JP4484745B2 - Air damper - Google Patents

Description

  The present invention relates to an air damper suitable as an opening / closing damper for, for example, an automobile glove box.

  As this type of air damper, for example, as shown in Patent Documents 1 and 2 below, a cylindrical cylinder, a piston that moves in a sealed state within the cylinder, and one end of the cylinder connected to the piston are provided. There is a piston rod that protrudes and retracts from the opening, and either one of the cylinder and the piston rod is fixed to the support structure and controls the movement of the moving body that moves relative to the support structure. It has been.

In these air dampers, the piston and the piston rod are integrally formed of a thermoplastic elastomer, and it is not necessary to mount an O-ring or the like on the piston. Therefore, the structure can be simplified and the manufacturing cost can be reduced.
JP 2000-65116 A JP 2002-70910 A

  However, when the air damper is exposed to a high temperature atmosphere in a closed car for a long time when the solar radiation is strong, such as in the low latitude region, especially in a low latitude region, the seal protrusion of the piston formed of a thermoplastic elastomer is formed. Further, there is a possibility that thermal deformation is caused in a state where the cylinder is pressed against the inner periphery of the cylinder, the sealing performance is lowered, and the damper action is lowered.

  Therefore, an object of the present invention is to reduce the sealing performance due to the thermal deformation of the piston even if it is exposed to a high temperature atmosphere for a long time in an air damper having a piston and a piston rod formed of a resin having elasticity such as a thermoplastic elastomer. An object of the present invention is to provide an air damper which can be prevented.

  In order to achieve the above object, a first aspect of the present invention includes a cylinder having both ends opened, a seal cap attached to the rear end of the cylinder, a rod protruding from the front end of the cylinder, and the rod And a piston that slides in the cylinder when the rod is pushed, and the piston and the rod are integrally formed of an elastic resin, and an annular seal protrusion is formed on the piston. The inner circumference of the portion of the cylinder adjacent to the seal cap forms an enlarged diameter portion, and the inner circumference of the portion from the front end portion of the cylinder to the front of the seal cap slightly forms a reduced diameter portion, A taper portion extending from the enlarged diameter portion to the reduced diameter portion, and the seal projection of the piston includes a first seal projection located on the rear end side of the piston and the rod side The outer diameter of the first seal protrusion is larger than the inner diameter of the reduced diameter portion, and the outer diameter of the second seal protrusion is larger than the outer diameter of the first seal protrusion. The first seal projection is positioned at the enlarged diameter portion and the second seal projection is positioned at the reduced diameter portion in a state where the rod is fully pushed in. An air damper characterized by the above is provided.

  According to the above invention, when the rod is pushed and pulled and the piston slides in the cylinder, the space between the seal cap and the piston is pressurized or depressurized, and the air inside and outside the cylinder is provided in the narrow gap provided in the seal cap or the piston. Since it circulates through, braking action is given.

In the state where the rod is completely pushed in, the first seal protrusion of the piston is configured to be located at the enlarged diameter portion. Therefore, even if the rod is exposed to a high temperature atmosphere for a long time in this state, the first seal protrusion is Is not strongly pressed against the inner periphery of the enlarged diameter portion, and heat deformation is prevented. For this reason, even in a region where the interior of the vehicle is in a high temperature atmosphere, the sealing performance does not deteriorate due to thermal deformation, and the damper action can be stably maintained over a long period of time.
In addition, with the rod fully pushed in, the first seal protrusion having a large outer diameter is located in the enlarged diameter portion and the second seal protrusion having a small outer diameter is located in the reduced diameter portion, so that thermal deformation is effectively performed. Is prevented. In addition, during the initial operation of starting to pull out the rod by the second seal protrusion, even if the sealing performance between the first seal protrusion and the enlarged diameter portion is low, the sealing effect by the second seal protrusion disposed on the inner periphery of the reduced diameter portion, The braking force can be supplemented.

  According to a second aspect of the present invention, in the first aspect of the invention, the outer diameter of the first seal protrusion located in the enlarged diameter portion is smaller than the inner diameter of the enlarged diameter portion in a state where the rod is completely pushed in. It is intended to provide an air damper.

