CN114468636A

CN114468636A - Chair with detachable seat

Info

Publication number: CN114468636A
Application number: CN202210089021.XA
Authority: CN
Inventors: 江军
Original assignee: Suzhou Dafengqi Information Technology Co ltd
Current assignee: Suzhou Dafengqi Information Technology Co ltd
Priority date: 2022-01-25
Filing date: 2022-01-25
Publication date: 2022-05-13
Anticipated expiration: 2042-01-25
Also published as: CN114468636B

Abstract

The application relates to the field of chairs, in particular to a chair, which comprises a base and a backrest, wherein the backrest is arranged on the base, the chair further comprises a lifting assembly and an armpit supporting support, the armpit supporting support is arranged on the lifting assembly and can rotate relative to the lifting assembly, and the lifting assembly is connected with the backrest or the base. This application has and to make the people who sits work for a long time, and first half body weight obtains effective support, alleviates the intervertebral disc's of backbone pressure, alleviates the tired sense of back muscle, and the reinforcing travelling comfort improves work efficiency. The armpit supporting support and the chin support are particularly suitable for students to use, can support the weight of the upper body and the head, reduce the fatigue feeling of the spine and the cervical vertebra, and can be used for standardizing from childhood and maintaining the healthy upright posture of the students, thereby effectively preventing myopia, scoliosis and easy movement in class.

Description

Chair seat

Technical Field

The present application relates to the field of chairs, and more particularly, to a chair.

Background

The seat is very common in daily life, including car seat, student's seat, office chair etc. in order to alleviate the pressure of the intervertebral disc of people when sitting on the seat, can add the handrail on the seat usually, carries out auxiliary stay to the human body, alleviates person's fatigue of taking.

However, the armrest of the existing chair is generally low and relatively forward, and the user can only sit down and get up to play a role of auxiliary support. When a user goes at a desk for working or drives, the handrail hardly has the function of supporting the body.

Disclosure of Invention

In order to be able to support the upper body of a user while driving or working, the present application provides a seat.

The application provides a seat, adopts following technical scheme:

the utility model provides a seat, includes base and back, the back sets up on the base, still includes lifting unit and armpit and supports the support, the armpit supports the support and sets up on lifting unit, and can rotate with lifting unit relatively, lifting unit is connected with back or base.

By adopting the technical scheme, the lifting component drives the armpit supporting bracket to lift, so that the upper body of a user can be conveniently supported, the fatigue of the user is relieved, and the intervertebral pressure is reduced.

In a specific possible embodiment, the lifting assembly is connected with the backrest, the lifting assembly comprises a lifting rod, a lifting sleeve and a mounting seat, the lifting rod is connected with the backrest, the lifting sleeve is sleeved on the lifting rod, the mounting seat is arranged on the outer wall of the lifting sleeve, and the underarm support holder is arranged on the mounting seat;

the lifting sleeve is provided with a mounting hole, a sliding block is arranged in the mounting hole, accommodating holes are formed in the top surface and the bottom surface of the sliding block, a spring is arranged in each accommodating hole, one end of each spring is arranged on the inner wall of each accommodating hole, the other end of each spring is arranged on the inner wall of each mounting hole, a plurality of limiting grooves extending horizontally are formed in the side wall of each lifting rod and are distributed along the length direction of each lifting rod at intervals, a connecting groove is formed in one surface of each sliding block, facing the lifting rod, and a roller is arranged in each connecting groove.

Through adopting above-mentioned technical scheme, the slider that slides makes the roller roll between spacing groove and spread groove, conveniently adjusts the position of lift cover on the lifter, conveniently adapts to the user of different sizes.

In a specific implementation scheme, the lifting assembly comprises a lifting seat, a supporting column and a plurality of adjusting rods, the supporting column is connected with the base, the lifting seat is arranged at the top end of the supporting column, the adjusting rods are arranged on the bottom surface of the lifting seat, a first latch is arranged on the side wall of each adjusting rod, and a plurality of jacks for the inserting of the adjusting rods are formed in the supporting column;

the support column is internally provided with an installation cavity, a locking assembly connected with the first latch is arranged in the installation cavity, a plurality of connection holes communicated with the insertion hole are formed in the support column at intervals, and the installation cavity is communicated with the connection holes;

the locking assembly comprises a transmission gear and a plurality of transmission racks, the transmission gear is arranged on the inner wall of the installation cavity, the transmission racks are arranged in the connecting holes, the transmission gear is meshed with the transmission racks, and second clamping teeth which can be meshed with the first clamping teeth are arranged at one end, facing the adjusting rod, of the transmission racks.

