Backrest height adjustment device

Abstract

The invention discloses a backrest height adjustment device, comprising a back frame and a supporting frame, wherein the back frame and the supporting frame are slidably matched; a sliding limit mechanism is arranged between the back frame and the supporting frame, and the sliding limit mechanism comprises a limit pin, a limit groove and a control switch for controlling the lateral movement of the limit pin; the control switch and the back frame are slidably matched, and the upper and lower ends of the control switch both protrude from the rear end of the back frame to form upper and lower pressing parts; when the back frame is in use, the limit pin is inserted into the limit groove; when the back frame is in an adjustment state, the upper pressing part is forced downward so that the lower pressing part protrudes downward to form a first adjustment direction identification body, or the lower pressing part is forced upward so that the upper pressing part protrudes upward to form a second adjustment direction identification body, and at the same time the limit pin leaves the limit groove, and the back frame is forced to move along the movement direction of the control switch; the operation is quick and labor-saving, simple and practical.

Description

Technical Field

[0001] The invention relates to the field of seating, and in particular to a backrest height adjustment device. Background Art

[0002] The backrest height of existing chairs on the market is often set at the factory, which is not convenient to adjust and has a narrow application range. Sometimes the backrest is too high for shorter people, and too low for taller people. The same person sometimes needs a higher backrest and sometimes needs a lower backrest. Existing chairs cannot meet these personalized requirements. Therefore, there is an urgent need for a chair that can be used for people of different heights and has an adjustable backrest height.

[0003] The Chinese invention patent CN201611224078.7 discloses a "chair with adjustable backrest height", which includes a seat, a backrest and a chair leg, the backrest includes a fixed part and a lifting part, the fixed part includes columns on both sides and a wide backrest plate in the middle; the lifting part includes lifting columns on both sides, a lifting backrest plate in the middle and a horizontal plate connecting them as a whole; a plurality of height positioning holes are provided in the vertical direction of the columns, and elastic pins that can be exposed from the corresponding height positioning holes are provided in the lifting columns, and the lifting columns are movably inserted into the columns; the lifting backrest plate and the wide backrest plate are in contact with each other back to back, so that the height of the lifting part can be adjusted by pressing the elastic pin as needed, thereby meeting the backrest height requirements of different users. When the chair is to be stored, the lifting part is adjusted to the lowest to save storage space. Therefore, the structure of the present invention is more reasonable, suitable for a wider range of people, and more convenient to store. Although the chair can adjust the backrest height, it is achieved by pressing the spring pin and cooperating with different positioning holes. As a result, the back frame height can only be adjusted by pressing in sections, and the back frame cannot be adjusted freely in height smoothly; and the spring pin sometimes gets stuck, resulting in a jamming phenomenon when adjusting the height. Summary of the invention

[0004] The present invention overcomes the deficiencies in the above-mentioned prior art and provides a simple, practical and easy-to-operate backrest height adjustment device, in which the height of the back frame is adjusted by adjusting a control switch; the control switch has an upper and a lower pressing part, and when the upper pressing part is forced downward, the lower pressing part protrudes downward again to form a first adjustment direction mark, or when the lower pressing part is forced upward, the upper pressing part protrudes upward again to form a second adjustment direction mark, and at the same time, the limit pin leaves the limit groove, and the back frame is forced to move along the movement direction of the control switch; the overall structure is simple, which can make the operation of the back frame quick and labor-saving, and the adjustment is smooth during the adjustment process, and can be suitable for people of various body shapes to meet the needs of different individual differences.

[0005] The technical solution of the present invention is achieved in this way:

[0006] A backrest height adjustment device, characterized in that it comprises a back frame and a supporting frame, the back frame is connected to the supporting frame and there is a sliding fit between the back frame and the supporting frame; a sliding limit mechanism is provided between the back frame and the supporting frame, the sliding limit mechanism comprises a pair of limit pins arranged on the back frame, a plurality of limit grooves vertically arranged on the supporting frame and a control switch for controlling the lateral movement of the limit pin; the control switch is slidably fitted with the back frame, and the upper and lower ends of the control switch both protrude from the rear end of the back frame, and the protruding part of the control switch forms an upper and lower pressing part; when the back frame is in use, the limit pin is inserted into the limit groove; when the back frame is in an adjustment state, the upper pressing part is forced downward so that the lower pressing part protrudes downward again to form a first adjustment direction identification body, or the lower pressing part is forced upward so that the upper pressing part protrudes upward again to form a second adjustment direction identification body, and at the same time the limit pin leaves the limit groove, and the back frame is forced to move along the movement direction of the control switch. The invention can adjust the height of the back frame by pressing the upper and lower pressing parts of the control switch to control the locking and unlocking states of the limiting groove of the limiting pin, and the control is convenient and practical.

