Abstract: An electric toothbrush having a detachable brush head assembly including a driven shaft that is driven by a driveshaft disposed with in a housing. The driveshaft is part of or secured to a torsion bar that supports an armature including a pair of magnets. An electric coil receives an alternating flow of current at a predetermined frequency that causes the magnets to be alternately attracted to the coil and causes the torsion bar to oscillate in an oscillatory rotary motion.

Abstract: An electric toothbrush having a detachable brush head assembly including a driven shaft that is driven by a driveshaft disposed with in a housing. The driveshaft is part of or secured to a torsion bar that supports an armature including a pair of magnets. An electric coil receives an alternating flow of current at a predetermined frequency that causes the magnets to be alternately attracted to the coil and causes the torsion bar to oscillate in an oscillatory rotary motion.

Abstract: A magnetic core structure for a transducer head of the type used in digital data storage devices is wider on one side of the magnetic gap (e.g., the write side) than it on the other side of the gap (e.g., the read side), to provide "wide write-arrow read" recording and reproducing capabilities. Magnetic flux return during recording (writing) operations is accomplished through the comparatively narrow read core plus additional magnetic closure elements which are disposed alongside, and which magnetically shunt, the read core, such that the overall core structure has basically the same width on each side of the magnetic gap. Improved transducing performance is provided by using additional thickness for such magnetic shunts and recessing the end extremity of the latter adjacent the gap at the face of the head, where the head accesses the magnetic recording media, such that the overall magnetic reluctance of the magnetic returns (i.e., shunts) is lowered but the effective gap width of the head is not changed.

Abstract: A miniaturized tape cartridge drive for data processors in accordance with the invention has as peripherally-enclosing main frame providing an access opening for insertion to a tape cartridge and structurally mounting flat, pancake-type drive motors for tape transport and head-positioning translation laterally with respect to the tape, for accessing any of a plurality of adjacent recording tracks on the tape, such motors being disposed in tandem with respect to the cartridge-admitting opening and having their output shafts pointing in opposite directions. The head-positioning motor drives a directly-coupled rotary cam, and a positioning arm extends between the cam and the transducer head to move the head in response to movement of the cam. The positioning arm is pivotally journaled in opposite sides of the main frame upon a transverse pivot axis disposed medially of the arm, such that the arm operates as a fulcrumed lever.

Abstract: Apparatus and method for decoding of transducer head-positioning information which has been recorded on data-storage media, in particular magnetic tape, and for use of the decoded information to position a transducer head, wherein the transducer head reads the recorded information and its output signals are sampled at predetermined times to determine their magnitude and a digital representation of such magnitude is obtained by timing an interval during which a reference source increases at a known rate from a first value to a second value whose difference corresponds to the detected magnitude of the transducer output signals. The timed interval is outputted in the form of a digital count value which is thus representative of the head-positioning information read out from the data storage media, and the digital signal provided by such count value is then used in positioning, or repositioning, the transducer head in a representative manner.