Office chair with adjustable backrest

Abstract

The utility model discloses an office chair with an adjustable backrest, which comprises a supporting leg seat, a chair seat and a chair back, an adjustable bearing component is mounted on the supporting leg seat, the chair seat is fixed on the component, and the chair back is rotatably connected with the component through a back frame; the adjustable bearing assembly comprises a gear box, a ratchet wheel, ratchets and a sliding pin locking mechanism, the ratchet wheel is linked with the back frame, the ratchets and a sliding pin can achieve angle locking, the sliding pin is controlled by an operating rod, and an extension spring is arranged to provide meshing force; and an elastic recovery piece is arranged on one side of the assembly and is used for realizing automatic rebound of the backrest. The structure has the advantages of being stable in adjustment, reliable in locking, automatic in rebounding and convenient to operate, and the ergonomic performance and the use safety of the office chair are remarkably improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to office chair technical field, concretely is an office chair with adjustable backrest. BACKGROUND

[0002] With the popularization of office automation and ergonomics concept, the office chair not only serves as the basic furniture indispensable in daily work, but also its comfort and functionality increasingly become the important direction of product research and development. In particular, the office chair with adjustable backrest function has significant meaning in meeting the needs of different users' sitting posture and relieving long-term office fatigue.

[0003] In the prior art, the common adjustable backrest office chair usually adopts fixed angle tooth plate buckle structure, friction hinge adjustment structure or air pressure type jacking rod adjustment structure to realize the angle change of the backrest. For example, a typical structure is to set a friction pin shaft between the chair back and the base, and the user realizes the inclination of the backrest by the body strength, but due to the lack of effective locking mechanism, the adjustment angle is not accurate and is easy to rebound, which has safety hazards.

[0004] Another structure adopts the segmented adjustment mode of ratchet + toothed disc, although it can realize the segmented adjustment, but the structure is complex and inconvenient to operate, especially the backrest position after adjustment is easy to produce micro-motion under stress, which cannot be stably fixed. In addition, most of the structures lack automatic recovery function, the user needs to manually support the backrest, the operation is cumbersome, and long-term use is easy to cause structure wear and loose.

[0005] Therefore, the existing problems are researched and improved, and the office chair with adjustable backrest is provided to solve the existing problems, so as to solve the problems and improve the practical value through the technology. SUMMARY

[0006] The utility model aims at solving one of the technical problems existing in the prior art or related art.

[0007] The utility model provides an office chair with adjustable backrest, which comprises a supporting foot base, a chair seat and a chair back.

[0008] The top end of the support base is fixedly provided with an adjustable seat support assembly, the top surface of the assembly being used for fixedly mounting the seat. The surface of the backrest is fixedly connected with a back frame, one end of the back frame being rotatably connected with the adjustable seat support assembly, so that the backrest can be angularly adjusted relative to the seat. One side of the adjustable seat support assembly is fixedly provided with an elastic return member. The elastic return member comprises a fixed seat and an elastic sheet fixed to the surface of the fixed seat, one end of the elastic sheet penetrating through the fixed seat and abutting against the bottom surface of the back frame, for providing elastic force after the backrest is deflected, so as to realize the backrest resetting. The adjustable seat support assembly further comprises a gear box, a ratchet wheel and a ratchet. The ratchet wheel is rotatably mounted in the gear box, and both ends of the ratchet wheel are fixedly connected with the back frame, so as to realize the linkage of the backrest angle. The ratchet is also rotatably mounted in the gear box, and the surface of the ratchet is provided with a slide pin rod, the surface of the slide pin rod being connected with a tension spring, the other end of the spring being fixed to the outer wall of the gear box, so as to provide the meshing pre-tightening force of the slide pin. The middle part of the slide pin rod is provided with an operation rod, and the user can realize the locking and unlocking control by operating the rod. The structure realizes the multi-stage adjustable and automatic return function of the backrest angle, and has the advantages of compact structure, convenient adjustment and intuitive operation.

[0009] Preferably, the back frame is made of low-carbon steel material, which has high strength and moderate elasticity; and the structure of the back frame is L-shaped, which is used for flexibly connecting with the backrest, providing elastic support for the backrest and playing a shape stabilizing role.

