JP3584997B2 - Front tilting device in chair - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a chair used for office work and the like, wherein a seat plate thereof can be tilted forward against a coil spring.
[0002]
[Prior Art and Problems to be Solved by the Invention]
Japanese Patent Application Laid-Open No. 2-19103 discloses that a chair used for office work or the like has a seat plate capable of tilting forward against a coil spring.
However, this prior art is not configured such that the coil spring for the forward tilt of the seat plate cannot be adjusted, and the elasticity of the coil spring for the forward tilt of the seat plate can be adjusted to the weight of the seated person. I can't do it, so I'm not comfortable sitting.
[0003]
Japanese Unexamined Utility Model Publication No. Sho 62-109646, which is another prior art, proposes a configuration in which a coil spring can be adjusted with respect to forward tilting of a seat plate. Since the adjustment is performed by turning, there is a problem that the adjustment cannot be quickly performed with a light force.
The present invention is able to adjust the coil spring against the front tilting of the seat plate, with a relatively light force, it is an technical problem to be able to quickly.
[0004]
[Means for Solving the Problems]
In order to achieve this technical object, the present invention provides a fixing frame attached to an upper end of a column standing upright from a leg, and a seat plate is pivotally attached to the fixing frame so as to be tiltable forward, and the seat In a chair comprising a coil spring for forward tilting of a seat plate interposed between a lower surface side and an upper surface side of the fixed frame body, a coil disposed on a front side of the seat plate with respect to the pin shaft for pivotal attachment. through the pair of spring receiving member for supporting the upper and lower ends of the spring, and the adjusting lever shaft inserted in the coil spring is inserted so as to protrude from the lower surface downward through the fixed frame body, this The upper end of the adjustment lever shaft is pivotally attached to the seat plate so as to be rotatable, and the adjustment lever shaft is pivotally attached to the seat plate at a portion of the upper surface of the fixed frame through which the adjustment lever shaft passes. The arc surface having the center point at a position shifted by an appropriate distance from the There was formed so as to extend in the rotational direction of the adjusting lever axis, this arcuate surface, a recess lower spring receiver member with respect to the fixed frame of said coil spring is freely fits engagement detachable circumferential Are provided at a plurality of locations along the line .
[0005]
[Operation]
In this configuration, by rotating the adjustment lever shaft about the pivotal connection portion to the seat plate, together with the adjustment lever shaft, the coil spring and the spring receiving body also pivot on the adjustment lever shaft with respect to the seat plate. It rotates around the attachment portion, and rotates so that the lower spring receiver for the coil spring fits into and engages with any of the recesses provided on the circular arc surface of the fixed frame.
[0006]
In this case, the arc surface of the fixed frame body is formed with a center point at a position displaced by an appropriate distance from the pivotal attachment portion of the adjustment lever shaft to the seat plate, so that each of the arc surfaces provided on the arc surface is formed. Since the distance between the recess and the pivot portion of the adjusting lever shaft with respect to the seat plate is different for each of the recesses, the rotation of the adjusting lever shaft causes the lower spring receiving body for the coil spring to move. By fitting into and engaging with an arbitrary recess, the elasticity of the coil spring with respect to the forward tilting of the seat plate can be arbitrarily increased or decreased, and can be fixed in the adjusted state.
[0007]
【The invention's effect】
Therefore, according to the present invention, there is an effect that the adjustment of the spring with respect to the forward tilting of the seat plate can be performed extremely simply and quickly by rotating the adjusting lever shaft.
[0008]
【Example】
An embodiment of the present invention will be described below with reference to FIGS.
In this figure, reference numeral 1 denotes a leg of a chair, and a fixed frame 3 is fixed to an upper end of a column 2 erected from the leg 1, and an upper surface of the fixed frame 3 has a seat on the upper surface. A seat plate receiving plate 5 to which the plate 4 is attached is pivotally mounted via a pin shaft 6 so that the seat plate 4 can freely tilt forward.
[0009]
Reference numeral 7 denotes a portion between the upper surface side of the fixed frame body 3 and the lower surface side of the seat plate receiving plate 5 on the front side of the pin shaft 6 with respect to the forward tilt of the seat plate 4. The upper part of this coil spring 7 is provided with an upper spring receiving body 8 and the lower end thereof is provided with a lower spring receiving body 9. In addition, on the upper surface of the rear end portion of the fixed frame 3, a shock-absorbing stopper body 10 made of rubber or the like with which the rear end portion of the seat plate receiving plate 5 contacts is attached. The rear end portion of the seat plate receiving plate 5 is constantly urged by the coil spring 7 so as to be in contact with the stopper body 10.
[0010]
