JPH07276446A - Injection mold device - Google Patents

Abstract

PURPOSE:To eject and retract an ejector pin assuredly by an injection mold device which thrusts out a molded piece from a cavity by using the ejector pin. CONSTITUTION:In an injection mold device consisting of a fixed mold P and a movable mold Q, the movable mold Q is equipped with an ejector plate 11 to be driven by an ejector rod 51 of a molding machine at the time of mold opening and an ejector pin 12 which ejects a molded piece 21 by passing through the movable mold Q and projecting from it in an opened state is fixed on a top 11a of the ejector plate 11. A bottom 11b of the ejector plate is connected to the ejector rod 51. Further, in a return pin 13 which passes through and projects up to a parting line face R of the fixed mold P and the movable mold Q from the top 11a of the ejector plate and is fixed to the top 11a of the ejector plate, a spring is possibly provided subsidiarily in between the top 11a of the ejector plate and a retainer plate 3 arranged in the driving direction of the ejector plate 11 at the time of ejection of the molded piece 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molding die device of a type in which a molded product is separated from the inside of a cavity by using an ejector pin.

[0002]

2. Description of the Related Art As a conventional technique, for example, there is a mold having a two-plate structure having a structure in which a fixed mold S and a movable mold T are divided as shown in FIG. A mold having this structure is often formed by combining a runner and a product, and secondary processing is often performed.

In the fixed side mold S, the fixed side mounting plate 10
A fixed-side mold plate 102 is provided on the front surface (right side in the drawing) of 1. On the fixed side mounting plate 101, a sprue bush 107 having a sprue 107a is formed.
It is attached via 08. Sprue bush 107
A nozzle (not shown) of an injection molding machine can be fitted in the. Further, the fixed side mold plate S is provided with four guide pin bushes 109 (only one is shown), and the movable side mold plate 1
Each of the four guide pins 110 (only one is shown) fixed to 03 is inserted.

In the movable mold T, the movable mounting plate 10
A spacer block 105 is fixed to the front surface (left side in the drawing) of 6, and a receiving plate 104 is provided on the front surface thereof, and a movable side mold plate 103 is further provided on the front surface thereof. An ejector plate 111 is arranged in the space provided by the spacer block 105 between the movable side mounting plate 106 of the movable side mold T and the receiving plate 104. Ejector plate 111
Is composed of two parts, an ejector plate upper part 111a on the parting line surface R side and an ejector plate lower part 111b on the ejector rod 51 side of the molding machine. An ejector pin 112, a return pin 113, and a sprue lock pin 114 are fixed to the ejector plate upper portion 111a. The ejector pin 112 is used for the movable mold plate 10.
It is rotatably supported by the core 115 fixed to 3, and penetrates the movable mold T to reach the cavity 116 formed on the parting line surface R. Return pin 113
Is supported by the movable side mold plate 103 and reaches the parting line surface R. The sprue lock pin 114 is arranged at a position corresponding to the sprue 107a of the sprue bush 107, and the tip end portion is formed in an undercut shape (not shown). A circular space 104a is formed around the return pin 113 in the receiving plate 104, and the upper ejector plate 111a and the movable side mold plate 1 are formed.
A spring 113a is incorporated between the springs 03 and 03.

A through hole 106a of the ejector rod 51 of the molding machine is provided at the center of the movable side mounting plate 106. When the mold is opened (see FIG. 4), the ejector rod 51 projects the ejector plate lower part 111 b, so that the ejector pin 112 causes the molded product 12 in the cavity 116.
1, the sprue lock pin 114 projects the sprue part resin 122, and both pins 112 and 11
The runner 119 is also projected by the projection of No. 4 (see FIG. 5). The molded product 121, the runner 119, and the sprue part resin 122 are chucked and taken out by a molded product take-out robot (not shown) or the like in the protruding state. Then, when the ejector rod 51 is retracted, the ejector plate upper part 111a is returned by the repulsive force of the compressed spring 113a incorporated in the return pin 113, and the ejector pin 112, the sprue lock pin 114, and the return pin 113 are retracted. Was adopted.

[0006]

In the conventional injection molding die device, the ejector pin for ejecting a molded product is moved forward and backward with respect to the parting line surface of the ejector plate. The ejector pin ejection is performed by the ejector rod of the molding machine ejecting the ejector plate and the ejector plate advancing, and the ejector pin retraction operation is such that the ejector rod of the molding machine is pulled away from the ejector plate and the movable side. This is performed by retracting the ejector plate by the repulsive force of a spring incorporated between the ejector plate and the template.

