Damper device

Abstract

A damper device is provided in which a piston is less likely to be withdrawn in a direction opposite to a direction of movement of the piston due to pressure in a cylinder chamber in the case of rapid movement of the piston. The piston of the damper device has a column portion around which a seal ring is wound, a first restriction portion and a second restriction portion located at both axial end sides of the column portion and formed so as to project radially outward beyond an outer peripheral surface of the column portion, and restrict movement of the seal ring in the axial direction. The column portion has a projection portion projecting radially outward from the outer peripheral surface. The first restriction portion has a notch portion formed so as to cut a surface opposite to the second restriction portion, and located at a position connected to the projection portion in the axial direction. The seal ring is arranged so as to be able to seal the second restriction portion, and is able to be deformed so as to partially enter the notch portion by movement of the piston. The seal ring is pressed against an inner peripheral surface of the cylinder by the projection portion in a state in which the seal ring is deformed and in a normal state in which the seal ring does not enter the notch portion.

Description

TECHNICAL FIELD

[0001] The present application relates to a damper device provided with a piston capable of advancing and retreating in a cylinder, and a seal ring provided on the outer periphery of the piston. BACKGROUND

[0002] Patent Document 1 discloses an air damper provided with a cylindrical cylinder, a piston that moves in the cylinder, and a cap provided at one end of the cylinder. The piston has a circular ring-shaped seal protrusion instead of an O-ring. The cap forms a throttle hole that connects the cylinder chamber with the outside.

[0003] PRIOR ART DOCUMENTS

[0004] PATENT DOCUMENT

[0005] Patent Document 1: Japanese Patent Application Publication No. 2000-65116

[0006] In the technology disclosed in Patent Document 1, in the case where the piston moves rapidly, sometimes the movement of the air in the cylinder chamber does not occur moderately from the throttle hole, and the piston retreats in the opposite direction due to the pressure of the cylinder chamber. SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] An object of the present application is to provide a damper device in which, in the case where the piston moves rapidly, the piston is less likely to retreat in the opposite direction to the direction in which the piston moves due to the pressure in the cylinder chamber.

[0009] SOLUTION TO PROBLEM

[0010] To solve the above problem, a damper device according to one aspect of the present application is provided with a cylinder having a bottom and an opening portion, a piston capable of advancing and retreating in the cylinder in the axial direction, and a seal ring provided on the outer periphery of the piston and abutting against the inner periphery of the cylinder. The piston has a column portion that is wrapped by the seal ring, and first and second restriction portions located on both axial end sides of the column portion and formed so as to project radially outward from the outer peripheral surface of the column portion, and restrict the movement of the seal ring in the axial direction. The column portion has a protruding portion that projects radially outward from the outer peripheral surface. The first restriction portion has a notch portion formed so as to cut the surface opposite to the second restriction portion, and located at a position connected to the protruding portion in the axial direction. The seal ring is configured to be capable of sealing the second restriction portion, and to be deformed so as to partially enter the notch portion by the movement of the piston. The seal ring is pressed against the inner peripheral surface of the cylinder by the protruding portion in the case where the seal ring is in a deformed state and in the case where the seal ring is in a normal state in which the seal ring does not enter the notch portion.

[0011] EFFECT OF THE INVENTION

[0012] According to the present application, a damper device can be provided in which the piston is not easily returned in the direction opposite to the direction of movement of the piston due to the pressure in the cylinder chamber in the case of rapid movement of the piston. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 is an exploded view of the damper device of the embodiment.

[0014] Figure 2 is an exploded view of the damper device of the embodiment.

[0015] Figure 3 (a) of FIG. 1 is a side view of the transmission portion and the piston, Figure 3 (b) of FIG. 1 is Figure 3 is a cross-sectional view at line A-A of the piston shown in (a) of FIG. 1.

