JP3455421B2 - Core - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an expandable / reducible diameter core which is mainly used for forming a rubber ring mounting groove in a receiving portion of a pipe joint or a drainage basin.

[0002]

BACKGROUND OF THE INVENTION For example, a groove for mounting a rubber ring for ensuring airtightness is formed in a receiving portion of a pipe joint. In order to form such a receiving part, a rubber ring mounting groove forming part is provided on the inner mold of the receiving part, but since the rubber ring mounting groove of the molded receiving part is an undercut part, the receiving port is formed. The internal mold cannot be pulled out from the receiving portion. Therefore, an expanding / contracting diameter core is arranged in the rubber ring mounting groove forming portion of the receiving part inner mold, the expanding / contracting diameter core is in an expanded state during molding, and when the inner mold is pulled out from the molded product after molding, There is provided a mold of a type in which an expanded / contracted core is stored in an inner mold in a contracted state.

[0003]

2. Description of the Related Art Conventionally, as shown in FIG.
6) is provided. The expansion / contraction diameter core (46) is an expansion / contraction diameter guide.
(47), a fan-shaped core (48), a trapezoidal core (49), the expansion and contraction diameter guide (47) has a taper shape in which the diameter decreases from the root end to the tip, and the peripheral surface has The guide dovetail groove (50) of the fan-shaped core (48) and the guide dovetail groove (51) of the trapezoidal core (49) are provided alternately, and the guide dovetail groove (50, 51) is provided with the fan-shaped core. (48)
And the T-shaped fitting portions (48A, 49A) respectively formed at the root ends of the trapezoidal cores (49) are slidably fitted. In the expanding / contracting diameter core (46) having the above-mentioned structure, the fan-shaped core (48) and the trapezoidal core (49) are located at the root end of the expanding / contracting diameter guide (47) at the time of molding. When the inner die is pulled out, slide the expansion / contraction diameter guide (47) so that the fan-shaped core (48) and the trapezoidal core (49) are at the tip of the expansion-contraction diameter guide (47). It is positioned and the reduced diameter state shown in FIG. 14 is obtained.

[0004]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the case of (46), the T-shaped fitting portions (48A, 49A) of the fan-shaped core (48) and the trapezoidal core (49) and the guide dovetail groove (50, 50) of the expansion / contraction diameter guide (47).
51) and there is some rattling between it and
As shown in Fig. 3, the fan core (48) and the trapezoid core (49) in the expanded state.
There is a problem that the circumference formed by and becomes uneven, and a rubber ring mounting groove having a smooth inner circumference cannot be obtained.

[0005]

As a means for solving the above-mentioned conventional problems, the present invention has a taper shape in which the diameter decreases from the root end to the tip, and the guide dovetail groove (10) is formed on the peripheral surface. ) And guide slopes (11) are alternately arranged, the expansion / contraction diameter guide (7), the fan-shaped core (8) with the T-shaped fitting portion (8A) formed at the root end, and the trapezoidal core (9). Consisting of the guide slope
The inclination of (11) is set to a steeper angle than the inclination of the guide dovetail groove (10), and the T-shaped fitting portion (8A) of the fan-shaped core (8) is a guide of the expansion / contraction diameter guide (7). It is slidably fitted in the dovetail groove (10),
The trapezoidal core (9) is slidably arranged on the guide slope (11), and both sides of the trapezoidal core (9) are held by both sides of the fan-shaped core (8). An insertion hole (13) for inserting the overhanging rod (12) is formed between the trapezoidal core (9) and the guide slope (11) at the root end of the overhanging rod (12). By pushing it into the insertion hole (13), an overhanging force is given to the trapezoidal core (9).
The fan-shaped core (8) is provided with the expanding / contracting diameter core (6) to which the overhanging force is given to the outside through the (9). Particularly in the present invention, the expansion / contraction diameter core (6) is mounted on the inner die (2) of the socket for forming the rubber ring mounting groove (45) of the socket (44) of the pipe joint. Sliding plates (14, 15, 16) are connected to (12), the expansion / contraction diameter guide (7) of the expansion / contraction diameter core (6), and the socket inner mold (2). Moving plate (14,15,1
The extension rod (12) is inserted into and withdrawn from the expansion / contraction diameter core (6) via 6), and the expansion / contraction diameter guide (7) slides in the core expansion and core expansion directions, The inner mold (2) of the receiving part is pulled out from the receiving part (44) which is inserted and molded in the mold (1), and the sliding plate (14) of the expansion / contraction diameter guide (7) is attached to the protruding rod ( 12)
The sliding plate (16) of (1) is slid by being pulled and pushed by the sliding plate (16) of the projecting rod (12) by contacting the sliding plate (16) with a predetermined play, The sliding plate (15) is also the sliding plate (16) of the projecting rod (12).
It is desirable to adopt a configuration that slides by being pushed or pulled by.

