Quick-release backrest device

Abstract

The utility model discloses a quick-release backrest device which comprises a backrest, the backrest comprises a backrest body and a connecting arm detachably connected with the backrest body, and the backrest body is provided with an assembly position with a sliding-in opening and a limiting part. A sliding block capable of sliding into the assembling position along the sliding inlet is arranged at the position, corresponding to the assembling position, of the connecting arm, after the sliding block is assembled in the assembling position, the limiting part is used for limiting the sliding block in the assembling position, the backrest body can be detached from the connecting arm, and the backrest body can be detached from the connecting arm. The backrest body can be conveniently replaced after being abraded or the style is old, the backrest body and the sliding block can be rapidly positioned during disassembly and replacement in a sliding-in assembly mode, the whole process is simple and rapid, and after the position of the sliding block is limited by the limiting block, the backrest body is firmly installed and does not easily fall off.

Description

Technical Field

[0001] The utility model belongs to the technical field of vehicle seat accessories, and in particular relates to a quick-detachable backrest device. Background Art

[0002] Motorcycles, electric vehicles, and bicycles are common means of transportation. In order to better improve the comfort and safety of the vehicles, people have designed backrests that can be connected to the frame to provide support behind the driver or passengers. The backrest includes a support arm connected to the frame and a backrest body connected to the support arm. The backrest body currently used is usually not removable and replaceable, which invisibly increases the cost. Utility Model Content

[0003] Aiming at the technical problem in the prior art that a backrest body cannot be replaced after being worn, the utility model provides a quick-detachable backrest device.

[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0005] A quick-release backrest device comprises a backrest, wherein the backrest comprises a backrest body and a connecting arm detachably connected to the backrest body, the backrest body is provided with an assembly position having a sliding entrance and a limiting portion, the connecting arm is provided with a sliding block which can slide into the assembly position along the sliding entrance at a position corresponding to the assembly position, and when the sliding block is assembled in the assembly position, the limiting portion is used to limit the sliding block in the assembly position.

[0006] Further, the assembly position includes a U-shaped slide groove recessed toward the inner direction of the backrest body, the opening of the U-shaped slide groove forms a slide entrance for the slider to freely enter and exit, and a side wall of the U-shaped slide groove is formed with a stopper for preventing the slider from detaching from the backrest body in a direction away from the backrest body;

[0007] The limiting portion is configured as a limiting block capable of closing the sliding entrance.

[0008] Furthermore, the enclosure has a covering portion that can partially cover the U-shaped slide groove, and the bottom surface of the covering portion and the side wall of the U-shaped slide groove can form an L-shaped assembly portion that is slidably connected to the slider. When the slider is assembled in the U-shaped slide groove, the covering portion can be pressed on the outer surface of the slider.

[0009] Furthermore, the limiting block has a limiting body which is blocked on the outer side of the sliding block along the entry and exit direction of the sliding block, and the limiting body is detachably arranged at the sliding entrance.

[0010] Further, the limiting block further has a pressing portion connected to the limiting body and capable of pressing against the outer surface of the slider. The pressing portion is configured to be connected end to end with the covering portion to form a frame structure for forming a barrier around the outer surface of the slider to prevent the slider from detaching from the backrest body in a direction away from the backrest body.

[0011] Further, the lengths of the two L-shaped assembly portions on the U-shaped sliding groove that are parallel to the sliding direction of the slider are greater than the length of the slider in this direction. After the slider slides into the bottom of the U-shaped sliding groove, the two L-shaped assembly portions protrude out of the outer side of the slider in the direction of the sliding inlet, and the two portions protruding out of the outer side of the slider respectively form two limiting spaces.

[0012] Restricted portions capable of extending into the limiting spaces along the sliding direction of the slider are formed at both ends of the pressing portion.

[0013] A number of first reinforcing holes are provided on the limiting body, and a number of corresponding second reinforcing holes are also provided at corresponding positions of the U-shaped sliding groove. The first reinforcing holes and the second reinforcing holes are screwed together by reinforcing bolts.

[0014] Further, the slider has an angle adjustment portion capable of rotatably connecting with the connecting arm.

[0015] Further, the angle adjustment portion is configured as a pitch angle adjustment portion for adjusting the pitch angle of the backrest body and / or a horizontal angle adjustment portion for adjusting the horizontal angle of the backrest body.

[0016] Further, the connecting arm has two connecting wings arranged horizontally at intervals. A connecting position for installing the pitch angle adjustment portion is formed between the two connecting wings. The pitch angle adjustment portion installed in the connecting position can rotate around its own axis to adjust the pitch angle of the backrest body, and the adjustment position of the pitch angle adjustment portion is locked by a first angle locking mechanism.

[0017] Further, the first angle locking mechanism includes first angle locking portions symmetrically arranged on both sides of the pitch angle adjustment portion, second angle locking portions provided on the connecting wings and connected to the first angle locking portions in a one-to-one correspondence, two angle locking knobs symmetrically arranged at intervals and movably connected in the first angle locking portions and the second angle locking portions, and a return spring arranged between the two angle locking knobs. When the two angle locking knobs are pressed towards each other, the angle locking knobs move towards the direction close to the first angle locking portion and separate from the second angle locking portion. When the angle locking knobs are released, the return spring drives the two angle locking knobs to return and lock the positions of the first angle locking portion and the second angle locking portion.

[0018] The first angle locking part includes a first locking cavity provided on the side wall of the pitching angle adjusting part, a plurality of first tooth parts arranged at intervals around the inner peripheral surface of the first locking cavity, and a guiding groove arranged coaxially with the first locking cavity and surrounding the first locking cavity therein. The two symmetrically arranged first locking cavities are communicated through a first through hole, and the inner diameter of the first through hole is smaller than the inner diameter of the first locking cavity;

[0019] The second angle locking part includes a second locking cavity provided on the inner wall of the connecting wing, a plurality of second tooth parts arranged at intervals around the inner peripheral surface of the second locking cavity and corresponding to the first tooth parts, a ring flange protruding from the inner wall of the connecting wing in a direction away from the inner wall of the connecting wing and capable of being in clearance fit with the guiding groove, and a second through hole arranged on the outer wall of the connecting wing and penetrating inward in the direction of the second locking cavity. The inner diameter of the second through hole is smaller than the inner diameter of the second locking cavity;

[0020] The angle locking knob includes a knob body with an installation opening at one end, and a plurality of third tooth parts arranged at intervals around the outer periphery of the knob body. The blind end of the knob body is exposed outside the connecting wing, and after the other relatively open end enters the second through hole, the third tooth parts are engaged with the first tooth parts and the second tooth parts, so as to lock the pitching angle adjusting part and the connecting wing. The two ends of the return spring are respectively located in the inner cavities of the two knob bodies after passing through the first through hole;

[0021] When pressing the blind ends of the two knob bodies, the plurality of third tooth parts of the two knob bodies move in a direction close to the first tooth parts until the third tooth parts enter the gaps between the first tooth parts one by one, so that the return spring is compressed and the third tooth parts are separated from the second tooth parts; when the pressing on the angle locking knob is released, the return spring returns to drive the angle locking knob to return, and the third tooth parts return to be engaged with the first tooth parts and the second tooth parts, for locking the pitching angle adjusting part and the connecting arm.

