US2757819A

US2757819A - Closure device for tanks

Info

Publication number: US2757819A
Authority: US
Inventors: Jr Everett H Badger
Original assignee: Parker Appliance Co
Current assignee: Parker Appliance Co
Priority date: 1950-09-07
Filing date: 1950-09-07
Publication date: 1956-08-07
Anticipated expiration: 1973-08-07

Description

g- 7, 5 E. H. BADGER, JR

CLOSURE DEVICE FOR TANKS Filed Sept. 7, 1950 INVENTOR.

1: was 77 6f 619E669, JR. BY

United States Patent CLOSURE DEVICE FOR TANKS Everett H. Badger, Jr., Euclid, Ohio, assignor to The Parker Appliance Company, Cleveland, Ohio, a corporation of Ohio Application September 7, 1950, Serial No. 183,547

9 Claims. 01. 220-40 The present invention relates to closure caps for tanks and is more particularly concerned with a cap for closing an opening at the bottom of a tank through which the tank may be periodically filled or drained.

It is rapidly becoming the practice to furnish airplanes of particular types with underneath refueling systems. In such systems the fuel tanks may be filled or drained from an opening in the bottom of the tanks or from an opening in a manifold which leads to several tanks where the opening is at a point lower than the level of the tanks. The opening is usually formed in a housing which is permanently attached to the tank or manifold. The housing is provided with means whereby a nozzle for either filling or draining the tank may be conveniently attached and includes a valve, usually in the form of a spring closed check valve, for closing the opening when the nozzle is detached. Because of the great hazard incidental to any leakage of fuel past such a valve it is desirable to provide an additional means for sealing the opening as an added precaution against leakage. Such additional means has been provided by the applicant in the form of a detachable closure device which also acts as a protective means to prevent the accidental opening of the valve and to prevent damage to and the lodging of foreign matter upon the exterior portion of the housing.

It is an object of the present invention to provide a removable closure device for a valve-closed opening in the bottom of a tank or manifold in which the closure device has a seat portion and an expansible pressure chamber associated therewith whereby leakage fluid within the opening will have access to the pressure chamber and will urge the seat portion into tight engagement with a sealing surface surrounding the opening.

It is another object to provide a closure device of the type described in which the device has a seat portion urged by a spring into engagement with a sealing surface about the opening to be closed and in which means is provided for utilizing fluid pressure within the opening for augmenting the force of the spring.

It is another object to provide a closure device for the opening in the bottom of a tank in which the device has a fluid pressure seated portion adapted to nonrotatably engage a sealing surface about the opening and in which the device has another part rotatable with respect to the fluid pressure seated portion for attaching the latter to the bottom of the tank.

It is another object to provide a closure device for an opening in the bottom of a tank in which the device has a rigid closure plate attachable to the tank at a fixed distance from a sealing surface surrounding the opening and in which an extensible means is attached to the plate and carries a seat portion with which an effective area is associated whereby fluid pressure within the opening will act on the area to urge the seat portion into tight engagement with the sealing surface.

It is another object to provide the combination of a housing and a closure device in which the housing has means for attachment to the bottom of a tank and has a valve closed opening surrounded by a depending tubular skirt and wherein the closure device includes an extensible seat carrying member located within the tubular portion and having means whereby fluid pressure within the opening will tend to extend the extensible member for urging the seat into tight sealing engagement with the sealing surface of the housing.

It is another object to provide a closure device of the type described which includes one part for closing the opening in the bottom of a tank and another part for attaching the first part to the tank and in which fluid pressure may be transmitted through non-yielding means to the second part for helping prevent accidental detachment from the tank.

Other objects of the invention will become apparent from a more detailed description and from the drawing in which:

Figure 1 is a plan view of the closure device as attached to a housing at the bottom of a tank wherein the view of the housing is along the lines 1 -1 of Figure 2.

Figure 2 is a longitudinal sectional view through the closure device as attached to a valve-closed housing at the bottom of a tank.

Figure 3 is a fragmentary sectional view taken along the lines of 33 of Figure 1 and showing the means for preventing accidental detachment of the closure device from the tank housing.

The closure device is generally indicated by the numeral 10 and is adapted to be attached to a housing 11 which in turn is secured to the bottom wall 12 of a tank by suitable bolts 13. Alternatively, the housing 11 may be secured to or be an integral part of a suitable manifold, not shown, which in turn may lead to one or more tanks.

In the invention as illustrated the housing 11 has a tubular skirt portion 14 attached thereto by screws 15. The tubular portion includes an opening 16 surrounded by a flanged portion 17. The upper surface of the flange 17 provides a seat for valve 18 which is supported by spaced ribs 19 and which is normally urged toward closed position by the spring 20.

