Dual-system seat
By designing a parallel four-bar structure for the dual-system seat, the backrest and seat can switch between adaptive lumbar support and self-weight tilting states, solving the problem that existing seats cannot recline and improving the practicality and user experience of the seat.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- ANJI SUEE SMART HOME CO LTD
- Filing Date
- 2025-05-06
- Publication Date
- 2026-07-30
AI Technical Summary
The existing chairs cannot rotate their backrests to a large angle suitable for reclining during use, which fails to meet the user's need to recline and rest, thus lacking practicality.
Design a dual-system seat that uses a backrest, long support rod, rear support, and backrest support to form a parallel four-bar structure. The long support rod drives the short support rod to rotate, which in turn moves the seat up and down, thus achieving the switching between adaptive lumbar support and self-weight reclining states of the backrest.
It enables a smooth switch between adaptive lumbar support and self-weight tilting modes, meeting the user's needs for backrest adjustment and tilting, and improving the practicality and user experience of the seat.
Smart Images
Figure CN2025092787_30072026_PF_FP_ABST
Abstract
Description
Dual-system seats Technical Field
[0001] This invention relates to the field of seating technology, and more specifically to dual-system seating. Background Technology
[0002] Nowadays, people often need to sit for long periods of time for work or study. If posture is incorrect during this time, it can easily lead to many problems such as nearsightedness, scoliosis, and lumbar muscle strain, especially for teenagers whose bodies are still developing. To help users maintain good posture, a push-back chair has appeared on the market. When a user sits in this chair, the backrest automatically moves forward, providing stable support for the user's back and helping to correct their posture.
[0003] For example, the applicant's prior patent provides a seat bracket and seat (publication number: CN219661278U), which consists of a base, mounting rod, support rod, armrest, and connecting rod forming a four-bar linkage. When the four-bar linkage is activated, the connecting block on the mounting rod rotates forward / backward, and the backrest mounting seat on the armrest moves forward / backward with the armrest. When the connecting block rotates forward, it drives the seat connecting frame to descend and move forward; when the connecting block rotates backward, it drives the seat connecting frame to rise and move backward. Since the backrest mounting seat moves forward / backward with the armrest, the backrest mounted on the backrest mounting seat moves forward and backward accordingly, so that the backrest can maintain the correct support angle for the human body.
[0004] However, in the pursuit of excellence and in the direction of structural optimization, the following shortcomings were found: During use, the backrest can only move back and forth in a vertical position; if the user wants to lie down to rest after working or studying, the backrest cannot rotate back at a large angle to a suitable angle for the user to lie down, making it impossible for the user to lie down and rest. The chair cannot meet the user's deeper needs and is not very practical. Technical issues
[0005] In view of the above-mentioned defects or deficiencies in the prior art, it is desirable to provide a dual-system seat, which forms a parallel four-bar structure by hinged backrest, long support rod, rear bracket and backrest support to each other, and the long support rod drives the short support rod to rotate, which in turn moves the seat up and down; so that the seat not only has an adaptive lumbar support state in which the backrest responds to the seat sinking and moves forward to follow the backrest, but also has a self-weight tilting state in which the backrest is tilted backward and the seat is raised accordingly, which can simultaneously meet the user's backrest adjustment needs and tilting adjustment needs, and has good practicality. Technical solutions
[0006] The effects of this invention are achieved as follows:
[0007] This application provides a dual-system seat, including:
[0008] The backrest is configured to support the user's back.
[0009] The chair seat is configured to support the user when seated.
[0010] The base is a split structure, consisting of an upper and lower seat support and a backrest support. The front ends of the seat support and the backrest support are hinged to each other, allowing the backrest support to rotate up and down relative to the seat support.
[0011] The rotating support rod is located on the left and right sides of the front end of the seat support. The rotating support rod includes a short support rod and a long support rod that are inclined to each other and always remain relatively fixed. The part where the lower ends of the short support rod and the long support rod meet is the rotating part. The rotating support rod is hinged to the seat support through the rotating part, so that the entire rotating support rod can rotate synchronously around the rotating part. The upper end of the long support rod is hinged to the backrest, and the upper end of the short support rod is hinged to the seat. The seat can slide up and down relative to the seat support, and drive the short support rod to rotate back and forth around the rotating part.
[0012] The lower end of the rear support is hinged to the rear end of the backrest support, and the upper end of the rear support is hinged to the backrest.
[0013] The dual-system seat has switchable initial state, adaptive lumbar support state, and self-weight reclining state. In the initial state, the seat is unpressed and in a high position, and the backrest is unsupported and remains upright. In the initial state, when the seat is pressed down, the dual-system seat switches to the adaptive lumbar support state. The short and long support rods are driven forward synchronously by the seat, and the rear support responds to the long support rod's synchronous forward swing, thereby causing the backrest, which is hinged to the long support rod and the upper side of the rear support, to be moved forward and pushed out. In the initial state, when the backrest is supported, the dual-system seat switches to the self-weight reclining state. The backrest support rotates downward relative to the backrest support, and the backrest responds to the backrest support's synchronous downward rotation. The long support rod and the rear support rotate backward synchronously, allowing the upper backrest to recline backward. The short and long support rods swing backward synchronously, causing the seat to move upward.
[0014] Furthermore, in the adaptive lumbar support mode, the backrest moves 0-15cm horizontally; in the self-weight reclining mode, the backrest tilts 0-30°. This ensures that in the adaptive lumbar support mode, the backrest has a sufficiently long forward and backward sliding range to accommodate the seat depth of users of various body types; and in the self-weight reclining mode, the backrest has a sufficiently large tilt angle to ensure that users can rest in a comfortable reclining position, making it highly practical.
[0015] Furthermore, a locking device is provided between the seat support and the backrest support, which has a switchable locked and unlocked state. When the dual-system seat is switched to the adaptive lumbar support state, the locking device is locked, and the seat support and backrest support are relatively fixed. When the dual-system seat is switched to the self-weight-bearing recline state, the locking device is unlocked, and the backrest support can rotate relative to the seat support again. By switching between the locked and unlocked states using the locking device, the dual-system seat can be switched between the initial state, the adaptive lumbar support state, and the self-weight-bearing recline state, making the adjustment operation relatively simple. Moreover, the adaptive lumbar support state and the self-weight-bearing recline state do not interfere with each other, resulting in good stability for the dual-system seat.
[0016] Furthermore, the front end of the seat support is provided with a first connecting part, and the front end of the backrest support is provided with a second connecting part. The first connecting part is hinged to the second connecting part. The first connecting part has a first limiting hole with a left-right opening along its upper edge, and the second connecting part has a second limiting hole with a left-right opening along its upper edge. The locking device includes a locking pin, which is slidably connected to the first limiting hole and the second limiting hole. In the locked state, the first limiting hole is connected to the second limiting hole, and the locking pin slides to simultaneously engage with both the first and second limiting holes, preventing the second connecting part from rotating relative to the first connecting part, thus fixing the seat support and the backrest support relatively. In the unlocked state, the locking pin slides to avoid the first or second limiting hole, allowing the backrest support to rotate again relative to the seat support. By sliding and adjusting the locking pin to simultaneously engage or avoid the first and second limiting holes, the locking device can switch between locked and unlocked states. This not only makes the adjustment operation simple but also simplifies the overall structure and makes it easy to set up.
[0017] Furthermore, the front end of the backrest support is provided with two symmetrical second connecting parts, which are hinged to the left and right sides of the first connecting part. The rotating parts on both sides are respectively hinged to the two second connecting parts. The locking device also includes a pressing part, which is located on the side of the rotating part near the second connecting part. In the adaptive lumbar support state, the rotating part rotates forward, and the pressing part rotates accordingly and pushes the locking pin inward, causing the locking pin to slide inward until it simultaneously engages with the first and second limiting holes. The locking device enters the locked state, and the seat support and backrest support are relatively fixed. In the self-weight reclining state, the rotating part rotates backward, and the pressing part rotates accordingly and avoids the locking pin, causing the locking pin to slide outward until it disengages from the first limiting hole. The locking device enters the unlocked state, allowing the backrest support to rotate downward relative to the seat support again. This ensures that when the dual-system seat switches from the initial state to the adaptive lumbar support state or the self-weight reclining state, the locking device can automatically switch between the locked and unlocked states with the rotation of the rotating part, effectively improving the ease of operation for switching the dual-system seat states.
[0018] Furthermore, a first elastic element is provided within the second limiting hole. This first elastic element acts on the locking pin, causing the locking pin to always tend to move away from the first connecting part. When the dual-system seat switches directly from the initial state to the self-weighted reclining state, the locking pin can automatically pop outward with the help of the elastic force of the first elastic element and disengage from the first limiting hole. This allows the locking device to automatically switch to the unlocked state, further improving the ease of operation for switching the dual-system seat states.
[0019] Furthermore, the end face of the extrusion part near the locking pin and / or the end face of the locking pin near the extrusion part are inclined, so that when the rotating part drives the extrusion part to make a circular motion and pushes the locking pin, the locking pin can slide towards the first connecting part along the inclined direction of the aforementioned end faces. By inclining the end faces of the extrusion part and / or the locking pin that are close to each other, the structure is simple and can realize the conversion of the circular rotation of the extrusion part into the sliding of the locking pin in the horizontal direction.
[0020] Furthermore, a second elastic element is provided between the seat support and the backrest support. The two ends of the second elastic element act on the seat support and the backrest support respectively, ensuring that the backrest support always tends to rotate towards the seat support. When the dual-system seat switches from a self-weight-bearing tilt state back to its initial state, the backrest support automatically rotates upwards under the elastic force of the second elastic element, thereby causing the upper backrest to return to its initial state, thus improving the ease of switching between the dual-system seat states.
[0021] Furthermore, the backrest support includes a sliding support extending rearward and a sliding member slidably connected to the sliding support in a front-to-back direction. The bottom end of the rear support is hinged to the sliding member. In the self-weight-bearing reclining state, the sliding member is subjected to pressure from the rear support and slides forward. The bottom end of the rear support is driven forward by the sliding member, causing the top end of the rear support to rotate rearward and causing the backrest, hinged to the top end of the rear support, to tilt further backward. This allows the backrest to tilt backward at a greater angle, enabling the user to recline comfortably on the seat. Furthermore, as the seat rises, the backrest rotates at a larger angle, preventing back rubbing and enhancing the user experience.
[0022] Furthermore, a gear adjustment component is fixedly connected to the sliding support. A gear adjustment mechanism is provided between the sliding component and the gear adjustment component. The gear adjustment mechanism includes a locking head and several gear slots. The locking head is located in one of the sliding component and the gear adjustment component, and the several gear slots are located in the other of the sliding component and the gear adjustment component. When the sliding component slides back and forth relative to the gear adjustment component, the locking head engages with the several gear slots in sequence. This allows the sliding component to be fixed at any position on the sliding support, thereby enabling the backrest to be adjusted and fixed at the tilt angle using the gear adjustment mechanism, making it more convenient to use.
[0023] Furthermore, the locking head is movably connected to the gear adjustment component, and the sliding component is correspondingly provided with several gear slots. The gear adjustment mechanism has a switchable fixed state and a sliding state. In the fixed state, the locking head slides outward to engage with the gear slot, making the sliding component and the gear adjustment component relatively fixed. In the sliding state, the locking head slides inward to retract into the gear adjustment component and avoid the gear slot, allowing the sliding component to slide relative to the gear adjustment component again. By using the movement of the locking head to engage or avoid the gear slot, the movement or fixation between the sliding component and the sliding support is realized, which facilitates operation and makes the gear adjustment operation relatively simple.
[0024] Furthermore, the slider has a plate-like structure with a first sliding support groove extending in the front-to-back direction. A gear adjustment component is slidably connected to the slider, and a limiting part protrudes from the gear adjustment component. The limiting part passes through the first sliding support groove and connects to the sliding support component, so that the slider is clamped between the sliding support component and the gear adjustment component, and the slider slides back and forth relative to the limiting part through the first sliding support groove. This not only increases the connection strength between the slider and the sliding support component, but also makes the sliding process of the slider smoother and more stable.
[0025] Furthermore, the lower end of the chair seat is provided with two symmetrical chassis connecting parts, which fit against the left and right sides of the chair seat support. The chassis connecting parts and the chair seat support are connected by a guide mechanism, which includes a guide groove and a guide pin that slide against each other. The guide groove is located in one of the chassis connecting parts and the chair seat support, and the guide pin is located in the other. By sliding the guide pin in the guide groove, the chair seat slides up and down relative to the chair seat support and rotates back and forth in conjunction with the short support rod. The structure is simple and makes the transmission process between the chair seat and the short support rod more stable and smooth.
[0026] Furthermore, the guide groove includes a lumbar support guide and a tilt guide, both of which are inclined from front to back and from low to high. The lumbar support guide has a greater inclination relative to the horizontal plane than the tilt guide. By inclining the guide groove, the horizontal position of the chair seat changes as it slides up and down. The greater inclination of the lumbar support guide results in less horizontal movement of the chair seat in the adaptive lumbar support state, preventing interference with seat depth adjustment. In the self-weight tilting state, the chair seat moves a longer distance horizontally to accommodate the changing position of the buttocks when the back is reclined, providing a more comfortable support experience.
[0027] Furthermore, the short support rod is hinged to the front end of the seat, and the chassis connection is located at the rear end of the seat with a guide groove formed in the chassis connection. The seat can be positioned directly above the base, making the location more reasonable; by placing the guide groove in the chassis connection, it is easier to process and will not affect the merging of the seat support and backrest support.
[0028] Furthermore, a third elastic element is provided between the seat and the seat support. In the initial state, the third elastic element does not apply any elastic force to the seat and seat support. In the adaptive lumbar support state, the third elastic element applies a pushing force to the seat and seat support, causing the seat to tend to move away from the seat support. In the self-weight reclining state, the third elastic element applies a pulling force to the seat and seat support, causing the seat to tend to move closer to the seat support. This allows the seat to automatically reset, and by driving the seat to rotate the support rod, backrest support, rear bracket, and backrest, the dual-system seat returns to its initial state without requiring manual reset by the user, further improving the convenience of switching between dual-system seat states.
