US2881944A

US2881944A - Heat actuated closure for containers

Info

Publication number: US2881944A
Application number: US637050A
Authority: US
Inventors: Ernest L Johnson
Original assignee: Individual
Current assignee: Individual
Priority date: 1957-01-29
Filing date: 1957-01-29
Publication date: 1959-04-14
Anticipated expiration: 1976-04-14

Description

E. JOHNSON 2,881,944

April 14, 1959 HEAT ACTUATED CLOSURE FOR CONTAINERS 4 Sheets-Sheet 1 Filed Jan. 29, 1957 April 14, 1959 E. JOHNSON 2,

HEAT ACTUATED CLOSURE FOR CONTAINERS Filed Jan. 29, 1957 v v 4 Sheets-Sheet 2 April 14, 1959 E. L. JOHNSON HEAT ACTUATED CLOSURE FOR CONTAINERS 4 Sheets-Sheet 3 Filed Jan. 29, 1957 3 3 v 3 Na wN vN MN on 7 April 14, 1959 E; L. JOHNSON 2,881,944

HEAT ACTUATED CLOSURE FOR CONTAINERS Filed Jan. 29, 1957 4 Sheets-Sheet 4 INVENTOR. [CA 57 A. J #17504 a,as1,944

' HEAT ACTUATED LOSURE FOR CONTAINERS :Ernest L. Johnson, Sacramento, Calih, assignor to the United S ates of America as represented by the Secretary of the Force Application January 29, 1957,:Serial No. 637,050 v1 Claim. c1. 220-88) (Granted :under Title 35, 13. S. Code (1952), see. 266') The invention described herein may be manufactured and used by or for the United States Government for governmental purposes without payment to me of any royalty thereon.

This invention relates to a storage bin, and more particularly, to a heat actuated closure device for a storage a bin adfipted'to hold inflammable or explosive material.

Thermal or heat actuated closure devices for storage bins are well known, and have functioned well for safeguarding certain kinds of inflammable material. They have been less satisfactory where the storage bin was used to store sensitive high explosive materials, because they did not exercise any control over the rate at which the bin was sealed when the thermal device was actuated. If the container closure was a heavy cover, the shock produced by the cover slamming shut over the storage bin could cause an explosion in the material inside the container.

Accordingly, the principal object of this device is to provide a heat actuated closure device for a storage bin provided with means for controlling the force of engagement between the storage bin and its cover.

An additional object of this invention is to provide a storage bin for the storage of combustible or explosive materials having a counterweighted heat actuated cover.

Still another object of this invention is to provide a heat actuated closure device for a storage bin provided with means for controlling the speed at which the storage bin is closed.

Yet another object of this invention is to provide a storage bin for the storage of explosive and combustible materials which is simple to manufacture, economical and safe.

These and further objects of this invention will become more apparent when read in the light of the accompanying specification and drawings wherein:

Figure 1 is a front perspective view of the storage bin with the cover closed.

Figure 2 is a front perspective view of the storage bin with the cover open.

Figure 3 is a rear perspective view of the storage bin with the cover closed.

Figure 4 is a side view of the storage bin with the cover closed.

Referring now to Figure 1 of the drawing, a storage bin indicated generally at comprises a container 12 and a cover 14. The cover is pivotally secured to the container by hinges or pivots 16. A back stop 18 for cover 14 is rigidly mounted on the container 12. As best seen .in Figures 2 and 4 with the cover 14 opened to its widest extent so that it engages back stop 18, the center of gravity of the cover is such that if left to itself, it would fall back into its closed container sealing position. To prevent this from happening, counterweights 20 and 22, see Figure 3, are connected to the cover. These counterweights apply forces to the cover which oppose the biasing force exerted by gravity. A pair of guide tubes 24 and 26 are rigidly secured to the rear surface of the container,

2,881,944 Patented Apr. 14, 1959 and counterweights 20 and 22 ride in these tubes. These guide tubes have several functions. They .control the direction of the forces applied by the counterweights to the cover, and protect and isolate the counterweights from each other .and from outside forces.

A vertical upstanding :support 281s rigidly connected to the container 12 and a shaft 30 is rotatably mounted in the upper end of this support. A pair of

pulleys

32 and 34 .are rigidly secured to this shaft in spacedpar'auel 0 lationship. An additional pulley 42 and a fixed support t or bracket 40 are connected to cover .14 for purposes to be described below.