The flange 17 is spaced a distance inwardly of the bottom end of the tubular skirt 14 and the lower face of the flange provides a sealing surface engageable by a gasket or seat portion 21 associated with the closure device 10. The lower end of the tubular skirt 14 is provided with spaced outwardly directed bayonet lugs 22 which serve as an attaching means for the closure device.

The housing 11 is preferably recessed as at 23 where by the closure device may be completely contained within the recess so that its outer surface 24 will be substantially flush with the bottom wall of the tank.

The closure device 10 includes a circular closure plate 30 at the outer margin of which an extensible metal bellows 31 is sealingly attached as by brazing. The metal bellows 31 is of tubular form and has flexible corrugv tions 32 which permit ready lengthening and shortening of the bellows in the well known manner.

The other end of the bellows is attached by brazing, or any other suitable method, to the outer margin of a circular disk 33. Also mounted at the outer margin of this disk is a rubber-like sealing gasket 21. The gasket 21 is retained upon the disk 33 by a metal ring 34.

The disk 33 has a depression 35 in its central portion and has aseries of perforations 36 between this depressed portion and the outer margin. At the center of the disk there is a .hole 37 through which a pin 38 is inserted and held in place by means of a snap ring 39. The pin 38 also passes through a hole in the center of the closure plate 30 and is brazed thereto as at 40, the braze serving to seal the connection as well as to unite the two parts integrally. The lower end 41 of the pin passes through a bearing ring 42 and an attaching cap 43, the latter being retained by a snap ring 44. The snap ring 44 is located within a depression 45 in the attaching cap 43 and a cover plate 46 extends across the recess 45 to cover the pin and to present a smooth flush surface on the outside face of the cap. The lower end 41 of the pin is a slip fit within the hole through the cap so that the latter may be readily rotatable upon the pin. A spring 47 extends from the closure plate 30 to the disk 33 and tends to separate the same. The snap ring 39 limits the amount which the two parts can be separated.

Toward the outer margin of the inside surface of the cap 43 there is an annular shoulder 50. Mounted on this annular shoulder is a retainer ring 51 having spaced inwardly directed lugs 52, the retaining plate being attached to the cap 43 by the screws 53.

Inwardly of the shoulder 50 and passing beneath the lugs 52 there are a series of inclined surfaces 54 formed in the cap 43. Between adjacent pairs of the inclined surfaces 54 are vertical abutment shoulders 55. These abutment shoulders are located beneath the lugs 52 and serve as stops against which the bayonet lugs 22 abut when the closure device is attached to the housing 11. One of the lugs 52 has an edge bent downwardly as at 56 for preventing accidental rotation of the attaching plate 43 in a direction for detachment from the bayonet lugs 22.

The outer face of the cap 43 is provided near its outer margin with two pairs of diametrically spaced depressions 60 so arranged that there is a web 61 between each pair. This provides a means for grasping and turning the plate with the fingers when attaching or detaching the closure device from the housing. A chain 62 has one end attached to one of the screws in the housing and the other end to one of the screws 53 so that the closure de vice will not be accidentally mislaid while detached from the housing 11.

When the closure device is attached to the housing 11, the closure plate 30 will overlie the abutment in the tubular skirt 14 and will be spaced a fixed distance from the lower sealing surface of the flange 17. The initial unstressed length of the metal bellows 32 is such that the upper face of the gasket 21 is normally spaced from the closure plate a distance which is greater than the distance from the plate 30 to the sealing surface 25. Thus the bellows 32 is slightly compressed in length when the closure device is attached to the housing. This causes the gasket 21 to be pressed against the sealing surface 25 by an amount of force dependent upon the tendency of the bellows 32 to resume its normal length plus an amount determined by the spring 47. In order to accommodate sealing deformation of the gasket 21 and also to accommodate slight variations in the distance from the closure plate 30 to the sealing surface 25 due to manufacturing variations, the disk 33 may move axially upon the pin 38 between the snap ring 39 and the opposed abutment shoulder 48, the snap ring limiting the distance the disk 33 may move away from plate 30 and the shoulder 48 limiting the distance that it may move toward the plate.

The metal bellows 32 and the closure plate 30 form a pressure chamber which is in communication with the opening in the housing by virtue of the perforations 36 in the disk 33. The outer diameter of the metal bellows is greater than the diameter of the contact line between the gasket 21 and the seat 25. This provides an effective or differential area determined by the two diameters mentioned. Fluid pressure within the bellows acting upon this differential area is effective for urging the gasket 21 into tighter sealing engagement with the sealing surface 25. Thus fluid pressure within the pressure chamber formed by the bellows and the closure plate 30 will augment the force of the spring 47 and of the bellows for seating the gasket 21. When the housing 11 is provided with the valve 18 there will normally be no fluid within the housing opening 16 below the valve nor within the bellows. But if the valve 18 fails to seat tightly leakage fluid fills the bellows and acts upon the differential area with a pressure determined by the head of the fluid within the tank, or in the case of pressurized tanks or manifolds, by the pressure existing therein.

To attach the closure device to the housing 11, the cap 43 is inserted within the housing recess 23 with the lugs 52 positioned intermediate the lugs 22 on the tubular skirt. At the same time the bellows portion 32 is in serted within the tubular skirt until the gasket 21 contacts the sealing surface 25. The cap 43 is then rotated in a clockwise direction causing the lugs 22 and the tubular skirt to ride down the incline surfaces 54 until they abut the vertical stop shoulders 55. As this time the lugs 22 will be underneath the lugs 52 for retaining the closure device in place. Because of the loose connection between the lower end 41 of the pin and the cap 43, the latter will rotate with respect to the pin during attachment and detachment and no rotary movement will be imparted to the bellows or to the gasket 21.

Pressure from the spring 47 and from fluid within the bellows acts directly through the plate 30, bearing ring 42 and attaching plate 43 for biasing the lower face of the lugs 52 into engagement with the upper faces of the lugs 22. The downwardly turned end 56 of one of the lugs 52 makes it necessary to raise the cap 43 a slight amount in order to remove the latter by reverse rotation. Such raising is resisted directly by the spring and by the pressure of fluid against the plate 30 and thus the downwardly turned end 56 acts as a stop to prevent accidental unloosening or detachment of the closure device.

Although but one embodiment of the invention is illustrated in the drawing, it is understood that many minor variations in the shaping or arrangement of the parts will be embraced by my invention as defined by the following claims.

I claim:

1. A closure device for a housing having an opening surrounded by a sealing surface, comprising a closure plate, means associated with the plate for attaching the same to the housing, an extensible tubular bellows attached at one end to the plate and forming therewith a pressure chamber, an annular seat portion at the other end of the extensible bellows and engageable with the sealing surface, the internal diameter of the outer wall of the bellows being greater than the diameter of said seat so as to provide a transverse wall portion within the bellows between the seat and said outer wall, said wall portion being subject to the pressure of fluid within the chamber for urging the bellows toward an extended position with the seat in tight contact with the sealing surface.

2. A closure device for a housing having an opening surrounded by a sealing surface, comprising a closure plate, means associated with the plate for attaching the same to the housing at a fixed distance from the sealing surface, an extensible tubular bellows attached at one end to the plate and forming therewith a pressure chamber, an annular seat portion at the other end of the bellows and engageable with the sealing surface, the bellows being of such length compared to said fixed distance that it will be slightly compressed to initially press the seat portion into engagement with the sealing surface when the plate is attached to the housing, the internal diameter of the outer wall of the bellows being greater than the diameter of said seat so as to provide a transverse wall portion within the bellows between the seat and said outer wall, and an opening in the chamber whereby when the plate is attached to the housing fluid within the housing opening will have access to the chamber and act upon the transverse wall portion to urge the seat portion into tighter seating engagement with the sealing surface.

3. A closure device for a housing having an opening surrounded by a sealing surface, comprising a closure plate, means associated with the plate for attaching the same to the housing, a disk having an annular seat portion engageable with the sealing surface, extensible means connecting the outer margins of the plate and disk and forming therewith a pressure chamber, perforations in the disk whereby fluid in the opening of the housing has access to the chamber when the plate is attached to the housing, said extensible means including a transverse wall within the chamber, said wall projecting radially outwardly of the seat portion and being subject to the pressure of fluid within the chamber for urging the extensible means toward an extended position with the seat in tight engagement with the sealing surface.

A closure device for a housing having an opening surrounded by a sealing surface, comprising a closure plate, means associated with the plate for attaching the same to the housing, a disk having an annular seat portion engageable with the sealing surface, extensible means connecting the outer margins of the plate and disk and forming therewith a pressure chamber, perforations in the disk whereby fluid in the opening of the housing has access to the chamber when the plate is attached to the housing, said extensible means including a transverse wall Within the chamber, said wall projecting radially outwardly of the seat and being subject to the pressure of fluid within the chamber for urging the extensible means toward the sealing surface, a spring between the disk and plate constantly tending to separate the same, and a stop for limiting the amount which the plate and disk can be separated.

