Damping device

Abstract

The present invention provides a damping device, so that the desired braking force is always obtained from the damping device. The damping device includes a piston body (1) and a cylinder body (2) accommodating the piston body (1), and generates braking force by the movement or relative movement of the piston body (1). A sealing component (9) is combined on the piston body (1) for sealing against the inner wall (2g) of the cylinder body (2). The sealing component (9) has a mounting base (9a) mounted on the piston body (1), a lip (9b) extending from the mounting base (9a) and in sliding contact with the inner wall (2g), and a deflection limiting portion (12) is provided on the piston body (1) for the outer side of the mounting base (9a) side of the sealing component (9).

Description

Technical Field

[0001] The present invention relates to an improvement of a damping device for generating braking force through the action of a piston. Background Art

[0002] As a damping device that generates braking force by the action of a piston, there is a structure shown in Patent Document 1. In the structure of Patent Document 1, a sealing member arranged on the outside of the piston is used to seal the inner wall of the cylinder and the piston. Here, on the sealing member, when a pressure difference is generated between the air chamber formed on one side of the piston and the air chamber formed on the other side by the movement of the piston, a force in the direction of pressing the sealing member against the inner wall of the cylinder acts. However, in the structure shown in Patent Document 1, since the sealing member is simply arranged on the outside of the piston in a manner surrounding the piston, it is difficult to control the deformation of the sealing member caused by the action of such a force. This damping device is typically used to make the braking object move slowly, have a high-level feel, maintain a moderate sense or not sudden, but if the deformation of the sealing member cannot be controlled, the braking force generated by the damping device is unstable, for example, resulting in an emergency stop or multi-stage stop of the braking object or a loss of braking force in a scene where the braking force should act on the braking object.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent document 1: Japanese Patent Application Laid-Open No. 8-133029. Summary of the invention

[0006] The object of the present invention is to provide a damping device, in which a sealing member constituting a piston body is given a structure in which the sealing member always slides in contact with the inner wall of a cylinder body in as similar a form as possible, so that the desired braking force can always be obtained from the damping device.

[0007] To achieve the above object, in the present invention, the damping device includes a piston body and a cylinder body accommodating the piston body, and the braking force is generated by the movement or relative movement of the piston body, wherein:

[0008] The piston body is combined with a sealing member for sealing the inner wall of the cylinder body.

[0009] The sealing member has a lip portion mounted on a mounting base of the piston body, extending from the mounting base and in sliding contact with the inner wall, and

[0010] The piston body is provided with a deflection restricting portion for the outer surface of the sealing member on the side of the mounting base.

[0011] Specifically, the deflection restricting portion is a deflection restricting portion that presses the outer surface of the sealing member on the attachment base side.

[0012] When the space in the cylinder formed on one side of the piston body is expanded by the movement of the piston body, so that the space on the one side becomes negative pressure, a force acts on the mounting base of the sealing member toward the inner wall of the cylinder body. However, since the outer side of the mounting base of the sealing member is pressed by the deflection limiting portion, even if such a force acts, the sealing member does not contact the inner wall of the cylinder body at a portion other than the lip portion. Thus, it is possible to effectively prevent the following situation: when the piston body moves to expand the space on the one side, the braking force generated by the damping device is unstable due to the sealing member contacting the inner wall of the cylinder body at a portion other than the lip portion.

[0013] As one form of the present invention, the piston body is provided with: a flange portion, which is located on one side of the space within the cylinder body divided by the piston body; and a movement limiting portion, which is located on the other side of the space within the cylinder body divided by the piston body, and the mounting base of the sealing component is maintained in a clamped state between the movement limiting portion and the flange portion.

[0014] In one aspect of the present invention, the deflection restricting portion is configured as a wall protruding from the flange portion toward the other space side and extending in a direction perpendicular to the moving direction of the piston body.

