Light-controlled fluid dispenser

[57] ABSTRACT

A fluid sensing device for controlling the dispensing of a liquid into a container in which a light beam is transmitted from a remote source to a predetermined location of fluid discharge and the light beam is reflected to a light responsive control circuit during fluid flow whereby upon light beam interruption or modification fluid flow may be terminated or re-initiated, manually or automatically.

Claims, 18 Drawing Figures

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Patented May 16, 1972

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Sheets-Sheet 1

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Patented May 16, 1972

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Sheets-Sheet 2

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INVENTORS

STANLEY C.CRANDALL

BILLY J.HARRIS

RICHARD L. NELSON

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137(b)

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FIG.IO

FIG.II

Patented May 16, 1972

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Sheets-Sheet 3

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FIG. 16

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FIG. 14

Fl G. 15

HO V. ac

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INVE NTORS

STANLEY C.CRANDALL BILLY J. H AR RIS

RICHARD L.NELSON

FIG.17

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LIGHT-CONTROLLED FLUID DISPENSER

This is a continuation of Ser. No. 790,963 filed Jan. 14, 1969, and now abandoned.

BACKGROUND, BRIEF SUMMARY, AND OBJECTIVES 5 OF THE INVENTION

The control of fluid flow into a tank or other receptacle has been achieved by various manually and automatically operated valves and nozzles depending upon the specific application or environment of the receptacle or tank to be filled. Substantial volumes of gasoline are dispensed to fill or fill partially fuel tanks in automobiles, vehicles, vessels and various types of movable and stationary storage tanks. Additionally, other petroleum products varying in viscosity are pumped into tanks in which visual or other tank capacity measuring devices are employed. Gasoline dispensing nozzles that are presently available employ various types of automatic tripping mechanisms that are generally dependent upon pressure responsive devices thereby freeing an attendant to perform other tasks for patrons without awaiting the filling of a tank at the filling location. Numerous types of automatic shut-off and safety nozzles that are presently available enable a service station attendant to supervise and perform simultaneously, while the gasoline tank is being filled, other services for patrons without observing continuously the gasoline pump computer when a gasoline tank is being filled. However, presently available automatic shut-off and safety nozzles are bulky, rather complex internally, and difficult to maintain, in addition to being quite costly. Significantly, presently available dispensing nozzles that are responsive to suction pressure fluctuations will be tripped automatically into the “off’ position when there is a backward surge of fluid that occurs rather frequently when an empty or partially filled tank is being filled rapidly due to air displacement from within the tank to the tank inlet which may cause fluid turbulence at the inlet resulting not only in tripping the nozzle automatically into the closed position but the overflow creates a dangerous fire hazard in the area where the overflow or spillage has occurred.

Numerous unsuccessful attempts have been made to utilize a low voltage sensing device in the fuel nozzle as a cut-off for fluid flow but the utilization of any electrical signals in the vicinity of the fluid dispensing nozzles has been rejected because it is not intrinsically safe particularly where highly flammable liquids are dispensed. Maximum precautionary measures are required to eliminate the occurrence of any static charge that may be developed in the dispensing apparatus and dispensing equipment must be grounded adequately to avoid fire hazards.

The introduction of self-service gasoline service stations with coin and bill-operated gasoline dispensers, and the use of remotely controlled pre-set gasoline dispensing apparatus which enables a customer to dispense gasoline to his own vehicle create added problems and hazards in service stations. Bulky, heavy and complex automatic, safety dispensing nozzles require trained personnel to operate them. Customers who experience a backward surge of gasoline during fill-up may not be aware of the cause of this phenomenon and may panic or complain to the management or may never return to the same self-service station fearful that similar experiences may occur.

The fluid sensing system of this invention employs an intrinsically safe light beam in proximity of the discharge of the dispensing nozzle with a light responsive control circuit for detecting fluid to terminate or monitor, within limits, fluid flow through the nozzle into a receiving tank. A flexible fiber optic element “pipes” or transmits light from a light source to the point of fluid discharge which discharge may be at a predetermined position relatively in a tank being filled. Another fiber optic element cooperates with the fiber optic element that receives the light from the light source to transmit a light beam from the fluid discharge position to a light responsive control circuit or receiving detector, generally at a remote location, to actuate the dispenser circuitry, within prescribed limits, either to terminate fluid flow or re-initiate fluid flow within a predetermined time interval in the event light conduction through the fiber optic elements is momentarily interrupted for a predetermined interval as during a backward surge of fluid.

The light-controlled fluid dispensing apparatus of this invention basically incorporates an intrinsically safe light beam for actuating and de-actuating the flow of fluid by sensing directly through a modification of the refractive index of a light transmission medium, such as a prism, the interruption or modification of light intensity to activate a control circuit when fluid impinges or “wets” the transmission medium which “feels” the fluid level in the receptacle to be filled while the light transmission medium is insensitive to the flow of fluid through the dispensing apparatus. By providing suitable holding circuits, “surges” and “topping” phenomena may be treated without complete fluid flow shutdown as such phenomena are momentarily only, however, in the event such phenomena are for sustained intervals, the system will be shutdown thereby obviating the necessity for repetitious manual resetting.

