KR102276619B1 - Hot runner injection molding apparatus for injection with constant volume and pressure - Google Patents

Abstract

The present invention relates to a hot runner injection mold apparatus, and in particular, the molten resin of the injection machine is filled and stored in a molten resin storage cylinder (41) communicating with the cavity (14) of the mold at a predetermined amount and a predetermined pressure, and then stored in the cavity of the mold. (14) When closing, in conjunction with the closing operation, the plunger 50 moves from the maximum backward position to the maximum forward position of the inner space 42 of the molten resin storage cylinder 41. 42), the molten resin stored in the mold is discharged to the cavity 14 of the mold with a positive static pressure.

Description

Hot runner injection molding apparatus for injection with constant volume and pressure

The present invention relates to a hot runner injection molding apparatus, and more particularly, to a hot runner injection molding apparatus capable of injecting a constant amount of molten resin at a constant pressure into a cavity of a mold.

Recently, a hot runner injection mold device has been widely used as a plastic injection mold. As such a hot runner injection mold apparatus, those disclosed in the following patent documents are generally widely known. In the case of the conventional hot runner injection mold apparatus disclosed in Patent Document 1, the molten resin discharged at a constant pressure from the nozzle of the injection machine passes through the sprue of the mold, the runner of the manifold, and the resin passage of the valve body in turn, just before the gate of the mold. At the moment of the closing of the mold, the gate is opened by retracting the valve pin that closed the gate, and the molten resin of the resin passage is injected into the cavity of the mold through the opened gate.

In the case of the conventional hot runner injection mold described above, when the molten resin is discharged from the injection machine, the molten resin is supplied to the cavity by the discharge pressure generated by the injection machine, so the distance from the sprue, which is the injection port, to the gate is relatively long. In this case, a pressure loss occurs during the flow from the sprue to the gate, resulting in a problem that the filling pressure in the cavity is not sufficient. In the case of a conventional hot runner injection mold to compensate for such a pressure loss, the injection pressure must be increased in the injection machine. If the injection pressure is increased, the clamping force must be increased, so that the mold size is increased.

In addition, in the case of multi-gates with different distances from the sprue to each gate, the filling pressure of the cavity is not constant according to the flow distance of the melt from the sprue to the gate, and accordingly, the filling amount of the melt in the cavity is also not constant There was a problem that caused injection defects as the

And, in the case of the conventional hot runner injection mold, the so-called cycle time required for a series of processes from injection of the molten resin to filling the cavity is the so-called cycle time, since the mold is closed and then the molten resin is injected from the injection machine to fill the cavity. As the time for the molten resin injected from the valve to reach just before the gate at the tip of the valve body (the time taken until just before the molten resin is injected into the cavity) becomes longer, the overall cycle time is lengthened.

KR 10-2018-0101993A KR 10-0925280B1

Therefore, the present invention solves the disadvantages of the conventional hot runner injection mold apparatus, and it is possible to fill the cavity with a predetermined amount of molten resin at a constant pressure without being affected by the distance of the resin passage from the injection machine to the gate. An object of the present invention is to provide a hot runner injection mold apparatus for discharging positive static pressure.

On the other hand, another object of the present invention is to provide a hot runner injection mold apparatus for quantitative static pressure discharge that can shorten the overall cycle time by reducing the idle time required for the molten resin extruded from the injection machine to reach the tip of the valve body of the mold. have.

The present invention for achieving the above object,

an upper fixing plate installed with a sprue into which the molten resin extruded from the injection machine is introduced; a manifold having a resin passage for dispensing the molten resin extruded from the injection machine; an upper mold block having a gate and being spaced apart from the upper fixed plate by a certain gap or moving to approach the upper fixed plate; a lower mold block that forms a cavity together with the upper mold block, closes the cavity when combined with the upper mold block at the lower side of the upper mold block, and opens the cavity when separated from the upper mold block; and a valve body having an internal resin passage and installed on the upper mold block so that the gate and the resin passage of the manifold communicate with each other through the internal resin passage.

