EP0678892A2 - Method and arrangement for determining measurement accuracy and for documenting quality control in the manufacture of luminous tubes - Google Patents

Abstract

The system uses a data collection system (6) for the mfg parameters, eg the temp pressure, heating current and duration, of the mfg process, supplied via respective sensors (4). The data is transferred to a programme-controlled electronic processor (3), used for process control via adjustable setting elements (5). Some or all of the process data provided by the data collection system is indicated on a display monitor (19) and handled by a data memory (11), for entering in a digital archive memory (14) and/or for providing a hard-copy print-out. <IMAGE>

Description

The invention relates to a method for verifying the measurement accuracy of the manufacturing process and for documentation for quality assurance in the manufacture of fluorescent tube systems by means of a vacuum pump system and a filling gas dosing system and a high-voltage part for ignition and heating of the fluorescent tubes.

The manufacture of fluorescent tube systems and their quality and service life depend crucially on the pressure and the purity of the filling gases. If the fluorescent tube has not been filled with an optimal pressure determined from experience, the service life can decrease considerably. The pump and bakeout components in the manufacturing process of fluorescent tube systems have also emerged as factors influencing the service life. After all, the quality of fluorescent tubes largely depends on the craftsmanship and knowledge as well as the care of the specialists who manufacture the fluorescent tubes. But even with careful observance of work instructions and empirical values, so-called inexplicable failures can occur in the event of undetected measurement errors. In order to be able to counteract this, the quality assurance standards of ISO 9000-9004 lend themselves, when used the manufacturer and the user are guaranteed a corresponding quality. However, the implementation of ISO 9000-9004 requires that the relevant manufacturing parameters can be measured and checked.

So far, no measurable and controllable manufacturing process for fluorescent tube systems according to the quality assurance standards ISO 9000-9004 is known.

The invention is therefore based on the object of providing a method and an arrangement for detecting and documenting the measurement accuracy of the production sequence in the manufacture of fluorescent tube systems, in which it is ensured that even previously undetected measurement errors can be made recognizable and recordable.

Another task is to make these production processes certifiable according to ISO 9000-9004.

• a) die relevanten Fertigungsparameter, wie Drücke, Temperaturen, Ausheizströme und -zeiten des Fertigungsprozesses 1 von einem Datenerfassungssystem 6 mit spezifischer Sensorik 4 erfaßt und einer programmgesteuerten elektronischen Datenverarbeitung 3 zugeführt werden, wobei diese mit einem Meß- und Steuerprogramm ausgestattet ist, in das die in einem vorgegebenen, normgerechten Bereich liegenden Fertigungsparameter eingespeichert sind, welche über die Prozeßsteuerung 7 mittels der Stellglieder 5 den Fertigungsprozeß 1 beeinflussen, und
• b) ein mehr oder minder großer Teil der von der Sensorik 4 erfaßten Meß- und Prozeßdaten von der Datenverarbeitung 3 auf einem Bildschirm 19 angezeigt und programmgemäß in einem Daten-Speicher 11 protokolliert und in einem digitalen Daten-Archiv 14 und/oder in einer gedruckten Akte 12/13 dokumentiert werden.

This object is achieved in that

• a) the relevant manufacturing parameters, such as pressures, temperatures, heating currents and times of the manufacturing process 1 detected by a data acquisition system 6 with specific sensors 4 and supplied to a program-controlled electronic data processing 3, which is equipped with a measurement and control program in which the Production parameters lying in a predetermined, standard-compliant range are stored, which influence the production process 1 via the process control 7 by means of the actuators 5, and
• b) a more or less large part of the measurement and process data recorded by the sensor system 4 is displayed by the data processing 3 on a screen 19 and, according to the program, is logged in a data memory 11 and in a digital data archive 14 and / or in a printed one Files 12/13 are documented.

Advantageous further developments are characterized in the dependent claims.

An embodiment of the invention is shown in the drawing and will be described in more detail below.