[0007] Preferably, the control switch has a left-right symmetrical limit pin guide groove, the limit pin guide groove has two symmetrical upper and lower bevels, the limit pin has a guide column protruding from the outer wall of the limit pin, the guide column is located in the limit pin guide groove and the guide column abuts against the bevel, the upper bevel is formed by the intersection of the upper and lower bevels tilting upward toward the middle position of the control switch, and the lower bevel is formed by the intersection of the upper and lower bevels tilting downward toward the middle position of the control switch. The longitudinal movement of the control switch is converted into the lateral movement of the limit pin through the cooperation of the upper and lower bevels of the limit pin guide groove and the guide column.

[0008] Preferably, when the back frame is in the adjustment state, the control switch moves downward, the guide column and the upper bevel are matched and move relative to each other; when the control switch moves upward, the guide column and the lower bevel are matched and move relative to each other. When the back frame is in the adjustment state, when the upper and lower pressing parts are pressed, the upper pressing part is forced downward, and the guide column moves to the upper vertex of the upper bevel; or the lower pressing part is forced upward, and the guide column moves to the lower vertex of the lower bevel.

[0009] Preferably, the back frame includes a lower crossbar and back side bars located on both sides of the lower crossbar, and the support frame includes a horizontal connecting bottom plate and a longitudinal support frame; the lower crossbar is slidably matched with the support frame, the rear end of the lower crossbar is connected to a back cover, the control switch is in the support frame, and the support frame is clamped between the lower crossbar and the back cover. The back cover makes the connection between the support frame and the lower crossbar more stable.

[0010] Preferably, the support frame includes side bars on both sides, and the rear end of the lower cross bar is symmetrically provided with mounting grooves on the left and right sides; a convex rib is provided in the mounting groove, and a vertical guide groove is correspondingly provided at the front end of the side bar; the side bar is located in the mounting groove, and the convex rib is embedded in the guide groove. The convex rib is embedded in the guide groove and slides up and down, so that the sliding between the back frame and the support frame is stable and the shaking feeling is eliminated; the side bar is located in the mounting groove, so that the connection between the back frame and the support frame is tighter and not easy to loosen.

[0011] Preferably, a transverse groove is provided between the installation grooves, the limit pins are symmetrically arranged in the transverse grooves on the left and right, the limit pins are clamped between the lower cross bar and the control switch, and a spring is connected between the two limit pins. The transverse groove is provided so that the limit pins always move in the transverse groove and will not be separated up and down, and the springs between the limit pins make the guide column on the limit pin always abut against the bevel of the limit pin guide groove.

[0012] Preferably, the control switch is vertically arranged at the middle position of the lower cross bar, and the lower cross bar and the rear cover are provided with corresponding slide grooves, the control switch is clamped between the lower cross bar and the rear cover, and the control switch is located in the slide groove.

[0013] Preferably, an elastic waist support is disposed transversely in the middle of the back frame, and the two ends of the elastic waist support are respectively connected and fixed to the back side plates on both sides of the back frame. The elastic support plate provides back support for the human body during use, making the human body feel more comfortable.

[0014] The design starting point, concept and beneficial effects of the present invention using the above technical solution are:

[0015] 1. The mechanism is simple and ingenious. It only requires setting a control switch and a limit pin between the back frame and the supporting frame. The limit pin can be inserted into or out of the limit slot through the control switch to adjust the height of the back frame.

