GB566777A - - Google Patents

Abstract

566,777. Arc lamps. PERRY, E. J., and WEBB, W. A. June 18, 1943, No. 9877. [Class 39 (i)] The carbon electrodes b, Fig. 1, of an arc lamp are mounted on holders C carried by a right- and left-handed screw spindle d and are automatically fed by an electric motor j which drives the spindle at a rate synchronized with the rate of consumption of the electrodes. A handle e is used to set the electrodes at the required distance, and a button p co-operates with a bracket c<1> on the holder c to switch off the current, through the wire o when the limit of electrode consumption has been reached. The driving connection between the motor and the spindle d is shown in Fig. 2. It consists of two arms l pivotally mounted on the spindle and carrying spring pawls g engaging a ratchet wheel f also mounted thereon frictionally. One arm l is connected by a link h to an adjustable crank on the motor shaft and the other arm is connected to the midpoint of the link by jointed links m. The adjustable crank consists of a pin h<6> carried eccentrically by a block h<2> which is angularly adjustable in an eccentric bore in a block h<1> formed on or fixed to the motor shaft.