Drive unit

Abstract

To provide a technique capable of omitting external wiring connected to an input terminal that may be unused in a driving device for driving a load device such as an electric motor.SOLUTION: An inverter device 1 is provided with: input terminals EN1 and EN2 to which a signal line from an emergency stop switch ES can be connected; an input circuit 240 that is connected to the input terminals EN1 and EN2 and that receives signal inputted via the input terminals EN1 and EN2; and a selector switch 250 for switching a first state in which the input circuit 240 is unable to receive signal inputted via the input terminals EN1 and EN2 or the inverter device 1 is unable to use signal received in the input circuit 240, and a second state in which the input circuit 240 is able to receive signal inputted via the input terminals EN1 and EN2 or the inverter device 1 is able to use signal received in the input circuit 240.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a drive device. [Background technology]

[0002] For example, a drive device is known that drives a load device such as an electric motor while utilizing an external input signal (see Patent Document 1).

[0003] Patent Document 1 discloses a servo driver that activates a safety function (safe torque off function) of a motor to be driven, using an input signal that corresponds to the operating state of an emergency stop switch. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Publication No. 2018-136712 Summary of the Invention [Problem to be solved by the invention]

[0005] However, there may be cases where the target input signal is not used, for example, when a certain function such as the above-mentioned safety function is disabled, etc. In this case, the input terminal of the device corresponding to the target input signal is not connected to the signal line for transmitting the target input signal, and is in an unused state.

[0006] However, when an input terminal is unused, it may be necessary to maintain (fix) the potential of the input circuit that receives the target input signal in a state where the target input signal is not input. For this reason, for example, when the drive device is shipped, a method is adopted in which a power supply or the like is short-circuited with the unused input terminal using external wiring such as a short-circuit bar or jumper wire, and the potential of the unused input terminal is fixed. This may result in problems such as increased costs due to the man-hours required for wiring the external wiring and malfunction of the drive device due to mistakes in the wiring work.

[0007] In view of the above problems, an object of the present invention is to provide a technology that makes it possible to omit external wiring connected to an input terminal that is assumed to be unused in a drive device that drives a load device such as an electric motor. [Means for solving the problem]

[0008] In order to achieve the above object, in one embodiment of the present disclosure, an input terminal to which a predetermined signal line can be connected; an input circuit connected to the input terminal and configured to receive a signal input through the input terminal; a switching unit that switches between a first state in which the drive device cannot use a signal received by the input circuit and a second state in which the drive device can use a signal received by the input circuit; a signal utilization unit that utilizes a signal input through the input terminal; Equipped with 、 The switching unit switches between the first state in which the output line of the input circuit and the input line of the signal utilization unit are disconnected and the second state in which the output line of the input circuit and the input line of the signal utilization unit are connected. R, A drive arrangement is provided. In another embodiment of the present disclosure, an input terminal to which a predetermined signal line can be connected; an input circuit connected to the input terminal and configured to receive a signal input through the input terminal; a switching unit that switches between a first state in which the drive device cannot use the signal received by the input circuit and a second state in which the drive device can use the signal received by the input circuit, the switching unit switches between the first state in which the potential of the input circuit is maintained within the predetermined range and the second state in which the potential of the input circuit can be changed in accordance with the signal input from the input terminal, by switching an open / closed state of a connection line connecting a predetermined portion of the input circuit and a constant potential unit in which a potential is maintained within a predetermined range; the input circuit has a photocoupler including a photodiode connected to the input terminal by a signal line, and a phototransistor connected to an output terminal by a signal line; The predetermined portion is a signal line connecting the phototransistor and the output terminal. A drive arrangement is provided. Effect of the Invention

[0010] According to the above-described embodiment, in a drive device that drives a load device such as an electric motor, it is possible to omit external wiring that is connected to an input terminal that is assumed to be unused. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram illustrating an example of a configuration of an inverter device. [Diagram 2] FIG. 1 is a diagram illustrating an example of a configuration of an inverter device. [Diagram 3] FIG. 1 is a diagram showing a configuration of an inverter device according to a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment will be described with reference to the drawings.

[0013] [Inverter device configuration] First, the configuration of an inverter device 1 according to this embodiment will be described with reference to Figs.

[0014] Fig. 1 and Fig. 2 are diagrams showing an example of the configuration of the inverter device 1 according to this embodiment. Specifically, Fig. 1 is a diagram showing the state of the inverter device 1 in an operation mode in which a safety function related to the electric motor M operates, and Fig. 2 is a diagram showing the state of the inverter device 1 in a non-operation mode in which the safety function related to the electric motor M does not operate.

[0015] The inverter device 1 (an example of a drive device) generates AC power having a predetermined voltage and a predetermined frequency based on power input via at least one of an AC input unit ACIN and a DC input unit DCIN, and drives a load device.