[0029] Furthermore, the third elastic element is a controllable gas spring. The seat and the third elastic element are connected by a wired control mechanism. The wired control mechanism includes an adjustment switch and a pull cord connecting the adjustment switch and the third elastic element. The adjustment switch is configured to adjust the pull cord to pull or release the pin of the third elastic element, thereby allowing the third elastic element to be fixed at any extension length. Simply pressing the adjustment switch can adjust the extension or fixation of the third elastic element, and also cause the backrest to move or be fixed, making the adjustment operation very simple.
[0030] The dual-system seat provided in this application constructs a parallel four-bar structure by hingedly connecting the backrest, long support rod, rear bracket, and backrest support. The long support rod drives the short support rod to rotate, which in turn moves the seat up and down. This allows the dual-system seat to not only have an adaptive lumbar support state where the backrest responds to the seat's downward movement and slides forward to support the back, but also a self-weight-bearing reclining state where the backrest tilts backward and the seat rises accordingly. It can simultaneously meet the user's needs for both backrest adjustment and tilt adjustment, making it highly practical. The dual-system seat's state switching operation is not only simple, but the transition between each state is also very natural and smooth, providing a very comfortable user experience.
[0031] Furthermore, by designing the chassis as a split structure, the seat support and backrest support are locked or movable via a locking device. When the locking device is locked, the long support rod and rear bracket can only swing back and forth, thereby causing the backrest to move forward and backward. When the locking device is unlocked, the backrest support can rotate downward relative to the seat support, thereby causing the upper backrest to rotate downward as well. Thus, by switching between the locked and unlocked states using the locking device, the dual-system seat can be switched between the initial state, the adaptive lumbar support state, and the self-weighted reclining state, making the adjustment operation relatively simple. In the adaptive lumbar support state, the backrest cannot be tilted, thus not affecting the backrest's backrest adjustment. Similarly, in the self-weighted reclining state, the backrest cannot be moved forward, thus not affecting the backrest's tilt adjustment. In other words, the adaptive lumbar support state and the self-weighted reclining state do not interfere with each other, resulting in good stability for the dual-system seat. Attached Figure Description
[0032] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:
[0033] Figure 1 is a three-dimensional structural diagram of the dual-system seat provided in an embodiment of this application;
[0034] Figure 2 is a schematic diagram of the bottom structure of the dual-system seat provided in an embodiment of this application;
[0035] Figure 3 is a side view of the dual-system seat in its initial state according to an embodiment of this application;
[0036] Figure 4 is a side view of the dual-system seat in the adaptive lumbar support state provided in the embodiment of this application;
[0037] Figure 5 is a side view of the dual-system seat in the self-weight tilting state provided in the embodiment of this application;
[0038] Figure 6 is a schematic diagram of the change process of the dual-system seat from the initial state to the adaptive lumbar support state provided in the embodiment of this application;
[0039] Figure 7 is a schematic diagram of the change process of the dual-system seat from the initial state to the self-weighted tilting state provided in the embodiment of this application;
[0040] Figure 8 is a cross-sectional structural diagram of the dual-system seat provided in an embodiment of this application;
[0041] Figure 9 is a schematic diagram of the connection structure between the chair seat and the chassis provided in an embodiment of this application;
[0042] Figure 10 is a schematic diagram of the connection structure between the seat support and the backrest support provided in an embodiment of this application;
[0043] Figure 11 is a cross-sectional structural diagram of the chassis in the unlocked state provided in an embodiment of this application;
[0044] Figure 12 is a cross-sectional view of the chassis in the locked state provided in an embodiment of this application;
[0045] Figure 13 is a three-dimensional structural diagram of the chassis and rear support in the locked state provided in the embodiment of this application;
[0046] Figure 14 is a three-dimensional structural diagram of the chassis and rear support in the unlocked state provided in the embodiment of this application;
[0047] Figure 15 is a schematic diagram of the connection structure between the chassis and the rear support provided in an embodiment of this application;
[0048] Figure 16 is a schematic diagram of the internal structure of the gear adjustment mechanism provided in the embodiment of this application;
[0049] Figure 17 is a schematic diagram of the connection structure between the gear adjustment component and the sliding component in a fixed state according to an embodiment of this application;
[0050] Figure 18 is a schematic diagram of the connection structure between the gear adjustment component and the sliding component in the sliding state provided in the embodiment of this application.
[0051] The reference numerals in the attached figures are as follows: 1 - backrest, 110 - armrest, 120 - armrest, 2 - seat, 210 - chassis connection, 211 - guide groove, 211a - lumbar support guide, 211b - tilt guide, 220 - third elastic element, 230 - adjustment switch, 3 - seat support, 301 - guide pin, 310 - first connecting part, 311 - first limiting hole, 320 - transmission element, 4 - backrest support, 401 - locking pin, 402 - first elastic element, 403 - second elastic element, 410 - third elastic element. Two connecting parts, 411-second limiting hole, 420-sliding support part, 430-sliding component, 431-gear groove, 432-first sliding support groove, 433-second sliding support groove, 440-gear adjustment component, 441-clip head, 442-limiting part, 443-accommodating cavity, 444-torsion spring, 445-push-pull component, 446-fourth elastic component, 5-rotating support rod, 510-short support rod, 520-long support rod, 530-rotating part, 531-pressing part, 6-rear bracket. Embodiments of the present invention
[0052] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.
[0053] Please refer to Figures 1-18. An embodiment of this application provides a dual-system seat, including:
[0054] Backrest 1, configured to support the user's back;
[0055] Seat 2, configured to support the user when seated;
[0056] The base is a split structure, including a seat support 3 and a backrest support 4 that are spliced together. The front ends of the seat support 3 and the backrest support 4 are hinged to each other, so that the backrest support 4 can rotate up and down relative to the seat support 3.
[0057] Rotating support rod 5 is located on the left and right sides of the front end of the seat support part 3. The rotating support rod 5 includes a short support rod 510 and a long support rod 520 that are inclined to each other and always remain relatively fixed. The lower ends of the short support rod 510 and the long support rod 520 meet at the rotating part 530. The rotating support rod 5 is hinged to the seat support part 3 through the rotating part 530, so that the entire rotating support rod 5 can rotate synchronously around the rotating part 530. The upper end of the long support rod 520 is hinged to the backrest 1, and the upper end of the short support rod 510 is hinged to the seat 2. The seat 2 can slide up and down relative to the seat support part 3, and drive the short support rod 510 to rotate back and forth around the rotating part 530.
[0058] The rear support 6 has its lower end hinged to the rear end of the backrest support 4 and its upper end hinged to the backrest 1.
[0059] The dual-system seat has a switchable initial state, an adaptive lumbar support state, and a self-weight reclining state. In the initial state, the seat 2 is unpressed and in a high position, and the backrest 1 is unsupported and remains upright. When the seat 2 is pressed downwards in the initial state, the dual-system seat switches to the adaptive lumbar support state. The short support rod 510 and the long support rod 520 are driven forward synchronously by the seat 2, and the rear support 6 responds by swinging forward synchronously with the long support rod 520, thus allowing the hinged rear support to... The backrest 1 on the upper side of the support rod 520 and the rear support 6 is moved forward and pushed out. In the initial state, when the backrest 1 is subjected to a reclining force, the dual-system seat switches to a self-weight reclining state. The backrest support part 4 rotates downward relative to the backrest support part 3. The backrest 1 responds to the backrest support part 4 and rotates downward synchronously. The long support rod 4 and the rear support 6 rotate backward synchronously, so that the upper backrest 1 can recline backward. The short support rod 510 and the long support rod 520 swing backward synchronously, and drive the seat 2 to move upward.
