Motor

Abstract

To stably supply a detection signal of a detector such as an encoder for detecting the movement of a motor to a driver side without using a communication cable.SOLUTION: A motor to which electric power is supplied from an external driver via a power line includes an input unit to which a drive current is input from the driver via the power line, a winding unit connected to the input unit inside the motor and having a plurality of phases, and a processing unit that applies a detection signal from a detector that detects movement of a drive shaft of the motor to at least two phases among the plurality of phases of the winding unit or at least two interphases among a plurality of interphases in the winding unit as a signal in a predetermined format so that the detection signal can be extracted on a driver side.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a motor. [Background technology]

[0002] For motors used to drive loads for various purposes, it is necessary to grasp the motor's state in order to accurately control it, and a detection device such as an encoder is generally used to do this. To drive an encoder, power must be supplied. Generally, a servo system (e.g., a driver) and the encoder are connected by a cable, and power is supplied via the cable. Alternatively, Patent Document 1 discloses a configuration in which power is supplied to the encoder from a power supply configured differently from the servo system. Specifically, Patent Document 1 discloses an auxiliary power supply for the encoder that operates when the power supplied to the encoder from the system drops for some reason.

[0003] Furthermore, detection signals relating to the position and speed of the motor detected by the encoder must be transmitted to the servo system for motor control. Generally, these signals are transmitted via a communication cable connecting the servo system and the encoder. This communication cable may be formed integrally with the cable for supplying power. Patent documents 2 and 3 disclose other modes for transmitting and receiving signals between the servo system and the encoder, in which the servo system and the encoder communicate wirelessly. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 8-251817 [Patent Document 2] Japanese Patent Application Laid-Open No. 2001-297389 [Patent Document 3] Japanese Patent Application Laid-Open No. 2002-197581 Summary of the Invention [Problem to be solved by the invention]

[0005] To achieve precise control, such as servo control of a motor, an encoder is required to detect motor movement, and the detection signal related to the detected motor movement must be provided to a driver that performs servo control. In other words, for proper servo control of the motor, stable communication between the encoder and the driver must be ensured. Generally, a stable communication environment is ensured by connecting the encoder and driver with a cable, but this requires wiring a cable related to the encoder, which can increase the wiring workload and increase costs due to the cable.

[0006] Furthermore, while technologies for connecting a driver and an encoder so that they can communicate wirelessly have been proposed, it is not easy to implement them in practical situations. Generally, a motor is the power source for the drive shaft of an equipment, and is therefore built into the equipment. Therefore, even if an encoder and a driver attempt to communicate wirelessly, there is a certain distance between the wireless transmitting equipment (antenna) and the encoder, which can significantly reduce the stability of communication compared to wired communication. Furthermore, if the equipment itself is a mobile device such as a robot, there is a risk that wireless communication may be obstructed by obstacles, or that wireless communication may not be optimal depending on the position or posture of the equipment.

[0007] The present invention has been made in view of such problems, and provides a system for stably supplying a detection signal from a detector such as an encoder that detects the movement of a motor to the driver side without using a communication cable. The purpose is to provide technology. [Means for solving the problem]

[0008] A motor according to one aspect of the present invention is a motor that receives power from an external driver via a power line. The motor includes: an input unit that receives a drive current from the driver via the power line; a winding unit connected to the input unit and having multiple phases; and a processing unit that applies, to at least two of the multiple phases of the winding unit or to at least two of the multiple phases of the winding unit, a detection signal from a detector that detects the movement of the motor's drive shaft as a signal in a predetermined format so that the detection signal can be extracted on the driver side. The motor may be a single-phase AC motor or a three-phase AC motor. The winding coils of the motor may be connected in a delta connection or a star connection (or a Y connection). The winding coils of the winding unit may be wound around the stator of the motor in a distributed or concentrated winding manner. In other words, the motor of the present invention does not intend to impose any particular restrictions on the specific configuration of the winding unit. Furthermore, the detector may be, for example, a so-called encoder, but is not limited to this, and other sensors capable of detecting the movement of the drive shaft of the motor (for example, a vibration sensor, etc.) may also be used.

[0009] By adopting such a configuration, the detection signal of the detector is applied to the drive current flowing through the windings inside the motor and transmitted to the driver side via the windings and the power lines connected thereto. Furthermore, the detection signal is applied as a signal in a predetermined format that allows the driver side to extract the detection signal. For example, the predetermined format signal can be a signal that has electrical characteristics (e.g., frequency, amplitude, etc.) that are physically distinguishable from the drive current flowing through the windings to which the detection signal is applied.

[0010] As a result, the detection signal can be more reliably delivered to the driver via a power line physically connected to the driver. This allows for more stable delivery of the detection signal to the driver regardless of the motor's position or orientation, compared to wireless transmission of the detection signal. Furthermore, using the power line to transmit the detection signal eliminates the need for a communication cable, reducing the work and costs required for wiring. Furthermore, the motor described above is configured to apply the detection signal to at least two of the multiple phases of the winding, or between at least two of the multiple phases in the winding, thereby providing redundancy in the transmission of the detection signal to the driver. This ensures stable transmission of the detection signal via the winding and power line, significantly contributing to the stability of motor servo control based on the detection signal from a detector such as an encoder.

