Abstract:
A collapsible stroller whose collapsing operation in both width direction and front/rear direction can be performed simultaneously with just one hand of the user is provided. The collapsible stroller of the present invention comprises a frame including a pair of front leg tubes and a pair of rear leg tubes pivotally collapsibly coupled to the front legs; a seat unit including a pair of seat side-tubes and a pair of backrest tubes; a first collapsing auxiliary assembly horizontally collapsibly disposed between lateral sides of the frame and operably coupled to the side-tubes of the site unit and the rear leg tubes; a second collapsing auxiliary assembly disposed between the rear leg tubes; and an operation unit operably coupled to the side-tubes of the seat unit and releasibly coupled to the rear leg tubes of the frame, thereby the two dimensional collapsing operation of the stroller can be performed by one hand of the user and the volume of the collapsed strolled is minimized.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates generally to a collapsible stroller, and more specifically to a collapsible stroller whose collapsing operation in both width direction and front/rear direction can be performed simultaneously with just one hand. 
       BACKGROUND OF THE INVENTION 
       [0002]    A stroller becomes necessary equipment for a family that has a baby when the parents need to take the baby to the outdoors, and it is usually designed in a collapsible form to facilitate handling/storing. For instance, U.S. patent publication No. 2003/0201626 A1 has disclosed a collapsible stroller. However, although this type of collapsible strollers are able to collapse in height direction and front/rear direction (depth direction), the size in the width direction of the stroller is not reduced, that is, the width of the stroller remains unchanged after the stroller being collapsed. Therefore, reducing the volume of a collapsed stroller to a maximum degree is not fully achieved. 
         [0003]    U.S. Pat. No. 7,178,822 disclosed a stroller frame structure allowing the stroller being collapsed in two different directions. Specifically, this collapsible stroller frame structure can be collapsed in both the front/rear direction (depth direction) and width direction so as to reduce the volume of the collapsed stroller. Although this type of collapsible stroller design allows the width of the stroller to be reduced after being collapsed, it requires two steps and/or two hands of the user to perform the collapsing operation. Therefore, from simplifying the collapsing operation point of view, this type of stroller obviously does not meet the easy-to-use requirement. 
         [0004]    Therefore, there exists a need for a collapsible stroller that the collapsing operation can be operated with one hand of a user and the volume of the collapsed stroller can be minimized. 
       SUMMARY OF THE INVENTION 
       [0005]    Accordingly, one object of the present invention is to provide a collapsible stroller whose collapsing operation in both width direction and front/rear direction can be performed simultaneously with just one hand of a user. 
         [0006]    Another object of the present invention is to provide a collapsible stroller that allows the size in the width dimension (lateral dimension), height dimension and front/rear dimension (longitudinal dimension) to be reduced while collapsing the stroller such that the volume of the collapsed stroller can be minimized. 
         [0007]    To achieve these and other objects, a collapsible stroller is provided, the collapsible stroller comprising:
       a frame, including:
           two front leg tubes, each of the front leg tubes having a first end and a second end on which a wheel is rotatably attached; and   two rear leg tubes, each of the rear leg tubes having a first end pivotally coupled to a corresponding front leg tube at a vicinity of the first end thereof to form a lateral side of the frame respectively and a second end on which a wheel is rotatably attached;   
           a seat unit including two seat side-tubes, each of the side-tubes having a first end pivotally coupled to a corresponding front leg tube and a second end;   a collapsing operation unit operably coupled to the seconds of the seat side-tubes,   the collapsible stroller being characterized in that:   when the second ends of the seat side-tubes respectively coupled to a corresponding rear leg tube on the same side of the frame, the collapsing operation unit operably locks the seat side-tubes to the rear leg tubes, and when the collapsing operation unit unlocks and disengages the seat side-tubes from the rear leg tubes, the second ends of the seat side-tubes separate with the rear leg tubes and pivot relative to the front leg tubes.       