[0016] Figure 4 (a) of FIG. 2 is a front view of the seal ring, Figure 4 (b) of FIG. 2 is Figure 4 is a cross-sectional view at line B-B of the seal ring shown in (a) of FIG. 2, Figure 4 (c) of FIG. 2 is Figure 4 (b) of FIG. 2 is a partial enlarged view of the seal ring shown in (b) of FIG. 2.

[0017] Figure 5 is a cross-sectional view of the damper device at a position through the piston.

[0018] Figure 6 (a) of FIG. 3 and Figure 6 (b) of FIG. 3 are diagrams for explaining the action of the seal ring, and are cross-sectional views of the piston portion of the damper device.

[0019] Figure 7 is a side view of the seal ring and the piston, and is a diagram showing the state in which the seal ring enters the notch portion of the piston.

[0020] BRIEF DESCRIPTION OF DRAWINGS

[0021] 10 damper device; 12 cylinder; 14 transmission portion; 16 guide portion; 18 cover; 20 seal ring; 22 piston; 24 column portion; 26 first restriction portion; 28 second restriction portion; 30 outer peripheral surface; 31 recessed portion; 32 protruding portion; 33 circular-arc portion; 34 notch portion; 36 first shaft support portion; 38 second shaft support portion; 40 bottom portion; 42 opening portion; 44 holding portion; 46 locking hole; 50 trunk portion; 50a axial end portion; 52 first lip portion; 54 second lip portion. DETAILED DESCRIPTION

[0022] Figure 1 is a perspective view of the damper device 10 of the embodiment. Furthermore, Figure 2is an exploded view of the damper device 10 of the embodiment. The damper device 10 is fitted to, for example, a glove box of a vehicle, and gives a damping force to the opening and closing operation of a lid member that is an opening and closing body of the glove box. Also, the damper device 10 can be fitted to a console box of a vehicle, and gives a damping force to the opening and closing of a lid member that is an opening and closing body of the console box. The glove box and the console box function as a fixed body, and the damper device 10 is linked to the fixed body and the opening and closing body that opens and closes an opening of the fixed body.

[0023] The damper device 10 has a cylinder 12, a transmission portion 14, a guide portion 16, a lid 18, a seal ring 20, and a piston 22. The damper device 10 uses air as a viscous fluid to generate a viscous resistance.

[0024] The cylinder 12 has a first shaft support portion 36, a bottom portion 40, an opening portion 42, a holding portion 44, and a locking hole 46. The cylinder 12 is formed in a cylindrical shape, has the bottom portion 40 at one end thereof, and has the opening portion 42 at the other end thereof. The first shaft support portion 36 protrudes from the outer circumferential surface of the cylinder 12 to the radial direction outside, has a through-hole into which one of the fixed body and the opening and closing body is inserted, and supports a shaft to one of the fixed body and the opening and closing body.

[0025] The holding portion 44 is formed in the bottom portion 40, and holds the lid 18. The locking hole 46 is formed in the inner circumferential surface of the cylinder 12, and locks the guide portion 16.

[0026] The transmission portion 14 is formed in a bar shape, and is inserted from the opening portion 42 of the cylinder 12. The transmission portion 14 transmits an external force to the piston 22. The transmission portion 14 has a second shaft support portion 38 that supports a shaft to the other of the fixed body and the opening and closing body. The second shaft support portion 38 has a through-hole into which the other of the fixed body and the opening and closing body is inserted. The through-hole of the first shaft support portion 36 is parallel to the through-hole of the second shaft support portion 38.

[0027] The guide portion 16 is fitted to the opening portion 42 of the cylinder 12, and guides the advance and retreat of the transmission portion 14. The guide portion 16 has a guide hole 16a into which the transmission portion 14 is inserted, and a locking claw 16b that is locked to the locking hole 46 of the cylinder 12.

[0028] The lid 18 is fitted to the bottom portion 40 by the holding portion 44, has a minute hole that becomes a throttle hole, and forms the throttle hole on the side of the bottom portion 40 of the cylinder 12.

