CN114098335B

CN114098335B - Chair

Info

Publication number: CN114098335B
Application number: CN202111361512.7A
Authority: CN
Inventors: 陈琼
Original assignee: Anji Hexuan Home Furnishings Co ltd
Current assignee: Anji Hexuan Home Furnishings Co ltd
Priority date: 2021-11-17
Filing date: 2021-11-17
Publication date: 2024-01-19
Anticipated expiration: 2041-11-17
Also published as: CN114098335A

Abstract

The invention discloses a chair, which comprises two chair frames, a chair surface layer, a chair foot rest and a base, wherein the two chair frames are arranged at intervals left and right; the two chair frames are provided with adjusting seats which are movably connected with the base; when the load of the seat layer is stressed, the adjusting seat drives the seat frame to move relative to the base, so as to buffer the rapid increase of the tension of the seat layer. The invention has the beneficial effects that the chair surface layer can be better protected.

Description

Chair

Technical Field

The present invention relates to a chair.

Background

The cost of the chair manufacturing industry comprises material cost, labor cost, manufacturing cost and transportation cost, wherein one very important factor influencing the transportation cost is the cabinet loading amount of the chair, and the space occupied by the detachable chair before assembly is inversely proportional to the cabinet loading amount, so that the volume compression ratio is an important means for saving the transportation cost when the chair is packaged.

For example, patent application publication number CN204336339U discloses a folding chair comprising a back, a seat, a connecting member and a locking member, the back and the seat being rotatably connected by the connecting member, the back and the seat being rotatable about the connecting member between a first position in which the back is substantially in an upright position and a second position in which the back is folded to lie against the seat, the locking member comprising a first portion and a second portion, the first portion being located on the back and the second portion being located on the seat, the first portion and the second portion of the locking member being engaged and the back being movable relative to the seat in the direction of its axis of rotation to lock or disengage the first portion and the second portion, thereby preventing or allowing relative rotation of the back and seat. The chair has the advantages that the components of the connecting piece and the locking piece for realizing the folding function of the chair back are more, and the structure is relatively complex. The folding and storing functions are mainly applied to the transportation process, and the probability of use is low in actual use, so that the cost on the functions is low in cost performance.

For example, patent application publication number CN201346027 discloses a simple detachable and foldable chair, especially a chair structure with foldable legs, without tools. The chair comprises a chair backup plate, a chair seat plate, a left chair leg frame and a right chair leg frame, wherein plugs are symmetrically fixed on the left side and the right side of the chair backup plate; the head of the chair leg frame is respectively provided with a cannula, and the plug can be tightly inserted into the cannula; the chair leg frames are respectively provided with a cross arm, and the chair seat board is movably connected with the cross arms. The folding chair structure can realize the folding function of the chair through simple plug-in action, does not need any tool, and can conveniently fold the backrest and the seat frame of the chair, thereby reducing the space occupation and saving the storage and transportation cost. Although the chair can preferably reduce space occupation, the chair requires too many parts to be assembled, which is troublesome for users to assemble, especially users with poor handling ability.

In addition, to the chair that the office was used, the user was longer when sitting, and the permeability requirement on user's buttock and back is higher, for example the patent application of publication number CN201509912U, discloses a net chair, and it includes from the bottom and go up chair leg, chair frame, seat support and the back of the chair that sets gradually, the seat support includes chair seat frame and screen cloth, and the screen cloth is tightened and is installed in chair seat frame upper edge, and the back of the chair includes back of the chair frame and screen cloth, and the screen cloth is tightened and is installed in the week of back of the chair frame along, and the both sides fretwork shaping of chair seat frame has the bracing piece of crisscross setting. The mesh cloth has the characteristics of good air permeability and good elasticity, people sit on the mesh chair and lean on the mesh chair, and the mesh cloth deforms along with the weight of the buttocks and the back of the human body, so that the use is comfortable; after the cleaning device is used for a certain time, the mesh can be cleaned only by brushing the cleaning tool on the mesh, and the cleaning is convenient; the support rods which are formed by hollowing out the two sides of the seat frame and are arranged in a staggered mode can increase the supporting force of the seat frame on one hand, so that the stress range of the seat frame is larger, and the weight of the seat frame can be reduced on the other hand, so that the weight of the net chair is lighter. According to the chair, the mesh is in a tight state, so that the tension of the mesh can be increased when a user sits down, the tension of the mesh is reduced after long-time use, the mesh is loose locally, and the joint of the edge of the mesh and the chair seat is broken.

