KR100931798B1 - Injection device with fixed check member - Google Patents

Abstract

The present invention relates to an injection apparatus having a fixed check member, by fixing the check member to the head side of the screw constituting the injection device, and by being pushed through the elastic member, the smooth flow of the molten resin, as well as the reverse flow of the molten resin It is to prevent the.

According to the present invention, the barrel (2) to which the resin is supplied, the screw (3) for conveying the resin supplied and provided in the barrel (2), and the check to be in close contact with and fixed to the screw head (7) side of the screw (3) A member 10 and an elastic member 20 fixed and installed inside the barrel 2 while allowing the screw head 7 to pass therethrough are supported by the check member 10.

According to the present invention having the configuration, the check member is fixed to the screw and the elastic member is supported on the front of the screw head so that the smooth transfer is possible during the feeding of the molten resin, and after the metering is performed, the molten resin during the forward movement of the screw for injection. Has the effect of preventing backflow.

Description

Injection device with fixed check member {Injection Apparatus with Fixting Type Check Member}

The present invention relates to an injection apparatus having a fixed check member, and more particularly, by fixing the check member to the head side of the screw constituting the injection device, and being carried through the elastic member, as well as smoothly feeding the molten resin, This is to prevent the reverse flow of the molten resin.

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.

The molten resin backflow prevention device of a conventionally developed plastic injection device is disclosed in FIGS. 1 and 2.

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.

The prior art will be described in more detail with reference to the accompanying drawings.

1 and 2, in the conventional injection apparatus 1, when the screw 3 rotates, the water support material supplied into the barrel 2 through the hopper H is screwed. It is moved in the direction of the screw head 7 along the flight (threaded) of (3).

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

The molten resin that has passed between the check ring 5 and the screw head 7 in this way is the front end of the barrel 2 through a flow path formed between the check ring 5 and the spacer 6 and the screw head 7. It builds up gradually in (2a), 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).

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 ring 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 case of the check ring 5, it has a section moving in the axial direction when the flow path of the molten resin is blocked, and as a result, it is possible to prevent the molten resin from flowing backward by the volume of the product of the moving section and the flow path cross-sectional area. In addition, since the timing at which the check ring 5 is interrupted can be changed by the viscosity, temperature, etc. of the molten resin, it is impossible to measure the same amount each time.

In addition, since the check ring 5 is moved, if the machined surface of the check ring 5 is not smooth or the coating state is abnormal, the resin may be stagnant, causing problems such as carbonization of the resin or gas stagnation. .

Furthermore, since the check ring 5 moves to the left and right, a phenomenon in which the check ring 5 is damaged or the coating surface of the check ring 5 is peeled off due to repeated collision with the screw head 4 and the spacer 6. There was also a problem that occurred.

In addition, as described above, since the check ring 5 is typically provided with a size of about 1-2 times the screw diameter, it takes up as much space. Therefore, since the formation area of the flight (screw acid) of the screw, which allows the resin to be melted and mixed, should be reduced by the length of the check ring 5, there is also a problem that it is a major cause of the pressure rise of the screw tip. .

Accordingly, the present invention has been invented to solve the conventional problems as described above, by fixing the check member to the head side of the screw constituting the injection device, and by being carried through the elastic member, as well as smooth feeding of the molten resin, This is to prevent the reverse flow of the molten resin.

The problem solving means of the present invention, in order to solve the above-mentioned conventional problems, the screw is supplied, the screw for feeding the supplied resin provided in the barrel, the screw head side of the screw is fixed and fixed It is provided with a check member, and an elastic member that is fixed to the inside of the barrel while allowing the screw head to pass through to be carried on the check member.

The check member has a structure in which a plurality of passage grooves are opened and closed by the elastic member in the circumferential direction.

One end of the elastic member is a structure that is supported by the support jaw formed in the barrel.

In addition, the front of the elastic member may have a structure that is fixed to the blocking member for opening and closing the through groove of the check member.

According to the present invention, the check member is fixed to the screw and the elastic member is held in front of the screw head so that the smooth conveying is possible when the molten resin is pumped. It is effective to avoid.

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.

3 is a cross-sectional view showing an injection apparatus according to the present invention. As shown in the drawing, in the present invention, as in the prior art, a resin supporting material is supplied into the barrel 2 and heated and melted by a heater (not shown) provided on the outer surface of the barrel 2. The screw (3) is pushed toward the front end portion (2a) of the barrel (2), at which time the screw (3) is rotated backwards to secure the space of the front end portion (2a) to collect the molten resin .

Arrows indicated by dotted lines in the figure indicate the movement of the resin, and arrows indicated by thick solid lines indicate the backward movement of the screw (3).

Here, the present invention has a structure in which the check member 10 is fixed to one surface of the screw head 7 as shown in FIG. 6.

The check member 10 has a plurality of passage grooves 10a formed along the circumferential direction. The molten resin that is pushed through the passage groove 10a passes and collects at the front end portion 2a of the barrel 2.

In addition, the front shear portion 2a of the screw head 7 has a structure in which the elastic member 20 is fixed and installed to be in contact with the check member 10. In other words, it is supported to open and close the passage groove (10a) of the check member (10).

