JP6998679B2 - Chair - Google Patents

Description

The present invention relates to a chair in which the front-back position of the backrest can be adjusted.

For example, there is a chair for children / students in which the front-back position of the backrest can be adjusted according to the size of the body (or according to the growth), and an example thereof is disclosed in Patent Document 1. That is, the chair of Patent Document 1 is a system in which the seat is rotatably supported by leg struts, and the backrest is fixed to the lower surface portion of the seat by a pair of left and right connecting support rods (frame materials).

The connecting support rod has a front-rear and longitudinal horizontal portion located on the lower surface portion of the seat, and a strut portion rising from the rear end thereof, and a backrest is attached to the strut portion. On the other hand, the horizontal part of the left and right connecting support rods is inserted into the connecting board that projects downward on the lower surface of the seat so that it can move back and forth. By pressing the horizontal portion of the connecting support rod, the horizontal portion of the connecting support rod is held so as not to be able to move back and forth. When the handle is loosened, the horizontal part of the connecting support rod can slide back and forth, and the front and back position of the backrest can be changed.

CD-ROM of Jitsukaihei 4-9142

If the backrests are attached to the left and right frame materials as in Patent Document 1, the backrests can be stably supported with a simple structure, but in Patent Document 1, since the left and right connecting boards are provided with handles, the front and rear of the backrests There is a problem that it takes time and effort to adjust the position. There are also safety concerns as it is possible to forget to tighten one of the handles.

In addition, since the horizontal part of the frame material is pressed by the tip of the screw shaft provided on the handle, it is difficult to secure the strength of the frame material unless it is a bar material, and therefore it is difficult to use a lightweight pipe material. Therefore, there was a problem that the cost was high and it was difficult to reduce the weight.

The invention of the present application has been made to improve such a situation.

The chair of the present invention is
" It has a seat supported by a leg device and a backrest fixed to the lower surface of the seat via a pair of left and right frame members.
The frame material has a front-rear longitudinal portion arranged on the lower surface portion of the seat and a strut portion integrally provided at the rear end of the front-rear longitudinal portion, and the backrest is attached to the strut portion. The front-rear longitudinal portion is inserted into a guide cylinder fixed to the lower surface portion of the seat so as to be movable back and forth.
In addition, the left and right front and rear longitudinal portions of the frame material are simultaneously pressed and held by the clamp body from below . "
It is a basic configuration.

In the invention of claim 1, in the above basic configuration,
"The clamp body is formed horizontally horizontally, and its left and right ends serve as pressing portions pressed by the front and rear longitudinal portions of the frame material, and screw shafts provided on the rotary handle are inserted from below in the left and right middle portions. And
Further, the clamp body is formed with an upward protrusion that engages with the lower surface portion of the seat or the guide cylinder to hold the clamp body so that it cannot be swiveled horizontally. "
It has the feature.

The invention of claim 2 is claimed in claim 1.
"The upward protrusion of the clamp body is engaged with the lower surface portion of the seat by the posture holding means including the positioning pin and the positioning hole."
It is configured as.

The invention of claim 3 is claimed in claim 1 or 2.
" The left and right guide cylinders are formed with cutout holes that expose the front and rear longitudinal portions of the frame material downward, and the clamp body abuts from below on the front and rear longitudinal portions exposed from the notch holes. Is there "
It is configured as.

The invention of claim 4 is claimed in claim 3.
" A receiving plate is fixed to the lower surface of the seat, the guide cylinder is fixed to the receiving plate, and a nut for screwing the screw shaft of the handle is provided, and the handle has a certain degree. It is set so that it can be unscrewed only within a range, and the receiving plate, the guide cylinder, or the clamp body is formed with a posture holding means for holding the clamp body non-rotatably within a range in which the handle can be unscrewed. "
It is configured as.

In the present invention, since the front and rear longitudinal portions of the left and right frame materials are pressed by one clamp body, the front and rear positions of the backrest can be quickly adjusted, and there is no forgetting to fix the backrest, so that the work is reliable. Are better.

Further, since the front-rear width of the clamp body can be arbitrarily set, even if the front-rear longitudinal portion is made of a pipe, the pressing force per unit area can be lowered to strongly press the clamp body without deformation . Therefore, it is easy to make the frame material by vibe, and as a result, it can contribute to cost reduction and weight reduction.

As an operation method of the clamp body, for example, by operating the cam body or the wedge body by rotating the lever, it is also possible to press or release the front and rear longitudinal portions of the frame material against the member. However, if a method of clamping with a rotary handle with a screw shaft is adopted as in the present invention , the front and rear longitudinal portions of the frame material can be firmly pressed and fixed by the clamp body without considering wear, so that the reliability is excellent. ing. Further, in the present invention, the clamp body can be prevented from rotating with the rotation of the handle by the upward protrusion, and the fixing of the frame material can be ensured.

