Telescopic folding chair

Abstract

The telescopic folding chair comprises an upper mounting seat, a lower mounting seat and a cushion, a plurality of supporting legs are hinged to the periphery of the bottom of the upper mounting seat, a plurality of telescopic arm pipe sets are hinged to the periphery of the top of the lower mounting seat, the cushion is mounted on the telescopic arm pipe sets, and a plurality of inclined guide holes are formed in the lower mounting seat; the supporting legs are arranged in the inclined guide holes in a penetrating mode, a rotary limiting mechanism is rotationally arranged on the upper mounting base, a receding hole is formed in the lower mounting base, a limiting head is arranged at the bottom of the rotary limiting mechanism, a limiting part is arranged on the periphery, corresponding to the receding hole, of the bottom wall of the lower mounting base, and the rotary limiting mechanism rotates to control the limiting head to be movably matched with the limiting part in a limiting mode. In the stretching state, the limiting head penetrates out of the receding hole and is rotationally limited with the limiting part, the upper mounting base and the lower mounting base abut against and are locked up and down, in the contracting state, the limiting head and the limiting part relieve rotation limiting and retreat from the receding hole, and the upper mounting base and the lower mounting base are separated from each other. The device is simple in structure and rapid and convenient to unfold and fold.

Description

Technical Field

[0001] The invention relates to the technical field of telescopic folding chairs, and in particular to a telescopic folding chair. Background Art

[0002] The existing folding structure and folding chair for folding chairs with convenient operation, such as the folding structure disclosed in publication number CN111588211A, need to rotate the rotating part counterclockwise or clockwise when unfolding or folding, and then drive the rotating part, linkage part, installation frame, legs, telescopic tubes and other components to move in sequence, so that all telescopic tubes can be unfolded for use or gathered for storage. The technical solution has a relatively complex structure, the unfolding and retracting operations are not fast and convenient enough, and the stability is insufficient, which affects the user experience. Summary of the invention

[0003] The present invention aims to provide a telescopic folding chair to solve the above-mentioned technical problems.

[0004] To achieve the above-mentioned purpose, the technical scheme of the present invention is as follows: a telescopic folding chair comprises a mounting seat assembly and a seat cushion, the mounting seat assembly comprises an upper mounting seat and a lower mounting seat corresponding to each other up and down, a plurality of supporting legs are hingedly connected to the periphery of the bottom of the upper mounting seat, a plurality of telescopic arm tube groups are hingedly connected to the periphery of the top of the lower mounting seat, the seat cushion is mounted on the plurality of telescopic arm tube groups, a plurality of inclined guide holes are opened in the circumferential direction of the lower mounting seat, the supporting legs are penetrated and arranged in the inclined guide holes, a rotation limiting mechanism is rotatably arranged on the upper mounting seat, a yielding hole is opened on the lower mounting seat, the bottom of the rotation limiting mechanism is a limiting head, the periphery of the yielding hole of the lower mounting seat is a limiting part, the rotation limiting mechanism rotates to control the limiting head and the limiting part to cooperate with the movable limiting part, in the extended state, the limiting head penetrates the yielding hole and is rotationally limited with the limiting part, the upper mounting seat and the lower mounting seat are abutted and locked up and down, in the contracted state, the limiting head and the limiting part release the rotation limit and exit the yielding hole, and the upper mounting seat and the lower mounting seat are separated from each other.

[0005] Preferably, the clearance hole is a special-shaped clearance hole, the limit head is a special-shaped clearance head, the shape and size of the minimum cross-section of the clearance hole is the same as the shape and size of the maximum cross-section of the limit head, in the extended state, the limit head passes through the clearance hole and is staggered with the clearance hole to achieve rotational limit of the limit head and the limit part, the upper mounting seat and the lower mounting seat are abutted and locked up and down, in the contracted state, the limit head and the clearance hole are aligned and withdrawn from the clearance hole to achieve the release of rotational limit of the limit head and the limit part, and the upper mounting seat and the lower mounting seat are separated from each other.

[0006] Preferably, the rotation limit mechanism includes a switch cover and a center rod, the top end of the center rod is connected to the switch cover, the limit head is located at the bottom end of the center rod, the switch cover is rotatably set on the top of the upper mounting seat, and a mounting through hole is opened in the center of the upper mounting seat, and the center rod passes through the mounting through hole.

[0007] Preferably, the rotation limit mechanism also includes a special-shaped connecting block and a screw locking piece, a first threaded hole is provided in the center of the special-shaped connecting block, a second threaded hole is provided at the top end of the center rod, a special-shaped positioning hole is provided in the center of the switch cover, the special-shaped connecting block is limitedly installed on the special-shaped positioning hole, and the screw locking piece is threadedly connected to the first threaded hole and the second threaded hole in sequence, thereby fixing the center rod to the switch cover, and an expansion blocking portion is formed on one side of the center rod close to the limit head, the diameter of the expansion blocking portion is larger than the mounting through hole, and the top wall of the expansion blocking portion is abutted against the bottom wall of the upper mounting seat.

[0008] Preferably, a sliding groove, a first positioning groove and a second positioning groove are provided on the bottom side of the switch rotary cover, and a sliding block and an elastic limiting member are provided on the top wall of the upper mounting seat. The sliding block and the sliding groove are correspondingly slidably matched, and the elastic limiting member is elastically limitedly matched with the first positioning groove and the second positioning groove respectively to realize the active switching between the extended state and the contracted state.

[0009] Preferably, a foot pad is installed at the bottom end of the supporting leg, and a switch mark is provided on the surface of the switch rotary cover.

[0010] Preferably, it also includes a protective bottom cover installed at the bottom of the lower mounting seat, and a metal plate is installed at the limiting portion.

[0011] Preferably, the telescopic arm tube group includes an outer tube and an inner tube slidably and telescopically arranged in the outer tube, the inner tube is provided with an elastic conical component and a push rod, the elastic conical component is elastically and telescopically arranged at the bottom of the inner tube, a limiting tube sleeve is provided at the top end of the outer tube, an annular groove is formed on the inner wall of the limiting tube sleeve, an accommodating hole is opened at the bottom of the inner tube corresponding to the position of the elastic conical component, a rigid sphere is arranged in the accommodating hole, and the push rod is used to control the elastic conical component to perform telescopic movement in the inner tube, thereby realizing the movable limiting cooperation between the rigid sphere and the annular groove.

[0012] Preferably, the elastic conical component includes an inner rod bushing, a compression spring and a conical part. The inner rod bushing is sleeved on the outer bottom of the inner tube. The inner rod bushing is provided with a clearance hole. The conical part includes a conical head and a center axis. The center axis passes through the clearance hole. The compression spring is sleeved outside the center axis, and the two ends of the compression spring are respectively abutted against the inner bottom wall of the inner rod bushing and the conical head. The conical head gradually decreases from the center axis toward the push rod.

[0013] Preferably, it also includes a switch sliding sleeve arranged outside the inner tube, the inner tube is also provided with a sliding hole, a sliding rod is provided on the top of the push rod, and the sliding rod protrudes out of the sliding hole and is connected with the switch sliding sleeve.

[0014] The present invention has the following beneficial effects:

[0015] The present invention comprises a mounting seat assembly and a seat cushion, wherein the mounting seat assembly comprises an upper mounting seat and a lower mounting seat which are matched with each other up and down, a plurality of supporting legs are hingedly connected to the periphery of the bottom of the upper mounting seat, a plurality of telescopic arm tube groups are hingedly connected to the periphery of the top of the lower mounting seat, the seat cushion is mounted on the plurality of telescopic arm tube groups, a plurality of inclined guide holes are opened in the circumferential direction of the lower mounting seat, the supporting legs are penetrated and arranged in the inclined guide holes, a rotation limiting mechanism is rotatably arranged on the upper mounting seat, a clearance hole is opened on the lower mounting seat, the bottom of the rotation limiting mechanism is a limiting head, and the periphery of the corresponding clearance hole of the lower mounting seat is a limiting The rotation limit mechanism rotates to control the limit head and the limit part to cooperate with the movable limit. In the extended state, the limit head passes through the yield hole and is rotationally limited with the limit part, and the upper mounting seat and the lower mounting seat are abutted and locked up and down. In the retracted state, the limit head and the limit part release the rotation limit and exit the yield hole, and the upper mounting seat and the lower mounting seat are separated from each other. The structure of the present invention is simple and easy to operate, and can be quickly unfolded and retracted and folded. It has high stability, so that it can be used safely and quickly by users, ensuring the user experience. At the same time, it occupies a small space and is easy to store and carry. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram of an embodiment of the present invention in a stretched state;

