U.S. patent number 3,927,326 [Application Number 05/508,469] was granted by the patent office on 1975-12-16 for x-ray examining apparatus.
This patent grant is currently assigned to Siemens Aktiengesellschaft. Invention is credited to Kurt Kunne, Fritz Wittkopp.
United States Patent |
3,927,326 |
Kunne , et al. |
December 16, 1975 |
X-ray examining apparatus
Abstract
An X-ray examining apparatus including a support block which is
mounted so as to be vertically displaceable along the base of the
apparatus; a carrier which is supported on the support block and
rotatable about a horizontal pivot axis and which carries an image
layer or picture target oriented in parallel to the pivot axis; an
X-ray tube which is centered on the picture target; and a removable
and interchangeable patient support located between the X-ray tube
and the picture target.
Inventors: |
Kunne; Kurt (Erlangen,
DT), Wittkopp; Fritz (Weiher, DT) |
Assignee: |
Siemens Aktiengesellschaft
(Erlangen, DT)
|
Family
ID: |
5893509 |
Appl.
No.: |
05/508,469 |
Filed: |
September 23, 1974 |
Foreign Application Priority Data
|
|
|
|
|
Sep 24, 1973 [DT] |
|
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2348039 |
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Current U.S.
Class: |
378/179; 378/21;
378/189; 378/195 |
Current CPC
Class: |
A61B
6/4452 (20130101); A61B 6/548 (20130101) |
Current International
Class: |
A61B
6/02 (20060101); A61B 006/00 () |
Field of
Search: |
;250/444,445,446,447,448,449,445T |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Lawrence; James W.
Assistant Examiner: Grigsby; T. N.
Attorney, Agent or Firm: Waters, Schwartz & Nissen
Claims
What is claimed is:
1. In an X-ray examining apparatus having a pedestal base; a
vertically displaceable support block mounted on said base; a
carrier supported on said support block for rotation about a
horizontal pivot axis; a picture target mounted on said carrier and
being oriented in parallel with said pivot axis; an X-ray tube
being focused on said picture target; and patient support means
interposed between said X-ray tube and said picture target, the
improvement comprising: said carrier for said X-ray tube and
picture target being dually offset in a U-shape in a plane oriented
perpendicular to said picture target, said U-shape forming a first
and a second arm, said first arm supporting said picture target and
being fastened to said support block for rotation about said
horizontal pivot axis, said X-ray tube being fastened to said
second arm having the central X-ray beam thereof directed towards
said picture target; a carrying frame for a patient support
rotatable about an axis parallel to the surface of said picture
target; and a subframe rotatable about the median perpendicular of
said picture target supporting said first arm, said subframe being
longitudinally movably mounted on said carrying frame.
2. An apparatus as claimed in claim 1, said patient support being
movably suported on said carrying frame for displacement normal to
the surface of said picture target.
3. An apparatus as claimed in claim 1, said patient support being
supported on said carrying frame for transverse displacement
relative thereto.
4. An apparatus as claimed in claim 1, said carrying frame having
an end plate facing the foot of said apparatus, said patient
support being mounted on said end plate.
5. An apparatus as claimed in claim 1, said patient support being
detachable and interchangeable with patient supports of specialized
varied types.
6. An apparatus as claimed in claim 1, said carrier for the X-ray
tube and picture target comprising a parallelogram linkage, link
means pivotably supported about a target axis, said target axis
being parallel to the target plane and the linkage axis of said
parallelogram linkage and oriented for adjustability perpendicular
relative to the plane of said picture target; said second arm
supporting said X-ray tube being hingedly connected to one end of
said link means, said link means having the other end thereof
connected to said picture target in the plane of said target and a
projection supporting said X-ray tube for rotation about an axis
oriented in parallel to said target axis, said projection including
an auxiliary linkage for maintaining said X-ray tube directed
towards said picture target.
7. An apparatus as claimed in claim 6, comprising an X-ray image
intensifier connected to said link means and adapted to be moved in
the direction of said picture target.
8. An apparatus as claimed in claim 6, comprising Bucky diaphragm
means connected to said link means and adapted to be moved in the
direction of said picture target.
9. An apparatus as claimed in claim 6, comprising a pair of
follower plates a stage rotatable about the median vertical of said
picture target, said follower plates being mounted along an axis
oriented perpendicular to said target and in synchronism with the
rotation of said stage being displaceably supported parallel to
said target and to the respective longitudinal and transverse
directions of the patient support, said follower plates being
connected to said link means for displacement of adjusting means; a
reference value indicator fastened to said stage connected to said
follower plates, said follower plates including step motors for
actuation thereof and being connected to a servo control for the
corresponding displacement of said patient support relative to said
picture target.
