CN111684711B - Servo system, sensor hub, and diagnostic method for industrial device - Google Patents

Abstract

The purpose of the present invention is to provide a servo system that can accommodate a wide variety of sensors of different specifications. The sensor hub is connected to an encoder for detecting rotation of the motor, a sensor for detecting a state different from the rotation, and a servo amplifier for controlling driving of the motor, and the sensor hub is detachably connected to the encoder. The sensor hub performs signal processing on the encoder signal output from the encoder and the sensor signal output from the sensor, and transmits the signals to the servo amplifier.

Description

Diagnostic methods for servo systems, sensor hubs, and industrial devices

technical field

The present invention relates to a servo system, a sensor hub, and a diagnostic method for industrial equipment, and more particularly to a servo system with sensors that are effectively used in the control and maintenance of industrial equipment.

Background technique

In the field of FA (Factory Automation), various sensors detect the operation status of industrial equipment and the state of its surrounding environment, and it is required to construct an advanced communication system that effectively uses the detected signals to control equipment. As one of them, there is a servo system that performs drive control of industrial equipment. Generally, a servo system has a motor, a servo amplifier that drives the motor, and a controller that sends drive commands to the servo amplifier. An encoder that detects rotation information such as angle and angular velocity to control the rotation of the motor is installed near the rotation shaft of the motor. The servo amplifier controls the motor based on the drive command sent from the controller and the rotation information of the motor sent from the encoder.

In addition, in the servo system, a sensor that detects the state of the motor or its surroundings is used. By using the sensor, it can be effectively used for, for example, unsteady control of the drive sequence of the motor, improvement of control accuracy of the driven body of the motor, change of the control mode of the motor, and the like. In addition, by using a sensor to detect local abnormal noise, vibration, etc. of the motor or its surroundings, it can be effectively used for maintenance of industrial equipment. As described above, in order to effectively use the detection signal of the sensor for drive control and maintenance, a servo amplifier or a controller is required, or the controller needs to send it to a higher-level control device. On the other hand, in a servo system applied to an industrial device, the servo amplifier and the controller are often installed at a position away from the motor. In the above case, the signal line for transmitting the detection signal of the sensor installed on the motor or its surroundings to the servo amplifier and the controller becomes long, and the wiring work becomes cumbersome, and the detection signal may be lost. Transmission characteristics deteriorate.

To address the above problems, Patent Document 1 has an encoder that detects the motion of the motor and generates a feedback signal indicating the detected motion. The detection signal of the sensor for detection is received, and the feedback signal and detection signal are output to the control device, thereby shortening the length of the sensor cable and improving the cumbersome wiring work.

Patent Document 1: Japanese Patent Laid-Open No. 2015-95221

Contents of the invention

However, in the configuration in which the sensor cable is connected to the encoder, and the detection signal detected from the sensor and the feedback signal detected from the encoder are output to the control device, it is necessary to pre-install an input unit corresponding to the sensor specification. For the encoder, when a sensor of a specification that does not correspond to the input unit of the encoder is used, there is a problem that the encoder needs to be replaced each time.

The present invention was made in order to solve the above-mentioned problems, and an object of the present invention is to provide a servo system that can cope with various sensors having different specifications. In addition, the object is to provide a sensor hub to which sensors can be connected. In addition, the object is to provide a method for diagnosing an industrial device using a sensor hub.

The servo system according to the present invention has: a motor; an encoder that detects the rotation of the motor; a sensor hub that has a first connection part, a second connection part, and a third connection part, and the first connection part can It is detachably connected to the encoder, the second connection part is connected to a sensor for detecting a state different from the rotation, and the third connection part is connected to the sensor output from the encoder via the first connection part. A communication cable for transmitting an encoder signal and a sensor signal output from the sensor via the second connection unit, and the sensor hub includes a sensor determination unit that compares the sensor signal with the first sensor signal based on the voltage value of the sensor signal. 2. judging the connection status of the sensor connected to the connection part; The motor is driven and controlled.

The sensor hub according to the present invention has: a first connection part that is detachably connected to an encoder that detects the rotation of the motor; and a second connection part that connects a sensor that detects a state different from the rotation. ; and a third connection part, which is connected to a communication cable that connects the encoder signal output from the encoder through the first connection part and the sensor output from the sensor through the second connection part At least one of the signals is transmitted to a servo amplifier for driving and controlling the motor, and a connection state of the sensor connected to the second connection portion is determined based on a voltage value of the sensor signal.

A diagnostic method for an industrial device according to the present invention, the industrial device includes a servo system in which an encoder that detects the rotation of a motor and a servo amplifier that supplies current to the motor are connected via a device capable of A communication cable of a connector connected to the encoder is detachably connected, and the servo amplifier responds to the current supplied to the motor based on a detection signal of the encoder transmitted through the communication cable. The method for diagnosing an industrial device by performing adjustment and driving control is characterized by comprising the steps of connecting a sensor hub having first to third connection parts between the communication cable and the encoder, The encoder is connected to the first connection part, the sensor for detecting a state different from the rotation of the motor is connected to the second connection part, and the connector of the communication cable is connected to Connecting to the third connection part; sending the detection signal of the encoder from the encoder to the servo amplifier through the sensor hub and the communication cable; based on the The voltage value of the detection signal of the sensor determines the connection status of the sensor connected to the second connection part, and the sensor hub sends the determined connection status to the servo amplifier; via the sensor hub and the communication cable to transmit the detection signal of the sensor from the sensor to the servo amplifier; and based on the detection signal of the encoder and the detection signal of the sensor to the industrial The device is diagnosed.

The effect of the invention

According to the servo system of the present invention, the sensor hub is configured to be connected to the encoder, the sensor, and the servo amplifier respectively, and the sensor hub is detachably connected to the encoder, so that the sensor can be appropriately selected according to the specifications of the sensor to be connected. The hub can support various sensors. In addition, according to the sensor hub of the present invention, the encoder can be detachably connected in accordance with the specifications of the sensor, whereby signals output from the encoder and the sensor can be sent to the servo amplifier. Moreover, according to the diagnostic method of the industrial apparatus of this invention, a sensor can be added or replaced easily to a servo system by adding or replacing a sensor hub to a servo system.

Description of drawings

FIG. 1 is a schematic configuration diagram of a servo system according to Embodiment 1 of the present invention.

2 is a schematic configuration diagram of a sensor hub according to Embodiment 1 of the present invention.

3 is a schematic configuration diagram of a sensor hub according to Embodiment 1 of the present invention.

4 is a schematic diagram showing an example of the structure of a data frame generated by the sensor hub according to Embodiment 1 of the present invention.

5 is a flowchart showing the operation of the servo system according to Embodiment 1 of the present invention.

6 is a flowchart showing the operation of the servo system according to Embodiment 1 of the present invention.

7 is a schematic configuration diagram of a servo system according to Embodiment 2 of the present invention.

8 is a schematic configuration diagram of a sensor hub according to Embodiment 3 of the present invention.

9 is a schematic diagram showing an example of the structure of a data frame generated by the sensor hub according to Embodiment 3 of the present invention.

10 is a schematic configuration diagram of a servo system according to Embodiment 4 of the present invention.