[0006]

[Operation] By sliding the expansion / contraction diameter guide (7) in the forward and reverse directions with respect to the fan core (8) and the trapezoid core (9), the fan core (8) and the trapezoid core (9) ) And expand or reduce the diameter. During the expanded state, that is, during molding, the fan-shaped core (8) and the trapezoidal core (9) form a circumference corresponding to the inner circumference of the rubber ring mounting groove (45). At this time, if the projecting rod (12) is pushed into the insertion hole (13) formed between the trapezoid core (9) and the guide slope (11) of the expansion / contraction diameter guide (7), the trapezoid core Child (9)
Is given an overhanging force to the outside, and the fan-shaped core (8) is also given an overhanging force to the outside through the trapezoidal core (9). Therefore, the T-shape of the fan-shaped core (8) is Rattling between the fitting portion (8A) and the guide dovetail groove (10) of the expansion / contraction diameter guide (7) is eliminated, and is formed by the fan-shaped core (8) and the trapezoidal core (9). There are almost no irregularities on the circumference.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described with reference to one embodiment shown in FIGS. 1 to 11, in which an injection molding die (1) is an inner die (2) for a receiving portion, a remaining inner die (3), and An outer mold (4) is provided, and an expansion / contraction diameter core (6) for forming a rubber ring mounting groove is mounted in the internal space (5) of the receiving part inner mold (2).

As shown in FIGS. 3 and 4, the expansion / contraction diameter core (6) comprises an expansion / contraction diameter guide (7), a fan core (8) and a trapezoid core (9). (7) has a taper shape in which the diameter decreases from the root end to the tip, and guide dovetail grooves (10) and guide slopes (11) are alternately formed on the peripheral surface, and as shown in FIG. The inclination of the guide slope (11) is set to be steeper than the inclination of the guide dovetail groove (10),
A T-shaped fitting portion (8A) formed at the root end of the fan-shaped core (8) is slidably fitted in the guide dovetail groove (10), and is fitted in the guide slope (11). The root edge of the trapezoidal core (9) slidably contacts. In this state, both sides of the trapezoidal core (9) are fan-shaped cores.
Both sides of (8) are pressed down from the outside to prevent them from popping out. An insertion hole (13) for inserting the overhanging rod (12) is formed between the trapezoidal core (9) and the guide slope (11) at the root end of the expansion / contraction diameter guide (7). There is. A taper portion (12A) is formed at the tip of the projecting rod (12).

The inner mold (2) of the receiving part has a tapered connecting part (17)
Connected to the sliding plate (14) via the expansion / contraction diameter core (6)
The expansion / contraction diameter guide (7) of the slide plate is connected via the connecting rod (18).
(15) and the overhanging rod (12) is connected from the sliding plate (16).

The sliding plates (14, 15, 16) are slidably installed on a base (19) and guided by the sliding frames (20, 20) on the left and right. The sliding plate (16) of the overhanging rod (12) has a bracket (2) as shown in FIGS.
The connecting plate (22) is connected via 1), and the connecting plate (22)
A cross beam (23) is attached to the end of the cross beam (23), and piston rods (25, 2) of the hydraulic cylinders (24, 24) are attached to both ends of the cross beam (23).
5) is connected.

