Patent Publication Number: US-11389000-B2

Title: Reclinable director chair

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The utility model belongs to the technical field of chairs, and particularly relates to a director chair with a reclinable 
     2. Description of Related Art 
     Nowadays, with the vigorous development of social productive forces, people&#39;s material comforts and spiritual pursuits have been greatly improved, more and more large-scale commercial performances, large-scale concerts and evening parties are organized, and some requirements for the comfort and portability of chairs on which users may sit for a long time are put forward. Chairs used on these occasions not only need to be designed to be steady and firm, but also should be attractive, durable and comfortable. Generally, traditional chairs which only allow users to sit thereon are fixed steadily and horizontally, the angle between a horizontal cushion and a vertical backrest perpendicular to the horizontal cushion cannot be adjusted, and once the users feel tired after sitting on the chairs for a long time, the users have to lean their back on the backrest of the chair to relieve fatigue, and in this state, the center of gravity of the users is still focused on the hip and the cushion, so that the feeling of fatigue of the users cannot be effectively eliminated, the users may feel uncomfortable, and the usage requirements of different users cannot be met. 
     In view of this, it is necessary to improve the chairs used on the site of some large-scale commercial performances, competitive concerts, competition area and the like. 
     BRIEF SUMMARY OF THE INVENTION 
     The objective of the utility model is to solve the problem of poor comfort of most existing chairs, used on specific occasions such as large-scale commercial performances, competitive concerts and competition areas, caused by perpendicular arrangement of the backrest and the cushion, and provides a reclinable director chair to improve the long-term sitting comfort of users. 
     To fulfill the above objective, the utility model adopts the following technical solution: 
     A reclinable director chair comprises a chair cloth, a seat frame assembly and a support frame assembly, wherein the seat frame assembly comprises two cross tubes, two square seat frame armrest tubes and two backrest support tubes, the cross tubes are connected and fixed between the two seat frame armrest tubes in a cross manner, one backrest support tube is disposed over the rear end of each seat frame armrest tube, and a cushion and a backrest of the chair cloth are mounted at the upper ends of the cross tubes and on the backrest support tubes respectively; and 
     The support frame assembly comprises two support frame component, each support frame component comprises a bottom support tube and a connector, the rear ends of bottom tubes of the seat frame armrest tubes are bent upwards, bent parts of the bottom tubes are rotatably connected to the bottom support tubes, and the two ends of the connector are rotatably connected to the rear end of one bottom tube and the rear end of one bottom support tube, respectively. 
     Furthermore, each support frame component comprises a foot pad buckle having a lower end fixed to one bottom support tube, and the bent parts of the bottom tubes are rotatably connected to the upper ends of the foot pad buckles. 
     Furthermore, each support frame component further comprises a rocking chair front pad and a rocking chair bottom pad, wherein the rocking chair front pad and the rocking chair bottom pad are fixedly mounted at the front end and the rear end of one bottom support tube respectively, and when the rotating, the bottom tubes of the seat frame armrest tubes abut against upper surfaces of the rocking chair front pads or the rocking chair bottom pads. 
     Furthermore, anti-slip grooves are formed in bottom surfaces of the foot pad buckles, the rocking chair front pads and the rocking chair bottom pads. 
     Furthermore, the connector of the utility model comprises a torsion spring connecting base, a connecting cover, a long hinge pin, a big torsion spring, a middle hinge pin, a small torsion spring and a small hinge pin, wherein a U-shaped support piece is welded to the rear end of each bottom support tube, which is formed with a slot corresponding to the front end of the U-shaped support piece; 
     A notch is formed in the upper end of the torsion spring connecting base, a horizontal opening allowing the connecting cover to retreat in or stretch out is formed in one side of the notch, the small hinge pin penetrates through the connecting cover mounted in the horizontal opening, and the small torsion spring, one end of the small torsion spring is clamped in a clamping groove in the horizontal opening, the other end of the small torsion spring is clamped in a torsion spring groove in the lower surface of the connecting cover, and a clamping protrusion is arranged on the outer edge of the upper surface of the connecting cover; and sliding grooves are formed in two sides of the notch, and the long hinge pin penetrates through the sliding grooves to be rotatably connected to the rear end of the one seat frame armrest tube; 
     The big torsion spring, the lower end of the torsion spring connecting base and the U-shaped support piece are rotatably connected through the middle hinge pin; one end of the big torsion spring is inserted into the slot, and the other end of the big torsion spring is clamped in a clamping groove of a spring clamping plate of the torsion spring connecting base. 
