Printer having type drum with blank area and hammer on movable carriage

Claim 1

A HIGH SPEED SERIAL PRINTING DEVICE FOR OFFICE MACHINES AND DATA PROCESSING EQUIPMENTS, HAVING A TYPE DRUM, MEANS FOR ROTATABLY SUPPORTING SAID DRUM IN AN AXIALLY FIXED POSITION, A PLURALITY OF PARALLEL ROWS OF TYPES, EACH ONE OF SAID ROWS BEING ARRANGED CIRCUMFERENTIALLY ON SAID DRUM, AT LEAST TWO ROWS OF TYPES BEING SIMILAR AND AXIALLY DISTANCED ACCORDING TO THE HORIZONTAL PRINTING SPACING, AND COMPRISING IN COMBINATION: (A) AN ANGULAR PORTION ON SAID DRUM DEPRIVED OF TYPES, EACH ONE OF SAID ROWS BEING ARRANGED SUBSTANTIALLY IN AN ANNULAR PORTION OF SAID DRUM EQUAL TO 180 DEGREES, (B) A CARRIAGE TRANSVERSELY MOVABLE PARALLEL TO SAID DRUM, (C) MEANS FOR CONTINUOUSLY ROTATING SAID DRUM, (D) A SINGLE HAMMER OPERABLE FOR ENGAGING A SELECTED TYPE OF SAID DRUM TO EFFECT A FLYING PRINTING THEREOF DURING THE ROTATIVE MOTION OF SAID DRUM, (E) MEANS FOR MOUNTING SAID HAMMER ON SAID CARRIAGE, SAID HAMMER AND SAID CARRIAGE TRANSVERSELY MOVING DURING PRINTING HAMMER OPERATION, (F) MEANS FOR CONTINUOUSLY MOVING SAID CARIAGE ALONG A PRINTING LINE AT SUCH A CONSTANT SPEED AS TO COVER ONE HORIZONTAL PRINTING SPACING DURING EACH REVOLUTION OF SAID DRUM, (G) SAID HAMMER HAVING A TRANSVERSE DIMENSION EQUAL TO SAID HORIZONTAL SPACING, WHEREBY ANY TYPE OF A PREDETERMINED ROW OF SAID PLURALITY MAY BE FULLY ENGAGED BY SAID HAMMER DESPITE ITS TRANSVERSE MOVEMENT, (H) AND AN ELECTROMAGNET MOUNTED ON SAID CARRIAGE AND ADAPTED TO OPERATE SAID HAMMER WHEN SAID SELECTED TYPE CROSSES SAID PRINTING LINE, SAID ELECTROMAGNET BEING DEENERGIZED WHEN SAID PORTION DEPRIVED OF TYPES CROSSES SAID PRINTING LINE.