CN210027117U

CN210027117U - Child safety seat

Info

Publication number: CN210027117U
Application number: CN201920477899.4U
Authority: CN
Inventors: 钱建洪; 裘杭建; 陈凯新
Original assignee: Hangzhou Yue Meng Industrial Co Ltd
Current assignee: Butong safety technology (Ningbo) Co.,Ltd.
Priority date: 2019-04-10
Filing date: 2019-04-10
Publication date: 2020-02-07
Anticipated expiration: 2029-04-10

Abstract

The utility model relates to a children's safety seat field discloses children's safety seat, and it includes the screw rod of left first linking arm, the second linking arm on right side and be used for connecting first linking arm and second linking arm, is provided with the rolling member on the screw rod, drives the screw rod synchronous rotation when the rolling member rolls, and the screw rod rotates and drives first linking arm and second linking arm and carry out relative or opposite movement. The child safety seat has the characteristics of reliable connection and stable and fixed transmission, and the screw rod is in threaded fit with the connecting arm, so that the child safety seat has the advantages of compact structure, high connection strength, difficult shaking phenomenon, good safety, long service life and low space occupancy rate; the rolling member is the gear, and direction transmission portion is the rack, and rack and pinion simple structure is with low costs, and rack and pinion meshing, the bearing capacity is big, and the transmission is stable, and transmission precision is high, and wearing and tearing are little, and the noise is little, and it is high to adjust the precision, and the space occupies for a short time, and is with low costs, and installation and maintenance are convenient to be adjusted conveniently, long service life.

Description

Child safety seat

Technical Field

The utility model relates to a seat field has especially related to children's safety seat.

Background

As children grow, the height of the headrest and the shoulder straps of the safety seat needs to be adjusted to accommodate different body heights and body sizes. The most way of dealing with children of different ages that current children's safety seat adopted is, adopt the integral type seat, set up the cushion in the seat, adopt the mode that the seat adds the cushion to the less infant of size, to the great children of size, then remove the cushion, take in the integral type seat, do not have flank automatically regulated mechanism, the installation need be disassembled to the flank height, also some can be along with the mechanism of headrest altitude mixture control automatically regulated flank height, but can not adjust the width space between the inside flank of seat, moreover, the structure is complicated, the operation is inconvenient. The position adjustment of the headrest and the side wings of the child safety seat not only affects the comfort of the child, but also affects the life safety of the child. Therefore, the child safety seat needs to be provided with an adjusting mechanism capable of synchronously adjusting the width of the side wings and the height of the headrest so as to adapt to children of different ages and sizes.

Chinese patent No. CN207631041U discloses a synchronous adjustment structure for child safety seats, which is characterized in that two transverse sliding grooves are symmetrically arranged on the left and right sides of the backrest body, two transverse connecting arms are slidably mounted in the two transverse sliding grooves, and two sets of vertically extending guide grooves are symmetrically arranged on the backrest body, and are inclined from top to bottom along the backrest body and gradually close to the backrest body, and sliding blocks which are in guide sliding fit with the corresponding guide grooves are respectively fixed on the connecting arms to adjust the width of the seat clamping arms. But it is with high costs to have seting up of two sets of guide ways on leaning against the body of this adjustment mechanism's safety seat, it is not good to lean against board stability, the structure is complicated, it is inconvenient to install and maintain, the regulative mode is comparatively complicated, whole mechanism structural stability is not strong, easily produce and rock, the slip smoothness nature of slider is not good, the slider is along the equal atress of the lateral wall of controlling of guide way when the guide way slides, the jamming phenomenon appears easily, and control the lateral wall and easily wear and tear, when a lateral wall goes wrong, just unable normal work of whole mechanism, the fault rate of product has been increased.

Chinese patent No. CN207697551U discloses a headrest height adjusting and flank width adjusting mechanism of a child safety seat, which comprises a seat, the upper portion of the seat is provided with a headrest, the two side ends of the seat are respectively provided with a flank, the seat and the headrest are adjusted up and down through a headrest height adjusting component, the flank and the seat are adjusted up and down through a width adjusting component. The adjusting mechanism has the advantages of convenient disassembly and compact structure. But in the in-service use process, the product processing technology is more complicated for seting up of its spout, and it is comparatively inconvenient to maintain, has still occupied the more space of back plate, and the joint strength of spout and guide is little, and the regulation precision is little, and the stability of flank is relatively poor simultaneously, can appear rocking phenomenon after long-term the use, and the security is not strong.

SUMMERY OF THE UTILITY MODEL

The utility model discloses child safety seat structure is complicated among the prior art, and whole mechanism stability is not strong, and easy production is rocked, and it is little to adjust the precision, and the space occupies greatly, and is with high costs, and seat installation and maintenance shortcoming such as inconvenient provide a simple structure compactness, adjust conveniently, and whole mechanism joint strength is high, and the security is good, adjusts the precision height, and the space occupies for a short time, and is with low costs, installation and maintenance convenient child safety seat.

In order to solve the technical problem, the utility model discloses a following technical scheme can solve: child safety seat, including left first linking arm, the second linking arm on right side and the back board of being connected with the seat base, still including the screw rod that is used for connecting first linking arm and second linking arm, be provided with the rolling member on the screw rod, be provided with on the back board with rolling member complex direction transmission portion, the rolling member drives the screw rod synchronous rotation when upwards rolling or rolling downwards along direction transmission portion, the screw rod rotates and drives first linking arm and second linking arm and carry out relative or opposite movement. The screw transmission has the characteristics of reliable connection and stable and fixed transmission, and the screw and connecting arm are matched, so that the screw transmission has the advantages of compact structure, high connection strength, good safety and low space occupancy rate, the screw and connecting arm are good in adjustment synchronism, the first connecting arm and the second connecting arm are controllable in adjustment and high in precision, the connecting arm can be adjusted at a stable position, and the shaking phenomenon is not easy to occur; the rolling piece is matched with the guide transmission part in a rolling way, and has the characteristics of stable transmission and small friction force; the screw rod is driven to rotate by the upward or downward movement of the rolling piece along the guide transmission part, and the first connecting arm and the second connecting arm are driven to move oppositely or oppositely by the rotation of the screw rod, so that the first connecting arm and the second connecting arm are close to or far away from each other, and the width adjustment between the left side wing and the right side wing is realized.

Preferably, the guide transmission part is a rack, the rack is arranged on the backrest plate along the vertical direction, the rolling part is a gear, and the gear is meshed with the rack. The gear rack has the advantages of being simple in structure, low in cost, meshed with the gear rack, large in bearing capacity, stable in transmission, high in transmission precision, small in abrasion and low in noise, stable in transmission, high in safety and reliability and better in use experience.

Preferably, the rack is integrally formed with the back plate or detachably connected thereto. The rack can be directly arranged on the back plate and also can be independently arranged on the back plate, and the integrated forming design and processing technology is simple, low in cost, good in detachable connection controllability and convenient for replacing the rack.

Preferably, the rolling member is arranged coaxially with the screw. The screw rod is driven to rotate synchronously when the rolling piece rolls, and the synchronous movement of the rolling piece and the screw rod is ensured.

Preferably, the rolling member is integrally formed with the screw. The rolling piece and the screw rod are good in synchronism, simple in processing technology and convenient to install and maintain.

Preferably, the first connecting arm and the second connecting arm are both provided with threaded sleeves matched with the screw threads, and the threaded sleeves are detachably connected with the first connecting arm and the second connecting arm or integrally formed. The screw sleeve is in threaded fit with the screw rod, and the fastening performance is good.

Preferably, the screw comprises a first screw section in threaded connection with the first connecting arm and a second screw section in threaded connection with the second connecting arm, the threads on the first screw section and the second screw section having opposite directions of rotation. The rotation direction has the advantages that when the headrest is adjusted upwards, the gear rolls upwards to drive the screw rod to rotate, and the first connecting arm and the second connecting arm move oppositely to increase the distance between the first connecting arm and the second connecting arm, so that the characteristic of synchronously adjusting the width is realized, and the function of increasing the width of the seat while increasing the height is realized; the screw rod is in threaded connection with the connecting arm, so that the connecting strength is high, the fixing is firm, the artificial damage can be prevented, and the service life is long.

