KR102037356B1 - Double piston Apparatus for operating a valve pin in a valve operated hot runner injection mold - Google Patents

Abstract

The present invention relates to a double piston device of a valve-operated hot runner injection mold for opening and closing a gate of the injection mold by lifting a valve pin while operating the piston by the pressure of air. The double piston device comprises a cylinder (10) with a double piston assembly (20) installed, wherein the cylinder (10) includes a first piston chamber (12) in which a first piston (30) of the diameter (D30) is accommodated, and a second piston chamber in which a second piston (40) having the larger diameter than the first piston (30) is installed. The first piston chamber (12) and the second piston chamber (13) communicate with each other, and connecting passages (23, 24) for distributing air supplied to one piston chamber to the other piston chamber are formed inside a piston rod (21).

Description

Double piston Apparatus for operating a valve pin in a valve operated hot runner injection mold}

The present invention relates to a piston mechanism for opening and closing a valve pin in a valve-operated hot runner injection mold, and more particularly, to a double piston mechanism in which the piston mechanism is constituted by a double piston mechanism, thereby increasing the operating force during valve pin opening and closing operation.

In the valve operated hot runner injection mold, it is known to configure the piston mechanism for operating the valve pin as a double piston mechanism to increase the valve opening and closing force. It is disclosed by following patent document 1 as an example of such a double piston mechanism.

In the conventional gate valve device having a double piston mechanism, as disclosed in Patent Document 1 below, the two operation holes 212 are formed inside the cylinder housing 210, and each operation hole 212, 'piston seal Pistons 240 and 250 are moved back and forth by the pressure of the incoming air, and each of these pistons 240 and 250 is installed in each of the two separate piston chamber (operation hole 212) It is coupled to each other by the coupling portion 248 of the operation, the air flowing into the two piston chamber 212 at the same time through the air inlet hole 216 and the outlet hole 218, the upper piston chamber 212 It acts on the piston 240 of the piston piston as well as the piston 250 of the lower piston chamber 212, so that the piston operating force (ultimately the force that the single valve pin 160 seals the gate) acting on the piston as a whole, the single piston Increased compared to There.

However, in the conventional double piston mechanism, the lower piston 250 has the same cross-sectional area as the upper piston 240, the coupling portion 248 penetrates in the direction of the center axis, the area where the force of air acts As the cross-sectional area of the coupling portion 248 is reduced, the area of action of air is reduced by the reduced cross-sectional area, thereby reducing the force of air acting on the lower piston. Thus, despite the use of the double piston mechanism, there was a limit that the piston actuation force could not be increased as much as the double piston.

In addition, in the conventional double piston mechanism, air inlet and outlet holes 218a and 218b (air supply passage and discharge passage) for supplying and discharging air to the upper and lower piston chambers 212 are formed in the cylinder housing 210. In addition, since the air-filled nipple (not shown) coupled to the front ends of the air inlet and outlet holes 218a and 218b protrudes, it is difficult to apply when the space in which the piston mechanism is installed is narrow.

KR 10-1677234 B1

Accordingly, the present invention improves the above-mentioned problems of the prior art, and can increase the operating force of the valve without increasing the overall size of the piston cylinder, and installs there and drills an installation hole in the mold mounting plate, It is an object of the present invention to provide a double piston mechanism for valve pin operation of a valve-operated hot runner injection mold that can be applied without limitation to an installation location, such as when it is installed in an opening formed by opening a part of an installation plate of a mold.

In the present invention for achieving the above object, in the valve-operated hot runner injection mold double piston mechanism for opening and closing the gate of the injection mold by lifting the valve pin while operating the piston by the pressure of air,

The double piston mechanism,

A cylinder having a first piston chamber and a second piston chamber disposed coaxially with the first piston chamber and partitioned from the first piston chamber by a partition wall;

A first piston is provided in the first piston chamber so as to be capable of piston movement, and the first piston divides the first piston chamber into an upper space and a lower space, and the second piston chamber is provided so as to be capable of piston movement. A second piston divided into a lower space, the first piston is coupled to one end of the first piston chamber through the partition wall, and the second piston is coupled to an outer circumference of the portion located in the second piston chamber; A double piston assembly having a piston rod coupled to a valve pin at a lower end thereof in a central axis direction;

