JP7534952B2 - Method for acquiring data on energizing conditions in electrocoating equipment, electrocoating equipment - Google Patents

Description

The present invention relates to a method for acquiring data on current flow conditions in an electrocoating equipment in which current is applied to multiple vehicle bodies in an electrocoating tank from multiple electrodes arranged in the electrocoating tank, and to the electrocoating equipment.

Conventionally, there has been known an electrodeposition coating system that applies an electric current from multiple electrodes arranged in an electrodeposition tank to a vehicle body immersed in an electrodeposition paint in the electrodeposition tank, thereby performing electrodeposition coating on the vehicle body (see, for example, Patent Document 1). Electrodeposition coating using such electrodeposition coating systems is widely used in the base coating process of vehicle bodies for the purpose of imparting rust prevention performance. However, in electrodeposition coating, excessive voltage is applied to ensure the film thickness of the interior panel of the vehicle body, which results in energy and paint losses and excess film thickness. For this reason, various methods have been devised to adjust the thickness of the paint film formed on the surface of the vehicle body to a targeted range.

For example, as shown in FIG. 5, first, the current value applied from the electrode 102 placed in the electrodeposition tank 101 to the vehicle body 103 in the electrodeposition tank 101 is calculated (offline) based on the design information of the equipment, rather than actually measuring on the production line. The current value is calculated based on the time when the vehicle body 103 passes the electrode 102 and the voltage value. Next, the calculated current value is compared with the film thickness measured using a film thickness meter (not shown). Then, by adjusting the voltage value applied to the electrode 102 based on the comparison result, the coating film can be brought closer to the targeted thickness range. It is generally known that the film thickness tends to increase as the voltage value increases.

JP 2020-132903 A (FIGS. 1, 4, etc.)

However, even if the current value of the current applied to the vehicle body 103 is calculated based on the design information of the equipment, there is a problem in that it is not possible to accurately determine how much current is actually applied to the vehicle body 103. Even if an ammeter is connected to all electrodes 102 and the current applied to the vehicle body 103 from a specific electrode 102 is actually measured (in-line), there is a high possibility that the current application range 105, which is the range in which the current is expected to be applied, will deviate from the actual current application range 106 (see Figure 6). In this case, since the current value cannot be measured accurately, there is a problem in that the coating film formed on the surface of the vehicle body 103 cannot be made to the desired thickness range even if the voltage value is adjusted based on the result of comparing the current value and the film thickness.

The present invention was made in consideration of the above problems, and its purpose is to provide a method for acquiring current condition data in an electrodeposition coating equipment, and an electrodeposition coating equipment, which can accurately measure the current applied to the vehicle body, thereby allowing the coating film formed on the surface of the vehicle body to have a targeted thickness range.

In order to solve the above problem, the invention described in claim 1 is a method for acquiring data on current flow conditions based on measurement results when current is applied from multiple electrodes arranged in an electrodeposition tank to multiple vehicle bodies in the electrodeposition tank that are continuously transported by a transport means, the method comprising: an electrode selection step for selecting a specific electrode from the multiple electrodes; a current application range definition step for defining a current application range, which is a positional range in which a current is expected to be applied to the vehicle body from the specific electrode when the vehicle body is transported along the transport direction, based on shape information of the vehicle body and design information of the equipment; and a forward current application range definition step for determining the current application range, which is a positional range in which a current is expected to be applied to the vehicle body from the specific electrode when the vehicle body is transported along the transport direction, based on shape information of the vehicle body and design information of the equipment while transporting the vehicle body, according to the moving position of the vehicle body. The gist of the method for acquiring current condition data in an electrodeposition coating facility is to carry out a current measurement step of actually measuring the current applied to the vehicle body from the specific electrode, a comparison and calculation step of comparing the center position of the current application range with the peak position of the measured current and calculating the amount of deviation of the peak position from the center position, a current application range redefinition step of offsetting the center position to coincide with the peak position based on the amount of deviation and redefining the current application range, and a current application range application step of applying the redefined current application range to the remaining electrodes of the plurality of electrodes excluding the specific electrode.

