U.S. patent number 3,662,924 [Application Number 05/119,351] was granted by the patent office on 1972-05-16 for light-controlled fluid dispenser.
This patent grant is currently assigned to Gilbert & Barker Manufacturing Company. Invention is credited to Stanley C. Crandall, Billy J. Harris, Richard L. Nelson.
United States Patent |
3,662,924 |
Crandall , et al. |
May 16, 1972 |
LIGHT-CONTROLLED FLUID DISPENSER
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.
Inventors: |
Crandall; Stanley C.
(Greensboro, NC), Harris; Billy J. (Greensboro, NC),
Nelson; Richard L. (Greensboro, NC) |
Assignee: |
Gilbert & Barker Manufacturing
Company (New York, NY)
|
Family
ID: |
22383927 |
Appl.
No.: |
05/119,351 |
Filed: |
February 26, 1971 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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790963 |
Jan 14, 1969 |
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Current U.S.
Class: |
222/64; 141/192;
141/198 |
Current CPC
Class: |
B67D
7/465 (20130101); B67D 7/46 (20130101) |
Current International
Class: |
B67D
5/37 (20060101); B67D 5/372 (20060101); B67d
005/08 () |
Field of
Search: |
;222/64,66 ;350/96R,96B
;137/93 ;141/208,218,219,192,195 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Tollberg; Stanley H.
Parent Case Text
This is a continuation of Ser. No. 790,963 filed Jan. 14, 1969, and
now abandoned.
Claims
We claim:
1. A light-controlled fluid dispenser comprising; a
fluid-dispensing means including a nozzle for discharging fluid
from one end thereof, light-conducting means associated with said
fluid-dispensing means and having at least a portion thereof
located within said nozzle, a light supply associated with said
light-conducting means, light-detecting means for receiving light
from said light-conducting means, said light supply and said
light-detecting means being positioned remote from said
fluid-dispensing means and means responsive to said light-detecting
means to interrupt fluid flow in said fluid-dispensing means upon
fluid impingement on said light-conducting means.
2. A light-controlled fluid dispenser as claimed in claim 1, and
means within said nozzle shielding said light-conducting means from
fluid flow through said fluid-dispensing means until fluid rises in
the direction opposite from fluid flow to a predetermined level to
modify or interrupt light conduction in said light-conducting
means.
3. A light-controlled fluid dispenser as claimed in claim 1, said
light-conducting means including a first fiber optic element to
receive light from said light supply, means having a refractive
index responsive to fluid impingement for receiving light from said
first fiber optic element, and a second fiber optic element to
return light from said refractive index responsive means to said
light-detecting means unless said refractive index responsive means
is impinged or immersed in fluid to modify or interrupt the return
of light in said second fiber optic element.
4. A light-controlled fluid dispenser as claimed in claim 1, said
fluid-dispensing means nozzle having a fluid discharge end, said
light-conducting means having a first fiber optic element having
one end proximate said light supply and the other end proximate the
discharge end of said nozzle, a light-conductive prism positioned
adjacent said other end of said fiber optic element in said
discharge end of said nozzle, said prism being sensitive to liquid
impingement to alter the refractive index thereof, and a second
fiber optic element extending from said prism to said
light-detecting means to conduct light from said prism to said
light-detecting means.
5. A light-controlled fluid dispenser as claimed in claim 1, said
fluid-dispensing means including a gasoline pump for discharging
gasoline from one end of said nozzle, a solenoid-operated fluid
control valve actuable by said light-detecting responsive means to
control fluid flow through said nozzle, said light-conducting means
including a first fiber optic element extending from said light
supply to a position proximate the discharge of fluid from said
nozzle, a light-conductive prism shielded from fluid flow through
said nozzle positioned to receive light from said first fiber optic
element and sensitive to liquid impingement to alter the refractive
index of said prism, and a second fiber optic element to receive
light from said prism for transmission of light to said
light-detecting means to actuate said light-detecting responsive
means to control fluid flow in said fluid-dispensing means.
6. A light-controlled fluid dispenser as claimed in claim 1, and
means for re-initiating fluid flow after light modification or
interruption for a predetermined momentary interval through said
light-conducting means to said means responsive to said
light-detecting means whereby upon a subsidence of a surge of fluid
interrupting light conduction and light restoration to said
light-detecting means fluid flow is re-initiated until light
conductance is modified or interrupted for a sustained
predetermined interval that is longer than said momentary
interval.
7. A light-controlled fluid dispenser as claimed in claim 1, said
fluid-dispensing nozzle having manually operable valve means for
actuating fluid to flow in said fluid-dispensing means.
8. A light-controlled fluid dispenser as claimed in claim 1, said
fluid dispensing nozzle means having a manually operable
displaceable lever for initiating fluid flow, light-conducting
means associated with said lever receiving light from said light
supply and conducting light therefrom upon lever actuation, and
light detecting responsive means controlling the initiation of
fluid flow in said fluid dispensing means through said nozzle.
