JPH11292034A - Inspection method for plastic injection molded products - Google Patents

Abstract

(57) [Problem] To provide a method for inspecting a plastic injection molded article which can reliably detect a defective product without lowering productivity. A method for inspecting a plastic injection molded article, wherein at least one of the last molded plastic injection molded articles among the plastic injection molded articles constituting the same lot is inspected before shipping the plastic injection molded article. Inspection as a molded product, if it is non-defective, all plastic injection molded products that constitute the same lot as the inspected molded product are shipped, and if defective, all plastic injection molded products that constitute the same lot as the inspected molded product are shipped. The plastic injection molded product is put on hold, and all the plastic injection molded products in the held state are inspected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for inspecting a plastic injection-molded article having such a characteristic that when one defective article is generated, the defective article is continuously generated thereafter.

[0002]

2. Description of the Related Art As an example of a conventional method for inspecting a plastic injection molded product, there is a method of inspecting all completed plastic injection molded products, determining whether the product is good or defective, and excluding defective products. In the inspection at this time, a sensor is used,
With this sensor, defective products are detected by detecting scratches, sink marks, etc. on the surface of the plastic injection molded product.

[0003]

However, according to the above-mentioned conventional method for inspecting plastic injection molded articles, all plastic injection molded articles are inspected, so that one plastic injection molded article can be removed in a short time. Inspection needs to be performed, and there is a problem that an inspection apparatus becomes expensive because accuracy is required accordingly. In addition, since the inspection must be completed within a limited time, there is a problem that there is a limitation on the inspection target range, such as inability to inspect details. On the other hand, when the inspection time is lengthened to inspect the details, there is a problem that productivity is reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and can reduce the inspection time and can inspect the details without using an expensive inspection apparatus. It is another object of the present invention to provide a method for inspecting a plastic injection molded product that can be effectively used as a method for reliably detecting a defective product without lowering productivity.

[0005]

SUMMARY OF THE INVENTION A method for inspecting a plastic injection molded article according to the present invention is a method for inspecting a plastic injection molded article. At least one of the plastic injection molded products molded last is inspected as an inspected molded product, and if it is a non-defective product, all the plastic injection molded products constituting the same lot as the inspected molded product are shipped. If it is a non-defective product, the plastic injection molded products constituting the same lot as the inspected molded product are put on hold, and all the plastic injection molded products in this held state are inspected.

In the present invention, the inspection method is not particularly limited. For example, a visual inspection by an inspector or a method using an inspection device using a sensor or the like can be given.

[0007] The timing of the inspection is not particularly limited, but it is more preferable that the inspection be performed, for example, after molding a molded product and before starting a packing operation or a shipping operation.

The interval between the inspections is not particularly limited, but a longer inspection interval is more preferable in the case of a visual inspection because the number of inspections can be reduced.
Further, even when an inspection apparatus is used, the cost for the inspection can be reduced and the inspection can be performed for details, which is more preferable.

The method for holding the plastic injection molded product is not particularly limited.
There is a method using an online system configured by providing terminals such as personal computers on the inspection selection line and the storage line, and connecting the two terminals online. In this method, information on the inspection result of the inspected molded product is transferred from the inspection sorting line to the storage line via two terminals, and if the inspected molded product is defective, the same as the inspected molded product is transferred. The plastic injection molded products are put on hold by stopping the transportation of all the plastic injection molded products constituting the lot to the boxing line.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a method for inspecting a plastic injection molded article according to the present invention will be described with reference to the drawings.

FIG. 1 is a flowchart showing one embodiment of the method for inspecting a plastic injection molded article of the present invention. FIG. 2 is an explanatory diagram schematically showing, for each lot, a plastic injection molded product inspected by the method shown in FIG. FIG. 2A is an explanatory view showing an example of a plastic injection molded product when there is no defective product, and FIG.
It is explanatory drawing which shows an example of a plastic injection molded product when there is a defective product.

FIG. 2 shows, from the left, a previous lot 2 which has already been inspected, a current lot 1 to be inspected from now on, and a next lot 3 to be inspected next to the current lot 1. At least one plastic injection molded product of the last lot 2 which is the last molded product is the inspected molded product 2a of the previous lot 2 (hereinafter, referred to as “pre-tested molded product”) 2a. At least one molded plastic injection molded product is the inspection-executed molded product of the current lot 1
This is referred to as “currently inspected molded article”) 1a. FIG.
Of the current lot 1 and the next lot 3 shown in (b), the shaded portions (the portions indicated by A1 and A2 in the figure)
Is a plurality of defective plastic injection molded products.

In general, when one defective product occurs in a production process of a plastic injection-molded product, the defective product generally occurs continuously thereafter. Therefore, when at least one plastic injection molded product is selected from a large number of plastic injection molded products and inspected as an inspected molded product, if the inspected molded product is a defective product, it is placed before and after the inspected molded product. The plastic injection molded products produced are often defective.

