Abstract:
A child positioning apparatus for X-ray photography having improved adjustment mechanisms. In particular the positioning of the X-ray film cassette has been improved by using a friction fastner. The friction fastner passes through a groove in the vertical portion of a L-bracket and attaches to a tray for holding the X-ray film. The position of the tray is adjusted by loosening the friction fastener, positioning the tray and then re-tightening to fix the X-ray film cassette into place.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a child positioning apparatus for X-ray photography or imaging and more particularly to a child positioning apparatus for X-ray photography with adjustable dial lock features an improved upright latch and adjustment. 
     BACKGROUND OF THE INVENTION 
     An X-ray positioner for an upright child is first described in U.S. Pat. No. 3,051,832 (&#39;832) issued to Jalmer Pigg, Sr. on Aug. 28, 1962, the contents of which are incorporated herein by reference. While the device described in the &#39;832 patent was effective in the upright positioning of a child being X-rayed, there were several shortcomings in its operation. 
     A significant problem with the &#39;832 invention was the complex method used to adjust the position of the X-ray film cassette relevant to the position of the patient. As best seen in FIG. 1, the &#39;832 film positioner  100  principally comprised film carriage  104  which included hooks  101  with the X-ray cassette  103  resting on the hooks  101 . Film positioner  100  had rear side tracks (not shown) which extended to the rear of the L-angle  108 . Latch  105  in the &#39;832 patent was employed to secure carriage  104  in position after having been adjusted upward or downward by an X-ray technician. In tightening the latch  105 , the hard surface of the latch  105  was tightened against the hard surface of the rear tracks  106  of the carriage  104 . To create adequate friction between the two hard surfaces the latch  105  was often over-tightened, placing great stress on mounting pin  109  and resulting in frequent breakage. A similar mechanism was used on the shield and indicia device located on the front of the child positioner, also shown in FIG. 1 as  110 . 
     A subsequent patent, U.S. Pat. No. 5,600,702 (&#39;702) attempted to resolve these latching issues by adding pads at the end of the latch to increase friction between the latch and the film holder. As best seen in FIG. 2, friction pads  107  were added to the end of the latch against the sidetracks of the carriage  104  to attempt to obviate the necessity of over-tightening the latch. Similarly, friction pads  107  were added to latch  111  that secures indicia plate  112  into position. While the problem of ineffective latching is mitigated by this improvement, the process remains unwieldy and generally requires the use of two hands to adjust the position of the X-ray film cassette. One hand is used to hold the cassette carriage while another hand operates the latching mechanism. 
     A second problem not addressed by either U.S. Pat. No. 3,051,832 or U.S. Pat. No. 5,600,702 is the difficulty associated with placing the child in the positioner while adjusting the left and right upright restraints in place around the child. Formerly, the uprights were secured to the carousel by sliding a wedge attached to the upright by an L-bracket, into a slide block by passing the wedge over a pop-up button. The upright would then be held in place as the pop-up button released, blocking passage of the wedge out of the slide block. Over time, these pop-up buttons have tended to become increasingly less responsive, permitting the wedges to slide out of the slide blocks at inopportune times. The pop-up button fastener is particularly problematic when, over time, the pop-up button wears a groove on the bottom of the slide block. In this instance the pop-up button begins to rest at the bottom of the wear-groove and the wedge is able to slide out of the channel unimpeded. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the invention to provide an upright child positioning apparatus for X-ray photography with improved adjustment mechanisms. 
     It is a further object of the invention to provide a child positioning apparatus with improved placement and locking of the left and right upright restraint members. 
     The present invention provides for these and other objectives with at least three material advantages over the prior art. First, the invention uses an X-ray film cassette positioning system that can be operated by using a single hand. The film cassette is restrained in position by two friction fasteners such as dial knobs. One dial knob restrains the film cassette vertically and a second dial knob restrains the cassette horizontally. Second, a similar positioning system is used to hold the position of the shield and indicia plate. A single dial knob maybe used to hold the position of the shield on which the various indicia markers are placed. Third, the upright restraints are more securely held in place with improved fasteners at the ends of the channels of the slide block and an improved strap assembly. In addition, a new turntable locking mechanism has been devised. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side plan view of the positioner according to the prior art. 
