A chassis mechanism of a seat and a seat

Abstract

The invention discloses a chassis mechanism of a chair and a chair, comprising a base, a bracket and a seesaw; a first pin is passed through between the front end of the bracket and the front end of the base, so that the bracket rotates around the base with the first pin as a fulcrum; a second pin is passed through between the front end of the seesaw and the rear end of the base, so that the seesaw rotates around the base with the second pin as a rotating shaft; a linkage structure is provided between the rear end of the bracket and the rear end of the seesaw, the linkage structure comprises a third pin passed through the bracket and the seesaw, and a track groove for guiding the movement trajectory of the seesaw; the track groove is arranged on both sides of one of the seesaw or the bracket, and the third pin is passed through the track groove; the bracket has a forward tilting state and a backward tilting state, when the bracket tilts forward, the third pin slides along the track groove and acts on the seesaw, so that the rear end of the seesaw is synchronously tilted upward; when the bracket tilts backward, the third pin slides along the track groove and acts on the seesaw, so that the rear end of the seesaw is synchronously tilted downward; the chair realizes the synchronous tilting of the seat and the backrest.

Description

Technical Field

[0001] The invention relates to the field of seating, and in particular to a chassis mechanism of a seat and the seat. Background Art

[0002] Children generally have two states of learning, reading and doing homework. These two states have different requirements for the angles of the chair backrest and seat cushion. When reading, the backrest tilts backward (the backrest is 100°-120° from the horizontal), while maintaining a more suitable human body opening angle, and the seat cushion is also tilted upward (the seat cushion is 3°-10° from the horizontal plane). When doing homework, the upper body of the human body leans forward (80°-95° ​​from the horizontal angle), while maintaining a more suitable human body opening angle, and the seat cushion angle also changes (the seat cushion is negative 10°-positive 5° from the horizontal angle), at this time the backrest is forward and fits the back of the human body. Both states require the backrest to be close to the waist, especially in the homework state, the backrest is forward and fits the waist, so that when the human body is doing homework in an incorrect posture such as arching the waist or hunching back, the backrest will give the waist a force to ensure the correct sitting posture of the human body, so as to effectively prevent myopia and hunchback; therefore, it is necessary to enable the seat and back of the chair to be able to tilt synchronously so that the backrest can always support the human waist.

[0003] The chassis mechanism of the currently known reclining backrest chair is composed of an upper tray, a lower tray, a support shaft and spring device components. After the upper tray is fixed to the back of the swivel chair, the swivel chair can tilt appropriately around the support shaft seat and can automatically return to make the user feel comfortable. However, the design of the chair chassis only takes into account the state of the human body tilting backward, and does not take into account the state of the human body leaning forward; when the human body leans backward, the backrest will be in line with the human body and tilt backward; when the human body leans forward, there is no contact with the backrest, and the backrest will not fit the human body forward.

[0004] Therefore, it is necessary to design a chassis with synchronous seat and backrest tilting. When a person sits on the seat and leans back or forward, the backrest is driven to tilt by the tilt of the seat itself; so that the backrest can always fit the waist of the human body to provide support, reduce the burden on the human body, and be more ergonomic. Such a chassis generally includes a base fixed to the bottom of the seat, a bracket for fixing the seat, and a seesaw for connecting the backrest; when the person leans back or forward on the seat, the bracket rotates around the base, and the seesaw can rotate synchronously with the rotation of the bracket so that the backrest always supports the human body. In such a chassis, the linkage structure of the seesaw and the bracket is the focus of the design, which is the key to solving the above problems. Summary of the invention

[0005] The present invention overcomes the deficiencies existing in the above-mentioned prior art. Firstly, it provides a chassis mechanism of a seat, wherein the bracket of the chassis is connected to the chassis via a first pin shaft, and the rocker is connected to the chassis via a second pin shaft; the bracket and the rocker are connected via a third pin shaft, and a track groove is provided at the connection between the rocker and the chassis; the bracket rotates with the first pin shaft as a fulcrum, and the bracket has a forward tilting and backward tilting state; when the bracket is in the process of tilting forward and backward around the chassis, the third pin shaft slides along the track groove and acts on the rocker, so that the rear end of the rocker can tilt up or down synchronously.

[0006] Then, a chair with a synchronously tilting seat back is provided. When a person uses the chair to lean forward or backward, the seat tilts forward and backward relative to the chair leg support assembly. Through the above-mentioned chassis mechanism, the chair back can tilt forward and backward around the chair leg support assembly at the same time to fit the waist of the person and provide support.

[0007] The technical solution of the present invention is achieved in this way:

[0008] A chassis mechanism of a seat, comprising a base, a bracket and a seesaw; a first pin is passed through between the front end of the bracket and the front end of the base, so that the bracket rotates around the base with the first pin as a fulcrum; a second pin is passed through between the front end of the seesaw and the rear end of the base, so that the seesaw rotates around the base with the second pin as a rotating axis; a linkage structure is provided between the rear end of the bracket and the rear end of the seesaw, and the linkage structure comprises a third pin passed through the bracket and the seesaw, and a track groove for guiding the movement trajectory of the seesaw; the track groove is provided on both sides of one of the seesaw or the bracket, And the third pin shaft is passed through the track groove; the front end part of the bracket located at the first pin shaft forms a first lever, and the rear end part of the bracket located at the first pin shaft forms a second lever; in the initial position, the bracket is in a horizontal state; the bracket has a forward tilting and a backward tilting state, when the bracket tilts forward, the first lever tilts downward, the second lever tilts upward, the third pin shaft slides along the track groove and acts on the seesaw, so that the rear end of the seesaw tilts upward synchronously; when the bracket tilts backward, the first lever tilts upward, the second lever tilts downward, the third pin shaft slides along the track groove and acts on the seesaw, so that the rear end of the seesaw tilts downward synchronously.

[0009] The chassis mechanism of the seat of the present invention rotates around the rotating shaft as a fulcrum through the bracket, so that the second lever tilts up or down; at the same time, the third pin shaft slides along the track groove to act on the rocker, so that the rear end of the rocker is synchronously tilted up or backward; thereby, the rocker can be rotated at the same time through the rotation of the bracket, and the seat and back can be tilted synchronously.

[0010] Preferably, the second lever is longer than the first lever; when the bracket tilts forward or backward, the movement stroke of the front end of the first lever is smaller than the movement stroke of the rear end of the second lever in the height direction, so that when the bracket rotates, the height range of the front end of the bracket tilting up and down is small, which does not affect the comfort of human use.

[0011] Preferably, when the bracket tilts forward, the height of the third pin is higher than the height of the first pin; when the bracket tilts backward, the height of the third pin is lower than the height of the first pin.

[0012] Preferably, the track grooves are symmetrically arranged on both sides of the rear end of the seesaw, and from top to bottom, the track grooves are inclined toward the direction close to the base, so that when the third pin slides along the track of the track groove, it can act on the rear end of the seesaw to follow the bracket to tilt up and down, and the direction remains consistent.

[0013] Preferably, the base includes a bottom plate and support plates extending upward in the vertical direction along the left and right sides of the bottom plate; the bracket includes a support plate, and front connecting plates that cooperate with the first pin shaft extend downward on both sides of the front end of the support plate; the support plate is located between the two front connecting plates, and the two ends of the first pin shaft respectively pass through the support plate and the front connecting plate in sequence.

[0014] Preferably, the rocker includes side plates spaced apart on the left and right and a mounting plate connected to the bottoms of the two side plates; the support plate is located between the two side plates, and both ends of the second pin shaft pass through the support plate and the side plates in sequence.

[0015] Preferably, the track groove is arranged at the rear end of the side panel; rear connecting plates cooperating with the third pin shaft also extend downward on both sides of the rear end of the support plate, and the two side panels are located between the rear connecting plates on the left and right sides; the two ends of the third pin shaft respectively pass through the track groove and the rear connecting plate in sequence.

