JPS6322961B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a molding machine for extrusion molding a small diameter pipe. 2. Description of the Related Art There is a conventional micro-hole pipe forming machine shown in FIGS. 1 to 3. Fig. 1 is a side sectional view of the molding device, Fig. 2 is a front view of the same, and Fig. 3 is a rear view of the same, showing the back of the pin holder 2 where the pin 1 that determines the inner diameter of the pipe is held at the tip. The end portion is fixed to a pin holder fixing ring 4 by a fixing nut 3. The base 5 has a peripheral part that fits into the peripheral part of the pin holder fixing ring 4, and its inner wall is separated from the outer wall of the pin holder 2, and the tip part has a hole into which the pin 1 is fitted and inserted. 6. The pin holder fixing ring 4 is provided with three gaps 7, as shown in FIG.

In the micro-hole pipe forming machine having such a configuration, after the pin holder fixing ring 4 and the base 5 are fitted together, from the gap 7 of the pin holder fixing ring 4,
For example, by pressing ceramic compound into
The material is squeezed between the inner wall of the cap 5 and the outer wall of the pin holder 2, and the ceramic pipe whose inner diameter is determined by the pin 1 is extruded and molded from a hole 6 at the tip of the cap 5. In addition to ceramics, thermoplastic resins such as acrylic and polycarbonate are used as the kneading material.

In general, micro-hole pipe forming machines require precision concentricity between the pin 1 and the hole 6 of the cap 5. That is, the pin 1 must be concentrically held straight by the pin holder 2, and the pin holder 2 must be concentrically fixed to the base 5.

Conventionally, in order to hold pin 1 at the tip of pin holder 2, a hole is first drilled in the center of the tip of pin holder 2 using a micro drill, and then pin 1 is inserted into the drilled hole and fixed with adhesive. That's what I was doing. However, when the pin diameter is as small as 0.15 mm, the hole depth can only be made as shallow as 0.3 to 0.5 mm using the above-mentioned micro drill, and the drill runs out, causing the pin to become too small. It was also difficult to improve the accuracy with respect to the center of the holder 2.

Therefore, in a molding machine with a conventional configuration,
Since the hole in the pin holder that holds the pin is shallow, it is difficult to stand the pin perpendicularly to the end surface of the pin holder, and the tip of the pin that is inserted into the hole in the cap tends to deviate greatly from the axis. Further, since the hole in the pin holder is shallow, there is a small area for holding the pin, and the holding force is weak, so that the pin sometimes comes off during extrusion of the mixed material. Furthermore, because of the above-described escape of the microdrill, the pin could not be fixed coaxially to the pin holder, and it was difficult to coaxially hold the pin in the hole of the cap.

The present invention was made in view of the above-mentioned problems, and it is possible to process the pin holder by embedding a pipe that is sufficiently thicker than the pin diameter with good concentricity between the micro hole and the outer diameter at the tip of the pin holder. To provide a micro-hole pipe forming machine which can enlarge the diameter of the hole to be formed, can perform deep hole processing and good coaxiality of drilling, and can hold a pin coaxially in the opening of a mouthpiece. With the goal.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 4 is a side sectional view showing one embodiment of the present invention. The pin 11 that determines the inner diameter of the pipe is a pin holding pipe 12 made of ceramic or ultra-high quality sintered metal.
pin holding pipe 1.
2 is press-fitted into the tip of the pin holder 13. The pin holding pipe 12 has already been machined with minute holes with high precision, and the holding area and holding length of the pin 11 are made sufficiently large. Since the pin holding pipe 12 is a through hole, the pipe material is first manufactured by extrusion molding or rotary swaging, and then the dimensional accuracy and concentricity of the hole diameter are improved by wire wrapping or centerless grinding with wire guided sliding. Since it can be processed, high-precision products can be easily obtained. The pin holder 13 has a hollow hole 1 that communicates coaxially with the hole 14 into which the pin holding pipe 12 is press-fitted, and extends to the rear end.
5 is formed, and a cap 16 is fitted to the end of the hollow hole 15. Further, the pin holder 13 is made of an integrally molded body of a conical part 13a on the side into which the pin holding pipe 12 is press-fitted and a disc-shaped part 13b on the side into which the cap 16 is fitted. As shown in FIG. 1, three gaps 17 are formed in 13b for pushing a kneaded material made of ceramic, acrylic, thermoplastic resin such as polycarbonate, or the like. on the other hand,
The cap 19, which has an opening 18 at its tip through which the pin 11 is inserted, is connected to the conical portion 13a of the pin holder 13.
A main body part 19a having a mortar-shaped inner wall spaced apart from the outer wall of the main body part 19a, and a fixing part 19b integrally formed at the rear end thereof.
This fixing part 19b is made up of pin holder 1.
It is adapted to be fixed to the peripheral edge of the disc-shaped portion 13b of No. 3.

