JPH09315104A - Caster for chair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the stability of caster for chair when the chair is seated. SOLUTION: A frame 1 is formed by continuously forming an upper wall 2 and a side wall 3. A slider 10 is arranged along the side wall 3 so that it may move up and down, a spring 13 is set so that the upper wall 2 and the slider 10 are energized to move oppositely, and a wheel 17 is arranged to turn freely through a horizontal shaft 16. A gear part 8 is formed inside the wheel 17, and a pawl 19 is arranged at the frame 1. The pawl 19 engages with the gear part 18 when the upper wall 2 approaches the slider 10. When a person seats on a chair equipped with such a caster as constructed in this way, the frame 1 descends against the pressing force of the spring 13 to thereby the pawl 19 engages with the gear part 18, resulting in locking of rotation of the wheel 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a caster mainly attached to a leg of a chair, and more particularly to a caster whose wheels are locked when sitting down.

[0002]

2. Description of the Related Art In general, chairs with casters can be moved while sitting by sitting on the floor by sitting on the floor and stretching the knees. When a child who does not arrive is seated, there is a risk that the child may move against the will of the occupant or lose his balance and fall.

[0003]

SUMMARY OF THE INVENTION Therefore, the present invention
It is intended to provide a caster for a chair which is excellent in stability when sitting down.

[0004]

In order to solve the above-mentioned problems, the present invention forms a frame by continuously connecting an upper wall and a side wall, and provides a slider which can be moved up and down along the side wall. The upper wall and the slider are biased by springs in a direction in which they are separated from each other, and a wheel is rotatably provided on the slider via a horizontal shaft. A gear portion is formed inside the wheel, and the wheel is mounted on the frame. The configuration is such that a claw that engages with the gear portion when the wall and the slider approach each other is provided.

[0005]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in FIGS. 1 to 3, the frame 1
Is a wheel holding portion 4 in which an upper wall 2 and a pair of side walls 3 are continuously provided.
And a shaft insertion portion 6 having an insertion hole 5 penetrating in the vertical direction. The mounting shaft 7 is inserted through the insertion hole 5,
Is prevented from coming off from the insertion hole 5 by a collar 8 formed on the outer periphery thereof and a nut 9 screwed into the lower end portion. A threaded portion 7a is formed on the upper end of the mounting shaft 7, and by screwing this threaded portion 7a into the lower end surface of a chair leg (not shown), the frame 1 can be pivoted on the chair leg about the shaft 7. It is attached.

A slider 10 is located inside the wheel holding portion 4, and two ridges 11 are formed on both side surfaces of the slider 10. The protrusion 10 is slidably engaged with two vertically extending grooves 12 formed on the inner surface of the side wall 3, whereby the slider 10 can be moved up and down with respect to the frame 1. A spring 13 is provided between the upper wall 2 and the slider 10, and the spring 13 urges the upper wall 2 and the slider 10 in directions away from each other.

The slider 10 has a through hole 14 penetrating horizontally between both side surfaces thereof, and the side wall 3 has a long hole 15 vertically long.
And the shaft 16 is inserted into the insertion hole 14 and the elongated hole 15. Wheels 17 are attached to both ends of a shaft 16 projecting from the elongated hole 15 to both sides, and the wheels 17 are rotatable with respect to the slider 10.

A gear portion 18 is formed on the inner surface of the wheel 17, and side walls 3 are provided with pawls 19 projecting laterally. The claw 19 can be engaged with the gear portion 18 when the upper wall 2 and the slider 10 approach each other.

The chair equipped with the casters constructed as described above can be easily moved because the wheels 17 rotate when a person is not sitting on the chair. When a person sits down, as shown in FIG. 4, the frame 1 is lowered against the pressing force of the spring 13, the claw 19 is engaged with the gear portion 18, the rotation of the wheel 17 is locked, and the movement is blocked. To be done.

[0011]

As described above, when a person sits down on the chair equipped with the casters according to the present invention, the frame descends against the pressing force of the spring, the claw engages with the gear, and the wheel Since the rotation is locked, the chair does not move against the occupant's will and does not fall out of balance.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing a caster according to the present invention.

FIG. 2 is a vertical sectional side view of the above.

FIG. 3 is a vertical sectional front view of the same.

FIG. 4 is a vertical sectional side view showing a wheel lock state of the above.

[Explanation of symbols]

 1 frame 2 upper wall 3 side wall 10 slider 13 spring 16 shaft 17 wheel 18 gear part 19 claw

Claims (1)

[Claims] 1. A frame 1 in which an upper wall 2 and a side wall 3 are continuously provided.
And a slider 10 that can be moved up and down along the side wall 3.
In addition, the upper wall 2 and the slider 10 are urged by a spring 13 in directions away from each other, and a wheel 17 is rotatably provided on the slider 10 via a horizontal shaft 16. A caster for a chair, in which a gear portion 18 is formed on the inner side, and a pawl 19 that engages with the gear portion 18 when the upper wall 2 and the slider 10 approach each other on the frame 1 is provided.