[0016] Preferably, a spring for the bracket to rotate and reset is provided on the first pin shaft, and the spring is a torsion spring, which is sleeved on the first pin shaft, and two torsion arms of the torsion spring are respectively against the bracket and the base. The reset spring makes the bracket have a good damping feeling during the rotation around the base, and can reset the bracket.

[0017] A chair includes a leg support assembly, a seat, a backrest and a chassis mechanism of the chair, wherein the seat is connected to the leg support assembly, the backrest is connected to a rocker, and the seat is connected to a bracket; the bracket is connected below the seat, and the bracket is located at the rear end of the seat; the first pin is located at the center below the seat; when the bracket tilts forward, the seat tilts forward relative to the leg support assembly, and the backrest tilts backward synchronously; when the bracket tilts backward, the seat tilts backward relative to the leg support assembly, and the backrest tilts forward synchronously. When using the chair, the seat can tilt forward or backward relative to the leg support assembly according to changes in human body posture and center; and through the above-mentioned chassis mechanism, the backrest can tilt synchronously during the seat tilting process; the backrest can always fit the human waist to provide support, making the chair more comfortable to use.

[0018] Preferably, a connecting rod is connected between the chair back and the rocker, and the rocker rotates around the base to act on the chair back to tilt it.

[0019] The design starting point, concept and beneficial effects of the present invention using the above technical solution are:

[0020] 1. Through the joint action of the first, second and third pins, the seesaw can rotate synchronously while the bracket rotates around the base; the bracket tilts forward, and the rear end of the seesaw tilts up; the bracket tilts backward, and the rear end of the seesaw tilts down; so that the seat and back of the chair using the chassis can maintain synchronous tilting, so that the backrest always fits the back of the human body during the use of the seat; it conforms to ergonomics; especially when children use it, the backrest fits the waist forward, so that when the child writes homework in an incorrect posture such as arching the waist or hunching over, the backrest will give a force to the waist to ensure the correct sitting posture of the human body, thereby effectively preventing myopia and hunchback.

[0021] 2. The bracket is connected under the base, and the bracket is located at the rear end of the base; so that the first pin is located at the center position under the seat, that is, when the seat is in use, the first pin is located near the center of gravity of the human body; then when the center of gravity of the human body on the seat changes, the seat and back are tilted synchronously; according to the change of the center of gravity of the human body, corresponding adjustments are made, so that the use effect of the seat is better and the experience is comfortable.

[0022] 3. Furthermore, the first pin is located near the center of gravity of the human body, so that when the bracket rotates with the first pin as the fulcrum, the gravity of the human body is applied near the fulcrum, and the lever arm is small; the bracket will not tilt easily, avoiding the shaking feeling when the seat rotates; thus, the rotation of the seat is smoother and more stable to use.

[0023] 4. The first pin is located at the front end of the bracket, that is, the length of the first lever is much smaller than the length of the second lever; that is, when the bracket rotates with the first pin as the fulcrum, the up and down tilting height range of the front end of the first lever is much smaller than the up and down tilting height range of the rear end of the second lever, so that the up and down tilting height of the front end of the seat will not be too large, avoiding affecting the comfort of human body when using it;

[0024] 5. The synchronous reclining structure of the seat and back of the chassis mainly relies on the weight of the human body to make the seat and back tilt; and when returning, it also mainly relies on the gravity of the human body to return; so that people of light or heavy weight can easily lean forward or backward; it is suitable for a wider range of people and has a larger scope of use. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the three-dimensional structure of the chassis in the embodiment of the present invention;

[0026] Figure 2It is a schematic diagram of the three-dimensional structure of the chassis at another angle in the embodiment of the present invention;

[0027] Figure 3 An exploded view of a chassis in an embodiment of the present invention;

[0028] Figure 4 It is a schematic diagram of the three-dimensional structure of the bracket in the embodiment of the present invention without rotation;

