US3666928A

US3666928A - Gasoline pump calculator

Info

Publication number: US3666928A
Application number: US138912A
Authority: US
Inventors: William F Burke; Daniel A Gihring; Thomas E Jones
Original assignee: PAN NOVA
Current assignee: PAN NOVA; PAN-NOVA Inc
Priority date: 1971-04-30
Filing date: 1971-04-30
Publication date: 1972-05-30
Anticipated expiration: 1989-05-30
Also published as: AU3813272A; CA958811A; IT948568B; GB1345984A; DE2206043A1

Abstract

A calculator for use in a gasoline dispenser or the like for calculating amount of sale and volume dispensed, and for displaying the amount and volume of sale and the price per gallon. A pulse generator actuated by the flow meter provides volume pulses at a relatively low rate as a function of volume dispensed. Volume pulses are counted directly for volume computation. Each volume pulse gates on a clock pulse generator running at a relatively high rate, with the on time controlled by a preset price counter. Clock pulses are counted for amount of sale computation and are counted for gate on time control.

Description

United States Patent o PULSES/GAL.

Burke et al. 51 May 30, 1972 [54] GASOLINE CALCULATOR 3,549,868 12 1970 Watson et al. ..235 92 FL [72] Inventors: William F. Burke, Westminster; Daniel A.

Gihring, Orange; Thomas E. Jones, Costa axamlfer Maynard w'lbur Mesa all of Calm Assistant ExammerJoseph M. Thesz, Jr.

Attorney-l-lar1is, Kiech, Russell & Kern [73] Assignee: Pan-Nova, Inc., Santa Fe Springs, Calif. 22 Filed: Apr. 30, 1971 [57] ABSTRACT [2!] App]. No; 138,912 A calculator for use in a gasoline dispenser or the like for calculating amount of sale and volume d1spensed, and for dplaying the amount and volume of sale and the price per gal- [52] US. Cl ..235/92 FL, 235/94 A, 235/l5l.34, Ion A pulse generator actuated by the fl meter providgs 235/92 235/92 PE volume pulses at a relatively low rate as a function of volume [51] Int. Cl dispensed volume-pulsesare counted directly for volume [58] Field of 'gff g gfij computation. Each volume pulse gates on a clock pulse generator running at a relatively high rate, with the on time controlled by a preset price counter. Clock pulses are counted [56] References Cited for amount of sale computation and are counted for gate on UNITED STATES PATENTS controls- 3,043,508 7/1962 Wright ..235/92 FL 9 Claims, 1 Drawing Figure VOL UME ACCUMULATOR ,4'/* E 0 016/771 a/spmv m .l: 23- 0 2 GALLONS CLOC'K jmhz 33 {M2 g SALE ACCUMULATOR GEM GA E 0 0 g 33 u 0 D v 23 Q5 2/ RESET 6/ 34 7 66 I w PR/CE COUNTER RESET A;CCUMULATO%5 40 D 4/ D D gggg'- Lilli 2513?? 4 42 T 54 0 36 u-r 53 LOG/C 52 g cg zo 43 05c. 0.5a. 45

DECODER 0 5 5 y v w ipaa /zli 7 49 44 SELECTORQ BACKGROUND OF THE INVENTION This invention relates to calculators for material dispensing and in particular to a new and improved electronic calculator for use with dispensers, such as gasoline and other fuel dispensing devices. The invention will be described herein as applied to a gasoline pump such as is utilized at the modern day service station. A typical gasoline dispenser includes a fluid pump, a pump control switch, a hose with nozzle for insertion into the vehicle tank, a flow control on the nozzle, and one or more manually controlled levers which function to start and stop the pump and reset the calculator. Fluid flow through the nozzle is measured, the volume of material dispensed is calculated and displayed, the cost or monetary amount of the sale of the material is calculated and displayed, and the price, e.g., cents per gallon, is displayed. Some arrangement is provided for changing the price.

Mechanical calculators have been in use for a considerable period of time in gasoline dispensers. Electronic calculators have been proposed and several are shown in existing patents. The patent to Wright, U.S. Pat. No. 3,043,508 shows an electronic. multiplier for fluid dispensers having a flow meter which generates pulses as a function of fluid flow, and provides forsampling the pulses periodically with the sampling time being preset as a function of price, with the sampling occurring in a price sealer having a first set point corresponding to the price and a second set point corresponding to the sampling rate. The flow rate pulse generator operates at a relatively high rate for this type of device, in the order of 4,000 pulses per gallon. An oscillator provides an input for the price scaler, with the oscillator operating at a relatively low frequency in the order of khz, whichis about one order of magnitude greater than the flow meter pulse rate for present day gasoline pumping rates.

