US2726674A

US2726674A - Filling attachment for fuel tanks for airplanes

Info

Publication number: US2726674A
Application number: US249336A
Authority: US
Inventors: Robert H Davies
Original assignee: Parker Appliance Co
Current assignee: Parker Appliance Co
Priority date: 1951-10-02
Filing date: 1951-10-02
Publication date: 1955-12-13
Anticipated expiration: 1972-12-13

Description

Dec. 13, 1955 D s 2,726,674

FILLING ATTACHMENT FOR FUEL TANKS FOR AIRPLANES Filed Oct. 2, 1951 2 Sheets-Sheet 1 IN V EN TOR.

M, Frrfil k Dec. 13, 1955 D V s 2,726,674

FILLING ATTACHMENT FOR FUEL TANKS FOR AIRPLANES Filed Oct. 2, 1951 2 Sheets-Sheet 2 I1EEE INVENTOR. fio Zerififfiayzks,

BY ww, IB'fEI ELa/L Vim difys,

United States Patent'G FILLING ATTACHNIEIJT FOR FUEL TANKS FQR AHKPLANES Robert H. Davies, Aurora, Ohio, assignor to The Parker Appliance Company, Cleveland, Ghio, a corporation of Ohio Application October 2, i951,v Serial No. 249,336

3 Claims. (Cl. 137-339) The invention relates to new and useful improvements in a filling attachment for tanks and in particular a fuel tankfor airplanes.

An object of the invention is to provide a filler valve for tanks which normally automatically controls the level to which the tank may be filled but which, in the event of malfunctioning will fail safe to either prevent initial filling of the tank if the valve becomes defective prior to the attempt to fill, or which will close to prevent further filling it" the defect occurs during the filling operation.

A further object is to provide a fail safe" filler valve of the above type wherein the valve opens against the pressure of the fuel supply and wherein means is provided for utilizing the fuel pressure for opening the valve.

A. further object is to provide a fail. safe filling attachment of the above type with means for releasing the pressure which opens the valve when the tank is filled to a predetermined level so that the valve may be closed by the pressure of the incoming fuel stream.

A. further object of the invention is to provide a filling attachment wherein the valve is connected to a movable wall of a chamber and fuel from the fuel supply is directed into said chamber for creating a pressure on said movable member for opening the valve.

A still further object of the invention is to provide a filling attachment of the above type wherein a diaphragm serves as the movable wall of the chamber so that a fracture of the diaphragm will prevent the accumulation of pressure in the chamber sufficient to open the valve.

A further object of the invention is to providev a filling attachment of the above type wherein a float. controlled pilot valve releases the pressure on said chamber when the tank is filled to a predetermined extent so that the main valve may be closed by the pressure of the fuel thereag ainst aided by its closing spring.

A still further object of the invention is toprovide a filling. attachment of the above type wherein the pilot valve is moved to a closed position. by a fluid retracted spring actuated device when the fuel supply is released from the attachment and wherein said pilot valve is moved to open position by a spring when fuel is again supplied to the attachment and operates on said device for retracting the same.

These and other objects will in part be'obvious and will in part be hereinafter more fully disclosed.

in the drawings which show one embodiment of the invention:

Figure l is a vertical sectional view through the filhng. attachment with the main valve in open position for supplying. fuel to the tank;

Figure 2 is a vertical sectional view through a part of the upper portion of the attachment with the tank filled to a predetermined degree, the float raisedv and the pilot valve shifted to closed position and the main valveclosed; and

Figure 3 is a view similar to Figure 2 but showing the pilot valve shifted to a closed position by aspring actuated sealing the connection. The extreme lower portion 6 of' the housing projects below the flange so' that a filling nozzle may be attached thereto.

The valve housing is in four sections. The lower section 7 carries the flange 2 and extends upwardly for some distance into the tank. At the upper end of this section 7 is a section 8 secured to said section 7 by bolts 9. Be-

tween the two sections is a gasket 10. The third section indicated at 11 is mounted on the section 8 and secured thereto by bolts 12. Between these two sections is a gasket 13.. Secured to the upper end of the third section 11 is a fourth section 14.

