KR20090080301A - Check Member Control Apparatus of Injection Apparatus - Google Patents

Abstract

A check member connection unit of an injection device is provided to remove the operating delay caused by passive movement of the check member. A check member connection unit of an injection device comprises a barrel(2), a screw(3), a check member(5) and an elastic member. The barrel is transferred while the resin is being inserted into. The screw is equipped inside the barrel in order to help the resin to be transferred. The check member is in front of the screw and control the flow of the resin. The elastic member is located at the front of the check member and pushes the check member. One part of the check member is supported with a wing(7a) of a screw head and the other part is supported with check member. The elastic member is made of a coil spring in order to be inserted between a body(4) and the screw head.

Description

Check Member Control Apparatus of Injection Apparatus

The present invention relates to a check member control device of the injection device, and more particularly to prevent the operation delay and malfunction of the check flow prevention check member provided in the screw tip in the barrel constituting the injection device.

In general, the injection device is a device for injecting the resin into the mold manufactured according to the shape of the product to be molded, the mechanical energy of the solid resin particles by the screw rotation installed in the barrel and the heater mounted on the outside of the barrel It is a device that obtains a product of desired shape by injecting and solidifying molten resin into a mold manufactured according to the shape of a product to be melted by thermal energy.

At this time, the screw installed in the barrel is composed of a screw portion for transporting and melting the solid resin granules, and a screw head portion for preventing the back flow of the resin when injecting the molten resin into the mold.

Accordingly, the granulated resin supplied through the hopper is introduced into a barrel equipped with a heater, and shear heat and heater generated in the screw while the screw connected to the hydraulic motor or the electric motor rotate in the barrel. The resin is melted by the heat. The molten resin then passes through the screw head and accumulates at the front end of the head.

At this time, the screw transfers the resin supplied through the hopper in the direction of the screw head while reversing when the molten resin is pressed, so that the resin is continuously transferred to the screw head front end.

It builds up. As the accumulated melt continues to accumulate in the amount specified in the front end of the screw head, when the weighing is completed, the screw stops rotating and advances in the axial direction with the pressure and speed appropriate for the molding conditions and melts through the barrel outlet. The resin is pushed into the mold.

At this time, if the molten resin pushed back in the hopper direction, a deviation insufficient for quantification occurs. In order to solve this problem, injection apparatuses having various molten resin backflow prevention devices have been developed.

In the conventional molten resin backflow prevention device, when the screw finally pushes the quantitative molten resin into the mold, the backflow prevention member itself moves along the axial direction to block the molten resin flow path on the screw head side. Therefore, a small amount of molten resin temporarily flows back to the screw side during the axial movement, which causes a problem in that the deviation is substantially caused in the fixed quantity.

Referring to the conventional molten resin backflow prevention device in more detail through the drawings as follows.

As shown in the accompanying drawings, FIGS. 1A and 1B, the conventional injection apparatus 1 is supplied with water into the barrel 2 through a hopper (not shown) when the screw 3 rotates. Is moved in the direction of the screw head 7 along a flight (threaded) 3a formed in the longitudinal direction of the body portion 4 of the screw 3.

Thereby, the molten resin flows into the passage 5a of the spacer 6 and the check member 5 which is the backflow preventing member, and then flows along the flow path between the blade portions 7a of the screw head 7.

The molten resin that has passed between the check member 5 and the screw head 7 in this way passes through the passage formed between the check member 5 and the spacer 6 and the wing portion 7a of the screw head 7. It gradually accumulates in the front end part 2a of (2), and the back pressure by the melted resin piled up by this is formed. At this back pressure, the screw 3 retreats and fills the quantitative molten resin into the front end portion 2a of the barrel 2, and then stops the screw 3 (the completion of the weighing operation of the molten resin).

Dotted arrows throughout the drawings indicate the flow direction of the molten resin.

On the other hand, for injection of the molten resin, the screw 3 moves forward without being rotated again to push the molten resin in the front end portion 2a of the barrel 2 into the mold through the outlet 2b. At this time, the check member 5 is in contact with the spacer 6 to block the flow path of the molten resin to prevent the reverse flow of the molten resin.

However, in the conventional check member 5, since the timing of blocking the resin can be changed by the viscosity, temperature, etc. of the molten resin, it is impossible to measure the same amount each time.

In other words, when the conventional check member 5 is moved, it is passively moved by the backward of the screw 3, but when the reaction of the check member 5 is not immediate, accurate weighing is difficult.

Furthermore, in the process of stopping the screw 3 and then changing it to the forward movement state, the molten resin, which is compressed and pressed under a high pressure even during a brief stop, has a property of advancing forward, in which case the check member 5 is immediately It is necessary to control the flow of resin by going backward.

By the way, since the conventional check member 5 is moved passively according to the movement of the screw 3 (forward or backward movement), the flow of the resin in the process of changing the movement of the screw 3 may not be interrupted properly, Since the front end of the screw 3 is filled with high-pressure resin, there are many problems in that the movement of the check member 5 (moving state in the screw axial direction) reacts quickly and fails to move.

The present invention is to prevent the phenomenon that the flow control of the resin is not properly made due to the passively moving check member by moving in response to the movement of the screw to ensure that the flow of the resin is surely made.

