KR102085009B1 - mold locking device of injection molding machine - Google Patents

Abstract

The present invention relates to a mold locking device of an injection molding machine that prevents the clamping of the U-shaped clamping plate and the driving cylinder from clamping in the vertical direction so that the fixed mold and the movable mold are not opened in opposite directions with respect to the opening direction.

Description

Mold locking device of injection molding machine

The present invention relates to a mold locking device of an injection molding machine that prevents the clamping of the U-shaped clamping plate and the driving cylinder from clamping in the vertical direction so that the fixed mold and the movable mold are not opened in opposite directions with respect to the opening direction.

As a mold clamping apparatus of a conventional injection molding machine, what is known in patent document 1 (Korean Patent Publication No. 10-0931804) is proposed.

As shown in FIG. 1, the mold clamping apparatus 2 of the injection molding machine of Patent Document 1 includes a stationary mold plate 10 having a first mold part 11 and a movable mold plate 20 having a second mold part 21. ), A guide bar 30 for guiding movement of the movable die 20 and providing a clamping force by hydraulic pressure acting on the die cylinder 31, and a transfer cylinder 40 for forwarding and moving the movable die 20 forward and backward. And a locking nut 50 mounted to the movable die 20 to couple the guide bar 30 to the movable die 20 to lock the movable die 20.

Here, the guide bar 30 guides the linear motion of the movable plate 20, and the guide bar 30 actuates the hydraulic pressure of the hydraulic system 32 to enter and exit the mold cylinder 31 installed in the stationary plate 10. Advance back and forth by.

In the conventional locking device for locking the movable plate 20 through the lock nut 50, the lock nut 50 is fixed to the movable plate 20, as shown in detail in FIG. 2. Is installed inside. The lock nut 50 is moved forward / backward in the radial direction of the guide bar 30 by the nut cylinder 70, and the teeth 35 formed in the guide bar 30 and the teeth 55 formed in the lock nut 50. Is tightened / unlocked by

Such a mold clamping device joins or molds the first and second mold parts 11 and 21 provided in the stationary mold plate 10 and the movable mold plate 20. All of them are made by moving the movable die 20 back and forth by the transfer cylinder 40. After molding, as shown in FIG. 2, the nut cylinder 70 is operated to move the lock nut 50 to advance the lock nut ( Engage the teeth 55 of the guide bar 30 with the teeth 55 of the guide bar 30. The teeth 35 of the guide bar 30 and the teeth 55 of the lock nut 50 are vertical surfaces 35a and 55a. It has inclined surfaces 35b and 55b, and after fastening, the load Fc can be transmitted only in one direction of the vertical surfaces 35a and 55a.

When the lock nut 50 and the guide bar 30 are fastened as described above, the mold cylinder 31 receives the high pressure hydraulic oil to pull the guide bar 30, and accordingly the teeth 35 of the guide bar 30. The vertical surface 35a of the puller pulls the vertical surface 55a of the teeth 55 of the lock nut 50, and the first and second mold portions 11 and 21 are strongly joined by this force, and the high-pressure molten resin is introduced into the mold. It will not open when is injected. When the molten resin is injected into the mold and the molded article is molded, the first mold part 11 and the second mold part 21 are joined by the molded article. Therefore, in order to open the mold, a load equal to or greater than this joining force must be applied. Is called a high pressure dog.

However, since the locking nut 50 and the guide bar 30 are tooth-engaged to form a fine but gap, the guide nut 30 may be slightly pushed while the lock nut 50 is pushed by the pressure during injection molding. have.

This is because the guide bar 30 is subjected to the clamping force by the mold cylinder 31, so that the hydraulic pressure is compressed, the guide bar 30 is also moved so much that the mold is finely opened.

Such minute openings have problems such as quality problems such as burrs, increased aging of the mold / injector, and increased power consumption due to high clamp force.

On the other hand, Patent Document 2 (Japanese Patent Application Laid-Open No. 50-10869), in order to prevent such a rolling, in the injection molding machine shown in Figs. The chuck plate 5 is used.

Since the chuck plate 5 maintains the mold closing of the mold 9, the chuck plate 5 holds a fine opening during injection.

However, as shown in FIG. 5, the taper surface b is formed in the end surface of the chuck plate 5, and when the metal mold 9 is about to open | release, there is a very big possibility that fine movement may occur.

In addition, since it is the driving cylinder 10 that pushes the mold 9 toward the injection apparatus 8, the driving cylinder 10 is pushed backward while the mold 9 is pushed back by the pressure at the time of injection through the nozzle 6. There is a big risk of being pushed.

That is, the driving cylinder 10 is provided with a forward circuit and a reverse circuit, respectively, and when hydraulic pressure is supplied to the forward circuit, the reverse circuit discharges the hydraulic pressure. When the external force is applied to the cylinder even when the cylinder is not operated, the hydraulic pressure is compressed. It's fine.

