JP2003205530A - Injection molding machine and nozzle therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a nozzle for an injection molding machine capable of performing alteration work of a raw material resin easily and efficiently. <P>SOLUTION: The nozzle of the injection molding machine is constituted of a nozzle body 10 and a connection block 30, and the nozzle body 10 is constituted of a casing 11 and a core 12. A first flow channel 15 is formed to the center of the core 12, and a second flow channel 16 is formed between the outer peripheral surface of the core 12 and the inner peripheral surface of the casing 11. The first and the second flow channels 15 and 16 meet with each other in front of the core 12 to be connected to the discharge port 13 provided to the leading end of the casing 11. The connection block 30 has first and second supply routes 31 and 32 formed therein. The first supply route 31 connects a sub-injection device 41 and a first port 17 and has a first three-way valve 33 provided on the way thereof. The second flow route 32 connects a main injection device 42 and a second port 18 and has a second three-way valve 34 provided on the way thereof. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nozzle for an injection molding machine, and more particularly to an injection molding nozzle suitable for sequentially switching and using a plurality of kinds of raw material resins. The present invention also relates to a molding method using such a nozzle for an injection molding machine.

[0002]

2. Description of the Related Art In a conventional injection molding machine, a lot switching operation is performed as follows when changing a raw material resin. That is, the remaining resin for the old lot is extracted from the raw material hopper, the resin in the heating barrel is discharged to empty the inside, and then the resin for the new lot is charged into the hopper. Then, the resin for the old lot remaining in the heating barrel and the injection nozzle is purged with the resin for the new lot, and then the production operation using the resin for the new lot is performed.

Such a lot switching operation causes a reduction in the actual operating time of the injection molding machine. In particular, in the current situation where the production unit is becoming smaller in lot size, the ratio of the time of the lot switching work to the total work time becomes large, which is a factor that hinders the production efficiency of the injection molding machine.

As a method for solving this, a method has been proposed in which two injection devices are provided, they are placed on a dolly, and the dolly is slid to replace the injection devices. But,
This method is not practical because it requires a large apparatus.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems when changing a raw material resin in a conventional injection molding machine, and an object of the present invention is to switch the raw material resin. An object of the present invention is to provide a nozzle for an injection molding machine that can perform work easily and efficiently, and a method of using the nozzle.

[0006]

[Means for Solving the Problems] A nozzle for an injection molding machine is
It is connected to the back surface of the mold through a discharge port provided at the tip, has a first port and a second port, and has a first flow path connecting the first port and the discharge port and a first flow path connecting the second port and the discharge port. A nozzle body having two flow passages formed therein, a first supply path for guiding the first molten resin to the first port, and a branch in the middle of the first supply path to bring the first molten resin to the outside. A first branch path for discharging, a state of being provided at a branch point of the first branch path and connecting an upstream part of the first supply path to a downstream part, and an upstream part of the first supply path being the first branch path. A first three-way valve that can be switched between a state in which the second molten resin is connected to the second port, and a second supply path that guides the second molten resin to the second port; At the branch point of the second branch path and the second branch path for releasing the molten resin to the outside And a second three-way valve switchable between a state in which the upstream portion of the second supply path is connected to the downstream portion and a state in which the upstream portion of the second supply path is connected to the second branch path, It is characterized by having.

Preferably, in the above injection molding machine nozzle, the first flow path is a hole-shaped flow path formed on a central axis of the nozzle body, and the second flow path is the first flow path. It is an annular flow passage formed around the passage, and the first flow passage and the second flow passage meet before the discharge port.

Preferably, in the above injection molding machine nozzle, the nozzle body is composed of an outer nozzle and an inner nozzle incorporated in the outer nozzle, and the discharge port is formed at a tip of the outer nozzle. The first flow path is formed on the central axis of the inner nozzle, and the second flow path is formed between the outer peripheral surface of the inner nozzle and the inner peripheral surface of the outer nozzle.

Preferably, the injection molding machine nozzle further includes a first on-off valve provided on the first branch path and a second on-off valve provided on the second branch path. .

Next, a method of using the nozzle for an injection molding machine of the present invention will be described.

When injection molding is performed using the first molten resin, the second three-way valve shuts off the middle of the second supply path, and the first three-way valve closes the upstream portion of the first supply path. The first molten resin is supplied into the nozzle body while being connected to the downstream portion. On the other hand, when injection molding is performed using the second molten resin, the first three-way valve shuts off the middle of the first supply path, and the second three-way valve upstream of the second supply path. The second molten resin is supplied into the nozzle body with the portion connected to the downstream portion.

In this way, by using the first and second three-way valves to switch between the above two states, the raw material resin used can be changed easily and in a short time. be able to.

Further, when injection molding is performed using the third raw material resin, while performing injection molding using the second molten resin, the first three-way valve is used to perform the injection molding. By connecting the upstream portion of one supply path and the first branch path, the remaining first molten resin in the path can be purged. In this way, while injection molding is being performed using one resin, the other resin can be purged on the upstream side of the first (or second) three-way valve. It is possible to shorten the non-operating time of the injection molding machine at the time of changing the above and increase its actual operating rate.

When two kinds of resin are used alternately and it is not necessary to purge the resin, another opening / closing mechanism such as a stop valve is used instead of the first and second three-way valves. Can be used.

An injection molding machine in which the above nozzle is used has a first injection unit connected to the upstream side of the first supply path and a second injection unit connected to the upstream side of the second supply path. And an injection unit.

[0016]

1 shows an example of a nozzle for an injection molding machine according to the present invention. In the figure, 10 is a nozzle body,
11 is an outer nozzle, 12 is an inner nozzle, 13 is a discharge port, 15 is a first flow path, 16 is a second flow path, 17 is a first port, 18 is a second port, 31 is a first supply path, 32
Is a second supply path, 33 is a first three-way valve, 34 is a second three-way valve, 35 is a first branch path, and 36 is a second branch path.

This injection molding nozzle comprises a nozzle body 1
0 and a connection block 30. A main injection device 42 and a sub injection device 41 are connected to the connection block 30 as described below.

The nozzle body 10 includes an outer nozzle 11
And an inner nozzle 12 incorporated therein. At the tip of the outer nozzle 11, a discharge port 1
3 is provided. The tip of the outer nozzle 11 is connected to a gate provided on the back surface of a mold (not shown). The rear end of the outer nozzle 11 is fixed to the connecting block 30.

A through hole 15 (hereinafter referred to as a first flow path) is formed in the center of the inner nozzle 12 in the axial direction. The outer peripheral surface of the inner nozzle 12 and the outer nozzle 11
An annular channel 16 (hereinafter referred to as a second channel) is formed between the inner peripheral surfaces of the. First channel 15 and second channel 16
After merging in front of the inner nozzle 12, the discharge port 1
Connected to 3.

A first port 17 for introducing the first molten resin is provided on the rear end surface of the inner nozzle 12. A second port 18 for introducing the second molten resin is provided on the rear end surface of the outer nozzle 11.
The first port 17 is connected to the discharge port 13 via the first flow path 15. The second port 18 is connected to the discharge port 13 via the second flow path 16.

Inside the connection block 30, a first supply path 31 and a second supply path 32 are formed. The first supply path 31 is connected to the auxiliary injection device 41 on the upstream side and connected to the first port 17 on the downstream side. In the middle of the first supply path 31, a rotary valve type first three-way valve 33 is provided.
Is provided. The first branch path 35 is branched from the first supply path 31 via the first three-way valve 33. A first opening / closing valve 37 is provided in the middle of the first branch path 35. The second supply path 32 is connected to the main injection device 42 on the upstream side and is connected to the second port 18 on the downstream side. A rotary valve type second three-way valve 34 is provided in the middle of the second supply path 32. Second branch route 3
6 through the second three-way valve 34, the second supply path 32
It has been branched from. A second opening / closing valve 38 is provided in the middle of the second branch path 36.

By operating the first three-way valve 33 and the second three-way valve 34, the kind of the molten resin supplied into the nozzle body 10 can be changed between the first molten resin and the second molten resin. You can switch with.

FIG. 2 shows a sectional view of the first three-way valve 33 and its surroundings. The first three-way valve 33 has the first supply path 31.
2 (a), the state where the upstream portion 31a and the downstream portion 31b of the first supply path are connected to each other, and the upstream side of the first supply path as shown in FIG. 2 (b). Between the state in which the upstream portion 31a is connected to the first branch path 35 at the same time when the connection between the portion 31a and the downstream portion 31b is cut off,
It is configured to be switchable. Furthermore,
An opening / closing valve 37 is provided in the middle of the first branch passage 35. The second three-way valve 34, the upstream portion 32a and the downstream portion 32b of the second supply passage, the second branch passage 36, and the opening / closing valve 38 are also similarly configured.