[0010] Technical effect: By the L-shaped steel back frame, the strength of the backrest is enhanced and the impact feeling during use is alleviated.

[0011] Preferably, the elastic sheet is a high-elasticity metal member such as manganese steel sheet or carbon steel, which has excellent elastic performance, and one end of the elastic sheet is in contact with the bottom of the back frame, so as to realize the timely elastic return after deflection.

[0012] Technical effect: The backrest is automatically restored when the user relaxes, and the ergonomics experience is enhanced.

[0013] Further preferably, when the elastic sheet is in a natural state, the backrest and the seat form a vertical included angle, which is the initial state of the chair out of the factory, facilitating transportation and initial use.

[0014] Technical effect: The standard sitting angle is provided, the chair is convenient to stack and package, and the production consistency is improved.

[0015] Preferably, one end of the ratchet is provided with a barb tooth structure, which can be precisely meshed with the tooth groove structure on the surface of the ratchet wheel, for realizing the locking positioning after the angle adjustment of the backrest.

[0016] The meshing of the ratchet and the ratchet wheel is driven by the slide pin rod, and the slide pin is withdrawn to release the meshing, so that the backrest can be freely adjusted.

[0017] Technical effects: through the ratchet engagement, reliable locking chair back angle, prevent accidental tilt, improve the use of security.

[0018] Preferably, the tension spring is kept in a pre-tension state during installation, and the pre-tightening force is designed and calibrated to ensure that the slide pin rod is always in engagement with the ratchet when the operating lever is not operated.

[0019] Technical effects: realize the automatic maintenance state of backrest locking, without external force, improve the system stability.

[0020] Preferably, the gear box is an integral injection molding structure, and the inside of the box body is provided with a limiting hole and a guide rail groove for positioning and guiding the assembly direction and movement trajectory of the ratchet, the ratchet and the slide pin rod.

[0021] Technical effects: effectively reduce the assembly error and component swing, simplify the manufacturing and assembly process, improve the overall assembly precision and strength.

[0022] The beneficial effects obtained by the utility model are as follows:

[0023] 1. In the utility model, by setting the ratchet and ratchet engagement linkage mechanism, combined with the slide pin locking and spring pre-tightening control, ensure that the chair back can be stably positioned after adjustment, avoid accidental rebound or slip, significantly improve the safety and stability during use.

[0024] 2. In the utility model, by setting the elastic recovery member, the chair back can automatically rebound to the initial position after loosening, which meets the ergonomic principle, is convenient to operate, effectively improves the problem of inconvenient adjustment or manual reset of traditional office chairs, and enhances the user experience. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 It is a whole structure schematic view of an embodiment of the utility model;

[0026] Figure 2 It is a schematic view of the adjustable seat assembly and backrest connecting structure of an embodiment of the utility model;

[0027] Figure 3 It is a schematic view of the inside structure of the gear box of an embodiment of the utility model;

[0028] Figure 4 It is a schematic view of the ratchet and ratchet structure of an embodiment of the utility model;

[0029] Figure 5 It is a schematic view of the elastic recovery member structure of an embodiment of the utility model.

[0030] REFERENCE SIGNS:

[0031] 100, leg support; 110, seat; 120, backrest; 121, back frame;

[0032] 200, adjustable seat assembly; 210, gear box; 220, ratchet; 230, ratchet teeth; 231, sliding pin rod; 232, operating rod; 233, tension spring;

[0033] 300, elastic recovery device; 310, fixed seat; 320, elastic sheet. DETAILED DESCRIPTION

[0034] To make the purpose, technical scheme and advantages of the present application clearer and more comprehensible, the present application will be further described in detail below with reference to specific embodiments and drawings. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0035] It is understood that the above description is only exemplary and is not intended to limit the scope of the present application.

[0036] The drawings will be described below. Figures 1-5 Some embodiments of the present application provide an office chair with an adjustable backrest.

[0037] Embodiment one: office chair with gear-ratchet linkage locking structure

[0038] The present embodiment discloses an office chair with an adjustable backrest, comprising a leg support 100, a seat 110 and a backrest 120.

