CN218635648U

CN218635648U - Chair backrest and chair

Info

Publication number: CN218635648U
Application number: CN202222397323.1U
Authority: CN
Inventors: 罗慧平; 叶云青; 曹旭林; 谢文科; 严业龙
Original assignee: Foshan Kezhimei Furniture Co ltd
Current assignee: Foshan Kezhimei Furniture Co ltd
Priority date: 2022-09-08
Filing date: 2022-09-08
Publication date: 2023-03-17
Anticipated expiration: 2032-09-08

Abstract

The utility model discloses a chair back and chair, chair back, include: the chair comprises a chair back bracket, wherein a first positioning groove is formed in the front side part of the chair back bracket; and the waist supporting mechanism comprises an elastic component and a waist supporting piece, the elastic component comprises a first mounting piece, a second mounting piece arranged at an interval with the first mounting piece, and the elastic supporting piece connected between the first mounting piece and the second mounting piece, the first mounting piece is arranged in the first positioning groove, the waist supporting piece is arranged at the front side of the chair back support, a second positioning groove is formed in one side, close to the chair back support, of the waist supporting piece, and the second mounting piece is arranged in the second positioning groove. The utility model provides a chair back and chair can improve the travelling comfort that the user sat.

Description

Chair backrest and chair

Technical Field

The utility model relates to a chair technical field, in particular to chair back and chair.

Background

The chair is a tool commonly used in daily life of people and comprises an office chair, a competitive electric chair and the like according to the classification.

In the related art, in order to improve the comfort of the waist of the user when the user sits on a chair, some chairs are provided with a waist pillow to support the waist of the user, so that the fatigue of the user is reduced. However, most waist pillow is all the snap-on the back of chair at present, and this can lead to the travelling comfort not good enough to, to the great user of size, because the waist pillow can occupy certain space in cushion top, can lead to this type of user's buttock and the area of contact of cushion little, thereby lead to the user to sit uncomfortably.

SUMMERY OF THE UTILITY MODEL

The utility model discloses aim at solving one of the technical problem that exists among the prior art at least. Therefore, the utility model provides a chair back and chair for improve the travelling comfort that the user sat up.

According to the utility model discloses chair back of first aspect embodiment includes: the chair comprises a chair back bracket, wherein a first positioning groove is formed in the front side part of the chair back bracket; and a lumbar support mechanism, the lumbar support mechanism comprises an elastic component and a lumbar support part, the elastic component comprises a first installation part, a second installation part arranged at intervals of the first installation part and an elastic support part connected between the first installation part and the second installation part, the first installation part is arranged in the first positioning groove, the lumbar support part is arranged at the front side of the chair back support, the lumbar support part is close to one side of the chair back support is provided with a second positioning groove, and the second installation part is arranged in the second positioning groove.

According to the utility model discloses chair back has following beneficial effect at least:

the utility model discloses an among the chair back, when the user sat on the chair, lumbar support mechanism was used for supporting user's waist, so, can improve the travelling comfort of user waist when sitting. Particularly, when the user sits on the chair, the waist of the user is attached to the waist support part, and under the action of the elastic support part, the waist support part can provide elastic support for the waist of the user, so that the user feels more comfortable. Moreover, aiming at the users with larger body sizes, the chair with the chair backrest of the utility model can provide comfortable feelings for the users. For example, to the great user of size, when this user sat on the chair, this user can extrude lumbar support spare and make elastic support spare shrink to make lumbar support spare be close to the back of the chair support more, so, the user can further sit backward, makes the area of contact increase of user's buttock and cushion, thereby improves user's travelling comfort.

In addition, in the chair back of the present invention, the elastic member is connected to the back support through the first mounting member. When the first mounting piece and the chair back support are assembled, the first mounting piece can be arranged in the first positioning groove to realize the pre-positioning of the first mounting piece and the chair back support, so that the assembly precision of the first mounting piece and the chair back support can be improved, and the subsequent assembly of the first mounting piece and the chair back support is facilitated; and, when assembly second installed part and lumbar support piece, can set up the second installed part in the second constant head tank earlier, realize the prepositioning of second installed part and lumbar support piece to can improve the assembly precision of second installed part and lumbar support piece, and make things convenient for the follow-up assembly of second installed part and lumbar support piece.