[0029] Figure 5 It is a schematic diagram of the three-dimensional structure of the bracket when it is tilted backward in the embodiment of the present invention;

[0030] Figure 6 It is a schematic diagram of the three-dimensional structure of the bracket when it is tilted forward in an embodiment of the present invention;

[0031] Figure 7 A schematic diagram showing the movement of the bracket rotating with the first rotating shaft as a fulcrum in an embodiment of the present invention;

[0032] Figure 8 is a schematic diagram of the three-dimensional structure of the bracket in an embodiment of the present invention;

[0033] Fig. 9 It is a schematic diagram of the three-dimensional structure of the base in an embodiment of the present invention;

[0034] Fig.10 It is a schematic diagram of the three-dimensional structure of the seesaw in an embodiment of the present invention;

[0035] Fig.11 It is a schematic diagram of the three-dimensional structure of a seat in an embodiment of the present invention;

[0036] Fig.12 This is a schematic diagram of a human body using a seat reclining in an embodiment of the present invention;

[0037] Fig.13 It is a schematic diagram of a human body using a seat leaning forward in an embodiment of the present invention.

[0038] The reference numerals of the figures are as follows: base 1; bracket 2; rocker 3; first pin 4; first lever A; second lever B; front end point c; rear end point d; support plate 5; front connecting plate 6; bottom plate 7; support plate 8; convex cap 9; second pin 10; mounting plate 11; side plate 12; linkage structure 13; third pin 14a; track groove 14b; rear connecting plate 15; spring 16; mounting seat 17; locking mechanism 18; lock hole 19; latch 20; socket 21; chair leg 22; seat 23; backrest 24; connecting rod 25; mounting hole 26. DETAILED DESCRIPTION

[0039] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0040] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0041] In the description of the present invention, the term "at least one" refers to one or more than one, unless otherwise clearly defined. The terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0042] The reference positions of various parts involved in this embodiment, such as front and back, are described under normal use conditions after a user sits down.

[0043] The specific implementation of the present invention is as follows:

[0044] like Figure 1-10 As shown, the present invention provides a chassis structure of a seat, including a base 1, a bracket 2 and a rocker 3.

[0045] like Figure 2-10 As shown, the seesaw 3 and the base 1 are both located below the bracket 2, the base 1 is located inside the bracket 2, and a first pin 4 is provided between the front end of the bracket 2 and the front end of the base 1, so that the bracket 2 can rotate forward and backward around the base 1 with the first pin 4 as a fulcrum, specifically: Figure 8 As shown, the bracket 2 includes a support plate 5, and front connecting plates 6 are respectively extended downward from both sides of the front end of the support plate 5; Fig. 9 As shown, the base 1 includes a bottom plate 7 and support plates 8 extending upward in the vertical direction along the left and right sides of the bottom plate 7; during installation, the base 1 is placed in the bracket 2 so that the two support plates 8 are located between the two front connecting plates 6; the first pin shaft 4 is a whole long axis, and the first pin shaft 4 is inserted from one side of the bracket 2, and the first pin shaft 4 passes through the front connecting plate 6 and the support plate 8 in turn and then passes out from the other side of the bracket 2; that is, the bracket 2 can be rotated around the base through the first pin shaft 4; and convex caps 9 are respectively provided at both ends of the first pin shaft 4 so that the first pin shaft 4 will not separate from the bracket 2.

[0046] like Figure 4-7 As shown, the front end of the bracket 2 located at the first pin 4 forms a first lever A, and the rear end of the bracket 2 located at the first pin 4 forms a second lever B; in the initial position, the bracket 2 is in a horizontal state; the bracket 2 has a forward tilt and a backward tilt state, as shown in FIG. Figure 7 As shown, when the bracket 2 tilts forward, the first lever A tilts downward, the second lever B tilts upward, the front end point c of the bracket drops, and the rear end point d rises; when the bracket 2 tilts backward, the first lever A tilts upward, the second lever B tilts downward, the front end point c of the bracket drops, and the rear end point d rises.

