US 2529329 A
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J. H. DE F REES SAFETY TANK CLOSURE Nov. 7, 1950 INVENTOR. JOSEPH H. DEFREES BY $4M M Mom ATTORNEYS 0E dmvwvww mm mm Filed July 751 I948 Patented Nov. 7, 1950 UNITED STATES PATENT OFFICE 2,529,329 SAFETY TANK CLOSURE Joseph H. De Frees, Warren, Pa.
Application July 31, 1948, Serial N 0. 41,790 3 Claims. (01. 2204.4)
This invention relates to safety tank closures, and more particularly to a combined vent valve, fill, and manhole cover for mobile gasoline tanks, such as are used upon delivery trucks.
One object ofthe invention is to provide a combined closure of the character described, in which all parts are carried by a plate or disc attachable directly to the metal shell of the tank itself, without the interposition of a sleeve or ring between the two, enabling all necessary securing parts, such as the nuts or attaching bolts, to be mounted exteriorly of the gasolinecontaining chamber, thereby avoiding any possibility of accident as the result of tool manipulation within the tank chamber at a time when explosive gases might be ,contained therein.
A further object of the invention is to provide a combined closure of the character described, including all necessary vent or relief means for the flow;of air or gas either inwardly or outwardly through the closure, and at both low and high pressures, soas to take care of eventualities resulting fromvariations in pressure either internally or externally of the tank, as well as danger arising when the tank tips over, or from similar causes. I
Another object of the'invention is to provide a combined closure of the character described, including a small vent valve unit, capable of convenient replacement and repair, attached to a filling opening closure, the latter of which provides for maximum emergency vent relief in cases where the pressure within the tank suddenly rises to an abnormal degree as in case of fire.
Finally, another object of the invention is to provide a combined closure of the character described, which is simple, efiective and durable in operation, which can be made and applied at low cost, which is capable of manipulation without special tools or appliances, and which safeuards the tank and its contents from most of the usual hazards encounterd in vehicles of this kind.
Further objects of the invention in part are obvious and in part will appear more in detail hereinafter.
In the drawings, which represent one suitable embodiment of the invention,
Fig. 1 is a plan view, illustrating one-half of the cover, of which the omitted half is a duplicate; r
Fig. 2 is a sectional elevation on the line 2-2, Fig. 1, the vent valve being shown in elevation;
Fig. 3 is a detailed section, on a larger scale, on the line 33, Fig. 2; and
Fig. 4 is a detailed sectional plan view on the line 44, Fig. 3.
The tank to which the closure forming the subject matter of the present invention is applied, indicated at I0, may be of any suitable form or description and is usually made of heavy sheet metal, of the order of one-eighth of an inch in thickness, the tank as a whole being elongated and of circular or oval crosssection.
The closure of the present invention includes a base disc or plate I l, of circular or oval form, a little larger than an opening l2 in the tank wall which it covers. Thus, the peripheral portion of the plate ll overlaps the edge of the opening [2, the overlapping portions of the cover and tank being sealed by a ring-form corkor other suitable gasket I 3. Base plate H is secured to the tank wall by a series of bolts I4, spaced peripherally around the opening and suppliedwith adjustable clamping nuts 15" and sealinggasket l6, preferably'copper covered asbestos gaskets, and with lock washersll. Thus, at each bolt the cover and body are firmly and tightly clamped and sealed'together, preventing any possible leakage.
At any time, by taking. off thenuts IS, the plate H and all parts supportedby'it may be taken of; from the tank, the large ,opening l2 serving as a manhole for accessto its interior. By opening the filling opening later described, access may be had to the heads of bolts M to prevent them from falling into the tank cavity, but removal of the closure involves no" tool manipulation within the tank chamber, such as might cause a spark and ignite inflammable gases and cause an explosion.
The central portion of base plate H isprovided with a large filling and vent opening l8, around which the plate is turned up to form a generally cylindrical short neck or wall [9 fianged'inwardly at 20. Flange 20 is formed in a uniform fiat plane'even though the plate I I must be curved to correspond to the contour of the wall In of the tank itself.
Adjacent to and outside of the wall Hi, the cover plate is provided with two pairs of upstanding ears, 20 at the left in Fig. 2 and 2| at the right. Ears 2i pivotally support a cross bar member 22, to the undersurface of which is secured a vent valve unit, marked generally 23 and later described in detail. The far end of bar member 22 is provided with a shoulder 24 and beyond it' with a curved tongue or extension 25.
Cooperating with bar 22 .is a looking or latch lever 2 6-pivota11y connected to the ears 2!! and having a recess or opening 21 through which the tongue 25 of bar 22 extends, when the parts are in closed position, and also havinga transversely extending shoulder or abutment 28,
- adapted, in closed position of the parts, to engage the shoulder 24 and "thus 'releas'ably lock or latch the bar 22 in cover-closed position.
The undersurface of bar 22 is provided with a. hollow central boss 30 having several lateral openings 3|. This boss isinternally threaded to receive the threaded portion of the vent valve unit 23. The head of thevent valve unit clamps in place a disc valve or gasket member 32 backed by a steeldisc diaphl'agm33, below whlchis cated a gasket retaining disc 34, spaced from gasket 32 by a spacing washer 35. l
The vent valve unit is shown in detail in Figs. 3 and 4. It comprises a body portion 36 threaded at 31 for securement to the boss -3t) and provided with a noncircular or hex head 38. Body 36 is hollow and is provided internally with several, four being shown, of internal longitudinal ribs 39 which form guides along which slides a poppet valve member 40 biased upwardly in Fig. 3, against an annular seat 4| by a light compression spring 42.
