Winding defect inspection device, winding defect inspection system, and winding defect inspection method

Abstract

This defect inspection device for a winding which is run under the application of a constant tension in order to be wound around a wound member (22) is provided with an ion generating means (4) for generating ions that surround the outer periphery of the winding (1), the ion generating means (4) being disposed along the running path of the winding (1) leading to the wound member (22), a current detecting means (31) for detecting a current flowing through the winding as a result of electric charges that are carried by the ions entering from a defective portion of the winding, and a defect presence / absence determining means (33) for determining the presence or absence of a defect of the winding (1) on the basis of the result of a comparison between the output of the current detecting means (31) and a predetermined defect presence / absence threshold, the defect inspection device being capable of detecting defects of the running winding (1) and being capable of preventing breakdown of an insulating layer of the winding (1) during the detection.

Description

Winding defect inspection device, winding defect inspection system, and winding defect inspection method

[0001] The present disclosure relates to a winding defect inspection device, a winding defect inspection system, and a winding defect inspection method.

[0002] If there are defects such as scratches or pinholes in the insulating layer of the windings of a rotating electric machine, the insulation between the winding and the winding core or between the winding and ground will be reduced. This can cause insulation breakdown between adjacent windings in the coil that makes up the winding, which can lead to problems such as reduced performance of the rotating electric machine, burnout, and electrical leakage. For this reason, rotating electric machines require inspection of their windings for defects.

[0003] Defects in the windings can be detected by applying a voltage to the windings while the train is running and detecting the discharge current that occurs in the defective part of the winding. However, if the discharge current is not limited, the insulation layer of the windings may be destroyed, causing the defect to expand further. Therefore, it is necessary to prevent the insulation layer from being destroyed when inspecting for winding defects.

[0004] Conventional winding defect inspection technology involves detecting large flaws caused by friction between the winding and the nozzle that guides the winding. To do this, a winding defect detection device is used that places a fixed resistor between the inspection power supply and the winding to limit the current that flows during flaw inspection, thereby preventing the winding from burning out (see, for example, Patent Document 1).

[0005] Patent No. 6408229

[0006] According to the technology disclosed in Patent Document 1, a fixed resistor is inserted between the inspection power supply and the winding, limiting the current flowing to large defects of about 1 mm caused by friction between the winding and the nozzle that guides the winding to the wound member. This prevents burnout of the damaged part of the winding and makes it possible to inspect the winding for defects.

[0007] On the other hand, when inspecting for inherent defects in the windings, such as pinholes or dents in the thin insulation layer, the required power supply voltage and discharge current state vary depending on the size of the defect, so when using a fixed resistor to inspect for large and small defects or weak defects such as dents in the thin insulation layer, applying a low voltage will allow the detection of large defects but will not allow the detection of small and weak defects, while applying a high voltage will allow the detection of small and weak defects but may damage the winding insulation layer when detecting large defects. Therefore, there is a problem in that fixed resistors cannot simultaneously detect all types of defects and prevent damage to the winding insulation layer.

[0008] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a winding defect inspection device that can reliably detect defects in windings while a train is running.

[0009] The defect inspection device for windings disclosed in the present application is a defect inspection device for windings that are run under a constant tension in order to be wound around a wound member, and is equipped with: ion generation means that is arranged along the running path of the winding to the wound member and generates ions that surround the outer periphery of the winding; current detection means that detects the current that flows in the winding as a result of the electric charges carried by the ions entering through a defective portion of the winding; and defect presence / absence determination means that determines the presence or absence of a defect in the winding based on the result of comparing the output of the current detection means with a predetermined defect presence / absence threshold.

[0010] The winding defect inspection device disclosed in the present application can reliably detect defects in windings while the train is running by detecting the current that is generated when the charge of ions generated by the ion generating means penetrates into defective parts of the windings.