Having an internal space of a certain volume, the internal space communicates with the resin passage of the manifold through the inlet port of the side wall, and communicates with the inner passage of the valve body through the outlet port, so that the resin when the cavity is opened a molten resin storage cylinder for accommodating and storing the molten resin of the injection machine provided through the passage by a predetermined volume; and

In the inner space of the molten resin storage cylinder, it is installed to reciprocate between a maximum backward position forming the maximum volume of the molten resin storage cylinder and a maximum forward position forming the minimum volume of the molten resin storage cylinder, When the lower mold block is in close contact with the upper mold block to close the cavity, the molten resin stored in the molten resin storage cylinder is discharged into the cavity through the gate in conjunction with the operation of the upper mold block, and conversely, the lower mold When the block is separated from the upper mold block and the cavity is opened, the plunger moves backward to the maximum reverse position and stores the molten resin by inflowing the maximum volume into the inner space.

When the lower mold block is spaced apart from the upper mold block to open the cavity, the plunger is placed in the maximum backward position, and when the lower mold block is in close contact with the upper mold block to close the cavity, the plunger is placed in the maximum forward position and a plunger actuator for operating the plunger in conjunction with the forward/reverse motions of the lower mold block and the upper mold block.

In addition, the present invention,

A manifold having a resin passage for dispensing the molten resin extruded from the injection machine, an upper mold block having a gate, and forming a cavity with the upper mold block and closing the cavity when closely coupled to the upper mold block, A valve body having a lower mold block that opens the cavity when separated from the upper mold block, and an inner passage connected to one side of the resin passage of the manifold and coaxially communicating with the gate of the upper mold block; It is provided to move between the upper limit and the lower limit in the inner passage of the valve body along the central axis direction of the inner passage, and when it is located at the lower limit, the lower end closes the gate of the upper mold block, and when it is located in the upper limit position, A hot runner injection molding apparatus having a valve pin at a lower end for opening the gate, a valve pin actuator for operating the valve pin so that the valve pin moves between upper and lower limits, and an upper fixing plate on which the valve pin actuator is installed In

An injection machine having an inner space, an inlet port connecting the inner space and the resin passage of the manifold on a side wall, and an outlet port connecting the inner space to a gate at the other side, provided through the resin passage a molten resin storage cylinder for accommodating and storing the molten resin of the predetermined volume; and

It is fixed to the upper fixed plate and is installed so as to be reciprocally movable between a maximum backward position forming a maximum volume in the molten resin storage cylinder and a maximum forward position forming a minimum volume, and when retracted to the maximum backward position, the By opening the inlet port of the melt storage cylinder, the molten resin in the resin passage is filled as much as the maximum volume of the melt storage cylinder, and when moving from the maximum reverse position to the maximum forward position, the inlet port is closed so that the molten resin in the resin passage It is characterized in that it includes a plunger that blocks the inflow into the inner space of the molten resin storage cylinder and at the same time discharges the molten resin stored in the molten resin storage cylinder by a certain volume.

The plunger actuator is coupled to the upper end of the plunger, and one end is rotatably coupled to the hinge pin on the upper plate of the mold, and an operation lever for moving the plunger up and down while turning around the hinge pin by a predetermined angle. ;

a connecting rod having one end connected to one side of the lower mold block so as to linearly reciprocate in conjunction with the opening and closing operation of the cavity of the lower mold block;

One side is connected to the upper plate of the mold so as to be able to pivot around the center pin, and one end is connected to the operation lever and the other end is connected to the front end of the connecting rod, and the center pin is interlocked with the linear reciprocating motion of the connecting rod. and a link bar for moving the actuating lever in the vertical movement direction of the plunger while turning to the center.

The valve pin actuator includes: a valve cylinder having an inner space and having first and second passages for introducing or outflowing a working fluid into the inner space, the valve cylinder being installed on the upper fixed plate; By coupling the upper end of the valve pin to the bottom surface and dividing the inner space of the valve cylinder into the upper piston chamber in which the first flow passage communicates and the lower piston chamber in which the second passage communicates, the working fluid is selectively applied to the upper piston chamber or the lower piston chamber. It is composed of a piston mechanism including; a piston that closes or opens the gate with a valve pin while moving forward or backward in the inner space of the valve cylinder as it flows into the valve.

