JPH08336521A - X-ray ct system - Google Patents

Abstract

PURPOSE: To easily perform maintenance on a power supply means and to improve reliability for the whole system by providing the power supply means with a non-contact feed means in an X-ray CT system equipped with a means to supply the power from a power source to an X-ray tube side in a scanner rotating part rotating successively. CONSTITUTION: An electromagnetic induction supply means 19 formed by combining a first coil 20a connected to the output side of an inverter 2 and arranged at the fixed frame of a scanner and divided into plural coils, and a second coil 20b arranged confronting with the first coil 20a and connected to the input side of a high voltage transformer 3 and divided into plural coils is installed as the means which supplies the power from the power source 1 disposed at the scanner rotating part 8 to the X-ray tube 5 side. In this way, a required power is supplied in non-contact fashion by an electromagnetic induction function, and a power supply part is prevented from wearing or corroding, and the maintenance of the power supply means is facilitated, and also, the reliability for the whole system is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to an X-ray CT apparatus that irradiates a ray, detects a transmitted X-ray image, reconstructs a tomographic image, and displays it as an image, and particularly supplies electric power from a power source to a X-ray tube side to a continuously rotating scanner rotating unit. The present invention relates to an X-ray CT apparatus which is provided with means and can facilitate maintenance and inspection of the power supply means and improve reliability.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 7, an X-ray CT apparatus of this type has a power source 1 for generating a DC voltage, an inverter 2 for converting the DC voltage from the power source 1 into an AC voltage, and an inverter 2 for this. High-voltage transformer 3 for boosting the AC voltage from the high-voltage transformer 3, a high-voltage rectifier 4 for rectifying the output voltage of the high-voltage transformer 3, and an X-ray that is supplied with the DC voltage from the high-voltage rectifier 4 and radiates X-rays. The tube 5 further has an X-ray detector 7 for detecting the transmitted X-ray dose distribution in which the X-rays emitted from the X-ray tube 5 pass through the subject 6 and amplifying the detection signal thereof. Subject 6 with line detector 7 facing it
An image processing apparatus 9 for processing a scanner rotation unit 8 including a rotation frame 8a that rotates around the axis and an output signal from an X-ray detection unit 7 mounted on the rotation frame 8a to reconstruct a tomographic image of a diagnostic region. And an image display device 10 for displaying a tomographic image by inputting an output signal from the image processing device 9, and means for supplying electric power from the power source 1 to the X-ray tube 5 and an image from the X-ray detection unit 7. As a means for sending a detection signal to the processing device 9, a plurality of sets of slip rings 11 provided between a rotary frame 8a of the scanner rotary unit 8 and a fixed frame (not shown) of the scanner.
a to 11c and brushes 12a to 12c are used in combination as a transmission means. In addition, in FIG.
The power supply 1 includes a commercial AC power supply 13, a converter 14 that converts the voltage of the AC power supply 13 into a DC voltage, and a capacitor 15 that smoothes the output voltage of the converter 14. Further, the X-ray detection unit 7 includes a detector 16 that detects a transmitted X-ray dose distribution transmitted through the subject 6, and the detector 16
And a preamplifier 17 that amplifies the detection signal from.
Further, reference numeral 18 is a resonance capacitor for causing the output voltage of the inverter 2 to resonate with the leakage inductance of the high voltage transformer 3 to obtain sufficient electric power.

A plurality of sets of slip rings 11a to 11c and brushes 12a to 12 provided on the scanner rotating unit 8 are provided.
The transmission means in combination with c is for continuously rotating the X-ray tube 5 and the X-ray detection unit 7 in one direction at high speed so that a plurality of tomographic images can be measured in a short time. The first and second slip rings 11a and 11b and the first and second brushes 12a and 12b send electric power for generating X-rays from the power source 1 from the power source 1 to the high voltage transformer 3, and the third slip ring. A detection signal from the X-ray detection unit 7 is sent to the image processing apparatus 9 by the 11c and the third brush 12c. The specific structure of the scanner rotating unit 8 is shown in FIG. The rotary frame 8a has a rotary plate 8b in the center of which an opening 19 for inserting a subject is formed, and a high voltage transformer 3, a high voltage rectifier 4, and an X-ray tube 5 are provided on one side surface of the rotary plate 20. The X-ray detector 7 is mounted, and a plurality of slip rings 1 are provided around a body 8c concentric with the rotary plate 8b.
1a to 11c are wound in parallel, and a plurality of brushes 12a to 12c provided on a fixed frame portion (not shown) that supports the rotary frame 8a are slidably contacted to these slip rings 11a to 11c, respectively. Was there.