[0011] FIG. 1 is a block diagram showing the configuration of a winding defect inspection device according to a first embodiment. FIG. 2 is a diagram explaining the principle of detecting winding defects using ions. FIG. 3 is a diagram showing the output of a minute ammeter, the output of an inspection signal processing means, and the output of a defect presence / absence determination means of the winding defect inspection device according to the first embodiment. FIG. 4 is a diagram showing an example circuit configuration of the inspection signal processing means and the defect presence / absence determination means according to the first embodiment. FIG. 5 is a block diagram showing the configuration of a winding defect inspection device according to a second embodiment. FIG. 6 is a block diagram showing the configuration of a winding defect inspection device according to a third embodiment. FIG. 7 is a block diagram showing the configuration of a winding defect inspection device according to a fourth embodiment. FIG. 8 is a diagram showing the relationship between a motor coil wound around a core, an ion generating means, and an encoder during defect detection in a winding defect inspection system according to a fifth embodiment. FIG. 9 is a diagram explaining the relationship between distances for calculating defect positions in defect detection in the winding defect inspection system according to the fifth embodiment. FIG. 10 is a flow chart explaining the measurement procedure of the defect inspection system according to the fifth embodiment. FIG. 11 is a diagram showing an example hardware configuration of a controller of the defect inspection system according to the fifth embodiment.

[0012] A preferred embodiment of a defect inspection device for a winding according to the present application will be described below with reference to the drawings. The same contents and corresponding parts are designated by the same reference numerals, and detailed description thereof will be omitted. Similarly, in the following embodiments, redundant description of components designated by the same reference numerals will be omitted.

[0013] 1 is a block diagram of a defect inspection device for windings of a rotating electrical machine according to embodiment 1. The defect inspection device for windings 1 includes a winding machine main body 2 that winds windings 1 around a wound member 22 to manufacture winding components for a rotating electrical machine, and a defect inspection unit 3 for windings 1.

[0014] The winding machine main body 2 has a winding section 21 from which the winding 1 is unwound, a wound member 22 around which the winding 1 is wound, a nozzle 23 that guides the winding 1 when winding the winding 1 around the wound member 22, and a housing 24 for attaching the nozzle 23.

[0015] The defect inspection unit 3 is mainly composed of the following components (1) to (4), and detects defects in the winding 1 while preventing damage to the insulating layer 12 (see FIG. 2) of the winding 1 during the detection. (1) The winding 1 wound around the unwinding unit 21 travels while being given a constant tension by a tensioner 90, and an ion generating means 4 is disposed midway along the path leading to the wound member 22. (2) A minute ammeter 31 detects a current 45 flowing through the winding 1 due to ions generated by the ion generating means 4 when the winding 1 has a defect such as a pinhole. (3) An inspection signal processing means 32 amplifies the output of the minute ammeter 31 and performs noise processing. (4) A defect presence / absence determining means 33 determines the presence or absence of a defect based on the output of the inspection signal processing means 32.

[0016] <Ion Generating Means> The ion generating means 4 comprises a discharge needle 43, an ion generator 42 that generates a corona discharge at the discharge needle 43, and a power supply 41 that applies a voltage to the ion generator 42. A voltage is applied from the power supply 41 to the ion generator 42, causing the discharge needle 43 to generate a corona discharge. This corona discharge ionizes the air around the discharge needle 43, generating positive or negative ions 44. As the winding 1 passes through an atmosphere of the generated positive or negative ions, the outer periphery of the winding 1 is surrounded by ions 44 that have either a positive or negative charge 441. Because the ions 44 can surround the entire outer periphery of the winding 1, for example, the discharge needle 43 may be facing in the direction of the winding 1 opposite the side where the defect 13 is located. In other words, the defect can be detected regardless of the orientation of the defect in the winding 1.

[0017] <Explanation of Defect Detection Operation> Defect detection is performed by the defect inspection unit 3. The defect inspection unit 3 is composed of a microcurrent meter 31, an inspection signal processing means 32, and a defect presence / absence determination means 33. First, the generation of current when the winding 1 is surrounded by ions 44 will be explained. For ease of explanation, the parts necessary for explanation are simplified from the block diagram in FIG. 1 and shown in FIG. 2. Suppose the winding 1 has a pinhole defect 13, for example, 100 μm wide. When the defect 13 passes through a space where an ion 44 exists, an electric charge 441 carried by the ion 44 enters the winding 1 from the defect 13 and flows along the copper core 11 of the winding 1, generating a current 45.

