US3009605A

US3009605A - Electronic and hydraulic pump dispensing control

Info

Publication number: US3009605A
Application number: US847950A
Authority: US
Inventors: Harold F Ripley
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-10-22
Filing date: 1959-10-22
Publication date: 1961-11-21
Anticipated expiration: 1978-11-21

Description

H. F. RlPLEY Nov. 21, 1961 ELECTRONIC AND HYDRAULIC PUMP DISPENSING CONTROL Filed Oct. 22, 1959 8 Sheets-Sheet 1 mm M &

HHROLD F/Q/PLEY INVENTOR ATTORNEYS H.-F. RIPLEY Nov. 21, 1961 ELECTRONIC AND HYDRAULIC PUMP DISPENSING CONTROL Filed Oct. 22, 1959 8 Sheets-Sheet 2 R mm km mm mm Mm Nov. 21, 1961 H. F. RIPLEY 3,009,605

ELECTRONIC AND HYDRAULIC PUMP DISPENSING CONTROL Filed Oct. 22, 1959 8 Sheets-Sheet 3 9 5 6 0 57 /53] ,1 I I I ll 1 g6 6; 5/

BY I I I ATTORNEYS.

Nov. 21, 1961 H. F. RIPLEY ELECTRONIC AND HYDRAULIC PUMP DISPENSING CONTROL Filed Oct. 22. 1959 8 Sheets-Sheet 4 /'/A/?01.0 F/F/PLEY INVENTOR ATTORNEYS Nov. 21, 1961 H. F. RIPLEY 3,009,605

ELECTRONIC AND HYDRAULIC PUMP DISPENSING CONTROL Filed Oct. 22. 1959 8 Sheets-Sheet 5 ATTORNEYS Nov. 21, 1961 H. F. RI'PLEY 3,009,605 ELECTRONIC AND HYDRAULIC PUMP DISPENSING CONTROL Filed Oct. 22. 1959 8 Sheets-Shem s ATTORNEYS Nov. 21, 1961 H. F. RIPLEY 3,009,505

ELECTRONIC AND HYDRAULIC PUMP DISPENSING CONTROL Filed OC't. 22, 1959 8 Sheets-Sheet 7 my I /69 \3 I. I 94 l I I /97 I99 HAROLD [A /P2 EV INVENTOB 1 I By /I I I ATTORNEYS H. F. RIPLEY Nov. 21, 1961 ELECTRONIC AND HYDRAULIC PUMP DISPENSING CONTROL 8 Sheets-Sheet 8 Filed Oct. 22. 1959 I IIIIQJ lllllllllnu HAROLQF/Q/PLEY IN VENTOR ATTORNEYS United States Patent Ofi 3,009,605 Patented Nov. 21, 1961 ice 3,009,605 ELECTRONIC AND HYDRAULIC PUMP DISPENSING CONTROL Harold F. Ripley, Dry Run Road, Pine City, N.Y. Filed Oct. 22, 1959, Ser. No. 847,950 8 Claims. (Cl. 222-20) This invention relates to a combined electronic and hydraulic control for liquid fuel dispensing pumps, such as are commonly used for dispensing gasolinein the tanks of automobiles and other motor vehicles. It aims to improve generally on the arrangement as shown and described in my prior Patent No. 2,828,782, dated April 1, 1958.

An object of the present invention is to provide a means for automatically dispensing gasoline or other liquid fuels, in which the amount dispensed may be determined on the basis of either the total amount desired or the total cost.

Another object of the present invention is to provide a means for and automatically dispensing gasoline, or other liquid fuels, in which the amount dispensed may be governed by either the quantity indicator or the cost computer, which are commonly parts of present day gasoline pumps.

.A further object of the present invention is to provide a means for automatically dispensing gasoline or other liquid fuels, in which thereis employed an automatic control for the quantity dispensed that may be drivably connected to either the quantity indicator or the cost computer on the conventional gasoline, or other liquid fuel dispensing pump, with a minimum of labor and at a low cost. j

A still further object of the present invention is to provide a means for automatically dispensing gasoline, or other liquid fuels, in which the quantity dispensed is predetermined by the filling station operator and then controlled by either the quantity indicator or the cost computer on the conventional gasoline pump.

Yet another object of the present invention is to provide a means for automatically dispensing gasoline or other liquid fuels, in which the dispensing of the liquid fuel is automatic, after being initiated by the filling station operator, but will be automatically discontinued if the vehicle tank should become full before the predetermined amount has been received, or will be temporarily suspended, if back pressure should be developed due to too rapid fillingof the tank, which condition would otherwise result in thetank overflowing.

Additional objects, advantages and improvements will become apparent from the following specification, taken in connection with the accompanying drawings in which:

FIGURE 1 is a side elevational view showing the dispensing nozzle, the cutoff valve, the operating electromagnet, and the hydraulic servo cylinder for operating the cutoff valve. 7 FIG. 2 is a top plan view, taken on the section line 2-2 of FIG. 1 and looking in the direction of the arrows, showing the dispensing nozzle and the cut-ofi valve. FIG. 3 is a part-side elevation and part-side sectional view, taken on the section line 3-3 of FIG. 2, and looking in the direction of the arrows, showing the cut-off valve and the hydraulic servo-cylinder for operating the latter. I FIG. 4 is a vertical sectional view, taken on the section line "4-4 of FIG. 3 and looking in the direction of the arrows, showing in detail the'construction of the cut-off valve.

FIG. 5 is a vertical sectional'view, taken on the section line '55 of FIG. 3 and looking in the direction of the arrows, showing theinternal construction of the hydraulic servo-cylinder for operating the cut-off valve.

FIG. 6 is a detail vertical view, taken on the section line 6-6 of FIG. 3 and looking in the direction of the arrows, showing in detail the overflow shut off float piston.

FIG. 7 is a side elevational view, partly in section, showing the details of the hydraulic servo cylinder and the operating electro-magnet for the latter.

FIG. 8 is a side elevational view showing the details of the fluid-operated switch for opening the circuit of the operating electro-magnet in the event of the fuel tank overflowing, or back pressure building up in the latter.

FIG. 9 is a side elevational view, partly in section, showing in part the internal components of a gasoline dispensing pump and the rotary cut-01f switch, according to the present invention connected to the computer shaft of the latter.

FIG. 10 is an end elevational view of the rotary disc of the cut-off switch, according to the present invention.

FIG. 11 is a sectional view taken on the section line 11-41 of FIG. 10, and looking in the direction of the arrows, showing internal details of the rotary cut-off switch and the cylindrical housing enclosing same.

FIG. 11A is a detail sectional view, taken on the section line 11A11A of FIG. 11, and looking in the direction of the arrows, showing the mounting of one of the brushes of the rotary cut-off switch. I

FIG. 12A is the left half of circuit diagram of electric power supply and electric the present invention.

FIG. 12B is the right half of the circuit diagram of the electric power supply and electric control circuit according to the present invention.

FIG. 13 is a side elevational view of a coin-operated switch, which may be employed in the electronic control circuit in place of the manually operated switches.

FIG. 14 is a side elevational view of the coin-operated switch shown in FIG. 13, showing the electro-magnet for swinging the lower section of the coin chute in coin disferential posing position.