Reference numeral 11 denotes an adjusting lever shaft, and the adjusting lever shaft 11 is inserted into the coil spring 7 so that the adjusting lever shaft 11 penetrates through the fixed frame 3 and projects downward from the lower surface thereof. Then, the upper end 11a of the adjustment lever shaft 11 is rotatably pivoted to a boss 5a formed on the lower surface of the seat plate receiving plate 5.
The upper spring receiving member 8 at the upper end of the coil spring 7 slides freely on the outer peripheral surface of the boss portion 5a of the seat plate receiving plate 5 in the rotating direction of the adjustment lever shaft 11. In the upper surface of the fixed frame 3, the adjusting lever shaft 11 penetrates into a portion through which the adjusting lever shaft 11 penetrates by a distance L from the pivotal attachment portion 11a of the adjusting lever shaft 11 to the seat plate receiving plate 5. An arc surface 12 having a center point O and having a radius R at a shifted portion is formed so that the arc surface 12 extends in the rotation direction of the adjustment lever shaft 11, and a plurality of recesses are formed in the arc surface 12. 13 are provided at appropriate intervals along the circumferential direction, and a projection 9 a provided on the lower spring receiving body 9 at the lower end of the coil spring 7 is detachably fitted into and engaged with the recess 13. To be configured.
[0011]
In this configuration, the adjustment lever shaft 11 is rotated from the state shown by the solid line to the state shown by the one-dot chain line or the two-dot chain line around the pivotal connection portion 11a with respect to the seat plate receiving plate 5, thereby performing this adjustment. Along with the lever shaft 11, the coil spring 7 also has a fixed frame body in which the protrusion 9 a of the lower spring receiving body 9 for the coil spring 7 is centered on the pivotally attached portion 11 a of the adjustment lever shaft 11 to the seat plate receiving plate 5. 3 is rotated so as to fit into and engage with an arbitrary one of the recesses 13 provided on the circular arc surface 12.
[0012]
In this case, the circular arc surface 12 of the fixed frame 3 has an arc surface of a radius R having a center point O at a position displaced by a proper distance L from the pivotal attachment portion 11a of the adjustment lever shaft 11 to the seat plate receiving plate 5. The distance between each of the recesses 13 provided on the arcuate surface 12 and the pivotal connection portion 11a of the adjusting lever shaft 11 with respect to the seat plate receiving plate 5 is different for each of the recesses 13. Therefore, by the rotation of the adjustment lever shaft 11, the projection 9 a of the lower spring receiving body 9 with respect to the coil spring 7 is fitted into and engaged with an arbitrary recess 13, so that the coil against the forward tilting of the seat plate 4 is formed. The elasticity of the spring 7 can be arbitrarily increased or decreased, and can be fixed in the adjusted state.
[0013]
It should be noted that the seat plate receiving plate 5 in the above-described embodiment may be omitted, and the seat plate 4 may be directly pivotally attached to the fixed frame 3. The upper spring receiver 8 with respect to the upper end of the coil spring 7 slides freely on the outer peripheral surface of the boss portion 5a of the seat plate receiving plate 5 in the rotation direction of the adjustment lever shaft 11. By adopting a configuration in which contact is made so as to obtain, there is an advantage that the turning operation of the adjustment lever shaft 11 can be performed with a lighter force and that the coil spring 7 can be prevented from being twisted.
[Brief description of the drawings]
FIG. 1 is a front view of a chair according to an embodiment of the present invention.
FIG. 2 is an enlarged view of a main part of FIG.
FIG. 3 is a sectional view taken along line III-III of FIG. 2;
[Explanation of symbols]
REFERENCE SIGNS LIST 1 leg 2 support 3 fixed frame 4 seat plate 5 seat plate receiving plate 6 pin shaft 7 coil spring 8, 9 spring receiver 11 adjustment lever shaft 12 arc surface 13 recess

Claims (1)

A fixed frame is attached to the upper end of a column standing upright from the leg, and a seat plate is pivotally attached to this fixed frame so as to be tiltable forward. In the meantime, in a chair comprising a coil spring for forward tilting of the seat plate,
The adjustment lever shaft that penetrates a pair of spring receivers that support the upper and lower ends of a coil spring disposed on the front side of the seat plate with respect to the pin shaft for pivoting, and that is inserted into the coil spring, is fixed. Insert so as to penetrate the frame and project downward from the lower surface ,
The upper end of the adjusting lever shaft is pivotally connected to the seat plate so as to be rotatable, and the adjusting lever shaft is pivotally connected to the seat plate at a portion of the upper surface of the fixed frame through which the adjusting lever shaft penetrates. An arc surface having a center point at a position deviated from the attachment portion by an appropriate distance is formed so that the arc surface extends in the rotation direction of the adjustment lever shaft, and a fixing frame body for the coil spring is formed on the arc surface. A plurality of recesses along which a lower spring receiving member is detachably fitted and engaged with the lower spring receiving body in a circumferential direction.

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