According to some embodiments of the utility model, the chair back still include first fastener, first installed part is equipped with first pilot hole, the cell wall of first constant head tank seted up with the second pilot hole that first pilot hole corresponds, first fastener is worn to locate first pilot hole and second pilot hole.

According to some embodiments of the utility model, the chair back still include the second fastener, the second installed part is equipped with the third pilot hole, the cell wall of second constant head tank seted up with the fourth pilot hole that the third pilot hole corresponds, the second fastener is worn to locate the third pilot hole and the fourth pilot hole.

According to the utility model discloses a some embodiments, the third pilot hole include the holding section and with the spacing section of holding section intercommunication, the holding section is located spacing section is close to one side of first installed part, the second fastener is the screw, the screw is worn to locate in proper order the holding section spacing section and the fourth pilot hole, and make the screwhead of screw arrange in the holding section.

According to some embodiments of the present invention, the aperture of the accommodation section is larger than the aperture of the spacing section.

According to some embodiments of the invention, the second mounting member includes a mounting member body and a protrusion provided in one side of the first mounting member is kept away from by the mounting member body, the accommodation section runs through the mounting member body and extends to the inside of the protrusion, the spacing section runs through the protrusion is kept away from one side of the mounting member body.

According to some embodiments of the present invention, a first buffering protrusion is disposed on a side of the first mounting member away from the second mounting member, and the first buffering protrusion abuts against a groove wall of the first positioning groove;

the number of the first buffering bulges is multiple, and the first buffering bulges are arranged at intervals.

According to some embodiments of the present invention, a second buffering protrusion is disposed on a side of the second mounting member away from the first mounting member, and the second buffering protrusion abuts against a groove wall of the second positioning groove;

the number of the second buffer bulges is multiple, and the multiple second buffer bulges are arranged at intervals.

According to some embodiments of the present invention, the number of lumbar support mechanisms is two, two the lumbar support mechanisms are followed the width direction interval of the back of the chair support sets up.

The chair according to the embodiment of the second aspect of the invention comprises the chair backrest.

According to the utility model discloses chair has following beneficial effect at least:

the utility model discloses an in the chair, when the user sits on the chair, lumbar support mechanism is used for supporting user's waist, so, can improve the travelling comfort of user's waist when sitting. Particularly, when the user sits on the chair, the waist of the user is attached to the waist support part, and under the action of the elastic support part, the waist support part can provide elastic support for the waist of the user, so that the user feels more comfortable. Moreover, the chair with the chair backrest can provide comfortable feeling for the users with large body sizes. For example, to the great user of size, when this user sat on the chair, this user can extrude lumbar support spare and make elastic support spare shrink to make lumbar support spare be close to the back of the chair support more, so, the user can further sit backward, makes the area of contact increase of user's buttock and cushion, thereby improves user's travelling comfort.

Additionally, in the chair of the present invention, the elastic member is connected to the back support through the first mounting member. When the first mounting piece and the chair back support are assembled, the first mounting piece can be arranged in the first positioning groove to realize the pre-positioning of the first mounting piece and the chair back support, so that the assembly precision of the first mounting piece and the chair back support can be improved, and the subsequent assembly of the first mounting piece and the chair back support is facilitated; and, when assembly second installed part and lumbar support piece, can set up the second installed part in the second constant head tank earlier, realize the prepositioning of second installed part and lumbar support piece to can improve the assembly precision of second installed part and lumbar support piece, and make things convenient for the follow-up assembly of second installed part and lumbar support piece.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The invention will be further described with reference to the following drawings and examples, in which:

fig. 1 is a schematic structural view of a chair according to an embodiment of the present invention;

FIG. 2 is an enlarged view taken at A in FIG. 1;

fig. 3 is a schematic structural view of a lumbar support mechanism according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of an elastic component according to an embodiment of the present invention;

fig. 5 is a partial structural schematic view of a chair according to an embodiment of the present invention;

fig. 6 is an enlarged view at B in fig. 5.