FIG. 15A is a left half of the circuit diagram of FIG. 12A, showing a plurality of coin operated switches con nected in the electronic control circuit, likewise for dispensing gasoline, or other liquid fuels, in several dollar amounts.

FIG. 15B is a right half of the circuit diagram of FIG. 12C, related to the latter figure in the same manner as FIG. 15A to FIG. 12A.

FIG. 16 is a side elevational view of the coin chute structure according to FIG. 13, showing the arrangement of a plurality of the coil chutes for dispensing gasoline, or other liquid fuels, in several dollar amounts.

FIG. 17 is a circuit diagram showing the operating electro-magnet for swinging the coin chutes of FIGS. 14 and15, Io coin disposing position, connected in parallel with t e operating electromagnet for the hydraulic master cylinder, and magnet. I

7 Referring now to the drawings in detail, ,and to FIGS. 1 and 3 in particular, there is hereshown a hose 10, which exends from the conventional liquid fuel dispensing pump (FIG. 9) and terminates in a nozzle 11. Intermediate the hose 10 and the nozzle 11 there is placed a manually operated valve 13 of the rotary type. This valve functions both as a throttle and a shut-off valve. The valve 13 has a rotary valve member 14, which is formed with a circumgroove of arcuate cross section and uniformly varying depth, and whichcooperates with a cylindrical valve seat 15. The function of this valve is to limit flow of the gasoline, or other liquid fuel, through the nozzle 11 to the rate at whichthe vehicle tank (not shown) can I. receive same. It is, of course, well known that the throats control circuit according to a time delay circuit for the former electroof all vehicle fuel tanks will not always receive fuel at the same rate of flow.

A valve cylinder is comprised by upper and

lower parts

16 and 17, respectively, aligned at right angles to the nozzle 11 and intersecting a suitable bore positioned transversely of the latter. Both parts have suitable flanges 18, with screws 19 etxending through the latter into the body of the nozzle 11. Within the valve cylinder 16-17 there is slidably positioned a valve piston 20. At its lower end the piston 20 has an axial bore 21 therein, in which is seated one end of a compression spring 22, the other end of this spring seating in a recess 23 in the lower end 17 of the valve cylinder. At its upper end the valve piston 20 is formed as a segment 24 of a spherical surface, which is complementary to a valve seat 25 in the upper end 16 of the valve cylinder, the latter seat also being formed as a segment of a spherical surface. A rod 26 is positioned axially of the upper end of the valve piston 20 and extends through a suitable bushing 27 in the upper end 17 of the valve cylinder.

Thet servo hydraulic operating cylinder is shown at 28. It is closed at its outer end by a cap 29. This cylinder is secured to the nozzle 11 in any suitable manner, such as by having a flange 30 thereon, through which suitable bolts or screws 31 extend into the body of the nozzle. Between the servo hydraulic operating cylinder 28 and the valve cylinder 16--17, there is positioned a suitable housing 32, which encloses the upper end 16 of the valve cylinder, and partially encloses the servo hydraulic operating cylinder itself, and also encloses selected parts, to be now described. The housing has a flange 38 at its lower outer end, through which bolts or screws 34 extend to secure same to the nozzle 11, and is also secured to the servo hydraulic operating cylinder 28 by bolts or screws 34. A filler block 35 is placed between the housing 32 and the servo hydraulic valve operating cylinder 28.

Within the servo hydraulic valve operating cylinder 28 there is reciprocably mounted a piston 36. This piston has an axially positioned rod 37, which is secured thereto by a nut 38, and the rod slidably extends through the outer end 29 of the servo hydraulic valve operating cylinder. Around the piston rod 37 there is a coiled compression spring 39, which is positioned intermediate the piston 36 and the outer end 29 of the servo hydraulic valve operating cylinder 28.

At its outer end the piston rod 37 abuts one arm 40a of a bell crank lever. This bell crank lever is pivotally mounted on a bolt 41, which extends between the side walls of the housing 32. The other arm 40b of the bell crank lever rests on the top of the valve piston rod 26. A manual operating means for the valve piston rod 20 is also provided. This means is comprised by a rod 42, which rests on the lower end of the arm 40b of the bell crank lever, in alignment with the valve piston rod 26. At its upper end the rod 42 is slidably mounted in a suitable bushing 43 in the housing 31 and exteriorly of the housing carries a knob 44.

A hollow boss 45, closed by a suitable screw cap 46, is formed on the servo-hydraulic valve operating cylinder 28, to provide a vent for releasing air from the liquid supply line, to be now described, and to insure thereby the instantaneous and positive action of the piston 36.

The operating fluid for the servo hydraulic valve operating cylinder 28 is transmitted to the cylinder by a tube 48, which is secured to the cylinder by a suitable coupling :7. This tube 48 extends to the master hydraulic cyliner. The master hydraulic cylinder 50 and the operating electro-magnet therefor are shown in FIG. 7. The tube 48 is connected to the cylinder 50 by a suitable coupling 49. A hollow boss 51 on the cylinder 50, closed by a suitable screw cap 57, is provided as a means for filling the cylinder, and the tube 48, with the operating liquid. The cylinder 50 is integrally formed with a supporting base 52, which may be secured to any suitable support by bolts 53. Within the cylinder 50 there is reciprocally mounted a piston 54 and a piston rod 55 is secured axially to the latter. This piston rod is slidably mounted in a suitable bushing 56 in one end of the cylinder 50.

The operating electro-magnet for the hydraulic master cylinder 50 is comprised by a multiple layer wound coil 60, having outwardly extending leads 183 and 184 (see FIG. 12B. The coil is enclosed within a shell member 58, to which there are secured end plates 59. The shell member 58 is mounted in any suitable manner, on a base 61, which may also be secured to any suitable support, as by bolts 53. A core 63 of paramagnetic material is slidably mounted within the coil 60. This core 63 has axially secured thereto a rod 64, which is slidably received in a suitable bushing 65, the latter being mounted in one end wall 59 of the solenoid enclosing shell 58. A coiled compression spring 66 surrounds the rod 64 and is positioned intermediate the plunger 63 and the end wall 59. At its outer end the rod 64 is connected by a coupling 67 to the piston rod 55 of the hydraulic master cylinder.

The means for stopping the delivery of the gasoline, or

other liquid fuel, in the event the vehicle tank should become full before the latter has received the predetermined amount of fuel, or in temporarily stopping same in case back pressure builds up in the vehicle tank, is compressed by a hydraulic system which operates a fluid responsive electric switch. As shown in FIGS. 3 and 6, a block 68, having a longitudinal bore therethrough, is secured within the nozzle 11, and adjacent the end of the latter, by a screw 69. A float piston 70 is reciprocally mounted in the bore of the block 68. To the upper end of the block 68 there is connected a tube 71, which extends lengthwise of the nozzle 11 and leaves same through a boss 12 in the nozzle. The internal tube 71 is connected to an external tube 73 by a suitable coupling 72. This external tube 73 may, if desired, be made in two parts united by a second coupling 72, which latter is positioned in alignment with the junction of the hose 10 and the nozzle 11. The positioning of the second coupling 72 at this point will obviously facilitate the disconnection of the nozzle 11 from the hose 10. The tube 73 extends to a fluid operated switch 75 (FIG. 8). The movable element of this switch is comprised by a diaphragm 79, which latter forms the end wall of a substantially hemi-spherical chamber 75. At its rear end the hemi-spherical chamber 75 is formed with a first hollow threaded boss 76, to which the tube 73 is connected by a suitable coupling 74. The chamber 75 is also formed with a second hollow threaded boss 77, which is closed by a suitable screw cap 78. This latter hollow boss forms a filling opening for introducing the operating fluid into the chamber 75 and the tube 73. The diaphragm 79 has a rod 80 positioned centrally thereof for operating the switch contacts.

