JPS5839045B2 - Kantsugi Tenno Seizou Sochi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for manufacturing a synthetic resin pipe joint having a groove for a seal ring device on the inner circumferential surface of the end portion.

Synthetic resin pipe fittings are processed from synthetic resin pipes and molded using injection molding, but the injection molding method allows for the production of large quantities of the same type of resin pipe fittings. However, when manufacturing a molded product that has a relatively deep undercut over the entire inner circumference of a cylindrical product, such as a synthetic resin pipe joint that has a groove for a seal ring device on the inner peripheral surface of the end, In order to separate the core of the mold from the molded product, the manufacturing mold requires an extremely complicated mechanism, which is expensive, and also has the disadvantage of being complicated and prone to failure.

This invention was made in view of the diagonal point,
To provide a manufacturing device for a pipe joint having a seal ring mounting groove using a simple mechanism without forming a groove in post-processing.

The gist of this invention is to form a cylindrical mold cavity when closed, and to be formed of an outer mold and a core mold provided with a runner leading to the mold cavity, and to form an outer surface of the cylindrical mold cavity of the outer mold. At least one end of the inner surface shape portion is a movable member divided into a plurality of parts in the direction of the cylinder axis, the movable member is movable in a direction perpendicular to the central axis of the cylindrical mold cavity, and the core mold in the housing is a core mold. A main body and a short cylindrical auxiliary core mold slidably fitted onto the main body, the cylindrical auxiliary core mold forming an inner end of the movable member when closed, and the core mold main body A pressurized fluid passage is provided in the pipe joint manufacturing apparatus, and the passage is open at a portion where the auxiliary core mold is fitted during closing.

Next, this inventive device will be explained with reference to embodiments of the drawings.

Reference numeral 1 denotes an outer mold, which consists of a fixed mold 11 and a movable mold 12 that can be opened and closed.

2 is a core type, which includes a rod-shaped core type body 21 and this core type body 2.
It consists of a short cylindrical auxiliary core mold 22 that is slidably fitted on the outer mold 1 and the core mold 2, and a pressurized fluid passage 23 is provided in the core mold main body 21, and this fluid passage 23 is connected to the outer mold 1 and the core mold 2. It opens in the peripheral wall portion of the core mold main body 21 into which the auxiliary core mold 22 is fitted during closing.

The outer mold 1 and the core mold 2 are closed to form a cylindrical mold cavity A.

This cylindrical mold cavity A has the same shape as the pipe joint to be molded except for the connecting end. Type fossa A
It is designed to be injected into the body.

Reference numeral 4 denotes a plurality of movable members, which are connected to the outer mold 1 at the end portion of the cylindrical mold cavity A, so that the inner surface thereof forms the outer surface of the end portion of the cylindrical mold cavity. The inclined pin 5 allows reciprocating movement in a direction perpendicular to the central axis of the cylindrical mold cavity A.

The end of the tilting pin 5 is fixed to a member 6 that is movable relative to the outer mold 1.

Next, a procedure for manufacturing a pipe joint using the above apparatus will be explained.

First, mobile type 12. The core mold 2 is moved to a predetermined position, the outer mold 1 is closed, and a cylindrical mold cavity A is formed inside the outer mold 1 and the core mold 2 (FIG. 1).

Molten resin B is injected into this cylindrical mold cavity A through a runner 3 from an injection molding machine (not shown).

Subsequently, the auxiliary core mold 22 is moved in the axial direction of the core mold body 21 to separate from the molten resin B injected into a cylinder (FIG. 2).

At this time, the tip of the fluid passage 23 provided in the core body 21 is opened, and the auxiliary core 22 is moved to send pressurized fluid to the space C formed.

Thereafter, when the member 6 is moved in the same direction as the auxiliary core mold 22, the movable member 4 is moved in the direction of the central axis of the core mold body 21 in order to move the inclined pin 5 fixed to this member 6. The end of the cylindrical resin B is pressed against the outer circumferential surface of the core body 21.

As a result, the diameter of the end of the cylindrical resin B is reduced, and a concave groove V is formed on the inner circumferential surface of the end, resulting in the desired pipe fitting shape D.
(Figure 3).

Similarly, the pressurized fluid may be sent to the space C formed by moving the auxiliary core mold 22 when or after the movable member 5 is moved.

Thereafter, after cooling the cylindrical resin B, the movable mold 12 and core mold main body 21 are moved and the pipe joint is removed (FIG. 4).

After removing the pipe joint, operate in the reverse order as described above to return to the state shown in FIG. 1.

Thereafter, this operation is repeated cyclically to produce a pipe fitting.

As described above, in the device of this invention, the pressurized fluid flows out from the core mold body into the cavity formed by the movement of the auxiliary core mold, and the movable member presses the tip of the injected cylindrical body. Since the diameter of the cylindrical body is reduced, the diameter reduction action of the movable member and the action of the pressurized fluid to press the cylindrical wall of the cylindrical body outward and maintain its shape combine to cause the cylindrical body to shrink. A groove is formed along the circumferential direction on the inner circumferential surface of the end portion.

Therefore, since there is no so-called undercut mold for forming this groove, a complicated mechanism for removing such an undercut mold is not required, and an inexpensive pipe fitting device is provided. This makes it easier to manufacture pipe fittings.

[Brief explanation of drawings]

1 to 4 are cross-sectional views of the essential parts of one row of the device of the present invention. FIG. 1 shows the state in which the outer mold and the core mold are closed to form a cylindrical mold cavity, and FIG. Figure 3 shows a state in which the auxiliary core mold has retreated after resin injection, a state in which the movable member has moved toward the center of the cylindrical mold cavity, and Figure 4 shows a state in which the outer mold has opened and the core mold body has retreated. This indicates the state in which the pipe fitting is detached.
FIG. 5 is a sectional view taken along line V-V in FIG. 1. 1... Outer mold, 21... Core mold body, 22
...Auxiliary core type, 23...Fluid passage, 4
......Movable member, A'......Cylindrical mold cavity, D
・・・－・・・Pipe fitting.

Claims (1)

[Claims] 1. A core mold and an outer mold that forms a cylindrical mold cavity when closed and is provided with a runner that leads to the mold cavity, and an inner surface of the outer mold that forms the outer surface of the cylindrical mold cavity. at least one end portion thereof is a movable member divided into a plurality of parts in the direction of the cylinder axis, the movable member is movable in a direction perpendicular to the central axis of the cylindrical mold cavity, and the core mold in the housing is connected to the core mold main body. and a short cylindrical auxiliary core mold that is slidably fitted into the main body, and the short cylindrical auxiliary core mold is located inside the movable member when closed, and the inner surface end of the cylindrical mold cavity. 1. An apparatus for manufacturing a pipe joint, characterized in that the core body is provided with a pressurized fluid passage, and the passage opens at a portion where the auxiliary core mold is fitted when the auxiliary core mold is closed.