The patent to Livsay US. Pat. No. 3,081,031 shows another electronic calculating apparatus with the flow meter providing an output at about 1,000 pulses per gallon, with this pulse outputbeing counted directly to provide an indication of volume. Decimal counting is utilized and certain count states of the volume counter are selected as a function of price, to provide the amount of sale figure.

Giot et al. US. Pat. No. 3,221,149 discloses-another electronic metering and computing apparatus in which the pulses from the flow and in which each pulse provides a full cycle of operation of another thirteen stage counter with the counter cycle shutting off at the 13th count and with the counter being tapped at various count states to provide inputs to an amount of sale counting unit. The th 1 1th and 12th counts are used as controls for permitting advance pulses from a lower decade to a higher decade so that these advance pulses cannot occur simultaneously with the inputs from the first nine counts of the 13 stage counter.

SUMMARY OF THE INVENTION The calculator of the invention includes a pulse generator producing electrical pulses at a relatively low rate as a function of material dispensed, and a clock generator which produces pulses ata relatively high rate. The clock output is gated on by each pulse from the pulse generator and is gated off by a price counter which is manually set to the price of the material being dispensed. The clock output is transmitted to a sale accumulator and to the price counter, with the on time being controlled by the number of clock pulses required to advance the price counter to the preset price. The sale accumulator counts the clock pulses and provides an output reading in the amount of sale. The pulse generator output may be counted directly in a volume accumulator to provide an output reading in volume. The price counter setting provides an output of price and all three outputs may be suitably displayed. Circuitry is provided for rounding off the amount of sale at the half-cent and circuitry is provided for resetting the system when the transaction is completed or when a transaction is initiated.

It is an object of the invention to provide a new and improved electronic calculator for gasoline dispensers and the like. It is a particular object of the invention to provide such a calculator which can operate with a flow meter having a low r.p.m. and a low pulse rate, permitting a low inertia system with minimal start and stop problems. A further object is to provide such a system having low rotational error, with the error being independent of the amount of sale. Additional ob,- jects include provision of manual setting which may be' applicable to a plurality of dispensing units and displays, halfcent round-ofi, and continuous indication and agreement between volume dispensed and amount of sale.

DESCRIPTION OF THE DRAWING The drawing is a diagrammatic illustration primarily in block diagram form showing a presently preferred embodiment of the calculator of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT A flow meter, such as a conventional positive displacement meter, is mounted in the pipeline l0 upstream of the dispensing nozzle. A pulse generator provides electrical pulses as a function of flow and typically may comprise a reed switch 11 actuated by one or more magnets 12 carried on a rotating shaft 13 driven by the meter. Each closure of the switch 11 connects a voltage source 14 to the input of a driver amplifier 15. The pulse generator preferably operates at a relatively low rate, typically pulses per gallon which may correspond to four meter revolutions per gallon with a 25 to 1 step up in the pulse generator, generators of this type being commercially available today. Present day gasoline pumps deliver fuel at a rate in the order of 10 to 15 gallons perminute, with a corresponding pulse generator output in the order of 25 pulses per second. Withthe pulse generator providing 100 pulses per gallon, a unit volume of material dispensed would be one one hundredths of a gallon. v

The pulse generator output pulses are referred to herein as the volume pulses, with the number of volume pulses being a direct function of the volume of material dispensed. The volume pulses are connectedas the input to a volume accumulator comprising four counter decades D connected in series. These may be conventional binary coded digital counters, with the output of each decade driving one element of the four element volume display 20. Nixie tubes or other conventional numeral display elements may be utilized.

A clock generator provides clock pulses at a relatively high rate, typically in the range of one-half to 2 mhz, with l mhz 'being used in the embodiment disclosed herein. Clock pulses are connected by a gate 21 to an output line 22. The gate 21 is a conventional circuit which is turned on to the open or transmit condition by each volume pulse on line 23 and is turned off to the blocking condition by a stop pulse on line 24. The clock pulse output from the gate is connected as an input to a sale accumulator and as an input to a price counter. The sale accumulator includes a first counter comprising three

decade counter units

30, 31, 32, connected to a second counter comprising three more

decade counter units

33, 34, 35, by a halfcent decode circuit, with the outputs of the second counter decades feeding three display elements in an amount-of-sale display 36.