[0004]

However, in such a conventional X-ray CT apparatus, as shown in FIG. 8, the scanner rotating section 8 supplies the X-ray generating power from the power source 1. First and second slip rings 11a, 11
Since b and the first and second brushes 12a and 12b supply electric power by mechanical sliding contact, a large current flows between the slip rings 11a and 11b and the brushes 12a and 12b. The contact portion was subject to wear and corrosion. That is, the high voltage transformer 3 mounted on the rotating frame 8a generates a high voltage of hundreds of tens of kV on the output side, and a sufficient insulation distance is provided inside for insulation from the input side. Therefore, for this reason, several μH
There is a leakage inductance of several tens of μH. The current flowing through the first and second slip rings 11a and 11b and the first and second brushes 12a and 12b is
The maximum is about 400A. In this state, when the rotary frame 8a rotates, the slip rings 11a, 11b
If a small gap is generated between the brush and the brushes 12a and 12b provided on the fixed frame, the current tends to continue flowing due to the influence of the leakage inductance, and an arc is generated in the gap to locally raise the temperature. there were. Then, due to this high temperature, the slip rings 11a and 11b and the brush 12 are
The a and 12b were sometimes worn or corroded. Therefore, conventionally, maintenance and inspection such as polishing of the slip rings 11a and 11b and replacement of the brushes 12a and 12b have to be performed regularly, for example, every one to two months, which requires a lot of labor and maintenance. It was costly. If the above maintenance is not performed properly, X-ray CT
The reliability of the entire device may decrease.

Therefore, the present invention addresses such problems and facilitates maintenance and inspection of the power supply means for supplying power from the power supply to the X-ray tube side in the continuous rotation type X-ray CT apparatus. X-ray CT that can improve reliability
It is intended to provide a device.

[0006]

In order to achieve the above object, the present invention provides a power source for generating a DC voltage, an inverter for converting the DC voltage from the power source into an AC voltage, and an AC voltage from the inverter. High-voltage transformer for boosting, rectifier for rectifying output voltage of the high-voltage transformer, X-ray tube for radiating X-rays by being supplied with DC voltage from the rectifier, and object for radiating from the X-ray tube An X-ray detection unit that detects the transmitted X-ray dose distribution and that amplifies the detection signal, and a scanner rotation unit that makes the X-ray tube and the X-ray detection unit face each other and rotate around the subject. An image processing apparatus for processing an output signal from an X-ray detection section of the scanner rotating section to reconstruct a tomographic image of a diagnostic region, and an image display for displaying the tomographic image by inputting an output signal from the image processing apparatus. The device and the scanner rotation part An X-ray CT apparatus comprising means for supplying electric power from a source to the X-ray tube side, wherein the electric power supply means is connected to an output side of the inverter and is arranged in a fixed frame of the scanner. And a second winding that is connected to the input side of the high-voltage transformer and that is arranged on the rotating frame of the scanner rotating unit so as to face the first winding. The main magnetic flux generated by the first winding is guided to the main magnetic conductor formed by the second winding.

Further, according to the present invention, a first iron core for accommodating the first winding and a second winding are accommodated between the fixed frame of the scanner and the rotary frame of the scanner rotating portion. It is arranged so as to face the second iron core.

Further, according to the present invention, the first winding,
At least one of the second winding, the first iron core, and the second iron core is divided into a plurality of parts.

Further, according to the present invention, a plurality of divided windings of the first winding or the second winding is connected in parallel.

