CN223653522U - seat - Google Patents

Abstract

The application discloses a seat which comprises a backrest, a seat, a base, a rotating support rod, a rear support and a seat, wherein the base comprises a seat support part and a backrest support part which are mutually hinged, the rotating support rod is arranged at the left side and the right side of the front end of the seat support part and comprises a short support rod and a long support rod which are mutually inclined and always kept relatively fixed, the intersection part of the lower ends of the short support rod and the long support rod is a rotating part, the rotating part is hinged to the seat support part, the upper end of the long support rod is hinged to the backrest, the upper end of the short support rod is hinged to the seat, the seat can slide up and down relative to the seat support part and drive the short support rod to rotate back and forth around the rotating part, the lower end of the rear support is hinged to the rear end of the backrest support part, and the upper end of the rear support is relatively connected with the backrest.

Description

Seat tool

Technical Field

The utility model relates to the technical field of seats, in particular to a seat capable of being switched among multiple modes.

Background

Today, people often need to sit for a long time to do work or study. In this period, if the sitting posture is not right, various diseases such as myopia, scoliosis, lumbar muscle strain and the like are easily caused, and the problems are particularly serious for teenagers who develop bodies. In order to keep a user in a good sitting posture, a back pushing chair appears in the prior market, and when the user sits on the back pushing chair, the back of the back pushing chair can automatically translate forward, so that the back of the user is stably supported, and the user is helped to correct the sitting posture.

For example, the present inventors' prior patent provides a seat support and a seat (publication number: CN 219661278U) comprising a four-bar mechanism of a base, a mounting bar, a support bar, a armrest, and a connection bar, wherein when the four-bar mechanism is operated, a connection block on the mounting bar is rotated forward/backward, a backrest mounting seat on the armrest is translated forward/backward along with the armrest, a seat link is driven to descend and move forward when the connection block is rotated forward, a seat link is driven to ascend and move backward when the connection block is rotated backward, and a backrest mounted on the backrest mounting seat is translated forward/backward along with the armrest, so that the backrest can be maintained at a correct support angle for a human body.

However, due to the guidance of the best effort, the development of the seat towards the direction of structure optimization finds the defects that the backrest can only keep the vertical posture to perform forward and backward translational movement in the use process, and if a user wants to lie back for rest after working or learning, the backrest cannot rotate backwards by a large angle to an angle suitable for the lying back of the user, so that the user cannot lie back on the seat for rest, the seat cannot meet the deeper requirements of the user, and the practicability is relatively insufficient.

Disclosure of Invention

In view of the above-mentioned drawbacks or shortcomings in the prior art, it is desirable to provide a seat, in which a backrest, a long strut, a rear bracket and a backrest support are hinged to each other to form a similar parallel four-bar structure, and the long strut drives the short strut to rotate and to link up and down the seat, so that the seat not only has an adaptive lumbar support state in which the backrest translates forward in response to sinking of the seat, but also has a self-negative tilting state in which the backrest is tilted backward and the seat is lifted upward in response to sinking of the seat, and thus, the seat can simultaneously meet the requirements of the user for adjusting the backrest and the pitching, and has good practicability.

The effect of the utility model is realized as follows:

The embodiment of the application provides a seat, which comprises:

a backrest configured to support a user's back;

a seat configured to support a user for sitting;

The base is of a split type structure and comprises a seat support part and a backrest support part which are spliced up and down, and the front end of the seat support part and the front end of the backrest support part are mutually hinged, so that the backrest support part can rotate up and down relative to the seat support part;

The rotating support rod is arranged at the left side and the right side of the front end of the seat support part, comprises a short support rod and a long support rod which are mutually inclined and always kept relatively fixed, the intersection part of the lower ends of the short support rod and the long support rod is a rotating part, and the rotating support rod is hinged to the seat support part through the rotating part so that the whole rotating support rod can synchronously rotate around the rotating part;

The lower end of the rear bracket is hinged to the rear end of the backrest supporting part, and the upper end of the rear bracket is connected with the backrest;

The seat is provided with a switchable initial state, a self-adaptive lumbar support state and a self-negative tilting state, when the seat is in the initial state, the seat is not pressed and is in a higher position, the backrest is not pressed by leaning force and keeps an upright state, when the seat is pressed and moves downwards in the initial state, the seat is switched to the self-adaptive lumbar support state, the short support rod and the long support rod are driven by the seat to swing forwards synchronously, the rear support rod responds to the long support rod to swing forwards synchronously, the backrest hinged to the upper sides of the long support rod and the rear support rod is driven to translate forwards and eject out, when the backrest is pressed by leaning force, the seat is switched to the self-negative tilting state, the backrest support part rotates downwards relative to the seat support part, the backrest responds to the backrest support part to rotate downwards synchronously, and the long support rod and the rear support rod rotate backwards synchronously, so that the backrest on the upper side can tilt backwards, and the short support rod and the long support rod swing backwards synchronously, and drive the seat to move upwards.

Further, in the self-adaptive lumbar support state, the movement distance of the backrest in the horizontal direction is 0-15cm, and in the self-load tilting state, the tilting angle of the backrest is 0-30 degrees. The self-adaptive lumbar support backrest has a long enough forward and backward sliding stroke to adapt to the seat depth of users with various body types, and has a large enough pitching angle to ensure that the users can rest in a comfortable lying posture in a self-load tilting state, so that the self-adaptive lumbar support backrest has good practicability.

Further, a locking device is arranged between the seat support part and the backrest support part, the locking device is provided with a switchable locking state and an unlocking state, when the seat is switched to the self-adaptive lumbar support state, the locking device is in the locking state, the seat support part and the backrest support part are relatively fixed, and when the seat is switched to the self-negative tilting state, the locking device is in the unlocking state, and the backrest support part can rotate relative to the seat support part again. The locking device is used for switching the locking state and the unlocking state, so that the switching operation of the seat between the initial state, the self-adaptive lumbar support state and the self-load tilting state can be realized, the adjusting operation is simple and convenient, the self-adaptive lumbar support state and the self-load tilting state are not interfered with each other, and the stability of the seat is good.

The front end of the seat support portion is provided with a first connecting portion, the front end of the backrest support portion is provided with a second connecting portion, the first connecting portion is hinged to the second connecting portion, the first connecting portion is provided with a first limiting hole in a left-right direction and a hollow-out mode, the second connecting portion is provided with a second limiting hole in a left-right direction and a hollow-out mode, the locking device comprises a locking pin which is connected with the first limiting hole and the second limiting hole in a sliding mode, in a locking state, the first limiting hole is communicated with the second limiting hole, the locking pin slides to be clamped in the first limiting hole and the second limiting hole at the same time, so that the second connecting portion cannot rotate relative to the first connecting portion, the seat support portion and the backrest support portion are relatively fixed, in an unlocking state, the locking pin slides to avoid the first limiting hole or the second limiting hole, and the backrest support portion can rotate relative to the seat support portion again. The locking device is adjusted to switch the locking state or the unlocking state by simultaneously clamping or avoiding the first limiting hole and the second limiting hole through the sliding adjustment locking pin, so that the locking device is simple and convenient to adjust and operate, and the locking device is simple in overall structure and easy to set.

