AU675277B2 - Improvements in or relating to the electrical control of large diameter fluid valves, used in the control of trade waste or similar - Google Patents

Description

P/00/01 128/5/91 Regulation 3.2 Australia Pui tent:,sAct 1

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Invention Title IMPROVEMENTS IN OR RELATING TO THE ELECTRICAL CONTROL OF LARGE DIAMETER FLUID VALVES, USED IN THE CONTROL OF TRADE WASTE OR SIMILAR.

The invention is described in the following statement is 3 full description, including the best metiod of performing it known to me 1 A large diameter valve for electrical remote control of low pressure reticulation systems comprising a long large diameter pipe with two separate sealed chambers formed, one on either side with two or more slots in the circumference of this pipe irio each chamber, total area the slots in each side being the same area as the cross sectional area of the pipe. The slots on either side of the pipe are staggered with respect to one another by a distance equal to S the distance across a slot, and the space between each of the slots is approximately the same distance as the width of a slot. Within this tube a second shorter tube, which has a sliding fit within the main tube which has 2 (or 1 or more) slots corresponding to one of the sets of slots on the main tube but in this case, slots are completely circumferential, the tube being held together with narrow web supports across the slots. By moving the internal tube with respect to the main tube the slots can be made to coincide on one side, then if the intemal tube is moved one slot width then the slots will coincide on theother side of the main tube.

The one end of the main tube has a fluid proof end cap, through which a strong light shaft connects the sliding tube to an electro-magnet armature, through a fluid proof bearing. The sliding tube has a narrow web within it which is the means by which it is fixed to the shaft.

Movement of the electro- magnet armature thus can cause fluid flowing into the remote end of the long tube to be diverted via these sets of slots into the chamber on one side or the other, thus the fluid can be removed by suitable pipes, from these two side chambers. Me&ns can be provided to seal tie sliding pipe, to prevent fluid leaking across to the opposite slots through the sliding clearance between the two tubes, Since fluid is flowing within the moving pipe the web attaching it to the shaft which operates the valve from the electro-magnet, must be designed to give minimum obstruction turbulence to the fluid. A tension spring requires to be added to the electro-magnet armature to return it to the inoperative position when no power is supplied to the electro- magnet. Means may be provided to locate accurately the travel of the internal tube.

Page 1.

This invention relates to large diameter fluid valves which are not easily controlled by electromagnetic solenoids, since they require large movements to operate them which is not available from normal electromagnets. Operation of valves of large diameter say for 100mm diameter pipes is normally undertaken with pneumatic or hydraulic systems which of course require compressed air or oil thus adding to the cost and unreliability. There are some systems which have been described, such as Australian patents 11473/88 and 73471/87 which use an hydraulic closure using mains water pressure and not oil, but these will have limited use in climates in which freezing pipes can be experienced.This improvement relates to low pressure valves such as those used for diverting trade waste water from the storm water drains., such that pollutants did not get dischargedinto the natural waterway system. Legislation has 15.beenenacted to discourage trade users from polluting our rivers and waterways. The object of this invention is to describe a means whereby a normal electromagnetic solenoid which would normally operate over a distance of no more than 25mm's can operate a valve either for diversion purposes or as a open /closed valve for a 100mrn pipe. This invention also describes some ways that the valve may be controlled or used in water diversion schemes.

The present invention consists of a sealed box which is penetrated through two of its opposite sides by a long 100 mm diameter tube.

The box is divided into two chambers along the axis of the long tube by means of two oblong plates, one on the top and the other under Page 2.

the tube. The joints between the box and the tube and also between the two chambers are waterproof. The long tube is closed off at one end only with a lid, through the centre of which passes a stainless steel (or other metal) shaft by means of a waterproof bearing. The end of this shaft within the long tube is attached to a second short tube which slides within the long tube but fits closely. The rod is attached to the short tube by means of a web which gives minimum resistance to the passage of the fluid. The long tube within the box structure has two(one or more)diametric slots occupying from the top to bottom of the tube close to the box dividers mid way for support purposes narrow webs give strength to the structure where the material of the slots has been removed. The two slots within each of the chambers are displaced relative to one another by approximately one slot width. The short tube also has two (one or more) diametric 15.slotswhich go completely around the circumference of the tube, again displaced from one another by approximately a slot width.