A cable or string .38 is connected at one end to counterweight 20. It then passes .over pulley 34, and vis fixedly secured at the opposite end to the cover 14 at bracket 40. Similarly, a cable or string 36.is connectedat'one end to counterweight 22. It then passes over pulley 32 and also over pulley 42 which is rotatably mounted "in cover 14, and moves along the interior surface of cover 14 Where it terminates at the fusible link portion 44. This fusible link 44 is secured to the container 12 by means of a bracket 46, see Figures 2 and 4. The magnitudes of counterweights 20 and 22 are jointly suflicient to hold cover 14 in open position against back stop 18, but each individual counterweight is not suificient to do so.

The operation of this closure is as follows: In the event the material stored in the container becomes ignited or the temperature in the room exceeds any predetermined amount, the fusible link 44 will melt disconnecting counterweight 22 from cover 14. If this happens while the container is in an open position, the force of gravity exerted on the cover will be greater than the opposing force exerted by the remaining counterweight 20, causing the container cover 14 to close. The speed or rate of closure of the container cover can be regulated by controlling the size of the remaining counterweight 20. In the event a container is storing some high explosive material such as nitroglycerine, the speed at which the cover closes can be made as slow as desired to reduce the force of engagement between the cover 14 and the container 12.

These counterweights also have an added utility. When the container is large and the cover is heavy, they provide a means for easily opening the container. It is apparent, for example, that weights 20 and 22 and the height of support 28, can be so chosen that the cover is in a state of complete equilibrium when the cover is in a position parallel to the ground. Simple physical considerations show that such an equilibrium position is unstable and that the slightest pressure on the cover exerted in an upward direction will cause the cover to open until it engages back stop 18, and the slightest pressure on the cover in a downward direction will cause the cover to slowly close. In addition to the ease in opening the container provided by this arrangement, an additional safety feature is apparent. When the container is large and the cover is very heavy, this structure prevents the cover from slamming down into closing position and possibly injuring the hands or arms of persons extracting material from the container at that moment.

It is apparent that many modifications can be made WlIhOllta departing from the spirit of the invention and accordingly, the above disclosure should be considered as illustrative and not restrictive. The scope of the above invention should be determined by reference to the appended claims wherein:

I claim:

In a storage bin for the storage of combustible and explosive material, a container for housing combustible and explosive material, a cover hingedly mounted on said container normally biased towards the closed position under action of gravity and having an opening incorporated therein adjacent the forward edge thereof, an upstanding support rigidly attached to the rear surface of said container and extending upwardly to a substantial overhanging portion relative to the top of said container, a pair of spaced, parallel pulleys rotatably afiixed to and spaced from said bracket and adjacent said opening, a

fusible link adaptable for separation at a predetermined temperature mounted on the lower surface of said cover adjacent the rear edge thereof, a first cable aflixed at one end" to said bracket on the upper surface of said coverand threaded over one of said spaced, parallel pulleys positioned adjacent the upper surface of said upstanding support and terminating at its other end in one of said tubular guides, a second cable attached at one end to said fusible link on the lower surface of and adjacent the rear edge of said cover and having one section threaded through said opening incorporated adjacent the forward edge of said cover, a second section threaded over the pulley mounted on the upper surface of said cover adjacent said opening, and a third section extending from said last-named' pulley to the other of said spaced, parallel pulleys positioned adjacent the upper surface of said upstanding support and terminating at its other end in the other of said tubular guides, and a pair of counterweights within said tubular guides'and attached to the respective ends of said first and second cables terminating in said tubular guides and cooperating with each other to overbalance the normal biasing force of said cover and normally retaining said cover in open, raised position, saidbiasing force being in excess of the counterforce of the counterweight attached to said second cable a predetermined minimum amount to gradually move said carrier to its closed position on destruction of said fusible link to release the cooperating counterweight attached to said first cable.

References Cited the file of this patent UNITED STATES PATENTS 1,213,686 Owens Ian. 23, 1917 1,683,571 Mueller Sept. 4, 1928 2,535,368 Norcross Dec. 29, 1950 2,679,949 Clinton June 1, 1954