JPH09108062A - Gas spring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a tube, a spring member, etc., of a gas spring from being broken by rotational force and to improve durability. SOLUTION: A spring member 35 is positioned in a recessed part 24 for storing a sprig of a guiding member 21 and is arranged between the guiding member 21 and an elevating/lowering member 25 and the elevating/lowering member 25 is restricted in the rotational direction to the guiding member 21 and is movably arranged only in the axial direction. Therefore, when a person sit on the chair leaves from the seat part, even if a gas spring 13 rotates, the elevating/lowering member 25 only elevates and lowers in the axial direction along the guiding member 21 and a rotational force can be prevented from being generated in the spring member 35. In addition, as the rotational force does not act on the spring member 35, it does not bite a tube 14 and in addition, when the spring member 35 is stretched and contracted, abnormal sound and breakage can be prevented from being generated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas spring device suitable for use in, for example, a chair whose height can be adjusted.

[0002]

2. Description of the Related Art Generally, in order to improve the sitting comfort when sitting on a chair, a structure in which a seat is supported by a gas spring device is widely used. Is, for example,
Those described in Japanese Patent No. 5975, etc. are known.

Here, a chair using this type of gas spring device is a support cylinder standing on a post and is inserted into the support cylinder, and the free end of its piston rod is the lower end of the support cylinder. A gas spring that is rotatably attached to the upper end of the tube and is fixed to the seat by leading the upper end of the tube out of the upper end of the support cylinder, and is fixedly provided in the support cylinder.
A fixing member having an inclined surface on the upper surface and having the tube inserted through the central hole so as to be rotatable and movable in the axial direction, and an inclined surface provided on an upper portion of the fixing member and matching the inclined surface of the fixing member on the lower surface. A rotating member having the tube inserted therein so as to be fixed in the central hole in the rotational direction and movable in the axial direction; and a guide provided on the upper portion of the support cylinder body for rotatably supporting the tube. It is composed of a member and a spring member interposed between the guide member and the rotating member.

When seated on the seat, the gas spring acts as a cushion to improve the sitting comfort. Further, when the seat portion is rotated, the rotating member rotates together with the tube of the gas spring, and the inclined surface of the rotating member is displaced from the inclined surface of the fixed member. At this time, since the rotating member is pressed against the fixed member by the spring member, a force for matching the inclined surfaces acts between the rotating member and the fixed member. Therefore, even if the seat portion is rotated, the seat portion is returned to the position where the inclined surface of the rotating member and the inclined surface of the fixed member match, that is, the original position.

[0005]

In the prior art described above, when the seat portion rotates with respect to the post, the tip side of the inclined surface of the rotating member slides on the inclined surface of the fixed member. A large force acts on the tip side of the inclined surface of the rotating member. The rotating member is attached so as to rotate integrally with the tube of the gas spring, and the force acting on the tip end side of the inclined surface of the rotating member acts as a force to twist the tube. There is a possibility that the outer peripheral surface of the may be damaged, and there is a problem that durability is reduced.

Further, since the lower portion of the spring member is in contact with the rotating member which rotates with respect to the support cylinder, and the urging force thereof is constantly acting, the rotating member rotates when the seat portion is rotated. Accordingly, the spring member also tries to rotate. However, since the spring member is interposed between the guide member provided on the upper part of the support cylinder and the rotating member, it cannot follow smoothly the rotation of the rotating member, and the spring member Twisted.
As a result, the spring member is violent in the support cylinder, abnormal noise is generated due to the violence, the spring member is damaged in an early stage, and the spring member and the guide member come into contact with the spring member. The problem of surface damage arises.

The present invention has been made in view of the above-mentioned problems of the prior art, and a gas spring device for preventing the tube and spring member of the gas spring from being damaged by a rotational force and improving the durability. Is intended to provide.

[0008]

In order to solve the above-mentioned problems, a gas spring device adopted by the present invention is a support cylinder and a piston rod which is inserted into the support cylinder and whose one side in the axial direction is a piston rod. And a retractable gas spring that is attached to the support cylinder and has a tube on the other side in the axial direction that protrudes outside the support cylinder, and is fixedly provided in the support cylinder, and the inner peripheral side of the gas spring is A guide member provided with a guide hole for movably guiding the tube in the rotational direction and the axial direction and having a spring accommodating concave portion on the other side in the axial direction, and an outer peripheral side positioned in the spring accommodating concave portion of the guide member. Direction, the inner peripheral side serves as a guide hole for movably guiding the tube of the gas spring in the rotational direction and the axial direction, and an elevating member having an inclined surface formed on the other side in the axial direction. The above Inner circumferential side together provided to guide the movable only in the rotational direction to the other side of the lifting cylinder engages the tube of the gas spring becomes engaging hole to rotate integrally,
A rotating member having an inclined surface formed on one side in the axial direction so as to come into contact with and separate from the inclined surface of the elevating member according to the rotation of the tube, and the guide member located in the spring accommodating recess of the guide member. And a lifting member, and a spring member that urges the tilted surface of the lifting member and the tilted surface of the rotating member in a direction in which they come into contact with each other.

With the above structure, since the elevating member is located in the spring accommodating recess of the guide member and is guided so as to be movable only in the axial direction, even if the elevating member moves up and down, the tip ends of the inclined surfaces of the elevating member and the rotating member. The force acting on the side does not twist the tube.

Further, since the spring member is provided between the guide member and the elevating member and provided in the spring accommodating recess, even if the elevating member moves up and down by the rotation of the rotating member, the spring member responds to this movement. It only expands and contracts and does not rotate.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS.

In the drawings, reference numeral 1 denotes a gas spring device according to an embodiment of the present invention, which is applied to a chair 2, and a post 3 of the chair 2 is provided on one side in the axial direction thereof. The seat portion 4 is provided on the other side in the axial direction.

Reference numeral 11 denotes a cylindrical support cylinder which constitutes the gas spring device 1. A cap 12 is fixedly provided on one side of the support cylinder 11 in the axial direction, and an opening is provided on the other side in the axial direction. doing.

Reference numeral 13 is a gas spring inserted in the support cylinder 11 in the axial direction. The gas spring 13 is, for example, a hexagonal tube 14 and a piston slidably fitted in the tube 14 (see FIG. (Not shown) and a piston rod 15 fixed to the piston and having a free end and protruding outside the tube 14. The piston rod 15 is constantly urged in the extension direction by the gas enclosed inside. Has been done.

Here, the gas spring 13 projects a tube 14 from the support cylinder 11 to the other side in the axial direction, and a seat portion 4 is attached to the projecting end thereof, while a piston rod 15 located on the one side in the axial direction. Is attached to the cap 12. And, at the tip of the piston rod 15,
As shown in FIG. 2, a washer 16 is attached, a cushioning rubber 17 is provided on the washer 16, and a thrust washer 18 is provided on the opposite surface thereof.
Moreover, the stopper pin 19 prevents the cap 12 from being pulled out. Reference numeral 20 is a valve provided on the protruding end of the tube 14, and the length of the gas spring 13 is changed by operating the valve 20 with a lever (not shown) provided on the seat portion 4 or the like. It is designed to adjust the height of.

Reference numeral 21 is a guide member provided in the support cylinder 11, and the guide member 21 is a cylinder adapted to the inner diameter of the support cylinder 11, and is fixed to the support cylinder 11 by a retaining pin 22 in the axial direction. It is fixed in the direction of rotation. The guide member 21 may be fixed by caulking the support cylinder 11 from the outside without fixing it with the stop pin 22.

Here, on the inner peripheral side of the guide member 21,
As shown in FIG. 3, a guide hole 23 that forms a circumscribed circle with respect to the tube 14 is provided, and the guide hole 23 guides the tube 14 movably in the axial direction and the rotation direction. Further, a bottomed spring accommodating recess 24 is provided on the other side in the axial direction of the guide member 21, and the spring accommodating recess 24 has a spring member 35 to be described later.
Is arranged so that it can expand and contract. Further, as shown in FIG. 4, detent grooves 24A, 24A are formed on the inner peripheral surface of the spring accommodating recess 24 so as to face each other by 180 degrees.

Reference numeral 25 denotes an elevating member that is movable only in the axial direction within the spring accommodating recess 24 of the guide member 21, and is provided on the outer peripheral side of the elevating member 25 on the inner peripheral surface of the spring accommodating recess 24. Engagement protrusion 2 that engages with the detent grooves 24A, 24A
5A and 25A are provided. Also, the lifting member 25
A guide hole 26 that forms an circumscribed circle with respect to the tube 14 is provided on the inner peripheral side of the tube 14, and the tube 14 is movably guided in the rotation direction and the axial direction by the guide hole 26. Therefore, the lifting member 25 is movable only in the axial direction regardless of the rotation of the tube 14.

Further, 27 is an inclined surface formed on the other side surface in the axial direction of the elevating member 25, and the inclined surface 27 comes into contact with and separates from an inclined surface 34 formed on a rotating member 28 described later. ing.

