction and the reverse direction in the gap between the partition wall 13 and the shaft portion 21.

Embodiment

[0019] The rotary damper according to the second embodiment has the same configuration as the rotary damper according to the first embodiment, except that the groove 15' is different from the groove 15 adopted in the first embodiment.

[0020] The groove 15' of the rotary damper according to Example 2 has a space 60' that can move the elastic body 40 in the circumferential direction, similar to the groove 15 employed in Example 1. That is, as shown in FIG. 9, the groove 15' forms a space 60' having a depth D and a width W that are longer than the diameter d of the elastic body 40 between the shaft portion 21. This space 60' has an insertion portion 61' and a housing portion 62', but as shown in FIG. 10, it is different from Example 1 in that the housing portion 62' is installed on one side of the insertion portion 61', while the housing portion 62 is arranged on both sides of the insertion portion 61. The insertion portion 61' is the portion in the space 60' where the elastic body 40 can be inserted without being compressed. The housing portion 62' is the portion in the space 60' that houses the elastic body 40 compressed by the surface 15a' facing the shaft portion 21 of the groove 15'. Also, as shown in FIG. 10, it is different from Example 1 in that the surface 15a' facing the shaft portion 21 of the groove 15' is an inclined surface.

[0021] In the rotary damper according to Example 2, when the rotor 20 rotates in one direction or the cylinder 10 rotates in the reverse direction, the oil in the first oil chamber 51 flows into the groove 15' from the gap between the partition wall 13 and the shaft portion 21. Thereby, the elastic body 40 moves to the housing portion 62' while being compressed by the surface 15a' facing the shaft portion 21 of the groove 15', and adheres to the shaft portion 21 as shown in FIG. 11. As a result, the gap between the partition wall 13 and the shaft portion 21 is sealed. Therefore, according to the rotary damper according to Example 2, it is possible to prevent the outflow of the oil flowing in one direction from the gap between the partition wall 13 and the shaft portion 21.

[0022] On the other hand, when the oil in the second oil chamber 52 flows into the groove 15' from the gap between the partition wall 13 and the shaft portion 21 when the rotor 20 rotates in the reverse direction or the cylinder 10 rotates in one direction, as shown in FIG. 9, the elastic body 40 moves to the insertion portion 61'. At this time, since the elastic body 40 is not compressed, it does not adhere to the shaft portion 21. Therefore, the oil flowing in the reverse direction through the gap between the partition wall 13 and the shaft portion 21 flows out to the first oil chamber 51.

[0023] Since the rotary damper according to Example 2 has the insertion portion 61', it can be installed in the groove 15' without compressing the elastic body 40. Therefore, according to the rotary damper according to Example 2, the elastic body 40 can be easily attached. Further, since the accommodating portion 62' of the rotary damper according to Example 2 is installed on one side of the insertion portion 61', it is possible to prevent the outflow of oil flowing in one direction through the gap between the partition wall 13 and the shaft portion 21, while allowing the oil flowing in the reverse direction to flow out. Furthermore, since the surface 15a' of the groove 15' facing the shaft portion 21 of the rotary damper according to Example 2 is an inclined surface, a sealing effect can be quickly generated for the oil flowing in one direction through the gap between the partition wall 13 and the shaft portion 21.

Example

[0024] The rotary damper according to Example 3 has the same configuration as the rotary damper according to Example 2, except that it is provided with the oil passage 16.

[0025] Similar to the grooves 15 and 15' employed in Example 1 and Example 2, the groove 15'' of the rotary damper according to Example 3 has a space 60'' in which the elastic body 40 can be moved in the circumferential direction. That is, as shown in FIG. 12, the groove 15'' forms a space 60'' having a depth D and a width W that are longer than the diameter d of the elastic body 40 between the groove 15'' and the shaft portion 21. This space 60'' has an insertion portion 61'' and an accommodating portion 62'', but as shown in FIG. 13, it is the same as Example 2 in that the accommodating portion 62'' is installed on one side of the insertion portion 61''. The insertion portion 61'' is a portion in the space 60'' into which the elastic body 40 can be inserted without being compressed. The accommodating portion 62'' is a portion in the space 60'' that accommodates the elastic body 40 compressed by the surface 15a'' facing the shaft portion 21 of the groove 15''. Also, as shown in FIG. 13, the point that the surface 15a'' of the groove 15'' facing the shaft portion 21 is an inclined surface is the same as in Example 2.

[0026] The rotary damper according to Embodiment 3 is different from the rotary damper according to Embodiment 2 and includes an oil passage 16. As shown in FIG. 13, the oil passage 16 is formed in the partition wall 13 in order to communicate the oil chamber (first oil chamber 51) adjacent to the partition wall 13 with the insertion portion 61".

[0027] In the rotary damper according to Embodiment 3, when the rotor 20 rotates in one direction or the cylinder 10 rotates in the reverse direction, the oil in the first oil chamber 51 flows into the groove 15" from the gap between the partition wall 13 and the shaft portion 21. Thereby, the elastic body 40 moves to the accommodating portion 62" while being compressed by the surface 15a" facing the shaft portion 21 of the groove 15", and adheres to the shaft portion 21 as shown in FIG. 14. As a result, the gap between the partition wall 13 and the shaft portion 21 is sealed. Therefore, according to the rotary damper according to Embodiment 3, it is possible to prevent the outflow of the oil flowing in one direction through the gap between the partition wall 13 and the shaft portion 21.

