Add-on liquid overflow shut-off valve for tank

An add-on liquid overflow shut-off valve including a valve body, a float and an arm connecting the float to the body that is insertable in fully assembled form through a standard tank lid opening, and further including a flanged end on the valve body for engagement outside and above the rim of the opening and threads associated therewith to engage the periphery of the opening to anchor the body inside the interior of the tank and at the top thereof, pneumatic openings formed in the top flanged end in spaced-apart relation for connection respectively to a pressurized pneumatic source and a pneumatic-driven liquid pump arranged to pump liquid into the tank through another opening in the tank, first and second pneumatic passageways formed interior the body extending from the openings, a third pneumatic passageway formed in the body for interconnecting the first and second passageways, and a shaft pivotally received in the body, having a fourth pneumatic passageway formed therethrough for pneumatic alignment with the third pneumatic passageway when the liquid is below a predetermined level in the drum, the shaft having one end thereof exiting the valve body for connection through an extended arm to a float for causing rotation of the shaft as a function of the level of liquid in the tank and to allow pneumatic power to drive the pump and continue to deliver liquid into the tank and then to rotate into a position shutting off the pneumatic power to the pump when the level of the liquid reaches the predetermined level.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention pertains to the technology of storage of liquids, including 
toxic liquids. More particularly, it pertains to a shut-off valve for use 
in pumping liquid into a storage vessel that shuts off the delivery pump 
when the tank becomes full. 
2. Description of the Prior Art 
Proper storage and handling of waste liquids, especially toxic liquids, has 
become very important because of the discovery that so many of them have 
been found to cause cancer and other serious diseases. Liquids that 
previously were treated as mere waste are now known to be highly dangerous 
to humans, as well as to the environment, and require careful and safe 
storage until they can be rendered harmless by further processing or 
become benign by passage of time. 
The need to store these materials in leak-proof containers is now required 
by such government agencies as OSHA (Occupational Health and Safety 
Agency), the National Health Institute and others. A wide array of storage 
containers may be used, from small 1 and 2-gallon cans to large tanks, 
both underground and transportable. A container widely used in this 
situation is the standard 55-gallon drum; it is quite plentiful and its 
thick metal walls will safely store most materials. 
These 55-gallon drums, along with other such containers, contain a 
standard, 2-inch diameter threaded aperture in the lid known as a "bung 
hole" that can be used for pouring or pumping liquid into the drum as well 
as to have test probes inserted thereinto for the purpose of determining 
various attributes of the stored liquid. Other openings are also formed in 
the top or lid of the drum. This same bung-hole type opening is also found 
in virtually all storage tanks from the very small to the extremely large. 
The rim of the bung hole usually contains a series of threads to accept a 
threaded plug known as a "bung". 
One disadvantage in the use of storage tanks and drums, including the 
55-gallon drum, is that they are so well sealed no light can penetrate the 
interior. In many cases no incandescent lamp can be safely used to aid one 
looking inside because the stored contents are either poisonous or highly 
combustible. Often the drum is pumped completely full of liquid and the 
pump is not shut down soon enough with the result that liquid spills out 
of the lid openings over the sides and onto the ground or other supporting 
surface to cause the toxic condition to become a problem all over again. 
Positioning a person to continually observe the level of fullness in the 
tanks raises labor costs and places him or her in a dangerous position 
near the toxic material. 
A recent proposed change to the Uniform Fire Code states as follows: 
"2-4.5 Piping and Ancillary Equipment 2-4.5.1 Means shall be provided for 
determining the liquid level in each tank and this means shall be 
accessible to the delivery operator. Provisions shall be made either to 
automatically stop the delivery of fuel to the tank when the liquid level 
in the tank reaches 95% of capacity or to sound an audible alarm when the 
liquid level in the tank reaches 90% of capacity." 
The prior art has tried to deal with the problem of shutting off the flow 
of liquid into a tank, when the level reaches the uppermost safe point, 
but such attempts have not met with unbridled success. For instance, U.S. 