As described above, conventionally, the retracting operation of the ejector pin depends on the repulsive force of the spring. Therefore, if an abnormality occurs in the mold device and the ejector pin is constrained by a force greater than the repulsive force of the spring, the ejector pin will not be retracted, interrupting the molding operation, and in the worst case, the mold. Had a risk of being damaged.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to reliably perform ejecting / pulling-in operations of ejector pins.

[0009]

In order to achieve the above object, the present invention comprises a fixed side mold and a movable side mold,
The movable mold is equipped with an ejector plate that is driven by the ejector rod of the molding machine when the mold is opened.The ejector plate is fixed with ejector pins that project through the movable mold and eject the molded product when the mold is open. In the injection molding die apparatus, the ejector plate is connected to the ejector rod.

Desirably, the return pin, which penetrates from the ejector plate to the parting line surface of the fixed side mold and the movable side mold and is fixed to the ejector plate, is used for ejecting the ejector plate and the molded product. A spring is incorporated between the ejector plate and the template in the drive direction.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the preferred embodiments shown in the accompanying drawings.

FIG. 1 shows an injection molding die apparatus of the present invention. The injection molding die device includes a fixed die P and a movable die Q.
This mold is of a type in which a molded product is molded in a form combined with a runner or the like.

First, the fixed mold P will be described.

The fixed-side mold P is composed of a fixed-side mounting plate 1 and a fixed-side mold plate 2, and the fixed-side mold plate 2 is fixed to the front surface (right side in the figure) of the fixed-side mounting plate 1. . A sprue bush 7 having a sprue 7a is attached to the fixed-side mounting plate 1 via a locate ring 8. A nozzle (not shown) of an injection molding machine can be fitted into the sprue bush 7.

Further, four guide pin bushes 9 (only one is shown) are penetratingly provided on the fixed side mold plate 2, and four guide pins 10 (fixed to the movable side mold plate 3 are fixed. 1
Each of them is shown).

Next, the movable die Q will be described.

The movable side mold Q is composed of a movable side mounting plate 3, a receiving plate 4, a spacer block 5, and a movable side mold plate 6, and the movable side mounting plate 6 has a front surface (on the left side in the drawing). The spacer block 5 is fixed, and the receiving plate 4 is provided on the front surface thereof.
However, the movable side mold plate 3 is further fixed to the front surface thereof.

Movable side mounting plate 6 and receiving plate 4 of movable side mold Q
An ejector plate 11 is arranged in the space provided by the spacer block 5 between the and. The ejector plate 11 includes the ejector plate 11a on the parting line surface R side and the ejector rod 5 of the molding machine.
It is composed of two lower ejector plates 11b on one side. The ejector pin 12, the return pin 13, and the sprue lock pin 14 are provided on the ejector plate 11a.
Is stuck. The ejector pin 12 is a movable mold plate 3
Is supported by the core 15 that is fixed to the movable mold Q.
To reach the cavity 16 formed on the parting line surface R. The return pin 13 is axially supported by the movable side mold plate Q and reaches the parting line surface R. The sprue lock pin 14 is arranged at a position corresponding to the sprue 7a of the sprue bush 7, and the tip portion 14a is formed in an undercut shape.

A window portion 6a penetrating the movable side mounting plate 6 is provided at the center of the movable side mounting plate 6. A support plate 17 is fixed to the central portion of the lower ejector plate 11b on the movable side mounting plate 6 side (right side in the drawing). When the lower ejector plate 11b is in close contact with the movable side mounting plate 6, the support plate 17 is housed in the window portion 6a provided in the movable side mounting plate 6. The support plate 17 is a U-shaped plate, which forms a space 17a between the lower plate 11b of the ejector plate and a through hole 17b at the center thereof, so that the ejector rod 51 of the molding machine can penetrate therethrough. ing.

The ejector rod 51 of the molding machine has a groove 51a formed at its tip. The groove portion 51a of the ejector rod 51 penetrates the window portion 6a of the movable side mounting plate 6 and the through hole 17b of the support plate 17, and the connecting plate 18 and the ejector plate 17 are connected to each other from above in the drawing. It is inserted in a space 17a formed between the lower part 11b and the lower part 11b, and is locked by a comb-shaped locking part 18a formed in the lower part of the connecting plate 18. Therefore, the ejector rod 51 of the molding machine and the ejector plate 11 of the movable die Q are in a connected state. In addition,
Ejector rod 51 and ejector plate 1 of the molding machine
1 means that the connecting and disconnecting can be easily performed by piercing the connecting plate 18.

Next, the operation of this embodiment will be described.