[0016] 2. Easy to operate and adapt to human usage habits. The control switch has upper and lower pressing parts. When the back frame needs to be raised, just press the lower pressing part upward to force the back frame to slide upward; when the back frame needs to be lowered, press the upper pressing part downward to force the back frame to slide downward; the movement direction of the back frame is consistent with that of the control switch; release the upper and lower pressing parts, and the locking pin will be reset and locked in the limit groove under the action of the spring. The use process is simple and very user-friendly.

[0017] 3. Easy to install and can adapt to different seats. When installing, you only need to connect and fix the connecting base plate on the support frame to the seat. It is connected by screws, does not require a specific structure, is quick to install, and has high adaptability.

[0018] 4. The adjustment is smooth and there is a good damping feeling. During the adjustment of the back frame, the convex ribs on the back frame slide in the guide grooves on the side rods of the support frame. The sliding is smooth without any jamming. When the control switch is pressed, the spring force between the limit pins makes the operation process have a good damping feeling and the operating experience is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the three-dimensional structure of the backrest height adjustment device in an embodiment of the present invention;

[0020] Figure 2 It is a rear exploded view of a backrest height adjustment device in an embodiment of the present invention;

[0021] Figure 3 It is a front exploded view of a backrest height adjustment device in an embodiment of the present invention;

[0022] Figure 4 is a schematic diagram of the three-dimensional structure of the back frame in an embodiment of the present invention;

[0023] Figure 5 It is a schematic diagram of the three-dimensional structure of the support frame in an embodiment of the present invention;

[0024] Figure 6 is a schematic diagram of the three-dimensional structure of the back frame in the embodiment of the present invention when it is in use;

[0025] Figure 7 It is a schematic diagram of the three-dimensional structure when the back frame is adjusted to slide upward along the support frame in an embodiment of the present invention;

[0026] Figure 8 It is a schematic diagram of the three-dimensional structure when the back frame is adjusted to slide downward along the support frame in an embodiment of the present invention;

[0027] The figures are marked as follows: back frame 1; support frame 2; sliding limit mechanism 3; upper cross bar 4; lower cross bar 5; back side bar 6; connecting base plate 7; support frame 8; side bar 9; mounting groove 10; guide groove 11; convex rib 12; back cover 13; limit pin 14; limit groove 14a; control switch 15; transverse groove 16; spring 17; slide groove 18; limit pin guide column 19; upper bevel 20; lower bevel 21; guide column 22; intersection of upper and lower bevels 23; elastic lumbar support 24; upper pressing portion 25; lower pressing portion 26; first condition identification body 27; second adjustment identification body 28. DETAILED DESCRIPTION

[0028] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. 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.

[0029] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0030] In the description of the present invention, the term "at least one" refers to one or more than one, unless otherwise clearly defined. The terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0031] The specific implementation methods of the present invention are as follows:

[0032] like Figure 1-8 As shown, the present invention provides a backrest height adjustment device, comprising a backrest frame 1 and a support frame 2 , wherein a sliding limit mechanism 3 is provided between the backrest frame 1 and the support frame 2 .

[0033] like Figure 1-5 As shown, the back frame 1 is connected to the support frame 2. The back frame 1 is a "mouth" shaped frame. The back frame 1 includes upper and lower cross bars 4, 5 and back side bars 6 located on both sides of the upper and lower cross bars 4, 5. The support frame 2 includes a transverse connecting base plate 7 and a longitudinal support frame 8; and the lower cross bar 5 and the support frame 8 are slidably matched. Specifically, the support frame 8 includes side bars 9 located on both sides, and corresponding mounting grooves 10 are symmetrically provided on the left and right sides of the rear end of the lower cross bar 5, and the mounting groove 10 is provided with a convex rib 12 protruding backward, and the front end of the side bar 9 is provided with a vertical guide groove 11; during installation, the side bar 9 is installed in the mounting groove 10, and the convex rib 12 is embedded in the guide groove 11, and the convex rib 12 slides up and down along the guide groove 11. After the side bar 9 and the lower cross bar 5 are slidably matched, as shown Figure 3 As shown, a rear cover 13 is fixed to the rear end of the lower cross bar 5 by screws, the support frame 8 is clamped between the lower cross bar 5 and the rear cover 13, and the two sides of the rear cover 13 are respectively abutted against the rear end surface of the side bar 9, so that the connection between the back frame 1 and the support frame 8 is more stable.

