Patent Publication Number: US-2007107561-A1

Title: Wrench assembly

Description:
PRIORITY CLAIM  
      This application claims priority to U.S. Provisional Application Ser. No. 60/730,540 filed on Nov. 14, 2005, the entire disclosure of which is hereby incorporated by reference. 
    
    
     TECHNICAL FIELD  
      The present invention relates to wrenches and particularly to a device that prevents jaw spread of open end wrenches.  
     BACKGROUND  
      An open end wrench is a wrench that has an open ended head used to rotate various fasteners, such as nuts and bolts. Examples of open end wrenches include but are not limited to, double open end wrenches, combination wrenches, and flare nut wrenches. An open end wrench can access fasteners under certain limited-access conditions where a closed end wrench (also known as a box wrench) cannot. For example, a closed end wrench cannot access a nut on a brake line or air conditioning line without cutting the line.  
      Although open end wrenches provide better access to fasteners than closed end wrenches, open end wrenches typically cannot apply as much torque to fasteners as closed end wrenches. This is due to flexing of the wrenches&#39; jaws, also known as jaw spread, when the wrench is under torque. This weakness of open end wrenches reduces torque capacity and promotes fastener deformation and wrench wear.  
      There have been attempts to increase the strength and torque capacity of open end wrenches. For example, serrations have been formed on the jaws&#39; engaging surfaces to increase grip, but this leaves bite or shred marks on the fastener. Attempts have also been made to increase torque capacity using inclined and arcuate driving surfaces.  
     SUMMARY  
      According to one aspect, the present invention provides a wrench assembly with an open-end wrench and a support member adapted to prevent jaw spread of the wrench. In some embodiments, the wrench has an open-end head portion with spaced apart jaws. The support member is releasably coupled to the open-end head portion of the wrench and prevents relative movement of the jaws when the wrench applies torque to a fastener. In some cases, the support member includes portions adjacent exterior surfaces of the jaws. Embodiments are contemplated in which the support member extends between the jaws. Depending on the particular circumstances, the wrench&#39;s jaws may includes notches (or other openings) that receive portions of the support member. In some cases, the support member is co-planar with respect to the wrench&#39;s head portion; in other embodiments, the support member may be approximately perpendicular to the wrench. In some embodiments, the wrench&#39;s jaws are fixed with respect to each other. The support member may be configured to enclose the head portion of the wrench, in some embodiments.  
      According to further aspect, the present invention provides a support member for use with an open end wrench. The support member has a body adapted to be releasably coupled to the wrench. The body includes portions configured to limit flexing of the wrench&#39;s jaws. Another portion of the support member extends between the wrench&#39;s jaws. In some embodiments, the support member may be made of aluminum or steel. Embodiments are contemplated in which the support member may be a single piece unitary member. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
      The present disclosure will be described hereafter with reference to the attached drawings which are given as non-limiting examples only, in which:  
       FIG. 1  is a perspective view of a wrench assembly according to a first embodiment of the invention;  
       FIG. 2  is an exploded perspective view of the wrench assembly shown in  FIG. 1 ;  
       FIG. 3  is a side exploded view of the wrench assembly shown in  FIG. 1 ;  
       FIG. 4  is an exploded perspective view of a wrench assembly according to a second embodiment of the invention;  
       FIG. 5  is an exploded perspective view of a wrench assembly according to a third embodiment of the invention;  
       FIG. 6  is a side exploded view of a wrench assembly according to a fourth embodiment of the invention; and  
       FIG. 7  is a perspective view of a wrench assembly according to a fifth embodiment of the invention. 
    
