Patent ID: 7013576

Claim:
A measuring device for measuring a size of an object, comprising: a body having a U-shaped frame with an anvil on a distal end of the frame; a spindle that is screwed into a proximal end of the body via a multiple-start thread and axially advances and retracts by screwing towards or away from the anvil; and a display means for displaying a measurement based on a detection signal from a detection means that detects axial displacement of the spindle from revolution of the spindle, wherein the detection means includes: a stator attached to the body; a rotor placed opposite to the stator; a fastening groove axially inscribed on the spindle; a fastening pin attached to the rotor, the fastening pin including a cylindrical body that includes a flat side with a spherical distal portion protruding from the flat side, the spherical distal portion fitting into the fastening groove; and a pressing means for pressing the fastening pin towards the fastening groove, wherein the pressing means is a plate spring, and the plate spring has one end secured by a screw for adjusting a biasing force of the plate spring, and another end that presses against the cylindrical body.