Chassis structure with seat-back synchronous linkage device

Abstract

The present invention discloses a chassis structure with a seat-back synchronous linkage device, which includes a bottom plate fixedly arranged at the bottom of the seat and linked with the seat, a chassis arranged below the bottom plate, a tail plate assembly arranged between the bottom plate and the chassis and linked with the backrest, a seat-back synchronous linkage device arranged inside the chassis, a locking mechanism arranged inside the chassis, and a lifting mechanism arranged on the chassis; the tail plate assembly includes a tail plate and rocker plates fixedly arranged on both sides of the tail plate, and the rocker plates extend between the side surface of the chassis and the side surface of the bottom plate; the seat-back synchronous linkage device includes a first pivot shaft hinged to the side surface of the chassis and the rocker plate, a first rotating shaft located in front of the first pivot shaft and hinged to the first pivot shaft through a rotating connecting rod, a second rotating shaft located in front of the first rotating shaft and hinged to the rocker plate and the side surface of the bottom plate, and an elastic reset mechanism for resetting the bottom plate and the tail plate assembly, and the first rotating shaft is hinged to the rocker plate and the side surface of the bottom plate.

Description

Technical Field

[0001] The present invention relates to the technical field of swivel chairs, in particular to a chassis structure with a seat-back synchronous linkage device. Background Art

[0002] Swivel chairs are widely used in people's work and daily lives. They offer functions such as lifting, tilting, and rotating. They are primarily composed of legs, pneumatic rods, cylinders, a chassis structure, a seat, and a backrest. These functions are primarily achieved through the chassis structure. As people's living standards continue to improve, their demand for swivel chair comfort is also increasing. Existing swivel chairs feature a seat-back synchronization mechanism, meaning the seat and backrest operate synchronously during tilting and reclining. However, existing seat-back synchronization mechanisms are complex and cumbersome, with numerous parts, making assembly and disassembly difficult, assembly efficiency low, and processing complexity high. This leads to low production efficiency and high production costs. Furthermore, the structural design of existing seat-back synchronization mechanisms is not scientifically sound. When reclining, users must exert considerable force on the backrest to counteract their own weight, which impacts user comfort and makes reclining feel strained. Furthermore, existing elastic reset mechanisms sometimes lack sufficient elasticity, which can easily lead to weightlessness, posing a safety hazard and providing only moderate comfort. Furthermore, existing chassis structures lack elastic force adjustment, making them difficult to meet user needs.

[0003] Therefore, how to achieve a seat back synchronous linkage device with a simple structure, scientific and reasonable design, few parts, easy and convenient disassembly and assembly, effectively improving assembly efficiency, automatically adjusting the reclining elastic force according to the user's weight, easy and convenient tilting operation, and the user can adjust the backrest and seat to obtain the best posture, strong comfort, and sufficient elasticity of the elastic reset mechanism to effectively prevent weightlessness, high safety, and at the same time with elastic adjustment function is a technical problem that needs to be solved urgently in the industry. Summary of the Invention

[0004] The main purpose of the present invention is to provide a chassis structure with a seat-back synchronous linkage device, aiming to achieve a simple structure, scientific and reasonable design, few parts, easy and convenient disassembly and assembly, effectively improving assembly efficiency, and automatically adjusting the reclining elastic force according to the user's weight. The reclining operation is easy and the user can adjust the backrest and seat configuration to obtain the best posture. It is highly comfortable, and the elastic reset mechanism is full of elasticity, effectively preventing the occurrence of weightlessness, with high safety, and at the same time having a chassis structure with elastic adjustment function.