The plunger actuating mechanism includes fixing the upper end of the plunger to the upper fixed plate on which the valve cylinder is fixedly installed, and the valve pin is not affected by the operation of the plunger and operates only by the piston mechanism. It consists of a plunger holder through which it is penetrated.

As the upper mold block moves toward the upper fixed plate in a state in which the lower mold block moves and closes the cavity, the molten resin storage cylinder moves so that the plunger moves relative to the maximum forward position. Conversely, the lower mold block As the upper mold block moves in a direction away from the upper fixed plate in a state in which the cavity is opened by this movement, the molten resin storage cylinder is moved so that the plunger moves relative to the maximum reverse position. .

According to the present invention described above, the cavity can be filled with a predetermined amount of molten resin at a constant pressure without being affected by the distance of the resin passage from the injection machine to the gate, so that an injection product of uniform quality can be molded. .

According to the present invention, the overall cycle time can be shortened by reducing the idle time required for the molten resin extruded from the injection machine to reach the tip of the valve body of the mold, thereby improving productivity.

1 is a view of an injection mold apparatus according to a first embodiment of the present invention, and is a view in a state in which a cavity is opened.
2A is an operation state diagram of the injection mold apparatus according to the first embodiment of the present invention, and is a view showing an operation state of storing a predetermined amount of molten resin in a molten resin storage cylinder.
FIG. 2B is an operation state diagram of the injection mold apparatus according to the first embodiment of the present invention. Following the operation state shown in FIG. 2A, an operation state of discharging a predetermined amount of molten resin from the molten resin storage cylinder into the cavity. It is a drawing that shows
3A is a view showing the operating state of the injection mold apparatus according to the second embodiment of the present invention, and is a view showing the operating state of storing a predetermined amount of molten resin in a molten resin storage cylinder.
3B is a view showing an operating state of an injection mold apparatus according to a second embodiment of the present invention. Following the operating state shown in FIG. 3A, a predetermined amount of molten resin is discharged into a cavity in a molten resin storage cylinder. It is a drawing showing the working state.
4A is a view showing an operating state of an open gate injection mold apparatus according to a third embodiment of the present invention, and is a view showing an operating state of storing a predetermined amount of molten resin in a molten resin storage cylinder.
4B is a view showing an operating state of an injection mold apparatus according to a third embodiment of the present invention. Following the operating state shown in FIG. 4A, a predetermined amount of molten resin is discharged into a cavity in a molten resin storage cylinder. It is a drawing showing the working state.

Hereinafter, a preferred embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

<First embodiment>

In the injection mold apparatus according to the first embodiment of the present invention, as shown in FIGS. 1, 2A and 2B, the upper fixing plate on which the sprue 18 into which the molten resin extruded from the injection machine (not shown) is introduced is installed. (61), a manifold 15 having a resin passage 16 for distributing the molten resin extruded from the injection machine, and a gate 12 are provided, and spaced apart from the upper fixed plate 61 by a certain gap or upper The upper mold block 11 moving close to the fixed plate 61, the cavity 14 is formed together with the upper mold block 11, and the upper mold block 11 is located below the upper mold block 11. ) and a lower mold block 13 that closes the cavity 14 when combined, and opens the cavity 14 when separated from the upper mold block 11 .

Then, the valve body 21 is installed in the upper mold block 11 . The valve body 21 has an inner passage 22 to which the resin passage 16 of the manifold 15 is connected and coaxially communicated with the gate 12 of the upper mold block 11 . The valve pin 23 is installed to move between the upper limit and the lower limit in the inner passage 22 of the valve body 21 along the central axial direction of the inner passage 22 .

The valve pin 23 moves between the upper limit and the lower limit by the operation of the valve pin actuator. When the valve pin 23 is positioned at the lower limit, the lower end closes the gate 12 of the upper mold block 11 , and when positioned at the upper limit position, the lower end opens the gate 12 .

A valve pin actuator for operating the valve pin 23 so that the valve pin 23 moves between the upper and lower limits is provided on the upper fixing plate 61 .