In the invention described in claim 1, the current applied to the vehicle body from a specific electrode is actually measured in the current measurement step, so that the current value of the current applied to the vehicle body can be accurately known. Moreover, in the comparison calculation step, the amount of deviation of the peak position of the measured current from the center position of the current application range is calculated, and in the current application range redefinition step, the center position is offset to coincide with the peak position to redefine the current application range. As a result, the deviation between the redefined current application range and the actual current application range is reduced, so that an accurate current value can be obtained by measuring the current in the redefined current application range. Therefore, based on the obtained current value (measurement result), accurate data regarding the current application conditions, specifically, data showing the relationship between the current value and the film thickness, can be obtained. Therefore, by adjusting the voltage value applied to the vehicle body based on the obtained data, the paint film formed on the surface of the vehicle body can be set to a targeted thickness range, improving the paint quality of the vehicle body.

Note that a large number of electrodes (approximately 100 to 160) are usually placed in an electrodeposition tank. For this reason, it is not realistic to precisely define the current application range for each electrode, as this requires a great deal of effort. Therefore, in claim 1, a current application range application step is performed, and the redefined current application range is applied to the remaining electrodes excluding the specific electrode. In this way, even if a large number of electrodes are placed in the electrodeposition tank, the current application range can be easily defined for all electrodes.

The invention described in claim 2 is based on claim 1, and the conveying means includes a rail and a plurality of hanger rails that are attached to the rails and that suspend and convey the vehicle body, and each of the hanger rails is provided with a pulse generator that periodically transmits a pulse signal, and the distance traveled from a reference position of the vehicle body suspended on the hanger rail is calculated based on the number of pulse signals transmitted from the pulse generator.

According to the invention described in claim 2, the moving distance of the vehicle body from the reference position is calculated based on the number of pulse signals transmitted from the pulse transmitter. Therefore, the vehicle body whose calculated moving distance and the distance from the reference position to the specific electrode are closest can be selected as the vehicle body to which current is applied from the specific electrode. In addition, because a pulse transmitter is used, the moving distance can be calculated more easily than when a sensor, camera, etc. are used.

The invention described in claim 3 is based on claim 1 or 2 and further includes an integrated current value calculation step of calculating an integrated current value, which is the amount of current applied per unit time, by measuring the current in the redefined current application range.

According to the invention described in claim 3, the integrated current value, i.e., the amount of electricity (coulomb amount), is calculated in the integrated current value calculation step. In this case, the film thickness can be predicted using the integrated current value, so the film thickness can be adjusted more accurately than when the film thickness is predicted simply using the current value.

The invention described in claim 4 is an electrocoating equipment including an electrocoating tank that stores electrocoating paint and transports a vehicle body while immersed in the electrocoating paint, a plurality of electrodes that are arranged in the electrocoating tank and spaced apart along the transport direction of the vehicle body, a transport means that transports the vehicle body along the transport direction, and a current condition data acquisition means that acquires data on current conditions based on measurement results when a current is applied from the plurality of electrodes to the plurality of vehicle bodies in the electrocoating tank that are continuously transported by the transport means, the current condition data acquisition means including an electrode selection means that selects a specific electrode from the plurality of electrodes, and a positional range in which a current is expected to be applied to the vehicle body from the specific electrode when the vehicle body is transported along the transport direction. The gist of the electrocoating equipment is that it comprises a current application range definition means for defining a current application range based on the shape information of the vehicle body and the design information of the equipment, a current measurement means for actually measuring the current applied to the vehicle body from the specific electrode according to the moving position of the vehicle body while transporting the vehicle body, a comparison calculation means for comparing the center position of the current application range with the peak position of the measured current and calculating the amount of deviation of the peak position from the center position, a current application range redefinition means for offsetting the center position so that it coincides with the peak position based on the amount of deviation and redefining the current application range, and a current application range application means for applying the redefined current application range to the remaining electrodes of the plurality of electrodes excluding the specific electrode.

