A rotary solenoid, particularly for use in electronic teleprinters and the like, especially for attachment perforators, etc., in which most of the metal components may be fabricated in the form of stamped sheet metal structures rather than turned or machined components and which is relatively readily adaptable to automatic fabrication, the stator poles being in the form of stamped sheet metal laminations disposed in respective aligned stacks at opposite ends of an actuating coil and provided with respective bearing members, for the armature, disposed at the outer faces of the respective pole stacks, with each bearing member having an inwardly directed bearing boss extending into the adjacent stack and in engagement with the respective pole faces thereof to axially align the armature in operative position. The respective pole stacks are operatively connected by a pair of yoke plates, likewise formed as sheet metal stampings and extending between and connecting the respective pole stacks to effect a closing of the magnetic circuit of the rotary solenoid.
A mechanism using a stepping motor as the prime mover for a bar code printing head or hammer mounted on the end of a pivotal lever. Where the output code (such as the postal code used in the U.S.) requires a full bar as one binary indication and a half bar the other binary indication, two motors each with its own printing head are used. The heads are spaced apart longitudinally relative to an object to be printed. A full bar is made up of two half bars, thus, both motors must be energized at separated time intervals to cause both heads to strike in a single transverse alignment to print a full bar. The lever supporting the printing head is constructed to position its center of percussion essentially in alignment with the printing hammer to minimize wear on the motor shaft.
A solenoid plunger for use in solenoid driven multi-line embossing systems is constructed of magnetic steel laminations that are attached to a center block which is machined to mount a solenoid shaft and anti-rotate pins. The laminations are attached to the center block with screws and vacuum epoxy glued for a very high cycle life. The laminated steel construction dramatically reduces eddy currents, which allows the magnetic field to rise and fall much more quickly than a conventional steel plunger. It also increases the magnetic force in the solenoid. This reduction in solenoid plunger eddy currents and increase of magnetic force in the solenoid structure itself operates to increase embosser throughput. The laminated steel construction further reduces embosser solenoid heating which also contributes to improved embossing control.
A method and apparatus for a two-pulse solenoid embossing system implementing an amplitude feedback circuit, i.e., current monitor (48), to provide precise amplitude and timing control over two current pulses (4, 5), and thereby provide precision control over the position and velocity of the embossing system's print elements (64a, 64b). To maintain the current amplitude during the second current pulse (5), the method and apparatus alternatively switches the power on and off to the solenoid coils (55) with a frequency such that a substantially constant current amplitude is maintained in the solenoid coils (55). The embossing system provides an improved solenoid body assembly (61) including a first stack of steel laminations (93), a center block (82) and a second stack of steel laminations (81). A plunger (62) is slidably connected to the solenoid body assembly (61) by shaft (63). Cavities (79) receive dowel pins (71) which are attached to plunger (62). The cavity and dowel pin arrangement (79, 71) prevents the plunger (62) from rotating.