As shown in FIGS. 5 and 6, the expansion / contraction diameter core
A connecting plate (26) is connected to the sliding plate (15) of (6), and a pair of left and right pins (27, 27) are provided upright at the tip of the connecting plate (26). The pins (27, 27) are slidably fitted in the elongated holes (28, 28) provided at the bottom of the sliding plate (16) of the overhanging rod (12).

As shown in FIG. 2 and FIG.
The sliding plate (14) of (2) communicates with the leading sliding plate (30) via a pair of left and right connecting plates (29, 29) and a connecting pipe (29A). ) Is another sliding plate
Like (14,15,16), it is slidably installed on the base (19) guided by sliding frames (20,20).

The sliding plate (15) of the expansion / contraction core (6) and the sliding plate (16) of the overhanging rod (12) are connected to the pins (27, 27),
Lock holes (3) of the connecting plate (26) that connect via the long holes (28, 28).
1) The electromagnetic cylinder (33) mounted in the base (19)
5 (see FIGS. 5 and 6), and the sliding plate (14) of the inner mold (2) of the receiving part and the leading sliding plate (30) are engaged with each other. The lock hole (34) of the connecting plates (29, 29) to be connected is adapted to engage the pin (35) of the electromagnetic cylinder (36) mounted in the base (19) (Fig. 2). ,
(See FIG. 6).

Further, as shown in FIGS. 5 and 6, an electromagnetic cylinder (39) in which a pin (38) engages with a lock hole (37) of a sliding plate (16) is inserted in the connecting plate (26). As shown in FIGS. 6 and 9, each connecting plate (29, 29) has a sliding plate (15).
The electromagnetic cylinder (4
2) is interpolated.

In the above structure, the overhanging rod (1
2) is the guide slope of the trapezoidal core (9) and the expansion / contraction diameter guide (7)
(11) is pushed into the insertion hole (13) formed between the trapezoidal core (9) and the trapezoidal core (9) to the fan-shaped core (8). Is given, the circumference formed by the fan-shaped core (8) and the trapezoidal core (9), that is, the molding (4
Almost no unevenness is present in the inner peripheral molding portion of the rubber ring mounting groove (45) of the receiving portion (44) of 3), and the rubber wheel mounting groove (45) having a smooth inner periphery is molded.

After molding, the hydraulic cylinder (24) is operated from the state shown in FIGS. 1, 2 and 5 to move the cross beam (23) and the connecting plate (2).
The sliding plate (16) is slid in the direction of arrow (i.e., forward direction) in FIG. 5 via 2) to bring it to the state shown in FIG. 8, and the extension rod (12) is pulled out from the expansion / contraction diameter core (6). At this time, the connecting plate (26) of the sliding plate (15) of the expanding / contracting diameter core (6), the sliding plate (14) of the receiving part inner mold (2) and the leading sliding plate (30) are connected. The pair of left and right connecting plates (29, 29) is locked so that the pins (32, 35) of the electromagnetic cylinders (33, 36) engage with the respective lock holes (31, 34) to prevent sliding. ing.

The sliding plate (16) comes to the position shown in FIG.
When the projecting rod (12) is completely withdrawn from the expansion / contraction diameter core (6), the pin of the connecting plate (26) is attached to the rear end of the elongated hole (28, 28) of the sliding plate (16). (27) is located and at the same time the sliding plate (1
The position of (6) is detected by a photoelectric sensor etc. and the electromagnetic cylinder (3
3) is operated to disengage the pin (32) of the electromagnetic cylinder (33) from the lock hole (31) of the connecting plate (26) and unlock the connecting plate (26) as shown in FIG. To do.

