Patent Abstract:
A wrench with a quick release handle for providing torque to a fastener. The wrench comprises a wrench head having a retention opening for engaging the fastener and at least two engagement portions for attachment of a releasable handle thereat. The retention opening includes and open end for allowing the wrench head to be laterally extensible over the fastener. The engagement portion of the wrench head includes a head channel that can receive a corresponding handle lip disposed on the handle in order facilitate engagement between the wrench head and the handle. Additionally, the handle further includes a locking mechanism for maintaining releasable attachment between the wrench head and the handle.

Full Description:
FIELD OF THE INVENTION 
     The present invention generally relates to wrenches and more specifically to a wrench head with a detachable handle that can be used for engaging hex heads in confined spaces. 
     BACKGROUND OF THE INVENTION 
     Currently, conventional open end wrenches are ideal for engaging a nut or bolt head (e.g., hex head) wherein a socket cannot be engaged thereover because access to the hex head is limited. However, a drawback to such open end wrenches is that the handle is attached to the wrench head thereby making engagement with the hex head difficult. As such, the conventional open end wrench is difficult to use when the hex head to be tightened or released is in a confined space. Specifically, the wrench will have to be removed from the hex head when the handle cannot be moved due to the limited area in which to swing the handle. Therefore, tightening or releasing a hex head can be a tedious process with a conventional open end wrench because the wrench will need to be removed from the hex head and then re-engaged in order to provide torque to the hex head. Additionally as previously discussed, it can be difficult to engage the hex head with a conventional open end wrench because the opening of the wrench must be rotationally aligned with the hex head for proper engagement. Therefore, removing an open end wrench from the hex head during torquing is not advantageous because it is difficult to rotationally re-align the wrench with the hex head. 
     The present invention addresses the deficiencies of prior art open end wrenches by providing a wrench that comprises a handle detachable from a wrench head. The wrench head includes a plurality of engagement positions for the handle such that the wrench head does not need to be removed from the nut during torquing. The handle can be removed from the wrench head and easily engaged to any one of a plurality of engagement positions in order to torque a hex head in a confined space. Additionally, the wrench head of the present wrench is easily engagable to the hex head due to its compact size and detachable handle. 
     SUMMARY OF THE INVENTION 
     In accordance with the preferred embodiment of the present invention there is provided a wrench for use with a fastener. The wrench comprises a wrench head having a retention opening for engaging the fastener and at least two engagement portions. Furthermore the wrench comprises an elongate handle releasably attachable to the wrench head at any one of the engagement portions. The wrench head may comprise three engagement portions equidistantly spaced at intervals of about 50 degrees to 55 degrees. 
     The wrench constructed in accordance with the preferred embodiment may further include an open end at the retention opening for allowing the wrench head to be laterally extensible over the fastener. Additionally, the retention opening may define four sides which corresponding to the sides of the fastener which may be a six-sided hex head. 
     In accordance with the preferred embodiment of the present invention, the engagement portion of the wrench head may include a recessed head channel. As such, the handle will further include a handle lip which is receivable into the channel of the engagement portion to facilitate releasable attachment of the handle to the wrench head. Furthermore, the handle may include a handle channel and each of the engagement portions may include head lip which is receivable into the handle channel to facilitate releasible attachment of the wrench head to the handle. In order to assist in maintaining the handle in releasable attachment to the wrench head, the handle may further comprises a locking mechanism. The locking mechanism includes a biasing spring disposed within the channel and a friction member disposed on one end of the biasing spring and normally biased against the head lip of one of the engagement portions. 
