CN219856887U

CN219856887U - Side wing stretching mechanism and child car seat

Info

Publication number: CN219856887U
Application number: CN202320620374.8U
Authority: CN
Inventors: 侯仁恩
Original assignee: Guangdong Roadmate Group Co Ltd
Current assignee: Guangdong Roadmate Group Co Ltd
Priority date: 2023-03-24
Filing date: 2023-03-24
Publication date: 2023-10-20
Anticipated expiration: 2033-03-24

Abstract

The utility model discloses a side wing stretching mechanism, which comprises a base, a headrest connecting piece, side wings, a stretching mechanism and an automatic adaptive adjusting mechanism, wherein when the headrest moves upwards or downwards relative to the base, the distance between the two side wings is correspondingly increased or reduced through the linkage of the stretching mechanism; if no external force is applied to the side wings, the two reset pressure springs keep balance, and the elastic force of the automatic adaptive adjusting mechanism does not act on the side wings so as to keep the side wings at an initial position; if an external force is applied to the side wings, the side wings can deflect inwards or outwards from the initial positions through the automatic adaptive adjusting mechanism. The utility model also provides a child car seat. The flank stretching mechanism increases the riding height and width and is suitable for children with larger sizes. The riding height and width can be reduced, the child seat is suitable for children with smaller body sizes, and children with different height and body sizes can be accommodated.

Description

Side wing stretching mechanism and child car seat

[ field of technology ]

The utility model relates to the field of infant products, in particular to a flank stretching mechanism and a child car seat.

[ background Art ]

The width of the two sides of the existing child car seat is fixed at present, and the child riding requirements of different height and body types cannot be met.

[ utility model ]

The utility model provides a flank stretching mechanism, which aims to solve the technical problem that the width of two sides of the existing child car seat is fixed and cannot meet the riding requirements of children with different height and body types.

The utility model is realized by the following technical scheme:

a side flap stretching mechanism comprising

The base is provided with a base connecting piece;

the headrest connecting piece is arranged on the base connecting piece and comprises a headrest which moves relative to the base;

the side wings are movably connected to two sides of the headrest connecting piece;

the extension mechanism is used for linking the headrest and the side wings and comprises a pushing component pivoted with the side wings and a limiting component matched with the pushing component, and the limiting component drives the pushing component to move along with the movement of the headrest connecting piece so as to push away or pull back the two side wings;

the automatic adaptation adjusting mechanism is arranged in the telescopic member of the pushing assembly and comprises two reset pressure springs and a propping shaft, the close ends of the two reset pressure springs prop against the propping shaft, and the far ends of the two reset pressure springs respectively prop against the end wall of the inner cavity of the telescopic member;

when the headrest moves upwards or downwards relative to the base, the distance between the two side wings is correspondingly increased or decreased through the linkage of the stretching mechanism;

if no external force is applied to the side wings, the two reset pressure springs keep balance, and the elastic force of the automatic adaptive adjusting mechanism does not act on the side wings so as to keep the side wings at an initial position;

if an external force is applied to the side wings, the side wings can deflect inwards or outwards from the initial positions through the automatic adaptive adjusting mechanism.

The side wing stretching mechanism is used for pushing the side wings to rotate around the movable connection part to the outer side or the inner side of the headrest connecting piece so as to be unfolded or narrowed, wherein each side wing is rotatably connected with the headrest connecting piece around a first longitudinal axis and rotatably connected with the stretching mechanism around a second longitudinal axis, and the first longitudinal axis and the second longitudinal axis are not coaxial.

The side flap extension mechanism as described above,

the pushing component is positioned on the base connecting piece, and when the headrest is adjusted, the pushing component can slide in a longitudinal long groove of the side wing.

A side flap extension mechanism as described above, the headrest connection member and the base connection member together forming a backrest; or the base connecting piece is a backrest.

The side wing stretching mechanism comprises a sliding sleeve in sliding fit with the base connecting piece, and a telescopic piece arranged on the sliding sleeve and pivoted with the side wing, when the side wing is subjected to external force, the telescopic piece is linearly moved relative to the sliding sleeve by the automatic adaptation adjusting mechanism, and when the side wing is not subjected to external force, the telescopic piece is kept fixed relative to the sliding sleeve by the automatic adaptation adjusting mechanism.

