Abstract:
Disclosed is a folding stroller, comprising a stroller frame, a front wheel assembly ( 20 ) and a rear wheel assembly ( 30 ), and a locking mechanism provided on the stroller frame and used for locking the stroller frame, and the stroller frame comprises a front support ( 1 ), a rear support ( 2 ) and a seat rod ( 3 ); the front support ( 1 ), the rear support ( 2 ) and the seat rod ( 3 ) are connected with one another to form a triangular three-link mechanism; in the three connection relationships among the three components, two are rotatable connection, and the rest one is relative slidable connection by means of a slider ( 4 ), and the slider ( 4 ) is slidably arranged in the length direction of one of the two connected components and is in rotatable connection with the other component. The stroller can be conveniently folded, has a simple structure, and has good rigidity when unfolded.

Description:
FIELD OF INVENTION 
       [0001]    The present invention relates to a folding stroller. 
       BACKGROUND OF THE INVENTION 
       [0002]    At present, infant/child strollers in the market are mainly two kinds, one is ordinary stroller, and the other is a portable folding stroller. Compared with the ordinary stroller, the folding stroller is convenient, very small when folded, suitable for using when going out, especially when traveling on vehicles such as buses, is very convenient. 
         [0003]    In prior art, the frame of the folding stroller usually comprises a side bracket located on two sides, a bottom support and a rear support provided between the side brackets on the two sides, each side bracket comprising a front bracket, a push rod with the lower part rotatably connected with the upper end part of the front bracket, a rear bracket and a connecting rod, the upper end part of the rear bracket being rotatably connected with the push rod, the connecting rod being provided between the front bracket and the rear bracket, the front end part of the connecting rod being rotatably connected with the front bracket and the rear end part being rotatably connected with the rear bracket, and the connecting rod extending substantially horizontally. It requires multiple steps when folding an existing stroller, and “lift to fold” can not be achieved, and folding operation is not convenient enough, while in the existing strollers, the front bracket and the push rod are often connected by plastic pieces, and with the addition of its own characteristics of the strollers, the frame is prone to collapse inward under the weight-bearing condition, affecting the safety and comfort. In addition, the existing strollers must be provided with connecting rods to strengthen the rigidity of the frame, and have many rod pieces. 
       SUMMARY OF THE INVENTION 
       [0004]    The present invention is intended to provide a folding stroller of simple structure and convenient for fold operation. 
         [0005]    To solve the above problems, the present invention employs the following technical schemes: A folding stroller, comprises a stroller frame with a unfolded state and a folded state, a front wheel assembly and a rear wheel assembly, and a locking mechanism provided on the stroller frame and used for locking the stroller frame, the stroller frame comprising a front support at the bottom of which the front wheel assembly is provided, a rear support at the bottom of which the rear wheel assembly is provided, and a seat rod extending along a front-rear direction; the front support, the rear support and the seat rod are connected with one another to form a triangular three-link mechanism, and in the three connection relationships among the three components, two are rotatable connection, and the rest one is relative slidable connection by means of a slider, the slider being slidably arranged in the length direction of one of the two slidably connected components and being in rotatable connection with the other component of the two slidably connected components. 
         [0006]    In a specific embodiment, the stroller frame comprises side supports on two sides, and the side support on each side respectively comprises the front support, the rear support and the seat rod, and the stroller frame further comprises a support frame connected between the side supports on the two sides and capable of closing up and being folded in a transverse direction. 
         [0007]    Further, the locking mechanism is to lock the slider and the component slidably provided with the slider together, and unlocking elements are respectively provided on the sliders of the side supports on the two sides for unlocking the locking mechanism, two ends of a folding operating element are connected with the unlocking elements on two sides respectively, the locking mechanism is able to be unlocked and the slider is driven to slide by operating the folding operating element such that the front support, the rear support and the seat rod get close and are folded. To achieve a “lift to fold” effect, it just needs to pull the folding operating element to unlock the stroller frame and drive the whole stroller frame to fold. 
         [0008]    According to the present invention, the locking mechanism is not particularly limited. However, the locking mechanism is preferably provided between the slider and the component slidably provided with the slider. 
         [0009]    Further, the locking mechanism comprises a locking element slidably provided on the slider, and a cooperating element provided on the component slidably provided with the slider and cooperating with the locking element to lock, the unlocking element is driven by the folding operating element to drive the locking element to slide and so as to match up with or separate from the cooperating element. 
         [0010]    Further, the cooperating element may be for example a locking hole or a locking slot, etc. 
         [0011]    Further, the unlocking element is rotatably provided on the slider, and the unlocking element and the locking element are rotatably connected. When the unlocking element rotates relative to the slider, the locking element is driven to slide, and so as to match up with or separate from the cooperating element. 
         [0012]    According to a specific aspect, the unlocking element is rotatably connected with the slider by a first pivot, and is rotatably connected with an end of the locking element by a second pivot, the first pivot and the second pivot being parallel, an end of the locking element opposite to said end being locked with the cooperating element. Preferably, the first pivot is more close to the rod piece slidably provided with the slider than the second pivot. 
         [0013]    Further, a reset torsional spring is preferably provided between the slider and the unlocking element, and specifically, two end parts of the reset torsional may be connected to the slider and the unlocking element respectively, or sleeved over a rotating shaft between the slider and the unlocking element. Providing the reset torsional spring may cause the locking mechanism automatically to switch to the locked state from the unlock state, convenient for operation. 
         [0014]    Preferably, the folding operating element is band-shaped. 
         [0015]    Preferably, the slider is a sliding sleeve. 
         [0016]    In a specific embodiment, the support frame comprises a bottom support frame comprising two bottom support rod cross-connected to each other and rotatably connected at the cross point, an end of the bottom support rod is rotatably connected to the front support on one side and the other end of the bottom support rod is rotatably connected to the rear support on the opposite side. 
         [0017]    In a particular embodiment, the support frame comprises a rear support frame capable of closing up and being folded in the transverse direction, and the rear support frame is provided between the rear supports on two sides and comprises: 
         [0018]    a longitudinal connecting rod; 
         [0019]    a first support rod, an end of the first support rod being rotatably connected with an upper end of the longitudinal connecting rod, and the other end of the first support rod being rotatably connected to the rear support on one side; 
         [0020]    a second support rod, an end of the second support rod being rotatably connected with the upper end of the longitudinal connecting rod and the first support rod, and the other end of the second support rod being rotatably connected to the rear support on the other side; 
         [0021]    a third support rod, an end of the third support rod being rotatably connected with a lower end of the longitudinal connecting rod and the second support rod, and the other end of the third support rod being rotatably connected to the rear support on said one side; 
         [0022]    a fourth support rod, an end of the fourth support rod being rotatably connected with the lower end of the longitudinal connecting rod, and the other end of the fourth support rod being rotatably connected to the rear support on the other side; 
         [0023]    a connecting base, slidably provided on the longitudinal connecting rod along the length direction of the longitudinal connecting rod; 
         [0024]    a first slanting rod, an end of the first slanting rod being rotatably connected to the connecting base, and the other end of the first slanting rod being rotatably connected to the third support rod; 
         [0025]    a second slanting rod, an end of the second slanting rod being rotatably connected to the connecting base, and the other end of the second slanting rod being rotatably connected to the fourth support rod; 
         [0026]    when the first support rod and the second support rod are unfolded to extend along the horizontal direction, the connecting base is blocked. Further, a pedal is provided at the connection joint of the longitudinal connecting rod, the third support rod and the fourth support rod. 
         [0027]    Preferably, the stroller frame further comprises a backrest assembly, and the backrest assembly comprises two backrest rods on the two sides, and a connecting rod group provided between the two backrest rods and capable of being folded in the transverse direction, lower ends of the backrest rods being rotatably connected to the seat rod. 
         [0028]    More preferably, the connecting rod group comprises two slanting support rods cross-connected to each other, a lower end of the slanting support rod being rotatably connected to the lower end of the backrest rod on one side, an upper end of the slanting support rods being rotatably connected to an end of a transverse support rod, the other end of the transverse support rod being rotatably connected to an upper end of the backrest rod on the other side. 
         [0029]    In a specific embodiment, an upper part of the front support is fixedly provided with a push handle, and the push handle and the front support form one rod piece. 
         [0030]    In another specific embodiment, the push handle and the front support maybe two rods fixedly connected, the two rods being coaxial and having the same diameter. 
         [0031]    Further, the upper end part of the rear support is connected with the front support, and the front end part and the rear end part of the seat rod are connected with the front support and the rear support respectively, when the stroller frame is in the unfolded state, the connection joint of the front support and the rear support is above the connection joint of the seat pose and the front support as well as the connection joint of the seat pose and the rear support. 
         [0032]    According to a specific and preferable aspect, the rear support and the front support are connected via the slider, and the slider is slidably provided on the front support, and is rotatably connected with the rear support via a pivot. More preferably, when folded, the slider slides upwards along the front support. 