Figures 5a and 5b are a side sectional view and a front view showing the main parts of the above embodiment. In this embodiment, the length of the pin holding pipe 12 is approximately 30 times the diameter r of the pin 11, the concentricity between the outer diameter and the inner diameter of the pin holding pipe 12 is 3 μm or less, and the pin 11 and the pin holding pipe 12 are The clearance is finished to less than 2μm. Pin holding pipe 12 of pin holder 13
The fitting part 20 is internally ground, honed,
The pin retaining pipe 12 and the pin holder 13 are assembled in a tight fit, fully finished with a wrap. By doing so, the pin 11 can be sufficiently held in the pin holding pipe 12 parallel to and concentrically with the axis.

Further, by loosely fitting the cap 19 and the pin holder 13 with a clearance of 5 μm or less, the concentricity between the pin 11 and the opening 18 of the cap 19 could be maintained at 10 μm or less at the maximum.

In the above embodiment, the pin holder 13 is an integrally molded body consisting of the conical part 13a and the disc-shaped part 13b, but it is also possible to separate these parts and combine them with a nut or the like.

As described above, according to this embodiment, the long pin holding pipe 12 with a diameter thicker than that of the pin 11 is fixed to the pin holder 13.
The hole drilling process in step 3 can sufficiently ensure coaxiality and axis parallelism, and the pin 11 can also be inserted deeply into the pin holding pipe 12 and stand perpendicular to the end surface of the pin holder 13, and the holding area of the pin 11 can also be reduced. It is large and has strong holding power, so the pin 11 will not come out.

Furthermore, according to this embodiment, the pin holder 13
Since a hollow hole 15 is formed in the pin 11, by removing the adhesive holding the pin 11 in the pin holding pipe 12 by cleaning with a solvent, the pin 11 can be stored in the hollow hole 15 in the event that the pin 11 is broken. It is possible to use the pins 11 by sequentially drawing them out.

As explained above, according to the present invention, by embedding a pin holding pipe with good concentricity between the microhole and the outer diameter in the tip of the pin holder, the diameter of the hole machined into the pin holder can be increased, and Enables deep hole machining with good coaxiality, reaming and reaming after machining the pilot hole.
Various concentric finishing operations such as internal grinding, honing, and lapping can be easily performed, and the pin can be held concentrically in the pin holder via the pin retaining pipe, resulting in the pin being coaxial and concentric with the opening of the base. It can be held accurately and with strong holding force.

[Brief explanation of the drawing]

1, 2, and 3 are side sectional views, front views, and rear views of a conventional micro-hole pipe forming device, respectively, and FIG. 4 is a side view showing an embodiment of the micro-hole pipe forming device of the present invention. The sectional view and FIGS. 5a and 5b are a side sectional view and a front view of the main part of the same embodiment. 11...Pin, 12...Pin holding pipe, 13
... Pin holder, 15 ... Hollow hole, 16 ... Cap, 17 ... Gap, 18 ... Hole, 19 ...
Base.

Claims (1)

[Scope of Claims] 1. A pin holding pipe that concentrically penetrates and holds a micro-diameter pin that determines the inner diameter of the pipe, and a gap in which the pin holding pipe is buried in one end and a kneaded material is pushed into the other end. a pin holder, and a cap that faces the pin holder and has an opening at one end of the pin holder through which a small diameter pin is inserted concentrically, and is coupled to the pin holder at the other end of the pin holder. , a micro-hole pipe molding comprising: a connecting path provided between the cap and the pin holder so as to connect the opening and the gap; and molding the micro-hole pipe by extrusion molding. vessel. 2. The micro-hole pipe forming machine according to claim 1, wherein the micro-diameter pin penetrated and held by the pin holding pipe extends into a hollow hole provided in the pin holder.