JPH08105481A - Air damper - Google Patents

Abstract

PURPOSE: To cope with the fluctuation of a load by changing a brake force and to perform suitable braking. CONSTITUTION: By relatively moving a piston 12 within a cylinder 14, air in an air chamber flows through an orifice 48 and braking is applied on opening and closing operation of the lid of the globe box of an automobile. During movement of a piston 12, an O-ring 42 makes slide contact with the inner periphery of the cylinder 14 and a friction force between the O-ring 42 and the inner periphery of the cylinder 14 also exerts a brake force on a lid 46. The inner periphery of the cylinder 14 is gradually reduced in the direction of the other end (a right end) at the other end part. When a load exerted in one way (an arrow mark C) of the piston 12 is increased at the other end part of the cylinder 14, a friction force between the O-ring 42 and the inner periphery of the cylinder 14 is increased at a reduced part 54 at the other end part, a brake force is increased by an amount equivalent to the increase of the friction force, and smooth coping with the fluctuation of a load is practicable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder type air damper for braking by allowing a piston to relatively move in a cylinder to flow air in an air chamber in the cylinder through an orifice.

[0002]

2. Description of the Related Art As an air damper of this type, for example,
Some are used for automobile glove boxes.

That is, in the air damper, one end of the cylinder is the bottom and the other end is closed by the cap, and the piston rod extends through the cap to the outside of the cylinder.
The piston is provided with an O-ring, and the O-ring is fitted in a concave portion annularly provided on the outer circumference of the piston and is in contact with the inner circumference of the cylinder. The chamber is partitioned and formed (the first air chamber is formed on one end side of the cylinder, and the second air chamber is formed on the other end side of the cylinder).

The piston is provided with an orifice which connects the front and rear sides (the first air chamber and the second air chamber) in the moving direction.

Further, the recess allows the O-ring to move relative to the piston along the direction of movement of the piston, and when the piston changes its moving direction from one end to the other end of the cylinder from one direction to the other, it becomes the O-ring. When the O-ring is moved from the first position to the second position by the frictional force with the inner circumference of the cylinder, and conversely when the piston changes the moving direction from the opposite direction to the one direction, the O-ring is moved to the first position by the frictional force. Move from position 2 to position 1. A groove is formed at the bottom of the recess, and the O-ring is the second
When in the position, the first air chamber and the second air chamber communicate with each other through the groove, and when the O-ring is in the first position,
The groove is closed.

When the piston moves in one direction, air flow is performed at the orifice, and the braking force is exerted based on the flow resistance at the orifice. Conversely, when the piston moves in the opposite direction, air escapes through the groove, reducing braking.

When such an air damper is used in a glove box, the piston rod is connected to the lid of the glove box, the cylinder is connected to the storage side of the glove box, and the piston rod is pulled out from the cylinder when the lid is opened. The piston is adapted to move in one direction from one end of the cylinder to the other. As a result, when the lid is opened, the opening operation is slowed down so that no impact is generated. On the contrary, when closing the lid, the closing action is prompt.

[0008]

When the lid of the glove box is opened from the vertical state to the horizontal state, the load exerted on the piston in one direction gradually increases as the lid opens (the load varies). The lid opening speed becomes faster. Therefore, as the lid approaches the open limit position, the braking force by the air damper becomes insufficient. At the open limit position of the lid, it may bounce due to reaction and smooth opening operation cannot be obtained.

The present invention has been made in view of the above facts, and an object thereof is to provide an air damper that changes a braking force to cope with a change in load and obtains a suitable braking.

[0010]

In order to solve the above-mentioned problems, the air damper of the present invention according to claim 1 is provided with a seal member in contact with the inner circumference of the cylinder on the outer circumference of the piston to form an air chamber in the cylinder. Then, in the air damper that causes the air to flow through the orifice by the piston relatively moving in the cylinder between the one end and the other end of the cylinder to perform braking, the cylinder inner diameter at the other end of the cylinder is A reduced diameter portion gradually reduced toward the other end of the cylinder is provided. At the reduced diameter portion, the friction force between the seal member and the inner circumference of the cylinder increases as the piston moves to the other end of the cylinder. It is characterized by the configuration.