[0017] Figure 2 is a schematic diagram of an embodiment of the present invention in a contracted state;

[0018] Figure 3 is a cross-sectional view of an embodiment of the present invention in a stretched state;

[0019] Figure 4 is a cross-sectional view of a telescopic arm tube assembly in an extended state according to an embodiment of the present invention;

[0020] Figure 5 is a cross-sectional view of a telescopic arm tube assembly in a retracted state according to an embodiment of the present invention;

[0021] Figure 6 is an exploded schematic diagram of a rotation limiting mechanism according to an embodiment of the present invention;

[0022] Figure 7 is a bottom perspective view of a switch cover according to an embodiment of the present invention;

[0023] Figure 8 is a schematic diagram of a lower mounting seat and a metal plate according to an embodiment of the present invention;

[0024] Fig. 9 is a top perspective view of an upper mounting seat according to an embodiment of the present invention;

[0025] Fig.10 is a schematic structural diagram of an inner tube according to an embodiment of the present invention;

[0026] Fig.11Schematic diagram of the structure of the inner rod bushing according to an embodiment of the present invention.

[0027] : The accompanying drawings are marked with: 1 upper mounting seat, 2 lower mounting seat, 3 supporting leg, 4 inclined guide hole, 5 mounting through hole, 6 clearance hole, 7 limiting part, 8 switch rotary cover, 9 center rod, 10 limiting head, 11 special-shaped connecting block, 12 screw lock part, 13 first threaded hole, 14 second threaded hole, 15 special-shaped positioning hole, 16 diameter expansion blocking part, 17 sliding groove, 18 first positioning groove, 19 second positioning groove, 20 sliding block, 21 elastic limiting part, 22 foot pad, 23 protective bottom cover, 24 metal plate, 25 outer tube, 26 inner tube, 27 push rod, 28 inner rod bushing, 29 compression spring, 30 conical part, 301 conical head, 302 center axis, 31 limiting pipe sleeve, 32 annular groove, 33 accommodating hole, 34 rigid sphere, 35 boss, 36 clearance through hole, 37 switch sliding sleeve, 38 sliding rod, 39 sliding hole, 40 mounting hole, 41 switch mark. DETAILED DESCRIPTION

