CN220308732U - Folding chair - Google Patents

Abstract

The utility model discloses a folding chair which comprises a pair of backrest pipes, a pair of seat pipes, a pair of armrests, a pair of vertical telescopic supporting legs, a left foot pipe assembly, a right foot pipe assembly, a back cross pipe assembly and a front cross pipe assembly, wherein the front cross pipe assembly is linked with the two seat pipes, the back cross pipe assembly is linked with the two seat pipes and the two backrest pipes, the two seat pipes are controlled and tensioned by the pair of vertical telescopic supporting legs, and a telescopic locking assembly capable of locking and unlocking telescopic actions of the vertical telescopic supporting legs is arranged at the tops of the two vertical telescopic supporting legs. According to the folding chair, the width of the chair is locked through the pair of vertical telescopic supporting legs and the two telescopic locking assemblies, so that the purpose of locking the width of the back of the chair is achieved, the cloth of the chair surface is tightened, the chair surface is smoother, and the sitting feeling is better. The folding and unfolding operations are more convenient, the height after folding is smaller, and the packaging volume is small, so that the storage and the transportation are convenient.

Description

Folding chair

Technical Field

The utility model relates to the field of folding chairs, in particular to a folding chair.

Background

The folding chair is often used in various training institutions, schools at all levels, hospitals, companies, families and other places, and is a necessary tool for outdoor activities such as camping. The existing folding chairs are inconvenient to fold, a plurality of locking devices are required to be unfolded, the folding volume is large, the folded height is too high, the folding chairs are inconvenient to store and transport, the chair cloth cannot be stretched, sitting feel is uncomfortable, and the folding chairs are easy to scatter (poor in stability) when being folded and folded.

Disclosure of Invention

Aiming at the defects of the prior art, the utility model provides a folding chair, which solves the problems of uneven cloth on the chair surface, uncomfortable sitting feeling, easy dispersion (poor stability) during folding and folding placement and the like in the prior art.

In order to achieve the above purpose, the utility model is realized by the following technical scheme:

the utility model provides a folding chair, includes a pair of back pipe, a pair of seat pipe, a pair of handrail, a pair of vertical flexible landing leg, left foot pipe subassembly, right foot pipe subassembly, back cross pipe subassembly, preceding cross pipe subassembly and two seat pipe linkage, back cross pipe subassembly and two seat pipe and two back pipe linkage, two seat pipes are controlled the tensioning by a pair of vertical flexible landing leg, and two vertical flexible landing leg tops are equipped with the flexible locking component that can lock and unblock the flexible action of vertical flexible landing leg.

Further, the upper end of the back cross tube assembly is hinged with the two backrest tubes, the lower end of the back cross tube assembly is hinged with the rear ends of the two seat tubes, the lower ends of the two backrest tubes are respectively hinged with the rear positions of the middle parts of the two seat tubes, and the upper end of the back cross tube assembly is inclined forwards in the unfolding state of the folding chair, and the two seat tubes, the two backrest tubes and the back cross tube assembly form a triangular supporting structure.

Further, the left foot tube assembly and the right foot tube assembly comprise a rear foot tube and a front foot tube, a sliding connecting seat is sleeved on the rear foot tube, the sliding connecting seat is provided with a sliding hole for the rear foot tube to be inserted into, a first hinge groove and a second hinge groove which are positioned at two ends of the sliding Kong Tongyi side, the first hinge groove and the second hinge groove are respectively provided with two opposite groove walls, the lower end of the backrest tube is positioned between the two groove walls of the first hinge groove and hinged with the two groove walls of the first hinge groove, the seat tube is positioned between the two groove walls of the second hinge groove and hinged with the two groove walls of the second hinge groove, a groove communicated with the second hinge groove is formed in the middle of the bottom surface of the sliding connecting seat, and the top surface of the groove is used as a limiting surface for being contacted with the seat tube in the unfolded state of the folding chair to limit the maximum sliding position of the sliding connecting seat on the rear foot tube.

