BACKREST OF HEIGHT-ADJUSTABLE CHAIR

Abstract

A backrest of a height-adjustable chair includes a height-adjustable seat including a seat cushion frame, a seat cushion thereon, and a backrest connection unit including a first mounting portion and a second mounting portion on the seat cushion frame; and a backrest body including a backrest frame body, a backrest plate, and an S-shaped frame body therebetween. A clearance for adjustment is defined between the backrest frame body and the backrest plate, and an S-shaped portion of the S-shaped frame body is located therein. An end of the backrest frame body close to the height-adjustable seat is mounted at the first mounting portion, a lower end of the S-shaped frame body is mounted at the second mounting portion, when the backrest body is raised, the S-shaped frame body is extended, and when the backrest body is lowered, the S-shaped frame body is compressed.

Claims

1. A backrest of a height-adjustable chair, comprising: a height-adjustable seat comprising a seat cushion frame, a seat cushion on the seat cushion frame, and a backrest connection unit on the seat cushion frame, wherein the backrest connection unit comprises a first mounting portion and a second mounting portion; and a backrest body comprising a backrest frame body, a backrest plate connected to a part of the backrest frame body, and an S-shaped frame body between the backrest frame body and the backrest plate, wherein a clearance for adjustment is defined between the backrest frame body and the backrest plate, and an S-shaped portion of the S-shaped frame body is located in the clearance for adjustment; wherein an end of the backrest frame body close to the height-adjustable seat is mounted at the first mounting portion, a lower end of the S-shaped frame body close to the height-adjustable seat is mounted at the second mounting portion, when the backrest body is raised, the S-shaped frame body is extended, and when the backrest body is lowered, the S-shaped frame body is compressed.

2. The backrest of the height-adjustable chair according to claim 1, wherein the backrest frame body is a frame body with a space in a middle of the backrest frame body, a cam is provided between the backrest frame body and the S-shaped frame body, and a connecting lug for mounting the cam is provided on the backrest frame body; wherein an end of the backrest plate close to the height-adjustable seat is provided with a mounting lug, a cam hole is defined in the mounting lug, and when the backrest plate is assembled with the backrest frame body, the cam is located in the cam hole.

3. The backrest of the height-adjustable chair according to claim 2, wherein the S-shaped frame body comprises a first curved portion and a second curved portion, the second curved portion is located close to the height-adjustable seat, the first curved portion is connected to the second curved portion and the first curved portion is located above the second curved portion, the first curved portion and the second curved portion are curved away from each other, and a lower half of the backrest plate aligns flush with the first curved portion.

4. The backrest of the height-adjustable chair according to claim 3, wherein textures are uniformly provided on the backrest plate, the textures are configured to ensure comfort after the backrest plate is bent, an upper half of the backrest plate is defined as a first backrest plate while the lower half of the backrest plate is defined as a second backrest plate, and a thickness of the first backrest plate is smaller than a thickness of the second backrest plate.

5. The backrest of the height-adjustable chair according to claim 3, wherein the first curved portion has a curvature, and the second curved portion is uniformly configured with a plurality of cushioning grooves on a surface facing the height-adjustable seat.

6. The backrest of the height-adjustable chair according to claim 5, wherein the plurality of cushioning grooves are L-shaped.

7. The backrest of the height-adjustable chair according to claim 6, wherein the backrest connection unit is L-shaped, the first mounting portion extends horizontally while the second mounting portion extends vertically, the first mounting portion is connected to the seat cushion frame, and a chamber around the second mounting portion is defined at a bottom of the backrest frame body, so that the backrest frame body is adjustable in a vertical direction.

8. The backrest of the height-adjustable chair according to claim 7, wherein a height positioning structure is provided between the backrest frame body and the backrest connection unit, and the height positioning structure is configured to lock a height position of the backrest.

9. The backrest of the height-adjustable chair according to claim 7, wherein a lug plate is provided at the lower end of the S-shaped frame body, the lug plate is configured with a connecting hole, and the S-shaped frame body is rotatably connected to the first mounting portion via the connecting hole.

10. The backrest of the height-adjustable chair according to claim 9, wherein the S-shaped frame body is rotatably connected to a rear end of the seat cushion frame via the connecting hole.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG. 1 is an overall schematic structural diagram showing a backrest of a height-adjustable chair according to an embodiment of the present application;

[0029] FIG. 2 is a schematic side view showing the backrest of the height-adjustable chair; and

[0030] FIG. 3 is a schematic structural diagram showing a backrest body.

DETAILED DESCRIPTION

[0031] This application is described in further detail below with reference to FIGS. 1-3.

