Loop fault sensing means for web transport systems

Claim 1

IN A CHAMBER SYSTEM FOR ESTABLISHING TAPE LOOPS, A PROTECTION ARRANGEMENT FOR PREVENTING TAPE DAMAGE INCLUDING THE COMBINATION OF LOST LOOP SENSING MEANS INCLUDING A SINGLE PRESSURE SENSITIVE SWITCH, MEANS DEFINING A RELATIVELY LARGE SHORT LOOP SENSING APERTURE OPEN TO ATMOSPHERE AT ONE LENGTHWISE POSITION ALONG THE CHAMBER, MEANS DEFINING A RELATIVELY SMALL LONG LOOP SENSING APERTURE AT ANOTHER LENGTHWISE POSITION ALONG THE CHAMBER, AND MEANS COUPLED TO THE CHAMBER FOR PROVIDING A PRESSURE DIFFERENTIAL ACROSS THE TAPE LOOP, THE LONG LOOP SENSING APERTURE MEANS BEING ABOVE THE PRESSURE DIFFERENTIAL MEANS AND THE PRESSURE SENSITIVE SWITCH BEING COUPLED TO THE LONG LOOP SENSING APERTURE FOR SENSING PRESSURE DEVIATIONS THEREAT WHENEVER THE LOOP RISES ABOVE THE SHORT LOOP SENSING APERTURE OR FALLS BELOW THE LONG LOOP SENSING APERTURE.