Ratchet mechanism, table board structure and automobile seat

Abstract

A ratchet mechanism, a table structure, and a car seat are disclosed. The ratchet mechanism includes a fixedly mounted first ratchet, a rotatable second ratchet, and a clutch assembly. The clutch assembly includes a separating plate and a clamping member. The separating plate is rotatably mounted on the first ratchet, and the clamping member is fixed to the second ratchet. The separating plate has a first abutment surface and a second abutment surface. Rotation of the second ratchet can cause the clamping member to abut against either the first or second abutment surface. When the clamping member abuts against the first abutment surface, the first and second ratchets are in a meshing state; when the clamping member abuts against the second abutment surface, the first and second ratchets are in a disengaged state. In this application, the clutch assembly allows the first and second ratchets to switch between meshing and disengaging states, realizing a bidirectional adjustment function of the ratchet mechanism. The limiting effect of the first and second ratchets ensures that the table will not fall after being suspended, and it is adjustable in multiple positions for convenient use.

Description

Technical Field

[0001] This application relates to the field of automotive seat technology, specifically to a ratchet mechanism, a table structure, and an automotive seat. Background Technology

[0002] With the development of the automotive industry, people have placed higher demands on the comfort and functionality of car interiors. In car seat design, the user experience of rear passengers is receiving increasing attention, and the tray table structure on the back of the seatback is one of the important features for improving rear passenger comfort. Small tray tables are conveniently located on the back of car seats for rear passengers. These tray tables are generally foldable; they are unfolded downwards when needed and folded upwards to the back of the seatback when not in use.

[0003] In existing technologies, the table structure on the back of car seat backs uses a ratchet mechanism to adjust the angle and fix the position of the table. However, it has few gears (usually only 2 to 5), limiting its applicability. When the front seat back is not in the designed position, the table angle will deviate from horizontal, causing inconvenience for rear passengers. In addition, existing ratchet mechanisms are often structurally complex with many parts, increasing manufacturing costs and failure rates. Utility Model Content

[0004] The purpose of this application is to provide a ratchet mechanism, a table structure, and an automobile seat to solve the problems of limited manual adjustment table positions and complex ratchet mechanism structures in existing manual adjustment tables.

[0005] To achieve the objectives of this application, the following technical solution is provided:

[0006] In the first aspect, this application provides a ratchet mechanism, including:

[0007] The first ratchet is fixed in place;

[0008] A rotatable second ratchet;

[0009] A clutch assembly includes a release plate and a clamping member. The release plate is rotatably disposed on a first ratchet, and the clamping member is fixed to a second ratchet. The release plate has a first abutting surface and a second abutting surface. Rotation of the second ratchet can drive the clamping member to abut against the first abutting surface or the second abutting surface.

[0010] When the clamping member abuts against the first contact surface, the first ratchet and the second ratchet are in a mutually engaged state; when the clamping member abuts against the second contact surface, the first ratchet and the second ratchet are in a disengaged state.

[0011] In one embodiment, the end face of the first ratchet near the second ratchet is the first end face, the end face of the second ratchet near the first ratchet is the second end face, the separating plate is disposed on the first end face, and the clamping member protrudes from the second end face;

[0012] The distance between the first abutting surface and the second end surface is greater than the distance between the second abutting surface and the second end surface.

[0013] In one embodiment, the ratchet mechanism further includes a fixed shaft, with a hole on the first end face and a slot on the second end face, the fixed shaft being inserted into the hole and the slot;

[0014] The separating plate is sleeved on the fixed shaft, the first abutting surface and the second abutting surface are arranged sequentially in the circumferential direction of the fixed shaft, and the clamping member is located on the outer side of the slot along the axial direction.

[0015] In one embodiment, the separating piece is further provided with a guide arc surface, which is connected between the first abutting surface and the second abutting surface, and the clamping member can abut against the guide arc surface.

[0016] In one embodiment, a limiting protrusion is provided on the first end face, and a limiting groove is formed on the separating piece, with the limiting protrusion disposed in the limiting groove;

[0017] The limiting groove includes a first limiting surface and a second limiting surface that are spaced apart. In the circumferential direction of the fixed shaft, the distance between the first limiting surface and the second limiting surface is greater than the width of the limiting protrusion. The limiting protrusion can abut against the first limiting surface or the second limiting surface.