According to a second aspect of the present invention, in the air damper of the first aspect, the cylinder is formed in a bottomed cylindrical shape having the other end as a bottom and the one end opened, and the open one end is a cap. It is characterized by being blocked by.

According to a third aspect of the present invention, in the air damper of the first aspect, the orifice is provided in the piston, communicates both front and rear sides in the moving direction of the piston, and is opened regardless of the moving direction of the piston. In addition, the piston is also provided with an opening / closing hole that communicates the front and rear sides in the moving direction of the piston, and the sealing member is formed of an O-ring, and the first position and the second position with respect to the piston are formed along the moving direction of the piston. The opening / closing hole is closed at the first position and the opening / closing hole is opened at the second position so that the piston moves in one direction from the one end to the other end of the cylinder. When the direction changes from the opposite direction to the opposite direction, the piston moves from the first position to the second position based on the frictional force between the seal member and the inner circumference of the cylinder, and the piston moves in the opposite direction from the opposite direction. When the direction is changed, the frictional force causes the movement from the second position to the first position, and the air flows through the orifice without letting the air escape from the opening / closing hole, thereby braking the piston and moving the piston in the one direction. It is characterized in that the piston is moved in the opposite direction by reducing the braking by moving it and letting air escape from the opening / closing hole.

According to a fourth aspect of the present invention, in the air damper of the second aspect, the piston rod of the piston penetrates the bottom of the cylinder and extends to the outside of the cylinder, and the open end of the cylinder is hermetically closed with a cap. Be embodied.

[0014]

According to the above construction, the piston moves relatively in the cylinder, whereby the air in the air chamber flows through the orifice, and the braking is performed.

When the piston moves, the seal member is in sliding contact with the inner circumference of the cylinder, and the frictional force between the seal member and the inner circumference of the cylinder also gives a braking force.

When the piston moves from one end of the cylinder to the other end and the seal member reaches the reduced diameter portion of the other end of the cylinder, the seal moves as the piston moves to the other end of the cylinder thereafter. The frictional force between the member and the inner circumference of the cylinder increases.

The increase in the frictional force between the seal member and the inner circumference of the cylinder is achieved by increasing the pressure contact force between the seal member and the inner circumference of the cylinder, and at a predetermined position in the moving section of the piston, that is, It is possible at the end point of movement of the piston. For example, when the load applied to one direction of the piston increases when the piston is located at the other end of the cylinder, the seal member is attached to the other end of the cylinder where the load applied to the piston in one direction increases. The frictional force between the cylinder and the inner circumference of the cylinder increases, and the frictional force increases, so that the braking force increases and it is possible to cope with the load fluctuation.

In this way, the braking force can be changed to cope with the change in the load, and suitable braking can be obtained.

According to the second aspect of the present invention, the other end of the cylinder is a bottom and the other end is open so as to have a bottomed cylindrical shape, and the reduced diameter portion is formed on the bottom side of the cylinder. Molding of the reduced diameter portion becomes easy.

A third aspect of the present invention is a so-called one-way type air damper, and the braking force is reduced by the movement of the piston in the opposite direction. Therefore, for example, the movement of the piston in the opposite direction does not require that much braking. It is effective in all cases.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an air damper according to the present invention will be described below with reference to FIGS.

As shown in FIGS. 1 and 3, the air damper 1
At 0, the piston 12 moves inside the cylinder 14 along the axial direction of the cylinder 14 (left-right direction in FIG. 1).
4 can be relatively reciprocated between one end (the left end in FIG. 1) and the other end (the right end in FIG. 1). The cylinder 14 is composed of a bottomed cylindrical cylinder body 18 having one end open and a bottom 16 at the other end, and a cap 20 closing the open end. The cap 20 has a cylindrical shape with a bottom,
The engaging hole 22 provided in the peripheral surface of the cap 20 is provided with the engaging projection 24 provided correspondingly to the outer peripheral surface of the cylinder body 18.
Is elastically engaged with and mounted. Cap 20
An O-ring 26 is provided between the cylinder body 18 and the cylinder body 18 to ensure airtightness of a first air chamber 44, which will be described later. A split groove 28 is formed at the open end of the cap 20 to facilitate the engagement of the engagement protrusion 24 with the engagement hole 22.