[0034] like Figure 2 , 3 As shown in Figures 4 and 6, the sliding limit mechanism 3 is located between the lower cross bar 5 and the support frame 8. The sliding limit mechanism 3 includes a pair of limit pins 14 arranged on the back frame 1, a plurality of limit slots 14a vertically arranged on the support frame 8, and a control switch 15 for controlling the lateral movement of the limit pins 14.

[0035] like Figure 4As shown, a transverse groove 16 is provided between the two mounting grooves 10 of the lower cross bar 5, and the two limit pins 14 are symmetrically arranged in the transverse groove 16 on the left and right, and the limit pin 14 can move laterally in the transverse groove 16, and a spring 17 is also provided between the two limit pins 14, and the two ends of the spring 17 are respectively connected and fixed to the limit pin 14; the limit pin 14 is clamped between the lower cross bar 5 and the control switch 15, and the control switch 15 is rectangular, and the control switch 15 and the lower cross bar 5 are slidably matched, which specifically means that: the control switch 15 is vertically arranged at the middle position of the lower cross bar 5, and the lower cross bar 5 and the rear cover 13 are correspondingly provided with a slide groove 18. During installation, after the rear cover 13 is connected to the lower cross bar 5, The control switch 15 is in the support frame 8, and the control switch 15 is clamped in the slide groove 18 of the lower cross bar 5 and the rear cover 13, and the control switch 15 slides up and down in the slide groove; the upper and lower ends of the control switch 15 protrude from the rear cover 13, and the protruding parts of the control switch 15 form upper and lower pressing parts 25 and 26 respectively; the control switch 15 is provided with a left-right symmetrical limit pin guide groove 19, and the limit pin guide groove 19 has two symmetrical upper and lower bevels 20 and 21, and the upper bevel 20 is formed by the intersection point 23 of the upper and lower bevels and tilted upward toward the middle position of the control switch 15, and the lower bevel 21 is formed by the intersection point 23 of the upper and lower bevels and tilted downward toward the middle position of the control switch 15. The stop pin 14 has a guide post 22 protruding from the outer wall of the stop pin. The guide post 22 is located in the stop pin guide groove 19 and the guide post 20 abuts against the upper and lower bevels 20 and 21. The spring 17 between the two stop pins 14 is always in a compressed state, so that the stop pin 14 is subjected to the spring force, ensuring that the guide post 22 always abuts against the upper and lower bevels 20 and 21 during the sliding process of the control switch 15. Figure 5 As shown, the limiting grooves 14a are arranged on the inner side of the side rod 9 along the longitudinal direction.

[0036] like Figure 1 , 4 As shown, during installation, it is only necessary to connect and fix the connecting base plate 7 to the seat of the chair by screws, without the need for a specific structure, and the installation is quick and has high adaptability. An elastic waist support 24 is also horizontally arranged in the middle of the back frame 1, and the two ends of the elastic waist support 24 are respectively connected to the back side plates 6 on both sides of the back frame 1, which makes the human body more comfortable when used and provides better support for the back.

[0037] Working principle: When the back frame 1 is in use, Figure 6As shown, the limit pin 14 is inserted into the limit groove 16, the spring 19 between the two limit pins 14 is in a pre-tightened state, and the guide column 22 on the limit pin 14 abuts against the upper and lower oblique intersection points 23 of the limit pin guide groove 19. At this time, the back frame 1 and the support frame 8 are slidingly locked.

[0038] When the back frame 1 is in the adjustment state, if the height of the back frame 1 needs to be lowered, Figure 8 As shown, the upper pressing portion 25 is pressed downward, so that the control switch 15 slides downward, and the lower pressing portion 26 protrudes downward again to form a first adjustment direction identification body 27. At the same time, the guide column 22 and the upper bevel 20 are matched and relatively moved, and the two limit pins 14 move inward respectively, and the spring 19 between the limit pins 14 is compressed, and the limit pins 14 leave the limit groove 15, and the back frame 1 is forced to slide downward; if it is necessary to raise the height of the back frame 1, as shown in FIG. Figure 7 As shown, the lower pressing part 26 is pressed upward, so that the control switch 15 slides upward, and the upper pressing part 25 protrudes upward again to form a second adjustment direction identification body 28. At the same time, the guide column 22 and the lower bevel 20 are matched and relatively moved, and the two limit pins 14 move inward respectively, and the spring 19 between the limit pins 14 is compressed, and the limit pin 14 leaves the limit groove 15, and the back frame 1 is forced to slide upward. When the height adjustment of the back frame 1 is completed, the upper and lower pressing parts 25 and 26 are released, and the locking pin 14 is reversely reset and inserted into the limit groove 14a under the action of the spring 17 reset elastic force. The use process is simple and very in line with human use habits, which is more humane.