A unique adaptation of fiber optics, in addition to fluid detection or sensing when a receptacle is filled to a predetermined level, is the incorporation of a light beam in a first fiber optic system to initiate fluid flow by manual displacement of a nozzle lever through a predetermined position to transmit a beam of light to a light detector which will activate a circuit to commence fluid flow. The combination of a fiber optic system for actuating fluid flow and a second fiber optic system to sense fluid capacity in a receptacle to interrupt flow, momentarily and then re-initiate flow or terminate flow completely, presents a versatile and safe system that is most efficacious for dispensing fluids particularly those fluids that are highly flammable.

Briefly, the light-controlled fluid dispenser includes a fluid dispensing nozzle to which a fluid is supplied by a pump located at a remote location which may be actuated at the commencement of each pumping cycle with a light conducting fiber optic element leading from a light source to a light transmission element having a refractive index responsive and modifiable to fluid impingement and from the light transmission element to a light sensitive detector, such as a photocell, which detector controls by the light transmitted to the photocell the condition of a circuit for enabling fluid to flow. A second fiber optic system, preferably but not necessarily linked in the same circuit, is positioned for fluid flow actuation in a manually operable lever of a dispensing nozzle with fiber optic elements transmitting light from a light source to a displaceable transmission element before light transmission to a light detector for controlling an electrical ciccuit for actuating fluid flow. A current sustaining circuit is provided which re-initiates fluid flow when light conduction is momentarily interrupted or modified but re-established.

BRIEF DESCRIPTION OF DRAWINGS ILLUSTRATING PREFERRED EMBODIMENTS

Several preferred embodiments of this invention will be more readily understood from the following detailed drawings in which like characters of reference designate corresponding parts throughout the several views, and in which several of the figures are diagrammatic or schematic illustrations of the circuitry, and wherein:

FIG. 1 is a schematic illustration of a gasoline dispenser pump and fluid dispensing nozzle incorporating the invention;

FIG. 2 is a partial longitudinal sectional view, with portions removed, of a fluid dispensing nozzle and a schematic illustra70 tion of a light supply, light detecting and a light sensitive fluid control circuit incorporating one preferred embodiment of the invention;

FIG. 3 is a side elevational view of a modified dispensing nozzle containing fiber optic elements for controlling the in75 itiation and termination of fluid flow;

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FIG. 4 is an enlarged, partial, side elevational fragmentary sectional view of the dispensing nozzle trigger handle or lever of FIG. 1 in closed and partially open positions;

FIG. S is an enlarged, partial perspective and fragmentary sectional view of another modified embodiment of a nozzle 5 trigger handle or lever which contains a light conducting prism therein for cooperative alignment with light-conducting fiber optic elements;

FIG. 6 is a partial side elevational view of another modified nozzle trigger lever assembly for transmission of light between ¹ θ light-conducting members;

FIG. 7 is a partial plan view of FIG. 6;

FIG. 8 is an enlarged side view of a light conducting device for transmitting light between adjacent fiber optic elements of FIGS. 6 and 7; ¹⁵

FIG. 9 is a perspective and exploded view of the device of FIG. 8;

FIG. 10 is a transverse sectional view taken along the section line 10—10 of FIG. 8; 2θ

FIG. 11 is a transverse sectional view taken along the section line 11—11 of FIG. 8;

FIG. 12 is a partial right elevational view of the nozzle trigger and fiber optic elements of FIGS. 3 and 4;

FIG. 13 is a diagrammatic view of a modified fiber optic 25 control system utilizing a single fiber optic bundle in conjunction with a beam splitter;

Fig. 14 is an electrical diagram of a basic circuit arrangement for actuating a dispenser solenoid valve in response to a light pulse; 30

FIG. 15 is an alternative electrical diagram for controlling the actuation of a dispenser solenoid valve;

FIG. 16 is another alternative electrical diagram for controlling a solenoid valve of a dispensing system for reinitiating fluid flow; 35

FIG. 17 is still another electrical diagram for a light-responsive system for actuating a solenoid valve of a dispensing system for re-initiating fluid flow; arid

FIG. 18 is a further alternative electrical diagram for a lightresponsive control system to actuate a solenoid valve of a dispensing system.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