[0016] For example, as shown in Fig. 1 and Fig. 2, the inverter device 1 rectifies AC power of a commercial power source CPS input through an AC input unit ACIN, converts it into DC power, and converts the DC power into a predetermined AC power to drive an electric motor M (an example of a load device). For example, the inverter device 1 may convert DC power input from a DC common bus or the like through a DC input unit DCIN into a predetermined AC power to drive the electric motor M. For example, the inverter device 1 may convert both the DC power input through the DC input unit DCIN and the DC power converted from the AC power input through the AC input unit ACIN into a predetermined AC power to drive the electric motor M. For example, the inverter device 1 may drive a load device other than the electric motor M based on the power input through at least one of the AC input unit ACIN and the DC input unit DCIN.

[0017] 1 and 2, the inverter device 1 includes a main circuit section 100 and a control circuit section 200. Various components of the inverter device 1, including the components of the main circuit section 100 and the control circuit section 200 of the inverter device 1, are housed inside a housing 1H or attached to the surface of the housing 1H in a manner that they are exposed to the outside of the housing 1H.

[0018] The main circuit section 100 includes an AC input section ACIN, a rectifier circuit 110, a smoothing circuit 120, an inverter circuit 130, an AC output section ACOUT, a charging circuit 140, and a DC input section DCIN.

[0019] The AC input unit ACIN is used to input three-phase AC power of R, S, and T phases from the outside. In this example, the AC input unit ACIN can receive three-phase AC power of R, S, and T phases through three power lines extending from a commercial power source CPS. The AC input unit ACIN includes an AC input terminal R, an AC input terminal S, and an AC input terminal T connected to the R, S, and T phase power lines, respectively.

[0020] The rectifier circuit 110 is configured to be capable of rectifying three-phase AC power of R phase, S phase, and T phase input from the AC input unit ACIN and outputting DC power. The rectifier circuit 110 has positive and negative output terminals connected to one end of a positive line PL and a negative line NL, respectively, and can output DC power to the smoothing circuit 120 through the positive line PL and the negative line NL. The rectifier circuit 110 is, for example, a bridge-type full-wave rectifier circuit including six diodes and having three sets of two-diode series connections constituting upper and lower arms connected in parallel.

[0021] The smoothing circuit 120 suppresses and smoothes pulsations in the DC power output from the rectifier circuit 110, the DC power input via the DC input unit DCIN, and the DC power regenerated from the inverter circuit .

[0022] The smoothing circuit 120 includes a smoothing capacitor 122 and a reactor 124 .

[0023] The smoothing capacitor 122 is provided in parallel with the rectifier circuit 110 and the inverter circuit 130 in a path connecting the positive line PL and the negative line NL.

[0024] The smoothing capacitor 122 smoothes the DC power output from the rectifier circuit 110, the DC power input from the DC input unit DCIN, and the DC power output (regenerated) from the inverter circuit 130 while repeatedly charging and discharging as appropriate.

[0025] There may be one smoothing capacitor 122. Alternatively, a plurality of smoothing capacitors 122 may be disposed, and the plurality of smoothing capacitors 122 may be connected in parallel or in series between the positive line PL and the negative line NL. Alternatively, the plurality of smoothing capacitors 122 may be configured in such a way that a series connection of two or more smoothing capacitors 122 is connected in parallel between the positive line PL and the negative line NL.

[0026] The reactor 124 is provided in the positive line PL between the rectifier circuit 110 and the smoothing capacitor 122 (specifically, a branch point from the path in which the smoothing capacitor is arranged). For example, as shown in Fig. 1 and Fig. 2, the reactor 124 may be arranged to connect between reactor connection terminals LT1, LT2 drawn to the outside from both ends of the positive line PL separated between the rectifier circuit 110 and the smoothing capacitor 122. Also, for example, the reactor 124 may be built inside the housing 1H of the inverter device 1.

[0027] The reactor 124 generates a voltage to appropriately prevent changes in current, while smoothing the DC power output from the rectifier circuit 110, the DC power input from the DC input unit DCIN, and the DC power output (regenerated) from the inverter circuit 130.

[0028] Incidentally, the reactor 124 may be omitted. In this case, a short-circuiting conductor is connected between the reactor connection terminals LT1 and LT2 in FIG.

[0029] The inverter circuit 130 has positive and negative input terminals connected to the other terminals of the positive line PL and the negative line NL. The inverter circuit 130 converts the DC power supplied from the smoothing circuit 120 through the positive line PL and the negative line NL into three-phase AC power of U-phase, V-phase, and W-phase having a predetermined frequency and a predetermined voltage by switching operations of semiconductor switching elements, and outputs the three-phase AC power to the electric motor M. The semiconductor switching elements may be, for example, insulated gate bipolar transistors (IGBTs) or metal-oxide-semiconductor field-effect transistors (MOSFETs) made of silicon (Si). The semiconductor switching elements may also be, for example, semiconductor elements using wide band gap semiconductors such as silicon carbide (SiC) and gallium nitride (GaN).

[0030] The inverter circuit 130 includes, for example, six semiconductor switching elements, and is configured to include a bridge circuit in which three sets of series-connected bodies (switch legs) of two semiconductor switching elements constituting upper and lower arms are connected in parallel between a positive line PL and a negative line NL. The inverter circuit 130 may output three-phase AC power through a U-phase wire, a V-phase wire, and a W-phase wire drawn from the connection points of the three sets of upper and lower arms. A free wheel diode may be connected in parallel to each of the six semiconductor switching elements.

