Seat

Abstract

The invention discloses a seat which comprises an armrest frame, the armrest frame is divided into at least four parts to form a four-connecting-rod mechanism, an arm supporting piece is used for supporting an arm, a movable connecting rod piece provides a closed loop for linkage of the four-connecting-rod mechanism, and a fixed connecting rod piece is used for being connected with a supporting base of a seat, such as a lifting air rod. The fixed connecting rod piece can be kept static relative to the ground, the driving connecting rod piece is used for installing the backrest and serves as a driving piece in the four-connecting-rod mechanism, the four connecting rod pieces are sequentially hinged end to end to form the four-connecting-rod mechanism, and when the backrest is pushed by a user to fall down, the driving connecting rod piece and the backrest make backward tipping movement together. The driving connecting rod piece pulls the arm supporting piece to move backwards at the same time, the fixed connecting rod piece is different, and the movable connecting rod piece only rotates backwards on the fixed connecting rod piece when being pulled by the arm supporting piece. And meanwhile, chassis removal and linkage of the seat backrest, the seat part and the armrests are realized, so that the comfort is improved, and the aesthetic feeling is increased.

Description

Technical Field

[0001] This invention relates to the field of furniture, and more particularly to a seating arrangement for sitting. Background Technology

[0002] In the field of seating, the chassis is a functional module that is usually set separately under the seat. Its main functions are to realize the tilting of the backrest, the adjustment of the lifting gas spring, or the movement of the seat, and it has gradually become an indispensable part of modern seating.

[0003] However, the presence of the chassis affects the appearance of the chair to some extent. Its large size and thickness are very conspicuous when placed on the chair, and the visual feeling is very abrupt. This is especially true for light luxury office chairs that pay more attention to appearance. The abrupt chassis disrupts the minimalist style. Although it provides the basis for changing the position of the chair in terms of function, it fails to attract consumers in terms of appearance.

[0004] Furthermore, in the realm of luxury office chairs, the seats and backrests are typically made of foam-covered leather, while connecting components such as armrests and five-star bases are made of aluminum alloy frames to achieve a premium feel. Compared to regular ergonomic chairs, these chairs lack mobility. In particular, there is a type of luxury office chair with framed armrests. In this type of chair, the framed armrests fix the seat and backrest together. Even with a base, only the seat and backrest can tilt synchronously. The excessively raised front of the seat can compress the thighs, leading to leg discomfort. In other words, this type of chair cannot achieve relative rotation between the backrest and seat, or a more ergonomic linkage, thus failing to provide users with a comfortable resting experience.

[0005] Considering that the chassis becomes less functional in some types of seats, affecting both appearance and functionality, how to remove the chassis while retaining the seat-back linkage function is a problem we urgently need to solve. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a seating arrangement including an armrest frame divided into at least four parts, forming a four-bar linkage. An armrest support supports the arms, a movable link provides a closed loop for the four-bar linkage, a fixed link connects to the seat's support base (e.g., a gas lift), and remains stationary relative to the ground. A drive link mounts the backrest and acts as the active component in the four-bar linkage. The four links are sequentially hinged end-to-end to form the four-bar linkage. When the backrest is pushed by the user leaning back, the drive link tilts backward along with the backrest, simultaneously pulling the armrest backward while the fixed link remains stationary. When the movable link is pulled by the armrest, it only rotates backward along the fixed link. This design achieves chassis-free operation and linkage between the seat back, seat, and armrests, enhancing both comfort and aesthetics.

[0007] The technical solution of this invention is implemented as follows: A seating arrangement includes an armrest frame, comprising an arm support member, a movable link member, a fixed link member, and a drive link member rotatably connected in sequence. The fixed link member includes a base located at its lower end, configured to connect with a support base of the seat, and the drive link member is rotatably connected to the base. The arm support member is arranged along the front-to-back direction at the upper end of the armrest frame and configured to support an arm. The movable link member and the drive link member are spaced apart along the front-to-back direction, with the drive link member located at the rear. The fixed link member is located at the lower end of the armrest frame, and the drive link member is linked with the arm support member and the movable link member. A backrest is provided on the drive link member, and a seat portion is movably provided on the movable link member and the fixed link member. When the backrest member is reclined, it drives the drive link member to move, causing the armrest frame to move, and the arm support member and the seat portion to move accordingly.