[0039] The top end of the leg support 100 is provided with an adjustable seat assembly 200, which is used to provide the core structure support for backrest angle adjustment; the seat 110 is fixedly installed on the top surface of the adjustable seat assembly 200 to realize stable bearing; the backrest 120 is connected with a back frame 121, one end of which is rotatably installed on the side wall or surface of the adjustable seat assembly 200 through a rotating connecting piece, so as to allow the backrest to change the angle of elevation.

[0040] On one side of the adjustable seat assembly 200, an elastic recovery device 300 is provided, which is composed of a fixed seat 310 and an elastic sheet 320 fixed thereon, one end of the elastic sheet 320 penetrating through the fixed seat 310 directly abuts against the bottom surface of the back frame 121, and automatically pushes the back frame forward after the user releases the operation, realizing the elastic recovery of the backrest position. Details are shown in Figure 2 .

[0041] The internal structure of the adjustable seat assembly 200 is as follows:

[0042] The gear box 210 is used to accommodate the adjusting mechanism;

[0043] The ratchet wheel 220 is rotatably installed inside the gear box 210, and both ends thereof are fixedly connected to the surface of the back frame 121 by means of screws or clamping grooves, so as to ensure the consistency of rotation; the ratchet gear 230 is also rotatably installed inside the gear box 210, and a slide pin rod 231 is arranged on the surface of the ratchet gear 230, which is in nested sliding fit and can move axially inward and outward; the slide pin rod 231 is connected with a tension spring 233, and the other end of the tension spring 233 is fixed to the shell of the gear box 210, so as to provide a continuous pre-tightening force; the middle part of the slide pin rod is connected with an operating rod 232, which is located on the side of the seat, and the user can realize the exit of the slide pin rod by pulling it upward, so as to release the ratchet-wheel-ratchet-gear locking and realize the free adjustment of the back frame.

[0044] The back frame 121 is formed by bending an L-shaped section steel plate, and is made of low-carbon steel, which has high structural strength and flexible buffering characteristics, so as to effectively improve the chair back supporting feeling and rebounding hand feeling. The elastic sheet 320 is made of high-elasticity silicon-manganese steel or carbon steel compression spring sheet, and is installed in the fixed seat 310, which has strong fatigue resistance. The backrest is kept perpendicular to the seat in the state that the elastic sheet is not stressed, that is, the original factory state is set to be an angle of 90°, so as to facilitate storage, transportation and initial installation and use.

[0045] The ratchet gear 230 is fixed to the gear box 210 through a rotating shaft, and the end portion thereof is provided with a barb structure, which can be precisely engaged with the tooth surface of the ratchet wheel 220, so as to achieve the angle position locking function. The tension spring 233 is in a pre-tightening state when it is initially installed, and can exert sufficient return force, so as to keep the slide pin rod 231 automatically embedded in the ratchet gear 230 when the user does not operate, and realize automatic locking. The gear box 210 is integrally formed by engineering plastic, and the inner wall of the box body is provided with limiting holes and guide rail grooves, which are respectively used for the directional installation and movement guidance of the ratchet wheel, the ratchet gear and the slide pin rod and other components, so as to facilitate assembly and have high reliability.

[0046] Specifically, the ratchet gear 230 is rotatably installed on the inner side of the gear box 210, and the surface thereof is provided with a slide pin rod 231, the surface of the slide pin rod 231 is connected with a tension spring 233, and the other end of the tension spring 233 is fixed to the surface of the gear box 210; the surface of the slide pin rod 231 is movably connected with an operating rod 232.

[0047] The ratchet gear 230 is rotatably installed on the inner side of the gear box 210, and one end thereof is in abutment engagement with the surface of the ratchet wheel 220, and the end portion of the ratchet gear 230 is engaged with the ratchet structure on the surface of the ratchet wheel 220, so as to realize the rotational locking of the back frame 121.

[0048] The gear box 210 is an integral injection molding structure, and the inside thereof is provided with limiting hole positions and guide rail grooves, which are used for limiting and guiding the movement paths of the ratchet wheel 220, the ratchet gear 230 and the slide pin rod 231.

