JPS60242348A - Industrial ct scanner - Google Patents

Abstract

PURPOSE:To measure an annular object of inspection efficiently by providing a driving system which makes a traverse scan on the object relatively to a radiation generator and a detector, a system which rotates the object of inspection around one point of its sectional inspection part, and a system which inverts the object of inspection. CONSTITUTION:A data detection system 20 consists of a support 21 with a U- shaped projecting arm 21a, generator and detector side collimators 22 and 23, a multichannel radiation detector 24, and a radiation generator 26, and a fan- shaped radiant beam 28 is projected upon the annular object 27 of inspection by the generator 26. A traverse driving system 30 consists of a traverse driving part 31, a traverse frame which is engaged with a screw body 33 to move the object 27 of inspection to right and left, etc. Further, the rotation driving part 40 consists of a rotation driving part 41 which rotates the object 27 of inspection by a specific angle as shown by an arrow (a) and a rotary frame. Then, the inversion driving system 40 consists of an inversion driving part 51 which rotates the object 27 of inspection in two directions, inverting frame 52, and fixation body 54 for the object of inspection.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an industrial CT scanner that captures tomographic images of annular objects with high precision.

[Technical background of the invention]

Conventionally, for example, in a medical CT scanner called the second generation, as shown in FIG. A traverse frame 2 is attached, and an X-ray generator 3 and an X-ray detector 4 are provided on straight sides of the frame 2 so as to face each other with a subject 5 in between. The subject 5 is placed on a table 6 erected on the floor, and is placed between the two devices 3 and 4. 7,
8 is a collimator, and 9 is an X-ray generator fixing plate.

In the above configuration, by applying a traverse control signal from the outside to drive the traverse mechanism section 10, the X-ray generator 3 and the X-ray detector 4 are traversed.
A fan-shaped X-ray beam 11 is irradiated from the X-ray generator 3 while integrally performing traverse scanning at a predetermined distance along the frame 2, and the X-ray transmission data transmitted from the subject 5 is measured by the X-ray transmission data. It is detected by the detector 4.

When the traverse set meal in one direction is completed as described above, a rotation control signal is applied from the outside to drive the rotation mechanism section 12, thereby rotating the rotation frame 1 by a predetermined angle. After 10 rotations of the rotating frame, traverse scanning is performed in the opposite direction, and X-ray transmission data from the subject 5 is similarly detected by the X-ray detector 4. The above operations are repeated until the rotating frame 1 rotates 180 degrees or 360 degrees. Although not shown, the data detected by the X-ray detector 4 is processed by a conventionally well-known computer having data acquisition means, image reconstruction processing means, CPU, and other necessary functions, and a tomographic image of the subject 5 is obtained. is created. 13 is a fixed frame.

[Problems with background technology]

By the way, when obtaining a tomographic image of, for example, the annular object 5 as shown in FIG. Therefore, when this is subjected to image reconstruction processing by the image reconstruction processing circuit, the actual solid cross section 5a is compared with the entire cross sectional image.

The image reconstruction processing portion 5b is very small, and the resolution of the images of the solid cross-section portions 5a and 5b is correspondingly low. Furthermore, when inspecting a force-like object 5 such as an automobile tire, it is inevitable that the traverse frame 2 and rotary frame 1 that cover the tire from the outside are large (and thus the entire CT scanner will be large). Also, both sides 3 and 4
There is a problem that the distance between them becomes considerably long and the measurement efficiency decreases.

[Purpose of the invention]

The present invention has been made with attention to the above points, and an object of the present invention is to provide an industrial CT scanner that can efficiently measure data on an annular object and obtain high-resolution tomographic images.

[Summary of the invention]

The present invention fixes a radiation generator and a radiation detector facing each other, and uses a traverse drive system, a rotation drive system, and a reversal drive system to freely set the position of a cross-sectional inspection part that is a part of an annular object. This is an industrial CT scanner that acquires data for creating tomographic images.