[0008] In this design, the armrest frame is divided into at least four parts, forming a four-bar linkage. The arm support supports the arms, the movable link provides a closed loop for the linkage, the fixed link connects to the seat's support base (e.g., a gas lift), and remains stationary relative to the ground. The drive link mounts the backrest and acts as the active component in the four-bar linkage. The four links are sequentially hinged end-to-end to form the four-bar linkage. When the backrest is pushed by the user leaning back, the drive link tilts backward along with the backrest, simultaneously pulling the arm support backward. The fixed link remains stationary. When the movable link is pulled by the arm support, it only moves backward along the fixed link. The drive linkage also rotates backward on the fixed linkage. However, since the drive linkage and the fixed linkage are not parallel, the arm support between them does not move in parallel either, but will also tilt to a certain extent. After the size ratio of the drive linkage and the fixed linkage, the tilt of the arm support is a downward rotation at the front end. The seat located between the drive linkage and the fixed linkage will also be driven by the drive linkage to move backward and tilt. Therefore, this solution not only achieves seat-back linkage while eliminating the chassis and increasing aesthetics, thus improving the comfort of the seat, but also enables the armrests to move in tandem, so that the armrests can have an ergonomic posture when sitting or resting.

[0009] Preferably, the drive link is located behind the fixed link, the lower end of the drive link is rotatably connected to the base, the upper end of the drive link is rotatably connected to the rear end of the arm support, the front end of the arm support is rotatably connected to the upper end of the movable link, and the lower end of the movable link is rotatably connected to the upper end of the fixed link.

[0010] Preferably, the chair has an upright sitting position and a reclining position. In the upright sitting position, the backrest is vertical, and the armrests and seat are horizontal. When switching from the upright sitting position to the reclining position, the backrest tilts backward, and both the armrests and seat move backward. At the same time, the front of the armrests tilts downward, and the rear of the seat tilts downward. In both positions, the posture of the backrest, armrests, and seat is more ergonomic. Especially in the reclining position, the backrest tilts backward, and the armrests tilt downward from back to front, allowing the user's arms to rest naturally and comfortably on them. The seat also tilts slightly downward from front to back, increasing the comfort of sitting in the reclining position.

[0011] Preferably, the seat is suspended above the armrest frame, with a cantilevered space between the base and the seat in the vertical direction. A first, upward-protruding mounting seat is provided on the drive linkage, and a second, upward-protruding mounting seat is provided on the fixed linkage. The first mounting seat connects to the rear of the seat, and the second mounting seat connects to the front of the seat. The suspended seat emphasizes its slimness and enhances its aesthetics. Because the seat is chassis-free, with no base installed beneath it, the overall thickness of the seat is thinner and more slender. Furthermore, the suspended design further highlights the difference between this seat and existing seats.

[0012] Preferably, the drive linkage includes a rotating part rotatably connected to the base. The rotating part has a first inclined rod extending obliquely rearward and upward. The first inclined rod has a vertically arranged vertical rod for mounting the backrest, and the first mounting seat is disposed on the first inclined rod. The fixed linkage also includes a second inclined rod extending obliquely forward and upward from the front end of the base, and the second mounting seat is disposed on the second inclined rod. Both the first and second inclined rods are beneficial for suspending the seat portion. In addition to enhancing aesthetics, suspending the seat portion also helps prevent interference between the seat portion and the drive linkage and the base.

[0013] Preferably, both the drive linkage and the fixed linkage are branched. There are two first diagonal rods, each branching out to the left and right on the rotating part and connected to the seat. Similarly, there are two second diagonal rods, each branching out to the left and right on the base and connected to the seat. The branched drive linkage and fixed linkage have four connection points with the seat, making the connection more stable and ensuring the seat remains stable when supporting a person.