[0022] Further, the connecting arm includes a telescopic arm and an arm main body in which the telescopic arm is movably installed. The telescopic arm can reciprocate inside the arm main body. One end of the telescopic arm away from the backrest main body is provided with a first installation groove for installing an elastic member, and a second installation groove connected to the elastic member is provided at a position corresponding to the elastic member inside the arm main body. The arm main body is connected with a telescopic locking mechanism for locking the position of the telescopic arm; when the telescopic arm is in the original non-telescopic state, the elastic member is in a stretched state to store elastic force, and when the locking of the telescopic locking mechanism is unlocked, the elastic member can drive the telescopic arm to move in a direction away from the arm main body.

[0023] Further, the elastic member is a constant-force spring with a T-shaped clamping portion at one end. The first installation groove is an arc groove adapted to the outer peripheral surface of the constant-force spring, and the second installation groove is cooperatively connected with the T-shaped clamping portion.

[0024] In summary, the quick-release backrest device has the following beneficial effects: First, the backrest body can be disassembled from the connecting arm, which is convenient for replacing the backrest body when it is worn or out of style. Moreover, in the way of sliding-in assembly, when disassembling and replacing, the backrest body and the slider can be quickly positioned, and the whole replacement and assembly process is simple, fast and easy to operate. Second, the periphery of the slider is pressed by the covering portion and the pressing portion to form a stable and firm fixing structure, which increases the supporting strength at the connection after limiting. Third, the first angle adjustment mechanism can adjust the pitching angle of the backrest body according to the actual situation of the user, so that the using surface of the backrest body can support and rely on people more fittingly. Moreover, after adjusting the angle of the pitching angle adjustment portion, it is locked by two knob bodies. The third tooth portions on the two knob bodies can mesh more tightly with the first tooth portion and the second tooth portion, improving the locking effect and being more firm and reliable when locking the angle. Fourth, the connecting arm can also be adjusted in length. According to the different lengths required by different users for the backrest body, the telescopic arm reciprocates in the arm body, and then the position of the telescopic arm is locked through the telescopic locking mechanism to complete the adjustment of the length of the connecting arm. Fifth, the connecting arm is connected to the two-wheeled vehicle through the connecting frame. By rotating the locking handle, the pin head can withdraw from the locking hole, and the connecting arm is rotated to realize the angle adjustment. After the third return spring drives the pin head to return to its position, the position of the locking connecting plate is locked, and the connecting arm can be adjusted in pitching angle as needed. Sixth, during the process of rotating and adjusting the connecting arm, the positioning beads in the elastic mechanism can enter and exit the locking hole, and collide with the edge of the locking hole during the positioning process. The adjustment gears are clear and obvious, and there is an obvious adjustment feel. After the distances between each locking hole are equal, through the number of times of positioning by the elastic mechanism, the specific adjustment angle can be known during each adjustment process, avoiding the situation of under-adjustment or over-adjustment. Description of the Drawings

[0025] Figure 1 is a schematic structural diagram of a quick-release backrest device provided by the present invention.

[0026] Figure 2 is a schematic structural diagram of the backrest body without installing the slider in the present invention.

[0027] Figure 3 is a front projection view of the backrest body after installing the slider in the present invention.

[0028] Figure 4 is Figure 3 the sectional view taken along the line A-A of

[0029] Figure 5It is a three-dimensional structural schematic diagram of the limit block in the present utility model.

[0030] Figure 6 It is a top view of the backrest in the present utility model.

[0031] Figure 7 It is Figure 6 a cross-sectional view taken along the B-B direction in

[0032] Figure 8 It is Figure 7 a partial enlarged view of part A in

[0033] Figure 9 It is a structural schematic diagram of the first angle locking part in the present utility model.

[0034] Figure 10 It is a structural schematic diagram of the second angle locking part in the present utility model.

[0035] Figure 11 It is a top view of the telescopic arm in the present utility model.

[0036] Figure 12 It is a vertical cross-sectional view of the telescopic locking mechanism in the present utility model.

[0037] Figure 13 It is a cross-sectional view of the second angle locking mechanism in the present utility model.

[0038] Figure 14 It is a structural schematic diagram of the connecting part in the present utility model.

[0039] Figure 15 It is a structural schematic diagram of the connecting plate in the present utility model.

[0040] Figure 16 It is a structural schematic diagram of the lock part in the present utility model.

[0041] Figure 17 It is a cross-sectional view of the elastic mechanism in the present utility model.

[0042] In the figure, 100 - backrest body, 110 - cushion, 120 - U-shaped chute, 121 - retaining wall, 1210 - covering part, 122 - second reinforcing hole, 130 - limiting block, 131 - limiting main body, 1310 - first reinforcing hole, 132 - pressing part, 1320 - restricted part, 140 - reinforcing bolt, 141 - convex part, 200 - connecting arm, 210 - telescopic arm, 211 - arm head, 2110 - connecting wing, 2110A - connecting position, 212 - arm rod, 220 - arm main body, 221 - branch arm, 2210 - connecting part, 2210A - through hole, 2210B - material-saving groove, 300 - slider, 310 - pitching angle adjusting part, 400 - first angle locking mechanism, 410 - first angle locking part, 411 - first locking cavity, 412 - first tooth part, 413 - guiding groove, 4130 - reinforcing rib, 414 - first through hole, 420 - second angle locking part, 421 - second locking cavity, 422 - second tooth part, 423 - annular flange, 424 - second through hole, 430 - angle locking knob, 431 - knob body, 432 - third tooth part, 440 - return spring, 500 - telescopic locking mechanism, 510A - annular protrusion, 510B - first fitting cavity, 510C - third fitting cavity, 510D - stepped groove, 520 - telescopic fitting part, 520A - first fitting space, 520B - second fitting space, 530A - locking button, 530B - spring sleeve section, 530C - first fitting section, 530D - first limiting section, 530E - second fitting section, 530F - second limiting section, 530H - tail section, 540 - first return spring, 600 - adapter shaft, 610 - limit nut, 620 - covering part, 700 - connecting plate, 710 - locking hole, 800 - locking part, 810 - locking pin, 811 - pin head, 812 - pin rod, 813 - support rod, 820 - third return spring, 830 - locking handle, 831 - handle, 832 - handle head, 8320 - smooth cut surface, 833 - receiving notch, 900 - elastic mechanism, 910 - insert part, 920 - second return spring, 930 - positioning bead. Detailed implementation mode

[0043] The present utility model will be further described below in conjunction with specific illustrations.

[0044] Please refer to Figure 1, the present utility model provides a quick-release backrest device, including a backrest, which includes a backrest body 100 and a connecting arm 200 detachably connected to the backrest body 100. The backrest body 100 is provided with an assembly position having a sliding inlet and a limiting portion. The connecting arm 200 is provided with a slider 300 at a position corresponding to the assembly position, which can slide into the assembly position along the sliding inlet. After the slider 300 is assembled in the assembly position, the limiting portion is used to limit the slider 300 in the assembly position. The backrest body 100 can be disassembled from the connecting arm 200, which is convenient for replacing the backrest body 100 after wear or out-of-date style. Moreover, in the way of sliding into the assembly, when disassembling and replacing, the backrest body 100 and the slider 300 can be quickly positioned, and the whole process is simple and fast.

[0045] One end of the backrest body 100 away from the assembly position has a cushion 110. For the convenience of users, the contact surface of the cushion 110 is preferably an arc surface.

[0046] Please refer to Figure 2 , the assembly position includes a U-shaped chute 120 recessed towards the inside of the backrest body 100. The opening of the U-shaped chute 120 forms a sliding inlet for the slider 300 to freely enter and exit. A retaining wall 121 for preventing the slider 300 from detaching from the backrest body 100 in the direction away from the backrest body 100 is formed at the side wall of the U-shaped chute. The retaining wall 121 has a covering portion 1210 that can partially cover the U-shaped chute 120. The bottom surface of the covering portion 1210 and the side wall of the U-shaped chute 120 can form an L-shaped assembly portion for sliding connection with the slider 300. Please refer to Figure 3 and Figure 4 , after the slider 300 is assembled in the U-shaped chute 120, the covering portion 1210 can press against the outer surface of the slider 300. The two sides of the slider 300 cooperate with the L-shaped assembly portion, so that after the slider 300 is assembled in the U-shaped chute 120, the covering portion 1210 can press against the outer surface of the slider 300. This pressing effect not only restricts the movement of the slider 300 in the horizontal direction, but also provides additional support in the vertical direction through the L-shaped structure of the L-shaped assembly portion, thereby enhancing the overall fixing effect. Due to the tight fit between the L-shaped assembly portion and the slider 300, the shaking of the slider 300 caused by external forces (such as vibration, impact, etc.) is reduced, and the stability and reliability of the entire assembly structure are improved. In addition, the presence of the L-shaped assembly portion makes the assembly process of the slider 300 simpler and faster. The user only needs to align the slider 300 with the sliding inlet and then push it along the U-shaped chute 120, without additional assembly steps or tools, which greatly improves the assembly efficiency and the disassembly and assembly are fast. The design of the retaining wall 121 and its covering portion 1210 effectively prevents the risk of the slider 300 falling off in the direction away from the backrest body 100 during the assembly process or use process, and improves the safety performance of the product.

[0047] The lengths of the two L-shaped assembly parts on the U-shaped chute 120 that are parallel to the access direction of the slider 300 are greater than the length of the slider 300 in this direction. After the slider 300 slides into the bottom of the U-shaped chute 120, the two L-shaped assembly parts protrude outwards from the outside of the slider 300 towards the access port. The two parts protruding outwards from the outside of the slider 300 respectively form two limiting spaces for assembling the limiting parts. The covering part 1210 cooperates with the limiting parts to close the access port. After closing, the slider 300 is surrounded inside, forming a limit around the slider 300 to prevent the slider 300 from coming out.

[0048] The limiting part can be configured as a limiting block 130 capable of closing the access port. The limiting block 130 is detachably connected to the backrest body 100. The limiting block 130 has a limiting main body 131 that blocks the outside of the slider 300 along the access direction of the slider 300. The limiting main body 131 is detachably arranged at the access port. A number of first reinforcement holes 1310 are provided on the limiting main body 131, and a corresponding number of second reinforcement holes 122 are also provided at the corresponding positions of the U-shaped chute 120. The first reinforcement holes 1310 and the second reinforcement holes 122 are screwed together by a reinforcement bolt 140. After the slider 300 is slidably connected to the L-shaped assembly part and the limiting main body 131 is screwed with the reinforcement bolt 140, the limiting block 130 and the backrest body 100 are fixed more firmly, further improving the stability of the connection between the backrest body 100 and the connecting arm 200.

[0049] To facilitate the user to quickly and conveniently assemble the reinforcement bolt 140, the reinforcement bolt 140 has a convex part 141 that can be exposed outside the first processing hole or the second reinforcement hole 122 after re-assembly. By grasping the convex part 141, the reinforcement bolt 140 can be rotated to complete disassembly and assembly without the aid of other disassembly tools, and the method of assembling the reinforcement bolt 140 is also very convenient and fast.

[0050] Please refer to Figure 5, the limiting block 130 further has a pressing portion 132 connected to the limiting body 131 and capable of pressing against the outer surface of the slider 300. At both ends of the pressing portion 132, there are formed limiting portions 1320 capable of extending into the limiting space along the access direction of the slider 300. The pressing portion 132 can be configured to be connected end to end with the covering portion 1210 to form a frame structure for forming a block around the outer surface of the slider 300 to prevent the slider 300 from detaching from the backrest body 100 in a direction away from the backrest body 100. When the limiting block 130 is installed, after the two sides of the limiting block 130 are slidably assembled in the corresponding L-shaped assembly portions until the limiting portions 1320 are adapted to the limiting space, the covering portion 1210 and the pressing portion 132 form a frame structure capable of pressing the slider 300 therein, not only stably and firmly limiting the slider 300, but also covering the periphery of the slider 300, making the appearance more beautiful.