 
         [0015]    In this embodiment, the first end of each of the front leg tubes has a substantially L-shaped handle tube telescopely coupled to the front leg tube through a handle tube adjustment means. The stroller further includes a second collapsing auxiliary assembly lateral collapsibly disposed between the rear leg tubes. The second collapsing auxiliary assembly includes an upper connecting block, a guiding tube extending downwardly from a lower end of the upper connecting block, two upper horizontal members each pivotally coupled between a lateral side of an upper end of the upper connecting block and a corresponding rear leg tube, a lower connecting block mounted to a lower end of the guiding tube, two lower horizontal members each pivotally coupled between a lateral side of the lower connecting block and a lower end portion of a corresponding rear leg tube, and two connecting members each having one end pivotally coupled to a lower end of a lateral side of the upper connecting block and another end pivotally coupled, together with a corresponding lower horizontal member, to the lower end portion of a corresponding rear leg tube. 
         [0016]    The collapsing operation unit includes a actuating member and two locking members each pivotally coupled to one end of the actuating member for operably connected to a corresponding seat side-tube, wherein the actuating member includes an intermediate portion and two connecting portions, one end of each of the connecting portions being pivotally coupled to one end of the intermediate portion and the other end being pivotally coupled to a corresponding locking member. 
         [0017]    The locking member includes a locking hook portion formed at the end to be locking to the seat later tube, and a bias means disposed between the locking member and the seat side-tube for biasing the locking member toward the seat side-tube to thereby allow the locking hook portion being operably locked to/unlocked and disengaged from the corresponding rear leg tube. 
         [0018]    According to another embodiment of the present invention, the actuating member of the collapsing operation unit is an one-piece member that is made of a elastically deformable plastic material. The seat unit further includes two crossing members and two backrest tubes, each of the backrest tube being pivotally coupled to a corresponding seat side-tube and the crossing members being foldably disposed between the backrest tubes to thereby provide the backrest of the seat unit additional mechanical strength and facilitate the folding/expanding operation of the bake-rest tubes. 
         [0019]    The collapsible stroller further includes a first collapsing auxiliary assembly lateral collapsibly disposed between lateral sides of the frame. The first collapsing auxiliary assembly includes two crossing tubes and two first linking-up members, wherein a first end of each of the crossing tubes is pivotally coupled to a corresponding front leg tube and a second end thereof is pivotally coupled to the second end of the seat side-tube at the lateral side of the frame opposite to the corresponding front leg tube to which the second end is coupled, and one end of each of the first linking-up members is pivotally coupled a seat side-tube and the other end is pivotally coupled to a corresponding rear leg tube to thereby allow the first collapsing auxiliary assembly to facilitate the collapsing operation of the stroller in both the lateral direction (width direction) and the front/rear direction. 
         [0020]    Features and objects of the present invention other than the above will become clear by reading the description of the present specification with reference to the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]    For a more complete understanding of the present invention and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings in which illustrative and non-imitative embodiments are shown, wherein: 
           [0022]      FIG. 1  is a schematic perspective view illustrating a collapsible stroller according to a first embodiment of the present invention; 
           [0023]      FIG. 2  is an enlarged perspective view showing the, collapsing operation unit of the collapsible stroller according to the first embodiment of the present invention; 
           [0024]      FIG. 3  is an exploded perspective of the collapsing operation unit illustrated in  FIG. 2 ; 
           [0025]      FIGS. 4   a - 4   d  are drawings illustrating the structure of the handle tube adjusting means, wherein  FIG. 4   a  is an exploded perspective of the handle tube adjusting means, 
           [0026]      FIG. 4   b  is an assembled perspective view,  FIGS. 4   c  and  4   d  are cross-sectional views showing the locked state and unlocked state of the handle tube adjusting means respectively; 
           [0027]      FIGS. 5   a - 5   c  are drawings illustrating the operation states of collapsible stroller according to the first embodiment of the present invention; 
           [0028]      FIG. 6  is a schematic perspective view illustrating a collapsible stroller according to a second embodiment of the present invention; 
           [0029]      FIG. 7  is an enlarged perspective view showing the collapsing operation unit of the collapsible stroller according to the second embodiment of the present invention; and 
           [0030]      FIGS. 8   a - 8   b  are drawings illustrating the operation states of collapsible stroller according to the second embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0031]    Referring now to the drawings in which preferred embodiments of the present invention are illustrated to describe the present invention. 