[0028] To further illustrate the various embodiments, the present invention provides drawings. These drawings are part of the disclosure of the present invention, which are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, a person of ordinary skill in the art should be able to understand other possible implementations and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0029] See also Figure 1-11As shown, as an embodiment of the present invention, a telescopic folding chair is provided, including a mounting seat assembly and a seat cushion, the mounting seat assembly includes an upper mounting seat 1 and a lower mounting seat 2 corresponding to each other up and down, four supporting legs 3 are evenly hinged on the outer periphery of the bottom of the upper mounting seat 1, and the rotation adjustment direction of the four supporting legs 3 is to approach or move away from the center of the upper mounting seat 1, and four telescopic arm tube groups are evenly hinged on the outer periphery of the top of the lower mounting seat 2, and the rotation adjustment direction of the four telescopic arm tube groups is to approach or move away from the center of the lower mounting seat 2, and the seat cushion is installed on the four telescopic arm tube groups, and the seat cushion is a mesh cloth, and the telescopic and foldable performance is better, and four inclined guide holes 4 are evenly opened in the circumferential direction of the lower mounting seat 2, and the inclined direction of the inclined guide holes 4 is from top to bottom and gradually inclined away from the center of the lower mounting seat 2, and the inclined guide holes 4 and the telescopic arm tube groups are alternately arranged on the outer periphery of the lower mounting seat 2, and the supporting legs 3 are arranged through the inclined guide holes 4, and a rotation limit is arranged on the upper mounting seat 1 The lower mounting seat 2 is provided with a clearance hole 6, and the bottom of the rotation limit mechanism is a limit head 10. The outer periphery of the lower mounting seat 2 corresponding to the clearance hole 6 is a limit part 7. The rotation limit mechanism rotates to control the limit head 10 to cooperate with the limit part 7 for active limiting. In the extended state, the limit head 10 passes through the clearance hole 6 and is rotated and limited with the limit part 7. The upper mounting seat 1 and the lower mounting seat 2 are abutted and locked up and down. The four supporting legs 3 are tilted and rotated outward under the abutment of the lower mounting seat 2 and the guiding action of the inclined guide hole 4, so as to form a stable support against the ground. The four telescopic arm tube groups are tilted and rotated outward under the abutment of the upper mounting seat 1, thereby driving the seat cushion to be unfolded for the user to sit on; in the retracted state, the limit head 10 and the limit part 7 release the rotation limit and exit the clearance hole 6, and the upper mounting seat 1 and the lower mounting seat 2 are separated from each other, so that the four supporting legs 3 and the four telescopic arm tube groups can be tilted and rotated inward to shrink, completing the folding and storage process. The present invention has a simple structure and can be controlled by one hand, which is more convenient to operate. It can be quickly unfolded and folded, and has high stability, so that users can use it safely and quickly, ensuring the user's usage experience. At the same time, it occupies a small space and is easy to store and carry.

[0030] In this embodiment, the clearance hole 6 is a special-shaped clearance hole, and the limit head 10 is a special-shaped clearance head. The shape and size of the minimum cross-section of the clearance hole 6 are the same as the shape and size of the maximum cross-section of the limit head 10, and the minimum cross-section of the clearance hole 6 is the position of the clearance hole 6 corresponding to the limit part 7, and the maximum cross-section of the limit head 10 is the contact and abutment surface of the limit head 10 corresponding to the limit part 7. The shapes of the cross-sections of the above two can be rectangular or other non-circular special-shaped shapes, so that in the extended state, the limit head 10 passes through the clearance hole 6 and is misaligned with the clearance hole 6 to achieve the rotation limit of the limit head 10 and the limit part 7, and the upper mounting seat 1 and the lower mounting seat 2 are abutted and locked up and down. In the contracted state, the limit head 10 is aligned with the clearance hole 6 and withdraws from the clearance hole 6 to achieve the release of the rotation limit of the limit head 10 and the limit part 7, and the upper mounting seat 1 and the lower mounting seat 2 are separated from each other.

[0031] Of course, the number of the supporting legs 3 and the telescopic arm tube groups is not limited to 4, and other numbers are also possible, such as 3, which is not limited here.

[0032] In this embodiment, the rotation limit mechanism includes a switch cover 8 and a center rod 9, the top end of the center rod 9 is connected to the switch cover 8, the limit head 10 is located at the bottom end of the center rod 9, the switch cover 8 is rotatably arranged on the top of the upper mounting seat 1, the center of the upper mounting seat 1 is provided with a mounting through hole 5, the center rod 9 passes through the mounting through hole 5, specifically, the rotation limit mechanism also includes a special-shaped connecting block 11 and a screw lock 12, the center of the special-shaped connecting block 11 is provided with a first threaded hole 13, the top end of the center rod 9 is provided with a second threaded hole 14, the center of the switch cover 8 is provided with a special-shaped positioning hole 15, the special-shaped connecting block 11 is limitedly installed on the special-shaped positioning hole 15, and the screw lock 12 is sequentially It is threadedly connected to the first threaded hole 13 and the second threaded hole 14, so that the center rod 9 is fixedly connected to the switch cover 8. A diameter expansion blocking portion 16 is formed on the side of the center rod 9 close to the limit head 10. The diameter of the diameter expansion blocking portion 16 is larger than the mounting through hole 5. The top wall of the diameter expansion blocking portion 16 abuts against the bottom wall of the upper mounting seat 1. This arrangement enables the rotation limit mechanism to be quickly and conveniently rotated and installed on the upper mounting seat 1, and ensures that the switch cover 8 will not loosen in the axial direction. The arrangement of the special-shaped connecting block 11 and the special-shaped positioning hole 15 enables the switch cover 8 and the center rod 9 to rotate synchronously, thereby ensuring the control accuracy of the extension and contraction of the telescopic folding chair.

