CN214631140U

CN214631140U - Ergonomic seat

Info

Publication number: CN214631140U
Application number: CN202023329173.8U
Authority: CN
Inventors: 吕成纲; 程军
Original assignee: UE Furniture Co Ltd
Current assignee: UE Furniture Co Ltd
Priority date: 2020-12-30
Filing date: 2020-12-30
Publication date: 2021-11-09
Anticipated expiration: 2030-12-30

Abstract

The utility model discloses an ergonomic chair, which comprises a back support and a chair back component, wherein the back support is configured to be directly or indirectly connected with a chair seat, and the chair back component comprises a back support piece and a waist support piece; the back support piece and the waist support piece are vertically separated and are respectively and rotatably connected to the back bracket, and the respective rotating axes of the back support piece and the waist support piece are arranged along the left and right direction of the seat; when the back support piece and the waist support piece rotate in response to the leaning force of the human body, the rotation directions of the back support piece and the waist support piece are opposite and form a curve which is attached to the back of the human body and is concave backwards; compared with the prior art, the waist support piece and the waist support piece respond to the force of leaning on of a human body and rotate, the lower end of the back support piece rotates backwards, the upper end of the waist support piece rotates backwards, the waist and back of the human body are located between the back support piece and the waist support piece, and the waist support piece is located below the waist, so that the waist is supported effectively and better, and the comfort is high.

Description

Ergonomic seat

Technical Field

The utility model relates to an office furniture field, in particular to ergonomic seat.

Background

The seat with a double-back structure gradually appears in the market, and can be used as an upper back and a lower back or a left back and a right back according to different requirements, and the seat has various characteristics; the upper back and the lower back are used for realizing the separation of the waist and the back of the chair, the chair back is generally divided into a back support piece and a waist support piece, the back support piece is used for supporting the back of a user, and the waist support piece is used for supporting the waist of the user; meanwhile, the upper back and the lower back have the capability of rotating relative to the chair seat, when a user leans backwards, the angle of the two backs can be changed in a self-adaptive mode, and meanwhile the two backs can rotate relative to each other to be attached to the waist and the back of the human body, so that a better supporting effect is achieved; however, in the existing upper and lower double back structure, the waist support member mostly rotates backwards and downwards relative to the back support member, so as to be separated from the waist of the human body more or less, and at the moment, the waist of the user can not be supported sufficiently, and the use comfort is reduced.

Chinese utility model patent CN201759134U provides a movable chair back structure, which is mainly composed of an upper back plate pivoted in front of a chair back frame, a lower back plate connected to the lower end of the upper back plate via an elastic sheet, and a chair back frame connected to the lower back plate via an elastic plate, so that the lower back plate can swing forward, backward, leftward and rightward relative to the upper back plate; however, when the user leans backwards, the lower back plate is stressed to enable the lower end of the lower back plate to rotate backwards, and the lower back plate can be separated from the waist of the human body at the moment, so that the comfort is reduced.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problem, the utility model provides an ergonomic chair, divide into the back of the chair about two backs, two back of the chair all can rotate separately from top to bottom, and go up the back turning point above, the back turning point is in the below down, the upper and lower back is adjoined the department and is rotated backward jointly, the turned position is in human back central point and puts, consequently can with the better laminating of human back curve, be equivalent to wrap up in with human back middle zone, avoid taking off the waist, accord with ergonomic and really realize the effect of holding in the palm the waist.

The technical scheme of the utility model is realized like this:

an ergonomic chair comprising:

a back support configured to connect to a seat;

the chair back component is arranged on the front side of the back bracket and is configured to support the waist and the back of a human body; the chair back component comprises a back support piece and a waist support piece, the back support piece is configured to support the back of a human body, and the waist support piece is configured to support the waist of the human body; the back support piece and the waist support piece are vertically separated and are respectively and rotatably connected to the back bracket, and the respective rotating axes of the back support piece and the waist support piece are arranged along the left and right direction of the seat;

when the back support piece and the waist support piece rotate in response to the force of leaning against the human body, the rotation directions of the back support piece and the waist support piece are opposite and form a curve which is fit with the back of the human body and is concave backwards.