[0011] More preferably, in the motor, the processing unit may apply the detection signal as the predetermined format to all of the multiple phases of the winding unit or to all of the multiple inter-phase connections in the winding unit. By applying the detection signal to all phases or all inter-phase connections in this manner, redundancy in transmission of the detection signal to the driver can be maximized, and thus the stability of servo control of the motor can also be maximized.

[0012] Here, in the motor described above, a transformer structure including a primary coil connected to each phase of the winding section or between each phase in the winding section, and a secondary coil corresponding to the primary coil may be arranged, and the processing unit may be configured to apply the detection signal to the secondary coil corresponding to each phase of the winding section or between each phase. In this case, in the motor, the processing unit applies the detection signal using the transformer structure arranged for the winding section of the motor. Here, the transformer structure is formed within the motor so that a portion of the drive current, which is an AC current flowing through the winding section, is input to the primary coil side. The transformer structure may be either an auto-winding transformer or a compound-winding transformer. In the case of an auto-winding transformer, The secondary coil refers to a portion of the primary coil that is shared by both. Generally, when a coil is wound around the stator core of a motor, a certain height of the coil protrudes from the stator core at the coil end, so a transformer structure can be formed around the winding portion at that coil end. Alternatively, a secondary coil of a transformer structure can also be wound in the space where the coil is wound around the stator core. Then, when the processing unit applies a detection signal to the secondary coil, a signal corresponding to the detection signal is superimposed on the drive current flowing through the primary coil and sent to the driver.

[0013] In the motor described above, the processing unit may apply the detection signal to each phase of the winding unit or between each phase via an insulating unit that insulates the voltage applied to the winding unit. Applying the detection signal via an insulating unit in this manner prevents the influence of high voltage associated with the drive current on the motor side from reaching a detector such as an encoder, thereby enabling stable transmission of the detection signal.

[0014] In the motor described above, the processing unit may be configured to apply the detection signal as a signal of the predetermined format having a fundamental frequency that does not overlap with a predetermined frequency related to the drive of the motor by the driver. The processing unit may then vary the fundamental frequency in response to fluctuations in the predetermined frequency. Note that if the predetermined frequency does not fluctuate or if the fluctuation is extremely small, it is not necessary to vary the fundamental frequency. In this way, for the signal of the predetermined format related to the application of the detection signal by the processing unit, by focusing on a predetermined frequency related to the drive of the motor and setting the fundamental frequency to a frequency that does not overlap with the predetermined frequency, extraction of the detection signal on the driver side can be achieved in a state that is less affected by the drive of the motor.

[0015] An example of the predetermined frequency may be the PWM frequency of the driver corresponding to the rotation speed of the motor, or a higher-order frequency of the PWM frequency. Alternatively, the predetermined frequency may be a resonance frequency associated with the load driven by the motor. Furthermore, a frequency related to the drive of the motor in other forms may also be the predetermined frequency.

[0016] In the motor described above, the processing unit outputs the detection signal at an amplitude that is a predetermined time or more larger than the amplitude of the drive current corresponding to a higher-order frequency of the PWM frequency of the driver. The predetermined multiplication factor may be applied as a signal of the predetermined format having the following formula: The predetermined multiplication factor is a parameter that defines the scale of the detection signal to such an extent that the detection signal can be stably distinguished when the amplitude of the motor drive current and the amplitude of the detection signal are compared when the detection signal is extracted by the driver. Therefore, the value of the predetermined multiplication factor can be determined taking into consideration the extraction accuracy of the detection signal by the driver.

[0017] In the motor described above, the processing unit may be further configured to extract a portion of the power generated by the drive current input to the windings via the input unit and supply the extracted power to the detector. With this configuration, the transmission of the detector's detection signal and the supply of power to the detector are achieved via the motor's windings and power lines, making it possible to eliminate the need for cables for both transmission and power supply. [Effects of the Invention]

[0018] A detection signal from a detector such as an encoder that detects the movement of the motor can be stably supplied to the driver side without using a communication cable. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a control system that controls the drive of a motor. [Figure 2] FIG. 2 is a diagram illustrating a schematic configuration of a motor. [Figure 3] FIG. 1 is a first diagram schematically illustrating the arrangement of a winding section of a motor and a transformer structure provided for the winding section. [Figure 4] 10A and 10B are diagrams illustrating the fundamental frequency of a detection signal applied via a transformer structure provided in a winding portion. [Figure 5] 10 is a flowchart showing a flow for determining the fundamental frequency of a detection signal applied via a transformer structure provided in a winding portion. [Figure 6] FIG. 2 is a second diagram schematically illustrating the arrangement of the windings of the motor and the transformer structure provided for the windings. [Figure 7] FIG. 3 is a third diagram schematically illustrating the arrangement of the windings of the motor and the transformer structure provided for the windings. [Figure 8] FIG. 4 is a fourth diagram schematically illustrating the arrangement of the windings of the motor and the transformer structure provided for the windings. [Figure 9] FIG. 5 is a fifth diagram schematically illustrating the arrangement of the windings of the motor and the transformer structure provided for the windings. DETAILED DESCRIPTION OF THE INVENTION

