Patent Number: 055330894
Section: description

DETAILED DESCRIPTION OF THE INVENTION Reference is now directed to the accompanying drawing, wherein there is shown in FIG. 1 apparatus disclosing the invention and illustrating its mode of use. An instrument, indicated generally by the numeral 1, embodies the invention. It comprises a rack 2 and a unit 3 supported by the rack. The function of the rack is to support and position the unit between an x-ray emitting device or source 4 and the body 5 of a patient. The function of the unit is to collimate and limit rays 6 issuing from the source to a particular area of the body, and also to shield from the rays areas of the body surrounding the particular area. A photographic film 7 is disposed below a conventional table 8 supporting the body to obtain a representation of the x-rayed area of the body. As a means for supporting the unit relative to the source of x-rays and the body of the patient, the rack 2 may, accordingly, take various forms for such purpose. Here, a practical form of the rack for such purpose is illustrated. The rack 2 has a rear element 9 mounted for swivel movement relative to a support 10. A strut 11, pivoted at its rear end 12 to the element 9, is pivoted at its opposite end 13 to a second strut 14. The latter is pivoted at its forward end 15 to a universal joint 16, which in turn is swiveled upon a short rod 17 extending from a side 18 of a frame member 19 of the unit 3. Key elements defined by the pivots at the various joints of the rack are manipulative to make secure adjusted positions of the related components of the rack to one another. The rack is manually adjustable and extendible to position and support the unit 3 between the source 4 of x-rays and the body 5 of the patient. The frame member 19 of the unit 3 is multi-sided, preferably rectangular in configuration; and it is formed of cylindrical rod of aluminum or other lightweight material. The frame defines a continuous perimeter about an aperture 20, which aperture serves for passage of x-rays from the source 4 to a body 5 located beneath the unit. Depending from each of the sides 18 of the frame 19 of the unit 3 are separate panels 21 of flexible radio-opaque material, such as is provided by lead sheeting, or lead impregnated vinyl. Each panel is pivotally supported by a hinge 22 to the related side of the frame. The several panels may, accordingly, be selectively pivoted to one another about the frame to vary the size opening of the aperture at its bottom end. The panels are preferably rectangular in form and serve, when adjustably pivoted relative to one another, to define and limit as needed the dimension of the bottom or outlet end of the aperture 20, whereby x-rays issuing from the source 4 through the aperture are concentrated, limited and collimated as desired to impinge upon a particular area of the body of a patient underlying the aperture of the unit 3. Impingement of any of the rays upon a panel defining the aperture is absorbed by the radio-opaque material of the panel and, accordingly, is shuttered from contact with surrounding areas of the body of the patient; and only that portion of the rays intended to impinge upon the body of the patient passes through the aperture of the unit. In effect, as the panels about the frame of the unit are selectively pivoted to adjusted positions relative to one another, the direction of x-rays issuing from the source through the aperture of the unit to the body of a patient may be collimated, limited and beneficially controlled. The flexible nature of the panels enables portions of the panels which may be in contact with the body of the underlying patient to be flexed about the body. The several panels of the unit are provided with translucent perforations 24 along their lower ends. X-rays which may pass through these perforations and register upon the film 7 below the patient provide a scale indication of the size of the exit end of the aperture from which the rays project to the body of the patient. The several hinges 22 supporting the panels to the frame 19 of the unit 3 have a friction engagement with the frame, whereby they are held in their pivoted positions about the frame until the panels are re-pivoted to other positions. In FIG. 4 is shown a modified form of a hinge 25 which may be employed in supporting a panel to the frame of the unit. This hinge is in the form of a band which sleeves a ring of closely spaced holes 26 formed in the related tubing of the frame. A ball detent 27 disposed in a hole of the hinge is adapted under the load of a leaf spring 28 mounted to the hinge to engage in part in one of the holes 26 of the frame accordingly as the panel is pivoted about the frame, whereby the pivoted position of the related panel is adapted to be secured. And, it is apparent that as the panel is manually pivoted, its pivoted position and detent engagement about the frame may be readjusted, and the dimension of the aperture for passage of x-rays from the source to the body of the patient may be varied. While an embodiment of the invention has been illustrated and described in detail, it is to be expressly understood that the invention is not limited thereto. Various changes of form, design and arrangement may be made in its components without departing from the spirit and scope of the invention as the same will now be understood by those skilled in the art; and it is my intent, therefore, to claim the invention not only as shown and described, but also in all such forms and modifications thereof as may be reasonably construed to fall within the spirit of the invention and the scope of the appended claims.