Abstract: A pulse control circuit for a d.c. series motor having an armature and two oppositely-wound field windings, comprises a contactor in series with the motor, two main thyristors each connected in series with the armature and a respective one of the field windings, means for controlling the mark-to-space ratio of conduction of each thyristor, one or other of the main thyristors being brought into operation in dependence upon the desired direction of drive of the armature, means for sensing failure of commutation of the main thyristor, and means for causing opening of the contactor in response to such sensing. The control circuit includes means for firing the other main thyristor immediately commutation failure is sensed, thereby to limit the net field flux and motor torque in the period during which the contactor is opening.

Abstract: A shanked innersole with laminated construction having a rigid street side layer, shank attached to foot side surface of the street side layer, shank board layer extending from heel to ball of innersole and a flexible layer attached to rigid street side and shank board thereby sandwiching the shank board between the top and street side layers so that only the shank attaching means are exposed on one side of the innersole construction.

Abstract: A bubble-blowing device enabling the formation of bubbles considerably larger than has been possible heretofore with less expenditure of energy, and further characterized by absence of moving parts, simplicity of operation, low cost and production of a greater number of bubbles per charge of bubble-blowing solution.