KR20090078710A - Sensing apparatus for leakage of melted plastics into hot runner - Google Patents

Abstract

A molten resin leak check apparatus for a hot runner system is provided to prevent waste of a product material by blocking leakage of resin continually by detecting a state of the resin with a limit switch. A molten resin leak check apparatus for a hot runner system includes an inlet hole(10), a manifold(27), a nozzle(28), and a cylinder(20). The molten resin is injected through the nozzle. The manifold supplies the molten resin injected through the inlet hole to various locations. The nozzle is connected to the manifold. The cylinder opens and closes the nozzle.

Description

Sensing apparatus for leakage of melted plastics into hot runner}

The present invention relates to a molten resin leak detection device for a hot runner system, and more particularly, a molten resin leak detection for a hot runner system to detect and remove the molten resin accumulated in the hot runner in advance by using a limit switch. Relates to a device.

Generally, a hot runner system refers to a device for injecting molten resin into a mold at a high pressure while maintaining the temperature of the resin at a high temperature.

The hot runner system has been continuously researched and developed to reduce the waste of plastics in the manufacture of plastic injection molding. As shown in FIG. From the clamping plate 23, the space plate 24, the holding plate 25 and the cavity plate 26 is installed inside.

The hot runner system 10 divides the injection hole 10 for injecting into the hot runner through the nozzle (not shown) of the injection machine that stores the molten resin, and the molten resin injected through the injection hole 10 into various positions. It consists of the manifold 27 for supplying, the nozzle 28 connected to the manifold 27, and the cylinder 20 which opens and closes the nozzle 28. As shown in FIG.

The injection hole 10 is installed in the clamping plate 23, the contact area 11 is in direct contact with the injection nozzle, and the injection area having a constant angle toward the resin moving passage 29 toward the contact portion 11. The resin injection passage 12 is formed widely.

The resin injection passage 12 is a passage for smoothly supplying the molten resin injected from the nozzle of the injection machine into the resin transfer passage 29, and is perpendicular to the resin transfer passage 29, for example, 300 ° C. to 310 degrees. ℃, 800 bar high temperature and high pressure molten resin is supplied to the resin injection passage 12 of atmospheric pressure at a high speed to reach the resin movement passage (29).

The manifold 27 is installed inside the space plate 24 and keeps the resin supplied through the injection machine at a high temperature through a heater (not shown).

In the manifold 27, a plurality of resin movement passages 29, such as a lattice shape, are formed, and a plurality of resin injection holes communicating with the resin movement passage 29 are formed.

The resin injection hole may be determined differently in size and position according to the volume and injection conditions of the injection mold.

In such a resin injection hole, a nozzle 28 for injecting the supplied resin into the injection mold is fixedly installed.

The nozzle 28 not only keeps the resin passing through the manifold 27 solidified but also serves as a passage for discharging the resin into the injection mold.

When the resin is discharged through the nozzle 28, the tip of the nozzle 28 is fixed to the mold surface, and the amount of resin discharged is controlled by the lifting and lowering action of the piston provided inside the cylinder 20.

At this time, the lifting and lowering of the piston is formed by the air lines 21 and 22 in the cylinder 20, it is possible through the supplied pneumatic, and to adjust the amount of resin discharged from the nozzle 28 in accordance with the moving distance to the lifting do.

Meanwhile, the flat plate stacked as described above is fastened by fastening means such as bolts, and a plurality of spacers 13 and 14 are installed between the flat plate, and the spacers 13 and 14 are formed of the plate. It maintains the gap and serves to block the heat of the manifold 27 which is kept at a high temperature from being transferred to another plate.

In particular, the flat plate is installed in a vertical position on the ground, and the clamping plate 23 and the manifold 27 in the horizontal direction in the upper and lower portions opposite the contact portion 11 of the inlet 10 so as to maintain a constant distance The injection guide spacer 13 is provided in parallel.

However, when the molten resin supplied from the injection nozzle is injected into the resin movement passage 29 through the resin injection passage 12, the molten resin 19 of high temperature and high pressure leaks through the gap of the spacer 13 for injection guide. And accumulates in the space between the spacers 13 and 14.

Such a phenomenon in which the resin 19 accumulates in the space between the leaks and the spacers 13 and 14 primarily causes loss of product raw materials due to waste of the resin 19 and secondly, the spacers 13 and 14. ) The resin 19 is deteriorated inside while continuously accumulating in the space.