Further, in the present invention, a plurality of divided windings of the first winding or the second winding is connected in series.

[0011]

In the X-ray CT apparatus constructed as described above, the first winding and the second winding are combined as power supply means for supplying power from the power supply to the X-ray tube side in the scanner rotating unit. By providing the electromagnetic induction power transmission means, it is possible to operate in a non-contact manner so as to supply the required electric power by the electromagnetic induction action, not by the conventional mechanical sliding contact between the slip ring and the brush. As a result, it is possible to prevent abrasion and corrosion of the conventional power supply portion, facilitate maintenance and inspection of the power supply means, and improve reliability.

Next, in the present invention, the magnetic circuit is constructed so that the main magnetic flux generated by the first winding is guided to the main magnetic path formed by the second winding.
The magnetic flux generated in the first winding is directly guided to the second winding through the first iron core and the second iron core to efficiently induce an induced current in the second winding. be able to.

Further, according to the present invention, since the winding and the iron core are divided into a plurality of pieces, the iron core can be divided and manufactured, so that the iron core can be individually processed and the first core is also assembled. Since it is possible to adjust the gap between the iron core and the second iron core as narrow as possible, it is possible to form a magnetic circuit having a small magnetic resistance as the entire electromagnetic induction power transmission means.

In the present invention, the first winding or the second winding is divided into a plurality of pieces and the divided windings are connected in parallel. In this case, the windings are connected in parallel. By doing so, the leakage inductance can be reduced, and as a result, the frequency of the device can be increased and the high-voltage transformer can be downsized.

In the present invention, the second winding is divided into a plurality of parts and connected in series. In this case, the output voltage of the second winding is multiplied in accordance with the number of divisions of the winding. Therefore, it becomes a high voltage. As a result, the input voltage of the high-voltage transformer in the next stage becomes high, so that the turns ratio of the high-voltage transformer can be reduced accordingly, and the high-voltage transformer can be downsized.

[0016]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. FIG. 1 is a block diagram of the overall configuration showing an embodiment of an X-ray CT apparatus according to the present invention. This X-ray CT
The device emits X-rays to the diagnostic site of the subject and transmits the X-ray
The dose distribution is detected, the tomographic image is reconstructed and displayed as an image. As shown in FIG. 1, the power source 1, the inverter 2, the high voltage transformer 3, the high voltage rectifier 4, and the X It has an X-ray tube 5, an X-ray detection unit 7, an image processing device 9, and an image display device 10, and electromagnetic induction is applied to the scanner rotation unit 8 as a means for supplying electric power from the power source 1 to the X-ray tube 5 side. The transmission means 19 is provided, and as a means for sending a detection signal from the X-ray detection section 7 to the image processing apparatus 9, transmission means using a combination of a slip ring 11c and a brush 12c provided in the scanner rotation section 8 is used.

The power supply 1 generates a DC voltage. In FIG. 1, a commercial AC power supply 13 and a converter 1 for converting the voltage of the AC power supply 13 into a desired DC voltage.
4 and a capacitor 15 for smoothing the output voltage of the converter 14. The power source 1 is not limited to the above configuration as long as it can generate a DC voltage, and may be a battery, for example. The inverter 2 is
The DC voltage output from the power supply 1 is converted into high-frequency AC. The high-voltage transformer 3 boosts the AC voltage output from the inverter 2. Further, the high voltage rectifier 4 converts (rectifies) the output voltage of the high voltage transformer 3 into a DC high voltage. The power source 1, the inverter 2, the high-voltage transformer 3, and the high-voltage rectifier 4 constitute an X-ray high-voltage device.

The X-ray tube 5 is supplied with the DC high voltage output from the high-voltage rectifier 4 and emits X-rays toward the subject 6. Then, the X-rays that have passed through the subject 6 enter the X-ray detector 7. This X-ray detector 7
Is for detecting the transmitted X-ray dose distribution which is emitted from the X-ray tube 5 and transmitted through the subject 6, and amplifies the detection signal, and a detector 16 for detecting the transmitted X-ray dose distribution,
Preamplifier 1 for amplifying the detection signal from the detector 16
7 and 7.