[0031] The AC output unit ACOUT is connected to the electric motor M through three power lines of U-phase, V-phase, and W-phase. The AC output unit ACOUT includes an AC output terminal U, an AC output terminal V, and an AC output terminal W connected to the U-phase, V-phase, and W-phase power lines, respectively.

[0032] The charging circuit 140 is provided in a portion of the positive line PL between the rectifier circuit 110 and the smoothing capacitor 122. For example, as shown in Fig. 1 and Fig. 2, the charging circuit 140 may be provided in a portion of the positive line PL between the rectifier circuit 110 and the reactor 124. Furthermore, for example, the charging circuit 140 may be provided in a portion of the positive line PL between the reactor 124 and the smoothing capacitor 122. The charging circuit 140 includes a switch 142 and a charging resistor 144.

[0033] The switch 142 is provided in a portion of the positive line PL between the rectifier circuit 110 and the smoothing circuit 120 (reactor 124). The switch 142 is configured to be able to open and close the positive line PL. The switch 142 is, for example, a switching element such as a thyristor, a triac, or a relay.

[0034] The charging resistor 144 is connected in parallel with the switch 142 .

[0035] The charging circuit 140 functions so that a current flowing through the positive line PL toward the smoothing circuit 120 passes through the switch 142 when the switch 142 is turned on, and passes through the charging resistor 144 when the switch 142 is turned off. As a result, when the inverter device 1 is started up, the switch 142 is turned off so that a current flows through the charging resistor 144, and it is possible to prevent a relatively large inrush current when charging the smoothing capacitor 122. Then, when the smoothing capacitor 122 is charged to a certain extent and the voltage between the positive line PL and the negative line NL becomes relatively high, the inverter device 1 turns on the switch 142, and a current can flow to the positive line PL through the switch 142 having a relatively low electric resistance. Specifically, when a voltage detection circuit (not shown) that detects the voltage between the positive line PL and the negative line NL detects a voltage equal to or higher than a predetermined value, it is determined that the inrush current has been suppressed, and the switch 142 is changed from an off state to an on state.

[0036] The DC input unit DCIN is used to input DC power from an external source. The DC input unit DCIN includes a positive DC terminal P and a negative DC terminal N.

[0037] The positive DC terminal P is drawn from the positive line PL. For example, as shown in Fig. 1 and Fig. 2, the positive DC terminal P may be drawn from a portion of the positive line PL between the charging circuit 140 and the inverter circuit 130, specifically, between the reactor 124 and the inverter circuit 130. Also, for example, as described above, when the positional relationship between the reactor 124 and the charging circuit 140 in the positive line PL is reversed from that in Fig. 1 and Fig. 2, the positive DC terminal P may be drawn from a portion of the positive line PL between the reactor 124 and the charging circuit 140.

[0038] The negative DC terminal N is drawn from an arbitrary position of the negative line NL. For example, as shown in Fig. 1, the negative DC terminal N is connected to a portion of the negative line NL between the smoothing circuit 120 (smoothing capacitor 122) and the inverter circuit 130 inside the housing 1H.

[0039] The direct current input unit DCIN may be omitted.

[0040] The control circuit section 200 performs control related to the inverter device 1.

[0041] The functions of the control circuit section 200 may be realized by any hardware or any combination of hardware and software, etc. For example, the control circuit section 200 is configured by a computer or the like including a CPU (Central Processing Unit), a memory device such as a RAM (Random Access Memory), a non-volatile auxiliary storage device such as a ROM (Read Only Memory), and an interface device for input / output with the outside.

[0042] The control circuit section 200 includes a drive circuit 210, a control section 220, a cutoff circuit 230, a power supply terminal PLC, input terminals EN1 and EN2, a common terminal CM, an input circuit 240, and a changeover switch 250.

[0043] Under the control of the control unit 220, the drive circuit 210 outputs a drive signal for driving the semiconductor switching element to turn on and off to the inverter circuit 130 (the gate of the semiconductor switching element).

[0044] The control unit 220 generates a drive signal such as a PWM (Pulse Width Modulation) signal for realizing a predetermined operating state of the electric motor M, and outputs the drive signal to the inverter circuit 130 (semiconductor switching element) through the drive circuit 210. This enables the control unit 220 to operate the inverter circuit 130 and control the drive of the electric motor M.

[0045] The interruption circuit 230 (an example of a signal utilization unit) is provided on a path (signal line) between the control unit 220 and the drive circuit 210. The interruption circuit 230 interrupts the signal path between the control unit 220 and the drive circuit 210 in response to a predetermined digital signal (hereinafter, "safety signal") input from input terminals EN1 and EN2 and received by the input circuit 240. Specifically, when a safety signal is input from at least one of input circuits 241 and 242 described below, the interruption circuit 230 interrupts the signal path between the control unit 220 and the drive circuit 210. As a result, the interruption circuit 230 interrupts the transmission of the drive signal from the control unit 220 to the drive circuit 210, and as a result, the power supply from the main circuit unit 100 to the load device (electric motor M) can be interrupted. Therefore, the control circuit unit 200 can realize safe torque off (STO) as a safety function that interrupts the power supply to the load device using the interruption circuit 230 based on a safety signal input from the outside.