11 is a flowchart showing a process of introducing a sensor hub into the servo system according to Embodiment 5 of the present invention.

Detailed ways

A servo system according to an embodiment of the present invention will be described based on the drawings. Next, a servo system including a rotary servo motor with one axis will be described as an example.

Implementation mode 1.

FIG. 1 is a schematic configuration diagram of a servo system according to Embodiment 1 of the present invention. As shown in FIG. 1 , the servo system 100 has: a motor 10; a controller 11 that generates a drive command for the motor 10; a servo amplifier 12 that controls the drive of the motor 10; an encoder 13 that detects the rotation of the motor 10 sensor 14, which detects other states that encoder 13 does not detect; and sensor hub 15, which receives the encoder signal S13 output from encoder 13 and the sensor signal S14 output from sensor 14, and sends to the servo amplifier 12. Here, the sensor 14 detects the state of the motor 10 or the surroundings of the motor 10 .

The motor 10 and the servo amplifier 12 are connected to each other via a power line cable C3 in order to supply current to the armature of the motor 10 . The servo amplifier 12 adjusts the supplied current based on the drive command from the controller 11 and the encoder signal S13 and the sensor signal S14 sent from the sensor hub 15 to control the drive of the motor 10 .

2 is a schematic configuration diagram of a sensor hub according to Embodiment 1 of the present invention. As shown in Figure 2, the sensor hub 15 has: a first connection part 15a (below, marked as an encoder connection part), which is connected to the encoder 13; a second connection part 15b (below, marked as a sensor connection part), which is connected to A sensor cable C4 connected at one end to the sensor 14 ; and a third connection portion 15 c (hereinafter referred to as an amplifier connection portion) connected to a communication cable C2 connected at one end to the servo amplifier 12 .

The encoder connection portion 15 a of the sensor hub 15 is, for example, a connector having a plurality of connection pins for connecting the encoder 13 . The encoder 13 has, for example, a connector 13 a formed with terminal holes corresponding to connection pins of the encoder connection portion 15 a of the sensor hub 15 . The connection pins of the encoder connection portion 15 a of the sensor hub 15 are fitted into the terminal holes of the connector 13 a of the encoder 13 , whereby the sensor hub 15 and the encoder 13 are detachably connected. Here, the encoder connection portion 15 a of the sensor hub 15 can also be a wiring board on which a conductive portion is printed, and can be connected by fitting with the connector 13 a of the encoder 13 . In addition, the encoder connection part 15a of the sensor hub 15 and the connector 13a of the encoder 13 can also be connected to each other via a cable.

The sensor connection part 15b of the sensor hub 15 is, for example, a connector having a plurality of connection pins for connecting three sensor cables C4. The shape of the sensor connection portion 15b and the number of connection pins are formed to correspond to the specifications of the connectors C4a, C4b, and C4c of the sensor cable C4. Here, the number of sensors 14 and sensor cables C4 can be appropriately changed. In addition, the connectors C4a, C4b, and C4c of the sensor cable C4 can also be integrated.

The amplifier connection portion 15 c of the sensor hub 15 is, for example, a connector having a terminal hole into which a connection pin of the connector C2 a of the communication cable C2 is fitted.

Here, the shape of the encoder connection portion 15a, the sensor connection portion 15b, and the amplifier connection portion 15c of the sensor hub 15, the number of connection pins, and the number of terminal holes are not limited to those shown in FIG. The servo system 100 can be appropriately changed according to the usage of the servo system 100 . In addition, the encoder connection part 15a, the sensor connection part 15b, and the amplifier connection part 15c can correspond to corresponding connectors, and can use a connection pin as a terminal hole and a terminal hole as a connection pin.

The sensor hub 15 receives the encoder signal S13 output from the encoder 13 via the encoder connection portion 15a and the sensor signal S14 output from the sensor 14 via the sensor connection portion 15b, and transmits the signal via the communication cable C2 connected to the amplifier connection portion 15c. sent to the servo amplifier 12.

In response to a command from the servo amplifier 12 , the sensor hub 15 determines the connection status of the sensor 14 connected to the sensor connection unit 15 b through the sensor determination unit 153 , and sends the determination result to the servo amplifier 12 . The connection status of the sensors 14 refers to, for example, the number of sensors 14 connected to the sensor connection portion 15b, the types of the sensors 14, the number of sensor signals S14, and the like. The connection status of the sensor 14 is determined by counting the number of sensor signals S14 detected within a predetermined period based on, for example, a change in the voltage value of the sensor signal S14.

The servo amplifier 12 receives the determination result and sets the communication standard between the sensor hub 15 and the servo amplifier 12 through the communication standard setting unit 122 . The sensor hub 15 converts the encoder signal S13 and the sensor signal S14 into serial signals through the signal processing unit 152 according to the set communication standard. The sensor hub 15 transmits the encoder signal S13 and the sensor signal S14 to the servo amplifier 12 through the communication cable C2 connected to the amplifier connection unit 15 c according to the communication standard set by the communication standard setting unit 122 .

As described above, the servo system 100 according to Embodiment 1 of the present invention has the sensor hub 15 having: the encoder connection part 15a detachably connected to the encoder 13; the sensor connection part 15b Connected to the sensor 14 via the sensor cable C4; and the amplifier connection part 15c, which is connected to the servo amplifier 12 via the communication cable C2, and the sensor hub 15 receives the encoder signal via the encoder connection part 15a and the sensor connection part 15b, respectively. S13 and sensor signal S14 are sent to the servo amplifier 12 via the amplifier connection part 15c and the communication cable C2.

With the above configuration, the sensor hub 15 can be appropriately selected according to the specifications of the sensor 14 to be connected, and the selected sensor hub 15 can be attached to the encoder 13 . Thereby, even when the sensor 14 with a different specification is newly installed, the encoder 13 does not need to be exchanged, so it can respond to various sensors 14 immediately.

Also, in the servo system 100 , the encoder 13 provided on the motor 10 and the sensor cable C4 connected to the sensor 14 provided on the motor 10 or its periphery are connected to the sensor hub 15 . With this structure, compared with the case where the sensor cable C4 is connected to the controller 11 or the servo amplifier 12 installed at a position away from the motor 10, the cumbersome work of wiring the sensor cable C4 can be improved, and the The transfer characteristic of the sensor signal S14 detected by the sensor 14 is improved.

In addition, in the servo system 100, the sensor hub 15 judges the connection state of the sensor 14 connected to the sensor connection part 15b, and based on the judgment result, the servo amplifier 12 sets the communication standard between the servo amplifier 12 and the sensor hub 15. Certainly. With this configuration, the servo system 100 can immediately read the sensor signal S14 through the servo amplifier 12 when the sensor hub 15 is replaced or the sensor hub 15 is added or changed.

The controller 11 generates drive commands such as the position and speed pattern of the motor 10 and sends them to the servo amplifier 12 . The controller 11 is a control device including a PLC (Programmable Logic Controller), a CPU (Central Processing Unit) for driving a motor, a DSP (Digital Signal Processor), a pulse generator, and the like.