     Furthermore, the connector of the utility model may be of another structure, and particularly, the connector comprises a leaf spring connecting base, a connecting cover, a long hinge pin, a leaf spring, an elastic element mounting shaft, a middle hinge pin, a small torsion spring and a small hinge pin, wherein a U-shaped support piece is welded to the rear end of each bottom support tube, which is formed with a fork hole corresponding to the front end of the U-shaped support piece; 
     A notch is formed in the upper end of the spring connecting base, a horizontal opening allowing the connecting cover to retreat in or stretch out to cover the horizontal opening of the notch is formed in one side of the notch, the small hinge pin penetrates through the connecting cover in the horizontal opening, and the small torsion spring, one end of the small torsion spring is clamped in a clamping groove in the horizontal opening, the other end of the small torsion spring is clamped in a torsion spring groove in the lower surface of the connecting cover, and a clamping protrusion is arranged on the outer edge of the upper surface of the connecting cover; and sliding grooves are formed in two sides of the notch, and the long hinge pin penetrates through the sliding grooves to be rotatably connected to the rear end of one seat frame armrest tube; 
     The leaf spring is of a bent structure and stretches to the lower end of the torsion spring connecting base to be wound on the middle hinge pin, a short edge of the leaf spring is inserted into the fork hole, a long edge of the leaf spring is clamped in a concave groove below the leaf spring connecting base, and the lower end of the leaf spring connecting base and the U-shaped support piece are rotatably connected through the middle hinge pin. 
     Furthermore, each cross tube is of an n-shaped structure formed by a horizontal rod and two symmetrical vertical rods, the vertical rods of the two cross tubes are riveted, and the two ends of each cross rod are riveted to the two vertical tubes of one seat frame armrest tube respectively; and the chair cloth is in an L shape, two vertical sleeve tubes are arranged on the back of the backrest of the chair cloth and are disposed around backrest support tubes, and horizontal sleeve tubes are arranged on two sides of the cushion of the chair cloth and are disposed around the horizontal rods. 
     Furthermore, the seat frame assembly further comprises four protective sleeves, two connecting iron sheets and two bent iron sheets, wherein the protective sleeves are riveted to the vertical tubes of the seat frame armrest tubes, the two protective sleeves on one seat frame armrest tube are connected to the two bent iron sheets, the two protective sleeves on the other seat frame armrest tube are connected to the two connecting iron sheets, the other ends of the two connecting iron sheets are riveted to the two vertical rods of one cross tube, and the two bent iron sheets are riveted to the two vertical rods of the other cross tube. 
     Furthermore, the seat frame assembly further comprises four plastic buckles, one plastic buckle is arranged on the upper side of each connecting iron sheet, one plastic buckle is arranged on the upper side of each bent iron sheet, and when the two cross tubes are in an unfolded state, the horizontal rods of the two cross tubes press against the plastic buckles. 
     Furthermore, the seat frame assembly further comprises U-shaped leaf springs, wherein a protrusion is arranged on a U-shaped face of one side of each U-shaped leaf spring, throats are formed at the lower ends of the backrest support tubes, a through hole is formed in the periphery of each throat, the U-shaped springs are arranged in inner cavities of the throats in a sleeved manner, and the protrusions stretch out of the through holes; 
     Vertical openings are formed in upper portions of the rear ends of the seat frame armrest tubes, small holes are formed in the side walls of the vertical openings, the throats at the lower ends of the backrest support tubes having the U-shaped leaf springs mounted thereon are inserted into the vertical openings, and the protrusions stretch out of the small holes. 