In addition, a phenomenon in which the deteriorated resin 19 is flowed back to the resin injection passage 12 in a state where the deteriorated resin 19 is full in the space of the spacers 13 and 14 is mixed with the newly supplied resin and supplied into the injection mold. It causes a defect of the product, there is a problem that the deteriorated resin 19 is stuck in the passage during the resin movement to obstruct the flow.

On the other hand, conventionally there is no device for detecting the leakage of the molten resin 19 of the present invention, the resin 19 until the resin 19 accumulated between the spacers 13, 14 space as described above leaks to the outside. It is not known whether the leakage and the amount of the leak, so that the countermeasure against the leakage of the resin 19 is weak.

In particular, after disassembling all of the hot runners, that is, the plates in a state where the resin 19 is left to leak to the outside, and checking the plate and the plate, the resin moving passage 29 and the like to remove the deteriorated resin 19 Since the next assembly must be performed, the time and cost of cleaning the inside of the hot runner and the replacement of parts are increased, which increases the manufacturing cost.

The present invention has been made in view of the above, by installing a limit switch in a place where resin is likely to leak, by detecting the amount of resin leaked through this, when a certain amount of resin leaks to stop supplying the resin And, the object of the present invention is to provide a melt leak detection device for a hot runner system to remove the resin accumulated in the interior to improve the problems caused by resin leakage.

In order to achieve the above object, the present invention provides an injection hole injected by contact of an injection machine nozzle in which molten resin is stored, a manifold for dividing and supplying molten resin injected through the injection hole into various positions, and connected to the manifold. In the hot runner system comprising a nozzle that is, and a cylinder for opening and closing the nozzle,

A plate block in which a plurality of flat plate plates are stacked such that the inlet, the manifold, the nozzle, and the cylinder are installed therein; A plurality of spacers disposed between the plate and the plate among the plate blocks; And a limit switch provided in a direction interfering with the flow of the resin in the space formed between the spacers.

It is characterized in that for detecting the resin leaking through the gap of the spacer installed on the injection port side using the limit switch.

As a preferred embodiment, it characterized in that it comprises a control unit for receiving a signal for detecting a leak of the resin from the limit switch to control the injection nozzle in a closed state.

In a more preferred embodiment, the plate block is installed in a vertical position on the ground;

In particular, the spacer is installed at regular intervals in the vertical direction, characterized in that it comprises a first spacer for injection guide formed adjacent to the injection port side, and a second spacer provided at a constant interval with the first spacer.

The limit switch may include a first limit switch and a second limit switch respectively installed in a direction that hinders resin flow at regular intervals in a downward direction from the first spacer and the second spacer.

In addition, the limit switch is mounted on a bracket installed inside one of the plate blocks, the leak detection pins that directly interfere with the flow of the resin, and the leak detection pins pressed by the accumulation of the leaked resin It is characterized in that it comprises a sensing button for outputting an electrical signal by being pressed, the housing for installing the leak detection pin and the sensing button.

As described above, according to the molten resin leak detection device for a hot runner system according to the present invention, by installing a limit switch in a place where the resin is likely to leak, by detecting the leakage of the resin, prevents the resin from continuously leaking product raw material Can prevent waste.

In addition, by preventing the accumulation of unnecessary resin in the system, it is possible to prevent the deterioration of the resin to prevent the altered resin is mixed with the newly supplied resin in advance to prevent the cause of product defects in advance.

In addition, it is only necessary to remove the leaked resin in a certain amount by checking only the place where the resin is likely to leak, without having to check the entire system in order to continuously remove the leaked and accumulated resin. It is easy and cost can be saved.

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

1 is a side view showing the overall configuration of an injection molding machine (hot runner system) according to an embodiment of the present invention, Figure 2 is a front view of Figure 1 seen from the left, Figure 3 according to the present invention in Figure 2 Detailed diagram showing melt leak detection device for hot runner system.

The present invention is focused on the point to prevent the problem that occurred in the prior art by detecting and removing the amount of the resin 19 leaked into the hot runner in advance.

Hot runner system according to an embodiment of the present invention is installed in a mold consisting of a plurality of stacked plates (23, 24, 25, 26).

The mold is a metal structure for installing a hot runner system, and may be composed of a clamping plate 23, a space plate 24, a holding plate 25, and a cavity plate 26 from above. Here, the plate blocks are installed in the vertical direction on the ground.

They are stacked in separate states after a separate machining process, and accommodate the hot runner system of the present invention therein.