[0018] If the defect 13 in the winding 1 is large, for example, 100 μm, the amount of charge 441 entering the copper core 11 of the winding 1 increases, and the current 45 increases to, for example, 4 μA, as indicated by signal 45a, as shown in Figure 3(a). In Figure 3(a), the vertical axis represents the magnitude of the current 45, and the horizontal axis represents the elapsed time. Note that when ions 44 are generated, the concentration of ions 44, or in other words, the total amount of charge 441 carried by ions 44, is set low, for example, to 20 μA, so as not to destroy the insulating layer 12 of the winding 1.

[0019] In contrast, if the defect 13 in the winding 1 is small, for example, 50 μm, the amount of charge 441 entering the copper core 11 of the winding 1 is small, and the magnitude of the current 45 is small, for example, 2 μA, as indicated by signal 45b. Also, if there is no defect 13 in the winding 1, the magnitude of the current 45 is 0 μA, as indicated by signal 45c.

[0020] Next, we will explain how to detect defects 13 in winding 1. Current 45 flows to earth via minute ammeter 31 as signals 45a and 45b in Figure 3(a), so current 45 can be detected by minute ammeter 31. Minute ammeter 31 converts a current of, for example, 1 μA into a voltage of 100 mV and outputs it.

[0021] The inspection signal processing means 32 amplifies and removes noise from the voltage output converted by the minute ammeter 31. Figure 3(b) shows voltage waveform signals 32a and 32b obtained by converting current waveform signals 45a and 45b into voltages using the minute ammeter 31 and processing them in the inspection signal processing means 32. The defect presence / absence determination means 33 receives the signals 32a and 32b processed by the inspection signal processing means 32 and compares them with a defect presence / absence threshold 32d to determine whether or not a defect is present in the winding 1. In Figure 3(b), the vertical axis represents the magnitude of the voltage, and the horizontal axis represents the elapsed time, as in Figure 3(a). Because signal 32a is greater than the defect presence / absence threshold 32d between times t2 and t3, a defect presence / absence signal 33a of high level "H" indicating a defect is output to the controller 34 of the winding machine main body 2, as shown in Figure 3(c). Furthermore, since signal 32b between times t4 and t5 is also greater than defect presence / absence threshold 32d, defect presence / absence signal 33b of high level "H" indicating a defect is output. In response to the high level "H" signal, controller 34 may alert the operator by sounding an alarm, displaying a message on the display, etc., and since the location of the defect can be identified from the time when defect presence / absence signals 33a and 33b were generated, measures such as stopping winding machine main body 2 to remove or repair the defective portion may be taken. In Figure 3(c), the vertical axis represents the signal "H" or "L", and the horizontal axis represents the elapsed time, as in Figures 3(a) and 3(b).

[0022] The defect presence / absence threshold 32d is selected in advance using a preliminary test or the like. In the preliminary test, for example, (a) a winding determined to be defect-free using a JIS pinhole test and (b) a winding determined to be defective are prepared. The defect-free winding (a) is wound using a defect inspection device, and the current measured by the minute ammeter 31 and the voltage converted from the current are recorded. In this case, only noise is recorded, so a voltage higher than the noise voltage is set as the defect presence / absence threshold 32d to prevent the noise from being erroneously detected as a defect. In addition, the voltage applied to the ion generator 42 of the ion generating means 4 is set so that the output of the minute ammeter 31 when the defective winding (b) is wound using the defect inspection device, i.e., the minimum value of the voltage at which a defect is determined to exist, is greater than the defect presence / absence threshold 32d.

[0023] <Specific Configurations of the Minute Ammeter, Inspection Signal Processing Means, and Defect Presence / Absence Determination Means> The minute ammeter 31 may be any device capable of detecting minute currents and converting them into voltage. For example, a commercially available minute ammeter 5450 may be used. Furthermore, the terminal 311 of the minute ammeter 31 does not output a voltage. That is, the voltage of the terminal 311 may be set to 0 V, so that the charge 441 naturally flows to the ground. Furthermore, the terminal 311 may output a positive voltage of, for example, 50 V, so that the charge 441 is actively drawn into the minute ammeter 31. This increases the amount of charge 441 flowing through the minute ammeter 31, thereby increasing the detection signal and improving detection accuracy.