  According to the above invention, since the first seal protrusion of the piston is disposed through the gap with respect to the inner periphery of the enlarged diameter portion in a state where the rod is completely pushed in, thermal deformation in a high temperature atmosphere can be prevented more reliably. be able to.

  According to a third aspect of the present invention, there is provided the air damper according to the first or second aspect, wherein an outer diameter of the second seal protrusion is smaller than an inner diameter of the reduced diameter portion.

  According to the said invention, the thermal deformation of the 2nd seal protrusion can be prevented effectively, and the increase in the sliding resistance of a piston can be prevented.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the gap between the outer periphery of the first seal projection and the inner periphery of the enlarged diameter portion is in a state where the rod is completely pushed. The present invention provides an air damper that is larger than the gap between the outer periphery of the two seal protrusions and the inner periphery of the reduced diameter portion.

  According to the above invention, it is possible to reliably prevent the thermal deformation of the first seal protrusion that applies the main braking force, and to provide the braking force assisting function during the initial operation while also preventing the second seal protrusion from being thermally deformed as much as possible. Can be.

  According to a fifth aspect of the present invention, a cylinder having both ends opened, a seal cap attached to the rear end of the cylinder, a rod protruding from the front end of the cylinder, and the rod connected to the rod A piston that slides in the cylinder by the pushing movement of the cylinder, and the piston and the rod are integrally formed of an elastic resin, and the piston has an annular seal protrusion, The inner circumference of the portion adjacent to the seal cap forms an enlarged diameter portion, the inner circumference of the portion extending from the front end of the cylinder to the slightly forward side of the seal cap forms a reduced diameter portion, and the gap between them is from the enlarged diameter portion. A tapered portion that reaches the reduced diameter portion, and is configured such that a seal protrusion of the piston is positioned at the enlarged diameter portion in a state where the rod is fully pushed in, Each of which is a multi-cylinder with one end closed, and the rod is connected to the closed end surface, and the multi-cylinder includes at least an outermost cylinder having the seal protrusion and at least one of the cylinders located inside the cylinder. The present invention provides an air damper characterized in that a plurality of plate-like ribs are provided in the inside of a cylinder which is composed of two cylinders and which is located inside, with a gap therebetween.

  According to the above invention, since the outermost cylinder having the seal protrusion is easily elastically deformed by adopting the multiple cylinder structure, the sealing performance can be enhanced while reducing the slide resistance.

  In addition, since a plurality of plate-like ribs are provided in the inside of the cylinder located on the inside via gaps, it is possible to prevent the occurrence of sink marks and the like during molding, and the rod is fully pushed in The gap between the seal cap and the piston can be made as small as possible to increase the braking force during the initial operation.

  According to the present invention, the seal protrusion of the piston is positioned at the enlarged diameter portion in a state where the rod is completely pushed in, so that the seal protrusion can be maintained even if exposed to a high temperature atmosphere for a long time in that state. Is not strongly pressed against the inner periphery of the enlarged diameter portion, and heat deformation is prevented. For this reason, even in a region where the interior of the vehicle is in a high temperature atmosphere, the sealing performance does not deteriorate due to thermal deformation, and the damper action can be stably maintained over a long period of time.

Next, an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the air damper 10 is formed integrally with a cylindrical cylinder 20, a rod 40 that can be inserted into and retracted from the cylinder 20, and a rear end of the rod 40. The piston 50 includes a piston 50 that slides on the inner periphery of the cylinder 20 by pulling, and a seal cap 60 that is attached to the rear end opening 22 of the cylinder 20.

  Referring also to FIG. 2, the cylinder 20 has a front end opening 21 through which the rod 40 is inserted and a rear end opening 22 through which the seal cap 60 is mounted. A guide piece 23 that guides the slide of the rod 40 protrudes from the upper edge of the front end opening 21. A rib 23 a is formed on the periphery of the front end opening 21.

  An extension cylinder 24 having a diameter larger than that of the main body of the cylinder 20 is formed in the rear end opening 22 via a step portion 25. The extension cylinder 24 has a notch 26 into which a positioning piece 61 of a seal cap 60 described later is inserted and a locking hole 27 into which a locking piece 62 of the seal cap 60 is engaged at a predetermined interval in the circumferential direction. It is formed alternately.

  A pair of attachment pieces 28 project from the lower sides of the front and rear end portions of the cylinder 20, and attachment holes 29 for attachment to the vehicle body panel and the like are formed in these attachment pieces 28, respectively.

