Locking pliers with improved adjustment member

Abstract

A hand tool includes a first jaw, a first handle fixed to the first jaw, a second jaw, and a second handle pivotally coupled to the second jaw, a link member, and an adjustment member. The adjustment member is operable to axially move a first end of the link member to vary a distance between the first and second jaws. The adjustment member includes an engagement surface engageable with the first end of the link member, a shank in threaded engagement with a bore in the first handle, and a flange extending from the shank opposite the engagement portion. The flange includes a substantially planar first side, a substantially planar second side opposite the first side, and an elongate opening extending through the first and second sides.

What is claimed is: 
     
         1 . A hand tool comprising:
 a first assembly including a first jaw and a first handle fixed to the first jaw, the first handle having a bore at an end opposite the first jaw;   a second assembly pivotally coupled to the first assembly, the second assembly including a second jaw and a second handle pivotally coupled to the second jaw;   a link member having a first end axially movable along the first assembly and a second end pivotally coupled to the second assembly; and   an adjustment member operable to axially move the first end of the link member along the first assembly to vary a distance between the first and second jaws, the adjustment member including
 an engagement surface engageable with the first end of the link member, 
 a shank in threaded engagement with the bore, the shank defining a longitudinal axis, 
 and a flange extending from the shank opposite the engagement portion, the flange including
 a substantially planar first side, 
 a substantially planar second side opposite the first side, and 
 an elongate opening extending through the first and second sides, 
 
   wherein the elongate opening defines a first diameter coaxial with the longitudinal axis and a second diameter perpendicular to the longitudinal axis,   wherein the first diameter is greater than the second diameter.   
     
     
         2 . The hand tool of  claim 1 , wherein the adjustment member is integrally formed as a single piece. 
     
     
         3 . The hand tool of  claim 1 , wherein the elongate opening is sized to receive a screwdriver shank therethrough. 
     
     
         4 . The hand tool of  claim 1 , wherein a ratio of the second diameter to the first diameter is between about 0.4 and about 0.9. 
     
     
         5 . The hand tool of  claim 1 ,
 wherein the adjustment member defines an overall length measured from the engagement surface to an end of the flange opposite the engagement surface,   wherein the flange defines a thickness measured between the first and second sides,   wherein the flange defines a flange length measured from the end of the flange to the shank, and wherein the flange defines a flange width measured perpendicular to the thickness and the flange length.   
     
     
         6 . The hand tool of  claim 5 , wherein the thickness is between about 4 millimeters and about 9 millimeters. 
     
     
         7 . The hand tool of  claim 5 , wherein a ratio of the flange length to the overall length is between about 0.2 and about 0.7. 
     
     
         8 . The hand tool of  claim 5 , wherein a ratio of the flange width to the flange length is between about 0.4 and about 1.4. 
     
     
         9 . The hand tool of  claim 5 , wherein a ratio of the first diameter to the flange length is between about 0.2 and about 0.8. 
     
     
         10 . The hand tool of  claim 5 , wherein a ratio of the second diameter to the flange width is between about 0.2 and about 0.8. 
     
     
         11 . The hand tool of  claim 1 , further comprising a first grip overmolded on the first handle and a second grip overmolded on the second handle. 
     
     
         12 . The hand tool of  claim 11 , wherein at least one of the first grip and the second grip includes a first material and a second material, the second material being softer than the first material. 
     
     
         13 . The hand tool of  claim 1 , wherein the first jaw and the second jaw are made of chrome plated forged alloy steel. 
     
     
         14 . A method of clamping a workpiece between first and second jaws of a hand tool, the hand tool having a first assembly including the first jaw and a first handle fixed to the first jaw, a second assembly pivotally coupled to the first assembly and including the second jaw and a second handle pivotally coupled to the second jaw, a link member having a first end axially movable along the first assembly and a second end pivotally coupled to the second assembly, and an adjustment member having a threaded shank defining a longitudinal axis and a flange, the method comprising:
 pivoting the second handle towards the first handle to move the second jaw toward the workpiece;   inserting a shank of a screwdriver through an elongate opening in a flange of the adjustment member; and   applying force to the screwdriver to rotate the adjustment member, thereby axially moving the first end of the link member along the first assembly to move the second jaw further toward the workpiece and to increase a clamping force applied to the workpiece by the first and second jaws.   
     
     
         15 . The method of  claim 14 , wherein the elongate opening defines a first diameter coaxial with the longitudinal axis and a second diameter perpendicular to the longitudinal axis, wherein the first diameter is greater than the second diameter. 
     
     
         16 . The method of  claim 15 , wherein the ratio of the second diameter to the first diameter is between about 0.4 and about 0.9.