US2563718A - Shielded container - Google Patents

Description

Aug. 7, 1951 J. F. GIFFORD SHIELDED CONTAINER 2 Sheets-Sheet 1 Filed April 13, 1949 INVENTOR. JOHN F G/FFORD BY WM/QWL 1951 J. F. GIFFORD 2,563,718

SHIELDED CONTAINER Filed April 13, 1949 2 Sheets-Sheet 2 (72? 6. INVENTOR. JOHN F G/FFOAD x4 TTORNEK Patented Aug. 7, 1951 it UNITED STATES PATENT 1 OFFICE SHIELDED CONTAINER John F. Gifford, Richland, Wash., assignor to the United States of America as represented by the United States Atpmic Energy Commission Application April 13, 1949, Serial No. 87,193

4 Claims. 1

This invention relates generally to containers and more particularly to a new and improved container for use in storing, handling and transporting of radioactive materials. As is generally known, the handling of such materials requires adequate shielding and unless an unduly heavy and cumbersome structure is to be expected, it is necessary to provide structure designed particularly for this special purpose. The mere adaptation of a structure designed for use in another field does not usually satisfy the exacting requirements met in the radioactive handling "field. In view of this situation, the transporter disclosed in my copending application Serial No. 51,581, filed September 28, 1948, now Patent No. 2,533,102, was developed for the specific purpose of providing a container for radioactive materials, and has been found to satisfy a long felt need. It has now been determined, however, that certain additional improvements to the structure disclosed therein are desirable. One object of the present invention, therefore, is to provide a new and improved container providing a simple and effective locking means for a series of container trays.

Another object is to provide an improved container wherein the opening movement of a tray thereof serves to provide a closing movement for adjacent trays.

Another object is to provide an improved container for radioactive materials resulting in a large carrying capacity for a given amount of shielding.

A further object is to provide an improved container wherein the trays are slightly moved from locked position upon movement of the unlocking means for expediting subsequent withdrawal of any selected tray.

Still another object is to provide an improved container for radioactive materials maintained in separated compartments and in the use of which the operator is subjected to a minimum of radiation.

Other objects and advantages will become apparent from the following description and drawings in which massive bottom and top plates I0 and III of circular form and consisting of a radioactivity shielding material such as lead. A spacer rod I2 threaded into lower plate I l and securely aflixed in any suitable manner to upper plate ID may be disposed adjacent the periphery of the plates while diametrically across said plates a rotatable locking rod assembly having an axis portion 13 Figure 1 is a perspective view of the container and a cam surface portion 14 may be pivotally mounted therein adjacent the periphery of the same. The cam surface portion I l serves a purpose later to be described, while the axis portion [3 may terminate at one end in a lower pin section l5, which is adapted to turn in a suitable bearing aperture in the lower plate, and at the other end in an upper pin section 16, which likewise is adapted to turn in a similar bearing aperture in the upper plate. Suitable means for turning the locking rod assembly may include a lever l1 united to upper pin section It to serve as a crank and retained thereon as by means of a nut l8. Moreover, for ease in transporting the structure a conventional handle I9 may be provided.

A series of flat tray members 20 of generally circular form, as best shown in Fig. 3, are pivotally mounted adjacent their peripheries upon spacer rod 12 in a vertically overlapping relation. Each tray is adapted to swing horizontally about its pivot point with its flat upper surface in frictional engagement with the lower surface of an adjacent tray or plate and with its flat lower surface in frictional engagement with the upper surface of an adjacent tray or plate. D iametrically opposite its pivot point the periphery of each tray is indented with a suitable notch having nonsymmetrical sides and adapted to engage with the locking rod assembly in a manner later to be described. For the purpose of holding the radioactive material, or any other material is desired, each tray 20 is provided near its center with a space or depression 2] into which a circular dish, such as indicated at 22, containing the radioactive material may be removably positioned. As in my aforementioned copending application a lateral space or depression 23 joining the space 2| may be provided for ease in inserting or removing close fitting dishes by means of an appropriate tool.

In order to provide a substantially uniform shielding effect at all points on the exterior of the structure the diameter of space 2| in the trays is so chosen that the minimum distance from the periphery of space 2| on the topmost or lowermost tray to the periphery of the tray is about the same as the distance from such space to the exterior of the corresponding top or bottom plates l0 and II.

Referring now to Fig. 3 it will be noted that the notch on the tray 20 comprises a relatively long wall 30 extending into a generally semicircular dewith a greater radiusof curvature than the ra dius of the disk thus providing a greater distance from pivot point on rod 12 to the periphery of the tray on one side of the notch than to the periphery on the other side of the same." In mounting the several trays 28,. alternate trays are preferably provided with the, long wall 300i their notches alternately disposed with respect to the depression 3i whereby alternate trays when mounted upon the spacer rod may be swung or withdrawn horizontally in alternate directions.

