Photoelectric automatic speed regulator for conveyor

Claim 1

A CONTROL DEVICE FOR CONTROLLING THE LENGTH OF A FESTOON OF NEWLY FORMED, UNCURED, HIGHLY EXTENSIBLE MATERIAL TRAVELLING IN A SUBSTANTIALLY HORIZONTAL PATH AT A VARIABLE SPEED FROM A FORMING DEVICE TO A TAKE-AWAY CONVEYOR, A VARIABLE SPEED DRIVE FOR SAID TAKE-AWAY CONVEYOR, A ABLE SPEED DRIVE BEING RESPONSIVE TO A CHANGE IN VOLTAGE SUPPLIED THERETO, A FESTOON CONTROL DEVICE POSITIONED BETWEEN SAID FORMING DEVICE AND SAID TAKE-AWAY CONVEYOR TO CONTROL THE VOLTAGE SUPPLIED TO SAID VARIABLE SPEED DRIVE, SAID FESTOON CONTROL DEVICE COMPRISING A PLURALITY OF LIGHT SOURCES ARRANGED ON A VERTICAL PLANE ON ONE SIDE OF THE PATH OF TRAVEL OF SAID MATERIAL IN SAID FESTOON AND A PLURALITY OF PHOTOCELLS ARRANGED ON A VERTICAL PLANE ON THE OPPOSITE SIDE OF THE PATH OF TRAVEL OF SAID MATERIAL, THE ARRANGEMENT BEING SUCH THAT EACH PHOTOCELL IS IN ALIGNMENT WITH A LIGHT SOURCE AND THE BEAMS OF LIGHT FROM THE PLURALITY OF LIGHT SOURCES TO THE PLURALITY OF PHOTOCELLS PASS THROUGH THE VERTICAL PLANE THROUGH WHICH THE FESTOON RISES AND FALLS, SAID LIGHT SOURCES AND SAID PHOTOCELLS BEING ARRANGED IN A TOP GROUP AND BOTTOM GROUP WITH ONE INTERMEDIATE LIGHT SOURCE AND PHOTOCELL, EACH PHOTOCELL BEING CONNECTED TO A LINE TO SAID VARIABLE SPEED DRIVE; EACH PHOTOCELL IS CONNECTED TO A TRANSISTOR IN SERIES WITH SAID LINE TO SAID VARIABLE SPEED DRIVE; THE TRANSISTORS IN THE TOP