JPH0439406B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multi-cavity mold, and more particularly to a multi-cavity mold in which a plurality of inserts are interchangeably positioned and fixed to a mold body. Regarding types.

In recent years, with the diversification of molded product descriptions and the reduction in molded product inventory, there has been a need for high-variety, low-volume production. The aim is to shorten replacement time, reduce mold costs, and make more efficient use of mold stock space by downsizing the mold.

In conventional molding molds in which only the insert is replaced, as shown in JP-A-54-137433, the insert and the insert insertion recess of the mold body are square-shaped, and the mold body is There is a bolt that is inserted into the insert and screwed into the insert, and then pulled and fixed to a predetermined corner of the insert insertion recess.

In such a mold, the insert is fixed with its two surfaces in contact with the mold body, so the positioning accuracy is improved, and the cavities, runners, etc. formed in the insert are fixed with the two surfaces as the reference plane. It has the advantage of being easy to process.

However, in this mold, the insert is positioned and fixed with a bottle, and when replacing the insert, it must be removed by turning the bolt each time, making it difficult to mold multiple pieces using multiple inserts. When doing this, there was a problem in that it required a considerable amount of time to replace the inserts.

The present invention has been made in view of the above circumstances, and its purpose is to shorten the time for replacing inserts and to fix the positioning of the inserts in multi-cavity molding using a plurality of inserts. It is an object of the present invention to provide a multi-cavity molding die that allows easy insertion and fixation of each insert into a desired insert insertion recess of a mold body with compatibility.

The feature is that a plurality of nest insertion recesses are opened in the parting surface of the mold body, and are composed of wall surfaces at least two of which intersect with each other to form a corner, and the intersecting angles of the wall surfaces are the same. A mutually compatible insert having a polygonal cross-sectional shape whose position is regulated by the wall surface of the insert insertion recess and is installed in each of the insert insertion recesses; a pressing slope formed at a corner located at a position opposite to the corner of the insert that contacts the corner of the child insertion recess; and a pressing slope provided on the mold body to press the pressing slope. and a pressing means for positioning and fixing the insert in the insert inserting recess.

Hereinafter, preferred embodiments of the present invention will be described in detail based on the accompanying drawings.

In Fig. 1 showing the parting surface of one mold which is a split mold (the other mold is constructed in the same way), 1 is a mold body, and this mold body 1 includes Four insert insertion recesses 2 are formed leaving a cross-shaped partition wall 1a at the center of the parting surface. The two perpendicular surfaces of the partition wall 1a serve as regulating surfaces 2a of each nest insertion recess 2.

Reference numeral 3 designates four nests inserted into each of the nest insertion recesses 2, and the outer shapes of the nests are the same. That is, the shape of the parting surface of the insert 3 is approximately square, and the corner opposite to the corner 3b formed by the contact surface 3a that contacts the regulation surface 2a is cut off to form a pressing slope 3c ( below,
A pressing surface 3c (sometimes referred to as a pressing surface 3c) is formed. Note that this pressing surface 3c is a slightly inclined surface toward the bottom surface of the insert inserting recess 2 in order to prevent the insert 3 from floating up.

Reference numeral 4 denotes a fixture for positioning and fixing each insert 3 in the insert inserting recess 2 by having its tip surface abut against the pressing surface 3c, and is guided inside the mold body 1 and is movable in the left and right directions in FIG. It is becoming.

Reference numeral 5 denotes a cylinder for simultaneously advancing and retracting two fixtures 4 located in the vertical direction in FIG. be done. Then, the cylinder rod 5a of the cylinder 5 and the cylinder case 5
A rotatable arm 7 and an arm 8 extending in the opposite direction of the arm 7 are attached to shafts 6 respectively attached to b, and the arm 7 and the fixture 4 are connected via a shaft 9. A shaft 10 provided at the tip of the arm 8 is guided by a groove provided in the mold body 1 and moves in the same direction as the moving direction of the fixture 4.

Reference numeral 11 denotes a stop pin that restricts the forward movement of the arm 8, the tip of which is connected to the shaft 10 at the advanced position of the arm 8.
The proximal end is pressed by a disc spring 11a.

