Abstract: A spring charging mechanism for electrical circuit breakers and transfer switches of the type in which a spring is charged by rotation of a shaft. The charging mechanism has a charging shaft with two independently operating ratchet mechanisms coupled thereto. One ratchet mechanism may be driven by hand while the other may be separately motor-driven or held stationary by a bracket. The ratchet mechanism which is not in operation acts as a locking device which prevents rotation of the charging shaft in the discharge direction while allowing rotation in the charging direction. The charging mechanism is adaptable for either hand or motor-driven operation or both. It also features an inexpensive and easily-installed flexible, resilient, insulating sleeve which insulates the charging mechanism from the operator, and a key arrangement for coupling a handle to a ratchet mechanism which distributes stress within the handle and protects the handle fastening screws from destructive shear stresses.

Abstract: A circuit breaker having a contact movable between open and closed positions, includes a closing spring assembly having a closing spring and first and second brackets. The closing spring assembly is chargeable when in a reset position in which the first bracket is hooked by a first hook. The closing spring is charged, manually or electrically, with support of the second bracket being transferred to a second hook. The closing spring is discharged to close the circuit breaker, with the closing spring assembly moving from the reset position to a discharged position in the process. The closing spring assembly is then moved as an integral unit, back to the reset position, with the closing spring again being charged, enabling the circuit breaker to immediately reclose in the event of a trip due to a transient condition. An improved breaker operating mechanism and power operated charging mechanism, are also disclosed.

Abstract: A circuit breaker, and method of constructing same, in which a levering-in mechanism may be added after the circuit breaker has been assembled. The circuit breaker includes a chassis having first and second side plates which define upwardly open slots, which enable the levering-in mechanism to be "dropped in" to the correct position of an assembled circuit breaker, with bottom portions of the slots functioning as half bearings. First and second retainer plates with downwardly open slots are respectively attached to the first and second side plates, to complete the half bearings and hold the levering-in assembly. The levering-in mechanism includes a threaded shaft having a traveling nut, with a bushing on the shaft being held radially, but not axially, by a bracket member, with the bushing also functioning as a non-stress stop for the traveling nut.

Abstract: A circuit breaker having a trip actuator which mechanically trips the breaker in response to an electrical trip pulse. The trip actuator includes first and second parallel magnetic circuits, with the first circuit having a lower reluctance than the second circuit. A magnet provides magnetic flux for both circuits. A pivotally mounted clapper has a first position in which it is releasably held in the first circuit by a magnetic force, and a second position. Bias springs urge the clapper towards the second position, with the bias springs providing a biasing force which is less than the magnetic force holding the clapper. The electrical trip pulse creates a magnetic flux which opposes the magnetic flux in the first circuit, switching the magnetic flux to the second circuit. The clapper member pivots to the second position, and a trip link associated with the clapper actuates a trip mechanism.

Abstract: A circuit breaker having a chassis, an electrical contact structure, and a shock absorber mechanism. The contact structure includes a movable first electrical contact and a second electrical contact. The first contact has a first movement range. The shock absorbing mechanism, which absorbs energy from the movement of the first contact, includes a metallic bar pivotally mounted on the chassis, and first and second limit members fixed to the chassis. The first and second limit members define a second movement range which overlaps the first movement range. A spring weakly biases the metallic bar towards the second limit member. The first contact, during movement thereof to an open position, strikes the metallic bar. Kinetic energy is removed from the first electrical contact by the metallic bar without bounce of the electrical contact, and the metallic bar pivots against the first limit member, transferring the shock of stopping the first contact to the chassis.

Abstract: A power circuit breaker having movable and relatively stationary contact assemblies operable between open and closed positions. The contact assemblies respectively include pivotally mounted first and second conductive members. The first and second conductive members are disposed in spaced relation in the closed position of the circuit breaker, to provide a first current loop having first and second legs defined by said first and second conductive members. A pivotable mounting arrangement for the second conductive member provides a second current loop defined by the second leg portion of the first loop and a third leg portion. The magnetic forces in the first current loop, which tend to pivot the second leg portion towards the third leg portion, are opposed by magnetic forces in the second current loop. Compression spacers provide parallel current paths which reduce the magnitude of current flowing through a pivotable joint of the relatively stationary contact assembly.