The central portion of the poppet valve is of tubular form, the chamber therein, being provided with an upper ball valve member 43 seating downwardly, and with a lower ball valve member 431; normally inactive and supported by an imperforate closure disc. The upper end of the chamber'is provided with a'disc 45 provided through ports or openings 45.' 41 indicates a series of several small lateral relief ports or openings in the lower portion of the central body of the poppet valve member.
Figs. 2 and 3, together, illustrate the normal positions of all parts when, the cover is fully closed, such as when the vehicle is traw n along x V the road. Movement of latch lever 23 22 soas to app y the sealing disc froingasket32 to the flange with yielding jpressure, although the bar 22 has not beendepre'ssed sufiiciently to contact with the backing plateior disc 33. Spring 42 holds the poppet valve elevated and in closed position. Ballvalve 43 is. at rest closing the channel beneath it, while ball valve 43a is also at restupon imperforat'edisc'fl. t Shouldf'the pressure within the tankrise a small-amount, say one poundon so, for any reason, relief of the pressure tqatmosphereis afforded by way of the .vent valve, through ports 41, and then upwardly-around ball 43, which it unseats, thencethrou'gnports and 3| and out to atmosphere around, -the bar 26. I -lowever, should the. pressure within thetank rise abnormally, say about six, seven or more pounds, then the backing disc'33yieldsand .allows gasket 32 to rise away from the flange 2D and open a wide vent around the disc-like gasket directly to atmosphere. Y I
Should the pressure within the tank fail, spring 42 yields and permits the poppet valve as a whole to move downwardly in Fig. 3, air then flowing inwardly through ports 3| and downwardly around the outside of the poppetvalve in the spaces between the ribs 39 and thence to the interior chamber. 4
Should the truck turn over, so that the vent valve is upside down, or partially so, so that ball 43 is below ball 43a, then ball 43a moves to a seat at the opposite end of its chamber, closing off the ports 41 and preventing loss of liquid through the vent valve' However, if with the parts in this positioniventing inwardly neces-. sary,- the valve 'spiing12'agaitryields. permitting the poppet valve to move inwardly and .opena the latching position shown'has depressed the bar passage as before. Likewise, if; the pressure in i the .overturned tank arises abnormally, such as because of fire, the large. disc '33 yields-and opens the larger vent-to thefoutsidegas before. l
The constructiondescribed not onlyprovides for, all, necessary safeguarding vents, both in wardly .andfloutwardly butwalso provides a. tank closure-that requires no attachmentof-a or flange to thetank itself, and entirely dispenses with tool work on' the inside of the tank when removing or re-applying the closure thereto, thus avoiding accident.
Other advantages of the invention will be apparent to those skilled in the art.
What I claim is:
1. A combined vent valve and filling and manhole cover for mobile gasoline tanks, comprising a sheet metal base adapt-ed for attachment of its peripheral portion to the metal around an opening in the tank wall, said plate being provided with an opening of relatively large diameter, an arm pivoted on said plate at one side of the opening therein and extending across said opening and provided at the center thereof with a recessed internally threaded boss, a cover for the tank wall opening seated upon said boss, and a generally cylindrical externally threaded vent valve unit extending through a central, opening in said cover and threaded into the recess of said boss and having a shouldered head which secures the cover to the boss.
2. A combined vent valve and filling and manhole cover for mobile gasoline tanks, comprising a sheet metal base adapted for attachment of its peripheral portion to the metal around an opening in the tank wall, said plate being provided with an opening of relatively large diameter, an arm pivoted on said plate at one side of the opening therein and extending across said opening and provided at the center thereof with a recessed internally threaded boss, a cover for the tank wall'opening' seated upon said boss, a generally cylindricalexternally threaded vent valve unit extending through a central opening in said cover and threaded into the recess of said boss and having a shouldered head which secures the cover to the boss, said vent valve unit including a tubular body portion, and a yielding valve member seating outwardly and mounted within the bore thereof.
, 5 3. A combinedvent valve and filling and manhole cover for mobile gasoline tanks, comprising a sheet metal base adapted for attachment of its peripheral portion to the metal around an opening in the tank walLsaid plate being provided with an opening of relatively large diameter, an arm pivoted on said plate at one side of the opening therein and extending across said opening and provided at the center thereof with a recessed internally threaded boss, a cover for the tank wall opening seated upon said boss, a generally cylindrical externally threaded vent valve unit extending through a central opening in said cover and threaded into the recess of said boss and having a shouldered head which secures the cover to the boss, said vent valve unit including a tubular body portion, a yielding valve member seating outwardl and mounted within the bore thereof,-and having a through passage, and two yieldable check valves, one seating outwardly and the other inwardly; carried by said valvemember, and mounted in the through channel thereof.
r JOSEPH H. DE FREES.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,739,911 McMurray Dec. 17, 1929 1,893,942 Jensen Jan. 10, 1932 2,089,251 De Frees 'Aug. 10, 1937 2,169,410 Drane Aug. 15, 1939