As shown in FIGS. 4 and 5, the piston 12
Is coaxial with the cylinder 14 and has a bottomed cylindrical shape with one end side of the cylinder 14 open and the bottom 30 on the other end side.
One end of a piston rod 32 is connected to the bottom 30 of the piston 12. The piston rod 32 has a long plate shape,
The piston rod 32 is located coaxially with the cylinder 14, and the other end of the piston rod 32 extends through the through hole 34 in the bottom 16 of the cylinder 14 to the outside of the cylinder 14.

The outer circumference of the piston 12 has a shape in which large diameter portions 36, 38 are provided at both ends in the axial direction, and an annular recess 40 is formed between the large diameter portions 36, 38. An O-ring 42 formed of an elastic material such as rubber made of synthetic resin, which serves as a sealing member, is fitted in the recess 40, and the large diameter portions 36 and 38 are formed.
The O-ring 42 is in contact with the inner circumference of the cylinder 14 in a state where a gap is formed between the outer circumference of the cylinder 14 and the inner circumference of the cylinder 14, and inside the cylinder 14, both sides of the piston 12 in the axial direction (the moving direction of the piston 12). Air chambers 44 and 46 are formed on both sides). That is, the first air chamber 44 is formed on one end side of the cylinder 14, and the second air chamber 46 is formed on the other end side of the cylinder 14.

The bottom 30 of the piston 12 has axially opposite sides (first air chamber 44 and second air chamber 46) of the piston 12.
An orifice (small hole) 48 that communicates with the () is provided.

On the other hand, in the recess 40, the O-ring 42
Is movable in the axial direction (width direction of the recess 40) with respect to the piston 12, and the moving range is restricted by contact with a large diameter portion (first large diameter portion) 36 on one end side of the cylinder 14. First
Between the position (the position shown in FIG. 5) and the second position (the position shown in FIGS. 1 and 4) in which the contact is restricted by the large diameter portion (second large diameter portion) 38 on the other end side of the cylinder 14. . When the piston 12 changes its moving direction from one end of the cylinder 14 to the other end (indicated by an arrow C in the drawing) to the opposite direction (from the other end of the cylinder 14 to one end), O-ring 4
2 by the frictional force between the inner circumference of the cylinder 14 and the piston 12
Regardless of the movement of the piston 14, the piston 12 is substantially immovable along the moving direction of the piston 12, and moves relative to the piston 12 from the first position to the second position.
It is held in the second position by 2 successive movements in the opposite direction. Conversely, when the piston 12 changes its moving direction from the opposite direction to the one direction, the friction force between the O-ring 42 and the inner circumference of the cylinder 14 moves the piston 12 relative to the cylinder 14 regardless of the movement of the piston 12. It becomes substantially immobile along the direction and moves relative to the piston 12 from the second position to the first position and is retained in the first position by continued movement of the piston 12 in one direction.

Further, a groove 52 is formed in the bottom of the recess 40 along the width direction of the recess 40 so as to cut out a part of the second large diameter portion 38 and communicate with the cutout 50. The groove 52 is
It extends to the middle of the recess 40 in the width direction and does not reach the first large diameter portion 36. When the O-ring 42 is in the second position, the O-ring 42 is located in a portion of the recess 40 where the groove 52 exists.
2, a groove is formed between the groove 52 and the second air chamber 46 through the notch 50, and the groove 52 is exposed on the first large diameter portion 36 side of the O-ring 42 on the other hand. First large diameter portion 36
Through the gap between the outer circumference of the cylinder and the inner circumference of the cylinder 14.
It communicates with the air chamber 44. When the O-ring 42 is in the first position, the O-ring 42 is located in the recessed portion 40 where there is no groove 52, and the other of the grooves 52 cannot be exposed to the first large-diameter portion 36 side of the O-ring 42, and thus the first air chamber. The groove 52 does not allow the 44 and the second air chamber 46 to communicate with each other. The groove 52 constitutes an opening / closing hole that is closed by movement of the piston 12 in one direction and opened by movement of the piston 12 in the opposite direction. In this embodiment, the groove 52 is formed at two places in the recess 40.

As shown in FIGS. 2 and 5, a reduced diameter portion 54 is formed at the other end of the cylinder 14. In the reduced-diameter portion 54, the inner diameter of the cylinder 14 is gradually reduced toward the other end of the cylinder 14, and the inner circumference of the cylinder 14 in a portion other than the reduced-diameter portion 54 is formed as a straight surface. The inner circumference of the cylinder 14 in the reduced diameter portion 54 is formed by a tapered surface.

