SCHEMATIC FOR AN OPTOELECTRONIC KEY LOCK BY JOE SCHARF * DENOTES A CONNECTED WIRE OR A FOOTNOTE _______________________________________________________________________________ o------*------------------------------------------------------------------+ | +-----*---*---*---*-----------*----------------*----*----- | | --- --- | | | | | | | | ^ ^ |+ | | | R5> | | * | T1 |D1-D4|C1--- > > | R4 10K> Q2 | | )||(---* | ^^^ > > +---^^^-*----+ > E/ )|| )||( | | | R1> R2> | | *--[B )|| )||(---|-----* | | | | | R6> C\ )|| | | | | | *-----+ | | > | | | --- --- | | | | | | > | | | ^ ^ | | +---+ | | PC3v C/ | +---+ | | | | v C/ | | --- [B | *-----+ 115V | | | | ---PC1 [B | Q1 C/ | E\ o o | 60 Hz | +-----*---* | E\--|--+ +--*---[B | | |SSR| R7> | | v C/ | | | E\ PC4v C/ o --- > | | ---PC2 [B | |R3> | --- [B | --- > | | | E\--*--+ > | | E\ o | C2 | | | | > | | | | o --- | | | | |PC5v C/ | | --- | | | | | --- [B | | | | | | | | | E\ | | | | | | | | | | *-----+ | | | | | | | | | | | | | | | | | | | +---*------------------*-----*---*--------*---+ | | | o-----+--------------------------------------------------------------------+ _______________________________________________________________________________ PARTS LIST T1: 115 TO 6.3V,.6A:STANCOR P-6465 OR TRIAD F-13X D1-D4: 1N4000 OR SIMILAR C1: 500 uF/10V ELECTROLYTIC C2: .05 uF/200V SSR (Solid State Relay): CRYDOM D1202 OR EQUIVALENT R1,R4: 120 OHM,.50W R3,R5: 10K,.50W R2,R6: 6.8K,.50W R7: 470 OHM, .50W Q1: 2N5172 OR ANY GENERAL PURPOSE NPN Q2: 2N5354 OR ANY GENERAL PURPOSE PNP PHOTOCOUPLERS: (PC):GE H13A1 OR EQUIVALENT SOLENOID: ANY 120V UNIT UP YO 1A COIL CURRENT SUCH AS GUARDIAN 2HD-120VAC FOOTNOTE--- * - SOLENOID - JUST MAKING SURE YOU KNOW WHAT THIS PART IS. NOTE: THE NUMBER OF PHOTOCOUPLERS CAN BE FROM TWO TO SIX. SEE BELOW. _______________________________________________________________________________ THIS PROJECT USES A SOLID STATE RELAY TO DRIVE A SOLENOID. IT IS CONTROLLED BY A PHOTOCOUPLER TRANSISTOR CIRCUIT. THE PHOTOCOUPLERS (PC'S) USED ARE OF INERRUPTER TYPE. HEY HAVE A .12 BY .30-INCH SLOT BETWEEN LED EMITTER AND TRANSISTOR DETECTOR. WHEN THE SLOT IS EMPTY OR FILLED WITH AN INFRARED TRANSMISSIVE MATERIAL, THE PHOTOTRANSISTOR WILL CONDUCT CURRENT IN RESPONSE TO THE LIGHT OF THE LED. IF THE SLOT IS FILLED WITH AN OPAQUE, THE TRANSISITOR WILL REMAIN OFF. THE ENTIRE SLOT IS NOT SENSITIVE. THE SENSITIVE PART IS ONLY A SMALL SIXTY-MIL AREA WITHIN THE GAP. IF AN OBJECT IS PLACED IN THE SLOT WITH A SIXTY-MIL HOLE IN THE CORRECT LOCATION, THE LED LIGHT WILL GET THROUGH TO THE TRANSISTOR. THE KEY LOCK USES AN ARRAY OF THESE INTERRUPTER PC'S WHICH ARE MIXED SO THAT ONLY THE CORRECT "LIGHT COMBINATION" WILL OPEN THE LOCK. WITH 4 PC'S THERE ARE 16 COMBINATIONS 5 GIVES 32 AND SO ON. THE CIRCUIT AS SHOWN CONTAINS 5 PC'S THE CIRCUIT WITHOUT CHANGING RESISTOR VALUES CAN ACCOMODATE FROM FOUR TO SIX PC'S WITH TWO OR THREE USED THE OPEN (NO LIGHT AS IN PC1 AND PC2) OR THE CLOSED MODE (LIGHT ON THE TRANSISTOR DETECTOR AS IN PC3-PC5) TO EXPAND THE OPEN TO FOUR COUPLERS R1 SHOULD BE REDUCED TO 82 OHMS AND ALL FOUR EMITTERS CONNECTED IN SERIES AND THE DETECTORS IN PARALLEL. TO EXPAND THE CLOSED COUPLERS TO FOUR, R4 MUST BE REDUCED TO 82 OHMS AND R2 AND R6 TO 5.6K TO ASSEMBLE THE ARRAY THE COUPLERS SHOULD BE CAREFULLY GLUED TOGETHER A SMALL AMOUNT OF EPOXY OR ONE OF THE SUPER GLUES ON ADJACENT SIDES WILL HOLD THIS ARRAY ANY EXCESS PLASTIC SHOULD BE TRIMMED WITH A SMALL BLADE TO INSURE THAT THE CENTERS ARE AT CONSTANT SPACINGS ALSO THE SLOTS MUST BE KEPT IN LINE ALONG BOTH THE TOPS AND SIDES OR PROBLAMS WILL RESULT LATER ON CARE MUST BE TAKES THAT NO GLUE GETS IN THE SLOTS ON THE DETECTORS OR EMITTERS. A SMALL PIECE OF PLASTIC OR METAL IS GLUED ON ONE ENDTO ACT AS A STOP FOR THE KEY, AND A COVER IS GLUED TO THE TOP OF THE SOUPLERS. THIS FORMS A TUNNEL OR KEYWAY. THE KEY CAN BE BUILT OUT OF PLASTIC OR METAL. THE LENGTH IS DETERMINED BY THE NUMBERS OF PC'S USED IN THE LOCK. ALLOW ONE-QUARTER INCH OF THE ENTIRE FOR EACH PC PLUS TWO INCHES FOR A HANDLE. IF THE KEY IS CUT PRECISELY, IT WILL SLIDE INTO THE TUNNEL WITHOUT MUCH UP AND DOWN PLAY. AT THIS POINT THE COMBINATION IS DETERMINED. DRILL A 1/16-INCH DIAMETER HOLE (ONLY AT THE CENTERS CORRESPONDING TO THE PC'S USED IN THE CLOSED MODE) THE HOLE PLACEMENT MUST BE ACCURATE. IF YOU DO NOT HAVE THE PROPER TOOLS TO ACCURATELY LOCATE THE HOLES, USE A LARGER DRILL BIT TO INSURE THAT THE LIGHT PATH IS CLEAR. THE ELECTRONICS CAN BE ASSEMBLED WITHIN A 4X5X6-INCH BOX THE PHOTOCOUPLER ARRAY CAN BE MOUNTED ON A PREFORATED CIRCUIT BOARD USING SEVERAL OF THE HOLES ON THE PC'S THE OPEN END OF THE PC TUNNEL SHOULD BE PLACED AT THE EDGE OF THE BOX WITH A HOLE LARGE ENOUGH FOR THE KEYTO ENTER THE TUNNEL. WHEN MAKING THE PC DISPLAY, MAKE SURE THAT THE CONNECTORS OF OF THE NORMALLY OPEN AND NORMALLY CLOSED COUPLERS ARE NOT INTERCHANGED ONCE THE UNIT IS ASSEMBLED, INSERTING THE KEY SHOULD ENERGISE THE SOLENOID IF NOT CHECK THE COLLECTOR VOLTAGE OF Q1. _______________________________________________________________________________ WELL, THIS IS IT I GOT IT OUT OF A BOOK CALLED OPTOELECTRONICS GUIDEBOOK IF YOU HAVE ANY QUESTIONS LEAVE E-MAIL ON CHUCKS PLACE (304-776-7078) TO JOE SCHARF HOPE YOU ENJOY THIS AND IF YOU HAVE ANY UPLOAD THEM TO THE BOARD. _______________________________________________________________________________