JP7779659B2 - Radiation Inspection Equipment - Google Patents

Description

This embodiment relates to an inline-type radiological inspection device.

Radiation inspection devices such as X-ray CT scanners are equipped with a radiation source that emits radiation, for example, an X-ray beam, and a detector that is positioned opposite the radiation source and detects the X-ray beam. An inspection table on which the object to be inspected is placed is located between the radiation source and the detector, and this inspection table rotates once while the X-ray beam is irradiated onto the object to be inspected, thereby obtaining fluoroscopic images from all directions. CT images of the object to be inspected are obtained by reconstructing these fluoroscopic images. It is known to incorporate such radiation inspection devices into the production line of the objects to be inspected, and such devices are called inline types.

Conventionally, inline inspection equipment is installed along an inspection object transport line, such as a belt conveyor or chain conveyor, and inspected objects are removed from the line and moved to the inspection equipment, then returned to the line after inspection is complete. In this case, since the radiation inspection equipment uses a radiation source, it is installed in a shielded room near the line, and objects are moved in and out of the line to the inspection equipment inside the shielded room using a crane or robot.

Japanese Patent Application Publication No. 5-264476 Japanese Patent Application Publication No. 2-184839 Japanese Patent Application Laid-Open No. 2019-194582

However, with these conventional technologies, when incorporating an inspection device into a production line, it was necessary to manually set the object to be inspected onto the sample table inside the inspection device. One method is to use a robot to set the object from the line onto the sample table instead of manually, but even in this case, it is necessary to stop the radiation irradiation, open the sample door, and set the object to be inspected onto the inspection device's sample table. This necessitates the need to turn the radiation off, open and close the sample door, and turn the radiation on again, which creates the problem of extending the inspection work time.

To remedy this, one technology involves installing two sample doors between the line and the inspection device, with a robot or similar device positioned between each sample door. With this technology, the robot alternately opens and closes the two sample doors when moving the test object from the line, preventing radiation leakage even when the radiation is always on. However, even with this conventional technology, there are problems with the need for two sample doors and multiple robots or similar devices to move the test objects.

This embodiment has been proposed to solve the above-mentioned problems. In other words, the purpose of this embodiment is to provide a radiation inspection device that can minimize the inspection work time by eliminating the need to turn radiation irradiation on and off or open and close the sample door each time an inspection object is placed in or removed, and that allows the inspection object to be placed on the sample table unmanned.

The radiation inspection apparatus of the embodiment has the following configuration.
(1) An inspection device body including a sample table on which an object to be inspected is placed, and a radiation source and a detector disposed on either side of the sample table.
(2) A shielded chamber including a housing section for the inspection device main body and a transport section for the object to be inspected that is provided separately from the housing section for the inspection device main body.
(3) A transport device that transports the object to be inspected from outside the shielding chamber into the transport section through an entrance and an exit provided in the transport section.
(4) A transfer device provided in the shielding chamber for transferring the object to be inspected between the transport device located in the transport section and the sample table.
(5) A shielding wall provided between the housing section of the inspection device main body and the transport section of the object to be inspected in the shielding chamber, the shielding wall having an opening that serves as a movement path for the object to be inspected in the transfer device.

The radiation inspection apparatus according to the embodiment may further include the following configuration.
(1) The sample table has a plurality of placement locations for the object to be inspected, and when one of the placement locations is located in the radiation irradiation area between the radiation source and the detector, the other placement locations are outside the radiation irradiation area, and the transfer device moves the object to be inspected between the placement location located outside the radiation irradiation area and the transport device.
(2) The transfer device is a robot that is placed in the shielded chamber and has an arm that grips the object to be inspected.
(3) The transfer device is a crane that is disposed on the ceiling of the shielding chamber and that moves the object to be inspected while suspending it between the transport device and the sample table.

FIG. 1 is a plan view showing a radiological inspection apparatus according to a first embodiment. FIG. 1 is a longitudinal sectional view showing a radiological inspection apparatus according to a first embodiment; FIG. 2 is a block diagram showing the configuration of a detector in the first embodiment. FIG. 10 is a plan view showing a radiological inspection apparatus according to a second embodiment. FIG. 10 is a longitudinal sectional view showing a radiological inspection apparatus according to a second embodiment.

1. First embodiment
[1-1. Configuration]
Hereinafter, the radiological inspection apparatus of the first embodiment will be described with reference to FIGS. 1 and 2. FIG.
The inspection device of this embodiment includes a shielded chamber 1 having a radiation shielding function. The shielded chamber 1 includes a storage section 1a for the inspection device main body, and a transport section 1b for the object to be inspected W that is provided separately from the storage section 1a for the inspection device main body. A shielding wall 2 having a radiation shielding function is provided between the storage section 1a for the inspection device main body and the transport section 1b for the object to be inspected W. The shielding wall 2 has an opening 3 that serves as a path for the object to be inspected W to move.

