FIELD OF THE INVENTION

[0001] This invention relates to non-refillable valve for a pressure container.

[0002] There is a need for a relatively simple and inexpensive valve which will allow evacuation and normal filling of the pressure container under normal pressure and temperature conditions, adequate filling of the pressure container during charging, selective discharge of the pressure container, and effective prevention of improper and unauthorized refilling of the container.

BACKGROUND OF THE INVENTION

[0003] Pressure tanks or other pressure containers are usually filled under carefully controlled conditions at a charging station and then distributed to various places for use. When empty, it is intended that the containers be disposed of for destruction in the case of single use containers. Unfortunately, the attractive economics of refilling containers at points of use or otherwise re-pressurizing them under less than carefully supervised conditions has resulted, in the less consequential cases, in the introduction of impurities or inferior refills and, in the more consequential cases, to injurious explosions. The re-use of pressure containers is highly objectionable for many reasons, which relate to safety.

[0004] U.S. Pat. No. 3,704,813 discloses a fluid dispensing valve assembly having a body one end of which is formed for securing to a container. The body forms a conduit having only one through passage for filling and discharging fluid. There is a shut-off valve operable for controlling the flow of fluid through the passage. The shut-off valve has an externally accessible control. There is a convertible means in the body comprising of an initially inactive check valve initially in condition to accommodate the flow of fluid through the passage in both the filling and discharge directions. The check valve is convertible after an initial filling operation into an active check valve in the passage in series with the shut-off valve. The initially inactive check valve includes a movable valve member, a valve seat, means for basing the valve member toward the valve seat, and detent means effective initially to prevent the co-operation of the valve member with the valve seat.

[0005] The detent means is inoperable, after an initial filling operation, to enable the valve member to engage on the seat. The check valve, when active, is operative to pass fluid only in the discharge direction. The check valve, after being rendered active to obstruct the flow of fluid selectively in the filling direction, is guarded against access from the exterior of the valve assembly when secured to a container for re-opening the passage to the flow of fluid in the filling direction. Thereby a container equipped with the valve assembly can be evacuated and then filled with fluid in the initial condition of the valve assembly but is substantially non-refillable after conversion of the convertible means.

[0006] U.S. Pat. No. 4,543,980 discloses a valve for a pressurized container having a blocking element therein which is adapted to occupy an initial location in which fluid can move in and out of the container past the blocking element. The valve and blocking element are further configured such that the blocking element can be irreversibly moved to a position in which the valve permits escape of fluid under pressure exerted from the inside of the container, but which automatically closes in response to exposure to an external pressure greater than the pressure inside the container. The blocking element is formed of at least one flexible radially extending arm whose lateral radius is reduced upon movement of the blocking element from the initial location to the final location. The at least one arm expands within the final location to prevent return of the blocking element to the initial location.

[0007] U.S. Pat. No. 4,573,611 discloses a non-refillable valve for a pressure container which includes a housing with a central bore, which has a lower portion that is narrower than its middle portion which in turn is narrower than its upper portion. A side port is present in the lower region of the middle portion and an outlet nozzle is attached to the side port.

[0008] The lower end of the housing is adapted to sealingly engage the pressure to provide communication there between. The valve stem is rotatably positioned in the upper portion of the central bore. A tube is mounted on the internal end of the valve stem, which extends to the middle portion of the central bore. A resilient valve sealing member has a body portion and an upper flange that extends upwardly and outwardly from the body. A longitudinal passageway is present part way through the body portion. A vertical post is positioned in the middle of the longitudinal passageway and slidingly engaging the tube on the bottom of the valve stem. The flange portion of the sealing member is compressingly positioned in the upper portion of the central bore when the valve is inactive or being filled. The valve sealing member is pushed into the middle portion by means of the valve stem when the valve is placed in the active position. The sealing member engages the seating interface when any refill of the container with pressurized fluid is attempted.

[0009] U.S. Pat. No. 4,813,575 discloses a non-refillable valve for a pressure container which includes a housing with a central bore which has a lower portion that is narrower than its middle portion which, in turn, is narrower than its upper portion. A side port is present in the lower region of the middle portion and an outlet nozzle is attached to the side port. The lower end of the housing is adapted to sealingly engage the pressure container to provide communication therebetween. The valve step is rotatably positioned in the upper portion of the central bore. The valve stem contains a vertical bore in its bottom portion. A resilient valve sealing member has a body portion and a top pin, which slidably fits into the bore in the valve stem. The sealing member has a top rim portion, which has a continuous outer surface and does not have any slots, indentations or the like. Also, the body portion does not have any arm or arms (particularly around its periphery). The top rim portion of the sealing member is comprisingly positioned in the upper portion of the central bore when the valve is inactive or being filled. The valve sealing member is pushed into the middle portion by means of the valve stem when the valve is placed in the active position. The non-compressed top rim of the sealing member is wider than the upper portion of the central bore, which prevents movement of the sealing member back into the upper portion of the central bore. The sealing member engages the seating interface when any refill of the container with pressurized fluid is attempted.