[0015] In one aspect of the present invention, the lip portion is formed so that the outer diameter of the sealing member gradually increases as it approaches an extending end of the lip portion, and the connection portion with the mounting base is configured to be easily deformed.

[0016] According to the present invention, by utilizing the deflection restricting portion, the sealing member constituting the piston body can always be in sliding contact with the inner wall of the cylinder body in as similar a form as possible, so that the desired braking force can always be obtained from the damping device. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a perspective view of a damper device (first example) according to one embodiment of the present invention.

[0018] Figure 2 yes Figure 1 Sectional view at the AA line position.

[0019] Figure 3 yes Figure 2 An enlarged cross-sectional view of the main part of the piston shows that the piston body moves in a direction that expands the space on one side.

[0020] Figure 4 yes Figure 2 In the enlarged cross-sectional view of the main part, the piston body moves in the direction of reducing the space on one side.

[0021] Figure 5 This is an exploded perspective view of the first example.

[0022] Figure 6 It is an exploded perspective view of the piston body constituting the first example.

[0023] Figure 7 This is a perspective view of the main parts of the rod constituting the first example.

[0024] Figure 8 It is a perspective view of the main part of the piston body constituting the damper device (second example) according to one embodiment of the present invention.

[0025] Fig. 9 It is a perspective view of the main part of the piston body constituting the damper device (third example) according to one embodiment of the present invention.

[0026] Description of Reference Numerals

[0027] 1 Piston body

[0028] 2 cylinder block

[0029] 2g inner wall

[0030] 9 Sealing member

[0031] 9a Installation base

[0032] 9b Lip

[0033] 12 Deflection limiting section DETAILED DESCRIPTION

[0034] Below, according to Figures 1 to 9 , a typical embodiment of the present invention is described. The damping device of this embodiment generates a braking force by the movement or relative movement of the piston body 1 constituting the damping device, and is typically combined with an object having a movable part (not shown) that becomes a braking object, and is used to apply the braking force to the movement of the braking object, so that the braking object moves slowly, has a high-level feel, maintains a moderate feel, or is not abrupt.

[0035] The damping device comprises: a piston body 1 having a rod body 3; and a cylinder body 2 accommodating the piston body 1. Typically, the damping device is assembled to an object having the braking object by directly or indirectly connecting any one of the rod body 3 and the cylinder body 2 to the braking object side, and directly or indirectly connecting any other of the rod body 3 and the cylinder body 2 to a side that supports the braking object in a movable manner.

[0036] In the example shown in the figure, the cylinder body 2 is in the shape of a cylinder with one end 2a open and the other end 2b closed. Although not shown in the figure, the cylinder body 2 may also be a structure in which one end of the cylinder with both ends open is blocked by another member. The cylinder body 2 is in the shape of a flat cylinder with a significantly small thickness. More specifically, the cylinder body 2 has a width side wall portion 2c and a thickness side wall portion 2d. When the cylinder body 2 is oriented along the central axis x (refer to Figure 5 That is, the moving center axis of the piston body 1. ) In a cross-sectional view in a direction perpendicular to the center axis x, the left and right thickness side wall portions 2d are bent in such a way that the center axis x side is the inner side of the bend, and the cross-sectional inner contour shape of the cylinder body 2 is an oblong. A connecting portion 2e for the above-mentioned connection is formed on the outer side of the closed end 2b of the cylinder body 2.