Further, the upper end of the front foot tube is hinged with the rear foot tube, the front foot tube is connected with the rear foot tube in a herringbone manner, two opposite hinged plates extend out of the bottom of the handrail, the upper end of the rear foot tube is positioned between the two hinged plates and is riveted with the two hinged plates, the rear end of the handrail is hinged with the backrest tube on the same side, and the backrest tube, the handrail tube and the rear leg tube on the same side form a triangular structure.

Further, the lower ends of the two outer supporting legs are fixedly provided with foot pads, the lower ends of the front cross tube assemblies are hinged with the two foot pads, and the lower ends of the front foot tubes are hinged with the foot pads on the same side.

Further, the front foot pipe is hinged with the seat pipe at the same side, one side or two sides of the folding chair are provided with cup holder assemblies, each cup holder assembly comprises a cup holder body, a cup holder connecting piece and a cup holder fixing piece, the cup holder bodies and the cup holder connecting pieces are riveted and fixed, the cup holder fixing pieces are sleeved on the front foot pipe and are provided with slots, the cup holder connecting pieces are detachably inserted into the slots of the cup holder fixing pieces from top to bottom, and the cup holder fixing pieces, the front foot pipe and the seat pipe at the same side are riveted through the same rivet.

Further, flexible locking component includes lock seat, button, spring, tenon, and the button is articulated with the lock seat, and the spring is located between button and the lock seat, vertical flexible landing leg includes interior landing leg, outer landing leg and spacer, and spacer embedding outer landing leg top is in order to separate interior landing leg and outer landing leg, is equipped with the mortise on the outer landing leg, and the spring provides the pretension that makes the tenon insert the interior landing leg of butt in the mortise of outer landing leg, enables the tenon break away from outer landing leg in order to realize the unblock through the pressing part of pressing the button.

Further, the lock seat bottom is equipped with the blind hole that the opening is down, forms a boss in front of the lock seat, is equipped with on the boss and runs through the hinge hole of lock seat front and back two sides with the blind hole intercommunication, and in the interior landing leg top was inserted this blind hole, preceding cross pipe subassembly upper end and boss contact, preceding cross pipe subassembly and interior landing leg realized through same root rivet with the riveting of lock seat.

Further, a key installation groove is formed in one side of the lock seat, the middle of the key is riveted with two groove walls of the key installation groove, a pressing part is formed at one end of the key, a convex column is formed at one side of the pressing part, which faces the groove bottom of the key installation groove, a convex column is formed at the groove bottom of the key installation groove, the two convex columns are inserted into two ends of the spring to position the spring, the tenon is connected to one side, which faces the key installation groove, of the other end, which is far away from the pressing part, of the key installation groove, and a perforation which is opposite to the mortise on the outer supporting leg and is used for the tenon to pass through is formed at the groove bottom of the key installation groove; the lock seat top is equipped with the U type groove that is used for supporting seat pipe, and the U type groove extends along fore-and-aft direction, and two lateral walls in U type groove extend backward and form two relative arm clamps, and seat pipe hinge connection is between two arm clamps.

Further, the front cross tube assembly and the rear cross tube assembly comprise a long cross tube, two short cross tubes and two connecting sheets, one ends of the two short cross tubes are fixed between the two connecting sheets, the middle part of the long cross tube is inserted between the two connecting sheets and hinged with the middle parts of the two connecting sheets, the front cross tube assembly and the rear cross tube assembly are of X-shaped cross structures, and the rear cross tube assembly is connected with the two seat tubes and the two backrest tubes through U-shaped connecting pieces.

The folding chair has the following beneficial effects:

when the folding chair is unfolded, the vertical telescopic support legs are automatically locked, and the front cross tube is locked by the vertical telescopic support legs, so that the unfolding width of the two seat tubes is fixed, the unfolding width of the rear cross tube assembly is fixed while the two seat tubes are fixed, so that the unfolding width of the two backrest tubes is fixed, the backrest tubes are hinged to the seat tubes through sliding connection seats, when the sliding connection seats slide to the limiting surfaces along the rear leg tubes to abut against the seat tubes, the triangular structures formed by the backrest tubes, the armrest tubes and the rear leg tubes are fixed, namely the inclined angles of the backrest tubes are limited when the sliding pieces are not sliding downwards when the sliding pieces abut against the seat tubes, in addition, the rear cross tube assembly, the two backrest tubes and the two seat tubes are in triangular support structures, the whole structure of the chair frame is fixed, the front cross tube assembly and the rear cross tube assembly are not required to be provided with locking devices, and the folding chair is well fixed in an unfolding state while the vertical telescopic support legs are automatically locked, and the structure is stable.

The seat width is locked through the pair of vertical telescopic supporting legs and the two telescopic locking assemblies, so that the purpose of locking the seat back width is achieved, the seat cloth is tight, the seat is smoother, and the sitting feeling is better. The folding and unfolding operations are more convenient, the height after folding is smaller, and the packaging volume is small, so that the storage and the transportation are convenient. In the unfolded state, the two seat pipes, the two backrest pipes and the back cross pipe form a triangular supporting structure, and the structure is stable.

Drawings

FIG. 1 is a schematic view of an embodiment of the present utility model in an unfolded state of a folding chair;

FIG. 2 is a schematic view of the folding chair of FIG. 1 in a semi-folded state;

FIG. 3 is a schematic view of the folding chair of FIG. 1 in a folded state;

FIG. 4 is an assembled view of the vertical telescoping leg, telescoping locking assembly and footpad;

FIG. 5 is a schematic view of a lock base;

FIG. 6 is a schematic view of the assembly direction of the lock base and the key;

FIG. 7 is an assembled cross-sectional view of the telescoping lock assembly and vertical telescoping leg;

FIG. 8 is a broken schematic view of a vertical telescoping leg;

FIG. 9 is a schematic view of the spacer and outer leg separated;

FIG. 10 is a schematic view of a slide connection seat;

FIG. 11 is another angular view of the slide connection seat;

FIG. 12 is an assembled directional schematic view of the cup holder assembly;

fig. 13 is a side view showing an unfolded state of the folding chair according to the embodiment of the present utility model.

Description of the reference numerals: 1. a backrest tube; 2. a seat tube; 3. an armrest; 4. a vertical telescopic support leg; 5. a back cross tube assembly; 6. a telescoping locking assembly; 7. a front cross tube assembly; 8. a rear foot tube; 9. a front foot tube; 10. a cup holder assembly; 11. foot pads; 12. a sliding connecting seat; 13. a U-shaped connecting piece; 41. an inner leg; 42. an outer leg; 43. a spacer bush; 44. a limiting hole; 45. a limit protrusion; 46. mortises; 61. a lock base; 62. a key; 63. a spring; 64. a tenon; 65. a U-shaped groove; 66. a clamp arm; 67. a blind hole; 68. a key installation groove; 69. a pressing part; 610. a convex column; 611. perforating; 612. a boss; 101. a cup holder body; 102. a cup holder connector; 103. a cup holder fixing member; 31. a hinged plate; 121. a sliding hole; 122. a first hinge groove; 123. a second hinge groove; 124. a limiting surface; 51. a long cross tube; 52. short cross pipes; 53. and a connecting sheet.

Detailed Description

The utility model is further described below with reference to the drawings and examples.

In the description of the present utility model, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate description of the present utility model and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

As shown in fig. 1 to 13, the present embodiment discloses a folding chair, which comprises a pair of backrest pipes 1, a pair of seat pipes 2, a pair of armrests 3, a pair of vertical telescopic legs 4, a left foot pipe assembly, a right foot pipe assembly, a back cross pipe assembly 5, a front cross pipe assembly 7, wherein the front cross pipe assembly 7 is linked with two seat pipes 2, the back cross pipe assembly 5 is linked with two seat pipes 2 and two backrest pipes 1, the two seat pipes 2 are tensioned under the control of the pair of vertical telescopic legs 4, and a telescopic locking assembly 6 capable of locking and unlocking the telescopic actions of the vertical telescopic legs 4 is arranged at the top of the two vertical telescopic legs 4. When the folding chair is unfolded, the vertical telescopic support legs are automatically locked, and the front cross pipe is locked by the vertical telescopic support legs, so that the unfolding width of the two pipes is fixed.

The upper end of the back cross tube assembly 5 is hinged with the two backrest tubes 1, the lower end of the back cross tube assembly 5 is hinged with the rear ends of the two seat tubes 2, the lower ends of the two backrest tubes 1 are respectively hinged with the rear positions of the middle parts of the two seat tubes 2, the upper end of the back cross tube assembly 5 is inclined forwards in the unfolding state, and the two seat tubes 2, the two backrest tubes 1 and the back cross tube assembly 5 form a triangular supporting structure, as shown in figure 13. The triangular support structure forms stable support for the back of the human body and ensures that the whole chair frame structure is stable.

In the embodiment, the rear section of the seat tube is bent and tilted upwards, so that the folding chair is attractive in appearance, the length of the rear cross tube assembly is reduced, and the total length of the folding chair in the front-rear direction is controlled, so that the cost is saved.

The vertical telescopic support leg 4 comprises an inner support leg 41, an outer support leg 42 and a spacer 43, wherein the spacer 43 is embedded into the top of the outer support leg 42 to separate the inner support leg 41 from the outer support leg 42, so that the inner support leg 41 and the outer support leg 42 are prevented from being worn in direct contact. In this embodiment, a pair of limiting protrusions 45 are formed at two ends of the spacer 43, and a pair of limiting holes 44 are formed on the outer leg 42, and the two limiting protrusions 45 slide into the two limiting holes 44, so that the spacer 43 and the outer leg 42 are fixed. In other embodiments, the number of the limit protrusions 45 is not limited to two, but may be one or more. The spacing protrusion 45 is preferably in a shape gradually expanding from bottom to top, and the spacing protrusion 45 in the shape is easy to be clamped into the spacing hole 44 from top to bottom, but is not easy to be pulled out from bottom to top, so that the spacer 43 is not easy to be pulled out from the outer supporting leg 42, and the connection is firm.

The two telescopic locking assemblies 6 are respectively hinged with the two seat pipes 2 and are respectively hinged with the upper ends of the front cross pipe assemblies 7. The telescopic locking assembly 6 comprises a lock seat 61, a key 62, a spring 63 and a tenon 64. The top of the lock seat 61 is provided with a U-shaped groove 65 for supporting the seat tube 2, the U-shaped groove 65 extends along the front-back direction, two side walls of the U-shaped groove 65 extend backwards to form two opposite clamping arms 66, and the seat tube 2 is hinged between the two clamping arms 66. Specifically, the two clamp arms 66 and the seat tube 2 are provided with opposite hinge holes, and the seat tube 2 is riveted with the two clamp arms 66.

The bottom of the lock seat 61 is provided with a blind hole 67 with a downward opening, a boss 612 is formed in front of the lock seat 61, the boss 612 is provided with a hinge hole which is communicated with the blind hole 67 and penetrates through the front surface and the rear surface of the lock seat 61, the top of the inner supporting leg 41 is inserted into the blind hole 67, the upper end of the front cross tube assembly 7 is contacted with the boss 612, and the front cross tube assembly 7 and the inner supporting leg 41 are riveted with the lock seat 61 through the same rivet, so that the assembly steps are reduced, and the assembly procedure is simplified. Boss 612 reduces the contact area of the front cross tube assembly 7 with the lock base 61, reducing surface wear of the front cross tube assembly 7.

As shown in fig. 5 to 7, a key mounting groove 68 is formed on one side of the lock seat 61, the middle of the key 62 is riveted with two groove walls of the key mounting groove 68, a pressing portion 69 is formed at one end of the key 62, a boss 610 is formed on one side of the pressing portion 69 facing the groove bottom of the key mounting groove 68, a boss 610 is formed at the groove bottom of the corresponding key mounting groove 68, two bosses 610 are inserted into two ends of the spring 63 to position the spring 63, a tenon 64 (the tenon 64 is connected with the key 62 through a pin or a rivet) is connected to the other end of the key 62 facing the key mounting groove 68, a through hole 611 for the tenon 64 to pass through is formed at the groove bottom of the key mounting groove 68, a mortise 46 opposite to the through hole 611 is formed on the outer leg 42, the spring 63 provides a pretightening force for enabling the tenon 64 to protrude out of the through hole 611 and be inserted into the mortise 46 of the outer leg 42 to abut against the inner leg 41, and at this time the tenon 64 locks the telescopic action of the vertical telescopic leg 4, and the tenon 64 can be disengaged from the outer leg 42 by pressing the pressing portion 69 of the key 62. When the telescopic locking assembly 6 is locked, the height and the width of the seat are locked, and the purpose of locking the back width of the seat is achieved by locking the width of the seat.

The left foot tube assembly and the right foot tube assembly comprise a rear foot tube 8 and a front foot tube 9, the upper end of the front foot tube 9 is hinged with the rear foot tube 8, the front foot tube 9 is connected with the rear foot tube 8 in a herringbone manner, and a backrest tube, a handrail tube and a rear leg tube on the same side form a triangle structure.

The front foot pipe 9 is hinged with the seat pipe 2 at the same side near the upper end part, and is provided with a cup holder assembly 10 at the hinged position, as shown in fig. 12, the cup holder assembly 10 comprises a cup holder body 101, a cup holder connecting piece 102 and a cup holder fixing piece 103, the cup holder body 101 is provided with a cavity for accommodating articles such as a cup, the cup holder body 101 and the cup holder connecting piece 102 are riveted and fixed, the cup holder fixing piece is sleeved on the front foot pipe and is provided with a slot, the cup holder connecting piece 102 is detachably connected with the slot of the cup holder fixing piece 103 from top to bottom, and the cup holder fixing piece 103, the front foot pipe 9 and the seat pipe 2 are riveted through the same rivet. The two sides of the folding chair of the embodiment are provided with cup holder assemblies, and in other embodiments, the cup holder assembly 10 can be arranged on one side of the chair frame.

The rear ends of the two armrests 3 are respectively hinged with the backrest tubes 1 on the same side, and the two armrests 3 are respectively hinged at the top of the left foot tube assembly and the top of the right foot tube assembly. Specifically, the bottom of the armrest 3 extends out of two opposite hinge plates 31, and the upper end of the caster 8 is located between the two hinge plates 31 and rivets the two hinge plates 31. The two hinge plates 31 in this embodiment are integrally formed with the armrest 3, thereby reducing fittings and assembly processes. The connection between the armrest 3 and the rear leg pipe 8 is not limited to the one described in the present embodiment, but in other embodiments, for example, the armrest 3 and the rear leg pipe 8 may be connected by a common U-shaped connector 13.

The lower ends of the two outer supporting legs 42 are fixedly provided with foot pads 11, the lower ends of the front cross tube assemblies 7 are hinged with the two foot pads 11, the lower ends of the front foot tubes 9 are hinged with the foot pads 11 on the same side, and the lower ends of the rear foot tubes 8 are provided with foot sleeves.

Each of the rear leg pipes 8 is sleeved with a sliding connection seat 12, as shown in fig. 10 and 11, the sliding connection seat 12 is provided with a vertical sliding hole 121 for inserting the rear leg pipe 8 therein, a first hinge groove 122 and a second hinge groove 123 positioned at two ends of the same side of the sliding hole 121, the first hinge groove 122 and the second hinge groove 123 are respectively provided with two opposite groove walls, opposite hinge holes are arranged on the two opposite groove walls, the lower end of the backrest pipe 1 is positioned between the two groove walls of the first hinge groove 122 and hinged with the two groove walls of the first hinge groove 122, the seat pipe 2 is positioned between the two groove walls of the second hinge groove 123, and the middle rear position of the seat pipe 2 is hinged with the two groove walls of the second hinge groove 123. The sliding connection seat 12 limits the seat tube 2 when the seat tube 2 rotates, and plays a role in fixing.

