Abstract:
A bi-directional safety lock structure for strollers folding single-handedly has a sliding element located above a depressing element to prevent the depressing element from moving and the single-handed operation structure from releasing in normal conditions. When releasing the constraint, the sliding element may be moved leftwards or rightwards to release the depressing element. Thus the structure is suitable for users of different hand using habits and improves operation convenience.

Description:
FIELD OF THE INVENTION  
         [0001]    The invention relates to a bi-directional safety lock structure for strollers folding single-handedly to enable users to selectively release the single-handed folding structure leftwards or rightwards.  
         BACKGROUND OF THE INVENTION  
         [0002]    Strollers generally may be extended to a usage state and collapsed to a folding state. When folding the stroller from the usage state to the folding state, the baby sitting in the stroller has to be taken out before the folding structure may be operated. In the event that the baby is still not capable of standing alone or walking, the user often has to hold the baby with one hand and operate the folding structure with the other hand, which is inconvenient. To remedy this problem, strollers that are foldable single-handedly have been developed. References can be found in U.S. Pat. No. 6,068,284 and R.O.C. publication No. 262689. In those structures, the frame collapses to the folding state after the operating structure is released. In order to prevent improper operations that result in accidental collapsing of the frame and cause injury to the baby sitting in the stroller, the conventional single-handed operation structures usually have a safety lock. The safety lock has to be released before the single-handed operation structure is actuated to release the frame. However, the commonly used safety locks can be released by operating in only one direction, and they are mostly designed to be operated by the thumb. When users have to hold the baby or goods with one hand and release the safety lock with the other hand, it is awkward and inconvenient. Sometimes users have to switch hands for holding the baby or goods, and use the other hand to release the unidirectional safety lock. This is a cumbersome operation.  
         SUMMARY OF THE INVENTION  
         [0003]    The object of the invention is to provide a bi-directional safety lock structure to resolve the problems occurring with the conventional safety locks of single-handed folding mechanisms that can be operated only in one direction. The invention mainly has a sliding element that is slidable reciprocally in a transverse flute. The sliding element may be released by moving rightwards or leftwards to release the constraint on a depressing element and thereby actuate a release mechanism. As the sliding element may be moved rightwards or leftwards, it is more convenient for use. Thus accidental collapsing of the stroller may be avoided.  
           [0004]    The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings. The description and drawings are only to serve for reference and illustrative purposes, and are not intended to limit the scope of the invention. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]    [0005]FIG. 1 is a schematic view of a conventional stroller.  
         [0006]    [0006]FIG. 2 is a schematic view of the invention adopted on a stroller.  
         [0007]    [0007]FIG. 3 is a perspective view of the invention.  
         [0008]    [0008]FIG. 4 is a fragmentary schematic view of the invention showing the joint set in a first embodiment.  
         [0009]    [0009]FIG. 5 is a fragmentary schematic view of the invention showing the joint set in a second embodiment.  
         [0010]    [0010]FIG. 6 is an exploded view of a canvas bracket set partly cut away.  
         [0011]    [0011]FIG. 7 is a schematic view of the rear support rack in an operating condition. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0012]    Refer to FIGS. 1, 2 and  3  for a first embodiment of the invention. The bi-directional safety lock structure  5  for strollers folding single-handedly is mainly installed on a stroller frame  2 , which can be folded single-handedly. The frame  2  includes a handle tube  21 , front leg tubes  22 , rear leg tubes  23 , a seat tube  24 , a pair of joint sets  3 , a release mechanism  4  for releasing the joint sets  3  and a bi-directional safety lock structure  5  that pivotally engages with one another. The joint sets  3  mainly control folding and latching of various tubes. Through the release mechanism  4  (in this embodiment the release mechanism is a linkage bar driving linkage members located on two sides) the joint sets  3  located on two sides of the frame  2  may be driven and released to collapse the frame in a folding state (as shown in FIG. 5).  
         [0013]    The bi-directional safety lock  5  mainly includes an element anchor dock  51 , a depressing element  52  and a sliding element  53 . In this embodiment the element anchor dock  51  is a serving tray which has at least a longitudinal flute  511  and a transverse flute  512 .  
         [0014]    The depressing element  52  is slidably located in the longitudinal flute  511  of the element anchor dock  51 . The depressing element  52  is connected to the release mechanism  4  and has an operating section  54  for an operator to depress and actuate the release mechanism  4  and release the joint sets  3  to achieve the folding function. In addition, the depressing element  52  has an outer protruding section  55  extending upwards. The outer protruding section  55  in this embodiment is a ridge.  
         [0015]    The sliding element  53  is located above the depressing element  52  and is housed in the middle portion of the transverse flute  512  of the element anchor dock  51 . The sliding element  53  has a bucking section  56  extending downwards corresponding to the outer protruding section  55  (formed in a strut in this embodiment). In normal conditions, the bucking section  56  of the sliding element  53  is in contact with the outer protruding section  55  of the depressing element  52  through an elastic element (not shown in the drawing) to prevent the depressing element  52  from moving and thereby prevent the frame  2  from accidentally collapsing. When releasing, the sliding element  53  may be moved leftwards or rightwards. The outer protruding section  55  of the depressing element  52  is free from the harness of the bucking section  56  of the sliding element  53 , thus the depressing element  52  may be moved in the longitudinal flute  511  of the element anchor dock  51  (as shown in FIG. 4), and the release mechanism  4  may be driven to fold the frame.  
         [0016]    Refer to FIGS. 5, 6 and  7  for a second embodiment of the invention. The bi-directional safety lock of the invention mainly includes an element anchor dock  6 , a depressing element  7  and a sliding element  8 . The element anchor dock  6  is a shell mounted onto the handle tube  21  and has a first sliding flute  61  and a second sliding flute  62 .  
         [0017]    The depressing element  7  is slidably housed in the first sliding flute  61  of the element anchor dock  6 . The depressing element  7  is connected to a release mechanism  9  (consisting of two L-shaped driving plates pivotally engaging with one another and movable interactively in this embodiment) and has an operating section  71  to enable users to actuate the release mechanism  9  and release the joint sets  3  of the frame to achieve the folding function. In addition, the depressing element  7  has two recesses  72  interposed by an outer protrusive section  73 , which extends upwards to form a ridge.  
         [0018]    The sliding element  8  is located above the depressing element  7  and is housed in the middle portion of the second sliding flute  62  of the element anchor dock  6 . The sliding element  8  has a bucking section  81  extending downwards corresponding to the outer protruding section  73  of the depressing element  7 . In normal conditions, the bucking section  81  of the sliding element  8  is in contact with the outer protruding section  73  of the depressing element  7  through an elastic element to prevent the depressing element  7  from moving and thereby prevent the frame  2  from accidentally collapsing. When releasing, the sliding element  8  may be moved leftwards or rightwards. The outer protruding section  73  of the depressing element  7  is free from the harness of the bucking section  81  of the sliding element, thus the depressing element  7  may be moved in the first sliding flute  61  of the element anchor dock  6  and the release mechanism  9  may be driven to fold the frame  2 .  
         [0019]    By means of the construction set forth above, the bi-directional safety lock structure for strollers folding single-handedly according to the invention provides a sliding element movable leftwards or rightwards to enable users to release the safety mechanism and fold the stroller frame conveniently.  
         [0020]    While the preferred embodiments of the invention have been set forth for the purpose of disclosure, modifications of the disclosed embodiments of the invention as well as other embodiments thereof may occur to those skilled in the art. Accordingly, the appended claims are intended to cover all embodiments which do not depart from the spirit and scope of the invention.