JPH0443300Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention presses an injection nozzle against the opening of a resin inflow hole formed on the mold separation surface of a closed mold, and injects resin from the injection nozzle. The present invention relates to a thread-pulling resin cutting device for cutting thread-like resin extending from the injection nozzle to the resin inflow hole of an injection molding machine.

[Prior Art] As this type of injection molding machine, for example, the horizontal mold clamping/vertical injection machine shown in FIGS. 4 and 5 is known. That is, a fixed platen 2 is fixed on a frame main body 1, and a movable platen 3 is provided above the frame 1, which is horizontally movable in directions toward and away from the fixed platen 2. And moving board 3
By moving the mold M toward and away from the fixed platen 2, the mold M is clamped and opened and closed.

The mold M includes a fixed mold M1 fixed to a fixed platen 2 and a movable mold M2 fixed to a movable plate 3, and the mold separation surface PL between the fixed mold M1 and the movable mold M2
A resin inflow hole H communicating with the cavity C is formed in the hole.

In this injection molding machine, a mold M is attached to a fixed platen 2 and a movable platen 3 with the resin inflow hole H facing upward. An injection nozzle 4 is provided that can move toward and away from the opening H1 (up and down in FIG. 1). A heater (not shown) is wound around the injection nozzle 4, and the resin formed at the tip of the injection nozzle 4 is heated while keeping the melted resin at a constant temperature in a heating cylinder (not shown). The resin is injected from the outlet 4a to the resin inlet H.

In the injection molding machine configured as described above, when injecting resin into the mold M, first the movable platen 3
is moved to the fixed platen 2 side to close the mold M, and the movable platen 3 is further pressed to the fixed platen 2 side to clamp the mold M. Then, the injection nozzle 4 is pressed against the opening H1 of the resin inlet hole H of the mold M, and the resin is injected into the cavity C from the resin outlet 4a of the injection nozzle 4 through the resin inlet hole H. In addition, when taking out the molded product S formed by cooling and solidifying the resin in the cavity C, first move the injection nozzle 4 upward and separate the injection nozzle 4 from the opening H1 of the resin inflow hole H. Thereafter, the movable platen 3 is moved away from the fixed platen 2 to separate the mold M from the mold separation surface PL, and the molded product S is ejected from the movable mold M2 by an ejector (not shown) and dropped.

[Problem to be solved by the invention] However, in the injection molding machine described above, when the injection nozzle 4 is moved upward from the opening H1 of the resin inflow hole H, it is pulled by the solidified resin in the resin inflow hole H1. The molten resin in the injection nozzle 4 may be pulled out in the form of a thread, and the molded product S may be suspended from the injection nozzle 4 by the thread-like resin S1. If this happens, the molded product S will be caught between the stationary mold M1 and the movable mold M2 during the next mold clamping, making it impossible to carry out the next molding, hindering continuous molding, and There is a risk of damaging it.

The present invention was developed in view of the above circumstances, and it cuts the stringy resin from the injection nozzle to prevent the molded product from being caught between the fixed mold and the movable mold during the next mold clamping. The purpose is to provide a resin cutting device.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention provides a method in which the direction in which the resin inflow hole approaches and separates from the opening of the resin inflow hole formed on the mold separation surface between the fixed mold and the movable mold of a closed mold is provided. The tip of the injection nozzle is pressed against the opening of the resin inlet hole to inject resin into the mold when the mold is closed, and the injection nozzle is movable when the mold is opened. In an injection molding machine configured to move the nozzle backward to separate the injection nozzle from the opening, thread-like resin extending from the injection nozzle to the resin inflow hole that is generated when the injection nozzle is moved away from the opening. A string pulling resin cutting device for cutting, wherein a base end is fixed to the movable mold or a member that moves together with the movable mold, and a distal end is retracted from an opening of a resin inflow hole of the mold and the opening. A rod-shaped member is provided between the mold and the injection nozzle, and is formed so as to move together with the movable mold and cross the opening when the mold is opened.

[Operation] In the present invention, when the movable mold moves away from the fixed mold when the mold is opened, the tip of the rod-shaped member crosses the opening between the injection nozzle and the opening of the resin inflow hole. At this time, the stringy resin is pulled by the tip of the rod-like member, and the stringy resin is cut from the nozzle.

[Embodiments] Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 3. However, elements common to those of the conventional example shown in FIGS. 4 and 5 are given the same reference numerals and their explanations will be omitted.

First Embodiment A first embodiment of the present invention will be described with reference to FIGS. 1 and 2.

As shown in these figures, the movable mold M2 of the mold M
A hooking jig (rod-shaped member) 5 is attached to the shaped surface.

The hooking jig 5 is made of an elongated steel material with a circular cross section, and has a base end 5a bent into an annular shape, into which a bolt 6 is inserted. In addition, the tip portion 5b of the hooking jig 5
In the state in which the base end 5a is fixed to the upper surface of the movable mold M2 with the bolt 6, the opening H1 of the resin inflow hole H of the closed mold M is surrounded from the fixed mold M1 side, and the opening H1 is removed from the opening H1. Retracted injection nozzle 4
It is located between the tip of the mold M1 and the opening H1, and is formed in an arc shape so as to cross the opening H1 as the movable mold M1 moves when the mold is opened.

In the stringing resin cutting device having the hooking jig 5 formed as described above, when the mold M is opened, the hooking jig 5 moves together with the movable mold M2 and the pulling When the tip 5b of the hanging jig 5 crosses the opening H1 of the resin inflow hole H and the injection nozzle 4 leaves the opening H1, it pulls the stringy resin S1 extending from the injection nozzle 4, and the string Pull resin S
1 is cut from the tip of the injection nozzle 4.

Therefore, according to the stringy resin cutting device configured as described above, even if the stringy resin S1 extends from the injection nozzle 4 and connects to the molded product S, the stringy resin cutting device does not cut the stringy resin when the mold is opened. Since the stringy resin S1 can be cut with the tool 5, the problem of the molded product S hanging from the injection nozzle 4 and being caught between the fixed mold M1 and the movable mold M2 during the next mold clamping can be prevented. can do.

In addition, in the first embodiment, the hooking jig 5 was configured to be fixed to the movable mold M2.
It goes without saying that the hooking jig 5 may be fixed to the movable platen 3 or a member that moves together with the movable mold M2, like the movable platen 3.

Further, the tip portion 5b of the hooking jig 5 may be provided so as to be in contact with the fixed mold M1 or the movable mold M2, or may be provided so as to be in contact with the tip of the injection nozzle 4. In this case, the resin extending outward from the opening H1 of the resin inflow hole H and the resin drawn out from the resin outlet 4a of the injection nozzle 4 can be scraped off, and the stringy resin from the injection nozzle 4 can be scraped off. S1 can be reliably cut.

Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIG.

In this embodiment, in addition to the hooking jig 5, an air nozzle 7 that blows out air is provided.

The air nozzle 7 is formed into a pipe shape, and its base end is fixed to the upper end surface of the fixed platen 2 via a fixing member 8, and its tip end is connected to the opening H1 of the resin inflow hole H of the mold M. and the resin outlet 4a of the injection nozzle 4 toward the center of the line.
The base end of the air nozzle 7 is connected to an air pressure source 10 via a solenoid valve 9. Solenoid valve 9
is configured to have two ports and two positions that block the flow of air to the air nozzle 7 at the neutral position and allow the flow of air to the air nozzle 7 at the operating position when the solenoid 9a is energized.

In the stringing resin cutting device configured as described above, the stringing resin S1 extending from the injection nozzle 4 is rapidly cooled and solidified by the air jetted from the air nozzle 7. For this reason, when the string-pulling resin S1 is pulled with the hooking jig 5, the string-pulling resin S1 solidifies and becomes difficult to stretch.
The threaded resin S1 is easily cut by the hooking jig 5.

Therefore, according to the stringing resin cutting device configured as described above, the stringing resin S1 can be cut more reliably.

[Effects of the invention] As explained above, according to the invention, when the movable mold is separated from the fixed mold when the mold is opened, the tip of the rod-like member moves between the injection nozzle and the opening of the resin inflow hole. Since it crosses the opening, even if stringy resin is formed extending from the injection nozzle toward the resin inflow hole when the injection nozzle is retreated from the opening of the resin inflow hole, the stringy resin can be removed by the tip of the rod-shaped member. It can be pulled off and cut from the injection nozzle. Therefore, it is possible to prevent the molded product from being caught between the fixed mold and the movable mold during the next mold clamping.
Furthermore, since the rod-shaped member is cut by moving the movable platen, there is no need to provide a special device such as an actuator for the cutting operation, and there is a practical advantage that the cutting operation can be carried out extremely easily.

[Brief explanation of drawings]

Figures 1 and 2 are diagrams showing a first embodiment of the present invention, in which Figure 1 is a perspective view showing a string-pulling resin cutting device, and Figure 2 is a string-pulling resin cutting device during mold opening. FIG. 3 is a side view of a string drawing resin cutting device shown as a second embodiment, and FIGS. 4 and 5 are views of an injection molding machine shown as a conventional example. is a side view, and FIG. 5 is a side view showing the state when the mold is opened. 4... Injection nozzle, 5... Hooking jig (rod-shaped member), 5a... Base end, 5b... Tip, H...
...Resin inflow hole, H1...Opening, M...Mold, M
1...Fixed type, M2...Movable type, PL...Mold separation surface, S1...String resin.

Claims (1)

[Scope of utility model registration request] It has an injection nozzle that can move toward and away from the opening of the resin inflow hole formed on the mold separation surface between the fixed mold and the movable mold of the closed mold, and when the mold is clamped, the tip of the injection nozzle The injection nozzle is configured to press against the opening of the resin inflow hole to inject the resin into the mold, and to move the injection nozzle backward to separate the injection nozzle from the opening when the mold is opened. A thread-pulling resin cutting device for cutting string-like resin extending from the injection nozzle to the resin inflow hole that is generated when the injection nozzle is separated from the opening of the molding machine, the base end of which is cut by the movable type or the movable type. It is fixed to a member that moves with the mold, and has a distal end between an opening of the resin inflow hole of the mold and an injection nozzle that is retracted from the opening, and moves with the movable mold when the mold is opened to close the opening. 1. A string-pulling resin cutting device characterized by comprising a rod-shaped member formed to cross a section.