Referring to the drawings, and particularly to FIG. 1, there is illustrated, in outline form a gasoline dispensing pump housing 20 for enclosing the operating mechanisms and controls for dispensing gasoline which is stored in the storage tank 21 from which the fluid is withdrawn by the pump 22 that is 50 driven by motor 23 enabling the fluid to flow through pipe 24 and pumped through line 25 under pressure through the air separator 26. Fluid will flow through the meter 27 that is connected by output shaft 28 to the computer 29 which houses a cost variator (not shown) which will actuate and display ⁵⁵through suitable apertures 30 the volume and cost of the liquid dispensed for observation by a customer and service station attendant. The liquid will be discharged from the meter 27 through line 31 which is provided with a solenoid-operated valve 32 which may be actuated to initiate fluid flow manually °® through conventional mechanisms by an attendant or a customer or by actuation of one or more of the devices described herein. A control panel housing 33 mounted within housing 20 contains a light supply source, light detecting 55 means, and light responsive circuitry for controlling fluid flow as will be described hereafter. The discharge end 34 of valve 32 is connected to the line 35 which in turn is suitably connected to the flexible discharge hose 36 at the end of which is mounted a gasoline dispenser nozzle 37 with a discharge spout 70 38 which will be introduced into the fill spout of a tank to be filled. Nozzle 37 is provided with light-conducting means 39 for terminating fluid flow as will be described hereinafter.

There is illustrated in FIG. 2 a fluid-dispensing nozzle 40 that is connected to a flexible hose 41 which leads to a fuel- 75 dispensing pump with the hose 41 being connected to the nozzle through the threaded bushing 42. A lever guard 43 is secured to the nozzle housing 44 and pivotally supports the hand-pivotable lever 45 which pivots about the pivot pin 46 in the guard 43. A valve-actuating plunger 47 is slidably positioned in the packing gland boss 48 with the depending end 49 to be engaged by the plunger-engaging surface 50 on lever 45 with the helical spring 51 that encircles the depending end 49 of plunger 47 resiliency urging lever 45 out of engagement with plunger 47. The upper end 52 of plunger 47 engages with valve lever 53 that is pivotally supported on the valve lever pin 54 mounted in housing 44 with the valve lever 53 engaging the projecting end 55 of the valve assembly rod 56 which is urged by the encircling helical spring 57 into the seated position, as shown in FIG. 2, by having the valve disc 58 seated against the valve seat 59. The valve guide plate 60 is positioned in the valve housing to guide the displacement of the valve rod 56 therethrough and to provide a stationary support for spring 57 which extends longitudinally in the chamber 61 to engage with the rear of the slide washer 62. The valve guide plate 60 is provided with fluid flow apertures (not shown) through which the fluid may flow into chamber 61. Upon actuation of lever 45, plunger 47 will pivot valve lever 53 clockwise to displace valve rod 57 to the right against the action of spring 57 thereby opening the valve by unseating disc 57 against the seat 58 permitting the flow of fluid into the nozzle chamber 63 in which there is suitably supported a check valve 64 that is urged by helical spring 65 into the seated position, as shown in FIG. 2. Adequate fluid pressure of incoming fluid will displace check valve 64 from the seated position overcoming the force of spring 65 permitting flow of fluid through the nozzle into the discharge pipe 66 which is suitably fastened by the connecting bushing 67 to the housing 44.

A pair of flexible fiber optic light conducting elements 68 and 69 extend into the nozzle discharge pipe 66 and are suitably secured therein to minimize any fluid resistance to flow. The fiber optic elements may consist of a plurality of monofilaments arranged in a suitable sheath covering, and representative specimens No. 1410X and No. 1610X produced by du Pont have been suitable although other fiber optic elements capable of transmitting a light beam should be adequate for use in this environment provided the sheath is resistant to deterioration from exposure to gasoline and other types of fluides which may have a dissolving action. In particular, it may be advantageous to prevent exposure of the light guide sheath to gasoline in some applications to have the fiver optic elements supported within a separate external tube. The forward ends 70 of the light-conducting elements 68 and 69 are releasably securely fastened in a suitable recess formed in plastic or glass fiber optic retaining member 71 which is securely fastened to the interior of the nozzle pipe by the screws 72.

A light transmission prism member 73 is formed in the member 71 for cooperation with fiber optic elements 68 and 69 to receive a light signal from light conducting element 68 and to transmit it to element 69 provided the environment surrounding prism 73 has the proper refractive index. The prism 73 is suitably shielded from fluid flowing through the nozzle pipe 66 but the prism is exposed to fluid levels and surges through the wall aperture 74 of nozzle pipe 66 and is responsive to fluid that may rise or flow rearwardly about the discharge end 75 of the nozzle pipe 66. Discharge flow of fluid through the nozzle pipe 66 will not impinge of “wet” the light transmission prism member 73 which will be guarded by the member 71 from such flow. However, rearward or upward fluid flow as when a tank is filled or there is a surge of fluid rearwardly about the discharge end 75 of nozzle pipe 66, prism 73 may have fluid impinged thereon or become immersed through the aperture 74 so that the refractive index of the prism with respect to the surrounding medium may be altered thereby interrupting light conductance. The light transmission through the prism 73 will be modified when in contact with liquid because the relative index of refraction is different from that when the prism is surrounded by air.