[0024] FIG. 4 shows an example of the circuits of the inspection signal processing means 32 and the defect presence / absence determination means 33. The inspection signal processing means 32 uses an amplifier 321 (generally referred to as an amplifier; surrounding components other than resistors are omitted) for signal amplification processing to amplify the voltage signal output from the signal converted to voltage by the minute ammeter 31. The defect presence / absence determination means 33 uses a comparator 331 (surrounding components are omitted) to compare the output of the amplifier 321 with a defect presence / absence threshold 32d. If the output of the amplifier 321 is greater than the defect presence / absence threshold 32d, the comparator 331 goes high level "H" and outputs a signal of, for example, 5 V. If the output of the amplifier 321 is less than the defect presence / absence threshold 32d, the comparator 331 goes low level "L" and outputs a signal of, for example, 0 V. The output of the comparator 331 is shown in FIG. 3(c). A filter (for example, a low-pass filter) may be placed between the amplifier 321 and the comparator 331 to remove noise contained in the current detected by the minute ammeter 31 .

[0025] As described above, by allowing charge from ion generating means 4 to penetrate into defective portions of the winding, defects in the running winding can be detected with high reliability, and damage to the winding's insulating layer can be prevented when detecting defects. Furthermore, because ions 44 surround the outer periphery of the winding as the winding passes through ion generating means 4, defects can be detected regardless of the orientation of the defect even if discharge needle 43 is not pointing toward defect 13, for example, if discharge needle 43 is pointing toward the outer periphery of the winding on the side opposite defect 13. Furthermore, compared to methods of detecting defects in windings by irradiating the winding with an electron beam, this method has the advantage of simplifying the configuration because it does not require equipment for creating a vacuum environment.

[0026] Embodiment 2. Fig. 5 is a block diagram showing a defect inspection device for a winding of a rotating electrical machine according to embodiment 2. In this figure, the same reference numerals as in Fig. 1 indicate the same or corresponding parts.

[0027] The defect inspection unit 3 is mainly composed of the following components (1) to (4), and detects defects 13 in the winding 1 while preventing damage to the insulating layer 12 of the winding 1 during the detection. (1) The winding 1 wound around the unwinding unit 21 travels while being given a constant tension by a tensioner 90, and an ion generating means 4a is disposed midway along the path leading to the wound member 22. (2) A minute ammeter 31 detects a current 45 flowing through the winding 1 due to ions generated by the ion generating means 4a when the winding 1 has a defect such as a pinhole. (3) An inspection signal processing means 32 amplifies the output of the minute ammeter 31 and performs noise processing. (4) A defect presence / absence determining means 33 determines the presence or absence of a defect based on the output of the inspection signal processing means 32.

[0028] <Ion Generating Means of Embodiment 2> As in Embodiment 1, ion generating means 4a according to Embodiment 2 includes a discharge needle 43, an ion generator 42 that generates a corona discharge at the discharge needle 43, and a power supply 41 that applies a voltage to the ion generator 42. Furthermore, ion generating means 4a according to Embodiment 2 includes a shielding box 46 made of a non-conductive material for limiting the range in which ions 44 are generated. The shielding box 46 is formed to extend from the ion generator 42 toward the winding 1 so as to surround the discharge needle 43, and may have a cylindrical or rectangular structure. When the shielding box 46 extends to the periphery of the winding 1 as shown in FIG. 5 , a through-hole 461 for passing the winding 1 is formed in the shielding box 46, and a lid 462 is provided for confining the ions 44 within the shielding box 46.

[0029] By limiting the range in which ions 44 are generated by the shielding box 46, the concentration of ions 44 can be increased. Therefore, even if the amount of generated ions 44 is the same as in the first embodiment, the amount of charge that enters the copper core 11 from the defect 13 in the winding 1 can be increased. This increases the signal detected by the microcurrent meter 31. Therefore, even small defects that cannot be detected by the first embodiment can be detected by the microcurrent meter 31. Furthermore, because the range in which ions 44 are generated is limited, when a defect 13 is detected, the position of the defect 13 can be more easily identified compared to the first embodiment based on the detection time, the running speed of the winding 1, and the width of the shielding box 46. Although a lid 462 is provided on the shielding box 46, the lid 462 is not necessary if the ions 44 can be confined within the shielding box 46.