10. An apparatus as claimed in claim 6, said target axis being
oriented in parallel to said pivot axis.
11. An apparatus as claimed in claim 6, said target axis being
oriented in perpendicular to said pivot axis.
12. An apparatus as claimed in claim 1, the rotational velocity of
said patient support about its longitudinal axis and the pivot
velocity of said carrier about the pivot axis being correlated with
each other.
Description
FIELD OF THE INVENTION
The present invention relates to an X-ray examining apparatus
including a support block which is mounted so as to be vertically
displaceable along the base of the apparatus; a carrier which is
supported on the support block and rotatable about a horizontal
pivot axis and which carries an image layer or picture target
oriented in parallel to the pivot axis; an X-ray tube which is
centered on the picture target; and a patient support located
between the X-ray tube and the picture target.
DISCUSSION OF THE PRIOR ART
At present there is known an X-ray examining apparatus having a
support block which is vertically adjustably mounted on the
pedestal of the apparatus, on which there is supported a picture
target carrier and an X-ray tube operatively associated with the
picture target carrier so as to be rotatable about a common
horizontal axis. In this X-ray examining apparatus, a patient
support pallet which is longitudinally and transversely
displaceable, as well as in a direction normal to the surface of
the picture target is separately mounted on the support block. The
examinations which are adapted to be carried out by means of this
known X-ray examining apparatus does not, however, completely
provide the fullest possible technical apparatus requirements.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an
X-ray examining apparatus which is most universally applicable and
adapted to carry out the most varied types of examinations. This
object is based on the knowledge that technical apparatus measures
which have been created for a particular type of examination may,
under circumstances, be utilized for still further types of
examinations by means of only relatively minor additional
requirements. In that connection, a particularly variably
employable X-ray examining apparatus upon careful selection of the
range of application, can be manufactured in a relatively
economical manner.
In an examining apparatus according to the above-mentioned type,
the carrier for the X-ray tube and for the picture target is doubly
offset in the form of a U in a plane which is oriented
perpendicular to the picture target and rotatably supported about
the horizontal pivot axis on the support block through an arm
thereof which carries the picture target, the X-ray tube being
fastened to the opposite arm of the carrier so that its central
beam is centered or focused onto the picture target, and provides a
carrying frame for a patient support which is rotatable about a
longitudinal axis extending in parallel relative to the surface of
the picture target, on which the arm carrying the picture target
supported on an intermediate frame rotatable on the picture target,
is vertically displaceably mounted along a median vertical. This
arrangement facilitates that the patient support together with the
patient, at representable requirements, may be rotated about the
vertical median of the picture target, independently of the
inclined position of the picture target, and to thereby avoid at
all examining positions any collisions with the carrier for the
X-ray tube and the picture target. In connection with the patient
support, which is rotatable about its longitudinal axis, the
tube-picture target system can also be rotated about the patients'
longitudinal axis, so as to permit the taking of transversely
penetrating or radiological exposures in all inclined positions of
the patient support. Thus, for example, through the use of this
X-ray examining apparatus it also becomes possible to transversely
X-ray the patient in any desired inclined position with a
horizontal ray beam.
In a particularly advantageous modification of the invention, the
patient support on the carrier frame may be supported so as to be
displaceable in directions normal to the surface of the picture
target. Thereby, it becomes possible, additionally to also vary the
exposure relationship. This is of particular advantage in the
examination of children, inasmuch as the smaller organs are
represented on the basis measurements usual to adults, and may
thereby be much better compared in the diagnostic position.
A simplification of the construction of the X-ray apparatus is
attained when the patient support, in a suitable embodiment of the
invention, is transversely movably supported on the carrier frame.
This eliminates the necessity that the picture target and the X-ray
tube need be displaced transversely of the longitudinal axis of the
patient, without any further measures having to be applied with
respect to loss of possible types of examinations.
In a particularly advantageous further embodiment of the invention,
there may be utilized a patient support which is fastened to an end
plate of the carrier frame facing towards the footside thereof. A
patient support which is supported along one side thereof does not
only improve accessibility to the patient in the head region, but
above all creates particularly advantageous conditions for further
constructive measures which will increase the range of application
for the X-ray examining apparatus.