The controller 11 and the servo amplifier 12 are connected via a network cable C1. As the network cable C1 , for example, a general-purpose communication cable such as a twisted-pair Ethernet (registered trademark) cable or an optical fiber cable can be used.

The servo amplifier 12 has: a transceiver unit 121 for transmitting and receiving signals with the sensor hub 15; a communication standard setting unit 122 for communicating with the servo amplifier 12 and the sensor hub 15 according to the connection status of the sensor 14 determined by the sensor hub 15; 15 to set the communication standard; and the parallel conversion unit 123, which converts the serial signal sent from the sensor hub 15 into a parallel signal.

The transceiver unit 121, the communication standard setting unit 122 and the parallel conversion unit 123 of the servo amplifier 12 are, for example, composed of an industrial microcomputer (CPU), ASIC (application specific integrated circuit), FPGA (field-programmable gate array), CPLD (Complex Programmable Logic Device) and other LSI (Large-Scale Integration) electronic circuits. In addition, data communication among the transmission and reception unit 121 , the communication standard setting unit 122 , and the parallel conversion unit 123 is performed by bus communication via a buffer and a memory (not shown) included in the servo amplifier 12 . Either one or both of the communication standard setting unit 122 and the parallel conversion unit 123 may be incorporated in an external device of the servo amplifier 12 .

The servo amplifier 12 and the sensor hub 15 are connected to each other via a communication cable C2 capable of bidirectional signal transmission and reception. The communication cable C2 has a connector C2a connected to the amplifier connection part 15c of the sensor hub 15, and supplies power from the servo amplifier 12 to the sensor hub 15, for example, at least one signal line of a digital signal or an analog signal line. The power cord for the voltage is included with the cable. The signal line and the power line may be connected by cables different from each other.

Serial communication is used for communication between the servo amplifier 12 and the sensor hub 15 . By applying serial communication, it is possible to reduce the number of signal lines of the communication cable C2. The communication method may be a half-duplex communication method or a full-duplex communication method, and a communication selection line for allowing the sensor hub 15 to identify the communication method may be included in the communication cable C2. In addition, in order to transmit signals of a temperature sensor, an acceleration sensor, etc. not shown built in the encoder 13, a communication line transmitted from the motor 10 to the controller 11 may be included in the communication cable C2.

The encoder 13 detects the rotation of the motor 10 and sends an encoder signal S13 indicating the detected rotation of the motor 10 to the sensor hub 15 . The encoder 13 has a transceiver unit 131 for transmitting an encoder signal S13 to the sensor hub 15 , and the transmitter and receiver unit 131 has a connector 13 a for connecting to the encoder connection unit 15 a of the sensor hub 15 . The rotation of the motor 10 detected by the encoder 13 is, for example, the angle, angular velocity, and angular acceleration of the rotating shaft. The encoder 13 is installed, for example, attached to the vicinity of the rotation shaft of the motor 10 .

The detection method of the encoder 13 is an absolute value method, an incremental method, or the like. The encoder 13 may have a detector such as a temperature sensor inside to output the state of the detection circuit of the encoder 13 and an alarm at the time of signal detection. In addition, the encoder 13 may include an acceleration sensor inside, for example, in order to detect wear and deterioration of a bearing mechanism included in the motor 10 and a driving reaction force when the motor rotates. When the encoder 13 also detects other states different from the rotation of the motor 10, the detection result (detection results of a temperature sensor, an acceleration sensor, etc. provided in the encoder 13) is sent together with the rotation information of the motor 10 to Sensor hub 15.

The encoder signal S13 is an electrical signal transmitted from the transceiver unit 131 of the encoder 13 to the sensor hub 15, for example, the rotation information of the motor 10 detected by the encoder 13, the temperature sensor included in the detection circuit of the encoder 13, etc. The detected internal information of the encoder 13 and the alarm information of the encoder 13.

The sensor 14 detects the state of a detection target different from the rotation of the motor 10 which is a detection target of the encoder 13 , and transmits a sensor signal S14 indicating the detected state to the sensor hub 15 . The sensor 14 detects, for example, the temperature, vibration, sound, etc. of the motor 10 or the periphery of the motor 10 as a state of a detection target different from the rotation of the motor 10 . The periphery of the motor 10 refers to, for example, a driven body of the motor 10 , a stand for fixing the motor 10 , and an object on which the driven body acts. The object on which the driven body acts refers to, for example, a component grasped by a robot driven by the motor 10 , a workpiece processed by a processing machine driven by the motor 10 , and the like. The sensor 14 is, for example, an acceleration sensor or a camera. In addition, position sensors, speed sensors, pressure sensors, microphones, gyro sensors, flow sensors, temperature sensors, illuminance sensors, magnetic sensors, infrared sensors, and the like can also be used.

The sensor 14 is provided in at least any one of the motor 10 , the encoder 13 , the driven body of the motor 10 , the stand that fixes the motor 10 , or the object to which the driven body acts. In addition, it is also possible to install them around them using jigs and brackets. In addition, the sensor 14 may detect an absolute state of the object to be measured, or may detect a relative state.

The sensor signal S14 is an electrical signal transmitted from the sensor 14 to the sensor hub 15 via the sensor cable C4. Here, the sensor signal S14 transceived between the sensor 14 and the sensor hub 15 may be compressed or modulated. The sensor signal S14 transmitted and received between the sensor 14 and the sensor hub 15 is, for example, a signal including an analog signal or a digital signal transmitted by a single-ended method or a differential method, and a ground signal indicating a reference of the signal.

The sensor 14 and the sensor hub 15 are connected to each other via a sensor cable C4. The sensor cable C4 is at least one communication cable that transmits the sensor signal S14 output from the sensor 14 to the sensor hub 15 . When the sensor 14 outputs a digital signal, the sensor hub 15 and the sensor 14 may be connected by parallel communication or by serial communication. By applying serial communication, it is possible to reduce the number of signal lines.

The communication between the sensor 14 and the sensor hub 15 can adopt, for example, RS (TIA/EIA) 232/422/485, USB (Universal Serial Bus), I2C (Inter Integrated Circuit), SPI (Serial Peripheral Interface), I2S (Inter IC Sound ), 1-Wire, Ethernet (registered trademark)/IP, 10BaseT and other serial communication standards. The transmission mode of serial communication can be synchronous or asynchronous.

The sensor cable C4 may include not only a signal line for transmitting the sensor signal S14 output from the sensor 14 to the sensor hub 15 but also a power line for supplying electric power from the sensor hub 15 to the sensor 14 . When the sensor cable C4 has a plurality of signal lines and power lines, they can be bundled and covered with vinyl, shielded wires, etc., and a part or the whole can be integrated as a composite communication cable. When a microphone and a camera are used as the sensor 14, the audio signal of the microphone and the video signal of the camera can be transmitted via a HDMI (High-Definition Multimedia Interface) (registered trademark) cable by a transmission method such as TMDS (Transition Minimized Differential Signaling). sent simultaneously.

In addition, when using a sensor 14 capable of wirelessly transmitting the sensor signal S14, a wireless base station such as WSN (Wireless Sensor Networks) may be installed in the sensor hub 15 to receive the sensor signal S14 and transmit it via the communication cable C2. to the transceiver unit 121 of the servo amplifier 12 . As a result, compared with the case where the base station is installed in the controller 11 or the servo amplifier 12, the wireless traveling distance can be shortened, and the delay and reliability of communication can be improved.