[0046] The power supply terminal PLC is configured to be able to output the power of the internal power supply IPS to the outside. The power supply terminal PLC is provided on the surface of the housing 1H, and is connected to the positive terminal of the internal power supply IPS inside the housing 1H via a diode for preventing backflow.

[0047] The input terminals EN1 and EN2 are configured to be connectable to a signal line that transmits a digital signal (safety signal) for activating a safety function.

[0048] For example, as shown in Fig. 1, in the operation mode of the safety function, the input terminals EN1 and EN2 are connected to the emergency stop switch ES. Also, as shown in Fig. 2, in the inoperation mode of the safety function, the input terminals EN1 and EN2 are not connected to signal lines and are in an unused state.

[0049] The emergency stop switch ES is actuated in response to an operation by a user, such as a worker in a factory where equipment electrically driven by the electric motor M is installed, and can manually output a safety signal.

[0050] The emergency stop switch ES has two normally closed switches connected in parallel built in. One end of each of the two switches is connected to the input terminals EN1 and EN2 by signal lines, and the other end of each is connected to the power supply terminal PLC by signal lines.

[0051] When the emergency stop switch ES is not operated, the two switches are closed. Therefore, the input terminals EN1 and EN2 Power terminal PLC A signal line shorts the circuit between the emergency stop switch ES and the input terminals EN1 and EN2 outside the housing 1H. Therefore, when the emergency stop switch ES is not operated, a digital signal in a high (HIGH) state with a relatively high potential (hereinafter, referred to as an "H signal") is constantly input to the input terminals EN1 and EN2.

[0052] On the other hand, when the emergency stop switch ES is operated, the two switches transition from the closed state to the open state. Power terminal PLC When the emergency stop switch ES is operated, a digital signal having a relatively low potential (hereinafter, referred to as an "L signal") that corresponds to a safety signal is input to the input terminals EN1 and EN2.

[0053] The common terminal CM is a terminal of a reference potential common to the input terminals EN1 and EN2. The common terminal CM may be grounded inside the housing 1H. Also, the common terminal CM may be grounded, for example, through a signal line connected to the outside.

[0054] The input circuit 240 receives a safety signal input from the input terminals EN1 and EN2, and outputs the safety signal to the interrupter circuit 230.

[0055] The input circuit 240 includes input circuits 241 and 242.

[0056] The input circuit 241 is provided between the input terminal EN1 and the interrupter circuit 230, and is configured to be able to receive a safety signal input from the input terminal EN1 and output it to the interrupter circuit 230.

[0057] The input circuit 241 includes a photocoupler 241A and an input resistor 241B.

[0058] The photocoupler 241A includes a photodiode 241A1 and a phototransistor 241A2.

[0059] The photodiode 241A1 has an anode connected to the input terminal EN1 via an input resistor 241B by a signal line, and a cathode connected to the common terminal CM by a signal line.

[0060] The phototransistor 241A2 has a collector connected to the constant voltage power supply CVS by a signal line, and an emitter grounded via an output resistor and connected to the cutoff circuit 230 by a signal line. The constant voltage power supply CVS (an example of a constant potential unit) is a power supply circuit having an output voltage of, for example, 5V (volts).

[0061] The input circuit 242 is provided between the input terminal EN2 and the interrupter circuit 230, and is configured to be able to receive a safety signal input from the input terminal EN2 and output it to the interrupter circuit 230.

[0062] The input circuit 242 includes a photocoupler 242A and an input resistor 242B.

[0063] The photocoupler 242A includes a photodiode 242A1 and a phototransistor 242A2.

[0064] The photodiode 242A1 has an anode connected to the input terminal EN2 via an input resistor 242B by a signal line, and a cathode connected to the common terminal CM by a signal line.

[0065] The collector of the phototransistor 242A2 is connected to the constant voltage power supply CVS by a signal line, and the emitter is grounded via an output resistor and is also connected to the cutoff circuit 230 by a signal line.

[0066] The changeover switch 250 (an example of a changeover unit) switches the open / close state of a path between the constant voltage power supply CVS and the signal lines on the output sides of the input circuits 241 and 242, i.e., the signal lines connected to the emitters of the phototransistors 241A2 and 242A2. The changeover switch 250 mechanically switches the open / close state by, for example, a user's operation. The changeover switch 250 is provided, for example, in a place (for example, on the board of the control circuit unit 200) that is easily visible to the user when the openable / closable cover of the housing 1H is open, and may be a slide switch that the user can slide between two positions.

[0067] The changeover switch 250 includes changeover switches 251 and 252 .

[0068] The changeover switch 251 switches between an open and closed state of a path between the constant voltage power supply CVS and a signal line on the output side of the input circuit 241. When the changeover switch 251 is turned on and in a closed state, the path between the constant voltage power supply CVS and the signal line on the output side of the input circuit 241 becomes conductive, and the signal line on the output side of the input circuit 241 is maintained (fixed) at a relatively high potential, that is, a potential equivalent to an H signal.