The O-ring 42 makes sliding contact with the inner circumference of the cylinder 14 as the piston 12 moves, and a frictional force acts between the O-ring 42 and the inner circumference of the cylinder 14. This frictional force is constant when the O-ring 42 is on the straight surface, but when the O-ring 42 is on the reduced diameter portion 54 which is the Taber surface, the frictional force is directed from the piston 12 to the other end of the cylinder 14. It increases according to.

The opening / closing hole formed by the groove 52 is larger than the hole diameter of the orifice 48. Piston 12
When moving in one direction, the air flow between the air chambers 44 and 46 is performed by the orifice 48, and the braking force is exerted based on the flow resistance of the air passing through the orifice 48.
Braking works. On the contrary, when the piston 12 moves in the opposite direction, the air flow across the air chambers 44 and 46 is mainly
Done through the groove 52, the air is allowed to escape through the groove 52, reducing the braking force and reducing the braking.

At one end of the cylinder 14, the outer circumference is
A mounting piece 56 is provided so as to project, and a mounting hole 58 is formed in the mounting piece 56. Further, a mounting hole 60 is formed at the extending tip of the piston rod 32.

In a glove box of an automobile using the air damper 10 thus constructed (in FIG. 8, two glove boxes 62 and 68 are shown above and below,
The upper glove box 62 will be described), FIG.
And, as shown in FIG. 7, a lid 64 as a movable member of the glove box 62 is rotatably supported on the storage portion 66 side of the glove box 62 by a rotating shaft 65 at the lower end thereof, and is in a vertical state (see FIG. 6) and the horizontal state (state of FIG. 7).

The cylinder 14 is accommodated in the accommodating portion 66 of the glove box 62 via the attachment hole 58 of the attachment piece 56.
The piston rod 32 is supported by the lid 64 of the glove box 58 via the mounting hole 60 and is rotatable about the mounting hole 60. .

When the lid 64 is closed and in the vertical state, the piston rod 32 is retracted into the cylinder 14 and the piston 12 is located at one end of the cylinder 14. As shown in FIG. 7, as the lid 64 opens from the vertical state (indicated by the one-dot chain line in FIG. 7) in the direction of the arrow D, the piston rod 32 is pulled out from the cylinder 14, and the piston 12 moves once inside the cylinder 14. From one direction to the other end. In the horizontal position where the lid 64 is completely opened (indicated by a chain double-dashed line in FIG. 7), the piston 12 moves to the cylinder 1
Located at the other end of 4.

According to the above construction, the piston 12 moves relatively in the cylinder 14 so that the air chamber 4
The air of 4, 46 flows through the orifice 48, and the opening / closing operation of the lid 64 is braked.

When the piston 12 moves, the O-ring 42 makes sliding contact with the inner circumference of the cylinder 14, and the frictional force between the O-ring 42 and the inner circumference of the cylinder 14 also gives a braking force to the lid 64.

When the piston 12 moves from one end of the cylinder 14 toward the other end and the O-ring 42 reaches the reduced diameter portion 54 of the other end of the cylinder 14, the piston 12 thereafter moves to the other end of the cylinder 14. The frictional force between the O-ring 42 and the inner circumference of the cylinder 14 increases as it moves to.

The frictional force between the O-ring 42 and the inner circumference of the cylinder 14 is increased by increasing the pressure contact force between the O-ring 42 and the inner circumference of the cylinder 14.
2 at a predetermined position in the movement section, that is, the piston 12
This can be done at the end point of movement (end point of opening operation). As the lid 64 rotates and approaches the horizontal position from the vertical position, the load exerted by the lid 64 in one direction of the piston 12 gradually increases. In this way, the load exerted on the piston 12 in one direction is applied to the other end of the cylinder 14 by the piston 12.
When the piston 12 has a large load in one direction, the frictional force between the O-ring 42 and the inner circumference of the cylinder 14 increases at the other end of the cylinder 14 where the load applied to the piston 12 in one direction increases. As the frictional force increases, the braking force increases, and it is possible to smoothly cope with load fluctuations. At the open limit position (horizontal position) of the lid 64, the lid 64 can be smoothly opened without bouncing.

