Patent Publication Number: US-6712484-B2

Title: Ratchet wrench and lighting circuit

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to wrenches, and more specifically, to a ratchet wrench and lighting circuit arrangement, which enables the user to replace the lamp bulb or battery of the lighting circuit assembly easily. 
     FIG. 1 shows a lighting circuit assembly installed in a ratchet driving member for ratchet wrench according to the prior art. As illustrated, the ratchet driving member has a stepped center through hole. The lighting circuit assembly is installed in the stepped center through hole of the ratchet driving member, comprised of a lamp socket holding a lamp bulb, a metal conical spring, a mercury battery, a metal contact plate, and a switch. This arrangement is not durable in use because the parts of the lighting circuit assembly tend to be forced out of position when operating the ratchet wrench. In case the lamp bulb is damaged or the battery power of the mercury battery is low, it is difficult to remove the lighting circuit assembly from the ratchet driving member for a replacement. Further, when the socket coupled to the shaft of the ratchet driving member and attached to the workpiece, the light passage is blocked. 
     SUMMARY OF THE INVENTION 
     The present invention has been accomplished to provide a ratchet wrench and lighting circuit arrangement, which eliminates the aforesaid drawbacks. It is one object of the present invention to provide a ratchet wrench and lighting circuit arrangement, which is easy to install. It is another object of the present invention to provide a ratchet wrench and lighting circuit arrangement, which enables the user to replace the lamp bulb or the battery conveniently. It is still another object of the present invention to provide a ratchet wrench and lighting circuit arrangement, which provides good illumination when mounted with the socket and attached to the workpiece. According to one aspect of the present invention, the ratchet wrench and lighting circuit arrangement comprises a ratchet wrench, the ratchet wrench having a hollow ratchet driving member mounted in a box at one end thereof and a socket detachably coupled to the ratchet driving member, a holder shell fitted into the ratchet driving member and detachably secured thereto by a screw joint, and a lighting circuit assembly installed in the holder shell and controlled to emit light through a lens at a bottom side of the ratchet driving member. According to another aspect of the present invention, the socket has transverse through holes through which light passes to the outside of the socket when the socket coupled to the ratchet driving member and attached to the workpiece. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a sectional view showing a lighting circuit assembly installed in a ratchet driving member for a ratchet wrench according to the prior art. 
     FIG. 2 is an elevational view of the present invention before the connection of the socket to the ratchet driving member. 
     FIG. 3 is an exploded view of the present invention. 
     FIG. 4 is a sectional view of the present invention. 
     FIG. 5 is a sectional view of an alternate form of the present invention. 
     FIG. 6 illustrates the outer appearance of the socket according to the present invention. 
     FIG. 7 shows the lever fastened to one transverse through hole of the socket according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIGS. from  2  through  6 , a ratchet wrench and lighting circuit arrangement in accordance with the present invention is generally comprised of a ratchet driving member  10 , a lighting circuit assembly  20 , a holder shell  30 , and a socket  40 . 
     The ratchet driving member  10  is a hollow stepped member mounted in the box of a wrench body (not shown) having a ratchet wheel  12 , a polygonal shaft  11  axially extended from one side of the ratchet wheel  12 , a stepped through hole  13  axially extended through the ratchet wheel  12  and the polygonal shaft  11 , a lens  14  fixedly fastened to the polygonal shaft  11  at one end of the stepped through hole  13 , and an inner thread  131  in the ratchet wheel  12  around the other end of the stepped through hole  13 . 
     The lighting circuit assembly  20  is comprised of a lamp bulb  21 , a metal contact plate  22 , a mercury battery  23 , and a switch  24 . 
     The holder shell  30  fits the stepped through hole  13  of the ratchet driving member  10 , having an axially extended open chamber  31 , which holds the lighting circuit assembly  20 , and an outer thread  32  threaded into the inner thread  131  of the ratchet driving member  10 . Alternatively, a magnetic member  33  can be fixedly provided at a part of the holder shell  30 , so that the holder shell  30  is secured in position by magnetic attraction when inserted into the stepped through hole  13  of the ratchet driving member  10  (The ratchet driving member  10  is made of metallic material attractive to magnet). 
     The socket  40  has an axially extended polygonal coupling hole  41  coupled to the polygonal shaft  11  of the ratchet driving member  10 , and a plurality of transverse through holes  42  in communication with the axially extended polygonal coupling hole  41 . 
     The lighting circuit assembly  20  is installed in the axially extended open chamber  31  of the holder shell  30  before the assembling the ratchet wrench. When assembling the ratchet wrench, the holder shell  30  is directly fastened to the stepped through hole  13  of the ratchet driving member  10 . When the lamp bulb  21  is damaged, the holder shell  30  can easily be removed from the ratchet driving member  10  so that the user can replace the damaged lamp bulb  21 . 
     When switched on the switch  24 , light passes from the lamp bulb  21  through the lens  14  and then the transverse through holes  42  to the outside of the socket  40  to illuminate the working area around the workpiece. Further, the transverse through holes  42  may be respectively covered with a transparent or colored (acrylic) lens. 
     Referring to FIG. 7, a lever  43  may be inserted into one transverse through hole  42  of the socket  40  for turning the socket  40  and the workpiece with the hand. 
     A prototype of ratchet wrench and lighting circuit arrangement has been constructed with the features of FIGS.  2 ˜ 7 . The ratchet wrench and lighting circuit arrangement functions smoothly to provide all of the features discussed earlier. 
     Although a particular embodiment of the invention has been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.