JPH054263A - Quality controlling method based on uneven color of injection-molded article - Google Patents

Abstract

PURPOSE:To easily discriminate the quality of uneven color with a glossmeter without adopting the conventional judgement of uneven color by an expert. CONSTITUTION:The quality controlling method concerned consists of the measurement of the glossiness of a molded article, which is injected from an injection molder 1 and sent from an unloader 2 with a conveyor 3, with a glossmeter 5 and the discrimination of the quality of uneven color on the basis of the relationship between pre-set glossiness and uneven color.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a quality control method based on color spots of injection molded products.

[0002]

2. Description of the Related Art Conventionally, Japanese Patent Laid-Open No. 3-82516 has been proposed as a method for controlling the quality of injection molded products. The quality control of the injection molded product shown in this publication measures the surface temperature of the molded product after injection molding and estimates the quality based on the correlation between the surface temperature of the molded product and the quality measured in advance. It is a thing. Moreover, the operating conditions and the like of the injection molding machine are changed using the measurement results.

[0003]

For some injection-molded products, it is not sufficient to control the quality by temperature as in the prior art, and it is necessary to judge the quality based on the color spots on the surface of the injection-molded product. There were cases. In such a case, a skilled person determines the color spot, but it is a problem that it is very difficult to train such a skilled person thereafter. The present invention intends to provide a simple quality control method for an injection-molded article having such a color spot as a judgment element.

[0004]

Therefore, according to the present invention, the glossiness of a molded article injected by an injection molding machine is measured by using a glossiness meter, and the glossiness is determined by a preset relationship between the glossiness and the glossiness. The quality of the color spot is determined, and this is used as a means for solving the problem.

[0005]

[Function] The injection molded product is measured with a gloss meter. There is a certain correlation between the measured value of the gloss meter and the color spot on the surface of the molded product, and the quality based on the color spot is controlled by this correlation.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below with reference to the accompanying drawings. FIG. 1 shows one embodiment of the present invention. In FIG. 1, 1 is an injection molding machine, 2 is a take-out machine that conveys a molded product discharged from the injection molding machine to a conveyor 3, 3 is a conveyor, 4 is a molded product recognition sensor, 5 is a gloss meter, 6 Is a control panel, 7 is a shooter for discriminating non-defective products, 8 is a defective stocker, and 9 is a non-defective stocker.

Next, the operation will be described with reference to FIG. 1. The molded product injected by the injection molding machine 1 is conveyed by the conveyor 3 via the take-out machine 2. Then, the molded product recognition sensor 4 such as a photoelectric sensor arranged in the middle of the conveyor 3 recognizes and detects the molded product 10, and the detection signal is sent to the control panel 6. The control panel 6 reads the detection value of the gloss meter 5 based on this signal. Next, the quality of color spots that correlate with the value of a gloss meter, which will be described later, stored in advance is judged, and the judgment shooter 7 is controlled.
The non-defective product is controlled to be sent to the non-defective product stocker 9.

The gloss meter 5 is a specular gloss measuring method (J
According to ISZ8741), the schematic measurement concept is shown in FIG.
Shown in. As for the specular gloss, a light beam having a specified opening angle is incident on the surface of the molded product at a specified incident angle, and a light beam having a specified opening angle reflected in the specular reflection direction is measured by a light receiver. It is assumed that the aperture S ₁ of the light source is located at the focal position of the lens L ₂ and a clear image is formed at the center of the aperture S ₂ of the light receiver when a mirror surface is placed at the position of the sample T. The incident angle θ is an angle formed by a line connecting the center of the opening S _{1 and} the center of the lens L ₂ (principal point of the lens) and the normal line of the sample T.

On the other hand, the light receiving angle θ'is the angle formed by the line connecting the center of the aperture S _{2 and} the center of the lens L ₃ (principal point of the lens) and the normal line of the sample T. Also, the opening angles α ₁ and α ₂ are defined by the opening S
Angle at which ₁ and S ₂ are stretched at the positions of lenses L ₂ and L ₃ , opening angle α
₁ 'is the image S ₁ of the opening S _1' and angle spanned by the position of the lens L _3. The optical axes of the incident side and the light receiving side shall intersect at the sample surface. For each of the above variables, the specular gloss is GS
It is calculated by (θ) = (φS / φos) × (glossiness of the reference surface used).

Next, FIG. 2 shows the correlation between glossiness and color spot A
A BS resin molded product is shown as an example. As is clear from the figure, the glossiness and the color spot (visual evaluation) have a substantially linear relationship. In this example, the higher the glossiness, the less the color spots, and the product can be judged to be a good product. Also, although the non-defective product limit regarding the glossiness differs depending on the molded product, considering the non-defective product limit on the safe side, X = 4.5 (glossiness Y is 54%) is set in FIG. As a result, the gloss level of the gloss meter
By comparing with the value based on the detected value in (3), it is possible to easily judge the quality of the molded product.

FIG. 3 is a glossiness regression graph showing the relationship between the filling time (seconds) in the injection molding machine and the injection resin (ABS resin) temperature. That is, the glossiness Y is expressed as a parameter. The glossiness Y is the filling time t _F
(Seconds) and injection resin temperature T ₁ ° C. Y = 8.897−
^{_{0.010t F 3 + 4.511 × 10 8}} / T 1 can be represented by ³ of the regression equation. In addition, when the resin temperature is low, the influence of the filling time largely contributes to the glossiness. As is clear from FIG. 3, for example, when the injection resin temperature is 210 ° C.,
In order to obtain a good product, the filling time needs to be 7.1 seconds or less.

From the above, by measuring the gloss Y, it is possible to easily determine whether or not the molded product is a good product, and the gloss Y, the filling time t _F (seconds) and the injection resin temperature T ₁
By storing the relationship with the temperature in the control panel 6 in advance, so-called feedback control is performed to change the injection resin temperature T ₁ in the injection filling time t _F range of the injection molding machine 1 when a defective product occurs. This can be done easily and the incidence of defective products can be reduced.

[0013]

As described in detail above, the quality control method based on the color spots of the injection molded product of the present invention is to measure the glossiness of the molded product injected by the injection molding machine using the gloss meter. By. That is, since the relationship between the glossiness and the color spot is known, if the relationship is stored in the control panel in advance and compared with the measured value of the glossiness, the quality of the color spot can be easily determined. Therefore, according to the present invention, it is possible to control the quality of color spots of injection-molded products by a simple method.

[Brief description of drawings]

FIG. 1 is a plan view of an apparatus for carrying out a quality control method based on color spots of an injection-molded product according to an embodiment of the present invention.

FIG. 2 is a diagram showing a correlation between glossiness and color spots.

FIG. 3 is a diagram showing a relationship between a filling time (second) in an injection molding machine and an injection resin temperature.

FIG. 4 is a conceptual diagram illustrating a specular gloss measurement method.

[Explanation of symbols]

 1 Injection molding machine 2 Take-out machine 3 Conveyor 4 Molded product recognition sensor 5 Gloss meter 6 Control panel 7 Discrimination shooter

Claims (1)

Claims: 1. A molded product injected by an injection molding machine is used to measure the glossiness by using a gloss meter, and the quality of the color spot is determined based on the relationship of the color spot to the preset glossiness. A quality control method based on color spots of an injection-molded product, characterized by: