JP3582900B2 - table - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a table of an MR (Magnetic Resonance) device, and more particularly, an upper structure that slidably holds a cradle on which a subject is placed is moved up and down with respect to a floor via a parallel movement mechanism. About the table.
[0002]
[Prior art]
When a subject is placed in a uniform and strong static magnetic field, the nuclear spins of the subject perform precession about the direction of the static magnetic field at a frequency (Larmor frequency) determined by the strength of the static magnetic field. Then, when an electromagnetic wave of a high-frequency pulse having a frequency equal to the Larmor frequency is transmitted from the transmission / reception coil, spins are excited and transit to a high energy state. This is called a nuclear magnetic resonance phenomenon. Then, when the transmission of the high frequency pulse electromagnetic wave is terminated, the spin returns to the original low energy state with a time constant corresponding to each state, and at this time, the electromagnetic wave is transmitted to the outside.
[0003]
The MR device detects this electromagnetic wave with a high-frequency receiving coil tuned to that frequency, measures the nuclear spin density distribution, relaxation time distribution, and the like at a desired examination site in the subject, and uses the measured data to determine the subject's The section is displayed as an image.
[0004]
Next, a table used in a conventional MR apparatus will be described with reference to the drawings. 6 is an overall configuration diagram of a conventional MR apparatus, FIG. 7 is a plan view of the table in FIG. 6, and FIG. 8 is a left side view of the table in FIG.
[0005]
In these figures, reference numeral 1 denotes a through hole 1a into which a subject is inserted, a magnet for generating various magnetic fields in the through hole 1a, an electromagnetic wave transmitted to the subject, and an electromagnetic wave received from the subject. A magnet unit provided with a coil.
[0006]
Reference numeral 2 denotes a table on which the subject is placed and which transports the subject into the through hole 1a of the magnet unit 1.
The table 2 performs a circular motion while maintaining a parallel state with respect to the floor 3 via a base 4 provided on the floor 3 and a parallel movement mechanism, for example, a parallel link (crank) mechanism 5, and moves up and down with respect to the floor 3. And the upper structure 6 which is formed.
[0007]
A cradle 7 on which the subject is placed is provided on the upper structure 6 so as to be slidable in the direction of the magnet unit 1.
Next, the structure of the upper structure will be described with reference to FIG. FIG. 9 is a cross-sectional view taken along section line AA of FIG.
[0008]
In the drawing, reference numeral 10 denotes an upper cover made of fiber reinforced plastics (FRP) that covers the upper part of the upper structure 6, and 11 denotes a lower cover made of FRP that covers the lower part of the upper structure 6.
[0009]
12 are side frames provided on both sides of the upper structure 6 along the longitudinal direction. The conventional side frame 12 uses an aluminum square pipe.
[0010]
Reference numeral 13 denotes an upper connection frame whose end is welded to the side surface of each side frame 12 and connects the side frames 12, and 14 denotes a lower connection whose end is welded to the bottom surface of each side frame 12 and connects the side frames 12. It is a frame.
[0011]
The upper cover 10 is attached to the upper connection frame 13 using screws 15. The cradle 7 slides on the upper cover 10.
Further, reference numeral 16 denotes a bracket to which the swing link of the parallel link mechanism 5 welded to the bottom surface of the side frame 12 is pivotally attached.
[0012]
[Problems to be solved by the invention]
However, in the table having the above configuration, since the upper cover 10 and the lower cover 11 are made of FRP, there is a problem that the cost is high.
[0013]
Also, in the upper cover 10 attached to the upper connection frame 13 using the screws 15, if the screws 15 are tightened unevenly, the portion B facing the cradle 7 is deformed, and the gap between the cradle 7 and the upper cover 10 becomes improper. There is also a problem that when the cradle 7 is moved, a finger or the like of the subject is trapped in the gap.
[0014]
The present invention seeks to provide an inexpensive and secure table.