3 is a schematic configuration diagram showing a sensor hub according to Embodiment 1 of the present invention. The sensor hub 15 has: a transceiver unit 151, which transmits and receives signals to the encoder 13, the sensor 14, and the servo amplifier 12; a signal processing unit 152, which processes the signals transmitted and received; Make a judgment.

The signal processing unit 152 has an AD conversion unit 152a that converts an analog signal into a digital signal, and a serial conversion unit 152b that converts a parallel signal into a serial signal. The serial conversion unit 152 b converts the sensor signal S14 into a serial signal based on the data frame structure of the serial communication set by the communication standard setting unit 122 of the servo amplifier 12 . The sensor hub 15 transmits the encoder signal S13 and the sensor signal S14 to the servo amplifier 12 through serial communication of two different systems, for example.

Here, the serial conversion unit 152b may combine the encoder signal S13 and the sensor signal S14 into one serial signal, and transmit it to the servo amplifier 12 through one system of serial communication. In addition, when a plurality of sensors 14 are connected, the serial conversion unit 152b can combine the plurality of sensor signals S14 into one serial signal, and transmit it to the servo amplifier 12 through serial communication of one system. The number of signal lines between the servo amplifier 12 and the sensor hub 15 can be reduced by using one system of serial communication.

In addition, the serial conversion unit 152b may lengthen the interval of the sensor signal S14 to convert it into a signal having a period different from the sampling period of the sensor signal S14, or may delete redundant data in order to suppress the data capacity. In addition, the sensor hub 15 may superimpose alarm information such as a communication alarm signal and an electric power alarm signal generated when a communication error or an electric power error is detected on the serial signal, or may display diagnostic information such as the ambient temperature and operating time of the sensor hub 15 Add to serial signal.

The sensor judging unit 153 judges the number of sensors 14, the type of sensors 14, the number of sensor signals S14, etc. as the connection status of the sensors 14 based on the voltage value of the sensor signal S14, for example, and outputs the judgment result to the transmission and reception of the sensor hub 15. Section 151.

The signal processing unit 152 of the sensor hub 15 is realized by an electronic circuit including an analog circuit, a packaged IC (Integrated Circuit), an industrial microcomputer (CPU), an ASIC, an FPGA, or an LSI such as a CPLD. The signal processing unit 152 may include a filter processing unit and a buffer processing unit (not shown) in order to remove noise and improve communication accuracy. In addition, the signal processing unit 152 may include a multiplexer and a switching IC when there are many kinds and numbers of analog sensor signals S14 to be AD-converted.

4( a ) and ( b ) are diagrams showing an example of a structure of a data frame of serial communication generated by the serial conversion unit of the sensor hub according to Embodiment 1 of the present invention. Figure 4(a), (b) are data frames of encoder signal S13 and sensor signal S14 respectively. As shown in FIGS. 4( a ) and ( b ), the encoder signal S13 and the sensor signal S14 are transmitted by, for example, serial communication of two different systems.

A data frame of serial communication is composed of, for example, a header, a data field, and a trailer. The header is an area for transmitting communication standards such as alarm information and bit rate related to the operating state of the encoder 13 or the sensor 14 . The tail is an area where an error detection code is transmitted, and the servo amplifier 12 detects errors such as transmission path noise accompanying data transfer based on the tail. As an error detection method, a parity check, a checksum, a cyclic redundancy check, or the like can be applied.

The data field is an area where the framed encoder signal S13 or sensor signal S14 is transmitted, and the signal is composed of a start bit, data bit, parity bit, stop bit, and the like. As shown in Figure 4 (b), in the case of the sensor 14 such as an acceleration sensor and a pressure sensor, the data fields are three acceleration sensor signals S141a, S141b, S141c in the X axis, Y axis, and Z axis directions output by the acceleration sensor Composite with the pressure sensor signal S142 output by the pressure sensor.

Next, the operation of the servo system 100 when setting the communication standard between the servo amplifier 12 and the sensor hub 15 will be described. 5 is a flowchart showing the operation of the servo system according to Embodiment 1 of the present invention. In the following, it is assumed that the sensor signal S14 from the sensor 14 is output to the sensor hub 15 in an analog format.

The servo amplifier 12 transmits a discrimination request signal S03 requesting discrimination of the sensor 14 to the sensor hub 15 ( ST101 ). The sensor hub 15 receives the sensor signal S14 from the sensor 14 (ST102). The sensor hub 15 converts the received analog sensor signal S14 into a digital signal by the AD converter 152a for a predetermined period of time (ST103). The period during which AD conversion is performed is set to, for example, the shortest update period of the serial communication that can be performed by the servo amplifier 12 or the sensor hub 15 .

The sensor hub 15 converts the sensor signal S14 into a serial signal by the serial conversion unit 152b (ST104). The sensor hub 15 discriminates the number of sensor signals S14 through the sensor discriminating unit 153 based on the change in the voltage value of the sensor signal S14 ( ST105 ). For example, when the voltage of the sensor signal S14 is higher or lower than the threshold value for a certain period, it is deemed that the sensor signal S14 is received, and the number of the sensor signal S14 is determined.

The sensor hub 15 sends the number of sensor signals S14 discriminated by the sensor discriminating unit 153 to the servo amplifier 12 as the sensor discriminating signal S16 ( ST106 ).

The communication standard setting unit 122 of the servo amplifier 12 sets the communication standard between the servo amplifier 12 and the sensor hub 15 based on the sensor discrimination signal S16 ( ST107 ). The communication standard setting unit 122 sets the data frame of the serial communication between the servo amplifier 12 and the sensor hub 15 . The number of data frames and sensor signals S14 set by the communication standard setting unit 122, the type of sensor signals S14, the data size of sensor signals S14, the transmission order of sensor signals S14, and the communication method between sensors 14 and sensor hub 15 Decide accordingly.

The servo system 100 can set the communication standard between the sensor hub 15 and the servo amplifier 12 according to the sensor 14 connected to the sensor hub 15 by executing ST101 to ST107 . Accordingly, it is possible to optimize the update cycle, communication speed, and communication data volume of serial communication according to the sensors 14 connected to the sensor connection portion 15 b of the sensor hub 15 .

A part of ST101 to ST107 may be omitted, or the order of a part may be reversed. For example, the parallel system sensor signal S14 converted into a digital signal by the AD conversion unit 152a may be sent to the sensor determination unit 153 without passing through the serial conversion unit 152b. In addition, the number of sensor signals S14 discriminated by the sensor discriminating unit 153 and the communication specification between the servo amplifier 12 and the sensor hub 15 may be stored in a recording circuit (not shown) included in the sensor hub 15 . By calling the stored content when the servo system 100 is running, the operations of steps ST101 to ST107 can be omitted.

Next, the operation of transmitting the signals detected by the encoder 13 and the sensor 14 to the servo amplifier 12 via the sensor hub 15 according to the communication standard set in ST101 to ST107 will be described based on FIG. 6 . 6 is a flowchart showing the operation of the servo system according to Embodiment 1 of the present invention. Next, the encoder signal S13 detected by the encoder 13 is converted into a serial signal inside the encoder 13 , and serial communication is established between the encoder 13 and the sensor hub 15 .