A first air passage communicating the upper space of the first piston chamber with the first port to supply air into the upper space of the first piston chamber or to discharge the air of the upper space of the first piston chamber to the outside;

A second air cylinder configured to communicate the lower space of the second piston chamber with the second port to supply air into the lower space of the second piston chamber or to guide the air of the lower space of the second piston chamber to be discharged to the outside; in;

At least one upper connecting passage communicating the upper space of the first piston chamber and the upper space of the second piston chamber with each other to distribute air supplied to one piston chamber to the other piston chamber; And

And at least one lower connecting passage communicating the lower space of the first piston chamber with the lower space of the second piston chamber to distribute air supplied to one of the piston chambers to the other piston chamber.

The second piston coupled to the outer circumference of the piston rod has a diameter that is larger than the diameter of the first piston in order to compensate for the reduction of the working area of air due to the engagement of the piston rod, and the upper and lower connection passages It is characterized in that it is formed in the longitudinal direction inside the piston rod.

In addition, the present invention, the cylinder is composed of a separate and separate parts, is inserted and fixed in the cylinder installation hole formed in the upper plate of the hot runner injection mold, and the cover is coupled to the upper end of the cylinder installation hole to form the cylinder 1, the upper end of the piston seal is airtight, and a bush is coupled to the lower end of the cylinder installation hole to seal the lower end of the second piston seal, and the upper plate has a first port communicating with the first air passage; Another feature is that the second port is provided in communication with the second air passage.

The first air passage is formed on the outer wall of the cylinder and is formed on the bottom surface of the cover so as to communicate with the upper side piece flow path forming a flow path between the inner wall of the cylinder installation hole and the first piston chamber and the upper side piece flow path. It consists of the upper entrance formed.

Another embodiment of the present invention is the cylinder is composed of a separate and independent parts, and is installed at a predetermined distance from the wall surface of the cylinder installation space in the cylinder installation space provided on the upper plate of the hot runner injection mold,

The first air passage and the second air passage are formed on sidewalls of the cylinder.

In still another embodiment of the present invention, the first piston chamber, the second piston chamber and the partition wall are directly formed on the upper plate of the hot runner injection mold, and a part of the upper plate serves as a cylinder.

It is coupled to the cover on the top of the first piston chamber formed in the upper plate to seal the first piston chamber, the bush is coupled to the bottom of the first piston chamber to seal the second sipistone,

A first port communicating with the first air passage and a second port communicating with the second air passage are formed in the upper plate.

According to the present invention described above, the piston mechanism for operating the gate valve is composed of a double piston, but by increasing the diameter of the second piston to reduce the hydraulic pressure surface by the piston rod, it is possible to increase the force acting on the piston By increasing the operating force of the gate valve, it can withstand a large injection pressure.

In addition, by forming a connecting passage in the piston rod that simultaneously distributes the first piston chamber and the second piston chamber along the air supplied from the outside, a large operating force can be obtained with a compact structure, and the piston mechanism is not freely installed. It can be installed in one place without difficulty.

Figure 1a is a cross-sectional view of the double piston mechanism of the hot runner injection mold according to the first embodiment of the present invention, cut in the 'X-X' line direction of Figure 7, the lower connecting passages of each lower space of the two piston chamber Is a diagram showing a state of connecting.
Figure 1b is a cross-sectional view of the double piston mechanism of the hot runner injection mold according to the first embodiment of the present invention, cut along the 'Y-Y' direction of Figure 7, the upper connecting passage of each upper space of the two piston chamber Is a diagram showing a state of connecting the
2 is a view showing an operating state in which the double piston mechanism according to the first embodiment of the present invention opens the gate by retracting the valve pin from the gate with reference to FIG. 1A.
3 is a view showing an operating state in which the double piston mechanism of the first embodiment closes the gate by moving the valve pin forward to the gate, with reference to FIG. 1B.
4 is a cross-sectional view of an installation of a double piston mechanism according to a second embodiment of the present invention.
5 is a view showing a state in which the double piston mechanism according to the third embodiment of the present invention opens the gate by retracting the valve pin from the gate.
6 is a view showing a state in which the double piston mechanism according to the third embodiment of the present invention closes the gate by moving the valve pin forward to the gate.
Figure 7 is a view showing a separate double piston assembly in the double piston mechanism according to the present invention.

