Fuel-dispensing system with self-checking means

• US 4,290,538 A
• Filed: 01/18/1979
• Issued: 09/22/1981
• Est. Priority Date: 10/15/1975
• Status: Expired due to Term

• Current Assignee: Dresser Europe SA
• Original Assignee: Dresser Europe SA
• Inventors: White, Roy L., Leevers, David F. A., Kitchin, Peter W.
• Primary Examiner(s): Spar, Robert J.
• Assistant Examiner(s): WACYRA, EDWARD MICHAEL
• Application Number:
  US06/004,316
• Time in Patent Office: 978 Days
• Field of Search: 222/23, 222/25-28, 222/32, 222/33, 222/36, 222/37, 222/40, 222/71, 222/76, 364/464, 364/465, 364/119, 364/737, 364/738, 235/61 M, 235/92 FL, 235/92 EC, 235/94 R, 235/94 A, 235/306, 307/64, 307/66, 340/146.1 AG, 340/606, 340/609, 340/610, 365/228, 365/229, 371/68
• US Class Current: 222/25
• CPC Class Codes: B67D 7/228 using digital counting
• CPC Class Codes: G06Q 50/06 Energy or water supply

Abstract

A processor is used to control a price display unit for a fluid-dispensing system. The amount of fluid dispensed by the system in measured and information responsive thereto is fed to the processor. The processor calculates the cost of the dispensed fluid and those costs are then displayed. The processor automatically cross-checks the validity of the displayed cost with the amount of fluid dispensed. A plurality of self-checking features insure proper system operation and also preserve signals stored in a memory if there is a power failure.

Claims

1. A self-contained fluid-dispensing machine comprising means for measuring a dispensed fluid, said measuring means generating signals responsive to a flow of fluid through said fluid-dispensing machine for measuring an amount of fluid as it is actually being dispensed;

said dispensing machine further including computer means having a processor interconnected with said measuring means for monitoring the operation of said machine, means responsive to said signals from said measuring means for feeding information to the computer means relative to said amount of fluid dispensed and measured by the measuring means;

means in the computer means for calculating the cost of the measured amount of dispensed fluid in accordance with a predetermined unit price;

means for visibly displaying the amount of said fluid dispensed and the corresponding cost thereof; and

self-checking means responsive to said computer means including means for continuously, positively and actively self-checking the validity of the said displays.

2. A self-contained fluid-dispensing machine comprising computer means including a processor, means responsive to a flow of fluid for measuring an amount of fluid dispensed, means responsive to said measuring means for feeding information to the computer means relative to said amount of fluid dispensed and measured by the measuring means, a plurality of single pole multi-way switch means, each of which is settable to a particular one of the multi-way positions to represent a particular digit of a unit price, the computer means including means for scanning the multi-way connections to all of the switches simultaneously, means in the computer means for calculating the cost of the measured amount of fluid in accordance with the unit price set by the positions of said multi-way switched means, means for visibly displaying the amount of said fluid which is dispensed and the calculated corresponding cost thereof, and means in the computer means for checking that only one signal is read from the single pole of each of said multi-way switches during a respective scan.

3. A self-contained fluid-dispensing machine comprising computer means including a processor within said machine;

means within said machine responsive to a flow of fluid through said machine for measuring an amount of fluid as it is being dispensed, means responsive to said fluid measuring means for feeding information to the computer means relative to said amount of fluid dispensed and measured by the measuring means;

means in the computer means for calculating the cost of the measured amount of fluid in accordance with a predetermined unit price;

means responsive to said fluid-measuring means for visibly displaying on said machine the amount of said fluid which is dispensed and the corresponding cost thereof; and

self-checking means entirely within said machine for operating said computer means in order to continuously, positively and actively check the display means, said display checking means including means for monitoring a signal applied within said machine in order to operate an element in the display means on said machine, means for comparing an output from the monitoring means with a parity signal from the computer means in order to verify the operation of said machine, and means for applying an output signal from the comparison means to the computer.

4. A machine as claimed in claim 3 including mechanically operated elements in the display means, a set coil and a reset coil for operating each of the elements, the monitoring means being arranged to detect the application of a signal to the set and the reset coil of each element.

5. A gasoline dispenser having self-contained therein both a fluid-dispensing machine and an electronic monitoring system for observing and checking the operation of said machine, said monitoring system comprising computer means including a processor, means responsive to a fluid flow through said machine for generating signals for measuring an amount of gasoline dispensed, means in the computer means responsive to said generated signals for independently calculating the cost of the measured amount of gasoline in accordance with a predetermined unit price, means for visibly displaying on said machine the amount of said gasoline dispensed and the corresponding cost thereof, means in the computer means responsive to said independent calculations for checking the accuracy of the visible display on said machine, power failure detector circuit means, the power failure detector circuit means comprising a half wave rectifier and a capacitor connected in series across a power supply source, a resistor network connected in series across a power supply source, a resistor network connected across the capacitor, and a Schmitt trigger circuit connected to an output obtained from the resistor network.

6. A dispenser as claimed in claim 5 including a totaliser shift register and means under the control of the power failure detector circuit to transfer information from the computer to the shift register upon the failure of power.