[0018] When the limiting protrusion abuts against the first limiting surface, the clamping member abuts against the second abutting surface in sequence along the first abutting surface and the guide arc surface;

[0019] When the limiting protrusion abuts against the second limiting surface, the clamping member abuts against the first abutting surface in sequence along the second abutting surface and the guide arc surface.

[0020] In one embodiment, the clutch assembly further includes a gasket disposed between the first end face and the separation plate, the gasket having a slot that engages with the limiting protrusion.

[0021] In one embodiment, the ratchet mechanism further includes a mounting bracket and an elastic element. The first ratchet is fixed on the mounting bracket, and a rotating shaft is connected to the outer wall of one end of the second ratchet along the axial direction. The rotating shaft is rotatably connected to the mounting bracket. The elastic element is sleeved on the rotating shaft, and one end of the elastic element abuts against the mounting bracket, while the other end of the elastic element abuts against the outer wall of the second ratchet.

[0022] In one embodiment, the mounting bracket includes a first mounting plate, a second mounting plate, and a third mounting plate connected in sequence, wherein the first mounting plate and the third mounting plate both extend axially along the fixed shaft, and the second mounting plate extends radially along the fixed shaft.

[0023] The second mounting plate is provided with mounting holes, and the rotating shaft is inserted into the mounting holes.

[0024] Secondly, this application also provides a table structure disposed on the back side of a car seat backrest, the table structure including a table and a ratchet mechanism as described in any of the various embodiments of the first aspect, wherein the first ratchet is connected to the backrest and the second ratchet is connected to the table;

[0025] The tabletop has an unfolded position and a folded position on the back side of the backrest, and the tabletop can move between the unfolded position and the folded position;

[0026] When the tabletop moves from top to bottom to the unfolded position, the first ratchet and the second ratchet are engaged with each other. The user can manually adjust the hovering position of the tabletop upwards, and the first ratchet and the second ratchet restrict the downward movement of the tabletop so that the tabletop is hovered at the position adjusted by the user.

[0027] Thirdly, this application also provides an automobile seat, including a seat portion, a backrest, and the table structure described in the second aspect, wherein the backrest is rotatably disposed on the seat portion, and the table structure is connected to the back side of the backrest.

[0028] Compared with the prior art, this application has at least the following beneficial effects:

[0029] 1. In this application, the ratchet mechanism, by incorporating a clutch component, allows the first and second ratchet wheels to switch between an engaged state and a disengaged state, thus achieving a bidirectional adjustment function. When the clamping member abuts against the first contact surface, the first and second ratchet wheels are engaged, and the second ratchet wheel can only rotate in one direction. When the clamping member abuts against the second contact surface, the first and second ratchet wheels are disengaged, and the second ratchet wheel can rotate freely.

[0030] 2. In this application, the ratchet mechanism consists of a first ratchet, a second ratchet, a clutch assembly, etc. It achieves the switching between engagement and disengagement states by changing the contact between the clamping part and different contact surfaces. The structure is relatively simple, with fewer parts, which reduces manufacturing costs and maintenance difficulty, reduces the possibility of failure, and improves the reliability of the mechanism.

[0031] 3. In this application, a ratchet mechanism is applied to the tabletop structure. The tabletop is movably mounted on the back of the seat back via the ratchet mechanism. When the user switches the tabletop to the unfolded position from top to bottom, the first ratchet and the second ratchet are engaged. At this time, the first ratchet and the second ratchet restrict the tabletop to move in only one direction, that is, the tabletop can rotate upwards but cannot rotate downwards. The user can rotate the tabletop upwards according to their own needs to adjust the hovering position of the tabletop, that is, manually hover the tabletop. Due to the limiting effect of the first ratchet and the second ratchet, it is ensured that the tabletop will not fall after being hovered. It is adjustable in multiple positions, convenient to use, and can be operated by the user with one hand. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0033] Figure 1 This is a perspective view of a ratchet mechanism according to one embodiment of this application;

[0034] Figure 2 This is a top view of a ratchet mechanism according to one embodiment of this application;

[0035] Figure 3 for Figure 2 Sectional view of AA;

[0036] Figure 4 This is an exploded view of a ratchet mechanism according to one embodiment of this application;

[0037] Figure 5 This is another exploded view of a ratchet mechanism according to one embodiment of this application;

[0038] Figure 6 This is an exploded view of a portion of the ratchet mechanism according to one embodiment of this application;

[0039] Figure 7 This is a perspective view of a separation sheet according to one embodiment of this application.