The cylinder 5 on the right side in FIG.
After that, insert the cylinder 5 on the left side in Figure 1.
When driven to the extension side as shown, the fixture 4 presses the pressing surface 3c of the insert 3, the contact surface 3a of the insert 3 is pressed against the regulating surface 2a, and each insert 3 is positioned and fixed. .

In addition, since each insert 3 has the same shape, it can be placed in any insert insertion recess 2 with compatibility, and when the cylinder 5 is driven to the extension side, the shaft 6 Since the axes of 9 and 10 coincide on the same line, the reaction force from the insert 3 is applied to the cylinder 5.
Since it does not act directly on the plate spring 11a, but only acts on the disc spring 11a, the fixation of the insert 3 is stable.

Next, a runner structure suitable for use in a molding die in which the compatible insert 3 is positioned by the cross-shaped partition wall 1a as described above will be explained.As shown in FIG. A sprue 12 is formed at the center of the partition wall 1a of the nozzle side mold body 1 of the mold which is divided into two parts, and the partition wall 1a of the other mold body 1 has a sprue 12 on its parting surface. Runners 13 are carved that extend from the center in the left-right direction in FIG. 1, have respective tips branching in two directions, and reach each insert 3 at positions equidistant from each corner formed by the reference surface 2a.

The runner 1 is placed on the parting surface of each nest 3.
A cavity (not shown) is located corresponding to the tip of 3.
A runner 14 that extends from the top to one contact surface 3a, and a runner 15 that opens to the other contact surface 3a and is located at the same distance from the corner 3b formed by the two contact surfaces 3a.
is carved, and the runners 14 and 15 are in communication.

Therefore, each insert 3 is inserted into any insert insertion recess 2.
Even if it is inserted into the runner 14 or 15 of nest 3,
Either one of them will necessarily communicate with the runner 13 of the mold body 1, making it easy to replace the insert 3.

Next, we will explain a runner exchange device that uses a plurality of inserts 3 and is suitable for use in the aforementioned high-mix, low-volume production by exchanging them.The gate position differs depending on the molded product. In addition to those in which runners are provided on the parting surface as shown in FIG. 1, there are also those in which a gate is formed on the bottom surface of the cavity of the insert.

Therefore, if the mold body is replaced every time inserts with different gate positions are replaced, the purpose of adapting to high-volume, low-volume production by replacing only the inserts cannot be achieved.

Therefore, the runner plate 16 is connected to the nozzle bush 17 and the insert 3 as shown in FIGS. 2 and 3.
The mold body 1 is positioned between the mold body 1 and the nozzle side surface of the mold body 1, and is slidably arranged in a direction parallel to the parting surface.

Then, on the nozzle side of the runner plate 16,
Various flow paths for molten resin are formed at predetermined intervals in the sliding direction of the runner plate 16.

That is, in FIG. 3, 18 is a runner formed in an X-shape, into the center of which molten resin is supplied from a nozzle, and from a through hole 18a bored at each tip to the bottom surface of each insert 3. leak.

Reference numeral 19 denotes a through hole bored at a predetermined interval from the center of the runner 18 in the sliding direction of the runner plate 16, and when the runner plate 16 slides and the through hole 19 is in a position facing the nozzle, It communicates with the sprue 12 formed in the partition wall 1a of the mold body 1 shown in FIG.

Reference numeral 20 denotes a runner formed in an H shape, the center of which is formed in the sliding direction of the runner plate 16 from the through hole 19 with the same distance as the center of the runner 18 and the center of the through hole 19. There is. The molten resin supplied from the nozzle to the center of the runner 20 flows out to the bottom surface of each insert 3 from through holes 20a formed at each tip of the runner 20.

21 is a through hole for fixing the runner plate 16 at a position where the centers of the runner 18, the through hole 19, and the runner 20 coincide with the nozzle center, and the runner 18,
The through holes 19 and the runners 20 are formed at the same distance from each other, and the positioning pins 22 are inserted therein.

A cylinder 23 slides and drives the runner plate 16, and the stroke of the cylinder 23 is approximately the same as the distance between the center of the runner 18 and the center of the through hole 19. Therefore, in one reciprocating movement of the cylinder 23, the runner plate 16 can only be slid by one pitch.
A progressive mechanism is provided that sequentially slides the runner plate 16 by reciprocating the runner plate.