     Compared with the prior art, the utility model has the following beneficial effects: the cushion and backrest of the director chair can be reclined to relieve or eliminate the fatigue caused by long-time sitting, and the usage requirement of users for comfort is effectively met; and the reclinable director chair has the advantages of being simple in structure, portable, attractive, elegant, firm, durable, and high in practicability. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIG. 1 a    is a front perspective view of a reclinable director chair in a flat state; 
         FIG. 1 b    is a back perspective view of the reclinable director chair in the flat state; 
         FIG. 2 a    is a front perspective view of the reclinable director chair in a reclining state; 
         FIG. 2 b    is a back perspective view of the reclinable director chair in the reclining state; 
         FIG. 3  is an exploded view of a seat frame assembly of the reclinable director chair; 
         FIG. 4 a    is a disassembled explosive view of a cross tube and a U-shaped leaf spring; 
         FIG. 4 b    is an assembled view of the cross tube and the U-shaped leaf spring; 
         FIG. 5  is an explosive view of a support frame and a seat frame assembly of the reclinable director chair; 
         FIG. 6  is an exploded view of a support frame component in  FIG. 5 ; 
         FIG. 7 a    is a connection diagram of a big torsion spring in  FIG. 5 ; 
         FIG. 7 b    is a schematic diagram of the big torsion spring with the bottom turned in  FIG. 5 ; 
         FIG. 8 a    is an assembled diagram of another support frame component of the reclinable director chair; 
         FIG. 8 b    is a disassembled view of another support frame component of the reclinable director chair; 
         FIG. 9  is a connection diagram of a leaf spring in  FIG. 8 . 
     
    
    
     In the figures:  1 , chair cloth;  2 , seat frame assembly;  3 , cross tube;  4 , support frame assembly;  5 , connector;  6 , connecting cover;  7 , vertical sleeve tube;  8 , horizontal sleeve tube;  9 , seat frame armrest tube;  10 , protective sleeve;  11 , plastic buckle;  12 , connecting iron sheet;  13 , small step shaft;  14 , small hollow shaft;  15 , long groove;  16 , bent iron sheet;  17 , small hole;  18 , protrusion;  19 , backrest support rod;  20 , U-shaped leaf spring;  21 , rocking chair front pad;  22 , anti-slip groove;  23 , bottom support tube;  24 , foot pad buckle;  25 , side cover;  26 , rocking chair bottom pad;  27 , torsion spring connecting base;  28 , bearing;  29 , semicircular buckle structure;  30 , slot;  31 , U-shaped support piece;  32 , small hinge pin;  33 , clamping protrusion;  34 , small torsion spring;  35 , big torsion spring;  36 , middle hinge pin;  37 , long hinge pin;  38 , spring clamping plate;  39 , torsion spring groove;  40 , sliding groove for bearing rolling;  41 , leaf spring;  42 , bottom support tube II;  43 , elastic element mounting shaft;  44 , fork leg;  45 , leaf spring connecting base;  46 , fork hole. 
     DETAILED DESCRIPTION OF THE INVENTION 
     To gain a clearer and better understanding of the technical solution of the invention, the technical solution is further expounded below with reference to specific embodiments. Those skilled in the art can easily appreciate other advantages and effects of the invention according to the contents disclosed in this specification. The utility model can also be implemented or applied by means of other different specific embodiments. All details in this specification can be modified or changed without deviating from the spirit of the utility model, based on different viewpoints and applications. 
     Embodiment 1 
     This embodiment discloses a reclinable director chair which is mainly characterized in that a cushion and a backrest can be adjusted to a reclining state from a flat state. The reclinable director chair is typically composed of a chair cloth  1 , a seat frame assembly  2  and a support frame assembly  4 . Assembled parts and assembled structures of the director chair are shown in structural views in the flat state ( FIG. 1 ) and axonometric drawings in the reclining state ( FIG. 2 ), wherein the chair cloth  1  is disposed around the seat frame assembly  2  in an L shape, cross tubes  3  are connected and fixed to the middle of the seat frame assembly  2  in a cross manner, and the support frame assembly  4  is connected to the bottom of the seat frame assembly  2  and is supported on the ground. 
     As shown in  FIG. 3 , the chair cloth  1  is in an L shape, two vertical sleeve tubes  7  are designed behind a backrest side of the chair cloth  1  and allow two backrest support rods  19  disposed around the seat frame assembly  2  to be mounted therein, and horizontal sleeve tubes  8  are designed on two sides of a cushion side of the chair cloth  1  and are disposed around two horizontal rods of the two cross tubes  3 . 