The servo amplifier 12 transmits to the sensor hub 15 a first communication request signal S01 requesting a response under the communication standard set in ST101 to ST107 (ST201). The first communication request signal S01 designates a communication standard such as a bit rate, a communication frequency band, and an update cycle between the servo amplifier 12 and the sensor hub 15, and requests a response from the encoder signal S13 or the sensor signal S14.

Based on the first communication request signal S01 , the sensor hub 15 generates a second communication request signal S02 requesting a response from the encoder 13 according to the set communication standard, and sends it to the encoder 13 ( ST202 ). The second communication request signal S02 designates a communication standard between the encoder 13 and the sensor hub 15 such as a bit rate, a communication frequency band, and an update cycle, and requests the encoder 13 to respond to the encoder signal S13 . The encoder 13 transmits the encoder signal S13 to the sensor hub 15 according to the communication standard specified by the second communication request signal S02 (ST203).

The sensor hub 15 receives the sensor signal S14 from the sensor 14, and converts it into a digital signal by the AD converter 152a (ST204). The serial conversion unit 152b performs serial conversion on the sensor signal S14 according to the communication standard specified by the first communication request signal S01. The serial conversion unit 152b combines, for example, the plurality of sensor signals S14 into a serial number in response to the combination request signal S04 requesting combination of the plurality of sensor signals S14 generated by the transceiver unit 151 of the sensor hub 15 based on the first communication request signal S01. The line signal is output as the sensor composite signal S15 (ST205).

The sensor hub 15 transmits the encoder signal S13 and the sensor composite signal S15 to the servo amplifier 12 through serial communication of two different systems, for example ( ST206 ).

The servo amplifier 12 separates the combined sensor signal S15 into parallel signals by the parallel conversion unit 123 to obtain the encoder signal S13 and the sensor signal S14 ( ST207 ). At this time, by including the sensor discrimination signal S16 in the sensor composite signal S15 , it is possible to separate the sensor composite signal S15 by the parallel conversion unit 123 of the servo amplifier 12 .

The servo system 100 executes ST201 to ST207, whereby the encoder signal S13 and the sensor signal S14 can be obtained based on the communication standard set by the communication standard setting unit 122 of the servo amplifier 12 .

A part of ST201 to ST207 may be omitted or the order of a part may be reversed. The communication method of the serial signal is not limited to the synchronous method. The communication mode of the serial signal can be any mode of half-duplex and full-duplex. In addition, various request signals may include a clock signal for synchronous communication. In addition, the second communication request signal S02 is a signal whose need and content are changed depending on the motor 10 and the encoder 13 , and the second communication request signal S02 may not be used depending on the types of the motor 10 and the encoder 13 .

As described above, servo system 100 according to Embodiment 1 of the present invention includes sensor hub 15 detachably connected to encoder 13 , and sends encoder signal S13 and sensor signal S14 to servo amplifier 12 via sensor hub 15 . With this configuration, the sensor hub 15 can be appropriately selected according to the specifications of the sensor 14 and connected to the encoder 13 . Accordingly, the driving of the motor 10 can be controlled using information from various sensors 14 .

In addition, the servo system 100 discriminates the connection state of the sensor 14 through the sensor discriminating unit 153 of the sensor hub 15, and based on the discriminating result, the communication standard setting unit 122 of the servo amplifier 12 controls the communication between the servo amplifier 12 and the sensor hub 15. Specifications are set. With this configuration, the servo system 100 can immediately read the sensor signal S14 through the servo amplifier 12 when the sensor hub 15 is replaced, or when the sensor hub 15 is added or the sensor 14 is changed. In addition, the servo system 100 can optimize the update cycle, communication speed, and communication data volume of the serial communication between the sensor hub 15 and the servo amplifier 12 .

In addition, the encoder connection portion 15a of the sensor hub 15 preferably has the same shape as the connector C2a included in the communication cable C2, and is configured with the same pin allocation. In addition, it is preferable that the amplifier connection portion 15c of the sensor hub 15 has the same shape as the connector 13a of the encoder 13, and is configured with the same pin allocation.

By configuring as described above, the sensor hub 15 is used during start-up and maintenance of the servo system 100 , and the sensor hub 15 used during operation can be removed to connect the connector C2a of the communication cable C2 to the encoder 13 .

In addition, in the servo system 100 , it is preferable to supply electric power from the servo amplifier 12 to the sensor hub 15 , the encoder 13 , and the sensor 14 . The electric power supplied from the servo amplifier 12 is sent to the sensor hub 15 as a power signal via the power line of the communication cable C2 , and supplied to the circuit board of the encoder 13 and the sensor 14 (not shown) via the sensor hub 15 .

By configuring as described above, the sensor hub 15 can receive power from the servo amplifier 12, and the sensor hub 15 can be easily replaced.

Here, the power signal includes, for example, a positive or negative electric line and a ground line. The power transmitted by the power signal may be a DC signal or an AC signal. In addition, the sensor hub 15 may include a step-up or step-down circuit in order to increase the types of power lines supplied to the sensors 14 . Thereby, the number of sensors 14 connected to the sensor hub 15 can be increased. In addition, a battery may be mounted on the sensor hub 15 so as not to be affected by voltage fluctuations of the servo amplifier 12 and the device power supply. When the supply power of the servo amplifier 12 is insufficient or the supply voltage fluctuates greatly, power may be supplied to any one or more of the sensor hub 15 , encoder 13 , and sensor 14 from outside the sensor hub 15 .

In addition, the sensor hub 15 is preferably configured such that the specification of the sensor 14 corresponding to one sensor hub 15 can be limited, and the sensor hub 15 is appropriately replaced according to the specification of the sensor 14 . Accordingly, compared with a case where one sensor hub 15 supports various sensors 14 , it is possible to keep the board size and setting data of the sensor hub 15 small without redundant hardware and software.

In addition, in FIG. 1 , the example in which the sensor hub 15 is mounted sideways on the motor 10 from the vertical direction is shown, but the sensor hub 15 only needs to be arranged in a place where it is easy to secure a space around the encoder 13, EMC (Electromagnetic Compatibility) A good venue will do. In addition, the sensor hub 15 may be divided into two or more circuit boards and structures. For example, the encoder connection unit 15a and the signal processing unit 152 may be connected via a cable.

Implementation mode 2.

A servo system 100 according to Embodiment 2 for carrying out the present invention will be described based on FIG. 7 . Here, descriptions overlapping with those of the servo system 100 according to Embodiment 1 are appropriately simplified or omitted. In FIG. 7 , the same reference numerals as in Embodiment 1 denote the same or corresponding parts. The servo system 100 according to the present embodiment has a sensor hub 15 to which a sensor 14b that outputs a serial format digital signal can be connected in addition to the sensor 14 that outputs an analog signal.