[0005] The present invention proposes a chassis structure with a seat-back synchronous linkage device, comprising a bottom plate fixedly arranged at the bottom of the seat and linked to the seat, a chassis arranged below the bottom plate, a tailboard assembly arranged between the bottom plate and the chassis and linked to the backrest, a seat-back synchronous linkage device arranged in the chassis, a locking mechanism arranged in the chassis for keeping the back-seat synchronous linkage device in an initial state or a raised state, and a lifting mechanism arranged on the chassis; the tailboard assembly comprises a tailboard, a rocker plate fixedly arranged on both sides of the tailboard, the rocker plate extending between the side surface of the chassis and the side surface of the bottom plate; the seat-back synchronous linkage device comprises a first fulcrum shaft hinged to the side surface of the chassis and the rocker plate, a first fulcrum shaft located in front of the first fulcrum shaft and connected to the first fulcrum by a rotating connecting rod The first pivot axis is hinged on the first pivot axis, the second pivot axis is located in front of the first pivot axis and hinged on the rocker and the side of the base plate, and an elastic reset mechanism plays a reset role for the base plate and the tail plate assembly. The first pivot axis is hinged on the rocker and the side of the base plate. When the backrest is reclined, the tail plate assembly is driven to rotate upward and backward, that is, the rocker is driven to rotate upward and backward around the first fulcrum axis. The rocker drives the first pivot axis and the second pivot axis to rotate upward and backward around the first fulcrum axis, thereby driving the base plate to tilt upward and backward. When the base plate is raised, the height of the front of the base plate is greater than the height of the rear of the base plate. The elastic reset mechanism includes a second fulcrum axis hinged on the side of the chassis, a second pivot axis is located in front of the second fulcrum axis and hinged The cam is adapted to move the second pivot point towards the third pivot point, and the cam is adapted to move the second pivot point towards the third pivot point, thereby enabling the cam to move relative to the second pivot point. The force-adjusting wrench has a pushing effect on the force-adjusting oblique block rubber, and the compression spring is constrained between the compression spring force-adjusting top rubber and the second fulcrum axis. The force-adjusting fixing seat extends a connecting column toward the rear that penetrates the force-adjusting oblique block rubber and the compression spring force-adjusting top rubber. The force-adjusting wrench includes a rotating seat part, a trapezoidal wrench part, and a hand-held part. The rotating seat part extends a wrench shaft toward both sides. The force-adjusting fixing seat and the force-adjusting oblique block rubber are provided with shaft grooves corresponding to the wrench shaft. The width of the wrench part gradually increases outward. When the force-adjusting wrench is bent from the initial position, the wrench part gradually pushes the force-adjusting oblique block rubber toward the second fulcrum axis, thereby pre-stressing the compression spring and increasing the initial compression amount, ultimately realizing the compression spring elastic force adjustment function.

[0006] Preferably, the lifting mechanism includes a mounting hole provided on the chassis and connected to the pneumatic rod of the swivel chair, a cylinder switch provided on the mounting hole for controlling the operation of the cylinder of the swivel chair, a locking adjustment handle extending into the chassis from the side and rotatable, and a lifting pressure plate rubber sleeved and fixed on the locking adjustment handle and capable of pressing the cylinder switch. When the locking adjustment handle is rotated, the lifting pressure plate rubber is driven to rotate so that the lifting pressure plate rubber presses on the cylinder switch to realize the lifting function; the locking adjustment handle includes a handle iron branch extending into the chassis from the side and rotatable, a handle rubber assembled and fixed with the handle iron branch, and a handle clamping rubber provided at the connection between the handle iron branch and the handle rubber for quick disassembly and assembly. The handle rubber has a clamping hole, and a circular clamping edge groove is provided at the lower opening of the clamping hole. The handle iron branch has left and right clamping grooves. The handle iron branch is inserted into the handle rubber and the left and right clamping grooves are aligned with the clamping hole. The handle clamping rubber has left and right clamping feet, and clamping blocks are provided outward at the ends of the left and right clamping feet. The left and right clamping feet are clamped into the clamping hole and inserted on both sides of the left and right clamping grooves, and the clamping blocks are clamped and fixed with the circular clamping edge groove.