Hereinafter, preferred embodiments of the double piston of the hot runner injection mold according to the present invention will be described in detail according to the accompanying drawings.

In the present specification, 'up', 'down', 'left', and 'right', which are used to indicate a direction or a position, are defined based on the states shown in the drawings for the convenience of description, and the rights of the present invention. It is not intended to limit this.

1a, 1b to 3 are diagrams of a first embodiment of the present invention.

As shown in FIGS. 1A and 1B, reference numeral 1 denotes an upper plate 1 in a hot runner injection mold, and reference numeral 2 denotes a cylinder installation hole 2 formed by machining the upper plate 1. ). And reference numeral '8' refers to the manifold of the hot runner injection mold. In the first embodiment, the cylinder 10 of the double piston mechanism is composed of separate and independent parts, is tightly inserted into the cylinder mounting hole 2, and is supported on the manifold 8 of the hot runner injection mold.

The cylinder 10 has a first piston chamber 12 having a small diameter corresponding to the outer diameter D30 of the first piston 30 and a relatively corresponding outer diameter D40 of the second piston 40. It has a large diameter and is provided coaxially to the 1st piston chamber 12, and has the 2nd piston chamber 13 partitioned from the 1st piston chamber 12 by the partition 14.

The cover 5 is coupled to the upper end of the cylinder mounting hole 2 to seal the upper side of the first piston chamber 12, and the bush 6 is coupled to the lower end of the cylinder mounting hole 2.

A first port 3 for supplying external air into the first piston chamber 12 or guiding the air discharged from the first piston chamber 12 to the outside, and an external air into the second piston chamber 13 A second port 4 is formed in the upper plate 1 for supplying air or for guiding the air discharged from the second piston chamber 13 to the outside.

The first piston 30 is provided with a first piston 30 having a diameter D30, and the first piston 30 has the first piston chamber 12 as the upper space 12a and the lower space 12b. To partition.

The second piston chamber 13 is provided with a second piston 40 having a diameter D40 relatively larger than the diameter D30 of the first piston, and the second piston 40 has a second piston chamber 13. Is divided into an upper space 13a and a lower space 13b.

The piston rod 21 penetrates the partition 14 and is coupled to one end of the first piston chamber 12 at the outer circumference of the portion located at the second piston chamber 14. The second piston 40 is coupled, and the lower end is slidably coupled in the bush 6 coupled to the lower end of the piston mounting hole 2.

The piston rod 21 is fitted by inserting the valve pin 50 along the direction of the center axis at the bottom. The valve pin 50 is coupled to the piston rod 21 by being coupled to the lower coupling groove of the valve pin holder 26 coupled to the upper end of the piston rod 21.

As described above, the piston rod 21 coaxially connects the first piston 30 and the second piston 40 to configure the double piston assembly 20.

The second piston 40 has a diameter D40 that is relatively larger than the diameter D30 of the first piston 30. As the piston rod 21 penetrates and engages in the direction of the center axis of the second piston 40, the hydraulic pressure surface (air working area) of the second piston 40 decreases by the cross-sectional area of the piston rod 21. In consideration of this, the diameter of the second piston D40 is increased to increase the air working area of the second piston D40 by an area corresponding to the cross-sectional area of the piston rod 21. Therefore, the present invention can increase the piston action force by such a double piston structure.

On the other hand, the upper space 12a of the first port 3 and the first piston chamber 12 is communicated by the first air passage. In the present embodiment, the first air passage is formed in the longitudinal direction on the plurality of first air entrances 5a formed in the radial direction on the bottom surface of the cover 5 and on the outer side walls of the upper end of the cylinder 10, one end of which It is connected to the first port (3), the other end is composed of the upper side piece flow passage (15) connected to the first air entrance (5a).

