JPH0444133Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a chair, and particularly to a chair having a locking mechanism that allows the upper part of the backrest to be folded toward the rear of the chair within a predetermined range.

In a conventionally known chair, the backrest portion is fixed to the rear end of the seat plate in a substantially vertically upwardly erected state so as not to move. As a result, when you are sitting in a chair for a long time in a meeting, etc., you stretch your back and arch backwards, and when you try to loosen a lump in your back, improve blood circulation, and relieve fatigue, you force the entire chair backwards and the lower end of your legs. must be rotated around the center, and in such a case,
Some of the legs may come off the floor and become unstable, causing the chair to topple over. Excessive force may be applied to some of the legs of the chair, damaging the legs, or causing damage to the lower ends of the legs. The edges may damage the floor, etc.

In addition, there are conventionally known chairs whose backrests can be bent backwards at an appropriate angle, but all of these chairs have complex structures that make them easily breakable and difficult to handle, and the folding mechanism is not included on the outside of the chair. It has some drawbacks, such as being exposed and looking unsightly, so it has not been put into practical use.

The present invention was developed in view of the above-mentioned conventional problems.The purpose of this invention is to easily tilt only the upper part of the backrest toward the rear of the chair at a predetermined angle while sitting on the chair, allowing the user to straighten their back and arch backwards, thereby improving their backrest. To provide a simple chair that can loosen lumps and has a good appearance without exposing the bending mechanism part of the backrest to the outside of the chair.

In order to achieve this purpose, the frame constituting the framework of the backrest is divided into upper and lower parts approximately in the middle of the backrest, and the backrest part above the divided part is bent backward at a predetermined angle. In the chair, each of the upper ends of both sides of the frame below the divided part is formed into a tapered part that bends toward the rear side of the chair in a substantially dogleg shape, and the frame above the divided part is formed into a tapered part. , a cylindrical body provided at each of the lower end portions on both sides is fitted onto each of the tapered portions and pivoted so as to be rotatable in the front and back direction, and the outer wall surface of the front and rear tapered portions is attached to the upper frame. The chair is formed on a stopper surface that regulates the rotation angle in the front-rear direction, and the chair is provided with a biasing member that biases the upper frame in the upright direction, and the biasing member has both ends connected to the frame. A chair is provided that is loaded along the internal longitudinal direction of the backrest by being locked to locking parts disposed inside the split portion and above and below the divided portion.

Embodiments of the present invention will be described below with reference to the drawings.
1 and 2 show the frame structure of the portion above the seat plate of the chair of the present invention, and the structure of the other leg portions, etc. is the same as that of conventionally known ones, so explanation will be omitted. Omitted. In the figure, reference numeral 10 denotes a seat frame made of a cylindrical pipe provided along the periphery of the bottom plate, and has a substantially U-shape, with end portions 12a and 12b on both sides of the opening of the seat frame 10.
The backrest 1 is bent from the middle and stands up almost perpendicularly above the seat plate 14.
6 It constitutes the lower frame part. Reference numeral 18 denotes a locking frame having a substantially U-shape and provided along the periphery of the upper part of the backrest 16, and is constructed by bending a cylindrical pipe. Furthermore, the lower portions of substantially doglegged locking arms 20a and 20b as shown in FIG. Upper portions 22 of the locking arms each having a tapered peripheral side surface project from each end of the seat frame 10 toward the diagonally upward rear portion of the chair. The tapered locking arm upper part 22 is loosely inserted into the cylindrical space inside both lower end parts of the locking frame 18 at the upper part of the backrest, and the rod-shaped rivet 2
4 is the side wall of the locking frame 18 and the locking arms 20a and 20 inside the locking frame.
The locking frame 18 is connected to the locking bar 20 via a rivet 24, and the lower ends of both sides of the locking frame 18 are connected to the locking bar 20 through rivets 24.
A part of the cylindrical inner wall surface inside the lower ends of both sides of the locking frame 18 comes into contact with the side wall surface of the tapered upper part 22 of the locking arm, centering on the rivet 24 at the midpoint between a and 20b. It is fixed so that it can rotate within a predetermined angular range. Also, 26a
and 26b are a pair of leaf springs having elastic force,
The entire backrest 16 is formed in a substantially dogleg shape following the shape of the above-mentioned rotatable middle part of the backrest 16, and is arranged on both sides of the inside of the bendable middle part of the backrest 16. There is. Frame bars 28 and 30 are respectively installed between the middle parts of the substantially vertical end portions 12a and 12b on both sides of the seat frame 10 and between the middle parts of both sides of the locking frame 18. Both end portions of leaf springs 26a and 26b, which are disposed on both sides inside the backrest 16 between both frame bars, are connected to frame bars 28, respectively.
The leaf spring ends are bent and hooked so as to hold and 30 inside.

In this way, in this embodiment, the frame bar 28
and 30 are reinforcing members for the seat frame 10 and the rocking frame 18, and the leaf spring 26
It is also the locking portion of a and 26b.