[0030] As described above, in addition to the effects of embodiment 1, the defect inspection device of embodiment 2 is provided with a shielding box that limits the range of ion generation, thereby further improving the accuracy of defect detection and making it easier to identify the defect detection position.

[0031] Embodiment 3. Figure 6 is a block diagram showing a defect inspection device for a winding of a rotating electrical machine according to embodiment 3. In this figure, the same reference numerals as in Figure 1 indicate the same or corresponding parts.

[0032] The defect inspection unit 3 is mainly composed of the following components (1) to (4), and detects defects 13 in the winding 1 while preventing damage to the insulating layer 12 of the winding 1 during the detection. (1) The winding 1 wound around the unwinding unit 21 travels while being given a constant tension by a tensioner 90, and an ion generating means 4b is disposed midway along the path leading to the wound member 22. (2) A minute ammeter 31 detects a current 45 flowing through the winding 1 due to ions generated by the ion generating means 4b when the winding 1 has a defect such as a pinhole. (3) An inspection signal processing means 32 amplifies the output of the minute ammeter 31 and performs noise processing. (4) A defect presence / absence determining means 33 determines the presence or absence of a defect based on the output of the inspection signal processing means 32.

[0033] <Ion Generation Means of Embodiment 3> As in embodiment 1, ion generation means 4b according to embodiment 3 is composed of discharge needle 43, ion generator 42 that generates corona discharge in discharge needle 43, and power supply 41 that applies voltage to ion generator 42. Furthermore, ion generation means 4b of embodiment 3 has, between discharge needle 43 and winding 1, metal plate 47 that collects ions 44, brush 49 that contacts winding 1, and conductor 48 that conducts electric charge 441 of ions 44 collected on metal plate 47 to brush 49.

[0034] By providing metal plate 47, ions 44 actively move toward metal plate 47, and as ions 44 gather on metal plate 47, the amount of charge 441 that enters defect 13 in winding 1 via conductor 48 and brush 49 increases. This increases the signal detected by microcurrent meter 31, improving the accuracy of detecting minute defects without damaging insulating layer 12 of winding 1. Another advantage is that, because the range in which ions 44 are generated is limited to the contact area between brush 49 and winding 1, when defect 13 is detected, the location of defect 13 can be more easily identified than in embodiment 1 based on the detection time, the running speed of winding 1, and the width of brush 49. Furthermore, as in embodiments 1 and 2, defects can be detected regardless of the direction in which discharge needle 43 faces winding 1.

[0035] The maximum amount of charge 441 flowing through defect 13 is approximately 20 μA, which does not destroy insulating layer 12 of winding 1. Furthermore, because a high voltage is not applied to winding 1, discharge between defect 13 in winding 1 and a component of winding machine main body 2, such as nozzle 23, can be avoided.

[0036] As described above, the defect inspection apparatus of the third embodiment has the same effects as the first embodiment, and in addition, it is possible to further improve the accuracy of defect detection and to easily identify the defect detection position.

[0037] Embodiment 4. Figure 7 is a block diagram showing a defect location inspection device for a winding of a rotating electrical machine according to embodiment 4. In this figure, the same reference numerals as in Figure 1 indicate the same or corresponding parts.