Two resilient leaf switch springs 81 and 83 are mounted in parallel relationship and have normally abutting

contacts

82 and 84, respectively, thereon. The switch spring 83 is longer than the switch spring 81 and is abutted by the diaphragm rod 80. Conductors 183 and 184 (see FIG. 12) are connected to the outer ends of the switch springs 81 and 83, respectively.

, The mounting means for the resilient switch springs 81 and 83 is comprised by the usual pile. A lower insulating block 85 and an intermediate insulating block 85 are positioned on the opposite sides of the switch, spring 81, and the intermediate insulating block 85 and an upper insulating block 85 are positioned on the opposite sides of the switch spring 83. Screws 86 are surrounded by suitable insulating bushings 87 and extend through the upper insulating block 85, the upper switch spring 83, the intermediate insulating block 85, the lower switch spring 81, theslsower insulating block 85, and into a suitable support at Referring now to FIG. 9, there are here shown the related parts of a liquid fuel dispensing pump. The casing tion with the circuit 11A. A disc112 of Micarta,

of the pump is designated generally at 190. A vertically positioned pipe 92 extends from a pump 94, mounted in the lower part of the casing 90.

An electric motor 95 is drivably connected to the pump 94. It will be understood that a conventional manually rotated crank (not shown) is also provided foroperation of the pump, in case of power failure. The gasoline, or other liquid fuel, is drawn by the pump 94 from an underground tank (not shown) through a pipe 96 the usual by-pass 97 being provided between the

pipes

96 and 92 and around the pump 94. I

The computer is designated generally at 100 and is comprised in part by a housing having windows in its front wall, through which the numeral discs 101a, 1011), 101a and 101d are visible. The numerals 101a and 101b indicate the dollar amount and the numerals 101a and 1010! indicate the cents amount of the sale. A drive shaft 102 extends longitudinally of the housing 100. It will be understood that the numeral disc 10111 is secured to the shaft 102 and the numeral discs 101a, 1010 and 101d are freely mounted thereon. Also, that the numeral disc 101a is drivably connected to the shaft 102 by a speed multiplying gearing in a ten-to-one ratio, the numeral disc 101:: being drivably connected to the shaft by a speed reduction gearing in a one to ten ratio and the numeral disc 101d is drivably connected to the shaft by a speed reduction gearing in one to a hundred ratio. These speed multiplying and speed reduction gearings are commonly called transfer mechanisms. Since they are not related in any way to the present invention, they are not illustrated or further described. As the present invention is principally concerned with dispensing gasoline, or other liquid fuels, in even dollar amounts, and primarily concerned with dis pensing same in amounts of not more than five dollars worth, or with dispensing numbers of gallonscorresponding to the even dollars, and again ordinarily not more than the number of gallons corresponding to five dollars, the drive shaft 102 will hereinafter be termed the dollar shaft.

As in the conventional arrangement, there is a mechanical drive between the meter 98 and the computer 100, only a part of this drive, the shaft 99, being shown. At one end of the computer shaft 102 there is a reset handle 103 for returning the numeral discs 101a, 101b, 101a and 101d to their zero positions after the dispensing operation has been completed. A pipe 104 extends from the meter 98 to a sight glass 105 on the exterior of the casing 90 and the hose is connected to this sight glass. When not in use, the hose 10 is hung on a hook106 on the casing '90.

' A cylindrical housing 107 is mounted on the side of the casing 90 and encloses the rotary cut-off switch, which is part of the present invention. A cable 108 extends through the wall of the casing 90 and into the cylindrical housing 107, this

cable carrying conductors

168, 169, 170, 171, 172 and 181, as will be explained in connecdiagram of FIGS. 12A-12B.

The rotary cut-off switch isshown in FIGS. 10 and 11, and the associated brushes andtheir mounting in FIG.

or other suitablecomposition insulating material, comprises the principal component of the rotary cut-off switch. This disc 112 has a shaft 111 positioned axially thereof, which shaft is drivably connected to the dollar shaft 102 of the computer by a suitable coupling 110. The disc 112 and associated parts are enclosed within the cylindrical housing 107.

As shown in FIG. 10, the disc 112 has arcuate contacting

segments

114, 116, 118 and 120 spaced inwardly toward the center. Each segment begins at the 0-0 line, which is the horizontal axis to the left of the vertical axis, and the segments are of progressively increasing arcuate length radially inwardly. An inner conducting ring 122 is positioned intermediate the innermost arcuate conduct ing segment 120 and the shaft 111. The

arcuate conducting segments

114, 116, 118 and 120, and'the inner conducting ring 122 are made of copper, or'any other suitable conducting metal, and are embedded in annular grooves in the face of the disc 112. As regards the

arcuate conducting segments

114, 116, 118 and 120, the portions of the annular grooves intermediate the ends of same are filled with suitable insulating material, preferably the same materialas that of the disc itself. The arcuate lengths of the conducting

segments

114, 116, 118 and 120, are so related that the product of these lengths by the respective radial distances of the conducting segments from the axis of the shaft 111 are in a 1:2:3z4 ratio. A conductor 123 in the form of a strip of metal is embedded in a radially positioned groove along the line 00 and interconnects the

arcuate conducting segments

114, 116, 118 and 120, and the inner conducting ring 122. As will be explained in connection with the circuit diagram of FIG. 19, the

arcuate conducting segments

114, 116, 118 and are parts of the control circuit for dispensing one, two, three and four dollars worth of gasoline, or other liquid fuel, or gallons of the latter corresponding to these monetary amounts, the inner conducting ring being a part of the control circuit for dispensing gasoline, or other liquid fuel, without regard to any definite cost or in an indeterminate amount.

The

brushes

113, 115, 117, 119 and 121, which respectively contact the

arcuate conducting segments

114, 116, 118 and 120, and the inner conducting rings 122, are mounted on a strip 126 of insulating material by screws 127 This strip 126 is secured within the cylindrical housing 107 in any suitable manner.

Conductors

168, 169, 170, 171 and 172 (see FIG/11), carried by the cable .108, are connected respectively to the

brushes

113, 115, 117, 119 and 121; conductor 181, also carried by the cable 108, is connected to the brush 121.

It will be apparent that while the rotary cut-off switch has been shown as directly connected to the Dollar shaft 102 of the computer, to deenergize the control circuit after a precost amount of gasoline, or other liquid fuel, has been dispensed, it could be as well connected to the drive shaft 99, between the meter 98 and the computer 100, so as to deenergize the control circuit after a predetermined volume of gasoline, or other liquid fuel, has been dispensed.

