JPH0523295Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a quick return device for a mold ejector plate in a vertical or horizontal molding machine.

[Conventional technology]

A lower mold 3 and its pedestal 4 are fixed on columns 2 and 2 fixed on both sides of the base 1, and an upper mold 5 and a support 6 are fitted above the lower mold 3 so as to move up and down. do.

Below the pedestal 4 is an ejector plate 7.
The ejector plate 7 is fitted with ejector pins 9, 9 for ejecting the product 10. The mold 3 is plunged into the through hole 11 of the mold 3. Note that 12 is a compression spring inserted between the ejector plates 7 of the lower mold 3.

FIG. 1 shows the mold clamping resin injection state, in which the upper mold 5 has descended and is in contact with the lower mold 3.

FIG. 2 shows the state in which the mold opening and protrusion have been completed. The upper mold 5 and its support base 6 have risen and are separated from the lower mold 3, and the lifting stage 7 has also risen and is lowered by its ejector pins 9. The product 10 in the mold 3 is pushed up and discharged.

FIG. 3 shows a state in which the ejector return is completed, and the ejector plate 7 is lowered by the action of the push-up rod 8 and the compression spring 12, and the ejector pin 9,
The upper end of the mold 9 returns to a position where it is lined up with the upper surface of the lower mold 3, and from this state the next mold clamping is started.

[Problem that the invention attempts to solve]

However, if the above-mentioned molding operation is repeated many times, the force of the compression spring 12 weakens, the lowering speed of the ejector plate 7 and the ejector pins 9 becomes slow, and the return operation becomes incomplete.

For this reason, it has been proposed to connect a toggle lock mechanism to the ejector plate 7 and operate it in conjunction with the movement of the upper die, but this has a complicated structure and is expensive.

[Means for solving problems]

The present invention consists of a lower mold 3, an upper mold 5 provided to open and close the lower mold 3, and an ejector plate 7 to which ejector pins 9, 9 for ejecting the product 10 from the lower mold 3 are pivotally connected. A rod cam 20 is fixed to one of the upper mold 5 and the ejector plate 7, and a pincer 2 facing the rod cam 20 is fixed to the other.
2, 22 are pivotally mounted, and the pincers 22, 2 are mounted on the pedestal 4.
This is a quick return device for an ejector plate of a mold in a molding machine, characterized in that a cam guide 25 having cam surfaces b, b for holding the tip of the mold is fixedly provided.

In addition, in the case of a horizontal molding machine, the above-mentioned lower mold 3 and upper mold 5
shall mean a pair of left and right types.

[Effect]

When the lower mold 3 and upper mold 5 close, the rod cam 20 first
The ejector plate 7 is lowered because the ends of the pins 22, 22 are closed, and the ejector pin 9 is reliably retracted into the lower mold 3, and then the lower mold 3 and the upper mold 5 are closed.

〔Example〕

An embodiment of the present invention will be described in detail below.

As shown in the fourth figure, the upper end of a rod cam 20 extending downward is fixed to the side surface of a support base 6 that supports the upper mold 5. The lower end of this rod cam 20 is formed into an arc shape.

A seat plate 21 as shown in FIG. The rod cam 2 is pivotally connected by 23, 23, and the rod cam 2 is mounted between the clips 22, 22.
A compression spring 24 is inserted between the recesses 26, 26 provided between the lower portions of the notches a, a into which 0 is inserted.

A cam guide 25 as shown in FIG. Insert the tip so that it slides. The cam surfaces b and b open downward,
On the other hand, the outer surfaces of the upper ends of the pincers 22, 22 are formed into slopes c, c that face them, and the inner surfaces of their upper ends are formed into slopes d, d into which the lower ends of the rod cams 20 are inserted.

Next, the operation of this device will be explained.

As shown in the second figure, when the mold opening projecting is completed, the upper portions of the clips 22, 22 are inserted into the cam guide 25, and are closed by being pushed inward by the cam surfaces b, b.

Thus, when the upper die 5 descends, the lower end of the bar cam 20 is first inserted between the slopes d and d of the upper ends of the clips 22, 22, but the clips 22, 22 are inserted into the cam guide 25.
Since it is held between the cam surfaces b and b of the ejector plate 7, it does not open and is pushed downward.
Then, the ejector pins 9, 9 are surely lowered.

In this way, when the ejector pins 9, 9 are completely lowered, the pins 22, 22 escape from the inside of the cam guide 25 downward, and the pins 22, 22 are opened by the spring 24 and elasticity, and the rod cam 20 is opened as shown in the first figure.
is inserted into the notch a between the clips 22, 22.

Although the above embodiment shows the case where the present invention is applied to a vertical molding machine consisting of a lower mold 3 and an upper mold 5, the present invention can be applied not only to a vertical molding machine but also to a horizontal molding machine. In this case, the lower mold 3 and the upper mold 5 form a pair of horizontal molds.

[Effect of idea]

As described above, according to the present invention, the lower mold 3 and the upper mold 5 are closed with the ejector pin reliably retracted from the lower mold 3, so the operation is reliable, but the cam guide 25 is 4, there is no possibility of malfunction, and since the present invention has a simple structure, it is easy to install and can be provided at low cost.

[Brief explanation of the drawing]

Fig. 1 is a front view of an embodiment of the present invention in a mold clamping resin injected state, Fig. 2 is a front view of the same mold in a state in which ejection is completed when the mold is opened, Fig. 3 is a front view of the same in a state in which ejection and return are completed, and Fig. 4 is a front view. 5 is a front view of the seat plate, FIG. 6 is a front view of the clip, and FIG. 7 is a front view and a plan view of the cam guide. 3...Lower die, 5...Upper die, 7...Ejector plate, 9,9...Ejector pin, 10...
...Product, 20... Rod cam, 22, 22... Pincer,
b, b...Cam surface, 25...Cam guide.

Claims (1)

[Scope of utility model registration request] A lower mold, an upper mold provided to open and close it,
It consists of an ejector plate to which an ejector pin is pivotally attached for ejecting the product in the lower mold, and a rod cam is fixed to one of the upper mold and the ejector plate, and the other is a pincer opposite to the rod cam. A device for quickly returning an ejector plate of a mold in a molding machine, characterized in that a cam guide having a cam surface for holding the tip of the nip is fixedly provided on the pedestal.