JP2019095390A - Electric wire flaw detector - Google Patents

Abstract

To enable even a small flaw of covered electric wire of a coil to be detected with high accuracy, and enable the size of the detected flaw to be identified and only a flaw of designated size to be detected without causing the size of a detectable flaw to change due to the amount of covered electric wire in a bobbin or the amount of windings of the coil.SOLUTION: A voltage consisting of an alternating current superimposed on a direct current via a resistor 31 is applied by a DC power supply 32 and an AC power supply 33 between a termination of covered electric wire accommodated in a bobbin 20 and a conductor with which a covered electric wire W led out from the bobbin 20 comes in contact inside a winding machine 10. When a flaw portion of the covered electric wire comes in contact with the conductor inside the winding machine 10, an alternating current flows to the resistor 31 through the capacitance component of a covered electric wire wound and accommodated inside the bobbin 20 and an electric conduction check circuit 34 checks the electric conduction state of the covered electric wire by a voltage generated between both terminals of the resistor and detects a flaw of the covered electric wire.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wire flaw detection device used when winding a coated wire to form a coil for magnetic field generation.

  As a method of applying a winding to the core of an electromagnetic device such as a motor or a dynamo or a transformer, a method of directly winding a coated electric wire around those cores by a winding machine to form a coil, and forming a coil in advance by the coated electric wire There is a method of inserting a coil into a core by a coil insertion device.

As a coated wire, a copper wire (in some cases, an aluminum wire) coated with enamel is generally used. As for the coated electric wire, it is desirable that the outer peripheral surface such as a copper wire is completely covered with an insulating coating of enamel throughout the entire length after coil formation.
However, for example, the coated wire drawn from the bobbin to form a coil by a winding machine can be changed in traveling direction at a plurality of locations by a guide tube, a winding nozzle, etc. Strong rubbing with the line nozzle etc. may cause damage to the insulating coating. In addition, when the wound coil is inserted into the core by the coil insertion device, the insulating coating of the electric wire may be damaged.

If such a scratch is generated in the coated wire forming a coil for generating a magnetic field, a short circuit occurs between adjacent wires or the core when driving a motor or the like, an excessive current flows, and the function is deteriorated. Or, there is a possibility that it may lead to ignition by overheating.
Therefore, conventionally, during formation of a coil by a series winding machine, or when a coil is inserted into a core by a coil insertion device, a flaw of a covered electric wire forming the coil is detected, for example, as described in Patent Document 1 Some coil flaw detection devices are used.

In the wound detection device for the coil, the terminal connecting the end of the coated wire drawn from the bobbin or forming the coil and the portion (winding nozzle etc.) in contact with the coated wire in the winding machine or the coil insertion device are conducted. A direct current voltage is applied between the terminal and the current limiting resistor.
Then, the short-circuit current flowing through the wire when the portion where the insulating coating of the wire is damaged passes through the portion is detected by a photo coupler or the like to generate an alarm signal.

JP, 2015-175625, A

However, such a conventional coil flaw detection device applies a DC voltage between the coated wire and the conductor in contact with the DC power source to detect a short circuit current flowing when the flawed part passes through. Therefore, the current could not be detected unless the damage of the coated wire was very large.
The reason is that a long coated wire is wound in a coil shape and stored several times in a bobbin, and the coated wire in the bobbin B has a resistance component R and an equivalent circuit as shown in FIG. Since it has an inductance (reactance) component L, a DC voltage Es is applied between both ends a and b of the covered wire W in the bobbin B through the wound (corresponding to the switch SW) of the drawn wire which is drawn out Also, the sudden flow of current is prevented by the inductance component L, and the short circuit current i (t) gradually increases as shown in FIG.

Here, assuming that the short circuit time due to the wound of the coated wire during the winding operation by the winding machine is t, the short circuit current i (t) is i (t) = (Es / R) (1-e ^{−t / τ} ). τ is a time constant, and τ = L / R. When the short circuit current i (t) reaches the detection threshold ir, it is detected that there is a flaw.
The short circuit time t is the time during which the DC voltage Es is applied by the wound portion of the coated wire passing through the conductor. However, if the application of the DC voltage Es is not performed before the short circuit time t is short and the short circuit current i (t) reaches the threshold ir, the current, that is, the presence of a flaw can not be detected.

  In the example described in Patent Document 1, even if the applied voltage of direct current is 48 V, which is considerably large, it can not be reliably detected unless the length of the flaw is 10 mm or more. When the linear velocity of the coated wire is 5 m / sec, the time (short circuit time t) for a 10 mm long flaw to pass is 2 msec. If the applied voltage is reduced, even that can not be detected with certainty. Therefore, a flaw such as a short circuit time of 200 μsec (scratch length 1 mm) or 100 μsec (scratch length 0.5 mm) can not be detected.

Further, the inductance component L of the covered wire W in the bobbin B shown in FIG. 9 is large when a large amount of the covered wire W is wound and stored, and the covered wire W in the bobbin B is continued as the winding continues. Becomes smaller as As a result, the rising speed of the short circuit current i (t) shown in FIG. 10 is increased, and the short circuit time t at which the short circuit current i (t) can be detected is shortened, thereby reducing the size of the detectable flaw.
Therefore, depending on the amount of the covered wire in the bobbin, the size of the detectable flaw varies, and there is also a problem that the wound of the coated wire can not always be detected with the same accuracy in the winding process. In the case of application to a coil insertion device, the same problem occurs because the inductance component changes depending on the winding dose of the coil to be inserted.

  Furthermore, the conventional flaw detection apparatus for a coil only detects flaws in the coated electric wire forming the coil according to the detection accuracy of the apparatus, and can not measure or discriminate the size of the flaw. In spite of the amount of coated wire and the winding dose of the coil to be inserted, it was not possible to detect only a wound of a specified size or more.

  The present invention has been made to solve the above-mentioned problems, and enables detection of flaws in a coated wire forming a coil with accuracy even to a flaw smaller than that of a conventional flaw detection device. It is possible to measure or discriminate the size of the detected flaw without changing the size of the detectable flaw depending on the amount and the winding dose of the coil to be inserted, and to detect only the flaw of the designated size or more. With the goal.

The present invention is applied to a winding machine in which a coil is formed by a covered electric wire housed in a bobbin in order to achieve the above object, and an electric wire flaw detection device for detecting a wound of a covered electric wire forming a coil,
An alternating current is superimposed on an alternating voltage or direct current through a resistor for voltage generation between the end of the covered wire housed in the bobbin and the conductor with which the covered wire drawn from the bobbin contacts in the winding machine A power supply for applying a voltage, and a conduction check circuit for checking the conduction state of the coated wire from the voltage generated in the resistance.

Further, the present invention is a wire flaw detection device for detecting a flaw of a covered wire in the coil, which is applied to a coil insertion device in which a coil previously wound by a covered wire is inserted into a core,
An alternating current is superimposed on an alternating voltage or direct current through a resistor for voltage generation between one end of the covered wire forming the coil wound in advance and the conductor with which the covered wire contacts in the coil insertion device. And a power supply check circuit for checking a power supply state from the voltage generated in the resistor.

The alternating voltage superimposed on the alternating voltage or direct current is preferably a sine wave alternating voltage of 40 kHz to 60 kHz.
The conduction check circuit inputs and amplifies a voltage generated in the resistor, rectifies an output voltage of the input amplification unit, and rectifies, amplifies and shapes the waveform of the input amplification unit, and rectifies the voltage It is preferable to have a circuit that generates a flawed signal from the detection signal of the amplification and waveform shaping unit.

The circuit for generating the flawed signal includes a signal width check unit for outputting a pulse signal when the detection signal by the rectification, amplification and waveform shaping unit exceeds a signal width designated and designated, and the pulse signal for a desired signal. The signal processing unit may be configured to include a flawed signal output unit that performs expansion conversion on a pulse width signal and outputs the signal.
The signal width check unit applies a detection signal from the rectification, amplification, and waveform shaping unit to a common capacitor via any of a plurality of series circuits of a plurality of resistors having different resistances and a plurality of selection switches. It is preferable to comprise an integration circuit capable of selecting a time constant, and a circuit that outputs the pulse signal when the charging voltage of the capacitor reaches a threshold.

