JP2004106354A - Ejector mechanism for injection molding mold - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ejector mechanism for an injection molding mold, which can improve the difficulty of controlling an outside diameter of an ejector pin, a return failure and a leakage of a fluid by using a magnetic force as a driving force for the ejector pin and without using the fluid. <P>SOLUTION: In this ejector mechanism for the injection mold, a permanent magnet 16 is installed in a flange part, on the other side of a molding 1, of the ejector pin 3; an electromagnet 17 is installed in each place corresponding to the ejector pin 3 inside a base plate 7; a groove 18 for wiring is formed in the base plate 7 so that the electromagnet 17 and a controller 19 can be connected together; and a spring 11 for returning the ejector pin 3 in the reverse direction by making one end abut on the permanent magnet 16 serving as the flange part of the ejector pin 3 is installed in a space 10 of a core 2. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a projection mechanism of an injection mold used for an injection molded product such as plastic.
[0002]
[Prior art]
In general, in a conventional ejection mechanism of an injection molding die, a mechanism in which a plate in which ejection pins are incorporated is pushed out by an ejection rod on a molding machine side is mainly used.
[0003]
FIG. 4 shows a conventional ejection mechanism of an injection molding die. In FIG. 4, 1 is a molded product, 2 is a core, 3 is an ejection pin, 4 is an upper ejector plate, and 5 is a lower ejector plate. , 6 is a base, 7 is a base plate, 8 is a table, and 9 is an ejector rod. In the conventional ejection mechanism of the injection mold, the ejector rod 9 built in the molding machine moves forward after the mold is opened, ejects the upper ejector plate 4 and the lower ejector plate 5, and moves with the upper ejector plate. The ejection pin 3 attached to the plate 4 and the lower ejector plate 5 moves forward to eject the molded product 1.
[0004]
On the other hand, FIG. 5 shows a protruding mechanism using a fluid which has already been filed. In this mechanism, instead of the ejector rod 9 and the upper ejector plate 4 and the lower ejector plate 5 shown in FIG. 4, flow paths 12 and 13 to which a pressurized fluid is supplied are formed in the base plate 7, and the core 2 A space 10 for accommodating the protruding pin 3 is provided therein, and O-rings 14 and 15 for preventing leakage of fluid are provided at a joint of the core 2 and the base plate 7. By supplying the pressurized fluid to the flow path 12 via the flow path 13, the push-out pin 3 moves forward to project the molded article 1. In FIG. 5, reference numeral 11 denotes a spring for returning the push-out pin 3 to a position before the push-out.
[0005]
[Problems to be solved by the invention]
However, as described above, in order to apply pressure by a fluid as a driving force of the ejection pin 3, O-rings 14 and 15 for preventing leakage of the fluid must be provided. There is a risk that the outer diameter of the O-ring may become difficult to control, the protrusion pin 3 may return poorly due to the resistance of the O-ring 14, or the O-ring 15 may be leaked due to incomplete sealing.
[0006]
Accordingly, the present invention has been made in view of the above-described circumstances, and the present invention provides an injection molding method that uses a magnetic force as a driving force of a protrusion pin and does not use a fluid, thereby improving the difficulty in controlling the outer diameter of the protrusion pin, poor return, and leakage of fluid. An object of the present invention is to provide a mechanism for projecting a metal mold.
[0007]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, in the invention according to claim 1, in a projecting mechanism of an injection molding die for projecting a projecting pin from a core and releasing a molded product, a space for accommodating the projecting pin in the core is provided. At the same time, a magnet is installed on the protruding pin, a magnetic force generator is installed in the injection mold, a controller that supplies a current to the magnetic force generator is arranged outside the mold, and a current is applied to the magnetic force generator. The most important feature is a projection mechanism of an injection mold which has means for generating a magnetic force by applying the voltage and driving the projection pin.
[0008]
According to the second aspect of the present invention, a main part of the ejection mechanism of the injection mold according to the first aspect is provided with a spring for urging the ejection pin back in a direction opposite to the ejection direction inside the space. I do.
[0009]
According to the third aspect of the present invention, the controller disposed outside the mold is provided with a function of applying a current in a direction opposite to a current direction applied when the ejection pin is ejected, so that the ejection pin is returned not only in the ejection direction but also in the return direction. The main feature of the present invention is a projection mechanism of an injection mold according to claim 1 or 2 which can be biased to the above.
[0010]
According to the fourth aspect of the present invention, by further arranging a magnetic force generating device in a space on the side of the protruding direction of the protruding pin in the mold and performing control opposite to that of the magnetic force generating device performing the protruding operation, The main feature is the ejection mechanism of the injection mold according to any one of claims 1 to 3, which is configured to obtain a strong ejection force.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 and FIG. 2 show an example of an embodiment of the present invention. In the figure, portions denoted by the same reference numerals as those in FIG. 5 represent the same components. This embodiment is the same as the first embodiment, except that the system for driving the protruding pin 3 is changed to a system for driving by a magnetic force instead of a fluid, as shown in FIGS. .
[0012]