The price counter has three binary coded digital

decade counter units

40, 41, 42 connected in cascade with the clock pulses as an input. The binary coded output of each decade is converted to a decimal output in a decoder 43 and the 10 output lines of the decoders are connected to 10 inputs of

selector switches

44, 45, 46. Various conventional selector switches may be utilized and'the drawing illustrates a conventional wafer switch having 10 input terminals and an output terminal '47 with the output terminal making continuous contact on a rotating conductor 48 and with a tongue 49 of the ring 48 engaging one of the 10 input terminals.

The selector switches 44, 45, 46 are set to the price of the material dispensed, typically a figure such as 37.9, representing the cost of the fuel in cents per gallon, with the switch 44 setting the least significant figure or tenths of a cent, the switch 45 setting the units and the switch 46 setting the tens. A price display 50 may include three display elements for displaying the price set by the

switches

44, 45, 46, with each switch having a second deck 44', 45, 46', respectively, for providing the signal for actuating the display element.

The output terminals 47 of the three selector switches are connected to the stop count logic circuit for producing the stop signal on the line 24 when the price counter has counted to the particular figure set by the three selector switches. The stop count logic may utilize a coincident gate of some type and the preferred embodiment has two of the switch outputs connected as inputs to a nor gate 52 and the'third switch output connected as the input to another nor gate 53, with the outputs of the two nor gates connected as inputs to a' nand gate 54. Alternatively, the set price could be binary coded and compared directly with the count state of the

units

40, 41, 42, to provide the stop signal when there is coincidence between the state of the three decades and the binary coded set price.

When the gate 21 is switched to the on condition by a volume pulse on line 23, clock pulses are transmitted to the price counter and are counted in the

decades

40, 41, 42. The gate 21 remains open until the price counter reaches a count state corresponding to the setting of the

switches

44, 45, 46. At this time, there are outputs on each of the threeoutput terminals 47, which outputs produce the stop signal on line 24 through the stop count logic circuit. The gate 21 is switched to the off condition and awaits another volume pulse on line 23. The next volume pulse resets the decades of the price counter to the initial condition via line 23' and again switches the gate to the open condition. The price counter again counts to the preset price figure and closes the gate: This cycle is repeated for each volume pulse from the pulse generator.

When the gate is in the on or open condition, the pulse train sent to the price counter is also sent to the sale accumulator, where it is counted in the cascaded decades 3035.'We will first consider the operation of the sale accumulator with the half-cent decode circuit omitted and with the decade 32 connected to the decade 33 in the normal manner. With this arrangement and for sales in dollars and cents, each clock pulse at the input of the decade 30 represents a sale of $0.0000l of material dispensed, and each pulse at the input of the decade 33 represents $0.0] or 1 cent. With this arrangement, the calculation of amount of sale and the display of the amount of sale would advance one cent at the completion of the metering of the entire one cents worth. However in many merchandising arrangements, it is desired to have the 1 cent advance occur at the half-cent of dispensing time. That is, the amount of sale will change from zero to 1 cent when one-half cent of material has been dispensed and similarly, will change from 1 cent to 2 cents when l xcents of material has been dispensed.

in the preferred embodiment of the present invention, the half-cent decode circuit between

decades

32 and 33 provides this mode of operation. The half-cent decode circuit provides for passing a pulse from decade 32 to decade 33 with the fifth input pulse of decade 32 rather than with the th input pulse, the latter being the normal mode of operating the decades in cascade. This is accomplished by utilizing a logic circuit which responds only to the fifth count state of the decade 32. With a l-2-a-8 binary coded digital counter, the l, 2 and 4 outputs are connected in a coincident circuit, as by connecting the l and 4 outputs as inputs to a nand gate 60 and connecting the 2 output to the inputs of another nand gate 61, with the output of gate 61 connected as the third input to the gate 60. The gate 61 is operated as an inverter, and a nand gate is used for convenience because the

gates

60, 61 come in a single package.