The hot runner system for an injection molding machine of the present invention includes an injection hole 10 for injecting resin supplied through a nozzle of the injection machine, a manifold 27 for moving resin from the injection hole 10, and the manifold 27. It is configured to include a nozzle 28 installed in connection with the manifold 27, the cylinder 20 is installed above the manifold 27 to open and close the nozzle 28 through a piston.

The inlet 10 is a part where the hot runner system first receives molten resin from the injector. The inlet 10 penetrates the clamping plate 23 of the plate block and is connected to a part of the space plate 24. The injector nozzle is directly The contact portion 11 which is in contact with each other, and the resin injection passage 12 formed in the horizontal direction in the contact portion 11 is widened.

The manifold (27) is installed in the space plate 24 of the plate block serves to move the molten resin supplied through the inlet (10) to various positions, the resin inside the manifold (27) The movement passage 29 is formed to communicate with the resin injection passage 12 in the vertical direction.

The resin flow passage 29 is processed in a lattice shape by determining the size of the diameter according to the size of the mold injected into the manifold 27, the resin inside the manifold 27 can flow out to the outside It is supposed to be.

The resin movement passage 29 is provided with a nozzle 28 so as to discharge the resin in the manifold 27.

The nozzle 28 is installed perpendicular to the manifold 27 and serves to discharge the resin flowing out through the resin movement passage 29 into the mold, and to keep the temperature of the resin constant on the outer surface of the nozzle 28. A heater (not shown) is installed, and a temperature sensor (not shown) for detecting a temperature of the resin is installed in the nozzle 28.

The length of the nozzle 28 connected to the manifold 27 is configured to extend through the holding plate 24 to the bottom of the cavity plate 26 located on the bottom of the plate block.

This is because a groove is formed at the bottom of the cavity plate 26 in the shape of a mold to be injected, and the resin is discharged between the groove and the core as the core is coupled in a state spaced apart from the groove at a predetermined interval.

After the nozzle 28 is installed on the lower side of the manifold 27, a structure for controlling or opening / closing the amount of resin discharged through the nozzle 28 is required. For this purpose, a clamping plate located at the top of the plate block ( 23 is provided with a cylinder 20.

The cylinder 20 is installed in a form buried in the clamping plate 23, and has a piston for lifting up and down inside the manifold 27 and the nozzle 28. The piston is raised and lowered through air supplied to the cylinder 20.

That is, the pistons are provided with air lines 21 and 22 at the upper and lower sides of the cylinder 20, respectively, so that the air descends when the air is supplied above the piston and rises when the air is supplied downward.

The configuration as described above is similar to the configuration of the conventional injection molding machine. However, the present invention is easy to expose the resin through the gap inside the hot runner, in particular, the injection hole 10 side because the resin is easily exposed through the gap in the spacer 13, by installing a limit switch 15 here When a certain amount of resin 19 leaks, the limit switch 15 detects this and sends a signal to the injection machine to stop the supply of the resin.

The limit switch 15 is known to those skilled in the art and may be adopted without limitation as long as the switch can operate to block the resin supply of the injection molding machine.

Here, the place where the limit switch 15 is installed is installed between the spacers 13 and 14 installed between the clamping plate 23 and the space plate 24, and the spacers 13 and 14 have a predetermined interval. It is installed vertically.

In addition, the spacers 13 and 14 are installed in the vertical direction with the injection hole 10 formed at the center of the clamping plate 23 in the middle, and in particular, the gap between the spacers 13 and 14 for the injection guide provided on the injection hole 10 side. Since the resin 19 leaks through, the limit switch 15 may be installed in the horizontal direction so that the resin flow may be disturbed in the space formed between the plate blocks by the spacers 13 and 14.

Since the resin supplied through the resin injection passage 12 tends to flow downward under the influence of gravity, the limit switch 15 is preferably installed below the upper side of the injection hole 10.

In addition, the limit switch 15 is composed of a first limit switch 15a and a second limit switch 15b, and the first limit switch 15a is located below the injection guide spacer 13 and the second limit switch. The switch 15b is installed below the spacer 13 installed in a state spaced downward from the spacer 13 for injection guide.

The first limit switch 15a is for detecting the amount of the resin 19 leaking from the gap of the spacer 13 for injection guide, and the inner limit of the clamping plate 23 to prevent the resin 19 from flowing. A " shaped bracket 18 is installed, the switch housing is bolted to the bracket 18, and the leak detection pin 16 is extended to substantially block the flow of resin 19 on the outside of the switch housing. have.

4 is a view showing in more detail the operating state of the molten resin leak detection apparatus for a hot runner system according to the present invention in FIG.