[0037] In the example shown in the figure, a long hole 3a is formed on the rod body 3 along the moving direction of the piston body 1. Furthermore, in the example shown in the figure, when the piston body 1 and at least the portion of the rod body 3 located on the piston body 1 side are accommodated in the cylinder body 2, the pin 4 is inserted through the through hole 2f formed on a pair of width side wall portions 2c, 2c on the open end 2a side of the cylinder body 2 and the long hole 3a, thereby maintaining the combined state of the cylinder body 2 and the piston body 1 side, and guiding the movement of the piston body 1 side. The sealing member 9 described later constituting the piston body 1 is provided from Figure 6 In the state shown, the piston body 1 undergoes elastic deformation centered on the connection portion 9e described later, and is housed in the cylinder body 2 in this state, so that the extended end of the lip portion 9b described later contacts the inner wall 2g of the cylinder body 2 at any position around the central axis x. The space in the cylinder body 2 is divided into a side space 5 on the closed other end 2b side and a side space 6 on the open one end 2a side by the sealing member 9. The movement of the piston body 1 in the direction of expanding the side space 5 ( Figure 3 ) is allowed by the movement of fluid (gas in the example shown) from the other side space 6 to the one side space 5 through the orifice 14 described later. On the other hand, in the example shown in the figure, when the piston body 1 moves in the direction of reducing the one side space 5 ( Figure 4 ), since one side of the space 5 becomes high pressure, the sealing member 9 is elastically deformed in the direction in which the lip 9b of the sealing member 9 described later moves away from the inner wall 2g of the cylinder body 2, and the fluid moves between the inner wall 2g of the cylinder body 2 and the lip 9b, so that the piston body 1 is allowed to move in this direction.

[0038] The rod body 3 has a rod body 3b and a rod head 3c integrated with the inner end of the rod body 3b located in the cylinder body 2. The rod head 3c has an inner portion 3d and an outer portion 3e whose cross-sectional outer contour shape in the direction perpendicular to the central axis x is an oblong circular shape that imitates the cross-sectional inner contour shape of the cylinder body 2. One end of the rod body 3b is integrated with the center of the outer portion 3e of the rod head 3c. In addition, the connecting portion 3f for connection is formed at the outer end of the rod body 3b located outside the cylinder body 2.

[0039] In the example shown in the figure, a fitted portion 3g is formed at the center of the inner portion 3d side of the rod head 3c, which is fitted with the fitting portion 1a of the piston body 1. In the example shown in the figure, the fitting portion 1a includes a neck 1c and a fitting head 1b, and the fitting head 1b is integrated with the center of the rear end portion 8b described later on the body 8 described later of the piston body 1 through the neck 1c. On the other hand, the fitted portion 3g includes a notch 3h for passing the neck 1c and an embedding cavity 3i for the fitting head 1b formed between the inner portion 3d and the outer portion 3e. In the example shown in the figure, when the sealing member 9 and the movement limiting portion 10, which will become a flat cylindrical shape, are combined with the trunk 8 of the piston body 1 in a manner such that the sealing member 9 and the movement limiting portion 10 surround the trunk 8, the engaging head 1b is accommodated in the embedding cavity 3i by utilizing the cutout 3h of the rod head 3c, thereby integrating the piston body 1 and the rod body 3. At the same time, the sealing member 9 and the movement limiting portion 10 are maintained between the flange portion 7 of the piston body 1 described later and the inner portion 3d of the rod head 3c.

[0040] The piston body 1 includes a flange portion 7 , a body portion 8 , a sealing member 9 , and a movement restricting portion 10 .

[0041] The body 8 is formed along the width direction y of the cylinder 2 (refer to Figure 5 ) direction. The space in the cylinder body 2 is divided into a one-side space 5 and an other-side space 6 by the piston body 1 as described above. The body 8 has a front end 8a facing the one-side space 5 and a rear end 8b facing the other-side space 6.

[0042] The flange 7 is formed in an eave shape at the front end 8a of the body 8. The outer contour of the flange 7 is an oval shape that imitates the inner contour of the cross section of the cylinder 2. A gap 11 (see FIG. 1 ) is formed between the edge 7a of the flange 7 and the inner wall 2g of the cylinder 2 so that a fluid (gas in this embodiment) can pass through at any position around the central axis. Figure 3 as well as Figure 4 ).