Reference numerals:

100. a chair back bracket; 110. a first positioning groove;

200. a lumbar support mechanism; 210. an elastic member; 211. a first mounting member; 2111. a first fitting hole; 2112. a first buffer projection; 212. an elastic support member; 213. a second mount; 2131. a mounting member body; 2132. a protrusion; 2133. a second buffer projection; 2134. a third assembly hole; 21341. an accommodating section; 21342. a limiting section; 220. a lumbar support; 221. a second positioning groove; 222. digging a dead zone;

300. a cushion.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present invention. Furthermore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected" and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

As shown in fig. 1, a chair according to an embodiment of the present invention includes a chair back for a user to lean against. It will be appreciated that the chair also includes a seat cushion 300 that rests against the back of the chair when a user is seated on the seat cushion 300.

It should be noted that, in the present embodiment, the chair further includes chair legs (not shown) for supporting the seat cushion 300. Wherein, the chair leg is provided with a roller wheel which can move on the ground.

As shown in fig. 1, the chair back includes a back bracket 100 and a lumbar support mechanism 200.

As shown in fig. 5 and 6, a first positioning groove 110 is formed in the front side of the seat back bracket 100.

Specifically, the back bracket 100 is located at a rear side portion of the chair, and a first positioning groove 110 is provided at a front side portion of the back bracket 100.

As shown in fig. 2 and 3, the lumbar support mechanism 200 includes an elastic member 210 and a lumbar support member 220.

As shown in fig. 1 and 2, the lumbar support 220 is disposed at the front side of the seat back bracket 100 and above the seat cushion 300, and a second positioning slot 221 is disposed at a side of the lumbar support 220 close to the seat back bracket 100.

As shown in fig. 2, 4 and 6, the elastic assembly 210 includes a first mounting part 211, a second mounting part 213 spaced apart from the first mounting part 211, and an elastic supporting part 212 connected between the first mounting part 211 and the second mounting part 213, wherein the first mounting part 211 is disposed in the first positioning groove 110, and the second mounting part 213 is disposed in the second positioning groove 221.

The elastic support 212 may be an elastic member such as a spring, a leaf spring, or elastic rubber.

In the chair backrest of the present invention, when the user sits on the chair, the lumbar support mechanism 200 is used to support the waist of the user, so that the comfort of the waist of the user when sitting can be improved. Specifically, when the user sits on the chair, the user's waist is fitted to the lumbar support 220, and under the action of the elastic support 212, the lumbar support 220 can provide elastic support for the user's waist, so that the user feels more comfortable. Moreover, the chair with the chair backrest can provide comfortable feeling for the users with large body sizes. For example, for a user with a large size, when the user sits on a chair, the user may press the waist support 220 to contract the elastic support 212, so that the waist support 220 is closer to the chair back bracket 100, and thus, the user can further sit back, so that the contact area between the buttocks of the user and the seat cushion 300 is increased, and the comfort of the user is improved.

In addition, in the chair back of the present invention, the elastic member 210 is connected to the back bracket 100 through the first mounting member 211. When the first mounting member 211 and the seat back bracket 100 are assembled, the first mounting member 211 may be first disposed in the first positioning groove 110 to achieve the pre-positioning of the first mounting member 211 and the seat back bracket 100, so that the assembly accuracy of the first mounting member 211 and the seat back bracket 100 may be improved, and the subsequent assembly of the first mounting member 211 and the seat back bracket 100 is facilitated; moreover, when the second mounting member 213 and the lumbar support member 220 are assembled, the second mounting member 213 may be disposed in the second positioning groove 221 first, so as to achieve the pre-positioning of the second mounting member 213 and the lumbar support member 220, thereby improving the assembling accuracy of the second mounting member 213 and the lumbar support member 220, and facilitating the subsequent assembling of the second mounting member 213 and the lumbar support member 220.

It should be noted that the first mounting element 211 is disposed in the first positioning groove 110, and the periphery of the first mounting element 211 contacts with the sidewall of the first positioning groove 110, so that the sidewall of the first positioning groove 110 can be used to position the first mounting element 211; the second mounting member 213 is disposed in the second positioning groove 221, and the periphery of the second mounting member 213 contacts with the sidewall of the second positioning groove 221, so that the sidewall of the second positioning groove 221 can be used to position the second mounting member 213.