The separated back support piece and the waist support piece are rotatably connected to the back bracket, so that the chair back component has better moving performance, can adapt to changeable waist and back curves of a human body and conforms to ergonomics; can rotate according to different body contours and waist-back curves, automatically adjust the state of the back support and the waist support: after the back support piece and the waist support piece rotate to form a curve which is concave backwards, the waist back of the human body is positioned between the back support piece and the waist support piece, namely, the waist support piece is positioned below the waist, so that the waist is effectively supported better, and the comfort is higher.

Preferably, the upper end of the back support member is rotatably connected with the back support, and the lower end of the waist support member is rotatably connected with the back support. Different from the chair back component which rotates in the same direction on the market, the rotation directions of the back support piece and the waist support piece of the chair back component are different, and the waist support piece is not connected with the back support piece, so that the waist support piece cannot rise along with the rotation of the back support piece, and the condition that the waist support piece is separated from the waist of a human body cannot be generated; the curve formed by the rotation of the back support piece and the waist support piece can be fit with the waist and the back of a human body and better support the waist of the human body, and the comfort is better.

Preferably, the back support comprises a generally X-shaped connecting portion having two first connecting arms extending upwardly and two second connecting arms extending downwardly; the back support piece is rotatably connected with the first connecting arm, and the waist support piece is rotatably connected with the second connecting arm. The X-shaped connecting part firstly provides a foundation for the independent rotation of the back supporting piece and the waist supporting piece, and secondly, the model can save materials and reduce the cost.

Preferably, a first rotating seat is arranged on the front surface of the first connecting arm close to the end part, a second rotating seat is arranged on the front surface of the second connecting arm close to the end part, and the first rotating seat and the second rotating seat are respectively provided with a rotating shaft hole which penetrates through the first rotating seat or the second rotating seat along the left-right direction; the back support piece and the waist support piece are both of a frame structure, the back support piece is provided with a first hollow part, the waist support piece is provided with a second hollow part, the back support piece is provided with a first jack corresponding to the first rotating seat and with an opening facing the first hollow part, and the waist support piece is provided with a second jack corresponding to the second rotating seat and with an opening facing the second hollow part; the two first connecting arms enter the first hollow part, and a rotating shaft hole of the first rotating seat is aligned with the first jack and is rotationally connected with the first jack through a rotating shaft inserted in the first rotating seat and the second rotating seat; and the two second connecting arms enter the second hollow part, and the rotating shaft hole of the second rotating seat is aligned with the second jack and is rotatably connected with the rotating shaft hole through the rotating shaft inserted in the second rotating seat. It can be seen that the structure that the back support piece and the waist support piece are rotatably connected to the connecting part is simple, easy to realize, low in cost and convenient to install.

Preferably, the back support member is a frame structure, and comprises a first upper cross rod, a first lower cross rod and two first vertical rods connected with the ends of the first upper cross rod and the first lower cross rod; the shape of the end part of the first connecting arm is fitted with the shape of the joint of the first lower cross rod and the first vertical rod; the waist support piece is of a frame structure and comprises a second upper cross rod, a second lower cross rod and two second vertical rods connected with the ends of the second upper cross rod and the second lower cross rod; the shape of the end part of the second connecting arm is attached to the shape of the joint of the second lower cross rod and the second vertical rod. The overall aesthetic degree of the seat is improved.

Preferably, the back support is a vertical column, the back support is provided with a first rotating shaft seat which is positioned at the upper part of the back support and protrudes forwards and a second rotating shaft seat which is positioned at the lower part of the back support and protrudes forwards, the upper part of the back support is rotatably connected to the first rotating shaft seat, and the lower part of the waist support is rotatably connected to the second rotating shaft seat.

Preferably, the back support member and the waist support member are both provided with skirts for hiding the edges of the mesh cloth. The overall attractiveness of the seat is improved, the appearance of the seat is more atmospheric, and the eyeball is attracted.

