Adjustable biasing device for the keys of a business machine

Claim 1

IN A KEYBOARD OPERATED MACHINE INCLUDING A TOUCH ADJUSTMENT ARRANGEMENT, IN COMBINATION, A SUPPORTING FRAME: A PLURALITY OF KEYS LEVERS MOUNTED PIVOTALLY AND PARALLEL TO EACH OTHER ON SAID SUPPORTING FRAME; A MOVABLE ELONGATED TOUCH CONTROL MEMBER ENGAGING ALL SAID KEY LEVERS SPACED FROM THE POINTS AT WHICH THEY ARE PIVOTED TO SAID SUPPORTING FRAME; ATTACHING MEANS SECURED TO SAID MOVABLE TOUCH CONTROL MEMBER; AN ADJUSTING MEMBER MOUNTED ON SAID SUPPORTING FRAME FOR TURNING MOVEMENT ABOUT AN AXIS, SAID ADJUSTING MEMBER HAVING A PLURALITY OF HOLDING PORTIONS SPACED DIFFERENT RADIAL DISTANCES FROM SAID AXIS AND BEING TURNABLE ABOUT SAID AXIS INTO A PLURALITY OF ADJUSTED POSITIONS IN WHICH DIFFERENT HOLDING PORTIONS ARE LOCATED ON A STRAIGHT LINE CONNECTING SAID AXIS WITH SAID ATTACHING MEANS; AND TENSION SPRING MEANS FOR PULLING SAID MOVABLE ELONGATED TOUCH CONTROL MEMBER TOWARD SAID ADJUSTING MEMBER, SAID TENSION SPRING MEANS HAVING ONE END SECURED TO SAID ATTACHING MEANS AND THE OTHER END THEREOF ENGAGING THE HOLDING PORTION WHICH IS LOCATED ON SAID LINE, WHEREBY IN DIFFERENT ADJUSTED POSITIONS OF SAID ADJUSTING MEMBER THE DISTANCE BETWEEN THE ENDS OF SAID TENSION SPRING MEANS AND THEREBY THE FORCE OF TENSION SPRING MEANS PULLING SAID MOVABLE ELONGATED TOUCH CONTROL MEMBER TOWARD SAID ADJUSTING MEANS IS VARIED WHILE NO TURNING MOMENT IS EXERTED ON SAID ADJUSTING MEMBER BY SAID TENSION SPRING MEANS.