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The fiber optic elements 68 and 69 extend rearwardly in pipe 66 and through the gland 76 for retention in the handle guard 43, and through the protective sleeve 77 which may be suitably secured to the flexible hose 41 into the dispenser housing 20 where the elements 68 and 69 will be introduced into the control panel housing 33. Suitably sealed within the control panel housing 33, and shown diagrammatically and schematically in the electrical circuit portion of FIG. 2, is a light supply source 80 to which current is supplied from a 110 volt AC line through the step-down transformer 81 to the fiber optic illuminating lamp 82 adjacent to which the end 83 of the light conducting fiber optic element 68 is supported to transmit a light beam from the lamp 83 to the prism 73 when the pump motor 23 of the dispenser 20 is actuated for each pumping cycle. However, it may be desirable to utilize a combination lamp and lens, in some instances, to focus a light beam on the end 83 of the light conducting element 68. The end 84 of the return light conducting fiber optic element 69 is positioned adjacent to the light sensor, photo conductive cell or photocell 85 to transmit to the photocell 85 any light transmitted to the fiber optic element 69 by prism 73. The solenoid coil 86 controls the actuation of the solenoid-operated valve 32 which, when properly conditioned, will permit fluid to flow when the pump 22 is driven by the motor 23.

Before commencement of a pumping cycle, contacts 87 and 88 are open and the solenoid valve 32 is closed since no current is supplied to the solenoid coil 86. At the commencement of a pumping cycle, the dispenser is turned on supplying current to the light supply source 80 and the photocell 85 will receive light reflected from prism 73 provided no fluid surrounds the prism to modify its refractive index with the light intensity thereby lowering or decreasing the resistance of the photocell 85. Upon actuating the reset push button 89 an electrical by-pass is provided around contacts 87 supplying current to the uni-junction 90 which will then trigger the silicon controlled rectifier (SCR) 91. Initially, current will flow in the circuit while the photocell 85 is illuminated and the reset 89 is actuated charging capacitor 92 to introduce a time delay before the emitter of the uni-junction 90 reaches its peak voltage and triggers the SCR. When the uni-junction 90 triggers, the capacitor 92 discharges through the resistor 93 and the gate of the SCR. Current flow to the gate of the SCR allows current to flow from the anode to the cathode of the SCR, and the SCR permits the rectified current to flow for all but a small initial 45 portion of a half wave. Current flow through the SCR is adequate to cause the relay coil 94 to close the contacts 87 and 88 with the resistor 95 such that the voltage across the base of the uni-junction 90 does not exceed a predetermined . ...-- ________r—-o value. The reset push button 89 may be released after contacts 50 ®^u*^d ^^{ow t0} R°^w directly at the nozzle through close. The solenoid valve 32 will open when the contacts ”^J close preconditioning the system for fluid delivery when the nozzle lever 45 is pivoted sufficiently to displace the valve lever 53 and the valve assembly rod 56 is urged to the right to . . - ___ _____ admit fluid into the nozzle. The relay coil 94 is used in con- 55 dispensing nozzle assembly 40 in which there is light-conductjunction with a diode 96 which is in parallel therewith to insure drop-out of the SCR at each half-cycle. There is a mechanical connection 97 between the relay coil 94 and the solenoid coil 86 through the contacts 88 and 87. The contacts adjacent the manual reset 89 are in direct line with the 60 ^{fluid flow u}P°^{n flow} immersion or impingement on the fightphotocell 85. Should the reset 89 be actuated when the j—--------- · — — photocell has insufficient light reflected thereon, there will be insufficient current passing through contacts 87 to activate the relay coil 94 and the solenoid coil 86. When adequate current __________________________ flows through the photocell 85, upon actuation of the reset 65 prism 111 that is suitably embedded protectively in the hub button, current will flow through the uni-junction transistor 90 ”-'· · to trigger the SCR, and current will then flow to the bridge rectifier 98 causing current to flow through the relay coil 94, closing contacts 88 to energize the solenoid 86.

When the refractive index about the prism 73 is altered, as 70 lever 113, as shown in FIG. 12, more clearly indicatesflie side when a liquid wets or engulfs or impinges on the prism 73, the '—^!J ' '' ” - · — photocell 85 will be darkened as the light intensity of the light beam returning through the element 69 is reduced and the resistance in the photocell is increased thereby decreasine current flow through the photocell causing the uni-junction to 75 mit reflection of the light beam therethrough, as the lever 113 cease to trigger the SCR. Diode 96 provides a path to collapse the flux field of the relay coil 94 in order to turn off the SCR. Current flow through the SCR drops thereby causing the relay coil 94 to open the contacts 87 and 88 which will then cause solenoid coil 86 to close solenoid valve 32 terminating fluid flow through the dispenser and nozzle by virtue of the light responsive circuit which will interrupt fluid flow upon fluid impingement on the light conducting element, and particularly the light transmission prism 73.

