GB778570A - Keyboard-operated tape-perforating apparatus - Google Patents

Abstract

778,570. Type-making machines. TELETYPESETTER CORPORATION. March 6, 1956 [June 21, 1955], No. 6995/56. Class 100(3) Strip-perforating machines. In a keyboard-controlled tape-perforating apparatus in which selected punches of a tapeperforating device for producing code combinations of perforations in a record tape, such as may be used for automatically controlling the operation of a type linecasting and composing machine, are actuated by means of a cam which is set in rotation to actuate the selected punches through the intermediary of a clutch comprising a driving member (85) which is continuously urged to rotate, but is normally held in a stationary position, to prevent the cam from being rotated by the clutch, by means of a blocking lever (87) in rotation-blocking engagement with the driving member, but which is withdrawable from the driving member, to permit the cam to be rotated by the clutch under the control of a clutch trip-off member (64) which is actuated to free the blocking lever from the driving member when any one of the keys is depressed, the trip-off member is adapted' when actuated to close a contact (57) for completing an operating circuit of an electromagnet (28), whereby the electromagnet is energized to attract anarmature member (26) which functions to unlatch from the blocking lever a latching member (89) normally holding the blocking lever in engagement with the driving member, so enabling the blocking lever to be withdrawn by the action of a spring (91). Current from a D.C. source 47, or an A.C. source rectified by a rectifier 31, builds up a charge on a capacitor 46. When the trip-off member 64 moves a conductor 36 against a conductor 34 to close the contact 57, current passes through a contact 56 to the electromagnet 28, which is actuated by the initial surge from the capacitor 46. The armature member 26 rotates the latching member 89 to release the blocking lever 87 and to actuate a plunger 47<SP>1</SP> to open the contact 56 to put a resistor 44 in the circuit and reduce the current to an amount sufficient to hold the armature member 26 in actuated position, while an extension 52 of the member 89 rocks a differential lever 48 so as to allow the conductor 34 to move downwards far enough to prevent vibrations owing to too light contact with the conductor 36, while leaving a gap between the conductor 34 and the lever 48. The member 89 also rotates a non-repeat lever 92 clockwise. When the member 85 rotates, it acts on a cam roller 23 to return the lever 87 to blocking position where after half a revolution of the member 85, it engages the other of two extensions 82, 83 of the member 85 to stop the latter, the blocking lever 87 being locked in blocking position by the member 89, or, if the magnet is still energized, 'by a shoulder 97 of the lever 92. The return movement of the member 89 on release of the key closes the contact 56 and restores the lever 48, the contact 57 being opened only after the gap between the conductor 34 and the lever 48 has been closed. Specification 420,084 is referred to.