The invention relates to an x-ray examination apparatus comprising a stand and a support mounting which are adjustable in space, or relative to one another, such that a curved support, mounted on the support mounting is three dimensionally adjustable. At one end of the curved support a radiation source is mounted and at its other end an image layer carrier is mounted so that these units are aligned relative to one another. The support is rotatable about a first shaft. For each of the translational and rotational movements, a drive is provided. In order to obtain an x-ray examination apparatus which is simple in construction and therefore inexpensive, the support is nondisplaceably mounted on the support mounting and is pivotally mounted about an additional shaft disposed horizontally and vertically to the first shaft on the front end of the support mounting.

BACKGROUND OF THE INVENTION 
The invention relates to an x-ray examination apparatus comprising a column 
and a support-mounting which is adjustable in a vertical direction in 
relation to the column, and which holds a curved support at the one end of 
which a radiation source and at the other end of which an image layer 
carrier are mounted in alignment with one another. The support is 
rotatably mounted about a shaft, and a drive is provided for each of the 
translational and rotational movements. 
U.S. Pat. No. 4,150,297 and British Pat. No. 2,098,440A, both incorporated 
herein by reference, disclose x-ray examination apparatus of this type 
wherein an x-ray tube and an x-ray image intensifier are mounted on 
oppositely disposed ends of a semicircularly curved support. The 
semicircularly curved support is displaceable on a support-mounting along 
a track at its circumference. In order that the semicircular support can 
be satisfactorily displaced in the support mounting, both must be 
manufactured with high precision. This is costly and makes the x-ray 
examination apparatus much more expensive. 
SUMMARY OF THE INVENTION 
An object of the invention is to produce an x-ray examination apparatus of 
the type initially cited which is simpler in construction and therefore 
cheaper than the conventional x-ray examination apparatus. 
In accordance with the invention, this object is achieved in that the 
length of the support mounting, i.e. the distance of the front end of the 
support-mounting from the stand, is adjustable, and that the curved or 
bent support is pivotally mounted to an additional shaft, disposed 
horizontally or vertically depending upon orientation relative to the 
first shaft on the front end of the support mounting. Through these 
various parts of the x-ray examination apparatus it is no longer necessary 
to employ an expensive, semicircularly curved support. The support can now 
be designed in a bent shape in a U- or V-formation, which is far simpler 
in terms of manufacture and therefore makes the apparatus cheaper. In 
addition, no curved rail matched to the support is required. 
In the case of an x-ray examination apparatus designed in accordance with 
the invention, it is proposed that the length of the support mounting be 
adjustable. It is therefore achieved that the stand need be mobile only in 
one plane. If the support mounting, in addition, is displaceable or 
pivotal relative to the stand, the necessary movement of the stand is 
reduced to one direction. 
In view of a structurally simple adjustment of the length of the 
support-mounting it is advisable to design the latter in the form of a 
telescope. Alternatively, the support mounting can be designed in the form 
of a two-part articulated arm. 
In an expedient embodiment of the invention, it is proposed that the 
support mounting be pivotally mounted on the stand in a vertical direction 
about a shaft. This makes it possible for the stand to be kept low. 
In order that the support is pivotal in obstructed fashion over a large 
angular range, in a structurally advantageous embodiment of the invention, 
the support is laterally secured to the front end of the support mounting. 
In an advantageous further development of the invention, it is provided 
that, for each adjustment movement, rotational movement, or pivot 
movement, a drive and a position sensor are provided. The signals of the 
position sensors are transmitted to a control device which, given a 
specified isocenter, in the case of a position change in one direction 
determines controlled variables for the other drives in such a fashion 
that, through their actuation, the isocenter is again adjusted. Through 
this technique, it is made possible that the support can be controlled in 
such a fashion that, independently of the course of movement of the x-ray 
tube, or of the image intensifier respectively, the isocenter can always 
be maintained.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
FIG. 1 shows an x-ray examination apparatus comprising a stand 1 which can 
be guided on floor rails 2 in a longitudinally displaceable fashion and 
parallel to a patient support table 3. 
Vertically adjustably mounted on the stand 1 is a telescopic support 
mounting 4 for a U- or V-shaped curved or bent support 5. The support is 
pivotally mounted about a shaft or axle 6, and is secured perpendicularly 
to the longitudinal direction of the support mounting 4 at its front end 
via end part 50. The curved support 5 can also be directly secured to the 
shaft 6. The support 5 is preferably laterally secured on the front end of 
the support mounting 4. On the one terminating end of the support 5 an 
x-ray tube 7 is mounted, and on the other terminating end, an image layer 
carrier 8 is mounted. The x-ray tube 7 is centered with its central ray 9 
aimed at the image layer carrier 8. The support is, in addition, rotatably 
mounted about a shaft or axle 11 which is attached to the end part 50 
which is in turn connected by the shaft 6 to an extension of the 
supporting shaft 10 of the support mounting 4. The support mounting 4 is 
also designed in the form of a telescope, so that its length in a 
horizontal direction is adjustable. 