A reset circuit 65 provides a reset signal for the decades of the volume and sale accumulators. Typically this may be a switch 66 which normally connects a voltage of a battery or other source 67 to the reset terminal (not shown) of each decade. Actuation of the switch 66 to connect the switch output line 68 to circuit ground provides the reset operation. The

switch 66 may be actuated by the reset lever which is found on conventional gasoline pumps or a separate lever for actuating the switch may be provided if desired. Another set of volume and sale accumulators, which are not reset by the reset circuit, may be provided to give a total of sales for each day or other period as desired.

The calculator provides for continuous measurement, computation and display of the volume of material dispensed and of the amount of sale. The volume and the amount of sale as calculated and displayed are in agreement at all times. As indicated above, the flow meter may operate a relatively low rate, typically producing pulses per gallon or about 25 pulses per second, while the clock generator and the associated circuitry operate at a rate several orders of magnitude higher, typically in the range of one-half to 2 mhz. With a pulse generator rate of 100 pulses per gallon, the maximum rotational error due to the flow meter will be less than one one-hundredth of a gallon per transaction, and will be independent of the amount of material dispensed per transaction.

The outputs of the volume accumulator and the sale accumulator and the setting of the selector switches are displayed digitally, for operation of the gasoline pump in the same manner as the conventional pumps. However it will be recognized that the electrical outputs from the accumulators and switches may be used as inputs for computers and various data processing operations as well as for visual display. Also, each of the selector switches may be utilized to provide price setting for a plurality of dispensers, typically all of the pumps at a station, as by providingan additional deck on the wafer switch for each calculator. Further, the price setting controls and the displays may be remote from each other and from the dispenser. 1

We claim:

1. In a calculator for a material dispenser, the combination of: t I

a volume pulse generator producing volume pulses as a function of material dispensed;

a clock pulse generator producing clock pulses;

a sale accumulator including means for counting input pulses and displaying the count state for indicating the monetary amount of a sale of material;

a price counter including means for counting input pulses;

means for developing a stop signal when said price counter counts to a predetermined figure and including means for changing said figure;

a gate circuit for passing pulses from the gate input to the gate output when the gate is in the on condition and blocking pulses when the gate is in the off condition;

- means connecting said clock pulses to said gate input;

means connecting said gate output to the input of said sale accumulator and to the input of said price counter;

means connecting said volume pulses to said gate circuit in controlling relation for switching the gate circuit to the on condition for each volume pulse;

means connecting said volume pulses to said gate circuit in controlling relation for switching the gate circuit to the off condition; and v means for resetting said price counter to the initial count state for each volume pulse;

with said sale accumulator counting for each volume pulse, a number of clock pulses corresponding to the price of a unit volume of material.

2. A calculator as defined in claim 1 in which said volume pulse generator operates at a relatively low pulse rate and said clock pulse generator operates at a relatively high pulse rate at least several orders of magnitude greater than said low pulse rate.

3. A calculator as defined in claim 1 including a volume accumulator having means for counting input pulses and displaying the count state for indicating the volume of material dispensed, and

means connecting said volume pulses to the input of said volume accumulator.

4. A calculator as defined in claim 3 including price means for displaying said predetermined figure, and

means connecting said means for developing a stop signal to said price means for changing the displaying thereof when said figure is changed.

5. A calculator as defined in claim 4 including a reset circuit having a switch for actuation by the party dispensing the material, and

means connecting said reset circuit to said sale and volume accumulators for resetting them to the initial condition when said switch is actuated.

6. A calculator as defined in claim 5 in which said volume pulse generator includes a meter driving a shaft rotating as a function of flow, and a switch actuated by said rotating shaft.

7. A calculator as defined in claim 1 in which said sale accumulator includes:

a first counter having clock pulses as an input and counting to a unit-of-sale corresponding to the smallest monetary value calculated and displayed;

a second counter providing an output for each of said unitsof-sale and decimal multiples thereof; and

a half unit-of-sale decoder connecting said first counter to said second counter, said decoder transmitting a pulse from said first counter to said second counter when said decoder means for converting the count state of said price counter to a decimal code providing a multi digit decimal output;

a selector switch for each digit of the predetermined figure and having 10 inputs and an output;

means connecting each decoder means decimal output to a selector switch as inputs; and g a logic gate having each of said selector switch outputs as an input and providing the stop signal when the count state of said price counter corresponds to the setting of said selector switches.