The system illustrated in FIG. 2 is adequate to perform automatic shut-off as well as topping fill of a tank. The feature of topping may be accomplished by resetting the push button 89 as many times as may be necessary in the event automatic shut-off occurs when fluid impinges upon the prism.

The manually reset light-responsive circuit included in FIG. 2 may be replaced by the automatic light-responsive circuit 100 of FIG. 18 while retaining the light supply source 80 and the light transmitting elements 68 and 69 while still utilizing a 110 volt AC supply so that when the dispenser is energized to turn the pump on, the photocell 101 receives light that is reflected from the prism 73 through the element 69 from the end 84 thereof and lowers the resistance of the photocell increasing current flow therethrough to the trigger 102 with the trigger current to the triac 103 causing current to flow through the triac thereby increasing current flow through the triac which amplifies current to flow to the solenoid coil 104 which will control the operation of solenoid valve 32. Solenoid valve 32 will open and allow fluid to flow when adequate current 30 flows to the solenoid coil 104, and liquid will be supplied to the nozzle when the nozzle lever 45 is actuated to open the nozzle valve. When the liquid lever engulfs prism 73 of liquid impinges thereon to modify the refractive index causing an interruption of modification of the intensity of the light return35 ing to the photocell 101, the increase in resistance of the photocell will drop the current flow through the photocell and the trigger 101 and 102 causing the triac 103 to stop conducting de-energizing solenoid coil 104 which will then close solenoid valve 32 thereby terminating fluid flow from the 40 dispenser to the nozzle. The system illustrated in FIG. 18 is capable of performing automatic shut-off as well as topping without the necessity of manual reset as required in the light responsive control circuit of FIG. 2.

Heretofore there has been described a light-controlled fluid dispenser in which a light-detecting circuit is responsive to light intensity in order to interrupt fluid flow. It has been found desirable to utilize light-conducting members in combination with such light-responsive means for interrupting which the fluid is dispensed as will be described in the several illustrated embodiments in FIGS. 3 through 12. There is illustrated in FIGS. 3 and 4 a fluid dispensing nozzle 106 that is substantially comparable in construction to the fluid ing fiber optic elements 107 for transmitting a beam of light from a remote light source to a light transmission member 108 within the discharge pipe 109 and a return for reflected light to a photocell of the type heretofore described for interrupting conducting transmission member 108. The combination⁵ or auxiliary system for initiating fluid flow incorporates light receiving and reflecting fiber optic elements 110 which are employed in combination with a light transmission member or il! of the nozzle hand actuating lever 113 that is pivotally mounted on the pivot pin 114 to the depending hand guard 115 for the lever 113. A light transmission prism 111 which is shown protectively embedded in the boss 112 of the hand by-side relationship of the fiber optic elements 110α and HOfc in which light from a remote light source will be conducted through the element 110α to the prism 111 and, when coincidence of path of light may occur, as when prism 111 will per3,662,924 is pivoted through its arc of displacement, the reflected light from element 110* will be detected at a photocell, as will be described. A momentary pulse of light is adequate to initiate circuit operation when a proper combination of photodetector circuits is utilized. In FIGS. 3,4 and 12, the light pulse for initiating circuit operation and commencing fluid flow will occur as the lever 113 is pivoted through approximately 10° to 15° from the full-line off position of the lever shown in FIG. 4. A light pulse will occur when the lever 113 reaches the broken line position in FIG. 4, and as shown in FIG. 12, but the lever 113 is only partially depressed in its displacement to urge the valve open through elevation of the plunger 116.

A description of alternative embodiments for initiating a light pulse will be described briefly before describing in detail the electrical circuits for initiating fluid flow and fluid interruption. In FIG. 5, the lever guard 117 cooperatively and pivotally receives the lever 118 mounted on the pivot pin 119 about which pin 119 a shutter 120 having an aperture 121 is yieldably biased by the spring 122 in a clockwise direction against the limiting stop 123 which is secured to the guard 117 at one end 124 thereof. Prism 125 is protectively embedded in the hub 126 of the lever 118 comparable to that shown in FIG. 12 with the light-conducting elements 110α and 110* being suitably supported in spaced relation to the surface of shutter 120 and out of contact therewith. A shutter displacing and release lever 127 is pivotally mounted intermediate its length to the boss 126 with the free end 128 engaging the shutter 120 and the other end 129 being connected to the spring 130 with _____ _{llulu lluw U1 ln} the other end of the spring being connected to the lever ₃₀ belowtheTighttrMsmisrionmember mounted spring engaging stud 131. As the lever 118 is pivoted counterclockwise, shutter 120 will be displaced counterclockwise against the action of spring 122 which engages the upturned lip 132 of shutter 120. When the shutter aperture 121 is in registry with the terminal ends of the elements 110α 35 and 110*, the prism 125 will also be in registry with the aperture 121 and light transmitted through element 110α will be reflected through the prism 125 to element 110* momentarily since the shutter engaging and activating member 128 will become disengaged with the shutter by virtue of the eccentric mounting thereof enabling spring 122 to pivot shutter 120 in a clockwise direction after a light pulse has been reflected back to a photocell through light conducting element 110*. Lever 118 may continue to be displaced counterclockwise throughout fluid flow and until fluid is impinged upon the light ⁴⁵conducting prism 108 to interrupt the light beam and thereby interrupt fluid flow as heretofore described. In the event of lever release or fluid flow interruption, lever 118 may be recycled subject to fluid level in the nozzle at the prism or fluid impingement.