         [0032]      FIG. 1  is a schematic perspective view illustrating a collapsible stroller according to a first embodiment of the present invention. As shown in  FIG. 1 , the collapsible stroller mainly comprises a frame  1 , a seat unit  4 , a first collapsing auxiliary assembly  3 , a collapsing operation unit  5  and a second collapsing auxiliary assembly  20 . The frame  1  mainly includes two front leg tubes  12  and two rear leg tubes  13 , wherein each of the front leg tubes  12  has a front leg tube lower end portion and a front leg tube upper end portion, and each of the rear leg tubes  13  has a rear leg tube lower end portion and a rear leg tube upper end portion. The upper end portion of each of the rear leg tubes  13  is pivotally coupled to the upper end portion of a corresponding front leg tube  12  to form a lateral side of the frame  1  (i.e., the left/right side of the frame  1 ). Additionally, a front wheel  14  is rotatably attached to the lower end of each of the front leg tubes  12  and a rear wheel  15  is rotatably attached to the lower end of each of the rear leg tubes  13 . As seen in  FIG. 1 , a substantially L-shaped handle tube  16  is telescopely and adjustably received in the upper end portion of each of the front leg tubes  12  through a handle tube adjusting means  17  to adjust a length of the handle tube  16  relative to the front leg tube  12  by sliding the handle tube  16  relative to the front leg tube  12 . In addition, a flexible guard member  18  (e.g., a guard member made of a soft plastic material) is provided between the upper end portions of the two rear leg tubes  13 . 
         [0033]    The seat unit  4  mainly comprises two seat side-tubes  42  disposed opposite to each other, a front end of each of the seat side-tubes  42  being coupled to a corresponding front leg tube  12  and a rear end thereof being detachably coupled to a corresponding rear leg tube  13  through a seat tube supporting member  41  mounted on the rear leg tube  13 . As shown in  FIGS. 2 and 3 , the seat tube supporting member  41  has a groove  411  for detachably supporting the rear end of the seat side-tube  42 . The seat unit  4  further comprises two backrest tubes  44  each having an end pivotally coupled to a corresponding seat side-tube  42 . 
         [0034]    The first collapsing auxiliary assembly  3  includes two crossing tubes  33  each having a first end pivotally coupled to a front leg tube  12  through a reversed L-shaped connecting member  36  and a second end pivotally coupled to a rear end of a seat side-tube  42  through another connecting member  36  at a lateral side of the frame  1  opposite to the front leg tube  12  to which the first end is coupled, thereby the two crossing tubes  330  intersecting at a substantially center of the frame  1  to allow the lateral sides of the frame  1  to be collapsed toward each other or expanded away from each other by a scissor-like movement of the crossing tubes  33 . 
         [0035]    The first collapsing auxiliary assembly  3  includes two first linking-up members  34  each being disposed at an outer side of a corresponding seat side-tube  42  with a front end thereof pivotally being coupled to a substantially middle portion of the seat side-tube  42  and a rear end thereof being pivotally coupled to a corresponding seat tube supporting member  41  so as to allow the rear leg tubes  13  to be moved toward the front leg tubes  12  by the first linking-up members  34  driven by a collapsing movement of the two seat tubes  42  during a collapsing operation of the stroller. 
         [0036]    Additionally, the first collapsing auxiliary assembly  3  includes two second linking-up members  37  each having a first end pivotally to the rear end of a corresponding first linking-up members  34  and a second end pivotally coupled a corresponding upper horizontal member  24  of the second collapsing auxiliary assembly  20  at a vicinity of the coupling location of the upper horizontal member  24  and the rear leg tube  13 . 
         [0037]    As shown in  FIG. 1 , the second collapsing auxiliary assembly  20  is disposed between the two rear leg tubes  13  closer to the lower ends to which the rear wheels  15  are attached. The second collapsing auxiliary assembly  20  includes an upper connecting block  21 , a guiding tube  22  extending downwardly from a lower end of the upper, connecting block  21 , two upper horizontal members  24  each pivotally coupled between a lateral side of an upper end of the upper connecting block  21  and a corresponding rear leg tube  13 , a lower connecting block  23  mounted to a lower end of the guiding tube  22 , two lower horizontal members  26  each pivotally coupled between a lateral side of the lower connecting block  23  and a lower end portion of a corresponding rear leg tube  13 , and two connecting members  25  each having one end pivotally coupled to a lower end of a lateral side of the upper connecting block  21  and another end pivotally coupled, together with a corresponding lower horizontal member  26 , to the lower end portion of a corresponding rear leg tube  13 . With the second collapsing auxiliary assembly  20  described above, the lateral sides of the frame  1  may be moved toward each other more smoothly during the collapsing operation of the stroller. 
