JP3472626B2 - Gantry - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates to X-ray CT (Computed Tomogra
phy) gantry.

[0002]

2. Description of the Related Art Next, a conventional gantry will be described with reference to the drawings. FIG. 8 is a front sectional configuration diagram of a conventional gantry, and FIG.
FIG. 9 is a sectional view taken along the line AA in FIG. 8, and FIG. 10 is a diagram showing a head-first scan which is one mode during inspection with the gantry shown in FIG.

In FIGS. 8 and 9, 1 is a cover in which a subject insertion hole 2 is formed, 3 is provided in the cover, rotates around the subject insertion hole 2, and is fan-shaped toward the subject insertion hole. Radiation generating means 4 for emitting the radiation of
It is a radiation detection unit that is arranged to face the radiation generation unit 3 through the subject insertion hole 2 and rotates around the subject insertion hole 2 in the same positional relationship as the radiation generation unit 3 to detect radiation.

Reference numeral 5 denotes a disk-shaped slip ring which is provided in the cover 1 and which supplies power to the radiation generating means 3 and the radiation detecting means 4 and sends and receives signals. 6 is a slip ring 5
The reference numeral 7 designates a power source brush which is slidably contacted with the slip ring 5, and 7 is a signal system brush which slidably contacts the slip ring 5.

In FIG. 10, reference numeral 8 denotes a cradle for mounting the subject 9 in the subject insertion hole 2 of the gantry. next,
The operation of the above configuration will be described. Radiation is emitted from the rotating radiation generation means 3 to the subject 9 placed in the subject insertion hole 2 using the cradle 8. The radiation that has passed through the subject 9 is detected by the radiation detecting means 4. The radiation detecting means 4 outputs an electric signal (projection data) according to the intensity of the radiation. The radiation generating means 3 makes one rotation to obtain projection data from the multiple directions on the subject 9 to form a tomographic image.

[0006]

In the gantry having the above structure, as shown in FIG. 10, when head-first scan is performed, the gantry 1 blocks the upper field of view of the subject 9 and gives the subject 9 a sense of closure. There is a problem.

Further, as shown in FIG. 11, the subject's knee may be bent and the gantry may be tilted for scanning. At this time, the gantry comes into contact with the knee of the subject, the tilt angle of the gantry is limited, and there is a problem that scanning in a wide tilt range cannot be performed.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a gantry that does not give a feeling of closure to the subject and has a wide tilting range.

[0009]

The invention for solving the above-mentioned problems is to provide a cover in which a subject insertion hole is formed, and a cover provided in the cover and rotated around the subject insertion hole to insert the subject insertion hole. Radiation generating means that emits radiation toward the hole, and the radiation generating means and the object insertion hole are opposed to each other in the cover, and the same positional relationship as the radiation generating means around the object insertion hole. Rotate while holding
In the gantry including the radiation detecting means for detecting the radiation, a recess is formed on an upper surface of a surface of the cover where the opening of the subject insertion hole is formed.

A slip ring mechanism using a disk-shaped slip ring for supplying power to the radiation generating means and the radiation detecting means and transmitting and receiving signals is provided in the cover, and the cover is attached to the main frame. And a front cover that is detachably attached to the main frame, has an opening for the subject insertion hole formed therein, and is provided on the side facing the table, and is detachably attached to the main frame. It is preferable in terms of maintenance and inspection that the slip ring is provided on the rear cover side and the recess is formed in the rear cover.

Further, it is desirable to dispose the brush of the slip ring in the lower part of the gantry in order to form a wider range of recesses.

[0012]

In the gantry of the present invention, while the radiation generating means and the radiation detecting means rotate around the subject insertion hole, the radiation generating means irradiates the subject with radiation, and the radiation transmitted through the subject is radiated. The detection means detects.

Since the concave portion is formed on the upper surface of the surface where the opening of the subject insertion hole is formed, the range in which the upper visual field of the subject is blocked is reduced, and the subject is not given a sense of closure. Further, since the concave portion is provided, the tilting range of the gantry is expanded.

Power supply and signal transmission / reception to / from the radiation generating means and the radiation detecting means are performed via a slip ring mechanism. 3 of main cover, front cover and rear cover
Since the front cover and the rear cover are detachable, the device inside the cover can be easily inspected and maintained.