The lower space 13b of the second port 4 and the second piston chamber 13 communicate with each other by the second air passage. Here, the second air passage is formed in the longitudinal direction at the second air entrance 17 provided at the lower end of the side wall of the second cylinder chamber 13b and the lower outer wall of the cylinder 10, so that the second air entrance 17 And a lower side piece flow passage 16 for communicating the second air inlet and outlet 17.

The present invention is characterized in that in the double piston structure, a connecting passage for communicating the first piston chamber 12 and the second piston chamber 13 with each other is formed as an inner passage by drilling a hole in the piston rod 21.

As shown in FIGS. 1A and 7, the connection passage connecting the lower space 12b of the first piston chamber 12 and the lower space 13b of the second piston chamber 13 to each other ( 23 and the upper connecting passage connecting the upper space 12a of the first piston chamber 12 and the upper space 13a of the second piston chamber 13 to each other (as shown in FIGS. 1B and 7). 24).

As shown in FIG. 2, when the dual piston mechanism operates to reverse the valve pin 50 to open the gate, the lower connection passage 23 is connected to the second port 4 and the lower side flow passage 16. ) And the air supplied into the lower space 13b of the second piston chamber 13 through the second air entrance 17 at the same time into the lower space 12b of the first piston chamber 12 to simultaneously discharge the second port ( The air supplied through 4) acts on the second piston 40 and the first piston 30 simultaneously to increase the piston action force.

In addition, by increasing the diameter of the second piston 40 to compensate for the reduction in the hydraulic pressure surface surface due to the coupling of the piston rod 21 it is possible to increase the force of the air acting on the piston.

Similarly, as shown in FIG. 3, when the double piston mechanism operates to advance the valve pin 50 to close the gate, the upper connecting passage 24 is the first port 3-the upper side flow path. 15. The air supplied into the upper space 12a of the first piston chamber 12 along the path of the first air entrance 5a is distributed into the upper space 13a of the second piston chamber 13, The air supplied through the first port 3 acts on the first piston 30 and the second piston 40 simultaneously, thereby increasing the piston action force.

Also in this case, the diameter of the second piston 40 is increased to compensate for the reduction in the hydraulic pressure surface due to the engagement of the piston rod 21, thereby increasing the force of air acting on the piston.

4 shows a double piston mechanism according to a second embodiment of the present invention.

As shown in Fig. 4, the second embodiment, unlike the first embodiment, does not constitute the cylinder 10 as a separate part, but directly the piston chambers 12 and 13 directly to the upper plate 1 of the injection mold. ), And the rest of the configuration and operation are the same as in the first embodiment. Detailed descriptions of the configuration and operation of the second embodiment will be omitted here.

5 and 6 show a double piston mechanism according to a third embodiment of the present invention.

5 and 6, as in the first embodiment, the cylinder 10 is configured as a separate part, but the installation space provided in the upper plate 1 of the hot runner injection mold ( 2a) is similar to the first embodiment, but the installation space 2a and the cylinder 10 are different from the first embodiment in that there is a gap, and there is no difference in other configurations. Detailed descriptions of the configuration and operation of the third embodiment will be omitted here.

As can be seen in the first to third embodiments, the double piston mechanism of the present invention can be installed in various ways in the upper plate 1, there is an advantage that can be applied without limitation.

1: upper plate
2: mounting hole
2a: installation space
3: port 1
4: second port
5: cover
5a: 1st air entrance
6: bush
8: Manifold
10: cylinder
12: First piston room
13: 2nd piston room
14: bulkhead
15: upper side flow path
16: lower side flow path
17: 2nd Air Exit
20: double piston assembly
21: piston rod
23: Lower connecting passage
24: upper connecting passage
30: first piston
40: second piston
50: valve pin

Claims (5)