[0032] Disclosed in the embodiments of the present application is a backrest of a height-adjustable chair. Referring to FIGS. 1 and 2, the backrest of the height-adjustable chair includes a height-adjustable seat 1 and a backrest body 2. The height-adjustable seat includes a seat cushion frame 11, a seat cushion 12 on the seat cushion frame 11, and a backrest connection unit 13 on the seat cushion frame 11. The backrest connection unit 13 includes a first mounting portion and a second mounting portion for mounting a backrest body 2. The backrest body 2 includes a backrest frame body 21, a backrest plate 22 connected to a part of the backrest frame body 21, and an S-shaped frame body 23 between the backrest frame body 21 and the backrest plate 22. A clearance for adjustment 24 is present between the backrest frame body 21 and the backrest plate 22, and an S-shaped portion of the S-shaped frame body 23 is located in the clearance for adjustment 24.

[0033] The backrest connection unit 13 is L-shaped, where the first mounting portion extends horizontally while the second mounting portion extends vertically, and the first mounting portion is connected to the seat cushion frame 11. A chamber around the second mounting portion is defined at a bottom of the backrest frame body 21, so that the backrest frame body 21 can be vertically adjusted. The chamber provides a bending space for the S-shaped frame body 23 when adjusting the height of the backrest, which prolongs the life of the seat.

[0034] One end of the backrest frame body 21 close to the height-adjustable seat 1 is mounted at the first mounting portion, and one end of the S-shaped frame body 23 close to the height-adjustable seat is mounted at the second mounting portion. When the backrest body 2 is raised, the S-shaped frame body 23 is extended, and when the backrest body 2 is lowered, the S-shaped frame body 23 is compressed. When the backrest is raised, the S-shaped frame body is elongated and deformed in a height direction. Since the S-shape may be elastically deformed starker, and the S-shape may be elastically deformed in the vertical direction, the backrest is short when the backrest body 2 is lowered, and backrest is long when the backrest body 2 is raised, that is, the shape of the backrest changes with the height. The backrest is more flexible in use by the S-shaped design thereof, while ensuring the visual integrity of the backrest.

[0035] The backrest frame body 21 is a frame body with a space in the middle, a cam 211 is provided between the backrest frame body 21 and the S-shaped frame body 23, and a connecting lug for mounting the cam 211 is provided on the backrest frame body 21. One end of the backrest plate 22 close to the height-adjustable seat is provided with a mounting lug, a cam hole is formed in the mounting lug. When the backrest plate 22 is assembled with the backrest frame body 21, the cam 211 is located in the cam hole. There is a space in the middle of the backrest frame body 21 for a first purpose that the weight of the backrest frame body 21 can be reduced while ensuring the strength, and for a second purpose that the material can be saved so as to reduce the cost while ensuring the overall strength. After the backrest plate 22 is connected with the backrest frame body 21, the shape of the backrest plate 22 changes along with the S-shaped frame body 23, after the user adjusts the height, which not only ensures the integrity but also realizes that the backrest plate 22 changes along with the S-shaped frame body 23 to form an arc-shaped protrusion, which functions as a back cushion when one leans against the backrest, so that the user does not need to use a back cushion, thereby avoiding the trouble of dropping the back cushion.

[0036] In an optional embodiment, the S-shaped frame body 23 includes a first curved portion 231 and a second curved portion 232, where the second curved portion 232 is close to the height-adjustable seat, the first curved portion 231 is connected to the second curved portion 232 and the first curved portion 231 is located above the second curved portion 232, the first curved portion 231 and the second curved portion 232 are curved away from each other, and a lower half of the backrest plate 22 aligns flush with the first curved portion 231. A lower part of the backrest plate 22 aligns flush with the first curved portion 231 and forms a protruding arc-shaped profile along with the first curved portion, which not only ensures an integrated visual effect but also improves comfort. During use, it supports the user's back. When adjusting the height of the backrest, the position and curvature of the first curved portion 231 will also vary, allowing it to accommodate users of different heights during the lifting process.

[0037] In an optional embodiment, the backrest plate 22 is uniformly provided with textures 224, the textures 224 ensure comfort after the backrest plate 22 is bent. An upper part of the backrest plate 22 is a first backrest plate 221, a lower part of the backrest plate 22 is a second backrest plate 222, and the thickness of the first backrest plate 221 is smaller than that of the second backrest plate 222. The texture 224 on the backrest plate 22 is of a special shape, the textures 224 reduce discomfort after the backrest plate 22 is bent and improve the comfort of the waist and the back. The thickness of the first backrest plate 221 is smaller than that of the second backrest plate 222 so that the first backrest plate 221 fits and wraps the back more comfortably, and the second backrest plate 222 can support the waist and conforms to ergonomics.

[0038] The first curved portion 231 has a curvature, and the second curved portion 232 is uniformly configured with a plurality of cushioning grooves 233 on a surface thereof facing the height-adjustable seat. The curvature of the first curved portion 231 mainly configured for supporting, and the cushioning grooves 233 are mainly provided to increase the clearance for adjustment 24, so that the second curved portion 232 can achieve a better bending degree while reducing stress. In an optional embodiment, the cushioning groove 233 is L-shaped. The specially shaped groove increases deformation of the second curved portion 232.