     FIG. 2 is a side view of the positoner according to the prior art including the friction pads, where the dotted line shows the position that would be occupied by the body of a small child supported in the positioner. 
     FIG. 3 is a perspective view of the present invention. 
     FIG. 4 is a perspective view of the film cassette positoner of the present invention. 
     FIG. 5 a  is a top plan view of the slide block of the present invention. 
     FIG. 5 b  is a cut-away view of the slide block showing the spring mechanism. 
     FIG. 6 a  is a top view of the present invention with upright restraints removed. 
     FIG. 6 b  is a top view of the present invention with upright restraints engaged. 
     FIG. 7 is a side plan view of the upright restraints of this invention with strap portions engaged. 
     FIG. 8 is an exploded perspective view of the positioner for the indicia plate and shield. 
     FIG. 9 a  is a top view of the lock disengaged from the carousel. 
     FIG. 9 b  is a top view of the lock engaging the carousel. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention is designed to improve the positioning of a child during X-ray photography. Referring now to the drawings in more detail. FIG. 1 illustrates a prior art upright child positioner, which uses film positioner  100  with latch  105  to secure rear brackets of carriage  104  to L-angle  108  after the X-ray film cassette  103  is positioned properly for taking an X-ray. 
     FIG. 2 illustrates an improved prior art child positioner in that the latch  105  has friction pad  107  to facilitate securing the rear tracks of carriage  104  to the L-angle  108 . A similar friction pad  107  is used on the indicia latch  111 . 
     FIG. 3 illustrates the child positioner of this invention. The child positioner  10  is based on top  50  stabilized by frame  55 . The frame  55  is preferably made from stainless steel to prevent corrosion, and welded at its principal joints to prevent gradual wobbliness due to loose fasteners. Frame  55  also supports accessory tray  57  which can hold extra parts or accessories for the child positioner  10 . For instance, accessory tray  57  may hold an additional pair of upright restraints to accommodate larger or smaller children. Wheels  59  attached to the frame  55  facilitate movement of the child positioner. A turntable in the form of carousel  16  sets in the center of the top  50 . In a preferred embodiment, the carousel  16  and top  50  are made of polyethylene so that little friction exists when turning the carousel  16 . Ball bearings may be positioned between the top  50  and carousel  16  to facilitate rotation of the carousel  16  relative to the top  50 . In a more preferred embodiment the carousel  16  rests on ultra-high molecular weight polyethylene (UHMW-PE) pads attached to the top  50  for even greater friction reduction. Because the carousel  16  is capable of being rotated with little resistance a preferred embodiment of the child positioner  10  contains a locking mechanism such as slide-lock  91 . The slide lock  91  engages a selected lock hole  90  on the side of the carousel  16 , which prevents the child movements from changing the position of the carousel  16  relative to the X-ray film cassette  15 . 
     The carousel  16  holds right and left upright restraints  32 ,  30 , best seen in FIG. 7, in a removable fashion. An additional preferred feature of the present invention is upright restraint pads  44 , which serve to cushion the upright restraints  30 ,  32  on top of the carousel  16  and to provide additional friction to prevent the upright restraints  30 ,  32  from slipping when positioned around a patient. The upright restraints  30 ,  32  are pivotably secured to the carousel  16  by slide block  40 . Slide block  40 , shown in FIGS. 5 a  and  5   b,  uses spring loaded guides  42   a,    42   b  to hold wedges  38   a,    38   b  shown in FIG. 6 b,  in the slide block  40 . Another preferred feature of the present invention is wing clamp  34  which serves to fix the upright wing braces  31   a,    31   b  shown in FIG. 6 b,  to the carousel  16 . Clamps  34  are rotated over wing braces  31   a,    31   b,  thereby applying downward pressure and forcing the wing braces  31   a,    31   b  against the restraint pads  44 , which preferrably has a neoprene or other compressible synthetic surface. 