  In addition, the inner periphery of the portion adjacent to the seal cap 60 of the cylinder 20, that is, the portion in front of the extension cylinder 24 forms the enlarged diameter portion 30. Further, the inner circumference of the portion from the front end portion of the cylinder 20 to a position slightly ahead of the seal cap 60 forms a reduced diameter portion 31. A tapered portion 32 is formed between the enlarged diameter portion 30 and the reduced diameter portion 31.

  Referring also to FIG. 3, the rod 40 is composed of a wall portion 41 having a U-shaped cross section and reinforcing rib walls 42 disposed in the wall portion 41 at predetermined intervals in the axial direction. Has been. An attachment piece 43 is formed at the front end of the rod 40, and an attachment hole 44 for attachment to a glove box 70 and the like which will be described later is formed therein. A locking projection 45 is formed on the lower side of the base of the mounting piece 43, and the locking projection 45 engages with the rib 23a of the cylinder 20 described above to regulate the maximum pushing position of the rod 40. It is supposed to be.

  A piston 50 is integrally formed at the rear end of the rod 40. The piston 50 has a disk-like closed end face 51 connected to the rod 40. A multi-cylindrical structure in which an outermost cylinder 52 and an inner cylinder 53 are formed behind the closed end face 51 is formed. In this embodiment, a total of three inner cylinders 53 are arranged concentrically inside the outermost cylinder 52, and an annular groove 54 is formed between the cylinders. The plurality of inner cylinders 53 are connected in some places by plate-like ribs 55 as shown in FIG. The piston 50 has such a structure to prevent the occurrence of shrinkage or the like during molding, and the gap between the seal cap 60 and the piston 50 in a state where the rod 40 is completely pushed in is made as small as possible. The braking force during operation can be increased.

  A first seal protrusion 56 is formed on the rear end side of the outermost cylinder 52, and a second seal protrusion 57 is formed on the rod 40 side. The outer diameter of the first seal protrusion 56 is larger than the outer diameter of the second seal protrusion 57. Further, the outer diameter of the first seal protrusion 56 is smaller than the inner diameter of the enlarged diameter portion 30 of the cylinder 20 and larger than the inner diameter of the reduced diameter portion 31. Further, the outer diameter of the second seal projection 57 is made smaller than the inner diameter of the reduced diameter portion 31 of the cylinder 20. The first seal projection 56 of the piston 50 is located on the inner circumference of the enlarged diameter portion 30 and the second seal projection 57 is located on the inner circumference of the reduced diameter portion 31 with the rod 40 pushed in to the maximum extent. It has become. In this case, the gap C1 between the enlarged diameter portion 30 and the first seal projection 56 is set to be larger than the gap C2 between the reduced diameter portion 31 and the second seal projection 57.

  The first seal projection 56 is formed at the end of the outermost cylinder 52. Since the annular groove 54 is formed inside the outermost cylinder 52, the first seal protrusion 56 is easily bent inside. As a result, the sealing performance is improved.

  The rod 40 and the piston 50 described above are integrally formed of an elastic resin such as a thermoplastic elastomer.

  Referring also to FIG. 4, the seal cap 60 has a substantially disk-shaped substrate 63. As described above, the positioning piece 61 inserted into the notch 26 of the extension cylinder 24 of the cylinder 20 and the locking piece 62 engaged with the locking hole 27 of the extension cylinder 24 are provided on the periphery of the substrate 63. A plurality are alternately arranged in the circumferential direction. A seal flange 64 is integrally formed on the inner surface side of the substrate 63. Further, an orifice 65 is formed at the center of the substrate 63.

  FIG. 5 shows a state in which the rod 40 is completely pushed into the cylinder 20. At this time, the locking projection 45 formed on the front end portion of the rod 40 abuts on the rib 23a of the cylinder 20, and the maximum insertion position of the rod 40 is restricted. As described above, in this state, the first seal protrusion 56 of the piston 50 is located at the diameter-expanded portion 30 of the cylinder 20, and the second seal protrusion 57 of the piston 50 is located at the diameter-reduced portion 31 of the cylinder 20. . The seal flange 64 of the seal cap 60 is in close contact with the step portion 25 of the cylinder 20 and hermetically seals the rear end opening 22 of the cylinder 20.