The section 11 has an opening 15 leading to the tank. Surrounding this opening is a valve seat 16. A valve 17 is made in two parts and a gasket 18 is clamped between the two parts and contacts the seat 16. These two parts are held together by means of bolts, one of which is indicated at 19. The upper part of the section 11 has a web 20 extending all the way across the upper end of said section. This web has. a depending cylindrical portion 21 and a horizontal portion 22 which. carries an upstanding hub 23. This hubhas a bore. which receives and guides a stem 24 which is rigidly secured to the valve 17 at its lower end and also secured to a diaphragm 25 at its upper end. There is a plate 26 below the diaphragm and a plate 27 above the diaphragm and the diaphragm is clamped between these two plates by a nut 28 pressing the plate 26 against the. end of the valve stem 24. There is a spring 29' which surrounds the hub 23 and at its lower end the spring bears against the portion 22 while at its upper end it bears against the plate 26. This spring normally moves the valve 17 upward andinto contact with its seat. In this figure the valve is shown. as open while in Figures 2 and 3 the valve is shown as moved to a closed position and held in said closed position by means of the spring 29.

The upper or fourth section 14: of the housing forms a cap or head for closing the housing and the diaphragm 25 extends outwardly between. the upper and third section and is held securely clamped between the two by means of bolts 30. The web 20 has an opening 31 leading to the tank. The extreme upper end portion 14 of the housing has an extension 32 which is bored to receive a pilot valve casing 33. This casing is held. in a fixed position in the extension 32 by a wedge fit. The casing has a central bore 34 in which is mounted a valve stem 35 having three spools. or

lands

3d, 37 and 38. The casing has radial passages leading to an annular recess 39. It also has radial passages. leading to an annular recess 40 and radial passages leading to an annular recess 41. There are annular recesses in the inner' face ofthe: casing which correspond to the annular recesses 39, 4.0 and 41. The lands on. the valve stem fit the. bore between and outsideof these annular grooves, so that. the lands contact with the bore" and prevent fluid communication past the lands. when contacting therewith.

There is a passage 42 which leads from the annular recess $0 to a. chamber 43 between the diaphragm 25 and the upper end of the housing, which chamber is; closed when this passage 42- is closed. There is. a bypass conduit 4 3 which connects with the interior of thehousing below the valve and this conduit is also connected to the recess 39' inthe valve casing. The left hand end' of the housing is closed bya plate 44-. The valve stem extends through an opening in this plate. Mounted'onthe valve stern for free sliding movement thereon is a washer 45. A collar 46 fixed to the stem by engagement with an annular groove therein is adapted to engage the outer face of thewasher 45. Mounted for free movement on the stem 35 is a sleeve 47 having a flange. Between the flange on this sleeve and the washer 45 is a spring 48. The sleeve is of less diameter than the land 36.

Mounted on the'housing extension 32 is a bracket arm 49. A float '50 of cork or like material is carried by an arm 51 which is pivoted at 52 to said bracket. This arm extends beyond the pivot and may be provided with a weight 53 to balance the float. A depending plate 54 carried by said arm 51 has an aperture'55 therethrough and the stem of the valve projects through this aperture and has a loose connection with this plate 54. This plate at the point of connection with the stem, of course, swings in an are about the pivot 52 but the loose connection with the stem permits the same to be moved in a straight line; When the parts are positioned as in Figure 1, then the pilot valve may be said to be in centered or open position. The

spring 48 is fully expanded and holds, the washer against the plate 44 and the sleeve 47 against the end of the'valve casing 33. When the parts are in this position then the annular recess 39 is connected to the annular recess 40 and through the passage 42 it is connected to the chamber 43.

.When the fuel supplying nozzle is connected to the housing it is under pressure and the fuel under pressure will pass through the conduit 43 and the passage 42 into the chamber 43. The area of the diaphragm 25 is larger than the area of the valve 17 and therefore there will be a differential pressure on the diaphragm 25 which is slightly greater than the pressure of the fuel against the valve 17 and this will move the valve to an open position as shown in Figure l, permitting fuel to pass around the valve and into the tank. It is noted that the valve is on the intake'side of the valve seat and has been opened Figure 1. There is a passage 65 connecting the conduit 43 with the bore 58. When the conduit is under fuel pressure the fuel will enter this passage 65 and bear against the inner face of the valve shifting device and force it to the position shown in Figure 1. This device may be said to be retracted by fluid pressure and actuated, that'is, moved inward to shift the valve, by spring pressure. The tension of the spring 64 is much greater than the tension on the centering spring 48, and overcomes the latter when the device 62 is not held in its retracted position by fluid pressure within the chamber 58. V