Preferably, the rolling elements are arranged in the middle of the screw, and the first screw section and the second screw section are respectively positioned on two sides of the rolling elements. The rolling part sets up in the middle part of screw rod, and simple structure is exquisite, and first linking arm and second linking arm can be close to the rolling part or keep away from the rolling part when taking place relative or when moving in opposite directions.

Preferably, the screw rod is arranged along the horizontal direction, the screw thread turning direction of the connecting part of the screw rod and the first connecting arm is right-handed, and the screw thread turning direction of the connecting part of the screw rod and the second connecting arm is left-handed. The installation is convenient, the transmission effect is good, and the adjustment is convenient; when adopting this kind to revolve to can realizing upwards promoting the headrest, the distance between first linking arm and the second linking arm increases, realizes the synchronization regulation.

Preferably, the seat further comprises a seat base, a left side wing, a right side wing, a headrest, a sliding plate fixedly connected with the headrest and a driving device used for driving the headrest to move up and down, the left side wing is fixedly connected with a first connecting arm, the right side wing is fixedly connected with a second connecting arm, sliding components are arranged between the first connecting arm and the sliding plate, each sliding component comprises a transverse sliding groove and a transverse sliding block, each transverse sliding block is embedded into the transverse sliding groove and can move left and right relative to the transverse sliding groove, one of the transverse sliding grooves and the transverse sliding blocks is arranged on the first connecting arm and the second connecting arm, the other sliding component is arranged on the sliding plate, one end of the driving device is connected with the headrest, and the other end of the driving device is connected with the seat base. The driving device drives the headrest to move up and down to adjust the height of the headrest, the headrest drives the sliding plate to move up and down, when the headrest drives the sliding plate to move up or down, the sliding plate drives the first connecting arm and the second connecting arm to move up or down synchronously through the sliding assembly, and meanwhile, the first connecting arm and the second connecting arm realize the left and right movement of the relative sliding plate through the relative left and right movement of the transverse sliding block and the transverse sliding groove; when the sliding plate drives the first connecting arm and the second connecting arm to move up and down, the first connecting arm and the second connecting arm drive the screw rod to move up and down, the rolling piece rolls up and down along the guide transmission part while the screw rod moves up and down, the rolling piece rolls to drive the screw rod to synchronously rotate, the screw rod rotates to drive the first connecting arm and the second connecting arm to move relatively or oppositely, the first connecting arm and the second connecting arm move left and right on the sliding plate through the sliding assembly, and the first connecting arm and the second connecting arm respectively drive the left flank and the right flank to be close to or far away from each other, so that the height and the width of the left flank and the right flank are synchronously adjusted.

The utility model discloses owing to adopted above technical scheme, have apparent technological effect: the child safety seat provided by the application adjusts the width of the side wing in a screw thread matching mode of the screw and the connecting arm, the screw is simple in structure, the screw transmission has the characteristics of reliable connection and stable and fixed transmission, the screw and the connecting arm are in screw thread matching and have the advantages of compact structure, high connection strength, difficulty in shaking, good safety, long service life and low space occupancy rate, the screw and the connecting arm are good in adjustment synchronism, and the connecting arm can be adjusted at a stable position by the screw, so that the adjustment of the connecting arm is controllable and the adjustment precision is high; the first screw section and the second screw section are arranged in opposite screw thread rotating directions, so that the first connecting arm and the second connecting arm can move relatively or oppositely, and the design is delicate and reliable; the screw rod is provided with a rolling part, the back plate is provided with a guide transmission part matched with the rolling part, the rolling part moves upwards or downwards along the guide transmission part to drive the screw rod to synchronously rotate, the screw rod rotates to drive the first connecting arm and the second connecting arm to relatively or oppositely move, the rolling part is a gear, the guide transmission part is a rack, and the gear and the rack are simple in structure and low in cost and meshed with each other; the rolling piece and the screw rod are integrally formed, so that the synchronism and the transmission efficiency of the rolling piece and the screw rod are ensured, the processing technology is simple, and the installation and the maintenance are convenient; the rack can be directly arranged on the back plate or independently arranged on the back plate, and the integrated forming design has the advantages of simple processing technology, low cost, good detachable connection controllability and convenience for replacing the rack; the application provides a seat is because of possessing above-mentioned children's safety seat, has and adjusts the convenience, adjusts the precision height, and the security is good, is difficult for appearing rocking, long service life, uses to experience advantages such as good.

Drawings

Fig. 1 is a schematic view of a child safety seat.

Fig. 2 is a schematic structural view of the screw.

Fig. 3 is a schematic view of a backrest plate.

Fig. 4 is a schematic view of the connection of the driving device to the headrest.

The names of the parts indicated by the numerical references in the drawings are as follows: 1-first connecting arm, 11-left flank, 2-second connecting arm, 21-right flank, 3-back plate, 31-guide transmission part, 4-screw, 41-first screw section, 42-second screw section, 43-swivel nut, 5-rolling piece, 6-headrest, 61-sliding plate, 62-driving device, 7-transverse sliding groove, 8-transverse sliding block and 9-seat base.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples.

The application is an improvement on the prior patent of the company, namely, the utility model patent CN201721579368.3 which is patented as Hangzhou Lele industry Co Ltd, namely, the improvement on a headrest height adjusting and side wing width adjusting mechanism of a child safety seat.

Example 1

The child safety seat, as shown in the figure, comprises a first connecting arm 1 on the left side, a second connecting arm 2 on the right side and a backrest 3 connected to a seat base 9, which in this embodiment is upper and lower, the left and right directions are all referred by taking the figure 1 as a reference, the first connecting arm 1 is used for connecting the left flank 11, the second connecting arm 2 is used for connecting the right flank 21, the screw rod 4 used for connecting the first connecting arm 1 and the second connecting arm 2 is further included, the screw rod 4 is provided with a rolling part 5, the back plate 3 is provided with a guide transmission part 31 matched with the rolling part 5, the rolling part 5 drives the screw rod 4 to synchronously rotate when rolling upwards or downwards along the guide transmission part 31, the screw rod 4 rotates to drive the first connecting arm 1 and the second connecting arm 2 to relatively or oppositely move, and the relative movement or the opposite movement of the first connecting arm 1 and the second connecting arm 2 depends on the forward rotation or the reverse rotation of the screw rod 4. The screw rod 4 has the characteristics of reliable connection and stable and fixed transmission, the screw rod 4 is matched with the connecting arm, and the device has the advantages of compact structure, high connection strength, high safety and low space occupancy rate, the screw rod 4 and the connecting arm are good in adjustment synchronism, the first connecting arm and the second connecting arm are controllable in adjustment and high in precision, the connecting arm can be adjusted at a stable position, and the shaking phenomenon is not easy to occur; the rolling piece 5 is matched with the guide transmission part 31 in a rolling way, and has the characteristics of stable transmission and small friction force; the screw rod 4 is driven to rotate by the upward or downward movement of the rolling piece 5 along the guide transmission part 31, and the screw rod 4 rotates to drive the first connecting arm 1 and the second connecting arm 2 to move relatively or oppositely, so that the first connecting arm 1 and the second connecting arm 2 are close to or far away from each other, and the width adjustment between the left side wing 11 and the right side wing 21 is realized.

In order to more clearly express the transmission relationship between the rolling members 5 and the guide transmission part 31 in this embodiment, the guide transmission part 31 is a rack in this embodiment, the rack is vertically disposed on the backrest plate 3, the rack is disposed inside the backrest plate 3, and the rolling members 5 are gears, and the gears are engaged with the rack. When the gear-driven type gear-driven mechanism works, the rack does not move, and the gear rolls upwards or downwards on the rack. The gear rack has the advantages of being simple in structure, low in cost, meshed with the gear rack, large in bearing capacity, stable in transmission, high in transmission precision, small in abrasion and low in noise, stable in transmission, high in safety and reliability and better in use experience.