Referring now to the circuit diagram of the electrical power supply and the electronic control circuit, as shown in part in FIG. 12B, there are here shown at 128 and 129 the two sides of a 110 volt, 60 cycle, alternating current power line. The

conductors

128 and 129 are connected to the live side of a two pole, single throw switch 130, which has fuses 131 in its base. In localities where the ordinances require. fire protection for automatic liquid fuel dispensing pumps, when the latter are mounted on an island, an electric circuit breaker can be used in place of the switch 130. Such a circuit breaker should be of the type that is electrically closed, mechanically held closed, and electrically opened or deenergized.

Conductors

132 and 133 connect the opposite terminals of the double pole and single throw switch to the heater element 134 of 11726 rectifier tube 135. One cathode 137 of tube is connected by a shunt'conductor136 to the conductor 132, and one plate 139 is connected by a shunt conductor 138 to the conductor 132; the other cathode 137 and the other plate 139 are connected by conductors 140 and 141 respectively, to the first and second terminals 142 and 144 on the live side of a fourpole, single throw switch 150.

. A filter circuit is comprised by capacitors C-1 and C-2 and a resistor R-l, the capacitor C-l being connected on one side to the conductor 140, the capacitor C-2 being connected on one side to the conductor 141, and the resistor R-1 on one side to both the capacitors C-1 and 0-2 and on the other side to the conductor 133.

This filter circuits levels otf the peaks of the waves and smooths out the ripples to maintain a constant D.C. output from the rectifier tube 135.

The circuit for the pump motor 95 is comprised on one side by a conductor 151, which extends from the conductor 132 to a third terminal 146 on the live side of the four-pole, single throw switch 150, the third terminal 147 on the opposite side of this switch, and over the conductor 153 to the motor; the other side of the circuit is from the conductor 133, over a conductor 152, to the fourth terminal 148 on the live side of the switch 150, the fourth terminal 149 on the opposite side of this switch, and over a conductor 154 to the motor.

The four-pole single throw switch 150 is enclosed by a housing which is mounted in the lower part of the pump casing 90. The switch has a handle 155 which is connected by a link 156 to a lever 158. The lever 158 is pivoted at 157 inwardly of the pump casing 90 and extends exteriorly of the casing.

The principal component of the electric control circuit according to the present invention is five 5823 type electron discharge tubes T-1, T-2, T-3, T-4 and T5, corresponding respectively to the

arcuate conducting segments

114, 116, 118 and 120, and the inner conducting ring 122. These tubes function in the control circuit according to whether one dollar, two dollars, three dollars, or four dollars worth respectively, of gasoline or other liquid fuel, is to be dispensed; the tube T- functions in the control circuit when gasoline, or other liquid fuel, according to an indefinite cost amount is to be dispensed. Alternatively, the tubes T-l, T-Z, T3 and T-4 may function in the control circuit according to whether a number of gallons of gasoline, or other liquid fuel, corresponding to one dollar, two, three or four dollars, is to be dispensed, and the tube T-5 may function in the circuit when an indeterminate number of gallons is to be dispensed. The 5823 electron discharge tube is a gas type tube, once firing has been initiated, will continue to fire until either an anode or cathode circuit has been interrupted. Each tube contains three (3) elements, a starting or firing electrode 165, a cathode 166, and an anode or plate 167. The starting or firing electrode 165 is positioned in close proximity to the anode or plate 167.

The positive side of the D.C. circuit for the control tubes T-1, T-2, T-3, T-4 and T-5 is from the first terinrnal of the four-pole, single throw switch 150, which terminal is in circuit with the first terminal 142 on the live side of the switch and the conductor 140, when the switch is closed, through a current limiting resistor R2, and over a conductor 159, which latter is common to the cathodes of all the tubes T-l, T-2, T3, T-4 and T5. A series of switches 8-1, 8-2, S3, 84 and 8-5 is provided for the firing electrode circuits of the tubes T-1, T2, T3, T-4 and T-5, respectively. Each of the switches is connected on one side to the conductor 159 and on the other sides they are connected to current limiting resistors R-3; the latter are in turn connected by conductors 160 to the respective starting or firing electrodes 165 of the tubes T-1, T-2, T-3, T-4 and T-5. The circuits for the cathodes 166 of the tubes are from the conductors 160, over shunt conductors 161, to one side of parallel RC circuits, the latter being comprised by resistors R4 and capacitors C-4; the other sides of the R-C circuits are connected by conductors 162 to the cathodes 166 of the respective tubes. These R-C circuits function to prevent feed back from the cathodes 166. The anodes or plates 167 of the tubes T-l, T-2, T-3, T-4 and T-5 are interconnected by a conductor 164. The anode or plate circuit is from the conductor 159, through a normally closed switch S, and over a conductor 163 to the conductor 164. The cathodes 166 of the tubes T-l, T-2, T-3, T4 and T-S are connected by

conductors

168, 169, 170, 171 and 172, respectively, to the

brushes

113, 115, 117, 119 and 121 for the

arcuate conducting segments

114, 116, 118 and 120, and the inner conducting ring 122, of the rotary cut-off switch.

The common circuit through the normally closed switch S to the anodes or plates 167 of the electron discharge tubes T-1, T-2, T-3, T4 and T-5 is always completed, unless the switch S is opened manually, and this places a positive potential on the plates. Due to the fact that the distance from the cathode 166 to the plate 167 of each tube is rather great, it is impossible for the tube to fire. To cause the tubes to fire, each tube is provided with starting or firing electrode 165, which electrode is positioned considerably closer to the cathode, and the tube may be fired by placing a positive potential on this starting electrode. Such positive potential is placed on the starting electrode 165 of any one of the tubes by momentarily closing the respective normally open switch S-l, S2, S-3, etc. Due to the close proximity of the starting electrode 165 to the cathode 166, an arc is established between these two elements and this arc in turn ignites the gas in the tube itself. The ignited gas now forms an electron bridge over which the current flows from the plate 167 to the cathode 166. Even though the respective switch S-l, S-2, S-3, etc., should now be opened, the current will continue to flow across the electron bridge from the plate 167 to the cathode 166, until the circuit is interrupted by the rotary cut-off switch, or by the normally closed switch S being operated.

The negative side of the D.C. control circuit is from the second terminal 145 on the outlet side of four-pole, single throw switch 150, which terminal is in circuit with the second terminal 144 on the live side of the switch and the conductor 141, when the switch is closed, over a conductor 174 to D.C. relay 175; the other side of the winding of the relay 175 is connected by a conductor 181 to the brush 121 for the inner conducting ring 122 of the rotary cut-off switch. As previously stated, the

arcuate conducting segments

114, 116, 118 and 120, and the inner conducting ring 122, of the rotary cut-off switch are interconnected by a conductor 123.

