GB929412A - Thrust transmitting device - Google Patents

Abstract

929,412. Punching-machines. SVENSKA DATAREGISTER A.B. Sept. 4, 1959 [Sept. 9, 1958], No. 30305/59. Class 31 (2). [Also in Group XXIV] Thrust-transmitting linkwork, which may be used in a punch, comprises a tubular member 22, containing a movably-mounted magnetic element 28, telescopically engaging a tubular member 24 containing a fixedly mounted magnetic element 30, the polarity of the magnetic elements 28, 30 being controlled by coils 36, 38, respectively, so that when dissimilar poles of the magnetic element abut, Fig. 3, the assembly is capable of transmitting force, but when the polarity of one end of elements is reversed, so that like poles are adjacent, the element 28 is deflected relative to the element 30, Fig. 2, so that the tubular members 22, 24 can move relative to one another and the assembly cannot transmit a thrust. One magnetic element may be a permanent magnet enabling one coil to be dispensed with or both elements may be permanent magnets and a coil is used to remagnetize one of the magnets to the desired polarity. No further signals are then required until it is desired to change the mode of operation of the device. The fixed magnetic element may be stepped, Figs. 4-6, not shown. As applied to punching apparatus, Fig. 10, a number of the above devices form punch elements 102 above which a tape or card 104 is indexed by a roller 138 below a die-plate 106 having holes 108 which correspond to the punch elements 102, and between indexing operations the die-plate assembly is moved axially of the punch elements 102 by cams 126, 128 and, depending on whether or not the punch elements are set to resist force, a hole is or is not punched in the card or tape. The control signal data may be entered from a keyboard 118 or a record 116 and sensing head 114.