JPS6219282B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is applicable to ferrules for optical connectors, sliders for three-dimensional measuring instruments, pen tips for ball-point pens, etc. The present invention relates to a rubber press molding method that can mold ceramic molded bodies.

[Prior art and its problems]

Conventionally, there is a method for manufacturing ceramic pipes as disclosed in Japanese Patent Publication No. 43-2444.

In this prior art, as shown in FIG.
00 extruded into an extruded base 300, and then the molded product is fired,
A ceramic pipe is formed by eliminating the wire 200.

However, ceramic molded bodies having fine holes inside can be used for various objects having different external shapes, and the above-mentioned prior art cannot mold these objects.

Therefore, the present inventors focused on the rubber press molding method, and conducted repeated studies to form press molded bodies that have fine holes in common but have different external shapes.

As a result, the necessary number of combustible core wires were stretched on a cuttable jig, and this jig was set in a rubber press mold before the pressing process, and after press forming, the press-formed product was molded together with the jig into the desired shape. It has been found that it is sufficient to add a mold making process to cut into a shape (a shape slightly larger than the target object) and perform finishing processing such as grinding after firing, leading to the present invention.

[Technical issues]

The technical problem of the present invention is to set a cuttable jig on which the required number of combustible core wires are stretched in a rubber press mold in order to form various press-formed products having minute holes and different external shapes. The process is provided as a pre-process to the pressing process, and the mold-making process for cutting the press-formed product into a desired shape together with a jig is provided as a pre-process to the firing process.

[Technical means]

The technical means of the present invention provides a cuttable jig that is formed by fixing leg pieces at appropriate intervals between the circumferential ends of opposing surfaces of a horizontal bottom plate and a top plate. A core wire tensioning process in which the combustible core wire is stretched across the board as necessary, a setting process in which the jig with the core wire manufactured in the above process is placed on the upper surface of the lower rubber mold of the rubber press mold, and each core wire is A pressing process in which ceramic powder is filled in between and pressed, a molding process in which the press-formed product is cut into a desired shape with a jig, and a firing process in which the press-formed product is fired to burn out the core wire. The process is to be carried out one after another.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

Rubber press mold A consists of a cylindrical rubber mold a, upper and lower rubber molds a' and a'' that cover the upper and lower openings of the rubber body mold a, and a metal cylinder provided around the outer periphery of the rubber body mold a. consisting of a, a, a′, a″,
A is formed by combining the metal cylinders A, and presses the powder C to be filled into the filling chamber 1 with isostatic pressure through the pressure injection port 2 opened in the metal cylinder A. A jig 3 holding a flammable core wire B under tension is provided in the filling chamber 1 (FIG. 1).

The combustible core wire B has an extremely small diameter corresponding to the diameter of the fine through hole b to be formed, for example, in microns.
The diameter is on the order of 100 microns, and a material that disappears by firing, such as nylon fishing line, is used.

As shown in FIG. 5, the jig 3 fixes the leg pieces 3' at appropriate intervals between the opposing circumferential ends of the top plate 3'' and the bottom plate 3, each having an appropriate number of suspension holes 4 drilled therein. A cuttable piece (made of wood or synthetic resin) formed by By constructing and fixing the required number of combustible core wires B in a tension manner, the combustible core wire B is stretched,
This jig 3 is attached to the lower rubber mold in rubber press mold A.
A'' is placed on the upper surface and inserted into the filling chamber 1, filled with powder C for pressing, and pressed (Fig. 2).

The powder C for pressing is, for example, ceramic powder such as alumina mixed with a binder and the like.

A press-formed product D is formed in the rubber press die A after the press-forming, and the press-formed product D is molded together with the jig 3 by slightly smaller than the desired flat, cylindrical, or hollow object. The combustible core wire A is burnt out by cutting into a large shape and firing this press-formed product D, thereby obtaining a ceramic molded product E having straight fine through holes b inside (Figs. 3 and 4). (Fig. 5).

The ceramic molded body E molded by the molding method of the present invention is subjected to finishing machining such as grinding to form ferrules for optical connectors that connect optical fibers, sliders in coordinate measuring instruments, etc.
Its use range is extremely wide, such as the nib of a ballpoint pen.

As described above, the present invention provides a step of setting a cuttable jig on which the required number of combustible core wires are stretched in a rubber press die as a pre-step of the press step, and forms a press-formed product into a desired shape (target object). As a pre-process to the firing process, we have created a mold-making process in which a jig is cut into a shape slightly larger than It is possible to provide a new and convenient molding method that can easily and simply mold sliders, ballpoint pen nibs, etc.

Thus, the intended purpose can be achieved.

[Brief explanation of the drawing]

The drawings show an embodiment of the rubber press molding method of the present invention, in which Fig. 1 is a longitudinal sectional view of a rubber press mold with a jig provided, Fig. 2 is a longitudinal sectional view of the rubber press mold during pressing, and Fig. 3 is a longitudinal sectional view of the rubber press mold during pressing. 4 is a longitudinal sectional view of a press-formed product, FIG. 4 is a longitudinal sectional view of a molded ceramic body, FIG. 5 is a perspective view of a jig, and FIG. 6 is a longitudinal sectional view of a conventional method. In addition, in the figure, A: rubber press mold, B: flammable core wire, C: powder, D: press molded product, 3: bottom plate, 3″: top plate, a″: lower rubber mold, 3′: leg piece,
3: Jig.

Claims (1)

[Claims] 1. A combustible core wire is attached across the bottom plate and top plate of a cuttable jig formed by fixing leg pieces at appropriate intervals between the peripheral edges of the opposing surfaces of the horizontal bottom plate and top plate, respectively. There is a core wire tensioning process in which the core wire is fully stretched, a setting process in which the jig with the core wire manufactured in the above process is placed on the lower rubber mold upper surface of the rubber press mold, and ceramic powder is placed between each core wire. A pressing process in which the press-formed product is filled and pressed, a molded product-forming process in which the press-formed product is cut into a desired shape with a jig, and a firing process in which the press-formed product is fired to burn out the core wire are successively carried out. A method for molding a ceramic molded body having micropores, characterized by: