FLOW CONTROL VALVE ASSEMBLY
BACKGROUND OF THE INVENTION 1. Field of the invention. This invention relates to a flow control valve assembly. The invention particularly relates to, but is not limited to, a flow control valve assembly for protecting containers against overfilling of fluids (or liquids); and to a flow control valve for the same. The term "container" will be used to include a tank, a drum, fluid (or fuel) cell, fluid bag (or fuel or other suitable storage device for liquids) 2. Prior art. they pump liquids, such as fuels, under pressure into vessels (eg, diesel, petroleum) A supply hose, connected to the outlet of a pressure pump, is usually provided with a flow nozzle that can The flow nozzles are usually provided with shut-off valves to stop the flow of liquid to the container when the container is full, however, experience has shown that operators have a habit. of manually over-working the shut-off valves, so that the shut-off valves can be "disconnected" before the containers are full, in some cases, eg When the fuel tanks are filled over large equipment, eg, excavators, and mining equipment, the operators manually overwork the shut-off valves to the extent that the fluid pressure causes the fuel tank to leak. they beat and, they still break. Clearly, the damage to the tanks and the loss of fuel are unacceptable. SUMMARY OF THE INVENTION It is an object of the present invention to provide a fluid control valve which can not be overworked manually. It is a preferred object of the present invention to provide such a control valve in the liquid coupling connected to the fluid nozzle. It is a further preferred objective to provide such a valve which is connected to a fluid level sensor in the container, wherein the sensor operates the valve to close the fluid flow when the fluid level in the container reaches the previously established level. It is a further preferred object of the present invention to provide such a flow control valve assembly which is suitable for the installation of new containers, or which may be retro-coupled to existing containers. It is still a further preferred object of the present invention to provide such a set which is inexpensive to manufacture and installation, and which is reliable and has low maintenance requirements. Other preferred objectives of the present invention will be apparent from the following description. In one aspect, the present invention resides in a flow control valve (for fluids) that includes: A valve body containing a first chamber connected to or adjacent an end to a fluid inlet, the fluid inlet that is it can connect to a source of fluid under pressure, and a second chamber connected to a fluid outlet, the fluid outlet that can be connected to a container (as defined above) that is filled with fluid; at least one passage of fluid or fluid port that injects the first and second chamber; a drainage passage in, or adjacent to, an end opposite the first chamber, which can be connected to a fluid level sensor in the container; and a piston, having at least one drainage hole therethrough, urged toward a first position by closing the passage of fluid (s) or fluid port (s) by means of a resilient member; arranged in such a way that: when the fluid level sensor senses that the fluid level in the container is below a pre-set level, a portion of the fluid from the fluid inlet is drained through the drain port in the piston and through the drain passage, to allow fluid pressure to move the piston to a second position, against the resilient member, allowing fluid to flow from the fluid inlet through the first chamber, fluid passages or ports of fluid, and then through the second chamber at the exit; but when the fluid level sensor senses that the fluid level has reached (or exceeded) a pre-set level, the fluid level sensor closes the fluid flow through the drain passage to equalize the fluid pressure on both sides of the piston in the first chamber, and the resilient member pushes the piston to the first position to close the fluid flow from the fluid inlet to the fluid outlet and in the same way the fluid flow from the fluid source to the container . Preferably, the valve body is assembled from two or three portions of the valve body, which are preferably connected by means of a threaded screw. Preferably, a main body portion incorporates a coupling member releasably coupled to a fluid nozzle, (the portion of the main body can be omitted, wherein the coupling member fits an end wall of a central body portion). Preferably, the potion of the central body forms the first chamber, in which the piston is mounted; and wherein the resilient member in the form of a compression coil spring (or similar resilient component) urges the piston into a first position that closes one or more passages of fluid through a cylindrical wall of the chamber. Preferably, a drainage passage is provided at the end (downstream) of the first chamber and is connectable, e.g. , by a drain pipe or hose, to the fluid level sensor, which may comprise a float valve (or other suitable fluid collection means) incorporating a valve which can control the flow of fluid through the passage of fluid drainage. Preferably, the end body portion, which defines the second chamber, at least partially surrounded by the central body portion to allow the fluid to flow through the fluid port or port to a connectable fluid outlet, e.g. , by a hose or pipe, to the container. In a second aspect, the present invention resides in a fluid flow control assembly that includes: a flow control valve as described above; and a fluid level sensor, mountable on or above the fluid container and operably connectable to the fluid drain passage. BR EVE DESCRIPTION OF THE DIAMETERS In order to be able to fully understand the invention, a preferred embodiment will be described with reference to the accompanying drawings, in which:
FIG. 1 illustrates the installation of the fluid control valve assembly on a tank; FIGS. 2 and 3 are respective sectional side views wherein the piston in the fluid flow control valve is shown in its first and second positions, respectively; FIG. 4 is a developed view of the components of the fluid flow valve assembly; and FIG. 5 is a sectional view, on an enlarged scale, of the central portion of the body of the flow control valve. DETAILED DESCRIPTION OF THE PREFERRED MODALITIES Referring to FIGS 1 to 4, the fluid flow assembly 10 is mounted on a fuel tank 100 which is filled to a pre-set fluid level 101. A respirator 102 on the upper wall 103 allows air to escape just as fuel is pumped into the tank via an inlet pipe. The fuel is supplied from a storage tank 110 under pressure from a pump 11 to a filling nozzle 112. The filling nozzle 112 has an internal shut-off valve and has the female portion 113 of a releasable fluid coupling (the male portion). which is provided by means of the fluid flow control assembly 10). The fluid level in the tank 100 is monitored by means of a fluid level sensor 20 mounted under the upper wall 103 of the tank 100 and a float 21 is operable to close a flow valve assembly 22 when the fluid level in the tank reaches (or exceeds) a pre-established level 101. The mounting base 23 of the fluid level sensor assembly 20 is mounted in sealed form to the upper wall 103 of the tank. A flow control valve 30 has a valve body from a central body portion 31 shown in enlarged detail in FIG. 5, is screwed into the screw at one end to receive a main body portion 32, provided with the male coupling member 33 of the releasable fluid coupling. (The male coupling member may be coupled to a hole by means of a threaded screw in an end wall of the central body portion 31). The central body portion 31 has a substantially flat hole 34 and is closed at its end under current by an end wall 35. At least one fluid passage 36 extends through the cylindrical wall 37 of the central portion, while a fluid drain passage 38 extends from the end wall 35 and through the indian cylindrical wall 37, to an outlet 39 adapted to receive a coupling 40 at one end of a fluid draining pipe 41, having a coupling 42 at the other end connected to the fluid level sensor 20. A piston 43, having a drainage passageway 44 therethrough, is slidably received in the flat hole 34 of the first chamber 45 within the central body portion 31. . A compression coil spring 46 is interposed between the end wall 35 and the piston 43, and can be operated to urge the piston 43 to a first position in the first chamber 45 where it closes the passage of fluid 36. A portion of the body end 47 has a cylindrical wall 48 engaged by threaded screws with the outside of the wall 37 of the central body portion to form a second chamber 51 connected to the first chamber 45 by means of the fluid passage 36. An end wall 49 has a peripheral flange with threaded screw 50 to allow coupling of the flow control valve 30 to the inlet pipe 104. A ring seal O 52 seals the portions of the valve body 31, 47; and a circular pin 53, in the first chamber 45, limits the movement of the piston within the first chamber 45. The fluid can flow from the first chamber 45 through the fluid passages 36 to the second chamber 51 to the inlet pipe. 104. The operation of the flow control valve assembly will be described shortly. The flow control valve assembly is installed as illustrated in FIGS. 1 to 4. When the filling nozzle 112 is connected to the male coupling 33, and the fluid is pumped under pressure by the pump 111, the fluid pressure on the upstream face of the piston 43 moves the piston, against a compression spring 46 towards the end wall 35 (ie, a second position) to open the fluid passages 36. The fluid flows from the first chamber 45, through the fluid passages 36, to the second chamber 52, and subsequently through the fluid inlet pipe 104 to the tank 103. A portion of the fluid passages through the drain hole 44 (in the piston 43) and flows through the drain passage 38, via drain pipe 41 to the tank 103, the valve member
22 in the fluid level sensor 20 which is kept open by means of the float of the valve 21. When the float of the valve 21 realizes that the level of the fluid has reached the pre-set level 101, it closes the member of the valve 22 which prevents fluid from flowing through the drain passage 38. Pressures on both sides of the piston 43 (in fuel chamber 45) are equalized, and the compression spring 46 pushes the piston in through to the first position where it closes the fluid passages 36, to prevent any further fluid flow through the fluid valve 30 (and the inlet pipe 104) to the tank. Even if the operator tries to manually overwork the automatic shut-off valve in the flow nozzle 1 12, in addition fluid flow to the tank 100 is prevented by the flow control valve 30. By means of selective adjustment of the operation of the float of the valve 21, the pre-set level 101 in the tank 100 can be easily established. It will be readily apparent to those skilled in the art that the fluid flow control valve assembly 10 can ensure that tank 100 (or another container coupled with the assembly) can not overfill. The assembly 10 can be easily installed in new tanks or containers, or retro-fitted to existing containers where the only additional hole required may be a hole in the upper wall 103 to enable the installation of the fluid level sensor 20, as well as the flow control valve 30 can be coupled (in line) between the existing (or adapted) inlet pipe 104 and the male fluid coupling 33 that can be connected to the female coupling 1 13 over the fluid nozzle
1 12. If any foreign material enters the flow control valve 30, the flow control valve can be easily disassembled to enable removal of the foreign body. In addition, springs 46 that have different compression characteristics can be easily replaced in valve 30 to control flow control characteristics. Various changes and modifications can be made to the embodiments described and illustrated without departing from the present invention.