JPS63107006A - Magnetic field generator simultaneously adjusting position of magnetic pole - Google Patents

Abstract

PURPOSE:To conduct the centering of upper and lower magnetic poles and the uniform adjustment of a magnetic field easily by readily adjusting the position of a pole plate by movably supporting the pole plate before and behind and left and right. CONSTITUTION:In a magnetic field generator consisting of oppositely arranged permanent magnets 1, pole plates 4 mounted to the opposed surfaces of these permanent magnets 1 and a yoke 3 magnetically coupling the permanent magnets 1 and generating a magnetic field between the pole plates 4, said pole plates 4 are supported movably before and behind and left and right. Bolts B1, B2 extending to the left and the right the outer circumference of the pole plate 4 and bolts B3, B4 elongating before and behind are fixed to the pole plate 4. A pole plate fitting 5, which consists of a nonmagnetic material, has four bolt support sections 5a projected from the upper surface of which and takes a cylindrical shape and to which slots 5b from which the bolts B1-B4 for the pole plate 4 are each inserted to the support sections 5a are shaped, is mounted onto the outer circumference of the permanent magnet 1. The pole plate 4 is fitted to the pole plate fitting 5 by nuts 6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Field of Application) The present invention relates to a magnetic field generating device that forms a static magnetic field in, for example, MRI, and particularly to a magnetic field generating device whose magnetic pole position is adjustable.

(Prior Art) Generally, this type of magnetic field generating device consists of permanent magnets 1.1 arranged opposite to each other as shown in FIG.
．． 1 and the permanent magnet 1.
．． 1 and a yoke 3 that magnetically couples the magnetic pole plates 2 and 2, and generates a magnetic field between the magnetic pole plates 2, 2.

In this type of device, it is necessary to align the centers of the upper and lower magnetic poles and adjust the set position of the magnetic pole plates in the front, back, left and right directions so that the magnetic field in the gap between the magnetic poles becomes uniform.

(Problems to be Solved by the Invention) However, the conventional device shown in FIG. Since the a-pole plate 2 is fixed to the facing surface of the permanent magnet 1 by adhesion or bolting, it is extremely difficult to adjust the position of the magnetic pole plate 2.

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the conventional device as described above, and to make it possible to easily adjust the position of the magnetic pole plate.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention has a structure in which the magnetic pole plate is supported so as to be movable back and forth and left and right.

(for production) Since the present invention has the above configuration, it operates as follows.

That is, since the magnetic pole plate is supported so as to be movable back and forth, left and right, the mounting position of the magnetic pole plate can be freely adjusted, and therefore the centering of the upper and lower magnetic poles and the uniformity of the magnetic field can be easily adjusted.

(Example) The illustrated embodiment will be described below.

FIG. 1 is a front sectional view showing an embodiment of the magnetic field generator with magnetic pole position adjustment according to the present invention, and FIG. 2 is a view taken along line A-A in FIG. The same reference numerals are given to the same parts as in the conventional device.

4.4 is a disk-shaped magnetic pole plate attached to the opposing surface of the permanent magnet 1.1, and as shown in FIG. 3, a taper 4a is formed on the outer circumferential portion of the magnetic pole plate. Further, this magnetic pole plate 4 has bolts 81 and 82 extending left and right from its outer periphery, and a bolt B3 extending back and forth.

B4 is fixed @.

Reference numeral 5 denotes a metal fitting for attaching a magnetic pole plate made of a non-magnetic material (for example, stainless steel) and installed on the outer periphery of the permanent magnet 1. In this magnetic pole plate mounting, the metal fitting 5 has a cylindrical shape with four bolt support parts 5a protruding from its upper surface, and the support parts 5a have the above-mentioned vi1
Elongated holes 5b are provided through which bolts B1, B2, 83, and 84 of the electrode plate 4 are inserted, respectively. The elongated hole 5b is connected to the m-electrode plate 4.
The bolts are formed in a direction perpendicular to the axial direction of each bolt to allow longitudinal and lateral movement. Reference numeral 6 denotes a nut screwed onto a bolt inserted into the elongated hole 5b, and the magnetic pole plate 4 is attached to the metal fitting 5 by means of this nut 6.

The magnetic pole plate is attached to the metal fitting 5 using the bolts B1, 82, and B3 as shown in FIG.

Similar to B4, bolts 7 extending in all directions and bolts 8 extending downward (only one of them is shown) are fixed.

A bolt 7 is inserted through the yoke 3, and an elongated hole that allows the vertical movement of the metal fitting 5 for mounting the magnetic pole plate and a hole 10 through which the bolt 8 is inserted are formed. Reference numeral 11 denotes a nut screwed onto a bolt 7.8 inserted through the long hole 9 and hole 10, and the metal fitting 5 is attached to the yoke 3 by means of this nut 11.

The device described above adjusts the horizontal position of the magnetic pole plate 4 by rotating the nuts of the bolts 81 and B2, and adjusts the horizontal position of the magnetic pole plate 4 by rotating the nuts of the bolts B3 and Ba.
The forward and backward position of the electrode plate 4 can be adjusted, and by rotating the nut of the bolt 8, the m electrode plate 4 can be moved up and down.

Therefore, in order to set the position of the magnetic pole plate 4, first loosen the nut of the bolt 7.8 and adjust the left and right positions after ¥Iη, then tighten the bolt 8 to move the magnetic pole plate 4 to the magnet 1. After tightening the nuts of the bolts 7, inject adhesive or the like between the bolts and the nuts to fix them so that they do not come loose after adjustment.

Although one embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to the above embodiment, and can be modified as appropriate within the scope of the gist of the present invention.

[Effects of the Invention] As detailed above, according to the present invention, since the magnetic pole plate is supported so as to be movable back and forth and left and right, the mounting position of the magnetic pole plate can be freely adjusted, and therefore, the upper and lower magnetic poles can be easily adjusted. Center alignment and magnetic field uniformity adjustment is possible.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view showing an embodiment of the magnetic field generator with magnetic pole position adjustment according to the present invention, FIG. 2 is a view taken along line A-A in FIG. 1, and FIG. A plan view and a front view of the plate, FIG. 4 is a partially enlarged view of FIG. 1, and FIG. 5 is a front sectional view of the conventional device. 1... Permanent magnet, 3... Yoke, 4... magnetic pole plate,
5... Use metal fittings to attach the magnetic pole plate. ―ku~ Condolence Figure 3 Figure 4 ■ Figure 5

Claims (3)

[Claims] (1) A magnetic field that is composed of permanent magnets arranged to face each other, magnetic pole plates provided on opposing surfaces of these permanent magnets, and a yoke that magnetically couples the permanent magnets, and generates a magnetic field between the magnetic pole plates. A magnetic field generating device with magnetic pole position adjustment, characterized in that the magnetic pole plate is supported so as to be movable back and forth, right and left. (2) The magnetic field generating device with magnetic pole position adjustment according to claim 1, wherein the magnetic pole plate is attached to a magnetic pole plate mounting bracket made of a non-magnetic material and installed on the outer periphery of a permanent magnet. (3) Bolts that extend forward and backward and bolts that extend left and right are fixed to the magnetic pole plate, and the magnetic pole plate mounting bracket is provided with elongated holes through which these bolts are inserted, and the bolts inserted into the elongated holes are 3. The magnetic field generating device with magnetic pole position adjustment according to claim 2, wherein the magnetic pole plate is attached to the magnetic pole plate mounting fitting by screwing together a nut.