[0029] The seal ring 20 is provided to the outer circumference of the piston 22, divides the inside of the cylinder 12 into a first chamber and a second chamber, and abuts against the inner circumference of the cylinder 12. The seal ring 20 is formed of a rubber material, and is deformable.

[0030] The piston 22 is provided to one end of the transmission portion 14, is disposed in the cylinder 12, and is advanceable and retreatable in the axial direction in the cylinder 12. The piston 22 is integrated with the transmission portion 14.

[0031] Figure 3 (a) is a side view of the delivery portion 14 and the piston 22, Figure 3 (b) is Figure 3 (a) is a cross-sectional view at a line segment A-A of the piston 22 shown in (a). The piston 22 has a column portion 24, a first restriction portion 26, and a second restriction portion 28.

[0032] The first restriction portion 26 and the second restriction portion 28 are located at both axial ends of the column portion 24, and are formed so as to project radially outward of an outer peripheral surface 30 of the column portion 24. The first restriction portion 26 and the second restriction portion 28 restrict axial movement of the seal ring 20 wound around the column portion 24 when the piston 22 is advanced and retracted.

[0033] The first restriction portion 26 has a notch portion 34 formed by being recessed in the axial direction. As shown in (a) of Figure 3 , the notch portion 34 is formed on a surface opposite the second restriction portion 28. End portions 34a of both sides of the notch portion 34 are formed in a stepped shape, and have a prescribed angular width, for example, an angular width of 120 degrees. The seal ring 20 is able to deform in such a manner that a portion enters the notch portion 34 by the notch portion 34. The surface of the second restriction portion 28 opposite the first restriction portion 26 is uniform, and is not formed with a notch.

[0034] The column portion 24 is located between the first restriction portion 26 and the second restriction portion 28. The column portion 24 is formed in a cylindrical shape, and has a recessed portion 31, a protruding portion 32, and a circular arc portion 33 on the outer peripheral surface 30. The protruding portion 32 is formed so as to protrude radially outward of the outer peripheral surface 30, and the recessed portion 31 is formed so as to be recessed to both sides in the circumferential direction of the protruding portion 32. The circular arc portion 33 occupies more than half of the outer peripheral surface 30 of the column portion 24, and is formed smoothly.

[0035] As shown in (b) of Figure 3 , the protruding portion 32 protrudes radially outward of an inscribed circle 33a of the circular arc portion 33. Thus, the seal ring 20 wound around the column portion 24 abuts against the protruding portion 32.

[0036] The protruding portion 32 is formed from the second restriction portion 28 to the notch portion 34 of the first restriction portion 26. The notch portion 34 is formed in such a manner that a cut is made to an opposite surface of the first restriction portion 26 opposite the second restriction portion 28, and is located at a position connected to the protruding portion 32 in the axial direction. In the circumferential position, the protruding portion 32 is located between the end portions 34a of both sides of the notch portion 34. Thus, the seal ring 20 is able to deform into the notch portion 34 side while maintaining the state of abutting against the protruding portion 32 as is.

[0037] The protrusion 32 protrudes in the axial direction of the first shaft support portion 36 and the second shaft support portion 38. Thus, the protrusion 32 can be disposed at a position that is less likely to be affected by an external force input from the first shaft support portion 36 and the second shaft support portion 38, and in the event that the piston 22 is eccentric due to an external force, the protrusion 32 can be inhibited from moving away from the inner peripheral surface of the cylinder 12.

[0038] Figure 4 (a) is a front view of the seal ring 20, Figure 4 (b) is a side view of the seal ring 20, Figure 4 (c) is a cross-sectional view of the seal ring 20 at a line segment B-B shown in (a), Figure 4 (d) is a partial enlarged view of the seal ring 20 shown in (b). The seal ring 20 has a trunk portion 50, a first lip portion 52, and a second lip portion 54. The seal ring 20 has a Y-shaped cross section. Figure 4