By providing the slip ring on the rear cover side and forming the concave portion on the rear cover, the concave portion can be formed, the upper field of view of the subject is widened during the head first scan, and the gantry during the foot first scan is widened. The tilting range can be expanded.

By disposing the brush of the slip ring in the lower part of the gantry, it is possible to form a concave portion in a wider range, further, the subject is not given a feeling of being closed, and the tilting range of the gantry is further widened.

[0017]

Embodiments of the present invention will be described with reference to the drawings. First, a first embodiment will be described with reference to FIGS. FIG. 1 is a front view for explaining an essential part of a first embodiment of the present invention, and FIG. 2 is a sectional view taken along line BB in FIG.

In these figures, 11 is a lower frame fixed to the floor side. A main frame 12 is provided so as to be tiltable with respect to the lower frame 11. Reference numeral 13 denotes a rotary casing rotatably provided with respect to the main frame 12.

14 is attached to the main frame 12,
It is a cover in which the subject insertion hole 15 is formed. Cover 1
Reference numeral 4 designates a main cover 16 attached to the main frame 12, a front cover 17 detachably attached to the main frame 12, an opening for a subject insertion hole 15 is formed, and a front cover 17 provided on the side facing the cradle. The rear cover 18 is detachably provided on the frame 12 and has an opening for the subject insertion hole 15. The side portion of the main cover 19 is removable.

The rotating casing 13 has an object insertion hole 1
5, a radiation generating means 20 for emitting the radiation toward the radiation 5, and a radiation detecting means 21 for detecting the radiation, which are arranged opposite to the radiation generating means 20 through the subject insertion hole 15.

Further, on the side of the rear cover 15 of the rotary housing 13, there is provided a slip ring mechanism 22 for supplying electric power to the radiation generating means 20 and the radiation detecting means 21 and transmitting / receiving a signal via a large pulley 16. . The slip ring mechanism 22 includes a disk-shaped slip ring 23 attached to the rotary casing 13, a power brush 24 and a signal brush 25 that are provided on the main frame 12 side and are in sliding contact with the slip ring 23.

A motor 30 is provided below the main frame 12, and a small pulley 31 is attached to the output shaft of the motor 30. The rotary casing 13 is driven to rotate by the belt 32 wound around the large pulley 25 and the small pulley 31.

A recess 40 is formed in the upper portion of the rear cover 18. Next, the operation of the above configuration will be described. When the motor 30 is driven, the rotational driving force of the motor 30 is transferred to the large pulley 25 via the small pulley 31 and the belt 32.
To the main frame 12
Rotate against.

On the other hand, power supply and signal transmission / reception to / from the radiation generating means 20 and the radiation detecting means 21 are performed via the slip ring mechanism 22. When the rotating casing 13 rotates, the radiation generating means 20 and the radiation detecting means 21 rotate around the object insertion hole 15, and the radiation generating means is applied to the object placed in the object insertion hole 15. Three
More radiation is emitted. The radiation that has passed through the subject is detected by the radiation detecting means 21. Radiation detecting means 21
Outputs an electric signal (projection data) according to the intensity of radiation. The radiation generating means 20 makes one rotation to obtain projection data from multiple directions on the subject 9 to form a tomographic image.

In the above structure, as shown in FIG. 3, the so-called head-first scan in which the cradle 51 is used to insert from the head of the subject 50 into the subject insertion hole 15 of the gantry, the rear cover 18 of the cover 14 is inserted. By forming the concave portion 40 in the upper portion, the range that shields the subject 50 from above is smaller than that in the case where the concave portion 40 is not provided, and the feeling of closure of the subject 50 can be reduced.

Further, as shown in FIG. 4, during the so-called foot first scan in which the foot of the subject 50 is inserted into the subject insertion hole 15 of the gantry, the knee of the subject is bent,
Further, when the gantry is tilted for scanning, the recess 40 is formed in the upper portion of the rear cover 18 of the cover, so that the tilt angle of the gantry is wider than in the conventional case, and the scanning can be performed in a wider tilt range.

Next, the second embodiment of the present invention will be described with reference to FIGS.
An example will be described. FIG. 5 is a front view for explaining an essential part of the second embodiment of the present invention, and FIG. 6 is a sectional view taken along line CC in FIG.