7 is a schematic configuration diagram of a servo system according to Embodiment 2 of the present invention. The sensor hub 15 has an encoder connection part 15 a, a sensor connection part 15 b, and an amplifier connection part 15 c, and the encoder connection part 15 a is detachably connected to the encoder 13 . In addition, the sensor connection part 15b of the sensor hub 15 is connected to the three sensors 14 outputting an analog signal and the sensor 14b outputting a serial digital signal via a sensor cable C4, for example. The number of sensors 14, 14b and sensor cables C4 is not limited thereto, and can be changed appropriately.

The sensor 14b is, for example, a microphone, and sends a monophonic sound signal to the sensor hub 15 in serial form as a sensor signal S14b. The sensor 14b communicates with the sensor hub 15 through, for example, I2S. At this time, the sensor cable C4 includes transmission lines for SCLK (Serial Clock) signals, WDCLK (Word Clock) signals, and SD (Serial Data) signals.

The signal processing part 152 of the sensor hub 15 has the serial interface (serial I/F) 152c which converts the SD signal transmitted from the sensor 14b by I2S format into a voltage value. The sensor signal S14b converted into a voltage value through the serial interface 152c is output to the sensor judging part 153, and the number of the sensors 14, 14b, the type of the sensor 14, 14b, and the sensor signal S14, S14b are determined as the connection status of the sensors 14, 14b. quantity etc.

When setting the communication standard between the sensor 14b and the sensor hub 15, the servo amplifier 12 sequentially sends the third communication request signal S05 of various serial communication methods corresponding to the sensor hub 15 to the sensor 14b via the sensor hub 15. .

The third communication request signal S05 specifies communication specifications such as a bit rate, a communication frequency band, and an update cycle between the sensor 14b corresponding to the sensor hub 15 and the sensor hub 15, and requests a response of the sensor signal S14b. For example, when it is confirmed whether the sensor 14b can respond by the I2S method, the servo amplifier 12 sends the WDCLK signal and the SCLK signal to check whether the response specified by the communication standard of the I2S method can be obtained at a predetermined timing. Thereby, communication specifications between the sensor hub 15 and the sensor 14b can be set.

The form of communication between the sensor hub 15 and the sensor 14b can be, for example, RS (TIA/EIA) 232/422/485, USB (Universal Serial Bus), I2C (Inter Integrated Circuit), SPI (Serial Peripheral Interface) other than I2S. ), 1-Wire, Ethernet/IP (registered trademark), 10BaseT and other serial communication standards, the transmission mode of serial communication can be synchronous or asynchronous. The serial interface 152c can be realized by a URAT (Universal Asynchronous Receiver/Transmitter) of an industrial microcomputer or a transceiver IC.

The communication standard setting unit 122 of the servo amplifier 12 sets the communication standard between the sensor hub 15 and the servo amplifier 12 according to the connection status of the sensors 14 and 14 b discriminated by the sensor judging unit 153 of the sensor hub 15 . The sensor hub 15 transmits the encoder signal S13 transmitted through the encoder connection part 15a and the sensor signals S14 and S14b transmitted through the sensor connection part 15b through the communication connection with the amplifier connection part 15c according to the set communication standard. The signal is sent to the servo amplifier 12 through the cable C2.

As described above, according to the second embodiment of the present invention, the servo system 100 includes the sensor hub 15 having the encoder connection part 15a detachably connected to the encoder 13, and the sensor connection part 15b. , which can be connected to the sensor 14b output in a serial form; and the amplifier connection part 15c, which connects the communication cable C2 that transmits the encoder signal S13 and the sensor signal S14, S14b to the servo amplifier 12, and passes the sensor 14 according to the specification By appropriately selecting the sensor hub 15 and attaching it to the encoder 13 , it is possible to cope with various sensors 14 .

In addition, even when the sensor 14b and the sensor hub 15 are transmitting and receiving by serial communication, the connection status of the sensors 14 and 14b can be discriminated by the sensor discriminating unit 153, and the servo amplifier 12 and the The communication specifications of the serial communication between the sensor hubs 15 are set, and the update cycle, communication speed, and communication data volume of the serial communication can be optimized.

In addition, the specification of the serial communication method between the sensor 14b and the sensor hub 15 may be limited. Thereby, the number of serial communication ports provided in the sensor connection part 15b can be reduced, and the sensor hub 15 can be made compact and low-cost.

Implementation mode 3.

A servo system 100 according to Embodiment 3 for carrying out the present invention will be described based on FIGS. 8 and 9 . Here, descriptions overlapping with those of the servo system 100 according to Embodiment 1 are appropriately simplified or omitted. In FIGS. 8 and 9 , the same reference numerals as in Embodiment 1 denote the same or corresponding parts. The servo system 100 according to the present embodiment is configured so that the encoder signal S13 and the sensor signal S14 are communicated in a serial form of two different systems in the servo system 100 according to the first embodiment. The signal S13 and the sensor signal S14 are combined and communicated in a serial format of one system.

8 is a schematic configuration diagram of a sensor hub according to Embodiment 3 of the present invention. As shown in FIG. 8 , the sensor hub 15 has: an encoder connection part 15a, which is detachably connected to the encoder 13; a sensor connection part 15b, which is connected to a sensor cable C4 whose one end is connected to the sensor 14; and an amplifier connection part. 15c, one end of which is connected to the communication cable C2 of the servo amplifier 12.

The signal processing unit 152 of the sensor hub 15 receives the encoder signal S13 on the basis of the sensor signal S14. The transceiver unit 151 of the sensor hub 15 generates a composite request signal S04 requesting to composite the encoder signal S13 and the sensor signal S14 according to the data frame structure of the serial signal specified by the first communication request signal S01 . The serial conversion unit 152b composites the encoder signal S13 and the sensor signal S14 into a serial signal in response to the composite request signal S04, and outputs it as a composite signal S17. The sensor hub 15 transmits the composite signal S17 to the servo amplifier 12 through serial communication of one system.

As an example, a case where the encoder signal S13 of 2 bytes is combined with the sensor signal S14 of 5 bytes in total and transmitted from the sensor hub 15 to the servo amplifier 12 will be described. Here, the sensor 14 is an acceleration sensor, a pressure sensor, and a microphone.

The sensor signals S14 are 1 byte digital data, ie acceleration sensor signals S141a, S141b, S141c, pressure sensor signals S142, and microphone signals S143 in the X-axis, Y-axis, and Z-axis directions. Here, the data size of the encoder signal S13 and the sensor signals S141a, S141b, S141c, S142, and S143, the number of sensors 14, and the data frame structure of the serial communication can be appropriately changed.

If the communication standard setting section 122 of the servo amplifier 12 recognizes that the number of sensor signals S14 received by the signal processing section 152 is five based on the sensor discrimination signal S16, it sends the first communication request signal S01 to the serial conversion section 152b. send. The first communication request signal S01 includes information on a data frame structure for simultaneously transmitting a 2-byte encoder signal S13 and a total of 5-byte sensor signals S14 through serial communication of one system.

The data capacity of the serial communication that can be transmitted with one update is 5 bytes, while the total data capacity of the encoder signal S13 and the sensor signals S141a, S141b, S141c, S142, and S143 is 7 bytes.