[Embodiments of the invention]

Next, an embodiment of the present invention will be described with reference to FIGS. 3 to 6. Figures 3 to 5 show the mechanical configuration of the industrial CT scanner, with Figure 3 being a view from above, Figure 4 being a view of Figure 3 seen from the front, and Figure 5 being a view from the front. Third
FIG. 6, seen from the left side, is a diagram showing the electrical configuration of the industrial CT scanner. The mechanical configuration shown in FIGS. 3 to 5 includes a data detection system 201, a traverse drive system 3, and
0, a rotational drive system 40 and a reversal drive system 50.

The data detection system 20 is installed on the floor and has a support 21 having a U-shaped arm 21& integrally or separately protruding from the upper side to one side. A generator-side collimator 22 is attached to the arm, and a detector-side collimator 23 and a multi-channel radiation detector 24 are attached to the other end of the arm. Furthermore, a radiation generator 26 is arranged at one end of the arm 21a with a required distance from the generator-side collimator 21 with or without the fixing plate 25 interposed therebetween. Note that 27 is an annular object such as a car tire, and 28 is a fan-shaped radiation beam.

Next, the traverse drive system 30 includes a traverse drive section 31
, a pair of bearings installed with a predetermined distance, ? 2.3
2, a screw body 33 rotatably supported between the pair of bearings 32, 32 and rotated by the rotational driving force of the traverse drive unit 3; a screw body 33 that is engaged with the screw body 33;
30 A pair of traverse frames 34 that move the subject 27 left and right (in the direction of the arrow in the figure) in the rotational direction, and a pair of traverse frames s4f that are laid parallel to and at a predetermined distance from the screw body 33 and guide the traverse frames s4f in a predetermined direction. It is composed of traverse rails 35, 35, etc.

The rotational drive unit 40 rotates the other end of the object 27 by a predetermined angle in the direction of the arrow in the figure around the point where the cross-sectional inspection unit is located, for example, the center point O. 41, a horizontal rotating frame section 421L rotatably provided on the traverse frame 34, and a horizontal rotating frame section 421L that is erected at one end of the frame section 42a so as to be orthogonal to the surface of the frame section 42a, which will be described later. Upright rotating frame section 4 that grips the reversing frame
2b.

The reversing drive system 50 rotates and reverses the subject 27 in the direction of the two arrows shown in the figure. Specifically, the reversing drive system 50 includes a reversing drive section 51 installed on the rotating frame 42 and an upright rotating frame section 42b. A pair of lower pieces 5 that are rotatably provided and protrude in parallel from the lower side and the upper side of the upright rotating frame section 42b, respectively, so as to sandwich the subject 22 therebetween.
2a and an upper piece 52b, and a reversing frame 52 that inverts the subject 27 by applying a rotational driving force from the reversing drive unit 51 by an endless strip or a gear 53, and the lower piece 52a and the upper piece 52b. The test object fixing body 54 is provided inside the test object fixing body 54 to seal the movement of the test object 22.

Next, FIG. 6 is a block diagram showing the electrical configuration of an industrial CT scanner. In the figure, reference numeral 61 denotes a console, which has the function of giving necessary commands to a central processing unit (hereinafter referred to as CPU) 62 that collectively controls each section. This CPU 62 is the console 6
When a command is received from 1, necessary control signals are given to the mechanism control section 63 and the radiation control section 64 based on a predetermined program. The mechanism control unit 63 is
A signal for driving the traverse drive section 31, rotation drive section 41, and reversal drive section 51 is output. The radiation control unit 64 has a function of applying a high voltage to the radiation generator 26 in response to a control signal from the CPU 62 to irradiate the radiation generator 26 with radiation. A data acquisition unit 65 digitizes the radiation absorption data from the radiation detector 24 and sends it to the CPU 62 . A memory 66 and an image reconstruction processing circuit 67 are connected to this CPU 62. 68 is a CRT display.