Disclosure of Invention

The invention aims to provide a chair which can play a better role in protecting a chair surface layer.

The invention is realized by the following technical scheme.

A chair comprises two chair frames which are arranged at intervals left and right, a chair surface layer which is fixed by the two chair frames and is unfolded left and right, a chair foot rest and a base which is connected with the chair foot rest; the two chair frames are provided with adjusting seats which are movably connected with the base; when the load of the seat layer is stressed, the adjusting seat drives the seat frame to move relative to the base, so as to buffer the rapid increase of the tension of the seat layer.

As a further improvement of the invention, the two adjusting seats are respectively connected with the left end and the right end of the base in a rotating way, and the rotating axes of the two adjusting seats extend along the front-back direction; the two adjusting seats can rotate in opposite directions to change the left-right distance between the two chair frames, and rotate in the same direction to change the left-right inclination amplitude of the two chair surface layers.

As a further improvement of the invention, the base and the adjusting seat are respectively provided with a first limit structure and a second limit structure which can be blocked mutually, and the first limit structure and the second limit structure are used for limiting the maximum angle of the adjusting seat which is turned downwards relative to the base and limiting the maximum threshold value of the left-right spacing between the two chair frames.

As a further improvement of the invention, a first elastic reset piece is arranged between the base and the adjusting seat and is used for driving the adjusting seat to rotate and reset.

As a further improvement of the invention, at least one supporting frame is arranged between the two chair frames, and the left end and the right end of the supporting frame are respectively connected with the corresponding chair frames; and the supporting frames always apply supporting force for resisting the continuous reduction of the left-right spacing to the two chair frames in the process that the left-right spacing of the two chair frames is gradually reduced by the maximum threshold value.

As a further improvement of the present invention, the chair frame includes a chair seat frame extending substantially back and forth, and a chair back frame extending substantially up and down; the seat surface layer comprises a seat surface layer fixed by two seat frames and stretched left and right, and a seat back surface layer fixed by two seat back frames and stretched left and right.

As a further development of the invention, the support frame is arranged between the front parts of the two seat frames and between the upper parts of the two back frames in front of the adjusting seat.

As a further improvement of the invention, a waist support is arranged between the two chair back frames at the position corresponding to the waist of the user, and the left end and the right end of the waist support are respectively connected with the corresponding chair back frames and can support the surface layer of the chair back.

As a further improvement of the present invention, the base is rotatably connected to the top end of the chair leg, and the rotation axis thereof extends in the left-right direction.

As a further improvement of the invention, a second elastic reset piece is arranged between the base and the top end of the chair leg frame and is used for driving the base to rotate and reset.

The invention has the beneficial effects that:

according to the invention, through the rotary connection of the adjusting seat and the base, the buffer effect of the rapid increase of the tension degree when the load of the seat surface layer is pressed is realized, the irreversible stretching deformation of the seat surface layer can be avoided, and the connection between the edge of the seat surface layer and the seat frame can be prevented from being damaged; in addition, the chair can provide the left and right leisure function.

Drawings

Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings, to facilitate understanding of the objects and advantages of the present invention, wherein:

FIG. 1 is a schematic view of a chair;

FIG. 2 is a schematic view of the chair with the seat removed;

FIG. 3 is a schematic view of the structure of the chair frame;

FIG. 4 is an exploded view of the chair frame;

FIG. 5 is a schematic structural view of a skeleton;

FIG. 6 is a schematic view of the structure of the adapter;

FIG. 7 is a schematic view of a base structure;

FIG. 8 is an exploded view of the base unit;

FIG. 9 is a schematic view of the rotation of the adjustment seat during loading;

fig. 10 is a schematic view showing the rotation of the adjusting seat during the left and right leisure of the chair.