The D.C. relay 175 has an armature 176, which is biased to open circuit position by a spring 177, an armature contact 178 and a fixed contact 179. The local circuit of this relay is from the conductor 133 over a conductor 180, to the fixed contact 179; the other side of the circuit is in part from the armature contact 178 and over a conductor 183 to the operating electro-magnet 60 for the hydraulic master cylinder 50; the other side of the winding of the electro-magnet 60 is connected by a conductor 184 to the fixed contact 82 of the fluid pressure operated switch '75; the movable contact 84 of this switch is connected by a conductor 185 to the conductor 132.

The operation of the electronic and hydraulic control should now be apparent from the preceding description. Let it be supposed that it is desired to dispense a dollars worth of gasoline, or other liquid fuel. It is assumed that the main line switch 150 is closed, or if a circuit breaker is used, that the latter is closed, since this switch, or circuit breaker, is mainly a protective device for deenergizing the station for an extended period of time, or in an emergency, such as a fire. The operator opens the manually operated valve 13 and closes the four-pole, single throw switch 150 by shifting the lever 158 (FIG. 9) The circuit for the pump motor is completed from the conductor 132, over the conductor 151 to its third terminal 146 on the live side of the four-pole, single throw switch 150, the third terminal 147 on the opposite side of the switch, and over the conductor 153; also, from the conductor 133, over the conductor 182, to the fourth terminal 148 on the live side of the switch 150, the fourth terminal 149 on the opposite side of the switch and over the conductor 154, to the motor.

Rectifier tube is energized from

conductors

132 and 133 and develops a full wave D.C. voltage across conductors and 141.

The operator now closes the switch 8-1 for the electron discharge tube T1. The positive side of the primary circuit of the D.C. relay is in part from one cathode 137 of the rectifier tube 135, over the conductor 140, to the first'terminal 142 on the live side of the fouroperated'switch 75, and over the terrupted. The D.C.-relay 9 pole, single throw switch 150, the first terminal 143 on the opposite side of the switch, through resistor R-2, over conductor 159, through switch S-1, and over conductor 160 to the starting or firing electrode 165 of the electron discharge tube T-l. On account of the close proximity of the starting or firing electrode 165 to the anode or plate 167, a short are between the two elements will be formed and the gas in the envelope of the tube will be ignited. An are comprised by a stream of electrons will shortly be formed between the cathode 166 and the anode or plate 167. The tube is now firing. It will continue to fire until either the anode or plate circuit or its cathode circuit is interrupted. The positive side of the DC. circuit for the relay 175 is completed from the cathode 166 of the tube Tl, over the conductor 168, to brush 113, arcuate conducting segment 114, conductor 123, in-

ner conducting ring 122, brush 121, and conductor 181, to the winding of the relay.

The negative side of the circuit for the relay 175 is from one anode or plate 139 of the rectifier tube 135, over its conductor 141, to the second terminal 144 on the live side of the four-pole single switch 150, the second terminal 145 on the opposite side of this switch, and over the conductor 174 to the other side of the winding of the relay. The relay is now energized and armature contact 178 is closed on fixed contact 179.

The circuit for the operating electro-magnet 60 for the hydraulic master cylinder 50 is now complete, this circuit being in part from the conductor 133, over the conductor 180, the contacts 179 and '178. of the relay, and the conductor 183 to one side of the winding of the operating electro-magnet 60; the remainder of the circuit is from the other side of the winding of the operating electro-magnet, over a conductor 184, throughthe normally closed contacts 82 and '84 of the fluid pressure conductor 185, to the conductor 132. The operating electro-magnet is now energized and the core 63 is drawn toward the right (FIG. 7), against the action of the compression spring 66, to a central position within the Winding60.

The movement of the core '63 of the operating electromagnet 60 toward the right is transmitted through the rod 64 and the piston rod 55 to the piston 54 inthehydraulic master cylinder 50. Liquid is expelled from the hydraulic master cylinder 50 and passes outwardly through the tube 48.

The liquid expelled from thehydraulic master cylinder 50 passes through the tube 48 and enters the hydraulic servo cylinder 28. The piston 36in this cylinder is forced outwardly, against the action'of the compression spring 39, and the piston rod 37 partially rotates the bell crank lever 40 in theclockwise directiontFIG. 3). Valve rod 26 is depressed by the downward swinging-movement of the arm "40b of the bell crank lever, valve piston 20 is correspondingly moved downwards, against the action of compression spring '22, and upper end 24 of the valve piston is moved away from the valve seat 25 in the upper valve housing 16. The gasoline, or other liquid fuel, may now flow freely through the hose 10 and nozzle 11.

In the above described circuit the brush 113 has traveled along the arcuate conducting element 114 rm'm the -0 line (FIG. to the opposite endof the segment, while the dollar shaft of the computer has rotated to an extent to disperse one dollars worth of gasoline, or other liquid fuel, ora number of gallons corresponding -to one dollar. When the brush 113 has passed oif the arcuateconducting segment 114 and slides on the insulating material of the rotary disc 112, 'the cathode circuit of the electron discharge tube T-l is in- 175 will now open, interrupting the circuit through the winding'of the'opcrating electro-rnagnet 60 for the hydraulic master cylinder. The core 63 within the electro-magn'et 60 willnowbe moved to the left (FIG. 7) by the spring 66, and the'latterwill to their normal stored to its normal fire. cathode circuit for the tube T-3 is over the conductor 10 also move the piston 54 in the hydraulic master cylinder 50 to the left through the rod 64 and the piston rod 55. Movement 'of the piston 54 to the left within the cylinder 50 will draw liquid through the tube 48 from the hydraulic servo cylinder 28. Compression spring 39 now moves piston 36 within the hydraulic servo cylinder 28 to left (FIG. 3) and a'compression spring 22 moves valve piston 20 upwardly, with its valve surface 24 coming against the valve seat 25 in the upper valve housing 16. The flow of gasoline, or other liquid fuel, through'the hose 10 and the nozzle 11 is now discontinued.

of the vehicle 's'hould incorrectly read the gasoline gauge,

or for some other reason improperly inform the operator of the filling station as to the cost amount or the vlume of gasoline, or other liquid fuel, to be delivered 'to the vehicle tank. In such case the filling station operator will open the normally closed switch S, which interrupts the circuit to the anode or plate 167 of the electron discharge tube Tl. The DC. relay 175 is then released, the core 63 of the operating electro-magnet 60 for the hydraulic master cylinder 50 and the piston 54 in 'the hydraulic master cylinder are restored positions by the compression spring 66, in the hydraulic servo cylinder 28 is reposition by the compression spring 69, and the piston valve 20 is restored to its normal pothe piston 36 "'sition by the compression spring 22, all'as above described. I

When his desired to dispense gasoline, or other liquid fuel, in greater amounts than one dollars worth, or in greater amounts than the number of gallons corresponding to one dollar, the operation of the control circuit is the same as above described, with the exception that either the switch S2, the switch S3, or its switch -S-4, corresponding to the electron discharge tubes T2, T-3 and T4, respectively, is closed. Closing the switch 8-2 will cause the tube T-2 to fire. This circuit is then the same as previously described, except that the cathode circuit for the tube T-2 is over the conductor 169'to the brush 115, the arcuate conductingsegment 116 of the rotary cut-off switch, and over the conductor 123,

"the inner conducting ring 122, the brush 121 andthe conductor 181 to the winding of the DC. relay 175. Since the arcuate conducting segment 116 is longer than the arcuate conducting segment 114, the brush 115 will not ride off this segment, and interrupt the cathode circuit of theelectron discharge tube T-2, until the dollar shaft 102 of the computer has rotated to an extent such that two dollars worth of gasoline, or other liquid fuel, or anumber of gallons corresponding to two dollars cost,

has been dispensed.