In the invention described in claim 4, the current measuring means actually measures the current applied to the vehicle body from a specific electrode, so that the current value of the current applied to the vehicle body can be accurately known. Moreover, the comparison and calculation means calculates the amount of deviation of the peak position of the measured current from the center position of the current application range, and the current application range redefinition means offsets the center position so that it coincides with the peak position to redefine the current application range. As a result, the deviation between the redefined current application range and the actual current application range is reduced, so that an accurate current value can be obtained by measuring the current in the redefined current application range. Therefore, based on the obtained current value (measurement result), accurate data regarding the current application conditions, specifically, data showing the relationship between the current value and the film thickness, can be obtained. Therefore, by adjusting the voltage value applied to the vehicle body based on the obtained data, the paint film formed on the surface of the vehicle body can be set to a targeted thickness range, improving the paint quality of the vehicle body.

Furthermore, in claim 4, the current application range application means applies the redefined current application range to the remaining electrodes excluding the specific electrode. In this way, even if a large number of electrodes are arranged in the electrodeposition tank, the current application range can be easily defined for all electrodes. As electrodeposition paint, cationic electrodeposition paint and anionic electrodeposition paint can be used, but from the viewpoint of rust prevention, it is preferable to use cationic electrodeposition paint.

As described above in detail, according to the inventions described in claims 1 to 4, the current applied to the vehicle body can be accurately measured, allowing the coating film formed on the surface of the vehicle body to be within a targeted thickness range.

FIG. 1 is a schematic cross-sectional view showing an electrodeposition coating facility according to an embodiment of the present invention. FIG. 4 is an explanatory diagram showing a method for adjusting the voltage value of an electrode. FIG. 4 is an explanatory diagram showing a method for defining a current application range. 6A and 6B are graphs showing a method for redefining the current application range. FIG. 13 is an explanatory diagram showing a method for adjusting the voltage value of an electrode in the prior art. FIG. 1 is an explanatory diagram illustrating a problem with the conventional technology.

An embodiment of the present invention will be described in detail below with reference to the drawings.

As shown in FIG. 1, the electrocoating equipment 10 includes an electrocoating tank 11 for storing electrocoating paint P1. In the electrocoating tank 11, the vehicle body W1 is transported while immersed in the electrocoating paint P1. The electrocoating tank 11 is composed of a tank upper portion 12 constituting the ceiling of the electrocoating tank 11, a tank bottom portion 13 constituting the floor of the electrocoating tank 11, and two side walls 14. The electrocoating tank 11 is also provided with an entrance 15 for carrying the vehicle body W1 into the electrocoating tank 11, and an exit 16 for carrying the vehicle body W1 out of the electrocoating tank 11. The electrocoating paint P1 in this embodiment is, for example, a paint that uses a cationic electrolytic resin as the main vehicle.

The electrocoating equipment 10 also includes a conveyor 21 (conveying means) that transports the vehicle body W1 in the transport direction (to the right in FIG. 1). The conveyor 21 lowers the vehicle body W1 while transporting it into the electrocoating tank 11 through the transport entrance 15, and raises the vehicle body W1 while transporting it out of the electrocoating tank 11 through the transport exit 16. The conveyor 21 includes a rail 22 that extends in the transport direction, and a number of hanger rails 23 that are attached to the rail 22 and transport the vehicle body W1 by suspending it. Each hanger rail 23 is further provided with a pulse transmitter 24 that periodically transmits a pulse signal.

As shown in FIG. 1, multiple electrodes 31 are arranged in the electrodeposition tank 11. Each electrode 31 consists of side electrodes 32, 33 installed on the side wall 14 of the electrodeposition tank 11, and a bottom electrode 34 installed on the tank bottom 13 of the electrodeposition tank 11. The side electrode 32 is in the form of a strip extending in the vertical direction and is arranged at intervals along the conveying direction of the vehicle body W1. The side electrode 33 and the bottom electrode 34 are also in the form of a strip extending in the conveying direction and are arranged at intervals along the conveying direction. A cable 35 (see FIG. 2) is connected to each electrode 31. Each cable 35 is drawn out of the electrodeposition tank 11.

Next, we will explain the electrical configuration of the electrocoating equipment 10.