The locking device further comprises an extrusion part, the extrusion part is arranged on one side of the rotation part close to the second connecting part, the rotation part rotates forwards in a self-adaptive lumbar support state, the extrusion part rotates inwards to enable the locking pin to slide inwards to be clamped in the first limiting hole and the second limiting hole at the same time, the locking device enters a locking state, the seat support part and the backrest support part are relatively fixed, the rotation part rotates backwards in a self-loading tilting state, the extrusion part rotates along with the rotation part and avoids the locking pin, the locking pin slides outwards to be separated from the first limiting hole, and the locking device enters an unlocking state, so that the backrest support part can rotate downwards relative to the seat support part again. When the seat is switched from the initial state to the self-adaptive lumbar support state or the self-loading tilting state, the locking device can automatically switch the locking state or the unlocking state along with the rotation of the rotating part, so that the convenience of the switching operation of the seat state is effectively improved.

Further, a first elastic piece is arranged in the second limiting hole, the first elastic piece acts on the locking pin, and the locking pin always has a trend of moving towards a direction away from the first connecting portion. When the seat is directly switched from the initial state to the self-load tilting state, the locking pin can automatically pop outwards by means of the elastic force of the first elastic piece and is separated from the first limiting hole, so that the locking device can be automatically switched to the unlocking state, and the simplicity of the switching operation of the seat state is further improved.

Further, the pressing portion is disposed near the end face of the locking pin and/or the end face of the locking pin near the pressing portion is disposed in an inclined manner, so that when the rotating portion drives the pressing portion to do circular motion and pushes the locking pin, the locking pin can slide towards the first connecting portion along the inclined direction of the end face. By arranging the end surfaces of the pressing portion and/or the locking pin close to each other obliquely, the structure is simple, and the circumferential rotation of the pressing portion can be converted into the sliding of the locking pin in the horizontal direction.

Further, a second elastic piece is arranged between the seat support portion and the backrest support portion, and two ends of the second elastic piece respectively act on the seat support portion and the backrest support portion, so that the backrest support portion always has a tendency of rotating towards the seat support portion. When the seat is switched from the self-load tilting state to the initial state, the backrest support part automatically rotates upwards under the elastic action of the second elastic piece, and then the backrest at the upper side is driven to return to the initial state, so that the simplicity of the switching operation of the seat state is improved.

The back support part comprises a back support part and a sliding part, wherein the back support part is formed by extending the back end backwards, the sliding part is connected to the back support part in a sliding way along the front-back direction, the bottom end of the back support is hinged to the sliding part, the sliding part is pressed by the back support and slides forwards in a self-load tilting state, the bottom end of the back support is driven by the sliding part to slide forwards, so that the top end of the back support rotates backwards, and the back hinged to the top end of the back support is driven to tilt backwards further. The backrest can be inclined backwards by a larger angle, so that a user can lie on the seat in a more comfortable posture, and the backrest rotates by a larger angle along with the lifting of the seat, so that the back of the user cannot be rubbed, and the use experience is more comfortable.

Further, a gear adjusting piece is fixedly connected to the sliding support portion, a gear adjusting mechanism is arranged between the sliding piece and the gear adjusting piece, the gear adjusting mechanism comprises a clamping head and a plurality of gear grooves, the clamping head is arranged on one of the sliding piece and the gear adjusting piece, the plurality of gear grooves are arranged on the other one of the sliding piece and the gear adjusting piece, and when the sliding piece slides back and forth relative to the gear adjusting piece, the clamping head is sequentially clamped and matched with the plurality of gear grooves. The sliding piece can be fixed at any position on the sliding supporting part, and then the backrest can realize adjustment and fixation of the pitching angle by means of the gear adjusting mechanism, so that the backrest is more convenient to use.

Further, the clamping head is movably connected to the gear adjusting piece, a plurality of gear grooves are correspondingly formed in the sliding piece, the gear adjusting mechanism is provided with a switchable fixing state and a sliding state, the clamping head outwards slides to be clamped in the gear grooves in the fixing state so that the sliding piece and the gear adjusting piece are relatively fixed, and the clamping head inwards slides into the retracted gear adjusting piece and avoids the gear grooves in the sliding state so that the sliding piece can slide again relative to the gear adjusting piece. The gear groove is clamped or avoided by means of the movement of the clamping head, so that the sliding piece and the sliding supporting part are movable or fixed, the operation is convenient, and the gear adjusting operation is simple and convenient.

Further, the sliding part is of a plate-shaped structure, a first sliding supporting groove extending along the front and back directions is formed in the sliding part in a hollowed-out mode, a gear adjusting part is connected to the sliding part in a sliding mode, a limiting part is formed in the gear adjusting part in a protruding mode, the limiting part penetrates through the first sliding supporting groove and is connected to the sliding supporting part, the sliding part is clamped between the sliding supporting part and the gear adjusting part, and the sliding part slides back and forth relative to the limiting part through the first sliding supporting groove. Not only the connection strength between the sliding piece and the sliding supporting part is higher, but also the sliding process of the sliding piece is smoother and more stable.

Further, the lower extreme of seat support is provided with two chassis connecting portions of bilateral symmetry, and two chassis connecting portions laminate in the left and right sides of seat support supporting part, connect through guiding mechanism between chassis connecting portion and the seat support supporting part, guiding mechanism includes mutually sliding fit's guide way and guide pin, and the guide way sets up in one of chassis connecting portion and seat support supporting part, and the guide pin sets up in the other one of chassis connecting portion and seat support supporting part. By means of the sliding of the guide pin in the guide groove, the chair seat slides up and down relative to the chair seat supporting part and is linked with the short supporting rod to rotate back and forth, the structure is simple, and the transmission process between the chair seat and the short supporting rod is smoother and more stable.

Further, the guide groove comprises a lumbar support guide part and a tilting guide part, wherein the lumbar support guide part and the tilting guide part are obliquely arranged, the inclination direction is from front to back and from low to high, and the inclination of the lumbar support guide part compared with the horizontal plane is larger than that of the tilting guide part. Through setting up the guide way slope for when the seat support slides from top to bottom, its position also can change in horizontal direction, and the gradient of propping up waist guiding portion is greater than leaning on the guiding portion, makes under the self-adaptation state of propping up waist, the change of seat support in horizontal direction is less, avoids influencing the seat depth and adjusts, under the self-weight state of leaning on, the seat support can remove longer distance in horizontal direction, thereby when adaptation back leans on, the position change of human buttock, the support experience is more comfortable.

Further, the short supporting rod is hinged to the front end of the chair seat, the chassis connecting portion is arranged at the rear end of the chair seat, and the guide groove is formed in the chassis connecting portion. The seat can be just above the base, the position is more reasonable, the guide groove is arranged on the chassis connecting part, the processing is easy, and the combination between the seat supporting part and the backrest supporting part can not be influenced.