The side wing stretching mechanism comprises a limiting component and a pushing component, wherein the limiting component comprises a chute which is arranged on the headrest connecting piece and used for driving one side wing through the pushing component, and the chute extends from the base to the headrest direction and gradually inclines towards the direction close to the other side wing.

According to the side wing stretching mechanism, the long groove is formed in the telescopic piece and matched with the pressing shaft to limit the moving distance of the telescopic piece relative to the sliding sleeve, and when the side wing is pressed, one of the two reset pressure springs is compressed to enable the telescopic piece to move towards the inner side or the outer side of the headrest connecting piece.

The utility model also provides a child car seat, which comprises the side wing stretching mechanism, wherein the headrest connecting piece is in sliding fit with the base connecting piece, and a locking mechanism for limiting the relative position of the headrest connecting piece and the base connecting piece is arranged between the headrest connecting piece and the base connecting piece.

A side flap stretching mechanism comprising

A base on which a seating area is provided;

the backrest is arranged at the rear end of the base and extends upwards and comprises a headrest;

the side wings are arranged on two sides of the backrest and are respectively connected with the backrest in a rotating way around a first longitudinal axis so as to change the width between the two side wings;

an extension mechanism for linking the side wings, comprising a push assembly pivotally connected to the side wings, the push assembly having a telescoping member telescoping relative to the backrest, rotatably connected to the side wings by a second longitudinal axis;

the automatic adaptation adjusting mechanism is arranged in the telescopic member of the pushing assembly and comprises two reset pressure springs and a pressing shaft, wherein the adjacent ends of the two reset pressure springs are pressed against the pressing shaft, and the far ends of the two reset pressure springs are respectively pressed against the backrest and the inner cavity end wall of the telescopic member;

if no external force is applied to the side wings, the two reset pressure springs keep balance, and the elastic force of the automatic adaptive adjusting mechanism does not act on the side wings, so that the side wings are kept at an initial position; if an external force is applied to the side wings, the side wings can deflect inwards or outwards from the initial positions through the automatic adaptive adjusting mechanism.

According to the side wing stretching mechanism, the telescopic member is a telescopic piece, when the side wings are not subjected to external force, the telescopic piece is kept fixed relative to the backrest by the automatic adaptation adjusting mechanism, and when the side wings are subjected to external force, the telescopic piece is moved relative to the backrest by the automatic adaptation adjusting mechanism.

According to the flank stretching mechanism, the two reset pressure springs are combined into one pressure spring, the pressing shaft is arranged in the middle section of the pressure spring, and the two outer ends of the pressing shaft are respectively pressed against the backrest and the telescopic piece.

The side wing stretching mechanism as described above, the backrest includes a headrest link having a headrest and a base link slidably coupled to the headrest link.

The side wing stretching mechanism comprises the base connecting piece, the telescopic component and the sliding sleeve, wherein the sliding sleeve is fixed on the base connecting piece, the chute is arranged on the headrest connecting piece, and when the headrest moves upwards or downwards relative to the base, the sliding sleeve can slide in the chute, so that the distance between the two side wings is correspondingly increased or reduced.

Compared with the prior art, the utility model has the following advantages:

according to the side wing stretching mechanism, the headrest and the side wings are linked through the stretching mechanism, when the side wing stretching mechanism is used, the headrest moves in the direction away from the base, the distance between the two side wings is increased for stretching, so that the riding height and the riding width are increased, and the side wing stretching mechanism is suitable for riding older or older children. The headrest can be moved towards the direction close to the base, so that the distance between the two side wings is reduced for narrowing, and the riding height and width are reduced, so that the headrest is suitable for children with smaller ages or sizes. The effect of adapting to children with different height and body types is achieved. Further, in the process of adjusting the height of the headrest, or before and after adjustment, the side wings are at a height, if the side wings are not stressed, the side wings are kept at the initial positions, if the outside is stressed, namely, when a plurality of child car seats or car seat spaces are narrower in the car, the side wings can deflect inwards through the automatic adaptation adjusting structure to reduce the space, otherwise, if the inside is stressed, namely, when a child is fat, the side wings can deflect outwards through the automatic adaptation adjusting structure to reduce the compression on the child. In particular, the wing stretching mechanism can be applied to child products such as child car seats, carts and the like.