Abstract: A grounding switch device for a metal-clad switchgear is adapted to be inserted into a standard circuit breaker cell allows the bus and line conductors within the switchgear assembly to be grounded for maintenance. A plurality of fixed and selectable test ports are provided to facilitate various electrical tests. The ground switch device is disposed on a frame and contains a ground contact assembly for providing sliding contact between the ground switch device and the ground bus within the circuit breaker cell. The ground contact assembly is in electrical contact with a movable contact. The movable contact is adapted to engage a stationary contact mounted on a mounting plate, attached to the frame by way of an insulator. A selector switch assembly connects the stationary contact to either the upper bus terminals or line terminals in the metal-clad switchgear assembly. The contact portion of the movable contact is U-shaped having two spaced-apart blades.

Abstract: A circuit breaker characterized by a voltage-responsive device having an electromagnet including an armature. A linkage connects the armature to the trip latch of the circuit breaker in order to open the circuit breaker contacts when a voltage occurs that is less than a predetermined voltage value. Under normal operating conditions, when the contacts are closed, the armature is retained in place by an electromagnetic force, but is biased away therefrom when the voltage drops below that voltage value.

Abstract: The kinetic energy generated by the rapidly moving contact and coupled operating mechanism of a tripped circuit breaker or similar apparatus is dissipated by a compressible shock-absorbing assembly comprising a loose stack of freely-movable magnetized metal plates which is mounted in laterally-extending position on a stationary upstanding part of the breaker and is struck by a lever fastened to the main operating shaft of the breaker operating mechanism. The metal plates are freely movable toward and away from one another and are so magnetized that adjacent plates repel one another. The plates are accordingly normally spaced from each other and produce a series of sequentially-occurring impacts and collisions between the plates and the advancing striker lever when the breaker is tripped.

Abstract: Overheating of the contacts and associated current-carrying parts of a vacuum type circuit breaker is prevented by fastening a U-shaped heat exchanger component of non-magnetic sheet metal to a protruding portion of the stem that is located at the top of the breaker bottle and is integral with the stationary contact. The U-shaped heat exchanger component is secured in inverted position on the stationary stem and the downwardly-extending skirts of the heat exchanger are slotted to provide a series of spaced ribs which form planar grid structures that allow ambient air to flow through the heat exchanger component and enhance its heat transfer characteristics.

Abstract: The kinetic energy generated by the rapidly moving contact and coupled operating mechanism of a tripped circuit breaker or similar apparatus is dissipated by a compressible shock-absorbing assembly comprising a loose stack of metal plates and interposed springs which is mounted on a stationary part of the breaker and is struck by a lever fastened to the main operating shaft of the breaker operating mechanism. The metal plates are movable toward and away from one another due to the resiliency of the springs and the resulting multiple impacts between the plates and advancing striker lever produces a momentum exchange phenomenon which quickly dissipates the kinetic energy and brings the breaker operating mechanism and movable contact to a smooth stop. The compressible multiple-impact assembly provides a compact shock absorbing means that is especially adapted for use in medium voltage circuit breakers (5 to 35 KV rating) of various types which is not only durable and efficient but very inexpensive and reliable.

Abstract: There is provided by this invention a vacuum monitoring device for use in vacuum circuit interrupters comprising a stacked resistor assembly as a voltage divider coupled to an internal shield of the vacuum bottle and a low voltage detection circuit for monitoring leakage currents under abnormal pressure conditions.

Abstract: Vacuum circuit interrupter apparatus is taught in which a movable stem is interconnected with one of the separable main contacts thereof. Flat planar flexible conductors connected in parallel circuit relationship between the stem and a fixed terminal for the circuit interrupter system are utilized. Planar members are spaced from each other for enhanced heat dissipation characteristics. Furthermore, the planar members are generally self-supporting except for the flexibility associated with a particular shape, consequently are not likely to randomly touch other apparatus in a switchgear cabinet. Nevertheless, the amount of conductor represented by the parallel planar members is sufficient to conduct electrical current when the circuit interrupter is closed.

Abstract: Electrical apparatus and more particularly vacuum electrical circuit breaker apparatus is taught. The electrical apparatus has a cylindrical movable terminal stem which is to be interconnected with a fixed terminal by way of a flexible conductor which is nevertheless relatively stiff and self supporting. This is accomplished by using interlayered elongated rectangular plates or sheets between the two aforementioned terminals. Connection to the circular stem is made by utilizing offset tabs around the periphery of a central hole at one end of each of the sheets. The offset allows the tabbed opening to be inserted over the stem. After which the tabs are sandwiched or compressed to lie in the plane of the sheet thus causing the edges of the tab to flow around the stem reducing contact resistance. Because there are multiple sheets in each flexible conductor packet, the number of three point contacts between the flexible conductors and the stem is increased.