The lower end of the backrest pipe 1 is hinged between the two groove walls of the first hinge groove 122, the middle part of the seat pipe 2 is hinged between the two groove walls of the second hinge groove 123 at the back position, the connection stability is enhanced, the abrasion of the hinge shaft or the hinge hole after multiple folding and unfolding is avoided, the connection precision is reduced, the backrest pipe 1 and the seat pipe 2 on the same side are ensured to be hinged on the same plane, and compared with the scheme of the backrest pipe 1 on one side of the seat pipe 2, the width of the folding chair is reduced.

The middle part of the bottom surface of the sliding connection seat 12 is concaved inwards to form a groove communicated with the second hinge groove 123, and the top surface of the groove is used as a limiting surface 124 which is contacted with the seat tube 2 in the unfolded state of the folding chair to limit the rotation angle of the seat tube 2. The sliding connecting seat 12 is sleeved on the rear foot pipe 8 and can slide on the rear foot pipe. The back tube, the seat tube 2 and the two ends of the sliding connecting seat 12 are riveted, can be rotated and folded, and the sliding connecting seat 12 has a limit design (limit surface) and is naturally fixed when reaching a limit position.

The front cross tube assembly 7 and the rear cross tube assembly 5 comprise a long cross tube 51, two short cross tubes 52 and two connecting sheets 53, one ends of the two short cross tubes 52 are fixed between the two connecting sheets 53, the middle part of the long cross tube 51 is inserted between the two connecting sheets 53 and hinged with the middle parts of the two connecting sheets 53, and the front cross tube assembly 7 and the rear cross tube are of an X-shaped cross structure. The back cross tube assembly 5 connects the two seat tubes 2 and the two back tubes 1 by means of a U-shaped connector 13.

The telescopic locking assembly 6 is installed, when the key 62 is pressed, the tenon 64 is pulled out to unlock, and the chair can be telescopic and folded; the spring 63 presses and locks the tenon 64 when the key 62 is released, the height and the width of the seat are locked when the seat is unfolded, the width of the seat is locked, the width of the seat back is locked, the seat surface is smoother, the sitting feeling is better, and the seat is locked to prevent loosening when the seat is folded. The chair frame has the advantages that the adopted pipe fitting is short, the height after folding is low, and the packaging volume is small, so that the storage and the transportation are convenient.

The embodiments are merely illustrative of the technical solution of the present utility model, and not limiting thereof; although the utility model has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some of the technical features thereof can be replaced with equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present utility model, and therefore all other embodiments obtained by those skilled in the art without making creative efforts are intended to fall within the protection scope of the present utility model.

Claims (10)

1. A folding chair, characterized in that: including a pair of back pipe, a pair of seat pipe, a pair of handrail, a pair of vertical flexible landing leg, left foot pipe subassembly, right foot pipe subassembly, back cross pipe subassembly, preceding cross pipe subassembly and two seat pipe linkage, back cross pipe subassembly and two seat pipe and two back pipe linkage, two seat pipes are controlled tensioning by a pair of vertical flexible landing leg, and two vertical flexible landing leg tops are equipped with the flexible locking component that can lock and unblock the flexible action of vertical flexible landing leg.

2. The folding chair as in claim 1, wherein: the upper end of the back cross tube assembly is hinged with the two backrest tubes, the lower end of the back cross tube assembly is hinged with the rear ends of the two seat tubes, the lower ends of the two backrest tubes are respectively hinged with the rear positions of the middle parts of the two seat tubes, the upper end of the back cross tube assembly is tilted forwards in the unfolded state of the folding chair, and the two seat tubes, the two backrest tubes and the back cross tube assembly form a triangular supporting structure.

3. The folding chair as in claim 1, wherein: the left foot tube assembly and the right foot tube assembly comprise a rear foot tube and a front foot tube, a sliding connecting seat is sleeved on the rear foot tube, the sliding connecting seat is provided with a sliding hole for the rear foot tube to be inserted into, a first hinge groove and a second hinge groove which are positioned at two ends of the side of the sliding Kong Tongyi, the first hinge groove and the second hinge groove are respectively provided with two opposite groove walls, the lower end of the backrest tube is positioned between the two groove walls of the first hinge groove and hinged with the two groove walls of the first hinge groove, the seat tube is positioned between the two groove walls of the second hinge groove and hinged with the two groove walls of the second hinge groove, a groove communicated with the second hinge groove is formed in the middle of the bottom surface of the sliding connecting seat in an inward concave mode, and the top surface of the groove is used as a limiting surface which is in contact with the seat tube under the unfolding state of the folding chair to limit the maximum sliding position of the sliding connecting seat on the rear foot tube.