As shown in fig. 4 and 6, in one embodiment, the chair back further includes a first fastening member (not shown), the first mounting member 211 is provided with a first mounting hole 2111, a groove wall of the first positioning groove 110 is provided with a second mounting hole corresponding to the first mounting hole 2111, and the first fastening member is inserted into the first mounting hole 2111 and the second mounting hole, so that the first mounting member 211 is fixedly connected to the chair back bracket 100.

Optionally, the first fastening member is a screw, the first assembling hole 2111 is a through hole, the second assembling hole is a screw hole, and the first fastening member sequentially penetrates through the first assembling hole 2111 and the second assembling hole; or, the first fastening piece is a screw, the first assembling hole 2111 is a screw hole, the second assembling hole is a through hole, and the first fastening piece sequentially penetrates through the second assembling hole and the first assembling hole 2111; alternatively, the first fastener is a dowel, and the first assembly hole 2111 and the second assembly hole are both pin holes.

As shown in fig. 2 and 4, the chair back further includes a second fastening member (not shown), the second mounting member 213 has a third mounting hole 2134, a groove wall of the second positioning groove 221 has a fourth mounting hole corresponding to the third mounting hole 2134, and the second fastening member is inserted into the third mounting hole 2134 and the fourth mounting hole, so that the second mounting member 213 is fixedly connected to the lumbar support 220.

Optionally, the second fastener is a screw, the third assembling hole 2134 is a through hole, the fourth assembling hole is a screw hole, and the second fastener sequentially penetrates through the third assembling hole 2134 and the fourth assembling hole; or the second fastener is a screw, the third assembling hole 2134 is a screw hole, the fourth assembling hole is a through hole, and the second fastener sequentially penetrates through the fourth assembling hole and the third assembling hole 2134; alternatively, the second fastener is a pin, and the third assembly hole 2134 and the fourth assembly hole are both pin holes.

As shown in fig. 2 and 4, the third assembling hole 2134 further includes a receiving section 21341 and a limiting section 21342 communicated with the receiving section 21341, the receiving section 21341 is located on one side of the limiting section 21342 close to the first mounting part 211, the second fastening member is a screw, the screw is sequentially inserted through the receiving section 21341, the limiting section 21342 and the fourth assembling hole, and a screw head of the screw is placed in the receiving section 21341. The receiving portion 21341 may be configured to receive a head of a screw, so as to hide the head of the screw, thereby improving the appearance.

Specifically, the second fastener is a screw, the third assembly hole 2134 is a through hole, and the fourth assembly hole is a screw hole. The third assembling hole 2134 includes a receiving section 21341 and a limiting section 21342, the receiving section 21341 is located on one side of the limiting section 21342 close to the first mounting element 211, an aperture of the receiving section 21341 is larger than an aperture of the limiting section 21342, and the receiving section 21341 can enable a bolt head of a bolt to penetrate through the receiving section 21341. Thus, when the second mounting member 213 and the lumbar support 220 are fixed together by the screw, the screw may be sequentially inserted into the receiving section 21341, the limiting section 21342 and the fourth assembling hole, and the screw head of the screw is placed in the receiving section 21341.

Further, the second mounting element 213 includes a mounting element body 2131 and a protrusion 2132 disposed on a side of the mounting element body 2131 away from the first mounting element 211, the receiving segment 21341 penetrates through the mounting element body 2131 and extends into the protrusion 2132, and the limiting segment 21342 penetrates through a side of the protrusion 2132 away from the mounting element body 2131. By providing the protrusion 2132 on the side of the mount body 2131 away from the first mount 211, the local thickness of the mount body 2131 is increased, so that the accommodating section 21341 has enough space for accommodating the screw head of the screw.

In one embodiment, as shown in fig. 3 and 6, a first buffering protrusion 2112 is provided at a side of the first mounting part 211 far from the second mounting part 213, and the first buffering protrusion 2112 abuts against a groove wall of the first positioning groove 110. After the first mounting member 211 is fixed to the seat back bracket 100, the first buffering protrusion 2112 abuts against the groove wall of the first positioning groove 110, and the first buffering protrusion 2112 can provide a buffering effect for the first mounting member 211.