In the case as described above, the data transmitted for each update cycle is divided, the interval is lengthened, compression, etc. are performed. For example, the serial conversion unit 152b of the sensor hub 15 converts the data for each update cycle of the serial communication between the servo amplifier 12 and the sensor hub 15 to either one or both of the encoder signal S13 and the sensor signal S14. Segmented signal processing.

FIG. 9 is an example of the structure of a data frame of serial communication generated by the serial conversion unit. As shown in FIG. 9 , the communication standard setting section 122 of the servo amplifier 12 transmits to the serial conversion section 152 b of the sensor hub 15 an instruction to generate an encoder signal S13 necessary for the rotation control of the motor 10 every transmission , The data frame of each sensor signal S141a-c, S142, S143 is sent every 2 update cycles. According to this instruction, the serial conversion unit 152b generates a data frame as shown in FIG. 9 , adds the data frame to the data field of serial communication, and transmits it.

Here, an example is shown in which the sensor hub 15 divides the data for each update period, but signal processing for increasing the interval of data may be performed for either one or both of the encoder signal S13 and the sensor signal S14. In addition, the sensor hub 15 may perform signal processing for compressing data on either one or both of the encoder signal S13 and the sensor signal S14.

In addition, the data S200 missing when the data interval is increased or compressed may be superimposed as additional information. In FIG. 9 , in the even-numbered update cycle, data is added S200 to the communication capacity of one data frame (1 byte).

In addition, in order to reduce the amount of data transmitted by the sensor hub 15 , the feature quantity of the encoder signal S13 or the sensor signal S14 may be extracted and transmitted to the servo amplifier 12 . For example, the sensor hub 15 may perform signal processing for converting data in the time domain to data in the frequency domain for either one or both of the encoder signal S13 and the sensor signal S14 .

As described above, according to the servo system 100 according to Embodiment 3 of the present invention, by making the sensor hub 15 detachable from the encoder 13, the sensor hub 15 can be appropriately selected according to the specifications of the sensor 14 and can be connected with the sensor hub 15. The encoder 13 is connected, and it can correspond to various sensors 14 . In addition, in the servo system 100, the sensor hub 15 generates a composite signal S17 that combines the encoder signal S13 and the sensor signal S14, and can transmit it to the servo amplifier 12 through serial communication of one system, so that the signal line of the communication cable C2 can be connected. Wiring saving.

In addition, the sensor hub 15 performs signal processing such as dividing data, lengthening the data interval, and compressing the encoder signal S13 and the sensor signal S14 for each update cycle, so that even in the case where the encoder signal S13 and the sensor signal S14 can be transmitted with one update, Even when the data capacity of the serial communication is large, the encoder signal S13 and the sensor signal S14 can be transmitted.

Implementation mode 4.

A servo system 100 according to Embodiment 4 for carrying out the present invention will be described based on FIG. 10 . Here, descriptions overlapping with those of the servo system 100 according to Embodiment 1 are appropriately simplified or omitted. In FIG. 10 , the same reference numerals as in Embodiment 1 denote the same or corresponding parts. The servo system 100 according to the present embodiment has a higher-level processing device 101 that specifies the driving timing of the servo system 100 based on the execution plan of the entire industrial device including the servo system 100 .

The upper-level processing device 101 is, for example, a control device of an industrial device for the purpose of centralized management of the entire system including a cloud, an edge computer, an IPC (Industrial Personal Computer), and an MES (Manufacturing Execution System).

The upper-level processing device 101 is connected to the controller 11 through a network cable C0 capable of bidirectional signal transmission and reception. The servo system 100 has a higher-level processing device 101 , and the controller 11 can control the rotation of the motor 10 based on the execution plan of the entire industrial device by specifying the driving timing of the motor 10 .

In addition, by analyzing the sensor signal S14 from the sensor 14, the upper-level processing device 101 can diagnose the deterioration over time of the industrial device, etc. Preventive maintenance, planned maintenance.

For example, in an existing servo system 100 that operates by directly connecting the encoder 13 and the servo amplifier 12 with a predetermined communication cable, the existing communication cable C2 shown in FIG. 10 is used. The communication cable connects the sensor hub 15 between the existing communication cable and the encoder 13, enabling the upper-level processing device 101 to diagnose the industrial device based on the sensor signal S14 from the sensor 14 connected to the sensor hub 15. .

The servo system 100 can also be configured such that, when the sensor hub 15 has already been connected and the new sensor 14 cannot be connected or identified through the existing sensor hub 15, the existing sensor hub 15 can be replaced with one that can be connected or identified. The new sensor hub 15 for this sensor 14 is identified. If the diagnosis is temporary, the replaced sensor hub 15 may be restored to the original sensor hub 15 after the diagnosis, or the replaced sensor hub 15 may continue to be used for driving control of the motor 10 . The sensor hub 15 for diagnosis may transmit the encoder signal S13 from the encoder 13 to the host processing device 101 for diagnosis, or may not use the encoder signal S13 for the diagnosis.

In addition, the encoder connection portion 15 a may not be provided in the sensor hub 15 , and the diagnosis may be performed in a state where the encoder 13 is not connected to the sensor hub 15 . When the replaced sensor hub 15 is also used for drive control of the motor 10 , the sensor hub 15 is provided with a function of transmitting the encoder signal S13 from the encoder 13 to the servo amplifier 12 .

Implementation mode 5.

Next, an example of implementation of a method for diagnosing an industrial device by connecting the sensor hub 15 to the servo system 100 will be described. 11 is a flowchart showing a process of introducing a sensor hub into the servo system according to Embodiment 5 of the present invention. Next, a case where the sensor hub 15 is added to the existing servo system 100 to which the servo amplifier 12 and the encoder 13 are connected will be described.

The user of the servo system 100 turns off the power of the servo amplifier 12 to install the sensor hub 15, and removes the connector C2a of the communication cable C2 from the connector 13a of the encoder 13 (ST301).

The user of the servo system 100 connects the sensor hub 15 to the servo amplifier 12, the encoder 13, and the sensor 14, respectively (ST302). The user of the servo system 100 connects the connector C2 a of the communication cable C2 to the amplifier connection part 15 c of the sensor hub 15 , thereby connecting the servo amplifier 12 and the sensor hub 15 . In addition, the user of the servo system 100 attaches the sensor hub 15 to the encoder 13 by connecting the encoder connection portion 15 a to the connector 13 a of the encoder 13 . The user of the servo system 100 connects the sensor 14 and the sensor hub 15 by connecting the connector C4a of the sensor cable C4 to the sensor connection part 15b. Here, the order of the installation jobs can be reversed.

The user of the servo system 100 confirms that there is no wiring error between the servo amplifier 12, the encoder 13, the sensor 14, and the sensor hub 15 by visual inspection, a tester, or the like (ST303).

The user of the servo system 100 turns on the power of the servo amplifier 12, and supplies electric power from the servo amplifier 12 to the sensor hub 15, the encoder 13, and the sensor 14 (ST304). The user of the servo system 100 confirms that the power supply to the sensor hub 15, the encoder 13, and the sensor 14 is normal by visual inspection, a tester, or the like (ST305).

