Patent Publication Number: US-2005120833-A1

Title: Ratchet wrench having device for indication of wrench size and turning orientation

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates generally to a hand tool, and more particularly to a ratchet wrench, which the size of the wrench and the turning orientation are easy to identify.  
      2. Description of the Related Art  
      A conventional ratchet wrench has a color of silver and is labeled with wrench size thereon. The ratchet wrench has a handle. A ratchet wheel and a pawl are mounted at an end of the handle. The pawl restricts the ratchet wheel for only rotation along one orientation. If a bolt or a nut needs to be loosed, the ratchet wheel is engaged with the bolt (or nut) and exerts the handle for rotation counterclockwise. Under such condition, the handle can be turned reversibly and leave the bolt keeping still, such that the wrench can turn the bolt loose repeatedly. If the ratchet wrench is engaged with the bolt via the other side thereof, the ratchet wrench can turn a bolt or a nut tight repeatedly.  
      The conventional ratchet wrench lacks of any sign indicating which orientation is to tight and which orientation is to loose. User needs try and error every time when turning a nut or a bolt. Sometime user may hit the target for the first time, but sometime needs two times of try. The problem of confusing with the turning orientations of the conventional ratchet wrench is occurred both on old hands and new hands.  
      The ratchet wrenches have metric system and British system in the present market. If the user has both metric wrenches and British wrenches and put them in the same place, he/she might confuse which one is metric wrench and which one is British wrench when the sizes of the wrenches are close. User has to read the sign on the wrench to identify the exact size thereof and that makes user inconvenient.  
     SUMMARY OF THE INVENTION  
      The primary objective of the present invention is to provide a ratchet wrench, which is easy to be identified which one is metric wrench and which one is British wrench.  
      The secondary objective of the present invention is to provide a ratchet wrench, which is easy to be identified which orientation is to loose a bolt/nut and which orientation is to tight a bolt/nut.  
      According to the objectives of the present invention, a ratchet wrench comprises a wrench body having a hole at an end thereof and a chamber communicated with the hole. A ratchet wheel has an annular teeth portion at an outer surface thereof. The ratchet wheel is rotatably mounted in the hole of the wrench body. A pawl for meshing the teeth portion of the ratchet wheel and a spring having an end stopped at the pawl are mounted in the chamber of the wrench body. A ring member is mounted in the hole of the wrench body and has a predetermined color that is different from a color of the wrench body and visible from outside of the ratchet wrench for indicating the turning orientation of loosing and/or tightening.  
      Preferably, an identification layer having a color different from the wrench body is disposed on a ring member instead of the above-mentioned colored ring member.  
      Preferably, the ring member is integrally formed at an end of the ratchet wheel. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is an exploded view of a first preferred embodiment of the present invention;  
       FIG. 2  is a perspective view of the first preferred embodiment of the present invention;  
       FIG. 3  is a sectional view along line  3 - 3  of  FIG. 1 ;  
       FIG. 4  is a sectional view of the ring member of the first preferred embodiment of the present invention;  
       FIG. 5  is a sectional view of a second preferred embodiment of the present invention;  
       FIG. 6  is a sectional view of the ring member of the second preferred embodiment of the present invention, and  
       FIG. 7  is a sectional view of the ring member of a third preferred embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      As shown in  FIG. 1  and  FIG. 2 , a ratchet wrench  10  of the first preferred embodiment of the present invention comprises elements as follows.  
      An elongated wrench body  20  has a hole  21  at an end thereof, a chamber  22  communicated with the hole  21 , a recess  23  on a sidewall of the chamber  22  and an annular slot  25  on a sidewall of the hole  21 . The wrench body  20  is provided with a sign  24  indicating the size of the wrench.  
      A ratchet wheel  30  is mounted in the hole  21  of the wrench body  20  for free rotation. The ratchet wheel  30  has a teeth portion  31  on an outer surface thereof and a polygonal hole  32  at a center thereof.  
      A ring member  40  has a color different from the color of the wrench body  20 . The ring member  40  has an annular slot  41  at middle of an outer surface thereof. The ring member  40  is mounted in the holes  21  of the wrench body  20  between the ratchet wheel  30  and the sidewall of the hole  21 . A C-ring  50  is received in both of the annular slots  25  and  41  of the wrench body  20  and the ring member  40  to restrain the ratchet wheel  30  in the hole  21  but still leaves the ratchet wheel  30  for free rotation.  
      A pawl  60  is received in the chamber  22  of the wrench body  20  for meshing the teeth portion  31  of the ratchet wheel  30 .  
      A spring  70  has a portion thereof received in the recess  23  and has a distal end thereof against the pawl  60  to provide the pawl  60  a spring force.  
      The ratchet wrench  10  of the present invention provides the ring member  40  having the color different from the color of the wrench body  20 . It makes the user easy to identify which one is the metric wrench and which one is the British wrench. For example, we provide the metric wrenches having blue ring member and the British wrenches having red ring member, such that user can identify these wrenches simply by viewing the color of the ring member  40  thereon.  
      The ring member  40  has an additional indication of turning orientation. For example, if a user wants to loose the bolt, the ratchet wrench  10  of the present invention is fitted to the bolt with the colored ring member  40  facing outward which is visible for the user. On the other hand, if a user wants to tight the bolt, the ratchet wrench  10  is fitted to the bolt with the colored ring member  40  facing inward which is invisible for the user. So that the user is easy to identify the turning orientation of the ratchet wrench  10  of the present invention via the ring member  40 .  
      The C-ring  50  is hidden in the annular slots  25  and  41  of the wrench body  20  and the ring member  40 . It is invisible from outside so that the C-ring  50  will not affect the indication of the ring member  40 .  
       FIG. 5  shows a ratchet wrench  80  of the second preferred embodiment of the present invention, which is similar to the first preferred embodiment, having a wrench body  81 , a ratchet wheel  82  and a ring member  83 . The ring member  83  is coated with an identification layer  84  as shown in  FIG. 6 . The identification layer  84  has a predetermined color and is made by printing, plating, painting or the other similar ways. The color of the identification layer  84  is different from the color of the wrench body  81  to serve the functions as described above.  
       FIG. 7  shows a ratchet wrench  90  of the third preferred embodiment of the present invention. A ring member  93  is integrally formed at an end of a ratchet wheel  91 . The ratchet wheel  91  has an annular slot  93  at an outer surface of the other end. A C-ring  94  is mounted in the annular slot  93  to restrain the ratchet wheel  91  in a wrench body  95 . The feature of the third preferred embodiment is characterized in that the ratchet wheel  91  and the ring member  93  are molded in a single element. An identification layer  96 , which is an annular film, is attached on the ring member  93 . The identification layer  96  has a color different from the color of the wrench body  95  to serve the functions as described above.  
      The main scope of the present invention is to provide a ring member having a color different from the color of the wrench body for indication of the wrench&#39;s size and the turning orientation.