JP7517968B2 - Control device - Google Patents

Description

The present invention relates to a control device that controls a motor.

The control device that controls the motor is powered by a commercial power source. Here, commercial power sources include those with low voltage (e.g., AC 100V) output and those with high voltage (e.g., AC 200V) output. When the motor is driven by high voltage power and a low commercial voltage is connected to the control device, a step-up transformer is provided in the control device to supply high voltage (e.g., 200V) power to the motor. In this case, if a high voltage commercial power source is mistakenly connected to a control device equipped with a step-up transformer, there is a risk of damaging the servo amplifier that supplies power to the motor to drive it. Meanwhile, Patent Document 1 shown below discloses a technology that uses fuses to prevent burnout of load equipment.

Japanese Patent Application Publication No. 7-255122

However, if a high-voltage commercial power source is mistakenly connected to a control device equipped with a step-up transformer, even if a fuse is simply used as in Patent Document 1 mentioned above, a voltage much higher than the high voltage (e.g., 400 V) will be supplied to the servo amplifier until the fuse blows. As a result, the servo amplifier will be damaged, and it is not necessarily easy to protect the drive system that supplies power to the motor from overvoltage.

The present invention aims to provide a control device that can protect a servo amplifier from overvoltage even if a high-voltage commercial power source is mistakenly connected to a control device equipped with a step-up transformer.

A control device according to one embodiment is a control device that uses an external power source to control the driving of at least a motor, and includes a first switch provided between the external power source and a motor drive device that drives the motor using power from the external power source and switches on and off a connection between the external power source and the motor drive device, a second switch provided between the first switch and the motor drive device and switches on and off a connection between the first switch and the motor drive device, a fuse provided between the first switch and the second switch, a step-up transformer provided between the fuse and the second switch, and a control unit that controls the first switch to be on and then controls the second switch to be on after a predetermined time has elapsed. The predetermined time is longer than the time required for the fuse to melt and break when power is supplied from the external power source having a second voltage higher than the first voltage.

According to the present invention, even if a high-voltage commercial power source is mistakenly connected to a control device equipped with a step-up transformer, the servo amplifier can be protected from overvoltage.

FIG. 2 is a diagram illustrating a control device according to an embodiment. 4 is a flowchart illustrating an example of an operation procedure of the control device according to the embodiment. 5 is a graph showing changes over time in a drive signal, a detection signal, and the voltage and current of a step-up transformer. FIG. 13 is a diagram illustrating a control device according to a comparative example. FIG. 13 is a diagram illustrating a control device according to a first modified example. FIG. 11 is a diagram illustrating a control device according to a second modified example.

The control device according to the embodiment is described in detail below.

FIG. 1 is a diagram showing a control device 10 according to an embodiment. The control device 10 has an electromagnetic contactor 12a, an electromagnetic contactor 12b, a fuse 14, a step-up transformer 16, a servo amplifier 18, a control unit 20, and an AC/DC converter 22. The control device 10 uses an external power source PS to control the driving of a machine device 30 (motor M). The machine device 30 is, for example, a multi-axis articulated robot, a machine tool, an injection molding machine, etc., which is operated by a motor M. Between the external power source PS and the servo amplifier 18, the electromagnetic contactor 12a, the fuse 14, the step-up transformer 16, and the electromagnetic contactor 12b are connected in series in the above order from the external power source PS side. The voltage from the external power source PS reaches the step-up transformer 16 via the electromagnetic contactor 12a and the fuse 14, is stepped up, and is applied to the servo amplifier 18 via the electromagnetic contactor 12b.

The external power source PS is, for example, a commercial power source that outputs AC voltage, and is detachably connected to the control device 10 via a connection part C0 to supply power to the control device 10. The connection part C0 is, for example, a combination of an outlet and a plug. The connection part C0 may be a combination of a terminal on the external power source PS side (for example, a terminal of a breaker connected to the external power source PS) and a terminal on the control device 10 side. The external power source PS is connected to the control device 10 by connecting the terminals on the external power source PS side and the control device 10 side to each other.

External power sources PS are generally classified into those that output a voltage V1 and those that output a voltage V2 that is greater than voltage V1. Voltage V1 is, for example, 100V to 120V AC, and voltage V2 is, for example, 200V to 230V AC, and these differ depending on the country or region. For example, voltages V1 and V2 are 100V AC and 200V AC in Japan, and 115V AC and 230V AC in the United States.

The AC/DC converter 22 converts the AC voltage V1 or voltage V2 into a predetermined DC voltage and supplies it as control power to the electromagnetic contactor 12a, the electromagnetic contactor 12b, the servo amplifier 18, and the control unit 20. As a result, the electromagnetic contactor 12a, the electromagnetic contactor 12b, and the control unit 20 can operate with either the external power supply PS of voltage V1 or voltage V2. However, it is assumed that the servo amplifier 18 needs to be supplied with power of voltage V2 to drive the motor M.

The electromagnetic contactor 12a and the electromagnetic contactor 12b are arranged to be connected in series between the external power supply PS and the servo amplifier 18, sandwiching the fuse 14 and the step-up transformer 16.

Each of the electromagnetic contactors 12a and 12b has a coil section 122, two contactors 124, and one contactor 126. The coil section 122 is controlled by the control unit 20 to be energized or not (in effect, the presence or absence of electromagnetic force), thereby switching the contactors 124 and 126 on and off. Here, when the coil section 122 is in a non-energized state, the contactor 124 is in an off state and the contactor 126 is in an on state, whereas when the coil section 122 is in an energized state, the contactor 124 is in an on state and the contactor 126 is in an off state. However, the relationship between the energization or non-energization of the coil section 122 and the on and off of the contactor 124 may be reversed. Also, the on and off of the contactor 124 and the contactor 126 may be aligned.

