Chair and backrest adjustment mechanism thereof

Abstract

The utility model discloses a chair and backrest adjusting mechanism thereof, include: backrest, chair seat, first handrail and second handrail. In the scheme, first handrail and second handrail fixed mounting are in the left and right sides of chair seat, and the first shell and the second shell of handrail are hinged with backrest, and the first slider and the second slider of movable connection with backrest are respectively set in the first shell and the second shell, and the relative position of first slider is locked or unlocked to the gas spring in first handrail through pressing piece, when needing to adjust backrest, the user only needs to press pressing piece to unlock gas spring, then leans back on backrest, and backrest drives first slider and second slider to move back, and the lower end of backrest rotates relative to first handrail and second handrail, thereby adjusting the depth and the angle of inclination of backrest simultaneously, and the position of backrest can be fixed by releasing pressing piece, and the adjusting mode is simple and reliable.

Description

Technical Field

[0001] This utility model relates to the field of seating technology, and in particular to a chair and its backrest adjustment mechanism. Background Technology

[0002] In daily life, both adults and children spend long periods of time sitting to work, study, or perform various duties. Because many users sit for extended periods, it's crucial to adjust the chair's recline angle appropriately for each user to provide greater comfort, and it's also important to prevent users from sitting in the same position for extended periods. Current technology typically involves a tray under the seat, with the backrest fixed to the tray. Adjusting the tray allows for backrest recline adjustment. However, this backrest recline adjustment mechanism is located under the seat, making it inconvenient for users to access and adjust while seated, requiring repeated adjustments to the seat depth and wasting considerable time. Patent application CN110522222A discloses a chair back adjustable armrest structure, which is adjusted by a connecting frame and a connecting armrest. The connecting teeth and moving groove in the connecting armrest allow the chair back to be adjusted to tilt angle and recline. However, when adjusting the chair back, the armrest needs to be moved up or down as a whole, and the user's arm also needs to move with the armrest. Moreover, after the chair back is adjusted, the user needs to press the armrest down to make the connecting teeth and moving groove engage. During engagement, there is a tendency for back-and-forth slippage and jerking, resulting in a poor user experience. Utility Model Content

[0003] In order to solve the above-mentioned technical problems, the purpose of this utility model is to provide a chair and its backrest adjustment mechanism. After pressing the button on the armrest, the user can adjust the backrest by leaning back. The operation is simple and the user experience is good.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A backrest adjustment mechanism, comprising:

[0006] Backrest;

[0007] Seat;

[0008] The first handrail includes a first housing and a first slider and a gas spring installed inside the first housing. The gas spring is connected to the first slider and can drive the first slider to move back and forth. The side wall of the first housing is provided with a button for triggering the gas spring.

[0009] The second handrail includes a second housing and a second slider installed inside the second housing, the second slider being able to slide back and forth inside the second housing;

[0010] The first armrest and the second armrest are fixedly connected to the left and right sides of the seat, respectively. The rear ends of the first shell and the second shell are hinged to the left and right sides of the backrest, respectively. The rear ends of the first slider and the second slider are movably connected to the left and right sides of the backrest, respectively.

[0011] Preferably, the inner wall of the first housing is provided with a first limiting hole, and the connecting part between the rear end of the first slider and the backrest is limited in the first limiting hole and can move back and forth along the first limiting hole; the inner wall of the second housing is provided with a second limiting hole, and the limiting part between the rear end of the second slider and the backrest is limited in the second limiting hole and can move back and forth along the second limiting hole.

[0012] Preferably, a third through hole is provided on the left or right side wall of the first outer casing, and the button is installed at the third through hole; a connecting seat is connected to the end of the piston rod of the gas spring away from the cylinder, the connecting seat is connected to the first slider, the connecting seat is provided with a swing block groove, and a swing block is hinged in the swing block groove. When the swing block swings to contact the piston rod, it can unlock the gas spring; a transmission line, a rotating block and a rotating seat are also provided inside the first outer casing. The rotating seat is installed at the third through hole, the rotating block is hinged to the rotating seat, the transmission line connects the rotating block and the swing block, the button passes through the third through hole and the rotating seat and is connected to the rotating block, and the external force acting on the button is transmitted to the swing block through the rotating block and the transmission line, thereby driving the swing block to swing.