In consideration of this point, the method for inspecting a plastic injection molded article of the present invention comprises the following steps.

First, one or a plurality of plastic injection molded products formed last in the plastic injection molded products constituting the current lot 1 are taken out as inspection-executed molded products 1a (step S1). A visual inspection by an inspector or an inspection using an inspection device is performed on the inspection-executed molded product 1a (step S2). It is determined whether the inspected molded product 1a is a good product or a defective product (Step S)
3).

If the inspected molded product 1a is a non-defective product (see FIG. 2A), plastic injection molded products constituting the same lot as the inspected molded product 1a, that is, all the molded products to be inspected are regarded as non-defective products. The judgment is made and this plastic injection molded product is put into a line for packing and shipping operations (step S6), and the inspection is terminated.

On the other hand, if the inspected molded product 1a is defective (see FIG. 2B), all the inspected molded products are put on hold (step S4). Further, all the molded articles to be inspected are inspected, non-defective products and defective products are selected, defective products are removed (step S5), and only non-defective plastic injection molded products are put into a line for packing and shipping operations. (Step S6), and the inspection ends.

The method of putting the molded article to be inspected on hold is not particularly limited. For example, there is a line (inspection sorting line L4 in FIG. 3 described later) for inspecting the molded article to be inspected, and a method for this inspection. In the meantime, a method of using an online system configured by providing terminals such as personal computers on a line (storage line L3 in FIG. 3 to be described later) for storing molded articles to be inspected and connecting these two terminals online. There is. In this method, information about the inspection result of the inspected molded article is transferred from the line for inspecting the inspected molded article to the line for storing the inspected molded article during the inspection through two terminals, and If the product is defective, the transfer of the molded product to be inspected to the packing line (the boxing line L5 in FIG. 3 described later) is stopped to put the plastic injection molded product on hold.

FIG. 3 is an explanatory view showing an example of an injection molded product manufacturing / shipping line relating to the method for inspecting a plastic injection molded product of the present invention. The injection molded product manufacturing and shipping line includes a manufacturing line L1, a transport line L2, a storage line L3,
It comprises an inspection selection line L4, a box packing line L5, and a shipping line L6.

As shown in FIG. 3, the production line L1 includes an injection molding machine 11 for molding a plastic injection molded product, a container 13 for temporarily storing the plastic injection molded product for transportation, and a production line L1. It comprises a molded product take-out / loading device 12 for taking out a plastic injection molded product and putting it into a container 13 for molding. The transfer line L2 includes a transfer rail 14a and the transfer rail 1
4a that moves along 4a. In the storage line L3, a work container storage automatic warehouse 15 is provided. In the inspection sorting line L4, when the inspected molded product is defective, all the molded products to be inspected are inspected, and the reserved product sorting device 1 for separating the non-defective product from the non-defective product
6 are provided. The box packing line L5 is composed of a cardboard box making machine 17 for making cardboard boxes, and a box packing apparatus 19 for automatically packing plastic injection molded products into cardboard boxes. The shipping line L6 includes a weight check device 20 for checking the weight of the cardboard conveyed by the belt conveyor 22 and the like, and a cardboard sealing machine 21 for sealing the cardboard.

The management and control of each line may be performed by providing a terminal (not shown) for each line and connecting this terminal to one higher-level terminal (not shown). ,
A single terminal (not shown) may manage and control all lines.

Next, an embodiment of the method for inspecting a plastic injection molded article of the present invention using the injection molded article production shipping line shown in FIG. 3 will be described.

(A) First, a plastic injection molded product is molded by the injection molding machine 11 of the production line L1, and the completed plastic injection molded product is taken out of the injection molding machine 11 by the molded product take-out / injection device 12, and the container 13 (Step S1).

(B) When the number of plastic injection-molded articles in the container 13 reaches a predetermined number, the container 13 is moved to the entrance 15a of the in-process container storage automatic warehouse 15 on the storage line L3 by the container transport cart 14b on the transport line L2. Is transported.

(C) The transported container 13 is stored in the automatic warehouse 15 for storing a working container. In a similar manner, the container 13 into which a predetermined number of plastic injection-molded articles are put is transported to the entrance 15a of the in-process container storage automatic warehouse 15 by the container transport cart 14b.
A predetermined number of containers 13 are in-process container storage automatic warehouse 1
Store until it accumulates in 5.

(D) When a predetermined number of containers 13 accumulate in the automatic warehouse 15 for in-process container storage, preparations for boxing plastic injection molded products are started. At the start of this preparation, all the plastic injection molded products stored in the in-process container storage automatic warehouse 15 are
"Plastic injection molded products that make up the same lot." First, the container 13 into which the plastic injection molded product that has been molded last among the plastic injection molded products to be packed in the box is put out from the inspection product outlet 15b and put into the inspection sorting line L4.

