A method for identifying a glass molding machine for a glass container

Abstract

The invention relates to a method for identifying a glass molding machine from a plurality of such machines that enable the forming of a glass melt. The identification method comprises the steps of producing a plurality of glass containers (1), writing a unique identification mark (3) on each produced glass container (1) corresponding to its glass molding machine (4) with an ink readable by a light source (30) having a wavelength outside the visible light spectrum, and reading the written identification mark (3) with a reader (40) to associate the glass container (1 ) with the glass molding machine (4).

Description

[0001] A METHOD FOR IDENTIFYING A GLASS MOLDING MACHINE FOR A GLASS CONTAINER

[0002] TECHNICAL FIELD

[0003] The present invention relates to the inspection of molded containers and, in particular, to a method and system for identifying a molded container, such as a glass bottle or jar, with the respective mold in which it was produced.

[0004] BACKGROUND OF THE INVENTION

[0005] Defects in molded containers, for example, glass bottles and jars, are often associated with defects in the mold from which they were produced. Therefore, in an automated operation where multiple molds are present, it is desirable to have the ability to associate a specific molded container with the mold in which it was produced. This way, the defective mold can be taken out of service for repair, while the other molds can continue production. In cold-end process controls (manual / automatic) of glass housewares, it is not possible to determine the sources of visual defects, i.e., from which mold they originated. Applying a number from the mold onto the product is also not feasible as it would spoil the visual appearance of the product. Quality control merely requests improvement by reporting the defects it detects and their rates. Production spends time identifying the source of the error and the root cause under hot-end conditions based on the feedback received. However, improvement can only be observed after interventions are made following identification. This situation causes an extension in the intervention time for defects and makes it difficult to determine the frequency of defect occurrence, leading to a loss of efficiency.

[0006] US4644151A1 discloses a method and system for identifying a molded container, for instance, a glass bottle, with the mold in which it was produced, and a corresponding container. The publication further discloses that each container includes a series of marks in the form of surface protrusions or embossments arranged at regular intervals around the heel of the container, perpendicular to the container axis. The marks are grouped into pairs of adjacent mark positions, and these groups have two distinct configurations unique to each other. In this way, the entirety of the groups defines a binary code associated with the mold in which the container was produced. The method and system described for reading this code involve directing diffused light energy onto the container heel. This energy is directed at a specific angle to the container axis so that it has an intensity gradient. A camera is positioned to receive the light energy reflected from the heel and is monitored to read the coded marks by tracking the function of the change in the reflection pattern by the protrusions or embossments.

[0007] BRIEF DESCRIPTION OF THE INVENTION

[0008] The object of the invention is to enable the determination of which molding machine is the source of visual defects occurring on glass containers.

[0009] In order to achieve the objective, the invention relates to a method for identifying a glass molding machine from a plurality of such machines that enable the forming of a glass melt. The identification method comprises the steps of producing a plurality of glass containers, writing a unique identification mark on each produced glass container correspondingto the glass molding machine with an ink readable by a light source having a wavelength outside the visible light spectrum, and reading the written identification mark by a reader to associate the glass container with the glass molding machine. In this way, the identification method allows for the determination of which mold produced a glass container found to be defective, both in automatic inspection machines and in manual quality controls, and the identification marks corresponding to this mold can be tracked in the production tracking system. Thus, instead of stopping the entire production line, only the defective molding machine can be stopped to correct the fault.

[0010] In a preferred embodiment of the invention, the unique identification mark of the glass molding machine is written by an inkjet printer. This enables the identification marks to be written on the glass containers with high precision and speed. Thus, rapid detection of faults is ensured. In a preferred embodiment of the invention, the unique identification mark of the glass molding machine is written by the inkjet printer with the aid of a guide system (traversing system) that moves longitudinally. The use of a guide system ensures that the inkjet printer moves precisely and accurately over the glass container. This ensures that the identification marks are placed consistently and evenly on each glass container, enabling more effective quality control in the production process.

[0011] In a preferred embodiment of the invention, the identification mark is written on the glass container by the inkjet printer at the exit of a cooling unit. This ensures better adhesion and permanence of the ink marking on the glass container. Thus, quality control processes can be performed quickly.

[0012] In a preferred embodiment of the invention, the identification mark is an alphanumeric mark. This allows the identification marks on the glass containerto be read by a machine or an operator, ensuring an improvement in the quality control process.

[0013] In a preferred embodiment of the invention, the identification mark on the glass container is read by a camera. This enables the implementation of automatic monitoring and control operations on the production line. Reading with a camera minimizes human error and provides the capability for rapid data collection.

[0014] In a preferred embodiment of the invention, the identification mark on the glass container is read by the camera under ultraviolet light. This allows the identification marks to be made using ink invisible to the naked eye and to be visible only under special light. Thus, it does not affect the visual appearance in cases where visible markings on the glass container are not desired.

[0015] In a preferred embodiment of the invention, defects on the glass container are detected by a quality control apparatus, and the mold identification mark of the glass containers where a defect is detected is identified. The identification of mold marks on defective glass containers allows for rapid intervention directed at the source of the problem by determining which mold the faulty products originated from. This method accelerates the process of segregating faulty products on the production line and taking the necessary corrective actions. Thus, an increase in overall production quality is achieved.

[0016] BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic representation of the line where the identification marks of the glass containers subject to the invention are written.

[0018] Figure 2 is a schematic representation of the line where the identification marks of the glass containers subject to the invention are read.

[0019] DETAILED DESCRIPTION OF THE INVENTION

[0020] In this detailed description, the development subject to the invention is described with references to examples for the sole purpose of better illustrating the subject matter, without any intention of limitation.