Thus, the range of application of the X-ray examining apparatus may
be increased when, in a particularly advantageous embodiment of the
invention, there are employed varied, mutually interchangeable, for
specialized applications adapted, and easily removable patient
supports. This will also permit the use of patient supports which
are dimensioned in conformance with the body sizes of particular
patient groups such as, for example, children of various ages. Such
specialized patient support with particular dimensions adapted to
the body sizes of the patients facilitate the examination and
considerably easier to manipulate when reduced to the body sizes of
infants. In this manner, the range of application of the X-ray
examining apparatus can be extended to childrens clinics, however,
without being restricted thereto. Moreover, for infants or small
children, the oft time consuming fastening to a corresponding
patient support may be effected remote from the X-ray examining
apparatus, for example, in an adjoining chamber, while a previous
patient is still being examined on the X-ray apparatus. Thus, the
examination sequence becomes more continuous and, above all, the
examining capacity and the therewith connected economic value of
the X-ray examining apparatus in children's clinics is considerably
enhanced. In addition to predetermined patient groups, there may
also be utilized patient supports which are adapted to particular
examining techniques.
An additional significant increase in the range of applicability of
the X-ray examining apparatus can be achieved when the carrier for
the X-ray tube and the picture target, in a further embodiment of
the invention for producing tomographic X-ray exposures, is
constructed in a type of a parallelogram linkage, wherein a known
tomographic rod or linkage is pivotably mounted about a plate axis
extending in parallel with the plane of the picture target, and
oriented with respect to the linkage axis of the parallelogram and
perpendicular to the plane of the picture target, having one end
thereof linked to the X-ray tube carrying arm of the carrier, and
having the other end connected to the picture target in the plane
of the picture target, and the X-ray tube on a boom being rotatably
supported with respect to an axis which is oriented in parallel to
the target axis, and which is directed in association with the
picture target through an auxiliary link connected to linkage of
the picture target. Through this further embodiment of the X-ray
examining apparatus, the entire range of application of tomographic
or layer exposures is encompassed. Thereby is also provided that,
in addition to the longitudinal tomographic exposures usual in
tomographic exposure apparatus, also tomographic exposures in
transverse direction can be carried out. Since it is possible to
make these tomographic exposures in all inclined positions of the
patient, it is also possible to not only three-dimensionally
displace the image plane within the body of the patient by means of
a tomographic exposure apparatus, but to additionally rotate this
plane about two coordinate axes relative to the body of the
patient.
In a further particularly advantageous embodiment of the invention,
there may be utilized an X-ray image intensifier which is connected
to the tomographic linkage and supported so as to be displaceable
in the direction of the target. This has the result that the Bucky
diaphragm which is usually required for tomographic exposures may
be eliminated, and that in lieu of the presently needed, expensive
large-sized film sheets required for tomographic exposures, there
may be employed considerably less expensive small-sized film
through photographic filming of the outlet luminescent screen of
the X-ray image intensifier. This construction leads to a
considerable reduction in the cost of the tomographic exposures, in
a significant manner increases by a multiple the ability to
displace and rotate the sharply imaged plane within the body. This
then frees the physician from any holding back due to reasons of
costs upon application of the above stated tomographic exposure
technology.
BRIEF DESCRIPTION OF THE DRAWINGS
Further details of the invention may now be ascertained from the
following description of various embodiments, taken in conjunction
with the accompanying drawings in which:
FIG. 1 illustrates in perspective, a partly sectional overall view
of an X-ray examining apparatus with an upright patient support and
horizontal X-ray beam:
FIG. 2 schematically illustrates a partly sectional, overall view
of the X-ray examining apparatus in a position for tomographic
exposures in transverse direction for a reclining patient,
FIG. 3 is a sectional view through a detachable patient support
mounted on an end plate of the carrier frame toward the foot facing
side-thereof; and
FIG. 4 is a plan view of a rotatable stage built into the plate
block for the electrical remote-controlled relative displacement of
the patient support during plate movement.
