Zenith Radio Corporation

Admiral Corporation

Roy Maskell

Armando V Marino

Richard H Cowles

Thomas P De Franco

Robert B Feinberg

An article of manufacture comprising a cathode ray tube is disclosed for use in a projection television system. The tube has a funnel and a face panel with a window for receiving a rectangular imaging screen. The projection television system includes tube receptacle means having conjugate means for accepting the tube in proper rotational alignment. The tube according to the invention is characterized by having two pairs of substantially radially oriented embossments on the funnel. The embossments are centered on, and azimuthally spaced one hundred and eighty degrees apart, on a diametrical line about forty-five degrees in counterclockwise rotation with respect to the minor axis of the rectangular imaging screen. The pairs of embossments according to the invention provide for engagement with the conjugate means of the tube receptacle means for proper rotational alignment of the tube in the system.

Projector television tube alignment means and method

This disclosure depicts a method of spot-knocking an electron gun having a heater and cathode, a control grid G1, a screen grid G2, and four main focus lens electrodes (G3, G4, G5, and G6), wherein a first relatively large gap exists between G2 and G3, between G3 and G4, between G4 and G5, and between G5 and G6, and a second relatively small gap exists between G1 and G2, and a third relatively very small gap exists between G1 and the cathode. The method of this invention involves: establishing the heater and cathode and, the G1 and G2 grids and the G3, G4 and G5 electrodes at substantially ground potential; applying a first fluctuating DC voltage to electrode G6 of a magnitude and for a time effective to cause arcs to occur between portions of the electrodes G5 and G6 so as to remove any particles of metal or contaminants on the electrodes; whereby the grounding of the heater and cathode, the G1 and G2 grids and the G3, G4 and G5 electrodes protects the heater and cathode, and the G1 and G2 grids from arcs caused by the first fluctuating DC voltage; establishing the heater and cathode, the G1 and G2 grids and the G4 electrode at substantially ground potential; applying a second fluctuating DC voltage with an amplitude less than the first fluctuating DC voltage, to electrodes G3, G5 and G6, of a magnitude and for a time effective to cause arcs to occur between portions of the electrodes G4 and G5, between portions of the electrodes G4 and G3, and between portions of the electrodes G2 and G3 so as to remove any sharp particles of metal or contaminants on portions of the G2, G3, G4 and G5 electrodes; whereby the grounding of the heater and cathode and the grounding of the G1 and G2 grids protects the heater and cathode from arcs caused by the second fluctuating DC voltage.

Method of spot-knocking an electron gun assembly in a color television

Three substantially L-shaped bimetallic brackets accurately secured to the frame of a color television picture tube undergo corrective flexures in response to temperature variations. These flexures compensate for the thermal expansion of the shadow mask by maintaining the mask in proper alignment between the glass panel and the electron source over the operating temperature range of the picture tube.

Growing community of inventors

Oak Park, IL, United States of America

Roy Maskell