The screw 4 comprises a first screw section 41 in threaded connection with the first connecting arm 1 and a second screw section 42 in threaded connection with the second connecting arm 2, the screw thread directions of the first screw section 41 and the second screw section 42 are opposite, the screw thread direction of the first screw section 41 is right-handed, and the screw thread direction of the second screw section 42 is left-handed. Adopt this kind to revolve to advantage lies in, when upwards adjusting headrest 6, the gear upwards rolls and drives screw rod 4 and rotate, and first linking arm 1 and second linking arm 2 take place the relative motion this moment and make the distance increase between the two, realize the characteristics of synchronous control width, when realizing that the seat height increases, the function that the width also increased simultaneously. The screw rod 4 is in threaded connection with the connecting arm, so that the connecting strength is high, the fixing is firm, the artificial damage can be prevented, and the service life is long; the opposite screw thread directions of the first screw section 41 and the second screw section 42 ensure that the first connecting arm 1 and the second connecting arm 2 can move relatively or oppositely, so as to approach or move away from each other, and the width between the left side wing 11 and the right side wing 21 can be adjusted.

The rolling element 5 is arranged in the middle of the screw 4, the first screw section 41 and the second screw section 42 are respectively located on both sides of the rolling element 5, the first screw section 41 is located on the left side of the rolling element 5, and the second screw section 42 is located on the right side of the rolling element 5. The rolling part 5 is arranged in the middle of the screw rod 4, the structure is simple and delicate, and when the connecting arms of the first connecting arm 1 and the second connecting arm 2 move oppositely or oppositely, the rolling part 5 can be close to or far away from the rolling part 5.

The rolling member 5 is arranged coaxially with the screw 4. The screw rod 4 is driven to synchronously rotate when the rolling piece 5 rolls, and the synchronous movement of the rolling piece 5 and the screw rod 4 is ensured.

All be provided with on first linking arm 1 and the second linking arm 2 and be used for with screw rod 4 screw thread fit's swivel nut 43, swivel nut 43 and first linking arm 1 and second linking arm 2 be integrated into one piece.

The screw rod 4 is arranged along the horizontal direction, the screw thread turning direction of the connecting part of the screw rod 4 and the first connecting arm 1 is right-handed, and the screw thread turning direction of the connecting part of the screw rod 4 and the second connecting arm 2 is left-handed. The installation is convenient, the transmission effect is good, and the adjustment is convenient; when the headrest 6 can be lifted upwards by adopting the rotating direction, the distance between the first connecting arm 1 and the second connecting arm 2 is increased, and synchronous adjustment is realized.

The seat comprises a seat base 9, a left side wing 11, a right side wing 21, a headrest 6, a sliding plate 61 fixedly connected with the headrest 6 and a driving device 62 for driving the headrest 6 to move up and down, wherein the left side wing 11 is fixedly connected with a first connecting arm 1, the right side wing 21 is fixedly connected with a second connecting arm 2, sliding components are respectively arranged between the first connecting arm 1 and the sliding plate 61, the sliding components comprise a transverse sliding groove 7 and a transverse sliding block 8, the transverse sliding block 8 is embedded into the transverse sliding groove 7 and can move left and right relative to the transverse sliding groove 7, one of the transverse sliding groove 7 and the transverse sliding block 8 is arranged on the first connecting arm 1 and the second connecting arm 2, the other is arranged on the sliding plate 61, the transverse sliding grooves 7 are respectively arranged on the first connecting arm 1 and the second connecting arm 2, the transverse sliding block 8 is arranged on the sliding plate 61, one end of the driving device 62 is connected with the headrest 6, the other end of the drive device 62 is connected to the seat base 9. The height of the headrest 6 is adjusted by the driving device 62, the driving device 62 can be an air supporting rod, when the headrest 6 drives the sliding plate 61 to move upwards or downwards, the sliding plate 61 drives the first connecting arm 1 and the second connecting arm 2 to move upwards or downwards synchronously through the transverse sliding block 8, and meanwhile, the first connecting arm 1 and the second connecting arm 2 move left and right relatively through the transverse sliding block 8 and the transverse sliding groove 7 to realize the left and right movement of the relative sliding plate 61.