In order to protect the pilot valve and the float a relatively thin metal cover 66 completely houses the pilot valve and the float. This cover is secured to the housing section 14 by suitable screws 66 There are openings 70 through the side wall of the cover so that fluid in the tank when it rises to the level of the flo'at will enter the cover and engage the float. In other words, the fuel level in against the fuel pressure on the supply. The spring 29 is V The level at this time is at the predetermined level desired 7 in the tank. As the float rises to the position shown in Figure 2 it will move the pilot stem to the right as viewed in this Figure 2. This will shift the land 37 so as to close The filling of the tank will continue until the the opening between the conduit 43 and'the passage 42 leading to the chamber 43. The shifting of this land so as to close the passage between the fuel supply and the chamber 43 also opens the passage 42 to the recess 41 and the recess 41 is connected to the passage 56 which leads to the tank so that the pressure on the upper side of the diaphragm is released and the pressure of the fuel against the valve together with the tension of the valve spring 29 will move the valve to closed position-as shown in Figure 2.

The upper section 14 has a second extension 57 similar to the extension 32. It has a similar bore 58 and at its inner end it is closed by a member 59 except for an opening centrally thereof which is in alignment with the bore 34 in the valve casing 33. The outer end of this'e xtension 57 is closed by a plate 60 which is held in place in the bore by a split ring 61. Within the bore 58 is a valve shifting device62. This valve shifting device has a pro jecting stem 63 which is in alignment with the stem 35 of the valve. The valve'shifting device 62 closely fits the bore 58. There is a spring 64 located in a recess in the valve shifting device. This spring bears against the inner face of the recess and also against the plate 60 and normally tendstoshift the device tothe left as viewed in nozzle has not yet been opened to permit fuel under 7 pressure to enter the pipe 7, the parts of the filling attachment will be in the position as shown in Figure 3.

'In this position the main valve 17 is closed and the pilot valve 35 is held in its leftward position by the valve shifting device 62 due to the action of the spring 64. The float 50 will be held in the downward position as shown because of its connection to the pilot valve.

With the pilot valve in the leftward position, the chamber 43 is open to the interior of the tankthrough the passage 42, the interior of the valve sleeve 33, and the passage 56. As soon as the nozzle is attached and opened to permit fuel under pressure to enter the pipe 7 fuel will pass through the conduit 43 and through the passage 65. Under pressure the .fuel will enter between the inner end of the valve shifting device 62 and the wall 59 and cause the valve actuating device 62 to move rightwardly against the action of the spring 64. This removes the valve shifting device so that it has no control over the pilot valve. The pilot valve will then become centered in the position shown in Figure 1 through the action of the centering spring 48. Movement of the pilot valve to its center position also causes the float 50 to be moved to its mid position.

As. soon as the pilot valve is moved to its center position, the fuel under pressure in the conduit 43 will have access to the chamber 43 above the diaphragm 25 through they interior of the valve sleeve 33 and the passage 42. Up to this time the fluid under pressure'within the pipe '7 has acted upon the lower side of the main valve 17 and ,has aided the spring 29 in holding the main valve in its'closed position. However, as soon as fluid under pressure has gained access to the chamber 43 it will act upon the upper surface of the diaphragm 25 and since the area of this surface is greater than the area of the lower face of the main valve 17, the main valve 17 will be moved to the open position and fluid from the pipe 7 will gain access to the interior of the tank past the valve seat 16 and the opening 15. The parts will then occupy the position as shown in Figure 1 and fluid will flow into the tank.

