Process for the control of the forward speed of work-pieces

A machine with automatic feed speed control comprising, a work-piece advancing motor, a work-piece advancing roller connected to said work-piece advancing motor engageable with a work-piece for advancing it at a feed speed in a feed path, said advancing motor comprising a direct current motor having a power supply connected thereto, a semi-controlled bridge connected in said power supply of said advancing motor for controlling the speed thereof, a tooling motor, a tooling member connected to and rotatable by said tooling motor comprising a shaft and a plurality of axially aligned blades thereon extending in said feed path, a power line connected to said tooling motor, a transducer comprising a transformer having a primary winding connected to said power line of said tooling motor and a secondary winding, a plurality of sensors connected in parallel with each other and with said secondary winding of said transformer, each sensor comprising a sensing switch in series with a resistor, a rectifier in said secondary winding of said transformer, said secondary winding of said transformer connected to said semi-controlled bridge, said sensing switches extending across said feed path, whereby a work-piece advanced in said feed path closes a number of said sensing switches corresponding to the number of blades engaged with said work-piece for producing an impulse corresponding with a maximum load appliable to said tooling motor, said advancing motor being reduced in speed through said semi-controlled bridge by said transducer when an actual load on said tooling motor exceeds said maximum load determined by said plurality of closed sensing switches.