Through adopting above-mentioned technical scheme, locking Assembly is connected with the latch, promotes the stability to the locking of adjusting lever. The transmission gears are rotated to simultaneously drive the first transmission racks to slide, so that the locking of the multiple adjusting rods is conveniently and simultaneously controlled, the lifting of the lifting seat is conveniently and rapidly carried out, and the height adjusting efficiency of the armpit supporting support is improved.

In a specific embodiment, the cover is equipped with the driving pipe in drive gear's the pivot, the driving pipe with the pivot splined connection of transmission shaft, the lateral wall that the driving pipe runs through the support column outwards extends, be equipped with spacing tooth on the outer wall of driving pipe, set up the draw-in groove that supplies spacing tooth joint on the lateral wall of support column.

Through adopting above-mentioned technical scheme, spacing tooth joint blocks drive gear and rotates in the draw-in groove, promotes the stability that the armpit supported the support after accomplishing altitude mixture control.

In a specific implementation scheme, a supporting shaft is arranged on the bottom surface of the armpit supporting support, an installation pipe is sleeved on the supporting shaft, a supporting plate is arranged on the side wall of the installation pipe, a stop block is arranged on the supporting shaft, a limiting block is arranged on the supporting plate, and the stop block is located on the rotation track of the limiting block.

Through adopting above-mentioned technical scheme, the layer board rotates and is the level after, and dog and stopper block that the layer board further rotates, conveniently handles official business on the layer board, perhaps supports user's chin utilizing the layer board, through the layer board to the restriction of human body, adjusts the position of sitting that uses this.

In a specific possible embodiment, the supporting plate comprises a connecting frame and a mounting plate, the connecting frame is connected with the mounting pipe, the mounting plate is hinged in the connecting frame, and a chin rest is arranged on one side of the mounting plate.

Through adopting above-mentioned technical scheme, the mounting panel is at the link internal rotation, selects the different working face of mounting panel according to the user demand. The one side that sets up the chin rest can be used for correcting user's position of sitting, and the smooth one side of mounting panel can be used for the official working.

In a specific implementation scheme, the side wall of the mounting plate is provided with a fixing hole, the side wall of the connecting frame is provided with a yielding hole communicated with the fixing hole, and the fixing hole is internally provided with a connecting pin.

Through adopting above-mentioned technical scheme, the connecting pin blocks the mounting panel at the inside rotation of linking frame, promotes the stability of mounting panel in the linking frame.

In a particular embodiment, the connection frame is hinged to the mounting tube.

Through adopting above-mentioned technical scheme, when the user need temporarily leave the seat, the layer board level is rotated and is abducted, and convenience of customers leaves the seat and reduces the influence to user's official working.

In a specific can implementation scheme, support column, armpit support hold in the palm and the back shaft is provided with two sets ofly, the layer board rotates when being the level and another back shaft overlap joint, the armpit supports and holds in the palm and offer the groove of stepping down that supplies the back shaft joint.

Through adopting above-mentioned technical scheme, two back shafts support the layer board simultaneously, reduce the pressure concentration of layer board and installation union coupling department, increase of service life. The groove of stepping down blocks the relative displacement of layer board and back shaft, promotes the stability behind layer board and the back shaft connection.

In a specific implementation scheme, a blind hole is formed in the top surface of the backrest, a connecting rod is arranged in the blind hole, a supporting rod is hinged to the top end of the connecting rod, a supporting block is arranged on the supporting rod, a pin shaft is arranged on the bottom surface of the supporting block, and a clamping hole for the pin shaft to insert is formed in the supporting rod.

Through adopting above-mentioned technical scheme, rotate the bracing piece and carry out receiving and releasing of tray, when the bracing piece rotated to the level, rotated tray to user chin below, can support user's chin, supplied user's neck to have a rest.

In summary, the present application includes at least one of the following beneficial technical effects:

1. the lifting assembly drives the lifting seat to lift up and down, and the armpit supporting bracket is driven to lift in the lifting process of the lifting seat, so that the height of the lifting plate can be conveniently adjusted according to different body types of users, and the supporting effect of the armpit supporting bracket is improved;

2. support and set up the layer board between holding in the palm at the armpit to set up chin support on the layer board, highly making user's chin and chin support contact through promoting the layer board, support user's head, and rectify user's position of sitting.

Drawings

Fig. 1 is a schematic view of the entire structure of embodiment 1.

Fig. 2 is a sectional view showing an internal structure of the backrest.

Fig. 3 is a sectional view showing the internal structure of the lifting sleeve.

Fig. 4 is a sectional view showing the internal structure of the backrest.

Fig. 5 is a schematic structural view showing that the lifting assembly is arranged on the student chair.

FIG. 6 is a schematic view of the entire structure of embodiment 2.

Fig. 7 is a schematic view showing the structure of the underarm support tray.

Fig. 8 is a sectional view showing the internal structure of the support column.

Fig. 9 is an exploded view showing the internal structure of the support column.

Fig. 10 is a schematic diagram showing a structure embodying a pallet.

Fig. 11 is a schematic view showing a connection relationship between the support shaft and the mounting pipe.

Fig. 12 is a schematic structural view of the supporting column arranged on the student chair.

Description of reference numerals: 1. a support pillar; 2. a lifting seat; 3. an underarm support bracket; 4. a locking assembly; 41. a transmission gear; 42. a drive rack; 5. a support plate; 51. a connecting frame; 52. mounting a plate; 53. a chin rest; 54. a fixing hole; 55. a hole of abdication; 56. a connecting pin; 6. adjusting a rod; 7. a first latch; 8. a second latch; 9. a jack; 10. connecting holes; 11. a mounting cavity; 12. a drive tube; 13. limiting teeth; 14. a card slot; 15. a handle; 16. a support shaft; 17. installing a pipe; 18. a yielding groove; 19. a stopper; 20. a limiting block; 21. a base; 22. a backrest; 23. a lifting assembly; 24. a lifting rod; 25. a mounting seat; 26. a lifting sleeve; 27. an accommodating chamber; 28. mounting holes; 29. a slider; 30. an accommodation hole; 31. a spring; 32. a roller; 33. a limiting groove; 34. connecting grooves; 35. a seat belt; 36. blind holes; 37. a connecting rod; 38. a support bar; 39. a support block; 40. a pin shaft; 43. and (6) clamping the hole.

Detailed Description

The present application is described in further detail below with reference to figures 1-11.

Referring to fig. 1 and 2, a car seat is first exemplified and includes a base 21, a backrest 22, two sets of lifting assemblies 23, and two underarm support brackets 3, wherein the backrest 22 is disposed on the base 21, the two sets of lifting assemblies 23 are disposed on both sides of the backrest 22, and the underarm support brackets 3 are disposed on the lifting assemblies 23 and can rotate relative to the lifting assemblies 23. The user supports 3 in the armpit that goes up and down before the driving, makes the armpit support 3 and can support user armpit position to support user's the first half body, reduce the pressure that the user drove the in-process intervertebral disc, alleviate and drive fatigue.

Referring to fig. 2 and 3, the lifting assembly 23 includes a lifting rod 24, a lifting sleeve 26 and a mounting seat 25, a containing cavity 27 is formed in the backrest 22, the lifting rod 24 is arranged in the containing cavity 27, the lifting sleeve 26 is sleeved on the lifting rod 24, the mounting seat 25 is fixed on the outer wall of the lifting sleeve 26, and the armpit support 3 is hinged on the mounting seat 25. The lifting sleeve 26 slides up and down along the lifting rod 24 to drive the mounting seat 25 to lift up and down, and further drive the armpit supporting bracket 3 to lift up and down to support the user.