[0014] Preferably, a tilting elastic element is also included. This tilting elastic element is configured to provide a spring force for the backrest to rotate forward. The tilting elastic element is positioned between the drive linkage and the fixed linkage. One end of the tilting elastic element is linked to the drive linkage, while the other end remains relatively stationary with respect to the fixed linkage. When the backrest tilts backward, the tilting elastic element deforms and generates a spring force. During the backward rotation of the backrest, the tilting elastic element provides a cushioning spring force to prevent the backrest from tilting too quickly, maintaining a comfortable backward tilt speed. During the forward rotation of the backrest, the tilting elastic element provides a restoring spring force to help the user return to an upright sitting position.

[0015] Preferably, the tilting elastic element is a telescopic spring, which is located in the seat and one end is connected to the seat. A connecting piece is provided on the fixed linkage, and the other end of the tilting elastic element is connected to the connecting piece. When the backrest tilts backward, the seat moves backward and stretches the tilting elastic element. Since the tilting elastic element counteracts the force of the human body, its size is generally large. In this design, the tilting elastic element is located in the seat, meaning that there is no need to install a tilting elastic element in the base, thus greatly reducing the volume of the base. Only components for controlling the gas spring and components for locking or unlocking the drive linkage are needed.

[0016] Preferably, the seat includes a bottom shell, a tilting elastic member is disposed above the bottom shell, the bottom shell has a clearance groove arranged in the front-rear direction, and the connecting member enters the bottom shell from the clearance groove and connects with the tilting elastic member.

[0017] Preferably, the bottom shell is equipped with a guide rail, and the connecting member is equipped with rollers. The rollers are located inside the bottom shell and abut against the guide rail. The rollers reduce wear and make the movement of the seat and the fixed connecting rod smoother.

[0018] Preferably, the pitching elastic element is a torsion spring, which is disposed within the base. The pitching elastic element includes two spring arms, which are respectively connected to the base and the drive linkage. Alternatively, the pitching elastic element can be disposed within the base, but this would increase the volume of the base.

[0019] Preferably, the backrest includes a sleeve portion with a slot, the sleeve portion being fitted onto a drive linkage, and the drive linkage being inserted into the slot.

[0020] Preferably, the drive linkage includes a main rod and a split rod, with the split rod inserted into the upper end of the main rod. The split rod is configured so that, when separated from the main rod, a sleeve portion can be fitted onto the upper end of the main rod. This allows the backrest to be mounted onto the enclosed armrest frame.

[0021] The design starting point, concept, and beneficial effects of the present invention, which adopts the above technical solution, are as follows: In this design, the armrest frame is divided into at least four parts, forming a four-bar linkage. The arm support supports the arms, the movable link provides a closed loop for the linkage, the fixed link connects to the seat's support base (e.g., a gas lift), and remains stationary relative to the ground. The drive link mounts the backrest and acts as the active component in the four-bar linkage. The four links are sequentially hinged end-to-end to form the four-bar linkage. When the backrest is pushed by the user leaning back, the drive link tilts backward along with the backrest, simultaneously pulling the arm support backward. The fixed link remains stationary. When the movable link is pulled by the arm support, it only moves backward along the fixed link. The drive linkage also rotates backward on the fixed linkage. However, since the drive linkage and the fixed linkage are not parallel, the arm support between them does not move in parallel either, but will also tilt to a certain extent. After the size ratio of the drive linkage and the fixed linkage, the tilt of the arm support is a downward rotation at the front end. The seat located between the drive linkage and the fixed linkage will also be driven by the drive linkage to move backward and tilt. Therefore, this solution not only achieves seat-back linkage while eliminating the chassis and increasing aesthetics, thus improving the comfort of the seat, but also enables the armrests to move in tandem, so that the armrests can have an ergonomic posture when sitting or resting. Attached Figure Description