Obviously to preserve the shape of this short tube narrow webs are required to hold the tube together.To give dimensions to this valve we would refer to an example say of valves suitable for a tube 100mm 20.diameter.The area of a 100 mm pipe is 7858 sq mm's thus the area S. of the two slots on each side of the long tube must be equal to this figure, or each slot must be 3929sqmm's. Each slot occupies half of the circumference of the long tube(neglecting the thickness of S" the chamber walls on the top and bottom and the width of the webs supporting strengthen the slots) which is equal to 157 mm thus the Page 3.

slot must be 3929 /157 which equals 25mm slot width. This is within the capabilities of an electro magnet. Obviously the short tube must also have slots this same width, since the slots in this tube must coincide with the slots in the long tube. For practical purposes it is necessary to seal around the slots to prevent fluid leakage and the method chosen in this example is to cut grooves into the short piston on each side of the slots which take neoprene rings so that the leakage from the slots is minimised. In order to make room for the "0" rings the solid islands between the slots should be lengthened by O.about 10 mm as will be shown in the drawings of the valve. Outlet tubes are fixed to each side of the box structure to give two alternate ways for fluid to be diverted. To complete the mechanical features of the valve a mesh filter should be mounted at the end of the long tube iwhich is the inlet point for the valve, a spring on the electro magnet 15.plunger to open the magnetic path once the current has been removed from the electro magnet. It may also be necessary for stops to be fitted at both extremes of the short tube travel so that the slots o I. on either side coincide with the slots in the outer tube. If fluid is introduced into the remote end of the long tube it will flow into the S 20.short tube through the two (one or more) radial slots to either one side chamber or the other depending upon the position of the short tube which in turn depends upon if the electromagnet has been actuated. By these means it can be seen that operation of the electro magnet will divert fluid from one side of the outlet box to the other from one outlet pipe to the h Other embobiments of this valve are possible since it is not essential that both chambers be on opposite sides they can be -one in front of the other as long as the short inner tube blocks one chamber and opens the other and vice versa. .vc\ve r- Page 4.

manner of this patent it may be used in various ways:- In a "wash down "situation where an hose is used to wash down a piece of plant or a vehicle which could produce pollutants, which get into the wash down water and require to be withheld from the "storm water" drains. The outlet tube on the side of the valve which is normally open is blocked off with a cap, and the normally closed side of the valve is connected to the sewer or holding tank for industrial waste. The valve is seated in the bottom of a drainage sump into which the waste water from the washing operation will flow.The'storm water' pipe is fitted near to the top of the sump. A flow switch is connected between the water mains supply and the "wash down", the ol° ~electrical signal from the flow switch can be used to switch on the power to the electro magnet. A timing device will require to be fitted which will keep the valve open for a time equal to that which is for the waste water from the wash operation to be drained into the drainage sump, when the flow switch turns off the electrical signal, which indicates that the tap has been turned off. When rain S falls on this "wash down" area the valve of course is closed and the sump will fill with the rain water and when full will flow down the 'storm 20.water' drain.

Another embodiment of the use of this invention is forthe said S* valve to be mounted in the bottom of a drainage sump with the normally open outlet pipe connected to the 'storm water' pipe and the normally closed outlet pipe connected to the sewer. The valve is by means of an electrical system operated by a pollution

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Page sensor. The sensor being chosen to measure the anticipated form of pollution which it is going to be present in this "wash down" situation.

For instance :-for washing down a vehicle a general hydrocarbon sensor would be used, for "washing down" plating or chemical vats then a specific heavy metal or cyanide, electro chemical sensor or perhaps a conductivity sensor, may require to be used. For the "wash down" of process plants requiring the use of acids or alkalis as for instance with processes using animal products. then a 'ph' sensor may be used. For "wash down" of brewery plant it may be that a or a C.O.D (Biological oxygen demand) monitor be used. In fertiliser plant a specific electrochemical probe for nitrogen would be used, for detecting blood or milk,turbidity detectors could be used .etc. In all of these examples as soon as a t' .shold quantity of pollutant is detected the valve operates and diverts the wash water from the 'storm water drains' to the sewer or for special holding or disposal or for treatment or neutralisation before being allowed to •:i be put down the sewer system. Any rain will go down the "storm water' drain because in the non operated position of the solenoid this is the way that is open.Should any pollution be washed into the sump 20. by rainfall, then the pollution detector wil detect it (provided it is the S same type of pollution that the detector can detect and shunt the polluted water into the sewer or holding tank. If the pollutant is explosive or can readily ignite, as with petrol, in any of these applications, then an intrinsically safe voltage should be used on the or the electromagnet can drive a master cylinder Page 6.

hydraulic unit( as in an automobile braking system remote from the valve and the slave unit which is actually close to the contaminated fluid drives the valve.ln this way the valve drive can be isolated, from any risk of explosion, and because of the hydraulic oil the unit will operate below the freezing point of water making its applications of far wider appeal than existing units which require water to actuate them A third use for this type of valve is for general low pressure control and reticulation of drainage pipes or the control of fluids in low pressure systems such as low vats tanks and sumps.