[0033] In this embodiment, the bottom side of the switch cover 8 is provided with a slide groove 17, a first positioning groove 18 and a second positioning groove 19, and the top wall of the upper mounting seat 1 is provided with a slider 20 and an elastic limiter 21. Specifically, the elastic limiter 21 is a spring and a ball connected to each other, the slider 20 and the slide groove 17 are correspondingly slidably matched, and the elastic limiter 21 is respectively elastically limited with the first positioning groove 18 and the second positioning groove 19 to realize the active switching between the extended state and the contracted state. The slider 20 and the slide groove 17 are two corresponding groups, and the elastic limiter 21 and the first positioning groove 18 and the second positioning groove 19 are two corresponding groups, which further improves the rotation limit accuracy of the switch cover 8, thereby improving the telescopic control accuracy of the telescopic folding chair.

[0034] In this embodiment, a foot pad 22 is installed at the bottom end of the support leg 3 to form a reliable and stable support on the ground, and the size of the foot pad 22 is larger than the size of the inclined guide hole 4, ensuring that in the retracted state, the hole wall of the inclined guide hole 4 can block and limit the foot pad 22, thereby preventing the support leg 3 from sliding out of the inclined guide hole 4 as a whole, causing the upper mounting seat 1 to be completely separated from the lower mounting seat 2. A switch mark 41 is provided on the surface of the switch cover 8. When the switch cover 8 is turned counterclockwise, it is in the unlocked and extended state, and when the switch cover 8 is turned clockwise, it is in the locked and retracted state.

[0035] In this embodiment, it also includes a protective bottom cover 23 installed at the bottom of the lower mounting seat 2, which is used to shield and protect the bottom of the lower mounting seat 2 and also improve the aesthetics. A metal plate 24 is installed at the limiting portion 7 to protect the limiting portion 7 and prevent the limiting head 10 from directly contacting the limiting portion 7 for a long time and causing wear, thereby increasing the service life of the present invention.

[0036] In this embodiment, the telescopic arm tube group includes an outer tube 25 and an inner tube 26 that can be slidably and telescopically arranged in the outer tube 25. An elastic cone component and a push rod 27 are arranged in the inner tube 26. The elastic cone component is elastically and telescopically arranged at the bottom of the inner tube 26. A limit sleeve 31 is sleeved on the top of the outer tube 25. An annular groove 32 is formed on the inner wall of the limit sleeve 31. A receiving hole 33 is opened at the bottom of the inner tube 26 corresponding to the position of the elastic cone component. A rigid sphere 34 is arranged in the receiving hole 33. The push rod 27 is used to control the elastic cone. The assembly performs telescopic movement in the inner tube 26, thereby realizing the movable limiting cooperation between the rigid sphere 34 and the annular groove 32, wherein the elastic conical assembly includes an inner rod bushing 28, a compression spring 29 and a conical member 30, the inner rod bushing 28 is sleeved on the bottom periphery of the inner tube 26, the inner rod bushing 28 is provided with a clearance through hole 36, the conical member 30 includes a conical head 301 and a central axis 302, the central axis 302 passes through the clearance through hole 36, the compression spring 29 is sleeved outside the central axis 302, and the compression spring 29 The two ends are respectively in contact with the inner bottom wall of the inner rod bushing 28 and the conical head 301, and the conical head 301 gradually decreases from the central axis 302 toward the push rod 27. In the above technical solution, when it is necessary to slide and retract the inner tube 26 into the inner part of the outer tube 25, the push rod 27 is driven to move downward, thereby pushing the conical member 30 downward, the compression spring 29 is compressed, and the rigid sphere 34 moves inward under the guidance of the conical surface of the conical head 301, thereby releasing the limit fit with the annular groove 32, and then pushing the inner tube 26 downward. 6, the inner tube 26 can be slid and retracted into the inner part of the outer tube 25; when the inner tube 26 needs to be slid and extended out of the outer tube 25, the inner tube 26 is slid and pulled out to the end of the stroke, and then the push rod 27 is pulled upward, and the conical member 30 moves upward and resets under the elastic force of the compression spring 29, so that the rigid sphere 34 moves outward under the guidance of the conical surface of the conical head 301, so that the rigid sphere 34 and the annular groove 32 are limited and matched, and the extension limit fixation between the inner tube 26 and the outer tube 25 can be completed.