Similarly, if it is desired to dispense three dollars worth of gasoline, or other liquid fuel, or a number of gallons corresponding to three dollars cost, the switch S-3 corresponding to the discharge tube T3, is closed. Closing of the switch 8-3 will cause the tube T3 to As before, the circuit is the same, except that the '171, to the brush 117, the arcuate conducting segment !118, the conductor 123, the inner conducting ring 122 and the brush 121 'of the rotary cut-off switch and the conductor 181 to one side of the winding of DC. relay 175. Again the arcuateconducting segment 118 is longer than either the arcuate conducting segment 114 or the arcuate conducting segment 116, and the brush 117 will not ride offthe segment 116 and interrupt the cathode circuit of the electron discharge tube T3, until the dollar shaft 102 of the computer has rotated to such anextent that three dollars worth of gasoline, or other or in a predetermined amount, it may gasoline,

gasoline, or other liquid fuel,

liquid fuel, or a number of gallons corresponding to three dollars cost, has been dispensed.

Likewise, if it is desired to dispense four dollars worth of gasoline, or other liquid fuel, or a number of gallons corresponding to four dollars cost, the switch S 4, corresponding to the electron discharge tube T-4, is closed. Here, also, the circuit is the same, except that the oathode circuit for the tube T-4 is over the conductor 171 to the brush 119, the arcuate conducting segment 120, the conductor 123, the inner conducting ring 122, and the brush 121 of the rotary cut-off switch, and the conductor 181 to one side of the winding of the DC. relay 175. As before, the arcuate conducting segment 120 is longer than the respective

arcuate conducting segments

1114, 116 and 118, and the brush 119 will not ride off the segment 122 and interrupt the cathode circuit of the electron discharge tube T-4, until the dollar shaft of the computer 100 has rotated to such an extent that four dollars worth of gasoline, or other liquid fuel, or a number of gallons corresponding to four dollars cost, has been dispensed.

In all of the above described circuits the action of the rotary cut-off switch is relatively instantaneous, its function of interrupting the several circuits being performed rapidly enough to prevent any override on the amount of gasoline, or other liquid fuel, being dispensed. Also, in the case of each of the latter three circuits described, the cathode circuit of the respective electron discharge tubes, may be interrupted if it be desired to terminate the dispensing of the gasoline, or other liquid fuel, before the predetermined cost amount, or the predetermined volume amount has been dispensed, this being done in the same manner as described in connection with the first described circuit for dispensing a dollars worth or a number of gallons corresponding to dollars, that is by depressing the normally closed switch S. It will be noted that the anode or plate circuits for all the electron discharge tubes T-1, T2, T-3, T4 and T-S, are through this switch. In the event of back pressure developing in the vehicle tank, or same being full before the predetermined cost amount, or volume amount, of gasoline, or other liquid fuel, has been delivered to same, the further delivery is stopped by the cathode circuits of the electron discharge tubes T-1, T-2, T-3, T-4 and T5, being interrupted through the fluid pressure operated switch '75 opening its

contacts

82 and 84, in a manner to be later described.

Let it now be assumed that it is desired to dispense or other liquid fuel, without regard to any cost amount, or in an indeterminate quantity. The switch S-S, corresponding to the electron discharge tube T-5, is closed. In this case the circuit is again the same as those previously described, except that the cathode circuit for the tube T-S is over the conductor 172 to the brush 121 of the rotary cut-off switch, and over the conductor 181 to one side of the winding of the DC. relay 175. The rotary cut-off switch 112 performs no function in this case of dispensing Without regard to any cost amount or in an indeterminate quantity. The dispensing of the gasoline, or other liquid fuel, may, however, be stopped at any time by the operator depressing the normally closed switch S, to open the cathode circuit of the tube T-S, or by the fluid pressure operated switch 75 opening the local circuit of the relay 175 in response to back pressure in the vehicle tank or the tank being filled, in a manner to be now described.

Upon completion of'the dispensing operation of one, two, three or four dollars worth of gasoline, or other liquid fuel, or an amount without regard to cost, or an indefinite quantity, all as previously described, the operator will remove the nozzle 11 from the vehicle tank (not shown), close the shut-off valve 13, hanging the hose on the hook 106 (FIG. 9). The operator will also open the four-pole, single throw switch 150 by shifting the lever 158 and rotating the handle 103 to return the numeral discs of the computer 100 to their zero positions. This zeroing of the computer 100 will partially rotate the disc 112 of its rotary cut-01f switch in the clockwise direction (FIG. 10 or FIG. 9, looking toward the left) to a position where the

brushes

113, 115, 117, 119 and 121, are on the 00 line at the beginning of the arcuate

commutator seg ments

114, 116, 118, 120, and on the inner conducting ring 122.

In the event that bae'k pressure should build up in the vehicle tank, due to too rapid filling, the float piston 70 will be moved upwardly within the bore of block 68. The same thing will also happen if the vehicle tank should be filled to the point of overflowing before the predetermined volume of gasoline, or other liquid fuel, has been delivered to same. Since liquids are inherently incompressible, the pressure will be transmitted through the operating liquid in the connecting tubes 71 and 73, to the chamber of the fluid pressure operated switch 75. The diaphragm 79 of this switch will be flexed outwardly and the rod 80 will force the leaf spring 83 outwardly, separating the contact 84- from the contact 82. The cathode circuit for whichever of the electron discharge tubes T-1, T-2, T-S, T4, or T-5, happens to be functioning, will now be interrupted.

When the back pressure in the vehicle tank has subsided or when the nozzle 11 has been removed from the throat of the vehicle tank, according to the activating medium for the float piston 70, the diaphragm 79 of the fluid pressure switch will move inwardly due to its inherent resiliency and the leaf switch spring 83 will move toward the leaf switch spring 81, allowing the contact 84 to close on the contact 82. The cathode circuit for the respective electron discharge tubes T-l, T-2, T-3, T-4, or T-S is now again complete. The float piston 70 is returned to its normal position, due both to the pressure of the operating liquid in the connecting tubes 73 and 71 from the inwardly flexing diaphragm 79, and to gravity.

in the event that the above described control circuit should become inoperative, for instance, due to power failure, the operator may still dispense gasoline or other liquid fuel, by depressing the valve piston 20 through the knob 44 and the rod 42, and operating the pump through the manually rotatable crank (not shown). The same would be done if it should be desired to dispense less than a gallon of gasoline, or other liquid fuel, or a quantity of the latter according to a predetermined cost, less than the cost of a gallon.

In some cases, the owners of filling stations may desire to have same of self service variety, so as to be able to dispense gasoline, or other liquid fuel, when the operator is not on duty, that is at night and on Sundays and holidays. in such cases, the manually operated switches S1, S-2, S-3, 3-4 and S5 are replaced by coin-operated switches. One such type of switch that may be used is shown in FIG. 13. A stationary coin chute 190 extends from a coin slot (not shown) in the pump casing (FIG. 9). At the base of the stationary coin chute a movable coin chute 192 is swingably mounted, by a hinge 191. As a replacement for the switch S-l, the lower coin chute 192 may be of sufficient length to accept either four (4) quarters or two (2) half dollars. Below the swingable lower coin chute 192, when the latter is in its normal vertical position, there are positioned two co-operating leaf switch springs 193 and 195, carrying movable and fixed

contacts

194 and 196, respectively. The length of the upper leaf switch spring 193, and it modulus of elasticity, are so selected, that it will be depressed by the combined weight of either four (4) quarters or two (2) half dollars, to bring the movable contact 194 into engagement with the fixed contact 196.

The mounting for the leaf switch springs 193 and 195 is similar to that for the leaf switch springs 81 and 83 of the fluid operated switch 75 (FIG. 8). A pile is comprised by upper and intermediate insulating blocks 197 positioned on the opposite sides of the upper leaf switch insulating blocks 197, the upper leaf springs 193, the intermediate insulating block 197, the lower leaf spring 195, the lower insulating block 197 and into a suitable support at 201. The conductor 159, FIG. 12, is secured to the lower leaf switch spring 195 and conductor 160 to the upper leaf spring 193.

FIGS. 15A and 15B show five of the coin operated switches according to FIGS. 13 and 14, connected in the electroniccontrol circuit, according to FIG. 12, and replacing the manually operated switches S-l, S2, 8-3, 8-4 and S5, to the electron discharge tubes T-l, T-2, T3, T-4 and T-5, respectively. The normally closed manually operated switch S, for the common anode or plate circuits of these tubes, is retained in this substitute circuit. n

Referring now to FIG. 14,.there is here shown the electro-magnet for'moving the swingable lower section 192 of the coin chute from the switch closing position to coin disposing position (shown in dotted lines). This electromagnet circuit consists of a winding 200 enclosed by a suitable casing 202, the latter having a lower flange 203 thereon. Screws 204 extend through the flange 203 and intoa suitable support 205, for mounting the electromagnet. Circuit connections for the electro-magnet 200 are over conductors 221 and 222, and will be described in connection withthe circuit diagram of FIG. 17. The

electro nagnet has mounted axially thereof a core 206 of paramagnetic material and a rod 207 is secured to this core in any suitable manner, as by screw threads. A first collar 208 is positioned around the rod 207, slidably receiving same, and a second collar 209 is positioned around the rod and secured thereto by a pin 211. Intermediate the

collars

208 and 209, there is positioned a coiled compression spring 210. At its outer end the rod 207 carries a second pin 212, which is slidably received in a slot 213 in the lower swingable section 192 of the coin chute.

It will be apparent that when the .electro-magnet 200 is energized in a manner to be later. described, the core 206 will be drawn centrally of same and the rod 207 will swing the lower section 192 of the coin chute to the dotted line position. Intermediate the switch closing position andthe coin disposing position, shown in dotted lines, the coins are held in the lower swingable sections 192 of the chute, by the lowermost coin sliding over a track 214. When the swingable section 192 of the coin chute has reached the dotted line position, the coins will fall therefrom and into a collection receptacle 215.

In FIG. 16 there are shown five coin chutes 190-192 corresponding to the coin operated switches in the partial circuit diagram of FIGS. ISA-B. The swingable lower sections 192 of the coin chutes are here interconnected by a bar 216 which is pivoted at 217 to eachof the coin chutes. The bar 216 has an ear or lug 218 thereon, which latter is secured to the bar by bolts or screws 219. The rod 207 from the electro-rnagnet 200 is connected to the lug 218 by having the pin 212 in the former received in an elongated slot 220 in the latter.

It will be understood that coin receptacles 215 (not shown) are provided beneath each of the swingable sections 192 of the coin chute in tions of the latter. I

As shown inthe partial circuit diagram of FIG. 17, the solenoid 200 for operating the swingable lower sections 192 of the'coin chutes is connected in parallel with the the coin dispensing posi- D.C. relay 175 by a conductor 221, which extends from one side of the winding of the electro-magnet 200 to a resistor R-S, the other side of the resistor being connected to the conductor 181 (FIG. 12), and by a conductor 222, which connects the other side of thewinding of the electro-magnet to the conductor174. A ca-' S-4 and 8-5 respectively,

pacitor 0-5 is shunted across the conductors 221 and 222. The DC. relay 175 is inherently a quick acting relay, in order to operate the electro-magnet 60 and for the hydraulic master cylinder 50 to open the valve 20 as soon as possible after the circuits including the starting or firing electrodes 165 of the electron discharge tubes T-l, T-2, T-3, T- 4 and T-S have been completed by closing the manually operate switches 8-1, 8-2, S3,

or their coin operated equivalents (FIG. 15). The electro-magnet 200 for shifting the lower sections 192 of the coin chutes to coin dispensing'position on the other hand, must be slow acting, since the coins must by their weight hold the

switch leaf springs

193 and 195 in engagement until the dispensing operation has been completed.

A time delay circuit for the electro-magnet is, therefore, provided. The time delay circuit is comprised by the resistor R-5 and the capacitor C-5. The electromagnet 200 will not draw its core 206 to central posivoltage is applied across the conductors 174 and 18 1,

' there being no back voltage across the capacitor, ourrent through the resistor R 5 will flow for the most part through the capacitor, Withvery little going through the winding of the electro-magnet 200. As the capacitor C-S builds up its charge, the back voltage across same increases to the point where it becomes equal to the voltage drop across the winding of the electr c-magnet 200. When the voltage drops across the capacitor C-5 and the winding of the electro-rnagnet 200 are equal,.the current flowing through the resistor R-l will divide with half going through the winding of the electro-magnet. The electro-magnet 200 will now be energized and will draw its core 206 centrally and through the rod 207 shift the lower sections 192 of the coin chutes to the coin dispensing position. I

Having now fully described my invention, what I claim as new and useful and desire to secure by Letters Patent of the United States is:

1. An apparatus for dispensing liquid fuel from a pump comprising a nozzle and a rotatable element the movement of which is a function of the cost of the fuel dispensed, a valve in said nozzle for controlling the flow of fuel through same, a hydraulic servo cylinder connected to said valve for operating same, an electro-magnet, a

electrical power supply through said switches to the anodes of the electron discharge tubes, branches from the cathodes of said electron discharge tube to said rotary cut-off switch, a circuit connection from the rotary cut-01f switch to the eleetro-magnet, and a circuit connection from the electro-magnet to the source of electrical power supply. 2. An apparatus for dispensing liquid fuel from a pump comprising a nozzle and a rotatable element the movement of which is a function of the cost of the fuel dispensed, a valve in said nozzle for controlling the flow of fuel through same, a hydraulic operating cylinder having a reciprocable piston for operating said valve, an electro-rnagnet having a reciprocable core connected to the piston of said hydraulic operating cylinder, a rotary cutoff switch connected to the rotatable element of said pump, a source of electrical power supply, a plurality of electron discharge tubes, an individual switch for both the anode and starting electrode of each electron discharge tube, a control circuit for said electro-magnet including branches from said source of electrical power supply through said switches to the anodes of the electron discharge tubes, branches from the cathodes of said electron discharge tubes to said rotary cut-off switch, a circuit connection from the rotary cut-off switch to the electro-magnet, and a circuit connection from the electromagnet to the source of electrical power supply.

