Abstract: An electromagnetic voice coil actuator comprises a pot core magnet structure having a magnetic flux conductive core, a field coil within the pot core magnet structure for generating magnetic field through the magnetic flux conductive core and across an air gap, a voice coil disposed within the air gap. The voice coil and the field coil are each driven by an amplified signal derived from the audio input signal to create an actuation force, wherein the pot core magnet structure uses a soft magnet core.

Abstract: A multiposition switch, particularly suited for use as a motor speed controller, includes pairs of fixed contacts disposed in two parallel rows, and an arcuately shaped elongated movable contact. The movable contact rocks across successive pairs of the fixed contacts to make contact between a given pair of fixed contacts before contact is broken between a preceding pair. The movable contact is freely supported and rocked in response to forces exerted thereon by first and second rollers. The first roller is supported on a lever which is pivotable about a movable point so that as the lever is moved from an off position the first roller applies a force to the movable contact proximate a second end thereof. The second roller is supported on a pivotable member and applies a force to the movable contact proximate the first end thereof tending to return the contact to the off position.

Abstract: A signal transducing unit which is compact and can be calibrated from outside its housing to provide zero and span adjustments after assembly with the components secured within its housing. The device has a pair of first and second elements movable with respect to each other and each having first and second ends and a conductive path, and the conductive paths of the elements electrically contact each other at a location which is displaced along their paths with the relative movement of the elements. Positioning means retains the elements for relative movement, while actuating means displaceable for moving and positioning the first element with respect to the first element controls the contact location of the elements.

Abstract: A signal transducing apparatus comprising first and second elements movable with respect to each other and each having first and second ends and a conductive path, the conductive paths of the elements electrically contacting each other at a location which is displaced along their paths with the relative movement of the elements. A spring unit movably retains the second element having a first end fixed with respect to the first element and a second end secured with the second end of the second element, the spring unit urging the second end of the second element in a predetermined direction with respect to the first element and urging the first end of the second element in the direction toward the first element.

Abstract: A signal transducing device comprising a first element having a contact surface with a conductive path, a second element having an arcuate contact surface with an arcuate non circular conductive path and being movable with respect to and engaging by rocking action the contact surface of the first element, the conductive paths of the elements electrically contacting each other at a location which is displaceable along their paths with the movement of the second element. Positioning means retains the elements for relative movement and actuating means moves and positions the second element with respect to the first element and controls the contact location of the elements, while connecting means electrically joins with the conductive paths of the first and second elements for providing an output signal determined by the position of one element with respect to the other.