[0047] like Figure 2-7 As shown, the seesaw 3 is located at the rear end of the base 1 and a second pin 10 is passed between the front end of the seesaw 3 and the rear end of the base 1, so that the seesaw 3 can also rotate forward and backward around the base 1 with the second pin 10 as the rotation axis; specifically: Fig.10 As shown, the rocker 3 includes a mounting plate 11, and side plates 12 extend upward along the left and right sides of the mounting plate 11 respectively; the support plates 8 on both sides of the base 1 are located between the two side plates 12, and the second pin shaft 10 is also a whole long axis; the second pin shaft 10 is inserted from one side of the rocker 3, so that it passes through the side plate 12 and the support plate 8 in turn and then passes out from the other side of the rocker 3; that is, the rocker 3 can rotate around the base 1 through the second pin shaft 10; and convex caps 9 are also provided at both ends of the second pin shaft 10, so that the second pin shaft 10 will not separate from the rocker 3.

[0048] In addition, a linkage structure 13 is provided between the rear end of the bracket 2 and the rear end of the seesaw 3, and the linkage structure 13 includes a third pin shaft 14a passing through the bracket 2 and the seesaw 3, and a track groove 14b for guiding the movement trajectory of the seesaw 3; the third pin shaft 14a is passed through the track groove 14b, and the third pin shaft 14a slides along the track groove 14b to act on the seesaw 3, so that when the bracket 2 rotates around the base 1, the seesaw 3 will rotate around the base 1 synchronously. Specifically, rear connecting plates 15 cooperating with the third pin 14a are extended downward on both sides of the rear end of the support plate 5; the two side plates 12 of the rocker 3 are located between the two rear connecting plates 15; the track groove 14b is opened at the corresponding position of the side plate 12, and from top to bottom, the track groove 14b is inclined in the direction close to the base 1; the third pin 14a penetrates the bracket 2 and the rocker 3 from one side, and the third pin 14a passes through the rear connecting plate 14 and the track groove 14b in turn and then passes out from the other side; and convex caps 9 are provided at both ends of the third pin 14a so that the third pin 14a will not be separated from the rocker 3; when the second lever B at the rear end of the bracket 2 is tilted up or down, the third pin 14a will follow the rise or fall, that is, when the bracket 2 is tilted forward, the height of the third pin 14a will be higher than the height of the first pin 4; when the bracket 2 is tilted backward, the height of the third pin 14a will be lower than the height of the first pin 4.

[0049] like Figure 4-7As shown, when the bracket 2 rotates forward and backward around the base 1 with the first pin 4 as a fulcrum, the third pin 14a follows the rotation of the bracket 2 to rise or fall, so that the third pin 14a slides along the track groove 14b to act on the rocker 3 so that the rear end of the rocker 3 rotates synchronously around the base 1; specifically: Figure 3 As shown, the chassis is in the initial position at this time, and the support plate 5 is in a horizontal position; when the bracket 2 tilts backward, the bracket 2 rotates backward around the base 1, as shown in FIG. Figure 4 As shown, the third pin 14a will rotate backward with the bracket 2, the third pin 14a slides along the track groove 14b and the height of the third pin 14a decreases; and the third pin 14a abuts against the track groove 14b, so that the seesaw 3 will rotate backward around the base 1, that is, the rear end of the seesaw 3 tilts downward; when the third pin 14a abuts against the rear end of the track groove 14b, the seesaw 3 cannot continue to rotate backward, and this is the maximum angle of the seesaw 3 and the bracket 2 to rotate backward. When the bracket 2 tilts forward, the bracket 2 rotates forward around the base 1, as shown in FIG. Figure 5 As shown, the third pin 14a rotates forward with the bracket 2, the third pin 14a slides along the track groove 14b and the third pin 14a rises in height, and the third pin 14a then abuts against the track groove 14b, so that the rocker 3 will rotate forward around the base 1, that is, the rear end of the rocker 3 tilts upward; when the third pin 14a abuts against the rear end of the track groove 14b, the rocker 3 cannot continue to rotate forward, and this is the maximum angle at which the rocker 3 and the bracket 2 can rotate forward.