The valve pin actuator has an internal space, and has a first flow path 62b and a second flow path 62a for introducing or outflowing a working fluid into the internal space, and a valve cylinder installed on the upper fixed plate 61 ( 71) and; A lower piston connecting the upper end of the valve pin 23 to the bottom surface and the upper piston chamber 72a through which the first passage 62b communicates with the inner space of the valve cylinder 71 and the second passage 62a communicates with each other. It is partitioned by the seal 72b, and as the working fluid selectively flows into the upper piston chamber 72a or the lower piston chamber 72b, it moves forward or backward in the internal space of the valve cylinder 71 while using the valve pin 23 to the gate ( 12) to close or open the piston (75); is composed of a piston mechanism including.

As shown in FIG. 1, the injection mold apparatus of the present invention includes a fixed-quantity and positive-pressure discharge mechanism for receiving and storing a predetermined amount of molten resin and then discharging the molten resin to a cavity at a constant pressure by a predetermined amount. Such a fixed-quantity and positive pressure discharge mechanism has a configuration including a molten resin storage cylinder (41) and a plunger (50) for pushing out the molten resin stored in the molten resin storage cylinder (41).

The molten resin storage cylinder 41 has an inner space 42, and an inlet port 43 connecting the inner space 42 and the resin passage 16 of the manifold 15 is provided on the side wall, An outlet port for connecting the inner space 42 to the gate 12 is provided on the other side, and the molten resin of the injection machine provided through the resin passage 16 is accommodated and stored by a predetermined volume.

The plunger 50 has an upper portion 51 fixed to the upper cover plate 17 through a plunger holder 81 . The plunger 50 is installed to be reciprocally movable between a maximum backward position forming a maximum volume and a maximum forward position forming a minimum volume within the inner space 42 of the molten resin storage cylinder 41 .

As shown in FIG. 2A , when the plunger 50 retracts to the maximum retracted position, the inlet port 43 of the molten resin storage cylinder 41 is opened to melt the molten resin in the resin passage 16 . The maximum volume is filled in the internal space 42 of the resin storage cylinder 41 .

As shown in FIG. 2B, as the upper cover plate 17 moves in close contact with the lower surface of the upper fixing plate 61, the plunger 50 moves from the maximum backward position to the maximum forward position, molten resin is stored By closing the inlet port 43 of the cylinder 41, the molten resin in the resin passage 16 of the manifold 15 is blocked from flowing into the inner space of the molten resin storage cylinder 41, and at the same time, the molten resin storage cylinder The melted resin stored in (41) is discharged into the cavity (14) by a certain volume.

As described above, in the injection mold apparatus of the present invention, the molten resin extruded from the injection machine is stored in the molten resin storage cylinder 41 of a certain volume and then discharged to the cavity as much as the stored volume at a constant pressure, so there is always a certain amount of molten resin is injected into the cavity with a constant pressure to mold a product of uniform quality.

<Second embodiment>

In the injection mold apparatus according to the second embodiment of the present invention, as shown in FIGS. 3A and 3B, a sprue 18 into which molten resin extruded from an injection machine (not shown) is introduced is installed, and the sprue 18 ) a manifold 15 having a resin passage 16 for distributing the molten resin provided through, an upper mold block 11 having a gate 12, and a cavity with the upper mold block 11 ( 14), closing the cavity 14 when combined with the upper mold block 11 from the lower side of the upper mold block 11, and closing the cavity 14 when separated from the upper mold block 11 14) and a lower mold block 13 for opening it.

The valve body 21 is installed in the upper mold block 11 . The valve body 21 has an inner passage 22 to which the resin passage 16 of the manifold 15 is connected and coaxially communicated with the gate 12 of the upper mold block 11 . The valve pin 23 is installed to move between the upper limit and the lower limit in the inner passage 22 of the valve body 21 along the central axial direction of the inner passage 22 .

The valve pin 23 moves between the upper and lower limits. When the valve pin 23 is positioned at the lower limit, the lower end closes the gate 12 of the upper mold block 11 , and when positioned at the upper limit position, the lower end opens the gate 12 .