Further, a third elastic piece is arranged between the seat and the seat supporting portion, in an initial state, the third elastic piece does not apply elastic force to the seat and the seat supporting portion, in a self-adaptive lumbar supporting state, the third elastic piece applies thrust to the seat and the seat supporting portion so that the seat has a trend of moving towards a direction away from the seat supporting portion, and in a self-loading tilting state, the third elastic piece applies tension to the seat and the seat supporting portion so that the seat has a trend of moving towards a direction approaching to the seat supporting portion. The seat can be automatically reset, and the rotating support rod, the backrest supporting part, the rear support and the backrest are driven by the seat to move, so that the seat is reset to an initial state, a user does not need to manually reset, and the convenience of the switching operation of the seat state is further improved.

Further, the third elastic piece is a controllable air spring, the seat support is connected with the third elastic piece through a wire control mechanism, the wire control mechanism comprises an adjusting switch and a pull rope connected between the adjusting switch and the third elastic piece, the adjusting switch is configured to adjust the pull rope to pull or release the thimble of the third elastic piece, and then the third elastic piece can be fixed on any telescopic length. The third elastic piece can be adjusted to stretch or fix only by pressing the adjusting switch, and the backrest is driven to move or fix, so that the adjusting operation is very simple and convenient.

According to the seat, the backrest, the long support rod, the rear support and the backrest support part are mutually hinged to form the similar parallel four-bar structure, the long support rod drives the short support rod to rotate and to link the seat to move up and down, so that the seat not only has a self-adaptive lumbar support state that the backrest moves forward in a translation mode in response to sinking of the seat, but also has a self-load tilting state that the backrest is tilted backwards and lifted upwards along with lifting of the seat, and can simultaneously meet the back-following adjustment requirement and the pitching adjustment requirement of a user, and the seat is good in practicability.

The back support can rotate downwards relative to the seat support in the unlocking state of the locking device, and then drives the upper backrest to rotate downwards, so that the switching operation of the seat between the initial state, the self-adaptive lumbar support state and the self-load tilting state can be realized by switching the locking state and the unlocking state of the locking device, the adjustment operation is simple and convenient, the back can not be pitching in the self-adaptive lumbar support state, the back can not be regulated in a back following mode, the pitching regulation of the back can not be influenced in the self-load tilting state, and the back can not be regulated in a forward translation mode, so that the pitching regulation of the back can not be influenced.

Drawings

Other features, objects and advantages of the present application will become more apparent upon reading of the detailed description of non-limiting embodiments, made with reference to the accompanying drawings in which:

fig. 1 is a schematic perspective view of a seat according to an embodiment of the present application;

Fig. 2 is a schematic view of a bottom structure of a seat according to an embodiment of the present application;

Fig. 3 is a schematic side view of a seat in an initial state according to an embodiment of the present application;

fig. 4 is a schematic side view of a seat in a self-adaptive lumbar support state according to an embodiment of the present application;

Fig. 5 is a schematic side view of a seat in a self-load tilting state according to an embodiment of the present application;

Fig. 6 is a schematic diagram of a changing process of the seat when the seat is changed from the initial state to the self-adaptive lumbar support state according to the embodiment of the present application;

Fig. 7 is a schematic diagram of a changing process of a seat when changing from an initial state to a self-negative tilting state according to an embodiment of the present application;

fig. 8 is a schematic cross-sectional view of a seat according to an embodiment of the present application;

FIG. 9 is a schematic view of a connection structure between a seat and a chassis according to an embodiment of the present application;

FIG. 10 is a schematic view of a connection structure between a seat support and a backrest support according to an embodiment of the present application;

Fig. 11 is a schematic cross-sectional structure of a chassis in an unlocked state according to an embodiment of the present application;

FIG. 12 is a schematic cross-sectional view of a chassis in a locked state according to an embodiment of the present application;

Fig. 13 is a schematic perspective view of a chassis and a rear bracket in a locked state according to an embodiment of the present application;

fig. 14 is a schematic perspective view of a chassis and a rear bracket in an unlocked state according to an embodiment of the present application;

FIG. 15 is a schematic view of a connection structure between a chassis and a rear bracket according to an embodiment of the present application;

FIG. 16 is a schematic view of an internal structure of a gear position adjusting mechanism according to an embodiment of the present application;

FIG. 17 is a schematic view of a connection structure between a gear position adjusting member and a sliding member in a fixed state according to an embodiment of the present application;

Fig. 18 is a schematic view of a connection structure between a gear adjusting member and a sliding member in a sliding state according to an embodiment of the present application.

The reference numerals are 1-back, 110-armrest, 120-armrest, 2-seat, 210-chassis connection, 211-guide slot, 211 a-lumbar support guide, 211 b-tilt guide, 220-third spring, 230-adjustment switch, 3-seat support, 301-guide pin, 310-first connection, 311-first limit hole, 320-transmission, 4-back support, 401-locking pin, 402-first spring, 403-second spring, 410-second connection, 411-second limit hole, 420-slide support, 430-slide, 431-shift slot, 432-first slide support slot, 433-second slide support slot, 440-shift adjustment, 441-clip, 442-limit, 443-receiving cavity, 444-torsion spring, 445-push-pull, 446-fourth spring, 5-turn bar, 510-short bar, 520-long bar, 510-turn, 531-push bar, and 6-push bar.

Detailed Description

The utility model is described in further detail below with reference to the drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the utility model and are not limiting of the utility model. It should be noted that, for convenience of description, only the portions related to the utility model are shown in the drawings.

Referring to fig. 1-18, an embodiment of the present application provides a seat, including:

A backrest 1 configured to support a user's back;

a seat 2 configured to support a user for sitting;

The base is of a split type structure and comprises a seat support part 3 and a backrest support part 4 which are spliced up and down, wherein the front end of the seat support part 3 and the front end of the backrest support part 4 are mutually hinged, so that the backrest support part 4 can rotate up and down relative to the seat support part 3;

The rotating support rod 5 is arranged at the left side and the right side of the front end of the seat support part 3, the rotating support rod 5 comprises a short support rod 510 and a long support rod 520 which are mutually inclined and always kept relatively fixed, the intersection part of the lower ends of the short support rod 510 and the long support rod 520 is a rotating part 530, the rotating support rod 5 is hinged to the seat support part 3 through the rotating part 530, so that the whole rotating support rod 5 can synchronously rotate around the rotating part 530, the upper end of the long support rod 520 is hinged to the backrest 1, the upper end of the short support rod 510 is hinged to the seat 2, and the seat 2 can slide up and down relative to the seat support part 3 and drives the short support rod 510 to rotate around the rotating part 530;

the lower end of the rear bracket 6 is hinged to the rear end of the backrest support part 4, and the upper end of the rear bracket 6 is connected with the backrest 1;

The seat has a switchable initial state, an adaptive lumbar support state and a self-negative tilting state, when the seat is in the initial state, the seat 2 is not pressed and is in a higher position, the backrest 1 is not pressed and keeps an upright state, when the seat 2 is pressed and moves downwards in the initial state, the seat is switched to the adaptive lumbar support state, the short support rod 510 and the long support rod 520 are synchronously swung forwards by the seat 2, the rear support 6 synchronously swings forwards in response to the long support rod 520, so that the backrest 1 hinged on the upper sides of the long support rod 520 and the rear support rod 6 is driven to translate forwards and eject, when the backrest 1 is pressed and leaned in the initial state, the seat is switched to the self-negative tilting state, the backrest support part 4 rotates downwards relative to the seat support part 3, the backrest 1 synchronously rotates downwards in response to the backrest support part 4, and the long support rod 520 and the rear support rod 6 synchronously rotate backwards, so that the backrest 1 on the upper side can tilt backwards, and the short support rod 510 and the long support rod 520 synchronously swings backwards, and drives the seat 2 to move upwards.

