JPH04308705A - Working method of fluid passage of porous mold - Google Patents

Abstract

PURPOSE:To present a temperature controlling fluid form leaking out into a porous part, by a method wherein a through hole is formed in the right and left sides or the top and bottom sides of a porous mold by a drill, a heat conductive pipe having a comparatively small-diameter is inserted into the through-hole and the same pipe is fixed to the mold. CONSTITUTION:In the case of working of a fluid passage for flowing of a temperature controlling fluid into a porous mold 1 which possesses fine holes of not exceeding about 20mum in the whole surface and has made deareration easy, after boring of two through-holes 1B which pierce through the right and left sides into the porous mold 1 by a small-diameter (for example, 8.1mm) drill 2, both ends of the through holes 1B are bored to the extent of depths of about 20mm by a large-diameter (10.5mm) drill 3 and a through hole ports 1C are made into wide holes. Then a part of the through hole port 1C is threaded by making use of a tap, a pipe (for example, 8.0mm) 4 having favorable thermal conductivity such as one made of copper is inserted into the through hole 1B and the same is fixed by screwing on a tightening screw 5 provided with a slitting to the screw part of the through hole port 1C. An end part of the pipe 4 is connected with a fluid feed pipe.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of fabricating a fluid passageway for flowing a temperature regulating fluid into a mold having pores of 20 μm or less over its entire surface.

0002

[Prior Art and Problems] When plastic is injection molded using a conventional mold, there is a problem in that gas escape from the cavity (inside the mold) is insufficient, resulting in defects such as weld lines or gas burns in the molded product. Generally, molds are processed with pores, slits, vent plugs, etc. in order to prevent this, but molds are manufactured using mold materials that have fine pores uniformly over the entire surface. In recent years, porous molds have been increasingly used because they further improve air release and because the holes are so small that there are no slits or vent plugs. However, such a porous mold has a problem in that it is not possible to provide a fluid passage for temperature adjustment (even if it is provided, fluid will leak from the minute pores), and its range of use is limited. The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a method for easily constructing a passageway that does not leak fluid.

0003

[Means for solving the problem] In order to achieve the above object, the fluid passage construction method of a porous mold according to the present invention involves penetrating the left and right sides or the top and bottom sides of a porous mold with a drill. A through-hole is bored, a pipe with good thermal conductivity that is slightly thinner than the through-hole is press-fitted or inserted into the through-hole, and the pipe is fixed to a porous mold using various fixing methods. It is something.

0004

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described in detail below with reference to the drawings. The porous mold 1 with the cavity 1A formed on the surface has pores with an average open pore diameter of 20 μ or less uniformly provided over the entire surface, and the open porosity is 15 to 30%.
After drilling two through holes 1B penetrating the left and right sides of this porous mold 1 with a small diameter (8.1 mm) drill 2 (Fig. 1) (Fig. 2), a large diameter (10.5 mm) drill 3 Both ends of the through hole 1B are bored to a depth of about 20 mm to make the through hole opening 1C a wide hole. (Figure 2) (Figure 3). Next, use a tap to cut a thread in a part of each through-hole opening 1C, and then insert a copper or brass pipe (8.0 mm) 4 with good thermal conductivity into the through-hole 1B and slot it into the hole. It is screwed and fixed to the threaded portion of the through-hole opening 1C using the tightening screw 5 (FIG. 3) (FIG. 4). Further, both ends of each screwed pipe 4 are communicated with appropriate parts via a fluid supply pipe, a fluid discharge pipe, a communication pipe, etc., and the pipe 4 is used as a fluid passage. Therefore, since the fluid flows within the pipe 4, problems such as leakage onto the surface of the porous mold 1 do not occur. In the above embodiment, the pipe 4 is fixed by screwing with a slotted tightening screw, but it may be fixed by simply using adhesive or soldering, or by expanding and expanding the end of the pipe 4 to fit and fix it. Good too. In these cases, there is no need to enlarge or thread the through hole 1C of the through hole 1B.

[0005]

Effects of the Invention As is clear from the above description, the present invention involves drilling through holes on the left and right sides or the top and bottom sides of a porous mold, and press-fitting or inserting a pipe with good thermal conductivity into the through holes. Since the pipe is fixed in place, the temperature regulating fluid flows inside the pipe and does not leak into the porous portion, and the fluid passage can be constructed extremely easily, which has a significant effect.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram for explaining an embodiment of the present invention, showing a state before a through hole is drilled.

FIG. 2 is a schematic diagram for explaining an embodiment of the present invention, showing a state before the opening of a through hole is drilled.

FIG. 3 is a schematic diagram for explaining an embodiment of the present invention, showing a state before a pipe is inserted into a through hole.

FIG. 4 is a schematic diagram for explaining an embodiment of the present invention, showing a state in which a pipe is fixed to a porous mold.

[Explanation of symbols]

1 Porous mold 2 Drill 4 Pipe 5 Slotted tightening screw

Claims (1)

[Claims] Claim 1: A through hole 1B is drilled through the left and right sides or the top and bottom sides of the porous mold 1 using a drill 2, and the through hole 1B is heated slightly narrower than the through hole 1B. A fluid passage construction method for a porous mold, which comprises press-fitting or inserting a highly conductive pipe 4 and fixing the pipe 4 to a porous mold 1 by various fixing methods.