In the dual piston mechanism of the valve-operated hot runner injection mold, which opens and closes the gate of the injection mold by lifting the valve pin while operating the piston by air pressure,
The double piston mechanism,
A cylinder having a first piston chamber 12 and a second piston chamber 13 disposed coaxially with the first piston chamber 12 and partitioned from the first piston chamber 12 by a partition wall 14. 10;
The first piston 30 is provided in the first piston chamber 12 so as to be capable of piston movement, and divides the first piston chamber 12 into an upper space 12a and a lower space 12b, and the second piston chamber. The second piston 40 is provided to the piston 13 so as to be able to move the piston and divides the second piston chamber 13 into the upper space 13a and the lower space 13b, and penetrates the partition wall 14 to the first. The first piston 30 is coupled to one end of the piston chamber 12, and the second piston 40 is coupled to the outer circumference of the portion located in the second piston chamber 14, and the center axial direction at the lower end thereof. A double piston assembly 20 having a piston rod 21 fitted with a valve pin 50 coupled thereto;
The upper space 12a of the first piston chamber 12 and the first port 3 communicate with each other to supply air into the upper space 12a of the first piston chamber 12 or A first air passage for discharging air in the upper space 12a to the outside;
The lower space 13b of the second piston chamber 13 and the second port 4 communicate with each other to supply air into the lower space 13b of the second piston chamber 13 or the second piston chamber. A second air passage for guiding the air in the lower space 13b of 13 to be discharged to the outside;
At least one of the upper space 12a of the first piston chamber 12 and the upper space 13a of the second piston chamber 13 communicate with each other to distribute air supplied to one piston chamber to the other piston chamber. Upper connecting passage 24; And
At least one of the lower space 12b of the first piston chamber 12 and the lower space 13b of the second piston chamber 13 communicate with each other to distribute air supplied to one piston chamber to the other piston chamber. Including the lower connecting passageway 23;
The second piston 40 coupled to the outer circumference of the piston rod 21 is larger than the diameter D30 of the first piston in order to compensate for the reduction of the working area of air due to the engagement of the piston rod 21. With increased diameter D40,
The upper and lower connection passages (24, 23) of the valve-actuated hot runner injection mold double piston mechanism, characterized in that formed in the longitudinal direction inside the piston rod (21). The method of claim 1,
The cylinder 10 is composed of separate independent parts, is inserted and fixed in the cylinder installation hole (2) formed in the upper plate (1) of the hot runner injection mold,
A cover 5 is coupled to the upper end of the cylinder installation hole 2 to seal the upper end of the first piston chamber 12 of the cylinder 10, and a bush 6 is provided at the lower end of the cylinder installation hole 2. Coupled to hermetically seal the lower end of the second piston chamber 13,
The upper plate 1 is provided with a first port 3 communicating with the first air passage and a second port 4 communicating with the second air passage. Double piston mechanism of injection mold. The method of claim 2,
The first air passage includes an upper side piece passage 15 formed on an outer wall of the cylinder 10 to form a flow path between an inner wall of the cylinder installation hole 2, the upper space 12a, and the A valve-operated hot runner injection mold double piston mechanism, comprising: a first air inlet (5a) formed at the bottom of the cover (5) to communicate with the upper side piece flow passage (15). The method of claim 1,
The cylinder 10 is composed of separate independent parts, and is installed at a predetermined distance from the wall surface of the cylinder installation space in the cylinder installation space 2a provided in the upper plate 1 of the hot runner injection mold,
Valve-actuated hot runner injection mold double piston mechanism, characterized in that the first air passage and the second air passage is formed on the side wall of the cylinder (10). The method of claim 1,
The first piston chamber 12, the second piston chamber 13 and the partition wall 14 are formed directly on the upper plate 1 of the hot runner injection mold, so that a part of the upper plate 1 Act as a cylinder,
It is coupled to the cover 5 at the upper end of the first piston chamber 12 formed in the upper plate 1 to seal the first piston chamber 12, the bush 6 at the lower end of the first piston chamber 12 ) Is combined to hermetically seal the second piston 13,
The first port (3) communicating with the first air passage and the second port (4) communicating with the second air passage are formed in the upper plate (1) of the valve operated hot runner injection mold Double piston mechanism.

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