| 摘要 |
A taximeter with logic circuitry that provides passenger detection, distance measuring, clock timing, speed referencing, tamper and fault detectors, manual pushbutton controls, settable constants for distance, time and money, and an emergency power supply. Further logic circuitry is provided to count passengers, calculate and add extras, control calibration externally, condition distance pulses, scan tamper and fault detectors, synchronize and debounce manual pushbutton controls, store and input constants, disable the taximeter, enter an external reset code, and internally compare the reset code. Additional logic circuitry may be provided to control the fare charging clock, perform program arithmetic, perform accumulator functions and control logic operations. Also, additional logic circuitry provides an extras charged display, a fare display, rate of charge display panels, recording counters and control of the taxi toplight. All of the logic circuitry is interconnected to provide a taximeter that accurately computes and displays taxi fares, adds extras charges manually or automatically, displays extras charged on the meter face, detects tampering and circuit faults automatically, displays a tamper number on the meter fare display that indicates the specific tamper or fault, displays meter operation on the taxi toplight, including tampering, disables the taximeter from operation in the event of a tamper or fault, can be reset to normal operation only by an external coded reset device, counts and displays taxi driveshaft rotations on the fare display under the command of an external calibration device, uses two or more selectable charge rates, has rate of charge display panels on the meter face that indicate the rates available to a customer before a meter start and the rate in use when the meter is on, disallows switching from one rate to another on any given trip, synchronizes manual control operations to prevent errors, disables the manual controls at a predetermined minimum speed to prevent mischievous or accidental meter operation, automatically restarts clock charging at minimum speed, disables manual extras the first time the taxi reaches minimum speed, provides a method of accurately calibrating the distance charging sector of the taximeter without any parts or special skills, totals all fare charges on one fare display, performs retroactive charging for any distance traveled by a customer before the meter is started, prevents highflagging by starting itself automatically and accurately whenever a customer is in the taxi and provides positive notice to the taxi owner in the event of any tampering to the taximeter system.
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