Patent Publication Number: US-8117949-B2

Title: Movable wrench

Description:
BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     The invention relates to a movable wrench and, in particular, to a wrench that is convenient in performing reciprocal rotations. 
     2. Related Art 
     Traditionally, one needs to adjust a roller before using a movable wrench so that the holding opening between its fixed jaw and movable jaw matches with the size of a screw nut in order to rotate it. 
     However, when space is limited, it is difficult to hold the wrench and rotate the nut continuously. Instead, one has to loosen the roller to enlarge the holding opening and snap another two opposite surfaces of the nut. This is rather inconvenient. 
     To solve the above-mentioned problem, U.S. Pat. No. 3,022,689 discloses a wrench, as shown in  FIG. 7 . It includes a holder  66  for the user to hold. One end of the holder  66  has a fixed jaw  68 . One side of the fixed jaw  68  is provided with a movable jaw  62  that matches with a roller  61  and drives the movable jaw  62 . The roller  61  is urged by a compressible spring  64  to provide the elastic force for the movable jaw  62  to locally move back and forth. The middle section of the holder  66  has an arc elastic chip  65 . One end of the elastic chip  65  is fixed on the holder  66 . The bottom of the other end has a protruding part  651  and connects with a spring lock  63 . One end of the spring lock  63  extends to one side of the roller  61  and forms a stopping part  631 , stopping the roller  61  from further moving. This fixes the opening between the fixed jaw  68  and the movable jaw  62  for the convenience of rotation jobs. When one presses the elastic chip  65  on the middle section of the holder  66 , the blocking of the stopping part  631  of the spring lock  63  on the roller  61  is removed. The movable jaw  62  can freely move for the movable wrench to rotate reversely. 
     However, in practice, the movable wrench has the problems of unable to operate and incorrect touches. Please refer to  FIG. 8 . There is an obvious narrow long space  67  between the elastic chip  65  and the holder  66 . After a long time of use, it will accumulate dusts and debris from the environment. This will make the elastic chip  65  stuck and it cannot be effectively depressed for normal operations. 
     As shown in  FIGS. 7 and 8 , the elastic chip  65  and the spring lock  63  are thin and long plates, both exposed from the wrench surface. When an external force is imposed thereon, the elastic chip  65  or the spring lock  63  is likely to be deformed. Once either one of them is deformed, the movable wrench no longer works. 
     Moreover, as shown in  FIG. 9 , one holds the holder  66  to exert a force when using the wrench. However, as the elastic chip  65  is located on one side surface of the holder  66 , one may mis-trigger the elastic chip  65  when exerting a force. This is troublesome. 
     Moreover, the spring lock  63  is a long and thin plate. It connects to the elastic hip  65  by one end to support the stopping part  631  on the other end, so that the stopping part  631  can stop the roller  61 . Therefore, the stopping part  631  of the spring lock  63  has a limited stopping effect on the roller  61 . Once the wrench exerts a larger force on an object, the stopping part  631  of the spring lock  63  cannot stop the roller  61 . In that case, the movable jaw  62  can still freely move and the wrench cannot tightly lock the object. 
     SUMMARY OF THE INVENTION 
     An objective of the invention is to solve the above-mentioned problems by providing a movable wrench. By changing the configuration of the operating end and the operating space, it can prevent dusts and impurities from falling in between. So the invention does not stuck because of this. It thus has a longer lifetime. 
     Another objective of the invention is to provide a movable wrench in which most of the operating element is disposed in an inner groove. This prevents the wrench from deforming due to collisions when it is put away inappropriately, thereby elongating its lifetime. 
     Yet another objective of the invention is to provide a movable wrench in which the bottom surface of the operating element urge against the bottom surfaces of the accommodating cavity and the inner groove. The operating element does not need to sustain a large pressure alone. This avoids the deformation problem. 
     A further objective of the invention is to provide a movable wrench in which the operating space is on the connecting part and in the vicinity of the holder. As the user rotates it, his palm would not incorrectly touch the operating end. This ensures work safety. 