DETAILED DESCRIPTION
Referring now in detail to FIG. 1 of the drawings, there may be
ascertained the base 1 of the X-ray apparatus, on which there is
mounted a vertically displaceable support block 2 for a horizontal
pivot axis 3. Along the horizontal pivot axis there is supported a
U-shaped carrier 4 for an X-ray tube 5 and a picture target 6. The
picture target 6, which in the present instance is the inlet
luminescent screen of an X-ray image intensifier 7, is encompassed
by a rectangular subframe 8, which is supported on the X-ray image
intensifier carrying arm 9 of the U-shaped carrier 4 so as to be
rotatable with respect to the median vertical 10 on the picture
target 6. Along two mutually parallel sides of the subframe 8,
supported displaceably in the longitudinal direction, is a carrier
frame 12 which is correlated with the dimensions of a patient
support 11. On the lower or foot-facing end of the carrier frame
there is supported an end plate 13 which is displaceable in a
transverse direction relative to the carrier frame. Rails 14 are
located at this end plate, which extend perpendicular to the plane
of the picture target (FIG. 3), along which a bearing bushing 15
extending in the longitudinal direction of the carrier frame is
displaceable perpendicular to the plane of the picture target. Onto
this bearing sleeve there is attachedly fastened the rotary-sleeve
like patient support 11. Fastened to the arm 16 of the carrier
which is opposite to the picture target 6 by means of extension 18,
is the X-ray tube 5 with its attached disphragm 17. The U-shaped
carrier is constructed to provide the capability of opposite
parallel displacement of both its arms with respect to each other
in the art of a parallelogram linkage, in which the linkage axis
19, 20, 21, 22 of this parallelogram linkage in the exemplary
embodiment are oriented in parallel with the pivot axis 3. The
extension 18 of the X-ray tube 5 is supported so as to be rotatable
about an axis 23 parallel to the linkage axis of the parallelogram
linkage of the U-shaped carrier 4. To the arm 16 of the U-shaped
carrier 4 carrying the X-ray tube 5 there is hingedly connected a
tomographic rod or link 24 which is connected, so as to be
pivotable about a tomographic axis 27 which is vertically
adjustable with respect to a plate or target support block 25 along
a spindle 26. An auxiliary link 28 is fastened to the tomographic
link 24, by means of which the X-ray tube 5 may be pivoted about
the axis 23 of the arm 18 and directed towards the picture target
6. At the free end of the link 24 which is opposite to the X-ray
tube, there is connected a so-called coupling link 29 in the plane
of the picture target through the intermediary of which the picture
target, in the present instance this also being the X-ray image
intensifier 7, may be displaced interiorly of the subframe 8 in
correspondence with the target movement relative to the arm 9 of
the carrier which is hinged at the pivot axis 3.
FIG. 2 illustrates the X-ray examining apparatus for the formation
of X-ray plates of transverse tomographic movement. This position
of the X-ray examining apparatus is achieved, as indicated from the
position shown in FIG. 1, through inclination of the X-ray
examining apparatus about the pivot axis 3, through the concurrent
rotation of the subframe 8 about the median perpendicular 10 on the
picture target 6, and the patient support 11 about its longitudinal
axis 30 by respectively 90.degree..
Through an illustrative cut out in the covering of the plate block
25 there may be ascertained the spindle 26, along which a screw
bolt 31 with the horizontal tomographic axis 27, about which the
tomographic link 24 is rotatably supported, is vertically
adjustable. At the free end of the plate link there may also be
ascertained an elongate aperture 32 into which a coupling link 29
projects for displacement of the X-ray image intensifier 7 in the
plane of the picture target.
In the representation of FIG. 3, the end plate 13 facing towards
the foot of carrier frame 12, which is displaceable transverse to a
table frame, is rigidly connected with an additional patient
support pallet 33 which is also transversely displaceable on the
carrier frame. For purposes of illustrative clarity, the patient
support plate is not shown in FIGS. 1 and 2 of the drawings. In the
illustrated broken-through section of the housing of the end plate
13 facing towards the foot-side of the carrier frame 12, there may
be ascertained one of two rails 14 which extend in perpendicular to
the plane of the carrier frame (only one illustrated), along which
a carriage 34 is movable through the intermediary of a spindle 36,
which is driven by a motor 35. The carriage supports the bearing
bushing 15, the latter of which extends in parallel with the plane
of the carrier frame 12 and is rotatable about its own longitudinal
axis. Within this bearing bushing there may be provided the various
patient supports 11 (only one illustrated) which are associated
with the X-ray examining apparatus, the supports having at their
foot-facing end, measured in cross-sectional correlation with the
smaller width of the bearing bushing, support stub shaft 37 adapted
to be slipped into the bushing. In the section of the foot-facing
end plate of the carrier frame there may further be ascertained an
additionally motor 38 which is fastened onto the carriage 34, and
by means of which the bearing bushing 15 and, consequently, the
particular patient support 11 having its stub shaft 37 in the
bearing bushing, are rotated about their longitudinal axis by means
of a chain drive 39. In the sectionally shown portion of the
foot-facing support stub shaft 37 of the patient support 11 there
may be ascertained a pivotally supported, spring-loaded lock 40
which, upon a fully inserted patient support, engages in a recess
41 in the bearing bushing, and to thereby protect the patient
support 11 from inadvertent falling out.