[0013] Preferably, an elastic element for resetting the press is provided between the press and the rotating seat; an elastic element for resetting the rotating block is provided between the rotating seat and the rotating block; and / or an elastic element for resetting the swinging element is provided between the swinging block and the piston rod.

[0014] Preferably, the second slider is installed inside the second housing via a stop structure. The second housing has a first groove, and multiple stop slots are formed on the left or right side wall of the first groove. A U-shaped guide groove is formed on the bottom wall of the first groove. A guide member is provided inside the second housing. The guide member is hinged to the second slider. Part of the guide member is located in the U-shaped guide groove, and part of the guide member can be inserted into the stop slot. The second slider can move back and forth inside the second housing and drive the guide member to circulate within the U-shaped guide groove.

[0015] Preferably, the guide includes a first connecting part, a second connecting part, and a guide rod. The first connecting part and the second connecting part are set at an acute angle. One end of the first connecting part and the second connecting part are fixedly connected. The other end of the first connecting part is provided with a plug-in part. The guide rod is disposed on the second connecting part. The end of the guide rod is disposed in a U-shaped guide groove. The plug-in part can be inserted into the gear position groove. The U-shaped guide groove includes a shift channel and a reset channel. When the guide rod is located in the shift channel, the plug-in part of the guide is located in the gear position groove. When the guide rod is located in the reset channel, the plug-in part of the guide is disengaged from the gear position groove.

[0016] Preferably, the lower part of the second slider is a protrusion, and the second slider is installed in the first groove of the second housing through the protrusion and can move back and forth in the first groove; the protrusion is hollow, the guide is located in the protrusion, and the protrusion has a first opening and a second opening. The first opening is located on the side of the protrusion near the U-shaped guide groove, and the lower end of the guide rod on the guide passes through the first opening and is set in the U-shaped guide groove. The second opening is located on the side of the protrusion near the gear slot, and the insertion part of the guide can pass through the second opening and be inserted into the gear slot.

[0017] Preferably, the gear slot is inclined to the rear, and the inclination direction of the front and rear channels of the U-shaped guide groove is the same as the inclination direction of the gear slot.

[0018] Preferably, the second handrail also includes a limiting member, which is fixedly connected to the second housing, and the second slider is located between the limiting member and the second housing.

[0019] A chair, including a backrest adjustment mechanism as described above.

[0020] This utility model, by adopting the above technical solution, has the following beneficial effects:

[0021] In this invention, the first and second armrests are fixedly installed on the left and right sides of the chair seat. The first and second outer shells of the armrests are hinged to the backrest. The first and second sliders, which are movably connected to the backrest, are respectively movably disposed inside the first and second outer shells. By using a button to lock or unlock the position of the first slider relative to the first outer shell using a gas spring inside the first armrest, the user only needs to press the button to unlock the gas spring and then lean back against the backrest. The backrest drives the first and second sliders to move backward, and the lower end of the backrest rotates relative to the first and second armrests, thereby simultaneously adjusting the depth and tilt angle of the backrest. Releasing the button fixes the position of the backrest. The adjustment method is simple and reliable. Attached Figure Description

[0022] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute a limitation thereof.

[0023] Figure 1 This is a schematic diagram of the structure of this utility model;

[0024] Figure 2 This is a structural diagram of the first handrail;

[0025] Figure 3 for Figure 2 A schematic diagram of the structure after removing the first cover plate;

[0026] Figure 4 for Figure 3 A structural diagram showing the structure after removing the first mounting plate;

[0027] Figure 5 This is a structural schematic diagram of the slider, button, gas spring, and reset transmission device;

[0028] Figure 6 This is a structural diagram of the second handrail;

[0029] Figure 7 for Figure 6 A schematic diagram of the structure after removing the second cover plate;

[0030] Figure 8 for Figure 7 A schematic diagram of the structure after removing the limiting component;

[0031] Figure 9 This is a schematic diagram of the second outer shell;

[0032] Figure 10 This is a schematic diagram of the structure of the second slider and the guide component;

[0033] Figure 11 This is a schematic diagram of the second slider.

[0034] Figure 12 This is a structural schematic diagram of the guide component;

[0035] Figure 13 This is a schematic diagram of the backrest structure;

[0036] Figure 14 This is an exploded view of the backrest.