Referring to fig. 2 and 3, a mounting hole 28 is formed in the lifting sleeve 26, a slider 29 is arranged in the mounting hole 28, receiving holes 30 are formed in the top surface and the bottom surface of the slider 29, a spring 31 is arranged in each receiving hole 30, one end of each spring 31 abuts against the inner wall of each receiving hole 30, and the other end of each spring 31 abuts against the inner wall of each mounting hole 28. Offer many level extending's spacing groove 33 on the lateral wall of lifter 24, many spacing grooves 33 are arranged along the length direction interval of lifter 24, and two spread grooves 34 have all been offered towards every slider 29 in the one side of lifter 24, and spread groove 34 and spacing groove 33 intercommunication all are equipped with roller 32 in every spread groove 34. Under the normal state, the roller 32 is blocked in the limit groove 33, the limit groove 33 and the connecting groove 34 are in a staggered state, and at the moment, the roller 32 blocks the sliding of the lifting sleeve 26 on the lifting rod 24, so that the user can be supported conveniently. When the armpit supporting bracket 3 needs to be adjusted to lift, the sliding block 29 is pushed upwards to enable the limiting groove 33 to be communicated with the connecting groove 34, the roller 32 can enter the connecting groove 34, at the moment, the lifting sleeve 26 is moved to freely adjust the position of the armpit supporting bracket 3, and after the adjustment is completed, the sliding block 29 is slid downwards to lock the position of the armpit supporting bracket 3.

Referring to fig. 4, a blind hole 36 is formed in the top surface of the backrest 22, a connecting rod 37 is inserted into the blind hole 36, a supporting rod 38 is hinged to the top end of the connecting rod 37, and the supporting rod 38 cannot further rotate downwards after rotating to the horizontal state. A support block 39 is arranged at one end of the support rod 38 far away from the connecting rod 37, two pin shafts 40 are fixed on the bottom surface of the support block 39, and a clamping hole 43 for the pin shaft 40 to be inserted is formed in the support rod 38. The supporting block 39 is connected with the connecting rod 37 through a pin shaft 40 and a clamping hole 43 and can rotate around the axis of the pin shaft 40. In a normal state, the support rod 38 and the connecting rod 37 are approximately in a straight line and are accommodated in the blind hole 36, when the support rod 38 is pulled out and rotated to be horizontal, the support block 39 is rotated, the two pin shafts 40 are inserted into the clamping holes 43, and the support rod 38 supports the support block 39. The user can rest the chin on the support block 39, and utilize the support block 39 to support the chin, alleviate the pressure that the neck received, alleviate fatigue.

In some other embodiments, a torsion spring may be disposed at the hinge joint of the connecting rod 37 and the supporting rod 38, and in the blind hole 36, so that after the connection with the supporting block 39 is released, the supporting rod 38 can automatically return, and is convenient and fast to store.

Referring to fig. 1, a safety belt 35 is fixed to the underarm support 3, and a user can be fixed to the seat through the safety belt 35, thereby improving the safety of the user.

Referring to fig. 5, when the elevation assembly 23 is provided on the student seat, the elevation bar 24 may be replaced with a fixing bar of the student seat back 22.

Example 2:

referring to fig. 5, 6 and 7, embodiment 2 differs from embodiment 1 in that the lifting assembly 23 includes a lifting base 2, a supporting column 1 and a plurality of adjusting rods 6, the supporting column 1 is fixed on the side wall of the base 21, the lifting base 2 is arranged at the top end of the supporting column 1, and the underarm supporting tray 3 is hinged at one end of the lifting base 2. Support column 1, lift seat 2 and armpit support 3 divide two sets of symmetries to set up in the both sides of seat, during the use, turn over the armpit and support 3 and be the level, and the person of facilitating the use places positions such as elbow on the armpit supports 3, alleviates user's position of sitting fatigue. After the use is finished, the armpit supporting supports 3 are turned over to be in a vertical state, so that a user can conveniently leave the chair.

