Double-linkage back adjusting mechanism

Abstract

The utility model provides a double-linkage back adjusting mechanism which comprises a connecting support hinged to the front portion of a backrest base body, a connecting base is hinged to the front end of the connecting support, a movable support is hinged to the front end of the connecting base, and the hinge axis of the connecting base and the movable support is perpendicular to the hinge axis of the connecting support and the connecting base. The connecting frame and the connecting base are adopted as elastic connecting pieces for hinging the backrest base body and the movable support, compared with a single-spring structure, the elastic supporting range is larger, and better comfortable experience is achieved when a user backs on the backrest; the movable support swings in the vertical direction through rotatable matching of the connecting base and the connecting shaft so that the back of a user can still be supported under the conditions that the user sideways and the like, and the supporting device has the advantage of being wide in supporting range.

Description

Technical Field

[0001] The utility model relates to the technical field of seat back structure design, in particular to a double-linked back adjustment mechanism. Background Art

[0002] The flexibility and comfort of the seat backs on the market are poor, and they cannot change according to the user's sitting posture. They often cause back fatigue after users sit for a long time. As a common product, especially office chairs commonly used by office workers, how to effectively relieve users' back fatigue and pressure after sitting for a long time and improve the comfort of the seat backs is one of the strong demands for seat product optimization in the current market.

[0003] In order to solve the above problems, a seat back structure with a rebound function is designed in the prior art to improve the comfort of the backrest. For example, Chinese utility model patent with application number CN200720122492.7 discloses an automatically rebounding lumbar support structure for an office chair, comprising a lumbar support body and a chair back for supporting and installing the lumbar support body, wherein an outer sleeve protrudes vertically from the inner side of the lumbar support body, and an inner sleeve also protrudes from the chair back, wherein a shaft rod including a large diameter section and a small diameter section is formed in the inner sleeve, and a cylinder is formed inwardly recessed in the outer sleeve; a coil spring and a screw are also included, wherein the small diameter section is inserted into the cylinder and then screwed into the screw hole by means of the screw to be locked; the upper end of the inner side of the lumbar support body is always in contact with the chair back.

[0004] However, the above scheme only supports the user's back in the front and back directions through springs. When the user needs to move sideways or the like, the backrest cannot achieve a small swing in the vertical direction, resulting in poor comfort. In addition, since only the elastic force of the spring is used as support, the movable range of the backrest is also limited. In actual use, the elastic support effect is not obvious, which will also reduce the user's sitting comfort. Utility Model Content

[0005] The utility model proposes a double-linkage back adjustment mechanism to solve the problems in the prior art that the existing backrest with rebound function cannot be swung and adjusted in the vertical direction, has support limitations and poor comfort.

[0006] The technical solution of the utility model is achieved in this way:

[0007] A double-linked back adjustment mechanism comprises a connecting bracket hinged in front of a backrest base, a connecting seat hinged at the front end of the connecting bracket, a movable bracket hinged at the front end of the connecting seat, and a hinge axis between the connecting seat and the movable bracket being perpendicular to a hinge axis between the connecting bracket and the connecting seat.

[0008] Preferably, there are two connecting brackets and two connecting seats, and the two connecting brackets are located at upper and lower positions in front of the backrest base.

[0009] Preferably, a torsion spring is installed at the hinge axis between the connecting bracket and the backrest base.

[0010] Preferably, the movable bracket includes an internal skeleton, and the internal skeleton has two connecting shafts rotatably connected to the connecting seat.

[0011] Preferably, the connecting seat is arranged in a groove on the back of the internal frame, and springs are installed inside the connecting seat at two sides symmetrically relative to the connecting axis, with one end of the spring abutting against the connecting seat and the other end abutting against the back of the internal frame.

[0012] Preferably, a fixing frame is fixedly provided at the front position of the internal skeleton, and the connecting shaft is installed on the fixing frame.