In this embodiment, the backrest 1, the long supporting rod 520, the rear support 6 and the backrest supporting part 4 are hinged to form a similar parallel four-bar structure, and the long supporting rod 520 drives the short supporting rod 510 to rotate and moves the seat 2 up and down, so that the seat not only has a self-adaptive lumbar support state in which the backrest 1 moves forward in a translation manner in response to the sinking of the seat 2, but also has a self-negative tilting state in which the backrest 1 is tilted backwards and the seat 2 is lifted upwards, thus the back-following adjustment requirement and the pitching adjustment requirement of a user can be met at the same time, and the practicability is good.

Preferably, the backrest 1 is formed with a handrail portion 110 extending forward at both left and right ends, and the top end of the long strut 520 is hinged to the handrail portion 110. The handrail portion 110 is along the sleeve-shaped structure that vertical direction fretwork set up, has all cup jointed handrail 120 about two handrail portions 110 for under self-adaptation corset state or from the heavy burden state of leaning on, handrail 120 can be along with back 1 together removal, make handrail 120 can remain in the position that supports the user hand all the time, need not to monotonously adjust, and use experience is comparatively comfortable convenient. Moreover, handrail 120 passes through handrail high mechanism sliding connection in handrail portion 110 for handrail 120 can slide height-adjusting from top to bottom, and the practicality is better, and the common mechanism in current seat is adopted to handrail high mechanism here, and this patent is not repeated in the description.

Referring to fig. 6 to 7, in some embodiments of the present application, the backrest 1 moves in the horizontal direction by a distance of 0 to 15cm in the self-adaptive lumbar support state, and the backrest 1 tilts by an angle of 0 to 30 ° in the self-load tilting state. The self-adaptive lumbar support backrest 1 has a long enough forward and backward sliding stroke to adapt to the seat depth of users of various sizes, and has a large enough pitching angle to ensure that the users can rest in a comfortable lying posture in a self-load tilting state, so that the self-adaptive lumbar support backrest has good practicability.

Referring to fig. 9-12, in some embodiments of the present application, a locking device is disposed between the seat support 3 and the backrest support 4, the locking device has a locking state and an unlocking state, when the seat is switched to the adaptive lumbar support state, the locking device is in the locking state, the seat support 3 and the backrest support 4 are relatively fixed, and when the seat is switched to the self-load tilting state, the locking device is in the unlocking state, and the backrest support 4 can rotate again relative to the seat support 3.

In this embodiment, the seat support 3 and the backrest support 4 are locked or moved by the locking device, in the locked state of the locking device, the long strut 520 and the rear bracket 6 can only swing back and forth to drive the backrest 1 to translate back and forth, in the unlocked state of the locking device, the backrest support 4 can rotate downward relative to the seat support 3 to drive the upper backrest 1 to rotate downward together, thereby, by switching the locked state and the unlocked state of the locking device, the switching operation of the seat between the initial state, the self-adaptive lumbar support state and the self-load lumbar support state can be realized, the adjusting operation is simple and convenient, in the self-adaptive lumbar support state, the backrest 1 cannot be pitching, the back following adjustment of the backrest 1 cannot be influenced, in the same way, the backrest 1 cannot be adjusted in a forward translation manner in the self-load lumbar support state, the self-load lumbar support state and the self-load lumbar support state cannot interfere with each other, and the stability of the seat is better.

Of course, in other embodiments of the present application, the locking device is not required between the seat support 3 and the backrest support 4, and the user applies pressure to one of the seat 2 and the backrest 1 to switch the seat between the initial state, the self-adaptive lumbar support state and the self-negative tilting state, so that no further locking operation is required, and the adjustment operation is simpler.

Referring to fig. 9-12, in some embodiments of the present application, a first connecting portion 310 is disposed at a front end of a seat support portion 3, a second connecting portion 410 is disposed at a front end of a backrest support portion 4, the first connecting portion 310 is hinged to the second connecting portion 410, a first limiting hole 311 is disposed on the first connecting portion 310 along a left-right direction hollow, a second limiting hole 411 is disposed on the second connecting portion 410 along a left-right direction hollow, the locking device includes a locking pin 401, the locking pin 401 is slidably connected to the first limiting hole 311 and the second limiting hole 411, in a locked state, the first limiting hole 311 is communicated with the second limiting hole 411, the locking pin 401 is slidably clamped in the first limiting hole 311 and the second limiting hole 411 at the same time, so that the second connecting portion 410 cannot rotate relative to the first connecting portion 310, the seat support portion 3 and the backrest support portion 4 are relatively fixed, in an unlocked state, the locking pin 401 is slidably connected to the first limiting hole 311 or the second limiting hole 411, and the backrest support portion 4 can rotate relative to the seat support portion 3 again.

In this embodiment, the locking device is adjusted to switch the locking state or the unlocking state by sliding the adjusting locking pin 401 to simultaneously clamp or avoid the first limiting hole 311 and the second limiting hole 411, so that the adjusting operation is simple, the whole structure is simple, and the setting is easy.

Wherein, back supporting part 4 and seat support supporting part 3 are half open box structure, and under the locking state, seat support supporting part 3 and back supporting part 4 are closed each other and form a complete base for the structure of base is compacter, and back supporting part 4 can rotate great angle for seat support supporting part 3.

Referring to fig. 9-12, in some embodiments of the present application, the front end of the backrest support 4 is provided with two second connecting portions 410 that are symmetrical left and right, the two second connecting portions 410 are hinged to the left and right sides of the first connecting portion 310, the rotating portions 530 on both sides are hinged to the two second connecting portions 410 respectively, the locking device further includes a pressing portion 531, the pressing portion 531 is disposed on one side of the rotating portion 530 near the second connecting portion 410, in the self-adaptive lumbar supporting state, the rotating portion 530 rotates forward, the pressing portion 531 rotates along with the pressing portion 531 and pushes the locking pin 401 inward, so that the locking pin 401 slides inward to be simultaneously clamped in the first limiting hole 311 and the second limiting hole 411, the locking device enters a locking state, the seat support 3 and the backrest support 4 are relatively fixed, in the self-loading tilt state, the rotating portion 530 rotates backward, the pressing portion 531 rotates along with the pressing portion and dodges the locking pin 401 so that the locking pin 401 slides outward to be separated from the first limiting hole 311, and the locking device enters an unlocking state, so that the backrest support 4 can slide downward relative to the seat support 3.