[0039] The trunk portion 50, the first lip portion 52, and the second lip portion 54 are each formed in a ring shape. The first lip portion 52 extends toward the axial end portion 50a of the trunk portion 50 and the radial outer side, and extends from the axial end portion 50a of the trunk portion 50 toward the inclined outer side. The second lip portion 54 extends from the axial end portion 50a of the trunk portion 50 toward the radial inner side, and extends from the trunk portion 50 toward the inclined inner side. The first lip portion 52 and the second lip portion 54 are formed so as to approach the axial end portion 50a of the trunk portion 50 in the axial direction, and are formed in two strands. The first lip portion 52 and the second lip portion 54 are thinner than the trunk portion 50 and are flexible. The first lip portion 52 extends toward the radial outer side, and thus can abut against the inner peripheral surface of the cylinder 12.

[0040] The width W of the outline portion of the seal ring 20 is the width W including the radial direction of the first lip portion 52 and the second lip portion 54, and the difference between the outermost diameter and the innermost diameter of the seal ring 20 can be halved to be derived.

[0041] Figure 5 is a cross-sectional view of the damper device 10 at a position passing through the piston 22. The protrusion 32 abuts against the seal ring 20 and presses the seal ring 20 against the inner peripheral surface of the cylinder 12. The interval D between the protrusion 32 and the inner peripheral surface of the cylinder 12 is smaller than the width W of the seal ring 20, and thus the seal ring 20 is pressed against the inner peripheral surface of the cylinder 12 in a crushed manner.

[0042] The outer diameter of the seal ring 20, that is, the outer diameter of the first lip portion 52, is larger than the inner diameter of the cylinder 12. Thus, the state in which the first lip portion 52 abuts against the inner peripheral surface of the cylinder 12 is maintained. The inner diameter of the seal ring 20, that is, the inner diameter of the second lip portion 54, is larger than the outer diameter of the circular-arc portion 33. That is, the second lip portion 54 can or can not abut against the circular-arc portion 33 of the column portion 24. The abutment portion of the seal ring 20 against which the protrusion 32 abuts can be partially expanded in diameter depending on the abutment.​

[0043] Figure 6 (a) and Figure 6 (b) is a diagram used to illustrate the operation of the sealing ring 20, and is a cross-sectional view of the piston 22 portion of the damper device 10. Figure 6 (a) indicates that the sealing ring 20 is in an undeformed state. Figure 6 (b) indicates that the sealing ring 20 is deformed and enters the notch 34.

[0044] The sealing ring 20 abuts against the cylinder 12 and piston 22, dividing the cylinder 12 into a first chamber 60 on the bottom 40 side and a second chamber 62 on the opening 42 side. The body 50 abuts axially against the second limiting portion 28, serving as a seal on the piston 22 side. Furthermore, the first lip 52 abuts radially against the inner circumferential surface of the cylinder 12, serving as a seal on the cylinder 12 side. Thus, the sealing ring 20 completely seals the cylinder 12 and piston 22 without gaps.

[0045] exist Figure 6 In the sealing ring 20 shown in (a), the portion abutting the protrusion 32 is pressed against the inner circumferential surface of the cylinder 12, while the portion not abutting the protrusion 32 is not pressed against the inner circumferential surface of the cylinder 12. The body 50 and the second lip 54 on the inner circumferential side of the sealing ring 20 abut against the protrusion 32. Thus, the first lip 52 can be stably pressed against the cylinder 12.

[0046] At once Figure 6 Regarding the piston 22 shown in (a), the opening action of the opening and closing body pulls the transmission part 14, causing it to advance towards the opening 42 of the cylinder 12. The movement of the piston 22 maintains the sealing ring 20 in its normal state of contact with the second limiting part 28. When the piston 22 advances towards the opening 42, the first chamber 60 becomes under negative pressure due to its increased volume, generating resistance. As a result, the opening and closing body is slowly opened. Furthermore, the negative pressure in the first chamber 60 is eliminated through the throttling orifice formed in the cover 18.