Next, the operation of the air damper 10 will be described.
As shown in FIG. 8, the air damper 10 is used as a device for braking the opening and closing of a glove box 70 of an automobile, for example.

  The glove box 70 has a box shape having a front wall 71, a back wall 72, and both side walls (not shown), and a handle 73 is provided at the center of the upper side of the front wall 71. The glove box 70 is rotatably attached to an opening formed in the instrument panel of the automobile via a fulcrum 74 provided at the lower end.

  The air damper 10 is rotatably attached to the vehicle body panel via any one of the attachment holes 29 provided on the lower side thereof. Further, the front end portion of the rod 40 is rotatably attached to one side wall of the glove box 70 through the attachment hole 44. Then, as shown by an imaginary line in FIG. 8, when the glove box 70 is opened, the rod 40 is pushed out, and a braking force by the air damper 10 acts. Further, when the glove box 70 is closed, the rod 40 is pushed into the cylinder 20, and a braking force is also applied at this time.

  As shown in FIGS. 3B and 5, in the state where the glove box 70 is closed, the rod 40 is pushed into the cylinder 20 to the maximum extent, and the first seal protrusion 56 of the piston 50 is the enlarged diameter portion of the cylinder 20. 30 and the second seal protrusion 57 is disposed on the reduced diameter portion 31 of the cylinder 20. At this time, as described above, a gap C1 is provided between the outer periphery of the first seal projection 56 and the inner periphery of the enlarged diameter portion 30, and the outer periphery of the second seal projection 57 and the inner periphery of the reduced diameter portion 31 are provided. Is provided with a gap C2.

  For this reason, even if the interior of the vehicle is exposed to strong solar radiation and becomes a high temperature atmosphere, and the rod 40 and the piston 50 made of the thermoplastic elastomer are exposed to a high temperature state in which they are softened, the first seal protrusion 56 of the enlarged diameter portion 30 Since it is not in pressure contact with the inner periphery, thermal deformation of the first seal protrusion 56 is prevented. Similarly, since the second seal projection 57 is not strongly pressed against the inner periphery of the reduced diameter portion 31, thermal deformation is prevented. Since the first seal protrusion 56 is disposed with a relatively large gap C1 with respect to the inner periphery of the enlarged diameter portion 30, there is a possibility that the initial braking force at which the rod 40 starts to move is insufficient, but the second seal Since the protrusion 57 is disposed with a relatively narrow gap C2 with respect to the inner periphery of the reduced diameter portion 31, the braking force during this initial driving can be supplemented. Note that the gaps C1 and C2 are not necessarily required, and these protrusions contact the enlarged diameter portion 30 and the reduced diameter portion 31 to the extent that thermal deformation of the first seal projection 56 and the second seal projection 57 can be prevented. You may come in contact.

  FIG. 6 shows a state where the glove box 70 is opened and the rod 40 is pulled out from the cylinder 20. The first seal protrusion 56 of the piston 50 passes through the tapered portion 32 and is inserted into the reduced diameter portion 31 and is pressed against the inner periphery of the reduced diameter portion 31 to be hermetically sealed. For this reason, the space between the seal cap 60 and the piston 50 is decompressed, and the piston 50 moves while air flows in through the orifice 65 of the seal cap 60. At this time, the seal flange 64 of the seal cap 60 is in close contact with the step portion 25 of the cylinder 20 and seals the rear end opening 22 of the cylinder 20. As a result, a strong braking force acts on the drawn out rod 40, and the glove box 70 can be prevented from falling sharply and opening.

  FIG. 7 shows a state where the rod 40 is pushed into the cylinder 20 by closing the glove box 70. At this time, since the first seal projection 56 of the piston 50 is pressed against the inner periphery of the reduced diameter portion 31 of the cylinder 20, the space between the seal cap 60 and the piston 50 is compressed and pressurized. . However, at this time, since the seal flange 64 of the seal cap 60 is turned up to form a gap away from the step portion 25 of the cylinder 20, the air in the cylinder 20 is not only the orifice 65 but also the periphery of the seal flange 64. Therefore, the glove box 70 can be closed with a lighter braking force than when the glove box 70 is opened.