The adjusting principle of the child safety seat is as follows: when the headrest 6 ascends, the driving device 62 drives the headrest 6 to move upwards, the height of the headrest 6 is adjusted when the headrest 6 moves upwards and downwards, when the headrest 6 ascends, the headrest 6 drives the sliding plate 61 to move upwards, the sliding plate 61 drives the first connecting arm 1 and the second connecting arm 2 to move upwards, at the moment, the first connecting arm 1 and the second connecting arm 2 respectively drive the left flank 11 and the right flank 21 to ascend, the first connecting arm 1 and the second connecting arm 2 drive the screw rod 4 to move upwards, the rolling piece 5 rolls upwards along the guide transmission part 31 while the screw rod 4 moves upwards, the rolling piece 5 rolls to drive the screw rod 4 to synchronously rotate, at the moment, the rotation direction of the screw rod 4 is positive rotation, the positive rotation of the screw rod 4 drives the first connecting arm 1 and the second connecting arm 2 to move oppositely, and simultaneously, the first connecting arm 1 is matched with the transverse sliding block 8 and the transverse sliding groove 7 to move leftwards on the sliding plate 61, the second connecting arm 2 is matched with the sliding plate 61 through the transverse sliding block 8 and the transverse sliding groove 7 to move rightwards, the first connecting arm 1 and the second connecting arm 2 are far away from each other, and at the moment, the first connecting arm 1 and the second connecting arm 2 respectively drive the left side wing 11 and the right side wing 21 to be far away from each other, so that the width between the left side wing 11 and the right side wing 21 is increased; when the headrest 6 descends, when the driving device 62 drives the headrest 6 to move downwards, the headrest 6 drives the sliding plate 61 to move downwards, the sliding plate 61 drives the first connecting arm 1 and the second connecting arm 2 to move downwards, at this time, the first connecting arm 1 and the second connecting arm 2 drive the left flank 11 and the right flank 21 to descend respectively, the first connecting arm 1 and the second connecting arm 2 drive the screw rod 4 to move downwards, the screw rod 4 moves upwards while the rolling member 5 rolls downwards along the guide transmission part 31, the rolling member 5 rolls to drive the screw rod 4 to rotate synchronously, at this time, the rotation direction of the screw rod 4 is reverse rotation, the screw rod 4 rotates reversely to drive the first connecting arm 1 and the second connecting arm 2 to move relatively, meanwhile, the first connecting arm 1 is matched with the sliding plate 61 through the transverse sliding block 8 and the transverse sliding groove 7 to move rightwards, the second connecting arm 2 is matched with the sliding plate 61 through the transverse sliding block 8 and the transverse sliding groove 7 to move leftwards, the first connecting arm 1 and the second connecting arm 2 are close to each other, and at this time, the first connecting arm 1 and the second connecting arm 2 respectively drive the left wing 11 and the right wing 21 to be close to each other, so that the width between the left wing 11 and the right wing 21 is reduced.

Example 2

The child safety seat, as shown in the figure, differs from embodiment 1 in that: the screw sleeve 43 is detachably connected with the first connecting arm 1 and the second connecting arm 2. The screw sleeve 43 is detachable, good in controllability and convenient to replace.

Example 3

The child safety seat, as shown in the figure, differs from embodiment 1 in that: all be provided with horizontal sliding block 8 on first linking arm 1 and the second linking arm 2, seted up horizontal sliding groove 7 on the sliding plate 61. When the headrest 6 drives the sliding plate 61 to move upwards or downwards, the sliding plate 61 drives the first connecting arm 1 and the second connecting arm 2 to move upwards or downwards synchronously through the transverse sliding groove 7, and meanwhile, the first connecting arm 1 and the second connecting arm 2 move left and right relatively through the transverse sliding block 8 and the transverse sliding groove 7 to realize left and right movement of the relative sliding plate 61.

Example 4

The child safety seat, as shown in the figure, differs from embodiment 1 in that: the rolling member 5 is formed integrally with the screw 4. The rolling piece 5 and the screw rod 4 are good in synchronism, simple in processing technology and convenient to install and maintain.

