US2852169A - Safety release device for tanks - Google Patents

Description

Sept. 16, 1958 D. A. KIFFER ETAL 2,852,169

SAFETY RELEASE DEVICE FOR TANKS Filed Sept. 26, 1955 2 Sheets-Sheet 1 llllllili- AWHZ UPE A 5/85 A. AIFFER ZAWRENCE 0 255;

Sept. 16, 1958 D. A. KIFFER ET AL 2,852,169

SAFETY RELEASE DEVICE FOR TANKS Filed Sept. 26, 1955 2 Sheets-Sheet 2 0/2. K M 3 :H S L F E 1 7 45 W T D U M E5 w Fm T. W ,0 A 5 Z 3 partly broken'of ap'ortiornof-the'spraytank "illustrating the instant invention;

United States PatentO SAFETY RELEASE DEVICE FOR TANKS -Desire A; Kilfer," Waterlooyandliiawrence DI-Ors'er,

Cedar Falls,ilowa,'assignors to. Ghainberlain Corporation, Waterloo,rlowa, a-corporation of Iowa .Application September 26,".1955, Serial No. 536,423

.- 8 Claims. (Cl.:-2 22-;-. 396) on a flame sprayer or weed burner, it obviously can be .used on other spray tanks and on many otherftypes of pressure tanks.

-Heretofore, in the usefof flame sprayers having a spray tank, it was sometimes a hazardous operation inasmuch as a lackadaisical user, insteadr otbuildingupthepressure in the spray tankicontainingw the inflammable liquid by use of the-usual hand pumpgdirectedithelflame from the burner jagainst the sidejofsthe tank toincrease' the pressure by raising the. temperature 'of..the..inflammable 1iquid; Such amethodiof raising-[the .tank pressure is dangerousin that extreme. pressure is. built up in a short 7 .period of time which cannot be withstood by..the .tank

thereby causing the spray tankto blow..up,..and.in the past this has caused grave. injuryandsometimes death to a. user. 7

T In the present invent-ion, a safety release device is.associated with a spray tankwhichperrnits the top. or cover of the spray tank to raise up when a. predetermined pressure isdeveloped in the tank and. a1l0w.;the excess of i that pressure to escape' Under actual tests, it was. found impossible. to blow-up a spraytankrequipped with:.this

device.

' Accordingly, it is an objectofthis inventionv to.pro-

vide an. improved spray tank for handling..inflammable liquids that will not blow up under any. circumstances.

Another object of this invention is to provide a safety 1 release device for pressure tanks that isefiective. torelieve against, extremely sudden variationsin,pressure-. as well as steady pressure rises.

A further object of this invention. residesin .the. provision of a. spray tank. havingmeans topermit'the top or coverof the .tank to raisenp when a predetermined pressure is, developed in. thetankand allow .the excess of that pressure to escape.

. Afurther feature ofthis invention is. toprovide asafety release device foruse. on spray. tanks. and to-bemounted .inthe top lockassembly. that doesnot. occupy any. notice- ,ableadditionalspace over. and above thespace. required .forconYentionaLtop lock assemblies heretofore.

While someofthe. more. salient features, ..characteris- .tics... and advantages ofthe. instant. inventionhave. been .above pointed out, .others willabecome apparent from the .following disclosures,.taken inconjunction with the accompanying drawings, in-which:

- .Figure lis a; broken elevationalview of a flamesprayer equipped with the present invention;

' Figure 2 is' an elevational view,- partly; in section .and in'Figure 1 Patented Sept. 16, 1958 ice "Figure 3 is atop plan view ofthe spraytank with the cover assembly and burner. assembly removed. therefrom; and

"Figure 4 is a top plan view'of thejpurnp handle locking :means, taken substantially along' linein? Figure 2 and looking in the directionofi the arrows.