When injection molding is performed using the first molten resin, the second three-way valve 34 shuts off the middle of the second supply path (FIG. 2 (b)) and the first three-way valve 33 is used. Then, the upstream portion 31a and the downstream portion 31b of the first supply path are connected (FIG. 2 (a)). Similarly, when injection molding is performed using the second molten resin, the first three-way valve 33 shuts off the middle of the first supply path (FIG. 2B), and the second three-way valve 34 is used. And the upstream portion 32a and the downstream portion 32b of the second supply path
Are connected (FIG. 2 (a)).

When changing the raw material resin with the above injection molding machine nozzle (FIG. 1), only the resin of the old lot remaining downstream from the confluence of the first flow path 15 and the second flow path 16 is replaced with new one. If the resin in the lot is replaced, the injection molding using the resin in the new lot can be started.

When injection molding is performed using the third raw material resin, the first supply is performed via the first three-way valve 33 while the injection molding is performed using the second molten resin. It is possible to connect the upstream portion 31b of the path and the first branch path 35 and open the first opening / closing valve 37 to purge the first molten resin remaining in the path. Then, in the case of performing injection molding using the fourth raw material resin, while performing injection molding using the third molten resin, the second supply path of the second supply path is provided via the second three-way valve 34. It is possible to connect the upstream portion 32b and the second branch path 36 and open the second opening / closing valve 38 to purge the second molten resin remaining in the path.

As described above, while the injection molding is performed using one resin, the other resin is purged on the upstream side of the first three-way valve 33 (or the second three-way valve 34). Since it can be performed, the non-operation time of the injection molding machine when changing the raw material resin can be shortened.

After switching to the third resin, it is necessary to replace the flow path on the downstream side of the first three-way valve 33 (or the second three-way valve 34) with the third resin. In order to reduce the waste of resin at this time, it is preferable that the volume of the flow path on the downstream side of the first three-way valve 33 (or the second three-way valve 34) is smaller.

FIG. 3 shows another example of a nozzle for an injection molding machine according to the present invention. Contrary to the previous example (FIG. 1), in this example, as shown below, the flow path (first flow path 15) at the center of the nozzle is connected to the main injection device 71, and the annular flow path around it is connected. The (second flow path 16) is connected to the auxiliary injection device 72.

This injection molding machine nozzle comprises a nozzle body 10, a first connecting block 50 and a second connecting block 60. The nozzle body 10 is composed of an outer nozzle 11 and an inner nozzle 12 incorporated therein. A discharge port 13 is provided at the tip of the outer nozzle 11. Outer nozzle 11
Is connected to a gate provided on the back surface of a mold (not shown).

At the center of the inner nozzle 12, a through hole 15 (first flow path) is formed in the axial direction. An annular flow path 16 (second flow path) is formed between the outer peripheral surface of the inner nozzle 12 and the inner peripheral surface of the outer nozzle 11. The first flow path 15 and the second flow path 16 are joined to each other in front of the inner nozzle 12 and then connected to the discharge port 13.

The rear end surface of the inner nozzle 12 is provided with a first port 17 for introducing the first molten resin. The first port 17 is connected to the discharge port 13 via the first flow path 15. On the side surface of the outer nozzle 11,
A second port 18 is provided for introducing the second molten resin. The first port 17 is connected to the discharge port 13 via the first flow path 15. The second port 18 is the second flow path 1
It is connected to the discharge port 13 via 6.

The inner nozzle 12 is connected at its rear end face to the main injection unit 71 via the first connecting block 50. A first supply path 51 is formed inside the first connection block 50. The first supply path 51 connects to the main injection device 71 on the upstream side and the first port 17 on the downstream side.
Connected to. A rotary valve type first three-way valve 53 is provided in the middle of the first supply path. The first branch path 55 is branched from the first supply path 51 via the first three-way valve 53. A first opening / closing valve 57 is provided in the middle of the first branch path 55.

Similarly, the outer nozzle 11 is connected to the auxiliary injection device 72 through the second connecting block 60 on its side surface. A second supply path 62 is formed inside the second connection block 60. The second supply path 62 is connected to the auxiliary injection device 72 on the upstream side and connected to the second port 18 on the downstream side. In the middle of the second supply path 62,
A second three-way valve 64 of the rotary valve type is provided. The second branch path 66 is branched from the second supply path 62 via the second three-way valve 64. A first opening / closing valve 68 is provided in the middle of the first branch path 66.

By operating the first three-way valve 53 and the second three-way valve 64, the kind of the molten resin supplied into the nozzle body 10 can be changed between the first molten resin and the second molten resin. You can switch with.

