US3174503A

US3174503A - Automatic liquid flow arresting means

Info

Publication number: US3174503A
Authority: US
Inventors: Absolon Eric William
Original assignee: Avery Hardoll Ltd
Current assignee: Avery Hardoll Ltd
Priority date: 1962-02-28
Filing date: 1963-01-28
Publication date: 1965-03-23
Anticipated expiration: 1982-03-23
Also published as: GB968294A

Description

March 23, 1965 w, so o 3,174,503

- AUTOMATIC LIQUID FLOW ARRESTING MEANS Filed Jan. 28, 1963 2 Sheets-Sheet 1 INVENTOR ERIC w AasaLoN AT TORNEYS March 23, 1965 w. ABSOLON 3,174,503

AUTOMATIC LIQUID FLOW ARRESTING MEANS Filed Jan. 28, 1963 2 Sheets-Shee 2 ERIC. W- ABSOLON A T TORNE Y5 United States Patent 7,842/62 2 Claims. (m. 137-393) This invention relates to automatic liquid flow arresting means for arresting the flow of liquid into tanks or other receptacles when the liquid reaches a predetermined level therein.

Automatic liquid flow arresting means have been proposed in which some of the liquid being fed into the receptacle is directed through a nozzle to form a jet impinging on a Pitot head so as to create pressure in a conduit leading from the said Pitot head, which pressure is used to hold open a valve in a conduit through which the liquid is supplied to the receptacle, the action of the jet on the Pitot head being interrupted when the liquid reaches the predetermined level in the receptacle either by submergence of the jet .or by obstruction of an orifice through which the jet sucks air due to its injector effect.

Automatic liquid flow arresting means as defined in the last preceding paragraph are hereinafter called flow arresting means of the kind referred to, and the object of the present invention is to provide an improved form of such flow arresting means in which the shutting off of the liquid flowing into the receptacle is effected gradually.

According to the present invention, in an automatic liquid flow arresting means of the kind referred to, the pitot head is mounted substantially vertically below the nozzle, the Pitot head and nozzle being disposed at opposite ends of a bore .01 passage which is connected at its lower end to the interior of the receptacle and has an air inlet port adjacent its upper end also connected to the interior of the receptacle so that, with a rise of liquid in the receptacle between two predetermined levels the passage is progressively filled with liquid from its lower end and the air inlet port is submerged when the liquid reaches the upper of said predetermined levels.

The air inlet port may communicate with the interior of the receptacle through an upstanding pipe.

The Pitot head and structure defining the bore or passage are preferably housed in an open-topped enclosure mounted in the receptacle adjacent the top thereof and connected by a conduit to a point adjacent the bottom of said receptacle.

The invention is hereinafter described with reference to the accompanying drawings, in which:

FIGURE 1 is a general view of the flow arresting means according to the invention, the main parts being shown at least partly in section;

FIGURE 2 is a plan view of the controlling unit of the flow arresting means;

FIGURE 3 is a section on the line 33 of FIGURE 2; and

FIGURE 4 is a section on the line 4-4 of FIGURE 2.

Referring to the drawings, parts of the wall of a liquid tank, which may be the tank of a tank vehicle for delivering bulk supplies of liquids such as. motor fuels, are shown at 10. In the bottom of the tank is mounted a valve 11 through which the tank is filled and emptied, the valve being controlled automatically for filling and manually for releasing liquid from the tank.

Automatic control of the valve 11 is provided by a control unit 12 mounted on the wall of the tank near the top of the latter.

The valve 11 comprises a casing 13 fixed to an elbow 14 secured by bolts (not shown) passing through a flange 15 to the bottom wall of the tank around an opening there in, and a valve closure member 16 co-operating with a seat 17 in the end of the passage through the elbow 14. A piston 18 fixed to the valve closure member 16 is slidable in the casing 13 above a partition 19 dividing the said casing 13 into upper and lower chambers. The lower of these chambers, indicated by the reference 20, communicates through ports 21 with the interior of the tank.

The piston 18, which is of slightly larger diameter than the valve closure member 16, divides the chamber in the casing 13 above the partition 19 into two spaces 22 and 23. The space 22 .above the piston is in communication through a one way auxiliary valve 24 controlling a passage 25 in the valve closure member 16, with the interior of the elbow 14, so that a liquid pressure corresponding to that acting on the upstreamside of the valve closure member acts on the piston in a valve-closing direction. A spring 26 in the chamber 22 also acts on the piston in the same direction. The space 23 below the piston 18 is subject to the pressure created in the Pitot head which, as will be hereinafter described, is included in the control unit 12. The thrust on the valve closure member 16 due to the incoming liquid combined with the thrust on the piston 18 due to the pressure created in the Pitot head, is sufficient to hold the valve closure member off its seat, but when the pressure at the Pitot head is destroyed, the pressure acting on the upper side of the piston 18, and the spring 26 together produce a thrust suflicient to seat the valve closure member against the thrust due to the inflowing liquid.