         [0033]    According to another specific aspect, the seat rod and the rear support or the front support are connected via the slider, and the slider is slidably provided on the rear support or the front support, and is rotatably connected with the seat rod via a pivot. 
         [0034]    According to a specific aspect of the present invention, the seat of the stroller is formed by sleeving a cloth cover over the seat rod. The cloth cover has a first part and a second part, the first part being sleeved over the seat rod to form a seat plate, and an upper part of the second part and the front supports at the two sides are connected to form a backrest. 
         [0035]    According to the embodiments of the present invention, each two rotatably connected components are all preferably pivotally connected. 
         [0036]    Due to the use of the above technical schemes, the present invention has the following advantages over the prior art: In the baby stroller of the present invention, the front support, the rear support and the seat rod form a stable triangle structure so as that the stroller frame is in a stable unfolded state; when compared with the conventional stroller structure, this stroller frame has a better rigidity and would not be folded inwardly after carrying a heavy load, and meanwhile, the front supports may play the roles of the front support and the push rod, and stroller has a fewer rod pieces, has a more simple structure, and sharply decreases the production cost than the conventional strollers. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0037]      FIG. 1  is a three-dimensional schematic view of a folding stroller (in the unfolded state) of Embodiment 1; 
           [0038]      FIG. 2  is a schematic side view of  FIG. 1 ; 
           [0039]      FIG. 3  is another three-dimensional schematic view of the stroller (in the unfolded state) of Embodiment 1; 
           [0040]      FIG. 4  is a three-dimensional schematic view of the stroller (during folding) of  FIG. 1 ; 
           [0041]      FIG. 5  is a three-dimensional schematic view of the stroller (in the folded state) of  FIG. 1 ; 
           [0042]      FIG. 6  is a structure schematic view of the Embodiment 1 of  FIG. 1  when the slider is in the locked state; 
           [0043]      FIG. 7  is a structure schematic view of the Embodiment 1 of  FIG. 1  when the slider is in the locked state; 
           [0044]      FIG. 8  is a structure abbreviated diagram of a folding stroller (in the unfolded state) of Embodiment 2; 
           [0045]      FIG. 9  is a structure abbreviated diagram of the folding stroller (during folding) of Embodiment 2; 
           [0046]      FIG. 10  is a structure abbreviated diagram of the folding stroller (in the folded state) of Embodiment 2; 
           [0047]      FIG. 11  is a structure abbreviated diagram of a folding stroller (in the unfolded state) of Embodiment 3; 
           [0048]      FIG. 12  is a structure abbreviated diagram of the folding stroller (during folding) of Embodiment 3; 
           [0049]      FIG. 13  is a structure abbreviated diagram of the folding stroller (in the folded state) of Embodiment 3; 
           [0050]      FIG. 14  is an overall structure schematic view of a baby stroller in unfolded state according to Embodiment 4 of the present invention; 
           [0051]      FIG. 15  is an exploded structure view of the baby stroller according to Embodiment 4; 
           [0052]      FIG. 16  is a overall structure schematic view of the baby stroller in half-folded state as shown in  FIG. 14 ; 
           [0053]      FIG. 17  is a overall structure schematic view of the baby stroller in folded state as shown in  FIG. 14 ; 
       
    
    
       [0054]    Wherein,  20 —front wheel assembly;  30 —rear wheel assembly;  31 —first part;  32 —second part;  10 —side support;  1 —front support;  40   a —lock hole;  2 —rear support;  3 —seat rod;  8 —push rod;  69 —pedal;  4 —slider;  41 —locking element;  42 —unlocking element;  9 —folding operating element;  5 —bottom support frame;  51 —bottom support rod;  6 —rear support frame;  65 —longitudinal connecting rod;  66 —connecting base;  67 —first slanting rod;  68 —second slanting rod;  61 —first support rod;  62 —second support rod;  63 —third support rod;  64 —fourth support rod; a—first pivot; b—second pivot. 
       DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Embodiment 1 
       [0055]    Referring to  FIGS. 1-7 , the present embodiment provides a folding stroller, comprising a stroller frame with a unfolded state and a folded state, a front wheel assembly  20  and a rear wheel assembly  30 . The stroller frame specifically comprises side supports  10  at two sides and symmetric, and a support frame provided between the side supports  10  on the two sides and capable of closing up and being folded in a transverse direction. 
