DETAILED DESCRIPTION

[0022] Referring to FIG. 1, a positioning stand 10 is provided for a digital radiographic digital imaging device A. A suitable such imaging device that is mountable to the stand 10 is the Xplorer 1700 manufactured by Imaging Dynamics Company Ltd.

[0023] Imaging devices like the Xplorer 1700 are used in medical applications for taking x-ray images of patients. The stand 10 can be articulated to position the imaging device A to take an x-ray of a patient in either a standing or a recumbent position. If the patient is placed on an examination table (not shown) in a recumbent position, the stand 10 positions the imaging device A as shown in FIG. 1, wherein the imaging device A is positioned low enough to slide under the table and rotated such that a scintillator B and a detector face of the imaging device A is facing upwards at the recumbent patient. If the patient is standing (e.g. to take a chest x-ray), the stand positions the imaging device A as shown in FIG. 2, wherein the imaging device is positioned at a height corresponding to the part of the body being imaged (e.g. chest height for chest x-rays) and rotated such that the scintillator B is facing the patient.

[0024] Referring to FIG. 13, when the patient is in position and a part of the patient's body selected for imaging has been set in place, an x-ray source 100 is turned on and x-rays are directed towards the patient. X-rays passing through the patient are captured by the imaging device 102 and converted into a digital x-ray image. In particular, the x-ray image reaching the imaging device 102 is first converted into visible light by the scintillator 104. The visible light is then reflected by a mirror 106 towards lenses in a lens assembly 108, which reduces and directs the visual image onto the surface of a charge coupled device (CCD) camera 110, which converts the visual image into a digital image. The digital image is then transmitted to a computer 112 for imaging processing and storage.

[0025] Referring to FIG. 1, the key major components of the stand 10 that enable the imaging device A to be positioned in multiple positions are a tower assembly 12, a clevis 14 vertically movably attached to the tower assembly 12, an imaging device holder comprising a pivot body assembly 16 that is horizontally pivotally attached to the clevis 14 and an imaging device mount assembly 18 that is rotatably attached to the pivot body assembly 16.

[0026] Referring to the partial cut-away figures in FIGS. 3-5 and 6-9, these components can be seen more clearly. The tower assembly 12 includes

[0027] i. a base 19 with means adapted to securely fasten the stand 10 to the floor (e.g. by bolting);

[0028] ii. a tower housing 20;

[0029] iii. a main vertical support member 21 extending vertically from the base 19;

[0030] iv. a pair of vertically extending guide rails 22 attached to the front of the support member 21;

[0031] v. a pulley assembly 26 that includes cables (not shown) that attach at one end to the carriage 50, and at the other end to counterweights 61 that move vertically within a channel 32 at the back of the support member 21;

[0032] vi. a motor 28 attached to the pulley assembly 26; and,

[0033] vii. a guide rail car 52 attached to the carriage 50 and slidably wrapped around the guide rails 22 to help restrict the movement of the carriage 50 in a vertical direction only.

[0034] Referring to FIGS. 6 to 9, the tower assembly components are presented in more detail.

[0035] Stopper assembles 44 are provided at each end of each guide rail 22 to prevent the carriage 50 from sliding off the guide rails 22. Stopper assembles 44 are attached to the tower assembly 12 by bracket 42 and includes stop 46 and 48.

[0036] The carriage 50 is attached to guide rail brackets 52, which are slidable along respective guide rails 22; the tolerances are relatively fine between brackets 52 and rails 22 to prevent any play that might upset the position of the imaging device A and cause binding under motion.

[0037] Referring particularly to FIGS. 8 and 9, a pulley system is used to provide counterweighting of the carriage and the components attached to the carriage 50, i.e. the clevis 14, pivot body assembly 16, mount assembly 18, and imaging device A. This reduces the load on motor 28, and allows for designing a non-motorized stand wherein the vertical position of the imaging device A can be adjusted manually. Of the pulley system, only pulleys 26 are shown attached to the top of the tower assembly 12. Not shown are cables for each pulley that have the carriage 50 attached to at one end, and counterweights 61 attached to at the other end. The counterweights are generally cylindrical to conform to the shape of the channel 32.

[0038] Referring now to FIGS. 10-12, the clevis 14 has a base that is adapted to attach to the carriage 50, and a C-shaped arm 64 extending generally horizontally from the base. The ends of the arm are adapted to receive a pivot assembly 16. The pivot assembly 16 is shown in exploded form in FIGS. 11 and 12 and comprises a number of parts to enable it to pivot about the clevis 14, and to secure it to the arm 64, and to lock the pivot body assembly 16 from pivoting. In particular, vertical solenoid rotation release 70 has pin that is spring loaded in a locked position; when power is applied to the solenoid, the pin is moved into an unlocked position to allow the pivot body assembly 16 to pivot. The pin threads through threaded pin 72. Various seals and bearings 74, 76, 80, 82, 84, 86, 88 facilitate the pivoting of pivot assembly 16.

[0039] The pivot assembly 66 is thus pivotable in the horizontal plane, and has attached thereto the pivot body assembly 16. The pivot body assembly 16 has a main body 98 that is adapted to be pivotably attached to the pivot assembly; locking sleeve 92, pin guide 94, pin 96 cooperate with the rotation release solenoid 70 to lock the main body assembly 16 in place. At the bottom of the main body 98 is attached a sag adjustment system comprising components 102, 104, and 106 that allow an operator to compensate for sagging of the main body assembly 16 caused by the weight of the x-ray imaging device A attached thereto.

[0040] Main body 98 is generally cylindrical and extends along a pivot body axis. The imaging device mount assembly 18 is rotatably attached to an end of the pivot body assembly 16. The pivot body assembly 16 is adapted to allow the mount assembly 18 to rotate about the pivot body axis. The pivot body is shown in exploded form in FIGS. 11 and 12 and comprises the following components:

[0041] a connector face 108 that is adapted to connect to a mating component of the imaging device A;

[0042] a cylindrical plate 110 that fastens against main body 98 to secure crossed roller bearing 112 in place;

[0043] rotational body 114 that is attached to connector face 108 and inner race of roller bearing 112, thereby allowing connector face 108 to rotate relative to the main body 98;

[0044] spline gear 116 that is movable along the main body axis to lock and unlock the mount assembly 18 from rotational movement;

[0045] a cylindrical plate 118 to fasten spline gear within main body 98;

[0046] rotational solenoid assembly that when unpowered, is spring loaded to bias spine gear into a locked position, and when powered, pulls spline gear into an unlocked position.

[0047] When assembled, it can be seen that the components of the stand 10 cooperate to allow the stand to be articulated about three axes, namely the clevis is movable vertically along tower assembly 12, the pivot body assembly 16 is movable pivotably in the horizontal plane about the clevis 14, and the imaging device mount assembly 18 is movable rotatably about the pivot body axis of the pivot body assembly 16. This articulation enables the imaging device A to be precisely positioned to take x-ray images of patients in recumbent, standing, or other positions.

[0048] While the preferred embodiment of the invention has been illustrated and described, it will be appreciated that various changes can be made therein without departing from the scope and spirit of the invention.