[0038] The defect inspection unit 3 is mainly composed of the following components (1) to (5) and detects defects 13 in the winding 1 while preventing damage to the insulating layer 12 of the winding 1 during the detection. (1) The winding 1 wound around the unwinding unit 21 travels while being given a constant tension by a tensioner 90, and ion generating means 4a1 and 4a2 are disposed midway along the path leading to the wound member 22. (2) When the winding 1 has a defect such as a pinhole, the ion generating means 4a1 and 4a2 generate ions, which generate a current 45 that flows through the winding 1. (3) The inspection signal processing means 32 amplifies the output of the minute ammeter 31 and performs noise processing. (4) The defect presence / absence determining means 33 determines the presence / absence of a defect based on the output of the inspection signal processing means 32. (5) The ion generating means 4a1 and 4a2 have the same configuration as the ion generating means 4a described in the second embodiment and include a shielding box 46 for limiting the range of ion 44 generation. The shielding box 46 is formed to extend from the ion generator 42 in the direction of the winding 1 so as to surround the discharge needle 43, and may have a cylindrical or rectangular structure. When the shielding box 46 is extended to surround the winding 1 as shown in Figure 7, a through hole 461 is formed in the shielding box 46 to allow the winding 1 to pass through, and a lid 462 is provided to confine the ions 44 within the shielding box 46.

[0039] As described above, the difference between embodiment 4 and embodiment 1 is that two ion generating means 4a1, 4a2 are arranged at different positions along the running direction of winding 1 to surround the outer periphery of winding 1. The operation of the defect inspection device for winding 1 according to embodiment 4 is the same as that described in embodiments 1 and 2, except that defects 13 are detected by ions 44 that surround the outer periphery of winding 1 generated by ion generating means 4a2 in addition to ion generating means 4a1.

[0040] The operation of defect inspection for winding 1 will now be described. Ion generating means 4a1 and 4a2 are arranged, for example, 10 cm apart. Suppose the traveling speed of winding 1 is 500 mm / s. In this case, defect 13 in winding 1 passes through shielding box 46 of ion generating means 4a1 and then passes through shielding box 46 of ion generating means 4a2 0.2 seconds later. Therefore, minute ammeter 31 detects signal 45a or signal 45b shown in FIG. 3 twice, with a detection time difference of 0.2 seconds.

[0041] The detected current converted into a voltage by minute ammeter 31 is amplified by inspection signal processing means 32 and compared with defect presence / absence threshold value 32d by defect presence / absence determining means 33, and the presence or absence of a defect is determined as follows (A) to (C): (A) When defect presence / absence determining means 33 detects defect presence / absence signal 33a or defect presence / absence signal 33b shown in Figure 3(c) only once, that is, when a signal is detected for ions 44 of either one of ion generating means 4a1, 4a2, it is determined that there is no defect 13 in winding 1. 3(c) twice, i.e., when signals are detected for ions 44 from both ion generating means 4a1 and 4a2, controller 34 calculates the time difference between the two detected defect presence / absence signals 33a or 33b (for example, the time difference between the rise times of the defect presence / absence signals), and if the time difference is 0.2 seconds, it is determined that there is a defect 13 in winding 1, and as described in embodiment 1, the operator may be alerted by, for example, emitting an alarm sound or displaying an indication on the display, or measures may be taken such as stopping winding machine main body 2 so that the defect can be removed or repaired. (C) On the other hand, if the time difference is not 0.2 seconds, it is determined that minute ammeter 31 has detected noise, and there is no defect 13 in winding 1.

[0042] Although the present embodiment has been described with two ion generating means 4a1 and 4a2, two or more ion generating means may be arranged along the running direction of winding 1. In this case, the results of the multiple defect presence / absence signals may be determined by a majority circuit or the like. Furthermore, the configuration of ion generating means 4a1 and 4a2 in the present embodiment may be the same as that of ion generating means 4b shown in embodiment 3.

[0043] As described above, in addition to the effects of embodiment 1, the defect inspection device of embodiment 4 can further increase the probability and accuracy of defect detection by using multiple ion generating means to detect the same defect in the winding 1.

[0044] Embodiment 5. This section describes a method for identifying defect locations after a core 6 is used as the wound member 22 and a winding 1 is wound around the teeth of the core 6 via an insulator 7 to form a motor coil 5. FIG. 8( a) is a diagram showing the relationship between the motor coil 5 wound around the core 6, the ion generating means 4, and the encoder E in defect detection. In this diagram, the winding 1 is wound as the motor coil 5 when the teeth of the core 6 are viewed in the direction protruding toward the core back portion. The coil distance T1 is the length along the circumferential direction of the motor, and the coil distance T2 is the length along the axial direction of the motor. FIG. 8( b) is a perspective view showing the state in which the winding 1 is wound around the insulator 7 of the core 6 to form the motor coil 5. The winding as the motor coil 5 is performed by rotating a spindle to which the core 6 is attached.

