Mechanical lock for vessels

A segmented mechanical lock for a container including arcuate segments 12, 14, 16 having upstanding pins 18, pivot ring 20 having tangential slots 22 overlies the segments and upon rotary motion moves them outwardly into a groove 48 locking lid 6 in position in vessel 4.

TECHNICAL FIELD 
This invention relates to a mechanically locked, plug-type cover for 
permanently sealing waste containers when used in conjunction with a 
chemical seal and more particularly to the mechanism for effecting the 
mechanical lock and the method of sealing said container. 
BACKGROUND ART 
A conventional method of disposing of waste material, which is toxic, 
radioactive, or otherwise harmful is to place said material in an 
impervious container seal it and bury it at a remote location. 
Fiberglass reinforced plastic tanks have been found to be satisfactory for 
certain radioactive material as well as other toxic material. However, 
because of the difficulty in achieving a seal around the filling opening 
which would withstand the required stress and drop tests, the openings 
have necessarily been small. 
Whereas the restricted opening size has not proven to be a great detriment 
in many applications, there has been expressed a desire to have an opening 
which is larger in size for accepting a greater variety of materials as 
well as allowing a more rapid filling of the container. 
DISCLOSURE OF THE INVENTION 
With the above noted prior art and problems in mind, it is an object of the 
present invention to provide a storage container having a mechanically 
locked and chemically sealed cover of a non-corrosive chemically resistant 
material. 
It is yet another object of the present invention to provide a method of 
mechanically and chemically sealing a fiberglass reinforced plastic 
vessel. 
A further object of the present invention is to provide a vessel and seal 
of sufficient integrity such that the vessel adequately contains the 
material to be disposed of by withstanding the pressure of burial at a 
specified depth. 
Yet another object of the present invention is to provide a mechanical 
locking mechanism which is simple of structure, of a nondegrading material 
and yet reliable and simple to operate. 
Still a further object of the present invention is to provide a mechanical 
lock for a vessel wherein the locking mechanism extends about the majority 
of the periphery of the cap to be sealed distributing any stress thereon 
around substantially the entire periphery.

BEST MODE FOR CARRYING OUT THE INVENTION 
As seen in FIG. 1, the neck 2 of the waste holding container 4 is shown 
with the plug cap 6, having an upwardly projecting dome 8, in place. It is 
to be understood that the cap could be of various shapes and the 
configuration is not critical. As seen in the exploded view is the 
segmented locking ring 10 having, in the preferred embodiment, three 
segments 12, 14, 16 each of which has a pair of upstanding pins 18. Pins 
18 cooperatively interact with pivot ring 20 having a plurality of slots 
22 each designed to mate with a respective pin 18. Each of the slots is 
tangential to a circle intermediate the inner edge 24 and outer edge 26 of 
pivot ring 20 and extend in the same direction. When pivot ring 20 is 
placed in position over pins 18 with inner edge 24 surrounding dome 8 of 
plug 6 and rotated by cover plate 30 described hereinafter in the 
appropriate direction segments 12, 14 and 16 move outwardly. A pair of 
pins 28 project upwardly from pivot ring 20 to interact with a spanner 
wrench or other appropriate tool at the time of locking the lid, i.e. 
expanding the locking ring. 
Cover plate 30 is provided with a central dome 32 which is closely 
configured to ride on dome 8 of the cover 6 and a plurality of inwardly 
directed scalloped-type cuts 34 to accommodate upwardly extending pins 28 
and any extension of pins 18 beyond the upper surface of pivot ring 20. 
Referring now to FIG. 2, the relationship between the container 4 and the 
cover may more easily be seen. As seen in this view, the main body of the 
container 4 is a fiberglass reinforced plastic shell 40 which may be 
covered with a shock absorbing bumper material 42. The fiberglass 
reinforced plastic shell 40 includes an inwardly extending lip 44 upon 
which the lid 6 is seated. A seal can be affected between 44 and the 
outwardly extending congrous lip 46 of the lid by either an O-ring gasket 
assembly or alternatively a elastomer bead placed upon the lid prior to 
the locating of the lid itself. An annular groove 48 accommodates the 
locking ring segments 12, 14 and 16 and an upwardly extending edge 50 
accommodates the sealing resin as explained hereinafter. 
As seen in FIG. 2, the locking ring segment 16 along with segments 12 and 
14 are in their initial unlocked position; and as seen in FIG. 3, they 
have been moved outwardly to their locking position, in the groove 48, 
mechanically locking the lid 6 to the tank 4. 
In operation, when it is desired to seal the first embodiment tank, an 
elastomer bead is placed about the lower lip of the lid 6 and it is placed 
within the tank sealing the lid to the tank to prevent sealant from 
entering the tank during the succeeding steps. As an alternate, as stated 
above, an O-ring gasket could be placed to perform the same function. 
Following the placement of the lid on the ledge in the tank a sealant is 
poured along the edges of the lid sealing all of the openings and 
providing a lubricant for the locking ring segments 12, 14 and 16. Once 
the sealant is in position, cover plate 30 is rotated, forcing locking 
rings 12, 14 and 16 to expand outwardly to that position as shown in FIG. 
3. Following the movement of the locking ring segments outwardly the 
entire upper portion of the tank top up to the top of ledge 50 is filled 
with a filled resin sealant, and adhesive which gives the lid additional 
strength and improves the seal. 
Reference is now had to FIG. 4 where the vessel 60 having an upwardly 
facing opening 62 is shown. It is to be noted that the inner portion of 
the opening or neck 62 includes a lowermost inwardly projecting ledge 64 
having a relatively flat upward face 66. Spaced slightly above the flat 
face 66 is a radially outwardly extending groove 68 to receive the 
mechanical locking mechanism as described hereinafter. The plug or cap 
generally designated as 70 includes a flat circumferential outer surface 
(seen best in FIGS. 5 and 6) of a diameter such that it will rest upon the 
flat surface 66 when in position. Lid 70 also includes a flat 
circumferential upper surface 72 which surrounds an upwardly extending 
cylindrical surface 74 for purposes to be hereinafter described. Upon the 
upper surface of upwardly extending cylindrical element 74 are a plurality 
of openings 76 which are threaded to receive fastening member 78 securing 
flat disk 80 in a position overlapping but spaced from surface 72. The 
remainder of the main body portion of the plug member 70 includes a 
generally flat upper surface 82 having secured thereto a handle or lifting 
member 84. 
Flat disk 80 has secured to the lower portion thereof intermediate its 
inner and outer radius, a downwardly extending cylindrical member 86 and a 
plurality of radially extending threaded openings 88 adapted to receive 
threaded fastening members 90 which in conjunction with washers 92 secure 
leaf springs 94 in position. There are six springs 94 distributed about 
the circumference of cylinder member 86. 
Six arcuate members 96 having a chamfered lower surface 98 are located 
resting upon flat surface 72, each of which compreses a spring 94 and are 
held in position in the unlocked position by pin member 100. 
Referring now to FIG. 5 the plug type closure can be seen in the unlocked 
position i.e. pin 100 has not been removed and the elements are denoted by 
the same numerals as in FIG. 4 for clarity. 
As seen in FIG. 5, the plug-like cover is in place in preparation for 
sealing. It is to be noted that there is a gasket 102 sealing the space 
between the lid and the container itself. 
As seen in FIG. 6, the plug lid is sealed. The sealing is accomplished 
through the process of first adding a liquid, combination 
sealant/lubricant, 104 pulling pins 100, allowing spring 94 to expand 
forcing the locking element 96 outwardly into the groove 68. The sealant 
lubricant is allowed to cure thus sealing the entire space. A second resin 
106 is then added as a protective cover for the entire sealed vessel. 
Thus as can be seen the present invention contemplates the utilization of a 
simple mechanical structure backed by a chemical seal to provide a plug 
type sealed container for harmful chemicals or the like. 
Thus as can be seen the present invention teaches the concept of a sealed 
cover for waste material wherein the integrity of the tank is not 
compromised. The sealed mechanical link between the tank and the cover 
results in an integral tank/cover unit.