[ description of the drawings ]

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic view of the developed state of the present embodiment;

FIG. 2 is an exploded view of the structure of FIG. 1;

FIG. 3 is a cross-sectional view at A-A of FIG. 1;

FIG. 4 is an enlarged view at B of FIG. 3;

fig. 5 is a schematic view of the narrowing state of the present embodiment;

FIG. 6 is a schematic view of the narrowed state of FIG. 4;

FIG. 7 is a schematic view showing the internal structure of the side flaps when the side flaps are not under force;

FIG. 8 is a schematic view showing the internal structure of the side flap of FIG. 7 when the inside of the side flap is subjected to a force;

fig. 9 is a schematic view showing the internal structure of the side flap of fig. 7 when the outer side of the side flap is forced.

[ detailed description ] of the utility model

In order to make the technical scheme and beneficial effects of the technical problem solved by the utility model more clear, the utility model is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the utility model.

Embodiment one: a side flap stretching mechanism comprising

A base 1, on which a base connector 2 is provided;

a headrest connector 3 provided on the base connector 2, the headrest connector 3 including a headrest 5 which moves relative to the base 1;

the side wings 4 are movably connected to the two sides of the headrest connecting piece 3;

an extension mechanism 6 for linking the headrest 5 and the side wings 4, comprising a pushing component 61 pivoted with the side wings 4 and a limiting component 62 matched with the pushing component 61, wherein the limiting component 62 drives the pushing component 61 to move along with the movement of the headrest connecting piece 3 so as to push or pull the two side wings 4;

the automatic adaptation adjusting mechanism 7 is arranged in the telescopic member of the pushing assembly 61 and comprises two reset pressure springs 71 and a pressing shaft 72, the close ends of the two reset pressure springs 71 are pressed against the pressing shaft 72, and the opposite ends are respectively pressed against the end wall of the inner cavity of the telescopic member;

when the headrest 5 moves upwards or downwards relative to the base 1, the distance between the two side wings 4 is correspondingly increased or decreased through the linkage of the stretching mechanism 6;

if no external force is applied to the side wing 4, the two return compression springs 71 keep balance, and the elastic force of the self-adaptive adjusting mechanism 7 does not act on the side wing 4, so that the side wing 4 is kept at an initial position;

if an external force is applied to the side wing 4, the side wing 4 can swing inwards or outwards from the initial position through the self-adaptive adjusting mechanism 7.

Further, as a preferred embodiment of the present utility model, but not limited to, the extension mechanism 6 is configured to push the side wings 4 to rotate around the movable connection to the outside or inside of the headrest connector 3 for deployment or contraction, where each side wing 4 is rotatably connected to the headrest connector 3 around a first longitudinal axis, and is rotatably connected to the extension mechanism 6 around a second longitudinal axis, and the first longitudinal axis and the second longitudinal axis are not coaxial. In this embodiment, the two side wings are respectively on two sides of the headrest connection member. In this embodiment, the distance between the two side wings is adjusted by rotating the side wings relative to the headrest connecting piece. The distance can also be adjusted by pushing the two side wings away from or towards each other.

Further, as a preferred embodiment of the present utility model, but not limited to, a hinge portion 41 is provided between the side wing 4 and the headrest connector 3, and the hinge portion 41 is hinged to the headrest connector 3, so that the side wing 4 can rotate relative to the headrest connector 3 for unfolding or narrowing. Specifically, the hinge part rotates relative to the headrest connecting piece, so that the side wings rotate around the hinge part of the hinge part and the headrest connecting piece, and the distance between the two side wings is adjusted to be unfolded or narrowed.

Further, as a preferred embodiment of the present utility model and not by way of limitation, the pushing assembly 61 is located on the base connector 2, and the pushing assembly 61 is slidably disposed in a longitudinal slot of the side wing 4 when the headrest 5 is adjusted. Specifically, the longitudinal slot 43 functions to maintain the push assembly in a connected relationship with the side wings as the side wings are raised or lowered with the headrest.

Further, as a preferred embodiment of the present solution, not by way of limitation, the headrest connection member 3 and the base connection member 2 together form a backrest; or the base connector 2 is a backrest.