Detailed Description

The invention is described in further detail below with reference to the drawings and the examples.

The terms of orientation such as up, down, left, right, front, rear, front, back, top, bottom, etc. mentioned or possible in this specification are defined with respect to the configurations shown in the drawings, and the terms "inner" and "outer" refer to the relative concepts of the terms toward or away from the geometric center of a particular component, respectively, and thus may be changed accordingly depending on the location and use state of the component. These and other directional terms should not be construed as limiting terms.

Referring to fig. 1 to 10, a chair comprises two left and right spaced chair frames 1, a seat layer 2 fixed by the two chair frames 1 and spread left and right, a chair leg frame 4, and a base mechanism 3 connected with the chair leg frame 4.

Wherein, the chair frame 1 comprises a chair seat frame 11 which basically extends forwards and backwards, a chair back frame 12 which basically extends upwards and downwards, a connecting frame 13 which connects the rear end of the chair seat frame 11 and the bottom end of the chair back frame 12, and a framework 14. It should be noted that the seat frame 11 and the back frame 12 are not linear structures, but exhibit a certain curvature based on ergonomics, but extend in a front-rear direction and up-down direction as a whole.

The seat surface layer 2 has a surface layer structure with certain stretching degree and can be tensioned, can support buttocks of a user and back of the user, is preferably made of mesh cloth, has the characteristics of good fabric air permeability, large friction force and softness, and has excellent air permeability and rebound resilience under the condition of ensuring bearing. Specifically, the seat layer 2 includes a seat layer 21 fixed by the two seat frames 11 and spread left and right, and a seat back layer 22 fixed by the two seat back frames 12 and spread left and right.

The connecting frame 13 is made of elastic material, such as rubber, silica gel, natural rubber, and the like, and has strong performance of being pressed, bent, deformed and rebounded to restore to the original shape. The frame 14 is made of rigid material, such as stainless steel, and has high structural strength. The engagement member is in an arc-shaped segment structure, and naturally transitions the front-rear extending direction of the seat frame 11 to the up-down extending direction of the back frame 12.

When the connecting frame 13 is not provided with the framework 14, the connecting frame can be bent and deformed so that the chair back frame 12 can be turned forwards, and the chair back frame 12 and the chair seat frame 11 are folded and folded, so that the space occupied by the chair vertically can be compressed, and the cabinet loading amount is improved. When the frame 14 is assembled on the connecting frame 13, i.e. after the chair is assembled, the frame 14 can support the connecting frame 13 so that the connecting frame 13 can maintain the original shape without deformation, thereby making the chair frame 1 a firm and stable structure.

The chair seat frame 11 and the chair back frame 12 need to have certain rigidity as the supporting main body of the chair frame 1, so that the chair frame 1 is a foldable structure body which is soft and elastic only at the bending part of the foldable structure body, compared with other mechanical structures such as joints, hinges and the like, the foldable structure body has fewer components and parts, and the whole structure is simpler, so that mechanical faults are not easy to occur, and meanwhile, the production cost is relatively lower.

Further, the engagement frame 13 has a mounting groove 131 recessed inward on one surface thereof and extending in the extending direction of the engagement frame 13, and the frame 14 is fitted into the mounting groove 131. The mounting groove 131 is preferably provided on the inner side of the connecting frame 13, so that the frame 14 is prevented from being exposed to the outside to affect the appearance, and the possibility of damage to the frame 14 due to the collision or other external environments is reduced. The frame 14 is in an arc-shaped sheet structure in structural shape, and of course, because the connecting frame 13 is made of elastic materials, the frame 14 is made of rigid materials, and the frame 14 is slightly larger than the mounting groove 131 in size, so that the frame 14 is embedded in the mounting groove 131 in an interference manner, and the frame 14 is prevented from loosening and becoming more and faster in the mounting groove 131. In addition, it is desirable to increase the widths of the frame 14 and the mounting groove 131 as much as possible so that the frame 14 has better supporting performance.

