Abstract: Gas filled surge arrester is equipped with a thermally responsive short circuit switch for overload protection and air gap shorting for back up overload protection. The switch and air gap device is disclosed in three orientations; namely, separate and external to the gas tube; unitized with the air gap interior to the switch; and unitized with the air gap exterior to the switch. The unitized arrangements have application in circuitry with gas tubes where back up air gap protection of the thermal switch is desired.

Abstract: A protector for a communications line comprises a three electrode gas tube surge voltage arrester as a primary protective device and metal oxide varistors as additional protective devices. In series with each side of the line, is an inductor that serves to isolate the gas tube from the varistors at relatively fast rise times of transient overvoltages. The gas tube, the varistors and the inductors are all mounted in a single housing that is divided into adjacent sections by an insulating member. The gas tube is in one section and the inductors and varistors are in the other section, the inductors being side-by-side and each coaxial with a pin that is adapted to be connected to the line.

Abstract: A surge voltage arrester assembly comprises a primary gas tube surge arrester and an air gap secondary arrester that provides surge protection should the gas tube become vented to atmosphere. The secondary arrester has the air gap defined by a rim of one of the gas tube electrodes and a metallic cup into which the gas tube is positioned. In a three element version of the invention wherein the gas tube has two line electrodes and a ground electrode, metallic cups are provided at opposite ends of the gas tube to cooperate with the ground electrode for forming secondary air gaps for each line electrodes. An O-ring and a sealing compound seals each secondary air gap against the entrance of contaminants.

Abstract: A device, for protecting electrical equipment and appliances from electrical surges, having: male prong members to connect the device to an electrical outlet; a female receptacle to receive a plug of the equipment or appliance; current diverting means including a varistor and thermofuse for interrupting current at the female receptacle upon the occurrence on the line feeding the outlet of transient voltage spikes and surges exceeding a predetermined voltage level. The electrical outlets include power outlets and telephone connectors of the multi-prong or coaxial type. Equipment which may be protected by an embodiment of this device includes devices e.g. recorders, computer terminals, which may be connected to the telephone lines.

Abstract: A conventional automatic electric circuit breaker is combined with a varistor to provide both overcurrent and overvoltage circuit protection. The varistor is connected between the load end of the circuit breaker and neutral to shunt to ground the currents associated with lightning induced voltage surges. As a fail-safe feature, abnormal leakage current drawn by the varistor under normal line voltage conditions directly and/or indirectly heats the thermal element of the breaker trip unit, ultimately tripping the breaker.

Abstract: A gas tube arrester protector used in protecting a pair of telephone lines from high voltages or surge currents includes a three electrode gas tube overvoltage arrester having a ground electrode adapted to be coupled to ground potential through a ground lead, a pair of line electrodes, each of which is adapted to be coupled to one of the pair of telephone lines through a terminal line or lead, a flat, generally U-shaped line contact and a fusible link coupled between the line contact and the line electrode. The gas tube arrester is positioned in an insulating housing or shell by disposing the line contact in slots formed by ribs on opposed walls of the housing and by positioning in grooves formed peripherally about an open end of the housing overlapped spacers having overlapping slots to receive the ground and terminal leads. The open end of the housing can be further sealed with an insulating material.

Abstract: An elongated line protector has a series of base modules for plug-in reception of a series of arrester modules, carbon or gas tube type as may be selected. Along opposed sides of the base modules are recesses for slide-on attachment of terminal modules each having a row of terminals, such as binding posts, connector clips, etc. for connections to telephone lines to be protected. Several groups of terminal modules may be assembled with each other side-by-side on each of the opposed base module sides depending upon the number of groups and styles of terminals desired. Correct electrical connections between the terminals and the arresters are established through the protector upon assembly by conductors including ground and line busses.

Abstract: A short circuit clip with legs for resiliently engaging a line and ground electrode of a gas tube arrester includes an air gap device at one set of legs. The air gap device includes a conductor member extending from the clip to contact an arrester electrode and insulated from the clip by a layer of insulation having a hole to form the gap. The air gap device may be releasably connected with the clip or permanently attached. In the former case, a ferrule housing, which acts as an electrode for the air gap, is fitted to the clip. In the latter, the conductor is a rivet which attaches the device to the clip. Non-metallic fusible elements are interposed between the clip legs and associate arrester electrode.