         [0038]    Next, the structure of the collapsing operation unit  5  will be described with reference to  FIGS. 2 and 3 . The collapsing operation unit  5  mainly includes a deformable actuating member  52  and two locking members  53  each being pivotally coupled to one end of the actuating member  52 . In the embodiment illustrated in  FIGS. 2 and 3 , the actuating member  52  consists of three portions, namely an intermediate portion  521  and two connecting portions  522  each having a first end pivotally coupled to one end of the intermediate portion  521  and a second end pivotally coupled to a corresponding locking member  53 . Each locking member  53  has a locking hook  531  formed at one end thereof that is opposite to the end coupled to the connecting portion  522 . The locking hook  531  has a guiding face  532  inclined from a front end toward a rear end of the locking hook  531  and a substantially planer engaging face  533 . Each locking member  53  is movably fitted to a rear end of a corresponding seat side-tube  42 . A biasing means (not shown) is disposed between the locking member  53  and the rear end of a corresponding seat side-tube  42  for biasing the locking member  53  toward the seat side-tube  42  such that when the seat side-tube  42  is supported on the seat tube supporting member  41 , the engaging face  533  of the locking hook  531  of the locking member  53  engages with a bottom of the seat tube supporting member  41  to thereby lock the seat side-tube  42  to the seat tube supporting member  41  (see  FIG. 2 ). 
         [0039]      FIGS. 4   a - 4   d  are drawings illustrating the structure of the handle tube adjusting means  17 , wherein  FIG. 4   a  is an exploded perspective of the handle tube adjusting means  17 ;  FIG. 4   b  is an assembled perspective view of the handle tube adjusting means  17 ;  FIGS. 4   c  and  4   d  are cross-sectional views showing the locked state and unlocked state of the handle tube adjusting means  17  respectively. As shown in  FIG. 4   a , the handle tube adjusting means  17  mainly includes a hollow cylindrical main body  171 , a substantially U-shaped spring member  174  and two setting plastic members  178 . A protruding portion  172  is formed on an outer face of a peripheral wall of the main body  171  and a cut-out is formed in the peripheral wall of the main body  171  partially surround the protruding portion  172  such that a portion of the peripheral wall of the main body  171  that contains the protruding portion  172  forms a spring member. A resilient pressing portion  173  is formed at a first end of the main body  171  and it extends downwardly from the first end of the main body  171 . A hole  176  is formed in the peripheral wall of the main body  171  at a position corresponding to the resilient pressing portion  173 . An engaging protrusion  175  is protruding outwardly from a free end of the substantially U-shaped spring member  174 . 
         [0040]    In assembly, the main body  171  is firstly fitted onto the end of the handle tube  16  which is to be connected to the front leg tube  12 . A hole  161  is formed in the tube wall of the handle tube  16  at a position corresponding to the protruding portion  172  and another hole  162  is formed in the tube wall of the handle tube  16  at a position corresponding to the hole  176  in the peripheral wall of the main body  171  and the resilient pressing portion  173  (see  FIGS. 4   c  and  4   d ). Next, the substantially U-shaped spring member  174  is put into the handle tube  16  until its engaging protrusion  175  align and engage with the hole  162  of the handle tube  16  and the hole  176  of the main body  171 . Then, the setting plastic members  178  are installed to the handle tube  16  to become the state shown in  FIG. 4   b . Next, with the engaging protrusion  175  being pressed down, the handle tube  16 , on which the handle tube adjusting means  17  is installed, is inserted in the front leg tube  12  until the protruding portion  172  of the main body  171  and the engaging protrusion  175  of the spring member  174  align and engage with the holes  121  and  122  formed in the tube wall of the front leg tube  12  respectively so as to connect the handle tube  16  to the front leg tube  12  as shown in 
         [0041]    
       FIG. 4 
       c.  