[0051] The slider 300 has an angle adjustment portion capable of rotatably connecting with the connecting arm 200. The angle adjustment portion can be configured as a pitch angle adjustment portion 310 for adjusting the pitch angle of the backrest body 100 and / or a horizontal angle adjustment portion for adjusting the horizontal angle of the backrest body 100. Hereinafter, the angle adjustment portion of the present invention will be exemplarily described with the pitch angle adjustment portion 310 as a specific example.

[0052] Please refer to Figure 6 , the connecting arm 200 has two connecting wings 2110 arranged horizontally at intervals. A connecting position 2110A for installing the pitch angle adjustment portion 310 is formed between the two connecting wings 2110. For the convenience of assembling the connecting wing 2110 and the pitch angle adjustment portion 310, one of the connecting wings 2110 can be fixedly connected to the connecting arm 200, and the other connecting wing 2110 can be screwed to the connecting arm 200 through a bolt. The pitch angle adjustment portion 310 installed in the connecting position 2110A can rotate around its own axis to adjust the pitch angle of the backrest body 100, and the adjustment position of the pitch angle adjustment portion 310 is locked by the first angle locking mechanism 400. By adjusting the angle between the backrest body 100 and the connecting arm 200 through the pitch angle adjustment portion 310, the different pitch angle reclining requirements of different users can be met.

[0053] The horizontal angle adjustment portion satisfies the requirement that the backrest body 100 can be horizontally adjusted. The structure of the horizontal angle adjustment portion can refer to the structure of the pitch angle adjustment portion 310. Rotate the pitch angle adjustment portion 310 by 90 degrees to make it satisfy horizontal rotation and angle adjustment. When the horizontal angle adjustment portion and the pitch angle adjustment portion 310 are connected in series through a connecting mechanism, both pitch and horizontal adjustment can be achieved, and the angle adjustment is more comprehensive, flexible and practical.

[0054] Please refer to Figure 7 andFigure 8 The first angle locking mechanism 400 includes first angle locking parts 410 symmetrically arranged on both sides of the pitch angle adjusting part 310, second angle locking parts 420 arranged on the connecting wing 2110 and connected to the first angle locking parts 410 in one-to-one correspondence, two symmetrically and spaced angle locking knobs 430 movably connected within the first angle locking parts 410 and the second angle locking parts 420, and a return spring 440 arranged between the two angle locking knobs 430. Press the two angle locking knobs 430 towards the direction of approaching each other, and the angle locking knobs 430 move towards the direction close to the first angle locking part 410 and separate from the second angle locking part 420. Release the angle locking knobs 430, and the return spring 440 drives the two angle locking knobs 430 to return and lock the positions of the first angle locking part 410 and the second angle locking part 420. When adjusting the pitch angle, it is simple and easy to operate, achieving rapid angle adjustment.

[0055] Please refer to Figure 9 The first angle locking part 410 includes a first locking cavity 411 arranged on the side wall of the pitch angle adjusting part 310, several first tooth parts 412 arranged at intervals around the inner peripheral surface of the first locking cavity 411, and a guiding groove 413 coaxially arranged with the first locking cavity 411 and surrounding the first locking cavity 411. The two symmetrically arranged first locking cavities 411 are communicated through a first through hole 414, and the inner diameter of the first through hole 414 is smaller than the inner diameter of the first locking cavity 411. In order to save materials of the pitch angle adjusting part 310, the depth of the first locking cavity 411 is relatively deep, and several reinforcing ribs 4130 are arranged in the first locking cavity 411 to ensure the strength of the pitch angle adjusting part 310.

[0056] Please refer to Figure 10 The second angle locking part 420 includes a second locking cavity 421 arranged on the inner wall of the connecting wing 2110, several second tooth parts 422 arranged at intervals around the inner peripheral surface of the second locking cavity 421 and corresponding to the first tooth parts 412, an annular flange 423 protruding from the inner wall of the connecting wing 2110 in a direction away from the inner wall of the connecting wing 2110 and capable of having a clearance fit with the guiding groove 413, and a second through hole 424 arranged on the outer wall of the connecting wing 2110 and penetrating inward towards the second locking cavity 421. The inner diameter of the second through hole 424 is smaller than the inner diameter of the second locking cavity 421.

[0057] The angle locking knob 430 includes a knob body 431 with a mounting port at one end, and a plurality of third tooth portions 432 arranged at intervals around the outer periphery of the knob body 431. The blind end of the knob body 431 is exposed outside the connecting wing 2110, and the other relatively open end enters the second through hole 424, so that the third tooth portions 432 are engaged with the first tooth portion 412 and the second tooth portion 422, thereby locking the pitch angle adjusting portion 310 to the connecting wing 2110. The two ends of the return spring 440 are respectively located in the inner cavities of the two knob bodies 431 after passing through the first through hole 414.

[0058] With the above first angle locking mechanism 400, when pressing the blind ends of the two knob bodies 431, a plurality of third tooth portions 432 of the two knob bodies 431 move towards the direction close to the first tooth portion 412, and the third tooth portions 432 enter the gaps of the first tooth portion 412 one by one. In this state, the return spring 440 is compressed, and the third tooth portions 432 are separated from the second tooth portion 422, so that the pitch angle adjusting portion 310 can be rotated. When rotating the pitch angle adjusting portion 310, the annular flange 423 rotates along the guiding groove 413 in the guiding groove 413 to guide the rotation direction. After releasing the pressing on the angle locking knob 430, the return spring 440 returns to its original position, driving the angle locking knob 430 to return to its original position. After the angle locking knob 430 returns to its original position, the third tooth portions 432 in the angle locking knob 430 are engaged with the first tooth portion 412 and the second tooth portion 422, realizing the locking of the pitch angle adjusting portion 310 to the connecting arm 200. By connecting the two angle locking knobs 430 to the connecting arm 200, the connection strength at the connection position between the connecting arm 200 and the pitch angle adjusting portion 310 is enhanced. The engagement between the third tooth portions 432 and the first tooth portion 412 and the second tooth portion 422 is tighter and will not easily slip off, improving the connection reliability at the connection position.

[0059] The connecting arm 200 includes a telescopic arm 210 connected to the pitch angle adjusting portion 310 and an arm main body 220 that can movably connect the telescopic arm 210 therein. Please refer to Figure 11 , the telescopic arm 210 includes an arm head 211 and an arm rod 212 bolted to the arm head 211. When the telescopic arm 210 is in the original non-telescopic state, the arm head 211 can be exposed outside the outer end of the arm main body 220. The connecting wing 2110 is provided on the arm head 211 and is connected to the pitch angle adjusting portion 310. The telescopic arm 210 can reciprocate inside the arm main body 220, and a telescopic locking mechanism 500 is connected to the arm main body 220 for locking the position of the telescopic arm 210. After the telescopic arm 210 is movably connected inside the arm main body 220, the length of the connecting arm 200 can be adjusted according to the actual situation of the user, providing an adaptable length support for the user.

