JPH0530901Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field This invention relates to an open/close signal for a shut-off valve in an injection molding machine.

(b) Prior Art In a conventional shut-off valve, as shown in FIG. 3, a timer (not shown) is started at the same time that the actuator 4 enters the full open operation, and resin is injected when the timer expires.

Further, when the actuator 4 enters a fully closing operation upon receiving a signal indicating that the timer has expired after the pressure is maintained, the timer is started at the same time, and the resin is plasticized upon receiving the signal indicating that the timer has expired.

(c) Problems to be solved by the invention In this conventional shut-off valve, in order to perform injection at the timer expiration signal without confirming that the shut-off valve is fully open, the valve 10
There were problems in that the molded product would become a shot shot when it was half open, and it could not be injected when it was fully closed.

Furthermore, during plasticization, the valve 10 becomes half-open or fully open, causing molten resin to drip from the nozzle tip, which requires the molding machine to be stopped to investigate the cause.

The present invention aims to solve such problems.

(d) Means for Solving the Problems In the present invention, a nozzle 2 is attached to the tip of a cylinder head 1 of an injection molding machine, a valve 10 is inserted into the hole of the nozzle 2, and the valve 10 is inserted through a lever 3 joint 11. a limit switch 9 that sends a signal to the actuator 4 to start injection when the valve 10 is fully opened;
The above problem is solved by installing a limit switch 8 that sends a signal to start plasticizing when the valve 10 is fully closed, and installing a cam 7 on the joint 11 that operates the limit switches 8 and 9. Solve.

(e) Operation When the shutoff valve configured as described above changes from fully closed to fully open, the cam activates the limit switch, and the signal starts injection.

Next, when the state changes from fully open to fully closed, the cam activates the limit switch, and plasticization begins based on the signal.

(F) Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

1 and 2 are diagrams showing a shutoff valve according to the present invention. In the drawing, reference numeral 1 indicates a cylinder head of an injection molding machine, and a nozzle 2 is attached to the tip of the cylinder head 1. As shown in FIG.

A valve 10 is inserted into the hole of the nozzle 2, and this valve 10 is connected to the actuator 4 via the lever 3 joint 11. This actuator 4 is attached to the cylinder head 1 via a bracket 5. Limit switches 8 and 9 are installed on the actuator 4 via a limit switch mounting plate 6.

A cam 7 is attached to the joint 11 and is set to operate in response to the fully closed and fully open positions of the limit switches 8 and 9.

The shut-off valve with opening/closing signal for an injection molding machine according to the present invention is constructed as described above.
The operation will be explained below.

First, when the shut-off valve changes from fully closed to fully open, the cam 7 activates the limit switch 9, and injection begins based on that signal.

Next, when the shutoff valve changes from fully open to fully closed, the cam 7 operates the limit switch 8, and plasticization begins based on the signal.

Therefore, full opening and closing of the valve 10 is reliably ensured by the signals from the limit switches 8 and 9.

In addition, in this invention, limit switch 8,
Although 9 is installed on the actuator 4 side, the limit switches 8 and 9 may be installed on the joint 11 side, and the cam 7 may be installed on the actuator 4 side.

(g) Effects of the invention As explained above, according to the invention, by installing a limit switch on the shut-off valve that allows confirmation of the fully open and fully closed positions, it is possible to ensure that the shut-off valve is in the fully open and fully closed positions. Since it can be operated, problems such as short shots, inability to inject, and resin dripping from the nozzle tip have been eliminated.

[Brief explanation of the drawing]

Figure 1 shows the shut-off valve of the embodiment of the present invention in a fully closed state, Figure 2 shows the shut-off valve of the embodiment of the present invention in its fully open state, and Figure 3 shows the conventional shut-off valve. This is a diagram. 1... Cylinder head, 2... Nozzle, 3...
Lever, 4... Actuator, 5... Bracket, 6... Limit switch mounting plate, 7... Cam, 8... Limit switch (for fully closed), 9...
Limit switch (fully open), 10...valve,
11...Joint.

Claims (1)

[Scope of claim for utility model registration] Nozzle 2 at the tip of cylinder head 1 of an injection molding machine
and insert the valve 10 into the hole of the nozzle 2, and the valve 10 is connected to the actuator 4 via the lever 3 joint 11. A limit switch 9 that sends a signal to start injection when the valve is fully opened, and a limit switch 8 that sends a signal to start plasticizing when the valve 10 is fully closed are installed.
A shut-off valve with an opening/closing signal for an injection molding machine, characterized in that a cam 7 for operating the injection molding machine is installed.