[0020] Example 1 FIG. 1 is a diagram showing the schematic configuration of a control system that controls the drive of a motor. First, the control system will be described. The control system is a PLC (Programmable Logic Controller) PLC 5 is connected to network 1 as a host controller. A plurality of servo drivers 4 are connected to network 1, and are configured to be able to send and receive signals to and from PLC 5. Note that while FIG. 1 shows a detailed functional configuration of one servo driver 4 as a representative example, the other servo drivers 4a and 4b also have functional configurations equivalent to that of servo driver 4. Motor 2 is connected to servo driver 4 via power line 11 and receives a supply of driving power. Similarly, motors 2a and 2b receive a supply of driving power from servo drivers 4a and 4b via power lines 11a and 11b, respectively. Hereinafter, the structures of the motors and servo drivers will be described representatively based on motor 2 and servo driver 4.

[0021] Here, the motor 2 is driven and controlled according to commands from the PLC 5 to drive a predetermined load device. As an example, the load device may be various mechanical devices (e.g., an arm of an industrial robot or a conveying device), and the motor 2 is incorporated into the device as an actuator for driving the load device. The motor 2 is an AC servo motor. Alternatively, the motor 2 may be an induction motor or a DC motor. The motor 2 includes a motor body 21 having a stator including a winding formed by a coil wound around a stator core and a rotor incorporating a permanent magnet, and an encoder 22 having a detection disk that rotates in conjunction with the rotation of the rotor and can detect the rotation state of the rotor. The rotation detection by the encoder 22 may be an incremental method or an absolute method.

[0022] The detection signal from the encoder 22 is transmitted to the servo driver 4 via the power line 11 to a communication unit 42 of the servo driver 4, which will be described later. The transmitted detection signal is used for servo control in a control unit 41 of the servo driver 4, which will also be described later. The detection signal from the encoder 22 includes, for example, position information about the rotational position (angle) of the rotating shaft of the motor 2, information about the rotational speed of the rotating shaft, etc.

[0023] Here, the servo driver 4 has a control unit 41, a communication unit 42, and a power conversion unit 43. The control unit 41 is a functional unit that controls the servo control of the motor 2 based on commands from the PLC 5. The control unit 41 receives an operation command signal related to the operation (motion) of the motor 2 from the PLC 5 via the network 1 and a detection signal transmitted from the encoder 22, and performs servo control related to the drive of the motor 2, i.e., calculates a command value related to the operation of the motor 2. The servo driver 4 controls the motor 2 in addition to the servo control of the motor 2. The servo driver 4 controls the motor 2 in addition to the servo control of the motor 2. The control unit 41 ...

[0024] The communication unit 42 is a functional unit that controls communication between the encoder 22 and the servo driver 4, i.e., communication related to the detection signal of the encoder 22. In this embodiment, the detection signal of the encoder 22 is transmitted to the communication unit 42 via the power line 11, the details of which will be described later. The power conversion unit 43 supplies drive power to the motor 2 via the power line 11 based on a command value related to the operation of the motor 2 calculated by the control unit 41. The AC power sent from the AC power supply 7 to the servo driver 4 is used to generate this supply power. In this embodiment, the servo driver 4 is of a type that receives three-phase AC, but it may also be of a type that receives single-phase AC. Alternatively, the servo driver 4 may be of a type that receives DC.

[0025] Next, the schematic configuration of the motor 2 will be described with reference to FIG. 2. The motor 2 is a three-phase (U-phase, V-phase, and W-phase) AC motor and includes a motor body 21 and an encoder 22. The motor body 21 includes a rotor 212 and a stator 213. A permanent magnet is incorporated into the rotor 212 and rotatably supported therein. The stator 213 includes a stator core formed of electromagnetic steel sheets, on which coils are wound, forming a winding section 25. In this embodiment, the connection of each phase in the winding section 25 is a Y connection, but a delta connection may also be used instead. In this embodiment, the coils may be wound around the stator core using either distributed winding or concentrated winding. The configuration shown in FIG. 2 is merely schematic, and the technical concept of the present invention can be applied regardless of the specific configuration of the motor.

[0026] The power line 11 for supplying drive power from the servo driver 4 is connected to a connector 211. The connector 211 corresponds to an input unit of the present invention. The connector 211 is connected to each phase of the winding unit 25. In the motor 2, a transformer structure (see 53, 63, 73, and 80 shown in FIG. 3 and elsewhere; details will be described later) is disposed for the winding unit 25, and a processing unit 214 is provided that uses the transformer structure to perform predetermined electrical processing on the drive current of the motor 2 flowing through the winding unit 25. The transformer structure of the processing unit 214 enables electrical signals to be exchanged between the primary coil side and the secondary coil side while maintaining insulation between the winding unit 25 and the encoder 22 side. Specifically, the processing unit 214 performs a first process of applying a detection signal from the encoder 22 to the drive current of the motor 2 flowing through the winding unit 25, and a second process of extracting a portion of the power resulting from the drive current of the motor flowing through the winding unit 25 to be used as drive power for the encoder 22. Transformer structures 53, 63, and 73 shown in Figure 3 and other figures are transformer structures for performing the first process, and transformer structure 80 is a transformer structure for performing the second process. Note that although the transformer structure for the second process shown in Figure 3 and other figures is for one phase, transformer structures for the second process having the same function may be installed for two or three phases.