The elastic member 20 may have a coil spring structure. However, the present invention is not limited thereto and may have various other forms.

At one end of the elastic member 20, that is, at the inner circumferential surface of the front end portion 2a of the barrel 2, a support jaw 2c is formed so that one end of the elastic member 20 is supported and the elastic member 20 is supported. The other end is supported by the check member 10 fixed to the screw head 7 side.

In addition, the front of the elastic member 20, as shown in Figure 7, the fixing member 21, it can be installed to enable opening and closing the passage groove (10a) of the check member (10).

The blocking member 21 may be formed in a circular shape to match the shape of the barrel 2, and a through hole 21a is formed to allow the screw head 7 to pass therethrough.

The present invention having such a configuration, the water support material is supplied to the inside of the barrel (2) for a normal injection operation, and then the screw (3) is rotated while moving backwards, the molten resin is pressed in close contact with the screw head (7), After passing through the passing groove (10a) of the fixed check member 10 is collected at the front end portion (2a) of the barrel (2), after the measurement of the molten resin, the screw (3) stops the rotation and stops, and then advances While moving, the molten resin collected at the front end portion 2a of the barrel 2 is ejected out of the outlet 2b of the barrel 2, transferred to the mold apparatus, and filled in the cavity of the mold apparatus.

The molten resin passing through the passage groove (10a) of the check member 10 is pressurized with a predetermined pressure, the front end portion of the elastic member 20 is larger than the elastic force of the elastic member 20 before being compressed By pushing the opening 10a of the check member 10 to open, the molten resin can move through.

As described above, the molten resin is collected at the front end portion (2a) of the barrel (2), the injection movement of the molten resin is performed by the forward movement of the screw (3), the screw head 7 toward the elastic member 20 Is touched against the check member 10, and the elastic member 20 is compressed as the screw 3 moves forward.

Therefore, as the elastic member 20 is compressed, the stronger repulsion force and the forward moving force of the screw 3 are added, so that the front end portion of the elastic member 20 comes into close contact with the check member 10, The through groove 10a is blocked. Accordingly, when discharging the molten resin gathered in the front end portion 2a, the molten resin flows backward by the back pressure, thereby preventing the phenomenon of passing through the passage groove 10a of the check member 10 again.

The screw head 7 may have a passage through which molten resin can pass, as in the prior art, but may not have a passage.

In addition, the front of the elastic member 20 may have a structure in which the blocking member 21 is fixed so that the through member 10a of the check member 10 can be opened and closed more effectively by the blocking member 21. It is possible to prevent the backflow of the molten resin during the injection operation.

Although the present invention has been described for convenience of the present invention with reference to the accompanying drawings, it is obvious that various modifications and changes can be made within the scope of the technical idea of the present invention.

1 is a cross-sectional view showing a conventional injection apparatus.

2 is a cross-sectional view showing a state in which the screw of the conventional injection device is moved forward for the injection of the resin.

Figure 3 is a cross-sectional view showing the injection device of the present invention shows a state that the resin is conveyed by the rotation and backward of the screw.

Figure 4 is a cross-sectional view showing a state in which the resin of the injection device of the present invention is pressed and moved while pushing the elastic member past the check member.

Figure 5 is a cross-sectional view showing a state in which the screw is moved forward for the injection operation of the resin in the injection device of the present invention.

6 is a cross-sectional view showing the check member of the present invention.

Figure 7 is a cross-sectional view showing a state in which the blocking member is provided on the front of the elastic member as another embodiment of the present invention.

FIG. 8 is a cross-sectional view showing a state in which the resin is pressed and moved while exporting the elastic member through the check member in the state of FIG. 7.

FIG. 9 is a cross-sectional view illustrating a state in which a screw is moved forward to compress the elastic member in order to inject the pressed resin in the state of FIG. 8.

[Code Description in Drawings]

1: Injection screw

2: barrel

2a: shear

2b: outlet

2c: support jaw

3: screw

5: check ring

5a: passage

6: spacer

7: screw head

10: check member

10a: Passing groove

20: elastic member

21: blocking member

21a: through hole

Claims (4)

A barrel 2 to which resin is supplied, A screw 3 for conveying the resin supplied and provided in the barrel 2, The check member 10 is in close contact with and fixed to the screw head 7 side of the screw 3, Injection with a fixed check member, characterized in that it is provided with an elastic member 20 which is fixed and installed inside the barrel 2 to allow the screw head 7 to pass through to be held by the check member 10. Device. The method according to claim 1, The check member 10 is injection device having a fixed check member, characterized in that a plurality of passage grooves (10a) are opened and closed by the elastic member 20 in the circumferential direction. The method according to claim 2, One end of the elastic member 20, the injection device having a fixed check member, characterized in that the supporting jaw (2c) formed in the interior of the barrel (2). The method according to claim 2 or 3, Injection device having a fixed check member, characterized in that the blocking member 21 is fixed to the front of the elastic member 20 to open and close the through groove (10a) of the check member (10).

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