In this embodiment, by providing the pressing portion 531 on the rotating portion 530, the pressing portion 531 performs a circular motion along with the rotation of the rotating portion 530 and pushes or avoids the locking pin 401, so that when the seat is switched from the initial state to the self-adaptive lumbar support state or the self-weight-bearing tilting state, the locking device can automatically switch the locking state or the unlocking state along with the rotation of the rotating portion 530, and manual adjustment by a user is not required, thereby effectively improving the convenience of the switching operation of the seat state. And, the front end of back supporting part 4 is provided with two bilateral symmetry's second connecting portion 410, and two rotation portion 530 are connected in the second connecting portion 410 of both sides respectively for spacing through two sets of locking pin 401 between seat support portion 3 and the back supporting part 4, and along with the rotation of the rotation branch 5 of seat both sides, two sets of locking pin 401 are driven simultaneously and slide, make the locking or the unlocking operation between seat support portion 3 and the back supporting part 4 more steady.

Referring to fig. 11-12, in some embodiments of the present application, a first elastic member 402 is disposed in the second limiting hole 411, and the first elastic member 402 acts on the locking pin 401 and keeps the locking pin 401 moving away from the first connecting portion 310.

In this embodiment, when the seat is directly switched from the initial state to the self-load tilting state, when the rotating portion 530 rotates to the pressing portion 531 to avoid the locking pin 401, the locking pin 401 can automatically pop out by means of the elastic force of the first elastic member 402 and disengage from the first limiting hole 311, so that the locking device can be automatically switched to the unlocking state, the seat can automatically enter the self-adaptive lumbar support state, and the simplicity of the switching operation of the seat state is further improved.

Preferably, the first elastic member 402 is a spring, the locking pin 401 is integrally in a T-shaped structure, a side with a larger width of the locking pin 401 is close to the extruding portion 531, and the spring is sleeved on a slender side of the locking pin 401 and extrudes the locking pin 401 outwards, so that the locking pin is simple in structure and easy to set.

Referring to fig. 9-10, in some embodiments of the present application, the pressing portion 531 is near the end surface of the locking pin 401 and/or the end surface of the locking pin 401 near the pressing portion 531 is inclined, so that when the rotating portion 530 drives the pressing portion 531 to perform a circular motion and push the locking pin 401, the locking pin 401 can slide towards the first connecting portion 310 along the inclined direction of the end surface.

In the present embodiment, by disposing the end surfaces of the pressing portion 531 and/or the locking pin 401 close to each other obliquely, the structure is simple, and conversion of the circumferential rotation of the pressing portion 531 into the sliding of the locking pin 401 in the horizontal direction can be achieved.

Wherein, preferably, the end surface of the pressing part 531 near the locking pin 401 and the end surface of the locking pin 401 near the pressing part 531 are both inclined, so that the transmission between the two is smoother.

Referring to fig. 10, in some embodiments of the present application, a second elastic member 403 is disposed between the seat support portion 3 and the backrest support portion 4, and two ends of the second elastic member 403 respectively act on the seat support portion 3 and the backrest support portion 4, so that the backrest support portion 4 always has a tendency to rotate towards the seat support portion 3.

In this embodiment, by providing the second elastic member 403 between the seat support portion 3 and the backrest support portion 4, when the seat is switched from the self-load tilting state to the initial state, the backrest support portion 4 automatically rotates upwards under the elastic force of the second elastic member 403, and further drives the upper backrest 1 to rotate forwards to return to the vertical state, so that the seat is reset to the initial state, and a user does not need to manually rotate the backrest 1 to reset, thereby improving the convenience of the switching operation of the seat state.

Referring to fig. 13 to 14, in some embodiments of the present application, the back support 4 includes a sliding support 420 having a rear end extending rearward and a sliding member 430 slidably connected to the sliding support 420 in a front-rear direction, the bottom end of the rear bracket 6 is hinged to the sliding member 430, and in a self-load tilting state, the sliding member 430 receives pressure from the rear bracket 6 and slides forward, the bottom end of the rear bracket 6 is driven by the sliding member 430 and slides forward, so that the top end of the rear bracket 6 rotates rearward and drives the back 1 hinged to the top end of the rear bracket 6 to tilt rearward further.

In this embodiment, if the backrest 1 is driven to recline only by the rotation of the backrest support 4, the backrest 1 cannot lie on the seat due to the smaller rotatable angle of the backrest support 4, which cannot meet the requirement, and the backrest 1 cannot rub the back of the user due to the lifting of the backrest 2 when the backrest 1 cannot rotate by a larger angle during the tilting of the backrest 1 due to the synchronous upward movement of the seat 2 along with the reclining of the backrest 1, which is bad in use experience. Therefore, the bottom end of the rear bracket 6 is hinged to the sliding piece 430 capable of sliding back and forth, so that in a self-loading tilting state, besides the backrest 1 is driven to tilt backward by means of the rotation of the backrest supporting part 4, the rear bracket 6 rotates backward along with the forward movement of the sliding piece 430, the backrest 1 on the upper side is driven to tilt backward further, the backrest 1 can tilt backward by a larger angle, a user can lie on the seat in a more comfortable posture, and the backrest 1 rotates by a larger angle along with the lifting of the seat 2, so that the back of the user cannot be rubbed, and the use experience is more comfortable.

Wherein, a transmission member 320 is further connected between the seat support 3 and the sliding member 430, the front end of the transmission member 320 is hinged to the rear end of the seat support 3, and the rear end of the transmission member 320 is hinged to the sliding member 430. The combination of the seat support 3, the backrest support 4, the sliding member 430 and the transmission member 320 forms a structure similar to a three-link-one-chute structure, when the backrest support 4 rotates downward, the sliding member 430 is constrained by the transmission member 320 to be forced to slide forward, and when the backrest support 4 rotates upward, the sliding member 430 is constrained by the transmission member 320 to be forced to slide backward. Thus, the movement of the slider 430 is further restricted by the driving member 320, so that the movement process of the slider 430 is smoother.

Referring to fig. 15-18, in some embodiments of the present application, a gear adjusting member 440 is fixedly connected to a sliding support portion 420, a gear adjusting mechanism is disposed between a sliding member 430 and the gear adjusting member 440, the gear adjusting mechanism includes a chuck 441 and a plurality of gear slots 431, the chuck 441 is disposed on one of the sliding member 430 and the gear adjusting member 440, the plurality of gear slots 431 are disposed on the other of the sliding member 430 and the gear adjusting member 440, and the chuck 441 is sequentially engaged with the plurality of gear slots 431 when the sliding member 430 slides back and forth relative to the gear adjusting member 440.

In this embodiment, the sliding member 430 and the gear adjusting member 440 perform gear adjustment through the chuck 441 and the gear groove 431, so that the sliding member 430 can be fixed at any position on the sliding support portion 420, and further the backrest 1 can realize adjustment and fixation of the pitch angle by means of the gear adjusting mechanism, which is more convenient to use.

Referring to fig. 15-18, in some embodiments of the present application, a chuck 441 is movably connected to a gear adjusting member 440, a plurality of gear slots 431 are correspondingly provided on a sliding member 430, and the gear adjusting mechanism has a switchable fixing state and a sliding state, in the fixing state, the chuck 441 slides outwards to be clamped in the gear slots 431 so as to relatively fix the sliding member 430 and the gear adjusting member 440, and in the sliding state, the chuck 441 slides inwards to retract into the gear adjusting member 440 and to avoid the gear slots 431 so as to enable the sliding member 430 to slide again relative to the gear adjusting member 440.