[0007] Preferably, the locking mechanism includes the locking adjustment handle extending into the chassis from the side and capable of moving inward and outward, the lifting pressure plate rubber sleeved and fixed on the locking adjustment handle and moving with the inward and outward movement of the locking adjustment handle, a gear lock tooth with a plurality of gear buckles sleeved and fixed on the second rotating shaft and the third rotating shaft, a lock tongue plate provided beside the gear lock tooth and capable of being clamped into the gear buckle, a pressure plate provided on the lock tongue plate, and a locking torsion spring connecting the lock tongue plate and the lifting pressure plate rubber and playing a transmission role. A guide rail groove is provided on the pressure plate, and a guide post capable of moving along the guide rail groove is provided on the lock tongue plate. The middle part of the locking torsion spring is fixed on the chassis by a screw. One end of the locking torsion spring is connected to the lifting pressure plate rubber, and the other end of the locking torsion spring is connected to the guide post on the lock tongue plate.

[0008] Preferably, the chassis structure further includes a protective cover covering the outside of the chassis.

[0009] The present invention realizes a chassis structure with a simple structure, scientific and reasonable design, few components, easy disassembly and assembly, effectively improving the assembly efficiency, capable of automatically adjusting the backrest elastic force according to the user's weight, easy to tilt, allowing the user to configure and adjust the backrest and seat to obtain the best posture, with strong comfort, and the elastic reset mechanism having sufficient elasticity to effectively prevent weightlessness and high safety, and also having a elastic force adjustment function. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 FIG. 1 is one of the three-dimensional structure diagrams of an embodiment of the chassis structure of the present invention with a seat-back synchronous linkage device;

[0011] Figure 2 FIG. 2 is the second of the three-dimensional structure diagrams of an embodiment of the chassis structure of the present invention with a seat-back synchronous linkage device;

[0012] Figure 3 One of the partial structural decomposition diagrams of an embodiment of the chassis structure with a seat-back synchronous linkage device according to the present invention;

[0013] Figure 4 It is Figure 3 The enlarged view of part A in

[0014] Figure 5 Two of the partial structural decomposition diagrams of an embodiment of the chassis structure with a seat-back synchronous linkage device according to the present invention, where the bottom plate is not shown;

[0015] Figure 6 Three of the partial structural decomposition diagrams of an embodiment of the chassis structure with a seat-back synchronous linkage device according to the present invention;

[0016] Figure 7 Four of the partial structural decomposition diagrams of an embodiment of the chassis structure with a seat-back synchronous linkage device according to the present invention;

[0017] Figure 8 Five of the partial structural decomposition diagrams of an embodiment of the chassis structure with a seat-back synchronous linkage device according to the present invention;

[0018] Figure 9 Six of the partial structural decomposition diagrams of an embodiment of the chassis structure with a seat-back synchronous linkage device according to the present invention;

[0019] Figure 10 It is Figure 9 The enlarged view of part B in

[0020] The realization, functional features and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. Specific embodiments

[0021] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] Referring to Figures 1 to 10 , an embodiment of the chassis structure with a seat-back synchronous linkage device of the present invention is proposed, including a bottom plate 101 fixedly arranged at the bottom of the seat and linked with the seat, a chassis 102 arranged below the bottom plate 101, a tail plate assembly arranged between the bottom plate 101 and the chassis 102 and linked with the backrest, a seat-back synchronous linkage device arranged in the chassis 102, a locking mechanism arranged in the chassis 102 for keeping the back-seat synchronous linkage device in the initial state or the lifted state, a lifting mechanism arranged on the chassis 102, and the chassis structure further includes a protective cover 103 covering the outside of the chassis 102.

[0023] The tailboard assembly includes a tailboard 104 and tipping plates 105 fixedly arranged on both sides of the tailboard 104, and the tipping plates 105 extend between the side surface of the chassis 102 and the side surface of the bottom plate 101.