  The wire flaw detection device according to the present invention can accurately detect flaws on the coated wire of the coil up to smaller flaws than conventional flaw detection devices, and can detect flaws by the amount of the coated wire in the bobbin and the winding dose of the coil to be inserted. It is also possible to measure or determine the size of the detected flaw without changing the size of the mark, and to detect only flaws larger than the specified size.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows schematic structure of 1st Embodiment of the electric wire flaw detection apparatus by this invention applied to the winding machine. It is a block circuit diagram which shows the example of a concrete circuit configuration of the electric wire flaw detection apparatus shown in FIG. In the embodiment of FIG. 1, the copper wire of the part with a flaw in a covered wire | wire contacts the conductor of a winding machine, and it is a figure which shows an equivalent circuit in which the short circuit flows. It is a wave form diagram which shows the example of the voltage which superimposed alternating current on direct current | flow applied between the input terminal P and the earth terminal E in FIG.1 and FIG.2. It is a wave form diagram which shows the example of the short circuit time of the coated wire at the time of applying the voltage shown in FIG. 4, and the voltage which generate | occur | produces in the resistance 31. FIG. It is a wave form diagram which shows the example of the detection signal Pa by the rectification * amplification * waveform shaping part shown in FIG. FIG. 5 is a waveform diagram for explaining the function of a signal width check unit shown in FIG. 2; It is a figure which shows schematic structure of 2nd Embodiment of the electric wire flaw detection apparatus by this invention applied to the coil insertion apparatus. It is explanatory drawing of the equivalent circuit of the coated wire in the bobbin for demonstrating the conventional electric wire flaw detection apparatus, and its electricity supply circuit. It is a wave form diagram which shows the example of a waveform of the DC voltage applied at the time of the short circuit by the conventional wire flaw detection apparatus, and a short circuit current.

Hereinafter, a mode for carrying out the present invention will be specifically described based on the drawings.
First Embodiment
FIG. 1 is a view showing a schematic configuration of a first embodiment of a wire flaw detection device according to the present invention applied to a winding machine. In FIG. 1, 10 is a winding machine, 20 is a bobbin, 30 is a wire flaw detection device, and 40 is a controller for controlling the winding machine 1.

The winding machine 10 is a series winding machine, and includes a main body 11 and a wire guide cylinder 12 which protrudes upward from the main body 11 and has a winding nozzle 13 at its tip. In addition, a holder 14 is provided on the upper side surface of the main body 11, and the stator core 1 is held by the holder 14 so that the winding nozzle 13 can be inserted.
A bobbin 20 in which a large amount of covered electric wire is wound and stored is disposed outside the winding machine 10. The covered electric wire W is drawn out from the bobbin 20 and introduced into the main body 11 of the winding machine 10. It leads to the winding nozzle 13 from its lower end through the inside thereof and leads out from the tip of the winding nozzle 13.

The wire guide tube 12 is reciprocated in the axial direction as indicated by arrow A by a drive mechanism (not shown) and reciprocated by a predetermined angle as indicated by arrow B to turn the winding nozzle 13 into the stator core The coated electric wire W is wound around the inner teeth of 1 to form a coil 2.
In general, a plurality of bobbins 20 are disposed, and when the coated wire in one bobbin is used up, the next bobbin is switched to the next bobbin and the coated wire is drawn out and used.

The electric wire flaw detection device 30 includes a resistor 31 for current / voltage conversion, a DC power supply 32 and an AC power supply 33, and a conduction check circuit 34. The negative terminal of the DC power supply 32 is connected to the ground terminal E, the positive terminal is connected to one terminal of the resistor 31, and the other terminal of the resistor 31 is connected to the input terminal P via the AC power supply 33. In this embodiment, a capacitor for noise removal is connected in parallel to the resistor 31.
The conduction check circuit 34 checks the conduction state of the coated wire from the voltage generated between the two terminals when a current flows through the resistor 31. Thereby, the occurrence of a short circuit due to a wound of the coated wire is detected. The detected signal is output from the signal output terminal S and input to the controller 40.
The controller 40 is a control unit that controls the operation of the winding machine 10, and is connected to the winding machine 10 via the connectors 15 and 41 by a signal cable. The controller 40 also controls the on / off of the relay switch 25.

The end of the covered electric wire W housed in the bobbin 20 is connected to the input terminal P of the electric wire flaw detection device 30 through the relay switch 25, and the ground terminal E of the electric wire flaw detection device 30 is the main body of the winding machine 10 Ground with 11. The wire guide cylinder 12 and the winding nozzle 13 in the winding machine 10 and the respective members for guiding the coated wire W are all electrically connected to the main body 11 and grounded.
When the flaw detection of the coated wire by the wire flaw detection device 30 is started, the controller 40 turns on the relay switch 25 and causes the winding machine 10 to start the winding operation to the stator core 1.