[0047] Here, if the opening and closing body is opened rapidly, the first chamber 60 becomes excessively negatively pressured, increasing the force pulling back the piston 22, causing the opened opening and closing body to retract in the closing direction. If the negative pressure in the first chamber 60 applies a retracting force to the piston 22 and the sealing ring 20, the piston 22 and the sealing ring 20 retract, then as... Figure 6 As shown in (b), the sealing ring 20 is deformed in such a way that it enters the notch 34. The abutting portion of the sealing ring 20 that abuts against the protrusion 32 is pressed more tightly against the inner circumferential surface of the cylinder 12 by the protrusion 32 than the portion other than the abutting portion, and this abutting portion is easily deformed in such a way that it deviates from the piston 22 and enters the notch 34.

[0048] Figure 7is a side view of the seal ring 20 and the piston 22, showing the state in which the seal ring 20 enters the notch portion 34 of the piston 22. That is, Figure 7 The seal ring 20 shown is in the same state as the state in which the seal ring 20 shown in (b) of the same drawing is partially deformed, and can obtain the deformed state in which it is deformed in such a way as to partially enter the notch portion 34 by movement of the piston 22. Figure 6

[0049] The seal ring 20 is deformed in such a way as to enter the notch portion 34, whereby the trunk portion 50 is distanced from the second restriction portion 28, and the seal of the seal ring 20 with the piston 22 is released. Thereby, the air on the second chamber 62 side enters the first chamber 60 from the gap between the second restriction portion 28 and the seal ring 20 through the inside of the seal ring 20 such as the recessed portion 31. Therefore, the negative pressure of the first chamber 60 is released, the pullback of the piston 22 is stopped, and the action of the opening and closing body which was to be closed after having been rapidly opened is released. When the opening and closing body performs the opening action after the negative pressure is released, only the part of the seal ring 20 which entered the notch portion 34 returns to the state of sealing the second restriction portion 28, and therefore the damping force can be exerted immediately after the negative pressure is released.

[0050] In the case where the seal ring 20 is in the deformed state and in the case where the seal ring 20 is in the normal state in which it does not enter the notch portion 34, the seal ring 20 is pressed against the inner peripheral surface of the cylinder tube 12 by the protruding portion 32. That is, the seal ring 20 is pressed against the cylinder tube 12 by the protruding portion 32 in both the normal state and the deformed state. Thereby, the seal ring 20 can maintain the pressing by the protruding portion 32 when it changes from the normal state to the deformed state, and smoothly deforms.

[0051] The trunk portion 50 abuts on the second restriction portion 28 in the axial direction and becomes a seal member on the piston 22 side, and therefore the seal on the piston 22 side is released as soon as the seal ring 20 is distanced slightly from the second restriction portion 28. The seal release can be easily performed even if the deformation amount of the seal ring 20 is small, and therefore the action of pulling back the piston 22 by the negative pressure can be rapidly released.

[0052] The inner diameter R2 of the trunk portion 50 is larger than the outer diameter of the outer peripheral surface 30 of the column portion 24. The inner diameter R2 of the trunk portion 50 is larger than the outer diameter Rl of the circular-arc portion 33 of the column portion 24 and larger than the outer diameter of the column portion 24 including the protruding portion 32. Thereby, compared with the case where the seal ring is in close contact with the outer peripheral surface 30 of the column portion 24 and the inner peripheral surface of the cylinder tube 12, the seal ring 20 can be made to slide easily against the inner peripheral surface of the cylinder tube 12, and the movement of the piston 22 can be made smooth.

[0053] ​In the case where the seal ring 20 is in the deformed state and in the case where the seal ring 20 is in the normal state not entering the notch portion 34, the seal ring 20 is pressed against the inner peripheral surface of the cylinder tube 12 by the protruding portion 32. Thereby, the seal ring 20 is pressed against the cylinder tube 12 by the protruding portion 32 in both the normal state and the deformed state, and the portion being pressed is easily deviated from the piston 22 to become the deformed state.