9. A light-controlled fluid dispenser as claimed in claim 8, said
light-conducting means associated with said lever having a first
fiber optic element, a second fiber optic element, and light
transmission means between said first and second elements whereby
displacement of said lever actuates said light-detecting responsive
means to initiate fluid flow in said fluid-dispensing means, said
means responsive to said light-detecting means having means for
re-initiating fluid flow upon cessation thereof from fluid
impingement upon said light transmission means within a
predetermined momentary interval unless light conductance is
interrupted for a sustained predetermined interval longer than said
momentary interval.
10. A light-controlled fluid dispenser as claimed in claim 1; said
fluid-dispensing means further including a solenoid actuated valve,
said solenoid-actuated valve and said nozzle guiding fluid flow
from a remote location into a receptacle, said light-conducting
means having a first fiber optic element having one end proximate
said light supply and the other end proximate the discharge end of
said nozzle, a light conductive prism positioned adjacent said
other end of said fiber optic element in said discharge end of said
nozzle sensitive to liquid impingement to alter the refractive
index of said prism, a second optic element proximate said prism to
said light-detecting means to conduct light from said prism to said
light-detecting means whereby upon fluid impingement on said prism
for a sustained interval said light-detecting means will
de-activate said solenoid valve to terminate fluid flow, a
manually-operable lever in said fluid-dispensing means displaceable
between limits, a first fiber optic element associated with said
lever receiving light from said light supply, a second fiber optic
element in juxtaposition to said first fiber optic element, a light
transmission means for transmitting light from said first fiber
optic element to said second fiber optic element at a predetermined
position of lever displacement, a light-detecting means for
receiving light from said second fiber optic element to actuate
said solenoid-actuated valve to initiate fluid flow to said nozzle,
means for sustaining current flow in said light-detecting
responsive means for a predetermined momentary interval upon fluid
impingement on said prism in said nozzle unless light conductance
is interrupted for a sustained predetermined interval longer than
said momentary interval to terminate current flow and de-actuate
said solenoid valve.
11. A light-controlled fluid dispenser as claimed in claim 1, said
light-conducting means including a fiber optic, light-conducting
member, means for passing light from said light supply therethrough
to said fiber optic, light-conducting member, means for reflecting
light through said fiber optic, light-conducting member, and means
for deflecting said reflected light from said fiber optic
light-conducting member to said light-detecting means.
Description
BACKGROUND, BRIEF SUMMARY, AND OBJECTIVES 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 illustration
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 initiation and
termination of fluid flow;
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. 5 is an enlarged, partial perspective and fragmentary
sectional view of another modified embodiment of a nozzle 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
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;
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;
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 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;
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;
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; and
FIG. 18 is a further alternative electrical diagram for a
light-responsive 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 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 through 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 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 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-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 resiliently 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.
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 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 value. The reset push button 89 may be
released after contacts 87 close. The solenoid valve 32 will open
when the contacts 88 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 conjunction 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 87 adjacent
the manual reset 89 are in direct line with the photocell 85.
Should the reset 89 be actuated when the 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 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 when a
liquid wets or engulfs or impinges on the prism 73, the 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 decreasing current flow through
the photocell causing the uni-junction to 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 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
returning 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 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 fluid flow to initiate
fluid flow directly at the nozzle through 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 dispensing nozzle assembly
40 in which there is light-conducting 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 fluid flow upon flow immersion or impingement on
the light-conducting transmission member 108. The combination 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 prism
111 that is suitably embedded protectively in the hub 112 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 lever 113, as shown in FIG. 12, more
clearly indicates the side-by-side relationship of the fiber optic
elements 110a and 110b in which light from a remote light source
will be conducted through the element 110a to the prism 111 and,
when coincidence of path of light may occur, as when prism 111 will
permit reflection of the light beam therethrough, as the lever 113
is pivoted through its arc of displacement, the reflected light
from element 110b 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.degree. to
15.degree. 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 110a and 110b 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 the other end of the spring being connected
to the lever 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 110a and 110b,
the prism 125 will also be in registry with the aperture 121 and
light transmitted through element 110a will be reflected through
the prism 125 to element 110b 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 110b. Lever 118 may continue to be displaced
counterclockwise throughout fluid flow and until fluid is impinged
upon the light conducting 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 element-receiving 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
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 137a and
137b are presented to a non-conducting member 148 in cylinder 144
at one extremity of the light element 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 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 137a and 137b. 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 below the light
transmission member.
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 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 time 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 actuation 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 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 relay coil 189, and
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 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 closed condition for a predetermined time
interval but the uni-junction 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 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 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 initiate 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 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 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 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 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
dispenser utilizes light-conducting members that are associated
with a fluid-dispensing nozzle in which a light supply source will
illuminate the light-conducting members which will be used in
combination with a light-sensitive member having a refractive index
which will vary in air and liquid to interrupt a light signal to
actuate a light-detecting means employed 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
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 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 functioning of the
system. It is intended that where the term "fluid" is used
throughout the specification and claims a liquid medium is the
"fluid."
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