[0022] Figure 1 This is a three-dimensional structural diagram of the seat in the upright sitting state of the present invention. Figure 2 This is a side view of the seat in an upright sitting position according to an embodiment of the present invention; Figure 3 This is a three-dimensional structural diagram of the seat in the reclining state in an embodiment of the present invention; Figure 4 This is a side view of the seat in a reclining position according to an embodiment of the present invention; Figure 5 This is a three-dimensional structural diagram of the armrest frame in the upright sitting state of the present invention. Figure 6 This is a side view of the armrest frame in an upright sitting position according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the backrest and drive linkage assembly in an embodiment of the present invention; Figure 8 This is a schematic diagram of the three-dimensional structure of the present invention, in an embodiment, where the tilting elastic element is installed within the base plate. Figure 1 ; Figure 9 This is a schematic diagram of the three-dimensional structure of the present invention, in an embodiment, where the tilting elastic element is installed within the base plate. Figure 2 ; Figure 10 This is a schematic diagram illustrating the state changes of the seat in an embodiment of the present invention; Figure 11 This is an exploded view of the driving link and the fixed link in an embodiment of the present invention; Figure 12 This is a three-dimensional structural diagram of the fixed connecting rod in an embodiment of the present invention; Figure 13 This is a side view of the armrest frame in the reclining state of the present invention in an embodiment; Figure 14 This is a three-dimensional structural diagram of the armrest frame in the reclining state of the present invention in an embodiment.

[0023] The attached figures are labeled as follows: 1. Armrest frame; 2. Arm support; 3. Movable link; 4. Fixed link; 5. Drive link; 6. Base; 7. Backrest; 8. Seat; 10. Lifting gas spring; 11. Five-star base; 12. Sleeve; 13. Main rod; 14. Split rod; 15. First mounting base; 16. Second mounting base; 17. Rotating part; 18. First inclined rod; 19. Vertical rod; 20. Second inclined rod; 21. Tilting elastic element; 22. Connector; 23. Bottom shell; 24. Clearance groove; 25. Guide rail; 26. Roller; 27. Detailed Implementation

[0024] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0025] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0026] In the description of this invention, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0027] The specific embodiments of the present invention are as follows: like Figure 1-6As shown in Figures 13 and 14, the present invention provides a seating device, including an armrest frame 1. The armrest frame 1 includes an arm support member 2, a movable connecting rod 3, a fixed connecting rod 4, and a drive connecting rod 5, which are rotatably connected in sequence. The fixed connecting rod 4 includes a base 6 located at its lower end, which is configured to be connected to the support base of the seat. The drive connecting rod 5 is rotatably connected to the base 6. The arm support member 2 is arranged in the front-to-back direction at the upper end of the armrest frame 1 and is configured to support the arm. The movable connecting rod 3 and the drive connecting rod 5 are arranged at intervals in the front-to-back direction, with the drive connecting rod 5 located at the rear. The fixed connecting rod 4 is located at the lower end of the armrest frame 1. The drive connecting rod 5 is linked with the arm support member 2 and the movable connecting rod 3. A backrest 7 is provided on the drive connecting rod 5. A seat portion 8 is movably provided on the movable connecting rod 3 and the fixed connecting rod 4. When the backrest 7 is tilted back, it drives the drive connecting rod 5 to move and causes the armrest frame 1 to move, and the arm support member 2 and the seat portion 8 move accordingly.

[0028] In this design, the armrest frame 1 is divided into at least four parts, forming a four-bar linkage. The arm support 2 supports the arm, the movable link 3 provides a closed loop for the four-bar linkage, the fixed link 4 connects to the seat's support base (such as the lifting gas spring 10) and remains stationary relative to the ground, and the drive link 5 mounts the backrest 7 and acts as the active component in the four-bar linkage. The four links are sequentially hinged end-to-end to form the four-bar linkage. When the backrest 7 is pushed by the user leaning back, the drive link 5 tilts backward along with the backrest 7, simultaneously pulling the arm support 2 backward. The fixed link 4 remains stationary, and the movable link 3 is pulled by the arm support 2. When in motion, the armrest rotates backward only on the fixed link 4; the drive link 5 also rotates backward on the fixed link 4, but since the drive link 5 and the fixed link 4 are not parallel, the arm support 2 between them does not move in parallel, but will tilt to a certain extent. The tilt of the arm support 2 is determined by the size ratio of the drive link 5 and the fixed link 4, resulting in a downward rotation at the front end; the seat 8 located between the drive link 5 and the fixed link 4 will also be driven by the drive link 5 to move backward and tilt. Therefore, this solution not only eliminates the chassis and increases aesthetics, but also achieves seat-back linkage, improves user comfort, and makes the armrests move together, so that the armrests can conform to the ergonomic posture when sitting or resting.