As shown on the drawings; Referring generallyqtoi'lf'figuree l, af' flame .sprayer equipped with the present invention is" illustrated com- .prisinggenerally a conventional cylindrical- ,tank ;10, a

-. conventional burner/assembly 11 connected to the ,tank

'10 by a flexible tubing'.11a,.a'nd aacover assemblyin inwhich is mounted. the Isafetyrelease m'echanismfofi the v. instant invention. e

. A'strap. assembly 13 is: connected. al'.=,0n6..1id near. .the top of the tank'ltl'and at the other end near the,,bottom thereof for: facilitating. transporting, of: the .sprayeizl'from placetoplace.

iThevt'ank 10 is closed. atone end. and initially. open at. the other..end.befoIeJfinaLaSsembIy.. .Ahead 14 is sealingly secured, such asby weldingorother' equivalent means to the open end oi the tank' 10.

As seen most clearly in Figure'Z, the head..14 is. in

....the,general .form. of .an. annulus. having .a radially inwardly ...ex tendingrflange 15..l.Before the flangef-li. is rolled, a

., ,camring. -16... havingsan annular. 'flange portion- 16a is ,spoLw'eldedto the. head. flhensthefiangerli is..rolled ...over the 3 upper: surface. and .ma'rginal Ledge. ofsthesflange .portion 16a. .zAsi'seen in:Eigure2nan openingl4a is .prov-ided: in. the. head 14 foraconnection ';to.. the. burneras- ...sembly.

..:C.onnecting vwith. theannular.portionlfia. of; the...carn

,ring .16, is a substantially. vertical. cylindricalportion.:16b

. ing section 16c.

which, in turn, merges with achannel-shaped coverv lock- The upper legof thechannel-shaped section-16c. is. .bayonet slotted ;at. 16d asaseenn. in Eigure 3,. and the-sections of the legbetween the slots are slightly 7 inclined;- from. one end :of .the..section.:to. theuothercend tovprovide aconvent-ionalcammingarrangement.

.The..coverassembly; 12 includes a dishashaped. lid. 17

. having an annular. lip18 connected .to. the. uppermarginal .-.edge.and .sized. to.be substantially..diametrally'larger than sthemfiange- 15.v Av ring-shaped .gasket. or. seal .19 of any suitable resilient..material. iswfitted on vthe. underside. of

.zthe .;lip ,18 .toaccommodate. sea-ling..engagemenhbetween .The. dishshaped did. 17 iscentrally; apertured :and. pro- ,vided .with an upturned annular flange; 17a "for.v receiving a -pumping. cylinderlll. The. pumping cylinder-20pxtends downwardly into the tank and is provided at. its

.bottom end with a. unidirectional valve .(not.-sho.vvn) to :al-low airflow into thetank. Theupperv end of the pumpa ing cylinderldextends slightly; above the flange opening -in .thelid 17 and terminates in amollededge, andcylinder. 20. issealingly-secured tothefiange 17a-of:.the:lid

.- 17 .in asuitable manner, such. as by welding.

"To. secure the: lid in. position, a. lid locking assembly '-or yoke includes a sleeve 21 having a pair ot'diametrically the camring 16. a Y

opposed arms-22, .22, .the ends ofwhich are received, by

.As seenrin Figure 2;.the sleeve-.21;--.is centrally-bored and receives inrthreaded engagement 1 at 23 a pump dock -.and sealing screw 24. The-.sleeveabore is diametrically enlarged at 21a and the sealing screw 24 iss'diametrically reduced at;the lowerportionasindic-ated at 24a: to define :g-an annular. chamberwor socket for-:-'receiving az-he'avy metal 1 helical-spring :25.

'lrhe springr25 surrounds zthenreduced: 'portion' 24a of :theilsealing screw 24 and is bottomed on aneannular shoulder 'of' the: sealing screw -24 provided by'- the i diametrally reducedsection and indicatd =-at 24b. The

other end of the spring is bottomed on a centrally apertured dome-shaped member 26 that is received over the extreme end of the sealing screw 24. The domeshaped member 26 functions as a pump cap and is maintained on the end of the sealing screw 24 by awasher 27 abutting against the underside of the cap, and which is held in place onthe reduced end of the sealing screw 24 by a retaining ring 28.

The force of the spring 25 is transmitted to the lid 17 through an annular flange 26a on the dome-shaped pump cap 26, and the force of the spring urges the lid 17 into sealing engagement with the flanged opening of the tank 10.

To maintain the lid 17 and pump cylinder 20 connected to the sleeve 21 and locking arms 22, a series of lugs 29 are annularly arranged and carried on the inner face of the pump cap 26 and near the lower marginal edge thereof to coact with the upper rolled edge of the pump cylinder 20 when removing the entire assembly from the tank 10.

To initially build the pressure up within the tank a hand pump is provided having a pump rod or shaft 30 slidably received in a central bore of the sealing screw 24. A plunger 31 is connected to one end of the shaft 30 and operable within the pump cylinder 29, and a pump handle 32 is connected to the other end, as seen in Figure 1.

To lock the pump handle in place on the cover assembly 12, a pair of diametrally opposed pump locking arms 33, 33 are suitably secured to the pump handle 32 and coact with a pump locking ring 34 on the sealing screw member 24. As seen most clearly in Figure 4, the pump locking ring 34 is provided with a pair of diametrally opposed slots 35, 35 for receiving the locking arms 33. The handle is locked in position by pushing down the locking arms 33 through the slots 35 and turning the handle so that the inwardly extending lugs 33a on the locking arms are positioned away from the slot 35. A pair of diametrally opposed lugs 36, 36 extend outwardly from the locking ring 34 and are in arcuately spaced relationship to the slots 35. These lugs provide abutments or stops for the locking arms 33 on the pump handle 32. To maintain the locking arm 33 on the handle 32 in tight engagement with a locking ring 34, a spring 37 surrounds the pump shaft 30 and is received in a shallow groove formed around the shaft in the sealing screw 24. The spring is bottomed in the groove at one end and engages the handle at the other end.

In the initial assembly of the cover arrangement 12, the spring 25 is preloaded to a predetermined amount to urge the lid 17 in sealing engagement with the tank flange 15. Additional loading of the spring 25 may be accomplished by turning the sealing screw member 24 down into the sleeve 21.

In operation, after the cover assembly 12 has been placed in locking engagement with the head 14 of the tank 10, pressure is initially built up within the tank against the inflammable or other liquid therein by the hand pump. If the user, in order to raise the pressure in the tank, directs the flame of the burner against the side of the tank, and the pressure rises above a predetermined amount, the lid 17 will raise against the force of the spring 25 and break the seal with the flange 15 to allow the excess pressure to escape from the tank.

' When the pressure .falls to the predetermined amount, the spring 25 will again urge the cover of the tank into closed position and prevent the escape ofall the pressure in the tank.

In view of the foregoing, it is seen that the instant invention provides a safety release device for use with spray tanks which precludes the possibility of an extreme or gradual pressure above a predetermined amount from being built up within the tank that may cause the tank to blow up and injure the user or a bystander.

' It will be understood that modifications and variations may be etfected without departing from the scope of the novel concepts of the present invention, but it is understood that this application is to be limited only by the scope of the appended claims.

We claim as our invention:

1. In a spray tank closed at one end and open at the other end, a centrally open head member secured to the open end of said tank and having an inwardly extending radial flange, a cam ring attached to said flange, a cover assembly including a lid bearing on said flange, a sleeve member having a pair of arms removably received by said cam ring, a pressure-movable dome-shaped member positioned between said sleeve and said lid, a tensioned spring means located interiorly of said sleeve biasing said dome-shaped member against said lid causing said lid to sealingly engage said flange, and screw means carried by said sleeve for adjusting the tension of said spring means, whereby pressure within said tank above a predetermined amount breaks the sealing engagement of the lid and flange and allows the excess pressure to escape.