When the tank becomesfull the float 50 will be raised and cause the pilot valve tobe shifted to its rightward position as illustrated in Figure 2. This'causes the fluid under pressure to be cut off from the chamber 43 and simultaneously causes the chamber 43 to be vented through the pilot valve to the interior of the tank by means, of the, passage 56. When the pressure is cut 01f from the chamber 43 in this mannerv the spring 29 and the velocity pressure of the fluid impinging upon the lower surface of the main valve 17 causes the. latter to move upwardly againstthe seat 16 and thus stop further filling of the tank. If the fuel supply is then cut off, or the filling nozzle disconnected, the pressure of the fluid within the conduit 43 and chamber 58 will drop and the spring 64. will again cause the device 62 to shift the pivot valve to its leftward position, which inv turn will cause the float to move to its. lowermost position. The entire device will thenagain be in the position as shown. in Figure 3.v

From. this description it is seen that in the normal operation of the unit the pilotvalve controls the operation of the main valve so that the latter will open when fuel under pressure is. introduced into the pipe 7 and will close when the tank has been filled to a predetermined level. If for any reason the unit cannot function in its normal manner, the parts are so arranged that if the unit becomes defective prior to an attempt to fill the tank, the main valve Will not open when the attempt is made and thus it is indicated to the operator that the unit has become defective. On the other hand, if certain defects should occur during the actual filling operation, the main valve will automatically be caused to close so as to prevent overfilling or bursting of the tank. The following description will illustrate these fail safe features.

As indicated in the description of the normaloperation, as long as the filling nozzle is detached or not turned on, there is no pressure on the fuel which may have remained in the pipe 7 from prior filling operations. Consequently, there will be no fluid pressure within the chamber 58 and thus the spring 64 and the valve shifting device 62 will hold the pilot valve in its leftward position and the float in its downward position as shown in Figure 3. Suppose that before another attempt is made to fill the tank, the pivot valve has become stuck in this position because of corrosion, foreign matter, or other reasons, or suppose that the float has become logged or for some other reason has become stuck in its downward position. In any of these events, when it is again attempted to fill the tank and fuel under pressure is introduced into the pipe 7, the valve shifting device 62 will move to its retracted position as shown in Figure 2. This will release the pilot valve but the spring 48 will not be able to shift it from the leftward position shown in Figure 3 because of the sticking, logging of the float, or other defect that is interfering with the free movement of the pilot valve. Since the pilot valve has not assumed its center position, the fluid under pressure within the pipe 7 will be prevented from entering the diaphragm chamber 43 and thus the main valve will remain in its closed position. The consequent failure of the tank to start filling is an indication to the operator that the filling unit has become defective and should be serviced.

If the diaphragm 25 has become ruptured and an attempt is later made to fill the tank, fluid under pressure within the pipe 7 will retract the valve shifting device 62 and permit the pilot valve to open in its normal manner. However, the fluid entering the chamber 43 will pass through the ruptured diaphragm 25 and the pressure of the fluid will then become balanced on both sides of the diaphragm and there will be no differential pres- 7 sure for opening the main valve 17. Thus the operator will again be warned through the failure of the tank to start filling that the unit has become defective.

In another example, suppose the float has broken off prior to an attempt to fill the tank. In such case the pilot valve will remain in its leftward position as shown in Figure 3 until fluid under pressure is introduced into the pipe 7. The shifting device 62 will then retract to release the pilot valve but the latter, instead of becoming centered, will be immediately carried to its rightward position by the action of the counterweight 53. This prevents fluid under pressure from entering the chamber 43 and thus the main valve again remains closed to prevent filling.

If the unit has functioned properly so as to permit the filling operation to begin but a defect or malfunc' tioning developsv during the filling, operation, the main valve again will be automatically caused to closev so as. to prevent overfilling and possible bursting of the tank. Thus, for example, if the diaphragm. 25 should rupture during the filling operation, fluid will again pass from. the chamber 43 through the ruptured diaphragm andthe pressure will become balanced on. both. sides of the diaphragm, causing the main valve to close and. stop further filling of the tank.

Ln-- another example, suppose the counterweight 53 breaks off or that the float 50 becomes logged during the filling operation. In either event the weight of thefloat 56 would cause it tomove downward and shift the pilot valve to the position shown in Figure 3, thus cutting off the flow of fuel through the passage 431 and permitting the chamber 43 to become vented to the interior of the tank. The consequent loss of pressure in the chamber 43- will again permit the main valve to close to prevent further filling.