Next, the operation of the industrial CT scanner configured as above will be explained. That is, the OCT scanner does not inspect the annular object 27 according to the trajectory shown in FIG. 2, but instead follows the trajectory indicated by the dotted line H as shown in FIG. This will be explained according to Figure 8. When a command to start scanning is issued from the console 61, in response to this command, the CPU 62 supplies control signals to the mechanism control section 63 and the radiation control section 64 according to a predetermined zologram. Here, the mechanism control unit 63 may be configured, for example, in FIG.
From the state of a), a traverse drive control signal is supplied to the traverse drive unit 31 to traverse the traverse frame 24 in the right direction in FIG. 3 and move the radiation generator 26 to the position as shown in FIG. 8(b). After the horizontal radiation beam 28 is irradiated onto the subject 27 and the radiation transmission data from the subject 27 is detected by the radiation detector 24, this detected data is sent to the CPU via the data collection unit 65.
62, and is created as image data by an image reconstruction processing circuit 67. Hereinafter, the data collection means and the image data creation means are the same as those described above, and since the data creation means are conventionally known, a detailed explanation will be omitted.

Thus, the mechanism control section 63 supplies a rotation drive signal to the rotation drive section 41 from the state shown in FIG. 8(b). Then,
Traverse and
Since the horizontal rotating frame part 42a of the rotating frame 42 on the frame 24 rotates around point 0 shown in FIG. 3, the upright rotating frame part 42b stands upright from the outside of the horizontal rotating frame part 42th. grips and rotates the reversing frame 52.

As a result, since the inversion frame 52 holds the subject 27, the subject 27 moves from the dotted line to the solid line as shown in FIG. 8(C).

Subsequently, the mechanism control section 63 provides a traverse drive control signal to the traverse drive section 31. As a result, the traverse drive unit 31 rotates the screw body 33 via the bearing 32° 32, and moves the traverse frame 34 to the left in the opposite direction to that described above. FIG. 8(d) shows such a state.

Thereafter, the mechanism control section 63 sets the subject 27 in the same direction as the traverse direction by alternately and repeatedly controlling the rotation drive section 41 and the traverse drive section 31 as shown in FIG. With this setting, the subject 27 is
If the position is as indicated by the dotted line, the traverse drive unit 31
The subject 27 is pulled out to the outside of the U-shaped arm 21a of the position bar support 2 shown in solid line.

Next, from the state shown in FIG. 8(f), the mechanism control unit 63 supplies a reversal drive signal to the reversal drive unit 5, whereby the subject 27 is reversed 180 degrees and moves from the solid line area to the dotted line area. do. As a rule, the subject 27 moves from an upright state to a horizontal state. Furthermore, 18 as shown in Figure 8 (11)
When the object 27 is reversed by 0 degrees, the object 27 moves to the dotted line portion as shown in FIG. 8(i). As a result, the subject 27 is completely inverted and stands upside down.

Thereafter, the mechanism control unit 63 supplies a traverse drive control signal to the traverse drive unit 31 to move the traverse frame 24 to the right in the direction of the arrow in the figure, thereby moving the subject 27 to the solid line area in the figure. . Next, when a rotational drive signal is supplied from the mechanism control unit 63 to the rotational drive unit 41,
As in the above explanation, the outside of the subject 27 rotates by a predetermined angle about point 0. If the traverse drive section 3 and the rotation drive section 4 are alternately drive-controlled in FIG. 8(k), the subject 27 is set in the dotted line area in FIG. 8(c). Furthermore, when the mechanism control unit 63 controls the 9) laparth drive unit 3, the subject 27 moves to the left,
Return to the position shown in Figure 8 (R). That is, through the series of drive controls described above, the inspection is performed along the trajectory along the dotted line in FIG. 7, and data necessary for image reconstruction is obtained.