[0027] 3, 6, and 8, transformer structures 53, 63, 73, and 80 are formed on winding portion 25 at the coil end of stator 213. In addition, in the embodiment shown in Fig. 9, the transformer structures are formed by winding the primary coils of transformer structures 53, 63, and 73 around the stator core together with the coil of winding portion 25 wound around the stator core, and transformer structure 80 is formed on winding portion 25 at the coil end of stator 213 in the same manner as in Fig. 3, etc. For the transformer structure, a form other than these forms may be adopted.

[0028] Here, a description will be given of the first process using the transformer structures 53, 63, and 73. The encoder 22 has a detection unit 221 that detects the rotation state of the motor, and the signal detected thereby is is referred to as a detection signal. Specific examples of the detection signal may include signals related to the position and speed of the motor, as well as signals related to acceleration and vibration obtained by processing these signals. When the detection signal is applied from the detector 221 of the encoder 22 to the drive current flowing through the winding 25 and transmitted to the servo driver 4 via the power line 11, the detection signal is passed as a current containing a signal in a predetermined format to the secondary coils of the transformer structures 53, 63, and 73 of the processor 214. This allows the processor 214 to generate a current corresponding to the detection signal in the primary coil of each transformer structure and pass it through the coil of the winding 25. In this case, the processor 214 may perform a predetermined amplification process on the detection signal. This amplification process can improve the noise resistance of the detection signal. The coil of the winding 25 is electrically connected to the servo driver 4 via the power line 11, allowing the encoder 22 to transmit the detection signal to the servo driver 4.

[0029] Here, the above-mentioned predetermined format for applying the detection signal will be explained. The predetermined format is a format related to the characteristics of the electrical signal, which is set so that the detection signal applied via each transformer structure can be extracted and separated from the drive current on the servo driver 4 side. Specifically, the predetermined format is a format that determines the frequency, amplitude, etc. of the electrical signal. Details of the predetermined format will be explained later with reference to FIG. 5.

[0030] Furthermore, in this embodiment, the first process may include a process of transmitting a predetermined signal from the servo driver 4 to the encoder 22 via the power line 11 and the winding unit 25. In this case, a current with a predetermined signal superimposed on the coil of the winding unit 25 is caused to flow from the servo driver 4 side, and the current flows through the primary coil side of the transformer structure, so that the processing unit 214 can generate a current corresponding to the predetermined signal on the secondary coil side of the transformer structure. Then, the generated signal is passed to the encoder 22.

[0031] Next, a second process using the transformer structure 80 will be described. In the second process, the processing unit 214 extracts power from the AC current output from the secondary coil of the transformer structure 80 as power for the encoder 22. The power is then rectified by the supply unit 215, and if necessary, a DC-DC converter included in the supply unit 215 increases or decreases the voltage to a DC voltage suitable for driving the encoder 22. The supply unit 215 is electrically connected to the encoder 22 so that it can supply DC power to the encoder 22 when the encoder 22 is attached to the motor main body 21. The supply unit 215 may also have a secondary battery that can store the rectified DC power. In this case, power can be supplied to the encoder 22 even during periods when no drive current flows through the winding unit 25 or when the drive current is extremely low.

[0032] (First form) Next, a first embodiment of the winding section 25 of the motor body 21 and the arrangement of the transformer structure provided for the winding section 25 will be illustrated. First, the first embodiment will be described with reference to FIG. 3. The winding section 25 includes winding sections L5, L6, and L7 for three phases: U, V, and W. The winding sections for each phase are connected in a Y-connection, with the junction of each winding section serving as a neutral point. For the U-phase winding section L5, in FIG. 3, its inductance component is indicated by 51 and its resistance component is indicated by 52. ​​Similarly, for the V-phase winding section L6, its inductance component is indicated by 61 and its resistance component is indicated by 62. Furthermore, for the W-phase winding section L7, its inductance component is indicated by 71 and its resistance component is indicated by 72.

[0033] A transformer structure forming the processing section 214 is arranged in each phase. Specifically, the transformer structures 53, 63, and 73 are arranged as transformer structures for the first processing. In the U phase, the primary coil 531 of the U phase transformer structure 53 is connected in series to the winding section L5, and in the V phase, one coil of the V phase transformer structure 63 is connected in series to the winding section L6. In the W-phase, the primary coil 731 of the W-phase transformer structure 73 is connected in series to the winding portion L7. The secondary coil 532 of the U-phase transformer structure 53, the secondary coil 632 of the V-phase transformer structure 63, and the secondary coil 732 of the W-phase transformer structure 73 are connected to the encoder 22.

