JPH09174673A - Monitoring device of stretch blow molding machine and method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To find out defective qualities of products in an early stage and take measures for it by analyzing a measured data of various conditions at the time of blow molding, pass-failing products by the result of the analysis, and discharging defective moldings to the outside of a line. SOLUTION: A monitoring device of a stretch blow molding machine measures various conditions at the time of blow molding such as, for example, temperature of preform, temperature pattern in heating zone, drive timing of vertical axis of stretch rod and its speed, and blow mold temperature by a measuring device 1. A storing means 2 stores data from the measuring device 1 and stores control data such as previously set various conditions and standard times, data at the time when excellent products are produced in the past, and data at the time when defective products are produced. A display means 3 displays determination of the measured data and determination of pass or fail. An analyzing means 4 compares and analyzes the measured data and the control data. A determination means 5 determines pass or fail of products by analyzed result. A discharging mechanism 6 discharges moldings which are determined as defective products by the determination means 5 to the outside of a line.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stretch blow molding machine monitoring apparatus and method, and more particularly, to a product quality when a hollow body is molded by stretch blow called a cold parison method or a two-stage method. TECHNICAL FIELD The present invention relates to a stretch blow molding machine monitoring apparatus and method for monitoring various molding conditions that affect the temperature and determining the quality of hollow body products during blow molding.

[0002]

2. Description of the Related Art A stretch blow molding machine for producing hollow bodies, such as bottles, sequentially heats a plurality of preforms, and one or a plurality of preforms heated to a certain temperature condition. The hollow body is subjected to stretch blow molding.

In the heating part of the preform, the temperature of the heater and the passage time of the preform are controlled so that the preform fed into the blow molding machine has a preset temperature distribution.

In the blow molding section, the mold closing timing of the blow cavity mold, the vertical axis driving timing of the drawing rod and its speed, and the blow air introducing timing are controlled. At this time, when the primary and secondary air is introduced as the blow air, the introduction timing of the primary and secondary air is also controlled for each blow mold.

[0005]

In such a stretch blow molding machine, the quality of the product after molding is measured and determined by various inspection devices provided after the stretch blow molding machine. Since there is a time lag between the molding and the measurement / judgment by the inspection device, the product blow-molded during this time becomes a problem. In particular, this problem becomes more important as the production speed becomes higher. Furthermore, when molding a bottle with a handle, the relationship between the strength of the handle attachment portion and the process data is remarkable.

The strength and shape defect of the handle mounting portion, the wall thickness distribution defect, the puncture, and the like may be judged by the process data at the time of stretch blow molding, especially the pattern of the blow air pressure, but this kind of defect is very much. The inspection could be difficult or could lead to troubles in the transportation equipment due to its poor shape. Further, the temperature of the blow molding die is greatly involved in the volume shrinkage of the hollow body product, and it is necessary to control the blow die temperature so as to be within a preset range.

However, this type of blow molding machine is often designed so that the product can be continuously molded by moving or rotating a part of the machine, and process data at the time of blow molding can be continuously calculated. It was difficult to measure.

Therefore, in the present invention, in order to detect and deal with the quality defect of the product at an early stage, various process data from the moving or rotating blow molding machine is processed in real time and the defective molded product is discharged out of the line. It is an object of the present invention to provide a stretch-blow molding machine condition monitoring apparatus and a method therefor.

[0009]

In order to achieve the above object, the condition monitoring device of the stretch blow molding machine of the present invention is a hollow body obtained by heating a preform injection-molded in advance and simultaneously or sequentially stretch blow molding it. A monitoring device of a stretch blow molding machine for molding, a measuring device for measuring various conditions at the time of blow molding, a storage unit for storing data from the measuring device, a display unit for displaying the data, It is characterized by comprising an analyzing means for analyzing the data, a judging means for judging whether the product is acceptable or not based on the analysis result, and a discharging mechanism for discharging the defective molded product out of the line.

Further, in the method of the present invention, one of the condition items measured by the measuring device is blow pressure data which changes with the lapse of time from the reference time, and the pressure change pattern is statistically processed to obtain the hollow pressure data. Judging the quality of the body product at the time of blow molding, further, one of the condition items to be measured by the measuring device is the temperature data of the blow molding die, by statistically processing the change, the hollow body product The feature is that the quality is judged at the time of blow molding.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to the drawings. FIG. 1 is a flow chart showing an example of a processing procedure of the monitoring device of the present invention, and FIG. 2 is a block diagram showing a configuration example of the monitoring device.

The monitoring device of the stretch blow molding machine is equipped with various conditions during blow molding, such as the temperature of the preform, the temperature pattern of the heating zone, the temperature pattern of the preform loaded in the blow cavity mold, and the closing of the blow cavity mold. Timing, vertical axis drive timing of the drawing rod and its speed, blow air introduction timing and its pressure change, integrated value of the primary blow portion until the secondary air is introduced after the introduction of the primary air, and a predetermined value after the introduction of the secondary air Measuring device 1 for measuring timing peak pressure, blow mold temperature, etc.
And a storage means 2 for storing data from the measuring device 1, and also storing management data such as preset various conditions and reference times, past production data of non-defective products, and data upon occurrence of defects. The display means 3 for displaying the measurement data and the quality judgment, the analysis means 4 for comparing and analyzing the measurement data and the management data, the judgment means 5 for judging whether the product is acceptable or not based on the analysis result, and the judgment means 5. A discharge mechanism 6 for discharging a defective molded product determined to be a defective product to the outside of the line.

Further, as shown in FIG. 2, in the blow molding machine, a converter 11 for converting various measured values into a predetermined data format, and the measuring device 1 for measuring data from the converter 11, A control circuit 12 internally provided with arithmetic means such as CPU, ROM, RAM, I / O, a discharge device 13 provided with the discharge mechanism 6, and a transmission device 14 for transmitting input / output signals of the control circuit 12. Outside the blow molding machine, a control circuit 15 having arithmetic means such as CPU, ROM, RAM, I / O, and the like, a transmission device 16 corresponding to the transmission device 14, and the aforementioned A storage device 17 which is a storage means 2 for storing and storing various data, a display device 18 including the display means 3 such as a CRT or a liquid crystal screen, and a keyboard and a control circuit for inputting desired data and the like to the control circuit 15. From An input unit 19 composed of a touch panel for performing various inputs are provided in accordance with sage.

The transmission devices 14 and 16 are multiplex transmission devices, and in particular, for transmitting data with a moving or rotating blow molding mechanism, for example, radio transmission such as radio wave type or optical type. Examples of the device include a wire transmission device such as a slip ring.

The monitoring device constructed as described above discharges defective molded products as described below, and suppresses the generation of defective molded products.

First, the temperature of the preformed preform, the temperature pattern of the heating zone, the temperature pattern of the preform loaded in the blow cavity mold, particularly in the case of a bottle with a handle, the temperature of the part where the handle is entangled is measured. The temperature of the heating zone is controlled so as to meet the preset condition, and the preform or the molded product from the preform that deviates from the condition management range is discharged as a defect.

Next, after the preform is loaded, at a certain reference time, for example, from the closing timing of the blow cavity mold, the vertical axis driving timing of the stretching rod and its speed pattern, the introduction timing of blow air and its pressure change, etc. Measure process data and obtain blow pattern during blow molding.

Then, the integral value of the primary blow portion of the blow pattern, particularly after the introduction of the primary air until the introduction of the secondary air, and the peak pressure at a predetermined timing after the introduction of the secondary air are calculated, By comparing and comparing this with past data at the time of production of good products, if it deviates from the control range, it is judged that the molded product is defective (defective shape, puncture), for example, if the pressure drops, it is judged as puncture Discharge. At the same time, data is stored as a blow pattern when a defect occurs.

Further, the blow mold temperature is measured at a constant time interval and compared with the data of past production of non-defective products, and if it deviates from the control range, the molded product at that time is defective (volume shrinkage ratio defective). ) And discharge.

In particular, by comparing the change pattern of the blow pressure and the change of the blow mold temperature with the past data and performing statistical processing, the quality of the product is judged at the same time as the blow molding. Transport troubles can be avoided in advance, and not only can a large amount of defects be prevented due to the time lag in the layout up to the inspection device installed in the latter stage, but also the blow blow molding machine can be quickly and reliably treated. You can

Since the stretch blow molding machine having the same structure and mechanism as the conventional one can be used, detailed description thereof will be omitted. Further, as a mechanism (apparatus) for discharging defective molded products, a conventionally used one can be diverted as it is.

[0022]

As described above, according to the present invention,
By determining defective molded products during blow molding and discharging them out of the line, it is possible to avoid transport problems due to defective shapes and reduce the incidence of defective molded products. Can be improved.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating an example of a processing procedure of a monitoring device of the present invention.

FIG. 2 is a block diagram showing a configuration example of a monitoring device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Measuring device, 2 ... Storage means, 3 ... Display means, 4 ... Analysis means, 5 ... Judgment means, 6 ... Ejection mechanism, 11 ... Converter, 1
2, 15 ... Control circuit, 13 ... Ejection device, 14, 16 ... Transmission device, 17 ... Storage device, 18 ... Display device, 19 ... Input means

Claims (3)

[Claims] 1. A stretch blow molding machine monitoring device for heating a preform injection-molded in advance and simultaneously or sequentially performing stretch blow molding to form a hollow body, the measuring device measuring various conditions during blow molding. Device, storage means for storing data from the measuring device, display means for displaying the data, analysis means for analyzing the data, determination means for determining whether the product is acceptable or not based on the analysis result, and defective molded product And a discharge mechanism for discharging the powder to the outside of the line. 2. The stretch blow molding machine monitoring device according to claim 1, wherein one of the condition items measured by the measuring device is blow pressure data which changes with time from a reference time, and the pressure change. A method for monitoring a stretch blow molding machine, which comprises determining the quality of a hollow body product during blow molding by statistically processing a pattern. 3. The stretch blow molding machine monitoring device according to claim 1, wherein one of the condition items measured by the measuring device is blow mold temperature data, and the change is statistically processed. A method for monitoring a stretch blow molding machine, which comprises determining the quality of a hollow body product during blow molding.