[0060] One end of the telescopic arm 210 away from the backrest body 100 is provided with a first mounting groove for mounting an elastic member, that is, the first mounting groove is opened at the end face of the arm rod 212 installed in the arm main body 220, and a second mounting groove connected to the elastic member is opened at a position corresponding to the elastic member inside the arm main body 220. When the telescopic arm 212 is in the original non-telescopic state, the elastic member is in a stretched state in the arm main body to store elastic force. When the locking of the telescopic locking mechanism 500 is unlocked and the arm rod 212 is not limited and can move, the elastic member can drive the telescopic arm to move away from the arm main body. After the arm rod 212 returns to its position, the elastic member is in a stretched state again. The advantage of such a design is that after unlocking the locking of the telescopic locking mechanism 500, the arm rod 212 can move automatically, and the length can be adjusted automatically and quickly, making it more convenient to use.

[0061] The elastic member is preferably a constant-force spring. One end of the constant-force spring has a T-shaped clamping portion. The first mounting groove is an arc groove adapted to the outer peripheral surface of the constant-force spring, and the shape of the second mounting groove is adapted to the shape of the T-shaped clamping portion and is connected to the T-shaped clamping portion in cooperation. The constant-force spring is made of a stainless steel steel strip. The high-strength steel strip is shaped by a machine into a plurality of concentric circles with the same diameter from the inside to the outside. When the arm rod 212 is in the original non-telescopic state, the end provided with the first mounting groove is at a position away from the arm head 211. In this state, the constant-force spring is stretched into a straight line, and at this time, the constant-force spring stores elastic force. After pressing the telescopic locking mechanism 500 to unlock the locking of the arm rod 212, the straightened part of the constant-force spring can return to the previous circular shape and generate a pulling force to drive the arm rod 212 to move away from the arm main body 220, and the arm rod 212 can automatically move to the maximum telescopic stroke under the drive of the constant-force spring, and then choose whether to shorten the arm rod 212 according to actual needs. After unlocking the locking of the arm rod 212, the arm rod 212 can automatically adjust its length, which is convenient and fast to adjust.

[0062] The elastic member can also be other elastic components such as a tension spring. When installing elastic members with other structures, the positions of the telescopic arm 210 and the arm main body 220 for installing the elastic member can be adjusted adaptively according to the structure of the elastic member.

[0063] Please refer to Figure 12 , the telescopic locking mechanism 500 includes a first length adjustment portion provided on the arm main body 220, a second length adjustment portion correspondingly provided on the arm rod 212, a length locking mechanism installed on the first length adjustment portion and the second length adjustment portion for locking the adjustment position of the second length adjustment portion, and a first return spring 540. Pressing the length locking mechanism unlocks the telescopic arm 210 and the arm main body 220, and the telescopic arm 210 can reciprocate along the inner cavity of the arm main body 220 to adjust the length. Releasing the pressing on the length locking mechanism, the first return spring 540 drives the length locking mechanism to return to its position to lock the movable arm rod 212.

[0064] Among them, the first length adjustment part includes an annular protrusion 510A protruding from the outer surface of the arm main body 220 in a direction away from the outer surface, a first fitting cavity 510B recessed from the top surface of the annular protrusion 510A towards the inside of the arm main body 220, a second fitting cavity communicating with the first fitting cavity 510B and having an inner diameter smaller than that of the first fitting cavity 510B, a third fitting cavity 510C located at the lower end of the second fitting cavity and having an inner diameter smaller than that of the second fitting cavity, a fourth fitting cavity provided at one end of the arm main body 220 away from the annular protrusion 510A, and a stepped groove 510D communicating with the fourth fitting cavity and located at the bottom surface of the arm main body 220.

[0065] The second length adjustment part includes two telescopic fitting parts 520 provided on the arm rod 212 and capable of vertically penetrating the arm rod 212. Please refer to Figure 11 , in the top-down orthographic projection plane, the two telescopic fitting parts 520 overlap. All the telescopic fitting parts 520 include a plurality of first fitting spaces 520A arranged at equal intervals along the length direction of the arm rod 212, and a plurality of second fitting spaces 520B. Each two adjacent first fitting spaces 520A are communicated through a second fitting space 520B, and the gap width of the second fitting space 520B is smaller than the gap width of the first fitting space 520A. The positions of the first fitting spaces 520A and the second fitting spaces 520B can correspond to the positions of the first fitting cavity 510B, the second fitting cavity, the third fitting cavity 510C, the fourth fitting cavity, and the stepped groove 510D.

[0066] The length locking mechanism includes a locking button 530A partially installed in the annular protrusion 510A, a spring sleeve section 530B provided at the lower end of the locking button 530A and having an outer diameter smaller than that of the locking button 530A, a first mating section 530C provided at the lower end of the spring sleeve section 530B, a first limiting section 530D provided at the lower end of the first mating section 530C and having an outer diameter larger than that of the first mating section 530C, a second mating section 530E provided at the lower end of the first limiting section 530D and having the same shape and outer diameter as the first mating section 530C, a second limiting section 530F provided at the lower end of the second mating section 530E and having the same shape and outer diameter as the first limiting section 530D, and a tail section 530H provided at the lower end of the second limiting section 530F. The spring sleeve section 530B is sleeved in the first return spring 540 and located at the lower end of the locking button 530A, and the first return spring 540 is partially installed in the third mating cavity 510C. In the state of locking the telescopic arm 210, the tail section 530H is located in the stepped groove 510D, and the first limiting section 530D and the second limiting section 530F are respectively located in two first mating spaces 520A at the upper end and the lower end of the arm rod 212 to limit the movement of the arm rod 212. In this state, the spring sleeve section 530B adjacent to the locking button 530A is located in the second mating cavity, the first mating section 530C is located in the third mating cavity 510C, the upper part of the second limiting section 530F is accommodated in the first mating space 520A, and the lower part is accommodated in the fourth mating cavity, and the first mating section 530C and the second mating section 530E can reciprocate in the first mating space 520A and the second mating space 520B.