When the configuration of claim 3 is adopted, the front-rear longitudinal portion of the frame material is pressed against the guide cylinder at the notch hole, and is also pressed against the guide cylinder on both the front-rear and front-rear sides sandwiching the notch hole. The front-rear longitudinal portion of the material can be pressed and fixed to the guide cylinder in a wide range in the front-rear direction. Therefore, high pressing strength can be ensured.

When a notch hole is formed in the guide cylinder as in claim 3, if the clamp body comes off from the notch hole, the front and rear longitudinal portions of the frame material cannot be pressed even if the handle is screwed in, resulting in improper fixing. Will end up. In this regard, if the posture holding means is provided as in claim 4, the clamp body is held in a posture of fitting into the notch hole even if the handle is loosened, so that fixing failure can be prevented.

In the present invention, the front-rear longitudinal portion can be in an inclined posture in which the height increases toward the rear. With this configuration, the height of the backrest from the seat surface increases as it moves backward, so that the height of the backrest can be automatically adjusted according to the height of the user.

It is an overall perspective view of the chair which concerns on 1st Embodiment. It is a figure which shows the 1st Embodiment, (A) is a front view, (B) is a side view. It is a bottom view of the 1st Embodiment. It is a figure which shows the 1st Embodiment, (A) is the main part separation perspective view, (B) is the partial perspective view in the state which turned over. FIG. 3 is a sectional view taken along line V-V of FIG. It is sectional drawing of 2nd Embodiment. (A) is a bottom view of the main part of the third embodiment, and (B) is a bottom view of the main part of the fourth embodiment.

(1). First Embodiment Next, an embodiment of the present invention will be described with reference to the drawings. First, the first embodiment shown in FIGS. 1 to 5 will be described.

As shown in FIG. 1, the chair includes a leg device 1, a seat 2, and a backrest 3. The leg device 1 includes a leg strut 4 made of a gas cylinder and a group of branch legs that support the leg support 4, and a caster is provided at the tip of each branch leg. Therefore, the chair of the present embodiment is a swivel chair whose height of the seat 2 can be adjusted by unlocking the leg struts with a lever. Further, the chair of the present embodiment is used by a child / student as a set with a learning desk, and a footrest 5 is attached to the leg device 1.

As shown in FIGS. 2 and 3, a bottom viewing angle receiving plate 7 is fixed to the upper end of the leg support 4 via a square frame-shaped bracket 6, and a seat 2 is fixed to the upper surface of the receiving plate 7. .. Therefore, the receiving plate 7 constitutes the lower surface portion of the seat 2. A sleeve to which the upper end portion of the leg support 4 is fitted is fixed to the bracket 6 by welding. The pedestal 4 is arranged substantially in the center of the seat 2 in a plan view.

As is clearly shown in FIG. 5, the seat 2 has a structure in which a cushion material 9 is stretched on the upper surface of a seat plate 8 made of wood or the like and covered with a skin material, while the receiving plate 7 has a seat plate 8 on its left and right sides. The portion between the left and right polymerization portions 7a is a separation portion 7b with a certain distance (space) from the seat plate 8. That is, the receiving plate 7 is formed in a downward convex shape when viewed from the front. As shown in FIG. 5, the polymerization portion 7a is fixed to the seat plate 8 by a plurality of screws 10.

As shown in FIG. 2, the backrest 3 is fixed to the receiving plate 7 via the left and right frame members 11, and the frame members 11 have a horizontal front-rear longitudinal portion 11a and a front-rear longitudinal portion 11a located below the seat 2. It has a support column portion 11b that rises from the rear end, and as shown in FIG. 3, for example, the front-rear longitudinal portion 11a is fitted in a guide cylinder 12 fixed to the receiving plate 7 by welding so as to be slidable back and forth. .. The frame material 11 and the guide cylinder 12 are manufactured of a round pipe such as a circular steel pipe. Needless to say, the left and right front-rear longitudinal portions 11a and the guide cylinder 12 are arranged in parallel.

The upper ends of the left and right strut portions 11b are integrally connected, and the integrally connected portions have an arcuate shape. Although not shown, the backrest 3 has a structure in which a cushioning material is stretched on the back plate and covered with a skin material, and the support column portion 11b is fixed to the back plate with screws or the like. The lower part of the support column 11b is curved so as to project backward in a side view. This is so that the backrest 3 can be moved to the top of the seat 2. Further, the rear end portions of the left and right front and rear longitudinal portions 11a are connected by the left and right horizontally long reinforcing stays 14.