[0069] The changeover switch 252 switches between an open and closed state of a path between the constant voltage power supply CVS and the signal line on the output side of the input circuit 242. When the changeover switch 252 is turned on and enters a closed state, the path between the constant voltage power supply CVS and the signal line on the output side of the input circuit 242 enters a conductive state, and the signal line on the output side of the input circuit 242 is maintained (fixed) at a potential corresponding to an H signal.

[0070] The changeover switches 251 and 252 are configured so that, for example, the user can individually turn them on and off. Alternatively, the changeover switches 251 and 252 may be configured so that, for example, the user can collectively turn them on and off.

[0071] As shown in FIGS. 1 and 2, the changeover switches 251 and 252 are turned OFF in a safety function operation mode, and turned ON in a safety function non-operation mode.

[0072] [Specific operation of the input circuit] Next, the specific operation of the input circuit 240 will be described with continued reference to FIG. 1 and FIG.

[0073] <Safety function operation mode> As shown in FIG. 1, in the safety function operation mode, as described above, the emergency stop switch ES is connected to the input terminals EN1 and EN2 via a signal line, and the change-over switches 251 and 252 are set to the OFF state.

[0074] When the emergency stop switch ES is not operated, as described above, an H signal is input to the input terminals EN1 and EN2. Therefore, a current flows from the input terminals EN1 and EN2 to the common terminal CM in the photodiodes 241A1 and 242A1 of the photocouplers 241A and 242A, and the phototransistors 241A2 and 242A2 are brought into a conductive state (ON state). Therefore, a conductive state is established between the constant voltage power supply CVS and the cutoff circuit 230, and an H signal is input to the cutoff circuit 230.

[0075] In this case, the interruption circuit 230 maintains the signal path between the control unit 220 and the drive circuit 210 in a connected state, and the control unit 220 can output a drive signal to the inverter circuit 130 through the drive circuit 210.

[0076] On the other hand, when the emergency stop switch ES is operated, as described above, an L signal is input as a safety signal to the input terminals EN1 and EN2. Therefore, no current flows through the photodiodes 241A1 and 242A1 of the photocouplers 241A and 242A, and the phototransistors 241A2 and 242A2 are brought into a non-conductive state (OFF state). Therefore, a non-conductive state is established between the constant voltage power supply CVS and the cutoff circuit 230, and an L signal is input as a safety signal to the cutoff circuit 230.

[0077] In this case, the interruption circuit 230 interrupts the signal path between the control unit 220 and the drive circuit 210. This allows the inverter device 1 to maintain a state in which it is not possible to output a drive signal from the control unit 220 to the drive circuit 210.

[0078] Furthermore, as described above, when a safety signal (L signal) is input from at least one of the input circuits 241, 242, the interruption circuit 230 can interrupt the signal path between the control unit 220 and the drive circuit 210. Therefore, for example, even if one of the normally-closed switches built into the emergency stop switch ES fails and is unable to output a safety signal, the interruption circuit 230 can interrupt the signal path between the control unit 220 and the drive circuit 210 in response to the safety signal from the other switch. Similarly, even if one of the input circuits 241, 242 fails and is unable to transmit a safety signal to the interruption circuit 230, the interruption circuit 230 can interrupt the signal path between the control unit 220 and the drive circuit 210 in response to the safety signal transmitted by the other switch.

[0079] Thus, in the safety function operation mode, the input circuit 240 transmits the safety signal input from the input terminals EN1, EN2 to the cutoff circuit 230, and the cutoff circuit 230 cuts off the signal path between the control unit 220 and the drive circuit 210 in response to the input of the safety signal. This allows the inverter device 1 to realize a safety function (STO) that stops the power supply to the electric motor M in response to the input of the safety signal by operating the emergency stop switch ES.

[0080] <Safety function inactive mode> As shown in FIG. 2, in the inoperative mode of the safety function, as described above, the input terminals EN1 and EN2 are unused, and the change-over switches 251 and 252 are in the ON state.

[0081] When the changeover switches 251 and 252 are turned on, as described above, the signal lines on the output side of the input circuits 241 and 242 are brought into a conductive state with the constant voltage power supply CVS and are maintained (fixed) at a relatively high potential, so that the state in which the H signal is input from the input circuits 241 and 242 to the cutoff circuit 230 is maintained.

[0082] In this case, the interruption circuit 230 maintains the signal path between the control unit 220 and the drive circuit 210 in a connected state, and the control unit 220 can output a drive signal to the inverter circuit 130 through the drive circuit 210.

[0083] In this way, by switching the changeover switches 251, 252 to the ON state, the signals input from the input circuits 241, 242 to the interrupter circuit 230 can be fixed to an H signal. Therefore, the inverter device 1 can achieve a state in which the safety function is disabled (non-operation mode) by the action of the changeover switch 250. In other words, the changeover switch 250 can switch between a state in which the safety function is enabled (operation mode) and a state in which the safety function is disabled (non-operation mode).

[0084] [Other embodiments] Next, other embodiments will be described.

[0085] The above-described embodiment may be modified or altered as appropriate.

[0086] For example, in the above embodiment, the emergency stop switch ES and the input terminals EN1, EN2 are connected by a signal line, but instead of the emergency stop switch ES, another device that outputs a safety signal may be connected. For example, the input terminals EN1, EN2 may be connected to a monitoring device that monitors the operating state of the motor M.