  In the air damper having a piston and a piston rod formed of a resin having elasticity such as a thermoplastic elastomer, the present invention can prevent deterioration of the sealing performance due to thermal deformation of the piston even when exposed to a high temperature atmosphere for a long time. It can be used as an air damper.

It is a disassembled perspective view which shows one Embodiment of the air damper by this invention. The cylinder of the air damper is shown, in which (a) is a side sectional view and (b) is a partially enlarged sectional view. The rod and piston of the air damper are shown, in which (a) is a side sectional view and (b) is a partially enlarged sectional view. It is side surface sectional drawing which shows the seal cap of the air damper. It is side surface sectional drawing of the same air damper. It is explanatory drawing of the state which pulls out a rod in the air damper. It is explanatory drawing of the state which pushes in a rod in the air damper. It is explanatory drawing which applied the air damper to the opening / closing mechanism of the glove box.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Air damper 20 Cylinder 21 Front end opening part 22 Rear end opening part 23 Guide piece 24 Extension pipe | tube 25 Step part 26 Notch part 27 Locking hole 28 Attachment piece 29 Attachment hole 30 Expanded diameter part 31 Reduced diameter part 32 Taper part 40 Rod 50 Piston 51 Closed end face 52 Outermost cylinder 53 Inner cylinder 54 Annular groove 55 Plate rib 56 First seal protrusion 57 Second seal protrusion 60 Seal cap 61 Positioning piece 62 Locking piece 63 Substrate 64 Seal flange 65 Orifice

Claims (5)

A cylinder with open ends,
A seal cap mounted on the rear end of the cylinder;
A rod protruding from the front end of the cylinder;
A piston coupled to the rod and sliding in the cylinder by the pushing of the rod;
The piston and the rod are integrally formed of an elastic resin,
An annular seal protrusion is formed on the piston,
The inner circumference of the portion adjacent to the seal cap of the cylinder forms an enlarged diameter portion, and the inner circumference of the portion that extends from the front end of the cylinder to the slightly front side of the seal cap forms a reduced diameter portion, and the space between them increases. It has a tapered part from the diameter part to the reduced diameter part,
The piston seal projection is composed of a first seal projection located on the rear end side of the piston and a second seal projection located on the rod side,
An outer diameter of the first seal protrusion is larger than an inner diameter of the reduced diameter portion, and an outer diameter of the second seal protrusion is smaller than an outer diameter of the first seal protrusion;
The air damper is configured such that the first seal protrusion is positioned at the enlarged diameter portion and the second seal protrusion is positioned at the reduced diameter portion in a state where the rod is completely pushed.   2. The air damper according to claim 1, wherein an outer diameter of the first seal protrusion located in the enlarged diameter portion is smaller than an inner diameter of the enlarged diameter portion in a state where the rod is completely pushed.   The air damper according to claim 1 or 2, wherein an outer diameter of the second seal projection is smaller than an inner diameter of the reduced diameter portion.   With the rod fully pushed in, the gap between the outer circumference of the first seal projection and the inner circumference of the enlarged diameter portion is greater than the gap between the outer circumference of the second seal projection and the inner circumference of the reduced diameter portion. The air damper according to any one of claims 1 to 3, wherein the air damper is also enlarged. A cylinder with open ends,
A seal cap mounted on the rear end of the cylinder;
A rod protruding from the front end of the cylinder;
A piston coupled to the rod and sliding in the cylinder by the pushing of the rod;
The piston and the rod are integrally formed of an elastic resin,
An annular seal protrusion is formed on the piston,
The inner circumference of the portion adjacent to the seal cap of the cylinder forms an enlarged diameter portion, and the inner circumference of the portion that extends from the front end of the cylinder to the slightly front side of the seal cap forms a reduced diameter portion, and the space between them increases. It has a tapered part from the diameter part to the reduced diameter part,
In a state where the rod is completely pushed in, the piston is configured such that a seal projection of the piston is located in the enlarged diameter portion,
The piston has a multi-cylinder whose one end is closed, and the rod is connected to the closed end surface. The multi-cylinder includes an outermost cylinder having the seal protrusion and a cylinder located inside the cylinder. An air damper, comprising at least two cylinders, wherein a plurality of plate-like ribs are provided in the inside of the cylinder located inside through a gap.

Images