         [0056]    Further, the side support  10  comprises a front support  1  formed by one rod piece and provided with a front wheel assembly  20  at the bottom, a rear support  2  provided with a rear wheel assembly  30 , a seat rod  3  extending along a front-rear direction, and a push handle  8  provided on an upper end part of the front support  1 . The front support  1 , the rear support  2  and the seat rod  3  are connected with one another to form a triangular three-link mechanism. In the shown embodiment, in particular, the front support  1  and the rear support  2  are connected by means of a slider  4 . An upper end part of the rear support  2  and the slider  4  is rotatably connected by means of a pivot. Further, the front end part and the rear end part of the seat rod  3  are respectively rotatably connected with a lower part of the front support  1  and a middle-lower part of the rear support  2  via pivots, and when the stroller frame is in the unfolded state, the connection joint of the front support  1  and the rear support  2  is above the connection joint of the seat pose  3  and the front support  1  as well as the connection joint of the seat pose  3  and the rear support  2 . 
         [0057]    The stroller further comprises a locking mechanism for locking the slider  4  and the front support  1  together, an unlocking element  42  provided on the slider  4  for unlocking the locking mechanism, and a folding operating element  9  connected with the unlocking element  42 . In particular, the folding operating element  9  is band-shaped, and two ends thereof are connected with the unlocking elements  42  on the two sides, respectively. The slider  4  specifically is a sliding sleeve sleeved over the front support  1 . When folding the stroller, pulling the folding operating element  9  upwards may drive the unlocking element  42  to unlock the locking mechanism and drive the slider  4  to slide upwards along the front support  1 , and cause the front support  1 , the rear support  2  and the seat rod  3  to fold and get close. 
         [0058]    Further, the support frame comprises a bottom support frame  5  provided between the front support  1  and the rear support  2  and capable of closing up and being folded in the transverse direction, and a rear support frame  6  provided between two rear supports  2  on the two sides and capable of closing up and being folded in the transverse direction. 
         [0059]    In this embodiment, the bottom support frame  5  comprises a pair of bottom support rods  51  cross-connected to each other and rotatably connected at the cross point, front end parts of the bottom support rods are rotatably connected to the front supports  1  on two sides respectively, and rear end parts are rotatably connected to the rear supports  2  on two side. 
         [0060]    In this embodiment, the rear support frame  6  comprises a longitudinal connecting rod  65 , a connecting base  66  slidably provided on the longitudinal connecting rod  65 , an upper transverse support rod, a lower transverse support rod below the upper transverse support rod, a first slanting rod  67  and a second slanting rod  68 ; the upper transverse support rod comprises a first support rod  61  and a second support rod  62  outer end parts of which are rotatably connected with the rear supports  2  on two sides and inner ends of which are rotatably connected with an upper end part of the longitudinal connecting rod  65 ; the lower transverse support rod comprises a third support rod  63  and a fourth support rod  64  outer end parts of which are rotatably connected with the rear supports  2  on two sides and inner ends of which are rotatably connected with a lower end part of the longitudinal connecting rod  65 ; upper end parts of the first slanting rod  67  and the second slanting rod  68  are rotatably connected to two opposite sides of the connecting base  66  respectively, and lower end parts of the first slanting rod  67  and the second slanting rod  68  are rotatably connected to the outer end parts of the third support rod  63  and the fourth support rod  64  respectively. A pedal  69  is provided at the connection joint of the longitudinal connecting rod  65 , the third support rod  63  and the fourth support rod  64 . 
         [0061]    When the connecting base  66  slides to the upper end of the longitudinal connecting rod  65 , the first support rod  61  and the second support rod  62  are unfolded to extend along the horizontal direction and to block the connecting base  66 , the third support rod  63 , the longitudinal connecting rod  65  and the first slanting rod  67  form a triangle, and the fourth support rod  64 , the longitudinal connecting rod  65  and the second slanting rod  68  form another triangle, the third support rod  63  and the fourth support rod  64  extend in the same line, and the rear support frame  6  is locked to an open state for keeping the distance between the side supports  10  on the left and right sides of the stroller frame fixed; when the third support rod  63  and the fourth support rod  64  rotate relative to each other, the connecting base  66  slides downwardly along the longitudinal connecting rod  65 , the first slanting rod  67  and the second slanting rod  68  rotate correspondingly, and then get close to the third support rod  63 , the fourth support rod  64  and the longitudinal connecting rod  65  gradually, the rear support frame  6  closes up and is folded gradually, and the side supports  10  on two sides close up gradually. The locking mechanism for locking the stroller frame may also lock the rear support frame  6 . 