     The present invention further comprises a method of providing torque to a fastener with a wrench. The wrench includes a wrench head having a retention opening for engaging the fastener and at least two engagement portions, and a handle which is attachable to the wrench head at any one of the engagement positions thereof. The method comprises the steps of placing the fastener within the retention opening, attaching the handle to one of the engagement portions, and then rotating the handle to provide torque to the fastener. If the swing range of the handle is limited, then the handle is released from the wrench head and attached to a another one of the engagement portions of the wrench head in order to further rotate the handle. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These, as well as other features of the present invention, will become more apparent upon reference to the drawings wherein: 
     FIG. 1 is a top perspective view of the wrench constructed in accordance with the preferred embodiment of the present invention as used with a hex head fastener; 
     FIG. 2 is a bottom perspective view of the wrench shown in FIG. 1; 
     FIG. 3 is a bottom perspective view of the wrench shown in FIG. 1 with the handle detached from the wrench head; 
     FIG. 4 is a top perspective view of the wrench head for the wrench of the present invention; 
     FIG. 5 is a bottom cut-away perspective view of the wrench head shown in FIG. 2; and 
     FIG. 6 is a partial cross-sectional view taken along line  6 — 6  of FIG.  3 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings wherein the showings are for purposes of illustrating a preferred embodiment of the present invention only, and not for purposes of limiting the same, FIG. 1 perspectively illustrates a wrench  10  constructed in accordance with the preferred embodiment of the present invention. The wrench  10  comprises a metallic wrench head  12  and a metallic, detachable handle  14 . The wrench  10  is used for providing torque to a six-sided hex head fastener such as a nut  16  or the head of a bolt (not shown). As seen in FIG. 1, the wrench head  12  partially bounds the outside circumference of the nut  16  with a hex head retention opening  18  similar to a conventional open ended wrench. As such, the wrench head  12  can be sized to be laterally extensible over standard, metric, and english sized hex head fasteners. 
     The hex head retention opening  18  frictionally engages the nut  16  during torquing. As seen in FIGS. 4 and 5, the retention opening  18  comprises four end-to-end walls  26  sized and configured to be slightly larger than four corresponding faces of the nut  16  to be tightened or loosened. As such, the wrench head  12  will remain in frictional engagement on the nut  16  during removal of the handle  14  as will be explained in greater detail below. Additionally, the retention opening  18  may be provided with tubular grooves  19  between each pair of walls  26  for preventing the corners of the nut  16  from being worn during rotation of the wrench head  12 . 
     The wrench  10  is designed to be used in situations where the swing range of the handle  14  is limited due to an obstruction such as often occurs when working on an engine of an automobile. When the swing range of the handle  14  is limited, it is desirable to tighten or loosen the nut  16  without having to remove the wrench head  12  from nut  16  in order to avoid alignment difficulties. Therefore, the handle  14  is detachable from wrench head  12  and can be placed at any one of three separate engagement portions  20  of the wrench head  12 . As best seen in FIG. 4, the wrench head  12  comprises three engagement portions  20  that are each operative to releasably couple handle  14  to wrench head  12  for torquing. Therefore, in order to use the wrench  10  in situations where the swing range of handle  14  is limited, the wrench head  12  is placed over the nut  16  in a position whereby handle  14  engages any one of the engagement portions  20 . Then the handle  14  is turned to apply torque to the nut  16  via the wrench head  12 . When the swing range of handle  14  is limited, it is disengaged from wrench head  12  and re-engaged at a different engagement portion  20  to allow the handle  14  to be swung. As such, the geometry of the wrench head  12  allows the handle  14  to be swung further than a conventional open ended wrench thereby reducing the need to remove the wrench head  12  from the nut  16 . 
     As can be seen in FIG. 4, the engagement portions  20  are positioned partially around the outside surface of the wrench head  12  in equidistantly spaced intervals of about 50 to 55 degrees. Therefore, as the wrench head  12  is rotated, the handle is engagable to an engagement portion  20  that will allow the handle to swing in order to provide torque. However, when the wrench head  12  has been rotated to a position wherein the handle cannot engage any engagement portion  20 , then the wrench head  12  must be removed from the nut  16  and rotated to engage the nut  16  at a position whereby the handle  14  can couple with one of the engagement portions  20  and still be able to swing to provide torque thereto. As previously mentioned, the geometry of the spacing between the portions  20  mitigates the need to remove the wrench head  12  from the nut  16 . As will be recognized, the number and spacing of the engagement portions  20  may vary depending upon the size of handle  14  and wrench head  12 . 
     As seen in FIG. 5, a cross-sectional view of the wrench head  12 , each engagement portion  20  comprises a wrench head channel  22  and a wrench head lip  24 . The wrench head channel  22  and lip  24  are sized and configured such that they can engage a complementary structure on the handle  14  as will be described in greater detail below. The wrench head channel  22  is a generally rectangularly shaped recess and the wrench head lip  24  is disposed adjacent thereto. The wrench head lip  24  is also generally rectangular and has substantially the same dimensions as the channel  22 . However, the lip  24  projects upward from the base of the channel  22  a distance that allows the handle  14  to engage the wrench head  12  as seen FIG.  1 . It will be recognized by those of ordinary skill in the art, that each engagement portion  20  does not necessarily need to be rectangular, but can be any shape or size that will facilitate the engagement and easy removal of handle  14  from wrench head  12 . 
     In the preferred embodiment of the present invention, the elongate handle  14  is formed to engage the wrench head  12  at any engagement portion  20 . Therefore, as seen in FIG. 6, the head  28  of handle  14  is formed with a handle channel  30  and a handle lip  32 . The handle lip  32  is sized and configured to be receivable into the wrench head channel  22  of the engagement portion  20 . Additionally, it is contemplated that the wrench head lip  24  is sized and configured complementary to the handle channel  30  such that wrench head lip  24  is receivable into handle channel  30 . Therefore, as seen in FIG. 1, the handle  14  is engaged to the wrench head  12  when wrench head lip  24  is received into the handle channel  30  concurrently with the receipt of handle lip  32  into wrench head channel  22 . 
     The coupling of the wrench head  12  to handle  14  is assisted by a locking mechanism  34  that engages a complementary recess  52  formed on a side of wrench head  12  opposite to engagement portion  20 . The locking mechanism  34  comprises a trigger  40  that is slidably attached to the handle  14  within a slot  36 . The trigger  40  has a locking tab  44  that protrudes over the handle channel  30  when the trigger  40  is in a locked position, as seen in FIG.  6 . When the trigger  40  is in an unlocked position, the locking tab  44  does not extend over the handle channel  30 . The locking tab  44  is sized slightly smaller than the recess  52  such that when the trigger  40  is in the locked position and the handle  14  is engaged to the wrench head  12 , the locking tab  44  is disposed within the recess  52 . The trigger  40  further includes a finger slide portion  46  that is easily gripped by a finger of the user to slide the trigger  40  between the locked and unlocked positions. The trigger  40  is normally biased in the locked position by a spring  38  disposed within the slot  36 . A retention pin  48  secures the trigger within the slot  36 . As seen in FIG. 2, the retention pin  48  is inserted into a bore  50  formed within the handle  14 . The trigger  40  is formed with a retention pin channel  51  having a longitudinal axis that is generally perpendicular to the axis of the retention pin  48 . The retention pin channel  51  is an elongate oval such that the trigger  40  is slidable upon the retention pin  48 , yet the trigger  40  and spring  38  are maintained within the slot  36 . When the handle  14  and the wrench head  12  are engaged, the locking tab  44  is disposed within a respective recess  52  of the wrench head  12  thereby preventing the wrench head  12  from being removed from the handle  14 . In order to remove the wrench head  12 , the trigger  40  is slidably moved away from the wrench head  12  thereby removing the locking tab  44  from a respective recess  52 . In order to attach the wrench head  12  to the handle  14 , the trigger  40  must be slid away from the handle channel  30  in order to for handle lip  32  to fully engage wrench head channel  22 . 
     Additional modifications and improvements of the present invention may also be apparent to those of ordinary skill in the art such as configuring the wrench head  12  to engage different types and shapes of fasteners. Thus, the particular combination of parts described and illustrated herein is intended to represent only a certain embodiment of the present invention, and is not intended to serve as a limitation of alternative devices within the spirit and scope of the invention.

Technology Classification (CPC): 1