When the mold mold is opened finely by the injection pressure due to such a fine rolling phenomenon, the quality problems such as burrs, the aging of the mold and the injection molding machine, and the increase in power consumption due to the high clamp force change occur.

Patent Document 1: Korean Patent Publication No. 10-0931804 Patent Document 2: Japanese Utility Model Publication No. 50-10869

The present invention has been made in order to solve the above-mentioned problems, the injection molding machine of the mold locking device of the injection molding machine which significantly improves the work cost by improving the finishing work of the operator by injection molding with a clamping force that completely blocked the mold micro-opening by the injection pressure It aims to provide.

In order to achieve the above object, the mold locking device of the injection molding machine according to claim 1 of the present invention, a fixed mold having an injection gate; A movable mold for forming a mold cavity at the fixed mold and the mold closing; And a clamping member for clamping the fixed mold and the movable mold, wherein the clamping member includes a clamping groove formed on an outer surface in a direction perpendicular to an opening direction of the fixed mold and the movable mold, and the clamping member. And a U-shaped clamping plate inserted into the groove, an actuator for moving the clamping plate forward and backward with respect to the clamping groove, wherein the clamping plate connects the vertical plate to the vertical plate inserted into the clamping groove. It comprises a horizontal plate and a rotating roller installed on the inner surface of the vertical plate.

In the mold locking apparatus of the injection molding machine according to claim 2 of the present invention, the actuator includes a piston and a cylinder connected to the horizontal plate, a first and a second hydraulic line connected to the first and second chambers of the cylinder, First and second pilot operated check valves installed in the first and second hydraulic lines.

According to the present invention has the following effects.

Since the rotating roller of the vertical plate is inserted into the clamping groove formed at right angles to the mold opening (opening) direction, the C-shaped clamping plate is tightly pressed for opening, thereby preventing mold opening due to insufficient clamping force.

In other words, the rotary rollers reduce friction as much as possible in contact with the clamping groove while facilitating the forward and backward movement of the clamping plate, while providing a perfect clamping force without slipping by sliding tightly at right angles to the opening direction.

In addition, since the first and second pilot operated check valves are installed in the forward and backward hydraulic lines connected to the forward and backward chambers of the cylinder, they do not move unless the hydraulic pressure for operating the drive cylinder is operated. The rolling back of the clamping plate does not occur completely, producing a good injection product.

1 is a schematic view showing a clamping apparatus of a conventional injection molding machine.
FIG. 2 is an enlarged view illustrating main parts showing a state in which the lock nut of the clamping device shown in FIG. 1 is locked and a clamping force is applied to the guide bar. FIG.
3 is an enlarged view illustrating main parts illustrating a state in which the guide bar is pushed in a mold opening direction in FIG. 2;
4 and 5 is a cross-sectional plan view during mold closing and mold opening as another conventional injection molding machine.
6 and 7 is a schematic view showing a mold locking device of an injection molding machine according to a preferred embodiment of the present invention, the mold mold closing state and the mold mold opening state.
8 and 9 show the U-shaped clamping plate inserted (locked) or not inserted (unlocked) in the clamping groove.
10 is a circuit diagram of a pilot operation check valve using the present invention.
11 and 12 are explanatory views of the forward and backward operation of the pilot operation check valve of FIG. 10.

Hereinafter, with reference to the accompanying drawings will be described a preferred embodiment of the present invention, but the same reference numerals for the same parts as in the prior art and detailed description thereof will be omitted.

6 and 7 are schematic views showing a mold locking device of an injection molding machine according to a preferred embodiment of the present invention, which is a state diagram at the time of mold closing and mold opening, and FIGS. 8 and 9 are C-shaped clamping plates in a clamping groove. Fig. 10 is a circuit diagram of a pilot operation check valve using the present invention, and Figs. 11 and 12 are pilot operation check valve operating structures in Figs. 6 and 7 states.

6 and 7, the mold locking device 100 of the injection molding machine according to the embodiment of the present invention has a fixed mold 110 having an injection gate 111, and a mold 100 and a mold closing time. A movable mold 130 for forming the mold cavity 120, and a clamping member 150 for clamping the fixed mold 110 and the movable mold 130.

The stationary mold 110 is fixed to an injection machine (not shown) for injection into the injection gate 111.

The movable mold 130 is opened by mold approaching or retiring by approaching the fixed mold 110 in a straight direction.

Due to the horizontal arrangement of the stationary mold 110 and the movable mold 130, the movable mold 130 may be pushed in a direction to be retired by the injection pressure.

The clamping member 150 for preventing this is a U-shaped clamping groove 160 formed on the upper and lower surfaces of the fixed mold 110 and the movable mold 130, and the U-shaped inserted into the clamping groove 160. It includes a clamping plate 170 of the, and the actuator 180 for advancing the clamping plate 170 with respect to the clamping groove 160.

The clamping groove 160 is formed in a direction perpendicular to the axial direction when the opening or closing direction of the molds 110 and 130 is called an axial direction, and is perpendicular to the opening direction of the movable mold 130. Will be deployed.