[0021] Figure 1 schematically shows the production line where identification marks are written on the glass containers of the invention. A plurality of glass containers (1 ) are formed from a glass molding machine (4) according to their intended use and are conveyed on a conveyor belt (2). The glass containers (1) can be defined as, but not limited to, glass goblets, glass housewares, or bottles. The glass containers (1 ) exiting the glass molding machine (4) are conveyed by the conveyor belt (2) and loaded sequentially into a cooling unit (lehr) (6). The number of rows loaded may vary depending on parameters such as product dimensions, cooling furnace belt speed, and production machine speed. For example, for a glass goblet, the stem forming machine consists of 28 stations, the body forming machine of 12 stations, the rim cutting machine of 15 stations, and the bodystem joining machine of 60 stations. For other products in the glass housewares group, the forming machines on different production lines in the factory have production stations with physically different numbers of glass molding molds depending on the type and size of the product being manufactured. The identification mark (3) printed on the base of the glass products with invisible ink can be used as an alphanumeric mark and may consist of 2-digit numbers representing each station on the forming machine. The glass containers (1 ) exiting the cooling unit (6) are conveyed by the conveyor belt (2), and an identification mark (3) is written on a base part of the glass containers (1 ) by an inkjet printer (10) with an ink readable by a light source having a wavelength outside the visible light spectrum. The identification mark (3) written on the glass container (1 ) is applied by a biaxial guide system (20) extending along the length of the conveyor belt (2). With the help of a PLC program, settings such as the number of rows of products loaded into the cooling unit (6) and the printer head speed value can be configured for the printer (10), allowingthe mold / section numberto be written on the base of the glass containers (1 ) on the line. Defects on the glass container (1 ) are detected by a quality control apparatus (5). The quality control apparatus (5) includes multiple sensors and cameras. The mold identification mark (3) of the glass containers (1 ) where a defect is detected is identified. This allows for rapid intervention directed at the source of the problem by identifying the glass mold machine (4) from which the defective products originated by detecting the mold identification marks (3) of the defective glass containers (1).

[0022] Figure 2 schematically shows the line where the identification marks of the glass containers subject to the invention are read. The identification mark (3) written on the base part of the glass container (1 ) can be illuminated with ultraviolet light by a light source (30) and read by an operator or a reader (40) to determine in which glass molding machine (4) it was formed. The identification mark (3) can be used as an alphanumeric mark. 2-digit numbers, 6-digit numbers, or 8-digit numbers are used as alphanumeric marks. The reader (40), particularly a camera, can detect the defective glass containers (1 ) on the conveyor belt (2), and thanks to the unique identification mark (3) of the glass mold machine (4), it can be determined in which glass molding machine (4) it was formed. In an exemplary identification method, the glass container (1) is selected as a stemmed glass, a goblet. The goblet takes its final form through a total of four forming machines. The four forming machines are named as the body forming machine, stem forming machine, rim cutting machine, and body & stem joining machine. The number of stations (sections) for each of these machines is different. At the exit of the cooling unit (6), an inkjet printer (10), which operates with ink visible only under UV light, is installed on the line together with a guide system (20) that moves in 2 axes. With the help of a PLC program, settings such as the number of rows in which the glass containers (1 ) are loaded into the cooling unit (6) and the printer head speed value can be configured for the inkjet printer (10), allowing two digits representing the section number where they were processed in each glass molding machine (4) to be written on the base parts of the glass containers (1 ) on the line. The base of the final product will have a 6 or 8-digit number. The reader (40), preferably a camera that inspects the goblets using digital image processing techniques, will be able to read the number located on the base part of the glass container (1 ) with UV light sources (30). When the 6 / 8-digit code read by the inspection machine is decoded by the software, it will be possible to determine in which section of which glass molding machine (4) the defect was produced. These statistical displays can be read by an operator.

[0023] REFERENCE NUMERALS

[0024] 1 Glass Container

[0025] 2 Conveyor Belt

[0026] 3 Identification Mark

[0027] 4 Glass Molding Machine

[0028] 5 Quality Control Apparatus

[0029] 6 Cooling Unit (Lehr)

[0030] 10 Inkjet Printer

[0031] 20 Guide System

[0032] 30 Light Source

[0033] 40 Reader

Claims

CLAIMS1. A method for identifying a glass molding machine from a plurality of such machines that forms a glass melt comprising the steps of manufacturing a plurality of glass containers (1 ); writing a unique identification mark (3) to each glass container (1 ) corresponding to its glass molding machine (4) on the produced glass container (1 ) with an ink readable by a light source (30) having a wavelength outside the visible light spectrum; reading the written identification mark (3) with a reader (40) to associate the glass container (1 ) with glass molding machine (4).

2. A method according to claim 1 , wherein the unique identification mark (3) of the glass molding machine (4) is written by an inkjet printer (10).

3. A method according to claim 2, wherein the unique identification mark (3) of the glass molding machine (4) is written by the inkjet printer (10) by means of a guide system (20) that moves longitudinally.

4. A method according to any of the preceding claims, wherein the identification mark (3) is written on the glass container (1 ) by the inkjet printer (10) at the outlet of a cooling unit (6).

5. A method according to any of the preceding claims, wherein the identification mark (3) is an alphanumeric mark.

6. A method according to any of the preceding claims, comprising the step of reading the identification mark (3) located on the glass container (1 ) by a camera.

7. A method according to claim 6, wherein the identification mark (3) on the glass container (1) is read by the camera under ultraviolet light.

8. A method according to any of the preceding claims, comprising the step of detecting defects on the glass container (1 ) by a quality control apparatus (5), and identifying the identification mark (3) of the glass containers (1 ) on which a defect has been detected.

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