[0037] Figure label:

[0038] 1. Backrest; 11. Back frame; 111. Limiting shaft; 12. Connecting piece; 13. Second limiting groove; 131. Gear notch; 14. Lumbar support; 141. Protrusion; 15. Stop;

[0039] 3. First handrail; 31. First outer shell; 313. First limiting hole; 314. First through hole; 315. First mounting plate; 32. First slider; 321. First oval hole; 331. Cylinder; 332. Piston rod; 333. Swing block; 334. Transmission line; 335. Rotating block; 336. Rotating seat; 337. Connecting seat; 34. Button; 35. First cover plate;

[0040] 4. Second handrail; 41. Second outer shell; 411. First groove; 4113. Bottom wall of the first groove; 413. Second limiting hole; 414. Second through hole; 415. Second mounting plate; 42. Second slider; 421. Protrusion; 4211. First opening; 4212. Second opening; 4213. Second groove; 422. Second oval hole; 43. Guide member; 431. First connecting part; 4311. Insertion part; 432. Second connecting part; 433. Guide rod; 434. Rotating shaft; 44. U-shaped guide groove; 441. Gear shifting channel; 442. Reset channel; 443. Front channel; 444. Rear channel; 45. Limiting member; 46. Gear slot; 47. Second cover plate. Detailed Implementation

[0041] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0042] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0043] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more, unless otherwise expressly defined.

[0044] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0045] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0046] For clarity, in this invention, the side where the user sits is considered the front, and the opposite side is considered the back; the side closer to the center of the chair is considered the inside, and the opposite side is considered the outside.

[0047] like Figures 1 to 14 As shown, this utility model discloses a backrest adjustment mechanism, including: a backrest 1; a seat (not shown); a first armrest 3, including a first housing 31 and a first slider 32 and a gas spring installed inside the first housing 31, the gas spring being connected to the first slider 32 and capable of driving the first slider 32 to move back and forth, and a button 34 for triggering the gas spring being provided on the side wall of the first housing 31; a second armrest 4, including a second housing 41 and a second slider 42 installed inside the second housing 41, the second slider 42 being capable of sliding back and forth inside the second housing 41; the first armrest 3 and the second armrest 4 are respectively fixedly connected to the left and right sides of the seat, the rear ends of the first housing 31 and the second housing 41 are respectively hinged to the left and right sides of the backrest 1, and the rear ends of the first slider 32 and the second slider 42 are respectively movably connected to the left and right sides of the backrest 1.

[0048] In this invention, the first armrest 3 and the second armrest 4 are fixedly installed on the left and right sides of the seat. The first outer shell 31 of the first armrest 3 and the second outer shell 41 of the second armrest 4 are respectively hinged to the left and right sides of the backrest 1. The first slider 32 and the second slider 42, which are movably connected to the backrest 1, are respectively movably disposed inside the first outer shell 31 and the second outer shell 41. The position of the first slider 32 relative to the first outer shell 31 is locked or unlocked by the gas spring inside the first armrest 3 through the button 34. Thus, when the backrest 1 needs to be adjusted, the user only needs to press the button to unlock the gas spring, and then lean back against the backrest 1. The backrest 1 drives the first slider 32 and the second slider 42 to move backward, and the lower end of the backrest 1 rotates relative to the first armrest 3 and the second armrest 4, thereby simultaneously adjusting the depth and tilt angle of the backrest 1. Releasing the button 34 can fix the position of the backrest 1.

[0049] In this plan, such as Figure 1 , Figure 2 and Figure 6 As shown, the hinge point between the first slider 32 and the backrest 1 is located above the connection point between the first housing 31 and the backrest 1, and the hinge point between the second slider 42 and the backrest 1 is located above the connection point between the second housing 41 and the backrest 1.