[0034] Furthermore, the processing unit 214 is provided with a transformer structure 80 as a transformer structure for the second processing. The transformer structure 80 is connected only to the U phase. Specifically, A primary coil 801 of the transformer arrangement 80 is connected in series to the primary coil 531 of the transformer arrangement 53. A secondary coil 802 of the transformer arrangement 80 is connected to the supply 215.

[0035] In this way, by arranging the transformer structure for the first processing in each of the U, V, and W phases, the encoder This allows redundancy in the transmission of the detection signal from the encoder 22. As a result, the possibility that the servo driver 4, to which the detection signal is sent, will fail to receive the detection signal from the encoder 22 is greatly reduced, thereby enabling stable and continuous servo control of the motor 2. Furthermore, since a transformer structure 80 for the second processing is also provided, the driving power for the encoder 22 is supplied via the winding portion 25 of the motor 2. Therefore, the encoder 22 does not require a cable for transmitting the detection signal or a cable for supplying driving power, thereby significantly reducing the cabling work and reducing the cost when installing the motor 2 in a system.

[0036] The winding ratio (the ratio of the number of windings of the secondary coil to the number of windings of the primary coil) of the transformer structure of each phase is basically the same, but may be different. In the embodiment shown in Fig. 3, a transformer structure for the first processing is provided for all three phases, but it may be provided for only two of the three phases. By providing a transformer structure for the first processing for at least two phases, redundancy in the transmission of the detection signal can be maintained.

[0037] Here, the point of applying the detection signal of the encoder 22 as a signal of a predetermined format to the secondary coil side of the transformer structure 53, 63, 73 of the processing unit 214 will be described in detail with reference to Figs. 4 and 5. Fig. 4 shows the amplitude spectrum of the frequency components contained in the drive current flowing through the winding unit 25 of the motor 2. The horizontal axis of the graph shown in Fig. 4 represents frequency, and the vertical axis represents normalized amplitude. Here, the frequency f0 in Fig. 4 is the PWM frequency of the servo driver 4. and the amplitude of the frequency f0 is the largest. In Fig. 4, the frequency f0 is used as the reference and the higher frequency components can be recognized.

[0038] The frequency components contained in the drive current flowing through winding portion 25 also include frequencies related to the rotational speed (electrical angular frequency) of motor 2. These frequencies change depending on the rotational speed of motor 2. Furthermore, when a predetermined load (such as a robot arm) is driven by motor 2, if the resonant frequency of that load exists within the driving range of motor 2, the effect of the resonant frequency may appear as frequency components contained in the drive current.

[0039] Considering that the drive current flowing through the winding portion 25 contains multiple frequency components related to the drive of the motor 2, a predetermined format for the detection signal of the encoder 22 is determined. Here, if the multiple frequency components contained in the drive current are defined as the predetermined frequencies, the PWM frequency of the servo driver 4 corresponding to the rotational speed of the motor 2 and higher-order frequencies of the PWM frequency are defined as the predetermined frequencies, and a fundamental frequency that does not overlap with the predetermined frequencies is adopted as the predetermined format (see frequency f10 in FIG. 4). That is, the detection signal of the encoder 22 is applied to the secondary coils of the transformer structures 53, 63, and 73 so that the detection signal is a signal of the fundamental frequency. The detection signal applied as a signal of the predetermined format is delivered to the servo driver 4 via the power line 11. Because the frequency of the detection signal does not overlap with the predetermined frequency, the servo driver 4 can extract the detection signal appropriately. The frequency (fundamental frequency) of the predetermined signal applied to the secondary coils of the transformer structures 53, 63, and 73 may be changed depending on each transformer structure. For example, the fundamental frequency corresponding to the transformer structure 53 may be f10, the fundamental frequency corresponding to the transformer structure 63 may be f11, and the fundamental frequency corresponding to the transformer structure 73 may be f12. This ensures that the detection signal is delivered to the servo driver 4 via the power line 11 more reliably.

[0040] Secondly, the predetermined format may be set to the resonant frequency of the load driven by the motor 2, and a fundamental frequency that does not overlap with the predetermined frequency may be adopted as the predetermined format. In this case, even if the load significantly resonates, the fundamental frequency for application does not overlap with the predetermined frequency (resonant frequency), so the servo driver 4 can suitably extract and separate the detection signal.

[0041] Thirdly, as a predetermined format, the PWM frequency of the servo driver 4 is set to a high order frequency. As shown in FIG. 4, the amplitude of the driving current corresponding to the PWM frequency is generally larger than the amplitude of the driving current corresponding to the PWM frequency. Therefore, even if a frequency overlapping with the predetermined frequency is the fundamental frequency, as long as the detection signal is applied as a signal with a sufficiently large amplitude relative to the amplitude corresponding to the predetermined frequency, there will be no substantial problem in extracting the detection signal on the servo driver 4 side, and the detection signal can be suitably extracted. For example, even if the fundamental frequency of the applied detection signal overlaps with a high-order frequency f20 of the PWM frequency as shown in FIG. 4, if the amplitude of the applied signal is sufficiently large, In this case, the detection signal can be extracted by the servo driver 4 without any problem.