In still another example, suppose that during the filling operation the float 50 should break off either before or after the proper level of fluid has been reached- In either event, the counterweight 53 will immediately cause the pilot valveto be shifted to the iightward position as shown in Figure 2 and cause the mainvalve to close to prevent further filling.

It is obvious that minor changes in the details of construction may be made without departing from the spirit of the invention in the appended claims.

I claim:

1. A filling attachment for tanks comprising a housing having a filling opening surrounded by a valve seat, a main valve disposed on the intake side of said seat and opening against the fuel pressure when filling, a chamber above said valve having a diaphragm forming one side wall thereof, a connection between the diaphragm and said main valve, a pilot valve including a casing having a central bore in which is located a valve stem having lands thereon, said housing having a passage connecting said chamber to the bore in the casing, said housing having a by-pass conduit leading from the interior of the housing below the valve to the bore in said casing, said lands being so disposed on said valve stem that in one position the conduit will be connected to said chamber and in a second position the connection of the conduit to the chamber is closed and a connection established between the chamber and the tank so as to release the pressure in the chamber, a float connected to said pilot valve stem for shifting the pilot valve to the said closed second position when the tank is filled to a predetermined degree, a spring actuated device for shifting the pilot valve to a second closed position when the fuel supply is cut ofi, and a spring for shifting the pilot valve to open position when fuel under pressure is delivered to said housing and said spring actuated device is retracted by pressure of the fuel.

2. A filling attachment for tanks comprising a housing having a filling opening surrounded by a valve seat, a main valve disposed on the intake side of said seat and opening against the fuel pressure when filling, a chamber above said valve having a diaphragm forming one side wall thereof, a connection between the diaphragm and said valve, a pilot valve including a casing having a central bore in which is located a valve stem having lands thereon, said housing having a passage connecting said chamber to the bore in the casing, said housing having a by-pass conduit leading from the interior of the housing below the valve to the bore in said casing, said lands being so disposed on said valve stem that in one position the conduit will be connected to said chamber and in a second position the connection of the conduit to 7 d the chamber is closed and a connection established between the chamber and the tank so as to release pressure in the chamber, a float connected to said pilot valve stem ,for' shifting the pilot valve to release, pressure in said chamber when the tank 'isfilled to a predetermined degree, said housing having an extension providing, a second bore connected totsaid conduit, a reciprocating pilot valve I shifting device disposed insaid last mentioned bore and normally held in retracted position by the pressure of the fuel in the conduit, a spring in saidtbore for advancing said shifting device when the fuel pressure is cut off for movingthe pilot valve to a second closed position, and a second spring in the casing engaging the opposite end of the valve stem to return the pilot valve to open position when fuel is again supplied to the housing and the shifting device thereby retracted.

3. A filling attachment for tanks comprising a housing having a filling opening surrounded by a valve seat, a

main valve disposed on the intake side of said seat and opening against'the fuel pressure when filling, a chamber above said valve having a diaphragm forming one side wall thereof, a connection between the diaphragm and said valve, a pilot valve including a casing having a central bore in which is located a valve stem having lands thereon, said housing having a passage connecting said chamber to the bore in the casing, said housing having a by-pass conduit leading from the interior of the housing below the valve to the bore in said casing, said lands being so disposed on said valve stem that in one position the conduit will be connected to said chamber and in a said housing having an extension providing anotherrbore connected to said conduit, a reciprocating pilot valve 7 shifting device disposed in said last mentioned bore, and

having a stem adapted to make freev abutment contact with said pilot valve, said shifting device being normally held in retracted position by the pressure ,on the fuel in the conduit, a spring in said bore for advancing said shifting device when the fuel pressure is cut off for moving the pilot valve to another closed position, and a second spring in the casing engaging the opposite end of the valve stem to return the pilot valve to open position when fuel is again supplied to the housing and the shifting device thereby retracted.

References Cited in the file of this patent UNITED STATES PATENTS 1,205,898 Jones Nov. 22, 1916 1,302,538 Gulick May 6, 1919 2,007,048 Goodwin July 2, 1935 2,060,723 Brisacher Nov. 10, 1936 2,130,611 Burdick Sept. 20, 1938 2,178,866 Thomas Nov. 7, 1939 2,240,102 Textor Apr. 29, 1941