[0024] The seat-back synchronous linkage device includes a first pivot shaft 106 hinged to the side surface of the chassis 102 and the tipping plate 105, a first rotating shaft 108 located in front of the first pivot shaft 106 and hinged to the first pivot shaft 106 through a rotating connecting rod 107, a second rotating shaft 109 located in front of the first rotating shaft 108 and hinged to the tipping plate 105 and the side surface of the bottom plate 101, and an elastic reset mechanism for resetting the bottom plate 101 and the tailboard assembly. The first rotating shaft 108 is hinged to the side surfaces of the tipping plate 105 and the bottom plate 101. When the backrest reclines, it drives the tailboard assembly to rotate upward and backward, that is, it drives the tipping plate 105 to rotate upward and backward around the first pivot shaft 106. The tipping plate 105 drives the first rotating shaft 108 and the second rotating shaft 109 to rotate upward and backward around the first pivot shaft 106, thereby driving the bottom plate 101 to tilt upward and backward. When the bottom plate 101 rises, the rising height of the front part of the bottom plate 101 is greater than the rising height of the rear part of the bottom plate 101.

[0025] The elastic reset mechanism includes a second pivot shaft 110 hinged to the side of the chassis 102, a third rotating shaft 111 located in front of the second pivot shaft 110 and hinged to the rocker 105, a telescopic connecting shaft assembly 112 connected between the second pivot shaft 110 and the third rotating shaft 111, and a compression spring 113 sleeved outside the connecting shaft assembly 112 and constrained between the second pivot shaft 110 and the third rotating shaft 111. When the rocker 105 rotates upward and backward, the third rotating shaft 111 rotates around the second pivot shaft 110, so that the third rotating shaft 111 gradually approaches the second pivot shaft 110, thereby forcing the compression spring 113 to contract and generate elastic force. The seat-back synchronous linkage device of the present invention can automatically adjust the magnitude of the backward tilt elastic force according to the user's weight. During the backward tilt process, when the user's weight is larger, the acting force of the tail plate assembly and the bottom plate 101 on the compression spring 113 is larger. And the more the compression spring 113 is compressed, the greater the rebound force is, and the greater the reaction force of the compression spring 113 on the tail plate assembly and the bottom plate 101 is, so that the magnitude of the backward tilt elastic force can be automatically adjusted according to the user's weight. The elastic reset mechanism adopted in the present invention is the compression spring 113. The compression spring 113 is a helical spring that bears compressive force, can bear strong pressure, and has a high elastic coefficient. When tilting, even when the user tilts backward to the end, that is, the maximum tilt angle, the force applied by the user to the compression spring 113 is the largest. The elastic force of the compression spring 113 of the elastic reset mechanism of the present invention can easily cope with the force applied by the user to the backrest and the bottom plate 101, and there will be no weightlessness situation, and the comfort of the user during tilting is high. The structure of the seat-back synchronous linkage device of the present invention is simple, the design is scientific and reasonable, the number of parts is small, it can automatically adjust the magnitude of the backward tilt elastic force according to the user's weight, the tilting operation is easy, the user can configure and adjust the backrest and the seat to obtain the best posture, the comfort is strong, and the elastic reset mechanism has sufficient elastic force, effectively preventing the occurrence of weightlessness, and the safety is high.

[0026] The seat back synchronous linkage device also includes a force adjustment mechanism that can adjust the elastic force of the compression spring 113. The force adjustment mechanism includes a force adjustment fixing seat 123 provided on the third rotating shaft 111, a force adjustment oblique block rubber 124 with an inclined surface close to the rear end of the force adjustment fixing seat 123, a compression spring force adjustment top rubber 125 close to the inclined surface, and a force adjustment wrench provided between the force adjustment fixing seat 123 and the force adjustment oblique block rubber 124 and having a pushing effect on the force adjustment oblique block rubber 124. The compression spring 113 is constrained between the compression spring force adjustment top rubber 125 and the second fulcrum shaft 110. The force adjustment fixing seat 123 extends rearward to penetrate the force adjustment oblique block rubber 124 and the compression spring force adjustment top rubber 125. The force adjustment wrench includes a rotating seat portion 126, a The trapezoidal wrench part 127, the hand-held part 128, and the rotating seat part 126 extend the wrench shaft 129 on both sides. The force adjustment fixing seat 123 and the force adjustment bevel rubber 124 are provided with a shaft groove 138 corresponding to the wrench shaft 129. The width of the wrench part 127 gradually increases outward. When the force adjustment wrench is bent from the initial position, the wrench part 127 gradually pushes the force adjustment bevel rubber 124 toward the second fulcrum axis 110, thereby pre-stressing the compression spring 113 and increasing the initial compression amount. In this way, the elastic force of the compression spring 113 can be increased. In this way, the elastic force of the compression spring 113 can be adjusted by adjusting the initial pre-stress length of the compression spring 113, thereby realizing the compression spring elastic force adjustment function.