     Specifically, the reclinable director chair comprises the chair cloth  1 , the seat frame assembly  2  and the support frame assembly  4 , wherein the seat frame assembly  2  comprises the two cross tubes  3 , two square seat frame armrest tubes  9  and two backrest support tubes  19 , wherein the cross tubes  3  are connected and fixed between the two seat frame armrest tubes  9  in a cross manner, one backrest support tube  19  is arranged over the rear end of each seat frame armrest tube  9 , and a cushion and a backrest of the chair cloth  1  are mounted at the upper ends of the cross tubes  3  and on the backrest support tubes  19 , respectively; the support frame assembly  4  comprises two support frame components, each support frame component comprises a bottom support tube  23  and a connector  5 , the rear ends of bottom tubes of the seat frame armrest tubes  9  are bent upwards, bent parts of the bottom tubes are rotatably connected to the bottom support tubes  23 , and the two ends of each connector  5  are rotatably connected to the rear end of one bottom tube and the rear end of one bottom support tube  23 , respectively. 
     On the basis of the bottom support tube  23  and the connector  5 , each support frame component of the support frame assembly  4  of the reclinable director chair, as shown in  FIG. 5  and  FIG. 6 , further comprises a foot pad buckle  24 , a rocking chair front pad  21  and a rocking chair bottom pad  26 , wherein the lower end of the food pad buckle  24  is fixed to the bottom support tube  23 , and the rocking chair front pad  21  and the rocking chair bottom pad  26  are disposed around the front end and the rear end of the bottom support tube  23  respectively. Wherein, the bent parts of the bottom tubes are rotatably connected to the upper ends of the foot pad buckles  24 , the rocking chair front pads  21  and the rocking chair bottom pads  26  are fixedly mounted at the front ends and the rear ends of the bottom support tubes  23  respectively, and when rotating, the bottom tubes of the seat frame armrest tubes  9  abut against the upper surfaces of the rocking chair front pads  21  or the rocking chair bottom pads  26 . 
     The rocking chair bottom pad  26  is mounted at the other end of the bottom support tube  23  with a rivet (or screw), and an anti-slip groove  22  is designed in the bottom surface of the rocking chair bottom pad  26 . The rocking chair front pad  21  is similar to human&#39;s forefeet in shape, an anti-slip groove  22  is designed in a side, in contact with the ground, of the rocking chair front pad  21 , an oblate hole matched with the bottom support tube  23  is formed in a flat end of the rocking chair front pad  21 , and the rocking chair front pad  21  is disposed around one end of the bottom support tube  23  and penetrates through the oblate hole to be fixed to the bottom support tube  23  with a rivet (or screw). Through the design of the anti-slip groove  22 , the anti-slip performance of the rocking chair bottom pad is improved, and the director chair can be placed more steadily. The rocking chair front pad  21  is preferably made of rubber. 
     As a specific structure of the foot pad buckle, the foot pad buckle  24  in this embodiment, as shown in  FIG. 5  and  FIG. 6 , is formed by two symmetrical parts and two bearings  28  which are assembled together, and is arranged close to the middle of the bottom support tube  23 , wherein the two symmetrical parts of the foot pad buckle  24  are fixedly mounted with rivets (or screws), the lower end of one symmetrical part is buckled on an oblate shell of the bottom support tube  23  in a half-closed manner through a semicircular buckle structure  29  and realizes a closed state together with the other symmetrical part, semicircular notches are formed in the sides, towards one seat frame armrest tube  9 , of the symmetrical parts, one seat frame armrest tube  9  is mounted in bearing seat mounting holes in two sides of the semicircular notches of the foot pad buckle  24  through a small step shaft  13  and the bearings  28 . An anti-slip groove  22  is also designed in the side, towards the ground, of the rocking chair bottom pad  26 . 