In order to easily confirm that the power is normally supplied, the sensor hub 15 can monitor the fluctuation of the power supply voltage through an arithmetic circuit such as an industrial microcomputer, and the sensor hub 15 or the lamp of the servo amplifier 12 can be turned on or blinked or beeped. Notify electricity alarm. When the sensor hub 15 outputs an electric power alarm, an external power supply can be used for the sensor 14 or the sensor hub 15 added to the servo system 100 .

In addition, when the power supply from the servo amplifier 12 to the sensor hub 15 or the sensor 14 cannot be normally performed, it is possible to replace the sensor 14 or the sensor hub 15 with a specification with a different operating voltage and current capacity so that the power supply can be performed. supply. Return to the case of replacing the sensor 14 or the sensor hub 15 (ST302).

When the power supply to the sensor hub 15 is normal, the sensor judging section 153 of the sensor hub 15 judges the connection state of the sensor 14 connected to the sensor connecting section 15b, and the servo amplifier 12 performs a communication between the servo amplifier 12 and the sensor hub 15. Set the communication standard of the device (ST306). The sensor hub 15 transmits the encoder signal S13 and the sensor signal S14 to the servo amplifier 12 and the host processing device 101 according to the set communication standard (ST307). The detailed operations of ( ST306 ) and ( ST307 ) are the same as ( ST101 ) to ( ST107 ) and ( ST201 ) to ( ST207 ) of Embodiment 1, and thus are omitted.

By executing ST301 to ST307, the encoder signal S13 and the sensor signal S14 are sent to the servo amplifier 12 and the host processing device 101, and diagnosis for performing drive control and preventive maintenance of industrial devices including the servo system 100 can be performed. The diagnostic method of an industrial device using the sensor hub 15 according to Embodiment 5 of the present invention can use the existing motor 10, communication cable C2, and encoder 13 by adding or replacing the sensor hub 15, so that the sensor can be 14 are easily added to the servo system 100.

( ST301 ) to ( ST307 ) may be partially omitted, or the order of some parts may be reversed and implemented. In addition, although the method of adding the sensor hub 15 to the existing servo system 100 was shown in this form, when installing the servo system 100 newly, you may integrate the sensor hub 15 into the servo system 100.

In addition, in Embodiments 1 to 5, a one-axis rotary motor was described as an example of the motor 10, but it is not limited to the rotary motor, and the movable member may be moved in the translation direction with respect to the fixed member. driven linear motor.

In addition, in the present invention, a plurality of constituent elements disclosed in Embodiments 1 to 4 can be appropriately combined without departing from the gist thereof.

Explanation of labels

100 servo system, 10 motor, 11 controller, 12 servo amplifier, 13 encoder, 14 sensor, 15 sensor hub, 15a encoder connection part, 15b sensor connection part, 15c amplifier connection part, 151 transceiver part, 152 signal processing part , 153 sensor discrimination section.

Claims (11)

1. A servo system, comprising:

a motor;

an encoder that detects rotation of the motor;

A sensor hub including a 1 st connection unit, a 2 nd connection unit, and a 3 rd connection unit, the 1 st connection unit being detachably connected to the encoder, the 2 nd connection unit being connected to a sensor that detects a state different from the rotation, the 3 rd connection unit being connected to a communication cable that transmits an encoder signal output from the encoder via the 1 st connection unit and a sensor signal output from the sensor via the 2 nd connection unit, the sensor hub including a sensor determination unit that determines a connection state of the sensor connected to the 2 nd connection unit based on a voltage value of the sensor signal; and

a servo amplifier for performing drive control of the motor based on the encoder signal, the sensor signal, and a drive command transmitted from a controller transmitted via the communication cable,

the connection status of the sensors includes the number of the sensors, the category of the sensors, or the number of the sensor signals.

2. A servo system as recited in claim 1, wherein,

the sensor hub transmits the connection status determined by the sensor determination unit to the servo amplifier via the communication cable.

3. A servo system as claimed in claim 1 or 2, characterized in that,

the communication cable has a connector connected to the 3 rd connection of the sensor hub,

the encoder has a connector detachably connected to the 1 st connection portion of the sensor hub,

the connector of the communication cable is connectable with the connector of the encoder.

4. A servo system as claimed in claim 1 or 2, characterized in that,

the sensor hub has a signal processing unit that converts at least one of the encoder signal and the sensor signal into a serial signal.

5. A servo system as claimed in claim 1 or 2, characterized in that,

the servo amplifier includes a communication specification setting unit that sets a communication specification between the servo amplifier and the sensor hub based on the connection status of the sensor connected to the 2 nd connection unit of the sensor hub.

6. A sensor hub, comprising:

a 1 st connection unit detachably connected to an encoder for detecting rotation of the motor;

A 2 nd connection unit for connecting a sensor for detecting a state different from the rotation; and

a 3 rd connection unit connected to a communication cable for transmitting at least any one of the encoder signal outputted from the encoder via the 1 st connection unit and the sensor signal outputted from the sensor via the 2 nd connection unit to a servo amplifier for controlling driving of the motor,

determining a connection condition of the sensor connected to the 2 nd connection portion based on a voltage value of the sensor signal,

the connection status of the sensors includes the number of the sensors, the category of the sensors, or the number of the sensor signals.

7. The sensor hub of claim 6, wherein the sensor hub is configured to,

the connection status of the sensor is sent to the servo amplifier via the communication cable.

8. The sensor hub of claim 6 or 7, wherein,

comprises a signal processing unit for converting the encoder signal and the sensor signal into serial signals,

and transmitting the sensor signal to the servo amplifier according to the set communication standard according to the connection status of the sensor connected to the 2 nd connection part.

9. A diagnostic method for an industrial device comprising a servo system in which an encoder for detecting rotation of a motor and a servo amplifier for supplying current to the motor are detachably connected via a communication cable having a connector connectable to the encoder, the servo amplifier adjusting the current supplied to the motor based on a detection signal of the encoder transmitted via the communication cable to perform drive control,

the diagnostic method of the industrial device is characterized by comprising the following steps:

a sensor hub having 1 st to 3 rd connection portions between the communication cable and the encoder, the sensor hub connecting the encoder to the 1 st connection portion, connecting a sensor detecting a state different from the rotation of the motor to the 2 nd connection portion, and connecting the connector of the communication cable to the 3 rd connection portion;

transmitting the detection signal of the encoder from the encoder to the servo amplifier via the sensor hub and the communication cable;

Determining a connection condition of the sensor connected to the 2 nd connection unit based on a voltage value of a detection signal of the sensor, the sensor hub transmitting the determined connection condition to the servo amplifier;

transmitting a detection signal of the sensor from the sensor to the servo amplifier via the sensor hub and the communication cable; and

diagnosing the industrial device based on the detection signal of the encoder and the detection signal of the sensor,

the connection status of the sensors includes the number of the sensors, the category of the sensors, or the number of the sensor signals.

10. The method for diagnosing an industrial apparatus according to claim 9, wherein,

and transmitting the determined connection information to the servo amplifier via the cable.

11. A diagnostic method for an industrial device according to claim 9 or 10, wherein,

the method includes the step of converting the detection signal of the encoder and the detection signal of the sensor into serial signals and transmitting the serial signals to the servo amplifier via the sensor hub and the communication cable.