[0013] Preferably, the surfaces of both ends of the connecting bracket are provided with outwardly protruding bumps, and the backrest base and the connecting seat are provided with limiting grooves for accommodating the movement of the bumps and limiting the bumps.

[0014] Preferably, the movable support further comprises an external frame installed outside the internal frame, and a cushion is installed on the external frame.

[0015] By adopting the above technical solution, the beneficial effects of the utility model are as follows:

[0016] (1) The utility model uses a connecting frame and a connecting seat as elastic connecting parts for hingedly connecting the backrest base and the movable bracket, which has a larger elastic support range than a single spring structure, and provides a better comfort experience when the user leans back;

[0017] (2) The utility model uses the rotatable cooperation of the connecting seat and the connecting shaft to realize the swing of the movable bracket in the vertical direction, so that the user's back can still be supported when the user turns sideways, etc., and has the advantage of a wide supporting range. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0019] Figure 1 It is a three-dimensional structural diagram of the utility model;

[0020] Figure 2It is an exploded view of the utility model;

[0021] Figure 3 It is an exploded view of the connection structure between the connection seat and the internal frame of the utility model;

[0022] Figure 4 It is an exploded view of the connection structure between the connection bracket and the connection seat of the utility model.

[0023] in:

[0024] 1. Backrest base; 2. Torsion spring; 3. Connecting bracket; 301. Bump; 4. Connecting seat; 401. Limiting groove; 5. Spring; 6. Internal frame; 601. Groove; 602. Mounting position; 7. Connecting shaft; 8. Fixing frame; 9. External frame; 10. Cushion. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] See also Figure 1-Figure 4 A double-linked back adjustment mechanism comprises a connecting bracket 3 hinged in front of a backrest base 1, wherein a torsion spring 2 is installed at the hinge axis of the connecting bracket 3 and the backrest base 1, wherein the backrest base 1 and the connecting bracket 3 are connected by a pin shaft, so that the connecting bracket 3 can rotate relative to the backrest base 1, and since the torsion spring 2 is installed at the hinge of the two, the torsion spring 2 always exerts an upward force on the connecting bracket 3. When the user leans back, pressure can be applied to the connecting bracket 3, and the elastic force of the torsion spring 2 can support the user's back.

[0027] A connecting seat 4 is hinged at the front end of the connecting bracket 3. There are two connecting brackets 3 and two connecting seats 4, and the two connecting brackets 3 are located at the upper and lower positions in front of the backrest base 1. The connecting brackets 3 and the connecting seat 4 at the upper and lower positions are mainly used to support the user's back and waist, respectively. A movable bracket is hinged at the front end of the connecting seat 4. The hinge axis of the connecting seat 4 and the movable bracket is perpendicular to the hinge axis of the connecting bracket 3 and the connecting seat 4. This arrangement allows the movable bracket to move in the front and rear directions relative to the backrest base 1, and to swing in the vertical direction, so that the backrest is more flexible, thereby improving the comfort of supporting the user's back and waist.

[0028] Specifically, the movable bracket includes an internal skeleton 6, and the internal skeleton 6 has two connecting shafts 7 rotatably connected to the connecting seat 4. More specifically, a fixing frame 8 is fixedly provided in the front position of the internal skeleton 6, and the connecting shaft 7 is installed on the fixing frame 8, wherein the fixing bracket is connected to the internal skeleton 6 by bolt connection, and the connecting shaft 7 is installed on the fixing frame 8, which is convenient for replacing the connecting shaft 7 when it is damaged later, and the maintenance cost is low.

