Patent Publication Number: US-2016230804-A1

Title: Snap Hook

Description:
BACKGROUND OF INVENTION 
     1. Field of Invention 
     The present invention relates to a snap hook and, more particularly, to a reliable snap hook. 
     2. Related Prior Art 
     As disclosed in U.S. Pat. No. 5,896,630, a snap hook  1  includes a body, a gate keeper  8  for closing an opening  7  made by the body, a first locking means for locking the gate keeper  8 , and a second locking means  17  for locking the first locking means. The body includes a shank  2  and an arched portion  3  formed at an end of the shank  2 . The gate keeper  8  is formed with two locking tabs  15 . The first locking means includes a locking lever  11  pivotally connected to the shank  2 . The locking lever  11  includes two locking arms  14  and a slot  21 . The second locking means  17  includes a slide plate  18  and a pin  20 . The pin  20  is inserted in the slot  21 . The slide plate  18  includes two tabs  23  on a side. An internal spring  13  is place against another side of the slide plate  18  to force the tabs  23  towards the locking lever  11 . 
     The pin  20  is operable to cause an end of the slide plate  18  to extend beyond the locking lever  11 . The end of the slide plate  18  is kept in position as the tabs  23  are located against a closed end of the slot  21  and an end of the locking lever  11 . The slide plate  18  prevents the locking lever  11  from pivoting relative to the body. The locking arms  14  abut against the locking tabs  15 . Thus, the gate keeper  8  cannot be pivoted. 
     The pin  20  can be operated to move the end of the slide plate  18  under the locking lever  11  to allow the locking lever  11  to pivot relative to the body. However, the pin  20  must be pressed down relative to the locking lever  11  to disengage the tabs  23  from the end of the locking lever  11  and the closed end of the slot  21 . Then, the pin  20  can be moved along the locking lever  11  to move the end of the slide plate  18  under the locking lever  11  to allow the locking lever  11  to pivot. The locking arms  14  are disengaged from the locking tabs  15 . Thus, the gate keeper  8  can be pivoted. 
     As disclosed in U.S. Pat. No. 8,752,254, a snap hook  100  includes a locking member  200  located in a gate  400 . However, it is difficult to insert the locking member  200  in the gate  400  since the gate  400  is small. It is also difficult to maneuver the locking member  200  because the gate  400  is small. 
     The present invention is therefore intended to obviate or at least alleviate the problems encountered in prior art. 
     SUMMARY OF INVENTION 
     It is the primary objective of the present invention to provide a reliable and convenient snap hook. 
     To achieve the foregoing objectives, the snap hook includes an arched body, a gate, a lock and a security device. The arched body includes an opening and a cutout. The gate is pivotally connected to the arched body between a closing position to close the opening and an opening position to open the opening. The lock is pivotally connected to the arched body between a locking position to avoid pivoting of the gate into the opening position from the closing position and a releasing position to allow the gate to pivot into the opening position from the closing position. The security device includes a switch movably mounted on the lock between a first position and a second position and a tongue extending from the switch. The tongue abuts the arched body to avoid pivoting of the lock into the releasing position from the locking position when the switch is in the first position. The tongue is allowed to enter the cutout to allow the lock to pivot into the releasing position from the locking position when the switch is in the second position. 
     Other objectives, advantages and features of the present invention will be apparent from the following description referring to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The present invention will be described via detailed illustration of the preferred embodiment referring to the drawings wherein: 
         FIG. 1  is a perspective view of a snap hook according to the preferred embodiment of the present invention; 
         FIG. 2  is an exploded view of the snap hook shown in  FIG. 1 ; 
         FIG. 3  is an enlarged perspective view of an arched body of the snap hook shown in  FIG. 1 ; 
         FIG. 4  is an enlarged perspective view of a locking element of the snap hook shown in  FIG. 1 ; 
         FIG. 5  is an enlarged perspective view of security element connected to the arched body of the snap hook shown in  FIG. 4 ; 
         FIG. 6  is a cross-sectional view of the snap hook shown in  FIG. 1 ; 
         FIG. 7  is a cross-sectional view of the snap hook in another position than shown in  FIG. 6 ; and 
         FIG. 8  is a cross-sectional view of the snap hook in another position than shown in  FIG. 7 . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENT 
     Referring to  FIG. 1 , a snap hook  100  includes an arched body  10 , a gate  30 , a lock  40  and a security device  50  according to the preferred embodiment of the present invention. The gate  30  is used to close the arched body  10 . The lock  40  is used to lock the gate  30 . The security device  50  is used to restrain the lock  40 . 
     Referring to  FIGS. 2 and 3 , the arched body  10  includes a first end  13 , a second end (not numbered), a middle section  11  between the first end  13  and the second end, and an opening  19  between the first end  13  and the middle section  11 . The arched body  10  further includes an aperture  14  near the second end. The arched body  10  further includes an internal edge  16  directed to the opening  19  and an external edge  17  opposite to the internal edge  16 . The arched body  10  further includes, in the vicinity of the first end  13 , two recesses  12  in the internal edge  16  and a fin  18  at the internal edge  16 . The recesses  12  are separated from each other by the fin  18 . 
     The arched body  10  further includes three recesses  20 ,  22  and  21  in the external edge  17 . The recess  22  is deeper than the recess  20 . The recess  21  is deeper than the recess  22 . The arched body  10  further includes two apertures  23  and  24 . 