Further, the image processing device 9 inputs and processes the output signal from the X-ray detecting section 7 to reconstruct a tomographic image of the diagnostic region of the subject 6. Further, the image display device 10 receives the output signal from the image processing device 9 and displays a tomographic image, and is composed of, for example, a television monitor. In FIG. 1, reference numeral 18 is a resonance capacitor for causing the output voltage of the inverter 2 to resonate with the leakage inductance of the high voltage transformer 3 to obtain sufficient electric power.

The high-voltage transformer 3, the high-voltage rectifier 4, the X-ray tube 5, and the X-ray detection unit 7 are connected to the scanner rotation unit 8.
The X-ray tube 5 and the X-ray detection unit 7 are mounted on the rotary frame 8a of the above and rotate around the subject 6 while facing each other with the subject 6 interposed therebetween. The rotating frame 8
As shown in FIG. 8, a has a rotary plate 8b in which an opening 19 for inserting a subject is formed in the central portion.
The high-voltage transformer 3, the high-voltage rectifier 4, the X-ray tube 5, and the X-ray detector 7 are mounted on one side of b, and a slip ring for transmitting a detection signal is provided around the body 8c of the rotary frame 8a. 11c
Is provided. A brush 12c is provided on a fixed frame (not shown) of the scanner so as to face the slip ring 11c.

Here, in the present invention, as shown in FIG. 1, as a means for supplying electric power from the power source 1 to the X-ray tube 5 side, the fixed frame portion of the scanner and the rotary frame 8 of the scanner rotary unit 8 are provided.
An electromagnetic induction power transmission means 19 is provided between the electromagnetic induction transmission means 19 and a. The electromagnetic induction power transmission means 19 supplies required power in a non-contact state by an electromagnetic induction action, one end of which is connected to the output side of the inverter 2 and the other end of which is connected to the input side of the high-voltage transformer 3. ing. This electromagnetic induction power transmission means 19 has two
It is a combination of two windings. First winding 20a
Is connected to the output side of the inverter 2 and is arranged in the fixed frame of the scanner. The second winding 20b is connected to the input side of the high voltage transformer 3 and is arranged on the rotating frame 8a so as to face the first winding 20a.

Next, a specific structure of the electromagnetic induction power transmission means 19 will be described with reference to FIG. FIG. 2A is a sectional view showing the positional relationship between the fixed frame 21 and the rotary frame 22 of the scanner. FIG. 2B is an enlarged perspective view showing a portion of the electromagnetic induction power transmission means 19 surrounded by a broken line in FIG. 2A. First, the rotary frame 22 is a bearing 23 provided inside the fixed frame 21 with a certain distance in the axial direction.
It is rotatably held by a and 23b. A first iron core 24a and a second iron core 24b are arranged facing each other on the inner peripheral surface of the fixed frame 21 and the outer peripheral surface of the rotary frame 22. Each iron core may be integrated, or may be divided into a plurality of pieces. Further, a combination in which one iron core is integrated and the other iron core is divided may be used. First iron core 2
The first winding 20a connected to the output side of the inverter 2 is fitted and fixed in the groove provided in 4a. Second iron core 2
Similarly, the second winding 20b connected to the input side of the high-voltage transformer 3 is fitted and fixed in the groove provided in 4b. At this time, both the first winding 20a and the second winding 20a are divided into small windings in accordance with the division of the first iron core 24a and the second iron core 24b.