In the case of the illustrated example, a permanent magnet 16 is provided on a flange portion of the protruding pin 3 on the side opposite to the molded product 1, and a coil capable of generating a magnetic force by an electric current in each of the locations inside the base plate 7 corresponding to the protruding pin 3. An electromagnet 17 such as a magnet is provided, and a wiring groove 18 is formed in the base plate 7 so that the electromagnet 17 and the controller 19 can be connected. Further, a flange 10 of the protruding pin 3 is formed in the space 10 of the core 2. One end of the spring 11 is brought into contact with a permanent magnet 16 as a part, and a spring 11 for returning the protruding pin 3 in the reverse direction is provided.
[0013]
Accordingly, when the mold is opened and the projecting process is performed during the molding process of the molded product 1, a current flows from the controller 19 to the electromagnet 17, and as shown in FIG. A repulsive force 20 is generated, and the ejection pin 3 moves forward (upward in the figure), so that the molded product 1 can be ejected.
[0014]
In this way, by using the magnetic force as the driving force of the protruding pin 3 and not using the fluid, it is possible to improve the difficulty in controlling the outer diameter of the protruding pin 3, poor return, and leakage of the fluid.
[0015]
FIG. 3 shows another example of the embodiment of the present invention. In the space 10 of the core 2, another electromagnet 21 is disposed at a position opposite to the electromagnet 17 in the space 10, and the electromagnet 21 is placed first. The control can be performed such that a magnetic field completely opposite to the above-described electromagnet 17 is generated.
[0016]
In the example shown in FIG. 3, since the electromagnet 17 generates a repulsive force against the permanent magnet 16 and at the same time, the electromagnet 21 generates a attracting force with the permanent magnet 16. It can be carried out.
[0017]
In addition, the protrusion mechanism of the injection mold of the present invention is not limited to the illustrated example described above, and it goes without saying that various changes can be made without departing from the scope of the present invention.
[0018]
【The invention's effect】
As described above, according to the protrusion mechanism of the injection mold according to claims 1 to 4 of the present invention, the following excellent effects can be obtained.
[0019]
According to the projection mechanism of the injection mold according to the first aspect of the present invention, since no fluid is used unlike the related art, there is no fear that the fluid leaks, and the O-ring or the like does not need to be installed. No frictional resistance occurs. Therefore, the outer diameter management becomes very simple. Also, there is no return failure of the protruding pin due to frictional resistance. Furthermore, there is no fear of leakage because the fluid itself is not used.
[0020]
According to the ejection mechanism of the injection molding die according to the second aspect of the present invention, after the ejection pin is ejected by placing the spring in the space, the current of the controller is cut off by the pressure of the spring when the current is cut off from the controller. The ejection pin can be quickly returned to the position before the ejection.
[0021]
According to the ejection mechanism of the injection molding die according to the third aspect of the present invention, by attaching a mechanism for changing the direction of the current applied to the controller, the direction of the current is reversed at the end of the ejection. The repulsive force becomes the opposite attractive force and attracts the permanent magnet, so that the ejecting pin can be quickly returned to the position before the ejecting.
[0022]
According to the ejection mechanism of the injection molding die according to the fourth aspect of the present invention, a stronger and more reliable ejection can be performed by the magnetic force generator performing the operation opposite to the magnetic force generator performing the ejection operation.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an example of an embodiment of the present invention.
FIG. 2 is a cross-sectional view showing a state at the time of protrusion in an example of an embodiment of the present invention.
FIG. 3 is a cross-sectional view of another example of an embodiment of the present invention.
FIG. 4 is a cross-sectional view showing a conventional ejection mechanism of an injection mold.
FIG. 5 is a sectional view showing a projecting mechanism using a fluid.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Molded product 2 Core 3 Protruding pin 4 Upper ejector plate 5 Lower ejector plate 7 Base plate 9 Ejector rod 10 Space 11 Spring 16 Permanent magnet 17 Electromagnet 18 Groove 19 Controller 20 Repulsive force 21 Electromagnet

Claims (4)

In the ejection mechanism of an injection molding die for ejecting a protruding pin from a core to release a molded product, a space for accommodating the ejection pin is provided in the core, and a magnet is provided on the ejection pin, and the ejection pin is provided. A means for installing a magnetic force generating device inside a mold, arranging a controller for supplying a current to the magnetic force generating device outside the mold, generating a magnetic force by applying a current to the magnetic force generating device, and driving the protrusion pin A projection mechanism for an injection mold, comprising: 2. The ejection mechanism for an injection mold according to claim 1, further comprising a spring provided in said space to urge the ejection pin back in a direction opposite to the ejection direction. The controller arranged outside the mold has a function of applying a current in a direction opposite to a current direction applied when the protrusion pin is protruded, so that the protrusion pin can be urged not only in the protrusion direction but also in a return direction. 3. The protrusion mechanism of the injection mold according to 1 or 2. A further magnetic force generating device is arranged in a space on the side of the protruding direction of the protruding pin of the mold, and is controlled to perform an operation opposite to the magnetic force generating device performing the protruding operation, thereby obtaining a stronger protruding force. A projection mechanism for the injection mold according to claim 1.

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