In order to further improve the structural strength and structural stability of the assembled chair frame 1, one surface of the chair seat frame 11 and one surface of the chair back frame 12 are respectively provided with an extension groove 132 connected with the mounting groove 131, and obviously, the surface where the extension groove 132 is positioned is the inner side surface of the chair seat frame 11 and the chair back frame 12. Both ends of the frame 14 are respectively inserted into the corresponding extension grooves 132, and similarly, the frame 14 is slightly larger than the extension grooves 132 in size.

The two ends of the framework 14 are detachably connected with the chair seat frame 11 and the chair back frame 12 respectively, compared with the connecting frame 13 made of elastic materials, the framework 14 is fixedly connected with the chair seat frame 11 and the chair back frame 12, so that the connection stability is better, and the detachable connection mode is also convenient for the disassembly and assembly of the chair frame 1. More specifically, the frame 14 is fixedly connected to the seat frame 11 and the back frame 12 by a plurality of fasteners.

In order to increase the load of the shearing stress applied to the connecting frame 13 and to increase the structural strength of the connecting frame 13 in the inner and outer width directions, the bottom of the mounting groove 131 is provided with at least one reinforcing groove 133 which is recessed inward and extends along the extending direction of the mounting groove 131, and the surface of the framework 14 attached to the bottom of the mounting groove 131 is provided with a reinforcing structure 141 inserted into the reinforcing groove 133. More specifically, two reinforcing grooves 133 are formed at the intersection of the groove bottom of the mounting groove 131 and the two groove walls, and corresponding reinforcing structures 141 are formed on two sides of the skeleton 14.

The engagement frame 13 has a plurality of partition grooves 134 arranged at intervals along the extending direction thereof, and the partition grooves 134 form notches at least in the inner curved surface of the engagement frame 13. In the present embodiment, the partition groove 134 is formed with notches in the inner side surface and the top surface (inner curved surface). The groove width of the partition groove 134 is continuously compressed in the gradual folding process of the connecting piece, so that the buffer effect is achieved, irreversible deformation damage caused by too high local extrusion force of the connecting frame 13 when the seat frame 11 and the seat back frame 12 are folded can be avoided, and meanwhile, the partition groove 134 can also enable the connecting frame 13 to be easier to bend, so that the labor is saved during folding. The number, spacing, and width of the partition grooves 134 are determined according to the actual application.

Although the link frame 13 can be supported by the frame 14 and the link members can be connected to the seat frame 11 and the back frame 12 well, misalignment and offset easily occur between the two ends of the link frame 13 and the rear end of the seat frame 11 and the bottom end of the back frame 12. Therefore, a connecting member 15 is provided between both ends of the link frame 13 and the rear end of the seat frame 11/the bottom end of the back frame 12 for connecting both ends of the link member and the rear end of the seat frame 11/the bottom end of the back frame 12. Because the connecting piece is made of elastic materials, one part of the connecting piece 15 is embedded into the connecting frame 13, and the other part is fixed on the chair seat frame 11/the chair back frame 12. The part of the connecting piece 15 embedded into the connecting frame 13 plays a role similar to the framework 14 and supports the end part of the connecting frame 13, and the other part of the connecting piece 15 is fixedly connected with the chair seat frame 11/the chair back frame 12, so that the connection stability can be improved.

