Abstract: Vacuum interrupters having an improved axially movable terminal assembly are provided for use in vacuum circuit breakers or similar protective devices. The improved movable terminal assembly includes an axially movable but non-rotatable internal terminal portion in contact with an axially movable and rotatable external terminal portion adapted for connection in a vacuum circuit breaker or the like. This arrangement allows the external terminal portion to rotate and twist during installation or adjustment of the vacuum interrupter in a circuit breaker device and prevents transmission of torsional stress to the internal terminal portion.

Abstract: An arc stalling eliminating electrode having a sealed vacuum cylinder within which are a pair of confronting electrodes disposed within the cylinder and mounted for movement between a first closed position in which the electrodes have contact faces which engage one another and a second open position in which the contact faces are spaced apart. The confronting electrodes move between the first and second positions when a high voltage AC current appears across the electrodes in order to interrupt that current. The interrupted current generates an arc between the electrodes until it goes to zero. The electrodes are configured such that the arc generated during separation of the electrode faces is caused to move to an outer periphery of the electrodes and around the latter with substantially no stalling in its movement, whereby the possibility of damaging the electrodes and the arced metal vapor due to the arc is minimized.

Abstract: Vacuum interrupters having improved structural rigidity and internal vacuum integrity are provided for use in vacuum circuit breakers. Due to the design and construction of the endcap assemblies, the vacuum interrupters require a reduced total length of brazed seams, and the incidence of vacuum loss due to faulty seams is thereby reduced. An improved stationary terminal assembly including a reinforcing member providing increased structural rigidity is also provided.

Abstract: An electrical power protection technique which is especially suitable for use in three-phase high voltage switch gear applications is disclosed herein. This technique utilizes an electrically insulated housing for each phase of the electrical circuit. Each housing contains a fuse intended for placement in circuit with the switch gear and a source of high voltage and has an entry door for gaining access to the fuse from outside the housing. Each fuse is disengagably connected to a power terminal, outside the housing through a utility opening in the latter. The terminal is, in turn, connected in circuit with the source of high voltage and switch gear. A component interlock assembly is provided for automatically disconnecting each fuse from its terminal and thereafter closing the cooperating utility opening sufficient to physically shield the terminal from its fuse when the entry door is opened.

Abstract: A spring-powered drive assembly for opening and closing a switch such as one forming part of a high-voltage switch gear apparatus is disclosed herein along with its method of operation. The apparatus includes a drive arm which is adapted for connection with the switch to be opened and closed and movable in response to a certain minimum force from a first position to a second position, whereby to open the switch, and from the second position back to the first position, whereby to close the switch. The power required for moving the drive arm between these two extreme positions is provided by means of a single straight coil spring charged and discharged in one specific way to move the drive arm in one direction and charged and then discharged in a second way to move the drive arm in the opposite direction.

Abstract: A switch assembly especially suitable for use as part of an overall electrical circuit breaker is disclosed herein. This switch assembly includes a three-link arrangement consisting of three links interconnected together for movement between a first positional configuration in order to open a circuit and a second positional configuration in order to close and circuit. A mechanism is provided for applying a force to the linkage arrangement in a way which causes the links to open from a closed position, that is, to move from their first positional configuration to their second positional configuration, and thereafter for maintaining the links in their open configuration.

Abstract: A switching apparatus for disconnecting and connecting power between a power source and a load employs a vacuum switch, a knife blade or air switch coupled electrically in series with the vacuum switch and a positive interlock mechanism. In the disconnect mode, at first the bias on a springloaded movable contact of the vacuum switch is relieved; then the vacuum lock that maintains the movable contact engaged with the fixed contact in the vacuum switch is overcome to cause complete separation of the contacts, thereby breaking the connection to the power source; and finally the knife blade is moved to open the air switch and to a position providing a visual indication that the power to the load has been interrupted. A continuous force is applied to the interlock mechanism, but the disconnect process occurs sequentially in three steps. During the connect mode, the three step process is reversed.

Abstract: A leak sensor powered directly by the circuit voltage being controlled by the vacuum circuit interrupter and continuously operating while the interrupter is in service. An indicating system is connected to the leak sensor, or sensors, and provides an indication of failure and corrective action to be taken in single phase or multi-phase circuits.

Abstract: A vacuum breaker operator in which a breaker closing drive spring is charged by a charging mechanism including a drive lever mounted on a drive shaft coupled to compress the spring as the lever is rotated. A drive gear is rotatively mounted on the drive shaft. Coupling means couple the drive gear to rotate the drive shaft to rotate the lever and charge the spring during a charging operation and decouple the driven gear during a spring discharging operation. A drive linkage is coupled to said spring and serves to close the breaker when the spring is discharged. An opening spring is coupled to said drive lever linkage and adapted to be charged by the drive spring and provides the energy for opening the breaker. A reciprocating pawl drives the driven gear from a power source and means are provided for disengaging the pawl when the drive spring is charged allowing the pawl to engage the gear when the spring is discharged whereby the gear can be rotated to recharge the drive spring after a discharging operation.