[0050] like Figure 2 and Figure 8 As shown, the inner wall of the first outer shell 31 is provided with a first limiting hole 313. The connecting part between the rear end of the first slider 32 and the backrest 1 is limited in the first limiting hole 313 and can move back and forth along the first limiting hole 313. The outer wall of the first outer shell 31 is provided with a first through hole 314, which can expose the connecting part between the rear end of the first slider 32 and the backrest 1. The first outer shell 31 is provided with a first mounting plate 315 for covering the first through hole 314. The inner wall of the second outer shell 41 is provided with a second limiting hole 413. The limiting part between the rear end of the second slider 42 and the backrest is limited in the second limiting hole 413 and can move back and forth along the second limiting hole 413. The outer wall of the second outer shell 41 is provided with a second through hole 414, which can expose the connecting part between the rear end of the second slider 42 and the backrest. The second outer shell 41 is provided with a second mounting plate 415 for covering the second through hole 414. In this invention, the backrest 1 has two protruding limiting shafts 111. The two limiting shafts 111 extend into the first limiting hole 313 and the second limiting hole 413 respectively and can move back and forth along the first limiting hole 313 and the second limiting hole 413. The rear end of the first slider 32 has a longitudinally arranged first oblong hole 321, and the rear end of the second slider 42 has a longitudinally arranged second oblong hole 422. The two limiting shafts 111 of the backrest 1 are respectively limited and installed in the first oblong hole 321 and the second oblong hole 422 by limiting rods. Thus, when the backrest 1 drives the first slider 32 and the second slider 42 to move back and forth, the limiting shafts 111 can move back and forth along the first limiting hole 313 and the second limiting hole 413. The lower end of the backrest 1 rotates relative to the first armrest 3 and the second armrest 4. The backrest 1 can be appropriately displaced relative to the first slider 32 and the second slider 42 by the limiting rods provided in the first oblong hole 321 and the second oblong hole 422, thereby preventing the backrest 1 from jamming.

[0051] The structure of the first handrail 3 is as follows: Figures 2 to 5As shown. A third through hole is provided on the left or right side wall of the first outer casing 31, and the button 34 is installed at the third through hole; the gas spring includes a cylinder 331, a piston, a piston rod 332, an unlocking block, a connecting seat 337, and a swing block 333. The cylinder 331 is fixedly disposed inside the first outer casing 31, and the piston is movably disposed inside the cylinder 331. One end of the piston rod 332 is connected to the piston, and the other end of the piston rod 332 is connected to the connecting seat 337. The connecting seat 337 is connected to the first slider 32, and a swing block groove is provided on the connecting seat 337. The unlocking block is movably disposed inside the piston rod 332 and extends from the end of the piston rod 332 away from the piston. The swing block 333... One end is placed in the groove of the swing block and hinged to the connecting seat 337. The swing block 333 swings to drive the unlocking block to unlock or lock the gas spring. The first housing 31 is also provided with a transmission line 334, a rotating block 335 and a rotating seat 336. The rotating seat 336 is installed at the third through hole. The rotating block 335 is hinged to the rotating seat 336. The transmission line 334 connects the rotating block 335 and the swing block 333. The button 34 passes through the third through hole and the rotating seat 336 and is connected to the rotating block 335. The external force acting on the button 34 is transmitted to the swing block 333 through the rotating block 335 and the transmission line 334. The swing block 333 swings to unlock the unlocking block and realize the unlocking of the gas spring.

[0052] The transmission line 334 includes a sleeve and a core wire passing through the sleeve. The sleeve is a flexible but non-stretchable spiral metal tube, and the core wire is a steel wire rope. The two ends of the steel wire rope are connected to the rotating block 335 and the swing block 333 respectively through ball heads.

[0053] An elastic element for resetting the press 34 is provided between the press 34 and the rotating seat 336. An elastic element for resetting the rotating block 335 is provided between the rotating seat 336 and the rotating block 335; and / or, an elastic element for resetting is provided between the swing block 333 and the piston rod 332. Thus, pressing the press 34 causes the rotating block 335 to rotate, which in turn causes the transmission line 334 to pull the swing block 333. The swing block 333 swings to unlock the gas spring, releasing the press 34 and resetting it. The rotating block 335 is reset under the action of the elastic element, and / or the swing block 333 is reset under the action of the elastic element. The unlocking block is no longer compressed, the gas spring is locked, the length of the piston rod 332 no longer changes, and the backrest 1 stops at this position.