[0042] <Transmission Control> Here, the control relating to the transmission of the detection signal of the encoder 22 when driving the motor 2 having the above-mentioned transformer structure will be described with reference to Fig. 5. The transmission control shown in Fig. 5 is repeatedly executed by the detection unit 221 of the encoder 22. First, in S101, the speed of the motor 2 is detected. The speed of the motor 2 is calculated based on the position signal of the motor 2 detected by the detection unit 221. Next, in S102, the resonance of the load driven by the motor 2 is calculated. Data relating to the frequency is acquired. Specifically, before the motor 2 starts to be driven, data on the resonance frequency input by the user to the PLC 5 may be provided to the encoder 22 via the servo driver 4. Alternatively, if the detector 221 of the encoder 22 is configured to be able to detect the resonance of the load based on the detection signal, it is preferable to exclude the band of the resonance frequency related to that resonance when determining the fundamental frequency. Therefore, S1 In 02, when resonance can be detected, data on the resonance frequency can also be obtained.

[0043] Then, in S103, a fundamental frequency for applying a detection signal is determined based on the motor speed detected in S101 and the resonance frequency of the load acquired in S102. In determining the fundamental frequency, the fundamental frequency may be determined according to the first or second predetermined format described above.

[0044] 5 is constantly and repeatedly executed while the motor 2 is running, the fundamental frequency for applying the detection signal is adjusted in real time according to the speed and other factors of the motor 2. This allows for the detection signal to be suitably transmitted via the power line 11 and the winding portion 25.

[0045] (Second form) Next, a second embodiment of the arrangement of the transformer structure in the winding section 25 of the motor 2 will be described with reference to FIG. 6. The configuration of the winding section 25 of the motor body 21 is the same as that of the first embodiment, so a detailed description thereof will be omitted. In the second embodiment, each transformer structure is arranged in a manner similar to that of the winding section 25. 25. Specifically, in the second embodiment, for the transformer structures 53, 63, and 73 related to the first process, a primary coil 531 of the transformer structure 53 is connected between the U and V phases so as to be parallel to the U and V phase winding portions L5 and L6, a primary coil 631 of the transformer structure 63 is connected between the V and W phases so as to be parallel to the V and W phase winding portions L6 and L7, and a primary coil 731 of the transformer structure 73 is connected between the W and U phases so as to be parallel to the W and U phase winding portions L7 and L5. The secondary coils 532 of the transformer structure 53, the secondary coils 632 of the transformer structure 63, and the secondary coils 732 of the transformer structure 73 are connected to the encoder 22. For the transformer structure 80 related to the second process, a primary coil 801 of the transformer structure 80 is connected between the U and V phases, similar to the transformer structure 53, and a secondary coil 802 of the transformer structure 80 is connected to the supply unit 215.

[0046] In the second embodiment, the winding ratio of the transformer structure for each phase is basically the same, but may be different. In the embodiment shown in Fig. 6, a transformer structure for the first processing is disposed between all three phases in winding section 25, but it may be disposed between only two of the three phases. By disposing the transformer structure between at least two phases, redundancy in the transmission of the detection signal can be maintained.

[0047] By employing the winding section 25 and transformer structures 53, 63, 73, and 80 configured in this manner, it is possible to transmit the detection signal of the encoder 22 and supply power to the encoder 22 via the power line 11 and the winding section 25. With this configuration, no communication cable or power supply cable is required for the encoder 22, which greatly reduces the cabling work and reduces the cost.

[0048] (Third Form) Next, a third embodiment of the arrangement of the transformer structure in the winding section 25 of the motor 2 will be described with reference to FIG. 7. The configuration of the winding section 25 of the motor body 21 is the same as that of the first and second embodiments, and therefore a detailed description thereof will be omitted. The third embodiment is similar to the second embodiment in the arrangement for applying the detection signal of the encoder 22 between the phases of the winding section 25, but differs from the second embodiment in that the transformer structure described above is not used as the configuration for applying the detection signal of the encoder 22 for the first processing. Therefore, a detailed description of the third embodiment will focus on the differences from the second embodiment.

[0049] In the third embodiment, the configuration for applying the detection signal to the encoder 22 does not include the transformer structure described above, and the application configuration is configured to enable signal application between each phase of the winding 25 (between U and V, between V and W, and between W and U) via the insulating units 55, 65, and 75, respectively. The insulating units 55, 65, and 75 are electrical components that maintain insulation between the winding 25 and the encoder 22 so that the drive voltage of the winding 25 does not act on the encoder 22, and also enable application of the detection signal from the encoder 22. In the embodiment shown in FIG. 7, the application configuration for the first process is disposed between all three phases of the winding 25, but the application configuration for the first process may be disposed between only two of the three phases. By disposing the application configuration between at least two phases, redundancy in the transmission of the detection signal can be maintained.

