JPS6285411A - Cooling structure of normal conductive magnet for nmr imaging apparatus - Google Patents

Abstract

PURPOSE:To shorten a working time by buying a nonmagnetic metal without thermal working in a gap between a cooling plate groove and a water pipe to completely bury between the groove and the pipe, thereby reducing a thermal resistance and improving the operating efficiency. CONSTITUTION:Four coils 5 are placed on a trestle 4 for forming a body supporting frame, and cooling plates 6 are respectively attached to the sides of the coils 4 by bonding materials 7. A nonmagnetic metal such as stainless steel or aluminum is normally used for the plates 6, and a water pipe 6b is buried in the groove of the cooling plate. The grooves of the plate is dug so that a sectional shape becomes a square, the water pipe is disposed in the groove, a mold punching material capable of containing a cooling tube in the center of U-shaped section made of soft high thermal conductive material is press-fitted to the groove to enhance the heat transmission property of the cooling tube and the cooling plate.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an NMR imaging device, and particularly to an NMR imaging device.
The present invention relates to a cooling structure for a normal conducting magnet for an R imaging device.

[Background of the invention]

In general, a normal conducting magnet for an NMR imaging device is comprised of a coil that generates a uniform magnetic field, a power source that excites the coil, and a cooling mechanism that removes the heat generated by the coil.

The indirect cooling mechanism, which is one type of cooling tank, requires water piping, a cooling plate for supporting the water piping, and a bonding material for bonding the cooling plate and the coil. Water pipes are generally embedded in grooves cut into the cooling plate.

Methods for embedding water pipes in the cooling plate grooves include pouring molten solder into the gap between the grooves and the water pipes, or silver brazing, as shown in FIGS. 12 and 13. However, this method requires applying sufficient heat to the cooling plate, which is technically difficult for cooling plates that have a large heat capacity and a large heat dissipation effect. Also, in the case of the method of pouring solder, if sufficient heat is not applied, the solder will not flow deep into the groove, leaving a cavity inside and causing poor heat transfer between the cooling plate and the water pipe. become. Furthermore, the addition of heat causes deformation of the cooling plate and water piping, resulting in poor workability and the occurrence of defects. Furthermore, since the water piping must be buried over a long section, the heat must be dissipated after the work is completed before the next work can be started, which increases the time required for the work. In addition, because the molten solder solidifies in a shape that swells outside the groove,
If the grooved surface of the cooling plate is not flat and the coil and cooling plate are bonded using a bonding material, there is a risk that the cooling plate and coil may come into contact in the worst case scenario.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cooling structure for a normal conductive magnet for an NMR imaging apparatus, which can easily and efficiently exhaust heat.

[Summary of the invention]

The present invention completely fills the gap between the cooling plate groove and the water piping by embedding a non-magnetic metal in the gap between the cooling plate groove and the water piping without performing any thermal processing, thereby lowering the thermal resistance and improving the workability. The aim is to improve efficiency and shorten the time required for one operation.

That is, the present invention relates to an electromagnet for a diagnostic device that obtains a tomographic image of a living body using a nuclear magnetic resonance phenomenon, which includes a sheet-wound coil made of a normally conducting coil material and a disk-shaped cooling plate embedded in a cooling tube. In the coil cooling structure in which the cooling plate is attached to the side surface of the coil via a highly thermally conductive bonding material, a groove in the cooling plate is dug so that the cross-sectional shape is square, and water piping is arranged in the groove. By press-fitting a die-cut material made of a soft, high heat conductive material with a U-shaped cross section and capable of storing a cooling pipe in the center into the groove, the connection between the cooling pipe and the cooling plate is created. It is characterized by improved heat conductivity.

[Embodiments of the invention]

Examples of the present invention will be described below.

FIG. 1 shows the basic configuration of a normal conducting magnet system of an NMR imaging apparatus. In other words, the entire normal conducting magnet system consists of a magnet body 1 that generates a uniform magnetic field and a magnet body 1 that generates a uniform magnetic field.
It consists of three components: a power source 2 that excites the magnet, and a heat exchanger 3 that absorbs the heat generated by the magnet body 1.

In FIG. 2, the structure of the magnet body 1 is shown. Four coils 5 are mounted on a pedestal 4 forming a main body support frame, and cooling plates 6 are bonded to the side surfaces of each of the four coils 5 with a bonding material 7.

In FIG. 3, the configuration of the cooling plate 6 is shown. A non-magnetic metal such as stainless steel or aluminum is normally used for the cooling plate 6, and a plurality of metals 8 that are easily plastically deformed, such as water distribution solder or buttons, are prepared in the cooling plate groove 6a. Also, the cooling plate 6
In this case, grooves are cut as shown in Figs. 5, 6, 7, and 8. When cutting a groove as shown in Figure 5, it is better to roughen the sides of the groove.This is to prevent the press-fitted metal from coming off when press-fitting metal as described later. This is to ensure complete contact.

In FIG. 6, knurling is shown on the side surface of the groove for this purpose. Based on the same idea, FIG. 7 shows a cooling plate groove 8 having a reverse taper, and FIG. 8 shows a cooling plate groove 8 having sawtooth protrusions. The water pipe 6b is a non-magnetic metal pipe that does not cause deformation when metal is press-fitted.
For example, use a steel pipe. Therefore, as shown in FIG. 9, a metal 8 is set in the cooling plate groove 6a, and a water pipe 6b is placed on top of the metal 8.
, and then cover with metal 11.

Thereafter, as shown in FIG. 10, it is necessary to calculate the amount of metal 8 in advance so that the metal 8 does not protrude.

In the embodiment described above, the metal 8 shown in FIG. 4 is used, but as shown in FIG. A method of filling the gap and pressing may also be used.

In addition, powdered non-magnetic metal 11 is packed in the gap between cooling plate groove 6a and water pipe 6b instead of cotton-like or net-like non-magnetic metal 9, and resin 10 is injected until it overflows from the groove. A solidification method may also be used.

〔Effect of the invention〕

As explained below, according to the present invention, it is possible to make the heat conductivity between the cooling plate and the water piping similar to that of clay by easy processing. As a result, N
Since it is possible to realize a normal conductive magnet system for M I<image conductor equipment, the rate at which the heat generated by the magnet body is taken away by air conditioning equipment, etc. is lowered, so it is possible to reduce the running cost by that amount.

In addition, there is an effect that a normal conductive magnet system 11 can be realized with less heat accumulated in the magnet body and a quick q-chip.

Additionally, since no heat is used, workability can be improved and work time can be shortened. In addition, there is no need to worry about deformation due to heat.
It is possible to reduce the probability of defects occurring.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the normal conducting magnet system of the NMR imaging device, Fig. 2 is a side view as an example of the normal conducting magnet main body, Fig. 3 is a plan view as an example of the cooling plate, and Fig. 4 is a block diagram of the normal conducting magnet system of the NMR imaging device.
The figure is a perspective view of members used in one embodiment of the present invention, FIG. 5 is a partial vertical sectional view of a cooling plate in one embodiment of the present invention, and FIGS. A partial vertical sectional view of a cooling plate in another embodiment, FIGS. 9 and 10 are partial vertical sectional views of a cooling plate showing an example of steps in carrying out the present invention, and FIG. 11 is a partial longitudinal sectional view of a cooling plate in another embodiment. FIGS. 12 and 13 are partial vertical cross-sectional views of the cooling plate in this embodiment, and are views showing conventional cooling plates. DESCRIPTION OF SYMBOLS 1...Normal conducting magnet main body, 2...Power supply,; 3...Heat exchanger, 4...Base, 5...Coil, 6...Cooling plate,
7... Bonding material, 6a... Cooling plate groove, 6 b... Water piping, 8... Metal that is easily plastically deformable, 9... Cotton-like, net-like metal, 10... Liquid resin.

Claims (1)

[Claims] 1. NMR that obtains tomographic images of living organisms using nuclear magnetic resonance phenomena
An electromagnet for an imaging device comprising a sheet-wound coil using a normal conductive coil material and a disk-shaped cooling plate embedded with a cooling pipe attached to the side surface of the coil via a highly thermally conductive bonding material, forming a groove with a rectangular cross section in the upper cooling plate, and fitting a water conduit into the groove;
1. A cooling structure for a normal conductive magnet for an NMR imaging apparatus, characterized in that a member made of a soft, highly thermally conductive material and having a U-shaped cross section is tightly fitted into the groove.