5. A closure device for a housing having an opening surrounded by a sealing surface, comprising a closure plate, means connected with the plate for attaching the same to the housing, a disk having an annular seat portion engageable with the sealing surface, extensible means connecting the outer margins of the plate and disk and forming therewith a pressure chamber, perforations in the disk whereby fluid in the opening of the housing has access to the chamber when the plate is attached to the housing, said extensible means including a transverse wall within the chamber, said wall projecting radially outwardly of the seat portion and being subject to the pressure of fluid within the chamber for urging the extensible means and the disk toward the sealing surface, a spring between the disk and plate constantly tending to separate the same, and :a pin connecting the disk to the plate and having means for permitting limited separating movement therebetween.

6. A closure device for a housing having an opening surrounded by a sealing surface, comprising a closure plate, a cap connected to the plate and having means for attachment to the housing, a disk having an annular seat portion engageable with the sealing surface, extensible means extending from the plate to the disk and forming therewith a pressure chamber, a passage to the chamber whereby fluid in the opening of the housing has access to the chamber when the plate is attached to the housing, said extensible means including a transverse wall within the chamber, said wall projecting radially outwardly of the seat :and being subject to the pressure of fluid in the chamber for urging the extensible means and the disk toward the sealing surface, a pin connecting the disk, plate, and cap, said pin having means for permitting limited endwise movement of the disk relative to the plate.

7. A closure device for a housing having an opening surrounded by a sealing surface, comprising a closure plate, a cap connected to the plate and having means for attachment to the housing, a disk having an annular seat portion engageable with the sealing surface, extensible means extending from the plate to the disk and forming therewith a pressure chamber, a passage to the chamber whereby fluid in the opening of the housing has access to the chamber when the plate is attached to the housing, said extensible means including a transverse wall within the chamber, said wall projecting radially outwardly of the seat and being subject to the pressure of fluid in the chamber for urging the extensible means and the disk toward the sealing surface, a pin connecting the disk, plate, and cap, said pin having means for permitting limited endwise movement of the disk relative to the plate and also having means for permitting the cap to be rotated with respect to the plate when the cap is being attached to the housing.

8. In combination, a housing having an opening surrounded by a sealing surface and having attaching lugs, a closure plate, a pin permanently connected to the closure plate, a capconnected to the pin and having means engaged with the lugs for attaching the closure plate to the housing, a spring normally biasing the cap into tight engagement with the lugs, an extensible bellows connected to the closure plate and forming therewith an expansible pressure chamber permanently closed at one end, said bellows having a seat portion engageable with the sealing surface, and also having a transverse wall portion of greater diameter than the seat portion whereby fluid pressure within the chamber will act on the wall portion to move the seat portion into tighter engagement with the sealing surface, said chamber having an opening at its other end whereby fluid within the housing has access to the chamber and may act on said closure plate, and non-yielding means for transmitting the pressure of the fluid acting upon said closure plate to the lugs.

9. In combination, a housing having an opening surrounded by a sealing surface and also having a tubular skirt extending outwardly of the sealing surface and provided with spaced lugs, a closure plate, means associated with the plate cooperable with the lugs for attaching the plate to the housing in a position across the opening and spaced a fixed distance from the sealing surface, a disk within the tubular skirt and having an annular gasket at its outer margin, an extensible bellows within the tubular skirt and sealingly attached to the outer margins of the plate and disk and forming therewith a pressure chamber, a pin connecting the plate and disk and having means for permitting the gasket to be moved toward or away from the plate from a distance shorter to a distance longer than the fixed distance, yieldable means tending to elongate the bellows and biasing the gasket into engagement with the sealing surface, a passage to the chamber whereby fluid in the opening has access to the chamber, the internal diameter of the bellows being greater than the diameter of engagement between the gasket and the sealing surface so as to provide an area associated with the bellows lying between the engagement of the gasket and sealing surface and the outer wall of the bellows, said area being subject to pressure of fluid within the chamber for urging the bellows toward an extended position with the gasket in tight engagement with the sealing surface.

References Cited in the file of this patent UNITED STATES PATENTS 1,665,827 Tillman Apr. 10, 1928 2,102,962 Ludington Dec. 21, 1937 2,133,934 Ericsson et a1. Oct. 18, 1938 2,195,266 Bailey Mar. 26, 1940 2,225,964 Bailey Dec. 24, 1940 2,394,911 Griswold Feb. 12, 1946 2,581,536 Johns Jan. 8, 1952 FOREIGN PATENTS 571,655 Great Britain Sept. 4, 1945