Patent Publication Number: US-6655239-B1

Title: Double-ended wrench with ergonomic handle

Description:
FIELD OF THE INVENTION 
     The present invention relates to hand tools, particularly hand operated double-ended wrenches including combination wrenches, box wrenches, open end wrenches, flex head wrenches and the like. 
     BACKGROUND OF THE INVENTION 
     Hand operated double-ended wrenches have been around for many years and they are typically structured having an elongated, flat shaped handle with a wrench head at each end for turning various fasteners. Typical variations include combination, double box, double open-end, flex-head type and the like. The flat shaped handle connected to each wrench head provides each wrench head with excellent accessibility to fasteners. It is, however, the flat shaped handle that creates a major disadvantage associated with this tool. The elongated, flat handle provides only a thin surface area for the application of force by a user to turn and operate the wrench. This minimal surface area creates user discomfort and fatigue, while limiting torque and continuous-use capabilities. 
     More recently, there have been attempts to improve the double-ended wrench by simply distorting or twisting the handle of the older prior art wrench. This twisted handle configuration does provide some advantages including a greater surface area for the application of force by a user at each end of the wrench. However, the distorted or twisted handle also creates new problems including a reduction in strength and torque capacity, and a reduction in accessibility to fasteners under some conditions. In addition, the distorted shape of the wrench handle may feel awkward and appear damaged or bent to a user. 
     Accordingly, there is a significant need to improve upon the typical prior art, double-ended wrenches. The improvements contemplated would provide a user with less fatigue, improved comfort and torque capabilities. While contemplating such improvements, however, it is important not to sacrifice the inherent good features of the wrench which include its two wrench heads and excellent accessibility to fasteners. 
     SUMMARY OF THE INVENTION 
     The present invention involves a double-ended wrench comprising an elongated handle formed substantially nontwisted extending in a longitudinal direction, a first wrench head positioned at one end of the wrench and a second wrench head positioned at the other end thereof. Each wrench head has an orifice with an imaginary axis of wrench rotation. The first wrench head is positioned relative to the second wrench head whereas the axis of wrench rotation of the first wrench head is substantially perpendicular to the axis of wrench rotation of the second wrench head. The elongated handle comprises a first handle portion connecting to the first wrench head, and a second handle portion connecting to the second wrench head. Each handle portion has an elongated cross-sectional shape when viewed in a cross-sectional plane perpendicular to the longitudinal direction. Each cross-sectional shape is elongated in a predetermined direction, and, the first handle portion is positioned relative to the second handle portion whereas the cross-sectional shape of the first handle portion is elongated in a direction substantially perpendicular to the direction in which the cross-sectional shape of the second handle portion is elongated. 
     Applicant recognizes the need for an improved double-ended wrench, one which provides a user with less fatigue, improved comfort and torque capabilities. While contemplating such improvements, applicant further recognizes the importance of not sacrificing the inherent good features of the typical double-ended wrench which include its two wrench heads and excellent accessibility to fasteners. 
     Accordingly, it is an important objective of the present invention described above, that it have two wrench heads. 
     It is another important objective of the present invention described above, that it be structured for excellent accessibility to fasteners. 
     It is another important objective of the present invention described above, that it be structured to reduce fatigue, improve comfort and torque capabilities. 
     It is another important objective of the present invention described above, that it be undistorted and simple in design for strength, durability and user acceptance. 
     And, it is yet another important objective of the present invention described above, that it be cost efficient to manufacture and commercially viable. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a left side, elevational view of a typical prior art double-ended wrench; and, 
     FIG. 2 shows a top plan view of the prior art wrench shown in FIG. 1; and, 
     FIG. 3 shows a left side, elevational view of a present invention double-ended wrench; and, 
     FIG. 4 shows a top plan view of the present invention wrench shown in FIG. 3; and, 
     FIG. 5 shows an end view of the present invention wrench shown in FIGS. 3 and 4; and, 
     FIG. 6 shows a cross-sectional, end view of the first handle portion of the present invention wrench shown in FIG. 3; and, 
     FIG. 7 shows a cross-sectional, end view of the second handle portion of the present invention wrench shown in FIG. 3; and, 
     FIG. 8 shows a perspective view of another present invention double-ended wrench; and, 
     FIG. 9 shows a left side, elevational view of another present invention wrench with each wrench head being pivotably connected to a wrench handle portion, and one wrench head further having a ratcheting mechanism. 