In order to remove the patient support, the lock 40 may be
withdrawn by the opening of a clamp 42 located on the foot-facing
end of the rotational sleeve through manipulation of the mutually
interengaging projections 43, 44 of clamp 42 and lock 40.
During the X-ray examinations of upstanding patients, the patient
may stand on the foot-facing face plate of the patient support 11
in the position of the X-ray examining apparatus as shown in the
representation of FIG. 1. For examination of a patient in a
horizontal position or in a lowered head position, it is adequate
to pivot the U-shaped carrier 4 for the X-ray tube 5 and the
picture target 6 about the horizontal pivot axis 3. By means of the
concurrent longitudinal displacement of the carrier frame 12
relative to the subframe 8, and through displacement of the
foot-facing end plate 13 transverse of the carrier frame, all parts
of the patient become accessible for X-ray examination. For
radiological examination of the patient in a transverse direction,
the patient support 11 must be rotated for about 90.degree. about
its longitudinal axis on the foot-facing end plate 13 of the
carrier frame 12. Through additional rotation of the subframe 8
about the normal 10 to the picture target 6, the inclined position
of the patient may be varied in accordance with any particular
requirements. Changes in the filming proportions may be obtained
when the patient support is displaced in perpendicular to the plane
of the picture target through the spindle drive 35, 36 within the
foot-facing end plate 13 of the carrier frame 12. With an
increasing distance of the patient support from the picture target
plane the magnification increases. In all of these positions the
patient may be X-rayed from forwardly, from the side or from
rearwardly, through rotation of the patient support about its
longitudinal axis.
The freely exposed mounting of the patient support 11 on the
foot-facing end plate 13 of the carrier frame 12 does not only
improve the access to the patient, but also renders easier the
exchange of the patient support with another patient support. This
is particularly applicable when the patient support which provided
at the foot-facing end thereof with the support projection 37, as
shown in FIG. 3, is merely slid into one of the foot-facing bearing
bushings 15 in the end plates 13 of the carrier frame. Due to the
easy exchange of the patient supports, in addition to patient
supports for adults, also those for infants and, upon occasion,
also for special types of examinations, may be mounted on the
foot-facing end plate of the carrier frame. Smaller patients
supports are of particular advantage during the examination of
children, since the children are better supported therein, and the
accessibility to the patient, in contrast with the larger patient
supports conceived for adults is much more readily resolved. There
are also much better provided with support means which are
particularly designed for children, as if they had to be
concurrently utilized for adults. Above all, children may be
already fastened onto one of the patient supports in an adjoining
chamber prior to the examination. These patient supports, with the
infant thus fastened thereto need, for examination, only be slid
onto the foot-facing end plate 13 of the carrier frame of the X-ray
examining apparatus. Consequently, the X-ray examining apparatus is
not far as long as previously blocked off by such ancillary
operations.
In view of the configuration of the U-shaped carrier 4 as a
parallelogram linkage, the arm 16 supporting the X-ray tube 5, and
the arm 9 supporting the picture target 6 extend in parallel to
each other and are displaceable relative to the picture target. By
means of the tomographic link 24 and the auxiliary link 28 hinged
thereto, the X-ray tube is constantly supported so as to be
directed towards the examining object which is located in the plane
of the tomographic axis 27. As a result of the connection of the
picture target carrier with the free end of the tomographic link 24
through coupling link 29, the picture target is also concurrently
directed towards the main or central beam 45 of the X-ray tube 5.
Thereby, in view of the rotation of the subframe 8 about the median
perpendicular 10 on the picture plate 6, it becomes possible to
effect tomographic exposures in a patient's longitudinal as well as
in the patient's transverse directions, and in all intermediate
directions and namely in all inclined positions of the patient
around its longitudinal axis and of the central beam 45 of the
X-ray tube 5 around the horizontal pivot axis. In that case the
target plane within the patient cannot only be displaced
three-dimensionally, but may also be rotated about two coordinate
axis. In the embodiment of FIGS. 1 and 2, the patient remains at
rest during the X-raying sequence, and the X-ray tubes 5 and the
picture layer are oppositely moved. In lieu of a Bucky-diaphragm
59, however, the X-ray image intensifier 7 is moved. This provides
the possibility, through a photographing of the outlet luminescent
screen of the X-ray image intensifier, that the expensive
large-sized tomographic exposures may be replaced by considerably
less expensive small-sized films.