[0029] To further highlight the difference between the base 6 and the traditional chassis, the vertical length of the base 6 is 50-70mm, the front-to-back dimension is 90-120mm, and the left-to-right dimension is 60-70mm. In this embodiment, the vertical length of the base 6 is 65mm, the front-to-back dimension is 98mm, and the left-to-right dimension is 65mm. The smaller size of the base allows for smooth connection of the fixing rod 4 under the seat, resulting in a strong sense of unity and achieving the visual effect of having only rods and no chassis. This makes the base volume only 30% of that of a typical chassis, thus giving the seat a simple and refined appearance.

[0030] Specifically, such as Figure 1-4 As shown, this solution is not limited to light luxury office chairs. The seat's support base includes a lifting gas spring 10 and a five-star base 11. The base 6 is connected to the lifting gas spring 10, which is equivalent to realizing the function of connecting the lifting gas spring 10 in the chassis. The drive linkage 5 in the armrest frame 1 is used to install the backrest 7 and can rotate with the base 6, which is equivalent to realizing the function of connecting the backrest 7 and tilting the backrest 7 in the chassis. The seat 8 is connected to both the fixed linkage 4 and the drive linkage 5 and can move with the backrest 7. The angle between the backrest 7 and the seat 8 changes, which is equivalent to realizing the seat-back linkage function in the chassis. In summary, although the chassis is eliminated, the core functions of the chassis are retained through the new structural design.

[0031] like Figure 1 , 3 As shown in Figure 7, the driving link 5 is located behind the fixed link 4. The lower end of the driving link 5 is rotatably connected to the base 6, the upper end of the driving link 5 is rotatably connected to the rear end of the arm support 2, the front end of the arm support 2 is rotatably connected to the upper end of the movable link 3, and the lower end of the movable link 3 is rotatably connected to the upper end of the fixed link 4. Therefore, the armrest frame 1 is closed, and the backrest 7 is installed as follows: the backrest 7 includes a sleeve portion 12 with a slot 13. The sleeve 12 is mounted on the drive linkage 5, which is inserted into the slot 13. Further, the drive linkage 5 includes a main rod 14 and a split rod 15. The split rod 15 is inserted into the upper end of the main rod 14. The split rod 15 is configured so that when it is separated from the main rod 14, the sleeve part 12 can be fitted onto the upper end of the main rod 14. After the sleeve part 12 is fitted onto the main rod 14, the split rod 15 is then inserted and installed onto the main rod 14, thus completing the installation of the backrest 7 on the enclosed armrest frame 1.

[0032] Furthermore, such as Figure 1-4As shown in Figure 10, the chair has an upright sitting position and a reclining position: In the upright sitting position, the backrest 7 is vertical, and the arm support 2 and the seat 8 are horizontal or slightly tilted upwards; when switching from the upright sitting position to the reclining position, the backrest 7 tilts backwards, and the arm support 2 and the seat 8 both move backwards. At the same time, the front end of the arm support 2 tilts downwards, and the rear end of the seat 8 tilts downwards. In both positions, the posture of the backrest 7, the arm support 2, and the seat 8 are more ergonomic. Especially in the reclining position, the backrest 7 tilts backwards, the arm support 2 tilts downwards from back to front, and the user's arms can be placed naturally and comfortably on it. The seat 8 tilts slightly downwards from front to back, which can increase the sitting comfort when reclining.