[0027] The lifting mechanism includes a mounting hole 130 provided on the chassis 102 and connected to the pneumatic rod of the swivel chair, a cylinder switch provided on the mounting hole 130 for controlling the operation of the cylinder of the swivel chair, a locking and adjusting handle extending from the side into the chassis 102 and being rotatable, and a lifting and lowering pressure plate rubber 114 which is fixed on the locking and adjusting handle and can press the cylinder switch. When the locking and adjusting handle is rotated, the lifting and lowering pressure plate rubber 114 is driven to rotate so that the lifting and lowering pressure plate rubber 114 is pressed against the cylinder switch to realize the lifting function. The locking and adjusting handle includes a handle iron rod 131 that extends from the side into the chassis 102 and is rotatable, a handle glue 132 assembled and fixed with the handle iron rod 131, and a handle clamping glue 133 provided at the connection between the handle iron rod 131 and the handle glue 132 for quick disassembly and assembly. The handle glue 132 is provided with a clamping hole 134, and the lower end opening of the clamping hole 134 is provided with an annular clamping edge groove. The handle iron rod 131 is provided with left and right clamping grooves 135. The handle iron rod 131 is inserted into the handle glue 132 and the left and right clamping grooves 135 correspond to the clamping hole 134. The handle clamping glue 133 is provided with left and right clamping feet 136, and a clamping block 137 is provided outward at the end of the left and right clamping feet 136. The left and right clamping feet 136 are clamped into the clamping hole 134 and interspersed on both sides of the left and right clamping grooves 135, and the clamping block 137 is clamped and fixed with the annular clamping edge groove.

[0028] During assembly, simply insert the handle iron rod 131 into the handle rubber 132 and align the left and right card slots 135 with the card holes 134, then snap in the handle clamping rubber 133. The disassembly and assembly are simple and convenient, forming a quick disassembly and assembly structure for the locking and adjusting handle, effectively improving the assembly efficiency.

[0029] The locking mechanism includes the locking and adjusting handle that extends into the chassis 102 from the side and can be pushed and pulled in and out, the lifting pressure plate rubber 114 sleeved and fixed on the locking and adjusting handle and moving with the in-and-out push and pull movement of the locking and adjusting handle, the gear locking teeth 115 with several gear bayonets 116 sleeved and fixed on the second rotating shaft 109 and the third rotating shaft 111, the locking tongue plate 117 arranged beside the gear locking teeth 115 and capable of engaging into the gear bayonet 116, the pressure plate 118 arranged on the locking tongue plate 117, the locking torsion spring 119 connected between the locking tongue plate 117 and the lifting pressure plate rubber 114 and playing a transmission role. There is a guide rail groove 120 on the pressure plate 118, and a guide post 121 that can move along the guide rail groove 120 on the locking tongue plate 117. The middle part of the locking torsion spring 119 is fixed on the chassis 102 by a screw 122. One end of the locking torsion spring 119 is connected to the lifting pressure plate rubber 114, and the other end of the locking torsion spring 119 is connected to the guide post 121 on the locking tongue plate 117.

