FI67780C - STOEDARRANGEMANG VID EN PANORAMAROENTGENAVBILDNINGSANORDNING - Google Patents

Description

* 1 67780

SUPPORT ARRANGEMENT IN A PANORAMIC X-RAY IMAGE DEVICE -STÖDARRANGEMANG VID EN PANORAMARÖNTGE NAVBIL DN INGSANORDN ING

The invention relates to a panoramic X-ray imaging device according to the preamble of claim 1.

Conventionally, in panoramic imaging of the head, an imaging device, such as a film cassette, and an X-ray source are rotated on a common support arm around the subject, whereby the subject, a curved layer such as a dentition, is imaged applied in the same plane. In order to make the X-ray beam pass through the layer to be imaged as perpendicularly as possible (the so-called orthogonality condition), the panoramic devices utilize various auxiliary movements by means of which the position of the center of rotation of the X-ray beam can be moved during imaging. In practice, the general auxiliary movement occurs linearly parallel to the median plane of the patient.

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For precise positioning and reliable support of the patient's head, forehead and side supports are needed to keep the head in the correct position and position relative to the body during imaging. In known solutions, these supports 20 are generally attached to the body of the device through a rotating support arm (cf. e.g. FI patent 56621), as support from elsewhere would be cumbersome and the necessary additional support arms would be in the way of the description. Said bushing has an opening made in the support arm, the diameter of which is the length of a linear auxiliary movement for the arms of the main supports. In practice, such a bearing is difficult to implement and can make it difficult to support and guide the support arm firmly.

The object of the invention is to provide a new, reliable and simple solution in terms of structure and function for supporting the head of a patient to be imaged on the body of the apparatus and for hanging and supporting the imaging means.

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It is also an object of the invention to provide a patient head support solution that allows the patient head to be positioned relative to the body of the apparatus prior to imaging so that the location of the sharply drawn layer can be selected by that arrangement.

The objects of the invention are achieved as further specified in claim 1 and claims. The solution according to the invention allows the rotational movement 10 and the linear auxiliary movement of the imaging means, without it being necessary for the support arm to provide a guide opening for the head support means along the length of said auxiliary movement. The invention also avoids impractical and expensive solutions in which the shooting movements and the head-setting movements have separate movement elements.

The invention will now be described in more detail with reference to the accompanying drawing, the sole figure of which shows a preferred embodiment of the invention in principle.

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In the drawing, reference numeral 1 denotes the body of the device and 2 a support arm rotatable around the object, i.e. the patient's head, at the ends of which imaging means, e.g. film 25 cassette 4, and X-ray source 3 supported on the frame 1. Correspondingly, the head support means 6 is supported on the suspension unit 5 by a linear bearing 12. Of the head support means 30, only the headrest is shown in the figure, but may also comprise headrests which can be arranged to press against the patient's head and center the head laterally.

The device also comprises a flexible guide member 7, which may advantageously be a wire, and wire guide rollers 8a and 8b rotatably mounted on the suspension unit 5.

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As shown in the figure, the wire is guided through the guide rollers 8a and 8b between the head support means 6 and the support points of the body 1 so that the indicated linear movement of the arrows of the suspension unit 5 can take place without changing the position of the head support means 6 relative to the body 1.

By using the rollers 10a and 10b to support the wire 7 on the frame 1 and further forming a loop of the wire 7 as shown in the figure, the wire 7 can be moved relative to the frame 1 by means of the lever 9. If desired, the headrests 6 move relative to the frame 1, respectively. This transfer movement can be advantageously used in the pre-imaging positioning of the patient with respect to the apparatus and thus in the selection of a sharply drawn layer.

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In addition to the above, the invention can also be applied in practice with completely different movement members, for example by using toothed rods supported on the body 1 and head support means and arranging a common toothed shaft passing through the support arm 2 to roll along the rackets. However, such a solution is considerably less expensive in terms of manufacturing costs compared to the solution of Figure 1. If it is still desired to carry out said pre-positioning of the head restraint means with respect to the body, the rack must be separately wound on the body. This makes the solution complicated, as the device must also be provided with moving members in order to achieve a linear movement during the actual shooting.

The invention is not limited to the embodiments described above, but several variations are conceivable within the scope of the appended claims.

Claims (3)

4 67780 PATENT SUCTION KITS A support arrangement in a panoramic X-ray imaging device comprising a fixed body (1), a support arm (2), at the ends of which an X-ray source (3) and imaging means (4), for example a filter cartridge, are supported on opposite sides of the subject, and arranged to perform rotation and linear movement relative to the body (1), and head support means (6) for supporting and positioning the patient's head relative to the device, characterized in that the body (1) comprises a suspension unit (5) linearly displaceably supported in the medial plane of the patient supported in a linearly linear manner and in which the support arm (2) is rotatably mounted, and further comprising means (7, 8) for compensating for movement of the suspension unit (5) relative to the body (1) by a corresponding but opposite movement of the head restraint means (6) so that the head support means (6) remain with respect to the body (1) during imaging in place. Support arrangement according to claim 1, characterized in that said movement compensating means comprise a flexible strip-like guide member (7), for example a wire fixed to the head support means (6) at two points in the direction of said linear movement spaced apart and guided by a suspension unit (5) the body (1) at two points respectively and preferably so as to form a unitary, closed loop with respect to the head restraint means (6), that the suspension unit (5) is rotatably mounted for guide member (7) with guide rollers (8a, 8b) or the like and the flexible guide member (7) is arranged to be guided through the guide rollers (8a, 8b) from their opposite sides so as to connect the support points of the head support means (6) and the body (1) crosswise allowing the linear movement of the body (1) and the head support means regarding. 5,67780 Support arrangement according to claim 2, characterized in that it comprises means (9, 10} for moving the strip-like guide member (7) relative to the support points in the body (1) so that the head support means (6) can be moved relative to the body (1) before the rotation. imaging for patient head positioning 67780 6