JPH049864Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a chair back tilting device, and more particularly to a backrest tilting device that has a simple structure and can tilt a two-step folding backrest.

[Conventional technology]

Conventionally, as a two-step folding backrest tilting device for a chair, two sets of connecting members having a structure in which a shaft is fitted inside a spring body are connected in opposite directions as disclosed in Japanese Patent Publication No. 7803/1983. However, there are structures in which the tips of both shafts are connected to the upper backrest and the main body, respectively.

[Problem that the invention attempts to solve]

However, such a backrest tilting device has a structure in which the backrest is elastically supported by transmitting the elastic force of the spring body to the connecting part via the shaft, so the structure of the movable part is complicated and the number of parts is large, resulting in the tilting. In addition to being prone to defects, the manufacturing process is complicated, and in the case of a double-folding backrest, a tilting device is required for each bending portion.

In view of the above-mentioned problems, the present invention is a chair back tilting device that can be easily attached to a chair, has a simple movable part structure, is less likely to cause tilting defects, and reduces the number of parts and streamlines the manufacturing process. It is an object of the present invention to provide a chair back tilting device which is not only simple but also has a simpler structure by allowing a single tilting device to tilt a two-stage folding backrest.

[Means for solving problems]

In order to achieve the above object, the present invention has a shape that can be attached to the upper backrest frame for attaching the upper backrest plate, and extends from the lower end through the neck part to a disc-shaped engagement part having a larger diameter than the neck part. An upper connecting part formed in series;
a lower connecting portion having a shape that can be attached to the lower backrest frame and connecting a disc-shaped engaging portion having a diameter larger than the neck from the upper end via the neck; and the upper and lower connecting portions penetrating the inside in the vertical direction. an annular protrusion protruding from the inner circumferential wall of the upper and lower openings of the inner space so that the engaging parts of the upper and lower connecting parts can be engaged with each other at a distance from each other; The connecting rods are connected by engaging the engaging portions of the upper and lower connecting portions with the upper and lower annular projections of the connecting rod, and the elastic member is press-fitted into the internal space between the spaced apart engaging portions of the upper and lower connecting portions. to form a connecting member by elastically biasing the engaging portion of the upper and lower connecting portions to the upper and lower annular protrusions of the connecting rod, and attaching an upper back frame to which a backrest plate is attached to the upper connecting portion of the connecting member; It is an object of the present invention to provide a chair back tilting device characterized in that a lower connecting portion is attached to a lower back frame.

[Effect]

The chair back tilting device according to the present invention has the above-mentioned configuration, and when a person sits on the chair and a load is applied to the backrest, the upper and lower backrest frames connected by the connecting member move at the upper and lower connecting parts. The upper and lower engaging parts, which are engaged with the upper and lower annular protrusions of the connecting rods of the upper and lower connecting parts and are elastically biased by the elastic member, tilt against the elastic force of the elastic member and press the elastic member from above and below. By bending while bending, the backrest of the chair bends elastically at two points, between the lower back frame and the connecting rod and between the connecting rod and the upper back frame, causing the chair back to bend in two steps and tilt. When the load of the seated person is removed, the engaging portion of the upper and lower connecting portions of the connecting member is elastically biased toward the upper and lower annular projections of the connecting rod by the elastic force of the elastic member, returning to its original state, and the back of the chair is restored. The candle returns to its original position.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to embodiments shown in the drawings.

A chair 1 equipped with a chair back tilting device according to the present invention is constructed by, for example, as shown in FIG. A lower back frame 4 is extended upward from the rear end of the frame 2, and two sets of frames each having a rear supporting leg 5 are arranged opposite to each other on the lower back frame 4, and a seat is provided between both horizontal frames 2, 2. 6 is constructed to constitute the chair body 7, and both lower back frames 4,
Both lower ends of an upper back frame 11, which has an upper back frame 10 attached to the inside of a substantially inverted U-shape, are connected via middle back frames 9, 9 to which a lower back frame 8 is attached to the upper end of 4. , a bending part cover made of synthetic resin or the like in a bellows shape at the connecting portion between the lower back frame 4, 4 and the middle back frame 9, 9, and between the middle back frame 9, 9 and both ends of the upper back frame 11; 12 and 13.