Referring to fig. 8, a plurality of adjusting rods 6 are vertically fixed on the bottom surface of the lifting seat 2, and a first latch 7 is integrally formed on the side wall of each adjusting rod 6. Set up a plurality of jacks 9 that supply adjusting rod 6 to insert to establish on the support column 1, seted up installation cavity 11 in the support column 1, be equipped with the locking Assembly 4 of being connected with first latch 7 in the installation cavity 11. Lifting seat 2 is connected with support column 1 through adjusting pole 6 to under the direction of adjusting pole 6, go up and down along vertical direction, the convenience is according to the user of different sizes, adjusts the armpit and supports the height that holds in the palm 3, adapts to different support demands, promotes the supporting effect. Simultaneously according to the length of the latch that exposes, can adjust the height of lift seat 2 more accurately, and then promote the armpit and support the regulation precision that holds in the palm 3, further promote the support effect.

Referring to fig. 8, two connection holes 10 communicated with the insertion hole 9 are formed in the support column 1, two ends of each connection hole 10 are communicated with the insertion hole 9, and the installation cavity 11 is communicated with each connection hole 10. The locking assembly 4 comprises a transmission gear 41 and two transmission racks 42, the transmission gear 41 is arranged in the installation cavity 11, the transmission racks 42 are arranged in the connecting holes 10, the transmission racks 42 can slide in the connecting holes 10, the two transmission racks 42 are all meshed with the transmission gear 41, and a second latch 8 is integrally formed on the end face, facing one end of the insertion hole 9, of each transmission rack 42. Under a normal state, the first latch 7 and the second latch 8 are in a meshed state, the transmission gear 41 is rotated to drive the transmission rack 42 to slide in a direction away from the adjusting rod 6, the second latch 8 is disengaged from the first latch 7, and the adjusting rod 6 can freely lift. After the position of the lifting seat 2 is adjusted, the transmission gear 41 is rotated reversely, the transmission rack 42 approaches the adjusting rod 6, and the second latch 8 is engaged with the first latch 7 again. The locking and the movement of a plurality of adjusting rods 6 can be controlled simultaneously through the rotation of the transmission gear 41, the position of the armpit supporting bracket 3 can be adjusted conveniently and rapidly, and the adjusting efficiency of the position of the armpit supporting bracket 3 is improved.

Referring to fig. 8 and 9, a transmission tube 12 is coaxially sleeved on a rotating shaft of the transmission gear 41, the rotating shaft of the transmission tube 12 and the rotating shaft of the transmission gear 41 are connected through a spline, the transmission tube 12 penetrates through the side wall of the support column 1 and extends, a handle 15 is fixed at one end of the transmission tube 12 outside the support column 1, a limit tooth 13 is fixed on the outer wall of the transmission tube 12, and a clamping groove 14 for clamping the limit tooth 13 is formed in the side wall of the support column 1. When the height of the lifting seat 2 needs to be adjusted, the handle 15 is pulled outwards, the limiting teeth 13 are separated from the clamping groove 14, and the driving rack 42 can be driven to slide by rotating the handle 15. After the adjustment is completed, the handle 15 is rotated reversely, after the first latch 7 is meshed with the second latch 8, the handle 15 is pressed, the limiting teeth 13 are clamped into the clamping grooves 14, the transmission gear 41 is blocked from rotating, and the locking stability of the adjusting rod 6 is improved.

Referring to fig. 10 and 11, a supporting shaft 16 is detachably connected to the bottom surface of the armpit supporting bracket 3, a mounting pipe 17 is sleeved on the supporting shaft 16, the mounting pipe 17 can rotate relative to the supporting shaft 16, a supporting plate 5 is hinged to the side wall of the mounting pipe 17, and the hinge shaft of the supporting plate 5 and the mounting pipe 17 is perpendicular to the axis of the supporting shaft 16. A stop block 19 is fixed on the side wall of the supporting shaft 16, a limit block 20 is integrally formed on the end face of one end of the mounting pipe 17 facing the armpit supporting bracket 3, and the stop block 19 is positioned on the rotating track of the limit block 20. The installation pipe 17 rotates on the back shaft 16 and drives the layer board 5 to rotate, makes layer board 5 switch in vertical state and horizontality, and when layer board 5 rotated and is approximate level, dog 19 and stopper 20 offset, blockked layer board 5 and further rotated, and the person of facilitating the use official working on layer board 5. At this time, the supporting plate 5 and the hinge shaft of the installation pipe 17 are in an approximately vertical state, and when a user needs to leave the seat, the user can conveniently leave by rotating the supporting plate 5. After the use of the supporting plate 5 is completed, the supporting plate 5 is rotated around the supporting shaft 16, so that the supporting plate 5 is in a vertical state, and the supporting plate 5 is convenient to store.