  In the wire flaw detection device 30, the alternating current voltage from the alternating current power supply 33 is superimposed on the direct current voltage from the direct current power supply 32 and applied via the resistor 31 between the input terminal P and the ground terminal E. Therefore, between the end of the coated electric wire stored in the bobbin 20 and the conductor with which the coated electric wire W drawn out from the bobbin 20 contacts in the winding machine 10, an alternating current is made to direct current through the resistor 31 for voltage generation. The superimposed voltage is applied.

FIG. 2 is a block circuit diagram showing an example of a specific circuit configuration of the wire flaw detection device 30 shown in FIG. For example, the DC power supply 32 may be clamped at a constant voltage of about 4 V by a Zener diode from the control power supply of the apparatus.
The alternating current power supply 33 is an oscillation circuit that generates a sine wave alternating voltage having a peak value or an effective value of about 9 V at 50 kHz, for example.

The negative terminal of the DC power supply 32 is grounded, the positive terminal is connected to one end of a resistor 31 for current / voltage conversion, and the other end of the resistor 31 is connected to the input terminal P through an AC power supply 33. In parallel with the resistor 31, a capacitor C1 for noise removal is connected.
Then, when a current flows through the resistor 31, the conduction check circuit 34 that checks the conduction of the coated wire by the voltage generated at both ends includes the input amplification unit 341, the rectification / amplification / waveform shaping unit 342, and the signal width. A check unit 343 and a flawed signal output unit 344 are provided. The details will be described later along with their operation.

When the coating of the covered electric wire W is scratched in the winding and the copper wire comes in contact with the installed conductor, the resistance in the covered electric wire W shown in FIG. 1 and the electric wire scratching detection device 30 connected in series therewith. A closed circuit is formed by the DC power supply 31 and the DC power supply 32 and the AC power supply 33.
The closed circuit is shown as an equivalent circuit as shown in FIG. The covered electric wire W wound and stored in the bobbin 20 has, in addition to the resistance component R and the inductance component L, a capacitance component C (corresponding to a capacitor) parallel to its series circuit. This is due to the sum of stray capacitances generated between adjacent loops of coiled coated wire. The present invention is characterized in that an alternating current is supplied to the capacitor component, and the current is converted into a voltage by the resistor 31 and detected.

In the case of alternating current, it is difficult to flow an inductance, but it is easy to flow a capacity, and when an alternating voltage of a high frequency of several tens of kHz is applied, the phase advances by 90 ° but a current of almost the same waveform flows.
The current i (t) is converted into a voltage V (t) by the resistor 31 and detected. Thereby, when the linear velocity of the coated electric wire W is 5 m / sec, a flaw having a passing time of about 200 μsec, that is, a small flaw having a length of about 1 mm in the moving direction can be easily detected.
The switch SW in FIG. 3 assumes that the switch SW is turned on when the copper wire in the portion where the coated wire is damaged contacts the grounded conductor of the winding machine and short-circuits.

In this embodiment, the DC power supply 32 shown in FIGS. 1 to 3 outputs a DC voltage of 4 V, the AC power supply 33 is a sine wave having a frequency of 50 kHz (period is 20 μsec) and an AC voltage of ± 9 V peak value. Output The voltage of the waveform shown in FIG. 4 in which it is superimposed, that is, a sine wave AC voltage having an amplitude of 18 V around 4 V, is applied between the input terminal P and the ground terminal E. Thus, a relatively small voltage may be sufficient.
When the copper wire of the wound portion of the coated wire W comes into contact with the grounded conductor in the winding machine 10, the switch SW shown in FIG. 3 is turned on, and the AC component of the applied voltage is in the bobbin 20. And the short circuit current i (t) flows in the closed circuit shown in FIG.

Thereby, a voltage V (t) is generated between both terminals of the resistor 31. The voltage V (t) is V (t) = i (t) · R, where R is the resistance value of the resistor 31.
For example, when the short circuit time t is 200 μsec, as shown in FIG. 5, a 50 kHz sine wave AC voltage V (t) is generated over substantially the entire length of the short circuit time 200 μsec.
The waveform of the sinusoidal AC voltage V (t) is a state in which the amount of wire of the bobbin is large, the L component is large, and the C component is also large. Since the L component is large, only the AC component which has passed the C component can not pass the DC component. If the power supply is only direct current, a differential pulse of about 20 to 30 μsec that passes through the C component is generated at the rise of the short circuit signal, and the short circuit time t of 200 μsec can not be measured.
The sine wave AC voltage V (t) generated between both terminals of the resistor 31 is input to the input amplification unit 341 shown in FIG. 2 and amplified.