     In one specific implementation, the connector  5  comprises a torsion spring connecting base  27 , a connecting cover  6 , a long hinge pin  37 , a big torsion spring  35 , a middle hinge pin  36 , a small torsion spring  34  and a small hinge pin  32 , wherein a U-shaped support piece  31  is welded to the upper surface of the rear end of each bottom support tube  23 , which is formed with a slot  30  corresponding to the front end of the U-shaped support piece  31 ; a notch is formed in the upper end of the torsion spring connecting base  27  and is of a Y-shaped structure, a horizontal opening allowing the connecting cover  6  to retreat in or stretch out (or to slide) is formed in one side of the notch, the small hinge pin  32  penetrates through the connecting cover  6  mounted in the horizontal opening, and the small torsion spring  34 , one end of the small torsion spring  34  is clamped in a clamping groove in the horizontal opening, the other end of the small torsion spring  34  is clamped in a torsion spring groove  39  in the lower surface of the connecting cover  6 , and a clamping protrusion  33  is arranged on the outer edge of the upper surface of the connecting cover  6 ; sliding grooves  40  are formed in two sides of the notch, and the long hinge pin  37  penetrates through the sliding grooves  40  to be rotatably connected to the rear end of one seat frame armrest tube  9 ; the big torsion spring  35 , the lower end of the torsion spring connecting base  27  and the U-shaped support piece  31  are rotatably connected through the middle hinge pin  36 ; one end of the big torsion spring  35  is inserted into the slot  30 , and the other end of the big torsion spring  35  is clamped in a clamping groove of a spring clamping plate  38  of the torsion spring connecting base  27  (as shown in  FIG. 7 ). The connecting cover  6  is mainly used to cover the notch; in the case where the connecting cover  6  is not pushed with an external force, the connecting cover  6  covers the Y-shaped notch of the torsion spring connecting base  27  under the effect of the small torsion spring  34 , and the clamping protrusion  33  is exactly clamped outside the side edge of the Y-shaped notch of the torsion spring connecting base  27 . Preferably, the side edge, towards the corresponding seat frame armrest tube  9 , of the connecting cover  6  is designed as an oblique edge. 
     In addition, the connector  5  further comprises two side covers  25 , two bearings  28  and an elastic element mounting shaft  43 , wherein a rotating part of the big torsion spring  35  is mounted on the elastic element mounting shaft  43 , the middle hinge pin  36  penetrates through the elastic element mounting shaft  43 , and the entire torsion spring connecting base  27  is mounted on and rotatably connected to the U-shaped support piece  31  of the bottom support tube  23  through the middle hinge pin  36 . The long hinge pin  37  penetrates through the corresponding seat frame armrest tube  9  through a small hollow shaft  14 , the bearings  28  are mounted at the two ends of the long hinge pin  37  and are arranged in the sliding grooves  40  of the torsion spring connecting base  27  in a rolling and sliding manner, and horizontal openings of the sliding grooves  40  in two sides of the Y-shaped open end of the torsion spring connecting base  27  are covered with the two side covers  25 . 
     In a preferred implementation, each cross tube  3 , as shown in  FIG. 1 a   - FIG. 3 , is of an n-shaped structure formed by a horizontal rod and two symmetrical vertical rods, the vertical rods of the two cross tubes  3  are riveted (with rivets or screws), and the two symmetrical ends of each horizontal rod are riveted to the two vertical tubes of one seat frame armrest tube  9 , respectively; the chair cloth  1  is in an L shape, two vertical sleeve tubes  7  are arranged on the back side of the backrest of the chair cloth  1  and are disposed around backrest support tubes  19 , and horizontal sleeve tubes  8  are arranged on two sides of the cushion of the chair cloth  1  and are disposed around the horizontal rods. 
     Preferably, the seat frame assembly further comprises four protective sleeves  10 , two connecting iron sheets  12  and two bent iron sheets  16 , wherein the protective sleeves  10  are riveted to the vertical tubes of the seat frame armrest tubes  9 , the two protective sleeves  10  on one seat frame armrest tube  9  are connected to the two bent iron sheets  16 , the two protective sleeves  10  on the other seat frame armrest tube  9  are connected to the two connecting iron sheets  12 , the other ends of the two connecting iron sheets  12  are riveted to the two vertical rods of one cross tube  3 , and the two bent iron sheets  16  are riveted to the two vertical rods of the other cross tube  3 . The two cross tubes  3  are mounted between the two seat frame armrest tubes  9  in a cross manner, the upper ends, namely the horizontal rods, are connected to the two bent iron sheets and the two connecting iron sheets  12  through rivets (or screws), and the lower ends (open ends) are connected to the two seat frame armrest tubes  9  through rivets (or screws). A long groove  15  is formed in one of the two bent iron sheets  16  to be used for assembly and adjustment. 