As shown in FIG. 3, the guide cylinder 12 is fixed to the rear portion of the receiving plate 7 substantially behind the leg support 4, and the front-rear longitudinal portion 11a of the frame material 11 is exposed in front of the guide cylinder 12. .. A split pin 13 is inserted through the front end of the front-rear longitudinal portion 11a as an example of preventing it from coming off. As shown in FIGS. 4 and 5, the guide cylinder 12 is welded to the connecting portion between the separated portion 7b and the overlapping portion 7a of the receiving plate 7.

A rectangular notch hole 15 that partially exposes the front-rear longitudinal portion 11a of the frame material 11 is formed in the front-rear intermediate portion of the left-right guide cylinder 12, and the front-rear and rear parts of the frame material 11 are formed at the notch hole 15. By pressing the longitudinal portion 11a from below with the left and right ends of the clamp body 16, the frame material 11 is fixed so as not to be able to move back and forth. Therefore, the left and right ends of the clamp body 16 are pressing portions that press the front-rear longitudinal portions 11a.

The clamp body 16 is made of resin (may be a die-cast product) and has a horizontally long shape. A screw shaft 18 provided on a circular handle 17 is inserted into the left and right middle portions, and the screw shaft 18 is a receiving plate 7. It is screwed to the nut 19 fixed by welding to the upper surface of the detached portion 7b in the above. The clamp body 16 is provided with left and right upward protrusions 16a that are in contact with or close to the inner side surface of the guide cylinder 12, and a positioning pin 20 is provided at the upper end of the upward protrusions 16a, while the receiving plate 7 is provided. A positioning hole 21 into which the positioning pin 20 is fitted is formed in the detached portion 7b of the above. The posture holding means is composed of the positioning pin 20 and the positioning hole 21.

As shown in FIG. 5, a snap ring 22 for preventing the screw shaft 18 from coming out of the nut 19 is provided at the upper end of the screw shaft 18 in the handle 17. The snap ring 22 is an example of a stroke regulating means that defines a screw-back range of the handle 17, and is set so that the moving stroke of the screw shaft 18 is smaller than the fitting stroke between the positioning hole 21 and the positioning pin 20. ing.

Therefore, even if the handle 17 is screwed back to the maximum limit, the clamp body 16 does not rotate together with the handle 17 because the positioning pin 20 is fitted in the positioning hole 21. As a result, with the handle 17 loosened, the left and right ends of the clamp body 16 are always in a posture of overlapping the notch holes 15, and the frame material 11 can be securely held and fixed by screwing the handle 17.

That is, the clamp body 16 rotates with the screw back of the handle 17, and the clamp body 16 hits the guide cylinder 12 without hitting the front-rear longitudinal portion 11a from the notch hole 15 in the state where the handle 17 is screwed. It is possible to prevent the situation where the fixing is defective due to being left unattended. Even if the handle 17 is fully screwed in, the upper end of the upward protrusion 16a of the clamp body 16 does not stretch against the receiving plate 7 (otherwise, the clamp cannot be clamped). It is also possible to integrally connect the left and right upward protrusions 16a to form one protrusion.

As a posture holding means for preventing the accompanying rotation of the clamp body 16, for example, upward positioning pieces are provided on both front and rear edges of the notch hole 15, and the left and right ends of the clamp body 16 are positioned between the front and rear positioning pieces. It is also possible to say that. In this case, it is not necessary to form the posture holding means on the clamp body 16.

Since the front-rear longitudinal portion 11a of the frame material 11 is pressed by the clamp body 16 with a certain amount of front-rear length, the pressing force per unit area is set to be equal to or less than the strength limit even if the front-rear longitudinal portion 11a is made of a pipe. It can be formed and is not deformed by the pressing of the clamp body 16. Therefore, the pipe can be used for the frame material 11 without impairing the fixing function, and the cost and weight can be reduced.

When the notch holes 15 are formed in the front and rear intermediate portions of the guide cylinder 12 as in the present embodiment, the pressing force of the clamp body 16 can be applied substantially evenly to the total length of the guide cylinder 12, so that the clamp body 16 is highly fixed. There is an advantage that strength can be secured.

(2). Other Embodiments Next, the other embodiments shown in FIGS. 6 and 7 will be described. The second embodiment shown in FIG. 6 is another example of the posture holding means. In this embodiment, as the posture holding means (rotation prevention means) of the clamp body 16, guide cylinders 12 are provided on the left and right ends of the clamp body 16. A side upward protrusion 23 that abuts or is close to the outer side surface is projected upward.