[0043] The sealing member 9 has a mounting base 9a that makes the inner surface 9g substantially contact with the piston body 1 and a lip 9b that extends from the mounting base 9a and slides in contact with the inner wall 2g of the cylinder body 2. The sealing member 9 is in the shape of a flat cylinder. The sealing member 9 is typically made of rubber or plastic with rubber-like elasticity. The sealing member 9 is configured so that the cross section in the direction perpendicular to the central axis x is the same shape at any position around the central axis x.

[0044] The sealing member 9 has a portion from its front end portion 9c to the middle position in the front-rear direction (the direction along the central axis x) as the mounting base 9a, and a portion from the middle position to its rear end portion 9d as the lip portion 9b.

[0045] The inner contour shape of the cross section of the attachment base 9a in the direction perpendicular to the central axis x is a shape complementary to the outer contour shape of the cross section of the trunk 8 in the same direction.

[0046] The lip 9b is formed so that the outer diameter of the sealing member 9 gradually increases as it approaches its extension end, so that the connection portion 9e with the mounting base 9a is easily deformed. That is, the lip 9b is in a skirt shape extending from the mounting base 9a toward the other side of the space 6. In the example shown in the figure, the thickness dimension of the connection portion 9e in the direction perpendicular to the central axis x is smaller than that of the other parts of the sealing member 9, so that the connection portion 9e is easily deformed. With such a structure, the lip 9b can always be elastically deformed at a certain position, and the lip 9b can always be in sliding contact with the inner wall 2g of the cylinder body 2 in the same form.

[0047] In the example shown in the figure, a surrounding step surface 9f is formed on the inner side of the sealing member 9, facing the other side space 6. The space between the front end 9c of the sealing member 9 and the surrounding step surface 9f functions as the mounting base 9a, and the space between the surrounding step surface 9f and the rear end 9d of the sealing member 9 functions as the lip 9b.

[0048] The inner surface 9g of the mounting base 9a is a surface substantially parallel to the central axis x. The surrounding step surface 9f is a surface in a direction substantially perpendicular to the central axis x. The extended end of the lip 9b is a thick-walled portion 9h having an outer surface and an inner surface substantially parallel to the central axis x. A connecting portion 9i is formed between the mounting base 9a and the thick-walled portion 9h, and the connecting portion 9i has an outer surface and an inner surface that are inclined in such a manner that the thickness dimension of the lip 9b gradually increases as it approaches the thick-walled portion 9h. The outer surface 9k of the mounting base 9a is formed from the front end portion 9c of the sealing member 9 to the middle position of the mounting base 9a in the front-to-back direction, and the thickness dimension of the mounting base 9a gradually increases as it approaches the middle position (see FIG. 1 ). Figure 6 ).

[0049] The movement restricting portion 10 is located on the other side space 6 side, and holds the attachment base 9 a of the sealing member 9 in a sandwiched state between the flange portion 7 located on the one side space 5 .

[0050] In the example shown in the figure, the movement restricting portion 10 is in a flat cylindrical shape. The inner contour shape of the cross section of the movement restricting portion 10 in the direction perpendicular to the central axis x is complementary to the outer contour shape of the cross section of the trunk portion 8 in the same direction.

[0051] Thus, in the example shown in the figure, the body 8 is penetrated into the sealing member 9, and then the body 8 is penetrated into the movement limiting portion 10, and then, by integrating the piston body 1 and the rod body 3 as described above, the sealing member 9 and the movement limiting portion 10 can be clamped and held from the front and back between the flange portion 7 and the inner portion 3d of the rod head 3c. More specifically, the front end portion 9c of the sealing member 9 is connected to the flange portion 7, the front end portion 10a of the movement limiting portion 10 is connected to the surrounding step surface 9f of the sealing member 9, and the inner portion 3d of the rod head 3c is connected to the rear end portion 10b of the movement limiting portion 10.