         [0062]    In this embodiment, the seat of the stroller is formed by sleeving a cloth cover over the seat rod  3 . The cloth cover has a first part  31  and a second part  32 . The first part  31  is sleeved over the seat rod  3  to form a seat plate, and an upper part of the second part  32  and the front supports  1  on the two sides are connected to form a backrest. 
         [0063]    The locking mechanism is not particularly limited, and may employ those common implementations in the art. Specifically in this embodiment, the locking mechanism is preferably provided between the slider  4  and the front support  1 . In particular, see  FIG. 6  and  FIG. 7 , the locking mechanism comprises a locking element  41  slidably provided on the slider  4 , and a locking hole  40   a  or a locking slot or other cooperating element slidably provided on the front support  1  and cooperating with the locking element  41  to lock, when the locking element  41  is inserted into the locking hole  40   a , the locking mechanism is locked, and the slider  4  is locked and cannot slide, and when the locking element  41  separates from the locking hole  40   a , the locking mechanism is unlocked, and the slider  4  can slide. The unlocking element  42  are rotatably connected with the slider  4  and the locking element  41  via a first pivot a and a second pivot b parallel to each other, respectively, wherein the first pivot a is closer to the front support  1  than a second pivot b. When the unlocking element  42  rotates around the first pivot a as axis, and can drive the locking element  41  to slide and match up with or separate from the locking hole  40   a . When rotating along direction F as shown in  FIG. 6 , the locking element  41  is driven by the unlocking element  42  to slide toward a direction facing away from the locking hole  40   a  so as to separate from the locking hole  40   a  and achieve unlocking, conversely, when rotating along a direction opposite to direction F, the locking element  41  is driven by the unlocking element  42  to slide toward a direction close to the locking hole  40   a  so as to insert the locking element  41  into the locking hole  40   a  and achieve locking. In addition, a reset torsional spring is provided between the slider  4  and the unlocking element  42 , and two end portions of the reset torsional are connected with the slider  4  and the unlocking element  42 , respectively. Under the action of the reset torsional spring, the locking mechanism may automatically switch to the locked state from the unlock state. The unlocking elements  42  on two sides are connected via the folding operating element  9 , and by lifting and folding the folding operating element  9 , the unlocking elements  42  rotate around the first pivot a as axis along direction F, and can drive the locking element  41  to slide out from the locking hole  40   a , such that the two sides are unlocked at the same time, and then the slider  4  is driven to slide. The locking mechanism and the unlocking element  42  of this embodiment not only have simple structures, but also are convenient for operating. 
         [0064]    Without specific explanation, the rotatable connections between the above two components are all rotatable connections by means of a pivot. 
         [0065]    The folding process of the baby stroller of this embodiment is as follow: see  FIG. 3 , firstly the rear support frame  6  is unlocked along an upward direction i.e. direction D, then the folding operating element  9  is lifted to move upward to unlock the slider  4 , and then the slider  4  slides along direction A (a direction along the front support  1  and upward) and drives the rear support  2  and the seat rod  3  to rotate relative to the front support  1  and gradually get close to the front support  1 , and the rear support frame  6  closes up along a left-right direction and drives the bottom support frame  5  to close up along the left-right direction, as shown in  FIG. 4 , and finally, the stroller is folded to form a state as shown in  FIG. 5 . 
         [0066]    Above all, the stroller of this embodiment has the following advantages over the existing stroller: very convenient for folding, just lift to fold, more simple structure, more convenient arrangement, well rigidity of the whole stroller, and would not be folded inwardly after carrying a heavy load. 
       Embodiment 2 
       [0067]    The present embodiment provides a folding stroller, see  FIGS. 8-10 , which is basically the same with Embodiment 1 by different in that, the front end part of the seat rod  3  is connected with the lower part of the front support  1 , the seat rod  3  and the rear support  2  as well as the front support  1  and the rear support  2  are rotatably connected via pivots, respectively. The slider  4  can slider along the extending direction of the front support  1 , and is rotatably connected with the seat rod  3  via a pivot. 
         [0068]    When folding the baby stroller of this embodiment, after the rear support frame is unlocking, the folding operating element is lifted to unlock the locking mechanism, and then, the slider  4  is pulled to slide upwardly along the front support  2  and drive the seat rod  3  to rotate relative to the rear support  2  and gradually get close to the rear support  2 , and meanwhile, the rear support  2  is driven to rotate relative to the front support  1  and gradually get close to the front support  1 , the rear support frame closes up along the left-right direction gradually and drives the bottom support frame to close up along the left-right direction, and finally, the stroller is folded to form a state as shown in  FIG. 10 . The stroller of this embodiment also has a “lift to fold” effect. 