The configuration and function of each part of the conduction check circuit 34 shown in FIG. 2 will be described below.
The input amplification unit 341 is an amplification circuit using a transistor or an op amp. The output of the input amplification unit 341 is a sine wave alternating voltage signal having a waveform similar to the sine wave alternating voltage V (t) shown in FIG.
The AC voltage signal is input to the rectification / amplification / waveform shaping unit 342. The rectification / amplification / waveform shaping unit 342 is composed of diodes D1 and D2 for rectifying an alternating voltage signal to be input, a capacitor C2 for smoothing the rectified voltage, and an operational amplifier OP1 for amplifying and waveform shaping the output voltage. .

In the embodiment shown in FIG. 2, the input amplification unit 341 outputs an alternating current voltage signal (− side) obtained by inverting and amplifying the input sine wave alternating current voltage V (t) and an alternating current voltage signal (+ side) obtained by inverting the same. And is full-wave rectified by diodes D2 and D1 to charge and smooth capacitor C2.
The detection signal Pa of the rectification / amplification / waveform shaping unit 342 becomes a rectangular wave voltage signal of a predetermined wave height value Va as shown in FIG. 6, and the signal width corresponds to the short circuit time t according to the size of the flaw.
Note that depending on the configuration of the input amplification unit, a diode bridge circuit can be used as the full wave rectification circuit, and although the accuracy is reduced, it is also possible to use a half wave rectification circuit as the rectification circuit.

  The detection signal Pa is input to the signal width check unit 343, and a pulse signal Pb having a constant pulse width is output only when the detection signal Pa having a signal width exceeding the signal width designated and designated. The pulse signal is expanded and converted into a signal having a desired pulse width by a flawed signal output unit 344 and output as a flawed signal. The signal width check unit 343 and the flawed signal output unit 344 constitute a circuit that generates a flawed signal from the detection signal Pa of the rectification, amplification, and waveform shaping unit 342.

  The signal width check unit 343 in this embodiment is configured to detect the detection signal Pa of the rectification / amplification / waveform shaping unit 342 as the n of the plurality (n) of resistances R1 to Rn having different resistance values and the selection switches S1 to Sn. An integration circuit capable of selecting a time constant to be applied to a common capacitor C3 via any of the series circuits and a circuit for outputting the pulse signal Pb when the charge voltage of the capacitor C3 reaches a threshold value And an operational amplifier OP2.

The signal width check unit 343 selectively turns on any one of the selection switches S1 to Sn to select any one of the resistors R1 to Rn having different resistance values. Connected to form an integration circuit.
The charging voltage Vc of the capacitor C3 of the integrating circuit is Vc = Va (1−e− ^{t / τ 2} ), where Va is the peak value of the detection signal Pa input as shown in FIG. where t is the time from the start of application of the detection signal Pa, τ is a time constant, and when the capacitance of the capacitor C3 is C and the resistance value of the selected resistor is R, then τ = C · R.

Therefore, when the detection signal Pa is input to the signal width check unit 343, the charging voltage Vc of the capacitor C3 is faster at a faster speed as the time constant according to the resistance value of the selected resistor is smaller, as illustrated in FIG. The high value is raised to the voltage of Va, and the rising speed becomes slower as the time constant becomes larger.
Then, when the charging voltage Vc of the capacitor C3 reaches the set threshold value Vr, the operational amplifier OP2 outputs a pulse signal Pb having a constant pulse width.

In FIG. 7A, resistance R1 is selected so that when τ = C · R1 and detection signal Pa having a signal width of 100 μsec or more is input at this time, the resistance value of resistance R1 is output. Is set.
In FIG. 7, (b) shows the resistance value of the resistor R2 such that the resistor R2 is selected and τ = C · R2 so that the pulse signal Pb is output when the detection signal Pa having a signal width of 200 μsec or more is input at this time. Is set.

The resistance values of the resistors R3 to Rn are also set to values that change the time constant τ so that the operational amplifier OP2 outputs the pulse signal Pb when the detection signal Pa having a desired signal width or more is input.
As a result, if it is desired to detect a flaw in which the short circuit time is 100 μsec or more, only the selection switch S1 is turned on. If it is desired to detect a flaw in which the short circuit time is 200 μsec or more, only the selection switch S2 is turned on. The selection switches S1 to Sn can be switched and set in accordance with the size of the minimum scratch to be performed.
In this manner, the size of a flaw detected by the detection signal Pa can be measured or determined, and it is also possible to detect only flaws larger than the designated size.