The example shown in FIG. 3 corresponds to the example shown previously (FIG. 1).
Compared with, the shape of the flow passage on the downstream side from the first three-way valve 53 and the second three-way valve 64 is simple, and the volume thereof is also small. Therefore, when switching to the third resin, the time required to replace the resin in the flow passage on the downstream side from the first three-way valve 53 (or the second three-way valve 64) can be shortened.

FIG. 4 shows another example of the injection molding machine nozzle according to the present invention. In this example, a modification is added to the example shown in FIG. 3 (FIG. 3), and a second three-way valve 64 provided in the middle of the second supply path 62 is arranged in the vicinity of the second port 18. With this configuration, after switching to the third resin, the time required to replace the resin in the flow passage on the downstream side from the second three-way valve 64 can be shortened.

[0038]

According to the nozzle for an injection molding machine of the present invention,
A state in which the first raw material resin is supplied into the nozzle body via the first supply path and the first three-way valve, and a second raw material resin in the nozzle body via the second supply path and the second three-way valve. It is possible to change the raw material resin used by switching between the state of supplying the raw material resin and the state of supplying the raw material resin. Therefore, according to the nozzle for an injection molding machine of the present invention, the work of changing the raw material resin in the injection molding machine can be easily performed in a short time.

Further, while the injection molding is performed using one raw material resin, the other raw material resin can be purged on the upstream side of the first (or second) three-way valve. The non-operation time of the injection molding machine when switching from the second raw material resin to the third raw material resin can be shortened.

[Brief description of drawings]

FIG. 1 is a view showing an example of a nozzle for an injection molding machine of the present invention.

FIG. 2 is a partially enlarged view of a three-way valve used in the nozzle for an injection molding machine of the present invention and a path around it, (a) and (b).
The figure showing two states of this three-way valve.

FIG. 3 is a diagram showing another example of the nozzle for an injection molding machine of the present invention.

FIG. 4 is a view showing another example of the nozzle for an injection molding machine of the present invention.

[Explanation of symbols]

10 ... Nozzle body, 11 ... Outer nozzle, 12 ... Inner nozzle, 13 ... Discharge port, 15 ... First flow path (through hole), 16 ... Second channel (annular channel), 17 ... the first port, 18 ... Second port, 20 ... Mold, 21 ... gate, 30 ... Connection block, 31, 51 ... First supply path, 32, 62 ... Second supply path, 33, 53 ... the first three-way valve, 34, 64 ... second three-way valve, 35, 55 ... First branch path, 36, 66 ... Second branch path, 37, 57 ... First opening / closing valve, 38, 68 ... Second on-off valve, 41, 72 ... Sub-injection device, 42, 71 ... Main injection device, 50 ... the first connecting block, 60 ... Second connection block.

Claims (11)