In FIGS. 6 through 11, there is illustrated another embodiment for providing a light pulse to initiate fluid flow in which the lever hand guard 135 retains a displaceable prism-supporting housing 136 into which housing light conducting elements 137 are supported for transmitting and reflecting a light beam upon communication with a light-conducting prism portion 138 which is provided in the displaceable cylinder 139. The housing sleeve 140 is provided with light-conducting elementreceiving openings 141. The end 142 of sleeve 140 is closed for cooperatively receiving the coil spring 143 at the base above which the plastic or glass cylinder 144 is positioned for displacement within limits, and above which cylinder the contact button 145 is seated for projection through the opening 146 provided in the closure cap 147, as shown in FIG. 9 in the 65 exploded condition. The assemblage shown in FIG. 8 depicts the light-conducting elements 137 in the non-conductive position, also shown in FIG. 11 wherein the light-conducting elements 137α and 137* are presented to a non-conducting member 148 in cylinder 144 at one extremity of the light ele- 70 ment receiving recess 149. Upon displacement of the button 145 downwardly, as shown in FIG. 8 but displaced to achieve the orientation as shown in FIG. 10, the elements 137 will be seated against the opposite side of the recess 149 in the plane of prism 138 to transmit light therethrough for reflection 75 through element 137b. The lever 150 is pivotally supported to the guard 135 through the pivot pin 151, and a button-actuating cam 152 is mounted on the pivot pin 151 for pivotable movement with the lever 150, within limits. A leaf spring 153 is secured at one end to the lever 150 through the stud 154 with the other end 155 being cooperatively seated against the cam projection 156. Coil spring 157 is fastened at one end to the spring-supporting stud 158 mounted on the lever 150 with the other end of the spring being fastened to the cam 152 by the spring-fastening stud 159. Spring 157 is trained about the spring guide washer 160 which is contiguous to cam 152 and mounted on the pin 151. A button-receiving recess 161 is provided on cam 152 for cooperatively seating against button 145 as shown in FIGS. 6 and 7, Upon counterclockwise pivoting of lever 150, spring 153 urges cam 152 to rotate in a counterclockwise direction. Cam 152 will urge button 145 into housing 136 against the action of spring 143 displacing cylinder 144 sufficiently to place the prism 138 in light-transmitting communication with elements 137α and 137*. Upon further rotation of lever 150, spring 155 will pass over projection 156 on cam 152 thereby restoring button 145 to the projected position as shown in FIGS. 6 and 7. Spring 157 will endeavor to restore the cam 152 to the position shown in FIG. 6 after a light pulse has passed through prism 138 to initiate circuit operation. In the event of fluid level rise to interrupt flow or from fluid impingement through the light-conducting member 108, lever 150 may be released to its starting position and recycled to reinitiate fluid flow in the event the fluid level is

A combination electrical circuit for responding to the level of fluid in a tank and for initiating fluid flow is illustrated in FIG. 14 in which power is supplied through a 110 volt A.C. line and in which a light supply source comparable to light source 80 shown in FIG. 2 is utilized preferably for supplying light beam not only to the fluid level light-conducting elements 107 but also the light-conducting elements 110 or 137 shown in FIGS. 3, 4, 5, 6, 7, 8, 10, 11 and 12, although a separate light source may be utilized, if desired. The photocell 165 will receive reflected light from the light transmission prism 108 through a light conducting element comparable to element 69 in FIG. 2 when the liquid level is below the prism 108 in FIG. 3 thereby reducing the resistance in photodetector 165 to energize coil 166. Photocell 165 will permit the instant passage of a light pulse to reduce the resistance in photocell 165 when the light transmission prisms 111 in FIGS. 3, 4 and 12, or the prism 125 in FIG. 5, or the prism 138 in FIGS. 6, 7 and 8, permit the transmission of a light beam to increase current flow with the associated coil 168. When the coils 166 and 168 are energized, the contacts 169 and 170 are closed in response to the currents passing through the coils 166 and 168 thereby energizing the solenoid valve coil 171 which will actuate solenoid valve 32 into the open position thereby initiating fluid flow. When fluid impinges or touches the light-conducting prism 108 (FIG. 3) 125 (FIG. 5) 138 (FIG. 6 and 8), the refractive index thereof changes and light passage through the prism is reduced which decreases the illumination at the resistive photocell 165 thereby greatly increasing the resistance thereof to deenergize coil 168 causing contacts 170 to open. Deenergization of the solenoid valve coil 177 will occur upon separation of contacts 170 terminating fluid flow as the solenoid valve 32 will close. It will be readily apparent that in those instances when a solenoid coil energizes or deenergizes the solenoid valve 32, the windings of the pump motor may be substituted, if desired. The cycle may be reinitiated by recycling the hand lever to supply an additional light pulse provided the liquid level has been lowered to permit light conduction through the light transmission prism 108.