[0040] Explanation of reference numerals in the attached figures:

[0041] 100, First ratchet; 110, First end face; 111, Insertion hole; 112, Limiting protrusion; 200, Second ratchet; 210, Second end face; 211, Slot; 220, Rotating shaft; 221, Notch; 300, Clutch assembly; 310, Separator plate; 311, First abutment surface; 312, Second abutment surface; 313, Guide arc surface; 314, Limiting groove; 314a, First limiting surface; 314b, Second limiting surface; 320, Clamping element; 330, Gasket; 331, Slot; 400, Fixed shaft; 500, Mounting bracket; 510, First mounting plate; 520, Second mounting plate; 521, Mounting hole; 530, Third mounting plate; 600, Elastic element. Detailed Implementation

[0042] The following are specific embodiments of this application, which are described in conjunction with the accompanying drawings to further illustrate the technical solutions of this application. However, this application is not limited to these embodiments.

[0043] refer to Figures 1-7 This application provides a ratchet mechanism, including a fixedly mounted first ratchet 100, a rotatable second ratchet 200, and a clutch assembly 300. The clutch assembly 300 includes a separating plate 310 and a clamping member 320. The separating plate 310 is rotatably mounted on the first ratchet 100, and the clamping member 320 is fixed to the second ratchet 200. The separating plate 310 has a first abutting surface 311 and a second abutting surface 312. Rotation of the second ratchet 200 can drive the clamping member 320 to abut against the first abutting surface 311 or the second abutting surface 312. When the clamping member 320 abuts against the first abutting surface 311, the first ratchet 100 and the second ratchet 200 are in a mutually engaged state; when the clamping member 320 abuts against the second abutting surface 312, the first ratchet 100 and the second ratchet 200 are in a disengaged state.

[0044] In this embodiment, the ratchet mechanism, by incorporating a clutch component 300, allows the first ratchet 100 and the second ratchet 200 to switch between an engaged state and a disengaged state, thus achieving a bidirectional adjustment function. When the clamping member 320 abuts against the first contact surface 311, the first ratchet 100 and the second ratchet 200 are in an engaged state, at which point the second ratchet 200 can only rotate in one direction. When the clamping member 320 abuts against the second contact surface 312, the first ratchet 100 and the second ratchet 200 are in a disengaged state, at which point the second ratchet 200 can rotate freely.

[0045] In this embodiment, both the first ratchet 100 and the second ratchet 200 are ratchet structures. The ratchet teeth of the first ratchet 100 match the ratchet teeth of the second ratchet 200, allowing them to mesh with each other. The first ratchet 100 is fixed, while the second ratchet 200 can rotate. The separating plate 310 has a fan-shaped structure, and its end face is provided with a first abutment surface 311 and a second abutment surface 312. The clamping member 320 has a protrusion structure and is fixed to the second ratchet 200, rotating as the second ratchet 200 rotates.

[0046] When the second ratchet 200 rotates, the clamping member 320 rotates accordingly and abuts against the first contact surface 311 or the second contact surface 312 of the separating piece 310. When the clamping member 320 abuts against the first contact surface 311, the first ratchet 100 and the second ratchet 200 mesh together, and the separating piece 310 rotates together with the clamping member 320 to one position; when the clamping member 320 abuts against the second contact surface 312, the first ratchet 100 and the second ratchet 200 disengage, and the separating piece 310 rotates together with the clamping member 320 to another position.

[0047] Wherein, the end face of the first ratchet 100 near the second ratchet 200 is the first end face 110, the end face of the second ratchet 200 near the first ratchet 100 is the second end face 210, the separating piece 310 is disposed on the first end face 110, and the clamping member 320 protrudes from the second end face 210; the distance between the first abutting surface 311 and the second end face 210 is greater than the distance between the second abutting surface 312 and the second end face 210. Specifically, the separating plate 310 and at least part of the clamping member 320 are disposed between the first end face 110 and the second end face 210. The ratchet teeth on the first ratchet 100 are disposed on the first end face 110 and are located around the separating plate 310. The ratchet teeth on the second ratchet 200 are disposed on the second end face 210 and are located around the clamping member 320. By abutting the clamping member 320 against the first abutting surface 311 or the second abutting surface 312 on the separating plate 310, the engagement or disengagement of the first ratchet 100 and the second ratchet 200 can be realized, which simplifies the structure of the ratchet mechanism.