Fig. 1

ein Funktionsdiagramm der Erfindung, in welchem die Wechselwirkungsmöglichkeiten zwischen der Prozeß-Steuerung für die Herstellung von Leuchtröhren, dem Bearbeiter und dem erfindungsgemäßen rechnergestützten Meß-, Steuer- und Protokollsystem veranschaulicht sind,

Fig. 2

ein Blockschaltbild einer für die Herstellung von beispielsweise zwei Leuchtröhren zusammenwirkenden Vakuum-Pumpanlage und einer Füllgas-Dosieranlage eines erfindungsgemäßen Pumpstandes,

Fig. 3

ein Funktionsdiagramm für die Vakuum-Pumpanlage und der Füllgas-Dosieranlage nach Fig. 1, in dem die Wechselwirkungsmöglichkeiten zwischen der Prozeß-Steuerung, dem Bearbeiter, der Daten-Erfassung, den Pump- und Füllkomponenten und den zugeordneten Meßsensoren sowie den Stellgliedern dargestellt sind,

Fig. 4

ein Funktionsdiagramm der Hochspannungsversorgung nach Fig. 1, in dem die Wechselwirkungsmöglichkeiten zwischen der Prozeß-Steuerung, dem Bearbeiter, der Datenerfassung, den Hochspannungs- und Stromversorgungskomponenten, den zugeordneten Meßsensoren und Regelelementen sowie den Sicherheitsschaltungen dargestellt sind,

Fig. 5

ein Blockschaltbild der Ausheizanlage nach Fig 4,

Fig. 6

ein Funktionsdiagramm der Sensorik nach Fig. 1, in dem die Wechselwirkungsmöglichkeiten zwischen dem Fertigungsprozeß, dem Bearbeiter und der Sensorik mit den Stellgliedern sowie der Datenerfassung dargestellt sind,

Fig. 7

ein Funktionsdiagramm der Stellglieder nach Fig. 1, in dem die Wechselwirkungsmöglichkeiten zwischen dem Fertigungs-Prozeß, dem Bearbeiter und den Stellgliedern sowie der Datenerfassung mit der Sensorik dargestellt sind und

Fig. 8

ein Funktionsdiagramm der programmgesteuerten elektronischen Datenverarbeitung der Erfindung nach Fig. 1, in dem die Wechselwirkungsmöglichkeiten zwischen der Datenerfassung, dem Bearbeiter und der Prozeßsteuerung sowie der programmgesteuerten elektronischen Datenverarbeitung veranschaulicht sind.

Show it

Fig. 1

1 shows a functional diagram of the invention, in which the interaction possibilities between the process control for the production of fluorescent tubes, the processor and the computer-aided measuring, control and protocol system according to the invention are illustrated,

Fig. 2

2 shows a block diagram of a vacuum pump system which interacts for the production of, for example, two fluorescent tubes and a filling gas metering system of a pumping station according to the invention,

Fig. 3

1, in which the interaction possibilities between the process control, the processor, the data acquisition, the pump and filling components and the associated measuring sensors and the actuators are shown,

Fig. 4

1, in which the interaction options between the process control, the processor, the data acquisition, the high voltage and power supply components, the associated measuring sensors and control elements and the safety circuits are shown,

Fig. 5

3 shows a block diagram of the heating system according to FIG. 4,

Fig. 6

1, in which the interaction options between the manufacturing process, the processor and the sensor system with the actuators and the data acquisition are shown,

Fig. 7

a functional diagram of the actuators of FIG. 1, in which the interaction possibilities between the manufacturing process, the processor and the actuators and the data acquisition with the sensor system are shown and

Fig. 8

a functional diagram of the program-controlled electronic data processing of the invention according to FIG. 1, in which the interaction options between the data acquisition, the processor and the process control and the program-controlled electronic data processing are illustrated.

Fig. 1 shows a schematic functional diagram of the invention, in which the variable division of tasks in the manufacturing process 1 for the manufacture of fluorescent tube systems between the processor 2 and a program-controlled electronic data processing 3 is shown. Variable division of tasks insofar as the processor 2 with an area P as a process area, an area V in which a sensor system 4, actuators 5, a data acquisition 6 and a process controller 7 are arranged, and an area D which is essentially program-controlled includes electronic data processing 3 with their peripheral devices, must interact mutually. From this it is clear that the processor 2 can observe and assess the process area P, while in the area V a more or less large part of the sensors 4 and the actuators 5 via the data acquisition 6 or via the process control 7 interact with the program-controlled electronic data processing 3, and are controlled on the one hand by software and on the other hand by inputs on a keyboard 8 by the processor 2.

The data processing software 3 includes the programs with the relevant manufacturing parameters for the manufacture of fluorescent tubes 9 and the data for control and monitoring as well as for documentation of the manufacturing process as evidence of a quality control, preferably according to ISO standards 9000-9004 and / or The manufacturing recommendations based on the experience of the specialist, for example those of the Fachverband Lichtwerbung eV This is the only way to demonstrate compliance with the manufacturing instructions in connection with data processing 3 or to identify the cause of a quality defect in the fluorescent tubes.