Abstract: A unitary line surge protector for removable connection to an individual, existing type-444 connecting block and jack assembly of a main distribution frame of a telephone exchange system at a telephone office or substation. Each connecting block and jack assembly includes a pair of normally closed jacks interposed between connecting lugs and a guide extension running generally parallel to the jacks. The line surge protector includes generally flat housing of electrically insulative material containing a pair of line surge protection devices. The housing has apertures that receive the jacks of the assembly, and interior contacts open the jacks and connect them through the protection devices. The dimensions of the housing are such that the protectors can be mounted adjacent one another both vertically and horizontally on a type-444 frame.

Abstract: Apparatus for protecting low voltage lines of a telephone system and including a jack block which may be mounted on a circuit breaker means having separable contact blades and such jack block has protecting elements including a plug with a plurality of contact studs that may be selectively inserted between the contact blades of the circuit breaker means.

Abstract: Disclosed herein is a three-element gas tube fail-safe station protector of known design modified to incorporate a back-up air gap system. To the ground terminal stud of the protector is added a lateral conductive member defining a pair of blade-shaped ground electrodes. To each of the line electrode terminal studs is added a conductive blade-shaped electrode which overlaps and is spaced from a respective one of the ground electrodes. The air gaps which are thus defined between ground and each line, i.e. paralleling the gas tube gaps, are encapsulated and dimensioned to provide back-up ionization in the event of a failure of the gas tube.

Abstract: In a device for housing a surge diverter having electrodes formed as cup-shaped recesses when viewed from the outside of the diverter, provision is made for an angled metal strip which engages the diverter at one end by means of a cylindrical rolled section which form-locks in the recess.

Abstract: A device for protecting electrical appliances from electrical surges having male prong members to connect the device to an electrical wall outlet; a female receptacle to receive a plug of the appliance; a self-restoring, current diverting spark gap means for interrupting current at the female receptacle at a predetermined voltage level.

Abstract: A temperature sensitive-trip device for use on an electrical surge arrestor and comprising a resilient contact member mounted on the arrestor and having a fusible material solidified in contiguous relationship therewith to hold contact member biassed so that on melting of fusible material, contact member is urged to a position in which it shorts the electrodes of the arrestor.

Abstract: A line protector includes a body having first and second end terminals and an intermediate terminal for connection to a ground potential. End caps are mounted on the end terminals and have peripheral edges maintained spaced from the intermediate terminal by means of a displaceable element responsive to excessive currents in the line being protected. High currents will cause the end caps to move toward the intermediate terminal and provide a short circuit therewith to ground to protect telephone equipment connected thereto. The intermediate terminal is mounted in a clip which has centering means formed therein to maintain the mechanical and electrical spacing of the intermediate terminal with respect to the end caps equal to one another. The protector assembly is mounted with a standard housing and base structure to be interchangeable with existing central office plug-in protectors.

Abstract: A circuit interrupting device comprising a vacuum fuse having an evacuated envelope wherein one or more fusible elements electrically connect spaced open ends of aligned tubular electrodes which have respective sealable ends external of the envelope and provide means for facilitating assembly and processing of the fuse.

Abstract: A terminal block carries a plurality of terminals, a plurality of end clips connected to certain of the terminals, and a pair of ground clips. The terminal block is provided with cavities for receiving surge-protector gas tubes which are engaged by the end clips and ground clips.

Abstract: A line voltage surge protecting device for telephone systems which normally include means for grounding excessive currents caused by lightening and the like. The device includes a gaseous discharge element which becomes conductive when the voltage in the line being protected momentarily exceeds a predetermined value to conduct current to a source of ground potential. A temperature sensitive element responsive to heat generated by the gaseous discharge device during prolonged excessive current serves to short the gaseous discharge element to ground. The temperature sensitive element includes means resiliently biasing the gaseous element for movement serving to short the same. A soldered retaining means opposes such movement, and heat developed in the gaseous discharge device is transmitted to the soldered means by conduction to melt the solder to permit the shorting action to occur.

Abstract: A gas tube arrester subassembly for use in a modular component type telephone central office protection system includes a gas tube arrester having a spacer tube with an electrode at each end. One of the electrodes is insertable into an open end of a generally cylindrical shell portion of the gas tube arrester subassembly with parts of the shell portions at the open end being swaged to form securing members to maintain the one electrode in the shell portion. The other end of the shell portion is closed with a generally rectangular slot therein. Removably mounted in the slot is a conductive U-shaped spring member such that the spring member has one leg extending along the inner surface of the closed end. Disposed between the one leg and the one electrode is a conductive disk-shaped contact member to couple the one electrode to the spring member.