The solution of the present invention is as follows.

It is made up of a barrel to allow resin to be transported while being melted, a screw provided inside the barrel to allow resin to be transported, and a check member provided to be movable in front of the screw to interrupt the flow of resin. As a structure,

The front of the check member is a structure provided with an elastic member to push the check member.

As such, the present invention has the following effects.

1) It prevents the malfunction of the check member which is hindered by the high pressure resin inside the barrel.

2) Eliminate the operation delay caused by the passive movement of the check member depending on the screw movement.

3) By eliminating the operation delay condition, it has the effect of precise weighing and water area prevention.

In other words, the push member is always pushed by the elastic member supported on the front of the check member which is axially movable at the tip of the screw, so that the screw stops after the backward movement of the screw, and then again without rotation for injection of the resin. When moving forward, there is an effect that the flow can be surely interrupted by reacting immediately during the momentary stop.

Therefore, it can be more effective when performing a precision injection that requires a small amount of weighing precisely.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The same components as in the prior art will be described with the same reference numerals, and detailed description thereof will be omitted, and new components will be described in detail with the new reference numerals.

The present invention, as shown in Figure 2a and 2b, a barrel (2) to be transported while the resin is added and melted, and a screw (3) provided in the interior of the barrel (2) to allow the transfer of the resin is made ) And a check member (5) provided to be movable in front of the screw (3) to control the flow of resin,

The front of the check member 5 is a structure provided with an elastic member 10 to push the check member (5).

One end of the elastic member 10 is supported by the wing portion 7a of the screw head 7, and the other end of the elastic member 10 is provided to be supported by the check member (5).

In addition, the elastic member 10 may be made of a coil spring to be inserted between the body portion 4 and the screw head 7 of the screw (3).

According to the present invention having such a configuration, the solid resin particles are introduced into the barrel 2 by the usual injection operation, that is, the hopper H, and then the screw 3 is turned toward the screw head 7 by the rotation of the screw 3. In the process of melting and injecting the resin in the solid state by the heater (not shown) provided around the barrel 2 and the shear heat of the screw 3, the screw 3 is rotated and retracted. As a result, the check member 5 advances and is brought into contact with the screw head 7 so that the resin injected is accumulated at the front end portion 2a of the barrel 2 via the passage 5a of the check member 5, thereby When all are filled, the screw 3 stops the reverse and rotational motion, and moves forward without rotation.

Here, as shown in Figure 2b, the screw (3) is in the process of changing from the backward and rotational movement to the forward movement in the absence of rotation, a moment of stop occurs, even in this case the present invention the elastic member 10 Since the check member 5 always pushes the check member 5, the check member 5 is moved back and forth immediately during the conversion operation by the forward movement of the screw 3 so as to be brought into close contact with the spacer 6 and to the body part of the screw 3 Blocking the path of the resin melted in (4), which is the only amount of resin discharged through the outlet (2b) of the barrel (2) is introduced into the mold apparatus.

In other words, when the screw 3 is moved forward without stopping after rotation, when the movement of the screw 3 is stopped after the measurement of the resin is made, the physical external force on the check member 5 is also momentarily removed. Since the molten resin, which is compressed and pressurized, has a property of moving forward, accurate weighing may not be achieved, but the check member 5 is always attached to the spacer 6 by the elastic member 10 according to the present invention. By just moving and making close contact, the weighing of the resin can be made accurately.

In this way, the check member 5 does not move quickly in the process of changing the movement of the screw 3 (backward-> stopping-> forward) and fundamentally solves the time delay condition, resulting in inaccurate interruption of the molten resin. This can be prevented.

Therefore, it is possible to prevent the subregional flow due to the pressure of the resin that can occur during the time delay as described above, and to perform a more precise metering.

Although the present invention has been described for the embodiments of the present invention through the accompanying drawings for convenience, it is obvious that various modifications and changes are possible within the scope of the technical idea of the present invention.

Figure 1a is a cross-sectional view showing a state in which the screw of the conventional injection device is rotated and reversed to convey the molten resin toward the front end of the barrel.

FIG. 1B is a cross-sectional view showing an operation of discharging the amount metered by the check member out of the barrel without moving the screw in the state of FIG. 1A.

Figure 2a is a cross-sectional view showing a state in which the screw of the present invention to transport the molten resin toward the front end of the barrel while rotating and backward.

FIG. 2B is a cross-sectional view illustrating an operation of discharging the amount measured by the check member out of the barrel by rotating the screw without rotating the screw in the state of FIG. 2A, wherein the check member is in close contact with the spacer by the repulsive force of the elastic member. The state is shown.

[Code Description in Drawings]

1: Injection device

2: barrel

2a: shear

2b: outlet

3: screw

3a: flight

4 body part

5: check member

5a: passage

6: spacer

7: screw head

7a: wing

Claims (1)

A barrel (2) for the resin to be injected and melted and transported, a screw (3) provided inside the barrel (2) to enable the transfer of the resin, and a movable in front of the screw (3) As a structure consisting of a check member (5) to interrupt the flow of resin, Checking member intermittent device of the injection device, characterized in that the front of the check member 5 is provided with an elastic member 10 to push the check member (5).

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