In this embodiment, the chuck 441 is movably disposed on the gear adjusting member 440, and the gear groove 431 is clamped or avoided by the movement of the chuck 441, so that the sliding member 430 and the sliding support 420 are movable or fixed, and are convenient to operate, so that the gear adjusting operation is relatively simple.

Referring to fig. 17-18, the sliding member 430 is in a plate structure, the bottom end of the sliding member 430 is recessed upward to form a second sliding supporting groove 433 extending along the length direction, the gear adjusting member 440 is disposed in the second sliding supporting groove 433, and the sliding member 430 slides back and forth relative to the gear adjusting member 440 through the second sliding supporting groove 433, so that the connection strength between the two is better, and the sliding process is more stable. The left and right sides of the gear adjusting member 440 are provided with clamping heads 441, and the left and right side groove walls of the second sliding supporting groove 443 are correspondingly provided with gear grooves 431. The gear adjusting member 440 has a hollow structure and comprises an inner accommodating cavity 443, wherein one end of each of the left and right clamping heads 441 passes through the side wall of the gear adjusting member 440 and extends into the accommodating cavity 443, two bilaterally symmetrical torsion springs 444 are arranged in the accommodating cavity 443, one side arm of each of the two torsion springs 444 is respectively connected with the clamping heads 441 on the two sides, the other side arm of each of the two torsion springs 441 is connected with the push-pull member 445, and the push-pull member 445 can slide back and forth in the accommodating cavity 443 and drive the torsion springs 444 to pull or push the clamping heads 441 inwards. The seat 2 is further provided with a wire control mechanism, which comprises an adjusting switch 230 and a pull rope, wherein the adjusting switch 230 and the pull rope are arranged on the seat 2, one end of the pull rope is connected to the adjusting switch 230, the other end of the pull rope passes through the gear adjusting member 440 and is connected to the push-pull member 445, when the adjusting switch 230 is opened, the pull rope pulls the push-pull member 445 to slide forwards and drives the torsion spring 444 to pull the clamping head 441 inwards, so that the sliding member 430 can slide again relative to the gear adjusting member 440, the rear end of the push-pull member 445 is also connected with a fourth elastic member 446, the fourth elastic member 446 always pulls the push-pull member 445, so that the push-pull member 445 always has a tendency of sliding backwards, and further, when the adjusting switch 230 is closed, the pull rope releases the push-pull member 445 to automatically slide backwards under the elastic force of the fourth elastic member 446 and drives the torsion spring 444 to push the clamping head 441 outwards, so that the clamping head 441 is clamped into the gear groove 431 again, and the sliding member 430 is fixed on the gear adjusting member 440 again. Therefore, the locking and unlocking of the gear adjusting mechanism can be controlled by means of the wire control mechanism, and the operation is simple and convenient.

Preferably, the sliding member 430 is provided with four gear grooves 431 along the length direction, so that the gear adjusting mechanism has four adjustable gears with high degree of freedom of adjustment. Of course, in other embodiments of the present application, the number of the gear slots 431 on the sliding part 430 may be three, five, six, etc.

Referring to fig. 15, in some embodiments of the present application, the sliding member 430 is in a plate structure, a first sliding supporting groove 432 extending along a front-back direction is hollowed out on the sliding member 430, a gear adjusting member 440 is slidably connected to the sliding member 430, a limiting portion 442 is formed on the gear adjusting member 440 in a protruding manner, the limiting portion 442 passes through the first sliding supporting groove 432 and is connected to the sliding supporting portion 420, so that the sliding member 430 is clamped between the sliding supporting portion 420 and the gear adjusting member 440, and the sliding member 430 slides back and forth relative to the limiting portion 442 through the first sliding supporting groove 432.

In the present embodiment, the sliding member 430 is clamped by the sliding support portion 420 and the shift position adjusting member 440, and the sliding distance of the sliding member 430 is restricted by the stopper portion 442 and the first sliding support groove 432, so that not only the connection strength between the sliding member 430 and the sliding support portion 420 is higher, but also the sliding process of the sliding member 430 is smoother.

Preferably, two limiting portions 442 are formed on the gear adjusting member 440 in a protruding manner, two first sliding supporting grooves 432 are correspondingly hollowed out on the sliding member 430, and the connection strength between the sliding member 430 and the gear adjusting member 440 is further improved. After the limiting portion 442 passes through the first sliding supporting groove 432, the gear adjusting member 440 and the sliding supporting portion 420 are fixed by means of screw connection, so that the sliding member 430, the gear adjusting member 440 and the sliding supporting portion 420 are detachably arranged with each other, and the chassis is convenient to mount and dismount.

Referring to fig. 2-4, in some embodiments of the present application, two chassis connecting portions 210 are disposed at the lower end of the seat 2, the two chassis connecting portions 210 are attached to the left and right sides of the seat support portion 3, the chassis connecting portions 210 and the seat support portion 3 are connected by a guiding mechanism, the guiding mechanism includes a guiding slot 211 and a guiding pin 301 that are slidably matched with each other, the guiding slot 211 is disposed in one of the chassis connecting portion 210 and the seat support portion 3, and the guiding pin 301 is disposed in the other of the chassis connecting portion 210 and the seat support portion 3.

In this embodiment, by providing a guiding structure between the chassis connecting portion 210 and the seat support portion 3, a structure similar to a three-link-one chute is formed among the seat 2, the short strut 510, the seat support portion 3 and the guiding slot 211, and by sliding the guide pin 301 in the guiding slot 211, the seat 2 slides up and down relative to the seat support portion 3 and links the short strut 510 to rotate back and forth, so that the structure is simple and the transmission process between the seat 2 and the short strut 510 is smoother.

Of course, in other embodiments of the present application, the seat 2, the short strut 510 and the seat support 3 may be driven by other mechanisms, for example, another auxiliary strut is hinged between the seat 2 and the seat support 3, so that a four-bar mechanism is formed between the auxiliary strut, the seat 2, the short strut 510 and the seat support 3, and the short strut 510 and the auxiliary strut can be driven to rotate back and forth when the seat 2 slides up and down relative to the seat support 3.

Referring to fig. 2-4, in some embodiments of the present application, the guide groove 211 includes a lumbar support guide portion 211a and a tilt guide portion 211b, wherein the lumbar support guide portion 211a and the tilt guide portion 211b are both inclined in a front-to-back direction and a lower-to-higher direction, and the inclination of the lumbar support guide portion 211a relative to the horizontal plane is greater than that of the tilt guide portion 211b.

In this embodiment, the guide groove 211 is obliquely arranged, so that when the seat 2 slides up and down, the position of the seat 2 in the horizontal direction also changes, and the inclination of the lumbar support guide portion 211a is larger than that of the tilting guide portion 211b, so that the change of the seat 2 in the horizontal direction is smaller in the self-adaptive lumbar support state, the influence on the seat depth adjustment is avoided, and the seat 2 moves a longer distance in the horizontal direction in the self-load tilting state, thereby adapting to the position change of the buttocks of the human body when the backrest 1 tilts backward, and the support experience is more comfortable.