The control unit 12 as shown in FIGURES 2, 3 and 4 comprises an open-topped bowl 27 mounted high up in the tank, being clamped by bolts 28 to a bracket 29 fixed to the inner side of the container wall 10 and formed with vertical slots 31 to receive the bolts 28 so that the position.

of the bowl 27 can be adjusted in a vertical direction. A vertical rib 32 projecting intothe bowl 27 includes a substantially cylindrical edge portion 33 formed with a passage 34 therethrough, the rib 32 and its edge portion 33 terminating short of the bottom of the bowl. A jet nozzle 35 is mounted on a shoulder 36 near the top end of {the passage 34 and is held against the said shoulder by a hpring 37 taking its abutment on a plug 38 closing the upper end of the passage. In the bottom of the bowl 2'7, 'coaxially with the passage 34, is mounted a Pitot head 39. Close to the tip of the jet nozzle 35 there opens into the passage 34 a lateral passage 41 (FIGURE 4) which is connected through an external lug 42 on the bowl to an upstanding tube 43. The tube 43 is preferably enclosed in a guard tube 44 secured by a set screw 45 to the lug 42, the guard tube 44 being notched at its lower end, at 46, to allow the free entry of liquid to the lower end thereof.

A conduit 47 (FIGURE 1) leads from the space 22 above the piston 18 to a lateral passage 48 for supplying liquid to the jet nozzle 35, and a conduit 49 leads from the Pitot head 39 to an inlet opening into the space 23 below the piston 18. A conduit 51 leads from the bottom of the bowl 27 to a point close to the bottom of the tank.

Liquid flows from the space in the chamber 22 above the piston 18 to the conduit 47 through an annular space 52 in a cylindrical body 53 depending into the said space. Liquid enters the said annular space 52 through a flow restricting device comprising a plunger 54 slidable against spring loading in a cylinder 55 defining the inner wall of the annular space 52 and in its normal position, as shown in FIGURE 1, restricting flow of liquid from a passage 56 leading from the chamber 22 to a passage 57 leading into the annular space 52.

The plunger 54 is capable of being displaced to permit free communication between the passages 56 and 57 by a rod 58 moved relatively to the valve closure member 16 Patented Mar. 23, 19

by initial movement of a valve-opening lever 59 the continued movement of which unseats the said valve closure member. The lever 59 enables the valve to be opened for the removal of liquid from the receptacle, the lifting of the plunger 54 allowing liquid to escape freely from the space above the piston 18 so that such liquid does not resist the opening of the valve.

The flow arresting means according to the invention operate in the following manner. When liquid is flowing into the receptacle through the valve 11 some of it passes through the passage 25 and conduit 47 to the jet nozzle 35, forming a jet of liquid which impinges on the Pitot head 39 and creates a pressure in the conduit 49 which, acting in the space 23, below the piston 18, helps to hold the valve open.

The nozzle 35 is so designed that, so long as air can enter the passage 34 freely through the passage 41, it produces a substantially cylindrical jet of liquid which impinges on the Pitot head 39 and thus causes pressure to be created in the space 23 below the piston 18 of the valve 11. Obstruction of the flow of air through the passage 41 causes the jet to spread out so that it no longer im- ,pinges on the Pitot head 39 and the pressure in the said space 23 is lost.

As the level of liquid in the receptacle rises it reaches a point at which it covers the Pitot head 39 and then rises progressively in the passage 34, thus to some extent obstructing the jet impinging on the Pitot head and so reducing the pressure in the space 23 below the piston 18 of the valve 11 and the thrust due to that pressure acting to hold the valve open. The valve closure member 16 therefore tends to move toward its seat and increase the restriction of flow of liquid past it so as to maintain a total opening thrust which prevents the valve from closing fully, the closing of the valve progressing as the depth of liquid between the jet nozzle 35 and the Pitot head 39 increases. Ultimately, the liquid in the receptacle reaches a level such that it submerges the upper end of the tube 43. The jet of liquid from the nozzle 35 can then no longer draw air through the tube 43, so that the jet spreads out and does not imping on the Pitot head 39. The pressure in the space below the piston 18 of the valve 11 is therefore completely lost, and the valve closes completely.

