JPH06133959A - Bed for tomography - Google Patents

Abstract

PURPOSE:To prevent generation of dust or the like when conveying an examinee by supporting a bed for tomography using a bed support means without contact, and conveying the subject into a cavity by means of a shifting magnetic field. CONSTITUTION:Two lifts 10 which freely move in the vertical direction are secured to a floor surface to sandwich the cavity 5 of a gantry 4 therebetween, and a support stand 11 is provided through the inside of the cavity 5 of the gantry 4. A plurality of bed-moving electromagnets 12 are arranged in two lines along the longitudinal direction of the support stand 11 and embedded in the upper surface of the support stand 11. Currents are fed to the bed-moving electromagnets 12 so that a shifting magnetic field is produced in the longitudinal direction of the support stand 11. A bed 14 for tomography on which an examinee 13 is placed is levitated above the shifting magnetic field without contact with the support bed 11 or the like using a bed-levitating electromagnet 15, with a gap provided above the support stand 11. The bed-levitating electromagnet 15 is formed on the inside wall 11a of the support stand 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is provided, for example, in an industrial tomography apparatus (CT scanner apparatus) or a medical CT scanner apparatus for inspecting internal damage (cracks, peeling, etc.) of semiconductor devices, etc. The present invention relates to a tomography bed for placing a sample and transporting the sample into the cavity of the gantry.

[0002]

2. Description of the Related Art As shown in FIG. 3, a bed provided in a conventional CT scanner device is mounted on a base 1 fixed to the floor so as to be vertically movable and horizontally movable. . A subject 3 (a semiconductor device or the like in the case of an industrial CT scanner device, a patient in the case of a medical CT scanner device) is placed on this bed 2, and in that state, the subject 3 is placed in the cavity 5 of the gantry 4. The bed 2 is horizontally moved to the position shown by the chain double-dashed line in the figure so as to insert.

The bed 2 is horizontally moved by, for example, a rack mounted in the horizontal movement direction and a mechanical mechanism for rotating a pinion meshing with the rack with a motor.

[0004]

However, the conventional example having such a structure has the following problems. That is, if the bed is horizontally moved by the mechanical mechanism as in the conventional example, there is a problem that dust and oil are generated when the bed is horizontally moved, and a clean environment cannot be maintained. In such a case, for example, if the subject is a precision device such as a semiconductor device, it may cause a failure of the semiconductor device, and if the subject is a person (patient), it may be unhealthy. Will be given.

The present invention has been made in view of such circumstances, and an object thereof is to provide a tomography bed in which dust or the like does not occur when a subject is transported into a gantry.

[0006]

The present invention has the following constitution in order to achieve such an object. That is, in the present invention, in a tomographic bed for placing a subject and transporting the subject into the cavity of the gantry, a support table that is supported by penetrating the cavity of the gantry, and the support table. Moving magnetic field forming means for forming a moving magnetic field on top,
Bed moving means for supporting the tomographic bed in a non-contact state by providing a gap above the moving magnetic field formed by the moving magnetic field forming means, the moving magnetic field forming means of the tomographic bed forming the moving magnetic field. The portion facing the moving magnetic field is formed of a conductor.

[0007]

The operation of the present invention is as follows. The tomography bed on which the subject is placed is supported in a non-contact state by providing a gap above the moving magnetic field formed by the moving magnetic field forming means by the bed supporting means. Further, the moving magnetic field shaping means forms a moving magnetic field on a support which is supported by penetrating the cavity of the gantry. Since the portion of the tomography bed facing the moving magnetic field means is formed of a conductor, the moving magnetic field shaping means shapes the moving magnetic field so that the moving magnetic field formed by the stator and the tomographic bed is two. Acting as a secondary conductor, the tomography bed moves horizontally on a support base according to the principle of a linear motor (linear induction motor) and conveys the subject into the cavity of the gantry.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view taken along the longitudinal direction of a bed of a CT scanner device equipped with a tomographic bed according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along the lateral direction of the bed of the embodiment device. It is a figure. Note that the gantry is not shown in FIG. Further, in this embodiment, an industrial CT scanner device for inspecting a semiconductor device will be described as an example.

Two lifts 10 that can be raised and lowered are fixed to the floor so as to sandwich the cavity 5 of the gantry 4, supported by the upper portions of the lifts 10 and penetrating through the cavity 5 of the gantry 4. A support base 11 is provided. Support stand 11
A plurality of bed moving electromagnets 12 are arranged in two rows in the longitudinal direction of the support 11 and are recessed on the upper surface of the. A current is supplied to these bed moving electromagnets 12 from a power supply unit (not shown) so as to form a moving magnetic field in the longitudinal direction of the support 11.

Above the moving magnetic field formed in this way, the tomographic imaging bed 14 on which the subject 13 (semiconductor device) is placed has its longitudinal direction aligned with the longitudinal direction of the support 11. , Support base 1 by electromagnet 15 for bed levitation
A space is provided on the substrate 1 and is levitated in a non-contact state with the support base 11 and the like. The tomographic bed 14 is made of aluminum (A
1) and the like, a plate-shaped main body portion 14a and a levitation support portion 14b formed of a magnetic material such as iron provided on both side surfaces in the longitudinal direction of the main body portion 14a. .