[0050] By adopting the application configuration and transformer structure 80 using the winding section 25 and insulating sections 55, 65, and 75 configured in this manner, it is possible to transmit the detection signal of the encoder 22 and supply power to the encoder 22 via the power line 11 and the winding section 25. With this configuration, no communication cable or power supply cable is required for the encoder 22, which significantly reduces the cabling work and reduces the cost. Note that the technical idea shown in this third embodiment (a configuration for applying a detection signal for the first process without using a transformer structure) can be applied to other configurations disclosed in the present specification as long as no technical inconsistency occurs.

[0051] (Fourth Form) Next, a fourth embodiment of the arrangement of the transformer structure in the winding section 25 of the motor 2 will be described with reference to FIG. 8. The configuration of the winding section 25 of the motor body 21 is the same as that of the first embodiment, and therefore a detailed description thereof will be omitted. In the fourth embodiment, each transformer structure is arranged relative to the phases of the winding section 25. Specifically, in the fourth embodiment, for the transformer structures 53, 63, and 73 related to the first treatment, the primary coil 531 of the transformer structure 53 corresponding to the U phase is connected in parallel to the winding portions L5, L6, and L7 of the three phases, and the primary coil 631 of the transformer structure 63 corresponding to the V phase is connected in parallel, and the primary coil 731 of the transformer structure 73 corresponding to the W phase is connected in parallel. Specifically, line L50 including primary coil 531, line L60 including primary coil 631, and line L70 including primary coil 731 are Y-connected, and the other ends are connected to U-phase winding portion L5, V-phase winding portion L6, and W-phase winding portion L7, respectively. Secondary coil 532 of transformer structure 53, secondary coil 632 of V-phase transformer structure 63, and secondary coil 732 of W-phase transformer structure 73 are connected to encoder 22. Regarding transformer structure 80 related to the second processing, primary coil 801 of transformer structure 80 is connected in series to primary coil 531 of transformer structure 53, and secondary coil 802 of transformer structure 80 is connected to supply unit 215.

[0052] In the fourth embodiment, the winding ratio of the transformer structure for each phase is basically the same, but may be different. In the embodiment shown in Fig. 8, the transformer structure for the first processing is arranged to correspond to all three phases in the winding section 25, but it may be arranged to correspond to only two of the three phases. By arranging the transformer structure to correspond to at least two phases, redundancy in the transmission of the detection signal can be maintained.

[0053] By employing the winding section 25 and transformer structures 53, 63, 73, and 80 configured in this manner, it is possible to transmit the detection signal of the encoder 22 and supply power to the encoder 22 via the power line 11 and the winding section 25. With this configuration, no communication cable or power supply cable is required for the encoder 22, which greatly reduces the cabling work and reduces the cost.

[0054] (Fifth Form) Next, a fifth embodiment of the arrangement of the transformer structure in the winding section 25 of the motor 2 will be described with reference to FIG. 9. The configuration of the winding section 25 of the motor body 21 is the same as that of the first embodiment, and therefore a detailed description thereof will be omitted. In the fifth embodiment, the coil components 51, 61, and 71 of the winding portions L5, L6, and L7 of the respective phases are used as primary coils 531, 631, and 731 of the transformer structures 53, 63, and 73 related to the first process, corresponding to the respective phases. Specifically, in the U phase, the coil component 51 is used as the primary coil 531 to form the transformer structure 53; in the V phase, the coil component 61 is used as the primary coil 631 to form the transformer structure 63; and in the W phase, the coil component 71 is used as the primary coil 731 to form the transformer structure 73. Therefore, in the fifth embodiment, the secondary coils 532, 632, 732 of the transformer structures 53, 63, 73 of each phase are wound around the stator core together with the main coil of the winding portion, which is also the primary coil, to form the transformer structures 53, 63, 73 of each phase. The secondary coil 532 of the transformer structure 53, the secondary coil 632 of the V-phase transformer structure 63, and the secondary coil 732 of the W-phase transformer structure 73 are connected to the encoder 22. In addition, with respect to the transformer structure 80 related to the second processing, the primary coil 801 of the transformer structure 80 is connected in series to the primary coil 531 of the transformer structure 53, and the secondary coil 802 is connected to the supply unit 215.

[0055] In the fifth embodiment, the winding ratio of the transformer structure for each phase is basically the same, but may be different. In the embodiment shown in Fig. 9, a transformer structure for the first processing is disposed between all three phases in winding section 25, but it may be disposed between only two of the three phases. By disposing a transformer structure between at least two phases, redundancy in the transmission of the detection signal can be maintained.

[0056] By employing the winding section 25 and transformer structures 53, 63, 73, and 80 configured in this manner, it is possible to transmit the detection signal of the encoder 22 and supply power to the encoder 22 via the power line 11 and the winding section 25. With this configuration, no communication cable or power supply cable is required for the encoder 22, which greatly reduces the cabling work and reduces the cost.

[0057] (Variation) Transformer structures 53, 63, and 73 shown in Figure 9 and elsewhere are compound-winding transformer structures, but as a modification, single-winding transformer structures can also be employed. For example, when a single-winding transformer structure is employed in the configuration shown in Figure 9, the winding section 25 of motor 2 is used as a primary coil and a portion of winding section 25 is used as a secondary coil, thereby forming transformer structures 53, 63, and 73. In other words, the secondary coil portion of winding section 25 is shared between the primary side and the secondary side.