The difference between this embodiment and the first embodiment is the position of the brush of the slip ring mechanism 22 and the recess formed in the rear cover, and the other portions are the same as those in the first embodiment. Only the same parts will be described, and the same parts will be denoted by the same reference numerals and the description thereof will be omitted.

The power supply brush 64 and the signal brush 65 of this embodiment are provided under the gantry. 66 is the rear cover 1
8 is a concave portion 66 formed. According to the present embodiment, the power supply brush 64 and the signal brush 65 are arranged below the first embodiment, so that the recess 40 of the present embodiment is different from the recess 40 of the first embodiment in the cradle. It is possible to widen the side surface of the subject to be examined, so that the subject does not feel closed and the tilting range of the gantry is wider than in the first embodiment.

The present invention is not limited to the above embodiment. Although the recess is formed in the rear cover 18 in the above embodiment, the recess 6 is also formed in the front cover 17 as shown in FIG.
7 may be formed. By doing so, the subject is not given a sense of closure and the tilting range of the gantry is further expanded.

[0031]

As described above, according to the present invention, since the concave portion is formed in the upper part of the surface where the opening of the subject insertion hole is formed, the range that obstructs the upper visual field of the subject is reduced, Does not give the sample a sense of closure. Moreover, since the concave portion is provided,
The gantry tilt range is also expanded.

The main cover, the front cover, and the rear cover are composed of three covers, and the front cover and the rear cover are detachable, which facilitates the inspection and maintenance of the equipment inside the cover. By providing the slip ring on the rear cover side and forming the concave portion on this rear cover, the concave portion can be formed, which widens the upward field of view of the subject during head-first scanning and increases the tilting range of the gantry during foot-first scanning. Can be expanded.

By arranging the brush of the slip ring in the lower part of the gantry, it is possible to form a concave portion in a wider range, further, the object is not given a feeling of being closed, and the tilting range of the gantry is further widened.

[Brief description of drawings]

FIG. 1 is a front view illustrating a main part of a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line BB in FIG.

3 is a configuration diagram at the time of head fast scan in FIG. 1. FIG.

FIG. 4 is a configuration diagram at the time of a foot first scan in FIG.

FIG. 5 is a front view illustrating a main part of a second embodiment of the present invention.

6 is a cross-sectional view taken along the line CC of FIG.

FIG. 7 is a configuration diagram of another embodiment.

FIG. 8 is a front cross-sectional configuration diagram of a conventional gantry.

9 is a sectional view taken along the line AA in FIG.

FIG. 10 is a diagram showing a head first scan which is one mode during an inspection with the gantry shown in FIG.

FIG. 11 is a diagram showing a foot-first scan which is one mode at the time of inspection in the gantry shown in FIG.

[Explanation of symbols]

14 cover 15 Subject insertion hole 20 Radiation generating means 21 Radiation detection means 22 Slip ring mechanism 40 recess

Claims (3)

(57) [Claims] 1. A cover having a subject insertion hole formed therein, the cover having a front cover on a side on which a subject placed on a cradle is inserted and a rear cover opposite to the front cover. A radiation generating unit that is provided in the cover, rotates around the subject insertion hole, and emits radiation toward the subject insertion hole; and the radiation generation unit and the subject insertion hole in the cover. In a gantry comprising: a radiation detecting unit, which is arranged so as to face each other, rotates around the subject insertion hole while maintaining a positional relationship with the radiation generating unit, and detects the radiation; To widen the upper field of view of the subject when the head of the subject lying facing is located in the subject insertion hole, on the upper surface of the rear cover,
A gantry, characterized in that a recess is formed in the direction of the inside of the cover. 2. The gantry according to claim 1, wherein a slip ring mechanism using a disk-shaped slip ring for supplying and receiving signals to and from the radiation generating means and the radiation detecting means is provided in the cover. The cover is a main cover attached to a main frame, a front cover is detachably attached to the main frame, and a front cover having an opening for the subject insertion hole is formed, and the cover is detachably attached to the main frame, A gantry, comprising: a rear cover having an opening for the subject insertion hole, wherein the slip ring is provided on the rear cover side. 3. The gantry according to claim 1 or 2, wherein the brush of the slip ring is arranged below the gantry.