It has been found desirable to provide a “capping-off” or “topping” action, that is, to supply additional liquid to the receiving receptacle after a surge of liquid may deactivate the dispensing operation provided the surge is only momentary thereby reinitiating fluid flow automatically until the level of liquid immerses the light conducting prism to alter or modify

3,6 the refractive index thereof. There is illustrated in FIG. 15 an electrical circuit capable of reinitiating fluid flow automatically to provide the desirable “capping-off” feature. In this circuit, the photocell 175 will receive light reflected back from a light conducting element in communication with the fluid level detecting prism such as 108 in FIG. 3. Photocell 176 will respond to the momentary light pulse provided by the nozzle lever action heretofore described in conjunction with the embodiment shown in FIGS. 3,5 and 6, wherein there will be a decrease in resistance upon reception of light reflected to photocell 176 causing current to flow through coil 177, assuming photocell 175 is conducting, thereby closing contacts 178 and establishing a circuit through coils 179 and 180. The contacts 181 associated with solenoid coil 182 are closed when a circuit is established so that solenoid valve 32 may be opened (or a pump motor may be energized) to initiate fluid flow. Contacts 178 are open shortly after being closed as the momentary light pulse will lower the resistance of photocell 176 momentarily only. Current will continue to flow through coils 179 and 180 by virtue of the closed contacts 183 which are held by current flowing through coil 179. A capacitor 184, in parallel with coils 179 and 180, is charged to the voltage across coils 179 and 180. When the refractive index of the light-conducting prism 108 is changed or modified due to fluid impingement or envelopment, the resistance of photocell 175 increases due to a decrease in the light reflection intensity and the current is reduced through coil 180 thereby opening contacts 181 which in turn will cause deenergization of solenoid coil 182 closing solenoid valve 32 to terminate fluid flow.

The “capping-off” action or “topping” will occur when a liquid surge envelops or impinges upon the prism 108 momentarily which will terminate fluid flow. However, the capacitor 184 will discharge over a predetermined interval of time through coil 179 to maintain the coil energized which will hold contacts 183 closed thereby providing a circuit for current flow through coils 180 and 179 and the photocell 175 in the event photocell 175 becomes reilluminated if the liquid level subsides in the vicinity of prism 108. In this event, provided the capacitor 184 has not fully discharged, within the predetermined interval to reestablish current flow upon re-illumination of photocell 175, thus, within the time required for the capacitor 184 to discharge through coil 179 to a voltage level sufficient to allow contacts 183 to open, the system may be reinitiated to permit fluid to flow provided the interval of ⁴³time is not for any sustained period beyond the discharge momentary interval of the capacitor 184. The contacts will remain open and the circuit deenergized unless photocell 175 is again momentarily illuminated to re-initiate the operating cycle. The diode 184 is positioned in series with coil 179 and the capacitor to prevent the capacitor from discharging through coil 180. It is desirable for the capacitor 184 to discharge for approximately a two-second interval during which time fluid flow may be re-initiated upon liquid level subsidence with attendant re-illumination at photocell 175. Dispensing of the fluid will then continue until fluid level rises to engulf the prism 108 at which time delivery will be terminated. This cycle can be repeated a number of times until the tank is completely filled or the liquid remains about the prism 108 for a duration of time necessary for the capacitor 184 to discharge fully through coil 179 to a voltage below that of the holding current required for the coil.