[0060] In this embodiment, the backrest 1, the long support rod 520, the rear bracket 6, and the backrest support part 4 are hinged together to form a parallel four-bar structure. The long support rod 520 drives the short support rod 510 to rotate and moves the seat 2 up and down. This allows the dual-system seat to not only have an adaptive lumbar support state where the backrest 1 responds to the seat 2 sinking and moving forward to follow the backrest, but also a self-weight tilting state where the backrest 1 is tilted backward and the seat 2 is raised accordingly. This can simultaneously meet the user's backrest adjustment needs and tilt adjustment needs, making it highly practical. Furthermore, in the adaptive lumbar support mode, when the user wants to recline, they only need to lean back forcefully. The backrest 1 tilts backward, and the seat 2 rises accordingly. Once in the initial position, the backrest 1 tilts further backward with the pressure of the user's back, and the dual-system seat automatically enters the self-weight-bearing reclining mode. At this time, the back does not need to lean back forcefully, and the backrest 1 can automatically tilt backward to adapt to the user's weight and lift the seat 2. Similarly, in the self-weight-bearing reclining mode, when the user wants to sit upright, they only need to press down on the seat 2 with their buttocks forcefully. The backrest 1 rotates forward until it reaches the initial position. Then, with the pressure of the user's buttocks, the seat 2 presses down further, and the dual-system seat automatically enters the adaptive lumbar support mode. At this time, the buttocks do not need to press down forcefully, and the seat 2 can automatically sink to adapt to the user's weight and move the backrest 1 forward to follow the back. Therefore, the dual-system seat's state switching operation is not only simple, but the transition between each state is also very natural and smooth, providing a very comfortable user experience.
[0061] Preferably, the left and right ends of the backrest 1 extend forward to form armrest portions 110, and the top end of the long support rod 520 is hinged to the armrest portion 110. The armrest portion 110 has a sleeve-like structure with a vertical cutout, and each of the left and right armrest portions 110 is fitted with an armrest 120. This allows the armrest 120 to move together with the backrest 1 in either the adaptive lumbar support state or the self-weight reclining state, ensuring that the armrest 120 always remains in a position supporting the user's hands without the need for tedious adjustments, resulting in a more comfortable and convenient user experience. Furthermore, the armrest 120 is slidably connected to the armrest portion 110 via an armrest height mechanism, allowing the armrest 120 to slide up and down to adjust its height, improving practicality. This armrest height mechanism is a common mechanism in existing chairs and will not be described in detail in this patent.
[0062] Please refer to Figures 6-7. In some embodiments of this application, in the adaptive lumbar support state, the horizontal movement distance of the backrest 1 is 0-15cm; in the self-weight reclining state, the reclining angle of the backrest 1 is 0-30°. This ensures that in the adaptive lumbar support state, the backrest 1 has a sufficiently long forward and backward sliding range to accommodate the seat depth of users of various body types; and in the self-weight reclining state, the backrest 1 has a sufficiently large tilt angle to ensure that the user can rest in a comfortable reclining posture, thus demonstrating good practicality.
[0063] Please refer to Figures 9-12. In some embodiments of this application, a locking device is provided between the seat support 3 and the backrest support 4. The locking device has a switchable locked state and an unlocked state. When the dual-system seat is switched to the adaptive lumbar support state, the locking device is in the locked state, and the seat support 3 and the backrest support 4 are relatively fixed. When the dual-system seat is switched to the self-weight reclining state, the locking device is in the unlocked state, and the backrest support 4 can rotate relative to the seat support 3 again.
[0064] In this embodiment, the seat support 3 and the backrest support 4 are locked or movable via a locking device. When the locking device is locked, the long support rod 520 and the rear bracket 6 can only swing back and forth, thereby causing the backrest 1 to move forward and backward. When the locking device is unlocked, the backrest support 4 can rotate downward relative to the seat support 3, thereby causing the upper backrest 1 to rotate downward as well. Thus, by switching between the locked and unlocked states using the locking device, the dual-system seat can be switched between the initial state, the adaptive lumbar support state, and the self-weight tilting state, making the adjustment operation relatively simple. Furthermore, in the adaptive lumbar support state, the backrest 1 cannot tilt, thus not affecting the backrest 1's backrest adjustment. Similarly, in the self-weight tilting state, the backrest 1 cannot move forward, thus not affecting the backrest 1's tilt adjustment. That is, the adaptive lumbar support state and the self-weight tilting state do not interfere with each other, resulting in good stability of the dual-system seat.
[0065] Of course, in other embodiments of this application, a locking device may not be provided between the seat support 3 and the backrest support 4. The user can switch between the initial state, the adaptive lumbar support state and the self-weight reclining state by applying pressure to one of the seat 2 and the backrest 1. No further locking operation is required, and the adjustment operation is simpler.
[0066] Please refer to Figures 9-12. In some embodiments of this application, the front end of the seat support 3 is provided with a first connecting part 310, and the front end of the backrest support 4 is provided with a second connecting part 410. The first connecting part 310 is hinged to the second connecting part 410. The first connecting part 310 has a first limiting hole 311 hollowed out along its upper edge in a left-right direction, and the second connecting part 410 has a second limiting hole 411 hollowed out along its upper edge in a left-right direction. The locking device includes a locking pin 401, which is slidably connected to the first limiting hole 310. 11 and second limiting hole 411; In the locked state, the first limiting hole 311 connects to the second limiting hole 411, and the locking pin 401 slides to simultaneously engage with the first limiting hole 311 and the second limiting hole 411, so that the second connecting part 410 cannot rotate relative to the first connecting part 310, and the seat support part 3 and the backrest support part 4 are relatively fixed; In the unlocked state, the locking pin 401 slides to avoid the first limiting hole 311 or the second limiting hole 411, and the backrest support part 4 can rotate again relative to the seat support part 3.
[0067] In this embodiment, the locking device can be switched between locked and unlocked states by simultaneously engaging or disengaging the first limiting hole 311 and the second limiting hole 411 through the sliding adjustment locking pin 401. This not only makes the adjustment operation simple, but also makes the overall structure relatively simple and easy to set up.
[0068] Both the backrest support 4 and the seat support 3 are semi-open box-shaped structures. In the locked state, the seat support 3 and the backrest support 4 close together to form a complete base, making the base structure more compact. The backrest support 4 can rotate at a large angle relative to the seat support 3.
[0069] Please refer to Figures 9-12. In some embodiments of this application, the front end of the backrest support 4 is provided with two symmetrical second connecting parts 410. The two second connecting parts 410 are hinged to the left and right sides of the first connecting part 310, and the rotating parts 530 on both sides are respectively hinged to the two second connecting parts 410. The locking device also includes a pressing part 531, which is disposed on the side of the rotating part 530 near the second connecting part 410. In the adaptive lumbar support state, the rotating part 530 rotates forward, and the pressing part 531 rotates accordingly. Push the locking pin 401 inward, causing it to slide inward until it simultaneously engages with the first limiting hole 311 and the second limiting hole 411. The locking device enters the locked state, and the seat support 3 and the backrest support 4 are relatively fixed. In the self-loaded tilting state, the rotating part 530 rotates backward, and the pressing part 531 rotates accordingly and avoids the locking pin 401, causing the locking pin 401 to slide outward until it disengages from the first limiting hole 311. The locking device enters the unlocked state, allowing the backrest support 4 to rotate downward relative to the seat support 3 again.