[0049] Embodiment two: improved adjustable backrest office chair with buffering device

[0050] The embodiment is improved on the basis of embodiment one, and the difference lies in that:

[0051] A layer of high-density rubber cushion is arranged between the back frame 121 and the elastic sheet 320, which is used to absorb the impact force generated in the process of adjusting the backrest, and improve the comfort; at the same time, the operating rod 232 is arranged at the right side of the seat 110, and the gesture design can realize the single-handed easy unlocking of the backrest angle.

[0052] In addition, in the structure of the elastic return member 300, the elastic sheet 320 is replaced by a “helical torsion spring assembly”, one end of which is connected to the back frame 121, and the other end is fixed in the internal convolution groove of the fixed seat 310, and the automatic righting function of the backrest is realized through the pre-tightening torque, which is suitable for the scene of large-angle free adjustment such as high-back executive chair.

[0053] In the description of the specification, the description of the terms "one embodiment", "some embodiments", "a specific embodiment" and the like means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are contained in at least one embodiment or example of the utility model. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0054] Although the embodiments of the utility model have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and purposes of the utility model, and the scope of the utility model is defined by the claims and their equivalents.

Claims

1. An office chair with an adjustable backrest comprising a footrest base (100), a seat (110) and a backrest (120), characterized in that: The top end of the supporting leg base (100) is fixedly provided with an adjustable seat support assembly (200), and the seat (110) is fixed to the top surface of the adjustable seat support assembly (200); the surface of the backrest (120) is fixedly connected with a back frame (121), and one end of the back frame (121) is rotatably installed on the surface of the adjustable seat support assembly (200); one side of the adjustable seat support assembly (200) is fixedly provided with an elastic recovery device (300); The elastic recovery device (300) comprises a fixed seat (310) and elastic sheets (320) fixed to the surface of the fixed seat (310), one end of the elastic sheet (320) penetrates through the fixed seat (310) and abuts against the bottom surface of the back frame (121) to elastically recover the deflection of the back frame (121); the adjustable seat support assembly (200) comprises a gear box (210), a ratchet wheel (220) and a ratchet (230), the ratchet wheel (220) is rotatably installed on the inner side of the gear box (210), and both ends are fixedly connected with the surface of the back frame (121); the ratchet (230) is rotatably installed on the inner side of the gear box (210), and the surface thereof is provided with a sliding pin rod (231), the surface of the sliding pin rod (231) is connected with a tension spring (233), and the other end of the tension spring (233) is fixed to the surface of the gear box (210); the surface of the sliding pin rod (231) is movably connected with an operating rod (232).

2. An adjustable back office chair according to claim 1, characterized in that: The back frame (121) is a low-carbon steel material member, which is used for the flexible connection between the ratchet wheel (220) and the surface of the backrest (120) to provide elastic support effect for the backrest (120), and the back frame (121) is in L shape.

3. An adjustable back office chair according to claim 1, characterized in that: The elastic sheet (320) is an elastic material member, and one end thereof abuts against the bottom surface of the back frame (121) to recover the deflection of the back frame (121).

4. The adjustable-back office chair of claim 1, wherein: In the original state, the backrest (120) and the surface of the seat (110) are in a vertical angle state.

5. The adjustable-back office chair of claim 1, wherein: The ratchet (230) is rotatably installed on the inner side of the gear box (210), and one end thereof abuts against the surface of the ratchet wheel (220), the ratchet structure on the surface of the ratchet wheel (220) is engaged with the end of the ratchet (230) to realize the rotation locking of the back frame (121).

6. An adjustable back office chair according to claim 1, characterized in that: The tension spring (233) is in a stretched state, the pre-tightening force of the tension spring (233) is calibrated and set, so that when the ratchet (230) is not operated, the sliding pin rod (231) remains in the engaged locking state with the ratchet (230), and the stability of the backrest is ensured.

7. An adjustable back office chair according to claim 1, characterized in that: The gear box (210) is an integral injection molding structure, the inside thereof is provided with a limiting hole and a guide rail groove for limiting and guiding the movement path of the ratchet wheel (220), the ratchet (230) and the sliding pin rod (231).

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