Collapsible torque wrench

A collapsible torque wrench comprising:

• a shank;
• a drive head being disposed at a front end of the shank;
• a first pivoted end and a second pivoted end being disposed at a rear end of the shank and spaced from each other by a certain distance;
• a connection rod, a front end of the connection rod being pivotally connected with the first pivoted end of the shank, whereby the connection rod is angularly displaceable relative to the shank;
• a housing having a tubular body and a casing fixedly disposed on one side of the tubular body, the connection rod being relatively slidably fitted in the tubular body, a rear end of the connection rod extending into the tubular body;
• at least two pinholes being formed on a circumference of the tubular body;
• the casing having an internal receiving space;
• a torque adjustment mechanism including a fixing block, at least one elastic member and an adjustment member;
• the fixing block being a hollow sleeve;
• at least two insertion holes being radially formed on a circumference of the fixing block;
• the fixing block being mounted in the tubular body;
• a predetermined number of pin members being respectively inserted in the pinholes of the tubular body and the insertion holes of the fixing block to fix the fixing block with the tubular body;
• the rear end of the connection rod extending through the fixing block;
• a front end of the adjustment member being screwed with the rear end of the connection rod;
• the elastic member being mounted in the tubular body, two ends of the elastic member respectively abutting against the fixing block and the adjustment member;
• a stop member, a body of the stop member being formed with a locating slot, the stop member being received in the casing, a front end of the stop member being pivotally connected with the second pivoted end of the shank, whereby the stop member is angularly displaceable within the casing;
• a restriction member being disposed in the casing to extend into the locating slot of the stop member;
• and
• the first pivoted end of the shank and the front end of the connection rod forma sandwich pivot structure including two lugs spaced from each other and a middle section positioned between the two lugs;
• a through hole passing through the two lugs;
• a pivot hole being disposed on the middle section, the pivot hole having a diameter larger than that of the through hole;
• a relatively soft collar being mounted in the pivot hole;
• a pivot pin being fitted through the through hole of the two lugs and the pivot hole of the middle section;
• at least one end of the pivot pin being tightened with a wall of the through hole of at least one of the two lugs;
• the collar being positioned between the pivot pin and the pivot hole.