Patent Publication Number: US-6708586-B1

Title: Ratchet wrench having a direction controller that is assembled easily

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a ratchet wrench having a direction controller that is assembled easily, and more particularly to a ratchet wrench having a direction controller that may be directly mounted on the drive head, so that the ratchet wrench has a simplified construction and may be assembled and disassembled easily and conveniently. 
     2. Description of the Related Art 
     conventional ratchet wrench in accordance with the prior art comprises a wrench body having a drive head, a ratchet wheel rotatably mounted on the drive head, a direction controller pivotally mounted on the drive head, and a pawl member mounted between the direction controller and the ratchet wheel. Thus, the direction controller may drive the pawl member to control the rotational direction of the ratchet wheel. However, the direction controller is mounted on the drive head by a complicated mounting structure, so that the ratchet wrench has a complicated construction and cannot be assembled and disassembled easily and conveniently, thereby increasing the cost of fabrication. 
     SUMMARY OF THE INVENTION 
     The present invention has arisen to mitigate and/or obviate the disadvantage of the conventional ratchet wrench. 
     The primary objective of the present invention is to provide a ratchet wrench having a direction controller that is assembled easily. 
     Another objective of the present invention is to provide a ratchet wrench having a direction controller that is assembled easily, wherein the direction controller may be directly mounted on the drive head, so that the ratchet wrench has a simplified construction and may be assembled and disassembled easily and conveniently. 
     In accordance with the present invention, there is provided a ratchet wrench having a direction controller that is assembled easily, comprising a drive head, a ratchet wheel rotatably mounted on a bottom face of the drive head, a direction controller pivotally mounted on a top face of the drive head, and a pawl member mounted between the direction controller and the ratchet wheel; 
     the drive head has a bottom face formed with a receiving chamber for receiving the ratchet wheel and the pawl member, the receiving chamber has a wall having a closed upper portion formed with a shaft recess, the drive head has a top face formed with a pivot hole communicating with the receiving chamber, the ratchet wheel has a top portion provided with a shaft rotatably mounted in the shaft recess of the drive head; wherein: 
     the wall of the receiving chamber is formed with an expansion slot communicating with the shaft recess and the pivot hole, the direction controller has a periphery formed with a slit facing the expansion slot of the drive head, and the ratchet wrench further comprises an insertion plate mounted in the expansion slot of the drive head, the insertion plate has a first side provided with a flat cut edge that may be inserted into the slit of the direction controller, and a second side provided with an arcuate edge that is rested on an outer edge of the shaft of the ratchet wheel. 
    
    
     Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded perspective view of a ratchet wrench having a direction controller that is assembled easily in accordance with a preferred embodiment of the present invention; 
     FIG. 2 is a side plan cross-sectional assembly view of the ratchet wrench having a direction controller that is assembled easily as shown in FIG. 1; and 
     FIG. 3 is a top plan cross-sectional assembly view of the ratchet wrench having a direction controller that is assembled easily as shown in FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings and initially to FIG. 1, a ratchet wrench having a direction controller that is assembled easily in accordance with a preferred embodiment of the present invention comprises a wrench body having a drive head  10 , a ratchet wheel  30  rotatably mounted on a bottom face of the drive head  10 , a direction controller  20  pivotally mounted on a top face of the drive head  10 , and a pawl member  25  mounted between the direction controller  20  and the ratchet wheel  30 . Thus, the direction controller  20  may drive the pawl member  25  to control the rotational direction of the ratchet wheel  30 . 
     Referring to FIGS. 1-3, the drive head  10  has a bottom face formed with a receiving chamber  11  for receiving the ratchet wheel  30  and the pawl member  25 . The receiving chamber  11  has a wall having a closed upper portion formed with a shaft recess  12  for receiving a top portion of the ratchet wheel  30 , and an opened lower portion provided with a stepped edge  13  for limiting the ratchet wheel  30 . The drive head  10  has a top face formed with a pivot hole  15  communicating with the receiving chamber  11  for receiving the direction controller  20 . The pivot hole  15  has a wall formed with a receiving space  150  for receiving an elastic positioning stub  16  which is urged on a periphery of the direction controller  20  for positioning the direction controller  20 . The wall of the receiving chamber  11  is formed with an expansion slot  17  communicating with the shaft recess  12  and the pivot hole  15 . 
     The direction controller  20  pivotally mounted in the pivot hole,  15  of the drive head  10  has a first side formed with a concave positioning edge  21  rested on the elastic positioning stub  16 , and a second side formed with an insertion hole  22  for insertion of an elastic member  23  which is urged on a periphery of the pawl member  25 . The direction controller  20  has a periphery formed with a slit  24  facing the expansion slot  17  of the drive head  10 . Preferably, the slit  24  is integrally formed in the direction controller  20 . The pawl member  25  has a first side formed with a limit recess  26  for retaining the elastic member  23  of the direction controller  20 , and a second side engaged with a periphery of the ratchet wheel  30 . 
     The ratchet wheel  30  has a top portion provided with a shaft  31  rotatably mounted in the shaft recess  12  of the drive head  10 , and a bottom portion provided with a stepped edge  32  for limiting movement of the ratchet wheel  30 . The stepped edge  32  of the ratchet wheel  30  has a bottom provided with a downward protruding socket stud  35  which is provided with a retaining ball  36 . 
     The ratchet wrench in accordance with the present invention further comprises a sheet-shaped insertion plate  40  mounted in the expansion slot  17  of the drive head  10 . The insertion plate  40  has a first side provided with a flat cut edge  41  that may be inserted into the slit  24  of the direction controller  20  (see FIG.  3 ), and a second side provided with an arcuate edge  42  that is rested on an outer edge of the shaft  31  of the ratchet wheel  30 . The pawl member  25  is urged on a bottom of the insertion plate  40 , so that the direction controller  20  may be retained on the drive head  10 . 
     In assembly, the direction controller  20  is pivotally mounted in the pivot hole  15  of the drive head  10 , with the slit  24  of the direction controller  20  aligning with the expansion slot  17  of the drive head  10 . Then, the insertion plate  40  is mounted in the expansion slot  17  of the drive head  10 , and the flat cut edge  41  of the insertion plate  40  is inserted into the slit  24  of the direction controller  20  for locking the direction controller  20 . Then, the ratchet wheel  30  is rotatably mounted in the receiving chamber  11  of the drive head  10 , with the arcuate edge  42  of the insertion plate  40  being rested on the outer edge of the shaft  31  of the ratchet wheel  30 . Then, the pawl member  25  is pivotally mounted in the receiving chamber  11  of the drive head  10 , and is urged on the bottom of the insertion plate  40 , so that the direction controller  20  may be retained on the drive head  10 . Finally, a bottom cap  18  is mounted in the receiving chamber  11  of the drive head  10 , and is rested on the stepped edge  13  of the drive head  10  and the stepped edge  32  of the ratchet wheel  30 , thereby assembling the ratchet wrench in accordance with the present invention. 
     In such a manner, the insertion plate  40  may be used to retain the direction controller  20  on the drive head  10 . 
     Accordingly, the ratchet wrench in accordance with the present invention has a simplified construction, and may be assembled and disassembled easily and conveniently, thereby decreasing the cost of fabrication. 
     Although the invention has been explained in relation to its preferred embodiment as mentioned above, it is to be understood that many other possible modifications and variations can be made without departing from the scope of the present invention. It is, therefore, contemplated that the appended claim or claims will cover such modifications and variations that fall within the true scope of the invention.