1 0.With the aide of the following drawings the invention will be described such that the operation of the valve and the applications of the valve can be understood, and the features of its construction may be noted.

Fig 1, shows a valve as described in this text. In it the box structure is shown as 1. and the long tube as there is a watertight seal on the 15.joints between 1.and Two waterproof bulkheads are formed by plates 3. and 4. which segregate the box structure 1. into two distinct compartments. On the one end of the long tube is a waterproof lid in the centre of which is a waterproof bearing 6. through which passes a stainless steel shaft 7. The other end of the long tube 2 will 20. normally have a leaf filter 41.to stop leaves and rubbish jamming the valve and preventing it from operating properly.There would be 42. a right angle bend on the input. On the stainless steel shaft projecting o from the long tube is attached an electromagnet 8. the body of which is fixed to the long tube by a frame 9. (in this case a second box) The solenoid of the electromagnet has attached a tension Page 7.

spring 10. whose function is to return the solenoid 11. to the non operated position with the solenoid right out of the magnetic circuit Attached to the end of the steel shaft 7. inside the long tube 2. within the area covered by the box 1.is a short tube 12. making close sliding contact within the long tube 2. The long tube within the box has two radial slots 13,14., and 15,16, in the tube each side within the boxes 1. The slots 13. and 14. are displaced relative to 15. and 16. by a distance equal to the width of the slots. In order to strengthen the structure about the slots there are narrow supporting webs 17. The 1 O.shaft 7. is fixed to the short tube 12. by means of a narrow web 18.

which does not cause any obstruction to the flow of any fluid passing through the long and short tubes 2. and 12. On the short tube are two slots 19. and 20. which are diametric and go completely around the circumference of the short tube.. To hold the second tube 12.

together are 8 thin webs 21 (4 on each slot). Fig 2. shows a sectional plan view of the long and short tubes 2. and 12.showing the relative positioning of the slots in the two tubes. To make a close fit between the twotubesthe material between the slots on both the long and short tubes is slightly wider than the slots 22. by about 10mm to 20. enable a narrow slot to be turned on either side of the slots on the tube to facilitate the fitting of 4 neoprene rings 23. which prevent fluid leaking out of the valve when the valve is closed. If the fluid in the 0 valve contains any flammable liquid then the voltage across the electromagnet can be reduced to an intrinsically safe voltage or the can be removed to a nearby safe location and an Page 8.

hydraulic Master/Slave cylinder can be used as in an automobile brake system, with the electromagnet 8. fixed to the Master cylinder 24. and the slave 25. attached to the valve stainless steel shaft 7. as shown in Fig With regard to the use of the valve in the various systems,Fig 4 shows a normal wash down situation in which the hose taps 26. are shown diagrammatically down line from the "wash off" hoses 27. Between the hose taps and the water mains supply is mounted a conventional flow switch 28. Any water flow will actuate the flow switch which passes a signal to an electronic OR gate 29.

and also to a delay unit 30. The output from this OR gate is used to drive a power driver 31 which switches a relay 32. which in turn switches the electromagnet 8.on It will be noted that the valve mounted at the bottom of a sump 33. and that the normally open side of the fluid valve is capped 34. and the valve operates as a open/ oe shut valve.The valve outlet is connected to the sewer or holding tank and the storm water drain 36. is connected to the top of sump 33.

From this diagram it can be seen that water flow through the hoses 27. due to the tap 26. being opened will give a signal to the delay 30 and to the relay driver 31 which operates the electromagnet S: 20. 8. via the relay 32.The valve 40. opens and the wash water goes into the sewer or holding tank via 35.With the close of the tap 26. the signal S. disappears but relay 32. is kept in for the length of the delaytime in the delay unit 30 to allow the remaining water to drain away. After this time the relay 32 opens and the diversion valve closes. Any rain that on the area will drain into the sump 33 and when it fills it then Page 9.

overflows into the storm water pipe 36. Thus preventing the "wash down" water from entering the storm water pipe.