Referring to fig. 10, the pallet 5 includes a connection frame 51 and a mounting plate 52, the mounting plate 52 is disposed within the connection frame 51 and can rotate independently of the connection frame 51, and the connection frame 51 is hinged to the mounting pipe 17. A chin rest 53 is fixed to the top surface of the mounting plate 52. The mounting plate 52 is lifted to the chin of the user, and the user can rest the chin on the chin rest 53, which is convenient for correcting the sitting posture of the user. Meanwhile, when the sitting posture correction is not needed, the mounting plate 52 is turned over, and the office can be performed on the other flat surface of the mounting plate 52.

Referring to fig. 10, the length of the connection frame 51 is greater than the interval between the two support shafts 16, the yielding groove 18 is formed in the bottom surface of the end, away from the installation pipe 17, of the connection frame 51, when the connection frame 51 rotates to be horizontal, the yielding groove 18 is connected with the support shafts 16 in a clamping mode, the connection frame 51 is supported through the two support shafts 16, the pressure on the hinged position of the connection frame 51 and the installation pipe 17 is reduced, and the stability of connection of the connection frame 51 and the support shafts 16 is improved.

Referring to fig. 10, a plurality of fixing holes 54 are formed in the side wall of the mounting plate 52, a relief hole 55 communicating with the fixing holes 54 is formed through the side wall of the connection frame 51, and a connection pin 56 is inserted into the fixing hole 54. After the mounting plate 52 is turned over as required, the connecting pin 56 is inserted into the hole 55 and the fixing hole 54, the connecting pin 56 stops the mounting plate 52 from rotating in the connecting frame 51, and the stability of the mounting plate 52 in the connecting frame 51 is improved.

Referring to fig. 6, the structure of the seat is freely adjusted according to an actual use scene, and when the seat is installed in a scene such as an automobile seat where the support plate 5 is not necessary, parts such as the support shaft 16 on the bottom surface of the armpit support 3 are removed, and the support column 1, the lifting seat 2, the armpit support 3, and the like are left. The adjusting rod 6 is loosened by rotating the handle 15, and then the lifting seat 2 is adjusted to lift and adjust according to the body type of a user. The automatic lifting structure through setting up electric cylinder etc. in the installation cavity 11 of erection column drives lift seat 2 and goes up and down, is assisted again with the control structure of gravity sensor, height finding sensor etc. carries out the regulation that automatic armpit supported support 3 according to people's size.

Referring to fig. 12, when the seat is set in an office scene, the tray 5 can be rotated as necessary to work on the tray 5. For example, when the student uses the device, the student has an irregular sitting posture, the height of the supporting plate 5 is increased, the chin of the student is placed on the chin rest 53, the healthy body of the student is standardized through the blocking effect of the supporting plate 5 and the chin rest 53, the sitting posture is corrected, the fatigue of the spine and the cervical vertebra of the student in class is relieved, myopia is prevented, scoliosis is prevented and corrected, and the healthy upright posture is taken out from small specifications. After the use is finished, the supporting plate 5 is rotated to finish the storage rapidly.

In some other embodiments, a locking device may be further disposed between the underarm support 3 and the connecting frame 51 to lock the connection between the underarm support 3 and the connecting frame 51, so as to improve the stability of the connection between the underarm support 3 and the connecting frame 51.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. A seat comprising a base (21) and a backrest (22), the backrest (22) being disposed on the base (21), characterized in that: still include lifting unit (23) and armpit and support and hold in the palm (3), armpit supports and holds in the palm (3) setting on lifting unit (23), and can rotate with lifting unit (23) relatively, lifting unit (23) are connected with back (22) or base (21).

