Electronic prepayment type electric watt-hour meter

摘要

AN ELECTRONIC PREPAYMENT TYPE ELECTRIC WATT-HOUR METER WHICH IS CAPABLE OF PREVENTING A MONETARY LOSS DUE TO A TIMING DIFFERENCE BETWEEN AN ELECTRIC POWER SUPPLY TIMING AND AN ELECTRIC POWER PAYMENT TIMING, WHICH INCLUDES AN ELECTRONIC PREPAYMENT TYPE WATT-HOUR METER HAVING POWER CONVERTER MEAN (10) FOR CONVERTING A HIGH VOLTAGE AND CURRENT SUPPLIED FROM A POWER SOURCE INTO A LOW VOLTAGE AND CURRENT; ELECTRIC POWER/FREQUENCY CONVERTER MEANS (30) FOR PROVIDING AN INDICATION OF ELECTRIC POWER USAGE BY MULTIPLYING AN OUTPUT VOLTAGE AND CURRENT FROM THE POWER CONVERTER MEANS (10) AND FOR OUTPUTTING A SIGNAL HAVING A FREQUENCY PROPORTIONAL TO THE MULTIPLIED RESULT; AN ELECTRIC POWER BILLING COMPUTATION AND DISPLAY UNIT (50) FOR DIVIDING AND ACCUMULATING THE FREQUENCY OF THE SIGNAL OUTPUTTED FROM THE ELECTRIC POWER/FREQUENCY CONVERTER MEANS (30) AT A PREDETERMINED TIME INTERVAL, COMPUTING THERE FROM THE AMOUNT OF ELECTRIC POWER USED AND A BILLING AMOUNT THERE FOR, COMPARING THE THUSLY COMPUTED BILLING WITH A PREVIOUSLY SET PREPAYMENT AMOUNT, AND GENERATING A LOAD BLOCKING SIGNAL WHEN THE BILLING AMOUNT EQUALS THE PREPAYMENT AMOUNT, WHEREIN SAID ELECTRIC POWER BILLING COMPUTATION AND DISPLAY UNIT (50) INCLUDES: A DIVIDER MEANS (51) FOR DIVIDING AND ACCUMULATING THE FREQUENCY SIGNAL OUTPUTTED FROM THE ELECTRIC POWER/FREQUENCY CONVERTER MEANS (30) AND FOR COMPUTING THE AMOUNT OF ELECTRIC POWER USED IN ACCORDANCE THEREWITH; RATES SETTING AND INPUT UNIT (52) FOR SETTING A BASIC RATES FOR ELECTRIC POWER SERVICE AND RATES FOR ELECTRIC POWER USAGE, AND FOR INPUTTING THE PREPAYMENT AMOUNT, AND SETTING "SEASON CHANGE DAY" IN ORDER TO PREVENT A MORE OR LESS EXPENSIVE ELECTRIC POWER BILLING FROM BEING COMPUTED AND DETERMINE THE PAYMENT PERIOD OF THE ELECTRIC POWER RATES; A COMPARING UNIT (53) FOR COMPUTING THE BILLING AMOUNT BASED ON THE AMOUNT OF ELECTRIC POWER USED FROM THE DIVIDER MEANS (51) AND THE BASIC RATE AND USAGE RATES FROM THE RATES SETTING AND INPUT UNIT (52) AND FOR COMPARING THE THUSLY COMPUTED BILLING AMOUNT WITH THE PREPAYMENT AMOUNT FROM THE RATES SETTING AND INPUT UNIT (52) AND FOR OUTPUTTING A COMPARISON SIGNAL IN ACCORDANCE THEREWITH; A LOAD CONTROLLER (54) FOR CONTROLLING THE POWER SUPPLIED TO A CIRCUIT LOAD IN ACCORDANCE WITH THE COMPARISON SIGNAL FROM THE COMPARING UNIT (53); AN ALARM SIGNAL OUTPUT UNIT (55) FOR CONTROLLING AN ALARM OCCURRENCE IN ACCORDANCE WITH THE COMPARISON SIGNAL FROM THE COMPARING UNIT (53); A DISPLAY UNIT (56) FOR DISPLAYING THE AMOUNT OF THE ELECTRIC POWER USED AND THE BILLING AMOUNT THERE FOR IN ACCORDANCE WITH THE COMPARISON SIGNAL OF THE COMPARING UNIT (53); A SWITCH MEANS (60) FOR DISCONNECTING A LOAD FROM THE POWER SOURCE UNDER THE CONTROL OF THE LOAD BLOCKING SIGNAL FROM ELECTRIC POWER BILLING COMPUTATION AND DISPLAY MEANS (50), CHARACTERIZED IN THAT, SAID ELECTRIC POWER RATES SETTING AND INPUT UNIT (52) FURTHER COMPRISES A BAR CODE SCANNER MEANS FOR INPUTTING THE PREPAYMENT AMOUNT BY READING INFORMATION OF A BAR CODE. (FIG 2)