Pat. Nos. 559,555; 609,544; 968,362; 1,150,342; 1,427,793; 1,629,545; 
1,188,535; 2,847,025; 4,493,337; and German Patent 2,148,868, as well as 
British Patents 20,399 and 828,125 all show float-operated shut-off valves 
that are mountable on a tank or boiler. However, in none of these devices 
may they be fully insertable through one opening, i.e., the floats are so 
large that they must be put inside the tank or boiler through a separate 
opening from that through which any other portion of the shut-off valve is 
inserted. In other of these devices, the liquid actually passes through 
the valve thereby requiring the valve to be removed, disassembled and 
cleaned before it can be used with other liquids. 
Without portability, the devices become too costly to use. Bathing them in 
liquid requires dismantling and cleaning before reuse -- another costly 
process. Further, most of these prior art devices are rigidly fixed or 
mounted either internal or partially internal to the tank. Such mounting 
eliminates them from use rapidly between drums and prevents them .+-.rom 
being used as portable or "add-on" units. 
SUMMARY OF THE INVENTION 
This invention is a highly versatile add-on, float-operated, liquid 
shut-off valve that overcomes all of the problems associated with the 
prior art. It is totally portable and moveable from one vessel to another 
with little effort. No liquid passes through the valve thus allowing it to 
be used with different liquids without dismantling and/or cleaning. 
The invention comprises a valve body having a flange at one end for 
abutting against an opening in a tank and a collar positioned over the 
body, containing threads for matching engagement with threads formed on 
the inside of the periphery of the bung hole or other aperture through 
which it is inserted. Spaced-apart pneumatic power ingress and egress 
means are mounted in the flanged end of the body and are interconnected 
inside the body by a pair of separate passageways and separated by a shaft 
pivotally housed in a bore formed in the body, one end of which exits the 
body and interconnects through an extended arm to a float that rides on 
top of the liquid being pumped into the vessel. A pneumatic source is 
attached to the ingress means for passage of compressed gas or air through 
the ingress passageway to the shaft where its flow is stopped from further 
advance by the transverse mounted pivotal shaft. 
The float is set in registration with a cross-bore formed in the shaft such 
that compressed gas passes from the ingress passageway through the shaft 
cross-bore and out through the egress passageway and out of the valve body 
into a liquid pump for delivering a quantity of liquid into the tank. As 
the float rises on top of the level of liquid in the tank, it rotates the 
shaft until, at the uppermost and safest level of the liquid, the shaft 
has turned so that it shuts off further air flow to the pump thereby 
shutting it down and causing a cessation of liquid delivery into the tank. 
Thereafter, the collar may be easily rotated to disengage the threads for 
removal of the whole valve assembly from the bung hole and the valve 
assembly quickly moved to another location. Only the bottom of the float 
need be cleaned of the liquid because the valve body and all other 
components are suspended above and out of contact with the liquid. When 
the tank is drained of liquid or the valve is removed to an empty tank, 
the valve automatically re-sets itself; a feature not often found in the 
prior art. 
The invention is unique in that it is especially useful in the toxic waste 
industry because only gas, such as air, passes through the valve and such 
will not jam or otherwise damage the internal workings of the valve thus 
reducing the cost of cleaning the shutoff valve for later re-use. Further, 
the invention is unique in that the float is made in a diameter that will 
allow it to pass through the same opening in which the valve body is 
inserted. The valve body, connecting arm and float are made in a unique 
assembly to allow them to be inserted in a fully assembled form through 
the standard ASTM bung hole of a 55-gallon drum for immediate use. After 
the tank is full, the assembly is able to be withdrawn, the outside of the 
float, the connecting arm and any portion of the valve body that came in 
contact with the liquid being stored in the drum may be easily washed and 
thereafter the unit may be quickly moved to another tank and reinserted 
for future use with the same or with a different liquid. The valve and its 
components are made of nonreactive metal such as stainless steel and 
non-sparking material such as aluminum or brass and is otherwise a safe 
product. Even further, certain liquids may only be pumped under a blanket 
of inert gas, such as carbon dioxide, and this valve operates with a wide 
range of compressed gasses to provide another measure of safety to the 
operation. 