The structure of the above-mentioned chair back tilting device includes a lower back frame 4 upper end opening and an upper back frame 1.
1. A disk-shaped engagement having a shape that can be installed in a lower end opening in a substantially tight-fitting state, and having a diameter larger than the necks 14, 15 and a curved peripheral edge from the end through cylindrical necks 14, 15. The upper and lower connecting parts 18 and 19 formed by connecting the parts 16 and 17 and the upper and lower backrest frames 11 and 4 are connected inside the tubular middle backrest frame 9. The upper and lower annular protrusions 21 and 22 are provided on the inner circumferential walls of the upper and lower openings of the through hole, which is a tube body that has a shape that can be fitted in a substantially tight fit state to the middle back frame 9 and has approximately the same length as the middle back frame 9. The engaging portions 16 and 17 of the upper and lower connecting portions 18 and 19 are provided in a protruding manner.
A connecting rod 2 having a structure that allows the two to be engaged with each other while being separated from each other.
0 and the engaging parts 16 and 1 of the upper and lower connecting parts 18 and 19
7 are engaged with and connected to the upper and lower annular protrusions 21 and 22 of the connecting rod 20, and a spring 23 as an elastic member is press-fitted between both the upper and lower engaging parts 16 and 17, and the spring 23 engages the upper and lower annular protrusions 21 and 22. The connecting rod 20 is elastically biased at the upper and lower ends of the spring 23 so that the entire circumferential edges of the engaging portions 16 and 17 are in contact with the upper and lower annular protrusions 21 and 22 of the connecting rod 20, respectively. A connecting member 24 is constructed by connecting the upper and lower connecting parts 18 and 19 in a linear direction on the upper and lower sides of the connecting rod 20.
The upper connecting part 18 of the connecting member 24, which is fitted into the middle back frame 9 and fixed by screwing or caulking, is connected to the neck from the lower end opening of the upper back frame 11 to which the upper back frame 10 is attached. 14 in the protruding state and fix it with screws or caulking, etc., and connect the lower connecting part 19 of the connecting member 24 from the upper end opening of the lower back frame 4 to the neck part 1.
5 is inserted into the protruding state and fixed with screws or caulking, etc., thereby bending the lower back frame 4, the middle back frame 9, and the upper back frame 11 elastically at their respective connecting parts. It is possible to connect them.

When a person sits on the chair 1 equipped with the chair back tilting device as described above and a load is applied to the upper backrest plate 10 and the lower backrest plate 8, both the backrest plates 10 and 8 are attached. The connecting portion between the upper back frame 11 and the middle back frame 9 and the connecting portion between the middle back frame 9 and the lower back frame 4 are connected to the upper and lower annular protrusions 21 and 22 of the connecting rod 20 by the elastic force of the spring 23.
The disc-shaped engaging parts 16 and 17 of the upper connecting part 18 and the lower connecting part 19, which are elastically biased and in contact with each other, are inclined with a part of the peripheral edge as a fulcrum, and the upper and lower annular protrusions 2
Spring 2 forms an inclination angle with 1 and 22.
3 is bent while being pressed from above and below against its elastic force. Next, when the load of the person sitting on the chair 1 is removed, the engaging parts 16 and 17 of the upper and lower connecting parts 18 and 19
are elastically biased by the elastic force of the spring 23 so that their entire circumferential edges come into contact with the upper and lower annular protrusions 21 and 22 of the connecting rod 20, respectively, and the upper back frame 11, the middle back frame 9, and the lower back frame 4 The upper backrest plate 10 and the lower backrest plate 8 return to their original positions.

According to the chair back tilting device as described above, the backrest is connected to the upper and lower connecting parts 18 and 1 connected to the connecting member 24.
9 into the end openings of the upper and lower backrest frames 11 and 4, respectively, and fix them.
Since it has a simple structure in which the disc-shaped engaging parts 16 and 17 are elastically biased to the upper and lower annular protrusions 21 and 22 at the upper and lower ends of the If the shape of the plate-like engaging parts 16 and 17 is formed so that the peripheral edge part is curved as described above, the annular protrusion 2
1 and 22, thereby preventing the occurrence of abnormal noises, etc., and the two-step folding structure at the upper and lower connecting parts is tilted while supporting the backrest elastically by the biasing force of one spring 23. Since this is possible, the number of parts is small and the manufacturing process can be simplified.

Incidentally, the chair back tilting device according to the present invention is not limited to the above-mentioned embodiment. For example, as shown in FIG. If the spherical members 25 and 26 such as The tilting motion of the can also be made smooth and good. In addition, as shown in FIG.
By forming the recesses 27 and 28 as receiving portions, the transmission relationship between the engaging portions 16 and 17 and the spring 23 is further smoothed, and the bending movement at the connection portion of the backrest frame is made smoother. It can be done. In addition, if the connecting rod 20 is structured to connect two pipe bodies 20' and 20'' by screwing together as shown in FIG. 6, the length of the connecting rod 20 can be adjusted and the backrest can be adjusted. It is also possible to adjust the amount of tilting of the backrest by adjusting the height of the plate and increasing or decreasing the elastic force exerted by the spring 23 on the upper and lower engaging portions 16 and 17.Furthermore, in the above embodiment, , a connecting rod 20 between the upper backrest plate 10 and the connecting member 24
The lower backrest plate 8 is attached to the middle backrest frame 9 to form a two-stage folding backrest chair with upper and lower halves, but the lower backrest plate 8 does not necessarily need to be attached, and the connecting member 24 is Upper and lower connecting parts 18,1
Since they can be connected at 9, the chair back can be made into a multi-stage folding structure by sequentially connecting them to form a back frame.