Specifically, since the frequency of the user sitting on the chair is relatively high, when the user leans on the lumbar support 220, the first mounting part 211 receives an instantaneous impact force and transmits the impact force to the seat back bracket 100, and the first buffering protrusion 2112 is provided at a side of the first mounting part 211 away from the second mounting part 213, and the first buffering protrusion 2112 abuts against a groove wall of the first positioning groove 110, so that the impact force can be reduced by the first buffering protrusion 2112, thereby prolonging the service life.

Specifically, a side of the first mounting part 211, which is far away from the second mounting part 213, is provided with a first buffer sheet, and the first buffer protrusion 2112 is provided on the first buffer sheet.

More specifically, the first buffer sheet is bonded to the first mounting member 211, and the first buffer sheet is integrally structured with the first buffer protrusion 2112.

It is understood that the first buffer sheet and the first buffer protrusion 2112 are rubber members.

Further, the number of the first buffer protrusions 2112 is plural, and the plural first buffer protrusions 2112 are arranged at intervals. Thus, the buffering effect can be further improved.

As shown in fig. 2 and 4, in one embodiment, a second buffering protrusion 2133 is disposed on a side of the second mounting member 213 away from the first mounting member 211, and the second buffering protrusion 2133 abuts against a groove wall of the second positioning groove 221. After the second mounting member 213 and the lumbar support 220 are fixed together, the second buffering protrusion 2133 abuts against the groove wall of the second positioning groove 221, and the second buffering protrusion 2133 can provide a buffering effect for the second mounting member 213.

Specifically, since the frequency of the user sitting on the chair is high, when the user leans on the lumbar support 220, the lumbar support 220 receives an instantaneous impact force and transmits the impact force to the second mounting member 213, and the second buffering protrusion 2133 is provided on the side of the second mounting member 213 away from the first mounting member 211, and the second buffering protrusion 2133 abuts against the groove wall of the second positioning groove 221, so that the impact force can be reduced by the second buffering protrusion 2133, thereby prolonging the service life.

Specifically, a side of the second mounting part 213 away from the first mounting part 211 is provided with a second buffer sheet, and the second buffer protrusion 2133 is provided on the second buffer sheet.

More specifically, the second cushion sheet is bonded to the second mounting member 213, and the second cushion sheet and the second cushion protrusion 2133 are an integral structure.

It is understood that the second cushion sheet and the second cushion protrusion 2133 are rubber members.

Further, the number of the second buffering protrusions 2133 is multiple, and the multiple second buffering protrusions 2133 are arranged at intervals. Thus, the buffering effect can be further improved.

Referring to fig. 1 and 5, in one embodiment, the number of the lumbar support mechanisms 200 is two, and the two lumbar support mechanisms 200 are spaced apart along the width direction of the seatback frame 100. The two lumbar support mechanisms 200 can simultaneously support the waist of the user, and when the two lumbar support mechanisms 200 are in contact with the waist of the user, the area of the user where the waist is supported can be increased, thereby further improving the comfort of the user.

It should be noted that, because the compressive deformation of the elastic supporting members 212 also acts against the lumbar supporting members 220, when the sitting posture of the user is inclined, the reaction force of the elastic supporting members 212 on the two lumbar supporting members 220 may be uneven, so that the two lumbar supporting members 220 can apply different forces to the waist of the user to urge the user to adjust the sitting posture.

Further, the lumbar support 220 is arc-shaped, and the two lumbar supports 220 can provide a wrapping effect for the user's waist.

As shown in fig. 3, it should be noted that an excavated area 222 is disposed on the lumbar support member 220, and a breathable mesh is further disposed on the lumbar support member 220, and the breathable mesh covers the excavated area 222, so that the breathable mesh can play a role in ventilation, and the comfort of the user is further improved.

Wherein, the waist supporting member 220 is a waist pillow, and the waist pillow can be made of soft material.