     
         [0042]    When the handle tube  16  needs to be further received in the front leg tube  12 , the resilient pressing portion  173  is pressed down to cause the engaging protrusion  175  of the spring member  174  to disengage from the hole  122  of the front leg tube  122  and the hole  176  of the main body  171  and thus allow the handle tube  16  to be slide further into the front leg tube  12 . Additionally, in order to limit the length that the handle tube  16  may be inserted into the front leg tube  12 , one or more recess portions  123  may be formed on the tube wall of the front leg tube  12  at positions a distance from the tube end of the front leg tub  12 . 
         [0043]    Next, a collapsing operation of the stroller according to the first embodiment of the present invention will be describe with reference to  FIGS. 5   a - 5   c.    
         [0044]    A fully extended state of the stroller is illustrated in  FIG. 5   a  and in this state the two seat side-tubes  42  of the seat unit  4  are in a locked state with the seat tube supporting members  41  as shown in  FIG. 2 . When the stroller needs to be collapsed, user only needs to hold the intermediate portion  521  of the actuating member  52  of the collapsing operation unit  5  with his hand and pull backward to cause the locking members  53 , which are pivotally coupled to the actuating members  52 , to slide backward to disengage the locking members  53  from the corresponding seat tube supporting members  41 . Then, as shown in  FIG. 5   b , pulling the actuating member  52  upward to cause the two seat side-tubes  42  to rotate upwardly about the coupling points that they coupled to the front leg tubes  12 . At this time, because the front end of the first linking-up members  34  pivotally coupled to the seat side-tubes  42 , this upward rotation movement of the seat side-tubes  42  will cause the front end of the first linking-up members  34  that are coupled to the seat side-tubes  42  to move closer to the front leg tubes  12 . Additionally, the rear end of the first linking-up members  34  rotate downwardly because the rear end of the first linking-up members  34  pivotally coupled to the seat tube supporting members  41  that are fixed to the rear leg tubes  13  and the weight of the rear wheels  15  exerts on the rear leg tubes  13 , and this will cause the rear leg tubes  13  to move toward the front leg tubes  12  to thereby allow the stroller to collapses in the front/rear direction. 
         [0045]    Additionally, because the second linking-up members  37  are coupled between the first linking-up members  34  at a position closer to the seat tube supporting members  41  and the upper horizontal members  24  of the second collapsing auxiliary assembly  20 , this downward rotation movement of the first linking-up members  34  will cause the end of the upper horizontal members  24  that coupled to the rear leg tubes  13  to move downward and the end of the upper horizontal members  24  that coupled to the upper connecting block  21  to move upward, and thus cause the rear leg tubes  13  to move toward each other with the help of the guiding tube  22  of the second collapsing auxiliary assembly  20 . Moreover, because the rear leg tubes  13  are connected to the front leg tubes  12  respectively, this collapsing movement of the rear leg tubes  13  toward each other will cause the front leg tubes  12  to move toward each other as well. Additionally, because the front end of the crossing tubes  33  of the first collapsing auxiliary assembly  3  is respectively coupled to the front leg tubes  12  and the rear end thereof is respectively coupled the seat side-tubes  42 , this collapsing movement of the front leg tubes  12  toward each other will cause the front ends of the crossing members  33  to close to each other and in turn cause the seat side-tubes  42  to close to each other through a scissor-like movement of the crossing members  33 , and further cause the two connecting portions  522  that coupled to the intermediate portion  521  of the actuating member  52  of the collapsing operation unit  5  to pivot inwardly and become parallel to each other, and allow the stroller to be collapsed in width direction. After that, the handle tubes  16  may be retracted into the front leg tubes  12  by operating the he handle tube adjusting means  17  to reduce the dimension in height direction. Then, the collapsed stroller may be maintained in this fully collapsed state by engaging a first fastening member  11  provided on the rear leg  13  to a second fastening member  19  provided on the front leg tube  12 , as shown in  FIG. 5   c.    