  In this embodiment, an example of measuring the signal width (corresponding to the size of a flaw) of the detection signal Pa using a time constant circuit has been described, but using a counter, only while the detection signal Pa is high level The signal width can also be measured by counting clock pulses. In that case, it is also possible to output the pulse signal Pb for flaw detection only when the preset count value is reached.

Since the pulse width of the pulse signal Pb output from the signal width check unit 343 is normally short, such as msec or less, the pulse width (for example, 0. Extension conversion to a signal of 25 sec) and output from the signal output terminal S. The expansion conversion of the pulse width is performed by a pulse width conversion circuit 345 such as a monostable multivibrator or the like, the open collector transistor Q is controlled by its output signal, and is kept in the off state at all times. Output
Note that a voltage is applied to the collector of the transistor Q via a resistor, and the transistor Q is always turned off to output a high level signal, and when a flaw is detected, the transistor Q is turned on and a flawed signal is detected. As a low level signal may be output.

When the scratched signal is output from the scratched signal output unit 344 and is input to the controller 40, the controller 40 turns off the relay switch 25 to stop the detection of the scratch, and the winding operation of the winding machine 10 Stop. At this time, the controller 40 can operate an annunciator such as a buzzer or the like provided by itself or make an alarm by sound, or can visually notify by a display or a warning light.
Then, the stator in the winding and the coated wire in the winding machine 10 are removed, and a new stator core 1 is set in the winding machine 10, and a new portion of the coated wire is drawn out from the bobbin 20 and prepared. Resume the winding.

According to the electric wire flaw detection device 30, the size of the flaw that can be detected can be measured or determined without changing the size of the flaw that can be detected depending on the amount of the covered electric wire in the bobbin 20, and the flaw of the designated size or larger It is also possible to detect only
The description of the configuration and function of the electric wire flaw detection device 30 according to this embodiment is as described above, but a changeable example will be described.

  Although the power supply which applies the voltage which superimposed alternating current on direct current was used as a power supply, it can implement only with alternating current power supply. However, applying a voltage in which alternating current is superimposed on direct current results in a case where the damage is large and the short circuit time is long, or the coated wire in the bobbin 20 is reduced and both the capacitive component and the reactive component are reduced. More stable detection is possible.

The AC voltage is preferably sinusoidal, but it can not be used even with triangular or rectangular AC. The frequency is preferably a relatively high frequency alternating current of about 50 kHz, but depending on the application, a slightly lower frequency alternating current may be used. In the case of 50 kHz, since one cycle is 20 μsec, an error of up to 10 μsec (half cycle) may occur when the detection voltage is full-wave rectified.
Although the winding machine 10 has been described as a direct winding machine winding directly on the stator core of a motor or dynamo, the above-described wire flaw detection device 30 directly on the core of an electromagnetic device such as a rotor core of a motor or dynamo or a transformer. The same applies to a wound series winding. Moreover, it is applicable also to the winding machine which forms beforehand the coil inserted in those cores, or the winding machine which forms a coreless coil. Furthermore, not limited to rotating electric machines such as motors and dynamos, the same can be applied to the formation of coils of non-rotating electric machines such as linear motors and transformers.

Second Embodiment
Next, a second embodiment of the present invention will be described.
FIG. 8 is a view showing a schematic configuration of a second embodiment of a wire flaw detection device for coils according to the present invention applied to a coil insertion device, in which the parts corresponding to the respective parts in FIG. Yes, their explanations are omitted. The conduction check circuit 34 is also similar to the example described with reference to FIG.
The electric wire flaw detection device 30 of this second embodiment also has the same configuration and function as those of the first embodiment, but one end of the covered electric wire forming the coil 4 inserted into the core by the coil insertion device 50 , And is connected to the input terminal P via the relay switch 25.

In the coil insertion device 50, the stator core 3 is held by a holder (not shown) provided in the main body 51, and the blades 52 are annularly arranged corresponding to the internal teeth thereof. A wedge guide 53 is disposed outside the blade 52 to constitute a coil insertion jig 54.
A stripper 55 is provided inside the blade 52 so as to be vertically movable by a drive shaft 56. Reference numeral 57 denotes a connector for connecting to the controller 40.

  Then, the coil 4 wound in advance is inserted and held in the predetermined gap of the blade 52, and the stripper 55 is pushed up by the drive shaft 56 to insert the coil 4 in the predetermined gap of the slot of the stator core 3 Do. At this time, a not-shown wedge (insulation material) is inserted into the opening inner periphery of the slot of the stator core 3 through the gap of the wedge guide 53.

