Patent GB-1166189-A (GB)
Title: Subscription Television Receiver
IPC: H04N7/16
Filed: 1967-07-12
Abstract: 1,166,189. Selective punching apparatus. ZENITH RADIO CORP. 12 July, 1967 [28 July, 1966], No. 32178/67. Heading B4B. [Also in Divisions E2, F2, H1 and H3] In a subscription television receiver (see Division H3) a card is punched in a position which represents a particular programme that has been viewed, the punching mechanism being set to particular x and y co-ordinates as a result of adjustment of switches to receive that programme. The first switch 94 (Fig. 4) rotates gears 159 which mesh with a sector 155 (Fig. 5) to move vertically a die block 157 and guideplate 156, thus establishing the y-co-ordinate of the hole to be punched in a card 96. In operation, switch 93 (Fig. 4) is placed in its TV position thereby rotating shaft 106 (Fig. 5) and turning crank 125 so that a ball 142 drops into a notch 125b and permits a cover 141 to be moved to the right so that a card 96 can be inserted. The cover is then closed and switch 94 (together with switch 95, see below) adjusted in accordance with the programme to be received. Switch 93 is then put into its PV position, thereby locking switches 94, 95 and moving a link 128 having parallel legs 128a pivoting on a pin 126 in the crank 125. The link is moved from the dotted position to the position shown, and a hinge pin 131 on the other end moves two pairs of hinge members 132, 133 (only one pair shown). The members 133 are pivoted to a fixed point at 136 so that the free ends of members 132 drive a unit 117, 118 to the left along rods 116 against a spring (not shown). This unit carries two pilot pins which enter holes in the card 96 and also eleven sensing pins which pierce the card and engage pieces of aluminium foil in pleats at the bottom of the card. This action establishes a predetermined pattern of conductive paths between the eleven sensing pins which is distinctive for the 96 programmes represented by the particular card used. The second switch 95 (Fig. 4) rotates a crown wheel 163 which through an idler gear 164 turns a gear 167 loosely mounted on a hollow spindle 168. The gear 167 is divided into twelve angular segments of which eleven have holes and one is solid (Fig. 6, not shown). When the receiver is correctly set up, current flows through the heater of a bimetallic strip 72 and the free end pushes a release pin 178 to the left allowing a ball 175 to drop into a narrowed part of this pin. The spindle 168 is now no longer locked to sleeve 174 and a spring 183 drives gear 167 to the left. Twelve flexible wires A-M are arranged around the axis of spindle 168, and when the gear 167 moves to the left eleven of these wires will pass through holes in the gear 167 but the end of one will strike the twelfth solid portion. This wire will thus be driven to the left and the other end will pass through the guide-plate 156 and punch a hole in the card 96. The x-co-ordinate of the hole will depend on which of the twelve wires has been operated, and this will depend on the angular position of gear 167 and switch 95. When switch 93 is put back into its TV position before receiving another programme a cam 185 (attached to hinge 133) engages the left hand end of spindle 168 and drives it to the right. A pin 181 then moves a sleeve 148 to engage an enlarged portion 151 of the wire that was previously operated and moves the wire out of the card 96 until a stop 152 touches the support 100c. The pin 178 is also moved to the right by spring 182. The ball 175 now enters a chamfered portion (174a in Fig. 5a, not shown) in a recess in the sleeve thereby locking spindle 168 against movement to the left until again operated by the bimetallic strip 72. Movement of the spindle 178 and gear 167 to the right closes contacts 71 which complete a circuit to the heater of the strip 72 ready for the next operation. If fraudulent operation is attempted by putting a metal plate beside the card 96 to prevent punching of the latter, the gear 167 will move only partly to the left and its lower edge will engage an arm 61 to open contacts 62 and disable the receiver.