Preferably, a first elastic piece is arranged between the back support piece and the back bracket, and the first elastic piece is configured to act on the lower end of the back support piece and provide a resetting force for the back support piece; and a second elastic part is arranged between the waist support part and the back support, and the second elastic part is configured to act on the upper end of the waist support part and provide a resetting force for the waist support part. The setting of first, second elastic component makes back support piece and waist support piece's rotation have the ability of buffering and resilience, and human back of laminating more provides sufficient holding power, has promoted the travelling comfort greatly.

Preferably, the first elastic member and the second elastic member are plastic reset spring pieces. The plastic reset spring plate has mature technology and low cost.

Preferably, the second elastic part is in a shape of a slender strip, and two spaced limiting bosses are arranged at the upper end of the second elastic part; the waist support part is of a frame structure and comprises a second upper cross bar close to the back support part; the second upper cross rod is provided with a mounting groove, the mounting groove is a long groove which is communicated up and down and comprises an access section and a fixed section, the groove width of the fixed section is smaller than that of the access section, the access section is configured to avoid a limiting boss, so that the second elastic piece enters the mounting groove, and the fixed section is configured to prevent the second elastic piece from being separated from the mounting groove when the mounting groove is positioned between two limiting blocks. The second elastic piece is installed on the waist supporting piece without screws, so that the installation is convenient and labor-saving, and the assembly efficiency of the seat is improved.

Preferably, an elastic limiting column is further arranged on the access section, a limiting block is arranged at the end of the elastic limiting column, the limiting block is located at the position where the access section is adjacent to the fixing section, and the elastic limiting column and the limiting block are configured to enable the second elastic piece to enter the fixing section from the access section and prevent the second elastic piece from returning to the access section from the fixing section. Further enabling the second elastic member to be firmly connected with the lumbar support member without screws.

Adopted above-mentioned technical scheme the utility model discloses a design departure point, theory and beneficial effect are:

the utility model has the advantages that:

1. the separated back support piece and the waist support piece are rotatably connected to the back bracket, so that the chair back component has better moving performance, can adapt to changeable waist and back curves of a human body and conforms to ergonomics; can rotate according to different body contours and waist-back curves, automatically adjust the state of the back support and the waist support: after the back support piece and the waist support piece rotate to form a curve which is concave backwards, the waist back of the human body is positioned between the back support piece and the waist support piece, namely, the waist support piece is positioned below the waist, so that the waist is effectively supported better, and the comfort is higher.

2. Different from the chair back component which rotates in the same direction on the market, the rotation directions of the back support piece and the waist support piece of the chair back component are different, and the waist support piece is not connected with the back support piece, so that the waist support piece cannot rise along with the rotation of the back support piece, and the condition that the waist support piece is separated from the waist of a human body cannot be generated; the curve formed by the rotation of the back support piece and the waist support piece can be fit with the waist and the back of a human body and better support the waist of the human body, and the comfort is better.

3. The combination of the X-shaped connecting part and the waist supporting part of the back supporting part and the arrangement of the skirt edges on the waist supporting part and the back supporting part enable the seat to be more attractive and attract the attention of potential customers.

Drawings

Fig. 1 is a schematic perspective view of the seat according to the embodiment of the present invention;

fig. 2 is a side view illustrating the rotation of the back support and the lumbar support according to the embodiment of the present invention;

fig. 3 is a front view of the seat in an embodiment of the invention;

fig. 4 is a schematic perspective view of the transition portion and the connecting portion according to the embodiment of the present invention;

fig. 5 is a schematic perspective view of a connecting portion according to an embodiment of the present invention;

fig. 6 is a front view of a connecting portion in an embodiment of the present invention;

fig. 7 is a schematic perspective view of a back support member according to an embodiment of the present invention;

fig. 8 is a schematic perspective view of a lumbar support according to an embodiment of the present invention;