The valve pin 23 moves between the upper limit and the lower limit in association with the operation of a plunger actuator to be described later, and the plunger actuator that operates the valve pin 23 is provided on the upper fixing plate 61 .

As shown in FIGS. 3A and 3B , the injection mold apparatus according to the second embodiment includes a fixed-quantity and positive-pressure discharge mechanism for receiving and storing a predetermined amount of molten resin and then discharging the molten resin to a cavity at a constant pressure by a predetermined amount. Such a fixed-quantity and positive pressure discharge mechanism has a configuration including a molten resin storage cylinder (41) and a plunger (50) for pushing out the molten resin stored in the molten resin storage cylinder (41).

The molten resin storage cylinder 41 has an inner space 42, and an inlet port 43 connecting the inner space 42 and the resin passage 16 of the manifold 15 is provided on the side wall, An outlet port for connecting the inner space 42 to the gate 12 is provided on the other side, and the molten resin of the injection machine provided through the resin passage 16 is accommodated and stored by a predetermined volume.

The plunger 50 has an upper portion fixed to the upper fixing plate 61 through a plunger holder 96 . The plunger 50 is installed to be reciprocally movable between a maximum backward position forming a maximum volume and a maximum forward position forming a minimum volume within the inner space 42 of the molten resin storage cylinder 41 .

As shown in FIG. 3A, when the plunger 50 retracts to the maximum reverse position in the molten resin storage cylinder 41, the inlet port 43 of the molten resin storage cylinder 41 is opened to allow the resin passage. The molten resin of (16) is filled in the inner space (42) of the molten resin storage cylinder (41) by the maximum volume.

As shown in FIG. 3B, when the lower mold block 13 is in close contact with the bottom surface of the upper mold block 11, and the cavity 14 is closed, the plunger 50 is moved from the maximum backward position by the plunger actuator. Move to the maximum forward position.

When the plunger 50 is moved from the maximum backward position to the maximum forward position by the plunger actuator, the plunger 50 closes the inlet port 43 of the molten resin storage cylinder 41 to the resin passage of the manifold 15. Blocks the molten resin of (16) from flowing into the inner space of the molten resin storage cylinder 41, and at the same time discharges the molten resin stored in the molten resin storage cylinder 41 into the cavity 14 by a certain volume.

Here, the plunger actuator connects the upper end of the plunger 50 to the plunger holder 96, and is rotatably coupled to the upper fixing plate 61 of the mold around the hinge pin 95a, and the hinge pin 95a ) while turning by a predetermined angle around the operating lever (95) for moving the plunger 50 up and down;

a connecting rod 91 having one end connected to one side of the lower mold block 13 so as to linearly reciprocate in association with the opening and closing operation of the cavity of the lower mold block 13; and

One end is connected to the upper fixing plate 61 of the mold so as to be able to pivot around the center pin 93, one end is connected to the operation lever 95, and the other end is connected to the end of the connecting rod 91. A link bar 94 that is connected to the provided head 92 and moves the plunger 50 in the vertical direction while turning around the center pin 93 in association with the linear reciprocating motion of the connecting rod 91; characterized by being made.

3A and 3B, when the plunger 50 is raised and lowered by the plunger actuator, the valve pin 23 is moved to the gate closing position or A valve pin actuator for lifting and lowering the gate to an open position is provided.

The valve pin actuator is rotatably installed around a moving block 99 having a latch gear part on one side and a pin fixed to the upper fixed plate 61 interlocking in the same direction as the moving direction of the plunger 50 . and a pinion 98 meshed with the rack gear part of the movable block 99, and a movable block coupled to the upper end of the valve pin 23 and provided with a rack gear part on one side to mesh with the pinion 98 ( 97).

Hereinafter, the operation of the hot runner injection molding apparatus according to the second embodiment will be described with reference to FIGS. 3A and 3B.

The lower mold block 13 is separated from the upper mold block 11 by the elastic force of the spring 2 to open the cavity 14 . At this time, according to the opening operation of the lower mold block 13 , the plunger actuator moves the plunger 50 to the maximum reverse position in the molten resin storage cylinder 41 . Thereby, the inner space of the molten resin storage cylinder 41 becomes the maximum volume.