[0048] The ratchet mechanism also includes a fixed shaft 400. A first end face 110 has a socket 111, and a second end face 210 has a slot 211. The fixed shaft 400 is inserted into the socket 111 and the slot 211. A separating piece 310 is sleeved on the fixed shaft 400. A first abutment surface 311 and a second abutment surface 312 are sequentially arranged circumferentially on the fixed shaft 400. A clamping member 320 is located axially outside the slot 211. Specifically, the separating piece 310 has a through hole at its center, which is sleeved on the fixed shaft 400, allowing the separating piece 310 to rotate around the fixed shaft 400. Simultaneously, the fixed shaft 400, inserted into the socket 111 of the first end face 110 and the slot 211 of the second end face 210, provides a common axis of rotation for the first ratchet 100 and the second ratchet 200. The first abutment surface 311 and the second abutment surface 312 are arranged sequentially in the circumferential direction of the fixed shaft 400, so that the clamping member 320 can abut against them in sequence. The clamping member 320 is located on the outer side of the slot 211 along the axial direction. This design allows the clamping member 320 to fully contact the first abutment surface 311 and the second abutment surface 312 of the separating piece 310.

[0049] The separating plate 310 is also provided with a guide arc surface 313, which connects the first abutment surface 311 and the second abutment surface 312. The clamping member 320 can abut against the guide arc surface 313. The first abutment surface 311 and the second abutment surface 312 are connected by the guide arc surface 313 to form an arc transition surface between the first abutment surface 311 and the second abutment surface 312. The guide arc surface 313 can guide the clamping member 320 to transition smoothly, so that the clamping member 320 can move smoothly between the first abutment surface 311 and the second abutment surface 312.

[0050] refer to Figure 5 , Figure 6 and Figure 7 The first end face 110 is provided with a limiting protrusion 112, and the separating plate 310 is provided with a limiting groove 314, in which the limiting protrusion 112 is disposed. The limiting groove 314 includes a first limiting surface 314a and a second limiting surface 314b spaced apart. In the circumferential direction of the fixed shaft 400, the distance between the first limiting surface 314a and the second limiting surface 314b is greater than the width of the limiting protrusion 112, and the limiting protrusion 112 can interact with the limiting surface 112. The first limiting surface 314a or the second limiting surface 314b abuts against each other; when the limiting protrusion 112 abuts against the first limiting surface 314a, the clamping member 320 abuts against the second abutting surface 312 in sequence along the first abutting surface 311 and the guide arc surface 313; when the limiting protrusion 112 abuts against the second limiting surface 314b, the clamping member 320 abuts against the first abutting surface 311 in sequence along the second abutting surface 312 and the guide arc surface 313.

[0051] Specifically, the design of the limiting protrusion 112 and the limiting groove 314 restricts the rotation range of the separating piece 310, preventing excessive rotation. The limiting groove 314 includes a first limiting surface 314a and a second limiting surface 314b spaced apart. The limiting protrusion 112 can abut against either the first limiting surface 314a or the second limiting surface 314b, thereby limiting the rotation range of the separating piece 310. When the limiting protrusion 112 abuts against the first limiting surface 314a, the clamping member 320 will abut against the second abutting surface 312 along the first abutting surface 311 and the guide arc surface 313 in sequence, at which time the second ratchet 200 can rotate freely; when the limiting protrusion 112 abuts against the second limiting surface 314b, the clamping member 320 will abut against the first abutting surface 311 along the second abutting surface 312 and the guide arc surface 313 in sequence, at which time the second ratchet 200 can only rotate in one direction.

[0052] The clutch assembly 300 also includes a gasket 330, which is disposed between the first end face 110 and the separator plate 310. The gasket 330 has a groove 331 that engages with the limiting protrusion 112. The gasket 330 is disposed between the first end face 110 and the separator plate 310 to reduce friction and protect the separator plate 310. The groove 331 on the gasket 330 engages with the limiting protrusion 112, so that the gasket 330 can be fixed on the first end face 110 and will not rotate with the rotation of the separator plate 310.