Further, a substantially U-shaped locking bar 32 is installed between the lower ends of both sides of the locking bar 18 located halfway between both frame bars, and the locking bar 32 has a midway portion that can be bent in the middle of the backrest 16 described above. It is located along the
Leaf springs 26a arranged on both sides inside the backrest 16
The locking bar 32 supports the bent part in the middle of 26b, and the frame bar 28 installed on the seat frame and the locking bar 32 installed on the locking frame 18 support the backrest 16.
Leaf springs 26a and 26 supported along the inside
b urges the locking frame 18 toward the front of the chair around the rivets 24 on the locking frame 18 via frame bars 30 installed on the locking arms.

Note that the locking bar 32 is preferably disposed on the axis of the rivet 24 to prevent squeaks.

Next, to explain the operating state of the chair with the frame structure constructed above, when you try to stretch your back while sitting on the chair, the backrest 1
6. Against the elastic force of leaf springs 26a and 26b loaded inside, the upper part of the backrest is locked from the middle part around the rivet 24 to the locking frame 18.
At the same time, rotate the locking arms 20a and 20b toward the rear of the chair within a range until the upper side wall surfaces of the locking arms 20a and 20b mounted on the end of the seat frame abut and engage the side wall surface inside the lower end of the locking frame 18 and bend. , stretch your back to improve blood circulation and relieve fatigue. Also, after stretching your back, use the backrest 16.
If you return the back part from the upper part to the front of the chair, the leaf spring 26 loaded inside the backrest will release.
Under the biasing forces of a and 26b, the upper part of the backrest moves toward the front of the chair around the rivet 24, and the upper side wall surfaces of the locking arms 20a and 20b again come into contact with the other side wall parts inside the lower end of the locking frame 18. The chair automatically returns to its rotation within the range until it stops, and stands up substantially perpendicularly above the seat plate portion 14, so that it can be used as a normal chair.
In the above-described embodiment, even if the locking bar 32 that supports the intermediate portions of the leaf springs 26a and 26b is installed not between the locking frames 18 but between the end portions 12a and 12b of the seat frame 10, the above-mentioned effect will still be achieved. It is possible to construct a chair that has the same functions and effects as the chair described above. In addition, the reinforcing frame bars are attached to the seat frame 10 and the rocking frame 1.
The sturdy backrest 16 may be constructed by appropriately installing the plate springs 26 in the vertical and horizontal directions within the 8.
The frame bars 28, 30 and the locking bar 32 that support the middle portions and ends of a and 26b may have a structure in which the middle portions are removed in order to increase the elasticity of the backrest portion. Furthermore, the chair structure according to the present invention can also be used for a chair without legs.

As described above, the chair according to the present invention has a locking mechanism in the upper part of the backrest, and by simply pushing the upper part of the backrest toward the rear of the chair, the upper part of the backrest can be easily bent to an appropriate angle toward the rear of the chair, allowing the user to remain seated on the chair. You can easily stretch your back, relieve the lumps in your back, and relieve fatigue. In addition, in such cases, the chair legs do not leave the floor, so the chair may become unstable and fall over, or unreasonable force may be applied to some of the chair legs, causing the legs or the floor to There is no risk of damaging the surface.

Furthermore, in order to return the upper part of the backrest to its normal state, simply return your back to the front of the chair, and the upper part of the backrest can automatically return to its original state, making handling and operation much easier than conventional ones.

In addition, the folding mechanism is compactly housed within the frame structure of the chair and is not exposed to the outside of the chair at all, which has the effect of not spoiling the appearance of the chair and giving it a good appearance.

Although the present invention has been variously explained above with reference to preferred embodiments, the present invention is not limited to these embodiments, and it goes without saying that many modifications can be made without departing from the spirit of the invention. It is.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the frame structure of a portion above the seat plate of the chair of the present invention, and FIG. 2 is an enlarged side view of the bending mechanism portion of the frame structure of the chair in FIG. DESCRIPTION OF SYMBOLS 10... Seat frame, 12a, 12b... End portion, 14... Seat plate, 16... Backrest, 18...
...Locking frame, 20a, 20b... Locking arm, 22... Upper part of locking arm,
24... Rivet, 26a, 26b... Leaf spring,
28, 30... Frame bar, 32... Locking bar, 34... Block part, 36... Shaft fitting,
38l...first stopper surface, 38m...second stopper surface, 40...stopper, 42...rivet.

Claims (1)

[Claims for Utility Model Registration] The frame constituting the frame, which is the frame structure of the backrest, is divided into upper and lower parts approximately in the middle of the backrest, and the part of the backrest above the divided part can be bent rearward at a predetermined angle. The chair is such that each of the upper ends of both sides of the frame below the divided part is formed into a tapered part that bends toward the rear side of the chair in a substantially dogleg shape, and the frame above the divided part is formed into a tapered part. A cylindrical body provided at each of the lower end portions on both sides is fitted onto each of the tapered portions and pivoted so as to be rotatable in the front-rear direction, and the outer wall surface of the tapered portion is attached to the front and back of the upper frame. The chair is formed on a stopper surface that regulates the rotation angle in the direction, and the chair is provided with a biasing member that biases the upper frame in the upright direction, and the biasing member is
The device is characterized in that its both ends are locked to locking portions located inside the frame and above and below the split portion, and loaded along the internal longitudinal direction of the backrest. Chair.