Abstract: The present invention is a pull-out distance arm for measuring both the diameter of a substantially circularly-shaped object and the distance of the plane of the circularly-shaped object from a fixed reference plane. The distance arm incorporates transducers that do not move when the arm is moved and, consequently, there is no movement in the wires connecting to the transducers, resulting in enhanced reliability.

Abstract: An improved sensor for detecting vibrations uses a flexible moving beam supported by two flexible leg members. The flexible moving beam can be moved in two directions. A protrusion extends from near one end of the flexible moving beam. The protrusion is placed against a transducer element 22 which is against a rest element 24 . When the moving beam is moved parallel to its length, the protrusion is pushed against the transducer element 22 and against the rest element 24, thereby generating electrical signals. When the moving beam detects vibrations in a direction perpendicular to its length, the protrusion is rotated upward and outward and pushes against the transducer element 22, causing the generation of electrical signal. The improved sensor is particularly adapted for detecting vibrations from a stringed musical instrument.

Abstract: A belt tensioning apparatus for tensioning a belt that extends between a driving shaft and driven shaft which are immovably supported with respect to one another. There is a flat spring, the free end of which bears against one run of the belt at a point between the two shafts. The opposite end of the spring is rigidly fixed so as to orient the spring within the plane of the belt such that the spring elastically deflects the belt run into a taut condition. A second leaf spring supported for cooperation with another belt run. Plural flat springs backing up the first mentioned springs for increasing the force applied thereby to the belt runs.