Accordingly, the molten resin extruded from the injection machine flows into the molten resin storage cylinder 41 through the resin passage 16 of the sprue 18 and the manifold 15 and is stored in a maximum volume.

In this state, as shown in FIG. 3B , when the cavity 14 is closed by moving the lower mold block 13 toward the upper mold block 11 , the connecting rod 91 according to the operation of the lower mold block 13 . ) rises in the direction of the black arrow to raise the head 92 . As the head 92 of the connecting rod 91 rises, the link bar 94 is rotated clockwise around the center pin 93 in the drawing.

By pressing the plunger holder 96 provided at the upper end of the plunger 50 while the actuating lever 95 pivots around the pin 95a according to the pivoting operation of the link bar 94, the plunger 50 is moved to the maximum. move to position At the same time, the valve pin actuator operates according to the operation of the operation lever 95 and moves the valve pin 23 to the gate opening position to open the gate.

Therefore, the plunger 50 moves from the maximum backward position to the maximum forward position, and the molten resin stored in the maximum volume in the molten resin storage cylinder 41 is transferred to the cavity 14 through the gate 12 opened by the valve pin actuator. It is discharged by a fixed amount and constant pressure.

<Third embodiment>

4A and 4B show a hot runner injection molding apparatus according to a third embodiment of the present invention.

The hot runner injection mold apparatus according to the third embodiment of the present invention includes an upper fixing plate 61 provided with a sprue 18 into which molten resin extruded from an injection machine (not shown) is installed, and a molten resin extruded from the injection machine. A manifold 15 having a resin passage 16 for dispensing, a gate 12 is provided, and the upper fixed plate 61 is spaced apart by a predetermined gap by a spring 19 from the upper fixed plate 61 When the upper mold block 11 moving close to the cavity 14 is formed with the upper mold block 11, and the upper mold block 11 is combined with the upper mold block 11 from the lower side of the upper mold block 11 and a lower mold block 13 that closes the cavity 14 and opens the cavity 14 when separated from the upper mold block 11 .

And, the upper mold block 11 is provided with a valve body (21A). The valve body 21A has an internal passage 22 to which the resin passage 16 of the manifold 15 is connected and coaxially communicates with the gate 12 of the upper mold block 11 , an open gate valve.

Hereinafter, the operation of the hot runner injection molding apparatus according to the third embodiment will be described with reference to FIGS. 4A and 4B.

The lower mold block 13 is in close contact with the upper mold block 11 to close the cavity 14 . At this time, the upper mold block 11 is spaced downward from the upper fixing plate 61 by the elastic force of the spring 19 . Accordingly, the plunger 50 coupled to the bottom surface of the upper fixed plate 61 by the plunger holder 51 is located at the maximum backward position in the inner space 42 of the molten resin storage cylinder 41, and the molten resin is stored The maximum volume is formed in the inner space 42 of the cylinder 41 .

The molten resin of the injection machine passes through the sprue 18, the resin passage 16 of the manifold 15, and the inlet port 43 of the molten resin storage cylinder 41 in order to the inner space of the molten resin storage cylinder 41 ( 42) and filled to the maximum volume.

In this state, when the upper mold block 11 and the lower mold block 13 are moved so that the upper mold block 11 is in close contact with the upper fixing plate 61 against the elastic force of the spring 19, the plunger 50 The molten resin stored in the maximum volume in the internal space 42 of the molten resin storage cylinder 41 at a constant pressure while moving from the maximum backward position to the maximum forward position of the internal space 42 of the molten resin storage cylinder 41. It is discharged into the cavity (14) through the inner passage (22A) of the valve body (21) and the gate (12).