[0037] In this embodiment, when the telescopic arm tube group is in the extended use state, the length of the outer tube 25 and the inner tube 26 is greater than twice the length of the support leg 3. In the unfolded state, the angle between the telescopic arm tube group and the central axis of the present invention is set in the range of 10°-50°, and the angle between the support leg and the central axis of the present invention is set in the range of 10°-70° to ensure the supporting effect. In the retracted state, the angle between the telescopic arm tube group, the support leg and the central axis of the present invention is less than 10° to ensure the storage effect.

[0038] In this embodiment, there are two rigid spheres 34 arranged opposite to each other. Of course, the number of the rigid spheres 34 can also be three or one, which can be appropriately adjusted according to the size of the inner tube 26, and is not limited here.

[0039] In this embodiment, the inner rod bushing 28 includes a first inner rod bushing and a second inner rod bushing that are assembled with each other. Bosses 35 are respectively provided on opposite sides of the first inner rod bushing and the second inner rod bushing. Mounting holes 40 are respectively provided on opposite sides of the bottom of the inner tube 26. The bosses 35 correspond to the mounting holes 40. This arrangement ensures that the elastic conical assembly can be conveniently and stably assembled at the bottom of the inner tube 26.

[0040] In this embodiment, it also includes a switch sleeve 37 arranged outside the inner tube 26. Sliding holes 39 are respectively arranged on the opposite sides of the inner tube 26. A sliding rod 38 is arranged on the top of the push rod 27. The sliding rod 38 protrudes out of the sliding hole 39 and is connected to the switch sleeve 37. This arrangement can improve the hand feel and facilitate the user to slide and telescope the telescopic arm tube group.

[0041] Although the present invention has been specifically shown and described in conjunction with the preferred embodiments, it should be understood by those skilled in the art that various changes in form and details made to the present invention without departing from the spirit and scope of the present invention as defined in the appended claims will fall within the scope of protection of the present invention.

Claims

1. A telescopic folding chair, characterized in that: The cam is provided with a plurality of support legs which are hinged on the bottom periphery of the upper mounting seat, and a plurality of telescopic arm tube groups which are hinged on the top periphery of the lower mounting seat. The seat cushion is installed on the plurality of telescopic arm tube groups. A plurality of inclined guide holes are provided in the circumferential direction of the lower mounting seat, and the support legs are penetrated through the inclined guide holes. A rotation limit mechanism is rotatably arranged on the upper mounting seat, and a yield hole is provided on the lower mounting seat. The bottom of the rotation limit mechanism is a limit head, and the periphery of the yield hole corresponding to the lower mounting seat is a limit part. The rotation limit mechanism rotates to control the limit head and the limit part to cooperate with the movable limit. In the extended state, the limit head penetrates through the yield hole and is rotationally limited with the limit part. The upper mounting seat and the lower mounting seat are abutted and locked up and down. In the contracted state, the limit head and the limit part release the rotation limit and exit the yield hole, and the upper mounting seat and the lower mounting seat are separated from each other.