[0053] The ratchet mechanism also includes a mounting bracket 500 and an elastic element 600. A first ratchet 100 is fixed to the mounting bracket 500. A rotating shaft 220 is connected to the outer wall of one axial end of the second ratchet 200. The rotating shaft 220 is rotatably connected to the mounting bracket 500. The elastic element 600 is sleeved on the rotating shaft 220, with one end of the elastic element 600 abutting against the mounting bracket 500 and the other end abutting against the outer wall of the second ratchet 200. The mounting bracket 500 provides a support and fixing structure for the first ratchet 100 and the second ratchet 200. The first ratchet 100 is fixed to the mounting bracket 500 and remains stationary; the second ratchet 200 is rotatably connected to the mounting bracket 500 via the rotating shaft 220 and can rotate freely. The elastic element 600 is sleeved on the rotating shaft 220, with one end abutting against the mounting bracket 500 and the other end abutting against the outer wall of the second ratchet 200, providing a rebound force for the second ratchet 200 and a clamping force for the clamping element 320 to press against the separating plate 310.

[0054] The mounting bracket 500 includes a first mounting plate 510, a second mounting plate 520, and a third mounting plate 530 connected in sequence. The first mounting plate 510 and the third mounting plate 530 both extend axially along the fixed shaft 400, while the second mounting plate 520 extends radially along the fixed shaft 400, allowing the mounting bracket 500 to securely support the first ratchet 100 and the second ratchet 200. The second mounting plate 520 has a mounting hole 521, into which a rotating shaft 220 is inserted, allowing the second ratchet 200 to rotate around the rotating shaft 220.

[0055] The ratchet mechanism in this embodiment has a simple structure, is easy to operate, and can achieve bidirectional adjustment, making it suitable for various occasions where angle or position adjustment is required.

[0056] This application provides a table structure disposed on the back side of a car seat backrest. The table structure includes a table and a ratchet mechanism. A first ratchet 100 is connected to the backrest, and a second ratchet 200 is connected to the table. The table has an unfolded position and a folded position on the back side of the backrest, and the table can move between the unfolded position and the folded position. When the table moves from top to bottom to the unfolded position, the first ratchet 100 and the second ratchet 200 are engaged with each other, and the user can manually adjust the hovering position of the table upwards. The first ratchet 100 and the second ratchet 200 restrict the downward movement of the table so that the table is hovered at the position adjusted by the user.

[0057] In this embodiment, the tabletop structure utilizes a ratchet mechanism to achieve the tabletop angle adjustment function. The working principle of the tabletop structure is as follows:

[0058] The second ratchet 200 is connected to the tabletop connecting shaft via a notch 221 on the rotating shaft 220, enabling synchronous rotation between the second ratchet 200 and the tabletop. When the tabletop is folded down, the first ratchet 100 and the second ratchet 200 remain disengaged; when opened to the lowest position, they are engaged. Specifically, the folded tabletop is first rotated to its lowest position. At this point, the first ratchet 100 and the second ratchet 200 are engaged, allowing the tabletop to move upwards in one direction. During this movement, the second ratchet 200 drives the separating plate 310 to rotate synchronously along the axis. When the tabletop moves upwards to near its folded state, the second ratchet 200 rotates, causing the clamping member 320 to move from contact with the first contact surface 311 to contact with the second contact surface 312. This means the second ratchet 200 is lifted along with the shape of the separating piece 310, disengaging the first ratchet 100 from the second ratchet 200, thus folding the tabletop and allowing it to reopen to its lowest position. The entire tabletop angle adjustment process is operable with one hand; the angle can be adjusted simply by rotating the tabletop, without any additional buttons.

[0059] This application provides an automobile seat, including a seat, a backrest, and a table structure, wherein the backrest is rotatably mounted on the seat and the table structure is connected to the back side of the backrest.

[0060] This embodiment of the car seat provides a convenient desktop for rear passengers by incorporating a table structure on the backrest. The seat provides posture support for passengers, and the backrest is rotatably mounted on the seat, allowing for adjustment of the tilt angle according to passenger needs. The table structure is connected to the backrest and can be folded away when not in use, saving space; when needed, it can be unfolded, and a ratchet mechanism keeps the table in a horizontal position for easy use.

[0061] The ratchet mechanism, table structure, and car seat provided in this application can be integrated into the connecting shaft of the table without affecting the thickness of the table. Through the cooperation of the first ratchet 100 and the second ratchet 200, there are multiple adjustment positions and a wide range of applications. The table is manually adjustable, with fast adjustment speed and one-handed operation, without the need for additional operation steps and buttons. The ratchet mechanism has few parts, resulting in low manufacturing and assembly costs. Furthermore, the angle range of the table can be adjusted by adjusting the shape of the separating plate 310, making it highly adaptable.