2: Spring 3: Spring seat
11: upper mold block 12: gate
13: lower mold block 14: cavity
15: Manifold 16: Resin passage
18: sprue 18a: sprue bush
21: valve body 22: internal passage
23: valve pin 41: molten resin storage cylinder
42: interior space 43: inlet port
50: plunger 51: upper
61: upper fixing plate 62b: first flow path
62a: second flow path 71: valve cylinder
72a: upper piston chamber 72b: lower piston chamber
75: piston 81: plunger holder
95a: hinge pin 91: connecting rod
93: center pin 92: head
94: link bar 95: operating lever
96: plunger holder 97: movable block
98: pinion 99: moving block

Claims (8)

delete delete delete upper fixing plate 61;
a manifold 15 having a resin passage 16 for dispensing the molten resin extruded from the injection machine;
an upper mold block 11 having a gate 12 and spaced apart from the upper fixed plate 61 by a predetermined gap;
A cavity 14 is formed together with the upper mold block 11, and the cavity 14 is closed when combined with the upper mold block 11 from the lower side of the upper mold block 11, and the upper mold a lower mold block 13 that opens the cavity 14 when separated from the block 11;
An inner passage 22 fixed to the upper mold block 11, connected to the resin passage 16 of the manifold 15, and coaxially communicating with the gate 12 of the upper mold block 11 A valve body 21 having a;
It is provided to move between the upper limit and the lower limit along the central axis direction of the inner passage 22 in the inner passage 22 of the valve body 21, and when located at the lower limit, the lower end of the upper mold block 11 a valve pin 23 that closes the gate 12 and opens the gate 12 at its lower end when it is positioned at the upper limit position;
a valve pin actuator for operating the valve pin 23 so that the valve pin 23 moves between the upper and lower limits;
It is inserted into and fixed to the manifold 15 and has an inner space 42 coaxially connected to the inner passage 22 of the valve body 21, and the inner space 42 and the manifold are provided on side walls. Having an inlet port 43 connecting the resin passage 16 of (15), the molten resin of the injection machine provided through the resin passage 16 is accommodated and stored in the internal space 42 by a predetermined volume molten resin storage cylinder 41;
The molten resin storage cylinder (41) is installed to reciprocate between the maximum backward position forming the maximum volume and the maximum forward position forming the minimum volume in the molten resin storage cylinder (41), and when reversing to the maximum backward position ( 41) by opening the inlet port 43 to fill the molten resin in the resin passage 16 by the maximum volume of the molten resin storage cylinder 41, and when moving from the maximum backward position to the maximum forward position, the inlet port 43 ) to block the inflow of the molten resin of the resin passage 16 into the inner space 42 of the molten resin storage cylinder 41, and at the same time discharge the molten resin stored in the molten resin storage cylinder 41 by a certain volume to the plunger (50); and
In the hot runner injection molding apparatus comprising a; a plunger actuator that operates the plunger 50 to move between the maximum backward position and the maximum forward position in conjunction with the opening and closing operation of the cavity of the mold blocks (11, 13),
The plunger actuator,
The upper end of the plunger 50 is connected to the plunger holder 96, and is rotatably coupled to the upper fixing plate 61 of the mold with the hinge pin 95a as the center, and a predetermined angle around the hinge pin 95a. an operation lever 95 for moving the plunger 50 up and down while turning as much as possible;
a connecting rod 91 having one end connected to one side of the lower mold block 13 so as to linearly reciprocate in association with the opening and closing operation of the cavity of the lower mold block 13; and
One end is connected to the upper fixing plate 61 of the mold so as to be able to pivot around the center pin 93, one end is connected to the operation lever 95, and the other end is connected to the end of the connecting rod 91. A link bar 94 that is connected to the provided head 92 and moves the plunger 50 in the vertical direction while turning around the center pin 93 in association with the linear reciprocating motion of the connecting rod 91; Hot runner injection mold device for positive static pressure discharge, characterized in that made. delete 5. The method of claim 4,
The valve pin actuator interlocks in the same direction as the movement direction of the plunger 50 and is rotatably installed around a moving block 99 having a latch gear part on one side and a pin fixed to the upper fixed plate 61 . and a pinion 98 meshed with the rack gear part of the movable block 99, and a movable block coupled to the upper end of the valve pin 23 and provided with a rack gear part on one side to mesh with the pinion 98 ( 97), a hot runner injection mold device for positive static pressure discharge. delete delete

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