As shown in FIG. 1, the electrocoating equipment 10 includes a personal computer 50, which includes a control device 51 for controlling the entire equipment. The control device 51 includes a CPU 52, a ROM 53, a RAM 54, an input/output circuit, and the like. The CPU 52 functions as a learning unit 55. The keyboard 56 and the display 57 of the personal computer 50 are electrically connected to the CPU 52. The CPU 52 is also electrically connected to the conveyor 21 and each pulse transmitter 24, and controls them by various drive signals. In this embodiment, each electrode 31 is electrically connected to the CPU 52 by connecting the electrodes 31 to the control device 51 via a cable 35. The pulse signals output from each pulse transmitter 24 are periodically input to the CPU 52. Furthermore, the ROM 53 is preset (stored) with production takt time information indicating the working time of electrocoating each vehicle body W1.

Next, we will explain the electrodeposition coating method using the electrodeposition coating equipment 10.

First, the CPU 52 outputs a drive signal to the conveyor 21, causing the vehicle bodies W1 (hanger rails 23) to be continuously carried into the electrodeposition tank 11 through the carry-in entrance 15, and the vehicle bodies W1 to be continuously carried out of the electrodeposition tank 11 through the carry-out exit 16. Then, when the vehicle bodies W1 carried into the electrodeposition tank 11 are immersed in the electrodeposition paint P1, a current is applied to the vehicle body W1 from each electrode 31 arranged in the electrodeposition tank 11, and electrodeposition coating is performed on the vehicle body W1. As a result, a coating film is formed on the surface of the vehicle body W1.

If the coating thickness is within the desired range, electrodeposition coating continues without any adjustments. However, if the coating thickness fluctuates and deviates from the desired range, the CPU 52 acquires data on the current flow conditions based on the measurement results when current is applied from each electrode 31 to multiple vehicle bodies W1 in the electrodeposition tank 11 that are continuously transported by the conveyor 21. In other words, the CPU 52 functions as a "current flow condition data acquisition means."

Specifically, first, the CPU 52 performs an electrode selection step and arbitrarily selects a specific electrode 31 (side electrode 32) from among the multiple electrodes 31. That is, the CPU 52 functions as an "electrode selection means". In the subsequent current application range definition step, the CPU 52 defines a current application range 61 (see FIG. 3) based on the shape information of the vehicle body W1 pre-stored in the ROM 53 and the design information of the electrocoating equipment 10. That is, the CPU 52 functions as a "current application range definition means". The current application range 61 is a positional range in which a current is expected to be applied from the specific side electrode 32 to the vehicle body W1 when the vehicle body W1 is transported along the transport direction. Specifically, first, the CPU 52 calculates the distance from the reference position S1 (see FIGS. 1 and 3) near the entrance 15 of the electrocoating tank 11 to the specific side electrode 32 based on the design information of the equipment, and stores (sets) the calculated distance in the RAM 54 as electrode distance information. The CPU 52 also calculates the distance from the reference position S1 for each of the remaining side electrodes 32, excluding the specific side electrode 32, based on the equipment design information, and stores (sets) these calculated distances in the RAM 54 as electrode distance information.

3, the CPU 52 calculates the length L1 (width) of the specific side electrode 32 in the conveying direction based on the design information of the equipment, and stores (sets) the calculated length L1 in the RAM 54. Furthermore, when the overall length of the vehicle body W1 is L2, the CPU 52 sets the length from the reference position S1 to the rear end of the vehicle body W1 as the rear range. The CPU 52 also sets the length from the reference position S1 to the front end of the vehicle body W1 as the front range. The CPU 52 then reflects the set rear range as the upstream current application range starting from the upstream end S2 of the specific side electrode 32, and reflects the set front range as the downstream current application range starting from the upstream end S2. As a result, the total range of the upstream current application range and the downstream current application range is defined as the current application range 61.

In the subsequent current measurement step, the CPU 52 actually (in-line) measures the current applied to the vehicle body W1 from a specific side electrode 32 according to the moving position of the vehicle body W1 while transporting the vehicle body W1 (see FIG. 2). That is, the CPU 52 has a function as a "current measurement means". Specifically, the CPU 52 first selects one vehicle body W1 from among a plurality of (here, six) vehicle bodies W1 immersed in the electrochemical paint P1. In more detail, the CPU 52 counts the number of pulse signals (number of pulses) output from the corresponding pulse transmitter 24 while the vehicle body W1 (hanger rail 23) moves from the reference position S1 to the current position. The number of pulses is counted for all vehicle bodies W1 immersed in the electrochemical paint P1. Then, the CPU 52 calculates the moving distance of each vehicle body W1 from the reference position S1, i.e., the current position of each vehicle body W1, based on the counted number of pulses. The CPU 52 also calculates the residence time of each vehicle body W1 in the electrodeposition tank 11 (the time it is immersed in the electrodeposition paint P1) based on the current position of each vehicle body W1.