[0054] In this design, the positioning structure between the second outer shell 41 and the second slider 42 is as follows: a first groove 411 is provided inside the second outer shell 41, and multiple positioning slots 46 are provided on the left or right side wall of the first groove 411. A loop-shaped guide groove 44 is provided on the bottom wall 4113 of the first groove 411. A guide member 43 is provided inside the second outer shell 41. The guide member 43 is hinged to the second slider 42. Part of the guide member 43 is located in the loop-shaped guide groove 44, and part of the guide member 43 can be inserted into the positioning slots 46. The second slider 42 can move back and forth inside the second outer shell 41 and drive the guide member 43 to move cyclically in the loop-shaped guide groove 44.

[0055] In this way, when the second slider 42 moves backward, it drives the guide 43 to switch gears in the gear slot 46. When the last gear needs to be reset, simply lean back against the backrest 1 to disengage the guide 43 from the gear slot 46. Then, without leaning against the backrest 1, the guide 43 can move cyclically in the loop guide groove 44 to the first gear, completing the gear reset. The gear adjustment and gear reset structure is simplified, and the adjustment method is simple and reliable.

[0056] The structure of the second handrail is as follows: Figures 6 to 12 As shown. Figure 12 As shown, the guide member 43 includes a first connecting part 431, a second connecting part 432, and a guide rod 433. The first connecting part 431 and the second connecting part 432 are set at an acute angle. One end of the first connecting part 431 is fixedly connected to the second connecting part 432. The connection between the first connecting part 431 and the second connecting part 432 is hinged to the second slider 42 through a rotating shaft 434. The other end of the first connecting part 431 is provided with a plug-in part 4311, and the guide rod 433 is disposed on the second connecting part 432. The end of the guide rod 433 is disposed in the U-shaped guide groove 44, and the plug-in part 4311 can be inserted into the gear slot 46.

[0057] The spiral guide groove 44 includes a shift channel 441 and a reset channel 442. When the guide rod 433 is located in the shift channel 441, the insertion part 4311 of the guide member 43 is located in the gear position groove 46; when the guide rod 433 is located in the reset channel 442, the insertion part 4311 of the guide member 43 is dislodged from the gear position groove 46.

[0058] like Figure 9 As shown, the gear slot 46 is inclined to the rear, and the inclination direction of the front channel 443 and the rear channel 444 of the U-shaped guide groove 44 is the same as the inclination direction of the gear slot 46.

[0059] When the insertion part 4311 of the guide member 43 is located in the gear position slot 46, the guide rod 433 is located in the gear shift channel 441. After unlocking the gas spring, leaning back against the backrest 1 causes the first slider 32 and the second slider 42 to move backward, thereby causing the guide member 43 to move backward to achieve gear shifting. When the insertion part 4311 is located in the last gear position slot 46, the guide rod 433 is located at the rear end of the gear shift channel 441. Continuing to lean back against the backrest 1, the guide rod 433 moves along the rear channel 444 to... At the upper end of the reset channel 442, the insertion part 4311 disengages from the gear position groove 46. At this time, the external force applied to the backrest 1 is reduced, and the gas spring applies a restoring force to the first slider 32, causing the backrest 1 to return forward. This causes the second slider 42 to move forward quickly to the front end of the reset channel 442. The guide rod 433 moves to the front end of the reset channel 442 and continues to move forward to the front end of the shift channel 441. The insertion part 4311 is inserted into the gear position groove 46 at the frontmost end, completing the gear position reset.

[0060] like Figure 10 and Figure 11 As shown, the lower part of the second slider 42 is a protrusion 421. The second slider 42 is mounted in the first groove 411 of the second housing 41 through the protrusion 421 and can move back and forth within the first groove 411. The width of the protrusion 421 is approximately the same as the width of the first groove 411. Thus, when force is applied to the second slider 42, the second slider 42 can only move back and forth along the first groove 411, preventing the second slider 42 from wobbling and causing the insertion part 4311 of the guide member 43 to disengage from the gear slot 46 during gear shifting, making the adjustment more reliable.