2. A seat as claimed in claim 1, wherein: the lifting assembly (23) is connected with the backrest (22), the lifting assembly (23) comprises a lifting rod (24), a lifting sleeve (26) and a mounting seat (25), the lifting rod (24) is connected with the backrest (22), the lifting sleeve (26) is sleeved on the lifting rod (24), the mounting seat (25) is arranged on the outer wall of the lifting sleeve (26), and the armpit supporting support (3) is arranged on the mounting seat (25);

mounting hole (28) have been seted up on lift cover (26), be equipped with slider (29) in mounting hole (28), accommodation hole (30) have all been seted up on the top surface of slider (29) and on the bottom surface, every all be equipped with spring (31) in accommodation hole (30), spring (31) one end sets up on accommodation hole (30) inner wall, and the other end sets up on the inner wall of mounting hole (28), be equipped with spacing groove (33) that many levels extend on the lateral wall of lifter (24), many spacing groove (33) are arranged along lifter (24) length direction interval, connecting groove (34) have been seted up in the one side of slider (29) towards lifter (24), be equipped with roller (32) in connecting groove (34).

3. A seat as claimed in claim 1, wherein: the lifting assembly (23) comprises a lifting seat (2), a supporting column (1) and a plurality of adjusting rods (6), the supporting column (1) is connected with a base (21), the lifting seat (2) is arranged at the top end of the supporting column (1), the adjusting rods (6) are all arranged on the bottom surface of the lifting seat (2), a first clamping tooth (7) is arranged on the side wall of each adjusting rod (6), and the supporting column (1) is provided with a plurality of jacks (9) for the inserting of the adjusting rods (6);

a mounting cavity (11) is formed in the supporting column (1), a locking assembly connected with the first clamping tooth (7) is arranged in the mounting cavity (11), a plurality of connecting holes (10) communicated with the jack (9) are formed in the supporting column (1) at intervals, and the mounting cavity (11) is communicated with the connecting holes (10);

locking Assembly (4) include drive gear (41) and many driving rack (42), drive gear (41) set up on the inner wall of installation cavity (11), driving rack (42) set up in connecting hole (10), drive gear (41) and driving rack (42) mesh mutually, driving rack (42) are equipped with second latch (8) that can mesh mutually with first latch (7) towards the one end of adjusting pole (6).

4. A seat according to claim 3, wherein: the cover is equipped with driving pipe (12) in the pivot of drive gear (41), driving pipe (12) with the pivot splined connection of drive gear (41), the lateral wall that driving pipe (12) run through support column (1) outwards extends, be equipped with spacing tooth (13) on the outer wall of driving pipe (12), offer draw-in groove (14) that supply spacing tooth (13) joint on the lateral wall of support column (1).

5. A seat as claimed in claim 1, wherein: be equipped with back shaft (16) on the bottom surface that the armpit supported support (3), the cover is equipped with installation pipe (17) on back shaft (16), be equipped with layer board (5) on the lateral wall of installation pipe (17), be equipped with dog (19) on back shaft (16), be equipped with stopper (20) on layer board (5), dog (19) are in on the rotation orbit of stopper (20).

6. A seat according to claim 5, wherein: layer board (5) are including linking frame (51) and mounting panel (52), linking frame (51) are connected with installation pipe (17), mounting panel (52) articulate in linking frame (51), mounting panel (52) are equipped with chin strap (53) in the one side.

7. A seat according to claim 6, wherein: the fixing hole (54) has been seted up on the lateral wall of mounting panel (52), set up hole of stepping down (55) with fixing hole (54) intercommunication on the lateral wall of connecting frame (51), be equipped with connecting pin (56) in fixing hole (54).

8. A seat according to claim 7, wherein: the connecting frame (51) is hinged with the mounting tube (17).

9. A seat according to claim 5, wherein: support column (1), armpit support hold in the palm (3) and back shaft (16) and be provided with two sets ofly, layer board (5) rotate when being the level with another back shaft (16) overlap joint, armpit support holds in the palm and offers offering the groove of stepping down (18) that supplies back shaft (16) joint on (3).

10. A seat as claimed in claim 1, wherein: the utility model discloses a chair backrest, including backrest (22), blind hole (36) have been seted up on the top surface of backrest (22), be equipped with connecting rod (37) in blind hole (36), the top of connecting rod (37) articulates there is bracing piece (38), be equipped with tray (39) on bracing piece (38), be equipped with round pin axle (40) on the bottom surface of tray (39), set up on bracing piece (38) and supply round pin axle (40) male card hole (43).