JPS6042021A - Monitoring of mold temperature - Google Patents

Abstract

PURPOSE:To obtain a high-quality molded article in a good yield keeping mold temperature under control by a method wherein when the mold temperature detected only just before an injection molding is within the allowable range, resin is injected into the mold and when the detected value is outside of the allowable range, the injection of the resin is stopped. CONSTITUTION:In a mold temperature monitoring device of an injection molding machine, temperature detecting sensor 1 is mounted on the fixed part 2 of a mold composed of fixed part 2 and movable part 3, while the output of this temperature detecting sensor 1 is connected to temperature monitoring device 5 and this output is converted into the mold temperature and inputted into injection controlling device 6. The injection controlling device 6 controls the mold temperatures from the temperature monitoring device 5 and the injection device 7 connected from other necessary parameter to the following steps. The mold temperature is detected by the temperature detecting sensor 1 just before the injection. When the detected value is within the allowable range the resin is injected by the injection device 7 into the mold and when the detected value is outside of the allowable range the injection of the resin is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for monitoring mold temperature of a mold for an injection molding machine.

Prior Art In the conventional method for monitoring the temperature of a mold for an injection molding machine, the temperature of the mold during operation was constantly monitored.

Here, since the mold temperature increases as the resin is poured into the mold, the setting temperature of the mold determined by the type of resin and the operating conditions of the shape of the mold is used as a reference. It changes like this.

For this reason, it has not been possible to accurately separate and monitor the temperature rise due to resin injection and the variation in mold temperature setting due to equipment abnormality.

Purpose of the Invention Therefore, the present invention determines the quality of molded products in injection molding,
The purpose is to accurately grasp the temperature of the mold to be heated, control the temperature of the mold, and improve the temperature of the mold.

Structure of the Invention Furthermore, the feature of the present invention is that the temperature of the mold is detected not during the entire process of operation, but only at the point immediately before injection, and it is determined whether the detected value is within the allowable range of the mold temperature. It is characterized by the fact that the resin is poured into the mold at the same time.

EXAMPLE The mold temperature monitoring method of the present invention will be explained below with reference to the illustrated example.

As shown in FIG. 1, the mold is composed of a fixed mold 2 and a movable mold 3, and a temperature detection sensor 1 is installed in the fixed mold 2.

The output of this temperature detection sensor 1 is connected to a temperature monitoring device 5, and the output of the temperature detection sensor 1 is converted into a mold temperature and inputted to an injection control device 6.

The injection control device 6 controls the injection device 7 connected to the next stage based on the mold temperature from the temperature monitoring device 5 and other required parameters, and the injection device 7 is appropriately controlled by the injection control device 6 to control the inside of the mold. Pour resin into.

Function: Here, the temperature of the mold is constant controlled to a predetermined temperature according to the operating conditions of the injection molding machine, and as shown in FIG. 2, the temperature changes within a range A as shown in FIG.

Therefore, in order to avoid being affected by temperature changes caused by the injection of resin into the mold, the mold temperature is detected by a temperature detection sensor only immediately before injection starts, and is converted into a temperature signal by the temperature monitoring device 5, which is then converted into a temperature signal by the injection control device 6. Enter.

Here, the injection control device 6 injects the resin into the mold if the mold temperature detection value immediately before the start of injection is within the range of approximately ±1° C. shown in section B.

Additionally, if the detected value deviates from section B, the injection control device 6 stops the injection of resin from the injection device 7 into the molds 2 and 3, and handles the mold temperature abnormality to prevent molding of defective products. do.

Effects of the Invention The embodiment of the mold temperature monitoring method according to the present invention is as described above, and can bring about the following effects.

By monitoring only the temperature of the mold for injection molding machines just before injection, it is possible to accurately control the temperature of the mold (1) to prevent molding of defective products and to improve .

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of the present invention, and FIG. 2 is a graph showing temperature changes in a mold. 1. Temperature detection sensor, 2. Fixed side mold, 3. Movable side mold, 4. Molded product, 5. Temperature monitoring device, 6. Injection control device, 7. Injection device.

Claims (1)

[Claims] A mold temperature monitoring device for an injection molding machine detects the mold temperature only at the point immediately before injection, and when this temperature detection value is within the set tolerance range, resin is poured into the mold and the mold is removed. A mold temperature monitoring method characterized in that when a detected mold temperature value falls outside an allowable range, resin injection is stopped as a mold temperature abnormality.