JP2015230017A - Air damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air damper capable of achieving miniaturization while keeping desired braking force.SOLUTION: An air damper 10 includes: a cylinder 20 having a cylindrical wall 23; a piston 30 slidably inserted into the cylinder; a rod 50; a flow passage communicating an inner space surrounded by a cylinder close part and a piston 30 with an outer side; and braking force imparting means for narrowing the flow passage so as to impart braking force to the piston 30 when the piston 30 is slid to a direction separating from or approaching the close part of the cylinder 20, and extending the flow passage so as to release the braking force of the piston 30 when the piston 30 is moved to a direction opposite to the direction. A cross section of the wall 23 of the cylinder 20 orthogonal to an axial direction is formed in a cross sectional shape having a long axis and a short axis.

Description

  The present invention relates to an air damper used for braking such as opening / closing operation of a glove box of an automobile.

  For example, an air damper is used in a glove box of an automobile in order to prevent it from opening suddenly and open it gently.

  As a conventional air damper of this type, Patent Document 1 below discloses a cylinder having one end opened and the other end closed, and a reciprocatingly inserted cylinder. The cylinder is divided into axial front and rear chambers. The piston is composed of a split piston and an O-ring fitted on the outer periphery of the piston. The piston has a hollow cylindrical shape with an open front surface and a closed rear surface. Cylinder-type air comprising an orifice that exchanges air between the two chambers with each other in the axial direction, a ring groove provided on the outer periphery, and a ventilation groove closed by an O-ring moving in the ring groove. A damper is described. The cylinder in the air damper has a cylindrical shape with a circular cross section corresponding to the cylindrical piston.

  In this air damper, when the piston moves away from the back of the cylinder, air flows into the front and rear chambers through the orifice, so that braking force is applied, and on the other hand, the piston moves toward the back of the cylinder. Then, by the movement of the O-ring, air flows at a stroke through the ventilation groove and is pushed in smoothly.

JP-A-2-129424

  In the air damper disclosed in Patent Literature 1, the volume of the cylinder is determined by the inner diameter of the cylindrical cylinder, and this is one of the factors that determine the braking force of the air damper.

  That is, in order to obtain a constant braking force, the inner diameter of the cylinder must be secured to some extent, but when an air damper having such a cylindrical cylinder is arranged on one side in the width direction of a glove box, for example, However, the size in the width direction of the glove box or the like is increased, and it is difficult to achieve a compact size.

  Accordingly, an object of the present invention is to provide an air damper that can be made compact while maintaining a desired braking force.

  In order to achieve the above object, an air damper according to the present invention has a cylindrical wall portion, a cylinder having a closed portion at one end and an opening at the other end, and a slidable insert into the cylinder. A piston connected to the piston and extending from an opening at the other end of the cylinder, and a flow passage that communicates the closed portion of the cylinder and the internal space surrounded by the piston to the outside. When the piston slides away from or close to the closed part of the silicinda, the flow passage is narrowed to apply a braking force to the piston, and the piston moves in the opposite direction. And a braking force applying means for releasing the braking force of the piston by expanding the flow passage, and the cross section perpendicular to the axial direction of the wall portion of the cylinder has a cross sectional shape having a major axis and a minor axis. There is And wherein the door.

  In the air damper of the present invention, the piston has a mounting surface on which a seal ring that is in close contact with the inner periphery of the wall of the cylinder is mounted, and a part of the mounting surface is in the long axis direction of the cross section of the wall of the cylinder A straight wall surface extending to the seal wall is formed with a seal surface in close contact with the seal ring, and a groove portion forming a flow channel communicating with the inside of the cylinder on the inner periphery of the seal ring. At least a portion of the ring passing through the straight wall surface closes the flow path passing through the groove portion in close contact with the seal surface when the piston moves in a direction to receive the braking force, and the piston releases the braking force. When moving in the direction to be performed, it is preferable to be configured to open the flow path passing through the groove portion away from the sealing surface.

  In the air damper of the present invention, it is preferable that the seal ring has a circular shape in the absence of external force before being mounted on the piston.

  In the air damper of the present invention, the seal ring is restricted between movement of the piston in the axial direction at both ends of the linear wall surface of the piston, and is positioned between both ends of the linear wall surface, It is preferable that a portion passing through the linear wall surface is configured to move in the axial direction of the piston to open and close a flow path passing through the groove.

  In the air damper of the present invention, the piston conforms to the cross-sectional shape of the wall portion of the cylinder and has a cross-sectional shape having a major axis and a minor axis, and the front end surface of the piston on the closing portion side of the cylinder A convex portion is formed in a portion near at least one end in the major axis direction toward the piston insertion direction into the cylinder, and the convex portion is formed in the piston insertion direction into the cylinder. A first taper surface formed on both side surfaces in the short axis direction so as to become narrower and / or a first taper surface formed so as to gradually decrease toward the other end side in the long axis direction of the piston. It is preferable that two taper surfaces are provided.

  In the air damper of the present invention, it is preferable that the first tapered surface is a surface on which the second tapered surface is formed and reaches the side surface in the minor axis direction.

  In the air damper according to the aspect of the invention, it is preferable that the convex portions are respectively provided at both end portions of the front end surface of the piston in the major axis direction.

  In the air damper of the present invention, a cap is attached to the other end opening of the cylinder opposite to the closed portion, and the cap has an insertion hole through which the rod is movably inserted. And has a plug portion inserted into the opening of the cylinder, the plug portion being adapted to the cross-sectional shape of the wall portion of the cylinder and having a cross-sectional shape having a major axis and a minor axis. In addition, a convex portion is formed at the tip end surface in the insertion direction into the cylinder and at least near one end portion in the major axis direction toward the insertion direction into the cylinder. The first taper surface formed on both side surfaces of the insertion portion in the short axis direction so as to become narrower toward the insertion direction into the cylinder, and / or the long axis direction of the insertion portion. A second tapered surface formed so as to gradually become lower toward the other end side is provided. It is preferred that the.

  According to the air damper of the present invention, the cross section of the wall portion of the cylinder perpendicular to the axial direction has a cross-sectional shape having a major axis and a minor axis, so that the volume of the internal space surrounded by the closed portion of the cylinder and the piston It is possible to reduce the size of the cylinder in the width direction while securing the above. For example, when installing the air damper for opening / closing braking of the lid with respect to the glove box, the air damper can be attached even if there is no room for the attachment space, and convenience can be improved.

It is a disassembled perspective view which shows one Embodiment of the air damper of this invention. FIG. 3 is a perspective view of the air damper in a state where a cylinder is seen through. The piston and the rod which comprise the air damper are shown, (a) is the side view, (b) is the side view of the state which mounted | wore with the seal ring, (c) is sectional drawing. It is explanatory drawing which shows the internal structure of the air damper. (A) is explanatory drawing of the state which attached the seal ring to the piston, (b) is sectional drawing seen from the direction orthogonal to the axial direction of an air damper. The operation state at the time of applying the braking force of the air damper is shown, (a) is an explanatory view in a state where the piston is pushed in until it abuts against the cylinder blockage portion, and (b) is a movement of the piston a predetermined distance from the cylinder blockage portion. (C) is explanatory drawing in the state by which the piston and the rod were pulled out from the cylinder to the maximum. The operation state when the braking force of the air damper is released is shown, (a) is an explanatory diagram in a state where the piston and the rod are pulled out from the cylinder to the maximum, and (b) is a predetermined distance toward the cylinder closing portion. Explanatory drawing of the pushed state, (c) is explanatory drawing in the state pushed in until a piston contact | abuts a Linder obstruction | occlusion part. It is a cross-sectional perspective view in the vicinity of the opening of the air damper. FIG. 3 is an exploded perspective view of the air damper in a state where a wall of a cylinder is narrowed. FIG. 10 is a perspective view showing a state in which a piston is inserted into an opening of a cylinder in the air damper shown in FIG. 9. It is an expansion perspective view of FIG. FIG. 10 is a cross-sectional perspective view showing a state where the piston is inserted into the opening of the cylinder in the air damper shown in FIG. 9. It is a disassembled perspective view which shows other embodiment of the air damper of this invention. The piston and the rod which comprise the air damper are shown, (a) is the side view, (b) is the side view of the state which mounted | wore with the seal ring. The operation state when the braking force of the air damper is released is shown, (a) is an explanatory diagram in a state where the piston and the rod are pulled out from the cylinder to the maximum, and (b) is a predetermined distance toward the cylinder closing portion. Explanatory drawing of the pushed state, (c) is explanatory drawing in the state pushed in until a piston contact | abuts a Linder obstruction | occlusion part. (A) is explanatory drawing of the air damper which has a cylinder and piston of a circular section, (b) is an enlarged view of (a).

  Hereinafter, an embodiment of an air damper of the present invention will be described with reference to the drawings.

  The air damper 10 is disposed between a pair of opening and closing members that relatively open and close. For example, a glove box that can be opened and closed in an opening of a housing portion provided in an instrument panel of an automobile. It can be used for braking, such as a lid.

  As shown in FIG. 1, the air damper 10 includes a cylinder 20 having one end closed and the other end opened, a piston 30 slidably inserted into the cylinder 20, and a rod 50 connected to the piston 30. And a seal ring 80 attached to the outer periphery of the piston 30 and a cap 60 attached to the other end opening of the cylinder 20. The seal ring 80 has a circular shape in a state where there is no external force before being attached to the piston 30 (FIG. 1 shows a shape inserted into the cylinder for convenience).

  As shown in FIGS. 1 and 4, the cylinder 20 has a wall portion 23 extending in a cylindrical shape with a predetermined length, one end of which is closed by a closing portion 21, and an opening portion 22 is provided at the other end. It has been. Further, as shown in FIG. 5 (b), the cross section perpendicular to the axial direction of the wall portion 23 of the cylinder 20 has a long axis A and a short axis B, and has an annular cross-sectional shape extending long in one direction. ing. In this embodiment, the wall portion 23 includes linear wall portions 25 and 25 that extend linearly along the major axis A direction and are arranged to be parallel to each other. Both end portions of 25 and 25 are connected by arc-shaped wall portions 26 and 26 bent in an arc shape. Further, on the opening portion 22 side of the cylinder 20 and in the approximate center of the linear wall portions 25, 25, a long hole-like engagement hole 22a is formed (see FIG. 1).

  A mounting piece 27 having a mounting hole 27a extends from the outer surface of the closing portion 21 of the cylinder 20, and the cylinder 20 is attached to an opening / closing mechanism such as a glove box or a lid via the mounting piece 27. It is like that.

  Further, in this embodiment, the closed portion 21 is provided at one end of the cylinder 20, but with one end of the cylinder 20 as an opening, a cap that is separate from or integrated with the cylinder 20 is attached to the one end opening. One end opening of the cylinder 20 may be closed. In this case, the cap member forms a “blocking portion”.

  The cylinder 20 may have a cross-sectional shape having a major axis A and a minor axis B, such as a rectangular shape or an elliptical shape, and is not particularly limited.

  As shown in FIGS. 2, 3 and 5, the piston 30 has a cylindrical shape with one end closed by a bottom and the other end opened, and a seal ring 80 is mounted on the outer periphery thereof.

  The piston 30 of this embodiment has a cross-sectional shape having a major axis A and a minor axis B in conformity with the shape of the cylinder 20 (see FIG. 5A). The piston 30 has a mounting surface on which a seal ring 80 that is in close contact with the inner periphery of the wall portion 23 of the cylinder 20 is mounted. A part of the mounting surface is a long axis of a cross section of the wall portion of the cylinder 20. A straight wall surface 33 extending in the A direction is formed. In this embodiment, both side surfaces along the long axis A of the piston 30 form linear wall surfaces 33 and 33 extending linearly in parallel with each other so as to fit the linear wall portion 25 of the cylinder 20 ( (See FIG. 3A and FIG. 5B).

  In addition, a pore-shaped orifice 32 is formed through one end of the bottom of the piston 30 in the major axis A direction (see FIG. 3C).

  By inserting the piston 30 into the cylinder 20, an internal space S <b> 1 (see FIGS. 6 and 7) surrounded by the wall portion 23, the closing portion 21, and the piston 30 is formed in the cylinder 20. However, the orifice 32 forms one of the “flow passages” in the present invention that communicates the internal space S1 of the cylinder 20 with the outside (here, the external communication space S2 between the piston 30 and the cap 60). . When the closed portion of the cylinder 20 is a cap member, an orifice can be provided in the cap member. In this case, the “outside” means the outside of the cylinder 20.

  In this embodiment, when the piston 30 slides in the braking direction (the direction away from the closed portion 21 of the cylinder 20), the internal space S1 is depressurized, and the piston 30 moves in the direction opposite to the braking direction (the closed portion 21 of the cylinder 20). The braking force is applied to the piston 30 by being pulled in the direction of approaching. At that time, the air flows from the external communication space S2 to the internal space S1 through the orifice 32 (see the arrow in FIG. 6B) so that the braking force applied to the piston 30 is adjusted. It has become.

  Further, flange holding walls 35, 35 projecting from the outer periphery of both ends of the major axis A direction on the proximal end side in the axial direction of the piston 30. Further, a flange-shaped ring holding wall 36 projects from the position near the tip of the piston 30 in the axial direction and away from the ring holding wall 35 over the entire circumference of the piston. In this embodiment, the distance between the ring holding walls 35, 36 is a dimension that is substantially adapted to the thickness of the seal ring 80.

  As shown in FIG. 3A, the inner surface of the ring holding wall 36 on the tip side of the piston 30 is a seal surface 39 (see FIG. 3) that seals the gap between the piston 30 and the cylinder 20 when the seal ring 80 is in close contact. 3 (a)). Further, in the portion located on the linear wall surface 33 between the ring holding walls 36 and 35, when the seal ring 80 is separated from the seal surface 39, it passes through the inner periphery of the seal ring 80, and the piston 30 and the cylinder 20. A groove 41 is formed to communicate the internal space S1 surrounded by the outside.

  In this embodiment, three groove portions 41 are provided in parallel along the longitudinal direction of the rod 50 via ribs. The groove 41 forms one of the “flow passages” in the present invention that communicates the internal space S1 of the cylinder 20 with the outside (external communication space S2).

  In the portions of the ring holding walls 35, 35 passing through the linear wall surface 33, the ribs disappear and a gap 35 a is formed. Since the ring holding walls 35 and 36 are formed at an interval substantially matching the outer diameter of the seal ring 80, the seal ring 80 is disposed between the ring holding walls 35 and 36. Although the movement of the piston 30 in the axial direction is restricted at both ends of the linear wall surface 33 of the piston 30 (see FIGS. 6 and 7), the portion of the gap 35a between the ring holding walls 35, 35 (the present invention). , The seal ring 80 is movable in the axial direction of the piston 30 so as to protrude from the gap 35a at “a portion located between both ends of the linear wall surface and passing through the linear wall surface”. And is configured to open and close a flow path passing through the groove 41 (see FIGS. 7A and 7B).

  In the state where the seal ring 80 is mounted on the outer periphery of the piston as described above, the circular seal ring 80 is stretched so as to form a substantially elliptical shape and is in close contact with the outer periphery of the piston 30. In the portion passing through the straight wall 33, the elastic force spreading toward the outer diameter side is maintained (see FIG. 5A), and when the piston 30 is inserted into the cylinder 20, the seal ring is formed on the inner periphery of the wall of the cylinder 20. 80 closely contacts, so that the gap between the inner circumference of the wall portion of the cylinder 20 and the outer circumference of the piston 30 is well sealed (see FIG. 5B).

  6 (a) and 6 (b), in the air damper 10, when the piston 30 slides in a direction away from the closing portion 21 of the cylinder 20, the seal ring 80 is formed on the seal surface 39 side of the piston 30. Since the groove 41 is closed by the seal ring 80, only the orifice 32 becomes a flow passage. As a result, the internal space S1 of the cylinder 20 is decompressed, and the braking force is applied to the piston 30 by the air resistance (see FIGS. 6B and 6C).

  On the other hand, as shown in FIGS. 7A and 7B, when the piston 30 slides in the direction approaching the closing portion 21 of the cylinder 20, the gap 35 a that is not held by the ring holding wall 35 of the seal ring 80. It curves and deforms so as to protrude (see FIG. 7B), moves from the seal surface 39 of the linear wall surface 33 to the groove portion 41, and communicates with the inner periphery of the seal ring 80 into the cylinder via the groove portion 41. A flow path is formed (see FIG. 8), thereby widening the flow path. As a result, the air in the internal space S1 of the cylinder 20 is exhausted to the external communication space S2 through the flow passage, so that the braking force applied to the piston 30 is released.

  Thus, in this embodiment, the piston 30, the orifice 32 and groove 41 provided in the piston 30, and the seal ring 80 constitute the “braking force applying means” in the present invention.

  Contrary to this embodiment, when the piston slides in the direction approaching the closed portion of the cylinder, the flow passage is narrowed to apply a braking force, and when the piston slides in the direction away from the flow passage, The braking force may be released by widening.

  In the air damper 10, as shown in FIG. 1, the front end surface of the piston 30 on the closed portion 21 side of the cylinder 20 (here, the front end surface of the ring holding wall 36), Convex portions 43 and 43 each having a substantially U-shaped frame project from both ends. Moreover, the 1st taper surface 45 is each formed in the both-sides surface of the short axis B direction of the piston 30 so that it may become narrow gradually toward the piston insertion direction to the cylinder 20 at the outer peripheral surface of each convex part 43. ing.

  Furthermore, a second taper surface 47 that gradually decreases toward the other end side in the long axis A direction is formed on the surface on the other end side in the long axis A direction of the convex portion 43 on one end side in the long axis A direction of the piston 30. A second tapered surface 47 that gradually decreases toward one end side in the long axis A direction is formed on the surface of one end side in the long axis A direction of the convex portion 43 on the other end side in the long axis A direction of the piston 30. Yes. In this embodiment, the 2nd taper surface 47 is each formed in the inner surface which both convex parts 43 and 43 oppose.

  The first taper surface 45 is a surface of each convex portion 43 on which the second taper surface 47 is formed and extends to the side surface in the minor axis B direction.

  The protrusions 43 are not provided at both ends of the piston 30 in the long axis A direction as described above, but are formed on the tip surface of the piston 30 and at least near one end portion in the long axis A direction of the piston 30. There is no particular limitation. Further, only one of the first tapered surface 45 and the second tapered surface 47 may be provided on the convex portion 43.

  As shown in FIGS. 1 and 3, a rod 50 extending from the opening 22 of the cylinder 20 is connected to the proximal end side of the piston 30. The rod 50 has a long cross-sectional shape in one direction corresponding to the cross-sectional shapes of the cylinder 20 and the piston 30, and a mounting portion 51 is provided at the tip of the rod 50. It can be attached to the opening and closing mechanism.

  Moreover, the recessed part 53 of predetermined depth is formed in the both sides | surfaces of the rod 50 along an axial direction, and when the piston 30 and the rod 50 move in the cylinder 20, the air in the cylinder 20 can distribute | circulate. It has become. Further, a plurality of ribs 55 project from the proximal end side of the rod 50 at a predetermined interval. In this embodiment, the two ribs 55 are protruded, but may be one, or may be three or more. When the cap 60 is attached to the opening 22 of the cylinder 20, the rib 55 is disposed on the back side of the locking claw 67 of the cap 60, as shown in FIG. It is intended to regulate the bending to.

  As shown in FIGS. 1, 2, and 4, the cap 60 attached to the opening 22 on the other axial end side of the cylinder 20 covers the long axis A and the short axis so as to cover the opening 22 of the cylinder 20. It has a long plate shape having B, and has a base portion 61 whose both ends are rounded in an arc shape. The base 61 is formed with a rectangular long hole-like insertion hole 63 through which the rod 50 is movably inserted (see FIG. 6). Furthermore, it is the back side of the base 61, and from a slightly inner side of the peripheral edge thereof, it is inserted into the opening 22 of the cylinder 20 (see FIG. 4) and has a cross-sectional shape having a major axis A and a minor axis B (illustrated). (Omitted) An elongated cylindrical portion 65 is extended. Note that the distal end side of the insertion portion 65 has a shape with a slightly reduced diameter via a stepped portion.

  In addition, a slit 66 having a substantially U-shape is formed at substantially the center of both side surfaces of the insertion portion 65 in the short axis B direction, and a locking claw 67 that can be bent through the slit 66 is provided. The engaging claw 67 engages with the engaging hole 22a of the opening 22 of the cylinder 20 so that the cap 60 is attached to the opening 22 of the cylinder 20.

  The slit 66 in this embodiment includes a pair of horizontal grooves 66a extending along the extending direction of the insertion portion 65, and a vertical groove 66b connecting the base ends of the pair of horizontal grooves 66a, 66a. Thus, one end of the locking claw 67 is connected to the distal end side (insertion direction side to the cylinder) of the insertion portion 65 and the other end forms a free end separated from the insertion portion 65.

  From the front end surface of the insertion portion 65 in the insertion direction to the cylinder 20, the convex portion having the same structure as the convex portion 43 of the piston 30 having the first tapered surface 45 and the second tapered surface 47. 73 is protrudingly provided.

  That is, as shown in FIG. 2, convex portions 73, 73 each having a substantially U-shaped frame project from both ends of the insertion portion 65 in the major axis A direction, and the outer periphery of each convex portion 73. First tapered surfaces 75 are formed on both side surfaces of the insertion portion 65 in the minor axis B direction so that the width gradually decreases in the direction of insertion into the cylinder 20. Furthermore, a second tapered surface 77 that gradually decreases toward the other end side in the long axis A direction is formed on the other end side in the long axis A direction of the convex portion 73 on one end side in the long axis A direction of the insertion portion 65. The second tapered surface 77 gradually lowers toward the one end side in the long axis A direction on the surface on the one end side in the long axis A direction of the convex portion 73 on the other end side in the long axis A direction of the insertion portion 65. Is formed. The first taper surface 75 is a surface of each convex portion 73 on which the second taper surface 77 is formed and extends to the side surface in the minor axis B direction.

  In addition, the said convex part 73 should just be formed in the front end surface of the insertion part 65, Comprising: At least the one end part vicinity of the major axis A direction of the insertion part 65, It does not specifically limit.

  Next, the function and effect of the air damper 10 having the above configuration will be described.

  In this air damper 10, the wall portion 23 of the cylinder 20 has a cross-sectional shape having a major axis A and a minor axis B. Therefore, as shown in FIG. Further, opposing wall portions arranged along the major axis A direction of the cylinder 20, that is, central portions of the linear wall portions 25, 25 are curved inwardly of the cylinder, and the opening portion 22 of the cylinder 20 is narrow. As a result, the piston 30 could not be inserted into the cylinder 20 and the cap 60 could not be attached to the opening 22 of the cylinder 20. Even in such a case, in the air damper 10, the piston 30 can be inserted into the cylinder 20, and the cap 60 can be attached to the opening 22 of the cylinder 20. This will be described with reference to FIGS.

  That is, the piston 30 equipped with the seal ring 80 is inserted into the opening 22 of the cylinder 20 from the tip side.

  At this time, since the protrusions 43 and 43 having the first taper surface 45 and the second taper surface 47 project from the tip surface of the piston 30, the opening 22 of the cylinder 20 is narrowed as described above. However, each convex portion 43 is inserted into the opening portion 22 first, and the first tapered surface 45 is guided in contact with the inner periphery of the end portion of the opening portion 22 in the major axis A direction. The convex portions 43 and 43 are pushed in while the tapered surface 47 is guided by being in contact with the inner periphery of the narrow portion H of the opening 22 (see FIG. 10). Further, when the piston 30 is further pushed in, the narrow portion H of the opening 22 is pushed (see FIGS. 11 and 12), so that the piston 30 can be inserted into the cylinder 20.

  Thus, according to the air damper 10, when the piston 30 is to be inserted in a state where the opposing wall portions of the cylinder 20 are curved inward and the interval between the openings 22 is narrowed, 30 is inserted into the opening 22 first, and the piston 30 is gradually pushed in by using the first taper surface 45 and / or the second taper surface 47 as a guide. Since the piston 30 can be inserted while expanding the narrow portion H of the cylinder 22, the piston 30 can be smoothly moved into the cylinder 20 even when the opening portion 22 of the cylinder 20 has the narrow portion H. And can be inserted securely.

  Further, in this embodiment, the first tapered surface 45 is a surface on which the second tapered surface 47 is formed, and is formed up to the side surface in the minor axis B direction of the piston 30 (see FIG. 1). ) When the convex portion 43 of the piston 30 is inserted into the opening portion 22 of the cylinder 20, the narrow portion H of the wall portion 23 of the cylinder 20 can be expanded through the first tapered surface 45 and the second tapered surface 47. The piston 30 can be inserted more smoothly.

  Furthermore, in this embodiment, since the convex part 43 is provided in the both ends of the major axis A direction of the front end surface of the piston 30, the convex part is provided at both ends of the opening 22 of the cylinder 20 in the major axis A direction. 43 and 43 can be inserted at the same time, the narrow portion H of the opening 22 can be pushed more efficiently, and the workability of inserting the piston 30 into the cylinder 20 can be further improved.

  As described above, after the piston 30 is inserted into the cylinder 20, the tip of the rod 50 connected to the piston 30 is inserted into the insertion hole 63 of the cap 60, and the cap is directed toward the opening 22 of the cylinder 20. Push 60 in.

  Then, similarly to the piston 30, the convex portions 73, 73 protruding from the distal end surface of the insertion portion 65 of the cap 60 are inserted into the opening portion 22 first, and the first taper surface 45 becomes the opening portion 22. The second taper surface 47 is guided in contact with the inner periphery of the narrow portion H of the opening 22 while being guided by contact with the inner periphery of the end in the major axis A direction. It is pushed in. At the same time, the locking claws 67 and 67 of the cap 60 are pressed against the inner periphery of the cylinder 20 and are pushed in while being bent. When the piston 30 is further pushed in, the narrow portion H of the opening 22 is pushed and widened, the insertion portion 65 is inserted into the cylinder 20, and the locking claw 67 engages with the opening 22 of the cylinder 20. When reaching the hole 22 a, the locking claw 67 is elastically restored and engaged with the engagement hole 22 a, and the cap 60 is attached to the opening 22.

  Thus, according to this embodiment, since the cap 60 is also provided with the convex portion 73 having the first tapered surface 75 and the second tapered surface 77 similar to the piston 30, the insertion portion of the cap 60 The 65 convex portion 73 is inserted into the opening portion 22 of the cylinder 20, and the narrow portion of the opening portion 22 of the cylinder 20 is guided by the first tapered surface 75 and / or the second tapered surface 77 provided on the convex portion 73. Since the insertion portion 65 can be inserted while expanding H, the cap 60 can be smoothly and reliably attached to the opening 22 of the cylinder 20.

  As described above, the air damper 10 in which the piston 30 and the rod 50 are inserted into the cylinder 20 and the cap 60 is attached to the opening 22 thereof is, for example, the mounting piece 27 of the cylinder 20 and the mounting portion 51 of the rod 50. It can attach to the side part of the glove box which is not illustrated via.

  At this time, according to the air damper 10, as shown in FIG. 5B, the cross section perpendicular to the axial direction of the wall portion 23 of the cylinder 20 has a cross-sectional shape having a major axis A and a minor axis B. Therefore, while ensuring the volume of the internal space S1 of the cylinder 20, the size in the width direction of the cylinder 20 can be reduced. As described above, when installing the air damper for opening / closing braking of the lid with respect to the glove box, Even if there is no room in the installation space, it can be installed and the convenience can be improved.