fig. 9 is a schematic perspective view of the back support member, the waist support member, the back frame, and the first and second elastic pieces according to the embodiment of the present invention;

fig. 10 is a schematic perspective view of a first elastic sheet according to an embodiment of the present invention;

fig. 11 is a schematic perspective view of a second elastic piece according to an embodiment of the present invention;

fig. 12 is a schematic perspective view of the second elastic sheet mounted to the lumbar support member according to the embodiment of the present invention;

fig. 13 is a comparison view of the back support member and the lumbar support member before and after rotation according to the first embodiment of the present invention;

fig. 14 is a schematic perspective view of a back support, a waist support and a back frame according to a second embodiment of the present invention;

fig. 15 is a side view of the back support and the lumbar support of the second embodiment of the present invention mounted on the back frame.

The figures are numbered: a back support 1; a seat 2; an armrest 3; a lifting air rod 4; five-star feet 5; a back support 6; a first hollow portion 61; a first receptacle 62; a first upper cross bar 6 a; a first lower cross bar 6 b; a first vertical bar 6 c; a lumbar support 7; the second hollow portion 71; a second receptacle 72; a second upper cross bar 7 a; a second lower cross bar 7 b; a second vertical bar 7 c; a transition portion 8; a connecting portion 9; a first connecting arm 91; a second connecting arm 92; a fixing plate 10; a first rotating base 11; a second rotary base 12; a rotating shaft hole 13; a rotating shaft 14; a first elastic member 15; a first spring piece 15 a; a second elastic sheet 15 b; a confluent portion 15 c; a second elastic member 16; a limiting boss 17; a mounting groove 18; an access segment 18 a; a fixed section 18 b; an elastic stopper column 19; a stopper 20; a first shaft seat 21; a second spindle base 22.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention more clearly understood, the present invention will be described in further detail with reference to the accompanying drawings and detailed description. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.

In the description of the present invention, the term "at least one" means one or more unless explicitly defined otherwise. The terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

The specific implementation manner of the utility model is as follows:

example 1: as shown in fig. 1-13, the present invention provides an ergonomic chair, which comprises a back support 1 and a back assembly, as shown in fig. 1, the chair further comprises a chair seat 2 for supporting a human body to sit on, armrests 3 disposed on two sides of the chair seat 2, a lifting air rod 4 configured to adjust the height of the chair seat 2, and five star feet 5 disposed at the lower end of the lifting air rod 4; the back support 1 is configured to be directly or indirectly connected with the seat 2, in this embodiment, the back support 1 is rotatably connected with the seat 2 through a chassis, the chassis is fixedly installed at the bottom of the seat 2, and the upper end of the lifting air rod 4 is inserted into the chassis; the chair back component is arranged at the front side of the back bracket 1 and is configured to support the waist and the back of a human body.

As shown in fig. 1, the chair in this embodiment further includes a chair back assembly, a chair seat 2 for supporting a human body to sit on, armrests 3 disposed at two sides of the chair seat 2, a lifting air rod 4 configured to adjust the height of the chair seat 2, and five-star feet 5 disposed at the lower end of the lifting air rod 4; the back support 1 is configured to be directly or indirectly connected with the seat 2, in this embodiment, the back support 1 is rotatably connected with the seat 2 through a chassis, the chassis is fixedly installed at the bottom of the seat 2, and the upper end of the lifting air rod 4 is inserted into the chassis; the chair back component is arranged at the front side of the back support 1, the chair back component is configured to support the waist and back of a human body, and the waist support part 7 is one part of the chair back component.