     Preferably, the seat frame assembly in this embodiment further comprises four plastic buckles  11 , one plastic buckle  11  is bucked on the upper side of each connecting iron sheet  12 , one plastic buckle  11  is buckled on the upper side of each bent iron sheet  16 , and the four plastic buckles  11  are fixedly connected through rivets (or screws). When the two cross tubes are in an unfolded state, the horizontal rods of the two cross tubes  3  press against the plastic buckles  11 . 
     Preferably, the seat frame assembly in this embodiment further comprises U-shaped leaf springs  20 , a protrusion  18  is arranged on the U-shaped face of one side of each U-shaped leaf spring  20 , throats are arranged at the lower ends of the backrest support tubes  19 , a through hole is formed in the periphery of each throat, the U-shaped leaf springs  20  are arranged in inner cavities of the throats in a sleeved manner, and the protrusions  18  stretch out of the through holes; and vertical openings are formed in upper portions of the rear ends of the seat frame armrest tubes  9 , small holes  17  are formed in the side walls of the vertical openings, the throats at the lower ends of the backrest support tubes  19  having the U-shaped leaf spring  20  mounted thereon are inserted into the vertical openings, and the protrusions  18  stretch out of the small holes  17 . 
     As shown in  FIG. 1 , in the case where a user horizontally sits on the director chair, the working condition of the director chair adopting the cross tubes and the torsion springs is as follows: 
     When the user sits on the reclinable director chair which is flatly placed on the ground, the whole director chair is pressed to rotate forward around a fulcrum formed by the small step shafts  13  and the foot pad buckles  24  on the seat frame armrest tubes  9  and the bearings  28 , under the effect of the center gravity of the user, so that the front ends of the lower oblate tubes of the seat frame armrest tubes  9  are pressed against the shells of the rocking chair front pads  21 . At this moment, the big torsion springs  35  are assembled and pre-tightened between the torsion spring connecting bases  27  and the bottom support tubes  23 , the connecting covers  6  block the Y-shaped notches of the torsion spring connecting bases  27  under the assembling and pre-tightening effect of the small torsion springs  34 , so that the Y-shaped notches are sealed and covered (foreign matter or fingers are prevented from being stretched into the Y-shaped notches by mistake, otherwise, the fingers may be pinched when the seat frame armrest tubes  9  are reclined). 
     As shown in  FIG. 2 , the operating principle of the director chair adopting the cross tubes and the torsion springs and allowing the user to recline thereon is as follows: 
     When the user sits on the director chair adopting the cross tubes and the torsion springs and reclines by a certain angle, the whole director chair is pressed to rotate backwards around fulcrum formed by the small step shafts  13  and the foot pad buckles  24  on the seat frame armrest tubes  9  and the bearings  28 , with the backward movement of the center gravity of the user, so that the front ends of the lower oblate tubes of the seat frame armrest tubes  9  are separated from the shells of the rocking chair front pads  21 . At this moment, the big torsion springs  35  are stressed and pressed between the torsion spring connecting bases  27  and the bottom support tubes  23 , the seat frame armrest tubes  9  roll and slide in the sliding grooves  40  for bearings rolling of the torsion spring connecting bases  27  through the small hollow shafts  14 , the long hinge pins  37  and the bearings  28 , so that the whole torsion spring connecting bases  27  can rotate towards the bottom support tubes  23  around the fulcrum formed by the U-shaped support pieces  31  and the middle hinge pins  36  on the bottom support tubes  23 . At this moment, the oblique edges of the connecting covers  6  are squeezed by the inclining seat frame armrest tubes  9  to rotate towards the outside of the Y-shaped notches of the torsion spring connecting bases  27  around the fulcrum formed by the small torsion springs  34  and the small hinge pins  32 . When the oblate tubes on the small hollow shafts  14  of the seat frame armrest tubes  9  are completely clamped in the most concave portions of the Y-shaped notches of the torsion spring connecting bases  27 , and at this moment, the director chair with the cross tubes and the torsion springs are reclined by the maximum angle (an angle range allowing the user to comfortably, stably and safely recline on the chair). 