I claim:

1. In a liquid dispensing apparatus including a tank to be filled, a filling conduit connected to the tank through a valve enclosure having a valve element manually movable against spring pressure to open said filling conduit, a pair of chambers in the valve enclosure separated by a piston fixed to said valve element, the first of said chambers communicating with the interior of said tank, and means for communicating the second chamber with the first to admit liquid to the second chamber when the valve element is manually opened so as to neutralize the pressure on said element and piston of liquid flowing through the filling conduit, the improvements comprising an open top bowl supported in the tank near the level to which it is to be filled, a conduit through the bottom of the bowl connecting the bowl interior to a level near the bottom of the tank, a Pitot head mounted in the bottom of said bowl and connected by a conduit to said first chamber of the valve enclosure, a member in said bowl having a vertical bore axially aligned with said Pitot head, a jet nozzle disposed axially near the upper end of said bore, a conduit communicating said nozzle with the second chamber of said valve enclosure, and an air inlet port in said member communicating with said bore between the nozzle and the Pitot head, whereby with a rise of liquid in said bowl between two predetermined levels said bowl is progressively filled with liquid from its lower end progressively reducing pressure in said first chamber to gradually close said valve until the air inlet port is submerged when the liquid reaches the upper of said predetermined levels to automatically complete the closure of said valve.

2. Improvements in apparatus according to claim 1, wherein said air inlet port communicates with the interior of the tank through an upstanding pipe.

References Cited by the Examiner UNITED STATES PATENTS 2,796,090 6/57 Carriol 141-198 WILLIAM F. ODEA, Primary Examiner. LAVERNE D. GEIGER, Examiner.

Claims

1. IN A LIQUID DISPENSING APPARATUS INCLUDING A TANK TO BE FILLED, A FILLING CONDUIT CONNECTED TO THE TANK THROUGH A VALVED ENCLOSURE HAVING A VALVE ELEMENT MANUALLY MOVABLE AGAINST SPRING PRESSURE TO OPEN SAID FILLING CONDUIT, A PAIR OF CHAMBERS IN THE VALVE ENCLOSURE SEPARATE BY A PISTON FIXED TO SAID VALVE ENCLOSURE SEPARATED BY A BERS COMMUNICATING WITH THE INTERIOR OF SAID TANK, AND MEANS FOR COMMUNICATING THE SECOND CHAMBER WITH THE FIRST TO ADMIT LIQUID TO THE SECOND CHAMBER WHEN THE VALVE ELEMENT IS MANUALLY OPENED SO AS TO NEUTRALIZE THE PRESSURE ON SAID ELEMENT AND PISTON OF LIQUID FLOWING THROUGH THE FILLING CONDUIT, THE IMPROVEMENTS COMPRISING AN OPEN TOP BOWL SUPPORTED IN THE TANK NEAR THE LEVEL TO WHICH IT IS TO BE FILLED, A CONDUIT THROUGH THE BOTTOM OF THE BOWL CONNECTING THE BOWL INTERIOR TO A LEVEL NEAR THE BOTTOM OF SAID OF THE TANK, A PITOT HEAD MOUNTED IN THE BOTTOM OF SAID BOWL AND CONNECTED BY A CONDUIT TO SAID FIRST CHAMBER OF THE VALVE ENCLOSURE, A MEMBER IN SAID BOWL HAVING A VERTICAL BORE AXIALLY ALIGNED WITH SAID PITOT HEAD, A JET NOZZLE DISPOSED AXIALLY NEAR THE UPPER END OF SAID BORE, CONDUIT COMMUNICATING SAID NOZZLE WITH THE SECOND CHAMBER OF SAID VALVE ENCLOSURE, AND AN AIR INLET PORT IN SAID MEMBER COMMUNICATING WITH SAID BORE BETWEEN THE NOZZLE AND THE PITOT HEAD, WHEREBY WITH A RISE OF LIQUID IN SAID BOWL BETWEEN TWO PREDTERMINED LEVELS AND BOWL IS PROGRESSIVELY FILLED WITH LIQUID FROM ITS LOWER END PROGRESSIVELY REDUCING PRESSURE IN SAID FIRST CHAMBERS TO GRADUALLY CLOSE SAID VALVE UNIT THE AIR INLET PORT IS SUBMERGED WHEN THE LIQUID REACHES THE UPPER OF SAID PREDETERMINED LEVELS TO AUTOMATICALLY COMPLETE THE CLOSURE O SAID VALVE.