Backrest angle adjustment locking structure

Abstract

The utility model relates to the field of office chair discloses a locking structure of backrest angle adjustment, including chair back, the chair back rotatable setting in the rear side of seat pad, the rear side of seat pad is fixed with two mounting seat, two mounting seat between fixed with connecting shaft, the outer wall of connecting shaft is fixed with two gear, the bottom of chair back is fixed with connecting seat, the connecting seat rotatable setting in connecting shaft outer wall, the front side of chair back is equipped with accommodating groove, the inside bottom of accommodating groove is equipped with through -hole, the through -hole extends to connecting seat, the through -hole corresponds with gear, the inner wall of accommodating groove is connected with sliding block slidingly, in the utility model, through the cooperation of gear, sliding block, locating plate and spring, the adjusting angle of chair back can be limited, ensure that the angle between chair back and seat pad keeps constant in the set range, effectively prevent the angle deviation of chair back because of the collision of external force.

Description

Technical Field

[0001] This utility model relates to the technical field of office chairs, specifically a locking structure for adjusting the backrest angle. Background Technology

[0002] In a narrow sense, an office chair refers to a chair with a backrest used for desk work in a seated position. In a broader sense, it refers to all chairs used in offices, including staff chairs, conference chairs, visitor chairs, training chairs, etc. When adjusting the backrest of an office chair, it is difficult to maintain a consistent angle without an angle limiting device.

[0003] Chinese patent CN215820314U discloses a locking mechanism for an office chair backrest, comprising a base, a first fixing block, and a second fixing block. Four movable wheels are fixedly installed on the bottom of the base and evenly distributed around its perimeter. Two main armrests are fixedly installed on the outer wall of the top of the base and distributed on both sides of the top of the base. A screw is threaded onto the inner walls of both sides of the base, and the base is movably connected to the first fixing block via the screw.

[0004] In the above solution, the cylinder inside the slider is controlled to extend it. The extended cylinder passes through the limiting hole on the second connecting rod, thus restricting the chair back. This results in the following disadvantages: the locking is triggered only by the cylinder, but the cylinder requires constant pressure air supply. If there is a power outage or air outage, it cannot effectively ensure that the angle remains constant within the set range. Utility Model Content

[0005] The purpose of this invention is to provide a locking structure for adjusting the backrest angle, in order to solve the problem that locking is triggered by a cylinder, but the cylinder requires constant pressure air supply, and if there is a power outage or air outage, the angle cannot be effectively kept constant within the set range.

[0006] To achieve the above-mentioned utility model objectives, the present utility model adopts the following technical solution: a locking structure for adjusting the backrest angle, including a chair back, the chair back being rotatably disposed on the rear side of the seat cushion, two mounting seats being fixed on the rear side of the seat cushion, a connecting shaft being fixed between the two mounting seats, two gears being fixed on the outer wall of the connecting shaft, a connecting seat being fixed on the bottom surface of the chair back, the connecting seat being rotatably disposed on the outer wall of the connecting shaft, a receiving groove being provided on the front side of the chair back, a through hole being provided on the inner bottom surface of the receiving groove, the through hole extending into the connecting seat, the through hole corresponding to the gears, a sliding block being slidably connected to the inner wall of the receiving groove, a positioning plate being fixed on the bottom surface of the sliding block, the positioning plate being inserted into the through hole, the bottom end of the positioning plate engaging with the gears, and two springs being fixed on the top surface of the sliding block, the top ends of the springs being fixed to the inner top surface of the receiving groove.

[0007] Preferably, a positioning groove is provided on the left side of the sliding block, and an L-shaped hole is provided on the front side of the chair back. An L-shaped rod is slidably connected to the inner wall of the L-shaped hole, and one end of the L-shaped rod is inserted into the positioning groove.

[0008] Preferably, an elastic plate is fixed to the rear side of the chair back, and the other end of the elastic plate is fixed to the bottom surface of the seat cushion.

[0009] Preferably, the inner wall of the receiving groove is provided with limiting grooves on both the left and right sides, and the sliding block is fixed with limiting posts on both the left and right sides, and the limiting posts are slidably connected in the limiting grooves.

[0010] Preferably, a mounting plate is fixed to the front side of the sliding block, a bracket is fixed to the mounting plate, and the outer wall of the bracket is covered with an elastic mesh.

[0011] Preferably, armrests are fixed on both the left and right sides of the seat cushion, and a rubber pad is fixed on the top surface of the armrests.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] 1. Through the coordinated action of gears, sliding blocks, positioning plates, and springs, the adjustment angle of the chair back can be limited, ensuring that the angle between the chair back and the seat cushion remains constant within the set range. This effectively prevents the angle of the chair back from deviating due to external impacts, ensuring the structural stability and safety of the chair back during use, thereby improving overall performance. 2. Through the coordinated action of the L-shaped rod and L-shaped hole, the sliding block can be auxiliaryly limited and fixed, making it more stable after angle adjustment and effectively preventing it from wobbling due to external impacts.