Further, as shown in fig. 2 and 3, in order to enable the chair back assembly to reasonably support the waist and back of the human body, the chair back assembly adopts an upper-lower double-back structure: the chair back assembly further comprises a back support 6; the back support piece 6 and the waist support piece 7 are vertically separated and are respectively and rotatably connected to the back bracket 1, and the respective rotating axes of the back support piece 6 and the waist support piece 7 are arranged along the left and right direction of the chair; as shown in fig. 13, the separated back support member 6 and waist support member 7 are rotatably connected to the back frame 1, which makes the chair back assembly have better moving performance and can adapt to the variable lumbar and dorsal curves of the human body, and the lumbar and dorsal curves are generally backward curved, so that when the back support member 6 and the waist support member 7 rotate in response to the leaning force of the human body, the rotation directions of the back support member 6 and the waist support member 7 are opposite and form a backward concave curve fitting the lumbar and dorsal of the human body, i.e. as shown in fig. 2, the lower end of the back support member 6 rotates backward (counterclockwise rotation), the upper end of the waist support member 7 rotates backward (clockwise rotation), the lumbar and dorsal part of the human body is located between the back support member 6 and the waist support member 7, and the waist support member 7 is located below the lumbar part, thereby effectively and better supporting the lumbar part with high comfort; specifically, the method comprises the following steps:

the upper end of the back support piece 6 is rotationally connected with the upper end of the back bracket 1, and the lower end of the waist support piece 7 is rotationally connected with the back bracket 1; as shown in fig. 4-6, the back frame 1 includes a transition portion 8 and a substantially X-shaped connecting portion 9, the transition portion 8 is an L-shaped steel plate, and the transition portion 8 is configured to connect the chassis and the connecting portion 9; because the connecting portion 9 is X-shaped, the connecting portion 9 has two first connecting arms 91 extending upward and two second connecting arms 92 extending downward, i.e. the first connecting arms 91 are located at the upper side of the connecting portion 9, and the second connecting arms 92 are located at the lower side of the connecting portion 9; the waist support part is rotationally connected with the second connecting arm; a lower side fork is formed between the two lower second connecting arms 92, a fixing plate 10 is arranged in the lower side fork, the fixing plate 10 and the connecting part 9 are integrally formed, and the connecting part 9 and the transition part 8 are fixedly connected through the fixing plate 10; the front surfaces of the two upper first connecting arms 91 close to the end parts are provided with first rotating seats 11, the front surfaces of the two lower second connecting arms 92 close to the end parts are provided with second rotating seats 12, and the first rotating seats 11 and the second rotating seats 12 are provided with rotating shaft holes 13 which penetrate through the first rotating shafts 14 or the second rotating shafts 14 along the left-right direction; as shown in fig. 7 and 8, the back support member 6 and the waist support member 7 are both frame structures with skirt edges, and the skirt edges can hide the edges of the mesh fabric to make the seat more beautiful; the back support 6 has a first hollow portion 61, the waist support 7 has a second hollow portion 71, the back support 6 is provided with a first insertion hole 62 corresponding to the first rotating seat 11 and opening toward the first hollow portion 61, the waist support 7 is provided with a second insertion hole 72 corresponding to the second rotating seat 12 and opening toward the second hollow portion 71; the back support member 6 comprises a first upper cross bar 6a, a first lower cross bar 6b and two first vertical bars 6c connected with the ends of the first upper cross bar 6a and the first lower cross bar 6 b; the waist support part 7 comprises a second upper cross bar 7a, a second lower cross bar 7b and two second vertical bars 7c connected with the ends of the second upper cross bar 7a and the second lower cross bar 7 b; as shown in fig. 9, after the two first connecting arms 91 on the upper side of the rotating part enter the first hollow part 61, the end shapes of the two first connecting arms 91 are fitted with the shape of the joint of the first upper cross bar 6a and the first vertical bar 6c, and at this time, the rotating shaft hole 13 of the first rotating seat 11 is aligned with the first inserting hole 62 and is rotatably connected through a rotating shaft 14 inserted between the two; similarly, after the two second connecting arms 92 at the lower side of the rotating portion enter the second hollow portion 71, the end shapes of the two second connecting arms 92 are fitted with the shape of the joint of the second lower cross bar 7b and the second vertical bar 7c, and at this time, the rotating shaft hole 13 of the second rotating seat 12 is aligned with the second insertion hole 72 and is rotatably connected through a rotating shaft 14 inserted between the two.