[0054] The seal ring 20 is partially pressed against the cylinder tube 12 by the protruding portion 32 and is partially deformed. Thereby, the frictional resistance of the seal ring 20 against the cylinder tube 12 can be suppressed. Further, the seal ring 20 returns to the normal state by the restoring force thereof by being partially deformed. Thereby, the free travel distance of the piston 22 until the seal ring 20 is restored can be shortened.

[0055] The present application is not limited to the above-described embodiments, and various design changes and the like can be added to the embodiments based on the knowledge of those skilled in the art, and the embodiments to which such changes are added can also be included in the scope of the present application.

[0056] For example, in the embodiments, the throttle hole is formed in the cap 18, but is not limited to this, and can be formed in the piston 22. Further, in the embodiments, the cross-sectional shape of the cylinder tube 12 and the piston 22 is formed in a circular shape, but is not limited to this, and can be formed in an oblong shape or an elliptical shape.

[0057] Further, in the embodiments, the case where the first restriction portion 26 is located on the opening portion 42 side and the second restriction portion 28 is located on the bottom portion 40 side is shown, but is not limited to this, and the case where the first restriction portion 26 is located on the bottom portion 40 side and the second restriction portion 28 is located on the opening portion 42 side can also be included. Thereby, the timing at which the seal ring 20 performs seal release becomes opposite to the movement of the piston 22. That is, when the first chamber 60 is excessively brought to a positive pressure due to the rapid pressing of the piston 22 and the piston 22 is retracted, the seal ring 20 enters the notch portion 34 to perform seal release.

Claims

1. A damper device, characterized in that, have: A cylinder barrel, having a bottom and an opening; A piston, capable of axial movement within the cylinder; and A sealing ring is located on the outer periphery of the piston and abuts against the inner periphery of the cylinder. The piston has: The column portion is wound around the sealing ring; and The first and second limiting portions are located at both axial ends of the column portion and are formed to extend radially outward from the outer circumferential surface of the column portion, thereby limiting the axial movement of the sealing ring. The column portion has a protrusion that projects radially outward on its outer peripheral surface. The first limiting portion has a notch formed by cutting into the surface opposite to the second limiting portion, and is located at a position axially connected to the protrusion. The sealing ring is configured to seal the second limiting portion and can be deformed by the movement of the piston, allowing it to partially enter the notch. When the sealing ring is in the deformed state and when the sealing ring is in the normal state where it is not inserted into the notch, the sealing ring is pressed against the inner circumferential surface of the cylinder by the protrusion. The protrusion extends from the second limiting portion to the notch of the first limiting portion.

2. The damper device according to claim 1, characterized in that, The sealing ring has: The trunk is formed in a ring shape; and The lips, formed in a ring shape, extend radially outward from the axial end of the torso. The torso abuts against the second limiting part along the axial direction, thus becoming a seal on the piston side. The lip abuts against the inner circumferential surface of the cylinder to become a seal on the cylinder side.

3. The damper device according to claim 2, characterized in that, The protrusion abuts against the torso.

4. The damper device according to claim 2 or 3, characterized in that, The inner diameter of the torso is larger than the outer diameter of the outer circumference of the column.

5. The damper device according to any one of claims 1 to 3, characterized in that, The damper device is connected to the fixed body and the opening / closing body. The damper device further includes a transmission section connected to the piston, which transmits external force to the piston. The cylinder has a first shaft support portion, which is assembled to one of the fixed body and the opening / closing body. The transmission part has a second shaft support part, which is assembled to the other of the fixed body and the opening / closing body, and is parallel to the first shaft support part. The protrusion protrudes axially along the first shaft support and the second shaft support.

6. The damper device according to claim 4, characterized in that, The damper device is connected to the fixed body and the opening / closing body. The damper device further includes a transmission section connected to the piston, which transmits external force to the piston. The cylinder has a first shaft support portion, which is assembled to one of the fixed body and the opening / closing body. The transmission part has a second shaft support part, which is assembled to the other of the fixed body and the opening / closing body, and is parallel to the first shaft support part. The protrusion protrudes axially along the first shaft support and the second shaft support.

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