In the reduced diameter portion 54, as shown in FIGS.
Shows the taper angle θ and the axial length L of the reduced diameter portion 54.
Is appropriately set so as to be able to appropriately cope with the fluctuation of the load.

Since the other end of the cylinder body 18 is the bottom 16 and one end is open, and the reduced diameter portion 54 is formed on the bottom side of the cylinder body 18, the reduced diameter portion 54 of the cylinder 14 is formed. Will be easier.

Further, according to the so-called one-way type air damper in which the braking is effective by the movement of the piston in one direction and the braking is reduced by the movement of the piston in the opposite direction, the opening operation is slowed when the lid 64 is opened. As a result, when the lid 64 is closed, it is effective in the case where the closing operation is performed promptly without requiring so much braking.

In the above embodiment, the air damper is applied to the glove box of the automobile, but the invention is not limited to this.
For example, the present invention can be applied to other things such as an opening / closing cover of an operation panel of a television or the like.

Further, in the above embodiment, the lid as the movable member is connected to the piston side, but conversely, the lid may be connected to the cylinder side.

[0044]

As described above, according to the air damper of the present invention, the braking force can be changed to cope with the variation of the load, and a suitable braking can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of an air damper of the present invention, as seen from the direction of arrow A in FIG.

FIG. 2 is a view corresponding to FIG. 1, showing a state in which a piston is located at the other end of the cylinder.

FIG. 3 is an exploded perspective view showing an air damper of the present embodiment.

FIG. 4 is an enlarged cross-sectional view showing a part of an air damper of the present embodiment and showing a state in which a piston is located at one end of a cylinder, as seen from the direction of arrow B in FIG.

5 is an enlarged cross-sectional view showing a part of the air damper of the present embodiment and showing a state where the piston is located at the other end of the cylinder, as seen from the direction of arrow B in FIG.

FIG. 6 is a diagram showing the air damper of this embodiment applied to a glove box of an automobile.

FIG. 7 is a view corresponding to FIG. 6, showing a state of the air damper when the lid of the glove box is opened.

FIG. 8 is a perspective view showing a glove box of an automobile.

[Explanation of symbols]

 10 Air Damper 12 Piston 14 Cylinder 16 Bottom 20 Cap 32 Piston Rod 42 O-Ring (Seal Member) 44 First Air Chamber (Air Chamber) 46 Second Air Chamber (Air Chamber) 48 Orifice 52 Groove (Opening / Closing Hole) 54 Reduced Diameter Section

Claims (4)

[Claims] 1. A seal member, which is in contact with the inner circumference of the cylinder, is provided on the outer circumference of the piston to form an air chamber in the cylinder, and the piston relatively moves in the cylinder between one end and the other end of the cylinder. In an air damper that causes air to flow through an orifice to perform braking, at the other end of the cylinder, a reduced diameter portion is provided in which the cylinder inner diameter is gradually reduced toward the other end of the cylinder. An air damper, wherein the frictional force between the seal member and the inner circumference of the cylinder increases as the cylinder moves to the other end. 2. The air damper according to claim 1, wherein the cylinder is formed in a bottomed cylinder shape having the other end as a bottom and the one end being opened, and the open one end is closed with a cap. 3. The orifice is provided in the piston, communicates with the front and rear sides of the piston in the moving direction, and is opened regardless of the moving direction of the piston. The seal member is formed of an O-ring and is movable relative to the piston between a first position and a second position along a moving direction of the piston. The opening / closing hole is closed at the second position and the opening / closing hole is opened at the second position. When the moving direction of the piston changes from one direction from the one end of the cylinder to the other direction, the seal member and the inner circumference of the cylinder are separated from each other. Based on the frictional force between them, the first position moves to the second position, and when the moving direction of the piston changes from the opposite direction to the one direction, the second force moves to the first position based on the frictional force. By moving air through the orifice without letting air escape from the opening / closing hole, braking is effected to move the piston in the one direction, and by letting air escape from the opening / closing hole to reduce braking, the piston is The air damper according to claim 1, wherein the air damper is moved in the opposite direction. 4. The air damper according to claim 2, wherein the piston rod of the piston extends through the bottom of the cylinder to the outside of the cylinder, and the open end of the cylinder is hermetically closed with a cap.