In addition, as shown in fig. 1, 2 and 9, in order to enable the back support member 6 and the waist support member 7 to be reset after rotating, and have resilience capability at the same time, so as to be more fit with the waist and back of the human body, a first elastic member 15 is arranged between the back support member 6 and the back bracket 1, and the first elastic member is configured to act on the lower end of the back support member 6 and provide a resetting force for the back support member 6; a second elastic piece 16 is arranged between the waist support piece 7 and the back support 1, and the second elastic piece 16 is configured to act on the upper end of the waist support piece 7 and provide a resetting force for the waist support piece 7; as shown in fig. 10 and 11, the first elastic member 15 and the second elastic member 16 are plastic reset elastic sheets, the first elastic member 15 is in a V-shaped plate shape, the first elastic member 15 has a first elastic sheet 15a, a second elastic sheet 15b and a junction portion 15c, the first elastic sheet 15a and the second elastic sheet 15b have an included angle, and both are connected to the junction portion 15 c; the first insertion hole 62 is formed in the position, close to the upper end, of the first vertical rod 6 c; the first elastic sheet 15a and the second elastic sheet 15b are connected to the first connecting arm 91, and the junction part 15c is inserted into the first lower cross bar 6 b; the second elastic part 16 is in a slender strip shape and is vertically arranged between the waist support part 7 and the back support 1, and the second insertion hole 72 is formed in the position, close to the lower end, of the second vertical rod 7 c; the lower end of the second elastic member 16 is mounted on the back bracket 1, and the upper end of the second elastic member 16 is inserted into the second upper cross bar 7 a.

As shown in fig. 1, 11, and 12, two limiting bosses 17 are disposed at an upper end of the second elastic member 16 at intervals in the vertical direction, a mounting groove 18 is disposed on the second upper cross bar 7a, the mounting groove 18 is a vertically through long groove and includes an access section 18a and a fixed section 18b, a width of the fixed section 18b is smaller than a width of the access section 18a, the access section 18a is configured to avoid the limiting bosses 17, so that the second elastic member 16 enters the mounting groove 18, and the fixed section 18b is configured to prevent the second elastic member 16 from coming out of the mounting groove 18; the connection section 18a is further provided with an elastic limiting column 19, the end of the elastic limiting column 19 is provided with a limiting block 20, the limiting block 20 is located at the position where the connection section 18a is adjacent to the fixing section 18b, and the elastic limiting column 19 and the limiting block 20 are configured to enable the second elastic element 16 to enter the fixing section 18b from the connection section 18a and prevent the second elastic element 16 from returning to the connection section 18a from the fixing section 18 b.

Example 2: the difference between the embodiment and the embodiment 1 lies in the difference of the back support, and other parts are changed correspondingly to adapt to the back support.

As shown in fig. 14 and 15, the back support 1 is a column, the back support 1 is provided with a first rotating shaft seat 21 which is located at the upper part of the back support 1 and protrudes forward and a second rotating shaft seat 22 which is located at the lower part of the back support 1 and protrudes forward, the upper part of the back support 6 is rotatably connected to the first rotating shaft seat 21, and the lower part of the waist support 7 is rotatably connected to the second rotating shaft seat 22; a first upper cross bar 6a of the back support member 6 is provided with a first rotating seat 11 protruding downwards, a second lower cross bar 7b of the waist support member 7 is provided with a second rotating seat 12 (not shown), the first rotating seat 11 is rotatably connected with a first rotating shaft seat 21 through a rotating shaft (not shown), and the second rotating seat 12 is rotatably connected with a second rotating shaft seat 22 through a rotating shaft; the first elastic element 15 and the second elastic element 16 are both strip-shaped plastic return elastic pieces.

Claims

1. An ergonomic chair, comprising:

a back support configured to connect to a seat;

2. The ergonomic chair of claim 1 wherein: the upper end of the back support piece is rotationally connected with the back support, and the lower end of the waist support piece is rotationally connected with the back support.