[0067] When the locking button 530A is pressed, the first return spring 540 is in a compressed state, the first limiting section 530D and the second limiting section 530F can be disengaged from the corresponding first mating spaces 520A, and the tail section 530H moves in a direction away from the stepped groove 510D until the first mating section 530C and the second mating section 530E with smaller outer diameters enter the corresponding first mating spaces 520A. Since the first mating section 530C and the second mating section 530E can also move in the second mating space 520B, when the user operates the telescopic arm 210 to reciprocate in the arm main body 220, the first mating section 530C and the second mating section 530E can smoothly reciprocate in the corresponding telescopic mating parts 520, and finally the telescopic adjustment of the telescopic arm 210 is realized. After releasing the pressing of the locking button 530A, the first return spring 540 returns to drive the first limiting section 530D and the second limiting section 530F to return to the corresponding first mating spaces 520A to restore the locking of the position of the telescopic arm 210. The user can adjust the length of the connecting arm 200 according to different length usage requirements. Moreover, during the process of adjusting the telescopic length of the telescopic arm 210, only by pressing the locking button 530A, the telescopic arm 210 can automatically adjust the length or manually adjust the length, and the adjustment is convenient and practical.

[0068] Please continue reading Figure 1 and Figure 14 The preferred structure of the arm body 220 is as follows: the end of the arm body 220 away from the arm head 211 has two symmetrically arranged branch arms 221, each of the branch arms 221 is provided with a connecting portion 2210, and the connecting portion 2210 is provided with a plurality of material-saving grooves 2210B recessed toward the inner direction of the branch arm 221, and the material-saving grooves 2210B are used to save production materials and also have the function of reducing deadweight. The connecting portion 2210 can connect the connecting arm 200 to a fixed object through a switching mechanism, and the fixed object preferably adopts a connecting frame, and the connecting frame has connecting plates 700 corresponding to the position of the connecting portion 2210, and the two connecting plates 700 are connected by a connecting main board. The connecting main board is used to be detachably connected to the frame of a motorcycle or electric vehicle, so that the backrest device can be installed on a two-wheeled vehicle driven by a user.

[0069] See also Figure 13 In a preferred embodiment, the adapter mechanism is connected between the branch arm 221 and the fixed object, and the branch arm 221 can rotate around the rotation axis of the adapter mechanism. The adapter mechanism has an adapter shaft 600, one end of which is inserted into the position of the connecting plate 700. The branch arm 221 is rotatably connected to the connecting plate 700 through the adapter shaft 600 and can rotate around the axis of the adapter shaft 600. The connecting portion 2210 and the connecting plate 700 are both provided with an axial hole for the adapter shaft 600 to pass through. After the adapter shaft 600 is rotatably connected in the axial hole, the position of the adapter shaft 600 is limited by a limit nut 610 threaded with the adapter shaft 600 to prevent the adapter shaft 600 from falling off. In order to make the appearance more beautiful, the limit nut 610 is distributed on the inner side of the branch arm 221. The adapter shaft 600 is also connected to a cover 620 to cover the connecting plate 700 and the connecting portion 2210. The connecting plate 700 is located between the cover 620 and the connecting portion 2210. The appearance of the connecting position is more beautiful, and the cover 620 can protect the angle locking mechanism and the elastic mechanism 900 at the corresponding position.

[0070] In a preferred embodiment, an angle locking mechanism is provided at the branch arm 221 and / or the fixed object (connection plate 700) for locking the backrest so that the backrest is fixed in the current locked state. The angle locking mechanism capable of locking the angle between the connecting arm 200 and the fixed object is defined as the second angle locking mechanism. The second angle locking mechanism includes a plurality of locking holes 710 and a locking member 800. The plurality of locking holes 710 can be configured to be distributed in a circular or arc shape around the center with the rotation axis as the center at the fixed object or the branch arm 221. In one embodiment, the plurality of locking holes 710 are distributed on the connection plate 700. The locking member 800 is provided at the backrest or the fixed object and can extend into and withdraw from the locking holes 710 along the rotation axis direction. The second angle locking mechanism can be used to adjust the pitching angle of the connecting arm 200, so that the backrest device has more and more flexible functions. In addition to this structure, a parallel manner or the like can also be adopted to support the corresponding upper claim.

[0071] Specifically, in one embodiment, a through hole 2210A for installing the locking member 800 is opened in the connecting portion 2210. The through hole 2210A is arranged along the rotation axis direction. Please continue to refer to Figure 13 , the locking member 800 includes a locking pin 810 movably inserted into the through hole 2210A, a third return spring 820 arranged in the through hole 2210A and capable of pushing the locking pin 810 retracted into the through hole 2210A towards the locking hole 710, and a locking handle 830. The locking handle 830 is arranged outside the branch arm 221 on the side away from the locking hole 710 and is connected to the end of the locking pin 810 away from the locking hole 710. The fixed object includes two connection plates 700 arranged at intervals. Please refer to Figure 15, a plurality of locking holes 710 are provided on each connecting plate 700. Connecting parts 2210 corresponding to the positions of the two connecting plates 700 are respectively provided on the branch arms 221 of the backrest. A through hole 2210A for connecting a locking member 800 is provided on each connecting part 2210. The locking member 800 is rotatably connected to the through hole 2210A such that the locking handle 830 is located outside the branch arm 221. The locking pin 810 includes a pin head 811 connected to the connecting plate 700, a pin rod 812 fixedly connected to the pin head 811, and a support rod 813 perpendicularly connected to the pin rod 812. The pin rod 812 is sleeved in the third return spring 820. The locking handle 830 is pivotally connected to the support rod 813 and rotates around the support rod 813. When the locking handle 830 is perpendicular to the branch arm 221, the locking pin 810 can lock the connecting plate 700. When the locking handle 830 rotates away from the through hole 2210A, the locking pin 810 can disengage from the connecting plate 700. The position of the locking connection arm 200 is locked by rotating the locking handle 830. The operation method is simple and fast, easy to operate, and can quickly adjust the angle of the connection arm 200. In addition to this structure, a parallel manner or the like can also be adopted to support the corresponding upper claims.

