JPS60161116A - Manufacture of rubber or resin bent pipe joint - Google Patents

Abstract

PURPOSE:To mold a resin product with no flash developed on the inside surface of a bent pipe by a method wherein a flexible sealing member is fitted on the joining portion of a pair of cores, both of which are arranged within a mold, in order to prevent resin from penetrating into the bent position in the joining portion of a pair of the cores. CONSTITUTION:The tip of one core 3 is fitted in the hole 22 of the other core 2 in order for the cores 2 and 3 to abut against each other at right angles in a mold 1. At this time, a flexible sealing member 4 is fitted onto the tip of the core 3 and tightly contacts to the inside surface of the opposing hole 22 by being elastically deformed simultaneously with the insertion of the tip of the core 3. Resin is filled under pressure in a cavity formed between the mold 1 and the cores 2 and 3. Because the abutted portion of the cores 2 and 3 is sealed by the sealing member 4, no resin material flows in the innermost recess of the hole 22. After the solidification of the resin, a pipe joint 6 is obtained by opening the mold and removing the cores by drawing. No flash develops at all in the inside surface of the pipe, because no resin material penetrates into the hole 22.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a bent pipe joint made of rubber or resin.

Conventionally, as shown in Fig. 4, a pair of center cores +21 +3) are connected to one center core (2) by removably fitting the tip of the other center core (3) into a receiver (22) opened in one center core (2). Core +21 +3
1 are butted at right angles in the mold (1), and a cavity (5) is formed between the mold (1) and the cores +21 +31.
The tube joint (6) shown in FIG. 5 is manufactured by filling the tube with material, opening the mold, and drawing out the core +2) (3).

However, when filling the cavity (5) with this material,
The material enters through the slight gap between the receiver [F] 2) and the tip of the center core fitted into the receiver (2), and the material fills to the depths of the hole @, resulting in the center core +2) +3). Even if it is removed, the hole (6) of the pipe joint (6) in which the material filled in the depth of the receiver
It remains in υ and blocks the child 611.

If the inside of the pipe joint (6) is blocked as described above, it cannot be used as a fluid joint, and the blocked part must be torn off, which is time-consuming, and it is difficult to completely tear off the blocked part. It was difficult to remove, and there were problems such as the remaining portion acting as resistance to the fluid flowing through the joint.

[Purpose] An object of the present invention is to prevent material from entering the receiver from the abutting portion of the core, and to solve the above-mentioned problem caused by blocking the inside of the pipe with the material.

〔composition〕

The molding procedure is the same as before, but a ring-shaped M with good mold releasability for the joint material is used at the abutting part of both cores.
The SS pourable sealing member 4) is interposed to prevent material from entering the recipient @, and the sealing member (4) is inserted at the same time as the core is extracted.
4) Extract.

[Action and effect]

The sealing material reliably prevents material from entering the gap between the receiving hole and the tip of the core fitted into the receiving hole, so the pipe will not be blocked by material entering the hole as in the past. There isn't.

In addition, since the sealing member has good releasability with respect to the material, the sealing member does not adhere to the pipe joint, and the sealing material can be taken out after being fitted in the center, making it possible to efficiently manufacture the pipe joint.

The present invention will be specifically described below based on embodiments shown in the drawings.

Fig. 2 shows an L-shaped pipe joint (6) manufactured according to the present invention, and inside the joint (6) there is a stepped portion ((to) (6) that serves as a stopper for the mating pipe [71+81] to be connected.
41 is formed.

The above joint (6) has a pair of center cores t21 as shown in Figure 1.
+3+ are butted at right angles in the split mold (1), and the mold (
It is formed by filling a cavity (5) formed between the core (1) and the core (2) (t3) with material.

At the tip of one of the cores (2), the surface on which the mating core (3) comes into contact is formed as a flat surface 21), and a receiver @ is formed on the flat surface 211.

The distal end side of the other core (3) is formed to have a small diameter, and a circumferential groove (2) is provided at the distal end side of the small diameter shaft portion Gll. A ring-shaped flexible sealing member (4) is fitted which fits tightly into the ring.

The flexible sealing member (4) is made of a material that can be preformed well with respect to the material of the pipe joint (6) to be formed, and in the embodiment, the material of the pipe joint is EPDM, and the sealing member is made of silicone rubber or fluorocarbon rubber. It is formed of.

Then, in the mold (1), the tip of the other core (3) is fitted into the hole (2) of one core (2), and both cores t21131 are abutted at right angles.

At this time, the flexible sealing member (4) attached to the tip of the core (3) is elastically deformed and comes into close contact with the inner surface of the mating hole &2).

A material is pressurized and filled into a cavity (5) formed between the mold (1) and the core +2+ +31.

The material has a gap in every corner of the cavity (it is filled, but the center core + 2) (At the butt part of 3+, the sole member (4) completely seals the gap between the hole (2) and the shaft tip. Therefore, the material is completely prevented from flowing into the depths of the hole.

After the resin in the cavity hardens, the mold is opened and the core is removed to obtain a pipe joint (6).

The ring-shaped seal member (4) is made of a material that is releasable from the material of the pipe joint.
) does not adhere to the bone joint (when removing the core, the sealing member (4) is inserted into the circumferential groove of the core (3) and is removed, leaving only the sealing member (4)). It saves you the trouble of taking it out.

Figure 3 shows that the small diameter shaft G on the tip side of one center core (3) is tightly fitted with the seal member (4), and the seal member (4) is attached to the receiver (2) of the mating core (2). This figure shows another embodiment in which the material is tightly applied to the edge of the opening to prevent material from entering the receiving cavity.

It should be noted that the present invention is not limited to the above-mentioned cross-shaped pipe joint, but can of course be applied to the manufacture of T-shaped pipe joints.

[Brief explanation of drawings]

Fig. 1 is a sectional view of the main parts of the mold and core, Fig. 2 is an oblique view of the pipe joint, Fig. 3 is a sectional view of another embodiment, Fig. 4 is a sectional view of the conventional example, and Fig. 5 is a sectional view of the main part of the mold and core. The figure is a sectional view of a conventional pipe joint. (1)... Mold +2+ +31... Core ■...
Socket hole diagram 4

Claims (1)

[Scope of Claims] ■ A pair of center cores +21 and +31 are removably fitted into the receiving openings provided in one center core (2), and the tips of the other center core (3) are removably inserted into the mold (1). Butt at right angles, center core +2+
In a method of manufacturing a bent pipe joint by filling a cavity formed between +31 and a mold (1) with a rubber or resin material, opening the mold, and extracting a core, the joint to be formed. By interposing a ring-shaped flexible ring member (4) with good releasability against the material at the abutting portion of both cores (21131), the material can be prevented from entering the receiver (22). A method for manufacturing a bent pipe joint made of rubber or resin, characterized by: ■ A circumferential groove T321 is provided at the tip of the core (3) that fits into the receiver (221), and a flexible seal is provided in the circumferential groove L32. A method for manufacturing a bent pipe joint made of rubber or resin according to claim 1, in which the member (4) is fitted.