In another embodiment of this invention, the valve can be modified to 
provide a diversion of some of the pneumatic power from the passageway 
leading to the liquid pump to an audible whistle, such as an air horn, to 
warn the user that the tank is full and the liquid pump is shut off. This 
is associated with the feature of cutting off pneumatic power to the 
liquid transfer pump so that the tank is not overfilled while, at the same 
time, the user is warned that further storage will require the tank to be 
drained or use of another empty vessel. 
Accordingly, the main object of this invention is a floatoperated, add-on 
valve for use in the toxic liquid storage field that is easy to install in 
a variety of locations about the storage tank and is useful when 
positioned in the top or the side of the storage vessel to cut off the 
flow of liquid entering a vessel to prevent overflow and thus maintain a 
safe and non-toxic environment. It is characterized by having the body 
suspended above the liquid level in the vessel and having a float that 
drops down below the valve body to contact the liquid thus keeping the 
valve body free of the liquid. Other objects include a valve whose valve 
body, float and float arm can be inserted in complete assembly into the 
standard bung holes of various tanks without disassembly or without 
further modification of the tank; a valve that operates independent of the 
liquid being pumped; a valve that does not pass the liquid therethrough so 
as to be free of the effects thereof, and a valve that is usable without 
the need of observational personnel to monitor its operation. These and 
other objects will become more apparent when reading the Description of 
the Preferred Embodiment taken together with the Drawings appended 
hereto., The scope of protection sought by the inventor may be gleaned 
from a fair reading of the claims that conclude this specification.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
As shown in the drawings, where like elements are identified with like 
numerals throughout the eight figures, FIG. 1 shows the invention used in 
a typical toxic liquid storage system wherein the toxic liquid 1 is drawn 
from a sump 3 via a first transfer hose 5 to a pump 7 where it is pumped 
through a second transfer hose 9 into a standard 55-gallon drum 11 through 
an aperture 13 formed in the lid 15 thereof. Liquid 1 is not touched by 
human hands in this pumping system and the overall safety of the process 
is maintained. Pneumatic power, in this case air, is developed by a 
typical air compressor 17, powered by an electric line 19, that is 
delivered to pump 7 through the novel valve 21 of this invention by air 
transfer lines or hoses 23 and 25. As shown, valve 21 operates independent 
of liquid 1 and is neither contaminated thereby nor in need of cleaning 
after drum 11 becomes full. 
As shown in FIGS. 2 through 5 and FIGS. 7 and 8, valve 21 comprises a valve 
body 27, preferably cylindrical in shape and of a diameter small enough to 
allow it to be inserted (along with its float and arm that are described 
later) through a standard ASTM bung hole 29 in drum lid 15. Body 27 is 
also preferably made of metal, such as stainless steel or brass, both for 
sturdiness and for inertness to liquids being pump into drum 11, as well 
as to create a non-spark environment. 
Valve body 27 is terminated by spaced-apart first and second ends 31 and 33 
respectively. At end 31 is formed an outwardly extending flange 35 for 
supporting valve body 27 on an attachment means 28 positioned therebelow. 
Preferably attachment means 28 comprises a short non-ferrous collar 37 
that is provided with a series of outer threads 39, for engagement with a 
like series of threads 41 typically formed in bung hole periphery 43, and 
is held in sealed engagement with valve body 27 by 0-ring 45 retained in a 
seal groove 47. Valve body 27 may be easily inserted in bung hole 29 and 
collar 37 twisted to engage threads 39 and 41 to mount valve 21 rigidly 
therein. 