[0050] like Figure 1 , 3 As shown, a spring 16 for the bracket 2 to rotate and reset around the base 1 is also provided on the first pin shaft 4, and the spring 16 is a torsion spring; the spring 16 is sleeved on the first pin shaft 4; a mounting seat 17 is also provided in the base 1, and the mounting seat 17 is connected between the two support plates 8, and the two torsion arms of the spring 16 are respectively abutted against the lower end of the mounting seat 17 and the lower end of the support plate 5; when the bracket 2 rotates around the base 1, the spring 16 can provide elastic force for the rotation and reset of the bracket 2; and the spring 16 makes the bracket 2 have a good damping feeling during the rotation process, effectively eliminating the shaking, abnormal noise and other problems caused by the assembly gap. In addition, a locking mechanism 18 for limiting the rotation of the bracket 2 is provided between the bracket 2 and the base 1, and the locking mechanism 18 includes a lock hole 19 and a latch 20; the lock hole 19 is provided on the support plate 8, and a plug hole 21 is provided at a corresponding position of the front connecting plate 6 on the same side; when locked, the latch 20 passes through the plug hole 21 and is inserted into the lock hole 19, thereby limiting the rotation of the bracket 2 around the base 1; so that the human body can stay at any tilt angle of the bracket 2.

[0051] like Figure 11-13As shown, the present invention then provides a chair, including a chair leg support assembly 22, a seat 23, a seat back 24 and the chassis mechanism of the chair, a mounting hole 26 is provided on the base 1, and the base 1 is connected and fixed to the chair leg support assembly 22 through the mounting hole 26; the support plate 5 on the bracket 2 is fixed to the seat 23 by screws, and the bracket 2 is located at the rear end of the base 1; the first pin shaft 4 is located at the center position under the seat; a connecting rod 25 is provided at the rear of the seat back 24, and the connecting rod 25 is connected and fixed to the mounting plate 11 of the rocker 3.

[0052] Then, when the human body is using the chair to recline, the seat 23 and the backrest 24 can rotate synchronously; specifically, as follows: Fig.11 As shown, when the human body tilts backward, the seat 23 tilts backward, and the backrest 24 tilts backward synchronously to fit the human waist; Fig.12 As shown, when the human body tilts forward, the seat 23 tilts forward slightly, and the backrest 24 tilts forward synchronously to fit the human waist. When the chair is in use, the seat 23 and the backrest 24 keep tilting synchronously, and the backrest can always fit the human body, provide a supporting effect, improve the comfort of the chair, and better conform to ergonomics.

[0053] The first pin 1 is located near the center of gravity of the human body, so that the seat 23 can be rotated and adjusted according to the change of the center of gravity of the human body, and the experience is comfortable and the effect is better; in addition, if Figure 4-7 As shown, the first pin 4 is located at the front end of the bracket 2, so that the length of the second lever B is much longer than the length of the first lever A; that is, when the bracket 2 rotates with the first pin 4 as the fulcrum, the up and down tilting height range of the front end point c of the first lever A is much smaller than the up and down tilting height range of the rear end point d of the second lever B, so that the up and down tilting height of the front end of the seat 23 will not be too large, so as to avoid affecting the comfort of human body when using it; and the first pin 4 is located near the center of gravity of the human body, so that when the bracket 2 rotates with the first pin 4 as the fulcrum, the gravity of the human body is applied near the fulcrum, and the lever arm is small; so that the bracket 2 will not tilt easily, avoiding the shaking feeling when the seat rotates; thereby making the rotation of the seat smoother and more stable to use.