2. The telescopic folding chair according to claim 1, characterized in that: The clearance hole is a special-shaped clearance hole, and the limit head is a special-shaped clearance head. The shape and size of the minimum cross-section of the clearance hole are the same as the shape and size of the maximum cross-section of the limit head. In the extended state, the limit head passes through the clearance hole and is staggered with the clearance hole to achieve rotational limit of the limit head and the limit part, and the upper mounting seat and the lower mounting seat are abutted and locked up and down. In the contracted state, the limit head and the clearance hole are aligned and cooperated and withdraw from the clearance hole to achieve the release of rotation limit of the limit head and the limit part, and the upper mounting seat and the lower mounting seat are separated from each other.

3. The telescopic folding chair according to claim 1, characterized in that: The rotation limit mechanism includes a switch cover and a center rod. The top end of the center rod is connected to the switch cover. The limit head is located at the bottom end of the center rod. The switch cover is rotatably set on the top of the upper mounting seat. A mounting through hole is opened in the center of the upper mounting seat, and the center rod passes through the mounting through hole.

4. The telescopic folding chair according to claim 3 is characterized in that: The rotation limit mechanism also includes a special-shaped connecting block and a screw locking piece. A first threaded hole is provided in the center of the special-shaped connecting block, a second threaded hole is provided at the top end of the center rod, and a special-shaped positioning hole is provided in the center of the switch cover. The special-shaped connecting block is limitedly installed on the special-shaped positioning hole, and the screw locking piece is threadedly connected to the first threaded hole and the second threaded hole in sequence, thereby fixing the center rod to the switch cover. An expansion blocking portion is formed on one side of the center rod close to the limit head, and the diameter of the expansion blocking portion is larger than the mounting through hole. The top wall of the expansion blocking portion abuts against the bottom wall of the upper mounting seat.

5. The telescopic folding chair according to claim 3 is characterized in that: A sliding groove, a first positioning groove and a second positioning groove are arranged on the bottom side of the switch rotary cover, and a sliding block and an elastic limiting member are arranged on the top wall of the upper mounting seat. The sliding block and the sliding groove are correspondingly slidably matched, and the elastic limiting member is elastically limitedly matched with the first positioning groove and the second positioning groove respectively to realize the active switching between the extended state and the contracted state.

6. The telescopic folding chair according to claim 3, characterized in that: A foot pad is installed at the bottom end of the supporting leg, and a switch mark is arranged on the surface of the switch rotary cover.

7. The telescopic folding chair according to claim 1, characterized in that: It also includes a protective bottom cover installed at the bottom of the lower mounting seat, and a metal plate is installed at the limiting part.

8. The telescopic folding chair according to claim 1, characterized in that: The telescopic arm tube group includes an outer tube and an inner tube which is slidably and telescopically arranged in the outer tube. An elastic conical component and a push rod are arranged in the inner tube. The elastic conical component is elastically and telescopically arranged at the bottom of the inner tube. A limiting tube sleeve is provided at the top end of the outer tube. An annular groove is formed on the inner wall of the limiting tube sleeve. An accommodating hole is opened at the bottom of the inner tube corresponding to the position of the elastic conical component. A rigid sphere is arranged in the accommodating hole. The push rod is used to control the elastic conical component to perform telescopic movement in the inner tube, thereby realizing the movable limiting cooperation between the rigid sphere and the annular groove.

9. The telescopic folding chair according to claim 8, characterized in that: The elastic conical component includes an inner rod bushing, a compression spring and a conical part. The inner rod bushing is sleeved on the outer bottom of the inner tube. The inner rod bushing is provided with a clearance hole. The conical part includes a conical head and a center axis. The center axis passes through the clearance hole. The compression spring is sleeved outside the center axis, and the two ends of the compression spring are respectively abutted against the inner bottom wall of the inner rod bushing and the conical head. The conical head gradually decreases from the center axis toward the push rod.

10. The telescopic folding chair according to claim 8, characterized in that: It also includes a switch sliding sleeve arranged outside the inner tube. The inner tube is also provided with a sliding hole. A sliding rod is arranged on the top of the push rod. The sliding rod protrudes out of the sliding hole and is connected with the switch sliding sleeve.

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