[0010] U.S. Pat. No. 5,295,502 discloses a non-refillable valve for a pressure container which includes a housing with a central passageway, which has a lower portion that is narrower than its middle portion which in turn is narrower than its upper portion. A side port is present in the lower region of the middle portion and an outlet nozzle is attached to the side port. The lower end of the housing is adapted to sealingly engage the pressure to provide communication there between. The valve stem is rotatably positioned in the upper portion of the central passageway. The internal end of the valve stem extends into the middle portion of the central passageway and has a longitudinal central bore present part way through the body portion. A resilient valve sealing member has a body portion and an upper flange that extends upwardly and outwardly from the body. A vertical post is positioned in the middle of the top surface of the upper flange and slidingly and rotatably engages the central bore on the bottom of the valve stem. A washer-shaped member fits over the vertical post in a slidable and rotatable manner. The washer-shaped member can be free floating on the valve sealing member or can be adhered to the bottom of the valve stem or top of the valve sealing member. The flange portion of the sealing member is compressingly positioned in the upper portion of the central bore when the valve is inactive or being filled. The valve sealing member is pushed into the middle portion by means of the valve stem when the valve is placed in the active position. The sealing member engages the seating interface when any refill of the container with pressurized fluid is attempted.

THE SUMMARY OF THE INVENTION

[0011] An object of the invention is to provide a non-refillable valve for compressed gas containers/cylinders.

[0012] Another object of the invention is to supply the pressure container with the valve in the closed position to the charging station with a positive pressure of an inert gas such as Nitrogen inside the container to prevent any rusting inside the container and thereby reducing the possibility of contamination or deterioration in the quality of the fluid that will be filled or discharged into or from the pressurized container.

[0013] A further object of the present invention resides in providing a valve system for containers of liquefied gas under pressure for allowing the container to be filled initially and in which the valve system can then be modified immediately after the first filling in a virtually permanent manner by the persons responsible for the first filling, for preventing subsequent filling operations.

[0014] A still further object of the invention resides in providing a valve system for dispensing liquefied fluid from a container in which there is provision for a first-time filling operation, readily modified after the first fill so that any attempts to refill the container would necessitate tampering and would leave tell-tale marks. This feature is aimed at providing a defense for the manufacturer who originally filled the container in case the container should later be refilled by another.

[0015] The foregoing and other objects of the invention and the various features of novelty and advantages will be more fully appreciated from the description below of the illustrative embodiments of the invention which are shown in the accompanying drawings. In each of these embodiments, there is a valve system for controlling the flow of fluid between an external port through which the fluid is supplied or discharged and an internal port that opens into the container. The valve system is secured permanently to the container. It has an external accessible operating part for opening the discharge passage, when required. The non-refillable arrangement for preventing the flow of fluid in the filling direction after the container has once been filled is housed in the port through which the fluid is discharged. The non-refilling arrangement is virtually inaccessible so that it remains effective to prevent a refilling operation. In each embodiment, the valve system includes provision for an initial filling operation that can be readily and, in a secured manner, modified for preventing refilling.

[0016] To achieve the said objectives, this invention provides a non-refillable valve for a pressure container comprising:

[0017] a housing having a central bore which has a lower and upper portion narrower than the middle portion, and having a side port communicating with the lower region of the middle portion of the central bore, the lower end of the said housing being adopted to sealingly engage on the pressure container in a manner which provides communication between the pressure container and the lower portion of the central bore;

[0018] an outlet nozzle having a horizontal bore lengthwise therethrough, the said outlet nozzle being positioned on the side of the housing and being in communication with the middle portion of the central bore through the side port in the housing;

[0019] a spindle with a stem and knob positioned in the upper portion of the central bore in a rotatable manner, which advances the stem of the spindle back and/or forth inside the central bore such that in the closed position of the valve, the bottom conical portion of the stem of the spindle will be positioned sealingly at the seating interface between the middle portion and the lower portion of the central bore, and in the open position of the valve, the bottom conical portion of the stem of the spindle will be in the lifted position thereby providing communication between the pressure container and outlet nozzle through the lower portion and middle portion of the central bore,

[0020] characterized in that a non-refillable device comprising of a spring loaded port sealing member having an end T-piece and a plug to hold the spring is provided at the outlet nozzle such that when the valve is in the active position of filling, the stem of the spindle is in the lifted position and the port sealing member is in the pulled position by means of the spring, thereby providing a communication between outlet nozzle and the container for filling and after completion of filling, the end T-piece is pulled and cut off whereby the port sealing member gets retracted, because of the spring, to seal the side port and thereby preventing the flow of fluid in the filling direction while permitting flow of fluid in the opposite direction for discharging.

[0021] The port sealing member comprising a cylindrical body having extensions on both sides, the diameter of the extension towards the side port is smaller than that of the cylindrical body and the extension towards outlet nozzle on the other side and the extension towards the outlet nozzle is further having an end T-piece.

[0022] The cylindrical body with extensions and the end T-piece form one single piece.