The main body 51 of the coil insertion device 50 and the respective parts made of a conductor in contact with the coil 4 provided therein and the stator core 3 are both grounded.
When the coil 4 is pushed up by the stripper 55 and is inserted into a predetermined gap of the slot of the stator core 3, the copper wire may be damaged if it is scratched or the coated electric wire forming the coil 4 is originally damaged. Short-circuit any of the grounded conductors.
At that time, an alternating current flows to the resistor 31 of the wire flaw detection device 30 through the capacitive component of the coil 4, thereby generating an alternating voltage between the terminals of the resistor 31. When a flaw of a desired size or more is detected, a flaw presence signal is output.

Also in this embodiment, the wound of the coated wire forming the coil can be accurately detected to a small wound with a relatively small voltage, and the size of the detected wound does not change depending on the winding dose of the coil inserted. The size can be measured or determined, and it is also possible to detect only flaws larger than the designated size.
In this example, the case where the wire flaw detection device 30 is applied to the coil insertion device 50 for inserting the coil 4 into the stator core 3 has been described, but in the coil insertion device for inserting a coil into the core of various electromagnetic devices such as a rotor core or transformer. Also, the wire flaw detection device 30 of this embodiment can be applied similarly.

  As mentioned above, although various embodiments of this invention have been described, in the range which fulfills the matter specified to each claim of a claim, as for these composition, the composition of each embodiment is suitably changed, added or omitted , Can be combined.

1, 3: Stator core 2, 4: Coil
10: Winding machine 11: Winding machine body 12: Electric wire guide cylinder 13: Winding nozzle
14: Holder 15: Connector of winding machine 20: Bobbin 25: Relay switch 30: Wire flaw detector 31: Resistance for current / voltage conversion 32: DC power supply
33: AC power supply 34: conduction check circuit 40: controller 41: connector 50: coil insertion device 51: main body of coil insertion device 52: blade
53: Wedge guide 54: Coil insertion jig 55: Stripper 56: Drive shaft 57: Connector of coil insertion device 341: Input amplification unit
342: Rectification, amplification, waveform shaping unit 343: Signal width check unit
344: Scratched signal output unit 345: Pulse width conversion circuit W: Coated wire P: Input terminal E: Ground terminal S: Signal output terminal

The present invention is applied to a winding machine in which a coil is formed by a covered electric wire housed in a bobbin in order to achieve the above object, and an electric wire flaw detection device for detecting a wound of a covered electric wire forming a coil,
Between a DC power supply outputting a DC voltage, an AC power supply outputting an AC voltage, the end of the coated wire housed in the bobbin and a conductor with which the coated wire drawn from the bobbin contacts in the winding machine , by connecting the resistor and the DC power supply and the AC power supply for the current-voltage conversion in series, a circuit for applying a voltage obtained by superimposing the AC voltage to the DC voltage, the coating from the voltage generated in the resistor And a conduction check circuit for checking the conduction state of the electric wire.

Further, the present invention is a wire flaw detection device for detecting a flaw of a covered wire in the coil, which is applied to a coil insertion device in which a coil previously wound by a covered wire is inserted into a core,
Between a DC power supply outputting a DC voltage, an AC power supply outputting an AC voltage , one end of a coated wire forming the coil wound in advance, and a conductor with which the coated wire contacts in the coil insertion device in, by connecting the resistor and the DC power supply and the AC power supply for the current-voltage conversion in series, a circuit for applying a voltage obtained by superimposing the AC voltage to the DC voltage, current from the voltage generated in the resistor And a conduction check circuit for checking the situation.

Preferably , the alternating voltage is a sinusoidal alternating voltage with a frequency of 50 kHz .
The conduction check circuit inputs and amplifies a voltage generated in the resistor, rectifies an output voltage of the input amplification unit, and rectifies, amplifies and shapes the waveform of the input amplification unit, and rectifies the voltage It is preferable to have a circuit that generates a flawed signal from the detection signal of the amplification and waveform shaping unit.

