Patent GB-963586-A (GB)
Title: A method of and a device for testing material
Inventor: PATZER WILLIAM A
IPC: G01N21/956
Filed: 1960-09-22
Abstract: 963,586. Photo-electric testing of printed sheets. AUTOMATIC CANTEEN CO. OF AMERICA. Sept. 2, 1960, No. 32657/60. Heading G1A. A thin printed sheet, e.g. a currency note, having predetermined portions more transparent to light than other predetermined portions is tested by (1) placing the sheet between a light source and two arrays of light responsive cells located to correspond with said first and second predetermined portions of the sheet and (2) indicating when both (a) the intensity of the light transmitted through the more transparent portions is within predetermined acceptable upper and lower limits and (b) the intensity of the light transmitted through the less transparent portions is less than a predetermined acceptable limit. The invention may be applied to detecting counterfeit currency notes, cheques, tickets &c. and is described as applied to apparatus which tests a manually inserted currency note, automatically accepts the note if it is genuine and issues coins as change. As shown in plan view in Fig. 2 and in vertical sections in Figs. 4 and 5, the note 20 is placed in a rectangular recess 22 in a slide 24 and held therein by a hinged flap 36, the slide 24 and flap 36 having aligned apertures 38 and 64 so that when the slide is pushed into the test position shown by broken lines in Fig. 2 light from incandescent electric lamps 32 can pass through the note and the apertures 38 to photo-electric cells 34. As shown in Fig. 7 the cells 34 are arranged in three groups 34b, 34g and 34w arranged respectively under portions b of the note 20 printed with black ink, portions g printed with green ink and blank portions w, the portions w being more transparent than the portions b and g. The outputs from the cells 34b and 34g are applied directly to respective relays B and G whose contacts 342 and 345 are connected in parallel to a first control relay 204 having a pair of normally closed contacts 206, 208 which will remain closed unless light transmission through the portions b and g exceeds the acceptable limit. The outputs from the cells 34w are applied to a relay W, (1) through a variable resistor 198 and the right-hand contacts 200 of a switch relay 192 or (2) directly via the left-hand contact of the contacts 200. In the first case the contact 348 of the relay W is connected to the first control relay 204 via the right-hand contact of contacts 194 of the switch relay 192 so that the contacts 206, 208 of the first control relay 204 will open only if light transmission through the more transparent portions w of the note 20 exceeds the predetermined upper limit as determined by the setting of the resistor 198; in the second case the contact 348 of the relay W is connected via the left-hand contact of contacts 194 to a second control relay 210 having a pair of normally open contacts 212,214 which will be closed only if the light transmission through the portionw of the note 20 exceeds the predetermined lower limit. Holding contacts 207, 213 are provided for the control relays 204, 210 to lock them in an energized state. As described below acceptance of the note 20 is conditional upon all the contacts 206, 208, 212 and 214 being closed. The slide 20 is held in the test position against the action of springs 48, Fig. 2, by a latch 42 rendered operative by a latching solenoid 158, Fig. 7, which is energized through normally closed switch and relay contacts 130, 144, 148, 152 and through the left-hand contacts of switches 114, 116 which are actuated by mechanical feelers 118, Figs. 2 and 5, which engage the leading edge of the note 20 if the note has the correct dimensions. The switch 130 is in the position shown only if the change giving mechanism C, Fig. 7, contains an adequate supply of coins; if not the latching solenoid cannot be energized and a warning lamp 134 lights up. If the latch 42 engages the slide 24 it closes a switch 162 to energize a starting relay 168 to close contacts 170 thereby energizing a timing motor 174 which rotates the rotor arm, 176, Fig. 1 (not shown), of a timing switch 220 to initiate a cycle of operations. As shown the switch 220 comprises an inner annular strip 178 making continuous contact with the rotor arm and outer arcuate strips 182-190 which are sequentially connected to the strip 178 by the rotor arm as it rotates. The transparency tests described above are effected during the first phase of the cycle during which the switch rotor contacts the arcuate strip 182 to energize the lamps 32, the switch relay 192 being energized to change over the contacts 194 and 200 associated with the relay W during the second half of this phase when the switch rotor also contacts the arcuate strip 184. During the next phase the switch rotor contacts the arcuate strip 186 and provided the contacts 208 and 214 of the control relays 204, 210 are both closed (i.e. the note 20 has passed the acceptance test) this energizes a "stripper" motor 102 to (1) rotate spaced pairs of rollers 96, 98, Fig. 5, and Figs. 3 and 6 (not shown), mounted beneath the test position of the slide 24 and (2) close a "stripper" switch 218, Fig. 7, to energize a "stripper" solenoid 74, Figs. 4 and 7, which causes a vertical guillotine plate 72, Fig. 4, to move vertically downwards through the elongated slot 64 in the flap 36 and corresponding slots in the slide 24 and the table top 30 supporting the slide 24 thereby folding the note 20 and feeding it between the rotating rollers 96, 98 which complete the removal of the note. The passage of the folded note 20 between the rollers 96, 98 actuates a rod 110, Fig. 5, to close a switch 112, Fig. 7, to energize the change dispensing motor 228 via the still closed contacts 206, 212 of the control relays 204, 210, the right-hand contacts of switches 114, 116 which were restored to their original condition as shown in Fig. 7, when the note 20 was removed from the slide 24 and the left-hand contact of contacts 148 of a relay 147 which was energized through contacts 215 of the relay W when the latter relay was energized. When the rotor arm 176 of the switch 220 moves from the arcuate strip 186 to the arcuate strips 188 and 190 for the final reset phase, the stripper motor 102 (and thence the stripper solenoid 74 and change dispensing motor 228) are deenergized and a reset relay 224 is energized to open its contacts 225 thereby de-energizing the latching solenoid 158 and so releasing the slide 24 for return to its initial position. Since this last operation also de-energizes the starting relay 168 thereby interrupting the power supply to the timing motor 174 via contacts 170, an alternative power supply, is provided via the arcuate strip 190 of the switch 220. If the note 20 does not pass the acceptance test it will remain in the slide 24 when the latter is returned to its initial position.