Further, a plurality of magnetic cores 15a are attached to the inner side wall 11a of the support base 11 having a cross section in the lateral direction formed in a U shape, along the longitudinal direction of the support base 11, respectively. A coil is wound around each of the magnetic cores 15a to form the bed levitation electromagnet 15. Power is supplied to these bed levitation electromagnets 15 from a power supply unit (not shown).

The bed moving electromagnet 12 corresponds to the moving magnetic field forming means in the present invention, and the bed levitation electromagnet 15 and the levitation support portion 14b constituting the tomographic imaging bed 14 are the bed in the present invention. It corresponds to a supporting means.

The operation of the CT scanner device having the above configuration will be described below. The tomographic bed 14 has a magnetic force generated by the bed levitation electromagnet 15 and the tomographic bed 14
Due to its balance with its own weight, it is levitated in a non-contact state with the support stand 11, the electromagnet 15 for raising the bed, and the like. That is,
The levitation support portion 14b of the tomography bed 14 is attracted by the magnetic force generated from the bed levitation electromagnet 15, and the tomography bed 14 is levitated by providing a gap on the support base 11. At this time, the levitation support is performed. In order to prevent the portion 14b from being attracted to the bed levitation electromagnet 15, the bed levitation electromagnet 15
The magnetic force generated from is adjusted by, for example, the amount of current supplied. The bed levitation electromagnet 15 also functions as a guide for the tomographic imaging bed 14 when the tomographic imaging bed 14 is moved horizontally, which will be described later.

Further, a tomography bed 14 having a main body portion 14a made of a conductor is formed by a linear motor (linear induction) by forming a moving magnetic field by the bed moving electromagnet 12 in the longitudinal direction of the tomography bed 14. According to the principle of "motor", it moves horizontally, that is, moves in the longitudinal direction of the tomographic imaging bed 14. This is because the bed moving electromagnet 12 in which a moving magnetic field is formed in the longitudinal direction of the tomographic bed 14 serves as a stator, and the main body portion 14a is formed of a conductor of the tomographic bed 14 that is levitated above the moving magnetic field. Because it acts as a secondary conductor. At the time of this horizontal movement, both sides in the lateral direction of the tomographic bed 14 are attracted to the bed levitation electromagnet 15 described above, so the tomographic bed 14 is balanced in the lateral direction. You can move horizontally while keeping it.

Next, the procedure of tomography of the subject 13 will be described. First, the subject 13 is placed on the tomographic imaging bed 14 that is levitated outside the cavity 5 of the gantry 4. Next, a moving magnetic field is generated by the bed moving electromagnet 12 so that the subject 13 placed on the tomographic bed 14 is moved to a predetermined position in the cavity 5 of the gantry 4. Thereby, as described above, the tomographic imaging bed 14 horizontally moves, and the subject 13 is transported into the cavity 5 of the gantry 4.
Then, the two lifts 10 are synchronously moved up and down to adjust the height of the subject 13 in the cavity 5 of the gantry 4, and tomography of the subject 13 is performed. When the imaging is completed, a moving magnetic field is generated by the bed moving electromagnet 12 so as to move the subject 13 to the outside of the cavity 5 of the gantry 4, and when the subject 13 is transported to the outside of the cavity 5 of the gantry 4, The specimen 13 is taken out from the tomographic bed 14.

In the above-described embodiment, the tomography bed 14 is levitated by the balance between the magnetic force of the bed levitation electromagnet 15 and the weight of the tomography bed 14 itself. Electromagnets are arranged on the inner side walls 11a of the table 11 so as to face each other, and the levitation support portion 14b of the tomography bed 14 is placed between the electromagnets.
The (magnetic material) may be sandwiched so that the tomographic imaging bed 14 is levitated by the balance of the magnetic forces generated by both electromagnets.

In the above embodiment, the industrial CT scanner device for inspecting the semiconductor device has been described as an example, but the present invention is a bed of other industrial CT scanner devices and medical CT scanner devices. It can also be applied as a horizontal moving mechanism.

[0018]

As is apparent from the above description, according to the present invention, the tomographic bed on which the subject is placed is moved horizontally by the moving magnetic field in a non-contact state by the bed supporting means, and the subject is moved. Since it is configured to be transported into the cavity of the gantry, it is possible to prevent dust and oil from being generated during horizontal movement. Therefore, it is possible to realize a tomography bed that maintains a clean environment and does not adversely affect the subject.

[Brief description of drawings]

FIG. 1 is a cross-sectional view taken along the bed longitudinal direction of a CT scanner device including a tomographic imaging bed according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the apparatus of the embodiment taken along the lateral direction of the bed.

FIG. 3 is a diagram showing a schematic configuration of a CT scanner device including a tomographic imaging bed according to a conventional example.

[Explanation of symbols]

 4 ... Gantry 5 ... Gantry cavity 10 ... Lift 11 ... Support 12 ... Bed moving electromagnet 13 ... Subject 14 ... Tomography bed 14a ... Tomography bed body 14b ... Tomography bed floating support 15… Electromagnet for bed levitation

Claims (1)

[Claims] 1. A tomographic bed for placing a subject and for transporting the subject into the cavity of the gantry, and a support stand that is supported by penetrating the inside of the cavity of the gantry, and on the support stand. A moving magnetic field forming means for forming a moving magnetic field in the, and a bed supporting means for supporting the tomography bed in a non-contact state by providing a gap above the moving magnetic field formed by the moving magnetic field forming means, A tomography bed, wherein a portion of the tomography bed facing the moving magnetic field formed by the moving magnetic field shaping means is formed of a conductor.