The side upward protrusion 23 projects upward from the inner upward protrusion 16a and is in contact with or in close proximity to the outer surface of the guide cylinder 12 within the rotatable range of the handle 17. Therefore, it is possible to prevent the clamp body 16 from rotating with the handle 17 when the handle 17 is loosened. It is more preferable to maintain the state in which the guide cylinder 12 is sandwiched between the upward protrusion 16a and the side upward protrusion 23 from both inside and outside within the rotatable range of the handle 17. Further, when the front-rear length of the side upward protrusion 23 is made larger than the front-rear width of the clamp body 16, the posture stability of the clamp body 16 is further improved.

FIG. 7 shows another example of the relationship between the clamp body 16 and the guide cylinder 12. Of these, in the third embodiment shown in FIG. 7A, the guide cylinder 12 is separated into two front and rear parts, and the clamp body 16 is arranged at a portion between the front and rear guide cylinders 12. Also in this embodiment, the front-rear longitudinal portion 11a of the frame material 11 can be stably pressed and fixed by the clamp body 16.

In the fourth embodiment shown in FIG. 7B, the guide cylinder 12 is formed in a cylinder in the range on the rear side of the clamp body 16, and is cut open downward in the range on the front side of the clamp body 16 to form a gutter. Is forming. Also in this embodiment, since the front-rear longitudinal portion 11a is pressed against the guide cylinder 12 within the range of both front and rear sides of the clamp body 16, the same fixing strength as in the first embodiment can be secured.

When the seated person leans against the backrest 3, a moment that pushes the rear portion downward acts on the front-rear longitudinal portion 11a of the frame material 11, and this moment is supported by the rear end of the guide cylinder 12. Therefore, even if the front side of the clamp body 16 is cut open as in the fourth embodiment, the support strength of the body pressure by the backrest 3 does not decrease.

Although some embodiments of the present invention have been described above, the present invention can be embodied in various ways. For example, it is also possible to form a surface of the clamp body that presses the front-rear longitudinal portion of the frame material into an arc surface having a radius of curvature equal to the outer diameter of the front-rear longitudinal portion. In this case, since the clamp body comes into surface contact with the front-rear longitudinal portion, the stress acting on the front-rear longitudinal portion can be reduced and the frame material can be thinned. It is also possible to fix the guide cylinder to the lower surface of the seat plate.

The clamp body can also be formed in an H shape when viewed from the bottom. The frame material does not necessarily have to be circular, and may be a polygon such as a hexagon or an ellipse. Furthermore, the invention of the present application does not exclude the use of a bar as the frame material.

The invention of the present application can be embodied in a chair. Therefore, it can be used industrially.

1 Leg device 2 Seat 3 Backrest 4 Leg support 7 Support plate that constitutes the lower surface of the seat 7a Overlapping part 7b Separation part 8 Seat plate 11 Frame material 11a Front and rear longitudinal parts 11b Support part 12 Guide tube 15 Notch hole 16 Clamp body 16a Upward protrusion 17 Handle 18 Screw shaft 19 Nut 20 Positioning pin that constitutes the posture holding means 21 Positioning hole that constitutes the posture holding means
23 Side upward protrusions constituting the posture holding means

Claims (4)

It has a seat supported by a leg device and a backrest fixed to the lower surface of the seat via a pair of left and right frame members.
The frame material has a front-rear longitudinal portion arranged on the lower surface portion of the seat and a strut portion integrally provided at the rear end of the front-rear longitudinal portion, and the backrest is attached to the strut portion. The front-rear longitudinal portion is inserted into a guide cylinder fixed to the lower surface portion of the seat so as to be movable back and forth.
Moreover, the left and right front and rear longitudinal portions of the frame material are simultaneously pressed and held by the clamp body from below .
The clamp body is formed horizontally horizontally, and its left and right end portions serve as pressing portions pressed by the front and rear longitudinal portions of the frame material, and screw shafts provided on the rotary handle are inserted from below in the left and right middle portions. And
Further, the clamp body is formed with an upward protrusion that engages with the lower surface portion of the seat or the side surface of the guide cylinder to hold the clamp body so that it cannot be swiveled horizontally.
Chair. The upward protrusion of the clamp body is engaged with the lower surface portion of the seat by a posture holding means including a positioning pin and a positioning hole.
The chair according to claim 1. The left and right guide cylinders are formed with cutout holes that expose the front-rear longitudinal portions of the frame material downward, and the clamp body is in contact with the front-rear longitudinal portions exposed from the notch holes from below. ,
The chair according to claim 1 or 2. A receiving plate is fixed to the lower surface of the seat, the guide cylinder is fixed to the receiving plate, and a nut for screwing the screw shaft of the handle is provided, and the handle has a certain range. It is set so that it can be unscrewed only by, and the receiving plate, the guide cylinder, or the clamp body is formed with a posture holding means for holding the clamp body non-rotatably within a range in which the handle can be unscrewed.
The chair according to claim 3.

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