In the configuration shown in Fig 5. the input to the valve is taken to the sump 33. and the two ports of the valve 40. are taken to the storm water pipe 36 and to the sewer or holding tank connection The normally open side of valve 40. being connected to the storm water pipe. rain thus goes directly into the storm water pipe 36. A partial wall 37. in the sump 33 causes the water to back up in front of it and a pollution probe 38 monitors the water at this point for signs of As soon as this occurs a signal is given to the electromagnet driver relay 32. which operates the valve 40. In this way the water entering the valve 40 is monitored and only polluted water is shunted into the sewer or holding tank 35. ie if during a wash down the water no longer shows signs of pollution it will be allowed to go oool 15.down the storm water pipe a sudden influx of polluted water will be detected at the wall 37. by the probe 38. and the valve 40 will divert the tainted water into the sewer pipe 35.. No examples are shown in the general low pressure reticulation field since the applications are two wide and general.

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Claims (2)

1. the mair- water supply and the on/off tap for the "washing down" station for vehicles or plant, such that turning on a hose tap causes the flow switch to actuate thus operating the electric or electronic logic which conti ols the electro magnet of the diversion valve, leaving on for sufficient time to allow the last waters to drain off and into the sump, under rainfall conditions rain will fill the sump and flow directly into the storm water outlet. A diversion valve as described above in Claim 1 fitted into the bottom of a sump the base of which contains a low partial wall such that fluid flowing into the sump from a from a poiluted source such as a"washing down" station" flows into the section behind the partial wall and builds up, there is a slow leak in the partial wall such that the reservoir so I 0.formed will leak out, within this reservoir a pollution detecting electrode is located which gives a signal to circuitry when pollution is detected in the reservoir, this signal drives either directly or indirectly the electro-magnet valve with valve outlets taken to the "storm water" or sewer pipe normally open side) and the treatment plant or a holding tank rcrmally closed side), no delay is required in this configuration since the fluid is measured prior getting to the valve, rain-water which falls on the ground washes polluting substance into the sump will be detected and diverted into holding tank, otherwise it will be flow into the normal stormwater or sewer pipe, the form of pollution detector will depend upon the type of pollution which it is anticipated will be encountered by the specific plant or equipment which is been used, these detectors could be for instance for hydrocarbons, S 20,for hydrogen ion activity( pH f r conductivity for use with chemical plant and plating and S etching vats, biological oxygen demand, or carbon oxygen demand or just dissolved oxygen for breweries and other food processes, specific heavy metal probes for mining plant and turbidity detectors for milk, blood animal products. 4].A diversion valve as described in Claim 1. controlled directly by an hydraulic remote operating the'drive shaft' of Claim 1.which in turn is actuated by a Master Cylinder type device as used in an Automobiles for Brake and Clutch operation, in which the shaft of the Master Cylinder is driven by an electro-magnet situated in a safe location away from explosive fumes, the advantage of this system over the normal hydraulic valves is that a supply of high pressure oil is normally required, whilst in this type of system the oil pressure for the slave unit to operate the valve is obtained from a reservoir of oil mounted over the Master Cylinder such that as soon as o the piston moves in the Master Cylinder, the piston cuts off the reservoir and compresses the oil inthe cylinder and in so doing compresses the oil in the remote Slave Cylinder which remotely operates the valve without the danger of electrical sparks which could cause an explosion.

35.5. A diversion valve as described above in claims 1 to 3 inclusive with a low voltage coil which is driven directly from solid state devices and as such is'intrinsically safe' and will give enough energy in any spark to ignite any explosive gases. 6.A diversion valve as herein described whether driven directly from solid state devices or relays or even hydraulic or mechanical devices as long as it uses the principles outlined in the above invention, that is a multitude of narrow apertures equivalent in area I Page 1 1. to the large inlet pipe which can be readily activated by an activator driving the small internal tube by moving only a small distance just slightly more than the distance across the small apertures to block or open the apertures which makes it ideal to be operated from a low energy device such as an electro magnet or other devices of a like nature it may be called a slide valve or a sleeve valve but in essence it will operate substantially as herein described. OOSS *0@ 0 e o .00. S 00 so 0: 00 0 S.. S.. 6 *r 0 0 0 M.C.KEARTON (Name of Applicant). Dated this 19th day of November (Date).. (Date) P/00/028 28/5/91