     To achieve the above-mentioned objectives, the invention includes: a fixed jaw, a connecting part, a holder, a movable jaw, a screw bar, a first compressible spring, and an operating element. The fixed jaw and the movable jaw correspond to each other. The connecting part connects the fixed jaw, the movable jaw, and the holder. The screw bar is disposed at the connecting part. The operating element is pivotally disposed on the connecting part near the holder. The operating element and the screw bar have a locking relation. When the user&#39;s palm holds the holder, he can use his thumb to depress the operating element, thereby achieving locking and positioning effects. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will become more fully understood from the detailed description given herein below illustration only, and thus is not limitative of the present invention, and wherein: 
         FIG. 1  is a three-dimensional exploded view of the invention; 
         FIG. 2  is a three-dimensional assembly view of the invention; 
         FIG. 3  is a side cross-sectional view of the connecting part in  FIG. 2 ; 
         FIG. 4  is a side schematic view of the wrench in  FIG. 3 , where the movable jaw moves downward and drives the screw bar to depress the first compressible spring as the wrench rotates; 
         FIG. 5  is a schematic view of the operating element as viewed from another perspective: 
         FIG. 6  is a schematic view of the escaping hook part when the operating end is depressed; 
         FIG. 7  is a planar view of a conventional wrench; 
         FIG. 8  is another planar view of the conventional wrench; and 
         FIG. 9  is a schematic view showing that the elastic chip of the wrench in  FIG. 8  is erroneously touched. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention will be apparent from the following detailed description, which proceeds with reference to the accompanying drawings, wherein the same references relate to the same elements. 
     Please refer to  FIG. 1 to 3 . The following embodiment is a movable wrench, which includes a fixed jaw  11 , a movable jaw  12 , a screw bar  41 , a first compressible spring  42 , a shaft  43 , an operating element  51 , a pin  52 , and a second compressible spring  53 . 
     One side of the fixed jaw  11  is extended with a connecting part  2 , which in turn is extended with a holder  3  away from the fixed jaw  11 . One side of the connecting part  2  under the fixed jaw  11  is formed with a sliding track  21 . In this embodiment, the sliding track  21  is formed with rectangular and round cross sections. The bottom surface of the connecting part  2  below the sliding track  21  is formed with an insertion opening  211 . 
     The inner side surface of the sliding track  21  that faces the holder  3  is formed with a roughly rectangular accommodating cavity  22 . Both side surfaces of the accommodating cavity  22  are penetrated through. The inner top and bottom surfaces of the accommodating cavity  22  are formed with a firs through hole  221  and a second through hole  222  whose diameter is larger than that of the first through hole  221 . The second through hole  222  goes to the bottom surface of the connecting part  2 . 
     From the sidewall of the bottom surface of the accommodating cavity  22  toward the holder  3  is extended with a narrow and long inner groove  23 . The inner top and bottom surfaces of the inner groove  23  are respectively formed with a third through hole  231  and a fourth through hole  232 , which correspond to each other. A round operating space  24  is formed on the end of the inner groove  23  away from the accommodating cavity  22 . The operating space  24  is formed with an urging wall  241  along the longitudinal side surface. In this embodiment, the operating space  24  is located on the connecting part  2  and in the vicinity of the holder  3 . 
     The movable jaw  12  is accommodated in the sliding track  21  via the insertion opening  211 . It corresponds to the fixed jaw  11 . The inner side of the movable jaw  12  has a long saw section  121  in the vicinity of one side of the accommodating cavity  22 . 
     The screw bar  41  is disposed in the accommodating cavity  22 . The top and bottom surfaces  411  of the screw bar  41  are penetrated through. The body of the screw bar has a thread section  412  that matches with the saw section  121  of the movable jaw  12 . 
     The first compressible spring  42  goes below the connecting part  2 . In this embodiment, the first compressible spring  42  goes into the second through hole  222 . The top end of the first compressible spring  42  urges against the inner side of the bottom surface  411  of the screw bar  41 . 
     The shaft  43  penetrates from the second through hole  222  under the connecting part  2 . The shaft  43  goes through the first compressible spring  42  and the screw bar  41  in sequence and positions at the first through hole  221 . The bottom end of the shaft  43  has a locking part  431 , whose outer thread matches with the inner thread on the inner edge of the second through hole  222 . The bottom end of the first compressible spring  42  urges against the locking part  431 . 
