Zenith Radio Corporation

Zenith Electronics Corporation

Melvin F Rogers

Lawrence W Dougherty

Sae D Lee

A CRT implosion protection system having a resin system releasably bonding an implosion panel to the faceplate of a flat or concave CRT and a tension band system secured around the periphery of the faceplate which exerts compression thereon. The tension band system includes a pair of keeper bars which prevent the tension band from slipping, and which secure an external magnetic shield to the CRT.

Flat tension mask cathode ray tube implosion system

Improved mounting and implosion-protection means and method are disclosed for use in a cathode ray tube having a substantially rectangular glass face panel with a rearwardly extending skirt. A first tension band has a predetermined relatively wide width for compressively inwardly loading the panel at a tension level completely effective to protect against implosion. Four mounting brackets, one at each corner of the panel for mounting the tube, have a rearwardly extending foot. A second tension band substantially narrower than the first band circumscribes and overlays the first band. The second band is tensioned at a level 55 to 78 percent of the tension level of the first band for capturing and compressively holding each bracket foot against the first band. The effect according to the invention is such that the tension level of the second band is effective to retain the mounting brackets, but ineffective to deleteriously interfere with the implosion protective tension exerted on the panel by the first band.

CRT Mounting and implosion-protection means and method

This disclosure depicts an implosion-protected, rectangular-type color cathode ray tube bulb comprising a rectangular glass faceplate of the type having a viewing window and a flange extending rearwardly therefrom, to which flange is sealed a mating funnel. The bulb has a tension band system very tightly constricting said flange so as to provide implosion protection for the bulb by compressively pre-loading the corners of the faceplate flange. The bulb is characterized by having on the outside of the faceplate flange at each corner and molded integrally with the flange, an incompressible load-concentrating boss for significantly reducing the corner area on which the load is applied by the tension band. By this expedient, the level of the compressive stresses generated in the flange at the flange corners and the resultant implosion protection provided by the tension band system is greatly enhanced.

Rectangular color cathode ray tube bulb with integral corner bosses for

This disclosure depicts a novel system for implosion protecting a color television picture tube having a faceplate with a rearwardly extending side surface and a mating funnel. The system is illustrated as comprising, in part, a high tensile strength frame which surrounds and overlies at least a portion of the side surface of the faceplate and which is cemented to the faceplate. The system further comprises a crack retarder which is located about the circumference of the tube, but which is spaced axially rearwardly from the frame. The system assists in retaining in position the shards of a shattered faceplate and also assists in retarding the propagation of cracks in the tube, thereby providing for a relatively gradual buildup of pressure in the tube.

Color television picture tubes with improved implosion protection system

This disclosure depicts a novel edgebond system for implosion protecting a color television picture tube having a flangeless faceplate. The edgebond system is illustrated as comprising in its most general sense a high tensile strength metal contoured frame, preferably having a substantially constant depth around the faceplate, which is cemented to and binds up the edge surface of the faceplate, i.e., the thickness dimension of the faceplate. The system assists in retaining in position the shards of a shattered faceplate and thereby provides for a relatively gradual buildup of pressure in the tube.

This disclosure depicts a novel edgebond system for implosion protecting a color television picture tube having a flangeless faceplate and a mating funnel. The edgebond system is illustrated as comprising, in its most general sense a high tensile strength metal scalloped frame which is cemented to and binds up a portion of the funnel and also the edge surface of the faceplate, i.e., the thickness dimension of the faceplate. The system assists in retaining in position the shards of a shattered faceplate and thereby provides for a relatively gradual buildup of pressure in the tube and provides for a maximum overlay of the funnel and a maximum volume of cement at the center of the sides of the funnel to provide greatest implosion protection at portions of the tube where greatest protection is needed.

Method for reducing the likelihood of cathode ray tube glass bulb and bulb component fracture which are caused by temperature cycling in the cathode ray tube manufacturing process and which are associated with defects in the glass. Temperature gradients between glass exterior surfaces and glass interior, arising during cooling, are locally reduced. In a preferred embodiment, a thermal insulator is applied prior to or during cooling, over a defect and its vicinity in order to locally reduce the rate of surface cooling and thus locally reduce the cooling-induced surface tensile forces. An improved component-in-process is depicted which has a reduced susceptibility to thermally induced fracture.

Method for reducing thermally induced fracture in cathode ray tube bulbs

This disclosure depicts, for use in salvaging parts from a color television cathode ray tube of the type having a glass bulb comprising an approximately rectangular, flangeless, curved faceplate and a funnel having a convex seal land, a novel method for separating the funnel and the faceplate. The funnel seal land mates with a concave rear surface of the faceplate to define a contoured sealing interface. The faceplate is sealed to the funnel with a frit material located at the sealing interface. The method comprises establishing the bulb at a predetermined initial temperature; concurrently down-shocking (effecting a sudden cooling of the surface of) the faceplate and the corner regions of the funnel for a predetermined brief period of time, causing separation at the sealing interface of the faceplate from the corner regions of the funnel; then down-shocking the side regions of the funnel near the sealing interface for a predetermined brief period of time while continuing to down-shock the faceplate and the corner regions of the funnel, to cause a complete separation of the faceplate from the funnel at the sealing interface.

Method of separating a funnel and flangeless faceplate of a color

Method for reducing the likelihood of cathode ray tube glass bulb and bulb component fracture caused by temperature cycling during tube salvage. The depicted salvage method includes heating and then cooling the exterior surfaces of a glass front panel and glass funnel to be separated, thus producing a temperature gradient between the front panel extreme border and more remote inner portions of the front panel extreme border. This temperature gradient causes circumferential tension at the front panel extreme border. The circumferential tension is reduced to thus lessen, the likelihood of front panel fracture by applying, prior to or during, said cooling, a thermal insulator over the front panel extreme border and vicinity so as to locally reduce the rate of glass surface cooling.

Growing community of inventors

Western Springs, IL, United States of America

Melvin F Rogers