[0039] A lug plate is provided at a lower end of the S-shaped frame body 23, the lug plate is configured with a connecting hole 234, and the S-shaped frame body 23 is rotatably connected to the first mounting portion via the connecting hole 234. Optionally, the S-shaped frame body 23 is rotatably connected to a rear end of the seat cushion frame 11 via the connecting hole 234. The lower end of the S-shaped frame body 23 is rotatably connected to the rear end of the seat cushion frame 11 or the backrest connection unit 13, so as to better conform to the elongation and deformation of the S-shaped frame body 23, making backrest adjustment more effortless. Additionally, while meeting the requirement for large deformation, the diameter of the second curved portion 232 of the S-shaped frame body 23 can be designed smaller, so as to occupy less space, thus enhancing aesthetic appeal.

[0040] In an optional embodiment, the S-shaped frame body 23 is made of a super-tough nylon material. In an optional embodiment, the outer surface of the S-shaped frame body 23 is entirely wrapped with the material. Apparently, the backrest provides a smooth visual transition during height adjustment, which eliminates visual disruption in conventional designs, is more aesthetically pleasing, and the back cushion, which is additionally placed by the user, is not easily be clamped between the backrest and the seat cushion 12.

[0041] Optionally, a height positioning structure is provided between the backrest frame body 21 and the backrest connection unit 13, and the height positioning structure can lock the height position of the backrest, which can prevent the unlocked backrest from changing its height, which leads to is inconvenience. The height positioning structure includes a rack on the backrest connection unit 13, a first redirection structure at an upper end of the rack, and a second redirection structure at a lower end of the rack. Spring-loaded locking teeth are provided on the backrest frame body 21, which cooperate with the rack for locking.

[0042] When the user pulls the backrest frame body 21 upwards, the spring-loaded locking teeth can move upwards along the rack, and when the upward pulling is stopped, the spring-loaded locking teeth can be meshed with the rack under the action of the spring to be locked in the current position. When the spring-loaded locking teeth are aligned with the upper end of the rack, the spring-loaded locking teeth may contact the first redirection structure, thereby maintaining the spring-loaded locking teeth in a retracted state, at which time the backrest frame body 21 can be lowered smoothly. When the backrest frame body is lowered to the lower end of the rack, the spring-loaded locking teeth contact the second redirection structure, so that the spring-loaded locking teeth deploys from the retracted state, so as to be meshed and locked with the rack. Since the spring-loaded locking teeth are in the retracted state when the backrest body 2 is released at the uppermost position, the backrest body 2 may falling directly down, and the S-shaped frame body 23 may buffer the movement of such a direct falling movement, thereby preventing the impact sound caused by the direct dropping of the backrest body 2, and even hitting a person.

[0043] The implementation principle of the embodiments of the present application is as follows. When the backrest is raised, the S-shape is elongated and deformed in the height direction. Since the S-shape may be starker elastically deformed, and the S-shape is elastically deformed in the vertical direction, the backrest is a short backrest shape when the backrest body 2 is lowered, and is a long backrest shape when the backrest body 2 is raised, and the shape changes with the height, so that the backrest is more flexible in use by the S-shape and the visual integrity of the backrest is ensured. There is a space in the middle of the backrest frame body 21 for a first purpose that the weight of the backrest frame body 21 can be reduced while ensuring the strength, and for a second purpose that the material can be saved so as to reduce the cost while ensuring the overall strength. After the backrest plate 22 is connected with the backrest frame, the shape of the backrest plate 22 changes along with the S-shaped frame body 23, after the user adjusts the height, which not only ensures the integrity but also realizes that the backrest plate 22 changes along with the S-shaped frame body 23 to form an arc-shaped protrusion, which functions as a back cushion when one leans against the backrest, so that the user does not need to use a back cushion, thereby avoiding the trouble of dropping the back cushion.

[0044] The above-mentioned optional embodiments of the present application do not limit the scope of protection of the present application, and therefore: all changes which come within the meaning and range of equivalence of the claims are to be embraced within their scope.

LIST OF REFERENCE NUMERALS

[0045] 1 height-adjustable seat [0046] 11 seat cushion frame [0047] 12 seat cushion [0048] 13 backrest connection unit [0049] 2 backrest body [0050] 21 backrest frame body [0051] 211 cam [0052] 22 backrest plate [0053] 221 first backrest plate [0054] 222 second backrest plate [0055] 223 cam hole [0056] 224 texture [0057] 23 S-shaped frame body [0058] 231 first curved portion [0059] 232 second curved portion [0060] 233 cushioning groove [0061] 234 connecting hole [0062] 24 clearance for adjustment