BACKGROUND OF THE-INVENTION
This invention relates to film holding apparatus and 5 more particularly to cassettes for holding radiographic film.
There has been developed a film cassette for x-ray or other radiographic film which is of unique, light-tight construction and is extremely simple to use. Represen- 10 tative cassettes of this type are disclosed in Harry S. Wolf U.S. Pat. No. 2,213,437 granted Sept. 3, 1940. Such cassettes customarily include a front panel and a back panel having a felt cushion. The film is positioned between intensifying screens located intermediate the 15 two panels. The cassettes commonly are stored within the screens and film in place on shelves in radiographic rooms or other locations with only the edges of the cassettes visible. When a picture is to be taken, an 2Q orderly or technician selects the cassette with the appropriate screen and film combination, and the picture is made.
Heretofore, difficulties have been encountered in the construction and handling of film cassettes and similar 25 film holding apparatus. Of particular importance is the need for rapidly and accurately identifying a given cassette and distinguishing it from the comparatively large number of adjacent cassettes at the storage location. In the making of an x-ray picture, for example, 30 one of the more significant parameters is the speed of the screens within the cassette, and it is important to determine the screen speed quickly and without excessive handling. Also, information often is needed concerning the particular department or radiographic 35 room in which the cassette has been stored, the type of cassette, e.g. photo-timing, grid cassette, etc., or other factors necessary or desirable to determine selected parameters consistent with the purpose for which the cassette is employed. Prior cassettes have proved defi- 40 cient in these respects, with the result that in several instances the cassettes have been incorrectly identified and a substantial amount of time was wasted before the proper cassette could be located.
One general object of this invention, therefore, is to provide a new and improved cassette or similar apparatus for holding radiographic film.
Another object of this invention is to provide such 50 apparatus which may be readily identified merely by observing any one of the edges of the cassette.
A further object of the invention is to provide apparatus of the character indicated which is economical to manufacture and thoroughly reliable in operation. 55
In one illustrated embodiment of the invention, the apparatus includes a rectangular front panel for supporting radiographic film and a removable back panel overlying the film and having a planar surface in facing relationship therewith. The planar surface of the back 60 panel is faced with lead and includes a layer of felted fibrous material between the lead and the film. The back panel is held in place by a pair of leaf springs which are supported for pivotal movement about axes intermediate the ends of the springs. The assembly of 65 panels is surrounded by a rectangular frame member having four edge portions which meet at the four corners of the frame.
In accordance with one feature of the invention, the cassette includes an indentation which is arranged for the receipt of identifying indicia and is uniquely located on the cassette so that the indicia is readily accessible to the observer.
In accordance with another feature of the invention, in certain important embodiments, a plurality of indicia carrying indentations are provided at selected locations along the edge portions of the cassette. The arrangement is such that a hospital orderly or technician may readily select a particular cassette from the large number of cassettes commonly located in the cassette storage area.
In accordance with a further feature of several advantageous embodiments of the invention, each identifying indicia is mounted entirely within its identation. With this arrangement, the indicia cannot become caught on clothing, etc., during handling.
In accordance with a still further feature of the invention, in some arrangements, the indicia is arranged in accordance with Braille or other preselected code. As a result, a large number of screen speeds, cassette types, etc. may be readily identified in a rapid and straightforward manner.
The present invention, as well as further objects and features thereof, will be understood more clearly and fully from the following description of certain preferred embodiments, when read with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a cassette for holding x-ray film in accordance with one illustrative embodiment of the invention.
FIG. 2 is a plan view of the back of the cassette.
FIG. 3 is a sectional view taken along the line 3—3 in FIG. 2.
FIG. 4 is an enlarged elevational view of a corner of the cassette, with certain portions shown broken away and in section.
FIG. 5 is an enlarged fragmentary sectional view similar to a portion of FIG. 3 but with certain parts omitted for purposes of clarity.
FIG. 6 is a perspective view of an identifying disk for the cassette.
FIG. 7 is a fragmentary perspective view of one corner of a cassette in accordance with another illustrative embodiment of the invention.
FIG. 8 is an enlarged fragmentary sectional view taken along the line 8—8 in FIG. 7.
DESCRIPTION OF CERTAIN PREFERRED
Referring to FIG. 1 and 2 of the drawings, there is shown a cassette for x-ray film which includes a rectangular cover panel 10. The panel 10 is provided with the usual D-shaped ring 11 for opening and closing the cassette and with two hinges 12 and 13 along the edge of the panel opposite that adjacent the ring 11. Two leaf springs 15 and 16 are pivotally supported on the panel 10 intermediate their ends for movement between the full line position shown in FIG. 2 and the dotted line position. These springs serve to hold the panel in place when the cassette is closed.
The hinges 12 and 13 are connected to one side of a hollow rectangular frame 20. As best shown in FIGS. 4 and 5, the frame 20 is of rectangular cross section, and each of the four sides of the frame is formed from a