3. The ergonomic chair of claim 2 wherein: the back bracket comprises a connecting part which is approximately X-shaped and is provided with two first connecting arms extending upwards and two second connecting arms extending downwards; the back support piece is rotatably connected with the first connecting arm, and the waist support piece is rotatably connected with the second connecting arm.

4. An ergonomic chair as claimed in claim 3, wherein: the front surface of the first connecting arm close to the end part is provided with a first rotating seat, the front surface of the second connecting arm close to the end part is provided with a second rotating seat, and the first rotating seat and the second rotating seat are both provided with rotating shaft holes which penetrate through the first rotating seat or the second rotating seat along the left-right direction; the back support piece and the waist support piece are both of a frame structure, the back support piece is provided with a first hollow part, the waist support piece is provided with a second hollow part, the back support piece is provided with a first jack corresponding to the first rotating seat and with an opening facing the first hollow part, and the waist support piece is provided with a second jack corresponding to the second rotating seat and with an opening facing the second hollow part; the two first connecting arms enter the first hollow part, and a rotating shaft hole of the first rotating seat is aligned with the first jack and is rotationally connected with the first jack through a rotating shaft inserted in the first rotating seat and the second rotating seat; and the two second connecting arms enter the second hollow part, and the rotating shaft hole of the second rotating seat is aligned with the second jack and is rotatably connected with the rotating shaft hole through the rotating shaft inserted in the second rotating seat.

5. The ergonomic chair of claim 4 wherein: the back support piece is of a frame structure and comprises a first upper cross rod, a first lower cross rod and two first vertical rods connected with the ends of the first upper cross rod and the first lower cross rod; the shape of the end part of the first connecting arm is fitted with the shape of the joint of the first lower cross rod and the first vertical rod; the waist support piece is of a frame structure and comprises a second upper cross rod, a second lower cross rod and two second vertical rods connected with the ends of the second upper cross rod and the second lower cross rod; the shape of the end part of the second connecting arm is attached to the shape of the joint of the second lower cross rod and the second vertical rod.

6. The ergonomic chair of claim 2 wherein: the back support is a stand column, a first rotating shaft seat which is located on the upper portion of the back support and protrudes forwards and a second rotating shaft seat which is located on the lower portion of the back support and protrudes forwards are arranged on the back support, the upper portion of the back support is rotatably connected to the first rotating shaft seat, and the lower portion of the waist support is rotatably connected to the second rotating shaft seat.

7. The ergonomic chair of claim 1 wherein: a first elastic piece is arranged between the back support piece and the back bracket, and the first elastic piece is configured to act on the lower end of the back support piece and provide resetting force for the back support piece; and a second elastic part is arranged between the waist support part and the back support, and the second elastic part is configured to act on the upper end of the waist support part and provide a resetting force for the waist support part.

8. The ergonomic chair of claim 7 wherein: the first elastic piece and the second elastic piece are plastic reset elastic pieces.

9. The ergonomic chair of claim 7 wherein: the second elastic piece is in a long and thin strip shape, and two spaced limiting bosses are arranged at the upper end of the second elastic piece; the waist support part is of a frame structure and comprises a second upper cross bar close to the back support part; the second upper cross rod is provided with a mounting groove, the mounting groove is a long groove which is communicated up and down and comprises an access section and a fixed section, the groove width of the fixed section is smaller than that of the access section, the access section is configured to avoid a limiting boss, so that the second elastic piece enters the mounting groove, and the fixed section is configured to prevent the second elastic piece from being separated from the mounting groove when the mounting groove is positioned between two limiting blocks.

10. The ergonomic chair of claim 9 wherein: the access section is further provided with an elastic limiting column, the end part of the elastic limiting column is provided with a limiting block, the limiting block is positioned at the position where the access section is adjacent to the fixed section, and the elastic limiting column and the limiting block are configured to enable the second elastic piece to enter the fixed section from the access section and prevent the second elastic piece from returning to the access section from the fixed section.