       Embodiment 3 
       [0069]    The present embodiment provides a folding stroller, see  FIGS. 11-10 , which is basically the same with Embodiment 1 by differing in that, the rear end part of the seat rod  3  is connected with the rear support  2  via the slider  4 , the seat rod  3  and the rear support  1  as well as the front support  1  and the rear support  2  are rotatably connected via pivots, respectively. The slider  4  can slider along the extending direction of the rear support  2 , and is rotatably connected with the seat rod  3  via a pivot. A locking mechanism is provided between the slider  4  and the rear support  2  to lock them together, and the structure and the principle of this locking mechanism is as the same in Embodiment 1. 
         [0070]    When folding the baby stroller of this embodiment, after the rear support frame is unlocked, the folding operating element is lifted to drive the unlocking element and unlock the locking mechanism, and then, the slider  4  is pulled to slide downwardly along the rear support  2 , and drive the rear support  2  and the seat rod  3  to rotate relative to the front support  1  and gradually get close to the front support  1 , the bottom support frame closes up along the left-right direction gradually, and finally, the stroller is folded to form a state as shown in  FIG. 13 . The stroller of this embodiment also has a “lift to fold” effect. 
       Embodiment 4 
       [0071]    The stroller of the present invention is as shown in  FIGS. 14-17 , the structure thereof is similar to that of the stroller of Embodiment 1 by differing in that, the stroller of the present invention cancels the folding operating element, and a backrest assembly  7  is added to the stroller frame. As shown in  FIG. 15 , the backrest assembly  7  comprises two backrest rods  71  on the two sides, and a connecting rod group provided between the two backrest rods  71  and capable of being folded in the transverse direction, the two backrest rods  71  are parallel to each other, and lower end parts of the backrest rods  71  are rotatably connected to the seat rod  3 . The connecting rod group comprises two slanting support rods  72  cross-connected to each other, a lower end of the slanting support rod  72  is rotatably connected to a lower end of the backrest rod  71  on one side, an upper end of the slanting support rod  72  is rotatably connected to an end of a transverse support rod  73 , and the other end of the transverse support rod  73  is rotatably connected to an upper end of the backrest rod  71  on the other side. When the stroller frame closes up along the left-right direction, the above-mentioned connecting rod group closes up and folds accordingly so as to close up and fold the backrest rod  71  in the transverse direction. 
         [0072]    When the stroller frame in the present invention is unfolded, as shown in  FIG. 14 , the bottom support frame  5  and the rear support frame  6  is unfolded to extend the side supports  10  on two sides, and on the side support  10  of each side, the front support  1 , the rear support  2  and the seat rod  3  form a stable triangle structure, and the side support is in a stable unfolded state. When the stroller frame is required to be folded, firstly the locking mechanism is unlocked, that is, the rear support frame  6  is unlocked, the slider  4  and the front support  1  are unlocked, the slider  4  slides along the front support  1  upward and drives the rear support  2  and the seat rod  3  to rotate relative to the front support  1  and gradually get close to the front support  1 , and the rear support frame  6  closes up along the left-right direction and drives the bottom support frame  5  to close up along the transverse direction, and the backrest assembly  7  also closes up and folds along the transverse direction gradually, as shown in  FIG. 3 , and finally, the stroller is folded to form a state as shown in  FIG. 17 , and the folded structure is compact and occupies less space. When the stroller frame is required to be unfolded, it just needs to push the push handle  8 , kick the rear wheel  30  to rotate the rear support  2  rearward relative to the front support  2 , and drive the slider  4  to slide along the front support  1  downward and drive the seat rod  3  to rotate until the slider  4  is locked to the front support  1 , the front support  1 , the rear support  2  and the seat rod  3  form a triangle structure, and the side support  10  is unfolded, meanwhile, the bottom support frame  5 , the rear support frame  6  and the backrest assembly  7  stretch out along the left-right direction gradually until the rear support frame  6  is in the locking state, the side supports  10  on two sides are fixed relatively, and the stroller frame is in a stable unfolded state. Folding and stretching out the above-mentioned stroller frame is simple and convenient. 
         [0073]    The embodiments described above illustrates the present invention in detail, and is intended to make those skilled in the art being able to understand the present invention and thereby implement it, and should not be concluded to limit the protective scope of this invention. Any equivalent variations or modifications according to the spirit of the present invention should be covered by the protective scope of the present invention.