Relevant data for the production of fluorescent tubes 9 are therefore their data with regard to the pumping time, the pressure profiles, the final pressures, the heating-up time and temperature and their filling components, which significantly influence the service life of the fluorescent tubes.

As can further be seen from FIG. 1, a more or less large part of the measurement and process data recorded by the sensor system 4 can also be displayed by the data processor 3 to the processor 2 on a screen 10 and, according to the program, logged in a data memory 11 and for example are documented in accordance with ISO standards 9000-9004 by means of a printer 12 in a file 13 and / or directly in a digital data archive 14.

The part of the sensor system 4 and the actuators 5 that is not connected to the data processing 3 is operated and observed manually by the processor 2. Here, the part of the data that is relevant for the documentation, for example in accordance with ISO standards 9000-9004, is requested by data processing 3 via screen 10, and then entered by processor 2 via keyboard 8. These values are then, appropriately identified, logged in the data memory 11 and documented in the data archive 14 and / or in the file 13.

The functions identified by double arrows in the documentation area D are indispensable according to the invention, for example in order to meet the ISO standards 9000-9004 in the proposed system according to FIG. 1. The functions and components of the data archive 14 can be integrated or retrofitted, depending on the existing system or stage of expansion.

FIG. 2 shows a block diagram of the pumping station for the production of, for example, two fluorescent tubes 9, specifically the interaction of a vacuum pump system 15 with a filling gas metering system 16.

The vacuum pump system 15 essentially comprises a pre-pump 17 which is connected to a main pump 19 via a corrugated hose 18. An exhaust filter 20 is connected upstream of the pre-pump 17. The pre-pump 17 is, for example, a 2-stage rotary vane pump, while the main pump 19 is, for example, a turbo-molecular pump. A pre-vacuum indicator 21 assigned to the pre-pump 17 and a main vacuum indicator 22 assigned to the main pump 19 are each coupled to the data processing 3 according to FIG. 1 via the sensors 4 and the data acquisition 6, and the pressure components thereof measured and monitored.

The process control 7 guided by the data processing 3 according to FIG. 1 actuates not only the remote-controlled valves via the suitable actuators 5, but also the pre-pump 17 and the main pump 19, which optionally also in combination with a bypass arranged corner valve 23 can be done. An electromagnetically actuated corner valve 25 with a variable conductance, which is equipped with an additional servo motor 24 and is advantageously essential to the invention, which advantageously enables sensitive regulation of the gas pressure in the fluorescent tubes 9 during the required heating-up phases. Between the corner valve 25 and the main pump 19, a flood valve 26 is connected, which is assigned to the main pump.

The pumping station has a left and a right worktop Al, Ar and is each provided with a connection 27 for the pump stems of the fluorescent tubes 9. The inactive worktops are separated from the pumping station by shut-off valve 57. The pump stems are connected vacuum-tight to a glass rake, i. H. melted. Hand-operated valves 28 each serve to blow the electrode pump stems of the fluorescent tubes 9 onto the glass rakes for the left or right worktop shown). These plug-in connections consist of a combination of solid and soft components and automatically pull tight during the pumping process due to the pressure difference.

Further worktops can advantageously be arranged. Furthermore, more than one fluorescent tube 9 can be connected to the worktops Ar, Al.

A safety valve 32 in the vacuum pump system 15 serves to protect against excess pressure in the pump lines and in the fluorescent tubes in the event of a breakdown of the control valve 29 in the filling gas metering system 16 or the connection valves 30.

In the filling gas metering system 16, filling gas pressure cans 33 with a neon / argon mixture are provided, each of which is provided with a pressure manometer 31, these being evaluated directly by the processor 2.

The connection valves 30 can advantageously be replaced by electromagnetic valves (not shown in the block diagram) and used in conjunction with the electromagnetically controlled control valve 29 for the metered filling of the connected fluorescent tubes 9. 37 designates a filling manometer, which interacts with the control valve 29 and is evaluated directly by the processor 2.

As a special precaution to prevent the plasma from igniting in the direction of the pumping station, a catcher valve 34 with a sintered filter 35 is advantageously installed in front of each worktop as a breakdown protection.