[0030] When the gear locking teeth 115 move with the movement of the second rotating shaft 109 and the third rotating shaft 111, the locking tongue plate 117 corresponds to a certain gear bayonet 116 of the gear locking teeth 115. When it is necessary to lock the tilting angle, push the locking and adjusting handle. The locking and adjusting handle will drive the lifting pressure plate rubber 114 to move, thus driving the locking torsion spring 119 to move. The movement of the locking torsion spring 119 drives the locking tongue plate 117 to move along the guide rail groove 120, and finally makes the locking tongue plate 117 move and engage into the gear bayonet 116, thereby locking the movement of the second rotating shaft 109 and the third rotating shaft 111. When it is necessary to unlock, simply pull out the locking and adjusting handle in the reverse direction. The structure of this locking mechanism is simple and reasonable. With a simple structure, the backrest synchronous linkage device can be maintained in the initial state or the lifted state, and the locking in the lifted state can be achieved, and the operation is simple and convenient.

[0031] Through the seat-back synchronous linkage device, the user can perform the tilting operation simply and comfortably relative to their own body weight. When adjusted to a suitable tilting angle, the tilting angle can be locked through the locking mechanism. The user can configure and adjust the backrest and seat through the seat-back synchronous linkage device to obtain the best posture, with strong comfort.

[0032] The present invention realizes a chassis structure with a simple structure, scientific and reasonable design, few components, easy disassembly and assembly, effectively improving the assembly efficiency, capable of automatically adjusting the reclining elastic force according to the user's weight, with easy reclining operation, allowing the user to configure and adjust the backrest and seat to obtain the best posture, having strong comfort, and the elastic reset mechanism having sufficient elasticity to effectively prevent the situation of weightlessness, with high safety, and simultaneously having a function of adjusting the elastic force.

[0033] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structural transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

Claims

1. Chassis structure with seat-back synchronous linkage device, characterized in that: It includes a bottom plate fixed to the bottom of the seat and linked to the seat, a chassis provided below the bottom plate, a tailboard assembly provided between the bottom plate and the chassis and linked to the backrest, a seat-back synchronization linkage device provided in the chassis, a locking mechanism provided in the chassis for maintaining the seat-back synchronization linkage device in an initial state or a raised state, and a lifting mechanism provided on the chassis; The tailboard assembly includes a tailboard and a rocker plate fixed on both sides of the tailboard, wherein the rocker plate extends between the side of the chassis and the side of the bottom plate; The seat back synchronous linkage device includes a first fulcrum axis hinged on the side surface of the chassis and the rocker plate, a first rotating axis located in front of the first fulcrum axis and hinged to the first fulcrum axis through a rotating connecting rod, a second rotating axis located in front of the first rotating axis and hinged on the rocker plate and the side surface of the bottom plate, and an elastic reset mechanism that plays a reset role for the bottom plate and the tail plate assembly. The first rotating axis is hinged on the rocker plate and the side surface of the bottom plate. When the backrest is reclined, the tail plate assembly is driven to rotate upward and backward, that is, the rocker plate is driven to rotate upward and backward around the first fulcrum axis. The rocker plate drives the first rotating axis and the second rotating axis to rotate upward and backward around the first fulcrum axis, thereby driving the bottom plate to tilt upward and backward. When the bottom plate is raised, the height of the front of the bottom plate is greater than the height of the rear of the bottom plate. The elastic return mechanism includes a second fulcrum axis hinged on the side of the chassis, a third rotation axis located in front of the second fulcrum axis and hinged on the rocker, a retractable connecting axis assembly connected between the second fulcrum axis and the third rotation axis, and a compression spring sleeved outside the connecting axis assembly and constrained between the second fulcrum axis and the third rotation axis. When the rocker rotates upward and backward, the third rotation axis rotates about the second fulcrum axis, gradually approaching the second fulcrum axis, thereby forcing the compression spring to contract and generate elastic force. The seat back synchronous linkage device also includes a force adjustment mechanism that can adjust the elastic force of the compression spring. The force adjustment mechanism includes a force adjustment fixing seat provided on the third rotating shaft, a force adjustment oblique block rubber with an inclined surface close to the rear end of the force adjustment fixing seat, a pressure spring force adjustment top rubber close to the inclined surface, a force adjustment wrench provided between the force adjustment fixing seat and the force adjustment oblique block rubber and having a pushing effect on the force adjustment oblique block rubber, the compression spring is constrained between the pressure spring force adjustment top rubber and the second fulcrum axis, the force adjustment fixing seat extends rearward and penetrates the force adjustment oblique block rubber, the pressure spring force adjustment The connecting column of the top rubber, the force wrench includes a rotating seat part, a trapezoidal wrench part, and a hand-held part. The rotating seat part extends a wrench shaft on both sides. The force adjustment fixing seat and the force adjustment oblique block rubber are provided with a shaft groove corresponding to the wrench shaft. The width of the wrench part gradually increases outward. When the force adjustment wrench is bent from the initial position, the wrench part gradually pushes the force adjustment oblique block rubber toward the second fulcrum axis, thereby pre-compressing the compression spring and increasing the initial compression amount to finally realize the compression spring elastic force adjustment function; The locking mechanism includes a locking adjustment handle extending from the side into the chassis and capable of being pushed and pulled inward and outward, a lifting and lowering pressure plate rubber mounted on the locking adjustment handle and moving with the inward and outward pushing and pulling of the locking adjustment handle, a gear lock tooth with a plurality of gear bayonet slots mounted on the second rotating shaft and the third rotating shaft, a lock tongue plate provided next to the gear lock tooth and capable of being engaged in the gear bayonet slot, a pressure plate provided on the lock tongue plate, a locking torsion spring connected between the lock tongue plate and the lifting and lowering pressure plate rubber and playing a transmission role, a guide rail groove is provided on the pressure plate, and a guide column movable along the guide rail groove is provided on the lock tongue plate, the middle part of the locking torsion spring is fixed to the chassis by a screw, one end of the locking torsion spring is connected to the lifting and lowering pressure plate rubber, and the other end of the locking torsion spring is connected to the guide column on the lock tongue plate.