In the chair of the present invention, when the user sits on the chair, the lumbar support mechanism 200 is used to support the waist of the user, so that the comfort of the waist of the user when sitting can be improved. Specifically, when the user sits on the chair, the user's waist is fitted to the lumbar support 220, and under the action of the elastic support 212, the lumbar support 220 can provide elastic support for the user's waist, so that the user feels more comfortable. Moreover, the chair with the chair backrest can provide comfortable feeling for the users with large body sizes. For example, for a user with a large size, when the user sits on a chair, the user may press the waist support 220 to contract the elastic support 212, so that the waist support 220 is closer to the chair back bracket 100, and thus, the user can further sit back, so that the contact area between the buttocks of the user and the seat cushion 300 is increased, and the comfort of the user is improved.

In addition, in the chair of the present invention, the elastic member 210 is connected to the back bracket 100 through the first mounting member 211. When the first mounting member 211 and the seat back bracket 100 are assembled, the first mounting member 211 may be first disposed in the first positioning groove 110 to achieve the pre-positioning of the first mounting member 211 and the seat back bracket 100, so that the assembly accuracy of the first mounting member 211 and the seat back bracket 100 may be improved, and the subsequent assembly of the first mounting member 211 and the seat back bracket 100 is facilitated; moreover, when the second mounting member 213 and the lumbar support member 220 are assembled, the second mounting member 213 may be disposed in the second positioning groove 221 first, so as to achieve the pre-positioning of the second mounting member 213 and the lumbar support member 220, thereby improving the assembling accuracy of the second mounting member 213 and the lumbar support member 220, and facilitating the subsequent assembling of the second mounting member 213 and the lumbar support member 220.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A chair back, comprising:

the chair comprises a chair back bracket, wherein a first positioning groove is formed in the front side part of the chair back bracket; and

lumbar support mechanism, lumbar support mechanism includes elastic component and waist support piece, elastic component include first installed part, with second installed part and connection that first installed part interval set up first installed part with elastic support piece between the second installed part, first installed part set up in first constant head tank, waist support piece set up in back of the chair support's front side, just waist support piece is close to one side of back of the chair support is equipped with the second constant head tank, the second installed part set up in the second constant head tank.

2. The chair backrest according to claim 1, further comprising a first fastening member, wherein the first mounting member is provided with a first mounting hole, a groove wall of the first positioning groove is provided with a second mounting hole corresponding to the first mounting hole, and the first fastening member is inserted into the first mounting hole and the second mounting hole.

3. The chair back rest according to claim 1, further comprising a second fastening member, wherein the second mounting member is provided with a third mounting hole, a groove wall of the second positioning groove is provided with a fourth mounting hole corresponding to the third mounting hole, and the second fastening member is inserted through the third mounting hole and the fourth mounting hole.

4. The chair backrest according to claim 3, wherein the third assembling hole comprises an accommodating section and a limiting section communicated with the accommodating section, the accommodating section is located on one side of the limiting section close to the first mounting part, the second fastening member is a screw, the screw is sequentially inserted through the accommodating section, the limiting section and the fourth assembling hole, and a screw head of the screw is arranged in the accommodating section.

5. The chair back rest according to claim 4, wherein the aperture of the receiving section is larger than the aperture of the limiting section.

6. The chair back according to claim 4, wherein the second mounting member comprises a mounting member body and a protrusion provided on a side of the mounting member body away from the first mounting member, the receiving section penetrates through the mounting member body and extends to an inside of the protrusion, and the limiting section penetrates through a side of the protrusion away from the mounting member body.

7. The chair back rest according to claim 1, wherein a side of the first mounting member remote from the second mounting member is provided with a first buffering protrusion, and the first buffering protrusion abuts against a groove wall of the first positioning groove;

8. The chair back rest according to claim 1, wherein a side of the second mounting member remote from the first mounting member is provided with a second buffering projection abutting against a groove wall of the second positioning groove;

the number of the second buffer bulges is multiple, and the second buffer bulges are arranged at intervals.

9. The chair back according to claim 1, wherein the number of the lumbar support mechanisms is two, and the two lumbar support mechanisms are arranged at intervals in a width direction of the back bracket.

10. A chair comprising a chair back rest as claimed in any one of claims 1 to 9.