     Embodiment 2 
     Different from Embodiment 1, this embodiment provides a support frame assembly  4  of another structure, which is different from support frame assembly in the above embodiment mainly in the connector  5  and adopts leaf spring components, as shown in  FIG. 8 a   ,  FIG. 8 b    and  FIG. 9 . The overall assembled diagram of the support frame assembly  4  adopting the leaf spring structure is shown in  FIG. 8 a   , and the exploded view of the parts of the support frame assembly  4  adopting the leaf spring structure is shown in  FIG. 8 b   . Specifically, each support frame component of the support frame assembly  4  in this embodiment is mainly composed of a rocking chair front pad  21 , a bottom support tube II  42 , two foot pad buckles  24 , a rocking chair bottom pad  26 , two bearings  28  and two connectors  5 , wherein the rocking chair front pad  21 , the bottom support tube II  42 , the two foot pad buckles  24  and the rocking chair bottom pad  26  are connected in the same manner as Embodiment 1. The connector  5  comprises a leaf spring connecting base  45 , a connecting cover  6 , two side covers  25 , two bearings  28 , a long hinge pin  37 , a leaf spring  41 , an elastic element mounting shaft  43 , a middle hinge pin  36 , a small torsion spring  34  and a small hinge pin  32 , wherein a U-shaped support piece  31  is welded to the rear end of each bottom support tube  23 , which is formed with a fork hole  46  corresponding to the front end of the U-shaped support piece  31 ; 
     A notch is formed in the upper end of the leaf spring connecting base  45 , a horizontal opening allowing the connecting cover  6  to retreat in or stretch out to cover the notch is formed in one side of the notch, the small hinge pin  32  penetrates through the connecting cover  6  mounted in the horizontal opening, and the small torsion spring  34 , one end of the small torsion spring  34  is clamped in a clamping groove in the horizontal opening, the other end of the small torsion spring  34  is clamped in a torsion spring groove  39  in the lower end face of the connecting cover  6 , and a clamping protrusion  33  is arranged on the outer edge of the upper surface of the connecting cover  6 ; sliding grooves  40  are formed in two sides of the notch, and the long hinge pin  37  penetrates through the sliding grooves  40  to be rotatably connected to the rear end of one seat frame armrest tube  9 ; the leaf spring  41  is of a bent structure and stretches to the lower end of one torsion spring connecting base  27  to be wound on the middle hinge pin  36 ; a short edge of the leaf spring  41  is inserted into the fork hole  46 , a long edge of the leaf spring  41  is clamped in a concave groove below the leaf spring connecting base  45 , and the lower end of the leaf spring  45  and the U-shaped support piece  31  are rotatably connected through the middle hinge pin  36 . 
     Preferably, the connector  5  in this embodiment further comprises two side covers  25 , two bearings  28  and an elastic element mounting shaft  43 , wherein a bent part (an arc wrap angle formed by the long edge and the short edge) of the leaf spring  41  is wound on the elastic element mounting shaft  43 , the middle hinge pin  36  penetrates through the elastic element mounting shaft  43 , and the whole torsion spring connecting base  27  is mounted on and rotatably connected to the U-shaped support piece  31  of one bottom support tube  23  through the middle hinge pin  36 . The long hinge pin  37  penetrates through the seat frame armrest tube  9  through a small hollow shaft  14 , the bearings  28  are mounted at the two ends of the long hinge pin  37  and are arranged in the sliding grooves  40  of the torsion spring connecting base  27  in a rolling and sliding manner, and horizontal openings of the sliding grooves  40  in the two sides of the Y-shaped open end of the torsion spring connecting base  27  are covered with the two side covers  25 . 
     In one implementation, the leaf spring  41  is in the shape of an open fork, wherein two fork legs  44  are arranged on a short edge of the leaf spring and are inserted into the two fork holes  46  which are correspondingly designed in the bottom support tube II  42 . 
     The above embodiments are merely preferred ones of the utility model, and are not intended to limit the protection scope of the utility model. All transformations and improvements made by those skilled in the art according to the design concept of the utility model should also fall within the protection scope of the utility model. More specifically, various transformations and improvements can be made to the components and/or layout of the subject matter of the utility model within the scope defined by the disclosure, drawings and claims of this application. In addition to the transformations and improvements made to the components and/or layout of the subject matter, other applications of the utility model will also be obvious to those skilled in the art.