Next, the CPU 52 selects electrode distance information indicating the distance from the reference position S1 to the specific side electrode 32 from among the multiple pieces of electrode distance information stored in the ROM 53. Furthermore, the CPU 52 selects the vehicle body W1 from among the multiple vehicle bodies W1 that will pass the specific side electrode 32, whose calculated movement distance of the vehicle body W1 is closest to the distance indicated by the selected electrode distance information. The CPU 52 then outputs a drive signal to an ammeter (not shown) to measure the current value and peak value of the current applied from the specific side electrode 32 to the selected vehicle body W1. Note that data regarding the current value and peak value, and data regarding the type (shape information) of the vehicle body W1 are stored in the RAM 54 for each vehicle body W1.

Note that the current application range 61, which is the range in which the current is expected to be applied, may deviate from the actual current application range 62 due to a shift in the mounting position of the vehicle body W1 relative to the hanger rail 23 or a change in the type of vehicle body W1 mounted on the hanger rail 23. Therefore, in this embodiment, a process is performed to correct the deviation of the current application range 61. Specifically, in the comparison calculation step, the CPU 52 compares the center position A1 of the current application range 61 with the peak position A2 of the measured current, and calculates the deviation amount A3 of the peak position A2 from the center position A1 (see FIG. 4(a)). That is, the CPU 52 functions as a "comparison calculation means." Note that the peak position A2 refers to the position where the current value of the current applied to the selected vehicle body W1 is the peak value.

In the subsequent current application range redefinition step, the CPU 52 automatically offsets the center position A1 based on the deviation amount A3 so that it coincides with the peak position A2, and redefines the current application range 61 (see FIG. 4(b)). That is, the CPU 52 functions as a "current application range redefinition means". Furthermore, the CPU 52 performs a current application range application step, and applies the redefined current application range 61 to the remaining side electrodes 32 excluding the specific side electrode 32 among the side electrodes 32. That is, the CPU 52 functions as a "current application range application means".

Then, in the cumulative current value calculation step, the CPU 52 measures the current in the redefined current application range 61 to calculate the cumulative current value, which is the amount of current applied per unit time. Note that the area of the region R1 (see FIG. 4(b)) surrounded by the horizontal axis and the current value graph in the current application range 61 indicates the amount of current applied (cumulative current value) from a specific side electrode 32 to one vehicle body W1. The cumulative current value is calculated for all electrodes 31 and all vehicle bodies W1, and is stored in the RAM 54 while being linked to the manufacturing number (ID).

Then, the CPU 52 determines an appropriate voltage value to be applied to the vehicle body W1 from the side electrode 32. The appropriate voltage value is estimated by the learning unit 55 from past data (data such as the integrated current value, the type of the vehicle body W1, and the film thickness of each part of the vehicle body W1) stored in the RAM 54. The learning unit 55 learns what voltage value is necessary to obtain an appropriate film thickness. In this embodiment, the applied voltage value is estimated, and the film thickness is measured by a film thickness meter 71 (see FIG. 2) for multiple parts of the vehicle body W1 where the electrocoating has been completed. The film thickness meter 71 is not particularly limited, and may be appropriately selected from, for example, an electromagnetic film thickness meter, an eddy current film thickness meter, an infrared film thickness meter, an ultrasonic film thickness meter, and a spectroscopic interference film thickness meter. The film thickness meter 71 is connected to the computer 50 via a cable (not shown). Therefore, data on the measured film thickness (film thickness measurement data) is transmitted to the computer 50 via the cable and stored in the RAM 54.

