PH12018000048A1

PH12018000048A1 - Chair back curvature adjustment device

Info

Publication number: PH12018000048A1
Application number: PH12018000048A
Authority: PH
Inventors: Chao-Ken Chen
Original assignee: Contract Design And Systems Furniture Specialist Inc
Priority date: 2018-01-19
Filing date: 2018-02-14
Publication date: 2019-09-02

Abstract

The chair back curvature adjustment device includes a flexible chair back, a post, a first holding mechanism, a second holding mechanism and a locking mechanism. The first holding mechanism is connected between a first position of the chair back and the post. The second holding mechanism is connected between a second position of the chair back and the post and has a second connecting portion connected to the second position of the chair back and a second moving portion capable of moving on the post. The locking mechanism is disposed on the second holding mechanism for selectively fixing the second moving portion to the post. The first holding mechanism keeps immovable and the second holding mechanism is movably fixed to the post so as to make the chair back change its curvature.

Description

into one of the tooth holes 3022, the extending portion 301 is positioned to be ~ stopped. Preferably, an end of the positioning bolt 3021 is formed with a - blocking portion 3023 and the other end thereof is formed with a thread 3024 © connecting a handle portion 3025. The handle portion 3025 may be held by a = user to move the positioning bolt 3021 to escape from the tooth holes 3022 so as - to make the extending portion 301 movable again. o

By the movement of the extending portion 301, the second connecting = portion 30 can be retracted or stretched so as to further change the curvature of o the chair back 1. Please refer back to FIG. 5. When the second holding - mechanism 3 is moved to change the curvature of the chair back 1, because the bottom of the chair back 1 is bent more rearward, it may cause insufficient support to some users’ backs. To overcome this problem, the second connecting portion 30 may be extended to reduce the curvature of the chair back 1 as shown in FIG. 8. As a result, sufficient support to users’ backs can be obtained. Of course, besides the second connecting portion, the first connecting portion 20 can also be used to change the curvature of the chair back 1 as abovementioned. 1 chair back 10 first position 11 second position 110 fixing seat 2 first holding mechanism 20 first connecting portion 21 first moving portion 210 guiding rod

211 fixing hole : 3 second holding mechanism - 30 second connecting portion > 300 fixing portion ov 301 extending portion = 302 positioning mechanism o 3020 long hole = 3021 positioning bolt < 3022 tooth hole - 3023 blocking portion 3024 thread 3025 handle portion 31 second moving portion 310 passing hole 32 fixing rod 4 post 40 hollow 41 positioning hole 5 locking mechanism

CHAIR BACK CURVATURE ADJUSTMENT DEVICE ~ : Background of the Invention =

I. Technical Field ’

The invention relates to chairs, particularly to chair backs. i 2. Related Art >

To increase sitting comfort, curvature of chair backs is an absolutely > important factor. When sitting for a long time, users of chairs will feel backache - or users’ vertebrae may be deformed if their backs have no proper support.

Some conventional chairs are provided with an inflatable back capable of changing its curvature to support a user’s back. They can achieve the function, but they are very expensive. Also, their inflation components are embedded in the chair back, so these components are hard to be maintained or repaired.

Furthermore, these components are installed at a fixed position, they can provide support to only one specific position of s user’s back and their extent of deformation is limited, so they are hard to satisfy different requirements of various users.

Summary of the Invention

An object of the invention is to provide a chair back curvature adjustment device, which can offer a large amount of curvature variation.

Another object of the invention is to provide a chair back curvature adjustment device, which is easy to be maintained or repaired.

To accomplish the above objects, the chair back curvature adjustment device of the invention includes a flexible chair back, a post, a first holding mechanism, a second holding mechanism and a locking mechanism. The first = holding mechanism is connected between a first position of the chair back and - the post. The second holding mechanism is connected between a second position = of the chair back and the post and has a second connecting portion connected to = the second position of the chair back and a second moving portion capable of = moving on the post. The locking mechanism is disposed on the second holding o mechanism for selectively fixing the second moving portion to the post. The first = holding mechanism keeps immovable and the second holding mechanism is o movably fixed to the post so as to make the chair back change its curvature. ”

Preferably, the first holding mechanism has a first connecting portion and a first moving portion, the first connecting portion is connected to the first position of the chair back, the first moving portion is slidable against the post, and the locking mechanism is capable of fixing the first moving portion to the post. When the locking mechanism is released, both the first and second moving portions can be adjusted. As a result, either or both of the two moving portions is or are moved, the curvature of the chair back can be adjusted.