[0028] On the other hand, when the oil in the second oil chamber 52 flows into the groove 15" from the gap between the partition wall 13 and the shaft portion 21 when the rotor 20 rotates in the reverse direction or the cylinder 10 rotates in one direction, as shown in FIG. 12, the elastic body 40 moves to the insertion portion 61". At this time, since the elastic body 40 is not compressed, it does not adhere to the shaft portion 21. Therefore, the oil flowing in the reverse direction through the gap between the partition wall 13 and the shaft portion 21 flows out to the first oil chamber 51 through the gap between the partition wall 13 and the shaft portion 21 and the oil passage 16.

[0029] The rotary damper according to Embodiment 3 has an insertion portion 61", and thus can be installed in the groove 15" without compressing the elastic body 40. Therefore, according to the rotary damper according to Embodiment 3, the elastic body 40 can be easily attached. Further, in the rotary damper according to Embodiment 3, since the accommodation portion 62" is installed on one side of the insertion portion 61", it is possible to prevent the outflow of oil flowing in one direction through the gap between the partition wall 13 and the shaft portion 21, while allowing the oil flowing in the reverse direction to flow out. Further, in the rotary damper according to Embodiment 3, since the surface 15a" facing the shaft portion 21 of the groove 15" is an inclined surface, a sealing effect can be quickly generated on the oil flowing in one direction through the gap between the partition wall 13 and the shaft portion 21. Furthermore, in the rotary damper according to Embodiment 3, when the oil flows in the reverse direction through the gap between the partition wall 13 and the shaft portion 21, the oil can be made to flow out to the first oil chamber 51 through the oil passage 16, so that the resistance of the oil acting on the vane 23 or the partition wall 13 can be reduced.

[0030] By applying the valve described in International Publication No. 2003 / 046405 to the rotary dampers according to Embodiments 1 to 3, it is possible to provide a rotary damper further including an oil passage formed in a vane and a valve that changes the flow rate of oil passing through the oil passage in one direction according to a load. "Oil passing through the oil passage in one direction" means oil moving from the first oil chamber to the fourth oil chamber via the oil passage and oil moving from the third oil chamber to the second oil chamber via the oil passage. "Flow rate of oil" means the amount of oil passing through the oil passage per unit time. "Load" means a force for rotating the rotor in one direction, that is, in the clockwise direction in FIG. 4, or a force for rotating the cylinder in the reverse direction, that is, in the counterclockwise direction in FIG. 4. "Change" means reducing the flow rate of oil in accordance with an increase in the load.

[0031] Since the rotary damper according to Embodiment 1 to Embodiment 3 can prevent the oil from flowing out from the gap between the partition wall and the shaft portion, it is possible to sufficiently supply oil to the valve. Therefore, it is possible to make the variation range of the operation time (that is, the time required for the rotor to rotate a certain rotation angle in one direction or for the cylinder to rotate a certain rotation angle in the reverse direction) caused by the change in the load smaller than that of the prior art.

[0032] By applying the valve described in International Publication No. 2012 / 141242 to the rotary damper according to Embodiment 1 to Embodiment 3, it is possible to provide a rotary damper further including an oil passage formed in the vane and a check valve provided in the oil passage.

[0033] Since the rotary damper according to Embodiment 1 to Embodiment 3 can prevent the oil from flowing out from the gap between the partition wall and the shaft portion, it is possible to make the braking force generated when the check valve closes the oil passage formed in the vane larger than that of the prior art. Further, since the rotary damper according to Embodiment 3 includes an oil passage formed in the partition wall, it is possible to make the resistance of the oil acting on the vane or the partition wall smaller than that of the prior art when the check valve opens the oil passage formed in the vane.

Explanation of Reference Numerals

[0034] 10 Cylinder 11 Peripheral Wall 12 End Wall 13 Partition Wall 14 Flange 15, 15’, 15” Groove 15a, 15a’, 15a” Surface Opposite to the Shaft Portion of the Groove 16 Oil Passage 20 Rotor 21 Shaft Portion 22 Hole 23 Vane 30 Lid 40 Elastic Body 51 First Oil Chamber 52 Second Oil Chamber 53 Third Oil Chamber 54 Fourth Oil Chamber 60, 60’, 60” space 61, 61’, 61” insertion part 62, 62’, 62” accommodation part

Claims

1. A cylinder having a partition wall, A rotor having a shaft portion facing the partition wall, A groove formed in the partition wall, and An elastic body installed in the groove to seal the gap between the partition wall and the shaft portion regardless of the oil flow direction are provided, the groove has a space capable of moving the elastic body in the circumferential direction, the space has a portion (hereinafter referred to as the "insertion portion") into which the elastic body can be inserted without being compressed, and a portion (hereinafter referred to as the "accommodation portion") that accommodates the elastic body compressed by the surface of the groove facing the shaft portion and has a rotary damper characterized by this.

2. The accommodation portion is arranged on both sides of the insertion portion The rotary damper according to claim 1, characterized by this.

3. The accommodation portion is arranged on both sides of the insertion portion, the surface of the groove facing the shaft portion is a curved surface The rotary damper according to claim 1, characterized by this.

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