As a result, the learning unit 55 can obtain new data on "what voltage value is necessary to achieve an appropriate coating thickness." The learning unit 55 then stores the obtained data in the RAM 54 as learned data (past data). Thereafter, as shown in FIG. 2, the CPU 52 determines a voltage value based on the learned data stored in the RAM 54, and applies a voltage from the side electrode 32 to the vehicle body W1 based on the determined voltage value. In addition to adjusting the voltage value applied from the side electrode 32 to the vehicle body W1, the CPU 52 also adjusts the position of the side electrode 32, etc. As a result, the coating formed on the surface of the vehicle body W1 is adjusted to a targeted thickness range.

Therefore, this embodiment can provide the following advantages:

(1) In this embodiment, in the current measurement step, the current applied to the vehicle body W1 from the specific side electrode 32 is actually measured (in-line), so that the current value of the current applied to the vehicle body W1 can be accurately known. Moreover, in the comparison calculation step, the deviation amount A3 of the peak position A2 of the measured current from the center position A1 of the current application range 61 is calculated (see FIG. 4(a)), and in the current application range redefinition step, the center position A1 is offset so as to coincide with the peak position A2, and the current application range 61 is redefined (see FIG. 4(b)). As a result, the deviation between the redefined current application range 61 and the actual current application range 62 becomes small, so that an accurate current value can be obtained by measuring the current in the redefined current application range 61. Therefore, based on the obtained current value (measurement result), accurate data on the current application conditions, specifically, data showing the relationship between the integrated current value and the film thickness, can be obtained. Therefore, by adjusting the voltage value applied to the vehicle body W1 based on the acquired data, the paint film formed on the surface of the vehicle body W1 can be adjusted to a desired thickness range, improving the paint quality of the vehicle body W1.

Note that a large number of side electrodes 32 (approximately 100 to 160) are typically placed in the electrodeposition tank 11. For this reason, accurately defining the current application range 61 for each side electrode 32 is unrealistic because it requires a great deal of effort. Therefore, in this embodiment, a current application range application step is performed, and the redefined current application range 61 is applied to the remaining side electrodes 32, excluding the specific side electrode 32. In this way, even if a large number of side electrodes 32 are placed in the electrodeposition tank 11, the current application range 61 can be easily defined for all of the side electrodes 32.

(2) In this embodiment, various processes such as detecting the peak value of the current value and calculating the amount of electricity (coulomb amount) by integrating the current value are performed, so that data showing the relationship between the current value and the film thickness can be collected for each vehicle body W1. This makes it possible to secure a wealth of data.

(3) In this embodiment, the current applied to the vehicle body W1 from a specific side electrode 32 is actually measured (in-line). In this case, the CPU 52 (learning unit 55) can quickly estimate the appropriate film thickness based on the measured current (integrated current value), and therefore can adjust the voltage to adjust the film thickness more quickly than in the conventional technology in which the current value is calculated (offline) based on the design information of the equipment.

(4) In this embodiment, the appropriate voltage value to be applied from the side electrode 32 to the vehicle body W1 is estimated based on the learned data obtained by the learning unit 55, so the paint film can be easily adjusted to the desired thickness range by adjusting the voltage value, and the paint quality is stabilized. Moreover, if the learning unit 55 is given more opportunities to learn, the estimated voltage value is optimized, and the paint quality is further stabilized.

The above embodiment may be modified as follows:

In the above embodiment, the CPU 52 (learning unit 55) estimated the voltage value that will result in an appropriate film thickness based on data indicating the relationship between the integrated current value and the film thickness. However, the learning unit 55 may also estimate the voltage value based on data indicating the relationship between the current value (e.g., peak value) and the film thickness.

In the above embodiment, the film thickness was adjusted by adjusting the position of the side electrode 32 in addition to adjusting the voltage value applied from the side electrode 32 to the vehicle body W1. However, the film thickness may be adjusted only by adjusting the voltage value.

Next, in addition to the technical ideas described in the claims, the technical ideas grasped by the above-mentioned embodiments are listed below.