The divided small windings are tangentially connected in parallel. Then, the respective small windings are arranged at appropriate intervals on the circumference of the fixed frame 22 or the rotary frame 22 of the scanner (see FIG. 5A). In this state, FIG. 2 (b)
As shown in FIG. 5, each first winding 20a has an arc shape of the same size as the number of divided windings arranged in the fixed frame 21 between the bearings 23a and 23b, and has a cross section. The E-shaped iron core is wound for several turns (FIG. 2B shows the case where the number of turns is 1.), and the first winding 20a is wound.
The magnetic flux generated in the second winding 20b passes through the iron cores.
Try to link to. On the other hand, the second winding 20b is the same as the first winding 20a between the bearings 24a and 24b.
A number of turns are wound on an iron core having an E-shaped cross section in the shape of a circular arc of the same number and the same number as the number of windings divided in the rotating frame 22 facing each other. With such a structure, the first winding 20a and the second winding 20 facing each other
b and an arc-shaped first iron core 24a having an E-shaped cross section and a second iron core 24b having an arc-shaped and E-shaped cross section which face each other realize a mechanism such as an outer iron type transformer. The iron cores may be arranged with almost no space between them,
If the power conversion efficiency may be slightly lowered, a method of providing a certain interval may be adopted.

By constructing the electromagnetic induction power transmission means as described above, when the alternating current supplied from the inverter 2 in FIG. 1 flows through the first winding 20a, they face each other as shown in FIG. 2 (b). First winding 20a and second winding 2
0b, and a second iron core 24 having an arcuate shape and an E-shaped cross section, similarly to a first iron core 24a having an arcuate shape and an E-shaped cross section.
In a structure such as an outer-iron type transformer configured with b, magnetic flux φ is generated in the magnetic circuit. Then, a voltage is induced in the second winding 20b that is linked to the magnetic flux φ, and AC power can be supplied from the second winding 20b to the high-voltage transformer 3 shown in FIG.

FIG. 3 shows an essential part of the second embodiment of the present invention, and the display is similar to that of FIG. The electromagnetic induction power transmission means 19 in this embodiment follows the same principle as that of the first embodiment, except that the first winding 20a and the second winding 20b are opposed to each other, and the arc-shaped cross sections are opposite to each other. In a magnetic circuit composed of a U-shaped first iron core 24a and a second iron core 24b, a method of producing a magnetic flux flow similar to that of an inner iron type transformer is characterized. Also in this embodiment, the first iron core 24a and the second iron core 2 are
4b may be divided into a plurality of cases or a single case.

Next, the division of the winding and the iron core will be described with reference to FIG. FIG. 5A shows a case where the first winding 20a and the first iron core 24a are divided into a plurality of pieces, and in accordance with this, the second winding 20b and the second iron core 24b are also divided into a plurality of pieces. At this time, the divided windings are connected in parallel. In FIG. 5B, the first winding wire 20a and the first iron core 24a are divided into a plurality of pieces, and the second winding wire 20b and the second iron core 24b are united. In FIG. 5C, the first winding 20a and the first iron core 24a are divided into a plurality of pieces, the second winding 20b is a single piece, and the second iron core 24b is divided into a plurality of pieces. As described above, various variations can be considered for the division of the winding wire and the iron core, but what is important in the present invention is that the magnetic flux generated in the first winding wire 20a passes through the respective iron cores to the second magnetic flux. That is, it is configured to interlink with the winding wire 20b. Further, the method of using the E-shaped iron core is effective as a method of reducing the current (excitation current) for exciting the iron core, as compared with the case of using the U-shaped iron core.

If the iron cores are divided as in the structure of the first and second embodiments, the size of each iron core can be reduced and the dimensional accuracy in manufacturing can be improved. Furthermore, since the power conversion efficiency of electromagnetic induction is almost determined by how small the distance between the first iron core 24a and the second iron core 24b can be made, a mechanism (not shown) that can finely adjust the position of each iron core, etc. If the rotary unit is provided and the rotary unit is rotated at an optimum interval, the power conversion efficiency can be improved. Further, when the small windings of the first winding 20a or the second winding 20b are connected in parallel, it becomes possible to reduce the leakage inductance, and the inverter 2
It is also possible to cope with higher frequencies.

In the first and second embodiments described above, the case where the iron cores are provided on the inner peripheral side of the fixed frame 21 and the outer peripheral side of the rotary frame 22 has been described, but the present invention is not limited to this. ,
Grooves for fitting the windings are provided in the respective facing portions of the fixed frame 21 and the rotary frame 22, and the first windings 20 are provided in these grooves.
The a and the second winding 20b may be fitted. At this time, the fixed frame 21 and the rotary frame 22 can be configured as a magnetic circuit if they are made of a mild steel plate or the like.