[0070] In this embodiment, by providing a pressing part 531 on the rotating part 530, the pressing part 531 rotates in a circular motion with the rotation of the rotating part 530 and pushes or avoids the locking pin 401. This allows the locking device to automatically switch between locked and unlocked states as the rotating part 530 rotates, eliminating the need for manual adjustment by the user and effectively improving the ease of switching between states of the dual-system seat. Furthermore, the front end of the backrest support part 4 is provided with two symmetrical second connecting parts 410. The two rotating parts 530 are respectively connected to the second connecting parts 410 on both sides, so that the seat support part 3 and the backrest support part 4 are limited by two sets of locking pins 401. As the rotating support rods 5 on both sides of the dual-system seat rotate, the two sets of locking pins 401 are simultaneously driven to slide, making the locking or unlocking operation between the seat support part 3 and the backrest support part 4 smoother.
[0071] Please refer to Figures 11-12. In some embodiments of this application, a first elastic element 402 is provided in the second limiting hole 411. The first elastic element 402 acts on the locking pin 401 and makes the locking pin 401 always tend to move away from the first connecting part 310.
[0072] In this embodiment, when the dual-system seat switches directly from the initial state to the self-weight reclining state, when the rotating part 530 rotates to the pressing part 531 to avoid the locking pin 401, the locking pin 401 can automatically pop outward with the help of the elastic force of the first elastic member 402 and disengage from the first limiting hole 311, thereby enabling the locking device to automatically switch to the unlocked state, so that the dual-system seat can automatically enter the adaptive lumbar support state, further improving the ease of operation of the dual-system seat state switching.
[0073] Preferably, the first elastic element 402 is a spring, the locking pin 401 has a T-shaped structure, the wider side of the locking pin 401 is close to the pressing part 531, the spring is sleeved on the slender side of the locking pin 401 and presses the locking pin 401 outward, the structure is simple and easy to set.
[0074] Please refer to Figures 9-10. In some embodiments of this application, the end face of the pressing part 531 near the locking pin 401 and / or the end face of the locking pin 401 near the pressing part 531 are inclined, so that when the rotating part 530 drives the pressing part 531 to make a circular motion and pushes the locking pin 401, the locking pin 401 can slide towards the first connecting part 310 along the inclined direction of the end face.
[0075] In this embodiment, by tilting the end faces of the pressing part 531 and / or the locking pin 401 that are close to each other, the structure is simple and can realize the conversion of the circumferential rotation of the pressing part 531 into the sliding of the locking pin 401 in the horizontal direction.
[0076] Preferably, the end face of the extrusion part 531 near the locking pin 401 and the end face of the locking pin 401 near the extrusion part 531 are both inclined, so that the transmission between the two is more stable and smooth.
[0077] Please refer to Figure 10. In some embodiments of this application, a second elastic member 403 is provided between the seat support 3 and the backrest support 4. The two ends of the second elastic member 403 act on the seat support 3 and the backrest support 4 respectively, so that the backrest support 4 always has a tendency to rotate toward the seat support 3.
[0078] In this embodiment, by providing a second elastic element 403 between the seat support 3 and the backrest support 4, when the dual-system seat switches from the self-weight tilting state back to the initial state, the backrest support 4 will automatically rotate upward under the elastic force of the second elastic element 403, thereby driving the upper backrest 1 to rotate forward back to the vertical state, thus resetting to the initial state. The user does not need to manually rotate the backrest 1 to reset, thereby improving the convenience of the dual-system seat state switching operation.
[0079] Please refer to Figures 13-14. In some embodiments of this application, the backrest support 4 includes a sliding support 420 extending rearward from the rear end and a sliding member 430 slidably connected to the sliding support 420 along the front-rear direction. The bottom end of the rear support 6 is hinged to the sliding member 430. In the self-loaded tilting state, the sliding member 430 is subjected to pressure from the rear support 6 and slides forward. The bottom end of the rear support 6 is driven by the sliding member 430 and slides forward, causing the top end of the rear support 6 to rotate backward and causing the backrest 1 hinged to the top end of the rear support 6 to tilt further backward.
[0080] In this embodiment, if the backrest 1 is tilted by rotating only the backrest support 4, the angle that the backrest support 4 can rotate is small, and the angle that the backrest 1 can rotate is also small, which makes it impossible for the user to recline on the seat and fails to meet the needs. Furthermore, since the seat 2 moves upward synchronously with the backrest 1, if the backrest 1 cannot rotate to a larger angle during the tilting process, the backrest 1 will rub against the user's back as the seat 2 rises, resulting in a poor user experience. Therefore, by hinged to the bottom of the rear support 6 to the sliding member 430 that can slide back and forth, in the self-weight reclining state, in addition to the backrest 1 being tilted back by the rotation of the backrest support 4, the rear support 6 rotates backward as the sliding member 430 moves forward, causing the upper backrest 1 to tilt back further. This allows the backrest 1 to tilt back at a greater angle, which not only allows the user to lie back on the seat in a more comfortable posture, but also, as the seat 2 is raised, the backrest 1 rotates at a larger angle, thus preventing back rubbing and making the user experience more comfortable.
[0081] A transmission component 320 connects the seat support 3 and the sliding member 430. The front end of the transmission component 320 is hinged to the rear end of the seat support 3, and the rear end of the transmission component 320 is hinged to the sliding member 430. The seat support 3, backrest support 4, sliding member 430, and transmission component 320 together form a structure similar to a three-bar linkage and a sliding groove. When the backrest support 4 rotates downward, the sliding member 430 is forced to slide forward due to the restriction of the transmission component 320; when the backrest support 4 rotates upward, the sliding member 430 is forced to slide backward due to the restriction of the transmission component 320. Thus, by setting the transmission component 320, the movement of the sliding member 430 is further restricted, making the movement of the sliding member 430 more stable and smooth.
[0082] Please refer to Figures 15-18. In some embodiments of this application, a gear adjustment member 440 is fixedly connected to the sliding support 420. A gear adjustment mechanism is provided between the sliding member 430 and the gear adjustment member 440. The gear adjustment mechanism includes a locking head 441 and a plurality of gear slots 431. The locking head 441 is disposed in one of the sliding member 430 and the gear adjustment member 440, and the plurality of gear slots 431 are disposed in the other of the sliding member 430 and the gear adjustment member 440. When the sliding member 430 slides back and forth relative to the gear adjustment member 440, the locking head 441 engages with the plurality of gear slots 431 in sequence.
[0083] In this embodiment, the sliding member 430 and the gear adjustment member 440 are adjusted through the locking head 441 and the gear groove 431, so that the sliding member 430 can be fixed at any position on the sliding support part 420, thereby enabling the backrest 1 to adjust and fix the tilt angle with the help of the gear adjustment mechanism, making it more convenient to use.
[0084] Please refer to Figures 15-18. In some embodiments of this application, the locking head 441 is movably connected to the gear adjustment member 440, and the sliding member 430 is provided with a plurality of gear slots 431. The gear adjustment mechanism has a switchable fixed state and a sliding state. In the fixed state, the locking head 441 slides outward to engage with the gear slot 431, so that the sliding member 430 and the gear adjustment member 440 are relatively fixed. In the sliding state, the locking head 441 slides inward to retract into the gear adjustment member 440 and avoid the gear slot 431, so that the sliding member 430 can slide relative to the gear adjustment member 440 again.
[0085] In this embodiment, by movably setting the locking head 441 on the gear adjustment member 440, and by using the movement of the locking head 441 to engage or avoid the gear slot 431, the movement or fixation between the sliding member 430 and the sliding support part 420 is realized, which facilitates operation and makes the gear adjustment operation more convenient.
[0086] Referring to Figures 17-18, the sliding member 430 has a plate-like structure. The bottom end of the sliding member 430 is recessed upwards to form a second sliding support groove 433 extending along its length. The gear adjustment member 440 is disposed within the second sliding support groove 433, and the sliding member 430 slides back and forth relative to the gear adjustment member 440 through the second sliding support groove 433, resulting in a better connection strength and more stable sliding process. The gear adjustment member 440 has locking heads 441 on both its left and right sides, and the left and right sides of the second sliding support groove 443 correspondingly have gear grooves 431. The gear adjustment component 440 has a hollow structure, including an internal receiving cavity 443. One end of the left and right side clips 441 passes through the side wall of the gear adjustment component 440 and extends into the receiving cavity 443. Two torsion springs 444 are provided symmetrically inside the receiving cavity 443. One side arm of the two torsion springs 444 is connected to the clips 441 on both sides, and the other side arm of the two torsion springs 441 is connected to the push-pull component 445. The push-pull component 445 can slide back and forth in the receiving cavity 443, and drive the torsion springs 444 to pull inward or push the clips 441. The chair seat 2 is also equipped with a wired control mechanism, including an adjustment switch 230 and a pull cord. One end of the pull cord is connected to the adjustment switch 230, and the other end passes through the gear adjustment component 440 and is connected to the push-pull component 445. When the adjustment switch 230 is turned on, the pull cord pulls the push-pull component 445 forward, which in turn drives the torsion spring 444 to pull the locking head 441 inward, thereby allowing the sliding component 430 to slide relative to the gear adjustment component 440 again. The rear end of the push-pull component 445 is also connected to a second... The fourth elastic element 446 constantly pulls the push-pull element 445, causing it to always have a tendency to slide backward. Therefore, when the adjustment switch 230 is closed, the pull rope releases the push-pull element 445, and under the elastic force of the fourth elastic element 446, the push-pull element 445 automatically slides backward to reset, driving the torsion spring 444 to push the locking head 441 outward, causing the locking head 441 to re-engage in the gear position slot 431, and the sliding element 430 to be re-fixed to the gear position adjustment element 440. Thus, the locking and unlocking of the gear position adjustment mechanism can be controlled by a wired control mechanism, making operation relatively simple.
[0087] Preferably, the slider 430 is provided with four rows of gear slots 431 along its length, so that the gear adjustment mechanism has four adjustable gears, providing a high degree of adjustment freedom. Of course, in other embodiments of this application, the number of gear slots 431 on the slider 430 can also be three, five, six, etc.
[0088] Please refer to Figure 15. In some embodiments of this application, the slider 430 is a plate-shaped structure. A first sliding support groove 432 extending in the front-back direction is hollowed out on the slider 430. A gear adjustment member 440 is slidably connected to the slider 430. A limiting part 442 is protruded on the gear adjustment member 440. The limiting part 442 passes through the first sliding support groove 432 and is connected to the sliding support part 420, so that the slider 430 is clamped between the sliding support part 420 and the gear adjustment member 440, and the slider 430 slides back and forth relative to the limiting part 442 through the first sliding support groove 432.
[0089] In this embodiment, the sliding member 430 is clamped by the sliding support part 420 and the gear adjustment part 440, and the sliding distance of the sliding member 430 is limited by the limiting part 442 and the first sliding support groove 432. This not only makes the connection strength between the sliding member 430 and the sliding support part 420 higher, but also makes the sliding process of the sliding member 430 more stable and smooth.
[0090] Preferably, the gear shift adjustment component 440 has two symmetrically protruding limiting portions 442, and the sliding component 430 has two correspondingly hollowed-out first sliding support grooves 432, further enhancing the connection strength between the sliding component 430 and the gear shift adjustment component 440. After the limiting portions 442 pass through the first sliding support grooves 432, the gear shift adjustment component 440 and the sliding support portion 420 are fixed together by screws, so that the sliding component 430, the gear shift adjustment component 440, and the sliding support portion 420 are detachably connected to each other, making the installation and disassembly of the chassis more convenient.
[0091] Please refer to Figures 2-4. In some embodiments of this application, the lower end of the seat 2 is provided with two symmetrical chassis connecting parts 210. The two chassis connecting parts 210 are attached to the left and right sides of the seat support part 3. The chassis connecting parts 210 and the seat support part 3 are connected by a guide mechanism. The guide mechanism includes a guide groove 211 and a guide pin 301 that slide against each other. The guide groove 211 is provided in one of the chassis connecting parts 210 and the seat support part 3, and the guide pin 301 is provided in the other of the chassis connecting parts 210 and the seat support part 310.
[0092] In this embodiment, by setting a guide structure between the chassis connection part 210 and the seat support part 3, the seat 2, the short support rod 510, the seat support part 3 and the guide groove 211 form a structure similar to a three-bar linkage and a sliding groove. With the help of the sliding of the guide pin 301 in the guide groove 211, the seat 2 slides up and down relative to the seat support part 3 and rotates back and forth in conjunction with the short support rod 510. The structure is simple and makes the transmission process between the seat 2 and the short support rod 510 more stable and smooth.
[0093] Of course, in other embodiments of this application, the chair seat 2, the short support rod 510 and the chair seat support 3 can also be driven by other mechanisms. For example, another auxiliary support rod can be hinged between the chair seat 2 and the chair seat support 3, so that the auxiliary support rod, the chair seat 2, the short support rod 510 and the chair seat support 3 form a mechanism similar to a four-bar linkage, so that when the chair seat 2 slides up and down relative to the chair seat support 3, the short support rod 510 and the auxiliary support rod can be driven to rotate back and forth together.
[0094] Please refer to Figures 2-4. In some embodiments of this application, the guide groove 211 includes a waist support guide portion 211a and a tilt guide portion 211b. Both the waist support guide portion 211a and the tilt guide portion 211b are inclined, with the inclination direction from front to back and from low to high. The inclination of the waist support guide portion 211a relative to the horizontal plane is greater than that of the tilt guide portion 211b.
[0095] In this embodiment, by tilting the guide groove 211, the position of the seat 2 in the horizontal direction changes when it slides up and down. The tilt of the lumbar support guide 211a is greater than that of the tilt guide 211b. This makes the change in the horizontal direction of the seat 2 smaller in the adaptive lumbar support state, thus avoiding affecting the seat depth adjustment. In the self-weight tilting state, the seat 2 will move a longer distance in the horizontal direction to adapt to the change in the position of the human buttocks when the backrest 1 is tilted back, making the support experience more comfortable.