[Claims] 1. A first flow path and a second port which are connected to a back surface of a mold through a discharge port provided at a tip, have a first port and a second port, and connect the first port and the discharge port. A nozzle body in which a second flow path connecting the discharge ports is formed, a first supply path for guiding the first molten resin to the first port, and a branch in the middle of the first supply path A first branch path for discharging the molten resin to the outside, a state of being provided at a branch point of the first branch path and connecting an upstream part of the first supply path to a downstream part, and an upstream part of the first supply path. A first three-way valve that can be switched between a state in which is connected to the first branch path, a second supply path that guides the second molten resin to the second port, and a branch from the middle of the second supply path. And a second branch path for discharging the second molten resin to the outside, A second switch that is provided at a branch point of the branch route and can switch between a state in which the upstream portion of the second supply route is connected to the downstream portion and a state in which the upstream portion of the second supply route is connected to the second branch route A nozzle for an injection molding machine, which is equipped with the three-way valve of. 2. The first flow channel is a hole-shaped flow channel formed on the central axis of the nozzle body, and the second flow channel is an annular flow channel formed around the first flow channel. The nozzle for an injection molding machine according to claim 1, wherein the nozzle is a passage, and the first flow passage and the second flow passage merge in front of the discharge port. 3. The nozzle body is composed of an outer nozzle and an inner nozzle incorporated in the outer nozzle, the discharge port is formed at a tip of the outer nozzle, and the first flow path is the inner nozzle. The injection molding machine according to claim 2, wherein the injection path is formed on a central axis of a nozzle, and the second flow path is formed between an outer peripheral surface of the inner nozzle and an inner peripheral surface of the outer nozzle. Nozzle. 4. The first opening / closing valve provided on the first branch passage, and the second opening / closing valve provided on the second branch passage are further provided. The nozzle for an injection molding machine according to any one of 3 to 3. 5. A first flow path and a second port which are connected to the back surface of the mold through a discharge port provided at the tip and have a first port and a second port, and which connect the first port and the discharge port. A nozzle body in which a second flow path connecting the discharge ports is formed, a first supply path for guiding the first molten resin to the first port, and a branch in the middle of the first supply path A first branch path for discharging the molten resin to the outside, a state of being provided at a branch point of the first branch path and connecting an upstream part of the first supply path to a downstream part, and an upstream part of the first supply path. A first three-way valve that can be switched between a state in which is connected to the first branch path, a second supply path that guides the second molten resin to the second port, and a branch from the middle of the second supply path. And a second branch path for discharging the second molten resin to the outside, A second switch that is provided at a branch point of the branch route and can switch between a state in which the upstream portion of the second supply route is connected to the downstream portion and a state in which the upstream portion of the second supply route is connected to the second branch route And a nozzle for an injection molding machine equipped with the three-way valve, the second three-way valve shuts off the middle of the second supply path, and the first three-way valve upstream of the first supply path. A part connected to a downstream part, and a state in which the first molten resin is supplied into the nozzle body, and the middle of the first supply path is blocked by the first three-way valve, and the second three-way Changing the molten resin used by connecting the upstream portion of the second supply path to the downstream portion with a valve and switching between supplying the second molten resin into the nozzle body. An injection molding method, which comprises: 6. The injection molding is performed using the first molten resin while the upstream portion of the first supply path is connected to the downstream portion via the first three-way valve, An upstream portion of the second supply path is connected to the second branch path via a second three-way valve to purge the second molten resin, and the second via the second three-way valve to the second With the upstream portion of the supply path connected to the downstream portion, while performing the injection molding using the second molten resin, through the first three-way valve and the upstream portion of the first supply path The injection molding method according to claim 5, wherein the first branched path is connected to purge the first molten resin. 7. A first flow path and a second port, which are connected to the back surface of the mold through a discharge port provided at the tip, have a first port and a second port, and connect the first port and the discharge port. A nozzle body in which a second flow path connecting the discharge ports is formed, a first supply path for guiding the first molten resin to the first port, and a first opening / closing provided in the middle of the first supply path. A mechanism, a second supply path for guiding the second molten resin to the second port, and a second opening / closing mechanism provided in the middle of the second supply path, using a nozzle for an injection molding machine, The second opening / closing mechanism shuts off the middle of the second supply path, and the first opening / closing mechanism connects an upstream portion of the first supply path to a downstream portion to connect the first molten resin to the nozzle body. And the state of the inside of the first supply path by the first opening / closing mechanism. By shutting off and connecting the upstream portion of the second supply path to the downstream portion by the second opening / closing mechanism, and switching between the state of supplying the second molten resin into the nozzle body. An injection molding method, characterized in that the molten resin used is changed. 8. A first flow path and a second port, which are connected to the back surface of the mold through a discharge port provided at the tip, have a first port and a second port, and connect the first port and the discharge port. A nozzle body in which a second flow path connecting the discharge ports is formed, a first supply path for guiding the first molten resin to the first port, and a branch in the middle of the first supply path A first branch path for discharging the molten resin to the outside, a state of being provided at a branch point of the first branch path and connecting an upstream part of the first supply path to a downstream part, and an upstream part of the first supply path. A first three-way valve that can be switched between a state in which is connected to the first branch path, a second supply path that guides the second molten resin to the second port, and a branch from the middle of the second supply path. And a second branch path for discharging the second molten resin to the outside, A second switch that is provided at a branch point of the branch route and can switch between a state in which the upstream portion of the second supply route is connected to the downstream portion and a state in which the upstream portion of the second supply route is connected to the second branch route A three-way valve, a first injection unit connected to the upstream side of the first supply path, and a second injection unit connected to the upstream side of the second supply path. Injection molding machine. 9. The first flow channel is a hole-shaped flow channel formed on the central axis of the nozzle body, and the second flow channel is an annular flow channel formed around the first flow channel. The injection molding machine according to claim 8, wherein the injection passage is a passage, and the first flow passage and the second flow passage meet before the discharge port. 10. The nozzle body is composed of an outer nozzle and an inner nozzle incorporated in the outer nozzle, the discharge port is formed at a tip of the outer nozzle, and the first flow path is the inner nozzle. The injection molding machine according to claim 8, wherein the injection path is formed on a central axis of a nozzle, and the second flow path is formed between an outer peripheral surface of the inner nozzle and an inner peripheral surface of the outer nozzle. . 11. The first opening / closing valve provided on the first branch path, and the second opening / closing valve provided on the second branch path are further provided. The injection molding machine according to any one of 10 to 10.