[0023] The pressure container is a pressurized gas container or a cylinder.

[0024] The container or cylinder contains inert gas at a positive pressure to prevent rusting before fitting.

[0025] The valve stem is mounted inside the upper portion of the central bore in a screwable manner.

[0026] The spindle stem has an externally located knob as an integral part for turning the spindle stem.

[0027] An O-ring is mounted in a groove in the spindle stem positioned in the upper portion of the central bore and sealingly engages with the upper portion or chamber of the central bore.

[0028] The port sealing member is made of a resilient plastic.

[0029] The spring used for maintaining the port sealing member in position is made of stainless steel.

[0030] The plug utilized for maintaining the non-refillable device in position is made of resilient plastic or is metallic and the outermost lip of the outlet nozzle is crimped.

[0031] As compared to the device of U.S. Pat. Nos. 4,543,980; 4,573,611; 4,813,575; 5,295,502; the present invention differs in that:

[0032] The non-refillable device is equipped inside the outlet nozzle and not in the central bore wherein the container or the gas cylinder can be supplied to the filler with the valve in the closed position with a positive pressure of inert gas to prevent any rusting inside the container or cylinder.

[0033] The possibility of unintentional closing of the valve by clock-wise rotation of the stem of the spindle is eliminated since the container or cylinder is supplied with the valve in the closed position.

[0034] The presence of Nitrogen or any inert atmosphere inside the pressurized container or cylinder will deter any rusting inside the container or cylinder thereby reducing the possibility of contamination of the fluid that will be filled or discharged into or from the pressurized container or cylinder.

[0035] The duration taken for filling or discharging the pressurized fluid into or from the container or cylinder is comparable with those of a container or cylinder not equipped with a non-refillable valve.

[0036] The non-refillable device of the instant invention is tamper-proof.

[0037] As compared to the device of U.S. Pat. No. 3,704,813 the present invention differs in that:

[0038] The threaded reducing nozzle at the outlet nozzle of the valve is eliminated for the reason that on removal of the threaded reducing nozzle at the outlet nozzle of the valve, refilling of the container or cylinder can be effected by extracting out the non-refillable device from inside the outlet nozzle of the valve.

[0039] The provision of a reducing nozzle at the outlet nozzle of the valve is economically disadvantageous.

[0040] The non-refillable device of the instant invention is tamper-proof.

BRIEF DESCRIPTIONS OF THE INVENTION

[0041] The present invention relates to non-refillable containers and in particular to a valve system for containers having provision for a first-time filling operation.

[0042] The invention valve is a non-refillable valve, which allows one filling and then selective discharging. The invention valve is designed to prevent, and does prevent, the refilling of pressure container. In this manner, the invention valve allows actual attainment of governmental requirement for a valve that prevents refilling of certain pressure containers.

[0043] The invention valve is effective, but relatively simple, and is inexpensive to construct. The invention valve is fail-proof in the matter of charging, storing and selective discharging. Subsequent filling of the pressure container is prevented by the invention valve.

[0044] The non-refillable valve of the invention can be used for fluid, that is gases and/or liquids. The fluid can contain solids that are discharged from the pressure container as entrained solids, etc., Many forms of liquefiable fluids are sold in disposable containers. Small metal tanks containing liquefied propane, liquefied butane and refrigerants, such as Freons are examples. When containers of such type are filled by manufacturer who has full control of the starting conditions of the containers and of the filling procedure and the specifications, a relatively safe product can be distributed to the end users. However, sometimes empty or partially empty containers are collected and these are refilled by poorly skilled and poorly equipped persons. The result is often a hazardous product. The non-refillable valve of the invention prevents such problems and associated danger.

[0045] By way of summary, the invention valve is installed on a container and shipped empty to the filler. Evacuation and filling of the container is achieved by means of a passageway through the outlet nozzle into the chamber in the valve housing and through the bottom passageway into the pressure container. The port sealing member is prevented from sealing the side port by means of a spring and the end T-piece attached to the port sealing member.

[0046] The valve is maintained in the closed position with a positive pressure of an inert gas inside during shipment to prevent any rusting inside the container and to prevent any contamination of the fluid that will be filled into the container. An O-ring seals the top turnable spindle stem during filling to prevent any loss of product to the atmosphere during the filling process. Initially, the valve is opened for the filling process. After filling the container with the desired quantity of the fluid, the valve is closed by turning the stem of the spindle towards downward condition. The end T-piece, on the port sealing member, is pulled out and severed whereby the port sealing member seals on the side port in a leak-proof manner. The container is ready for withdrawal of the fluid.

[0047] During withdrawal of the fluid from the pressure container, the pressure of the fluid is exerted on the port sealing member against the spring and the fluid is allowed to be discharged, as desired.

[0048] During any attempt to refill the container, the pressure from outside source will exert on the port sealing member in addition to the already exerted force by the spring whereby the side port will be sealingly engaged with the port sealing member. This will prevent any refilling of a partially or completely empty pressure container from an outside source.