4. A folding chair as claimed in claim 3, wherein: the upper end of the front foot pipe is hinged with the rear foot pipe, the front foot pipe is connected with the rear foot pipe in a herringbone manner, two opposite hinged plates extend out of the bottom of the handrail, the upper end of the rear foot pipe is positioned between the two hinged plates and is riveted with the two hinged plates, the rear end of the handrail is hinged with the backrest pipe on the same side, and the backrest pipe, the handrail pipe and the rear leg pipe on the same side form a triangular structure.

5. The folding chair as in claim 4, wherein: the lower ends of the two outer supporting legs are fixed with foot pads, the lower ends of the front cross tube assemblies are hinged with the two foot pads, and the lower ends of the front foot tubes are hinged with the foot pads on the same side.

6. A folding chair as claimed in claim 3, wherein: the front foot pipe is hinged with the seat pipe on the same side, one side or two sides of the folding chair are provided with cup holder assemblies, each cup holder assembly comprises a cup holder body, a cup holder connecting piece and a cup holder fixing piece, the cup holder bodies and the cup holder connecting pieces are riveted and fixed, the cup holder fixing pieces are sleeved on the front foot pipe and are provided with slots, the cup holder connecting pieces are detachably inserted into the slots of the cup holder fixing pieces from top to bottom, and the cup holder fixing pieces, the front foot pipe and the seat pipe on the same side are riveted through the same rivet.

7. The folding chair as in claim 1, wherein: the telescopic locking assembly comprises a lock seat, a key, a spring and a tenon, wherein the key is hinged with the lock seat, the spring is positioned between the key and the lock seat, the vertical telescopic supporting leg comprises an inner supporting leg, an outer supporting leg and a spacer, the spacer is embedded into the top of the outer supporting leg to separate the inner supporting leg from the outer supporting leg, the outer supporting leg is provided with a mortise, the spring provides a pretightening force for enabling the tenon to be inserted into the mortise of the outer supporting leg to abut against the inner supporting leg, and the tenon can be separated from the outer supporting leg by pressing a pressing part of the key so as to realize unlocking.

8. The folding chair as in claim 7, wherein: the lock seat bottom is equipped with the blind hole that the opening was down, forms a boss in front of the lock seat, is equipped with on the boss and runs through the hinge hole of lock seat front and back two sides with the blind hole intercommunication, and in the inner leg top was inserted this blind hole, preceding cross pipe subassembly upper end and boss contact, preceding cross pipe subassembly and inner leg realized with the riveting of lock seat through same root rivet.

9. The folding chair as in claim 7, wherein: the lock seat is characterized in that a key installation groove is formed in one side of the lock seat, the middle of the key is riveted with two groove walls of the key installation groove, a pressing part is formed at one end of the key, a convex column is formed at one side of the pressing part, which faces the groove bottom of the key installation groove, a convex column is formed at the groove bottom of the key installation groove, the two convex columns are inserted into two ends of the spring to position the spring, the tenon is connected to one side, which faces the key installation groove, of the other end, which is far away from the pressing part, of the key installation groove, and a perforation which is opposite to the mortise on the outer supporting leg and is used for the tenon to pass through is formed at the groove bottom of the key installation groove; the lock seat top is equipped with the U type groove that is used for supporting seat pipe, and the U type groove extends along fore-and-aft direction, and two lateral walls in U type groove extend backward and form two relative arm clamps, and seat pipe hinge connection is between two arm clamps.

10. The folding chair as in claim 1, wherein: the front cross tube assembly and the rear cross tube assembly are of X-shaped cross structures, and the rear cross tube assembly is connected with the two tubes and the two backrest tubes through U-shaped connecting pieces.