Preferably, the second connecting portion comprises a fixing portion connected to the second moving portion, an extending portion connected to the chair back and a positioning mechanism connected between the extending portion and the fixing portion, and the extending portion is movable against the fixing portion and positioned by the positioning mechanism. By the movement of the extending portion, the second connecting portion can be retracted or stretched so as to further change the curvature of the chair back.

Brief Description of the Drawings

FIG. 1 is a perspective view of the invention; =

FIG. 2 is an exploded view of the invention; -

FIG. 3 is an assembled view of the invention; o

FIG. 4 is a schematic view showing the two holding mechanisms in a first cx status; -

FIG. 5 is a schematic view showing the two holding mechanisms in a - second status; =

FIG 6 is a schematic view of the second connecting portion of the = invention; -

FIG. 7 is an exploded view of the second connecting portion of the invention; and

FIG 8 is an operational schematic view of the second connecting portion of the invention.

Detailed Description of the Invention

Please refer to FIGS. 1-3. The chair back curvature adjustment device of the invention includes a flexible chair back 1, a post 4 for supporting the chair back 1, a first holding mechanism 2, a second holding mechanism 3 and a locking mechanism 5. The first holding mechanism 2 is connected between a first position 10 of the chair back 1 and the post 4. The second holding mechanism 3 is connected between a second position 11 of the chair back 1 and the post 4. As a result, the chair back 1 is mounted on the post 4. When the first holding mechanism 2 is fixed, exerting a force onto the second holding mechanism 3 to move on the post 4 can change the second position 11 of the chair back 1 relative to the post 4. Alternatively, when the second holding mechanism 3 is fixed, exerting a force onto the first holding mechanism 2 to ~ move on the post 4 can change the first position 10 of the chair back 1 relative to ~ the post 4. Further alternatively, exerting a force onto both the first holding © mechanism 2 and the second holding mechanism 3 to move on the post 4 - changes both the first position 10 and the second position 11 of the chair back 1 = relative to the post 4. As a result, curvature of the chair back 1 can be changed to o provide comfortable and sufficient support a user’s back. -

The first holding mechanism 2 has a first connecting portion 20 and a first © moving portion 21. The second holding mechanism 3 has a second connecting portion 30 and a second moving portion 31. Preferably, the first connecting portion 20 and the second connecting portion 30 are connected at the top and the bottom of the chair back 1 which is being vertically placed, respectively. The first and second moving portions 21, 31 are separately put around two different positions of the post 4 and can be separately fixed on the post 4 by a locking mechanism 5. The positions of the moving portions 21, 31 can be adjusted after the locking mechanism 5 is released. Accordingly, when either or both of the two moving portions 21, 31 is or are moved, the chair back 1 can be stretched or compressed to make variation of curvature. In other words, the shorter the distance between the two moving portions 21, 31 is, the greater the curvature of the chair back 1 is, which means it can provide hard support. Adversely, the longer the distance between the two moving portions 21, 31 is, the less the curvature of the chair back 1 is, which means it can provide soft support. This is a controllable adjustment. Such an adjustment can provide comfort and satisfy various requirements of users. Particularly, the swollen position can also be controlled by the same operation. In other words, the swell of the chair back 1 may be at a low position to approach a user’s waist. Adversely, the swell of the S chair back 1 may be at a high position to approach a user’s shoulders. ”

Preferably, the post 4 has a hollow 40 and the first moving portion 21 has = a guiding rod 210 whose surface is provided with fixing holes 211 axially i arranged in line. The guiding rod 210 is received in the hollow 40. The - movement of the guiding rod 210 in the hollow 40 makes the first position 10 of - the chair back 1 adjustable. The locking mechanism 5 has a fixing bolt (not = shown). The fixing bolt can pass through the post 4 and one of the fixing holes = 211 to make the first position 10 fixed. -

Preferably, the post 4 is provided with positioning holes 41 axially arranged in line. The second moving portion 31 has a passing hole 310 for allowing the second moving portion 31 to slide on the post 4. The second moving portion 31 is also provided with a locking mechanism 5. As abovementioned, the locking mechanism 5 has a fixing bolt. The fixing bolt can pass through the second moving portion 31 and one of the positioning holes 41 to make the second position 11 fixed. In addition, the second connecting portion 30 is passed by a fixing rod 32. The second position 11 of the chair back 1 is provided with a fixing seat 110 for assembling with the fixing rod 32 so that a removable connection is formed between the second position 11 and the second connecting portion 30. This can simplify repair when damage occurs.