[0045] Distance L from the discharge needle 43 of the ion generating means 4 to the tip of the nozzle 23 １ , the distance from the tip of the nozzle 23 to the motor coil 5 is L ２ , the distance T in the short direction of the motor coil 5 １ , longitudinal distance T ２ In addition, the elongation rate of the winding 1 under the winding tension is known in advance. An encoder E is placed between the discharge needle 43 and the nozzle 23, and the distance (length) is measured from the speed at which the winding 1 passes through the encoder E.

[0046] The controller 34 receives the signal from the defect presence / absence determination means 33 and the signal from the encoder E, and records the winding distance up to the defect detection and the winding distance after the defect detection, with the winding start distance of the motor coil 5 being the zero point. １ , L ２ , T １ , T ２ By executing the measurement procedure flow from the elongation rate of the winding 1 under the winding tension, it is possible to determine by calculation which turn and where on the motor coil 5 the defect is located.

[0047] The flow of the measurement procedure of such a defect inspection system is shown in Figure 9. When the winding machine main body 2 starts winding, the encoder E starts counting the distance (step S1). When a defect is detected (step S2), the encoder E counts the distance E at the time of detection. １ is acquired and stored in the controller 34 (step S3). １ At the same time as obtaining, distance E ２ A new count is started to obtain the total distance R of the winding 1 required to complete the winding (step S4). ｔｏｔａｌ and the distance E at which the defect was detected. １ (Step S5). When comparing, the distance E １ The known distance L at the start of winding １ and distance L ２ (See the distance relationships in FIG. 10).

[0048] Distance E １ +distance L １ +distance L ２ is the total distance R ｔｏｔａｌ (YES in step S5), the distance E １ +distance L １ +distance L ２ The defect position on the motor coil 5 is calculated based on the distance E at which the defect was detected and recorded in the controller 34 (step S6). １ The distance E from when the defect was detected to the present ２ By adding １ (Step S7), and the distance E １ In this case, the distance E2 is reset (step S8).

[0049] Distance E １ +distance L １ +distance L ２ is the total distance R ｔｏｔａｌ or the total distance R ｔｏｔａｌ If the difference is greater than the distance L1+L2 (No in step S5), it is assumed that a defect has occurred at a position within the range from the end of winding to a point located at the distance L1+L2. １ +distance L ２ -Distance E２ The defect position on the motor coil 5 corresponding to the distance E is calculated (see the distance relationships in FIG. 10) and recorded in the controller 34 (step S11). １ , distance E ２ is reset (step S12).

[0050] This measurement flow makes it possible to accurately determine the location of defects on the wound motor coil 5. For example, in the case of a one-tooth core motor, by excluding only the defective teeth in advance, it is possible to reduce the rate of defects in subsequent processes and reduce overall costs. In addition, even if a motor coil has a defect, by arranging the defective motor coil so that it is not adjacent when assembling the stator, it is possible to use the motor coil without the defect being an issue, and yield can be expected to increase.

[0051] Furthermore, the distance L1 from the discharge needle 43 to the tip of the nozzle 23 may be replaced with a distance L1A = L1 ± α / 2, taking into account the range α of ion generation from the discharge needle 43 in the range along the direction of the winding 1. This makes it possible to identify the location of a defect on the motor coil 5 based on the detection range that takes into account the range of ion generation in the winding 1.

[0052] An example of the hardware of the controller 34 is shown in FIG. 11 . It is composed of a processor 100 and a storage device 200. Although not shown, the storage device 200 includes a volatile storage device such as a random access memory and a non-volatile auxiliary storage device such as a flash memory. Alternatively, a hard disk auxiliary storage device may be used instead of the flash memory. The processor 100 executes a program input from the storage device 200 to perform the measurement flow shown in FIG. 9 , for example. In this case, the program is input from the auxiliary storage device to the processor 100 via the volatile storage device. Furthermore, the processor 100 may output data such as measurement values ​​and calculated defect positions to the volatile storage device of the storage device 200, or may store the data in the auxiliary storage device via the volatile storage device.