Further, as a preferred embodiment of the present utility model, but not limited to, the pushing assembly 61 includes a sliding sleeve 611 slidably engaged with the base connecting member 2, and a telescopic member 612 pivotally connected to the side wing 4 and provided on the sliding sleeve 611, when the side wing 4 is subjected to an external force, the self-adapting adjusting mechanism 7 allows the telescopic member 612 to move relative to the sliding sleeve 611, and when the side wing 4 is not subjected to an external force, the self-adapting adjusting mechanism 7 allows the telescopic member 612 to remain fixed relative to the sliding sleeve 611. As shown in fig. 8 and 9, the side wings are biased by the self-adaptive adjustment mechanism when being stressed. When the side wings are not subjected to external force, the side wings move to the adjusting positions along with the driving of the stretching mechanism, and when the inner sides of the side wings are stressed, the side wings can be outwards stretched, so that the compression to children is avoided. When the outer sides of the side wings are stressed, the side wings can be narrowed inwards, and the automobile seat is suitable for use environments with narrow space, such as when three automobile seats are placed on an automobile back row seat, the space is insufficient, and the side wings can be narrowed inwards to give way.

Further, as a preferred embodiment of the present utility model, but not limited thereto, the limiting assembly 62 includes a chute 621 provided on the headrest connector 3 for driving one of the side wings 4 by the pushing assembly 61, and the chute 621 extends from the base 1 toward the headrest 5 and gradually inclines toward the other side wing 4. The chute is matched with the sliding sleeve, and when the headrest connecting piece moves, the chute moves to push the sliding movement. In this embodiment, there are two inclined slots, which can drive both flanks simultaneously.

Further, as a preferred embodiment of the present utility model, but not limited to, the telescopic member 612 is provided with a long groove 614, the long groove 614 cooperates with the pressing shaft 72 to limit the moving distance of the telescopic member 612 relative to the sliding sleeve 611, and when the side wing 4 is pressed, one of the two restoring compression springs 71 is compressed, so that the telescopic member 612 moves toward the inner side or the outer side of the headrest connecting member 3. Through the scheme, the telescopic piece is positioned in the middle of the long groove under the condition of not receiving external force, namely the side wing can slide along the long groove when being stressed by external force, so that the side wing can be unfolded or narrowed relative to the adjusting position, and the side wing is restored when the external force is withdrawn.

The child car seat comprises the side wing stretching mechanism, wherein the headrest connecting piece 3 is in sliding fit with the base connecting piece 2, and a locking mechanism 8 for limiting the relative position of the headrest connecting piece and the base connecting piece is arranged between the headrest connecting piece and the base connecting piece.

Embodiment two: a side flap stretching mechanism comprising

A base 1 on which a seating area is provided;

the backrest is arranged at the rear end of the base 1 and extends upwards and comprises a headrest 5;

the side wings 4 are arranged on two sides of the backrest and are respectively connected with the backrest in a rotating way around a first longitudinal axis so as to change the width between the two side wings 4;

an extension mechanism 6 for linking the side wings 4, comprising a pushing assembly 61 pivotally connected to the side wings 4, the pushing assembly 61 having a telescopic member which is telescopic with respect to the backrest and which is rotatably connected to the side wings 4 by a second longitudinal axis;

the automatic adaptation adjusting mechanism 7 is arranged in the telescopic member of the pushing assembly 61 and comprises two reset pressure springs 71 and a pressing shaft 72, wherein the adjacent ends of the two reset pressure springs 71 are pressed against the pressing shaft 72, and the opposite distal ends are respectively pressed against the backrest and the inner cavity end wall of the telescopic member;

when no external force is applied to the side wing 4, the two return compression springs 71 keep balance, and the elastic force of the automatic adaptive adjusting mechanism 7 does not act on the side wing 4, so that the side wing 4 is kept at an initial position; if an external force is applied to the side wing 4, the side wing 4 can swing inwards or outwards from the initial position through the self-adaptive adjusting mechanism 7.

Further, as a preferred embodiment of the present embodiment, not by way of limitation, the headrest 5 moves up and down with respect to the base 1.

Further, as a preferred embodiment of the present utility model, but not limited to, the telescopic member is a telescopic member 612, the self-adaptive adjusting mechanism 7 is used for keeping the telescopic member 612 fixed relative to the backrest when the lateral wing 4 is not subjected to external force, and the self-adaptive adjusting mechanism 7 is used for moving the telescopic member 612 relative to the backrest when the lateral wing 4 is subjected to external force.

