Tool for torsion bar repair

Abstract

A method and tool assembly ( 10 ) for unloading and reloading spring energy from a torsion bar ( 11 ) in a torsion bar suspension system of a motor vehicle. The tool assembly ( 10 ) includes a generally C-shaped body ( 14 ) having a screw shall ( 24 ) threaded through a boss ( 22 ) in a lower section ( 18 ) thereof. An anti-rotation stem ( 38 ) includes a knurled flat face ( 40 ) which increases versatility of the tool assembly ( 10 ) by enabling anti-slip operation with various vehicle types. A counter-torque tool perch ( 46 ) extends from the lower section ( 18 ) of the tool body ( 14 ) for applying a counter-rotational torque to the body ( 14 ) during use of the tool assembly ( 10 ).

What is claimed is: 
     
         1 . A tool assembly comprising:
 a tool body having upper and lower sections, said body including a threaded boss formed integrally with said lower section;   a screw shaft threadably engaged in said boss and extending between leading and trailing ends, said screw shaft including an anvil at said leading end generally opposing said upper section of said body and a wrench receiving portion at said trailing end;   and a counter-torque tool perch extending from said lower section of said body for applying a counter-rotational torque to said body during use of said tool assembly.   
     
     
         2 . The tool assembly of  claim 1  wherein said counter-torque tool perch is laterally offset from said boss and includes at least two flat faces. 
     
     
         3 . The tool assembly of  claim 1  wherein said counter-torque tool perch has a generally hexagonal cross-section spaced apart from said boss. 
     
     
         4 . The tool assembly of  claim 1  wherein said body has a riser section extending between said upper and lower sections thereof, with said upper, lower and riser sections forming a generally C-shaped configuration. 
     
     
         5 . The tool assembly of  claim 1  wherein said screw shaft has a major diameter along its length, and said anvil comprises a generally cylindrical trunk having a diameter less than said major diameter and a hemispherical tip adjoining said trunk. 
     
     
         6 . The tool assembly of  claim 1  wherein said body includes a roughened surface along said upper section thereof. 
     
     
         7 . A tool assembly comprising:
 a tool body having upper and lower sections, said body including a threaded boss at said lower section;   screw shaft threadably engaged in said boss and extending between leading and trailing ends, said screw shaft including an anvil at said leading end generally opposing said upper section of said body and a wrench receiving portion at said trailing end; and   said body including a roughened surface along said upper section thereof, said roughened surface configured to prevent slippage during use of said tool assembly.   
     
     
         8 . The tool assembly of  claim 7  wherein said roughened surface includes an anti-slip stem having a knurled, generally flat face. 
     
     
         9 . The tool assembly of  claim 8  wherein said anti-slip stem has a generally frustoconical sidewall. 
     
     
         10 . The tool assembly of  claim 7  wherein said roughened surface includes a crisscrossing pattern of ridges. 
     
     
         11 . The tool assembly of  claim 7  wherein said roughened surface includes a plurality of concentrically oriented ridges. 
     
     
         12 . The tool assembly of  claim 7  wherein said screw shaft defines a longitudinally extending axis and wherein said axis intersects said roughened surface. 
     
     
         13 . The tool assembly of  claim 7  further including a counter-torque tool perch extending from said lower section of said body and laterally offset from said boss. 
     
     
         14 . The tool assembly of  claim 13  wherein said counter-torque tool perch has a generally hexagonal cross-section. 
     
     
         15 . The tool assembly of  claim 7  wherein said body has a riser section extending between said upper and lower sections thereof, with said upper, lower and riser sections forming a generally C-shaped configuration. 
     
     
         16 . The tool assembly of  claim 7  wherein said screw shaft has a major diameter along its length, and said anvil comprises a generally cylindrical trunk having a
 diameter less than said major diameter and a hemispherical tip adjoining said trunk. 
 
     
     
         17 . A method for disabling an adjusting bolt in a torsion bar suspension system in a motor vehicle, said method comprising the steps of:
 providing a torsion bar suspension system having a loaded torsion bar, an adjusting arm affixed to one end of the torsion bar and sheltered within a hollow frame rail, with an adjusting member operatively disposed between the adjusting arm and the frame rail;   providing an unloader tool having a body with an upper section and a lower section, and a screw shaft threaded through the lower section;   positioning the upper section of the tool body over the frame rail; locating the screw shaft of the unloader tool against the adjusting arm; transferring spring energy sway from the adjusting member to the unloader tool by turning the screw shaft relative to the body so that the screw shaft pushes the adjusting arm away from the adjusting member; and   applying a counter-torque to the body of the unloader tool simultaneously with said step of transferring spring energy away from the adjusting member to the unloader tool.   
     
     
         18 . The method of  claim 17 , therein said step of applying a counter-torque includes centering the counter-torque at a location laterally offset from the screw shaft. 
     
     
         19 . The method of  claim 17 , wherein said step of centering the counter-torque at a location laterally offset from the screw shaft includes engaging a wrench with a counter-torque tool perch having at least two flat faces. 
     
     
         20 . The method of  claim 17 , wherein said step of positioning the upper section of the tool body over the frame rail includes depositing an anti-slip stem in a hole in the frame rail. 
     
     
         21 . The method of  claim 11 , wherein said step of positioning the upper section of the tool body over the frame rail includes placing a roughened surface against the frame rail.