Claims

1. A chassis structure of a seat, characterized in that: The cam is an angularly-spaced structure formed on a pair of camshafts, the cam being arranged on a pair of camshafts, and the cam being arranged on a pair of camshafts, the cam being arranged on a pair of camshafts, and the cam being arranged on a pair of camshafts, the cam being arranged on a pair of camshafts, and the cam being arranged on a pair of camshafts. The rod tilts upward, and the third pin slides along the track groove and acts on the seesaw, so that the rear end of the seesaw is synchronously tilted upward; when the bracket tilts backward, the first lever tilts upward, the second lever tilts downward, and the third pin slides along the track groove and acts on the seesaw, so that the rear end of the seesaw is synchronously tilted downward; rear connecting plates that cooperate with the third pin are respectively extended downward on both sides of the rear end of the bracket; the two side plates of the seesaw are located between the two rear connecting plates; the track groove is opened at the corresponding positions of the side plates, and from top to bottom, the track groove is inclined in the direction close to the base; the third pin penetrates the bracket and the seesaw from one side, and the third pin passes through the rear connecting plate and the track groove in turn and then passes out from the other side; and convex caps are provided at both ends of the third pin; when the second lever at the rear end of the bracket tilts upward or downward, the third pin will follow the rise or fall, that is, when the bracket tilts forward, the height of the third pin will be higher than the height of the first pin; when the bracket tilts backward, the height of the third pin will be lower than the height of the first pin.

2. The seat chassis structure according to claim 1, characterized in that: The second lever is longer than the first lever; when the bracket tilts forward or backward, the movement stroke of the front end of the first lever along the height direction is smaller than the movement stroke of the rear end of the second lever.

3. The seat chassis structure according to claim 1, characterized in that: The track grooves are symmetrically arranged on both sides of the rear end of the seesaw, and from top to bottom, the track grooves are inclined toward the direction close to the base.

4. The seat chassis structure according to claim 1, characterized in that: The base includes a bottom plate and support plates extending upward in the vertical direction along the left and right sides of the bottom plate; the bracket includes a support plate, and front connecting plates that cooperate with the first pin shaft extend downward on both sides of the front end of the support plate; the support plate is located between the two front connecting plates, and the two ends of the first pin shaft respectively pass through the support plate and the front connecting plate in sequence.

5. The seat chassis structure according to claim 4, characterized in that: The rocker plate comprises side plates spaced apart on the left and right and a mounting plate connected to the bottoms of the two side plates; the support plate is located between the two side plates, and the two ends of the second pin shaft respectively pass through the support plate and the side plates in sequence.

6. The seat chassis structure according to claim 5, characterized in that: The track groove is arranged at the rear end of the side plate; rear connecting plates cooperating with the third pin shaft extend downward on both sides of the rear end of the support plate, and the two side plates are located between the rear connecting plates on the left and right sides; the two ends of the third pin shaft respectively pass through the track groove and the rear connecting plate in sequence.

7. The seat chassis structure according to claim 1, characterized in that: A spring for rotating and resetting the bracket is arranged on the first pin shaft, and the spring is a torsion spring. The torsion spring is sleeved on the first pin shaft, and two torsion arms of the torsion spring are respectively against the bracket and the base.

8. A seat, characterized in that: It includes a chair leg support assembly, a seat, a backrest and a chassis mechanism of a seat as described in any one of claims 1 to 7, the base is connected to the chair leg support assembly, the backrest is connected to the rocker, and the seat is connected to the bracket; the bracket is connected under the base, and the bracket is located at the rear end of the base; the first pin shaft is located at the center position under the seat; when the bracket tilts forward, the seat tilts forward relative to the chair leg support assembly, and the backrest tilts backward synchronously; when the bracket tilts backward, the seat tilts backward relative to the chair leg support assembly, and the backrest tilts forward synchronously.

9. The seat according to claim 8, characterized in that: A connecting rod is connected between the chair back and the rocker, and the rocker rotates around the base to act on the chair back to tilt it up and down.

Images