[0052] When the piston body 1 moves to reduce the one side space 5 (at Figure 4 In the figure, the movement is in the direction indicated by the arrow), although the sealing member 9 which makes the lip 9b in sliding contact with the inner wall 2g of the cylinder body 2 is subjected to a force opposite to the direction of movement, the sealing member 9 is maintained at the desired position by the movement limiting portion 10, and when the movement of the piston body 1 that reduces the space 5 on one side is performed, the braking force generated by the damping device will not become unstable due to the offset of the sealing member 9, etc.

[0053] In addition, in this embodiment, the piston body 1 has a deflection limiting portion 12 connected to the outer surface 9k of the mounting base 9a side of the sealing member 9. The deflection limiting portion 12 is configured as a wall protruding from the flange portion 7 toward the other side space 6 side and extending in a direction perpendicular to the moving direction of the piston body 1.

[0054] exist Figure 1 to Figure 7 In the first example shown, the deflection restricting portion 12 is formed at a portion other than the center of the edge portion 7a along the long axis of the flange portion 7 having an oblong outer contour shape. That is, the deflection restricting portion 12 is formed at the edge portion 7a ( Figure 6 The flange portion 7 on the upper side of the flange portion 7) and the edge portion 7a (on the other side of the flange portion 7 facing the width side wall portion 2c of the cylinder body 2) of the flange portion 7 Figure 6In the example shown in the figure, the deflection limiting portion 12 is a portion of the flange portion 7 that protrudes toward the other side space 6 from the outer surface 9k of the mounting base 9a covering the sealing member 9, which is the portion of the inclined surface 9j. The outer surface 12a of the deflection limiting portion 12 is substantially parallel to the inner wall 2g of the cylinder 2, and a gap 13 is formed between the two for fluid to pass (see Figure 3 as well as Figure 4 ). The inner contour shape of the deflection restricting portion 12 is a shape that is complementary to the outer contour shape of the mounting base 9a of the sealing member 9. That is, a part of the inner surface 12b of the deflection restricting portion 12 is also configured as an inclined surface.

[0055] In the first example, a first groove 14a is formed at the center of the flange 7 on the surface 7b of the flange 7 facing the other side space 6, which is basically continuous from the edge 7a, and a second groove 14b is formed at the center of the body 8 across the front end 8a and the rear end 8b, and the first groove 14a and the second groove 14b are connected. When the piston body 1 moves to expand the one side space 5 (at Figure 3 The first groove 14a and the second groove 14b become the throttle hole 14 to allow the movement of the piston body 1.

[0056] When the piston body 1 moves to expand the one side space 5 (at Figure 3 Since the side of the one-side space 5 becomes negative pressure, a force acts on the mounting base 9a of the sealing member 9 toward the inner wall 2g of the cylinder body 2 (a force that expands the mounting base 9a), but since the outer side 9k side of the mounting base 9a of the sealing member 9 is pressed by the deflection limiting portion 12, even if such a force acts, the sealing member 9 does not contact the inner wall 2g of the cylinder body 2 at a position other than the lip 9b. Therefore, in this embodiment, the braking force generated by the damping device when the movement of the piston body 1 that expands the one-side space 5 is not destabilized due to the sealing member 9 contacting the inner wall 2g of the cylinder body 2 at a position other than the lip 9b.

[0057] The protruding dimension of the deflection restricting portion 12 from the flange portion 7 is appropriately adjusted as required. That is, the protruding dimension z (see Figure 3 ), there is a case where it can be smaller than the first example, on the other hand, there is a better case where it is larger than the first example, and there is also a better case where the deflection limiting portion 12 protrudes to a position on the side of the connection portion 9e of the lip 9b.

