Abstract: A cathode sheath for a thermionic electron-gun cathode. The sheath is substantially in the form of a hollow cylinder and has an outer surface and an inner surface, a central axis, a closed end and an axially-opposite open end, and a side wall extending between the closed end and the open end. The sheath is a continuous bimetallic laminate having a first layer of material forming the inner surface and a second layer of electron-emission (donor) material overlying substantially the entirety of the first layer and forming the outer surface. The laminate has a preselected thickness at the closed end and has a thickness at the side wall which varies along the central axis. The outer surface of the bimetallic laminate is substantially unreactive with oxygen whereas the inner surface is more readily reactive with oxygen.

Abstract: An electron gun assembly includes a plurality of cathode assemblies and a plurality of spaced successive electrodes mounted on at least two electrically insulative support rods. At least one of the electrodes comprises a deep-drawn substantially rectangular cup-shaped member having a base portion, a supporting flange portion, including a plurality of attachment tabs, and a sidewall extending therebetween. The sidewall includes a plurality of coined welding areas that provide a substantially flat welding surface having structural rigidity for securing studs thereto to facilitate attachment of the electrode to the support rods.

Abstract: The heating unit for sealing vacuum electron tubes of the type having a glass stem, a glass exhaust tubulation extending from the stem and a plurality of electrically-conducting leads extending from the stem in a circular array around the tabulation includes a cylindrical heating coil within a coil recess of an electrically-insulating coil support. The coil recess circumscribes a central aperture within the coil support. The coil support has a first and a second surface with a coil-positioning lip projecting upwardly from the second surface thereof and circumscribing the central aperture. A hollow, substantially cylindrical, tubulation-locator having an outwardly extending flange formed in an outside surface thereof is disposed between the second surface of the coil support and a base plate. The locator also includes a centering collar formed in its outside surface and a tubulation centering aperture formed in the inside surface. A top plate is adjacent to the first surface of the coil support.

Abstract: An electron gun assembly for use in a color CRT includes a pair of insulating support rods, three inline indirectly heated cathode disposed between the support rods, a heater for each of the cathodes and a pair of improved, reinforced heater tabs. The heater includes a pair of heater legs which are attached to the heater tabs. Heater bead straps are provided for attaching the heater tabs to the support rods. The electron gun also includes a plurality of electrodes for focusing and accelerating an electron beam generated by the cathodes. The reinforced heater tabs comprise a main body portion including a first and a second part. Each of the parts is attached to one of the heater legs. Each of the heater tabs has a pair of outwardly directed feet each of which is connected to one of the parts of the main body portion by a pair of substantially orthogonal legs extending therebetween.

Abstract: The present invention provides an improvement in a color picture tube having an inline electron gun with coma correction members therein. The gun includes at least two electrodes that form a main focusing lens and a shield cup interconnected to one of the main focus electrodes. The improvement comprises the coma correction members being attached to the outside surface of the shield cup facing the main focusing lens electrodes. In a method of attaching the coma correction members to the shield cup, the members are provided as one of a plurality of sets of members in a continuous strip. One set of members are placed against the outside surface of the bottom of the cup and welded thereto. Portions of the strip that are not part of the welded members are broken-away from the welded members.

Abstract: An apparatus for manufacturing a glass stem for an electron tube comprises a first (upper) stem mold assembly and an improved second (lower) stem mold assembly. The improved second stem mold assembly includes a universal second (lower) stem mold having a plurality of lead-in conductor receiving openings formed therethrough. At least one removable stem mold plug is disposed and retained within one of the openings.

Abstract: An apparatus for manufacturing a glass stem for an electron tube comprises a first mold assembly and a second mold assembly for forming the stem therebetween. The glass stem includes a plurality of fillets with a lead-in conductor through less than all of the fillets and at least one dummy fillet without a lead-in conductor therethrough. The first mold assembly includes a universal stem having a mold block with fillet-forming openings therein. A replaceable marker pin is disposed and retained within the openings. The marker pin has a first end and an oppositely disposed second end. The first end has a distinctive geometric shape for contacting the dummy fillet and for conveying intelligible information thereto.

Abstract: An apparatus for manufacturing a glass stem for an electron tube has a plurality of lead-in conductors and a plurality of fillets with the lead-in conductors extending through the fillets. The apparatus comprises a first stem mold assembly and a second stem mold assembly for forming the stem therebetween. The first stem mold assembly comprises a universal stem mold having a plurality of longitudinal fillet-forming openings formed through a mold block. A plurality of inserts are replaceably disposed and retained within the openings in the mold block. Each of the inserts has a first end, an oppositely disposed second end, and a shank portion therebetween. Each of the inserts has a recess provided in the first end and a lead-accommodating opening extending from the recess into the shank portion of the insert. The mold block also accommodates one or more solid inserts in the openings to produce stems having dummy fillets, i.e., fillets without lead-in conductors therethrough.