In this embodiment, an X-ray CT scanner is used as the inspection device main body, but it may also be a simple transmission-type radiation detector. The inspection device main body has a sample table 4 on which the object to be inspected W is placed, and a radiation source 5 and detector 6 arranged on either side of the sample table 4. The radiation source 5 irradiates the object to be inspected W with a cone-shaped X-ray beam B, and the X-ray beam B that passes through the object to be inspected W is detected by the detector 6 as X-ray transmission data.

In this embodiment, the sample table 4 has two placement sections for the object to be inspected. Specifically, the sample table 4 has a support section 7 that moves in a direction intersecting the optical axis of the X-ray beam B, and two turntables 8a and 8b aligned on the support section 7 along the direction of movement. These turntables 8a and 8b are placement sections for the object to be inspected W. The two turntables 8a and 8b are mounted on the support section 7 so that when one turntable 8a is in a perspective position within the X-ray beam B, the other turntable 8b is in a position outside the irradiation range of the X-ray beam B, i.e., in a transfer position for the object to be inspected W. The sample table 4 has a table switching mechanism 9 and a drive mechanism (not shown) for the turntables 8a and 8b. The table switching mechanism 9 has a drive mechanism such as a linear motor and moves the support section 7 so that the two turntables 8a and 8b are alternately positioned inside and outside the X-ray beam B.

The transport section 1b for the objects to be inspected W is located within the shielded chamber 1, sandwiching the shielding wall 2 as described above. The transport section 1b is provided with an entrance 10 and an exit 11, and a transport device 12 passes through the entrance 10 and exit 11 to transport the objects to be inspected W from outside the shielded chamber 1 into the transport section 1b. The transport device 12 may be a conveyor such as a chain conveyor, belt conveyor, or bucket conveyor, or a chute or other device. In this embodiment, a conveyor is used that transports the objects to be inspected W while they are placed at predetermined intervals.

The object to be inspected W may be placed directly on the transport device 12, but in this embodiment, the object to be inspected W is supported on a holder 13, and the object to be inspected W is transported together with the holder 13. It is also preferable to provide a circular plate at the bottom of the holder 13 for lifting by the arm of the robot 15 or the claw of the crane 16, which will be described later, to prevent the object to be inspected W or the holder 13 from slipping off the claw of the robot 15 or crane 16 and falling.

A sorting device 14 for non-defective and defective products is provided downstream of the exit 11 of the shielding chamber 1 on the conveying device 12. Any known sorting device 14 can be used as appropriate, but for example, a device can be used that sends non-defective products to the non-defective product line 12a of the conveying device 12, and, when defective products are transported, uses a push rod or robot arm to eject the inspection object W from the conveying device 12 to the defective product line 12b.

A transfer device is provided near the opening 3 in the shielding wall 2 to transfer the object to be inspected between the transport device 12 and the turntables 8a and 8b. In this embodiment, a robot 15 installed in the storage section 1a for the object to be inspected is used as the transfer device. The robot 15 has a main body installed in the storage section 1a and an articulated arm extending from the main body. The articulated arm is inserted from the opening 3 toward the transport device 12 to grasp and pick up the object to be inspected W, and then extends beyond the irradiation range of the X-ray beam B to place the object to be inspected on the turntable 8b, which is outside the irradiation range.

As shown in FIG. 3, the detector 6 is connected to a reconstruction unit 20 that generates CT images based on the X-ray transmission data obtained by the detector 6, and a judgment unit 21 that judges whether the inspection object W is a good or bad product based on the CT images obtained by the reconstruction unit 20. The output side of the judgment unit 21 is connected to a sorting control unit 22, which controls the sorting operation of the sorting device 14 to sort good and bad products.

[1-2. Effect]
In this embodiment, the inspection object W is placed on a transport device 12 and carried into the transport section 1b of the shielding chamber 1 through the entrance 10. The inspection object W on the transport device 12, together with the holder 13, is lifted from above the transport device 12 by a robot 15, passes through the opening 3 in the shielding wall 2, and is placed on the turntable 8b located outside the X-ray beam B. In this state, the table switching mechanism 9 moves the support section 7 in a direction intersecting the X-ray optical axis, and the turntable 8b located outside the X-ray beam B is positioned within the X-ray beam B.

The turntable 8a rotates within the X-ray beam B, and X-ray transmission data from all directions around the object W to be inspected is collected by the detector 6. This X-ray transmission data from all directions is subjected to image reconstruction calculations by the reconstruction unit 20 to generate a CT image of the object W. After X-ray transmission data collection is complete, the object W is moved outside the X-ray beam B together with the support unit 7 and turntable 8a by the table switching mechanism 9. After inspection, the object W is returned to the transport device 12 by the robot 15 outside the X-ray beam B.

The judgment unit 21 judges whether the inspection object W is good or bad based on the generated CT image, and based on the result, the sorting control unit 22 operates the sorting device 14 to sort good products to the good product line 12a of the conveying device 12 and defective products to the defective product line 12b.

While data is being collected for the object W on turntable 8a that has been moved into the X-ray beam B, the object W on turntable 8b, for which data collection has been completed earlier and which has been moved outside the X-ray beam B, is returned to the transport device 12 by the robot 15, and the next uninspected object W is placed from the transport device 12 on the turntable 8b outside the X-ray beam B. In this way, the table switching mechanism 9 can move the turntable 8a carrying the inspected object W outside the X-ray beam B, while simultaneously moving the turntable 8b carrying the next uninspected object W to the irradiation position of the X-ray beam B. As a result, X-ray transmission data for multiple objects W can be obtained continuously.