More specifically, the connecting member 15 includes a first connecting member portion 151 and a second connecting member portion 152, where the first and second connecting member portions 152 are plate-shaped structures, and are integrally connected in a folded angle relationship. The connecting piece 15 is the same as the framework 14 and is also made of rigid materials. The bottoms of the mounting grooves 131 near the two ends are respectively provided with an inward concave caulking groove 135, the first connecting piece portion 151 is embedded in the caulking groove 135, and the first connecting piece portion 151 is slightly larger than the caulking groove 135 in size, so that the first connecting piece portion 151 is not easy to loosen in the caulking groove 135. The second connector portion 152 is fitted to the bottoms of the mounting grooves 131 and the extending grooves 132, and the frame 14 is fitted to the second connector portion 152, so that the second connector portion 152 is sandwiched between the bottoms of the mounting grooves 131 and the extending grooves 132 and the frame 14, and the second connector portion 152 and the extending grooves 132 are fixed together. Firstly, the connecting piece 15 not only plays a role of connecting the end part of the connecting piece and the rear end of the seat frame 11/the bottom end of the seat back frame 12, but also can further improve the load of the shearing stress applied to the two ends of the connecting piece when the first connecting piece 151 is inserted into the caulking groove 135; and the attachment member second portion 152 is sandwiched between the mounting groove 131, the groove bottom of the extension groove 132 and the frame 14 to enhance the securement to the seat frame 11/back frame 12. In addition, a plurality of fasteners are also removably secured between the connector second portion 152 and the extension slot 132.

The two seat frames 11 are detachably connected to the left and right ends of the base mechanism 3, and when the chair is used for loading a cabinet, the two seat frames 11 can be compressed and folded left and right, and the seat layer 2 is folded at the same time, so that the space occupied by the chair in the transverse direction can be compressed.

The space occupied by the chair is compressed in the transverse direction and the vertical direction, so that the cabinet loading amount of the chair can be greatly improved, and the cost of logistics transportation is saved.

It should be noted that, in order to avoid the seat surface layer 21 from collapsing downward directly when the user sits at his or her end after the chair is assembled, the seat surface layer 21 is in a tension state, i.e., the seat surface layer 21 is stretched left and right to a certain extent, so that the buttocks of the user can be stably supported. However, when the seat surface layer 21 is naturally opened left and right, the left-right distance between the two seat frames 11 is smaller than the left-right distance between the assembled seat frames, which results in a certain dimensional deviation during installation, that is, it is necessary to connect the seat frames 11 and the base unit 3 in a state in which the seat surface layer 21 is stretched left and right. It is difficult for a user to maintain the seat surface layer 21 stretched open without tools during assembly and to control the magnitude of stretching, thereby making alignment of the seat frame 11 and the base unit 3 difficult.

Based on this technical problem, the base mechanism 3 includes a base 31, two adjusting seats 32 detachably connected to the corresponding seat frames 11, the two adjusting seats 32 are rotatably connected to the left and right ends of the base 31, respectively, and the rotation axes of the two adjusting seats extend in the front-rear direction, and the two adjusting seats 32 can rotate in opposite directions so that the left-right distance between the two seat frames 11 is changed. The left-right distance between two ends of the base mechanism 3 can be reduced when the two adjusting seats 32 are turned upwards relative to the base 31, and a user can neglect whether the seat surface layer 21 is stretched or not when assembling, firstly, the two seat frames 11 are fixedly connected with the corresponding adjusting seats 32 respectively, then the two seat frames 11 are pressed downwards or the base 31 is pushed upwards, the two adjusting seats 32 can be turned downwards relative to the base 31, so that the left-right distance between the two seat frames 11 is increased, namely, the seat surface layer 21 is stretched to be in a tensioning state.

After the two adjusting seats 32 are turned down to be flush with the base 31, if the two adjusting seats are turned down, the left-right distance between the two seat frames 11 is reduced, so the base 31 and the adjusting seats 32 respectively have a first limiting structure 311 and a second limiting structure 321 which can be blocked mutually, and the first limiting structure and the second limiting structure are used for limiting the maximum threshold value of the left-right distance between the two seat frames 1. Due to the influence of the self-weight of the seat frame 11 and the adjustment seat 32, the adjustment seat 32 and the base 31 can be stably maintained in a state in which the first and second stopper structures 311 and 321 are blocked from each other without receiving an external force. In addition, when the first limiting structure 311 and the second limiting structure 321 block each other, the adjusting seat 32 may be flush with the base 31, or the adjusting seat 32 may be slightly tilted upward relative to the base 31.