As shown in FIG. 1, in the mold clamped state in which the fixed-side mold P and the movable-side mold Q are combined, the fixed-side mold plate 2
A cavity 16 is formed on a parting line surface R between the movable side template 3 and the mold. Then, the pellets fed from the hopper of the molding machine are advanced by the screw in the cylinder, and the heated and melted molding material forms the runner 19 through the sprue 7a from the nozzle and flows into the cavity 16 from the gate 20. When the molding material in the cavity 16 hardens, the parting line surface R is opened.
Then, the molding material is separated from the nozzle of the molding machine at the sprue 7a, and the molded product 21, the runner 19 and the sprue portion resin 22 remain on the movable side mold plate 3 side. On the other hand, after the opening operation of the parting line surface R is completed, the ejector rod 51 of the molding machine starts the ejecting operation, and the ejector plate 11 connected by the operation of the ejector rod 51 advances. Due to the forward movement of the ejector plate 11, the ejector pin 12, the return pin 13, and the sprue lock pin 14, which are fixed to the ejector plate 11a, are open.
At, the ejecting operation is performed. Ejector pin 12
Protruding the molded product 21, the sprue lock pin 13 protruding the sprue part resin 22, and the pins 12, 14
The runner 19 is also projected due to the protrusion. The molded product 21, runner 19 and sprue part resin 22 are
In the projected state, a molded product take-out robot (not shown) or the like chucks and takes out. Then, when the ejector rod 51 is retracted, the ejector plate upper 11a is returned by the repulsive force of the compressed spring 13a incorporated in the return pin 13, and the ejector pin 12, the sprue lock pin 14, and the return pin 13 are retracted. Was adopted.

In the injection molding die apparatus of this embodiment, the ejector plate 11 to which the ejector pin 12 is fixed is fixed.
Since a and the ejector rod 51 of the molding machine are directly connected to each other, both ejecting and retracting operations of the ejector pin 12 can be reliably performed by the driving force of the ejector rod 51 of the molding machine.

In the present embodiment, an example has been described in which the ejector plate 11 is moved forward and backward, that is, the ejector pin 12 is ejected and retracted only by the driving force of the ejector rod 51 of the molding machine.
The ejector plate 11 is also supplemented by the repulsive force of the spring 113a (see FIG. 3) incorporated between the ejector plate 11 and the movable side mold plate 3 using the return pin 13 as in the conventional example. May be moved forward or backward.

[0025]

According to the configuration of the present invention, in the ejecting and retracting operations of the ejector pin as in the conventional case, the retracting operation is performed by using the return pin inside the movable die and the ejector plate and the movable die. Not only due to the repulsive force of the spring installed between the plate and the ejector pin, but also the retracting action is performed by using the driving force of the ejector rod of the molding machine. Even if an abnormality occurs in the ejector pin and the ejector pin is restrained by a force larger than the repulsive force of the spring, the retracting operation is reliably performed as long as it is not greater than the retracting force of the ejector rod. Therefore,
It also eliminates the risk of interruption of molding work due to abnormal ejector pin retracting operation, and in the worst case, damage to the mold.

[Brief description of drawings]

FIG. 1 is an injection molding die apparatus showing an embodiment of the present invention.

2A and 2B are diagrams showing details of connection between an ejector plate and an ejector rod of a molding machine of the injection molding die device shown in FIG. 1, FIG. 2A being a view seen from above, and FIG. It is the figure seen from the machine side.

FIG. 3 is a view showing a conventional injection molding die device.

FIG. 4 is a view showing a mold open state of the injection molding die device shown in FIG.

5 is a view showing a state where the injection-molding die apparatus shown in FIG. 3 projects a molded product in a mold open state.

[Explanation of symbols]

 P Fixed side mold Q Movable side mold R Parting line surface 11 Ejector plate 12 Ejector pin 13 Return pin 21 Molded product 51 Ejector rod

Claims (2)

[Claims] 1. A fixed-side mold and a movable-side mold, wherein the movable-side mold is provided with an ejector plate driven by an ejector rod of a molding machine when the mold is opened, and the ejector plate includes a mold. In an injection molding die device in which ejector pins for projecting a molded product through the movable mold in an open state are fixed, the ejector plate is connected to the ejector rod. Mold device. 2. The injection-molding die apparatus according to claim 1, wherein the ejecting plate is projecting from the ejector plate to a parting line surface of the fixed-side die and the movable-side die, and is fixed to the ejector plate. An injection molding die apparatus, wherein a spring is incorporated in the return pin between the ejector plate and a mold plate in a driving direction of the ejector plate when the molded product is ejected.