Claims

1. A backrest height adjustment device, characterized in that: The invention comprises a back frame and a supporting frame, wherein the back frame is connected to the supporting frame and the back frame and the supporting frame are slidably matched; a sliding limit mechanism is provided between the back frame and the supporting frame, and the sliding limit mechanism comprises a pair of limit pins arranged on the back frame, a plurality of limit grooves vertically arranged on the supporting frame, and a control switch for controlling the lateral movement of the limit pin; the back frame comprises a lower cross bar and a back side bar located on both sides of the lower cross bar, the rear end of the lower cross bar is symmetrically provided with mounting grooves on the left and right, a transverse groove is provided between the mounting grooves, the two limit pins are symmetrically arranged in the transverse grooves on the left and right, and the limit pins can move transversely in the transverse grooves, the limit pins are clamped between the lower cross bar and the control switch, and a spring is connected between the two limit pins, and the two ends of the spring are respectively connected and fixed to the limit pins; a limit pin guide groove symmetrically arranged on the control switch is provided, and the limit pin guide groove has two symmetrical upper and lower bevels, and the upper bevel is formed by the intersection of the upper and lower bevels and tilting upward toward the middle position of the control switch. The lower bevel is formed by the intersection of the upper and lower bevels tilting downward toward the middle position of the control switch; the limit pin is provided with a guide column protruding from the outer wall of the limit pin, the guide column is located in the limit pin guide groove and the guide column is in abutment with the upper and lower bevels, and the spring between the two limit pins is always in a compressed state, so that the limit pin is subjected to the spring elastic force, ensuring that during the sliding process of the control switch, the guide column is always in abutment with the upper and lower bevels; the control switch is slidably matched with the back frame, and the upper and lower ends of the control switch protrude from the rear end of the back frame, and the protruding part of the control switch forms the upper and lower pressing parts; when the back frame is in use, the limit pin is inserted into the limit groove; when the back frame is in an adjustment state, the upper pressing part is forced downward so that the lower pressing part protrudes downward again to form a first adjustment direction identification body, or the lower pressing part is forced upward so that the upper pressing part protrudes upward again to form a second adjustment direction identification body, and at the same time, the limit pin leaves the limit groove, and the back frame is forced to move along the movement direction of the control switch.

2. The backrest height adjustment device according to claim 1, characterized in that: When the back frame is in the adjustment state, the control switch moves downward, the guide column and the upper bevel are matched and move relative to each other; the control switch moves upward, the guide column and the lower bevel are matched and move relative to each other.

3. The backrest height adjustment device according to claim 1, characterized in that: The support frame includes a transverse connecting base plate and a longitudinal support frame; the lower cross bar is slidably matched with the support frame, the rear end of the lower cross bar is connected to a back cover, the control switch is in the support frame, and the support frame is clamped between the lower cross bar and the back cover.

4. The backrest height adjustment device according to claim 3, characterized in that: The support frame includes side bars on both sides; a convex rib is provided in the installation groove, and a vertical guide groove is correspondingly provided at the front end of the side bar; the side bar is located in the installation groove, and the convex rib is embedded in the guide groove.

5. The backrest height adjustment device according to claim 3, characterized in that: The control switch is vertically arranged at the middle position of the lower cross bar, and the lower cross bar and the rear cover are both provided with corresponding slide grooves, the control switch is clamped between the lower cross bar and the rear cover, and the control switch is located in the slide groove.

6. The backrest height adjustment device according to claim 3, characterized in that: An elastic waist support is transversely arranged in the middle of the back frame, and two ends of the elastic waist support are respectively connected and fixed to the back side plates on both sides of the back frame.

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