[0014] Second, the elastic plate can limit the tilt angle of the chair back or provide a rebound force, for example, to assist in resetting when adjusting the chair back. Simultaneously, once the angle between the chair back and the seat cushion is fixed, it enhances the overall structural stability and prevents excessive swaying or deformation of the chair back. Through the synergistic action of the limiting post and the limiting groove, the sliding block can slide along a predetermined track, making the sliding block more stable during movement and ensuring that the bottom end of the positioning plate accurately meshes with the gear, thereby improving the stability of the sliding block.

[0015] Third, the elastic mesh provides dynamic support for the user's lower back through its flexibility and breathability, adapting to the lumbar curve under different sitting postures. It can slightly deform with body movements, relieving local pressure, improving comfort during prolonged sitting, and avoiding the pressure caused by hard support. The soft material of the rubber pad increases the comfort of the user's elbows and reduces discomfort from prolonged contact, thereby improving the practicality of the rubber pad. Attached Figure Description

[0016] Figure 1 This is a three-dimensional schematic diagram of an embodiment.

[0017] Figure 2 This is a breakdown diagram of an embodiment.

[0018] Figure 3 This is a schematic diagram showing the disassembled sliding block and positioning plate in an embodiment.

[0019] Figure 4 For the example Figure 2 Enlarged diagram of point A in the middle.

[0020] In the diagram: 1. Chair back; 2. Seat cushion; 201. Mounting base; 3. Gear; 4. Connecting base; 5. Receiving groove; 6. Through hole; 7. Sliding block; 8. Positioning plate; 9. Spring; 10. Positioning groove; 11. L-shaped hole; 12. L-shaped rod; 13. Elastic plate; 14. Limiting groove; 15. Limiting post; 16. Mounting plate; 17. Bracket; 18. Elastic mesh; 19. Armrest; 20. Rubber pad. Detailed Implementation

[0021] The preferred embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0022] like Figures 1-4 As shown, a locking structure for adjusting the backrest angle includes a chair back 1, which is rotatably mounted on the rear side of a seat cushion 2. Two mounting seats 201 are fixed to the rear side of the seat cushion 2, and a connecting shaft is fixed between the two mounting seats 201. Two gears 3 are fixed to the outer wall of the connecting shaft. A connecting seat 4 is fixed to the bottom surface of the chair back 1 and is rotatably mounted on the outer wall of the connecting shaft. A receiving groove 5 is provided on the front side of the chair back 1, and a through hole 6 is provided on the inner bottom surface of the receiving groove 5, extending into the connecting seat 4. The through hole 6 connects with... Corresponding to gear 3, a sliding block 7 is slidably connected to the inner wall of the receiving groove 5. A positioning plate 8 is fixed to the bottom surface of the sliding block 7. The positioning plate 8 is inserted into the through hole 6. The bottom end of the positioning plate 8 meshes with gear 3. Two springs 9 are fixed to the top surface of the sliding block 7. The top end of the springs 9 is fixed to the inner top surface of the receiving groove 5. A positioning groove 10 is opened on the left side of the sliding block 7. An L-shaped hole 11 is opened on the front side of the chair back 1. An L-shaped rod 12 is slidably connected to the inner wall of the L-shaped hole 11. One end of the L-shaped rod 12 is inserted into the positioning groove 10.

[0023] In use, when the user needs to adjust the angle of the backrest 1, external force can be applied to the mounting plate 16 and the bracket 17 to make them move upward synchronously. This operation will drive the sliding block 7 to move the positioning plate 8 upward, and at the same time compress the spring 9, causing the bottom end of the positioning plate 8 to disengage from the gear 3. At this time, the relative angle between the backrest 1 and the seat cushion 2 can be steplessly adjusted based on the rotational freedom of the connecting seat 4 on the outer wall of the connecting shaft of the mounting seat 201.

[0024] Once the backrest 1 is adjusted to the target angle, the external force is removed, and the spring 9 releases its elastic potential energy to push the sliding block 7 to reset. Then, the bottom end of the positioning plate 8 is re-engaged with the gear 3 through the downward displacement of the positioning plate 8, thereby completing the self-locking of the backrest 1 angle. In addition, the user can insert the end of the L-shaped rod 12 into the positioning groove 10 to form a mechanical interlocking structure, which further enhances the locking reliability and effectively prevents the backrest 1 angle deviation caused by the accidental displacement of the sliding block 7, ensuring adjustment accuracy and safety of use.

[0025] Through the coordinated action of gear 3, sliding block 7, positioning plate 8, and spring 9, the adjustment angle of the chair back 1 can be limited, ensuring that the angle between the chair back 1 and the seat cushion 2 remains constant within the set range. This effectively prevents the angle of the chair back 1 from deviating due to external impacts, ensuring the structural stability and safety of the chair back 1 during use, thereby improving overall performance. Through the coordinated action of L-shaped rod 12 and L-shaped hole 11, the sliding block 7 can be auxiliaryly limited and fixed, making it more stable after angle adjustment and effectively preventing it from shaking due to external impacts.

[0026] like Figures 1-4 As shown, an elastic plate 13 is fixed to the rear side of the backrest 1, and the other end of the elastic plate 13 is fixed to the bottom surface of the seat cushion 2. Limiting grooves 14 are opened on both the left and right sides of the inner wall of the receiving groove 5. Limiting posts 15 are fixed on both the left and right sides of the sliding block 7. The limiting posts 15 are slidably connected in the limiting grooves 14. An installation plate 16 is fixed to the front side of the sliding block 7. A bracket 17 is fixed on the installation plate 16. The outer wall of the bracket 17 is covered with an elastic net 18. Armrests 19 are fixed on both the left and right sides of the seat cushion 2. A rubber pad 20 is fixed to the top surface of the armrest 19.

[0027] During use, the elastic plate 13 can limit the tilt angle of the chair back 1 or provide a rebound force, for example, to assist in resetting when adjusting the chair back 1. Simultaneously, after the angle between the chair back 1 and the seat cushion 2 is fixed, the overall structural stability is enhanced, preventing excessive swaying or deformation of the chair back 1. Through the synergistic action of the limiting post 15 and the limiting groove 14, the sliding block 7 can slide along a predetermined track, making the sliding block 7 more stable during movement and ensuring that the bottom end of the positioning plate 8 accurately engages with the gear 3, thereby improving the stability of the sliding block 7. The flexibility and breathability of the elastic mesh 18 provide dynamic support for the user's lower back, adapting to the lumbar curve under different sitting postures. It can slightly deform with body movements, relieving local pressure, improving comfort during prolonged sitting, and avoiding the pressure caused by hard supports. The soft material of the rubber pad 20 increases the comfort of the user's elbows, reducing discomfort from prolonged contact, thereby improving the practicality of the rubber pad 20.

[0028] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A locking structure for adjusting the backrest angle, comprising a backrest (1) rotatably disposed on the rear side of a seat cushion (2), characterized in that, Two mounting seats (201) are fixed to the rear side of the seat cushion (2), and a connecting shaft is fixed between the two mounting seats (201). Two gears (3) are fixed to the outer wall of the connecting shaft. A connecting seat (4) is fixed to the bottom surface of the backrest (1). The connecting seat (4) is rotatably mounted on the outer wall of the connecting shaft. A receiving groove (5) is opened on the front side of the backrest (1). A through hole (6) is opened on the bottom surface of the receiving groove (5). The through hole (6) extends into the connecting seat (4). The through hole (6) corresponds to the gear (3). A sliding block (7) is slidably connected to the inner wall of the receiving groove (5). A positioning plate (8) is fixed to the bottom surface of the sliding block (7). The positioning plate (8) is inserted into the through hole (6). The bottom end of the positioning plate (8) meshes with the gear (3). Two springs (9) are fixed to the top surface of the sliding block (7). The top end of the springs (9) is fixed to the top surface of the receiving groove (5).

2. The locking structure for adjusting the backrest angle according to claim 1, characterized in that: The sliding block (7) has a positioning groove (10) on its left side, and the backrest (1) has an L-shaped hole (11) on its front side. An L-shaped rod (12) is slidably connected to the inner wall of the L-shaped hole (11), and one end of the L-shaped rod (12) is inserted into the positioning groove (10).

3. The locking structure for adjusting the backrest angle according to claim 2, characterized in that: An elastic plate (13) is fixed to the rear side of the chair back (1), and the other end of the elastic plate (13) is fixed to the bottom surface of the seat cushion (2).

4. The locking structure for adjusting the backrest angle according to claim 3, characterized in that: The inner wall of the receiving groove (5) has limit grooves (14) on both the left and right sides, and the sliding block (7) has limit posts (15) fixed on both the left and right sides. The limit posts (15) are slidably connected in the limit grooves (14).

5. The locking structure for adjusting the backrest angle according to claim 4, characterized in that: A mounting plate (16) is fixed to the front side of the sliding block (7), and a bracket (17) is fixed on the mounting plate (16). The outer wall of the bracket (17) is covered with an elastic mesh (18).

6. The locking structure for adjusting the backrest angle according to claim 3, characterized in that: The seat cushion (2) is fixed with armrests (19) on both the left and right sides, and a rubber pad (20) is fixed on the top surface of the armrests (19).

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