50 UNITED STATES PATENT QFFICE v fiERHFICATE OF CQRRECTWN 3,666 928 Dated Ma 30 1972 In n William F. Burke David A. Gihring and Thomas E. Y Jones It is certified that error appears in the abovef-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1:

Line 46, after flow", insert --meter are counted directly to provide an indication of volume--; Line 50, after "10th", insert a Line 68, delete "the" [first occurrence] before "amount of sale" Column 2:

Line 72, after "conductor", insert --ring- Column 3: v v 7 Line 63, "1-2-8043" should be --l-2-4'-8-- Column 4: Q

Line 57 "volume pulses" should be --stop signal" Signed and sealed this 19th day of December 1972. v

Attest:

EDWARD MFLETCHER,JR. ROBERT GOTISCHALK Attes'ting Officer 1 Commissioner of Patents- L I x J.

' UNlTED STATES PATENT GFFICE CERTIFICATE UF CORECTFN Pate n NO- 3 666 928 v Dated May 36 g 1972 n )William F. Burke, David A. Gihring and Thomas E. 1 Jones It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

' '1 Column 1:

Line 46, after "flow", insert --meter are counted directly to provide an indication of volume--; Line 5G after "10th", insert Line 68, delete "the" [first occurrence] before "amount of sale" Y Column 2:

Line 72, after "conductor", insert --ring-- Column 3:

Line 63, "l-2a'-8" should be --l-2-4-8-- I Column 4:

Line 57, "volume pulses" should be "stop signal-- Signed and sealed this 19th day of December 1972.

(SEAL) Attesc: V

EDWARD M.FIETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents-

Claims

1. In a calculator for a material dispenser, the combination of: a volume pulse generator producing volume pulses as a function of material dispensed; a clock pulse generator producing clock pulses; a sale accumulator including means for counting input pulses and displaying the count state for indicating the monetary amount of a sale of material; a price counter including means for counting input pulses; means for developing a stop signal when said price counter counts to a predetermined figure and including means for changing said figure; a gate circuit for passing pulses from the gate input to the gate output when the gate is in the on condition and blocking pulses when the gate is in the off condition; means connecting said clock pulses to said gate input; means connecting said gate output to the input of said sale accumulator and to the input of said price counter; means connecting said volume pulses to said gate circuit in controlling relation for switching the gate circuit to the on condition for each volume pulse; means connecting said volume pulses to said gate circuit in controlling relation for switching the gate circuit to the off condition; and means for resetting said price counter to the initial count state for each volume pulse; with said sale accumulator counting for each volume pulse, a number of clock pulses corresponding to the price of a unit volume of material.

3. A calculator as defined in claim 1 including a volume accumulator having means for counting input pulses and displaying the count state for indicating the volume of material dispensed, and means connecting said volume pulses to the input of said volume accumulator.

4. A calculator as defined in claim 3 including price means for displaying said predetermined figure, and means connecting said means for developing a stop signal to said price means for changing the displaying thereof when said figure is changed.

5. A calculator as defined in claim 4 including a reset circuit having a switch for actuation by the party dispensing the material, and means connecting said reset circuit to said sale and volume accumulators for resetting them to the initial condition when said switch is actuated.

7. A calculator as defined in claim 1 in which said sale accumulator includes: a first counter having clock pulses as an input and counting to a unit-of-sale corresponding to the smallest monetary value calculated and displayed; a second counter providing an output for each of said units-of-sale and decimal multiples thereof; and a half unit-of-sale decoder connecting said first counter to said second counter, said decoder transmitting a pulse from said first counter to said second counter when said first counter has counted to one-half of a unit-of-sale.

8. A calculator as defined in claim 7 in which said first counter includes a decade counter unit counting in 10ths of said unit-of-sale and having an output for each 10th counted, and said decoder includes a logic gate having at least some of said counter unit outputs as inputs and providing an output to said second counter only for the five-tenths count state.

9. A calculator as defined in claim 1 in which said means for developing a stop signal includes: decoder means for converting the count state of said price counter to a decimal code providing a mUlti digit decimal output; a selector switch for each digit of the predetermined figure and having 10 inputs and an output; means connecting each decoder means decimal output to a selector switch as inputs; and a logic gate having each of said selector switch outputs as an input and providing the stop signal when the count state of said price counter corresponds to the setting of said selector switches.