FIG. 4 shows a third embodiment of the present invention. In this embodiment, the electromagnetic induction power transmission means 19 is
It is provided on the flange-shaped portions of the fixed frame 21 and the rotary frame 22. Although an enlarged view is shown in FIG. 4B, the structure is almost the same as that of the embodiment shown in FIG. 2 except that the cylindrical structure is changed to a disk structure. It is considered that the accuracy of the gap size between the iron cores is better in this embodiment than in the first and second embodiments. The other effects are the same as those of the first and second embodiments.

In the embodiment described above, the two bearings 23 are provided between the opposing iron cores 24a and 24b.
Rotating part 8 of scanner rotatably supported by a and 23b
Has a small gap that allows it to rotate smoothly. In order to make the leakage resistance of the magnetic flux φ generated in the magnetic circuit almost non-existent, reduce the magnetic resistance of the magnetic circuit, and ensure that the magnetic flux φ is linked to the second winding 20b, It is desirable to make the gap as small as possible. Therefore, even if the end surfaces of the two iron cores 24a and 24b are in contact with each other, the rotating operation of the rotating frame 22 is not hindered,
In addition, if there is no fear of wear, the above gap may not be formed.

Further, since the iron cores 24a and 24b are arranged on the circumference of the scanner fixed frame 21 or the rotary frame 22 of the scanner, the cross-sectional area of the iron core can be made relatively large so that the operating magnetic flux density is low, Loss is hardly a problem.
Therefore, the material of each iron core 24a, 24b is not limited to iron, and silicon steel plate, ferrite, other ferromagnetic material or paramagnetic material may be used, but it is not necessary to select a material with low loss. .

In the above description, the first winding 20a
Although the number of turns of the second winding 20b is the same as that of the second winding 20b, if the ratio of the number of turns is changed, the inverter 2 and the high voltage transformer 3
The degree of freedom in circuit design including can be increased. For example, if the second winding 20b is wound more than the first winding 20a, the voltage on the output side of the electromagnetic induction power transmission means 19 becomes higher than that on the input side, and the turn ratio of the high voltage transformer 3 is correspondingly increased. Can be made smaller. As a result, it is possible to reduce the size of the high voltage transformer 3 and reduce the leakage inductance or stray capacitance.

Besides, in the above embodiment, the divided windings are connected in parallel, but in some cases, they may be connected in series. For example, when the second winding 20b is connected in series, the effect that the turns ratio of the high-voltage transformer 3 can be designed to be small is produced, as in the case where the number of turns is changed as described above.

Further, in the above embodiment, the cross section of the iron core is U-shaped or E-shaped.
The magnetic flux generated in the first winding 20a is the first iron core 24a.
If the second winding 20b and the second winding 20b are linked to each other via the second iron core 24b, other shapes can be adopted regardless of the above-mentioned shape. For example, as shown in FIG. 6, the second iron core 24b is replaced with the first iron core 24a to reduce the leakage flux.
It is an effective means to have a shape that wraps around.
In addition, the first winding 20a and the second winding 20b have a Litz wire (Litz wire) in order to reduce eddy current loss generated in the winding.
Using e) is also effective for improving the power conversion efficiency.

Further, in FIG. 1, a capacitor 18 for resonance is connected to the output side of the inverter 2, but this capacitor 18 has a high frequency current due to the leakage inductance of the high voltage transformer 3. It is inserted for the purpose of improving that the high voltage transformer 3 does not flow sufficiently, and is not limited to the above, and the second winding 20b and the high voltage transformer 3 are not limited thereto.
It may be inserted between and, or may not be inserted if the above improvement is not required.

Further, in FIG. 1, the scanner rotating unit 8
The means for sending the detection signal from the X-ray detector 7 to the image processing device 9 is the slip ring 11c as in the conventional example shown in FIG.
Although the brush 12c and the brush 12c are used, the present invention is not limited to this, and the winding 20
A and 20b may be combined and transmitted by utilizing an electromagnetic induction effect, or light, radio waves or the like may be used.

