JPS5841375A - Manufacture of honey comb construction with unidirectional focus - Google Patents

Abstract

PURPOSE:To provide a method for making a distortion-free block for a collimator having a focus line by fixing an angular relationship between tube materials with the injection of an appropriate anchor members therebetween. CONSTITUTION:A composite strand hexagonal in the cross-section covered with a lead alloy or the like is cut to an appropriate length. Raw materials 4 thus formed are supported at the lower end thereof on a base material 6 in a partially tapered die 5 while bundled aligned with the parallel sections thereof. The base material 6 is forced long the parallel sections of the die 5 to make the raw materials 4 free at the upper end while remains almost fixed at the lower end. Under such a condition, they are expanded in a sector at the upper end thereof 4 in the direction of X, one of the apexes of the hexagonal cross-section of the raw material by inserting a spacer 10. Subsequently, an appropriate adhesive is injected and solidified in the die 5 so that the materials are joined together to form product like a block, whic is taken out of the die 5. The product is cut off at the lines (a) and (b) to make a block level at the upper and lower surface.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a fine honeycomb structure of a collimator used, for example, with a scintillation camera, and more particularly to a method for manufacturing a honeycomb structure having a unidirectional focus.

A collimator for a scintillation camera is used to pass only radiation emitted from spatially distributed radioactive isotopes in a desired direction, and in general, the collimator is a collimator that is opaque to the radiation, such as specific gravity and atomic number. It is formed by using a large material, especially a block of lead or lead alloy from the point of view of ease of processing and economy, and providing fine straight holes in it. It is extremely difficult to create fine holes uniformly and densely by machining, so they are formed by metallurgically joining corrugated lead or lead alloy plates of appropriate shapes, or Wire rods with a thin alloy plate as the outer sheath and a core material made of a material that is more easily soluble in certain chemicals, etc. are cut into appropriate lengths, tied and aligned, and adjacent wire rods are appropriately joined. It is becoming common practice to remove only the core material by appropriately dissolving it.

In any case, the pores of the honeycomb structure formed in this way are generally parallel and do not have focal points. On the other hand, it has a closest focus or focal line. Collimators consisting of honeycomb structures of the so-called converging or diverging type are required for the formation of partial magnifications, line images, degrees Celsius or tomographic images.

A method for manufacturing a honeycomb structure having such a focal point or a unidirectional focal point, that is, a focal line, is disclosed in, for example, Japanese Patent Application Laid-Open No. 52-13.
5872. In the manufacturing method disclosed by JP-A-Sho, the block of the non-nikum structure having parallel holes formed as described above before the core material is melted and removed is placed in an appropriate mold jig, and It is pressurized to plastically deform it, and after cutting, the core material is melted to form a focal point structure. Since this method uses plastic deformation of the block, there is a high possibility that uncontrollable distortion will be introduced, and therefore the reliability of the performance of the collimator obtained in °C is low.

Another conventional method for manufacturing a focused honeycomb structure is disclosed in Japanese Patent Application Laid-open No. 5
5-7672 and 55-97949. The method shown in Japanese Patent Application Laid-open No. 55-7672 uses a batten with alignment holes and a guide pin passing through the alignment holes to fix one end of the wire rod to a tapered jig with an open upper part. After oriented in the jig so as to converge on the focal point, the direction is fixed with epoxy resin to form a block, and then the stone is melted.

Although this method is effective, the process of orienting the wire with guide pins is relatively difficult. Also, JP-A-55-97
According to the technique shown in No. 949, the open end side of a wire bundle placed in a taper jig in the same manner as above is brought into contact with one side of a membrane made of an elastic material such as rubber, and then this Pressure is applied from the other side of the membrane material to expand and deform the membrane material, thereby expanding and fixing the open end side, and after removing the core material, it is cut to create a flat surface, but this method has uncontrollable problems. There is a high possibility that distortion will occur, which is a practical problem. Furthermore, in a honeycomb structure with a unidirectional focus, it is extremely important for scanning when used in a scintillation camera that the honeycomb rows have linearity in the direction where the honeycomb structure does not have a focus.

An object of the present invention is to achieve excellent linearity in the non-focal direction by using a relatively simple process. Moreover, it is an object of the present invention to provide a method for manufacturing a honeycomb structure for a collimator having a focal line without distortion.

The present invention will be described in detail below based on the drawings.

From the viewpoint of uniformity and linearity of the resulting collimator sensitivity, a cylinder having a sufficiently small lead wall thickness and a hexagonal cross section is highly desirable. Therefore, the article JP-A No. 52-13387
A wire material having a lead or lead alloy outer sheath disclosed in No. 2 and a regular hexagonal cross section with aluminum as the core material is used.

FIG. 1 is a sectional view illustrating the first stage in an embodiment of the present invention. In FIG. 1, a material 4, which is formed by cutting a hexagonal cross-section composite wire having a lead or lead alloy outer sheath to an appropriate length, is placed in a partially tapered mold 5, and its lower end is placed on a base material 6. While supporting, the parallel portions are aligned and focused so as to have the mutual positional relationship shown in FIG.

Next, as shown in FIG. 2, the base material 6 is advanced into the parallel part of the mold 5, so that although the lower end of the material 4 is almost fixed, its upper end becomes free. In this state, as shown in FIG. 6, the upper end of the material 4 is expanded into a fan shape in the X direction, which is the direction of one vertex in the hexagonal cross section of the material, by means of a flattener 10. This state at the upper end surface portion of the mold is shown in FIG.

In this case, it will be obvious to those skilled in the art to suitably choose the dimensional relationships of the spacers 10 in order to achieve the desired focus position and uniform spread between the materials 4.

After creating an appropriate space between the materials 4 in this way, a suitable adhesive such as epoxy resin is injected into the mold 5 and solidified to join the materials together, and the mold 5 is also taken out as a block. , for example, at lines α and b shown as dotted lines in FIG.
The top and bottom surfaces of this block are cut to make them flat. The upper surface obtained by cutting is shown in FIG. The bottom surface is the 6th
Approximately equal to the figure.

Next, this block is immersed in an alkaline solution 1, such as an aqueous caustic soda solution, to dissolve the aluminum, which is the stone material, to obtain the desired honeycomb structure with a one-way focus.

In the above embodiments, a composite wire has been described, but as mentioned above, the present invention is not limited to this, and similar results can be obtained even if a thin tube is used.

As described above, according to the present invention, although the process itself is very simple, it is possible to manufacture a unidirectional focused honeycomb structure with high precision and a fine structure, which is extremely advantageous industrially. It is something.

[Brief explanation of drawings]

Claims (1)

[Claims] 1. Place one end of a tightly focused bundle of a plurality of thin tubular materials having a hexagonal cross section in a taper jig with the other end fixed and the other end free, and place the other end of the bundle into two opposing ends of the hexagonal cross sections While keeping the surfaces in contact with each other, use a spacer to expand the tube so that it is parallel to the surface and at equal angular intervals in the direction connecting the two opposing vertices, and inject an appropriate filling and fixing material between the tube materials. A method for producing a honeycomb structure with a unidirectional focus, which comprises forming a block with a fixed angular relationship, removing a taper jig, and cutting the upper and lower ends of the block to make them flat.