[0087] In addition, for example, in the above-described embodiment and examples of modifications and variations, the STO is provided as a safety function, but other safety functions may be provided instead of or in addition to the STO. The other safety functions may include, for example, a safe stop function (SS: Safe Stop) that stops the electric motor M while controlling its speed.

[0088] Also, for example, in the above-described embodiment and modified examples, the changeover switch 250 may open and close between the constant voltage power supply CVS and the signal lines on the output side of the input circuits 241, 242 in response to a user operation, with software intervening. For example, the control circuit unit 200 may switch the changeover switch 250 between ON and OFF when a predetermined function code is input via an input unit provided in the inverter device 1.

[0089] Also, for example, in the above-described embodiment and modified examples, the changeover switch 250 may switch the open / close state between the constant-voltage power supply CVS and the signal lines on the input side of the input circuits 241 and 242, instead of the open / close state between the constant-voltage power supply CVS and the signal lines on the output side of the input circuits 241 and 242. Specifically, the changeover switches 251 and 252 may be provided in the paths between the constant-voltage power supply CVS and the signal lines on the input side of the input circuits 241 and 242, i.e., the signal lines connected to the anodes of the photodiodes 241A1 and 242A1, respectively.

[0090] Also, for example, in the above-described embodiment and modified examples, the changeover switch 250 switches the connection state between the constant-voltage power supply CVS and the signal line on the input side or output side of the input circuit 240, but may switch the connection state of the signal path between the input circuit 240 and the cutoff circuit 230. That is, in the above-described embodiment, the changeover switch 250 switches whether the input circuit 240 accepts the signal input through the input terminals EN1 and EN2, but may switch whether the cutoff circuit 230 uses the signal accepted by the input circuit 240. Specifically, the changeover switch 251 may be configured as a double-throw type that can switch between a state in which the signal line on the output side of the input circuit 241 is connected to the input line of the cutoff circuit 230, and a state in which the signal line extending from the constant-voltage power supply CVS is connected to the input line of the cutoff circuit 230. In the operation mode, the changeover switch 251 may be in a state of connecting the signal line on the output side of the input circuit 241 and the input line of the cutoff circuit 230, and in the non-operation mode, the changeover switch 251 may be in a state of connecting the signal line extending from the constant-voltage power supply CVS and the input line of the cutoff circuit 230. Similarly, the changeover switch 252 may be configured as a double-throw type switch capable of switching between a state of connecting the signal line on the output side of the input circuit 242 and the input line of the cutoff circuit 230, and a state of connecting the signal line extending from the constant-voltage power supply CVS and the input line of the cutoff circuit 230. In the operation mode, the changeover switch 252 may be in a state of connecting the signal line on the output side of the input circuit 242 and the input line of the cutoff circuit 230, and in the non-operation mode, the changeover switch 252 may be in a state of connecting the signal line extending from the constant-voltage power supply CVS and the input line of the cutoff circuit 230. As a result, in the operation mode, the safety signal (L signal) input through the input terminals EN1 and EN2 is transmitted from the input circuit 240 to the shutoff circuit 230, and the inverter device 1 can achieve a state in which the safety function operates appropriately. On the other hand, in the non-operation mode, the signal input to the shutoff circuit 230 is fixed to an H signal, and the inverter device 1 can properly maintain a state in which the safety function does not operate.

[0091] Also, for example, in the above embodiment, the changeover switch 250 is provided for the input circuit 240 corresponding to the input terminals EN1 and EN2, but a similar changeover switch may be provided for the input circuits corresponding to the other input terminals. For example, a similar changeover switch may be provided for the input circuits corresponding to the other input terminals that can be connected to a signal line to which a signal used for a function other than the safety function or a signal for operating the other function is input.

[0092] Also, for example, in the above-described embodiment, the changeover switch 250 fixes the signal output from the signal line on the output side of the input circuits 241, 242 to an H signal, but it may also be configured to fix it to an L signal when the signal input from outside is an H signal.

[0093] Furthermore, for example, the configuration of the above-described embodiment (input terminals EN1, EN2, input circuit 240, and change-over switch 250, etc.) may be provided in another driving device that drives a load device other than the inverter device 1, such as a servo amplifier (an example of a driving device).

[0094] [Effect] Next, the operation of the inverter device 1 (control circuit section 200) according to this embodiment will be described with reference to FIG.

[0095] Fig. 3 is a diagram showing the configuration of an inverter device 1c according to a comparative example. Specifically, Fig. 3 is a diagram showing the state of the inverter device 1c in a non-operation mode in which a safety function related to the electric motor M does not operate.

[0096] In FIG. 3, the same components as those in the inverter device 1 according to the present embodiment are denoted by the same reference numerals.