Thus, the connecting plate (26) of the sliding plate (15) becomes slidable and is pulled by the sliding plate (16) through the pins (27, 27) and the elongated holes (28, 28). 8 Sliding in the direction of arrow a, the expansion / contraction diameter guide (7) of the expansion / contraction diameter core (6) is the sliding plate.
(15) slides in the same direction through the connecting rod (18), and the T-shaped fitting portion (8A) of the fan-shaped core (8) is relatively expanded and contracted by the guide.
Slide the guide dovetail groove (10) of (7) toward the tip,
(9) is pushed by the fan-shaped core (8) and slides on the guide slope (11) of the expansion / contraction diameter guide (7).
(6) shifts from the expanded state shown by the dotted line to the reduced state shown by the solid line as shown in FIG. 10, and the sliding plate (16) shown in FIG.
Comes into contact with the leading sliding plate (30), and when the expansion / contraction diameter core (6) is in a completely reduced diameter state, it is completely separated from the rubber ring mounting groove (45) of the molded receiving portion (44). . In this state, the position of the sliding plate (16) is detected by a photoelectric sensor or the like to operate the electromagnetic cylinder (36), and the pin (35) of the electromagnetic cylinder (36)
9 from the lock hole (34) of the connecting plate (29, 29).
The lock of the connecting plates (29, 29) is released as shown in FIG.

The sliding plate (16) is made by pulling the sliding plate (15) as described above, and further the leading sliding plate (30).
Push and slide. Then the leading sliding plate (30)
Pulls the sliding plate (14) through the connecting plate (29, 29) unlocked as described above, and as shown in FIG. 11, the receiving part (44) formed with the receiving part inner die (2) is formed. ).

When the die (2) in the receiving part is set in the die, the electromagnetic cylinder (39) of the connecting plate (26) is operated in the state shown in FIG. 11 to move the pin (38) to the sliding plate ( 16) Engage with the lock hole (37) of the sliding plate (15) and engage the electromagnetic cylinder (42) of each connecting plate (29, 29) with the pin (41) into the lock hole (40) of the sliding plate (15). Engage. In this way, connecting plate (26) and sliding plate (16) and connecting plate (29, 29) and sliding plate
The hydraulic cylinder (24) is operated in a state where (15) and are locked, and the connecting plate (26) and the sliding plate (16) are connected via the connecting plate (22).
Also, slide the sliding plate (14) through the connecting plates (29, 29), the sliding plate (15), and the leading sliding plate (30) in the arrow B direction (rearward direction) to expand / contract the diameter. The inner mold (2) in the receiving part is set in the mold while the diameter of the child (6) is reduced.

Next, the electromagnetic cylinder (4
2) actuate so that the pin (41) locks the sliding plate (15)
Pull out from (40) to connect plate (29, 29) and sliding plate (15)
And the sliding plate (16) and sliding plate (15) together in the direction of arrow B
(6) is expanded.

Finally, the electromagnetic cylinder (39) of the connecting plate (26) is operated to move the pin (38) into the lock hole (37) of the sliding plate (16).
The connecting plate (26) and the sliding plate (16) to be unlocked, and only the sliding plate (16) is slid to extend the expansion rod (12) into the expansion / contraction core (6). Push it into the insertion hole (13) between the guide slope (11) of the expansion / contraction diameter guide (7) and the trapezoidal core (9), and insert it outside the trapezoidal core (9) and the fan-shaped core (8). Providing a bulging force toward the direction, at this time, the electromagnetic cylinder (36) is operated to cause the pin (35) to project upward, and the pin (35) is engaged with the lock hole (31) of the connecting plate (26). Lock the sliding plate (15). In this way, the injection molding die (1) returns to the standby state shown in FIGS. 1, 2 and 5.

[0023]

According to the present invention, in the expansion / contraction diameter core for forming the rubber ring mounting groove of the pipe joint or the pipe receiving portion of the drainage basin,
By pushing an overhanging rod into the insertion hole between the guide slope of the expansion / contraction diameter guide and the trapezoidal core, a trapezoidal core is provided, and the fanouter core is given an outwardly overhanging force through the trapezoidal core. Almost no irregularities are formed on the circumference formed by the core and the trapezoidal core, so that the rubber ring mounting groove having a smooth circumference can be formed.

[Brief description of drawings]

1 to 11 show a specific example of the present invention.

[FIG. 1] Plan cross-sectional explanatory view

FIG. 2 is a side cross sectional explanatory view (central cross section).

[Fig. 3] Exploded perspective view of the expandable core

[Fig. 4] Explanatory view of expanded state

FIG. 5 is a side cross sectional explanatory view (end cross section).

FIG. 6 is an explanatory view of the arrangement of connecting plates.

[Fig. 7] Angle explanatory view of guide groove and guide slope

FIG. 8 is an explanatory side cross-sectional view of a protruding rod in a pulled-out state.

FIG. 9 is an explanatory view of a side cross-sectional explanatory view in a reduced diameter state.

FIG. 10 is an explanatory diagram of a reduced diameter state.

FIG. 11 is a sectional side view of the die in the receiving part with the die pulled out.
4 shows a conventional example.

FIG. 12 is an exploded perspective view of the expansion / contraction diameter core.

FIG. 13 is an explanatory diagram of a diameter expansion state.

FIG. 14 is an explanatory diagram of a reduced diameter state.

[Explanation of symbols]

1 injection mold 2 Mouth type 6 Expansion / contraction core 7 Expansion / contraction diameter guide 8 fan-shaped core 8A T-shaped fitting 9 trapezoidal core 10 guide dovetail 11 Guide slope 12 Overhanging rod 13 insertion hole 14,15,16 Sliding plate 43 Molded product 44 Receptacle 45 Rubber ring mounting groove

Continuation of the front page (56) Reference JP-A-56-118833 (JP, A) JP-A-5-147082 (JP, A) JP-A-6-154944 (JP, A) JP-A-6-213087 (JP , A) Actual development Sho 50-148355 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B29C 33/44-33/54 B29C 45/40-45/44

Claims (3)

(57) [Claims] 1. An expansion / contraction diameter guide having a taper shape whose diameter is reduced from the root end to the tip, and a guide dovetail groove and a guide slope are alternately provided on the peripheral surface, and a T-shaped fitting portion. It is composed of a fan-shaped core formed at the root end and a trapezoidal core, the inclination of the guide slope is set to a steeper angle than the inclination of the guide dovetail groove, and the T-shaped fitting portion of the fan-shaped core is It is slidably fitted in the guide dovetail groove of the expansion / contraction diameter guide, the trapezoidal core is slidably arranged on the guide slope, and both sides of the trapezoidal core are held by both sides of the fan-shaped core. Further, at the root end of the expansion / contraction diameter guide, an insertion hole for inserting an extension rod is formed between the trapezoidal core and the guide slope, and by pushing the extension rod into the insertion hole, the trapezoid External force is applied to the child, and the fan-shaped core is also exposed to the outside through the trapezoidal core. Scaling wherein the overhang force is applied to 径中Ko 2. The expanding / contracting diameter core is mounted on an inner mold of a receiving part for forming a rubber ring mounting groove in the receiving part of a pipe joint, the expansion rod, the expanding / contracting diameter guide of the expanding / contracting core, and Sliding plates are respectively connected to the inner molds of the receiving portions, the projecting rods are inserted into and pulled out from the expansion / contraction diameter cores via the sliding plates, and the expansion / contraction diameter guides are used to expand the cores. The expansion / contraction diameter core according to claim 1, wherein the inner die of the receiving portion slides in the diameter reducing direction, and the inner die of the receiving portion is pulled out from the receiving portion that is inserted and molded in the mold. 3. The sliding plate of the expansion / contraction diameter guide slides by being pulled and pushed by the sliding plate of the extension rod by contacting the sliding plate of the extension rod with predetermined play, The expansion / contraction diameter core according to claim 2, wherein the sliding plate inside the receiving portion also slides by being pushed or pulled by the sliding plate of the projecting rod.