[0033] The seat 8 is suspended above the armrest frame 1, and there is a cantilevered space between the base 6 and the seat 8 in the vertical direction; for example Figure 11 , 12 As shown, the drive linkage 5 has an upwardly protruding first mounting seat 16, and the fixed linkage 4 has an upwardly protruding second mounting seat 17. The first mounting seat 16 is connected to the rear of the seat 8, and the second mounting seat 17 is connected to the front of the seat 8. The suspended seat 8 emphasizes its slimness and enhances its aesthetics. Since the seat is chassis-free, there is no chassis installed under the seat 8, so the overall thickness of the seat 8 is thinner and slimmer. Combined with the suspended design, it further highlights the difference from existing seats. Furthermore, the drive linkage 5 includes a rotating part 18 that is rotatably connected to the base 6. The rotating part 18 is provided with a first inclined rod part 19 extending backward and upward at an angle. The first inclined rod part 19 is provided with a vertical rod part 20 for mounting the backrest 7. The first mounting seat 16 is disposed on the first inclined rod part 19. The fixed connecting rod 4 also includes a second inclined rod part 21, which extends forward and upward from the front end of the base 6 at an angle. The second mounting seat 17 is disposed on the second inclined rod part 21. The first inclined rod part 19 and the second inclined rod part 21 are also conducive to suspending the seat part 8 and can prevent the seat part 8 from interfering with the driving connecting rod 5 and the base 6.

[0034] Both the drive link 5 and the fixed link 4 are branched: there are two first diagonal rods 19, which are forked on the rotating part 18 and connected to the seat part 8; there are two second diagonal rods 21, which are forked on the base 6 and connected to the seat part 8; the branched structure forms a four-point connection when connected to the seat part 8, making the connection more stable and ensuring that the seat part 8 remains stable when supporting the human body; from the front, the armrest frame 1 is roughly U-shaped, and from the side it is roughly O-shaped.

[0035] like Figure 8 , 9As shown, the seat also includes a tilting elastic element 22, which is configured to provide a spring force for the backrest 7 to rotate forward. It is located between the drive linkage 5 and the fixed linkage 4, with one end linked to the drive linkage 5 and the other end remaining relatively stationary with the fixed linkage 4. When the backrest 7 tilts backward, the tilting elastic element 22 deforms and generates a spring force, which can both buffer the backward tilt of the backrest 7 to prevent rapid tilting and provide assistance when the backrest 7 returns to its forward position to help the user return to an upright sitting posture.

[0036] Specifically, the tilting elastic element 22 is a telescopic spring, installed in the seat 8, with one end connected to the seat 8; the fixed connecting rod 4 is provided with a connector 23, which is inserted and fixed in the second mounting base 17, and the other end of the tilting elastic element 22 is connected to the connector 23; when the backrest 7 tilts backward, the seat 8 moves backward accordingly and stretches the tilting elastic element 22; since the tilting elastic element 22 is usually large in size to resist the force of the human body, placing it in the seat 8 can significantly reduce the volume of the base 6 (only a small amount is needed in the base 6). (The components for controlling the gas spring and the components for locking / unlocking the drive linkage 5 to rotate are provided). The seat 8 includes a bottom shell 24, a tilt elastic member 22 is disposed above the bottom shell 24, the bottom shell 24 has a clearance groove 25 in the front-rear direction, and the connecting member 23 enters the bottom shell 24 from the clearance groove 25 and connects to the tilt elastic member 22; the bottom shell 24 is provided with a guide rail 26, and the connecting member 23 is provided with a roller 27. The roller 27 is located inside the bottom shell 24 and abuts against the guide rail 26, which can reduce wear and make the movement of the seat 8 and the fixed linkage 4 smoother.

[0037] In addition, the tilting elastic element 22 can also be a torsion spring, which can be set in the base 6 (in this case, the tilting elastic element 22 includes two spring arms, which are respectively connected to the base 6 and the drive linkage 5); however, setting it in the base 6 will increase the volume of the base 6. Therefore, in this embodiment, it is preferred to set the tilting elastic element 22 in the seat 8 - the seat 8 itself has a certain thickness, and it is only necessary to partially hollow it out to make room, which will not affect the overall thickness of the seat 8.

Claims

1. A seating arrangement, characterized in that: The armrest frame includes an arm support, a movable link, a fixed link, and a drive link, which are rotatably connected in sequence. The fixed link includes a base at its lower end, which is configured to connect to the support base of the seat. The drive link is rotatably connected to the base. The arm support is arranged at the upper end of the armrest frame in a front-to-back direction and is configured to support an arm. The movable link and the drive link are spaced apart in a front-to-back direction, with the drive link located at the rear. The fixed link is located at the lower end of the armrest frame. The drive link is linked with the arm support and the movable link. The drive link has a backrest, and the movable link and the fixed link have seats that are movably mounted on them. When the backrest is reclined, it moves the drive link and causes the armrest frame to move, and the arm support and the seat move accordingly.

2. The seating according to claim 1, characterized in that: The drive link is located behind the fixed link. The lower end of the drive link is rotatably connected to the base. The upper end of the drive link is rotatably connected to the rear end of the arm support. The front end of the arm support is rotatably connected to the upper end of the movable link. The lower end of the movable link is rotatably connected to the upper end of the fixed link.

3. The seating according to claim 1, characterized in that: The chair has an upright sitting position and a reclining position. In the upright sitting position, the backrest is vertical and the armrest is horizontal with the seat. When switching from the upright sitting position to the reclining position, the backrest tilts backward, and both the armrest and the seat move backward. At the same time, the front end of the armrest tilts downward and the rear end of the seat tilts downward.

4. The seating according to claim 1, characterized in that: The seat is mounted on the armrest frame with an open space between the base and the seat in the vertical direction. A first mounting seat with an upward protrusion is provided on the drive linkage, and a second mounting seat with an upward protrusion is provided on the fixed linkage. The first mounting seat is connected to the rear of the seat, and the second mounting seat is connected to the front of the seat.

5. The seating according to claim 4, characterized in that: The driving linkage includes a rotating part rotatably connected to the base. The rotating part has a first inclined rod extending obliquely backward and upward. The first inclined rod has a vertical rod for mounting the backrest and is arranged vertically. The first mounting seat is disposed on the first inclined rod. The fixing linkage also includes a second inclined rod extending obliquely forward and upward from the front end of the base. The second mounting seat is disposed on the second inclined rod.

6. The seating according to claim 5, characterized in that: Both the driving link and the fixed link are branched; there are two first oblique rods, which are arranged on the rotating part and connected to the seat; there are two second oblique rods, which are arranged on the base and connected to the seat.

7. The seating according to claim 1, characterized in that: It also includes a tilting elastic element, which is configured to provide a spring force for the backrest to rotate forward. The tilting elastic element is located between the drive linkage and the fixed linkage. One end of the tilting elastic element is linked to the drive linkage, and the other end of the tilting elastic element remains relatively stationary with respect to the fixed linkage. When the backrest tilts backward, the tilting elastic element deforms and generates a spring force.

8. The seating according to claim 7, characterized in that: The tilting elastic element is a telescopic spring, which is installed in the seat and one end of the tilting elastic element is connected to the seat. A connecting piece is provided on the fixed connecting rod, and the other end of the tilting elastic element is connected to the connecting piece. When the backrest tilts backward, the seat moves backward and stretches the tilting elastic element.

9. The seating according to claim 8, characterized in that: The seat includes a bottom shell, a tilting elastic member is disposed above the bottom shell, and the bottom shell has a clearance groove arranged in the front-to-back direction. The connecting member enters the bottom shell from the clearance groove and connects with the tilting elastic member.

10. The seating according to claim 9, characterized in that: The bottom shell is equipped with a guide rail, and the connecting part is equipped with a roller. The roller is located inside the bottom shell and abuts against the guide rail.

11. The seating according to claim 7, characterized in that: The pitching elastic element is a torsion spring, which is installed in the base. The pitching elastic element includes two spring arms, which are respectively connected to the base and the drive linkage.

12. The seating according to claim 1, characterized in that: The backrest includes a sleeve portion with a slot, which is fitted onto a drive linkage, which is inserted into the slot.

13. The seating according to claim 12, characterized in that: The drive linkage includes a main rod and a split rod. The split rod is inserted into the upper end of the main rod and is configured so that when separated from the main rod, the sleeve part can be fitted onto the upper end of the main rod.

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