The seat frame 11 and the adjusting seat 32 are respectively provided with a slot 111 and an inserting structure 322, the inserting structure 322 is inserted into the slot 111 and used for limiting the relative positions of the seat frame 11 and the adjusting seat 32, the seat frame 11 and the adjusting seat 32 are detachably connected by using a plurality of fasteners, and when the seat frame is assembled, the inserting structure 322 of the adjusting seat 32 is inserted into the slot 111 of the seat frame 11 and then connected by using the fasteners, so that the connection installation position is conveniently found.

Since the adjusting seat 32 is rotated to adjust the position, it is difficult to achieve that the insertion structure 322 is completely aligned with the slot 111, and thus a gap is provided between the insertion structure 322 and the slot 111, which is convenient for insertion, but easily results in loosening therebetween. Therefore, the adjusting seat 32 has a blocking structure 323, the blocking structure 323 abuts against the side of the seat frame 11 near the base 31 to prevent the seat frame 11 and the adjusting seat 32 from moving relatively, and a slot is formed between the inserting structure 322 and the blocking structure 323, so as to realize the mutual insertion of the seat frame 11 and the adjusting seat 32.

It should be noted that when the seat layer 2 is loaded and pressed (when the user sits on the seat layer 21), the tension of the seat layer 21 will increase, especially when the user sits on the seat layer 21 quickly, which is heavy, and this situation will easily cause irreversible tensile damage to the seat layer 21, shortening the service life, and also easily damaging the edge of the seat layer 21 fixed on the seat frame 11. Because of the rotation connection relation between the adjusting seat 32 and the base 31, when the seat layer 2 is pressed, the rapid increase of the tension degree of the seat layer 21 applies acting force to the seat frames 11, so that the adjusting seat 32 can turn upwards relative to the base 31, the left-right distance between the two seat frames 11 is shortened, the rapid increase degree of the tension degree of the seat layer 21 is reduced, a certain buffer effect is achieved, the damage to the seat layer 21 can be reduced, the service life of the seat layer 21 is prolonged, a certain elastic buffer effect is provided, the hardness of a user sitting on the seat layer 21 is reduced, and the comfort is improved.

The two adjustment seats 32 are rotated in opposite directions (i.e., the two adjustment seats 32 are simultaneously flipped up or simultaneously flipped down with respect to the base 31) so that the left-right spacing of the two seat frames 1 is changed, and the two adjustment seats 32 are rotated in the same direction (i.e., one adjustment seat 32 is flipped up with respect to the base 31 and the other adjustment seat 32 is flipped down with respect to the base 31) so that the left-right tilting amplitude of the two seat layers 2 is changed. When the user sits on the seat surface layer 21 and leans the body to the left or right, the two adjustment seats 32 are rotated in the same direction, thereby enabling the chair to have a left and right leisure function. Correspondingly, the first limiting structure 311 and the second limiting structure 321 which are blocked mutually can also be used for limiting the maximum downward turning angle of the adjusting seat 32 relative to the base 31, namely limiting the maximum amplitude of the left-right ease.

A first elastic restoring member 3-1 is disposed between the base 31 and the adjusting seat 32, and the first elastic restoring member 3-1 is used for driving the adjusting seat 32 to rotate and restore, preferably using a spring, so that the auxiliary seat surface layer 21 and the base junction layer quickly restore to a horizontal state when the user gets up or sits.

At least one supporting frame 5 is arranged between the two chair frames 1, the left end and the right end of the supporting frame 5 are respectively connected with the corresponding chair frames 1, the supporting frames 5 always apply supporting force for resisting continuous reduction of the left-right distance to the two chair frames 1 in the process that the left-right distance between the two chair frames 1 is gradually reduced by a maximum threshold value, so that the degree of the tension surge of the seat surface layer 21 can be further reduced in a chair manner, and the buffering effect is improved. In addition, the left and right ends of the supporting frame 5 are detachably connected with the corresponding chair frame 1, and the chair frame 11 is connected with the adjusting seat 32 first during assembly, and then the supporting frame 5 is connected. In this embodiment, the supporting frame 5 is a long sheet structure with a certain bending degree, and is made of plastic material, so that it can bear a certain bending deformation.