Fig. 3 shows the functional diagram of the interaction between the processor 2, the measurement, control and data acquisition area V and the vacuum pump system 15 and the filling gas metering system 16. It provides a scheme for operating and controlling the vacuum pump and Filling gas metering system and the pressure measuring components. The horizontal arrows B indicate the control and display elements which are operated and evaluated directly by the processor 2, while the arrows F proceeding from the actuators 5 to the pre-pump 17, main pump 19 and to the corner valve 25, which represent vacuum control by the actuators. The arrows G emanating from the actuators 5 show the control of the filling gas metering system 16, namely the control valve 29 and the advantageously electromagnetically actuated valves 30a. The arrows E go from the preliminary and main vacuum indicators 21, 22 to the sensor system 4 and show the pressure measurement of the vacuum pump system 15 by the sensor system 4. The feedback from the servomotor 24 to the sensor system 4 is shown by the arrow R. The functional diagram thus shows the interaction options between the process controller 7, the processor 2, the data acquisition 6, the pumping and filling components and the associated measuring sensors 4 and the actuators 5.

in der Spannungs- und Stromüberwachung 38 mit einer geeigneten Thyristorschaltung. Eine Zündspannungsvorgabe kann außer durch eine geeignete Wahl des Umspannungsverhältnisses an einem Hochspannungstransformator 41 (vgl. Fig. 5) auch durch andere elektrische Maßnahmen sichergestellt werden.FIG. 4 shows the functional diagram for operating and controlling the high voltage and power supply for the heating system of the measuring and control and documentation system according to the invention for the pumping station. A voltage and current monitor 38, a remote temperature monitor 39 and a catcher circuit 40 are provided in cooperation with the sensor system 4. While the measured values are fed to the data acquisition 6 via the sensor system 4, the working current is limited $\text{I (= I₁ = I₂)}$

in the voltage and current monitoring 38 with a suitable thyristor circuit. An ignition voltage specification can be ensured not only by a suitable choice of the transformation ratio on a high-voltage transformer 41 (cf. FIG. 5) but also by other electrical measures.

The voltage and current monitor 38 contains a high-resistance voltage divider circuit 48 for measuring the reference voltages U 1 and U 2. The remote temperature monitoring 39 of the glass temperature T₁ (l) and T₂ (l) or T₁ (r) and T₂ (r) is essential to the invention and advantageously by means of an infrared measurement, and the temperature of the red-hot electrodes of the fluorescent tubes 9 is determined according to the invention by measuring the intensity of a filtered area of the light emission. In order to meet the required safety requirements when high voltage is present, the information is transmitted via light guides 43, for example by means of light emitting and photo diodes.

The horizontal arrows B indicate the circuit elements of the high voltage and power supply in the heating system, which are operated and evaluated directly by the processor 2.

bei ${\text{U}}_{\text{s}}\text{=F(U₁+U₂)}$

. U_s ist die Zündspannungvorgabe. Weiterhin sind im Blockschaltbild nach Fig. 5 bezeichnet mit: 49 ein Stellpotentiometer für die Fängerspannung U_f, 50 eine Gleichspannungsversorgung für den Fängerstrom I_f, 51 ein Schlüsselschalter, 52 eine AC-Stromversorgung für die Meßgeräte der Vakuum-Pumpanlage 15 und der Füllgas-Dosieranlage 16, der Datenverarbeitung 3 und der Vor- und Haupt-Pumpe 17 und 19, 53 weitere Relaisschalter, 54 eine Leistungs- bzw. Strombegrenzung und Zündspannungbereichsumschaltung, 55 ein Schutz-Kontakt-Umschalter, 56 ein Hochspannungsumschalter, 57 eine Anzahl Temperatursensoren an den Leuchtröhren 9 auf der rechten bzw. der linken Arbeitsplatte Ar, Al.The heating system is shown as a block diagram in FIG. 5 and essentially contains the high-voltage supply with controllable current I, safety circuits and high-voltage measuring units and control elements. With 44 and 45, the catcher electrode for the left and the right worktop for the manufacture of the fluorescent tubes 9 is designated, which interact with the catcher valves 34 (see FIG. 2). The occurrence of a catcher current I _f with a catcher voltage U _{f present} in the catcher circuit 40 (cf. FIG. 4) leads to a shutdown of the high voltage via a safety contactor 46 as well as the opening of activated protective contacts 47. see FIG. 4) is only permitted in the de-energized state of the primary circuit of the high-voltage transformer 41. The double connection of the measuring resistors R _m in the voltage divider circuit 48 also increases the circuit reliability. The factor F is calculated as the voltage division ${\text{F = 2RM / R}}_{\text{m}}$

at ${\text{U}}_{\text{s}}\text{= F (U₁ + U₂)}$

. U _s is the ignition voltage specification. Furthermore, in the block diagram according to FIG. 5, 49 denotes a control potentiometer for the catch voltage U _f , 50 a DC voltage supply for the Catcher current I _f , 51 a key switch, 52 an AC power supply for the measuring devices of the vacuum pump system 15 and the filling gas dosing system 16, the data processing 3 and the pre-and main pump 17 and 19, 53 further relay switches, 54 a power - or current limitation and ignition voltage range switchover, 55 a protective contact switch, 56 a high-voltage switch, 57 a number of temperature sensors on the fluorescent tubes 9 on the right or left worktop Ar, Al.