[0096] Please refer to Figures 1-2. In some embodiments of this application, the short support rod 510 is hinged to the front end of the seat 2, the chassis connection part 210 is disposed at the rear end of the seat 2, and the guide groove 211 is formed in the chassis connection part 210.
[0097] In this embodiment, the rotating support rod 5 is hinged to the front side of the base, the short support rod 510 is hinged to the front end of the seat 2, and the chassis connection part 210 is set at the rear end of the seat 2, so that the seat 2 can be located exactly above the base, which is more reasonable. By opening the guide groove 211 in the chassis connection part 210, it is easy to process and will not affect the merging between the seat support part 3 and the backrest support part 4.
[0098] In other embodiments of this application, if the rotating support rod 5 is connected to the rear side of the base, the short support rod 510 can be hinged to the rear end of the seat 2, and the chassis connection part 210 is provided at the front end of the seat 2. Furthermore, the guide groove 211 can also be provided in the seat support part 3.
[0099] Please refer to Figures 8-9. In some embodiments of this application, a third elastic member 220 is provided between the seat 2 and the seat support 3. In the initial state, the third elastic member 220 does not apply elastic force to the seat 2 and the seat support 3. In the adaptive lumbar support state, the third elastic member 220 applies a pushing force to the seat 2 and the seat support 3, causing the seat 2 to tend to move away from the seat support 3. In the self-weight reclining state, the third elastic member 220 applies a pulling force to the seat 2 and the seat support 3, causing the seat 2 to tend to move closer to the seat support 3. This allows the seat 2 to automatically reset with the help of the elastic force of the third elastic member 220 when the user no longer needs to use the seat or needs to switch states. The seat 2 then rotates the support rod 5, the backrest support 4, the rear bracket 6, and the backrest 1, thereby resetting the dual-system seat to its initial state without requiring manual reset by the user, further improving the convenience of switching states of the dual-system seat.
[0100] Please refer to Figures 1-8. In some embodiments of this application, the third elastic element 220 is a controllable gas spring. The seat 2 and the third elastic element 220 are connected by a wire control mechanism. The wire control mechanism includes an adjustment switch 230 and a pull rope connected between the adjustment switch 230 and the third elastic element 220. The adjustment switch 230 is configured to adjust the pull rope to pull or release the pin of the third elastic element 220, thereby allowing the third elastic element 220 to be fixed at any telescopic length.
[0101] In this embodiment, by using a controllable gas spring, not only can elastic force be applied to the seat 2, but it can also be fixed at any extension length, thereby fixing the position of the seat 2. The short support rod 510 is also restricted from rotating by the seat 2, which in turn causes the long support rod 520 to remain fixed, thus fixing the front and back position of the backrest 1. Furthermore, the third elastic element 220 is controlled by a wired control mechanism, and the extension or fixation of the third elastic element 220 can be adjusted simply by pressing the adjustment switch 230, making the adjustment operation very convenient.
[0102] The adjustment switch 230 controls not only the third elastic element 220 but also the push-pull element 445 within the gear shift adjustment element 440. When the adjustment switch 230 is turned on, the third elastic element 220 can retract, allowing the backrest 1 to move forward and backward. The push-pull element 445 pulls down the torsion spring 444, causing the locking head 441 to retract inward. The sliding element 430 can slide forward and backward, adjusting the reclining angle of the backrest 1, thus allowing the backrest 1 to be adjusted. When the adjustment switch 230 is closed, the length of the third elastic element 220 is fixed, the forward and backward position of the backrest 1 is fixed, and the push-pull element 445 releases the torsion spring 444, causing the locking head 441 to pop out. The sliding element 430 is fixed in position, preventing the backrest 1 from rotating to adjust its reclining angle, thus keeping the backrest 1 fixed. Therefore, by pressing the adjustment switch 230, the overall fixation or movement of the backrest 1 can be controlled, further improving the ease of operation of the dual-system seat adjustment.
Claims
1. A dual-system seat, characterized in that, include: Backrest (1), configured to support the user's back; The seat (2) is configured to support the user when seated; The base is a split structure, including a seat support (3) and a back support (4) that are spliced together. The front end of the seat support (3) and the front end of the back support (4) are hinged to each other, so that the back support (4) can rotate up and down relative to the seat support (3). A rotating support rod (5) is provided on the left and right sides of the front end of the seat support part (3). The rotating support rod (5) includes a short support rod (510) and a long support rod (520) that are inclined to each other and always remain relatively fixed. The part where the lower ends of the short support rod (510) and the long support rod (520) meet is the rotating part (530). The rotating support rod (5) is hinged to the seat support part (3) through the rotating part (530), so that the rotating support rod (5) can rotate synchronously around the rotating part (530). The upper end of the long support rod (520) is hinged to the backrest (1), and the upper end of the short support rod (510) is hinged to the seat (2). The seat (2) can slide up and down relative to the seat support part (3) and drive the short support rod (510) to rotate back and forth around the rotating part (530). The rear support (6) is hinged at the rear end of the backrest support (4) and at the upper end of the rear support (6) is hinged to the backrest (1). The dual-system seat has a switchable initial state, an adaptive lumbar support state, and a self-weight reclining state. In the initial state, the seat (2) is not compressed and is in a high position, while the backrest (1) is not subjected to reclining force and remains upright. In the initial state, when the seat (2) is compressed and moves downwards, the dual-system seat switches to the adaptive lumbar support state. The short support rod (510) and the long support rod (520) are driven forward synchronously by the seat (2), and the rear support (6) responds to the long support rod (520) by swinging forward synchronously, thereby causing the hinged joint between the long support rod (520) and the seat (2) to... The backrest (1) on the upper side of the rear support (6) is driven to move forward and push out; in the initial state, when the backrest (1) is subjected to a reclining force, the dual-system seat switches to a self-weight reclining state, the backrest support (4) rotates downward relative to the backrest support (3), the backrest (1) responds to the backrest support (4) and rotates downward synchronously, and the long support rod (4) and the rear support (6) rotate backward synchronously, so that the upper backrest (1) can recline backward, and the short support rod (510) and the long support rod (520) swing backward synchronously, and drive the seat (2) to move upward.
2. The dual-system seat according to claim 1, characterized in that, In the adaptive lumbar support state, the backrest (1) moves 0-15cm in the horizontal direction; in the self-weight tilting state, the tilting angle of the backrest (1) is 0-30°.
3. The dual-system seat according to claim 1, characterized in that, A locking device is provided between the seat support (3) and the backrest support (4), and the locking device has a switchable locked state and an unlocked state; when the dual-system seat is switched to the adaptive lumbar support state, the locking device is in the locked state, and the seat support (3) and the backrest support (4) are relatively fixed. When the dual-system seat switches to the self-weight reclining state, the locking device is in the unlocked state, and the backrest support (4) can rotate again relative to the seat support (3).
4. The dual-system seat according to claim 3, characterized in that, The front end of the seat support (3) is provided with a first connecting part (310), and the front end of the backrest support (4) is provided with a second connecting part (410). The first connecting part (310) is hinged to the second connecting part (410). The first connecting part (310) has a first limiting hole (311) hollowed out along the left and right sides, and the second connecting part (410) has a second limiting hole (411) hollowed out along the left and right sides. The locking device includes a locking pin (401), which is slidably connected to the first limiting hole (311) and the second limiting hole (411). Locked state When the first limiting hole (311) is connected to the second limiting hole (411), the locking pin (401) slides to simultaneously engage with the first limiting hole (311) and the second limiting hole (411), so that the second connecting part (410) cannot rotate relative to the first connecting part (310), and the seat support part (3) and the backrest support part (4) are relatively fixed; in the unlocked state, the locking pin (401) slides to avoid the first limiting hole (311) or the second limiting hole (411), and the backrest support part (4) can rotate again relative to the seat support part (3).
5. The dual-system seat according to claim 4, characterized in that, The front end of the backrest support (4) is provided with two symmetrical second connecting parts (410), which are hinged to the left and right sides of the first connecting part (310). The rotating parts (530) on both sides are respectively hinged to the two second connecting parts (410). The locking device also includes a pressing part (531), which is provided on the side of the rotating part (530) close to the second connecting part (410). In the adaptive lumbar support state, the rotating part (530) rotates forward, and the pressing part (531) rotates accordingly and pushes the locking pin (401) inward, so that the locking pin (401) slides inward until it is simultaneously engaged with the first limiting hole (311) and the second limiting hole (411), and the locking device enters the locked state, and the seat support part (3) and the backrest support part (4) are relatively fixed; in the self-weight tilting state, the rotating part (530) rotates backward, and the pressing part (531) rotates accordingly and avoids the locking pin (401), so that the locking pin (401) slides outward until it is disengaged from the first limiting hole (311), and the locking device enters the unlocked state, so that the backrest support part (4) can rotate downward relative to the seat support part (3) again.
6. The dual-system seat according to claim 5, characterized in that, A first elastic element (402) is provided in the second limiting hole (411). The first elastic element (402) acts on the locking pin (401) and makes the locking pin (401) always have a tendency to move away from the first connecting part (310).
7. The dual-system seat according to claim 5, characterized in that, The end face of the pressing part (531) near the locking pin (401) and / or the end face of the locking pin (401) near the pressing part (531) are inclined, so that when the rotating part (530) drives the pressing part (531) to make a circular motion and pushes the locking pin (401), the locking pin (401) can slide towards the first connecting part (310) along the inclined direction of the end face.
8. The dual-system seat according to claim 1, characterized in that, A second elastic member (403) is provided between the seat support (3) and the backrest support (4). The two ends of the second elastic member (403) act on the seat support (3) and the backrest support (4) respectively, so that the backrest support (4) always has a tendency to rotate toward the seat support (3).
9. The dual-system seat according to claim 1, characterized in that, The backrest support (4) includes a sliding support (420) extending rearward from the rear end and a sliding member (430) slidably connected to the sliding support (420) along the front-rear direction. The bottom end of the rear support (6) is hinged to the sliding member (430). In the self-loaded tilting state, the sliding member (430) is subjected to pressure from the rear support (6) and slides forward. The bottom end of the rear support (6) is driven by the sliding member (430) and slides forward, causing the top end of the rear support (6) to rotate backward and drive the backrest (1) hinged to the top end of the rear support (6) to tilt further backward.
10. The dual-system seat according to claim 9, characterized in that, A gear adjustment component (440) is fixedly connected to the sliding support (420). A gear adjustment mechanism is provided between the sliding component (430) and the gear adjustment component (440). The gear adjustment mechanism includes a locking head (441) and a plurality of gear slots (431). The locking head (441) is disposed in one of the sliding component (430) and the gear adjustment component (440), and the plurality of gear slots (431) are disposed in the other of the sliding component (430) and the gear adjustment component (440). When the sliding component (430) slides back and forth relative to the gear adjustment component (440), the locking head (441) engages with the plurality of gear slots (431) in sequence.
11. The dual-system seat according to claim 10, characterized in that, The locking head (441) is movably connected to the gear adjustment member (440), and the sliding member (430) is provided with a plurality of gear slots (431). The gear adjustment mechanism has a switchable fixed state and a sliding state. In the fixed state, the locking head (441) slides outward to engage with the gear slot (431), so that the sliding member (430) and the gear adjustment member (440) are relatively fixed. In the sliding state, the locking head (441) slides inward to retract into the gear adjustment member (440) and avoid the gear slot (431), so that the sliding member (430) can slide relative to the gear adjustment member (440) again.
12. The dual-system seat according to claim 9, characterized in that, The sliding member (430) has a plate-like structure. A first sliding support groove (432) extending in the front-back direction is hollowed out on the sliding member (430). A gear adjustment member (440) is slidably connected to the sliding member (430). A limiting part (442) is protruded on the gear adjustment member (440). The limiting part (442) passes through the first sliding support groove (432) and is connected to the sliding support part (420), so that the sliding member (430) is clamped between the sliding support part (420) and the gear adjustment member (440), and the sliding member (430) slides back and forth relative to the limiting part (442) through the first sliding support groove (432).
13. The dual-system seat according to claim 1, characterized in that, The lower end of the seat (2) is provided with two symmetrical chassis connecting parts (210). The two chassis connecting parts (210) are attached to the left and right sides of the seat support part (3). The chassis connecting parts (210) and the seat support part (3) are connected by a guide mechanism. The guide mechanism includes a guide groove (211) and a guide pin (301) that slide with each other. The guide groove (211) is provided in one of the chassis connecting parts (210) and the seat support part (3), and the guide pin (301) is provided in the other of the chassis connecting parts (210) and the seat support part (310).
14. The dual-system seat according to claim 13, characterized in that, The guide groove (211) includes a waist support guide (211a) and a tilt guide (211b). Both the waist support guide (211a) and the tilt guide (211b) are inclined in the direction from front to back and from low to high. The inclination of the waist support guide (211a) relative to the horizontal plane is greater than that of the tilt guide (211b).
15. The dual-system seat according to claim 13, characterized in that, The short support rod (510) is hinged to the front end of the seat (2), the chassis connection part (210) is located at the rear end of the seat (2), and the guide groove (211) is opened in the chassis connection part (210).
16. The dual-system seat according to claim 1, characterized in that, A third elastic element (220) is provided between the seat (2) and the seat support (3). In the initial state, the third elastic element (220) does not apply elastic force to the seat (2) and the seat support (3). In the adaptive lumbar support state, the third elastic element (220) applies a pushing force to the seat (2) and the seat support (3), causing the seat (2) to tend to move away from the seat support (3); in the self-weight tilting state, the third elastic element (220) applies a pulling force to the seat (2) and the seat support (3), causing the seat (2) to tend to move closer to the seat support (3).
17. The dual-system seat according to claim 16, characterized in that, The third elastic element (220) is a controllable gas spring. The seat (2) and the third elastic element (220) are connected by a wire control mechanism. The wire control mechanism includes an adjustment switch (230) and a pull rope connected between the adjustment switch (230) and the third elastic element (220). The adjustment switch (230) is configured to adjust the pull rope to pull or release the pin of the third elastic element (220), thereby allowing the third elastic element (220) to be fixed at any telescopic length.