[1-3. Effects]
(1) In this embodiment, the transport device 12 is disposed inside the shielded chamber 1, and further, the shielding wall 2 is provided between the housing section 1a of the inspection device main body and the transport section 1b of the inspection object W inside the shielded chamber 1. This prevents X-rays scattered by the inspection object W or the like from leaking outside the shielded chamber 1. As a result, the radiation source 5 can be kept on at all times, thereby shortening the inspection time.
(2) By providing two turntables 8a and 8b and moving them alternately within the irradiation range of the X-ray beam B, there is no need to wait for the work of replacing the object to be inspected W, which also reduces the inspection time.
(3) There is no need to install a door for bringing the object W into or out of the shielding chamber 1, and the entrance 10 and exit 11 of the transport section 1b and the opening 3 of the shielding wall 2 are all always open, so the object W can be moved smoothly from outside the shielding chamber 1 to the irradiation area of the X-ray beam B in a short time.

[2. Second embodiment]
A second embodiment will be described with reference to Figures 4 and 5. In the second embodiment, a ceiling crane is used as a transfer device instead of the robot 15 of the first embodiment. That is, a crane 16 is provided in the ceiling of the shielded room 1, penetrating the opening 3 in the shielding wall 2 and extending from the transport unit 1b to the turntable 8b outside the irradiation range. A lifting section 16a of the crane 16 is provided with a claw-like gripping section 16b that opens and closes, and the inspection object W is transferred between the transport unit 12 and the turntable 8b while being clamped from above by this gripping section 16b.

In the second embodiment having this configuration, as in the first embodiment, the inspection object W can be transported inside the shielded chamber 1 while the radiation source 5 remains on. Furthermore, by providing two turntables 8a and 8b on the support part 7, it is possible to transport the inspection object W and perform a CT scan simultaneously, thereby shortening the inspection time.

3. Other Embodiments
Although multiple embodiments according to the present invention have been described herein, these embodiments are presented as examples and are not intended to limit the scope of the invention. The above-described embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the scope of the invention. These embodiments and their modifications are intended to be included within the scope and spirit of the invention, as well as within the scope of the invention and its equivalents as set forth in the claims.

For example, in the illustrated embodiment, there are two turntables, 8a and 8b, but a single turntable may be used, although this will require additional inspection time. In this case, after transmission data collection is complete, the inspection object W is returned to the conveyor, and the next inspection object W is placed on a turntable outside the irradiation range from the transport device 12. Three or more turntables may also be used.

Transfer devices other than the crane 16 and robot 15 can also be used. When using a simple transmission type radiation detection device other than CT, a placement section for the object W to be inspected, such as a positioning member or stopper, can be provided on the support section 7 without using a turntable as a placement section for the object W to be inspected.

W...inspection object B...X-ray beam 1...shielding chamber 1a...storage section 1b of inspection apparatus main body...transport section 2 of inspection object...shielding wall 3...opening 4...sample table 5...radiation source 6...detector 7...support sections 8a, 8b...turntable 9...table switching mechanism 10...entrance 11...exit 12...transport device 12a...good product line 12b...defective product line 13...holder 14...sorting device 15...robot 16...crane 16a...lifting section 16b...gripping section 20...reconstruction section 21...determination section 22...sorting control section

Claims (3)

an inspection apparatus body including a sample table on which an object to be inspected is placed, and a radiation source and a detector disposed on either side of the sample table;
a shielded chamber including a housing section for the inspection device main body and a transport section for the object to be inspected that is provided separately from the housing section for the inspection device main body;
a conveying device that conveys the object to be inspected from outside the shielding chamber into the conveying section through an entrance and an exit provided in the conveying section;
a transfer device provided in the shielding chamber and configured to move the object to be inspected between the transport device located in the transport unit and the sample table;
a shielding wall provided between the housing unit of the inspection device main body and the transport unit of the object to be inspected in the shielding chamber, the shielding wall having an opening that serves as a movement path of the object to be inspected in the transfer device;
Equipped with
the sample table includes two turntables as locations for placing the object to be inspected ;
a table switching mechanism that moves the sample table so as to alternately form a state in which one of the two turntables is placed at an inspection position that is a radiation irradiation area and the other is placed at a transfer position that is outside the radiation irradiation area ,
When one of the two turntables is located in the radiation irradiation area, the other turntable is located outside the radiation irradiation area;
The transfer device is a radiation inspection apparatus that moves the inspection object between the turntable located outside the radiation irradiation area and the transport device. The radiological inspection apparatus according to claim 1, wherein the transfer device is a robot arranged in the shielded chamber and having an arm that grasps the object to be inspected. The radiological inspection apparatus of claim 1, wherein the transfer device is a crane located in the ceiling of the shielded room and suspends and moves the inspection object between the transport device and the sample table.