[0097] As shown in FIG. 3, the inverter device 1c according to the comparative example is different from the inverter device 1 according to the present embodiment in that the change-over switch 250 is not provided. Therefore, in the inoperative mode of the safety function related to the electric motor M, the power supply terminal PLC and the input terminals EN1 and EN2 are connected by the short-circuit bar 250c. Also, instead of the short-circuit bar 250c, a jumper wire or the like may be used. This maintains a relatively high potential state of the input terminals EN1 and EN2, and the inverter device 1c can maintain a state in which an H signal is input to the input terminals EN1 and EN2. Therefore, the inverter device 1c can maintain a state in which an H signal is input from the input circuit 240 to the interrupter circuit 230, and can realize the inoperative mode of the safety function.

[0098] However, in the case of the inverter device 1c according to the comparative example, for example, assuming a non-operation mode of the safety function, it may become necessary to wire the shorting bar 250c, jumper wires, etc. between the power supply terminal PLC and the input terminals EN1, EN2 at the time of shipment from the factory. Therefore, the cost may increase due to the additional man-hours for wiring the shorting bar 250c, jumper wires, etc.

[0099] Furthermore, in the case of the inverter device 1c according to the comparative example, there is a risk of improper wiring due to human error in wiring the shorting bar 250c, jumper wire, etc. As a result, there is a possibility that the inverter device 1c cannot appropriately realize the inoperative mode of the safety function.

[0100] Furthermore, in the case of the inverter device 1c according to the comparative example, the shorting bar 250c, jumper wires, etc. may interfere with other wiring, which may deteriorate the workability of wiring work, and as a result, the production efficiency of the inverter device 1c may decrease.

[0101] Furthermore, in the case of the inverter device 1c according to the comparative example, in the safety function operation mode, the user may need to remove the shorting bar 250c, which may result in the user losing the shorting bar 250c.

[0102] In contrast, the inverter device 1 according to this embodiment includes input terminals EN1 and EN2, an input circuit 240, and a changeover switch 250. Specifically, the input terminals EN1 and EN2 are configured to be connectable to a predetermined signal line (for example, a signal line extending from an emergency stop switch ES) that transmits a predetermined signal (for example, a safety signal). The input circuit 240 is connected to the input terminals EN1 and EN2 and receives a signal input through the input terminals EN1 and EN2. The changeover switch 250 switches between a first state in which the input circuit 240 cannot receive a signal input through the input terminals EN1 and EN2, and a second state in which the input circuit 240 can receive a signal input through the input terminals EN1 and EN2. Alternatively, the changeover switch 250 switches between a first state in which the inverter device 1 (shutdown circuit 230) cannot use a signal received by the input circuit 240, or a second state in which the inverter device 1 (shutdown circuit 230) can use a signal received by the input circuit 240.

[0103] This eliminates the need to short-circuit between the power supply terminal PLC and the input terminals EN1 and EN2 using external wiring such as the short-circuit bar 250c or jumper wires, etc. Therefore, the inverter device 1 can omit external wiring connected to the input terminals EN1 and EN that are assumed to be unused.

[0104] In this embodiment, the changeover switch 250 may switch between a first state in which the potential of the input circuit 240 is maintained within a predetermined range (for example, a range of potentials corresponding to an H signal) and a second state in which the potential of the input circuit 240 can be changed according to the signals input from the input terminals EN1 and EN2. In other words, the changeover switch 250 may switch between a first state of the input circuit 240 equivalent to a state in which the input terminals EN1 and EN2 and the power supply terminal PLC are short-circuited, and a second state of the input circuit equivalent to a state in which the input terminals EN1 and EN2 and the power supply terminal PLC are not short-circuited.

[0105] As a result, the inverter device 1 can use the change-over switch 250 to switch between a first state in which the input circuit 240 cannot accept signals input through the input terminals EN1 and EN2, and a second state in which the input circuit 240 can accept signals.

[0106] In this embodiment, the inverter device 1 includes a signal utilization unit (e.g., interruption circuit 230) that utilizes a signal input through input terminals EN1 and EN2. The changeover switch 250 may switch between a first state in which the output line of the input circuit 240 and the input line of the signal utilization unit are interrupted, and a second state in which the output line of the input circuit 240 and the input line of the signal utilization unit are connected.

[0107] As a result, the inverter device 1 can use the change-over switch 250 to switch between, specifically, a first state in which the signal received by the input circuit 240 cannot be used, and a second state in which the signal received by the input circuit 240 can be used.

[0108] In this embodiment, signals used for a predetermined function of the inverter device 1 may be input to the input terminals EN1 and EN2 through a predetermined communication line.

[0109] This allows the inverter device 1 to switch the changeover switch 250 depending on whether a signal related to a predetermined function is required.

[0110] In addition, in this embodiment, the first state may correspond to a state in which a predetermined function (for example, a safety function) is disabled, and the second state may correspond to a state in which the predetermined function is enabled.

[0111] This allows the inverter device 1 to use the change-over switch 250 to switch between a first state (e.g., a non-operating mode) in which a predetermined function is disabled and a second state (e.g., an operating mode) in which the predetermined function is enabled.

[0112] In the present embodiment, the predetermined function may be a safety function (eg, STO) of a load device (motor M) driven by the main circuit section 100 of the inverter device 1.

[0113] Thereby, the inverter device 1 can use the change-over switch 250 to switch between a first state (non-operating mode) in which the safety function related to the motor M is disabled, and a second state (operating mode) in which the safety function is enabled.