         [0046]    When need to use the stroller, the user only needs to disengage the first fastening member  11  from the second fastening member  19  to release the front leg tubes  12  from the rear leg tubes  13 , push the collapsing operation unit  5  backward and downward to make the front leg tubes  12  and the rear leg tubes  13  to move away from each other and allow the stroller to expand in the front/rear direction, and step on the lower connecting block  23  of the second collapsing auxiliary assembly  20  downwardly with his leg to expand the upper horizontal members  24  and lower horizontal members  26  of the second collapsing auxiliary assembly  20  laterally so as to allow the stroller to expand in the width (lateral) direction and cause the stroller to return to the fully expanded state as illustrated in  FIG. 1 , in which state the locking members  53  of the collapsing operation unit  5  are once again in lock with the seat tube supporting members  41 . 
         [0047]    Next, a stroller according to a second embodiment of the present invention will be described with reference to  FIGS. 6-8 , in which  FIG. 6  is a schematic perspective view of the stroller according to the second embodiment;  FIG. 7  is an enlarged perspective view of the collapsing operation unit  5 ′ according to the second embodiment;  FIGS. 8   a  and  8   b  are partially cut away enlarged perspective views of the collapsing operation unit  5 ′ showing the collapsing operation unit  5 ′ in a locked and unlocked states respectively. 
         [0048]    Because the main differences between the first and the second embodiments reside in the design of the collapsing operation unit  5 ′ and the back-rest of the seat unit, only the differences between the first and the second embodiments are described in the following description and for the structures that are the same in both the first and second embodiments will be omitted for simplicity. Additionally, same reference numerals will be used in  FIGS. 6-8  for components of the second embodiment that are the same as those of the first embodiment. 
         [0049]    As shown in the drawings, the collapsing operation unit  5 ′ of this embodiment mainly comprises a one-piece actuating member  52 ′ and two cylindrical shaped locking members  53 ′ each fixed to one end of the actuating member  52 ′ respectively. In this embodiment, the one-piece actuating member  52 ′ is made of flexible plastic material. Two longitudinal elongated openings  54  are formed in the peripheral wall of each of the locking members  53 ′ at radically symmetrical positions and a locking hook  531 ′ extending downwardly from the peripheral wall wherein a planer horizontal engaging face  533 ′ is formed at the hook end of the locking hook  531 ′. One collapsing operation unit  5 ′ of this embodiment is operably mounted to each of the seat side-tubes  42  by mounting a locking members  53 ′ to a rear end of the seat side-tube  42  and passing a rivet  56  through two longitudinal elongated openings  54  of the locking member  53 ′ and the seat side-tube  42 . Additionally, a core spring  55  is disposed in the locking member  53 ′ and fitted on the seat side-tube  42  between the rivet  56  and an end wall of the cylindrical shaped locking members  53 ′ as shown in  FIG. 8   a  to thereby form a biasing means so that when the seat side-tube  42  is supported on the seat tube supporting member  41 ′, the engaging face  533 ′ of the locking hook  531 ′ of the locking member  53 ′ engages with the bottom of the seat tube supporting member  41 ′ to thereby lock the seat side-tube  42  to the seat tube supporting member  41 ′, as shown in  FIG. 8   a.    
         [0050]    The other difference between this embodiment and the first embodiment is the backrest of the seat unit. As shown in  FIG. 6 , two crossing members  45  are pivotal collapsibly provided between the two backrest tubes  44  to provide additional mechanical strength to the backrest and to facilitate the collapsing movement of the two backrest tubes  44  during the collapsing operation of the stroller. 
         [0051]    Because the first collapsing auxiliary assembly of the embodiment is the same as the first collapsing auxiliary assembly  3  of the first embodiment, thus when needs to collapse the stroller of this embodiment, the user only needs to hold the actuating member  52 ′ of the collapsing operating unit  5 ′ and pull it backward to cause the locking member  53 ′ that connected to the actuating member  52 ′ to slide backward to disengage the locking member  53 ′ from the seat tube supporting member  41 ′ (see  FIG. 8   b ), and then pull the actuating member  52 ′ upward to execute a collapsing operation the same as that of the first embodiment described above to collapse the stroller. 
         [0052]    Although the present invention has been described above according to the preferred embodiment thereof, this does not mean that the scope of the present invention is limited to specific structure described above. It will be apparent to people skilled in this art that many modifications can be made to the disclosed structures without departing from the scope of the invention. Therefore, it is the intent of the appended claims to cover all such variations and modifications as come within the sprit and scope of this invention.