  Then, the lid is closed with respect to a glove box (not shown), that is, as shown in FIG. 6A, the piston 30 is pressed against the closing portion 21 of the cylinder 20, and the rod 50 is inserted into the insertion hole 63 of the cap 60. When the lid is opened in the state of being pulled in, as shown in FIG. 6B, the rod 50 is pulled out from the insertion hole 63, and the piston 30 slides in a direction away from the closing portion 21 of the cylinder 20. Then, the seal ring 80 moves to the seal surface 39 side of the piston 30, the gap between the seal ring 80 and the piston 30 is closed and the flow path is narrowed, so that the internal space S <b> 1 of the cylinder 20 is depressurized and the orifice 32. The air moves from the external communication space S2 to the internal space S1 (see the arrow in FIG. 6B), and the braking force is applied to the piston 30 by the air resistance, so that the lid can be opened gently (FIG. 6 ( c)).

  When the piston 30 is farthest from the closing portion 21 of the cylinder 20, the ring holding walls 35, 35 of the piston 30 abut against the protrusions 75, 75 at the tip of the insertion portion 65 of the cap 60. Further, the withdrawal of the rod 50 is restricted.

  On the other hand, when the lid is closed with respect to a glove box (not shown), that is, as shown in FIGS. 7A and 7B, when the piston 30 slides in the direction close to the closing portion 21 of the cylinder 20, The intermediate portion that is not held by the ring holding wall 35 of 80 is curved and deformed so as to enter the gap 35a between the ring holding walls 35 and 35 (see FIG. 7B). Then, it moves from the sealing surface 39 of the linear wall surface 33 to the groove portion 41, and a flow path communicating with the inside of the cylinder via the groove portion 41 is formed on the inner periphery of the seal ring 80 (see FIG. 8), thereby circulating. Since the path widens, the air in the internal space S1 of the cylinder 20 is exhausted to the external communication space S2 through this flow path, the braking force applied to the piston 30 is released, and the lid can be quickly closed. (See FIG. 7C).

  As described above, according to this embodiment, when the piston 30 moves in the direction of receiving the braking force, the seal ring 80 moves to the seal surface 39 of the linear wall surface 33, so that the gap between the seal ring 80 and the piston 30 is Is closed to narrow the flow path, and a braking force can be applied to the piston 30. Further, when the piston 30 moves in the direction in which the braking force is released, the seal ring 80 moves toward the groove 41, and a flow path communicating with the inside of the cylinder via the groove 41 is provided on the inner periphery of the seal ring 80. Since the flow passage is widened, the braking force applied to the piston can be released.

  Further, in this embodiment, the seal ring 80 is restricted from moving in the axial direction of the piston 30 at both ends of the linear wall surface 33 of the piston 30 and is positioned between both ends of the linear wall surface 33. Thus, the portion passing through the linear wall surface 33 is configured to move in the axial direction of the piston 30 to open and close the flow path passing through the groove portion 41. Therefore, when the piston 30 is moved in the direction in which the braking force is released, the seal ring 80 moves on the linear wall surface 33, and the flow path is widened through the groove portion 41 (see FIGS. 7B and 8). ) When the braking force is released and the piston 30 is stationary, the intermediate portion of the seal ring that has moved to the linear wall surface 33 due to the tension of the seal ring 80 returns to the seal surface 39 (see FIG. 7C). When the piston 30 is moved again in the direction in which the braking force is applied, the braking force can be immediately applied.

  At this time, in this embodiment, since the groove part 41 which forms the flow path connected to the inside of the cylinder in the inner periphery of the seal ring 80 is provided in the linear wall surface 33 of the piston 30, the following operational effects Is brought about. That is, as shown in FIG. 16, when the cylinder 20A or the piston 30A has a circular shape and the groove 41A is formed on the peripheral surface of the piston 30A, when the seal ring 80 moves due to the sliding of the piston 30, A part of the inner periphery of the seal ring 80 slightly falls into the groove 41A (see the broken line in FIG. 16B), and the seal ring 80 is caught at this part, and the seal ring 80 may not move smoothly. It was. On the other hand, according to the air damper 10 of this embodiment, since the groove portion 41 is provided on the linear wall surface 33, when the seal ring 80 moves as the piston 30 slides, the groove portion 41 is sealed. The ring 80 can be made difficult to be caught, whereby the seal ring 80 can be moved smoothly, and the response performance of the piston 30 can be improved (see FIG. 5B).

  Further, in this embodiment, the seal ring 80 has a circular shape in the absence of external force before being attached to the piston 30. Therefore, when the seal ring 80 is attached to the piston 30, Since a force to spread outward acts (see FIG. 5A), the pressure contact force of the seal ring 80 with respect to the inner periphery of the cylinder wall can be increased to improve the sealing performance.

  FIGS. 13 to 15 show other embodiments of the air damper of the present invention. Note that substantially the same parts as those of the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted.

  The air damper 10a of this embodiment is different in piston shape from that of the above embodiment.