Means 49 for providing pneumatic ingress and egress to valve body 27 is 
formed in valve body first end 31 in spaced-apart relation for connection 
respectively to air compressor 17 and pump 7. As shown, means 49 includes 
a pair of threaded apertures 51i and 51o, formed in first end 31 wherein 
"i" indicates an inlet for compressed gas and "o" indicates an outlet for 
same. Female quickdisconnect type fitting 53o and male quick-disconnect 
type fitting 53i are threadably received in apertures 51i and 51o 
respectively for later receipt of similar respective male- and female-type 
fittings that are connected to first and second transfer hoses 23 and 25. 
A pair of first and second spaced-apart pneumatic passageways 55i and 55o 
are formed interior of valve body 27, preferably in parallel, spaced-apart 
arrangement as shown, for interconnecting ingress and egress means 49 and 
are interconnected by a third passageway 57 positioned transverse between 
the ends thereof and containing a clean out plug 59. A shaft 61 is 
pivotally received in a shaft bore 63, formed in valve body 27, for 
intercepting third pneumatic passageway 57 and is journaled in a pair of 
spaced-apart O-rings 65 that are in turn seated in grooves 67 formed in 
shaft 61. Other such sealing means are contemplated in lieu of O-rings 65 
and are within the scope of this invention. Shaft 61 is preferably set in 
axial alignment parallel to the plane of drum lid 15. 
Shaft 61 is terminated by a first shaft end 69 that extends outside valve 
body 27 and is adapted to be attached through connection means 71 to an 
arm 73 that is in turn attached to a float 75 adapted to float upon the 
surface of liquid 1. Connection means 71 may be chosen from a wide variety 
of means shown in FIG. 7 including a cross-bore 77 formed in shaft end 69 
through which arm 73 is inserted. Other means are shown in FIG. 7 
including an end-cap 79 in which the end 81 of arm 73 is mounted, said end 
cap 79 arranged for attachment with pins 83, received in pin holes 85 
formed in end-cap 79 and held therein by receipt of a threaded bolt with 
lock washer 87 in a threaded aperture 89 formed in shaft end 69. 
A still further means of attaching arm 73 to shaft end 69 is by the use of 
a clamp 91 in which arm end 81 is mounted, said clamp containing an 
aperture 93 for receipt of shaft end 69 and further containing a slot 95 
and a bolt 97 received transverse thereto for tightening clamp 91 about 
shaft end 69. These means allow float 75 and arm 73 to be adjusted with 
respect to shaft 61 to activate valve 21 to shut off air flow at different 
levels of liquid in drum 11. 
Float 75 Is made tubular in overall length having a diameter "D" slightly 
less than the diameter of bung hole 29. Further, arm 73 contains a bend 
100 that permits it to be assembled, along with valve body 27 and float 75 
into an elongated configuration, shown in FIG. 8, that is readily 
insertable through bung hole 29. 
It is preferred to limit the movement of arm 73 and float 75 to a 
predetermined path so that insertion of the fully assembled add-on valve 
into the dark interior of the tank will not be in such a manner as to have 
the float rise on the top of the liquid and contact the sidewall of the 
tank such that the valve will not shut off when the liquid has reached the 
predetermined level. To insure that float 75 is confined to the 
predetermined path and not move across the vertical center line C--C of 
valve body 27, means 98 is employed as shown in FIGS. 2 and 7. Means 98 
comprises a first abutment 99a formed on valve body 27 and extends outward 
therefrom to intercept arm 73 during movement thereof, i.e., as it is 
lowered to prevent arm 73 and float 75 from moving below the lowermost 
portion of the predetermined path that is shown in phantom in FIG. 8. 
Means 98 also includes a second abutment 99b formed in valve body 27 and 
extending outward therefrom to intercept arm 73 during movement thereof, 
i.e., as float 73 raises on the liquid being pumped into the tank, to 
prevent arm 73 and float 75 from moving beyond the uppermost portion of 
the aforesaid predetermined path. 