[Effect of idea]

As described above, the chair back tilting device according to the present invention has a shape that can be attached to the upper back frame for attaching the upper back plate, and extends from the lower end through the neck to a disc-shaped body having a larger diameter than the neck. An upper connecting part formed by connecting engaging parts, and a lower connecting part formed by connecting a disc-shaped engaging part with a diameter larger than the neck from the upper end via the neck, which has a shape that can be attached to the lower backrest frame. and an internal space having a shape that penetrates in the vertical direction and into which the engaging part of the upper and lower connecting parts can be inserted, and the engaging part of the upper and lower connecting parts is attached to the inner circumferential wall of the upper and lower openings of the internal space. Connecting rods each having annular protrusions that can be engaged at a distance from each other are connected by engaging the engaging portions of the upper and lower connecting portions with the upper and lower annular protrusions of the connecting rod, and the upper and lower connecting portions are separated. The connecting member is constituted by press-fitting an elastic member into the internal space between the engaged parts and elastically biasing the engaging part of the upper and lower connecting parts to the upper and lower annular protrusions of the connecting rod, and the upper connecting part of the connecting member It is characterized by an upper back frame with a backrest plate attached, and a lower connecting part attached to the lower back frame.It can be easily attached to a chair, and the structure of the movable parts is simple, preventing tilting defects. This not only simplifies the manufacturing process by reducing the number of parts, but also allows for a simpler structure by allowing the two-fold folding backrest to be tilted with a single tilting device, and by using multiple connecting members, the backrest can be simplified. It is possible to provide a chair back tilting device that can make the backrest have a multi-stage folding structure.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an example of a chair equipped with a chair back tilting device according to the present invention, FIG. 2 is a partial sectional view showing essential parts of the chair back tilting device, and FIG.
FIG. 4 is a partial sectional view of the main part showing the tilting state of the tilting device of the chair, FIG. 4 is a partial sectional view of the main part showing another embodiment, FIG. 5 is a partial sectional view of the main part of another embodiment, and FIG. FIG. 6 is a partial sectional view of a main part of an embodiment in which the connecting rod of the chair back tilting device according to the present invention is extendable and retractable. 1... Chair, 2... Lateral frame, 3... Front supporting leg, 4... Lower back frame, 5... Rear supporting leg, 6...
...Seat, 7...Chair body, 8...Lower backrest plate, 9
...Middle back seat frame, 10...Upper back seat plate, 11
... Upper back frame, 12 ... Bent part cover, 1
3... Bent part cover, 14... Neck part, 15... Neck part, 16... Engagement part, 17... Engagement part, 18...
Upper connecting part, 19... Lower connecting part, 20... Connecting rod, 21... Annular protrusion, 22... Annular protruding part, 23
... Spring, 24 ... Connection member, 25 ... Spherical member, 26 ... Spherical member, 28 ... Recess, 29
...Concavity.

Claims (1)

[Scope of utility model registration request] an upper connecting part having a shape that can be attached to the upper back frame for attaching the upper backrest plate and having a disc-shaped engaging part connected from the lower end through the neck and having a diameter larger than the neck, and the lower back; A lower connecting part has a shape that can be attached to the canopy frame and connects a disc-shaped engaging part with a larger diameter than the neck from the upper end via the neck, and a lower connecting part that penetrates the inside in the vertical direction and engages the upper and lower connecting parts. It has an internal space having a shape that allows the fitting part to be inserted therein, and an annular protrusion protruding from the inner circumferential wall of the upper and lower openings of the internal space so that the engaging parts of the upper and lower connecting parts can be engaged with each other at a distance from each other. The upper and lower connecting rods are connected by engaging the engaging portions of the upper and lower connecting portions with the upper and lower annular protrusions of the connecting rods, and press-fitting an elastic member into the internal space between the spaced apart engaging portions of the upper and lower connecting portions to connect the upper and lower connecting rods. A connecting member is constructed by elastically biasing the engaging portion of the connecting portion to the upper and lower annular protrusions of the connecting rod, and an upper back frame with a backrest plate attached is attached to the upper connecting portion of the connecting member, and the lower portion is connected. A chair back tilting device characterized in that a lower backrest frame is attached to a lower backrest frame.