2. In a spray tank closed at one end and open at the other end, a centrally open head member secured to the open end of said tank and having an inwardly extending radial flange, a cam ring attached to said flange, a cover assembly including a lid bearing on said flange, a sleeve member having a pair of arms removably received by said cam ring, a dome-shaped member positioned between said sleeve and said lid, a tensioned spring means in said sleeve biasing said dome-shaped member against said lid causing said lid to sealingly engage said flange, a sealing screw carried by said sleeve for adjusting the tension of said spring means, said screw having a longitudinal bore therethrough, a hand pump mounted on said cover assembly having a plunger rod slidable in said screw bore, whereby pressure within said tank above a predetermined amount breaks the sealing engagement of the lid and flange and allows the excess pressure to escape.

3. A safety release device for a pressure tank having a flanged opening and a cam ring secured thereto, which comprises a cover bearing against said flanged opening, a sleeve member overlying said cover, a pair of diametrically opposed arms integral with said sleeve and removably engaging said cam ring, a pressure-movable domeshaped member disposed between said cover and said sleeve, and a preloaded spring means located interiorly of said sleeve biasing said dome-shaped member against said cover causing said cover to sealingly engage said flanged opening, and screw means carried by said sleeve for adjusting the preload of said spring means.

4. In a spray tank closed at one end and having an opening in the other end, a retaining ring around said opening, a cover for said opening, a pump cylinder carried by said cover to extend into said tank, a cover locking member engageable with said ring, resilient means carried interiorly of said locking member, pressure-movable closure means for the cylinder in contact with the cover and resilient means to urge said cover tightly over said opening, and a pump rod extending through said member.

5. In a spray tank closed at one end and having an opening in the other end, a retaining ring around said opening, a cover for said opening, a pump cylinder carried by said cover to extend into said tank, a cover locking member engageable with said ring, resilient means carried interiorly of said locking member, pressure-movable closure means for the cylinder in contact with the cover and resilient means to urge said cover tightly over said opening, a pump rod extending through said member, and locking means on said member for securing the outer end of said pump rod when not in use.

6. In a spray tank closed-at one end and having an opening in the other end, a retaining ring around said Opening, a cover for said opening, a pump cylinder carried by said cover to extend into said tank, a cover locking member enga-geable with said ring, resilient means carried interiorly of said locking member to urge said cover tightly over said opening, a pressure-movable cap member disposed between said resilient means and said cover in contact therewith to function as a closure for said cylinder and transfer the spring pressure to said cover, and a pump rod extending through both said members.

7. In a spray tank closed at one end and having an opening in the other end, a retaining ring around sai-i opening, a cover for said opening, a pump cylinder fixedly secured to said cover, a cover locking member in the form of a sleeve with projecting means to engage said ring, a sealing screw in said member having a reduced inner portion, a spring around said portion inside the sleeve, a pressure-movable closure surrounding said pump cylinder and engaging the spring and cover to transfer spring pressure to said cover, and a pump rod extending through said closure and sealing screw.

8. In a spray tank closed at one end and having an opening in the other end, a retaining ring around said opening, a cover for said opening, a pump cylinder carried by said cover, a cover locking member in the form of a sleeve with projecting means to engage said ring, a sealing screw in said member having a reduced inner portion, a spring around said portion inside the sleeve, a dome-shaped pressure-movable closure for said pump cylinder cngageable at its upper end with the spring and at its lower end with the cover to transfer spring pressure to said cover, and a pump rod extending through said closure and sealing screw, said sealing screw being adjustable to vary the pressure of said spring on said cover, and holding means on the outer end of said screw to temporarily lock the outer end of said pump rod when the pump is not in use.

References Cited in the file of this patent UNITED STATES PATENTS Friend June 1, 1954

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