In FIG. 2, it is illustrated that, for each adjustment movement, rotational 
movement, or pivot movement of the apparatus parts, a drive and a position 
sensor are provided. Thus, the stand 1 is controlled by a motor 12 and a 
position sensor 13. The height adjustment of the telescopic support 
mounting 4 proceeds by use of a motor 14 and a position sensor 15, and the 
length of the telescopic support mounting 4 is adjusted by a motor 16 and 
a position sensor 17. An additional motor 18 and the position sensor 19 
control the pivot movement of the support 5 about the shaft 6. Finally, a 
motor 20 and a position sensor 21 for the rotation of the support 4 about 
the shaft 11 is provided. 
Serving as control device 22 for the motors 12, 14, 16, 18, 20, and the 
position sensors 13, 15, 17, 19, 21, is a computer 23 and a control device 
24. Connected to the control device 22 is a control console 25 whereby the 
position of the x-ray tube 7, or of the image layer carrier 8, are 
respectively controlled. Such a control device with control console is 
disclosed in U.S. Pat. No. 4,019,059, incorporated herein by reference, 
and will therefore not be described in greater detail. 
If a position change of the x-ray tube 7, or of the image layer carrier 8 
is to be conducted, selective motors 12, 14, 16, 18, and 20 are activated 
by the control console 25. The signals of the position sensors 13, 15, 17, 
19, and 21 are supplied via connections 26-30 to the control installation 
22. The control installation 22, then, given a specified isocenter 31, 
supplies via the connection lines 32-36, control variables to the 
remaining motors 12, 14, 16, 18, and 20 in such a fashion that, through 
their activation, the isocenter 31 is maintained. If the support 5 is now 
to be rotated through 90.degree. so that the x-ray tube 7 and the image 
layer carrier 8 assume the position illustrated in broken lines, the motor 
18 is activated via the control console 25 in order that the support 5 is 
pivoted about the shaft 6. The control installation 22 then, in the 
described manner, controls the additional motors 14 and 16 such that the 
preadjusted isocenter 31 is maintained in the case of the position change 
of the x-ray tube or of the image layer carrier, respectively. The motors 
14 and 16 cause the support-mounting 4 to be lowered and the telescopic 
arm to be moved outwardly. In a corresponding fashion, in the case of 
other desired movement paths, also the displacement of the stand 1 is 
controlled and the support 5 is rotated about the shaft 11. The isocenter 
31 need not here be the geometric center between x-ray tube 7 and image 
intensifier or carrier 8, but can lie in varying positions, depending upon 
the adjusted enlargement. It is likewise possible, with the aid of the 
control, to shift the isocenter 31 in a randomly disposed object plane 
while the enlargement remains the same. With the aid of a memory not 
illustrated, it is further possible to retain the necessary data for a 
specific position of the apparatus and, after a random displacement, to 
automatically again adjust the initial position. 
In FIG. 3, an additional embodiment of the x-ray examination apparatus of 
the invention is illustrated. In this sample embodiment, the support 5 is 
held by means of a two-part articulated arm 37. For the adjustment of the 
two parts relative to one another, a motor 38 is provided. The further end 
of the arm 37 is pivotal in the stand 1 about a shaft 39 by means of a 
motor 40. Associated with the motors 38, 40 are non-illustrated position 
sensors which are connected to the control installation (FIG. 2). Through 
the mounting and movement of the arm 37, the stand 1 can be kept low in 
this embodiment. 
In FIG. 4, the telescopic support mounting 4 is pivotally mounted about a 
shaft 41 in the stand 1. As a drive and control, a motor 42 and a 
non-illustrated position sensor are employed, which are connected to the 
control installation shown in FIG. 2. The stand 1 can also be kept low in 
this embodiment through the support mounting 4. 
FIG. 5 finally shows an x-ray examination apparatus comprising a stand 43 
which runs both on floor rails as well as on ceiling rails 44, 45, and on 
which a stand carriage 46 is guided in a longitudinally displaceable 
fashion. The telescopic support mounting 4 is arranged in fixed fashion on 
the stand carriage 46. 
The movement of the x-ray examination apparatus, which proceeds through the 
length-adjustable support mounting 4, or the articulated arm 37, can be 
replaced by a corresponding displacement of the stand 1, 43. This can 
proceed such that, in this direction, known and therefore non-illustrated 
rails are laid on the floor or on the ceiling. The stand 1, 43 drives on 
these rails. It is advantageously also possible to merely suspend the 
stand 1, 43 from the ceiling. 
Through the x-ray examination apparatus of the invention, with the x-ray 
tube, or the image layer carrier, respectively, a spherical movement path 
can be conducted since the movements of the apparatus parts are 
mechanically decoupled and the various movement paths are synchronously 
controlled via a control installation. Through the movement paths of the 
apparatus parts, also the support can be manufactured in a simple and 
cheap form. 
Although various minor changes and modifications might be proposed by those 
skilled in the art, it will be understood that I wish to include within 
the claims of the patent warranted hereon all such changes and 
modifications as reasonably come within my contribution to the art.