The electric wire flaw detection device 30 connects a resistor 31 for current / voltage conversion, a DC power supply 32 and an AC power supply 33 in series between the DC power supply 32 and the AC power supply 33, and the input terminal P and the earth terminal E. A circuit for applying an AC voltage from the AC power supply 33 superimposed on a DC voltage from the DC power supply 32 and a conduction check circuit 34 are provided. The negative terminal of the DC power supply 32 is connected to the ground terminal E, the positive terminal is connected to one terminal of the resistor 31, and the other terminal of the resistor 31 is connected to the input terminal P via the AC power supply 33. In this embodiment, a capacitor for noise removal is connected in parallel to the resistor 31.
The conduction check circuit 34 checks the conduction state of the coated wire from the voltage generated between the two terminals when a current flows through the resistor 31. Thereby, the occurrence of a short circuit due to a wound of the coated wire is detected. The detected signal is output from the signal output terminal S and input to the controller 40.
The controller 40 is a control unit that controls the operation of the winding machine 10, and is connected to the winding machine 10 via the connectors 15 and 41 by a signal cable. The controller 40 also controls the on / off of the relay switch 25.

Since so as to apply a voltage obtained by superposing an AC voltage by an AC power source into a DC voltage by a DC power source between the input terminal and the ground terminal, as compared to applying only by the AC voltage AC power supply, large scratches More stable detection is possible when the short circuit time is long or when the number of coated wires in the bobbin 20 is reduced and both of the capacitive component and the reactance component are reduced.

The AC voltage is preferably sinusoidal, but it can not be used even with triangular or rectangular AC. The frequency is preferably a relatively high frequency alternating current of about 50 kHz, but depending on the application it may be a somewhat lower or higher frequency , 40 kHz to 60 kHz alternating current. In the case of 50 kHz, since one cycle is 20 μsec, an error of up to 10 μsec (half cycle) may occur when the detection voltage is full-wave rectified.
Although the winding machine 10 has been described as a direct winding machine winding directly on the stator core of a motor or dynamo, the above-described wire flaw detection device 30 directly on the core of an electromagnetic device such as a rotor core of a motor or dynamo or a transformer. The same applies to a wound series winding. Moreover, it is applicable also to the winding machine which forms beforehand the coil inserted in those cores, or the winding machine which forms a coreless coil. Furthermore, not limited to rotating electric machines such as motors and dynamos, the same can be applied to the formation of coils of non-rotating electric machines such as linear motors and transformers.

Claims (6)

An electric wire flaw detection device which is applied to a winding machine which forms a coil by a covered electric wire accommodated in a bobbin and which detects a flaw of a covered electric wire which forms the coil,
An alternating current is superimposed on an alternating voltage or direct current through a resistor for voltage generation between the end of the covered wire housed in the bobbin and the conductor with which the covered wire drawn from the bobbin contacts in the winding machine A power supply that applies a voltage,
An electric wire flaw detection device comprising: a conduction check circuit for checking the conduction state of the coated electric wire from the voltage generated in the resistance. A wire flaw detection device for detecting a flaw of a covered wire in the coil, which is applied to a coil insertion device in which a coil prewound by a covered wire is inserted into a core,
An alternating current is superimposed on an alternating voltage or direct current through a resistance for voltage generation between one end of the covered wire forming the coil wound in advance and the conductor with which the covered wire contacts in the coil insertion device. A power supply that applies a
An electric wire flaw detection device comprising: a conduction check circuit for checking the conduction state of the coated electric wire from the voltage generated in the resistance.   The wire flaw detection device according to claim 1, wherein the alternating voltage superimposed on the alternating voltage or direct current is a sine wave alternating voltage of 40 kHz to 60 kHz.   The conduction check circuit inputs and amplifies a voltage generated in the resistor, an output voltage of the input amplification unit is rectified, and a rectification, amplification, and waveform shaping unit performs amplification and waveform shaping, and the rectification The wire flaw detection device according to any one of claims 1 to 3, further comprising: a circuit that generates a flawed signal from a detection signal of the amplification and waveform shaping unit.   A circuit for generating the scratched signal, a signal width check unit for outputting a pulse signal when a detection signal by the rectification, amplification and waveform shaping unit exceeds a signal width designated and specified; and the pulse signal desired 5. The wire flaw detection device according to claim 4, further comprising: a flawed signal output unit which performs expansion conversion on a pulse width signal and outputs the signal.   The signal width check unit applies a detection signal from the rectification, amplification, and waveform shaping unit to a common capacitor via any of a plurality of series circuits of a plurality of resistors having different resistances and a plurality of selection switches. 6. The wire flaw detection device according to claim 5, comprising: an integration circuit capable of selecting a time constant; and a circuit that outputs the pulse signal when a charging voltage of the capacitor reaches a threshold.

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