JPH0751299B2 - Eject control method of injection molding machine - Google Patents

Description

TECHNICAL FIELD The present invention relates to an eject control method of an ejector device in an injection molding machine for taking out a molded product from a mold.

2. Description of the Related Art In an injection molding machine, after mold clamping, molten resin is injected into the mold, and after cooling, the mold is opened. At that time, as a method of removing the molded product from the mold, a method of ejecting the molded product from the mold by ejecting the ejector rod into the mold by an ejector device and then returning the rod is performed once to several times. , In combination with the automatic molded product take-out device, the ejector device advances the ejecting rod, and at this advanced position, the automatic take-out device stops at the fixed time required for taking out the molded product, and retracts the ejecting rod after a certain time elapses. There was a way to make it happen.

Problems to be Solved by the Invention In the latter method, the stop time for stopping the protruding rod at the forward position is fixed and fixed to a certain time by a sequencer or the like. Therefore, if you change the automatic take-out device, the ejector bar retracts before the automatic take-out device takes out the molded product, and the molded product cannot be taken out, or even if the automatic take-out device has already taken out the molded product. In spite of this, since the protruding rod is retracted after waiting for a certain period of time, the cycle time of the entire injection molding operation is lengthened and it is impossible to operate efficiently. Also,
Even if it is necessary to operate in association with eject operation such as thermal transfer molding, if the stop time at the forward position of the ejector rod is set to a fixed time, a problem occurs due to time limitation, and the use of the injection molding machine However, there was a problem of lacking flexibility in expansion.

In view of this, the present invention provides an eject control of the injection molding machine, in which the stop time at the forward position of the protruding rod is arbitrarily set and the protruding rod is retracted based on a backward start command from the outside of the injection molding machine. To provide a method.

Means and Actions for Solving the Problems In an eject control method of an injection molding machine in which an ejector device driven by a servo motor is driven and controlled by a numerical control device, the numerical control device drives the servo motor to move a protruding rod. After it is moved forward and stopped at a predetermined position, the backward movement start command signal is received from the outside to start the backward movement of the protruding rod, so the stop time at the protruding position of the protruding rod is arbitrary. Even if a device related to eject operation such as a product take-out device is attached, the interface is maintained and the function of the injection molding machine is expanded.
The application can be expanded.

Embodiment FIG. 1 is a control block diagram of a main part of an injection molding machine for carrying out the present invention, and 10 is a numerical controller (hereinafter referred to as NC device) for controlling the injection molding machine, which is a microprocessor for NC (hereinafter CPU 11) and a CPU 12 for a programmable machine controller (hereinafter referred to as PMC).
An RO that stores an eject operation program, which will be described later, and a sequence program for each operation of the injection molding machine in the CPU 12 for use
The M15 is connected, and the NC CPU 11 has a ROM 14 that stores a management program that controls the injection molding machine as a whole and servos that control the servo motors for each axis such as injection, clamp, screw rotation, and ejector. The circuit 17 is connected via the servo interface 16. Reference numeral 41 is an ejector device, 40 is a servomotor for driving the ejector device, which is connected to the servo circuit 17, and by driving the servomotor 40, a protruding rod of the ejector device 41 is moved forward and backward to form a molded product. To take out. In addition, in FIG. 1, the servo motor of the ejector device is shown.
Only 40 is shown and the other servomotors are omitted. 18
Is a non-volatile shared RAM with a backup power supply,
It stores the NC program that controls each operation of the injection molding machine, various set values, parameters, etc. 13 is a bus arbiter controller (hereinafter referred to as BAC), which is NC
Each bus of the CPU 11 for PMC and the CPU 12 for PMC, the shared RAM 18, the input circuit 20, and the output circuit 21 is connected, and the bus used is controlled by the BAC 13. Further, a data input device with display device (referred to as CRT / MDI) 30 is connected to the operator panel controller 19 to the BAC 13. An external device 50 such as an automatic product take-out device is connected to the input circuit 20 and the output circuit 21. Reference numeral 22 is a RAM used by the NC CPU 1 for primary storage of data during various processes, and 23 is RAM used by the PMC CPU 12 for temporary storage of data during various processes.

Next, the operation of this embodiment will be described with reference to the operation processing flowchart of FIG.

When injection and cooling are performed, the mold is opened, and the moving platen reaches the eject start position, the PMC CPU 12 reads the ROM 15
Read out the sequence program of eject operation,
First, the ejector forward command is written in the shared RAM 18 (step S1). The CPU CPU11 for NC has a shared RAM18 for ejector forward command
When reading that written in, the pulse distribution for advancing the ejector is started, the servo motor 40 is driven through the servo interface 16 and the servo circuit 17, the ejector device 41 is operated, and the ejection rod is advanced. . Then, when the pulse distribution is completed and the ejector rod reaches the forward position, NC
CPU 11 writes the completion of pulse distribution to shared RAM 18.

On the other hand, the PMC CPU 12 monitors whether or not the completion of pulse distribution has been written in the shared RAM 18, that is, whether or not the eject forward position has been reached (step S2). At the forward position, output circuit 21
Outputs a signal indicating the ejector forward position (step
S3). External device to which the signal is input via the output circuit 21
50 starts operation, and if it is an automatic product take-out device, it takes out the molded product from the mold. Meanwhile ejector device
41 has stopped its drive, the protruding bar is stopped at the forward position, and the PMC CPU 12 monitors whether or not a backward start command signal is input to the input circuit 20 from the external device 50 (step S4). ). An external device 50, such as an automatic product take-out device, takes out the molded product and outputs a backward command signal as a take-out completion signal.
If output to the input circuit 20 of the NC device 10, the PMC CPU 12 is shared
The ejector retract command signal is written in RAM18, and the CPU 11 for NC reads that this signal has been written (step S5),
Start the pulse distribution for retracting the ejector rod of the ejector device 41, the servo interface 16, the servo circuit 17,
When the ejector rod of the ejector device 41 is retracted via the servo motor 40 and the pulse distribution is completed and the ejector rod reaches the retracted position, the NC CPU 11 writes a pulse distribution completion signal in the shared RAM 18, and the PMC CPU 12 writes it. If read (step S
6), the eject operation ends.

In the above embodiment, the external device 50 is described as an example of a product take-out device, but another device, for example, a film take-up device in thermal transfer molding may be used, and an output signal from the output circuit 21 indicating the ejector advance position state. Thus, a plurality of devices, for example, the product take-out device and the film take-up device may be operated, and the operation completion signal of whichever is slower may be input to the input circuit 20 to retract the ejecting rod of the ejector device.

As described above, in the present invention, after the ejector rod of the ejector device is stopped at the forward position, the ejector rod is retracted by the retract start command signal from the external device. Since it can interface with any related type of external equipment, it can be easily applied even if the external equipment is changed to a different type or another external equipment is added. Can be efficiently expanded and operated.

[Brief description of drawings]

FIG. 1 is a block diagram of an essential part of an embodiment of the present invention, and FIG. 2 is a flowchart of an eject operation in the embodiment. 10 ... Numerical control device, 40 ... Ejector device servomotor, 41 ... Ejector device, 50 ... External device.

Claims (1)

[Claims] 1. An eject control method for an injection molding machine, wherein an ejector device driven by a servo motor is drive-controlled by a numerical control device, wherein the numerical control device drives the servo motor to move a protruding rod forward. An eject control method for an injection molding machine, which is configured to start a retreat of the protruding rod upon receiving a retreat start command signal from the outside after stopping.