An alternative circuit combination for interrupting fluid flow upon liquid level detection and fluid flow initiation system is shown in FIG. 16 with the fluid level sensitive photocell 187 and the fluid flow initiation photocell 188 being in parallel to each other and to each photocell a light beam from a light-conducting element is reflected as in FIG. 15. When a dispenser nozzle 106 has a light-conducting prism 108 above the fluid level, photocell 187 will conduct and transmit a signal to activate relay coil 189 closing contact 190. Should prism 108 be immersed in fluid or fluid impinged thereon, the refractive index will be altered and photocell 187 will cease to emit any signal and contacts 190 will remain open. Upon ac62,924 tuation of the hand lever 113 (FIG. 3) or 118 (FIG. 5) or 150 (FIG. 6), a light pulse will energize photocell 188 and, provided photocell 187 is preconditioned to conduct a signal, current will flow and the uni-junction 191 will trigger the SCR ⁵ 192 to amplify current flow to the solenoid valve coil 193 which is directly in the line current with resistor 194 being mounted in parallel with coil 193 to prevent excess current from passing to the coil 193. Capacitor 195 is in parallel with 10 ^coil I®®’ with diode 196, which capacitor will maintain current flow in the circuit for a predetermined time interval after photocell 187 ceases to conduct when fluid impinges or immerses prism 108. The resistance in photocell 187 to conduct will increase with diminished light reflection causing ₁₅ the uni-junction 191 to cease to trigger the SCR 192 thereby terminating current flow adequate to retain the solenoid valve 32 in the open condition. In the event of a surge of fluid or rise in liquid level about prism 108, fluid flow will terminate but capacitor 195 will discharge and maintain the contacts 190 in 2q closed condition for a predetermined time interval but the unijunction 191 will cease to trigger the SCR 192. In the event the fluid level is maintained about the prism 108, the system will shut down. However, in the event the fluid level about the prism 108 subsides, photocell 187 will become reactivated or 25 conductive without recycling the hand lever so that current will be restored to the coil 193 and the uni-junction 191 will recommence triggering the SCR 192 to reinitiate current flow energizing solenoid coil 193 to open valve 32 causing fluid to flow again. The time interval for a surge of liquid to subside 30 may vary but the capacitor 195 will be able to retain the circuit for approximately 2 seconds. In the event the fluid surge does not subside within this predetermined interval of capacitor discharge, the system will shut down and recycling will be necessary by actuating the nozzle hand lever.

Another alternative electrical circuit for use in the combination of fluid level detection and flow interruption, and fluid flow initiation, is shown in FIG. 17 for reinitiating fluid flow in the event of a fluid surge with the photocell 197 being connected to receive reflected light from a nozzle lever to in40 itiate fluid flow as heretofore described provided an associated photocell 198 will conduct current flow received from reflected light from a light-conducting element when the nozzle prism 108 is not immersed in fluid and the refractive index in light remains unaltered. Contacts 199 will be closed when sufficient current flows in the circuit to the uni-junction 200 which will amplify current flow to the coil relay 201 that is connected in parallel with capacitor 202. Relay coil 203 is connected to the contacts 204 leading to the solenoid coil 205 ₅0 that is connected across the 110 volt AC line. Fluid flow will be initiated upon nozzle lever actuation by passing a light pulse to photocell 197. When prism 108 is impinged with fluid or the fluid level rises to submerge the prism 108, photocell 198 ceases to conduct and there is insufficient base current 55 from the uni-junction 200 to retain the contacts 204 in the coil relay 203. When the resistance in photocell 198 increases above a certain point, current will cease to flow and then capacitor 202 will discharge in order to maintain contacts 199 closed for a predetermined time interval. When photocell 198 60 ceases to conduct, solenoid coil 205 will be deenergized when contacts 204 open thereby terminating fluid flow. However, within the predetermined time interval of capacitor 202 discharge, should photocell 198 receive light it will recommence current flow automatically without recycling provided 65 the photocell 198 recommences conducting prior to full discharge of capacitor 202. In the event photocell 198 does not recommence activation of the circuit, solenoid coil 205 will remain deenergized and the entire system will shut down.

It will be apparent that the disclosed light-controlled fluid 70 dispenser utilizes light-conducting members that are associated with a fluid-dispensing nozzle in which a light supply source will Aluminate the light-conducting members which wdl be used in combination with a light-sensitive member having a refractive index which will vary in air and liquid to inter75 rupt a light signal to actuate a light-detecting means employed

3,662,924 in combination with an electrical circuit responsive to the light-detecting means to interrupt fluid flow in the fluid dispensing member and to reinitiate flow depending upon the fluid level sensed. Manual as well as automatic fluid flow reinitiation may occur depending upon the circuitry employed.

It has been found desirable to reduce the size and number of the fiber optic elements by endeavoring to employ the same fiber optic elements for two-way light transmission as shown in FIG. 13. The fiber optic light-conducting bundle 207 includes one or more continuous monofilaments of light-conducting units which will transmit light from the light source 208 through a suitably coated inclined surface 209 supported by the member 210 so that light will be transmitted through the filaments 211 to the light-reversing prism 212 which will be exposed to a fluid being filled in a receptacle. Light will be reflected by prism 212 provided the refractive index remains unaltered through the filaments 211 to the inclined surface 209 which will reflect the light downwardly to a light sensor or photocell 213 which will be sufficiently sensitive to receive the reflected light which passes through the same fiber optic elements in both directions. It is contemplated that prism 212 may be inserted in the nozzle in place of prism 108 as well as in the hand lever positioned prisms for utilizing the single fiber 25 optic element bundle with the inclined surface 209 being located at a remote position to pick up reflected light. The light beam splitter member 209 may have one surface suitably mirrored to permit light to pass therethrough from a light source while the mirrored surface will reflect the light at right 30 angles downwardly to the photocell 213.

It is further contemplated that the prisms positioned in the nozzle pipe be suitably guarded to prevent fluid impingement during fluid flow through the nozzle that may impair proper medium is the “fluid.”