Referring now to Fig. 4; a single tray pivotedon spacer I2 is diagrammatically shown in locked position in cooperation with the locking rod assembly, As will be noted, the cam surface 14 .of said rod at this time fully engages the depression 3| and is tangent tothe long wall 3i) of.

the notch while the peripheral edge 32 on the opposite side of the notch, if projected, would.

passthrough'thev cam surface closely adjacent to the axis I3 of the rod assembly. At this time. this. particular plate, as well as all other plates engaging the locking rod assembly, are in fully locked position and the entire structure may safely be. transported or stored.

lnlorder to. unlock the structure, the rod as-.

semblymay be turned in either direction. Assumingthat it is turnedcounterclockwise as indicatedinFig; 5, contact of cam surface l4 with long wall-3L moves the tray through a small angle-ra; Further movement of the ,rod assembly leaves the tray 2!] displaced at the same angle a, but moves. the cam section 14 to a withdrau'rn positionwith respect to this particular tray and all.

othershaving similarly disposed. walls 38. As a result, edge 32 will clear both the cam surface ll-zandtheaxis is of the locking rod assembly when the tray 20 is thereafter moved clockwise about pivot. l2 .to fully open position. On the other, hand, all trays having their walls 39 oppositely disposed to that of the. tray so illustrated tional safety, factor. Inlocking the trays, for

transportation or storage,-each tray is first positioned with its wall 30 in; contact with cam surface It whereupon by turning the locking rod on itsaxisl3' the surface It moves into a position filling. depression3l oneach tray and pulling the trays into the single axial position shown in Fig. 4.. Obviously, if for some reason it isv desiredto lock certain trays while leaving others unlocked thismay be-done without departing from the invention.

It hasalso been. found that in the handling of.

radioactive materials the user of this. structure may avoid unnecessary radiation exposure by loading, the, containerwhile. using the container itselfrfo'r. a shield, by withdrawing any given tray only .far. enough to permit insertion or removal of the dish 22, as shown for example by the position, ofthe righthandmost tray inFig. 3, andby having no more than one tray in fully withdrawn position at any one time. Other advantages will also, be, evident, to those skilled. in. the .art. Accordingly, the invention is; not intended to be restricted in its scope to the form as shown and described, but on the contrary should be restricted only as defined in the following claims.

Whatis claimed is:

l. Acontainer comprising a top plate, a bottom plate, a spacer between said plates, a plurality of fiat-surfaced, receptacle-containing trays com bined into a single stack by being vertically mounted between said plates and pivotally secured upon said spacer adjacent the periphery of the tray, each of said trays frictionally engaging with adjacenttrays ,and the uppermost tray and lowermost tray having frictionalengagement with said top plate and bottom plate, respectively, 'a notchin theperiphery of each tray substantially diametrically oppQsite' the mounting point of, said'tray, a space in said, trays for a radioactive material and disposed interiorly thereof at a distance from the nearest periphcry ofthe trays substantially equal to the thickness of said top plate, andadjustable retaining means cooperating withsaid matches and mounted in said plates andadapted in oneposition ,to lock said trays in fixed relation providing a closed container. and ina secondposition to permit rotation of said trays about. saidspacer in orderv to provide access to the receptaclehof each-tray.

2. ,Apparatusiaccordingto claim 1, wherein the notch in each tray has one side wall longer, than the other side wall.

.3. Apparatus according to. claim 11, wherein the notch in each tray has one side wall longer than the other side wall and at least, a plurality of said trays are mounted with adjacent long away to provide peripherally extending marginal walls, aspace in said tray for a radioactive ma? terial and disposed interiorly thereof at. a,.dis;- tance fromthe nearest periphery ofthe trays substantially equal to. theuthicknessrof said. top. plate, andadjustable retaining. means cooperate, ingwwithsaidnotchesv and mounted in said plates,- and adapted in one position to lock said trays in. fixed relation providing a closed container; and movable. toa position of alignment with they cut.

away portions of said notches to permit rotation.

of. said trays about saidspacer in order to provide access to the receptacle of each tray.

' JOHN F. GIFFORD.

' REFERENCES CITED.

The following references are of record .in the, file of" this patent UNITED STATES PATENTS Number Name Date 982,767 Dunham 4--- Jan. 24, 1911 1,504,967 Orendorff'r Aug. 12, 1924' 1,831,401

Weidlich et a1 NOV. 10,1931

Images