     Referring to  FIG. 2 , the gate  30  includes a front strip  31  extending between two lateral strips  34  extending parallel to each other. Each lateral strip  34  is in the form of a long triangle. Each lateral strip  34  includes a corner (the “first corner”) far from two other corners (the “second corner” and the “third corner”) between which an edge  35  extends. Each lateral strip  34  further includes an aperture  36  near the second corner and another aperture  37  near the third corner. The front strip  31  includes a first end  32  between the first corners of the lateral strips  34  and a second end (not numbered) between the second corners of the lateral strips  34 . A cutout  33  is made in the first end of the front strip  31 . 
     A fastener  28  is inserted in the apertures  36  of the lateral strips  34  and the aperture  24  of the arched body  10 . Thus, the gate  30  is pivotally connected to the arched body  10 . The fastener  28  is a threaded bolt, a pin, a rivet or any other proper element. The first end of the front strip  31  is located in the vicinity of the first end  13  of the arched body  10 . A torque spring  26  is supported on the fastener  28 . The torque spring  26  biases the first end of the front strip  31  towards the first end  13  of the arched body  10   
     Referring to  FIGS. 2 and 4 , the lock  40  includes a back strip  41  extending between lateral strips  42  extending parallel to each other. The back strip  41  includes two slots  54  and a tab  57  between the slots  54 . The tab  57  is preferably made of a portion of the back strip  41  that is punched out of one of the slots  54 . The tab  57  preferably includes a section extending perpendicular to the back strip  41  and another section extending parallel to the back strip  41 . 
     Each lateral strip  42  includes a first end  43 , a second end  45  opposite to the first end  43 , an aperture  44  near the first end  43 , and a slot  46  near the second end  45 . The slot  46  includes a transverse section  47  and a longitudinal section  48 . The terms, “transverse” and “longitudinal”, are given with reference to the lock  40 . The longitudinal section  48  of the slot  46  extends in an arched manner. The first ends  43  of the lateral strips  42  extend beyond a first end of the back strip  41  and the second ends  45  of the lateral strips  42  extend beyond a second end of the back strip  41 . 
     A fastener  27  is inserted in the apertures  44  of the lock  40  and the aperture  23  of the arched body  10 . Thus, the lock  40  is pivotally connected to the arched body  10 . The fastener  27  is a threaded bolt, a pin, a rivet or any other proper element. Another torque spring  25  is supported on the fastener  27 . The torque spring  25  tends to pivot the lock  40  away from the arched body  10 . 
     A pin  29  is inserted in the slots  46  of the lock  40  and the apertures  37  of the gate  30 . Thus, the lock  40  is pivotally connected to the gate  30 . The pin  29  is a threaded bolt, a pin, a rivet or any other proper element. Thus, the pin  29  is moved along the slots  46  when the lock  40  is pivoted relative to the gate  30 . 
     Referring to  FIGS. 2, 4 and 5 , the security device  50  includes a switch  51 , a tongue  55 , and a spring  58 . Tongue  55  extends from the switch  51  transversely. The switch  51  is located on a side of the back strip  41 . Two fasteners  53  are used to movably locate the switch  51  on the lock  40  between a first position and a second position. Each of the fasteners  53  includes a body and an enlarged head. The heads of the fasteners  53  are placed on an opposite side of the back strip  41 . The bodies of the fasteners  53  are movable along the slots  54 . The bodies of the fasteners  53  are inserted in two apertures  52  made in the switch  51 . The tongue  55  is also inserted in one of the slots  54 . A compression spring  58  is compressed between the tongue  55  and the tab  57 . The compression spring  58  biases the tongue  55  away from the tab  57 . The tongue  56  preferably includes a bore for receiving an end of the compression spring  58 . 
     In operation, a section of a rope (not shown) is inserted through the aperture  14  near the second end of the arched body  10 . The gate  30  can be pivoted between a closing position as shown in  FIG. 6  and an opening position as shown in  FIG. 8 . The lock  40  can be pivoted between a locking position as shown in  FIG. 6  and a releasing position as shown in  FIGS. 7 and 8 . The switch  51  can be moved between a first position as shown in  FIG. 6  and a second position as shown in  FIGS. 7 and 8 . 
     Referring to  FIG. 6 , the gate  30  is located in the locking position. The lock  40  is located in the locking position. The switch  51  is located in the first position. The recess  20  of the arched body  10  receives the tip of the tongue  55 . The switch  51  keeps the lock  40  in the locking position. An edge of the transverse section  47  of the slot  46  of each lateral strip  42  abuts against the pin  29 . Thus, the lock  40  keeps in the gate  30  in the closing position. That is, the locks  40  keeps the first end  32  of the front strip  31  of the gate  30  against the first end  13  of the arched body  10 . The fin  18  is inserted in the cutout  33  to keep the gate  30  in position laterally relative to the first end  13  of the arched body  10 . 
     Referring to  FIG. 7 , the switch  51  is located in the second position. The tongue  55  is allowed to enter the recess  22  to allow the lock  40  to pivot into the releasing position from the locking position. 
     Referring to  FIG. 8 , the switch  51  is located in the second position. The tongue  55  is inserted in the recess  22 . The lock  40  is pivoted into the releasing position from the locking position. The gate  30  is pivoted into the opening position from the closing position. 
     The present invention has been described via the detailed illustration of the preferred embodiment. Those skilled in the art can derive variations from the preferred embodiment without departing from the scope of the present invention. Therefore, the preferred embodiment shall not limit the scope of the present invention defined in the claims.