The U-shaped clamping plate 170 is installed on a vertical plate 171 inserted into the clamping groove 160, a horizontal plate 173 connecting the vertical plate 171, and an inner surface of the vertical plate 171. Rotating roller 175 to be included.

That is, the thickness of the vertical plate 171 is smaller than the width of the clamping groove 160, and is advanced back and forth in a parallel state in which the inner surface of the vertical plate 171 and the inner surface of the clamping groove 160 face each other. . At this time, since the rotary roller 175 enters or exits the inner surface of the clamping groove 160, the clamping plate ( 170) is pushed back slightly to solve the lack of clamping force.

As shown in FIGS. 8 to 10, the actuator 180 includes a piston 181 connected to the horizontal plate 173, a driving cylinder including a cylinder 183, and a first chamber 185 of the cylinder 183. First and second pilot operated check valves installed in the first and second hydraulic lines 182 and 184 connected to the second chamber 186 and the first and second hydraulic lines 182 and 184. Valve) C1 (C2).

The pilot operated check valve opens the check valve so that the hydraulic pressure on the opposite side can be released only when the hydraulic pressure to operate the cylinder occurs (see US Patent No. 6,871,574 for details).

That is, in order to lock the mold opening by moving the piston 181 forward as shown in FIG. 11, oil is introduced into the second chamber 186 through the second pilot operation check valve C2.

At this time, the pressure of the oil flowing through the second hydraulic line 184 is provided along a passage connected to the first pilot operation check valve C1 (single dashed line) to open the first pilot operation check valve C1 to open the first pilot operation check valve C1. Oil in the first chamber 185 is discharged through the first hydraulic line 182.

When the forward movement of the piston 181 stops and the flow pressure of the oil disappears, the oil in the first and second chambers 185 and 186 is prevented from flowing back by the first and second pilot operation check valves C1 and C2, Pushing of the piston 181 is completely prevented.

On the contrary, as shown in FIG. 12, in order for the piston 181 to reverse and unlock the oil, the oil flows into the first chamber 185 through the first pilot operation check valve C1 through the first hydraulic line 182.

At this time, the pressure of the oil flowing through the first hydraulic line 182 is provided along a passage connected to the second pilot operation check valve C2 (single dashed line) to open the second pilot operation check valve C2 to open the second pilot operation check valve C2. The oil in the second chamber 186 is drained through the second hydraulic line 184.

When the backward movement of the piston 181 stops and the flow pressure of the oil disappears, the oil in the first and second chambers 185 and 186 is prevented from flowing back by the first and second pilot operation check valves C1 and C2.

The actuator 180 is supported by the bracket (B) to the stationary mold (110).

According to the present embodiment as described above, not only the clamping resisting perpendicularly to the opening direction of the mold by using the rotary roller but also a pilot operation check valve is applied, thereby maintaining mold closing force without any micro-opening between the molds. Because of the injection molding in the state of making it, it greatly contributes to the reduction of the aging of the mold and the injection machine, the reduction of the electric charge and the stabilization of the injection quality.

The embodiments according to the inventive concept may be variously modified and have various forms, so the embodiments are illustrated in the drawings and described in detail herein. It is not intended to be limited to these, but includes all modifications, equivalents, or substitutes included in the spirit and scope of the present invention.

100: mold locking device of injection molding machine
110: fixed mold 111: injection gate
120: mold cavity 130: movable mold
150: clamping member 160: clamping groove
170: U-shaped clamping plate 171: vertical plate
173: horizontal plate 175: rotating roller
180: actuator 181: piston
183 Cylinder B Bracket
C1, C2; Pilot Operated Check Valve

Claims (2)

Fixed mold 110 having an injection gate 111, movable mold 130 to form a mold cavity 120 when the mold 110 and the mold closing, clamping the fixed mold 110 and the movable mold 130 Including a clamping member 150,
The clamping member 150 is a clamping groove 160 formed on the outer surface in the direction perpendicular to the opening direction of the stationary mold 110 and the movable mold 130, and the U-shaped inserted into the clamping groove 160 A clamping plate 170 of the shape and the actuator 180 for advancing the clamping plate 170 with respect to the clamping groove 160,
The U-shaped clamping plate 170 is installed on a vertical plate 171 inserted into the clamping groove 160, a horizontal plate 173 connecting the vertical plate 171, and an inner surface of the vertical plate 171. Including a rotating roller 175,
The inner surface of the vertical plate 171 is advanced back and forth in a parallel state facing each other with the inner surface of the clamping groove 160,
The actuator 180 includes a piston 181 connected to the horizontal plate 173, a cylinder 183, and first and second hydraulic lines connected to the first chamber 185 and the second chamber 186 of the cylinder 183. (182) (184) and the mold of the injection molding machine including the first and second pilot operated check valve (C1) (C2) installed in the first and second hydraulic lines (182) (184) lock.
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