Abstract: A steelmaking furnace is cleaned and maintained using a lance which includes an elongated lance body including at least one first nozzle opening proximal to an end that extends into the furnace and at least one other second nozzle opening spaced upwardly from the first nozzle opening. Structure defines at least one passageway extending through the body to the first nozzle opening and to the second nozzle opening. Gas supply means selectively introduces different gases into the passageway. The lance apparatus can be operated to emit either different gases or the same gas from the first and second nozzle openings at the same time. The gases emitted include an oxygen-containing gas and a gas that includes an inert gas.

Abstract: A method of making stabilized ultra-low carbon steel having a high nitrogen content for enameling applications. The preferred method involves two phases. The first phase occurs in the basic oxygen furnace wherein nitrogen gas is combined with oxygen gas and blown into the melt through the oxygen lance. After the oxygen blow the carbon content of the melt is approximately 0.03% and the nitrogen content is at least about 0.016 to 0.020%. In the second phase the melt is introduced to a vacuum circulation decarburizer where the carbon content of the steel is reduced to ultra low levels on the order of 0.005%. The nitrogen content is maintained at a level of at least about 0.01% by introducing nitrogen gas into the vacuum decarburization vessel as the lift gas through inert gas tuyeres.

Abstract: A key switch assembly for direct mounting on a PCB or similar substrate. The key switch has a body with depending mounting pin having retainers thereon to secure the key switch at apertures in the substrate. The key switch body has a hinged key and includes a snappable dome moveable from a non-actuated position to an actuated position in direct contact with conductive elements in the substrate by manual depression of a key.

Abstract: A key switch assembly for direct mounting on a PCB or similar substrate. The key switch has a body with depending mounting pin having retainers thereon to secure the key switch at apertures in the substrate. The key switch body includes a snappable dome moveable from a non-actuated position to an actuated position in direct contact with conductive elements in the substrate by manual depression of a key.

Abstract: A key switch assembly for interposition between a PCB and a cover plate for actuating a contact element such as a snap dome. The key switch includes a body having a cantilever actuator arm hingedly secured to the body. The body is located with respect to the cover plate by means of an upwardly extending dowel pin. The underside of the actuator arm carries a generally cylindrical striker element which when the arm is depressed engages the snap dome in line contact. The upper surface of the actuator arm has a mounting projection which projects through an aperture in the cover plate and is adapted to receive a key cap. Manual pressure applied to the key cap will cause the actuator arm to pivot about hinge section bringing the striker element into contact with the snap dome.

Abstract: A logical control system is provided for accommodating both single and double byte accesses to a video terminal system display memory to supply video character and visual attribute data to a video screen without limiting the quantity of visual attributes and without the needless occupation of video screen character positions by visual attribute characters.

Abstract: A logic memory control system for accommodating plural read/write requests to a video terminal display memory is provided without the need for multiplexing common busses shared by the video terminal logic devices accessing the display memory, or for compromising video terminal data transfer rates.

Abstract: A logic system is provided in a video system for accommodating the display of both video data characters and graphic characters, and the application of visual attributes to such characters whether occurring singularly or in fields.

Abstract: A logic system is provided in a video system for accommodating the display of both video data characters and graphic characters.

Abstract: A logic system is provided in a video system for accommodating the display of video data characters and the application of visual attributes to such characters whether occurring singularly or in fields.

Abstract: A logic control system in a video display terminal is disclosed for synchronizing the operation of dual, asynchronously operating CRT control unit semiconductor chips to accommodate a substantially increased number of visual attributes per display row with minimal effect on data character transfer rates.

Abstract: A logic control system for a video display terminal is disclosed for accommodating vertically and horizontally varying entry points to a video memory to acquire first character bytes of rows of video information for display on a CRT screen. Dynamically changeable display page snapshots of the video memory, and the formation of display pages from randomly located rows of video information within the video memory are thereby provided.