JPH10315238A - Flowing behavior analyzing device for foamable resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a foaming starting point by fixedly arranging in a row a plurality of reflection type optical sensors at an upper transparent portion of a mold and input pulse signals generated when a resin passes directly under the sensors into a computer for processing so as to measure the foaming speed in a real-time fashion. SOLUTION: Reflection type optical sensors R0 to R8 are mounted on an upper transparent mold of a metal mold 1 and a resin is injected from an injection port 2. The mounting position of the sensor may be at the position of the injection port 2 or may be freely changed to other positions. When a foamable resin is started to be injected from the injection port 2, the computer starts to collect data, pulse signals are generated when the resin passes directly under the sensors R0 to R8, and the singals so generated are then fed into the computer. The computer obtains an approximate equation representing the drift velocity of the resin based on the pulse signals so fed and then obtains a foaming starting point using the equation so obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding apparatus for a molding test of an expandable resin, and more particularly to a flow behavior after injection of a resin inside the mold apparatus. It is about seeking.

[0002]

2. Description of the Related Art The flow behavior of a resin in a mold is one of indices for evaluating the properties of the resin, but it has been difficult to directly measure the resin so far. Was very inaccurate.

[0003]

Although it is difficult to grasp the flow behavior of the foamable resin in detail by visual observation, high accuracy can be obtained if there is a means for directly measuring the behavior. However, the flowing foamable resin has an indeterminate and unstable shape and needs to be non-contact in order to measure it without affecting its behavior.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a mold apparatus for a foaming resin molding test, wherein the upper mold (wagata) has a transparent plate and has a variable mounting position on its upper surface. When a plurality of reflective photoelectric sensors are mounted and foaming resin is injected into the mold using an injection machine, the sensor generates a pulse signal as soon as the resin passes directly below the reflective photoelectric sensor, and the pulse signal is generated in real time. Collects data on flow behavior in a non-contact manner by computer processing,
This is achieved by an apparatus including a computer and a reflective photoelectric sensor capable of determining a foaming start point.

In the present invention, in order to non-contactly measure the behavior of a resin which flows into a mold while foaming while being injected into a mold,
A plurality of reflective optical sensors are arranged on the upper part of the transparent upper mold, and the foaming speed is measured in real time by taking in a computer a pulse signal generated immediately after the resin passes directly below the reflective optical sensor. The starting point of foaming is determined.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION After injecting a foamable resin into a mold,
A pulse signal is input to a computer from a plurality of reflective photoelectric sensors attached to the upper part of the transparent upper mold of the mold each time the resin passes directly below the reflective photoelectric sensors. When the computer receives the signal, it records the time, and the distance from the injection port to the sensor is measured in advance and recorded in the computer. Use to obtain the starting point of foaming.

[0007]

Embodiments will be described below with reference to the drawings. FIG. 1 is an overall view of a mold and a computer system. In the mold 1, the reflection type optical sensors R <b> 0 to R <b> 8 are attached to the upper mold, and the resin is injected from the injection port 2. The mounting position of the reflection type optical sensor can be freely changed according to the position of the injection port or the prescription of the sample. When the foaming resin starts to be injected from one injection port, the computer starts collecting data, and a pulse signal is sent to the computer as soon as the resin passes just below the sensor. When the computer receives the pulse signal, it obtains the time at that point in time and creates an approximate expression representing the relationship between the time and the position of the sensor. The approximate expression uses a root curve before foaming starts and a logistic curve after foaming starts.

[0008]

(Equation 1)

[0009]

## EQU2 ## The root curve Yt = a1２Xt + a2 The foaming start point is substantially determined by the formulation of the foamable resin to be injected.
Considering that, determine the sensor mounting position. The intersection of the above two curves, or the closest point, is the foaming start point. FIG. 2 shows a curve representing the foaming speed obtained by actually performing the foaming test.

[0010]

According to the present invention, the foaming speed and foaming start point of the foamable resin, which could not be achieved by the prior art, can be determined with high precision.

[Brief description of the drawings]

FIG. 1 is a view of a mold as viewed from above.

FIG. 2 is a graph of an approximate expression of a foaming speed. The horizontal axis represents time, the vertical axis represents the position of the sensor, and the intersection of the solid line and the dotted line is the foaming start point.

[Explanation of symbols]

 1 Mold body 2 Injection port R0 ~ R8 Reflection type photoelectric sensor

Claims (1)

[Claims] 1. A mold apparatus for a foaming resin molding test,
The upper mold is made of a transparent plate, a plurality of reflective photoelectric sensors with variable mounting positions are mounted on the upper surface, and when the foaming resin is injected into the mold using an injection machine, the resin is reflected. The sensor generates a pulse signal as soon as it passes directly below the photoelectric sensor, and the computer processes the pulse signal in real time to collect data on the flow behavior in a non-contact manner and determine the starting point of foaming. And a computer.