[0072] Please refer to Figure 16 , the locking handle 830 includes a handle 831, a handle head 832 fixedly connected to the handle 831, and a receiving notch 833 provided on the handle head 832 for receiving the pin rod 812. The outer wall of the handle head 832 has two opposite smooth cut surfaces 8320. The receiving notch 833 is distributed between the two smooth cut surfaces 8320. An installation hole for installing the support rod 813 is provided on each smooth cut surface 8320, with one end penetrating into the receiving notch 833 and the other end penetrating out of the smooth cut surface 8320. The installation hole can rotate around the support rod 813. The handle head 832 has a structure with a smaller outer diameter at both ends and a larger middle part, similar to an oval shape. A line segment ZA is horizontally extended from the axis of the installation hole, and a line segment ZB is extended from the axis of the installation hole to the end face away from the handle 831. The length of the line segment ZA is greater than the length of the line segment ZB. Therefore, after the locking pin 810 is installed in the through hole 2210A, the end of the handle head 832 away from the handle 831 abuts against the inner side of the branch arm 221. When the locking handle 830 is rotated along the support rod 813, the design that the length of the line segment ZA is greater than the length of the line segment ZB can prevent interference with the rotation of the locking handle 830 and can also smoothly operate the locking handle 830 to withdraw the pin head 811 from the locking hole 710. The connecting plate 700 and the branch arm 221 are not locked, and the angle adjustment can be smoothly completed. When the pin head 811 is withdrawn, the third return spring 820 is in a compressed state. At this time, the locking handle 830 is rotated to a state perpendicular to the branch arm 221, and the reset of the third return spring 820 can drive the pin head 811 to move into the locking hole 710 until the position of the locking hole 710 is locked. The operation is simple and convenient.

[0073] Grip the locking handle 830, and the entire lock 800 can be operated to rotate around the through hole 2210A. Therefore, the rotation direction of the locking handle 830 can also be adjusted according to the actual operation situation.

[0074] An elastic mechanism 900 is also provided to indicate the successful completion of the angle adjustment. The elastic mechanism 900 is arranged at the backrest or a fixed object. When the backrest is rotated and adjusted, the elastic mechanism 900 is separated from the fixed object or the backrest. In one embodiment, the elastic mechanism 900 is arranged at the position of the connecting part 2210. After the backrest is adjusted to the required angle, the elastic mechanism 900 returns to its original position to indicate the completion of the angle adjustment. To facilitate the user to clearly know the specific angle being adjusted, the included angle between every two adjacent locking holes 710 is preferably 45°. The radian and spacing between the elastic mechanism 900 and the lock 800 are adapted to the radian and spacing of any two adjacent locking holes 710. When the lock 800 is inserted into one of the locking holes 710, specifically, the pin head 811 is inserted into one of the locking holes 710, the elastic mechanism 900 abuts against another adjacent locking hole 710 and is limited by this another locking hole 710. When the branch arm 221 is rotated forward or backward, the elastic mechanism 900 can retract and separate from the connecting plate 700. After the adjustment is in place, the elastic mechanism 900 is positioned within the locking hole 710 to indicate the completion of the adjustment. By indicating once or multiple times, the user can clearly master the specific angle being adjusted, accurately adjust to the required angle, and reduce the occurrence of situations where the adjustment is not in place or over-adjusted.

[0075] Please refer to Figure 17 , the elastic mechanism 900 includes an embedding part 910 embedded in the backrest or a fixed object, a second return spring 920 installed in the inner cavity of the embedding part 910, and a positioning bead 930 that abuts against the second return spring 920 and is partially exposed outside the embedding part 910. In one embodiment, the elastic mechanism 900 is arranged at the position of the connecting part 2210. When the lock 800 is inserted into one of the locking holes 710, when the spherical surface of the positioning bead 930 enters another adjacent locking hole 710, it collides with the hole edge of the another adjacent locking hole 710 to indicate that the backrest is fixed at the current angle. During the process of adjusting the angle of the connecting arm 200, while the connecting arm 200 rotates forward or backward, the positioning bead 930 will be adapted to cooperate with the corresponding locking hole 710 to form a positioning. Each time the angle adjustment is completed, the positioning bead 930 will collide with the locking hole 710. The adjustment gears are clear and obvious, and each gear has an obvious tactile hint, which is convenient for grasping the rotation angle of the branch arm 221 and the adjustment is accurate and in place. In addition to this structure, a parallel arrangement or the like can also be adopted to support the corresponding upper claim.

[0076] The quick-release backrest device: First, the backrest body 100 can be disassembled from the connecting arm 200, which is convenient for replacing the backrest body 100 when it is worn or out of style. Moreover, in the way of sliding-in assembly, when disassembling and replacing, the backrest body 100 and the slider 300 can be quickly positioned, and the whole replacement and assembly process is simple, fast and easy to operate. Second, the periphery of the slider 300 is pressed by the covering part 1210 and the pressing part 132 to form a stable and firm fixing structure, which increases the support strength at the connection after limiting. Third, the first angle adjustment mechanism can adjust the pitching angle of the backrest body 100 according to the actual situation of the user, so that the use surface of the backrest body 100 can support people more fittingly. Moreover, after adjusting the angle of the pitching angle adjustment part 310, it is locked by two knob bodies 431. The third tooth parts 432 on the two knob bodies 431 can mesh more tightly with the first tooth part 412 and the second tooth part 422, improving the locking effect and being more firm and reliable when locking the angle. Fourth, the connecting arm 200 can also be adjusted in length. According to the different lengths required by different users for the backrest body 100, the telescopic arm 210 reciprocates in the arm main body 220, and then through the telescopic locking mechanism 500, the position of the telescopic arm 210 is locked to complete the adjustment of the length of the connecting arm 200. Fifth, the connecting arm 200 is connected to the two-wheeler through a connecting frame. By rotating the locking handle 830, the pin head 811 can withdraw from the locking hole 710, and by rotating the connecting arm 200, the angle can be adjusted. After the third return spring 820 drives the pin head 811 to return to its position, the position of the locking connecting plate 700 is locked, and the connecting arm 200 can be adjusted in pitching angle as needed. Sixth, during the process of rotating and adjusting the connecting arm 200, the positioning beads 930 in the elastic mechanism 900 can enter and exit the locking hole 710, and collide with the edge of the locking hole 710 during the positioning process. The adjustment gears are clear and obvious, and there is an obvious adjustment feel. After the distances between each locking hole 710 are equal, through the number of positioning times of the elastic mechanism 900, the specific adjustment angle can be known during each adjustment process, avoiding the situation of under-adjustment or over-adjustment.

[0077] The above is only the implementation mode of the present utility model, and does not limit the patent scope of the present utility model accordingly. Any equivalent structure made by using the specification and drawings of the present utility model, directly or indirectly applied in other related technical fields, is similarly within the patent protection scope of the present utility model.

Claims

1. A quick-release backrest device, characterized in that: The invention comprises a backrest, which comprises a backrest body and a connecting arm detachably connected to the backrest body, the backrest body is provided with an assembly position having a sliding entrance and a limiting portion, the connecting arm is provided with a sliding block which can slide into the assembly position along the sliding entrance at a position corresponding to the assembly position, and when the sliding block is assembled in the assembly position, the limiting portion is used to limit the sliding block in the assembly position.