[0015]
[Means for Solving the Problems]
The present invention for solving the above-mentioned problems is directed to a table in which an upper structure that slidably holds a cradle on which a subject is placed is raised and lowered with respect to a floor via a parallel movement mechanism, wherein the upper structure has a longitudinal shape. First and second frames arranged side by side in the direction, the first and second frames face an exposed surface exposed on a side portion of the upper structure, and a lower portion of the cradle; And a cradle facing surface on which the cradle slides.
[0016]
Since the first and second frames of the table of the present invention have the exposed surface exposed on the side of the upper structure, a cover for covering the side is not required, and the cost can be reduced.
[0017]
Further, the first and second frames face the lower part of the cradle and have a cradle-facing surface on which the cradle slides, so that the gap between the cradle and the upper structure is constant, and the first and second frames are covered when the cradle is moved. An accident or the like in which the finger of the sample is caught in the gap can be prevented.
[0018]
Further, from the viewpoint of reducing the number of assembling steps and costs, it is desirable that the first and second frames are provided with a mounting surface on which the parallel motion mechanism is mounted.
Further, as a specific manufacturing method and material of the first and second frames, there is an extruded aluminum material.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a side cross-sectional view of a table according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line BB of FIG. 2. FIG. 3 is a side view of the table according to the embodiment of the present invention, FIG. 4 is a plan view in FIG. 3, and FIG. 5 is a right side view in FIG.
[0020]
First, an overall configuration of a table according to an embodiment of the present invention will be described with reference to FIGS. In these figures, 21 is formed with a through hole 21a into which a subject is inserted, a magnet for generating various magnetic fields in the through hole 21a, transmitting electromagnetic waves to the subject, and receiving electromagnetic waves from the subject. A magnet unit provided with a coil.
[0021]
Reference numeral 22 denotes a table on which the subject is placed and which transports the subject into the through hole 21a of the magnet unit 21.
The table 22 includes a base 24 provided on the floor 23, and an upper structure 26 which moves up and down with respect to the floor 23 via an X-arm mechanism as a parallel movement mechanism described later.
[0022]
The cradle 27 on which the subject is placed is provided on the upper structure 26 so as to be slidable in the direction of the magnet unit 21.
Next, the parallel movement mechanism of the present embodiment will be described with reference to FIG. In the figure, a guide 31 extending parallel to the floor 23 is provided on a frame 30 of the upper structure 26, and a guide 32 extending parallel to the floor 23 is also provided on the base 24.
[0023]
A first end 33 is rotatably provided on a base 34, and a top end is rotatably provided on a slider 34 slidably engaged with a guide 31 provided on a frame 30 of the upper structure 26. Arm.
[0024]
An upper end 35 is rotatably provided on the frame 30, an intermediate portion is rotatably attached to an intermediate portion of the first arm 33 using a pin 36, and a lower end slides on a guide 32 provided on the base 24. This is a second arm rotatably provided on a slider 37 movably engaged.
[0025]
Reference numeral 38 denotes a cylinder driven at the lower end by pneumatic or hydraulic pressure provided rotatably with respect to the base 24. The distal end of the rod 39 of the cylinder 38 is rotatably attached to the second arm 35.
[0026]
Therefore, a so-called X-arm type parallel movement mechanism is formed by the frame 30 of the upper structure 26, the first and second arms 33 and 35, and the base 24, and the upper structure 26 drives the cylinder 38. As a result, the robot moves up and down in parallel with the floor 23. Reference numeral 40 denotes a vertically expandable and contractable skirt that covers the X-arm parallel movement mechanism, and reference numeral 41 denotes a front cover provided at an end of the cradle 27 opposite to the end facing the magnet unit 21.
[0027]
The major difference between the table 22 of the present embodiment and the table described in the conventional example is that the table of the conventional example moves up and down while swinging with respect to the floor. Although a gap is required between the table 22 and the table 22, the table 22 of the present embodiment moves up and down without swinging, so that the table 22 is provided in contact with the magnet unit 21.