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     Referring now to the drawings which are for the purpose of illustrating preferred embodiments of the present invention and not for the purpose of limiting same, FIG. 1 shows a left side, elevational view of a typical prior art double-ended wrench. Prior art wrench  1  has an elongated wrench handle  3  and a two wrench heads  5  and  11 . Open end wrench head  5  has an imaginary central axis  7  which is the axis of wrench rotation for wrench head  5 , and, wrench head  11  has an imaginary central axis  13  which is the axis of wrench rotation for wrench head  11 . Wrench head  5  is connected to handle portion  9 , and, wrench head  11  is connected to handle portion  15 . When operating wrench  1 , a user will generally grip handle portion  15  to turn wrench head  5  about imaginary central axis  7  to turn various fasteners. Alternatively, a user will generally grip handle portion  9  to turn wrench head  11  about imaginary central axis  13  to turn various fasteners. Wrench handle portion  9  is relatively thin as seen in this side view so that wrench head  5  can easily access and engage a fastener located in common or limited-access environments. Likewise, wrench handle portion  15  is relatively thin as seen in this side view so that wrench head  13  can easily access and engage with fasteners located in common and limited-access environments. Consequently, wrench handle portion  9  provides only a minimal surface area for the application of force by a user to turn and operate wrench head  11 , and, handle portion  15  provides only a minimal surface area for the application of force by a user to turn and operate wrench head  5 . This minimal surface area promotes user discomfort and fatigue, while limiting torque and continuous-use capabilities. 
     FIG. 2 shows a top plan view of the prior art wrench shown in FIG. 1 with all visible components having the same reference numbers. 
     Referring now to both FIGS. 1 and 2 together, if wrench  1  were to be viewed from an end view (not shown), it is easy to comprehend that the imaginary central axis  7  of wrench head  5  would be substantially parallel to the imaginary central axis  13  of wrench head  11 . And, if wrench  1  were to be viewed from an end view thereof, it is easy to comprehend that first handle portion  9  and second handle portion  15  would each have an elongated cross-sectional shape, with the elongation of each handle portion shape positioned substantially parallel and aligned to the other. And, the side surface of handle  3  (including handle portions  9  and  15 ) shown in FIG. 1, is not tapered at all or in either direction, but is formed with substantially parallel sides as shown. And, the top surface of handle  3  (including handle portions  9  and  15 ) shown in FIG. 2, is not tapered at all in either direction, but is formed with substantially parallel sides as shown. 
     More recently, there have been attempts to improve the prior art wrench shown in FIGS. 1 and 2, by simply distorting or twisting the handle ninety degrees relative to a longitudinal axis. Structural features of such a wrench include a side handle surface which is not tapered in either direction and which does not extend in a longitudinal direction, but rather, wraps around the wrench handle in a direction other than longitudinal. Additionally, such wrench includes an upper handle surface which is not tapered in either direction and which does not extend in a longitudinal direction, but rather, wraps around the wrench handle in a direction other than longitudinal. It is important to understand that the side and upper surfaces of such a twisted handle are in fact, twisted, not tapered. Accordingly, a twisted wrench handle does not have a side or upper “surface” which is substantially “continuous” as defined herein, nor does it have a side or upper “surface” which is “common” to both ends of the wrench handle, as defined herein. Such a “distorted” wrench as defined herein, creates new problems including a reduction in strength and torque capacity, and a reduction in accessibility to fasteners under some conditions. In addition, a distorted wrench handle may feel awkward and appear damaged or bent to a user. A “tapering” wrench surface shall be defined herein as a wrench surface that decreases in width or thickness. 