3. An apparatus for dispensing liquid fuel from a pump comprising a nozzle and a rotatable element the movement of which is a function of the cost of the fuel dispensed, a valve in said nozzle for controlling the flow of fuel through same, a hydraulic servo cylinder having a reciprocable piston therein connected to said valve for operating the latter, a hydraulic operating cylinder having a reciprocable piston therein, a conduit between said hydraulic operating and servo cylinders, an electro-magnet having a reciprocable core connected to the piston of said hydraulic operating cylinder, a rotary cut-off switch connected to the rotatable element of said pump, a source of electrical power supply, a plurality of electron discharge tubes, an individual switch for both the anode and starting electrode of each electron discharge tube, a control circuit for said electro-magnet including branches from said source of electrical power supply through said switches to the anodes of the electron discharge tubes, branches from the cathodes of the electron discharge tubes to the rotary cut-E switch, a circuit connection from the rotary cut-off switch to the electron magnet, and a circuit connection from the electro-magnet to the source of electrical power supply.

4. An apparatus for dispensing liquid fuel from a fuel pump comprising a nozzle and a rotatable element the movement of which is a function of the cost of the fuel dispensed, a valve in said nozzle for controlling the flow of fuel through same, a hydraulic cylinder connected to said valve for operating the latter, an electro-magnet, a hydraulic operating cylinder having a reciprocable piston, a conduit between said hydraulic operating and hydraulic servo cylinders, an electro-magnet having a reciprocable core connected to the piston of said hydraulic operating cylinder, a rotary cut-off switch connected to the rotatable element of said pump, a plurality of electron discharge tubes, an individual switch for both the anode and starting electrode of each electron discharge tube, a control circuit for said electromagnet including branches from said source of electric power supply through said switches to the anodesof the electron discharge tubes, branches from the cathodes of the electron discharge tubes to the rotary cut-off switch, a circuit connection from the rotary cut-off switch to the electro-magnet, and a fluid pressure switch responsive to pressure within said nozzle connected between the electro-magnet and the source of electric power supply.

5. An apparatus for dispensing liquid fuel from a pump comprising a nozzle and a rotatable element the movement of which is a function of the cost of the fuel dispensed, a valve in said nozzle for controlling the flow of said fuel through same, an electro-magnet having a reciprocable core, a hydraulic transmission comprised by a hydraulic operating cylinder having a reciprocable piston connected to the core of said electro-magnet, a hydraulic servo cylinder having a reciprocable piston connected to said valve, a conduit between the hydraulic cylinders, a rotary cut-off switch connected to the rotatable element, a source of electrical power supply, a plurality of electron discharge tubes, an individual coin operated switch for both the anode and starting electrode of each electron tube, a control circuit for said electro-magnet including branches from said source of electrical power supply through said switches to the anodes of the electron discharge tubes, branches from the cathodes of the electron discharge tubes to said rotary cut-off switch, a circuit connection from the rotary cut-01f switch to the electro-magnet, and a circuit connection from the electromagnet to the source of electrical power supply.

6. An apparatus for dispensing liquid fuel from a pump comprising a nozzle and a rotatable element the movement of which is a function of the cost of the fuel dispensed, a valve in said nozzle for controlling the flow of fuel through same, an electromagnet having a reciprocable core, a hydraulic transmission comprised by a hydraulic operating cylinder having a reciprocable piston connected to the core of said electro-magnet, a hydraulic servo cylinder having a reciprocable piston connected to said valve, a conduit between the hydraulic cylinders, a rotary cut-off switch connected to the rotatable element of said pump, a source of electrical power supply, a plurality of electron discharge tubes, an individual switch for both the anode and the starting electrode of each electron discharge tube, a normally closed switch, a control circuit for said electro-magnet including branches from one side of said source of electrical power supply through said individual switches to the anodes of the electron discharge tubes, a branch from the latter side of the source of electrical power supply through said normally closed switch to the anodes of the electron discharge tubes, branches from the cathodes of the electron discharge tubes to said rotary cut-oft switch, a circuit connection from the rotary cut-off switch to the electromagnet, and a circuit connection from the electro-magnet to the other side of the source of electrical power supply.

7. An apparatus for dispensing liquid fuel from a pump comprising a nozzle and a rotatable element the movement of which is a function of the cost of the fuel dispensed, a valve in said nozzle for controlling the flow of fuel through same, a hydraulic servo cylinder having a reciprocable piston therein connected to said valve for operating the latter, a hydraulic operating cylinder having a reciprocable piston therein, a conduit between said hydraulic operating and servo cylinder, an electro-magnet having a reciprocable core connected to the piston of said hydraulic operating cylinder, a rotary cut-off switch comprised in part by a disc connected to the rotatable element of said pump and having arcuate conducting segments of varying lengths thereon, and brushes running over said conducting segments, a source of electrical power supply, a plurality of electron discharge tubes, an individual switch for both the anode and starting electrode of each electron discharge tube, a control circuit for said electro-magnet including branches from said source of electrical power supply through said switches to the anodes of the electron discharge tubes, branches from the cathodes of the electron discharge tubes to the brushes of the rotary cut-off switch, a circuit connection from the arcuate conducting segments of the rotary cut-off switch to the electro-magnet, and a circuit connection from the electro-magnet to the source of electrical power supply.

8. An apparatus for dispensing liquid fuel from a pump comprising a nozzle and a rotatable element the movement of which is a function of the cost of the fuel dispensed, a valve in said nozzle for controlling the flow of fuel through same, a hydraulic servo cylinder having a reciprocable piston therein connected to said valve for opening the latter, a hydraulic operating cylinder having a reciprocable piston therein, a conduit between said hydraulic operating and servo cylinders, an electromagnet having a reciprocable core connected to the piston of said hydraulic operating cylinder, a rotary cutoff switch connected to the rotatable element of said pump, ,a source of electrical power supply, a plurality of electron discharge tubes, an individual switch for both the anode and starting electrode of each electron discharge tube, a control circuit for said electromagnet in- 17 o 18 cluding branches from said source of electrical power References Cited in the file of this patent supply through said switches to the anodes of the electron discharge tubes, branches from the cathodes of the V UNITED STATES P N electron discharge tubes to the rotary cut-off switch, 8 2,150,324 Grunbaum Mar. 14, 1939 circuit connection from the rotary cut-off switch to the 5' 2,384,585 Alexander .Q. Sept. 11, 1945 electro-magnet, a shunt circuit connection from the cath- 2,557,242 Simpson June 19, 1951 ode of one of said electron discharge tubes to the electro v 2,777,555 Banning Jan. 15, 1957 magnet, and a circuit connection from the electro-mag- 2,828,782 Ripley Apr. 1, 1958 net to the source of electrical power supply.