Abstract: A gold alloy for use in a dental restoration, and which maintains a true yellow-gold color after being cast and having a porcelain jacket fired thereon. The alloy is 83-87% gold, 7-12% platinum, 1.5-3.0% rhodium, and less than 1.0% copper. Other elements are included for grain refining, strength, formation of bonding oxide for the ceramic jacket, and the like.
Abstract: A dental crown form or strip crown for holding and shaping a body of composite resin material being applied to an anterior tooth requiring restoration. The crown form is a thin hollow body with an interior surface conforming to the shape of a natural tooth. A tab is integrally formed at the base or gingival end of the crown form, and the tab extends away from the base to provide a gripping handle for the crown and a surface for displaying a designation of the tooth of intended use. A flange is integrally formed around the base to strengthen and rigidify the crown form which is preferably made of co-polyester plastic.
Abstract: A radiant furnace for firing ceramic material provides for accurate control over the rate of increase of the ceramic material temperature during a firing operation. Heat is radiated in the furnace from an electrically controlled heater. A first programming signal is produced to represent a manually selected rate at which the temperature is to be raised, and a second programming signal is produced to represent a manually selected target temperature beyond which the ceramic material temperature is not to be raised. Circuitry responsive to the first and second programming signals produces a command signal varying in magnitude to define a ramp having a peak value. The command signal is applied to a closed-loop heating control subsystem employing a thermo-sensitive transducer for providing a feedback signal.
Abstract: Apparatus for controlling the operation of a pivoted member. A pivoted arm such as provided in an apparatus for bonding leads in electronic components is controlled by means of a torque motor during bonding and non-bonding intervals to provide control of forces exerted by the pivoted member during the bonding interval and forces exerted on the pivoted member during non-bonding intervals. Motion cams to complement the operation of the torque motor may also be utilized.
January 16, 1974
Date of Patent:
February 24, 1976
Joseph L. Laub, David W. Steinmeier, II