[0061] The protrusion 421 is hollow, and the guide member 43 is located inside the protrusion 421. The protrusion 421 has a first opening 4211 and a second opening 4212. The first opening 4211 is located on the side of the protrusion 421 near the U-shaped guide groove 44. The lower end of the guide rod 433 on the guide member 43 passes through the first opening 4211 and is placed in the U-shaped guide groove 44. The other end of the guide rod 433 abuts against the guide member 43. In other embodiments, the protrusion 421 also has a second groove 4213 opposite to the first opening 4211, and the other end of the guide rod 433 is placed in the second groove 4213. In this way, when the guide rod 43 moves along the front channel 443 and the rear channel 444 of the U-shaped guide groove 44, the guide rod 43 can be limited to move within the first opening 4211. The second opening 4212 is located on the side of the protrusion 421 near the gear slot 46, and the insertion part 4311 of the guide 43 can pass through the second opening 4212 and be inserted into the gear slot 46.

[0062] like Figure 8As shown, the second handrail 4 also includes a limiting member 45, which is fixedly connected to the second outer shell 41. The second slider 42 is located between the limiting member 45 and the second outer shell 41, thereby preventing the second slider 42 from coming out of the first groove 411.

[0063] like Figure 13 and Figure 14 As shown, the backrest 1 includes a back frame 11 and a connector 12. The connector 12 is shaped like a "human," with its upper end connected to the upper connecting edge of the back frame 11 and its lower end connected to the left and right connecting edges of the back frame 11. The back frame 11 and the connector 12 are integrally formed. To support the user's lower back, the backrest 1 also includes a lumbar support 14. A second limiting groove 13 is provided at the lower part of the left and right connecting edges of the back frame 11. Multiple vertically arranged stop recesses 131 are provided on the inner wall of the limiting groove 13. The left and right ends of the lumbar support 14 are respectively positioned within the limiting groove 13 in a vertically movable manner. The lumbar support 14 has protrusions 141 that can fit into the stop recesses 131. This allows the user to move the lumbar support 14 up and down according to their needs. A stop 15 is installed at the limiting groove 13 to prevent the lumbar support 14 from slipping out of the limiting groove 13. The side wall where the gear position notch 131 is located is thin-walled, which can further increase the elasticity of the side wall where the gear position notch 131 is located, making it easier for the lumbar support 14 to adjust the gear position up and down within the limiting groove 13.

[0064] Of course, a headrest can also be provided on the backrest 1. The headrest is installed on the backrest 1 via a support member. The headrest can be fixed to the upper end of the support member, or it can be rotatably installed on the support member, or it can be installed on the support member in a way that allows it to move up and down.

[0065] This utility model also discloses a chair, including a backrest adjustment mechanism as described above.

[0066] All features described in the specification, appended claims and drawings, whether individually or in any combination thereof, are essential features of this utility model.

[0067] The technical solutions described in this utility model also include any one or more specific features, structures, materials or characteristics described above, formed individually or in combination.

[0068] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, alterations, deletions of some features, additions of features, or recombinations of features to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the innovative principles of the present invention shall still fall within the scope of the technical solutions of the present invention.

Claims

1. A backrest adjustment mechanism, characterized in that, include: Backrest (1); Seat; The first handrail (3) includes a first housing (31) and a first slider (32) and a gas spring installed inside the first housing (31). The gas spring is connected to the first slider (32) and can drive the first slider (32) to move back and forth. The side wall of the first housing (31) is provided with a button (34) for triggering the gas spring. The second handrail (4) includes a second housing (41) and a second slider (42) installed inside the second housing (41), the second slider (42) being able to slide back and forth inside the second housing (41); The first armrest (3) and the second armrest (4) are fixedly connected to the left and right sides of the seat, respectively. The rear end of the first shell (31) and the rear end of the second shell (41) are hinged to the left and right sides of the backrest (1), respectively. The rear end of the first slider (32) and the rear end of the second slider (42) are movably connected to the left and right sides of the backrest (1), respectively.

2. The backrest adjustment mechanism according to claim 1, characterized in that, The inner wall of the first outer shell (31) is provided with a first limiting hole (313), and the connecting part between the rear end of the first slider (32) and the backrest (1) is limited in the first limiting hole (313) and can move back and forth along the first limiting hole (313); the inner wall of the second outer shell (41) is provided with a second limiting hole (413), and the limiting part between the rear end of the second slider (42) and the backrest is limited in the second limiting hole (413) and can move back and forth along the second limiting hole (413).