Abstract: A single barrel puffer circuit interrupter is taught. The single barrel accomplishes the multiple purposes of electrical insulation between terminals, basic support and puffer gas containment. The circuit interrupter has a movable nozzle-piston arrangement fixedly attached to a movable cylindrical hollow arcing contact. The nozzle slidably engages a second cylindrical, hollow arcing contact and is disposed in slidable but sealed relationship therewith at all times, thus providing a shield between the arcing contact and the barrel of the circuit interrupter. In addition, one of the arcing contacts overlaps the other in telescoping relationship when the contacts are closed. This provides a lost motion feature for the puffer. The lost motion feature allows the puffer gas to be compressed for a short period of time by the piston during a contact opening operation in a completely enclosed region before the gas is provided to the region of an electric arc between the opening contacts.

Abstract: A gas-blast circuit-interrupter of the "puffer" -type has a pair of separable contacts, at least one of which is movable, and a movable multiple insulating arc-shield assembly, or multiple hollow nozzle assembly, is movable during the opening operation with said movable contact, and initially delays the radial inward ejection of compressed gas from the piston chamber into the arcing region, until an adequate time has elapsed for sufficient arc lengthening to take place for circuit interruption.

Abstract: A puffer circuit interrupter is taught. Arc extinguishing gas is vented through a hollow stationary arc contact into a gas condenser. The gas condenser is an elongated toroid having a well-defined open central region. The gas condensing portion of the toroid is formed from overlapping layers of wound copper mesh. The elongated central opening of the toroid is aligned with the hollow electrode for receiving the arc quenching gas. At one end of the condenser is an external conductor for the puffer circuit interrupter. At the other end of the condenser is a disc having a central opening therein through which the hollow electrode protrudes. The condenser is thus firmly maintained longitudinally between the disc and the external electrode. Surrounding the circumferential periphery of the condenser and bridging the space between the disc and the electrode are longitudinally disposed circumferentially spaced fingers. The spaced fingers form a support cage for the condenser.

Abstract: A single barrel puffer circuit breaker apparatus is taught in which compressed sulfur hexafluoride gas is forced into the region of an arc. The arc is struck between hollow, cylindrical conductors during a circuit breaker opening operation. The heated gas is exited from the region of the arc by way of the internal portion of the hollow conductors. At the other ends of the hollow conductors the gas is vented into enlarged regions which are partially bounded by the single barrel. The single barrel provides the multiple functions of support, insulations and gas storage. Gas coolers are provided, one of which may cool the hot gase as it radially diffuses therethrough and the other of which may cool hot gas as it transversely diffuses therethrough. The coolers tend to reduce the energy of the gas by reducing its temperature and consequently its pressure, thus assisting in protecting the inner surface of the single barrel from charring and protecting the entire barrel from rupturing.

Abstract: A quick-acting movable-column tripping device is provided as an optional feature of either circuit-interrupters, supported by upstanding insulating column structures, or, alternatively, in connection with circuit-interrupters having a serially-related disconnecting switchblade, providing a visible open-circuit gap, so that a minimum of time is utilized in a tripping operation of the circuit-interrupter. Otherwise, there would be a considerably-delayed action caused by the normal, or inherent lost-motion provided in the loose linkages, which normally are used to effect operative movement of the movable relatively massive supporting column structure.The quick-acting, accelerating tripping device of the present invention provides relative fast motion between the upstanding rotatable supporting column structure and a base-spindle device, the latter of which is operatively mechanically linked to the motor-operated mechanism, for example, of the switch structure, which may be relatively slow in operation.

Abstract: An improved operating mechanism of the energy-storage type is provided for circuit-interrupting structures, including an energy-storing means having the energy content therein increased by the movement of a movable member during the closing operation, and a collapsible toggle-linkage is provided between the energy-storing means and the separable arcing contact structure of the circuit-interrupter structure. Improved means are provided for a tripping operation, and thereby effecting the collapse of said toggle-linkage to effect the opening of said separable contact structure, and a second releasing means is preferably provided for discharging the stored-energy of the energy-storing means to effect thereby the straightening of said toggle-linkage and the consequent closing of the separable contacts within the circuit-interrupter during the closing operation.