Reference numeral 28 denotes a rotary member located on the other axial side of the support cylinder 11 and adjacent to the elevating member 25. A flange portion 28A is formed on the other axial side of the rotary member 28. There is. Here, the rotary member 28 is supported in the rotational direction by a radial bearing 29, and the radial bearing 29 is arranged between the inner peripheral surface on the other side of the support cylinder 11 and the outer peripheral surface of the rotary member 28. ing. The radial bearing 29
Is for smoothing the rotation of the rotary member 28, and is not always necessary when the rotary member 28 is made of a material having a low frictional resistance, such as resin. The rotary member 28 is axially supported by a thrust bearing 30, and the thrust bearing 30 is connected to the end surface of the flange portion 28A and the other open end of the support cylinder 11 via a washer 31 and a retaining ring 32. It is arranged between. The retaining ring 32
Instead of this, the other open end of the support cylinder 11 may be stopped by curling or caulking.

Further, an engaging hole 33 is provided on the inner peripheral surface of the rotating member 28, and the engaging hole 33 is a hexagonal shape engaging with the outer circumference of the tube 14 of the gas spring 13, as shown in FIG. The tube 14 is integrally rotated with the rotation of the tube 14 via the radial bearing 29 and the thrust bearing 30. On the other hand, when the tube 14 is displaced in the axial direction, the rotating member 28 allows the engagement hole 33 to displace the tube 14 in the axial direction.

Further, 34 is an inclined surface 34 formed on the other side in the axial direction of the rotating member 28, and the inclined surface 34 comes into contact with and separates from the inclined surface 27 of the elevating member 25. As a result, when the rotary member 28 rotates, the inclined surfaces 27 and 34 come into contact with and separate from each other, thereby displacing the elevating member 25 in the axial direction.

Reference numeral 35 is a spring member provided in the spring accommodating recess 24 of the guide member 21, and the spring member 35 is elastically provided between the bottom of the spring accommodating recess 24 and one end surface of the elevating member 25. Configured as a compressed spring. The spring member 35 urges the inclined surface 27 of the elevating member 25 and the inclined surface 34 of the rotating member 28 in a direction in which they are always in contact with each other.

The gas spring device according to this embodiment is constructed as described above, and its operation will be described below.

First, when the chair 2 is used, when adjusting the height thereof, the gas spring 13 is extended or contracted by operating the lever provided on the seat portion 4 to adjust the height. adjust. In addition, the weight of the seat portion 4 reduces the size of the gas spring 13, which acts as a cushion.

Here, in order to leave the seat portion 4 from the seated state, when the seat portion 4 is rotated, the gas spring 13 is rotated.
Rotate integrally with each other, and since the engaging hole 33 of the rotating member 28 is engaged with the tube 14, the gas spring 13
Rotate with. At this time, since the rotating member 28 is supported by the radial bearing 29 and the thrust bearing 30, the rotating member 28 can smoothly rotate without resistance.

As the rotating member 28 rotates in this manner, the inclined surface 34 of the rotating member 28 presses the inclined surface 27 of the elevating member 25 in a direction separating from the elevating member 25 against the spring member 35. And urge it downward.
Therefore, the elevating member 25 has its engaging projection 25A engaged with the detent groove 24A of the spring accommodating recess 24, and
Since the guide hole 26 is movable in the axial direction and the rotation direction with respect to the tube 14, the elevating member 25 moves downward in the spring accommodating recess 24 of the guide member 21. And
When the rotating member 28 is rotated by approximately 180 degrees, the elevating member 25 descends to the state shown in FIG.

When the user leaves the seat 4 in this state, the elevating member 25 is urged upward by the spring force of the spring member 35 toward the rotating member 28, causing a slip between the inclined surfaces 27 and 34, and the elevating member 25. Moves upward to a position where the inclined surfaces 27 and 34 come into contact with each other, and stops at a position where the inclined surfaces 27 and 34 come into contact with each other. As a result, the seat portion 4 has returned to the original position. It should be noted that, even when the rotary member 28 together with the gas spring 13 is rotated by 180 degrees or more by the seat portion 4, the elevating member 25 is raised in the direction in which the inclined surface 27 and the inclined surface 34 come close again, which is the same as the above. .

Thus, in the gas spring device according to this embodiment, the spring member 35 is located in the spring accommodating recess 24 of the guide member 21, and is disposed between the guide member 21 and the elevating member 25. The elevating member 25 is restricted in the rotational direction with respect to the guide member 21 and is arranged so as to be movable only in the axial direction.