In addition, when the operation state of the limit switch 15 configured as described above is described, as the resin 19 leaks through the gap of the spacer 13 for resin guide, the leak detecting pin 16 is formed of the resin 19. When pressurized by the flow, the detection button 17 installed on the upper side of the switch housing is pressed to generate a detection signal, and the control unit receiving the detection signal controls the injection machine to control the injection nozzle 28 in a closed state. Will cut off the supply of.

At this time, the second limit switch 15b has the same configuration and function as the first limit switch 15a.

Here, the amount of resin 19 leaking into the space between the spacers 13 and 14 depends on the gap between the resin guide spacer 13 and the leak detection pin 16 of the first limit switch 15a. Therefore, the amount of leakage of the resin 19 can be estimated by adjusting the interval.

When the resin 19 leaks through the gap inside the hot runner using the limit switch 15, first, the supply of the resin sprayed through the injection nozzle is stopped and the leak of the resin 19 is released to the operator. In this case, the inlet 10 is disassembled to remove the leaked resin 19.

As such, when the limit switch 15 is used, the leakage of the resin 19 is sensed at an appropriate time to cut off the supply of the resin, thereby improving the production efficiency of the product in terms of material supply.

By minimizing leakage of the resin 19 to prevent a certain amount of the resin 19 from being deteriorated, it is possible to prevent the cause of product defects due to the leakage of the resin 19 in advance, and the resin outside the hot runner as in the prior art Since (19) does not flow out, the trouble of having to disassemble the whole system is eliminated, and only the part of a predetermined position is disassembled and the leaked resin 19 is removed, and the system maintenance and repair were made easy.

While the invention has been shown and described with respect to certain preferred embodiments thereof, the invention is not limited to these embodiments, and has been claimed by those of ordinary skill in the art to which the invention pertains. It includes all the various forms of embodiments that can be implemented without departing from the spirit.

1 is a side view showing the overall configuration of an injection molding machine (hot runner system) according to an embodiment of the present invention.

FIG. 2 is a front view of FIG. 1 viewed from the left side. FIG.

Figure 3 is a detailed view showing a molten resin leak detection apparatus for a hot runner system according to the present invention in FIG.

4 is a view showing in more detail the operating state of the molten resin leak detection apparatus for a hot runner system according to the present invention in FIG.

5 is a view for explaining the leakage of the molten resin in the injection molding machine according to the prior art.

<Description of the symbols for the main parts of the drawings>

10: injection hole 11: contact portion

12: Resin injection passage 13: Injection guide spacer

14 spacer 15 limit switch

16: leak detection pin 17: detection button

18: bracket 19: resin

20: cylinder 21,22: air line

23: clamping plate 24: space plate

25 holding plate 26 cavity plate

27: manifold 28: nozzle

29: resin transfer passage

Claims (5)

An injection hole injected through contact with the injection machine nozzle in which the molten resin is stored, a manifold for dividing and supplying the molten resin injected through the injection hole into various positions, a nozzle connected to the manifold, and a cylinder for opening and closing the nozzle In the hot runner system consisting of, A plate block in which a plurality of flat plate plates are stacked such that the inlet, the manifold, the nozzle, and the cylinder are installed therein; A plurality of spacers disposed between the plate and the plate among the plate blocks; And A limit switch provided in a direction interfering with the flow of resin in a space formed between the spacers, Melt resin leak detection device for hot runner system, characterized in that for detecting the resin leaking through the gap of the spacer installed on the injection port side using the limit switch. The method according to claim 1, Receiving a signal for detecting the leakage of the resin from the limit switch, the molten resin leak detection device for a hot runner system, characterized in that it comprises a control unit for controlling the injection nozzle. The method according to claim 1 or 2, The plate block is installed in a vertical position on the ground; The spacer is installed at regular intervals in the vertical direction, the hot runner system characterized in that it comprises a first spacer for injection guide formed adjacent to the injection port side, and a second spacer provided at regular intervals with the first spacer. Molten resin leak detector. The method according to claim 3, The limit switch may include a first limit switch and a second limit switch respectively installed in a direction interrupting the resin flow at regular intervals in the downward direction from the first spacer and the second spacer. Resin Leak Detector. The method according to claim 3, The limit switch is mounted on a bracket installed inside one of the plate blocks, and is pressed by a leak detection pin that directly interferes with the flow of resin and a leak detection pin that is pressed by the accumulation of the leaked resin. And a detection button for outputting an electrical signal to the bag, and a housing in which the leak detection pin and the detection button are installed.

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