     The seat  49  is also supported by the carousel  16  and can be adjusted vertically to accomodate patients of varying height. The seat  49  is held in place by seat lock  52  which engages as a detent in one of a plurality of engagment contacts such as serations  33  of the seat stand  51 . The seat lock  52  can be retracted to adjust the height of the seat  49  by pulling the lock trigger  54  which sets atop seat lock block  56 . The locking mechanism also features lock cover  53  which guards against breaking the seat lock  52  when the seat  49  is inadvertantly adjusted without first pulling the lock trigger  54  to disengage the lock from the seat  49 . The seat lock cover  53  serves to prevent the application of leverage that could be applied by an engaged seat lock  52  being moved by corresponding movement of the seat stand  51 . 
     As shown in FIG. 3, the X-ray film cassette  15 , resting in tray  67 , is properly positioned relative to seat  49  by film positioner  60 . The film positioner  60  shown in detail in FIG. 4, is attached to the table  50  by mounting block  61 . FIG. 4 illustrates the cassette positioner  60  in isolation. The cassette block  61  is attached to the table  50  by wing bracket  64   b  and a second matching opposite wing bracket (not shown) positioned on opposing sides of the cassette block  61 . The horizontal portion of L-angle  62  is slidably positioned between cassette bracket guides  69   a  and  69   b.  A pass through friction fastener such as horizontal dial knob  65  may be loosened to permit movement of the L-angle  62  along horizontal groove  77 , indirectly moving the X-ray film cassette  15  laterally with respect to the patient. Movement is facilitated by constructing the top layer of the mounting block out of UHMW-PE, or similar materials, thereby reducing friction between the mounting block  61  and L-angle  62 , obviating the need for ball bearings in that position. Another pass through friction fastener such as vertical dial knob  66  is used in a similar manner to move the tray  67  vertically through tray guides  68   a  and  68   b  along the vertical portion of L-angle  62  through vertical groove  78 . The tray  67  is shown near its top position. The pass through fastener systems allows the X-ray technician to adjust the position of the x-ray film cassette  15  with a single hand. This is because a pass through fastener is activated (loosened or tightened) on the side of the adjusting carriage opposite tray  67 , yet passes through the vertical support to remain in communication with tray  67 . 
     FIG. 5 a  is a top view of the slide block  40  as attached to the carousel  16  by fasteners such as screws  43 . The slide block  40  contains a lengthwise channel  48  blocked by divider  41  creating channels  48   a  and  48   b  for receiving the upright restraint wedges  38   a  and  38   b  of the left and right restraints  30 ,  32  best seen in FIG. 6 b.  The wedge  38   a  is received into channel  48   a  by pulling spring loaded guide  42   a  to compress the spring  45  and remove slide  46   a  from the end of channel  48   a . Once the wedge  38   a  is positioned within channel  48   a  the spring-loaded guide may be released closing slide  46   a  and securing the left upright restraint  30 . The spring-loaded guide  42   a  can be easily opened by using the index finger, thereby removing the slide  46   a  from channel  48   a.    
     FIG. 5 b  is a cut-away view of the spring-loaded mechanism for the slide block  40 . Spring  45  is compressed when the spring-loaded guide  42  is drawn to remove slide  46  from the channel  48 . When the spring  45  is compressed the channel  48  is cleared for receiving the wedge  38  of the upright restraint  30 . As shown in FIG. 6 b,  when the spring  45  is released the slide  46  re-enters the channel  48  to block passage of the wedge  38  thereby securing one end of the upright restraint  30  into position. 