As a result, when the person sitting on the chair 2 leaves the seat portion 4, the elevating member 25 only displaces in the axial direction despite the rotation of the gas spring 13, and therefore the spring member. Even if the elevating member 25 is displaced at 35, its rotational force is not generated. Therefore, even if a compressive force is applied to the spring member 35, the durability can be improved without applying a torsional force to the spring member 35, and even if the elevating member 25 moves up and down, the elevating member 25 and the rotating member 28 are inclined. Surface 2
The force acting on the distal ends of the tubes 7 and 34 does not twist the tube 14, and the outer peripheral surface of the tube 14 can be prevented from being damaged.

The spring member 35 is disposed between the guide member 21 and the elevating member 25 so as to be displaceable only in the axial direction and does not displace in the rotational direction. It is not necessary to provide a low resistance sliding member such as a sliding bearing or a thrust bearing on one end surface of the lifting member 25. Therefore, even if the elevating member 25 is displaced, the spring member 35 does not generate an abnormal noise when it is displaced, and the spring member 35 is not damaged, and the durability can be improved.

Further, since the spring member 35 is arranged in the spring accommodating recess 24 of the guide member 21 and its movement in the radial direction is restricted, even if the seat portion 4 of the chair 2 is rotated in any direction, It is possible to prevent buckling deformation of the spring member 35 and the like without the spring member 35 violently moving in the spring accommodating recess 24.

In the above embodiment, the tube 14 is not limited to the hexagonal shape, but may be a non-circular shape such as a polygonal shape other than the hexagonal shape or an ellipse, or a projection extending in the axial direction on the outer peripheral side of the tube. Alternatively, a groove may be provided to engage with the rotating member.

In the above embodiment, the post 3 is provided on one side of the gas spring device 1 in the axial direction, but the post is eliminated and the supporting cylinder of the gas spring device is directly fixed to the floor surface. You may

[0035]

As described above in detail, according to the present invention, when the tube of the gas spring is rotated with respect to the support cylinder, the rotating member engaged with the tube through the engaging hole is integrally rotated. Then, since the inclined surface of the rotating member presses the inclined surface of the elevating member in the direction of separating, the elevating member separates from the rotating member against the biasing force of the spring member. When the external force that is rotating the tube is removed, the rotating member is rotated so that the inclined surface of the elevating member is brought into contact with the inclined surface of the rotating member by the urging force of the spring member. It can be returned to its original position. At this time, the lifting member is guided by the guide member so as to be movable only in the axial direction,
Since it is possible to prevent a rotational force from acting on the elevating member and the spring member, the spring member violates due to the rotational force when the tube is rotated, and abnormal noise is generated, or a gas spring, an elevating member, a spring member, etc. Can be prevented from being damaged, and the durability of the gas spring device can be improved.

[Brief description of the drawings]

FIG. 1 is a partially broken external view showing a chair using a gas spring device of the present invention.

FIG. 2 is an enlarged longitudinal sectional view showing a gas spring device in FIG. 1;

3 is a cross-sectional view taken along the line III-III in FIG.

4 is a cross-sectional view taken along the line IV-IV in FIG.

5 is a cross-sectional view taken along the line VV in FIG.

FIG. 6 is a vertical cross-sectional view showing the gas spring device in a state in which the tube is rotated approximately 180 degrees from the original position, as viewed from the same position as in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gas spring device 11 Support cylinder 13 Gas spring 14 Tube 15 Piston rod 21 Guide member 23, 26 Guide hole 24 Spring accommodation recess 25 Elevating member 27, 34 Inclined surface 28 Rotating member 33 Engaging hole 35 Spring member

Claims (1)

[Claims] 1. A support cylinder and a cylindrical body inserted into the support cylinder, one side in the axial direction being a piston rod attached to the support cylinder, and the other axial side being a tube outside the support cylinder. A projecting and retractable gas spring, and a guide hole that is fixedly provided in the support cylinder and that guides the tube of the gas spring rotatably in the rotational direction and the axial direction and the other side in the axial direction. A guide member provided with a spring accommodating concave portion, an outer peripheral side of which is positioned in a spring accommodating concave portion of the guide member and is guided so as to be movable only in an axial direction to move up and down, and an inner peripheral side of the tube of the gas spring in a rotational direction. An elevating member that serves as a guide hole for movably moving in the axial direction, and an inclined surface is formed on the other side in the axial direction, and an inner peripheral side that is provided on the other side of the support cylinder so as to be movably guided only in the rotational direction. The gas sp Member that forms an engaging hole that engages with the tube of the ring and rotates integrally, and has an inclined surface formed on one side in the axial direction that abuts against and separates from the inclined surface of the elevating member according to the rotation of the tube. And a spring member which is located in the spring accommodating recess of the guide member, is provided between the guide member and the elevating member, and urges the inclined surface of the elevating member and the inclined surface of the rotating member into contact with each other. A gas spring device composed of and.