Therefore, according to the configuration of the embodiment as described above, it is possible to control the posture of the subject 27 by effectively combining the traverse drive system 30° rotation drive system 40 and the reversal drive system 5o with the U-shaped arm 21h. Even if the test object 27 is annular, partial cross-sectional data of the test object 27 can be obtained by following the dotted line locus in FIG. In other words, it is possible to create image data using the entire reconstructed image area of only a partial cross section of the subject 27).
The resolution of tomographic images can be significantly improved. Even the object 27 to be inspected, such as a tire, can be inspected by making the entire CT scanner smaller, the distance between the radiation generator 26 and the radiation detector 24 can be shortened, and the measurement efficiency can be increased. Also, since the amphipod 26° 24 and the collimators 22 and 23 are fixed to the U-shaped arm 21a, 1. It is easy to achieve positional accuracy with respect to the radiation beam 28.

Note that the present invention is not limited to the above embodiments.

The radiation may be not only β-rays and γ-rays but also X-rays and other radiations. Although the subject fixing bodies 54 are provided at the lower and upper portions of the inversion frame 52, the subject fixing bodies 54 may be configured to be movable to any position depending on the size of the subject 27. In addition, the present invention is not limited to the above embodiments, and can be implemented in various modifications.

〔Effect of the invention〕

As described in detail above, according to the present invention, even if the object is annular, 90-degree angle data can be acquired by normal scanning means,
For the remaining 90 degrees, the object is inverted and cross-sectional data is acquired from the back side of the object, making it much smaller than previous models and shortening the distance between the transducers to efficiently acquire data. It is possible to provide an industrial CT scanner that can create highly accurate reconstructed images.

[Brief explanation of the drawing]

Fig. 1 is a front view of a conventional medical CT scanner, Fig. 2 is a diagram showing an inspection trajectory when inspecting a car tire using the OCT scanner shown in Fig. 1, and Figs. FIG. 3 is a plan view of the mechanical configuration, FIG. 4 is a front view thereof, and FIG. 5 is a left side view thereof. FIG. 6 is a block diagram showing the electrical configuration, FIG. 7 is a diagram showing the inspection trajectory of the CT scanner of the present invention, and FIG. 8 is a diagram showing the inspection procedure of the industrial CT scanner according to the present invention. 20... Data detection system, 24... Radiation detector, 2
6... Radiation generator, 27... Subject, 30...
Traverse drive system, 31... Traverse drive unit, 33
...Screw body, 34...Traverse frame, 40
...Rotary drive system...41...Rotary drive section, 42...
- Rotating frame, 50... Reversing drive system, 51... Reversing drive unit, 52... Inverting frame, 54... Subject fixing body, 62... CPU, 63... Mechanism control unit, 6
4... Radiation control section, 65... Data collection section, 67
...Image reconstruction processing circuit. Applicant's representative Patent attorney Takehiko Suzue Figure 1 Figure 2\, /' Figure 4 Figure 7 Figure 8 (a) (b) (c)

Claims (1)

[Claims] (1) A radiation generator and a radiation detector are disposed facing each other, a subject is placed between these two devices, and radiation transmission data obtained by irradiating the subject with radiation is obtained. A CT scanner that obtains tomographic image data of a subject through image reconstruction processing includes a traverse drive system that traverse-scans the subject relative to both devices, and a cross section that is blurred on the traverse frame of this traverse drive system. A rotational drive system, in which a horizontal rotation frame part, which is one side of the L-shaped rotation frame, is rotatably provided, and rotates the subject to be rotated about a point on the cross-sectional inspection part of the subject; A reversing drive system is provided rotatably on one side of the upright rotating frame part, which is the other side of the frame, to hold the subject and drive the subject in reverse, even if the subject is annular. Industrial C characterized by being able to obtain tomographic image data of a part of the subject.
T-scanner. - (2) The subject holding means in the reversing drive system includes a pair of lower side pieces and a pair of upper side pieces so as to sandwich the subject from both sides, respectively, from the lower side and the upper side of the upright rotating frame part. 2. The industrial CT scanner according to claim 1, wherein a subject fixing body is provided inside the lower side piece and the upper side piece so as to protrude. (3) The industrial CT scanner according to claim 1, wherein the subject fixing body is movable in position with respect to the lower side piece and the upper side piece.