[0058] <Appendix 1> A motor (2) to which power is supplied from an external driver (4) via a power line (11), an input section (211) to which a driving current is input from the driver (4) via the power line (11); a winding section (25) having multiple phases and connected to the input section (211) inside the motor (2); a processing unit (214) that applies a detection signal from a detector (22) that detects movement of a drive shaft of the motor (2) to at least two of the multiple phases of the winding unit (25) or to at least two of the multiple phases in the winding unit (25) as a signal in a predetermined format so that the detection signal can be extracted on the driver (4) side; A motor comprising: <Appendix 2> the processing unit (214) applies the detection signal as a signal of the predetermined format to all of the multiple phases of the winding unit (25) or to all of the multiple phases in the winding unit (25); 10. The motor according to claim 1. <Appendix 3> a transformer structure (53, 63, 73) is provided, which includes a primary coil connected to each phase of the winding section (25) or between each phase in the winding section (25), and a secondary coil (532, 632, 732) corresponding to the primary coil (531, 631, 731); The processing unit (214) applies the detection signal to the secondary coil (532, 632, 732) corresponding to each phase or each interphase of the winding unit (25). 10. The motor according to claim 1 or 2. <Appendix 4> The processing unit (214) applies the detection signal to each phase of the winding unit (25) or between each phase via an insulating unit (55, 65, 75) for insulating the applied voltage of the winding unit (25). A motor according to appendix 1 or 2 <Appendix 5> the processing unit (214) is configured to apply the detection signal as a signal of the predetermined format having a fundamental frequency (f10) that does not overlap with a predetermined frequency associated with driving the motor (2) by the driver (4); The processing unit (214) varies the fundamental frequency in accordance with the variation of the predetermined frequency. 5. The motor according to any one of claims 1 to 4. <Appendix 6> The predetermined frequency is the PWM frequency (f0 ), and a higher frequency of the PWM frequency, 6. The motor according to claim 5. <Appendix 7> the predetermined frequency is a resonant frequency associated with a load driven by the motor; 6. The motor according to claim 5. <Appendix 8> The processing unit (214) converts the detection signal into a high-order PWM signal of the driver (4). The drive current is configured to be applied as a signal of the predetermined format having an amplitude greater than or equal to a predetermined time as compared with the amplitude of the drive current corresponding to the frequency. 5. The motor according to any one of claims 1 to 4. <Appendix 9> The processing unit (214) is further configured to extract a portion of the power generated by the drive current input to the winding unit (25) via the input unit (211) and supply the extracted power to the detector (22). 9. The motor according to any one of claims 1 to 8. [Explanation of symbols]

[0059] 2 motors 4 Servo drivers 22 Encoder 25 Winding section 53, 63, 73 Transformer structure 211 Connector (input part) 214 Processing section 215 Supply section

Claims

1. A motor that receives power from an external driver via a power line, an input unit to which a drive current is input from the driver via the power line; a winding section connected to the input section and having a plurality of phases within the motor; a processing unit that applies a detection signal from a detector that detects movement of the drive shaft of the motor to at least two of the multiple phases of the winding unit, or to at least two of the multiple phases in the winding unit, as a signal in a predetermined format so that the detection signal can be extracted on the driver side; A motor comprising:

2. the processing unit applies the detection signal as a signal of the predetermined format to all of the multiple phases of the winding unit or to all of the multiple phases in the winding unit; The motor according to claim 1 .

3. a transformer structure including a primary coil connected to each phase of the winding section or between each phase in the winding section, and a secondary coil corresponding to the primary coil; the processing unit applies the detection signal to the secondary coil corresponding to each phase or each inter-phase portion of the winding unit; The motor according to claim 1 or 2.

4. the processing unit applies the detection signal to each phase of the winding unit or between each phase of the winding unit via an insulating unit for insulating the applied voltage of the winding unit; The motor according to claim 1 or 2.

5. the processing unit is configured to apply the detection signal as a signal of the predetermined format having a fundamental frequency that does not overlap with a predetermined frequency associated with driving of the motor by the driver; the processing unit varies the fundamental frequency in response to a variation in the predetermined frequency; The motor according to claim 1 or 2.

6. The predetermined frequency is a PWM frequency of the driver corresponding to the rotation speed of the motor, and A higher order frequency of the PWM frequency, The motor according to claim 5.

7. the predetermined frequency is a resonant frequency associated with a load driven by the motor; The motor according to claim 5.

8. The processing unit converts the detection signal into a signal having a frequency corresponding to a higher order of the PWM frequency of the driver. The drive current is applied as a signal of the predetermined format having an amplitude greater than or equal to a predetermined time. The motor according to claim 1 or 2.

9. the processing unit is further configured to extract a portion of power due to the drive current input to the winding unit via the input unit, and supply the extracted power to the detector. The motor according to claim 1 or 2.

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