A fourth pneumatic passageway 101 is formed in shaft 61, intersecting third 
pneumatic passageway 57, preferably transverse of the long axis thereof, 
having openings or apertures 103i and 103o that register with intersected 
third pneumatic passageway 57 during the rotation of shaft 61 from the 
rising level of liquid in drum 11. When the level of liquid 1 reaches the 
uppermost level desired in drum 11, pneumatic passageway 101 passes out of 
registration with third intersecting pneumatic passageway 57 thereby 
interrupting the flow of compressed gas from compressor 17 to pump 7 and 
stopping the influx of any more liquid into drum 11. Connection means 71 
is strategically positioned between shaft 61 and float arm 73 to adjust 
the position of arm 73 with air passageway apertures 103i and 103o so that 
the uppermost level of liquid in the drum may be adjusted at will. 
While air passageway 101 is preferred to be merely formed or bored 
transverse to the long axis of shaft 61 it can be offset in different 
directions and, further, may comprise more than one passageway and still 
come within the spirit and scope of this invention. 
While the above-described invention works very well, there is no indication 
that the level of liquid 1 has risen in drum 11 to the desired level or 
that pumping has ceased except for a change in the noise level of air 
passing through transfer hoses 23 and 25. To remedy this situation, 
another embodiment of this invention is to utilize a fifth air passageway 
105, formed in valve body 27, extending from body top end 31 down to 
intersect bore 63 at a point spaced apart from third passageway 57. A 
separate, sixth pneumatic passageway, in the form of a groove 107, is 
formed in shaft 61 for interconnection with incoming air from first 
passageway 55i and third passageway 57 and is adapted to register with 
fifth passageway 105 when the air is shut off from outgoing passageway 
55o. 
A signal means 109, such as an audible whistle 111, is operably connected 
to fifth passageway 105 and remains dormant during operation of the 
invention while liquid 1 is below the uppermost desired level. When float 
75 is raised by the liquid to the uppermost desired level, fourth 
pneumatic passageway 101 rotates on shaft 65 out of registry with third 
pneumatic passageway 57 to shut down pump 7 simultaneous with rotation of 
groove 107 into registration with fifth pneumatic passageway 105 passing 
pneumatic power to whistle 111. Accordingly, as pump 7 is deprived of 
compressed gas and stops pumping liquid 1 into drum 11, whistle 111 is 
activated by the compressed gas and calls attention to the operator that 
drum 11 is now full and the pumping has ceased. Another waste drum 11 may 
then be quickly rolled into position, valve body 27, arm 73 and float 75 
removed from the full drum and installed on the new, empty drum 11. As can 
be appreciated, signal means 109 may take a wide variety of forms and yet 
remain within the spirit and scope of this invention. 
Since arm 73 and float 75 are shielded from view after being inserted in 
drum 11, it is preferred to have some indication of the orientation of 
valve body 27 vis-a-vis float 75. For this reason, visual indicia such as 
the picture of an arrow and the word, "float", shown at 113 is engraved or 
otherwise affixed to the upper surface of first valve body end 31 as shown 
in FIG. 3 so that valve body 27 may be easily and readily properly 
oriented in bung hole 29. Further visual indicia in the form of words, 
"in" and "out" are affixed to the upper surface of first valve body end 31 
adjacent respective apertures 51i and 51o to aid the operator in knowing 
which aperture to affix the respective pneumatic lines. 
Because collar 37 is preferably made of non-ferrous material, there is 
always the potential for the accumulation of a static charge on valve body 
27 during the passage of compressed air or other gas therethrough. As a 
precaution, means 115 is provided for connecting valve body 27 to an 
electrical ground. As shown in FIG. 3, means 115 may conveniently take the 
form of a bolt, machine screw or other device threadably received in first 
valve body end 31 for connection via an electrical cable or wire to an 
appropriate electrical ground.