[0062] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0063] Furthermore, the use of terms such as "first," "second," and "a" in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0064] In this application, unless otherwise expressly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0065] Furthermore, the technical solutions of the various embodiments of this application can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this application.

Claims

1. A ratchet mechanism, characterized in that, include: The first ratchet is fixed in place; A rotatable second ratchet; A clutch assembly includes a release plate and a clamping member. The release plate is rotatably disposed on a first ratchet, and the clamping member is fixed to a second ratchet. The release plate has a first abutting surface and a second abutting surface. Rotation of the second ratchet can drive the clamping member to abut against the first abutting surface or the second abutting surface. When the clamping member abuts against the first contact surface, the first ratchet and the second ratchet are in a mutually engaged state; when the clamping member abuts against the second contact surface, the first ratchet and the second ratchet are in a disengaged state.

2. The ratchet mechanism according to claim 1, characterized in that, The end face of the first ratchet near the second ratchet is the first end face, the end face of the second ratchet near the first ratchet is the second end face, the separating plate is disposed on the first end face, and the clamping member protrudes from the second end face; The distance between the first abutting surface and the second end surface is greater than the distance between the second abutting surface and the second end surface.

3. The ratchet mechanism according to claim 2, characterized in that, The ratchet mechanism further includes a fixed shaft, with a hole on the first end face and a slot on the second end face, the fixed shaft being inserted into the hole and the slot; The separating plate is sleeved on the fixed shaft, the first abutting surface and the second abutting surface are arranged sequentially in the circumferential direction of the fixed shaft, and the clamping member is located on the outer side of the slot along the axial direction.

4. The ratchet mechanism according to claim 3, characterized in that, The separating piece is also provided with a guide arc surface, which is connected between the first abutting surface and the second abutting surface, and the clamping member can abut against the guide arc surface.

5. The ratchet mechanism according to claim 4, characterized in that, A limiting protrusion is provided on the first end face, and a limiting groove is provided on the separating piece, with the limiting protrusion disposed in the limiting groove; The limiting groove includes a first limiting surface and a second limiting surface that are spaced apart. In the circumferential direction of the fixed shaft, the distance between the first limiting surface and the second limiting surface is greater than the width of the limiting protrusion. The limiting protrusion can abut against the first limiting surface or the second limiting surface. When the limiting protrusion abuts against the first limiting surface, the clamping member abuts against the second abutting surface in sequence along the first abutting surface and the guide arc surface; When the limiting protrusion abuts against the second limiting surface, the clamping member abuts against the first abutting surface in sequence along the second abutting surface and the guide arc surface.

6. The ratchet mechanism according to claim 5, characterized in that, The clutch assembly further includes a gasket, which is disposed between the first end face and the separation plate. The gasket has a slot that engages with the limiting protrusion.

7. The ratchet mechanism according to claim 2, characterized in that, The ratchet mechanism further includes a mounting bracket and an elastic element. The first ratchet is fixed on the mounting bracket. A rotating shaft is connected to the outer wall of one end of the second ratchet along the axial direction. The rotating shaft is rotatably connected to the mounting bracket. The elastic element is sleeved on the rotating shaft, and one end of the elastic element abuts against the mounting bracket, while the other end of the elastic element abuts against the outer wall of the second ratchet.

8. The ratchet mechanism according to claim 7, characterized in that, The mounting bracket includes a first mounting plate, a second mounting plate, and a third mounting plate connected in sequence. The first mounting plate and the third mounting plate both extend axially along the rotating shaft, and the second mounting plate extends radially along the rotating shaft. The second mounting plate is provided with mounting holes, and the rotating shaft is inserted into the mounting holes.

9. A table structure disposed on the back side of a car seat backrest, characterized in that, The table structure includes a table and a ratchet mechanism according to any one of claims 1-8, wherein the first ratchet is connected to the backrest and the second ratchet is connected to the table; The tabletop has an unfolded position and a folded position on the back side of the backrest, and the tabletop can move between the unfolded position and the folded position; When the tabletop moves from top to bottom to the unfolded position, the first ratchet and the second ratchet are engaged with each other. The user can manually adjust the hovering position of the tabletop upwards, and the first ratchet and the second ratchet restrict the downward movement of the tabletop so that the tabletop is hovered at the position adjusted by the user.

10. A car seat, characterized in that, It includes a seat, a backrest, and a table structure according to claim 9, wherein the backrest is rotatably disposed on the seat and the table structure is connected to the back side of the backrest.

Images