2. The chassis structure with seat back synchronous linkage device according to claim 1, characterized in that: The lifting mechanism includes a mounting hole provided on the chassis and connected to the pneumatic rod of the swivel chair, a cylinder switch provided on the mounting hole and capable of controlling the operation of the cylinder of the swivel chair, a rotatable locking and adjusting handle extending from the side into the chassis, and a lifting and lowering pressure plate rubber sleeved and fixed on the locking and adjusting handle and capable of pressing the cylinder switch. When the locking and adjusting handle is rotated, the lifting and lowering pressure plate rubber is driven to rotate so that the lifting and lowering pressure plate rubber presses the cylinder switch to realize the lifting function. The locking and adjusting handle includes a handle iron rod extending from the side into the chassis and being rotatable, a handle glue assembled and fixed with the handle iron rod, and a handle clamping glue provided at the connection between the handle iron rod and the handle glue and realizing quick disassembly and assembly. The handle glue is provided with a clamping hole, and an annular clamping edge groove is provided at the opening of the lower end of the clamping hole. The handle iron rod is provided with left and right clamping grooves. The handle iron rod is inserted into the handle glue so that the left and right clamping grooves correspond to the clamping holes. The handle clamping glue is provided with left and right clamping feet, and clamping blocks are provided outward at the ends of the left and right clamping feet. The left and right clamping feet are clamped into the clamping hole and interspersed on both sides of the left and right clamping grooves, and the clamping blocks are clamped and fixed with the annular clamping edge grooves. When the gear lock tooth moves with the movement of the second rotating shaft and the third rotating shaft, the lock tongue plate corresponds to a gear slot of the gear lock tooth. When the tilt angle needs to be locked, the locking adjustment handle is pushed. The locking adjustment handle will drive the lifting pressure plate rubber to move, thereby driving the locking torsion spring to move. The movement of the locking torsion spring drives the lock tongue plate to move along the guide rail groove, and finally the lock tongue plate moves and engages in the gear slot, thereby locking the movement of the second rotating shaft and the third rotating shaft. When the lock needs to be unlocked, just pull the locking adjustment handle in the opposite direction.

3. The chassis structure with seat back synchronous linkage device according to claim 1 or 2, characterized in that: The chassis structure also includes a protective cover arranged outside the chassis.

Images