     Accordingly, there is a significant need for an improved double-ended wrench, one which provides a user with less fatigue, improved comfort and torque capabilities, without sacrificing wrench strength or accessibility to fasteners. 
     Applicant defines a “distorted” wrench herein as being a wrench that is twisted in shape. An “undistorted” wrench, therefore, shall be defined as a wrench which is not distorted II,II or twisted in shape. A wrench “surface” shall be defined herein as the exterior of a wrench, or the exterior of a specified part of a wrench. A “continuous” wrench surface shall be defined herein as a wrench surface going on without any substantial interruption, or being unbroken. A “common” wrench surface shall be defined herein as a wrench surface which belongs to, or is shared by, two or more specified parts of the wrench. 
     Referring to FIGS. 3,  4  and  5  together, there is shown a present invention double-ended wrench shown in a left side elevational view, a top plan view, and an end view respectively. Wrench  21  is a one piece, double-ended wrench comprising a first wrench head  23  positioned at one end of an elongated handle  35  and a second wrench head  29  positioned at the other end thereof. Wrench head  23  has an orifice  24  formed for engagement with various fasteners, and wrench head  29  has an orifice  30  formed for engagement with various fasteners. Orifice  24  has an imaginary central axis of wrench rotation  25 , and orifice  30  has an imaginary central axis of wrench rotation  31 . First wrench head  23  is positioned relative to the second wrench head  29  whereas the axis of wrench rotation  25  of the first wrench head  23  is substantially perpendicular to the axis of wrench rotation  31  of the second wrench head  29  (seen best in FIG. 5.) The elongated handle  35  is formed undistorted, and comprises a first handle portion  27  connecting to the first wrench head  23 , and a second handle portion  33  connecting to the second wrench head  29 . When the wrench  21  is viewed from an end view thereof, the first and second handle portions  27  and  33  respectively, each have an elongated cross-sectional shape with the elongated cross-sectional shape of the first handle portion  27  being positioned substantially perpendicular to the axis of wrench rotation  25  of the first wrench head  23 , and substantially parallel to the axis of wrench rotation  31  of the second wrench head  29  (seen best in FIG.  6 ). And, the elongated, cross-sectional shape of the second handle portion  33  is positioned substantially perpendicular to the axis of wrench rotation  31  of the second wrench head  29 , and substantially parallel to the axis of wrench rotation  25  of the first wrench head  23  (seen best in FIG.  7 ). By positioning the handle portions to the wrench heads as shown, the wrench maintains an excellent accessibility to fasteners located in common and limited-access environments. The undistorted, elongated handle  35  further comprises a side surface  36  (seen best in FIG. 3) extending in a longitudinal direction and tapering towards the first wrench head  23  as shown. Elongated handle  35  also comprises an upper surface  37  (seen best in FIG. 4) extending in a longitudinal direction tapering towards the second wrench head  29  as shown. To operate wrench  21 , a user will generally grip handle portion  33  to turn wrench head  23  around the axis of wrench rotation  25  (seen best in FIG.  3 ), and alternatively, a user may grip handle portion  27  to turn wrench head  29  around the axis of wrench rotation  31  (seen best in FIG.  4 ). Accordingly, the side and upper surfaces of the wrench are tapered as shown to achieve a more substantial surface area for the application of force by a user to turn the wrench, while simultaneously, maintaining excellent wrench-to-fastener accessibility around the wrench head being turned. Additionally, tapered side surface  36  shown in FIG. 3 is formed being substantially continuous and common to both the first and second handle portions  27  and  33  respectively. Likewise, tapered upper surface  37  shown in FIG. 4 is formed being substantially continuous and common to both the first and second handle portions  27  and  33  respectively. The present invention wrench disclosed and shown here, has structural features which are substantially and significantly different than the prior art wrenches disclosed herein. 
