Controlling recording devices

Claim 1

IN A RECORDING DEVICE, A PRESSURE SENSITIVE RECORDING STRIP, MEANS FOR MOVING SAID STRIP ALONG A PREDETERMINED PATH; SAID PATH INCLUDING A CURVED PORTION; PERCUSSION MEANS ARRANGED FACING SAID STRIP ON THE CONCAVE SIDE OF SAID CURVED PORTION; SAID PERCUSSION MEANS HAVING A LOWER EDGE FORMING A ROTARY AXIS EXTENDING ACROSS SAID PATH, AND ANOTHER PARALLEL UPPER EDGE ROTATABLE ABOUT SAID AXIS SO AS TO MOVE SAID PERCUSSION MEANS TO AND FRO WITH RESPECT TO SAID STRIP; A GALVANOMETER NEEDLE ARRANGED BETWEEN SAID STRIP AND SAID PERCUSSION MEANS SO AS TO MOVE SUBSTANTIALLY IN A PLANE TANGENTIAL WITH RESPECT TO SAID CURVED STRIP PORTION, MEANS FORMING AN EXTENSION OF SAID PERCUSSION MEANS AT SAID ROTARY EDGE ON ONE SIDE THEREOF FORMING A LEVER TO CAUSE SAID PERCUSSION MEANS TO PRESS ITS UPPER EDGE TO AND FROM SAID STRIP THEREBY CAUSING SAID NEEDLE SELECTIVELY AND MOMENTARILY TO PRESS OR NOT TO PRESS AGAINST SAID STRIP, AND TO PRODUCE OR NOT PRODUCE A VISIBLE POINT SHAPED MARK ON SAID STRIP; AND MEANS ARRANGED ON THE OTHER SIDE OF SAID PERCUSSION MEANS SELECTIVELY TO HOLD SAID PERCUSSION MEANS IN A FIXED POSITION OUT OF ENGAGEMENT WITH SAID STRIP; SAID HOLDING MEANS INCLUDING A FLAT LEAF SPRING ATTACHED TO SAID DOOR BELOW THE LOWER EDGE OF SAID PERCUSSION MEANS, AND ARRANGED TO PRESS IN ITS OPERATIVE POSITION AGAINST THE BACK OF SAID PERCUSSION MEANS THEREBY PRESSING SAID PERCUSSION MEANS