7. A gasoline dispenser having self-contained therein both a fluid-dispensing machine and a system for observing and checking the operation of said machine, said observing and checking system comprising computer means including a process, said dispenser including means responsive to a flow of fluid for measuring an amount of fluid dispensed, means responsive to said measuring means for feeding information to the computer means relative to said amount of fluid dispensed and measured by the measuring means, means in the computer means for independently calculating the cost of the measured amount of fluid in accordance with a predetermined unit price, means for visibly displaying on said machine the amount of said fluid dispensed and the corresponding cost thereof, means in the computer means responsive to said independent calculation for checking the visible display on said machine, and means for coupling an output from the computer means to a remote station, the coupling means including an emitter-follower connected transistor.

8. A self-checking, gasoline dispenser comprising means responsive to a flow of gasoline dispensed through said dispenser for generating electrical signals within said dispenser representing at least the volume of the dispensed gasoline, means for generating parity signals which accompany said gasoline dispensing caused signals, calculating means responsive to said electrical signals generated responsive to gasoline flow through said dispenser for calculating the cost of the dispensed gasoline in accordance with a predetermined unit price of the dispensed gasoline, means responsive to said calculating means for visibly displaying in association with the dispenser the calculated cost of the dispensed gasoline, said display means having a plurality of individually activated display elements, self-checking means responsive to said calculating means for continuously, positively and actively checking the operation of said display means in order to self-check the validity of said visible cost display as a function of the volume of gasoline actually dispensed, said self-checking means including monitoring means for detecting the application of a signal to each of the display elements, and parity check circuit means responsive to said parity signals and signals from the monitoring means for indicating the validity of the results given by the displays.

9. The dispenser of claim 8 wherein each of said display elements is a mechanically operated segment and a set coil and a reset coil for selectively operating each of the segments.

10. The dispenser of claim 8 wherein said self-checking means comprises means for storing in a memory circuit means a current total value of the dispensed gasoline and a current total volume of the gasoline dispensed, means for multiplying the current total volume of gasoline dispensed by said predetermined unit price, and means for comparing the results of said multiplication with the current total value of gasoline dispensed as said total value is stored in the memory circuit means and for shutting down the dispenser in the event that said comparing means finds a discrepancy.

11. The dispenser of claim 8 wherein the electrical signal generating means in said self-checking dispenser includes a pulse generator means having a rotating member which is turned by said flow of gasoline, said pulse generator means generating two sets of pulses which are in quadrature as the gasoline is dispensed, means for monitoring the two sets of pulses to detect whether or not the member is rotating correctly, and means for shutting down the system if said pulse monitoring means detects an incorrect operation of the rotating member.

12. The dispenser of claim 11 and means for comparing the number of pulses in the two sets of pulses and for shutting down the dispenser in the event that a discrepancy is detected responsive to said comparison.

13. The dispenser of claim 8 wherein said self-checking means comprises memory circuit means, means for storing in said memory circuit means a current total value of the dispensed gasoline and a current total volume of the dispensed gasoline, a power failure detector means, a totalizer shift register means powered by an independent power source, and means under the control of the power failure detector means for transferring information from the memory circuit means to the shift register means responsive to a detection of a power failure.

14. The dispenser of claim 8 and means responsive to said self checking means for indicating by a display of a coded signal the identity of a fault condition.

15. A self-checking, fluid-dispensing system comprising signalling means responsive to a flow of fluid dispensed through said system for generating electrical signals representing at least the volume of the dispensed fluid, calculating means responsive to said electrical signals for calculating the cost of the dispensed fluid in accordance with a predetermined unit price of the dispensed fluid, means responsive to said calculating means for visibly displaying the calculated cost of the dispensed fluid, self-checking means for continuously, positively and actively self-checking the validity of said visible cost display, a plurality of single pole multi-way switch means, each of said switch means being settable to a particular one of the multi-way positions to represent particular digits of the unit price, said self-checking means comprising means for simultaneously scanning the multi-way connections of each of the switch means, and means for checking to be sure that only one signal is read from the single pole of each switch means during a single scan and for shutting down the system if a fault condition exists.

16. A gasoline-dispensing system especially for retail sales, said system comprising fluid flow metering means for mechanically measuring gasoline as it is dispensed by said dispensing system and for developing fluid flow metering signals responsive thereto, memory means responsive to said signals for storing the volume of gasoline that is dispensed by said system, means for storing preselected price data in said dispensing system, means for displaying to a customer the price and amount of gasoline that is dispensed, microprocessor means for separately calculating the price of gasoline by multiplying the volume of gasoline stored in said memory means by said preselected price data set into said dispenser, and means jointly responsive to the mechanically measured volume of dispensed gasoline and to the separately calculated price for shutting down said dispensing system when an error is indicated.

17. The system of claim 16 wherein said fluid flow-metering means develops at least two trains of pulses having a predetermined relationship with each other only when said fluid flow metering means is operating in a normal manner, and means for shutting down said dispensing system when said pulses are in any relationship other than said predetermined relationship.

18. The system of claim 16 wherein said means for storing said preselected price data in said dispensing system comprices a predetermined number of switches which are separately set, means in said dispensing system for checking the number of switches which are set, and means for shutting down said dispensing system if an incorrect number of said switches appear to have been set.