[0028]
Next, the structure of the upper structure 26 will be described with reference to FIG. In the figure, a frame 30 is composed of first and second frames 51 and 52 arranged side by side in the longitudinal direction. The first and second frames 51 and 52 face the exposed surfaces 51 a and 52 a exposed on the side surface of the upper structure 26 and the lower portion of the cradle 27, and the cradle facing the sliding member 27 a of the cradle 27 slides. Surfaces 51b and 52b and mounting surfaces 51c and 52c to which the first and second arms 33 and 35 of the parallel movement mechanism are mounted are formed. The first and second frames 51 and 52 of the present embodiment were manufactured from an extruded aluminum material.
[0029]
Further, reference numeral 60 denotes an upper cover made of FRP (fiber reinforced plastics) provided at an upper portion between the two frames 51 and 52 of the upper structure 26, and 61 denotes two frames 51 and 52 of the upper structure 26. It is a lower cover made of FRP provided in a lower portion between 52.
[0030]
In the table having the above configuration, since the first and second frames 51 and 52 have the exposed surfaces 51a and 52a exposed on the side of the upper structure 26, a cover for covering the side is unnecessary. Cost reduction can be achieved.
[0031]
The first and second frames 51 and 52 face the lower portion of the cradle 27 and have cradle facing surfaces 51b and 52b on which the cradle 27 slides. Is constant, and it is possible to prevent an accident or the like in which the finger of the subject is caught in this gap when the cradle 27 moves.
[0032]
Further, since the first and second frames 51 and 52 are provided with the mounting surfaces 51c and 52c on which the parallel movement mechanism is mounted, the number of assembling steps and costs can be reduced.
[0033]
【The invention's effect】
As described above, according to the table of the present invention, since the first and second frames of the table have the exposed surfaces exposed on the side of the upper structure, the cover for covering the side is unnecessary. Cost can be reduced.
[0034]
Further, since the first and second frames have a cradle-facing surface that faces the lower part of the cradle and slides the cradle, the gap between the cradle and the upper structure becomes constant, and the first and second frames are covered when the cradle moves. An accident or the like in which the finger of the sample is caught in the gap can be prevented.
[0035]
Further, since the first and second frames are provided with mounting surfaces on which the parallel movement mechanism is mounted, the number of assembly steps and costs can be reduced.
[Brief description of the drawings]
FIG. 1 is a side sectional view of a table according to an embodiment of the present invention, which is a sectional view taken along a cutting line BB in FIG. 2;
FIG. 2 is a side sectional view of a table according to the embodiment of the present invention.
FIG. 3 is a side view of a table according to the embodiment of the present invention.
FIG. 4 is a plan view of FIG.
FIG. 5 is a right side view in FIG. 3;
FIG. 6 is an overall configuration diagram of a conventional MR device.
FIG. 7 is a plan view of the table in FIG. 6;
FIG. 8 is a right side view of the table in FIG. 6;
FIG. 9 is a cross-sectional view taken along line AA of FIG. 7;
[Explanation of symbols]
26 Upper Structure 27 Cradle 51 First Frames 51a, 52a Exposed Surfaces 51b, 52b Cradle Opposing Surfaces 51c, 52c Mounting Surface

Claims (3)

An upper structure that slidably holds a cradle on which the subject is placed is moved up and down with respect to the floor via a parallel movement mechanism,
The upper structure has first and second frames arranged side by side in the longitudinal direction,
The table, wherein the first and second frames have an exposed surface exposed on a side portion of the upper structure, and a cradle facing surface on which the cradle slides while facing a lower portion of the cradle. The table according to claim 1, wherein the first and second frames have a mounting surface to which the parallel movement mechanism is mounted. The table according to claim 1 or 2, wherein the first and second frames are extruded aluminum.

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