Torque testing instrument for tools, especially spanners

Claim 1

A torque testing instrument for tools such as spanners, wrenches and the like, said instrument being connectable to a reading device and comprising: (a) a measuring assembly and a means for transmitting measured values from the measuring assembly to said reading device, (b) means for holding a tool while being subjected to torque effect force, (c) load sensing means for producing an electrical charge signal constituting measured values proportional to the torque effect force being transmitted, (d) said load sensing means including a piezoelectric load sensing element, (e) said means for transmitting measured values including means for electrically connecting the load sensing element to an electronic amplifier for the reading device, (f) said measuring assembly including a measuring head having a holding fixture and a plate member which functions as a lever arm, (g) said plate member being rigidly connected with an intermediate member rotatably disposed on a base plate means, said intermediate member being mounted to rotate about a pivot point on the measuring head, (h) said means for holding including a holding fixture effective to hold the tool to be tested and being located at one end of the plate member which transmits said torque effect force to said piezoelectric sensing element, (i) said piezoelectric sensing element being provided laterally of the plate member at the other end thereof to receive said torque effect force in a direction transverse to said plate member, (j) said load sensing means being supported on a block secured to said base plate means.