Abstract: An apparatus used to manufacture a molded glass stem comprises a plurality of conventional lower stem mold assemblies and a plurality pre-heating, heating, forming, and annealing stations. The forming stations include at least one primary forming station having a primary upper stem mold assembly and at least one secondary forming station having a secondary upper stem mold assembly. The primary upper stem mold assembly includes a primary universal stem mold having primary fillet-forming means formed in a first mold block thereof. The secondary upper stem mold assembly includes a secondary universal stem mold having secondary fillet-forming means formed in a second mold block thereof. The primary fillet-forming means includes a plurality of longitudinal fillet-forming openings formed through the first mold block of the novel primary universal stem mold. A plurality of novel primary inserts are replaceably disposed within the openings in the first mold block.

Abstract: An electron gun assembly for use in a CRT includes a pair of insulating support rods, at least one indirectly heated cathode disposed between the support rods, a heater for the cathode and an improved heater tab. The heater includes a pair of heater legs which are attached to the heater tab. Heater bead straps are provided for attaching the heater tab to the support rods. The electron gun also includes a plurality of electrodes for focusing and accelerating an electron beam generated by the cathode. The improved heater tab comprises a main body portion including a first and a second part. Each of the parts is attached to one of the heater legs. The heater tab has a pair of outwardly directed feet each of which is connected to one of the parts of the main body portion by a pair of substantially orthogonal legs extending therebetween.

Abstract: A stem mold includes an improved first (upper) mold assembly and a conventional second (lower) mold assembly. The first mold assembly includes a conventional mold head and a plurality of lead-weights which are attached to one end of the mold head. The first mold assembly is improved by the inclusion of a novel first mold block which has a plurality of fillet recesses therein which communicate through guide openings with a plurality of buffer-pin-wells extending into a cavity in a second surface of the mold block. A novel lead-weight translator is disposed within the cavity in the mold block. The translator has a translator recess formed in one surface and a plurality of lead-weight apertures extending from the recess through the other surface of the translator. A pin holder is disposed within the translator recess. A plurality of pin apertures are formed through the pin holder and aligned with the buffer-pin-wells in the mold block and also with the lead-weight apertures in the translator.

Abstract: An electron gun assembly includes a plurality of cathode assemblies and a plurality of spaced successive electrodes mounted on at least two electrically-insulative support rods. At least one of the electrodes comprises a deep-drawn substantially rectangular cup-shaped member having a base portion, a supporting flange portion, including a plurality of attachment tabs, and a sidewall extending therebetween. The sidewall includes a plurality of reinforcing ribs formed therein which extend substantially from the supporting flange portion to the opposite end of the sidewall adjacent to the base. The reinforcing ribs minimize the flexure of the sidewall.

Abstract: The present invention is an improvement in an electron gun assembly. Such a gun assembly includes a plurality of indirectly heated cathode assemblies and at least two spaced successive electrodes having aligned apertures therein for passage of a plurality of electron beams. The cathode assemblies include a plurality of cathode heaters which are attached to at least two electrically insulating support rods by a plurality of heater bead straps. Each of the heater bead straps includes a main body portion having a distal end and a proximal end. The proximal end has a bifurcated portion comprising a pair of closely spaced apart grasping members for embedment into one of the insulating support rods. At least one member of the pair of grasping members is angulated with respect to the main body portion to increase the retention of the heater bead straps to the insulating support rods.

Abstract: An electron gun assembly includes a plurality of cathode assemblies and a plurality of spaced successive electrodes mounted on at least two electrically-insulating support rods. At least one of the electrodes comprises a deep-drawn substantially rectangular cup-shaped member having a base portion, a supporting flange portion, including a plurality of attachment tabs, and a sidewall extending between said base portion and said supporting flange. The sidewall includes a substantially wedge-shaped shoulder on each of the opposed side thereof that projects outwardly at an acute angle of about 45 degrees from the sidewall. The shoulders extend into the supporting flange adjacent to the attachment tabs. The shoulders form a gusset on each of the opposed sides of the cup-shaped member thereby increasing the structural rigidity of the member.

Abstract: Overcurrent protection is obtained in a push-pull network by circuitry repeatedly comparing signals indicative of the instantaneous current flow through the push-pull switching elements with a synchronized reference signal whose value is preferably made to decline during the ON periods of the current switches. Thus, the reference signal may initially be set relatively high to accommodate a moderately high in-rush transient and then to decline to lower levels over the remainder of the time the switching elements are on. At any time that the current signals exceed the compared to reference value, the corresponding current switch is deactivated as a protective measure.

Abstract: A glass support rod comprising a generally rectangular glass body with flat ends, at least two opposite edges at each of said ends having radii of at least about 0.375 millimeter (15 mils).

Abstract: A novel electron gun assembly having at least one generally longitudinally-extending electron beam path includes a plurality of electrodes attached to at least two electrically-insulating support rods. Each of the support rods has a surface having at least two indexing cavities formed therein for aligning the support rods along the beam path.

Abstract: A beading apparatus for an electron gun assembly having a plurality of self-indexing insulating support rods with a plurality of indexing cavities formed in a surface thereof comprises at least two bead blocks. Each of the bead blocks has a beading support surface with a plurality of apertures formed therein. An indexing pin is disposed in each of the apertures. Each of the indexing pins has a reference end which extends beyond the beading support surface and projects into the indexing cavities of the insulating support rods. A vacuum is applied to the support rods to retain the support rods in contact with the indexing pins. In a second embodiment a support foot is used in conjunction with the vacuum to retain the support rods in contact with the indexing pins.