JPS6334899Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an injection mold having a mold structure for automatic runner removal.

Conventionally, when a sprue, runner, and gate were installed on the slide core, when the slide core moved, the sprue, runner, and gate also moved, so springs were used to push each part of the sprue, runner, and gate out of the slide core. However, the extrusion operation was uncertain and it was difficult to automatically take out the runner part, etc., making it difficult to fully automatic molding.

This idea was made in view of the above points, and by using the extrusion force of the molding machine while using a slide core, each part of the sprue, runner, and gate can be reliably extruded, and the runner part etc. The purpose is to enable automatic take-out molding and fully automatic injection molding.

Hereinafter, one embodiment of the injection molding mold according to this invention will be described in detail based on the drawings.

Figure 1 is a sectional view of the mold during clamping molding, Figure 2 is a sectional view taken along the line - - in Figure 1, and Figure 3 shows the slide core retracting with a solid line, and the time of completion of extrusion with a chain double-dashed line. FIG.

The illustrated molding die has a core 19 and an upper mold 1.
8 is arranged to move up and down, and a slide core 1 that forms a cavity in cooperation with the upper mold 18 is slidably arranged on the core 19.
A block 2 is arranged on the slide core 1, which remains in place relative to the slide core 9.

The slide core 1 described above has a diagonal pin 2 fixed to the upper die 18 at an angle θ in the diagonal hole 27.
2 is slidably inserted, and when the upper mold 18 vertically rises, the slide core 1 is configured to be able to retreat in the direction of the arrow in FIG. The pin 9 is inserted into the vertical hole of the block 2, and the upper mold 18 is raised and the slide core 1
The structure is such that the block 2 can maintain its fixed position when the block 2 is retracted.

Further, the block 2 is provided with a sprue 3, a runner 4, and a gate 5.

An ejector pin 6 is positioned coaxially with the sprue 3, and the pin 6 is held between an upper ejector plate 7 and a lower ejector plate 8. Further, a hole 1' is provided in the slide core 1 so that the slide core 1 does not interfere with the ejector pin 6 even if the slide core 1 moves backward.

A pin 10, a spring 11, and a set screw 12 are built into the slide core 1. Further, on the sliding surface side of the block 2 with the slide core 1, a counterbore 13 1 is provided so that the tip of the pin 10 is placed in a position opposite to the original position of the slide core 1 and the retracted position of the slide core ₁ . 13 ₂ are provided.

Next, the operation of the injection mold constructed as above will be explained.

The slide core 1 is moved backward simultaneously with the opening of the mold by means of an inclined pin 22 connected to the upper mold 18. However, the retracted position is restricted by the bolt 17. At this time, the block 2 maintains its original position by fitting the pin 9 connected to the upper die 18. The stroke of slide core 1 is S, and the angle of the inclined pin is θ.
Then, the relationship between the length l of the fitting part of pin 9 is l=
It becomes S/tanθ.

Also, the original position of the block 2 is determined by the pin 10 and the counterbore 13 when the slide core 1 is retracted.
₂ ensures that this is maintained. When the slide core 1 retreats, the pin 10 is held down by the sliding surface of the block 2,
When it is aligned with the counterbore position 13 ₂ , it is pushed up by the spring 11, showing the effect of positioning.

As explained above, since the block 2 maintains its original position even if the slide core 1 retreats, the sprue 3, runner 4, and gate 5 can maintain their original positions.

Next, when an extrusion force F is applied to the extrusion rod 23 of the molding machine, the lower ejector plate 8,
The upper ejector plate 7 and the ejector pin 6 move forward. Therefore, the sprue portion 3, runner portion 4, and gate portion 5 are reliably pushed out.
The runner can be checked reliably and fully automatic molding is possible.

As a means for retaining the original position of block 2, pin 1 is used instead of pin 9 as shown by the chain line in FIGS. 1 and 2.
4 can be used. The pin 14 is housed in a plate 16 that is connected to the core 19 with bolts 20 and is held with a set screw 15. As is clear from the drawings, with this means, the position of the tip of the pin 14 remains unchanged, and the block 2 is maintained at its original position even when the slide core 1 is retracted.

Note that when performing two-stage extrusion, a two-stage push pin 24 as shown in FIG.
l' is provided on the plate 25. Further, the product section is provided with a product push-out pin 26 for pushing out the product. When an extrusion force F is applied to the extrusion rod 23 during molding, the upper ejector plate 7,
The lower ejector plate 8 and the product push pin 26 move forward at the same time, but the two-stage push pin 24
moves forward with a delay of the time of the gap l′. Due to this time delay, the product 21 and the gate 5 are disconnected.

As explained above, the injection mold according to the invention includes a slide core 1 provided to slide back and forth on the block 2, a sprue 3, a runner 4, and a gate 5 provided on the upper surface of the block 2. The sprue 3 Since the runner 4 and gate 5 are reliably extruded from the block 2, the runner can be taken out of the mold by an existing method without any inconvenience, and can be reliably and automatically carried out by using the extrusion force of the molding machine. It has the effect of

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of the mold during clamping molding, Figure 2 is a cross-sectional view taken along the line - in Figure 1, and Figure 3 shows the slide core retracting with a solid line, and the time of completion of extrusion with a chain double-dashed line. FIG. 2 is a sectional view similar to FIG. 1; 1: Slide core, 2: Block, 3: Sprue, 4: Runner, 5: Gate, 6: Ejector pin, 7: Upper ejector plate, 8: Lower ejector plate.

Claims (1)

[Scope of utility model registration request] A slide core is provided to slide back and forth on a fixed block 2, a sprue 3, a runner 4, and a gate 5 are provided on the top surface of the block 2, and an ejector pin 6 is provided below the sprue 3. 6 is configured to apply the extrusion force of the extrusion rod 23 of the molding machine via the upper ejector plate 7 and the lower ejector plate 8, thereby ensuring that the sprue section, runner section, and gate section are extruded from the block 2. Characteristic injection mold.