    
      Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates example embodiments of the invention, and such exemplification is not to be construed as limiting the scope of the invention in any manner.  
     DETAILED DESCRIPTION OF THE DRAWINGS  
      It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only, and is not intended as limiting the broader aspects of the present invention, which broader aspects are embodied in the exemplary constructions.  
       FIGS. 1-3  show a wrench assembly  100  according to an embodiment of the present invention. In the example shown, the wrench assembly  100  includes a wrench  102  and a support member  104 . The support member  104  limits jaw spread when the wrench  102  is under torque.  
      The wrench  102  is preferably an open end wrench, such as a single open end wrench, double open end wrench, combination wrench, or flare nut wrench. As shown, the wrench  102  includes a grip portion  106 , and an open end head portion  108 . Although the head portion  108  is coplanar with the grip portion  106  in the example shown, embodiments are contemplated in which the head portion  108  may be angled with respect to the grip portion  106 . By way of another example, the head portion  108  may be pivotally connected to the grip portion  106 .  
      As shown, the head portion  108  includes a first jaw  110  and a second jaw  112 . The jaws  110 ,  112  are preferably spaced apart to receive a fastener  114 , such as a nut, through a receiving end  116 . Although the jaws  110 ,  112 , are fixed in the example shown, embodiments are contemplated in which the jaws  110 ,  112  may be adjustable to receive various sizes of fasteners. The jaws  110 ,  112  include an interior surface  118  configured to engage the fastener and an exterior surface  120 . In the embodiment shown, the first jaw  110  includes a notch  122  and second jaw  112  includes a notch  124 . Notches  122 ,  124  are configured to receive portions of the support member  104 .  
      In some embodiments, the support member  104  may be releasably coupled to the wrench  102 . Alternatively, a portion of the support member  104  could be permanently coupled to the wrench  104 . For example, the support member  104  could be pivotally coupled to the wrench  104 . The terms “couple” and “coupled” are intended broadly to encompass both direct and indirect coupling. Thus, the support member  104  and the wrench  102  are said to be coupled together when they are directly connected (e.g., by direct contact, such as an interference fit or frictional fit, of the support member  104  with the wrench  102 ), as well as when the support member  104  and the wrench  102  are indirectly coupled (e.g., by a hinge pivotally connecting the support member  104  to the wrench  102  or a magnetic attraction between the support member  104  and the wrench  102 ).  
      In the example shown, the support member  104  includes a first extension  126  and a second extension  128 . The extensions  126 ,  128  are spaced apart a suitable distance to be received by the notches  122 ,  124 . Preferably, the extensions  126 ,  128  frictionally engage the exterior surface  120  of the jaws  110 ,  112  in the notches  122 ,  124  in this embodiment, which reduces lateral movement. The support member  104  rigidly supports the jaws  110 ,  112  to prevent flexing of the jaws  110 ,  112  when the wrench  102  applies torque to a fastener  114 . By way of example only, the support member  104  may be formed from steel or cast aluminum in some embodiments. In some cases, the support member  104  may be formed from a rigid material that is coated with plastic or rubber. Although the support member  104  is a single-piece unitary member in the example shown, embodiments are contemplated in which the support member  104  could be manufactured in multiple portions that are assembled together to form the support member  104 . For example, a first portion with first extension  126  could be movable with respect to a second portion with the second extension  128  to accommodate various sizes of wrenches.  
       FIG. 4  shows a wrench assembly  400  according to another embodiment. In this embodiment, the wrench assembly  400  includes a support member  402  with an arcuate portion  404 . A first extension  406  and a second extension  408  extend from the arcuate portion  404  to be received in notches  410 ,  412  of the wrench  414 . In this embodiment and the embodiment shown in  FIGS. 1-3 , the support member  104 ,  402  is approximately coplanar with the head portion  108  of the wrench  102 ,  414 .  
       FIG. 5  shows a wrench assembly  500  according to another embodiment. In this embodiment, the wrench assembly  500  includes a support member  502  with a first extension  504  and a second extension  506  that are received in the notches  508 ,  510  of a wrench  512 . In this embodiment, the extensions  504 ,  506  are approximately perpendicular to a longitudinal axis of the wrench  512 .  
       FIG. 6  shows a wrench assembly  600  according to another embodiment. In this embodiment, the wrench  602  does not include any notches to receive the support member  604 . Instead, the support member  604  is configured to tightly surround the exterior surface of the wrench  602 . In some embodiments, the support member  604  may include one or more extensions  606  that prevent lateral movement of the support member  604  with respect to the wrench  602 .  
       FIG. 7  shows a wrench assembly  700  according to another embodiment. In this embodiment, the support member  702  includes extensions  704 ,  706  that extend transversely from a base portion  708 . In this example, the extensions  704 ,  706  are received within notches  710 ,  712  of a wrench  714 . In some cases, the support member  702  may be a chain drive master link.  
      In use, a fastener  114  may be received through the receiving end  116  of the wrench  102 . The support member  104  (or  402 ,  502 ,  602 , or  702  in other embodiments) may then be coupled to the head portion  108  of the wrench  102 . When the wrench  102  applies torque to the fastener  114 , the support member  104  prevents flexing of the wrench&#39;s  102  jaws  110 ,  112 . Accordingly, the torque capacity of the wrench  102  is increased.  
      Although the present disclosure has been described with reference to particular means, materials and embodiments, from the foregoing description, one skilled in the art can easily ascertain the essential characteristics of the present disclosure and various changes and modifications may be made to adapt the various uses and characteristics without departing from the spirit and scope of the present invention as set forth in the following claims.