Example 5

The child safety seat, as shown in the figure, differs from embodiment 4 in that: the rack and the backrest plate 3 are integrally formed. The rack can be directly arranged on the back plate 3, and the integrated forming design and processing technology is simple and the cost is low.

Example 6

The child safety seat, as shown in the figure, differs from embodiment 5 in that: the rack is detachably connected with the backrest plate 3. The rack can be installed on the back plate 3 alone, and the detachable connection is good in controllability and convenient to replace.

In short, the above description is only a preferred embodiment of the present invention, and all the equivalent changes and modifications made in accordance with the claims of the present invention should be covered by the scope of the present invention.

Claims

1. Child safety seat, including left first linking arm (1), second linking arm (2) on right side and back board (3) of being connected with seat base (9), its characterized in that: the novel connecting device is characterized by further comprising a screw rod (4) used for connecting the first connecting arm (1) and the second connecting arm (2), rolling pieces (5) are arranged on the screw rod (4), a guide transmission part (31) matched with the rolling pieces (5) is arranged on the back plate (3), the screw rod (4) is driven to synchronously rotate when the rolling pieces (5) roll upwards or downwards along the guide transmission part (31), and the screw rod (4) rotates to drive the first connecting arm (1) and the second connecting arm (2) to move oppositely or oppositely.

2. The child safety seat according to claim 1, wherein: the guide transmission part (31) is a rack which is arranged on the backrest plate (3) along the vertical direction, and the rolling part (5) is a gear which is meshed with the rack.

3. The child safety seat according to claim 2, wherein: the rack and the backrest plate (3) are integrally formed or detachably connected.

4. A child safety seat according to claim 1, 2 or 3, wherein: the rolling part (5) and the screw rod (4) are coaxially arranged.

5. The child safety seat according to claim 4, wherein: the rolling piece (5) and the screw rod (4) are integrally formed.

6. The child safety seat according to claim 1, wherein: the first connecting arm (1) and the second connecting arm (2) are respectively provided with a threaded sleeve (43) which is used for being in threaded fit with the screw rod (4), and the threaded sleeves (43) are detachably connected with the first connecting arm (1) and the second connecting arm (2) or integrally formed.

7. The child safety seat according to claim 1, wherein: the screw (4) comprises a first screw section (41) in threaded connection with the first connecting arm (1) and a second screw section (42) in threaded connection with the second connecting arm (2), and the thread directions of the first screw section (41) and the second screw section (42) are opposite.

8. The child safety seat according to claim 7, wherein: the rolling element (5) is arranged in the middle of the screw (4), and the first screw section (41) and the second screw section (42) are respectively positioned on two sides of the rolling element (5).

9. The child safety seat according to claim 1, wherein: the screw rod (4) is arranged along the horizontal direction, the screw thread turning direction of the connecting part of the screw rod (4) and the first connecting arm (1) is right-handed, and the screw thread turning direction of the connecting part of the screw rod (4) and the second connecting arm (2) is left-handed.

10. The child safety seat according to claim 1, wherein: the seat comprises a seat base (9), a left side wing (11), a right side wing (21), a headrest (6), a sliding plate (61) fixedly connected with the headrest (6) and a driving device (62) used for driving the headrest (6) to move up and down, wherein the left side wing (11) is fixedly connected with a first connecting arm (1), the right side wing (21) is fixedly connected with a second connecting arm (2), sliding assemblies are respectively arranged between the first connecting arm (1) and the second connecting arm (2) and the sliding plate (61), each sliding assembly comprises a transverse sliding groove (7) and a transverse sliding block (8), each transverse sliding block (8) is embedded into the corresponding transverse sliding groove (7) and can move left and right relative to the corresponding transverse sliding groove (7), one of the transverse sliding grooves (7) and the transverse sliding blocks (8) is arranged on the first connecting arm (1) and the second connecting arm (2), the other connecting arm is arranged on the sliding plate (61), one end of the driving device (62) is connected with the headrest (6), and the other end of the driving device (62) is connected with the seat base (9).