[0058] exist Figure 8In the second example shown, the deflection limiting portion 12 is formed across the entire length of the edge portion 7a along the long axis of the flange portion 7 whose outer contour shape is an oblong. In the second example as well, the deflection limiting portion 12 is formed on the edge portion 7a on one side of the flange portion 7 facing the width side wall portion 2c of the cylinder body 2 and the edge portion 7a on the other side of the flange portion 7 facing the width side wall portion 2c of the cylinder body 2. In the second example, a first groove 14a is formed on the side of the flange portion 7 facing the thickness side wall portion 2d of the cylinder body 2, which is basically continuous from the edge portion 7a, and a second groove 14b is formed on the side of the body 8 facing the thickness side wall portion 2d of the cylinder body 2, which spans between the front end portion 8a and the rear end portion 8b, and the first groove 14a is connected to the second groove 14b. When the movement of the piston body 1 in the one side space 5 is expanded, the first groove 14a and the second groove 14b become a throttle hole 14 to allow the movement of the piston body 1.

[0059] According to the second example, the entire portion of the attachment base 9 a of the sealing member 9 that faces the width side wall portion 2 c of the cylinder 2 can be pressed by the deflection restricting portion 12 .

[0060] exist Fig. 9 In the third example shown, as in the first example, the deflection limiting portion 12 is formed at a portion other than the central position of the edge portion 7a along the long axis of the flange portion 7 whose outer contour shape is an oblong. In addition, in the third example, the deflection limiting portion 12 is connected to the flange portion 7 by using a thin-walled portion 15 that is easily elastically deformed. In the third example, the deflection limiting portion 12 is formed integrally with the flange portion 7 by making one surface that becomes its inner surface 12b the same surface as the surface 7b of the flange portion 7 that faces the other side space 6. Moreover, in the third example, after the body 8 penetrates into the sealing member 9 from the rear end portion 8b side of the body 8 to the position where the front end portion 9c of the sealing member 9 hits the flange portion 7, the deflection limiting portion 12 is bent to a position where the mounting base 9a of the sealing member 9 is sandwiched between the body 8 by using the thin-walled portion 15 as a hinge portion, thereby being able to constitute a piston body 1 substantially the same as the first example.

[0061] In the third example, the movement restricting portion 10 is formed integrally with the trunk portion 8. As shown in the first example, the larger the protruding dimension of the deflection restricting portion 12 is, the larger the gap 16 (see FIG. 1 ) between the deflection restricting portion 12 and the movement restricting portion 10 is. Figure 3 ), but if it is constructed as in the third example, even if the body 8 and the movement limiting portion 10 are integrated, the mounting base 9a of the sealing member 9 can be accommodated inside the flexure limiting portion 12 without hindrance.

[0062] In addition, it is needless to say that the present invention is not limited to the above-described embodiment, but includes all embodiments that can achieve the object of the present invention.

Claims

1. A damping device, comprising a piston body and a cylinder body accommodating the piston body, wherein a braking force is generated by movement or relative movement of the piston body, wherein: The piston body is provided with: a flange portion located on one side of a space in the cylinder body divided by the piston body; a movement limiting portion located on the other side of a space in the cylinder body divided by the piston body; and The piston body is combined with a sealing member for sealing the inner wall of the cylinder body. The sealing member comprises a mounting base mounted on the piston body, and a lip extending from the mounting base and in sliding contact with the inner wall, wherein the lip is in a skirt shape extending from an end of the mounting base on the other side space side toward the other side space side. The mounting base of the sealing member is held in a sandwiched state between the movement restricting portion and the flange portion, The piston body is provided with a deflection restricting portion that protrudes from the flange portion toward the other space side and contacts the outer surface of the sealing member on the mounting base side.

2. The damping device according to claim 1, wherein: The deflection restricting portion protruding from the flange portion toward the other space side is configured in a wall shape that is long in a direction perpendicular to the moving direction of the piston body.

3. The damping device according to claim 1 or 2, wherein: The lip portion is formed so that the outer diameter of the sealing member gradually increases as it approaches the extending end of the lip portion, and is configured so that the connection portion with the mounting base can be easily deformed.

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