The inventive grounding of the electrodes of the fluorescent tubes 9 near the pump advantageously ensures that the ignition of a gas discharge in the pump lines, as was previously possible with one, with more than two or with fluorescent tubes with very different lengths, is now avoided in normal operation. In the event of an air break-in, separate provision is made by the catcher valves 34.

If necessary, this grounding can also be replaced by a conventional center grounding of the high-voltage winding of the transformer 41.

6 shows the functional diagram according to the preceding FIGS. 3 and 4 and illustrates in a summarized form the sensory part of the pumping station according to the invention with the pumping and filling gas dosing system 15, 16 and the heating system, specifically by means of the sensor system 4.

FIG. 7 shows the functional diagram according to FIGS. 3 and 4 and illustrates in a summarized form the controlling part of the pumping station by means of the actuators 5.

FIG. 8 shows a functional diagram according to FIG. 1 of the system overview, namely a further exemplary embodiment of the documenting area D. The in the figure The specified AD / DA converter with relay cards can be connected and controlled in a wide variety of ways.

Claims (10)

Process for verifying the measuring accuracy of the manufacturing process (1) and for documentation for quality assurance in the manufacture of fluorescent tube systems using a vacuum pump system (15) and a filling gas dosing system (16) as well as a high-voltage part for ignition and heating of the fluorescent tubes (9), characterized in that a) the relevant manufacturing parameters, such as pressures, temperatures, heating currents and times of the manufacturing process (1) are recorded by a data acquisition system (6) with specific sensors (4) and fed to program-controlled electronic data processing (3), these being and control program is equipped, in which the manufacturing parameters lying in a predetermined, norm-compliant range are stored, which influence the manufacturing process (1) via the process control (7) by means of the actuators (5), and b) a more or less large part of the measurement and process data recorded by the sensor system (4) is displayed by the data processing system (3) on a screen (19) and, according to the program, logged in a data memory (11) and in a digital data Archives (14) and / or documented in a printed file (12/13). Method according to Claim 1, characterized in that a part of the sensor system (4) and the actuators (5) which is not connected to the data processing (3) is operated manually by a processor (2), if necessary and is observed, the part of the data which is relevant for the documentation being requested by the data processing unit (3) via the screen (10) and entered and logged by the processor (2) via a keyboard (8) in the data memory (11). Method according to Claim 1, characterized in that the program-controlled electronic data processing (3) detects several measured variables almost synchronously via the sensor system (4) and the actuators (5) are controlled accordingly. Method according to claim 1, characterized in that remote monitoring (39) of the glass temperature is carried out by means of an infrared measurement and that the temperature of the red-hot electrodes of the fluorescent tubes (9) is determined by measuring the intensity of a filtered area of the light emission. Arrangement for carrying out the method according to claim 1, characterized in that in the vacuum pump system (15) an electromagnetic angle valve (25) equipped with a servomotor (24) with variable conductance is provided, and thus the control of the pump power and the pressure is also made possible during the heating-up periods. Arrangement for performing the method according to claim 1, characterized in that for the vacuum-tight connection of the pump stem of the fluorescent tubes (9) to the pump system, instead of a glass rake, a plug-in connection is provided, which consists of a combination consists of solid and soft components, which pull themselves tightly by means of the pressure difference during the pumping process. Arrangement for performing the method according to claim 1, characterized in that the switching and metering valves of the vacuum pump system (15) and / or the filling gas metering system (16) are electromagnetically controlled valves. Arrangement for carrying out the method according to claim 1, characterized in that a catcher valve (34) with a sintered filter (35) is provided as a breakdown protection to prevent the plasma from igniting. Arrangement for carrying out the method according to claim 1, characterized in that the electrodes of the fluorescent tubes (9) close to the pump have an earth connection. Arrangement for carrying out the method according to claim 1, characterized in that light guides (43) are provided for the information transmission to and from the temperature measuring units.

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