3. The backrest adjustment mechanism according to claim 1, characterized in that, A third through hole is provided on the left or right side wall of the first outer casing (31), and the mounting piece (34) is installed at the third through hole; the end of the piston rod (332) on the gas spring away from the cylinder (331) is connected to a connecting seat (337), the connecting seat (337) is connected to the first slider (32), the connecting seat (337) is provided with a swing block groove, and a swing block (333) is hinged in the swing block groove. When the swing block (333) swings to contact the piston rod (332), it can unlock the gas spring; a transmission line is also provided inside the first outer casing (31). 334), rotating block (335) and rotating seat (336), rotating seat (336) is installed at the third through hole, rotating block (335) is hinged to rotating seat (336), transmission line (334) connects rotating block (335) and swing block (333), pressing piece (34) passes through the third through hole and rotating seat (336) and is connected to rotating block (335), external force acting on pressing piece (34) is transmitted to swing block (333) through rotating block (335) and transmission line (334) to drive swing block (333) to swing.

4. The backrest adjustment mechanism according to claim 3, characterized in that, An elastic element for resetting the press (34) is provided between the press (34) and the rotating seat (336); An elastic element for resetting the rotating block (335) is provided between the rotating seat (336) and the rotating block (335), and / or an elastic element for resetting the swing block (333) is provided between the swing block (333) and the piston rod (332).

5. A backrest adjustment mechanism according to claim 1, characterized in that, The second slider (42) is installed inside the second housing (41) through a gearing structure. The second housing (41) has a first groove (411) inside. Multiple gearing slots (46) are opened on the left or right side wall of the first groove (411). A spiral guide groove (44) is opened on the bottom wall (4113) of the first groove (411). A guide member (43) is provided inside the second housing (41). The guide member (43) is hinged to the second slider (42). Part of the guide member (43) is located in the spiral guide groove (44). Part of the guide member (43) can be inserted into the gearing slot (46). The second slider (42) can move back and forth inside the second housing (41) and drive the guide member (43) to move cyclically in the spiral guide groove (44).

6. A backrest adjustment mechanism according to claim 5, characterized in that, The guide member (43) includes a first connecting part (431), a second connecting part (432), and a guide rod (433). The first connecting part (431) and the second connecting part (432) are set at an acute angle. One end of the first connecting part (431) and the second connecting part (432) are fixedly connected. The other end of the first connecting part (431) is provided with a plug-in part (4311). The guide rod (433) is disposed on the second connecting part (432). The end of the guide rod (433) is set in a U-shape. Inside the guide groove (44), the insertion part (4311) can be inserted into the gear position groove (46); the guide groove (44) includes a shift channel (441) and a reset channel (442). When the guide rod (433) is located in the shift channel (441), the insertion part (4311) of the guide member (43) is located in the gear position groove (46). When the guide rod (433) is located in the reset channel (442), the insertion part (4311) of the guide member (43) is dislodged from the gear position groove (46).

7. A backrest adjustment mechanism according to claim 5, characterized in that, The lower part of the second slider (42) is a protrusion (421). The second slider (42) is installed in the first groove (411) of the second outer shell (41) through the protrusion (421) and can move back and forth in the first groove (411). The protrusion (421) is hollow, and the guide (43) is located in the protrusion (421). The protrusion (421) has a first opening (4211) and a second opening (4212). The first opening (4211) is located on the side of the protrusion (421) near the U-shaped guide groove (44). (43) The lower end of the upper guide rod (433) passes through the first opening (4211) and is set in the loop guide groove (44). The second opening (4212) is located on the side of the protrusion (421) near the gear slot (46). The insertion part (4311) of the guide (43) can pass through the second opening (4212) and be inserted into the gear slot (46). The gear slot (46) is set at an angle to the rear. The inclination direction of the front channel (443) and the rear channel (444) of the loop guide groove (44) is the same as the inclination direction of the gear slot (46).

8. A backrest adjustment mechanism according to claim 5, characterized in that, The gear slot (46) is inclined to the rear, and the inclination direction of the front channel (443) and the rear channel (444) of the spiral guide (44) is the same as the inclination direction of the gear slot (46).

9. A backrest adjustment mechanism according to claim 1, characterized in that, The second handrail (4) also includes a limiting member (45), which is fixedly connected to the second outer shell (41), and the second slider (42) is located between the limiting member (45) and the second outer shell (41).

10. A chair, characterized in that, Includes a backrest adjustment mechanism as described in any one of claims 1-9.

Images