     FIG. 6 a  illustrates the child positioning apparatus  10  from the top with the upright restraints  30 ,  32  removed. The carousel  16  is positioned parallel to the X-ray cassette  15  at a ninety degree angle as denoted by the numerals  115 . The carousel can be locked into this position by lock  91  or further turned to either the forty-five or thirty degree angle positions and locked. The carousel has a plurality of lock holes  90 , shown in FIG. 3, appropriately located about the edge of the carousel for the lock  91  to engage and secure the carousel  16  at the designated angle positions. The positioner with the uprights removed shows the upright restraint pads  44  attached to the top of the carousel. The wing clamps  34  are attached to the carousel near the end of the upright restraint pads  44  opposite the slide block  40 , and are shown openly positioned to receive the upright restraint wing braces  31 . 
     FIG. 6 b  illustrates the child positioning apparatus  10  from the top with the upright restraints  30 ,  32  engaged. The wing clamps  34  are shown placed over the wing braces  31   a,    31   b  in a closed position. The upright restraints are further restricted from movement by engagement in slide block  40 . FIG. 6 b  shows the wedge  38   b  held to the upright restraint  32  by L-bracket  39   b . The wedge  38   b  is positioned between the slide  46   b  and the divider  41  locking one end of upright restraint  32  into position. Upright restraint  30  is shown similarly fixed into position. 
     FIG. 7 illustrates the upright restraints  30  and  32  with the patient  5  in place on the child positioner  10 . The first upright restraint  30  stands upright resting on L-bracket  39   a . L-bracket  39   a  has wedge  38   a  attached and secured in slide block  40 . Wing brace  31   a  is secured by wing clamp  34 . The upright restraint  30  also has fasteners, such as snap  36 , attached. The fastening mechanism may comprise hook and loop fasteners, but alternatives such as buckles and snaps may be used. The second upright  32  has wing brace  31   b  and L-bracket  39   b . L-bracket  39   b  has wedge  38   b  attached and secured in slide block  40 . Upright restraint  32  also has fasteners, such as, buckle  35  attached to the upright restraint  32 . The strap  37  can be attached by connecting it at snap  35  on left upright  30  and passing to the buckle on the right upright  32 , or the strap  37  may be wrapped completely around both upright restraints three-hundred and sixty (360) degrees and fastened a buckle on upright restraint  30  to further secure the infant within the upright restraints when in use. In alternative hook and loop fastener constructions, a strap of loop material may be fastened on upright restraint  30 , and hook material may be fastened on upright restraint  32 . The strap of loop material may merely be fastened over upright restraint  30  to the hook material on upright restraint  32 , or may continue around and be further fastened to hook material on the reverse side of the strap. 
     FIG. 8 illustrates shield and indicator device  75  in isolation. The shield and indicator device  75  is mounted on the top  50  and the opposite side of child  5  from the film positioner  60 . Indicia plate guide  70  secures a shield such as lead plate  73  by another pass through friction fastener, such as dial knob  80  with threaded shaft  81  passing through groove  76  on mounting plate  72 . The threaded shaft  81  passes through opening  71  on guide  70 , and into or through threaded opening  79  shown in a block attached to the side of top  50 . Twisting the dial knob  80  thus increases or decreases friction between the knob  80  and the mounting plate  72  against guide  70 . Lead indicia markers  74  and cast resin pieces are rotated to expose a position reading over lead plate  73  thereby providing relevant position information on an X-ray photograph. The mounting plate  72  may be adjusted to position the lead shield  73  to protect the reproductive organs of the child  5  being X-rayed or imaged. 
     FIG. 9 a  shows the lock  91  on top  50  disengaged from the carousel  16 . Lock hole  90  is shown outlined on the carousel  16  with the lock shaft  92  positioned for entry upon lifting of lock tab  93 . FIG. 9 b  shows the lock  91  engaged into the carousel  16  with the lock shaft  92  penetrating the lock hole  90  and the lock tab  93  lifted to a closed position. 
     Although a preferred embodiment of the present invention has been disclosed herein, it will be understood that various substitutions and modifications may be made to the disclosed embodiment described herein without departing from the scope and spirit of the present invention as recited in the appended claims.