Register control for printing continuous metal strip

Claim 1

IN APPARATUS FOR PRINTING IMPRESSIONS UPON A CONTINUOUS STRIP OF SUBSTANTIALLY STIFF MATERIAL SUCH AS METAL BY MEANS OF AN IMPRESSION ROLLER WHICH IS MOUNTED AT A FIXED LOCATION ALONG A DEFINED PATH OF LENGTHWISE TRAVEL OF THE STRIP AND WHICH IS CAUSED TO ROTATE IN ENGAGEMENT WITH THE STRIP AS THE LATTER IS MOVED PAST SAID LOCATION, MEANS FOR CONTINUOUSLY MAINTAINING THE ANGULAR POSITION OF THE IMPRESSION ROLLER IN A PREDETERMINED RELATIONSHIP TO THE LENGTH OF STRIP THAT HAS BEEN PASSED IN ENGAGEMENT WITH IT, REGARDLESS OF VARIATIONS IN THE SPEED OF STRIP TRAVEL AT SAID LOCATION, SO THAT THE SUCCESSIVE IMPRESSIONS MADE BY THE IMPRESSION ROLLER ARE AT EXACTLY PREDETERMINED INTERVALS ALONG THE LENGTH OF THE STRIP, SAID MEANS COMPRISING: MEANS FOR MOVING A STRIP LENGTHWISE ALONG SAID DEFINED PATH; VARIABLE SPEED DRIVE MEANS FOR ROTATABLY DRIVING THE IMPRESSION ROLLER INDEPENDENTLY OF ITS ENGAGEMENT WITH THE STRIP AND HAVING A SPEED CONTROL ELEMENT BY WHICH ROTATIONAL SPEED OF THE IMPRESSION ROLLER CAN BE REGULATED; A MONITOR ROLLER MOUNTED FOR PERIPHERAL ENGAGEMENT WITH THE STRIP, TO BE ROTATABLY DRIVEN THEREBY, AT A MONITORING STATION AT WHICH THE LOCAL LINEAR SPEED OF THE STRIP ACCURATELY REFLECTS ITS LOCAL LINEAR SPEED AT SAID LOCATION; A PAIR OF ELECTRICAL INSTRUMENTALITIES, EACH HAVING A ROTATABLE ELEMENT AND ADAPTED TO PRODUCE AN OUTPUT ELECTRIC CURRENT WHICH VARIES IN ITS CHARACTERISTICS WITH VARIATION IN THE ANGULAR POSITION OF ITS ROTATABLE ELEMENT; MEANS DRIVINGLY CONNECTING THE ROTATABLE ELEMENT OF ONE OF SAID ELECTRICAL INSTRUMENTALITIES WITH THE MONITOR ROLLER; MEANS DRIVINGLY CONNECTING THE ROTATABLE ELEMENT OF THE OTHER ELECTRICAL INSTRUMENTALITY WITH THE VARIABLE SPEED DRIVE MEANS; OUTPUT PRODUCING MEANS, COMPRISING MEANS ELECTRICALLY CONNECTING SAID TWO ELECTRICAL INSTRUMENTALITIES, FOR PRODUCING A CONTROL OUTPUT ELECTRIC CURRENT WHICH HAS CHARACTERISTICS THAT VARY WITH CHANGES IN THE RELATIVE ANGULAR POSITIONS OF THE ROTATABLE ELEMENTS OF SAID TWO ELECTRICAL INSTRUMENTALITIES; AND SERVO MEANS ELECTRICALLY CONNECTED WITH SAID OUTPUT PRODUCING MEANS, TO BE RESPONSIVE TO THE OUTPUT THEREOF, AND DRIVINGLY CONNECTED WITH THE SPEED CONTROL ELEMENT OF THE VARIABLE SPEED DRIVE MEANS TO EFFECT CORRECTIONS IN THE SPEED OF THE IMPRESSION ROLLER IN ACCORDANCE WITH CHANGES IN THE ANGULAR RELATIONSHIP BETWEEN THE MONITOR AND IMPRESSION ROLLERS.