Referring to fig. 1-2, in some embodiments of the present application, a short strut 510 is hinged to the front end of the seat 2, a chassis connection portion 210 is disposed at the rear end of the seat 2, and a guiding slot 211 is formed in the chassis connection portion 210.

In this embodiment, the rotating strut 5 is hinged to the front side of the base, the short strut 510 is hinged to the front end of the seat 2, and the chassis connecting portion 210 is disposed at the rear end of the seat 2, so that the seat 2 can be located right above the base, and the position is more reasonable.

In other embodiments of the present application, if the rotating strut 5 is connected to the rear side of the base, the short strut 510 may be hinged to the rear end of the seat 2, and the chassis connection portion 210 is disposed at the front end of the seat 2. The guide groove 211 may be formed in the seat support portion 3.

Referring to fig. 8-9, in some embodiments of the present application, a third elastic member 220 is disposed between the seat 2 and the seat support 3, in an initial state, the third elastic member 220 does not apply elastic force to the seat 2 and the seat support 3, in an adaptive lumbar support state, the third elastic member 220 applies thrust to the seat 2 and the seat support 3 so that the seat 2 has a tendency to move away from the seat support 3, and in a self-load tilting state, the third elastic member 220 applies tension to the seat 2 and the seat support 3 so that the seat 2 has a tendency to move toward the seat support 3. When the user does not need to use the seat or needs to switch the state again, the seat 2 can be automatically reset by the elastic force of the third elastic member 220, and the rotating strut 5, the backrest supporting portion 4, the rear bracket 6 and the backrest 1 are moved by the driving of the seat 2, so that the seat is reset to the initial state, the user does not need to manually reset, and the convenience of the switching operation of the seat state is further improved.

Referring to fig. 1-8, in some embodiments of the present application, the third elastic member 220 is a controllable air spring, the seat 2 and the third elastic member 220 are connected by a wire control mechanism, the wire control mechanism includes an adjusting switch 230 and a pull rope connected between the adjusting switch 230 and the third elastic member 220, and the adjusting switch 230 is configured to adjust the pull rope to pull or release the ejector pin of the third elastic member 220, so that the third elastic member 220 can be fixed at any telescopic length.

In this embodiment, by using the controllable air spring, not only the elastic force can be applied to the seat 2, but also the seat 2 can be fixed at any telescopic length, so that the position of the seat 2 is fixed, the short strut 510 is also limited by the seat 2 and cannot rotate, and further the long strut 520 is driven to be fixed, so that the front and rear positions of the backrest 1 are fixed. In addition, the third elastic member 220 is controlled by the wire control mechanism, and the third elastic member 220 can be adjusted to stretch or fix only by pressing the adjusting switch 230, so that the adjusting operation is very simple and convenient.

The adjusting switch 230 controls the third elastic member 220, and controls the push-pull member 445 in the gear adjusting member 440, so that after the adjusting switch 230 is turned on, the third elastic member 220 can be retracted, the backrest 1 can translate forward and backward, the push-pull member 445 pulls the torsion spring 444 downward and drives the chuck 441 to retract, the sliding member 430 can slide forward and backward and drive the backrest 1 to adjust the recline angle, so that the backrest 1 can be movably adjusted as a whole, after the adjusting switch 230 is turned on, the length of the third elastic member 220 is fixed, the front and rear positions of the backrest 1 are fixed, and the push-pull member 445 releases the torsion spring 444 and drives the chuck 441 to pop out, the position of the sliding member 430 is fixed, and the backrest 1 cannot be rotationally adjusted to adjust the recline angle, so that the backrest 1 is kept fixed as a whole. Thus, by pressing the adjustment switch 230, the fixation or movement of the entire backrest 1 can be controlled, and the ease of the adjustment operation of the seat can be further improved.

Claims (17)

1. A seating furniture, comprising:

A backrest (1) configured to support a user's back;

a seat (2) configured to support a user for sitting;

The seat is of a split type structure and comprises a seat support part (3) and a backrest support part (4) which are spliced up and down, wherein the front end of the seat support part (3) and the front end of the backrest support part (4) are mutually hinged, so that the backrest support part (4) can rotate up and down relative to the seat support part (3);

The rotating support rod (5) is arranged at the left side and the right side of the front end of the seat support part (3), the rotating support rod (5) comprises a short support rod (510) and a long support rod (520) which are mutually inclined and always kept relatively fixed, the intersection part of the lower ends of the short support rod (510) and the long support rod (520) is a rotating part (530), the rotating support rod (5) is hinged to the seat support part (3) through the rotating part (530) so that the rotating support rod (5) can synchronously rotate around the rotating part (530), the upper end of the long support rod (520) is hinged to the backrest (1), the upper end of the short support rod (510) is hinged to the seat (2), and the seat (2) can slide up and down relative to the seat support part (3) and drives the short support rod (510) to rotate around the rotating part (530) forwards and backwards;

the lower end of the rear bracket (6) is hinged to the rear end of the backrest support part (4), and the upper end of the rear bracket (6) is relatively connected with the backrest (1);

The seat is provided with a switchable initial state, an adaptive lumbar support state and a self-load tilting state, when the seat is in the initial state, the seat (2) is not pressed and is positioned at a higher position, the backrest (1) is not pressed and keeps an upright state, when the seat (2) is pressed to move downwards in the initial state, the seat is switched to the adaptive lumbar support state, the short support rod (510) and the long support rod (520) are driven to synchronously swing forwards by the seat (2), the rear support frame (6) is synchronously swung forwards in response to the long support rod (520), the backrest (1) hinged to the upper sides of the long support rod (520) and the rear support frame (6) is driven to horizontally move forwards and push out, when the backrest (1) is pressed and is moved downwards in the initial state, the backrest support part (4) is switched to the self-load tilting state, the backrest support part (4) is rotated downwards relative to the seat support part (3), the backrest (1) is synchronously swung backwards in response to the long support rod (520) and the backrest (1) is synchronously swung backwards, and the backrest (2) is synchronously swung upwards.

2. The seat according to claim 1, wherein the backrest (1) has a moving distance of 0-15cm in the horizontal direction in the self-adaptive lumbar support state, and the backrest (1) has a tilting angle of 0-30 ° in the self-loaded tilt state.

3. The seat according to claim 1, characterized in that a locking device is arranged between the seat support (3) and the backrest support (4), the locking device has a switchable locking state and an unlocking state, the locking device is in the locking state when the seat is switched to the self-adaptive lumbar support state, the seat support (3) and the backrest support (4) are relatively fixed, the locking device is in the unlocking state when the seat is switched to the self-negative tilting state, and the backrest support (4) can rotate again relative to the seat support (3).

4. A seat according to claim 3, wherein the front end of the seat support (3) is provided with a first connection portion (310), the front end of the backrest support (4) is provided with a second connection portion (410), the first connection portion (310) is hinged to the second connection portion (410), the first connection portion (310) is provided with a first limit hole (311) along the left-right direction, the second connection portion (410) is provided with a second limit hole (411) along the left-right direction, the locking device comprises a locking pin (401), the locking pin (401) is slidably connected to the first limit hole (311) and the second limit hole (411), in a locked state, the first limit hole (311) is communicated with the second limit hole (411), the locking pin (401) is slidably clamped in the first limit hole (311) and the second limit hole (411) at the same time, so that the second connection portion (410) is provided with a second limit hole (411) along the left-right direction, and the second connection portion (410) can not rotate relative to the first connection portion (311) and the backrest support (4) in an unlocked state, and the backrest support (3) can not rotate relative to the first connection portion (311).