[0114] In this embodiment, the changeover switch 250 may be mechanically switched between the first state and the second state by a user's operation.

[0115] This allows the inverter device 1 to switch between the first state and the second state with a simpler configuration.

[0116] Furthermore, in this embodiment, in the first state, the potential of the input circuit 240 may be maintained within a potential range corresponding to a high-level digital signal (H signal).

[0117] This allows the inverter device 1 to maintain the input circuit 240 not to accept the input of an L signal to be input from the input terminals EN1 and EN2 when the input terminals EN1 and EN2 are not in use.

[0118] Furthermore, in this embodiment, the changeover switch 250 may switch between an open and closed state of a connection line that connects a predetermined point of the input circuit 240 and a constant potential unit (for example, a constant voltage power supply CVS) in which the potential is maintained within a predetermined range.

[0119] As a result, the inverter device 1 can switch between a first state in which the potential of the input circuit 240 is maintained within a predetermined range and a second state in which the potential of the input circuit 240 can be changed in accordance with the signals input from the input terminals EN1 and EN2.

[0120] In this embodiment, the input circuit 241 may have a photocoupler 241A including a photodiode 241A1 connected to the input terminal EN1 by a signal line, and a phototransistor 241A2 connected to the output end by a signal line. Similarly, the input circuit 242 may have a photocoupler 242A including a photodiode 242A1 connected to the input terminal EN1 by a signal line, and a phototransistor 242A2 connected to the output end by a signal line. Then, the changeover switch 250 may be provided in a connection line connecting between a constant potential unit (constant voltage power supply CVS) and a signal line connecting the phototransistors 241A2, 242A2 and the output end.

[0121] As a result, the inverter device 1 can switch between a first state in which the potential of the input circuit 240 is maintained within a predetermined range and a second state in which the potential of the input circuit 240 can be changed in accordance with the signals input from the input terminals EN1 and EN2.

[0122] Although the embodiments have been described in detail above, the present disclosure is not limited to such specific embodiments, and various modifications and variations are possible within the scope of the gist described in the claims. [Explanation of symbols]

[0123] 1. Inverter device (drive device) 1H Case 100 Main circuit section 110 Rectifier circuit 120 smoothing circuit 122 Smoothing capacitor 124 Reactor 130 Inverter circuit 140 Charging circuit 142 Switch 144 Charging resistance 200 Control circuit section 210 Drive circuit 220 Control section 230 Breaking circuit (signal use section) 240,241,242 Input circuit 241A Photocoupler 241A1 Photodiode 241A2 Phototransistor 241B Input Resistance 242A Photocoupler 242A1 Photodiode 242A2 Phototransistor 242B Input Resistance 250 Changeover switch (changeover part) 251,252 Changeover switch ACIN AC input section ACOUT AC output section CPS Commercial power supply CVS constant voltage power supply (constant potential section) DCIN DC input section EN1, EN2 input terminals IPS internal power supply LT1, LT2 Reactor connection terminals M Electric motor (load device) N Negative DC terminal NL Negative Line P Positive DC terminal PL positive line PLC power terminal R,S,T AC input terminal U,V,W AC output terminal

Claims

1. An input terminal to which a predetermined signal line can be connected; an input circuit connected to the input terminal and configured to receive a signal input through the input terminal; a switching unit that switches between a first state in which the drive device cannot use a signal received by the input circuit and a second state in which the drive device can use a signal received by the input circuit; a signal utilization unit that utilizes a signal input through the input terminal, the switching unit switches between the first state in which the output line of the input circuit and the input line of the signal utilization unit are disconnected and the second state in which the output line of the input circuit and the input line of the signal utilization unit are connected. Drive unit.

2. An input terminal to which a predetermined signal line can be connected; an input circuit connected to the input terminal and configured to receive a signal input through the input terminal; a switching unit that switches between a first state in which the drive device cannot use the signal received by the input circuit and a second state in which the drive device can use the signal received by the input circuit, the switching unit switches between the first state in which the potential of the input circuit is maintained within the predetermined range and the second state in which the potential of the input circuit can be changed in accordance with the signal input from the input terminal, by switching an open / closed state of a connection line connecting a predetermined portion of the input circuit and a constant potential unit in which a potential is maintained within a predetermined range; the input circuit has a photocoupler including a photodiode connected to the input terminal by a signal line, and a phototransistor connected to an output terminal by a signal line; The predetermined portion is a signal line connecting the phototransistor and the output terminal. Drive unit.

3. The predetermined range is a range of potentials corresponding to a high-level digital signal. The drive device according to claim 2.

4. A signal used for a predetermined function of the drive device is input to the input terminal through the predetermined signal line. A drive arrangement according to any one of claims 1 to 3.

5. The first state corresponds to a state in which the predetermined function is disabled, and the second state corresponds to a state in which the predetermined function is enabled. The drive device according to claim 4.

6. The predetermined function is a safety function of a load device driven by a main circuit unit of the drive device. The drive device according to claim 5.

7. The switching unit mechanically switches between the first state and the second state in response to an operation by a user. A drive arrangement according to any one of the preceding claims.

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