2. The quick-release backrest device according to claim 1, characterized in that: The assembly position includes a U-shaped slide groove recessed toward the inner direction of the backrest body, the opening of the U-shaped slide groove forms a slide entrance for the slider to freely enter and exit, and a side wall of the U-shaped slide groove is formed with a stopper for preventing the slider from detaching from the backrest body in a direction away from the backrest body; The limiting portion is configured as a limiting block capable of closing the sliding entrance.

3. The quick-release backrest device according to claim 2, characterized in that: The enclosure has a covering portion that can partially cover the U-shaped slide groove, and the bottom surface of the covering portion and the side wall of the U-shaped slide groove can form an L-shaped assembly portion that is slidably connected to the slider. When the slider is assembled in the U-shaped slide groove, the covering portion can be pressed on the outer surface of the slider.

4. The quick-release backrest device according to claim 3, characterized in that: The limiting block has a limiting body which is blocked at the outer side of the sliding block along the in and out direction of the sliding block, and the limiting body is detachably arranged at the sliding entrance.

5. The quick-release backrest device according to claim 4, characterized in that: The limit block also has a holding portion connected to the limit body and capable of pressing on the outer surface of the slider. The holding portion can be configured to be connected end to end with the covering portion to form a frame-shaped structure, which is used to form a barrier around the outer surface of the slider to prevent the slider from detaching from the backrest body in a direction away from the backrest body.

6. The quick-release backrest device according to claim 5, characterized in that: The length of the two L-shaped assembly parts on the U-shaped chute, which are equal to the entry and exit direction of the slider, is greater than the length of the slider in this direction. When the slider slides into the bottom of the U-shaped chute, the two L-shaped assembly parts protrude outward from the slider in the direction of the sliding entrance, and the two parts protruding outward from the slider respectively form two limiting spaces; The two ends of the pressing portion are formed with limiting portions that can extend into the limiting space along the entry and exit direction of the slider; The limiting body is provided with a plurality of first reinforcement holes, and a plurality of second reinforcement holes corresponding to each other are also provided at corresponding positions of the U-shaped slide groove, and the first reinforcement holes and the second reinforcement holes are screwed together by reinforcement bolts.

7. The quick-release backrest device according to any one of claims 1 to 6, characterized in that: The sliding block has an angle adjustment portion which can be rotatably connected to the connecting arm.

8. The quick-release backrest device according to claim 7, characterized in that: The angle adjustment portion is configured as a pitch angle adjustment portion for adjusting the pitch angle of the backrest body and / or a horizontal angle adjustment portion for adjusting the horizontal angle of the backrest body.

9. The quick-release backrest device according to claim 8, characterized in that: The connecting arm has two connecting wings arranged horizontally at intervals, and a connecting position for installing the pitch angle adjustment part is formed between the two connecting wings. The pitch angle adjustment part installed in the connecting position can rotate around its own axis to adjust the pitch angle of the backrest body, and the adjustment position of the pitch angle adjustment part is locked by a first angle locking mechanism.

10. The quick-release backrest device according to claim 9, characterized in that: The first angle locking mechanism comprises first angle locking parts symmetrically arranged on both sides of the pitch angle adjusting part, second angle locking parts provided on the connecting wing and connected to the first angle locking parts in a one-to-one correspondence, two angle locking knobs symmetrically arranged at intervals and movably connected in the first angle locking part and the second angle locking part, and a return spring provided between the two angle locking knobs, the two angle locking knobs are pressed in a direction approaching each other, the angle locking knobs are moved in a direction approaching the first angle locking part and separated from the second angle locking part, the angle locking knobs are loosened, and the return spring drives the two angle locking knobs to return and lock the positions of the first angle locking part and the second angle locking part; The first angle locking portion comprises a first locking cavity provided on the side wall of the pitch angle adjusting portion, a plurality of first teeth arranged at intervals around the inner circumference of the first locking cavity, and a guide groove arranged coaxially with the first locking cavity and surrounding the first locking cavity, two symmetrically arranged first locking cavities are connected by a first through hole, and the inner diameter of the first through hole is smaller than the inner diameter of the first locking cavity; The second angle locking portion comprises a second locking cavity provided on the inner wall of the connecting wing, a plurality of second teeth arranged at intervals around the inner circumference of the second locking cavity and on the first teeth, an annular flange protruding from the inner wall of the connecting wing away from the inner wall of the connecting wing and capable of gap-matching with the guide groove, and a second through hole provided on the outer wall of the connecting wing and penetrating inwardly in the direction of the second locking cavity, wherein the inner diameter of the second through hole is smaller than the inner diameter of the second locking cavity; The angle locking knob comprises a knob body having a mounting opening at one end, and a plurality of third teeth arranged at intervals around the outer periphery of the knob body, the blind end of the knob body is exposed outside the connecting wing, and the other relatively open end thereof enters the second through hole so that the third teeth mesh with the first teeth and the second teeth, thereby locking the pitch angle adjustment part and the connecting wing, and the two ends of the return spring after passing through the first through hole are respectively located in the inner cavities of the two knob bodies; When the blind ends of the two knob bodies are pressed, the several third teeth of the two knob bodies move toward the first teeth until the third teeth enter the gaps of the first teeth one by one, so that the return spring is compressed and the third teeth are separated from the second teeth; the pressure on the angle locking knob is released, and the return spring returns to drive the angle locking knob to return, and the third teeth return to engage with the first teeth and the second teeth, so as to lock the pitch angle adjustment part with the connecting arm.

11. The quick-release backrest device according to claim 1, characterized in that: The connecting arm includes a telescopic arm and an arm body in which the telescopic arm is movably installed, the telescopic arm can reciprocate inside the arm body, a first mounting groove for mounting an elastic member is provided at one end of the telescopic arm away from the backrest body, and a second mounting groove connected to the elastic member is provided at a position corresponding to the elastic member inside the arm body, a telescopic locking mechanism for locking the position of the telescopic arm is connected to the arm body; when the telescopic arm is in an original un-extended state, the elastic member is in a stretched state to store elastic force, and when the telescopic locking mechanism is unlocked, the elastic member can drive the telescopic arm to move in a direction away from the arm body.

12. The quick-release backrest device according to claim 11, characterized in that: The elastic member is a constant force mainspring with a T-shaped clamping portion at one end, the first mounting groove is an arc groove matched with the outer circumferential surface of the constant force mainspring, and the second mounting groove is cooperatively connected with the T-shaped clamping portion.

Images