     Referring now to FIGS. 6 and 7 together, FIG. 6 shows a cross-sectional, end view of the first handle portion  27  of the present invention wrench  21  shown in FIG.  3 . FIG. 7 shows a cross-sectional, end view of the second handle portion  33  of the present invention wrench  21  shown in FIG.  3 . When the wrench  21  is viewed from an end view thereof, the first and second handle portions  27  and  33  respectively, each have an elongated cross-sectional shape. Each cross-sectional shape is elongated in a distinct directions shown, and therefore, the direction of elongation may be used to compare the orientation of one handle portion to another or to an axis of wrench rotation. The elongated cross-sectional shape of the first handle portion  27  is positioned substantially perpendicular to the axis of wrench rotation  25  of the first wrench head, and substantially parallel to the axis of wrench rotation  31  of the second wrench head. And, the elongated cross-sectional shape of the second handle portion  33  is positioned substantially perpendicular to the axis of wrench rotation  31  of the second wrench head, and substantially parallel to the axis of wrench rotation  25  of the first wrench head. By positioning the handle portions to the wrench heads as shown, the wrench maintains an excellent accessibility to fasteners located in common and limited-access environments. 
     FIG. 8 shows a perspective view of another present invention double-ended wrench, whereas, double-ended wrench  41  has an undistorted, elongated handle  42 , comprising a first handle portion  44  and a second handle portion  43 . First handle portion  44  is connected to a first wrench head  45 , and, second handle portion  43  is connected to a second wrench head  46  as shown. It can be seen that elongated handle  42  has a side surface  48  extending in a longitudinal direction tapering towards the first wrench head  45 , and, an upper surface  49  extending in a longitudinal direction tapering towards the second wrench head  46 . Also, tapering side surface  48  is formed substantially continuous and common to both the first and second handle portions  44  and  43  respectively, and, the tapered upper surface  49  is formed substantially continuous and common to both the first and second handle portions  44  and  43  respectively. 
     FIG. 9 shows a left side, elevational view of another present invention, combination wrench with each wrench head being pivotably connected to a wrench handle portion, and one wrench head further having a ratcheting mechanism. A double-ended wrench  51  is shown comprising a first wrench head  53  positioned at one end of an elongated handle  71  and a second wrench head  61  positioned at the other end thereof. Wrench head  61  contains a ratcheting mechanism  65  therein to expedite the wrenching process of wrench  51 . Each wrench head has an orifice formed for engagement with various fasteners, with orifice  62  of wrench head  61  seen in this view. Each orifice has an imaginary central axis of wrench rotation. The first wrench head is positioned relative to the second wrench head whereas the axis of wrench rotation  55  of the first wrench head  53  is substantially perpendicular to the axis of wrench rotation  63  of the second wrench head  61 . The elongated handle  71  is formed substantially undistorted, and comprises a first handle portion  59  pivotably connecting to the first wrench head  53  with pivot axle  57 , and a second handle portion  69  pivotably connecting to the second wrench head  61  with pivot axle  67 . The first and second handle portions  59  and  69  respectively, each have an elongated cross-sectional shape when the wrench is viewed from an end view thereof. The undistorted, elongated handle  71  further comprises a side surface  72  extending in a longitudinal direction tapering towards the first wrench head  53 , and an upper surface (not seen in this view) extending in a longitudinal direction tapering towards the second wrench head  61 . The present invention, double-ended wrench may have two wrench heads which are the same type, or, two wrench heads which are different in type. Each wrench head may be fixed or pivotably connected to a handle portion of the wrench. Other embodiments of the present invention may include a ratcheting mechanism contained in one or both wrench heads to expedite the wrenching process. 
     When considering the present invention, simplicity and obviousness should not be confused or considered the same. Accordingly, the novelty and complexity of the present invention must be measured by the many interrelated objectives set forth herein, including accessibility, comfort, torque, strength, durability and ergonomic considerations. 
     Upon reading and understanding the specification of the present invention described above, modifications and alterations will become apparent to those skilled in the art. It is intended that all such modifications and alterations be included insofar as they come within the scope of the patent as claimed or the equivalence thereof.