Further, as a preferred embodiment of the present utility model, but not limited to, the two restoring compression springs 71 are combined into a compression spring, the pressing shaft 72 is disposed in the middle section of the compression spring, and two outer ends respectively press against the backrest and the expansion member 612.

Further, as a preferred embodiment of the present solution, but not limiting, the backrest comprises a headrest connector 3 having a headrest and a base connector 2 slidably connected with the headrest connector 3.

Further, as a preferred embodiment of the present utility model, but not limited to, the sliding sleeve 611 fixed to the base connector 2 and the chute 621 provided on the headrest connector 3 are further included between the base connector 2 and the telescopic member, and when the headrest 5 moves up or down relative to the base 1, the sliding sleeve 611 can slide in the chute 621, so that the space between the two side wings 4 increases or decreases accordingly.

The working principle of this embodiment is as follows:

in use, if no external force is applied to the side wing 4, the two return compression springs 71 remain balanced, and the elastic force of the automatic adaptive adjustment mechanism 7 does not act on the side wing 4, so that the side wing 4 is kept at an initial position; if an external force is applied to the side wings 4, the side wings 4 may be deflected inwardly or outwardly from the initial position by the self-adapting adjustment mechanism 7 in the telescopic member. Further, if the side wings are required to be matched with the headrest for unfolding, the headrest is improved, and when the headrest ascends, the chute drives the sliding sleeve to move outwards, so that the telescopic piece pushes the hinge part to rotate, and finally the side wings are outwards unfolded; conversely, if the side wings are required to be matched with the headrest for narrowing, the lower pressing head is leaned, and when the headrest descends, the chute drives the sliding sleeve to move inwards, so that the telescopic piece pushes the hinge part to rotate, and finally the side wings are narrowed inwards.

The embodiments provided above in connection with the specific disclosure are not intended to limit the practice of the utility model to those descriptions. The present utility model should be considered as the protection scope of the present utility model, if the structure of the method is similar to that of the present utility model, or if several technical deductions or substitutions are made on the premise of the present utility model.

Claims

1. The flank extends mechanism, its characterized in that: comprising

A base (1) on which a base connecting piece (2) is arranged;

a headrest connector (3) provided on the base connector (2), the headrest connector (3) including a headrest (5) which moves relative to the base (1);

the side wings (4) are movably connected to the two sides of the headrest connecting piece (3);

-an extension mechanism (6) for linking the headrest (5) and the side wings (4), comprising a pushing assembly (61) pivotally connected to the side wings (4), and a limiting assembly (62) cooperating with the pushing assembly (61), the limiting assembly (62) driving the pushing assembly (61) to move along with the movement of the headrest connector (3) to push or pull back the two side wings (4);

the automatic adaptation adjusting mechanism (7) is arranged in the telescopic member of the pushing assembly (61) and comprises two reset pressure springs (71) and a pressing shaft (72), the close ends of the two reset pressure springs (71) are pressed against the pressing shaft (72), and the opposite ends of the two reset pressure springs are respectively pressed against the end wall of the inner cavity of the telescopic member;

when the headrest (5) moves upwards or downwards relative to the base (1), the distance between the two side wings (4) is correspondingly increased or decreased through the linkage of the stretching mechanism (6);

if no external force is applied to the side wings (4), the two reset compression springs (71) keep balance, and the elastic force of the automatic adaptive adjusting mechanism (7) does not act on the side wings (4) so as to keep the side wings (4) at an initial position;

when an external force is applied to the side wings (4), the side wings (4) can deflect inwards or outwards from the initial position through the automatic adaptive adjusting mechanism (7).

2. The flap extension mechanism of claim 1, wherein: the stretching mechanism (6) is used for pushing the side wings (4) to rotate around the movable connection part to the outer side or the inner side of the headrest connecting piece (3) so as to be unfolded or narrowed, wherein each side wing (4) is rotatably connected with the headrest connecting piece (3) around a first longitudinal axis and rotatably connected with the stretching mechanism (6) around a second longitudinal axis, and the first longitudinal axis and the second longitudinal axis are not coaxial.

3. The flap extension mechanism of claim 1, wherein:

the pushing component (61) is positioned on the base connecting piece (2), and when the headrest (5) is adjusted, the pushing component (61) can slide in a longitudinal long groove of the side wing (4).

4. The flap extension mechanism of claim 1, wherein: the headrest connecting piece (3) and the base connecting piece (2) form a backrest together; or the base connecting piece (2) is a backrest.