[0053] Although various exemplary embodiments and examples are described in this application, the various features, aspects, and functions described in one or more embodiments are not limited to the application of a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are contemplated within the scope of the technology disclosed in this specification. For example, this includes cases where at least one component is modified, added, or omitted, or where at least one component is extracted and combined with components of another embodiment.

[0054] 1: Winding, 2: Winding machine body, 3: Defect inspection section, 11: Copper core, 12: Insulating layer, 13: Defect, 21: Unwinding section, 22: Wound member, 23: Nozzle, 24: Housing, 31: Microcurrent meter, 32: Inspection signal processing means, 33: Defect presence / absence determination means, 34: Controller, 4, 4a, 4b, 4a1, 4a2: Ion generating means, 41: Power supply, 42: Ion generator, 43: Discharge needle, 44: Ion, 45: Current, 46: Shielding box, 47: Metal plate, 48: Conductor, 49: Brush, 90: Tensioner, 100: Processor, 200: Storage device, 311: Terminal, 441: Electric charge.

Claims

1. A defect inspection device for a winding which runs under a constant tension in order to be wound around a wound member, the device comprising: ion generating means arranged along the running path of the winding to the wound member, which generates ions which surround the outer periphery of the winding; current detecting means which detects the current flowing within the winding as a result of the electric charge carried by the ions entering through a defective portion of the winding; and defect presence / absence determining means which determines the presence or absence of a defect in the winding based on the result of comparing the output of the current detecting means with a predetermined defect presence / absence threshold.

2. A winding defect inspection device as set forth in claim 1, wherein the defect presence / absence threshold is a value greater than a noise voltage.

3. A winding defect inspection device as described in claim 1, characterized in that the ion generating means comprises a discharge needle, an ion generator which generates a corona discharge in the discharge needle, and a power supply which applies a voltage to the ion generator.

4. A winding defect inspection device as described in claim 3, wherein the voltage applied to the ion generator is set so that the minimum voltage value at which the defect presence / absence determination means determines that a defect exists is greater than the defect presence / absence threshold value.

5. A winding defect inspection device according to claim 3 or 4, further comprising a shielding box disposed so as to surround said discharge needle and said winding surrounded by said ions.

6. A winding defect inspection apparatus as claimed in claim 5, wherein said shielding box is formed of a non-conductive material.

7. A winding defect inspection device as claimed in any one of claims 3 to 6, characterized in that it comprises a metal plate between the discharge needle and the winding for collecting the ions, a brush in contact with the winding, and a conductor for conducting the electric charge of the ions collected on the metal plate to the brush.

8. A winding defect inspection device as described in any one of claims 3 to 7, characterized in that a plurality of the ion generating means are arranged along the running path of the winding, and defects in the winding are judged based on the result of comparing a plurality of current outputs of the current detecting means with the defect presence / absence threshold value.

9. A winding defect inspection device as described in any one of claims 1 to 8, characterized in that a terminal for inputting the current flowing through the winding of the current detection means is configured not to output a voltage, thereby allowing the charge to flow to earth.

10. A winding defect inspection device as described in any one of claims 1 to 8, characterized in that a terminal for inputting the current flowing through the winding of the current detection means outputs a voltage, thereby drawing the charge into the current detection means.

11. A winding defect inspection system comprising: a winding machine that winds up a winding into a motor coil; a defect inspection device as claimed in any one of claims 3 to 8; an encoder that is disposed between a discharge needle of said defect inspection device and said motor coil and detects the speed of said winding; and a controller that calculates the position of a defect in the winding wound into the motor coil based on the output of said encoder and a defect detection signal output by said defect inspection device.

12. A method for inspecting defects in windings, using a winding machine that winds a winding around a motor coil, a defect inspection device as defined in any one of claims 3 to 8, and an encoder that detects the speed of the winding between the discharge needle of the defect inspection device and the motor coil, in which the distance at the start of winding of the winding is set as the zero point, and the position of a defect in the winding is calculated based on the winding distance up to and after the defect is detected.

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