(1) In any one of claims 1 to 3, the current application range definition step includes a step of measuring the distance from a reference position to the specific electrode, a step of measuring the length of the specific electrode in the transport direction, a step of setting the length from the reference position to the rear end of the vehicle body as a rear range, a step of setting the length from the reference position to the front end of the vehicle body as a front range, and a step of reflecting the set rear range as an upstream current application range starting from the upstream end of the specific electrode and reflecting the set front range as a downstream current application range starting from the upstream end. This is a method for acquiring current condition data in an electrodeposition coating facility, characterized in that the current application range is defined as the total range of the upstream current application range and the downstream current application range.

(2) The electrocoating equipment according to claim 4, further comprising a learning unit that learns the relationship between the film thickness and the voltage value, and a storage means that stores the data that indicates the relationship between the film thickness and the voltage value learned by the learning unit as learned data, and the current supply condition data acquisition means determines the voltage value to be applied to the vehicle body from the specific electrode based on the learned data stored in the storage means.

10...electrodeposition coating equipment 11...electrodeposition tank 21...conveyor as transport means 22...rail 23...hanger rail 24...pulse generator 31...electrode 52...CPU as current application condition data acquisition means, electrode selection means, current application range definition means, current measurement means, comparison calculation means, current application range redefinition means, and current application range application means
61...Current application range A1...Center position A2...Peak position A3...Displacement amount P1...Electrodeposition paint S1...Reference position W1...Vehicle body

Claims (4)

A method for acquiring data on current application conditions based on measurement results when current is applied from a plurality of electrodes disposed in an electrodeposition tank to a plurality of vehicle bodies in the electrodeposition tank that are continuously transported by a transport means, the method comprising the steps of:
an electrode selection step of selecting a specific electrode from the plurality of electrodes;
a current application range definition step of defining a current application range, which is a positional range in which a current is expected to be applied to the vehicle body from the specific electrode when the vehicle body is transported along a transport direction, based on shape information of the vehicle body and design information of equipment;
a current measuring step of actually measuring a current applied to the vehicle body from the specific electrode in accordance with a moving position of the vehicle body while transporting the vehicle body;
a comparison and calculation step of comparing a center position of the current application range with a peak position of the measured current and calculating an amount of deviation of the peak position from the center position;
a current application range redefining step of offsetting the center position so as to coincide with the peak position based on the deviation amount, and redefining the current application range;
A current application range application step of applying the redefined current application range to the remaining electrodes among the plurality of electrodes excluding the specific electrode. the conveying means includes a rail and a plurality of hanger rails that are provided on the rail and that suspend and convey the vehicle body,
A pulse transmitter that periodically transmits a pulse signal is provided on each of the hanger rails,
The method for acquiring current condition data in an electrocoating equipment as described in claim 1, characterized in that the moving distance of the vehicle body suspended on the hanger rail from a reference position is calculated based on the number of pulse signals transmitted from the pulse transmitter. The method for acquiring current condition data in an electrodeposition coating facility according to claim 1 or 2, further comprising a step of calculating an integrated current value, which is an amount of current applied per unit time, by measuring the current in the redefined current application range. an electrodeposition tank for storing an electrodeposition paint and for transporting a vehicle body while the vehicle body is immersed in the electrodeposition paint;
A plurality of electrodes are disposed in the electrodeposition tank and are spaced apart along the conveying direction of the vehicle body;
a conveying means for conveying the vehicle body along the conveying direction;
and a current condition data acquisition means for acquiring data on current conditions based on a measurement result when a current is applied from the plurality of electrodes to the plurality of vehicle bodies in the electrodeposition tank that are continuously transported by the transport means,
The energization condition data acquisition means
an electrode selection means for selecting a particular electrode from the plurality of electrodes;
a current application range definition means for defining a current application range, which is a positional range in which a current is expected to be applied to the vehicle body from the specific electrode when the vehicle body is transported along the transport direction, based on shape information of the vehicle body and design information of equipment;
a current measuring means for actually measuring a current applied to the vehicle body from the specific electrode in accordance with a moving position of the vehicle body while the vehicle body is being transported;
a comparison and calculation means for comparing a center position of the current application range with a peak position of the measured current and calculating an amount of deviation of the peak position from the center position;
a current application range redefining means for offsetting the center position so as to coincide with the peak position based on the deviation amount, and redefining the current application range;
and a current application range application means for applying the redefined current application range to the remaining electrodes of the plurality of electrodes excluding the specific electrode.

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