Instead of the displacement of the picture target 6 relative to the
patient during the X-raying sequence, it is also possible that the
picture target 6, in the present instance also the X-ray image
intensifier 7, is fixedly fastened to the lower arm 9 of the
parallelogram linkage of the U-shaped carrier 4, and to displace
the patient the X-raying sequence relative to the picture target 6.
Herein, for effecting displacement of the patient, there may be
employed the step motors 46, 47 to impart longitudinal and
transverse displacement to the patient support 11. Upon rotation of
the carrier frame 12 of the patient support 11 about the median
perpendicular 10 of the picture target 6, consideration must be
given that the movement of the patient support during the X-raying
sequence constantly remains parallel to that of the X-ray tube 5.
In accordance with the rotational angle in which the patient
support is rotated about the median perpendicular 10 of the picture
target 6, this signifies that the path of the tomographic link 24
must be resolved as respectively a component in the transverse and
longitudinal directions of the patient support 11. For this purpose
FIG. 4 illustrates a stage 48 adapted to be built onto the plate or
target support block 25 in a plane extending parallel to the
picture plate 6, which is rotatably supported in synchronism with
the patient support, and supporting two follower plates 49, 50
which are displaceable at right angles relative to each other. Both
follower plates 49, 50 are each provided transverse to their
direction of displacement with a longitudinal slot 51, 52 in which
the tomographic link 24 can slide. Both of the follower plates,
futhermore, are provided with a gear rack 53, 54. Each of these
gear racks is, respectively, in operative engagement with a pinion
55, 56, which are fastened to an axle of a mechanical-electrical
converter 57, 58 located on the stage 48. Through the intermediary
of these two converters there is produced one of the positionings
of the respective follower plates 49, 50 on the stage 48 in
conformance with an electrical reference value.
The stage 48 is connected with the subframe 8 through a gear chain
drive (not shown) so that the direction of displacement of one of
the follower plates 49 during the rotation of the subframe remains
parallel to the longitudinal direction of the patient support 11,
and the other follower plate 50 remains oriented in parallel to the
transverse direction of the patient support. The converter 58,
which is set by the follower plate 50 which displaceable in the
transverse direction with respect to the patient support 11 is,
together with the step motor 47 and a further similar actual value
indicator coupled to the step motor 47, a component of a servo
control (not shown). The same also applies to the converter 57,
which is adjustable by means of the follower plate 49 which is
displaceable in the longitudinal direction of the patient support,
the step motor 46 for the longitudinal displacement of the patient
support 11 and an actual value indicator connected to this
motor.
The rotatable stage 48 facilitates that the stroke of the plate
link 24 during the X-raying sequence be divided into a component in
the longitudinal direction and a further component in the
transverse direction of the patient support 11. The patient support
11 is, during the X-raying sequence, moved by means of converter
57, 58 in accordance with a servo control for the transverse and
longitudinal direction converters of the patient support associated
converter, and the present motors 46, 47, for the longitudinal and
transverse displacement of the patient support. This arrangement
has the particular advantage that it facilitates operation with
X-ray image intensifiers 7 having large inlet luminescent screens,
for which there in particular would be no space in the subframe 8
for sufficient displacement in the target direction. In this
embodiment the target axis 27 is rigidly supported on the plate
support block in the plane of the picture plate 6, and the stage 48
with the spindle 26 is carried along the tomographic link 24
displaceable in the target height.
When the drive for effecting the rotation of the patient support 11
about its longitudinal axis 30 and for the pivoting of the carrier
4 about the horizontal pivot axis 3 are mutually adjusted in the
sense of providing values having equal rotational velocities, it is
possible to attain, through opposite rotational motion of the
patient support and carrier, that the X-ray tubes and the picture
target rotate about the longitudinal axis of the patient without
the last-mentioned being rotated with respect to the chamber. In
this setting, which may be effected by means of a therefore
provided switch, in the X-raying of contrast media-filled organs,
the contours of the latter may be controlled in a particularly good
manner.
While there has been shown what is considered to be the preferred
embodiment of the invention, it will be obvious that modifications
may be made which come within the scope of the disclosure of the
specification.
* * * * *