[0029] Specifically, the connecting seat 4 is arranged in a groove 601 on the back side of the internal skeleton 6, and springs 5 ​​are installed inside the connecting seat 4 at two sides symmetrically relative to the connecting shaft 7. One end of the spring 5 abuts on the connecting seat 4 and the other end abuts on the back of the internal skeleton 6. There are two grooves 601, which are respectively located at the upper and lower positions on the back side of the connecting seat 4. The connecting shaft 7 can extend into the groove 601, which can be convenient for rotatable cooperation with the connecting seat 4. In order to limit the spring 5, the interior of the groove 601 has an installation position 602 for installing the spring 5, and the connecting seat 4 also has a blind hole for accommodating one end of the spring 5. When the user turns sideways, the internal skeleton 6 can swing under the action of the connecting shaft 7, and when the external force disappears, the spring 5 can reset the internal skeleton 6.

[0030] Specifically, the surfaces of both ends of the connecting bracket 3 have outwardly protruding bumps 301, and the backrest base 1 and the connecting seat 4 are provided with limiting grooves 401 for accommodating the movement of the bumps 301 and limiting the bumps 301 (the limiting grooves 401 at the position of the backrest base 1 are not shown in the figure). This arrangement is to avoid unlimited rotation at the two ends of the connecting bracket 3, so that the connecting bracket 3 has a certain range of rotation stroke.

[0031] Specifically, the movable bracket also includes an external frame 9 installed outside the internal frame 6, and a cushion 10 is installed on the external frame 9. In this embodiment, there are two external frames 9 and cushions 10, which correspond to the back position and waist position of the user respectively.

[0032] Working principle: When this double-linked back adjustment mechanism is in use, when the user sits down, the pressure of the backrest is applied to the movable bracket, so that the front end of the connecting bracket 3 rotates relative to the connecting seat 4, and the rear end of the connecting bracket 3 rotates relative to the backrest base 1. The movable bracket approaches the backrest base 1, and uses the elastic force of the torsion spring 2 as support to cushion the user's back and waist, thereby improving comfort; when the user turns sideways, the movable bracket can swing vertically relative to the connecting seat 4, thereby avoiding the problem of no support on one side of the user's back and greater support on the other side, further improving comfort.

[0033] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A double-linked back adjustment mechanism, characterized in that: It comprises a connecting bracket (3) hingedly connected to the front of the backrest base (1), the front end of the connecting bracket (3) is hingedly connected to a connecting seat (4), the front end of the connecting seat (4) is hingedly connected to a movable bracket, and the hinge axis between the connecting seat (4) and the movable bracket is perpendicular to the hinge axis between the connecting bracket (3) and the connecting seat (4); A torsion spring (2) is installed at the hinge axis between the connecting bracket (3) and the backrest base (1); The movable bracket comprises an internal frame (6), and the internal frame (6) has two connecting shafts (7) rotatably connected to the connecting seat (4).

2. A double-linked back adjustment mechanism according to claim 1, characterized in that: The number of the connecting bracket (3) and the connecting seat (4) is two, and the two connecting brackets (3) are located at upper and lower positions in front of the backrest base (1).

3. A double-linked back adjustment mechanism according to claim 1, characterized in that: The connecting seat (4) is arranged in a groove (601) on the back side of the internal frame (6), and springs (5) are installed inside the connecting seat (4) at two sides symmetrically relative to the connecting axis (7), with one end of the spring (5) abutting against the connecting seat (4) and the other end abutting against the back side of the internal frame (6).

4. A double-linked back adjustment mechanism according to claim 1, characterized in that: A fixing frame (8) is fixedly arranged in front of the internal frame (6), and the connecting shaft (7) is mounted on the fixing frame (8).

5. The double-linked back adjustment mechanism according to claim 1, characterized in that: The connecting bracket (3) has outwardly protruding bumps (301) on both end surfaces, and the backrest base (1) and the connecting seat (4) are provided with limiting grooves (401) for accommodating the movement of the bumps (301) and limiting the position of the bumps (301).

6. A double-linked back adjustment mechanism according to claim 1, characterized in that: The movable support further comprises an external frame (9) installed outside the internal frame (6), and a cushion (10) is installed on the external frame (9).

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