[0037]

Since the present invention is constructed as described above,
By providing the electromagnetic induction power transmission means which is a combination of the first winding and the second winding as the power supply means for supplying the power from the power supply to the X-ray tube side in the scanner rotating unit Electric power can be supplied in a contactless manner by an electromagnetic induction action without relying on mechanical sliding contact between the slip ring and the brush. This eliminates the conventional problems of wear and corrosion of the power supply portion, which facilitates maintenance and inspection of the power supply means and improves the reliability of the entire apparatus.

[Brief description of drawings]

FIG. 1 is a block diagram of the overall configuration showing an embodiment of an X-ray CT apparatus according to the present invention.

FIG. 2 is a diagram showing a main part of a specific structure of electromagnetic induction power transmission means.

FIG. 3 is a diagram showing a main part of a second embodiment of the present invention.

FIG. 4 is a diagram showing a main part of a third embodiment of the present invention.

FIG. 5 is a diagram showing a first winding and a second winding of the electromagnetic induction power transmitting means that is a main part of the present invention, division of the first iron core and the second iron core, and combinations thereof.

FIG. 6 shows an example of a structure for reducing leakage flux in the present invention.

FIG. 7 is a block diagram of an overall configuration showing a conventional X-ray CT apparatus.

FIG. 8 is a perspective view showing a specific structure of a scanner rotating unit according to a conventional example.

[Explanation of symbols]

 1 Power Supply 2 Inverter 3 High Voltage Transformer 8 Scanner Rotating Part 8a, 22 Rotating Frame of Scanner Rotating Part 11a to 11c Slip Ring 12a to 12c Brush 19 Electromagnetic Induction Transmission Means 20a First Winding 20b Second Winding 21 Scanner Fixed frame 24a First iron core 24b Second iron core

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Noriyuki Uchiyama 1-1-1 Kokubun-cho, Hitachi-shi, Ibaraki Hitachi Kokubun Plant, Hitachi Research Institute, Ltd.

Claims (5)

[Claims] 1. A power supply for generating a DC voltage, an inverter for converting a DC voltage from the power supply into an AC, a high voltage transformer for boosting the AC voltage from the inverter, and an output voltage of the high voltage transformer. A rectifier that rectifies the X-ray, an X-ray tube that is supplied with a DC voltage from the rectifier and emits X-rays, and a transmitted X-ray dose distribution that is emitted from the X-ray tube and that has passed through the subject, and that detection signal is amplified. An X-ray detection unit, a scanner rotation unit that makes the X-ray tube and the X-ray detection unit face each other and rotate around the subject, and an output signal from the X-ray detection unit of the scanner rotation unit is processed. An image processing device for reconstructing a tomographic image of a diagnostic region, an image display device for inputting an output signal from the image processing device to display a tomographic image, and the scanner rotating unit from a power source to the X-ray tube side. X-ray comprising means for supplying electric power In the T device, the power supply means is connected to an output side of the inverter and is connected to a first winding arranged in a fixed frame of the scanner and an input side of the high voltage transformer, and A combination of a second winding arranged opposite to the first winding on a rotary frame of a scanner rotating unit, and a main magnetic flux generated by the first winding is the second winding. X-ray C characterized by being guided to a main magnetic conductor formed by
T device. 2. The X-ray CT apparatus according to claim 1, wherein a first iron core that accommodates the first winding is provided between a fixed frame of the scanner and a rotary frame of the scanner rotating unit, and An X-ray CT apparatus characterized in that it is arranged to face a second iron core that houses a second winding. 3. The X-ray CT apparatus according to claim 1, wherein at least one of the first winding, the second winding, the first iron core, and the second iron core is divided into a plurality of pieces. X-ray CT device characterized by being arranged as follows. 4. The X-ray CT apparatus according to claim 3, wherein a plurality of windings of the first winding or the second winding are connected in parallel. 5. The X-ray CT apparatus according to claim 3, wherein a plurality of windings of the first winding or the second winding are connected in series.