Abstract

To evaluate the quality of a torquing operation wherein a tool engages a workpiece and exerts a rotational driving force on the workpiece until a predetermined maximum torque is attained between the workpiece and the tool, the time during that torquing operation in which the torque actually being exerted by a tool on the workpiece exceeds the maximum torque previously exerted by the tool on the workpiece during the torquing operation is recorded. This value is then compared with previously established minimum and maximum values at such time as to detect an improper torquing action. The apparatus for recording this time includes a sensor connected to the tool which generates the signal proportional to instantaneous torque being exerted. A peak detector follows this signal as it increases and stores a value equal to the maximum torque previously exerted by the tool on a workpiece during the torquing operation. This value is compared with the instantaneous torque and the counting operation is enabled whenever the actual torque being exerted exceeds the previous maximum torque.