5. The seat according to claim 4, wherein the front end of the back support portion (4) is provided with two second connecting portions (410) which are bilaterally symmetrical, the two second connecting portions (410) are hinged on the left and right sides of the first connecting portion (310), the rotating portions (530) on the two sides are respectively hinged on the two second connecting portions (410), the locking device further comprises a pressing portion (531), the pressing portion (531) is arranged on one side, close to the second connecting portion (410), of the rotating portion (530), in an adaptive lumbar supporting state, the rotating portion (530) rotates forwards, the pressing portion (531) rotates along with the rotating portion and pushes the locking pin (401) inwards, so that the locking pin (401) slides inwards to be simultaneously clamped in the first limiting hole (311) and the second limiting hole (411), the seat support portion (3) and the back support portion (4) are respectively hinged on the two second connecting portions (410), the pressing portion (531) is arranged on one side, close to the second connecting portion (410), in an adaptive lumbar supporting state, the rotating portion (530) rotates forwards, and the locking pin (401) is pushed inwards, and the locking pin (401) is pushed downwards relative to the seat support portion (401) to the rotating portion (3) to the locking pin (401) to the rotating portion, and the locking pin (401) is released from the rotating portion (401).

6. The seat according to claim 5, characterized in that a first elastic member (402) is provided in the second limiting hole (411), the first elastic member (402) acting on the locking pin (401) and causing the locking pin (401) to always have a tendency to move in a direction away from the first connecting portion (310).

7. The seat according to claim 5, wherein the pressing portion (531) is disposed near an end face of the locking pin (401) and/or the locking pin (401) is disposed near an end face of the pressing portion (531) in an inclined manner, so that the locking pin (401) can slide toward the first connecting portion (310) in an inclined direction of the end face when the pressing portion (531) is driven by the rotating portion (530) to perform a circular motion and push the locking pin (401).

8. A seat according to claim 1, characterized in that a second elastic element (403) is arranged between the seat support (3) and the backrest support (4), the two ends of the second elastic element (403) acting on the seat support (3) and the backrest support (4), respectively, so that the backrest support (4) always has a tendency to rotate towards the seat support (3).

9. The seat according to claim 1, wherein the back support portion (4) includes a sliding support portion (420) formed by rearward extension of a rear end thereof and a slider (430) slidably connected to the sliding support portion (420) in a front-rear direction, a bottom end of the rear bracket (6) is hinged to the slider (430), the slider (430) receives pressure from the rear bracket (6) and slides forward in a load tilting state, and a bottom end of the rear bracket (6) is driven by the slider (430) and slides forward so that a top end of the rear bracket (6) rotates rearward and drives the backrest (1) hinged to the top end of the rear bracket (6) to tilt further rearward.

10. The seat according to claim 9, wherein a gear adjusting member (440) is fixedly connected to the sliding support portion (420), a gear adjusting mechanism is arranged between the sliding member (430) and the gear adjusting member (440), the gear adjusting mechanism comprises a clamping head (441) and a plurality of gear grooves (431), the clamping head (441) is arranged on one of the sliding member (430) and the gear adjusting member (440), the plurality of gear grooves (431) are arranged on the other of the sliding member (430) and the gear adjusting member (440), and when the sliding member (430) slides back and forth relative to the gear adjusting member (440), the clamping head (441) is sequentially in clamping fit with the plurality of gear grooves (431).

11. The seat according to claim 10, wherein the clamping head (441) is movably connected to the gear adjusting member (440), the sliding member (430) is correspondingly provided with a plurality of gear grooves (431), the gear adjusting mechanism has a switchable fixed state and a sliding state, in the fixed state, the clamping head (441) slides outwards to be clamped in the gear grooves (431) so that the sliding member (430) and the gear adjusting member (440) are relatively fixed, and in the sliding state, the clamping head (441) slides inwards to retract into the gear adjusting member (440) and to avoid the gear grooves (431), so that the sliding member (430) can slide again relative to the gear adjusting member (440).

12. The seat according to claim 9, wherein the sliding member (430) is of a plate-shaped structure, a first sliding supporting groove (432) extending along a front-rear direction is hollowed out on the sliding member (430), a gear adjusting member (440) is connected to the sliding member (430) in a sliding manner, a limiting portion (442) is formed on the gear adjusting member (440) in a protruding manner, the limiting portion (442) penetrates through the first sliding supporting groove (432) and is connected to the sliding supporting portion (420), the sliding member (430) is clamped between the sliding supporting portion (420) and the gear adjusting member (440), and the sliding member (430) slides front-rear relative to the limiting portion (442) through the first sliding supporting groove (432).

13. The seat according to claim 1, wherein the lower end of the seat (2) is provided with two laterally symmetrical chassis connecting portions (210), the two chassis connecting portions (210) are attached to the left and right sides of the seat supporting portion (3), the chassis connecting portions (210) and the seat supporting portion (3) are connected by a guide mechanism, the guide mechanism comprises a guide groove (211) and a guide pin (301) which are slidably matched with each other, the guide groove (211) is provided in one of the chassis connecting portions (210) and the seat supporting portion (3), and the guide pin (301) is provided in the other of the chassis connecting portions (210) and the seat supporting portion (3).

14. The seat according to claim 13, wherein the guide groove (211) includes a lumbar support guide portion (211 a) and a tilt guide portion (211 b), both the lumbar support guide portion (211 a) and the tilt guide portion (211 b) are disposed obliquely, the direction of inclination is from front to back, from low to high, and the inclination of the lumbar support guide portion (211 a) with respect to the horizontal plane is greater than the tilt guide portion (211 b).

15. The seat according to claim 13, wherein the short strut (510) is hinged to the front end of the seat (2), the chassis connection portion (210) is provided at the rear end of the seat (2) and the guide groove (211) is provided at the chassis connection portion (210).

16. The seat according to claim 1, characterized in that a third elastic member (220) is provided between the seat (2) and the seat support (3), the third elastic member (220) not applying an elastic force to the seat (2) and the seat support (3) in an initial state, the third elastic member (220) applying a pushing force to the seat (2) and the seat support (3) in an adaptive lumbar support state so that the seat (2) has a tendency to move in a direction away from the seat support (3), and the third elastic member (220) applying a pulling force to the seat (2) and the seat support (3) in a self-tilting state so that the seat (2) has a tendency to move in a direction approaching the seat support (3).

17. The seat according to claim 16, wherein the third elastic member (220) is a controllable gas spring, the seat (2) and the third elastic member (220) are connected by a wire control mechanism, the wire control mechanism comprises an adjusting switch (230) and a pull rope connected between the adjusting switch (230) and the third elastic member (220), and the adjusting switch (230) is configured to adjust the pull rope to pull or release a thimble of the third elastic member (220), so that the third elastic member (220) can be fixed at any telescopic length.