5. The flap extension mechanism of claim 1, wherein: the pushing assembly (61) comprises a sliding sleeve (611) in sliding fit with the base connecting piece (2), and a telescopic piece (612) which is arranged on the sliding sleeve (611) and pivoted with the side wing (4), when the side wing (4) is subjected to external force, the telescopic piece (612) is linearly moved relative to the sliding sleeve (611) by the automatic adaptation adjusting mechanism (7), and when the side wing (4) is not subjected to external force, the telescopic piece (612) is kept fixed relative to the sliding sleeve (611) by the automatic adaptation adjusting mechanism (7).

6. The flap extension mechanism of claim 1, wherein: the limiting component (62) comprises a chute (621) which is arranged on the headrest connecting piece (3) and is used for driving one side wing (4) through the pushing component (61), and the chute (621) extends from the base (1) to the direction of the headrest (5) and gradually inclines to the direction close to the other side wing (4).

7. The flap extension mechanism of claim 5, wherein: the telescopic piece (612) is provided with a long groove (614), the long groove (614) is matched with the pressing shaft (72) to limit the moving distance of the telescopic piece (612) relative to the sliding sleeve (611), and when the side wing (4) is pressed, one of the two reset pressure springs (71) is compressed to enable the telescopic piece (612) to move towards the inner side or the outer side of the headrest connecting piece (3).

8. Child car seat, its characterized in that: comprising a wing stretching mechanism according to any one of claims 1 to 7, wherein the headrest connector (3) is in sliding fit with the base connector (2) and a locking mechanism (8) is arranged between the headrest connector and the base connector for limiting the relative position of the headrest connector and the base connector.

9. The flank extends mechanism, its characterized in that: comprising

A base (1) provided with a seating area;

the backrest is arranged at the rear end of the base (1) and extends upwards and comprises a headrest (5);

the side wings (4) are arranged on two sides of the backrest and are respectively connected with the backrest in a rotating way around a first longitudinal axis so as to change the width between the two side wings (4);

-an extension mechanism (6) for linking the side wings (4), comprising a pushing assembly (61) pivotally connected to the side wings (4), the pushing assembly (61) having a telescopic member which is telescopic with respect to the backrest and which is rotatably connected to the side wings (4) by a second longitudinal axis;

the automatic adaptation adjusting mechanism (7) is arranged in the telescopic member of the pushing assembly (61) and comprises two reset pressure springs (71) and a pressing shaft (72), wherein the adjacent ends of the two reset pressure springs (71) are pressed against the pressing shaft (72), and the opposite distal ends are respectively pressed against the backrest and the inner cavity end wall of the telescopic member;

when no external force is applied to the side wings (4), the two reset compression springs (71) keep balance, and the elastic force of the automatic adaptive adjusting mechanism (7) does not act on the side wings (4) so as to keep the side wings (4) at an initial position; when an external force is applied to the side wings (4), the side wings (4) can deflect inwards or outwards from the initial position through the automatic adaptive adjusting mechanism (7).

10. The flap extension mechanism of claim 9, wherein: the telescopic member is a telescopic piece (612), when the side wing (4) is not subjected to external force, the telescopic piece (612) is kept fixed relative to the backrest by the automatic adaptation adjusting mechanism (7), and when the side wing (4) is subjected to external force, the telescopic piece (612) is moved relative to the backrest by the automatic adaptation adjusting mechanism (7).

11. The flap extension mechanism of claim 10, wherein: the two reset compression springs (71) are combined into a compression spring, the pressing shaft (72) is arranged at the middle section of the compression spring, and the two outer ends are respectively pressed against the backrest and the telescopic piece (612).

12. The flap extension mechanism of claim 9, wherein: the backrest comprises a headrest connecting piece (3) with a headrest and a base connecting piece (2) which is connected with the headrest connecting piece (3) in a sliding way.

13. The flap extension mechanism of claim 12, wherein: the telescopic device is characterized in that a sliding sleeve (611) fixed on the base connecting piece (2) and a chute (621) arranged on the headrest connecting piece (3) are further arranged between the base connecting piece (2) and the telescopic member, and when the headrest (5) moves upwards or downwards relative to the base (1), the sliding sleeve (611) can slide in the chute (621), so that the distance between the two side wings (4) is correspondingly increased or decreased.