Abstract: The disclosure relates to a cam disc and to a spring deflection switch having a cam disc for a spring-loaded drive, wherein the cam disc includes a first, second and third circumferential region, each having at least one corresponding radial extension, for actuating a pushbutton including a switching hysteresis. The at least one second radial extension is larger than the at least one third radial extension, which in turn is larger than the at least one first radial extension. The pushbutton can interact with the cam disc in the spring deflection switch such that when the pushbutton is applied by the first circumferential region, the switching contact assumes a first switching position, and when the pushbutton is applied by the second circumferential region, the switching contact assumes a second switching position, and when the pushbutton is applied by the third circumferential region, the switching contact remains in the switching position assumed earlier.

Abstract: A transfer switch configured particularly for use with traffic signal controllers, to enable a traffic signal controller to be powered by a portable electrical generator, when utility line power is unavailable. A housing, configured to be mounted either on the surface of a traffic signal controller cabinet, or recessed into an opening of the cabinet, so as to be flush to the surface thereof, is provided. The housing is configured to be substantially weatherproof without requiring the use of gaskets.

Abstract: Molded case electric power switches such as circuit breakers, disconnects and transfer switches have an energy storage spring which rotates a cam assembly to close and initiate opening of the switch contacts. The cam assembly includes a drive cam with a cam lobe which engages a drive cam follower on the moving contact assembly. Due to space limitations, the cam assembly is positioned so that the drive cam follower initially moves toward the cam assembly during closing. To accommodate for this, the cam lobe has a generally radial leading edge to prevent binding of the drive cam follower. A single latch mechanism latches the cam assembly in a spring charged position and in a closed position. A Y-shaped latch member has one leg which is engaged by a latch, a second leg which engages stops on the drive cam at the charged position and the closed position, and a third leg which sequentially engages the stops to reset the latch mechanism.

Abstract: The large close spring in the operating mechanism of electrical switching apparatus is charged by a charging mechanism which includes a charging cam mounted on a cam shaft and rotated by a ratchet wheel. An elongated handle is mounted for rotation about a pivot axis offset laterally from the cam shaft. A drive link which successively engages the teeth on the ratchet wheel is pivotally connected to the handle at a point closer to the handle pivot axis than the radius of the ratchet wheel to increase the mechanical advantage of the handle. A common spring biases the drive link and a stop dog against the ratchet wheel. A turned pin on the drive link is used to engage the ratchet teeth which have an arcuate profile including a radius at the root configured to be engaged by the turned pin. A similar drive link with a turned pin to engage the ratchet teeth is reciprocated by an electric motor.

Abstract: Disclosed is a switching device for a tap changer comprising an input lever and an output lever rotatably attached to a shaft. The output lever is provided for making contact with a selected one of a first tap and a second tap. The output lever has a cammed surface at its base for securing a position of the output lever to make contact with the first tap and for preventing the output lever from rotating about the shaft. The device also includes a spring for pulling the output lever toward the input lever, and a clutch, rotatably attached to the shaft, which has a slot. A latching apparatus engages the clutch. The device further includes a pin which is fixedly attached to the input lever and disposed within the slot. The pin drives the clutch to engage the latching apparatus. In operation, after the input lever has been pulled away from the output lever by a predetermined angle, the pin drives the clutch to engage the latching apparatus, thereby freeing the cammed surface from the latching apparatus.

Abstract: A mechanism for accumulating and storing mechanical energy, wherein the energy is used to close the primary contacts of a circuit breaker. The energy can be input to the mechanism manually or by means of a motor. The mechanism includes a series of linkages which function to utilize the energy to close the primary contacts. These linkages also function to maintain the closing force upon the primary contacts, while also functioning to allow rapid contact opening when desired.