This sequential feeding mechanism is carried out by the rod 23 of the cylinder 23.
It is rotatably attached to the tip of the rod 23a and biased toward the side of the rod 23a, and the tip shape is
A locking pawl 24 formed in a 90 degree wedge shape,
A groove 25 is formed in the runner plate 16 at a position corresponding to the rod 23a and guides the rod 23a, and a center pitch between the runner 18 and the through hole 19 is formed on the opposite surface of the groove 25 to the locking pawl 24. A plurality of engaging protrusions 26 protrude at the same pitch and with which the tips of the locking pawls 24 engage when the rod 23a moves forward or backward; located in the groove 25
It is formed of two wide parts 25a and 25b for switching the direction of the locking pawl 24.

Therefore, the runner 18 is used for the runner plate 16 in the position shown in FIG.
When using the runner 20 by replacing the cylinder 23, the cylinder 23 may be driven back and forth twice. and through hole 1
9, it is sufficient to reciprocate the cylinder 23 once to move the locking pawl 24 to the widened part 25a, change the direction of the locking pawl 24, and then reciprocate the cylinder 23 once. The molten resin flow path can be selected according to the insert 3 to be used.

In the above-mentioned embodiment, the respective inserts 3 are arranged so that their pressing surfaces 3c form a V-shape, but the invention is not limited to this. For example, the pressing surfaces 3c of adjacent inserts 3 may be arranged in a V-shape. The insert 3 may be fixed with a fixture having a V-shaped tip.

In this way, according to the present invention, the insert is made compatible so that it can be inserted into any insert inserting recess, so the insert can be inserted into any insert inserting recess.

Furthermore, by forming a pressing slope on the side wall surface of the insert at a corner opposite to the corner of the insert that contacts the corner of the insert insertion recess, the pressing means can be The insert can be replaced by releasing the pressure on the pressing slope, and the insert can be easily positioned and fixed in the insert insertion recess simply by pressing the pressing slope of the replaced insert with the pressing means. .

As described above, according to the mold of the present invention, it is possible to easily replace the insert, so that it can be suitably used for high-mix, low-volume production.

Although the present invention has been variously explained above with reference to preferred embodiments, the present invention is not limited to these embodiments, and it goes without saying that many modifications can be made without departing from the spirit of the invention. It is.

[Brief explanation of drawings]

The drawings show a preferred embodiment of the present invention, in which Fig. 1 is a plan view showing one parting surface of a split mold, and Fig. 2 is a cross-sectional view taken along line A-A in Fig. 1. , FIG. 3 is a sectional view taken along line BB in FIG. 2. DESCRIPTION OF SYMBOLS 1... Mold body, 1a... Partition wall, 2... Insert insertion recess, 2a... Regulation surface, 3... Insert, 3a...
...Abutting surface, 3b... Corner, 3c... Pressing surface, 4...
...Fixing tool, 5...Cylinder, 5a...Cylinder rod, 5b...Cylinder case, 6...Shaft, 7,
8... Arm, 9, 10... Axis, 11... Stop pin, 11a... Belleville spring, 12... Sprue, 1
3, 14, 15...Runner, 16...Runner plate, 17...Nozzle bush, 18...Runner, 18a...Through hole, 19...Through hole, 20...Runner, 20a...Through hole, 21... ...Through hole, 22...
Positioning pin, 23... cylinder, 23a... rod, 24... locking claw, 25... groove, 25a, 2
5b... Widened portion, 26... Engaging protrusion.

Claims (1)

[Scope of Claims] 1. A plurality of nested inserts that are opened in the parting surface of the mold body and that are composed of wall surfaces at least two of which intersect with each other to form a corner, and the intersecting angles of the wall surfaces are the same. a recess, a mutually compatible insert having a polygonal cross-sectional shape, which is mounted in each of the insert insertion recesses with its position regulated by the wall surface of the insert insertion recess; and a side wall surface of the insert. a pressing slope formed at a corner opposite to the corner of the insert that contacts the corner of the insert insertion recess; and a pressing slope provided on the mold body, the pressing slope being 1. A multi-cavity molding die, comprising a pressing means for positioning and fixing the insert in the insert insertion recess by pressing.