Please refer to FIG. 4. The first position 10 of the chair back 1 can move with the guiding rod 210 and be adjusted on the post 4. At this time, if the second holding mechanism 3 connected to the second position 11 is fixed, then changing the first position 10 can change the curvature of the chair back 1. The locking mechanism 5 can lock this curvature after a user has determined his or = her requirement of curvature. z

Please refer to FIG. 5. Similarly, when the height of the chair back 1 has = been adjusted by the movement of the guiding rod 210, the first position 10 is ” fixed by the locking mechanism, and the second holding mechanism 3 can be I. adjusted to move the second position 11 to change the curvature of the chair i» back 1. Such a change of the curvature is approximately at a position of a lower = back of a user. Finally, the locking mechanism 5 can fix the adjusted curvature.

Of course, if a user wants a maximal stretch or retract of the chair back 1, he or she can adjust both the first and second holding mechanisms 2, 3 against the post 4 to move the first position 2 and the second position 3.

Please refer to FIGS. 6 and 7. The second connecting portion 30 may be composed of a fixing portion 300 connected to the second moving portion 31, an extending portion 301 connected to the chair back 1 and a positioning mechanism 302 connected between the extending portion 301 and the fixing portion 300. The extending portion 301 can be moved against the fixing portion 300 and positioned by the positioning mechanism 302.

The positioning mechanism 302 includes two long holes 3020, each of which is horizontally formed in one of two opposite sides of the fixing portion 300, and a positioning bolt 3021 passing through the extending portion 301. The positioning bolt 3021 also passes through the two long holes 3020 to connect the extending portion 301 with the fixing portion 300. When the extending portion 310 is moved against the fixing portion 300, the positioning bolt 3021 is slid in the long holes 3020. Additionally, a plurality of tooth holes 3022 are formed at a bottom edge of one of the long holes 3020. When the positioning bolt 3021 falls )

Claims

Oe —m—,—m m eee What is claimed is: =

1. A chair back curvature adjustment device comprising: 4 flexible chair back; = a post for supporting the chair back; a first holding mechanism, connected between a first position of the chair = back and the post; i. a second holding mechanism, connected between a second position of the = chair back and the post, having a second connecting portion connected to the o second position of the chair back and a second moving portion capable of - moving on the post; and a locking mechanism, disposed on the second holding mechanism for selectively fixing the second moving portion to the post.

2. The chair back curvature adjustment device of claim 1, wherein the post is provided with positioning holes axially arranged in line, the second moving portion has a passing hole for allowing the second moving portion to slide on the post, the locking mechanism has a fixing bolt, and the fixing bolt passes through the second moving portion and one of the positioning holes to make the second position fixed.

3. The chair back curvature adjustment device of claim 1, wherein the first holding mechanism has a first connecting portion and a first moving portion, the first connecting portion is connected to the first position of the chair back, the first moving portion is ‘slidable against the post, and the locking mechanism is capable of fixing the first moving portion to the post.

4. The chair back curvature adjustment device of claim 3, wherein the post has a hollow, the first moving portion has a guiding rod slidably received in the hollow, and the locking mechanism is capable of fixing the guiding rod to the 2 post. ~

5. The chair back curvature adjustment device of claim 1, wherein the = second connecting portion comprises a fixing portion connected to the second ” moving portion, an extending portion connected to the chair back and a + positioning mechanism connected between the extending portion and the fixing oo portion, and the extending portion is movable against the fixing portion and - positioned by the positioning mechanism. o

6. The chair back curvature adjustment device of claim 5, wherein the positioning mechanism comprises two long holes and a positioning bolt passing through the extending portion, each of the long holes is horizontally formed in one of two opposite sides of the fixing portion, the positioning bolt also passes through the two long holes to connect the extending portion with the fixing portion, and the positioning bolt is slidable in the long holes when the extending portion is moved against the fixing portion.

7. The chair back curvature adjustment device of claim 6, wherein a plurality of tooth holes are formed at a bottom edge of one of the long holes, when the positioning bolt falls into one of the tooth holes, the extending portion is positioned to be stopped, an end of the positioning bolt is formed with a blocking portion, another end of the positioning bolt is formed with a thread connecting a handle portion for moving the positioning bolt to escape from the tooth holes so as to make the extending portion movable.