(E) Next, one or a plurality of plastic injection-molded products finally molded are taken out of the container 13 delivered from the inspection product delivery port 15b as inspection-executed products, and the quality and the like are inspected (step). S2 and step S3). This inspection may be a visual inspection by an inspector or an inspection using an inspection device (not shown).

(F-1) Inspection execution If the molded product is a good product,
All the molded articles to be inspected are judged to be non-defective, and the container 1 stored in the automatic warehouse 15 for in-process container storage
3 is put into the box packing line L5 (step S6).
At this time, the container 13 taken out for inspection is also put into the boxing line L5. The boxing operation may be a manual operation by the inspector 18 or an automatic boxing operation using the boxing device 19, whereby the plastic injection molded product is boxed into the cardboard box made by the cardboard box making machine 17. . Next, the cardboard box in which the plastic injection-molded products are packed in a box is put into a shipping line L6, subjected to a weight check by the weight check device 20, and sealed by a cardboard box sealing machine 21 before being shipped.

(F-2) On the other hand, if the inspected molded product is defective, all the inspected molded products are inspected for quality and the like. For this purpose, all the containers 13 stored in the in-process container storage automatic warehouse 15 are sequentially conveyed to the reserved product sorting device 16 (step S4), and all the plastic injection molded products put into each container 13 are processed. An inspection is performed, and a good product and a defective product are sorted out (step S5). This inspection may be an inspection using the reserved product selection device 16 or a visual inspection by an inspector. After the inspection, only non-defective plastic injection molded products are put into the container 13 again and put into the box packing line L5 (Step S6). The boxing operation may be a manual operation by the inspector 18 or an automatic boxing operation using the boxing device 19, whereby the plastic injection molded product is boxed into the cardboard box made by the cardboard box making machine 17. . Next, the cardboard box in which the plastic injection-molded products are packed in a box is put into a shipping line L6, subjected to a weight check by the weight check device 20, and sealed by a cardboard box sealing machine 21 before being shipped.

As described above, the plastic injection molded product has the characteristic that if one defective product is generated, the defective product is continuously generated thereafter. What is necessary is just to inspect the molded article to be inspected. Therefore, a defective product can be reliably detected without lowering the productivity.

When a plastic injection molded article of the next lot is produced before the inspection of the molded article of the current lot is completed, as shown in FIG. 2, the molded article 1a of the current lot 1 is inspected. Is defective, the next lot 3 often includes a defective plastic injection molded product (indicated by A2). In this case, it is necessary to inspect all the plastic injection molded products of the next lot 3.

Further, in the above embodiment, when the preparation for packing the plastic injection molded products is started, all the plastic injection molded products stored in the in-process container storage automatic warehouse 15 are referred to as “the same lot. Although it is described as “a plastic injection molded product to be constituted”, the way of dividing a lot is not limited to this. For example, when 1000 plastic injection molded products are sequentially stored in the in-process container storage automatic warehouse 15, these plastic injection molded products are divided into 100 lots to form one lot.
Each time 00 plastic injection molded products are stored in the in-process container storage automatic warehouse 15, the last molded plastic injection molded product may be inspected as an inspection-executed molded product. Further, when there is a change in the type of the plastic injection molded product or a change in the raw material, the above inspection may be performed at that time.

[0033]

As described above, according to the present invention,
Inspection can be performed even for details without shortening the inspection time or using an expensive inspection apparatus. Therefore, it is possible to provide a method for inspecting a plastic injection molded product that can be effectively used as a method for reliably detecting a defective product without reducing productivity.

[Brief description of the drawings]

FIG. 1 is a flowchart showing one embodiment of a method for inspecting a plastic injection molded product of the present invention.

FIG. 2 is an explanatory diagram schematically showing, for each lot, a plastic injection molded product inspected by the method shown in FIG.

FIG. 3 is an explanatory diagram showing an example of an injection molded product manufacturing and shipping line relating to the method for inspecting a plastic injection molded product of the present invention.

[Explanation of symbols]

 1 Current Lot 1a Current Inspection Performed Product 2 Previous Lot 2a Pre-Inspection Performed Product 3rd Lot

Claims (1)

[Claims] 1. A method for inspecting a plastic injection molded product, wherein at least one of the plastic injection molded products formed last in the plastic injection molded products constituting the same lot is shipped before the plastic injection molded products are shipped. Inspections are performed as inspected molded products. If they are good products, all plastic injection molded products that make up the same lot as the inspected molded products are shipped. If they are defective products, all products that make up the same lot as the inspected molded products are shipped. A method for inspecting a plastic injection molded article, wherein the plastic injection molded article is put on hold, and all the plastic injection molded articles in the held state are inspected.