  That is, as shown in FIGS. 13 and 14, the piston 30a of the air damper 10a has a gap between the ring holding wall 35 provided on the axial base end side of the piston 30a and the ring holding wall 36 provided on the distal end side. The seal ring 80 is formed to be larger than the thickness thereof. As a result, the seal ring 80 is mounted on the outer periphery of the piston 30 so as to be movable in the axial direction of the piston 30.

  According to the air damper 10a, the positioning of the seal ring 80 is not regulated. Therefore, when the piston 30a slides in the cylinder 20, as shown in FIGS. The whole can be moved in the axial direction of the piston 30a. In particular, when the piston 30 moves in the direction in which the braking force is released and the seal ring 80 moves toward the groove portion 41, the inner periphery of the seal ring 80 can be moved. The flow path formed through the groove portion 41 can be smoothly expanded, and the braking force applied to the piston can be released more quickly.

10, 10a Air damper 20 Cylinder 21 Blocking portion 22 Opening portion 25 Linear wall portion 30, 30a Piston 31 Seal surface 32 Orifice 33 Linear wall surface 39 Seal surface 41 Groove portion 43 Convex portion 45 First taper surface 47 Second taper surface 50 Rod 60 Cap 63 Insertion Hole 65 Insertion Portion 66 Slit 67 Locking Claw 73 Protrusion 75 First Tapered Surface 77 Second Tapered Surface 80 Seal Ring S1 Internal Space S2 External Communication Space

Claims (8)

A cylinder having a wall extending in a cylindrical shape, having a closed portion at one end and an opening at the other end;
A piston slidably inserted into the cylinder;
A rod connected to the piston and extending from an opening at the other end of the cylinder;
A flow passage that communicates the internal space surrounded by the closed portion of the cylinder and the piston to the outside;
When the piston slides in a direction away from or close to the closed portion of the cylinder, the flow path is narrowed to apply a braking force to the piston, and when the piston moves in the opposite direction, A braking force applying means for expanding the flow passage and releasing the braking force of the piston;
An air damper, wherein a cross section of the wall portion of the cylinder perpendicular to the axial direction has a cross-sectional shape having a major axis and a minor axis. The piston has a mounting surface to which a seal ring that is in close contact with the inner periphery of the wall of the cylinder is mounted, and a part of the mounting surface forms a linear wall surface extending in the longitudinal direction of the wall section of the cylinder. The linear wall surface is formed with a seal surface in close contact with the seal ring, and a groove portion that forms a flow path communicating with the cylinder on the inner periphery of the seal ring,
A portion of the seal ring that passes through at least the linear wall surface closes the flow path passing through the groove portion in close contact with the seal surface when the piston moves in a direction to receive the braking force, and the piston 2. The air damper according to claim 1, wherein the air damper is configured to open a flow path that passes through the groove portion away from the seal surface when moving in a direction in which the valve is released.   The air damper according to claim 1 or 2, wherein the seal ring has a circular shape in the absence of an external force before being attached to the piston.   The seal ring is a portion where the movement of the piston in the axial direction is restricted at both ends of the linear wall surface of the piston, and is located between both ends of the linear wall surface and passes through the linear wall surface. The air damper according to claim 2, wherein the air damper is configured to move in an axial direction of the piston to open and close a flow path passing through the groove. The piston conforms to the cross-sectional shape of the wall of the cylinder and has a cross-sectional shape having a major axis and a minor axis,
On the tip surface of the piston on the closed portion side of the cylinder, a convex portion is formed in a portion near at least one end in the major axis direction toward the direction of piston insertion into the cylinder,
The convex portion includes a first taper surface formed on both side surfaces in the short axis direction so as to become narrower in a direction in which the piston is inserted into the cylinder, and / or the other in the long axis direction of the piston. The air damper according to claim 1, further comprising a second tapered surface formed so as to be gradually lowered toward the end side.   The air damper according to claim 5, wherein the first tapered surface is a surface on which the second tapered surface is formed and reaches the side surface in the minor axis direction.   The air damper according to claim 5 or 6, wherein the convex portions are respectively provided at both ends of the front end surface of the piston in the major axis direction. A cap is attached to the other end opening of the cylinder opposite to the closed portion,
The cap has an insertion hole through which the rod is movably inserted, and an insertion portion to be inserted into the opening of the cylinder.
The insertion portion conforms to the cross-sectional shape of the wall portion of the cylinder, has a cross-sectional shape having a major axis and a minor axis, and is a distal end surface in the insertion direction to the cylinder, and has at least a major axis direction A convex part is formed in the part near the one end part toward the insertion direction into the cylinder,
The convex portion includes a first taper surface formed on both side surfaces in the short axis direction of the insertion portion so as to become narrower in a direction of insertion into the cylinder, and / or the insertion portion. The air damper according to any one of claims 5 to 7, further comprising a second tapered surface formed so as to gradually become lower toward the other end side in the major axis direction.