     Most of the operating element  51  is disposed in the inner groove  23 . The bottom surface of the operating element  51  urges against the bottom surfaces of the accommodating cavity  22  and the inner groove  23  as a support. The middle section of the operating element  51  has a connecting hole  511  corresponding to the third through hole  231  and the fourth through hole  232 . Both ends of the operating element  51  have an operating end  512  and a locking end  513 , respectively. The bottom part of the operating end  512  has a concave hole  514 . The operating end  512  is round and located in the round operating space  24  to keep dusts and impurities out. In this embodiment, the operating end  512  slightly protrudes from the opening of the operating space  24  for depressing. 
     The locking end  513  is near the bottom surface of the accommodating cavity  22 . It has a hook part  513 A whose top surface urges against the bottom surface  411  of the screw bar  41  near its outer side and surrounds the outer side of the first compressible spring  42 . 
     The pin  52  goes from underneath the inner groove  23  of the connecting part  2  through the operating part  51 . In this embodiment, the pin  52  penetrates in sequence through the fourth through hole  232 , the connecting hole  511 , and the third through hole  231  to position the operating element  51 . The operating element  51  rotates with respect to the pin  52 . 
     The second compressible spring  53  is disposed in the operating space  24 . It bottom end urges against the urging wall  241 . The top end of the second compressible spring  53  urges against the bottom part of the operating end  512 . In this embodiment, the top end of the second compressible spring  53  urges against the concave hole  514  of the operating end  512  for positioning. 
     In practice, as shown in  FIG. 3 , a holding opening  13  is formed between the fixed jaw  11  and the movable jaw  12 . One can control the size of the holding opening  13  by rotating the screw bar  41  that in turn drives the movable jaw  12 . 
     Moreover, when rotating and fastening (loosening) the screw nut  14  (including other similar elements), the user holds the holder  3  by hand. The position of the hook part  513 A of the operating element  51  is as shown in  FIG. 4 . As the user holds and rotates, the screw bar  41  experiences a downward force due to the movable jaw  12 . The top surface of the hook part  513 A urges against the bottom surface  411  of the screw bar  41 . The bottom surface of the hook part  513 A urges against the bottom surfaces of the accommodating cavity  22  and the inner groove  23 . The support at these two places renders a more stable screw bar  41 , providing a better operating effect. 
     To rotate the wrench in reverse, the user uses his thumb to depress the operating end  512 . The hook part  513 A on the locking end  513  of the operating element  51  escapes from the bottom surface  411  of the screw bar  41 . The bottom surface  411  of the screw bar  41  is only urged by the first compressible spring  42 . Since the diagonal distance of the two opposite angles of the screw nut  14  is wider than the distance between the original two opposite holding surfaces, the holding opening  13  is pushed out by the two opposite angles during the reverse rotation. At the same time, the movable jaw  12  moves downward and drives the screw bar  41  to depress the first compressible spring  42 . When the wrench rotates to the other two opposite holding surfaces of the screw nut  14 , the distance between the two opposite holding surfaces of the screw nut  14  is narrower than the distance of the diagonal line between two opposite angles, the first compressible spring experiences a smaller force now. It thus pushes the screw bar  41  upward and drives the movable jaw  12  to reduce the holding opening  13 . In this case, the user removes his thumb from the operating end  512  of the operating element  51  to release the depressing state. The second compressible spring  53  in the operating space  24  then urges against the operating end  512 , so that the hook part  513 A on the locking end  513  of the operating element  51  returns to its original position. That is, the top surface of the hook part  513 A urges against the bottom surface  411  of the screw bar  41  again. These fastening and loosening processes are performed repeatedly to increase work efficiency. 
     In summary, in addition to the advantage of fast operations, the disclosed movable wrench has the following advantages as well: 
     1. The configuration of the operating end and the operating space is such that dusts and impurities are kept out. This prevents the invention from getting stuck and elongates its lifetime. 
     2. Most of the operating element is disposed in the inner groove. This prevents the operating element from being deformed due to collisions when one put away the movable wrench inappropriately. 
     3. The bottom surface of the operating element urges against the bottom surfaces of the accommodating cavity and the inner groove. The support from the bottom surfaces of the accommodating cavity and the inner groove prevents the operating element from experiencing too large a pressure and deformation. 
     4. The operating space is formed on the connecting part and in the vicinity of the holder. When the user rotates it, this space prevents the user&#39;s palm from erroneously touching the operating end, ensuring work safety. 
     Although the invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternative embodiments, will be apparent to people skilled in the art. Therefore, it is contemplated that the appended claims will cover all modifications that fall within the true scope of the invention.