The support frame 5 is used as a beam structure directly connected with the two chair frames 1, the support frames 5 are respectively arranged between the front parts of the two chair frames 11 and between the front parts of the adjusting seats 32 and the upper parts of the two chair back frames 12, so that the two chair frames 11 and the two support frames 5 form a closed structure, and the overall structural stability and the deformation resistance can be improved.

The waist support 6 is arranged between the two chair back frames 12 at the position corresponding to the waist of the user, the left end and the right end of the waist support 6 are respectively connected with the corresponding chair back frames 12, the chair back surface layer 22 can be supported, the waist can be well supported when the rear part of the user is completely supported on the chair back surface layer 22, the ergonomic requirement is met, and the comfort level can be improved.

In addition, the base 31 is rotatably connected to the top end of the chair leg frame 4, and the rotation axis thereof extends in the left-right direction, so that the chair has a function of back-and-forth ease, and the two functions of back-and-forth ease and left-and-right ease are independent of each other and do not interfere with each other. A second elastic restoring member 3-2 is arranged between the base 31 and the top end of the chair leg frame 4, and is used for driving the base 31 to rotate and restore, and the second elastic restoring member 3-2 is preferably a spring.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme recorded in each embodiment can be modified or part of technical features in the technical scheme can be replaced equivalently; such modifications and substitutions do not depart from the spirit of the invention.

Claims

1. The chair is characterized by comprising two chair frames which are arranged at intervals left and right, a chair surface layer which is fixed by the two chair frames and is unfolded left and right, a chair foot rest and a base which is connected with the chair foot rest; the two chair frames are provided with adjusting seats which are movably connected with the base; when the load of the seat layer is pressed, the adjusting seat drives the seat frame to move relative to the base so as to buffer the rapid increase of the tension of the seat layer; the two adjusting seats are respectively connected to the left end and the right end of the base in a rotating way, and the rotating axes of the two adjusting seats extend along the front-back direction; the two adjusting seats can rotate in opposite directions to change the left-right distance between the two chair frames, and rotate in the same direction to change the left-right inclination amplitude of the two chair surface layers.

2. The chair according to claim 1, wherein said base and said adjustment seat have first and second stop structures, respectively, that are mutually engageable to define a maximum angle at which the adjustment seat is turned downwardly relative to the base and a maximum threshold defining a side-to-side spacing between said two frames.

3. A chair according to claim 1 or 2, wherein a first resilient return member is provided between the base and the adjustment seat for urging the adjustment seat to rotate and return.

4. The chair according to claim 1, wherein at least one supporting frame is provided between the two chair frames, and the left and right ends of the supporting frame are respectively connected with the corresponding chair frames; and the supporting frames always apply supporting force for resisting the continuous reduction of the left-right spacing to the two chair frames in the process that the left-right spacing of the two chair frames is gradually reduced by the maximum threshold value.

5. The chair according to claim 4, wherein the chair frame includes a back-and-forth extending chair frame and a back-and-forth extending chair frame; the seat surface layer comprises a seat surface layer fixed by two seat frames and stretched left and right, and a seat back surface layer fixed by two seat back frames and stretched left and right.

6. The chair according to claim 5, wherein said support frames are respectively provided between the front portions of said seat frames and between the upper portions of said back frames in front of said adjustment seat.

7. The chair according to claim 5, wherein a lumbar support is provided between the two back frames corresponding to the lumbar region of the user, and the left and right ends of the lumbar support are respectively connected to the corresponding back frames and can support the back surface layer.

8. The chair according to claim 1, wherein said base is rotatably connected to the top end of said chair leg and the rotation axis thereof extends in the left-right direction.

9. The chair according to claim 8, wherein a second resilient return member is provided between said base and said top end of said foot rest for urging said base to rotate and return.