The two contactors 124 are connected to two wires L1 and L2 from the external power source PS, respectively, and switch between energizing and de-energizing the wires L1 and L2. However, only one contactor 124 may be provided, and it may be disposed on only one of the wires L1 and L2. The on/off state of the contactor 124 also means the on/off state of the electromagnetic contactor 12a (or the electromagnetic contactor 12b) itself. The contactor 126 is for detecting the on/off state of the contactor 124. A detection signal corresponding to the on/off state of the contactor 126 is output from the electromagnetic contactor 12a and the electromagnetic contactor 12b to the control unit 20. The detection signals corresponding to the on and off states of the contactor 126 are referred to as on and off signals (here, signals of levels L and H, respectively).

By turning on the electromagnetic contactor 12a, the electrical connection between the external power source PS and the step-up transformer 16 is turned on, and it is possible to turn on the electrical connection between the external power source PS and the servo amplifier 18. Since the electromagnetic contactor 12a and the electromagnetic contactor 12b are connected in series, when both are turned on, the electrical connection between the external power source PS and the servo amplifier 18 is turned on, and otherwise the electrical connection between the external power source PS and the servo amplifier 18 is turned off. The electromagnetic contactor 12a is provided between the external power source PS and the servo amplifier 18 (motor drive device) that drives the motor M using power from the external power source PS, and is controlled by the control unit 20. It functions as a first switch that switches the connection between the external power source PS and the servo amplifier 18 on and off.

By turning on the electromagnetic contactor 12b, the electrical connection between the step-up transformer 16 and the servo amplifier 18 is turned on, and the electrical connection between the external power supply PS and the servo amplifier 18 can be turned on. The electromagnetic contactor 12b is provided between the electromagnetic contactor 12a and the servo amplifier 18, and is controlled by the control unit 20, and functions as a second switch that switches the connection between the electromagnetic contactor 12a and the servo amplifier 18 on and off. In other words, the electromagnetic contactor 12b (second switch) is connected in series with the electromagnetic contactor 12a between the external power supply PS and the servo amplifier 18, and is provided closer to the servo amplifier 18 than the electromagnetic contactor 12a, and switches the connection between the external power supply PS and the servo amplifier 18 on and off.

The servo amplifier 18 operates using power from the step-up transformer 16 at voltage V2, and is controlled by the control unit 20 to drive the mechanical device 30, functioning as a drive device that drives the motor M. As described above, the servo amplifier 18 operates using voltage V2, and cannot operate using voltage V1.

The step-up transformer 16 is provided between the fuse 14 and the electromagnetic contactor 12b, and steps up the power supplied from the external power source PS and supplies it to the servo amplifier 18. When the external power source PS supplies power of voltage V1, the step-up transformer 16 steps up the voltage V1 to voltage V2. That is, voltage V1 is applied to the primary coil 162 of the step-up transformer 16, and voltage V2 is generated in the secondary coil 164.

When the external power source PS supplies power of voltage V2, the step-up transformer 16 is not necessary. For this reason, connections C1 and C2 are provided before and after the two fuses 14 and the step-up transformer 16 (hereinafter referred to as the step-up transformer 16, etc.), making it possible to disconnect the step-up transformer 16, etc. When the external power source PS supplies power of voltage V1, the step-up transformer 16, etc. is connected between the connection C1 and the connection C2, and the voltage V1 from the external power source PS is stepped up to voltage V2 and applied to the servo amplifier 18. On the other hand, when the external power source PS supplies power of voltage V2, the connection C1 and the connection C2 are directly connected without going through the step-up transformer 16, etc., and the voltage V2 from the external power source PS is applied directly to the servo amplifier 18.

Now, consider the case where the external power source PS supplies power of voltage V2 and this voltage V2 is applied to the step-up transformer 16. At this time, this voltage V2 is an overvoltage that is significantly larger than the original voltage V1 (standard voltage) at the primary coil 162 of the step-up transformer 16, and the step-up transformer 16 is saturated. This saturated state means that the magnetic flux density in the step-up transformer 16 is saturated and the impedance of the primary coil 162 of the step-up transformer 16 is significantly reduced. As a result, the current in the primary coil 162 of the step-up transformer 16 becomes excessive (occurrence of an overcurrent). If the step-up transformer 16 and the servo amplifier 18 are electrically connected (electromagnetic contactor 12b is on), an overvoltage (e.g., 400V) that is further boosted from the voltage V2 (e.g., 200V) is applied to the servo amplifier 18 from the secondary coil 164 of the step-up transformer 16. This overvoltage may damage the servo amplifier 18.

The two fuses 14 are provided between the electromagnetic contactor 12a and the electromagnetic contactor 12b to protect the servo amplifier 18 from overvoltage. As described above, when an overvoltage is applied to the step-up transformer 16 (for example, when the voltage V2 is applied to the primary coil 162), an overcurrent is generated and flows through the fuse 14. This overcurrent causes the fuse 14 to melt, thereby preventing the overvoltage from being applied to the servo amplifier 18. At this time, the time required for the fuse 14 to melt when power is supplied from the external power source PS at the voltage V2 is set as the melting time (time) ty. Here, the two fuses 14 are provided so as to correspond to the two wires L1 and L2 from the external power source PS. However, only one fuse 14 may be provided and placed on only one of the wires L1 and L2.

The control unit 20 controls the electromagnetic contactor 12a, the electromagnetic contactor 12b, and the servo amplifier 18. The control unit 20 can be configured by combining hardware (e.g., a processor) and software (e.g., a program). The control unit 20 has input terminals DI1, DI2 and output terminals DO1, DO2 corresponding to the electromagnetic contactor 12a and the electromagnetic contactor 12b. A drive signal that drives the coil portion 122 of the electromagnetic contactor 12a and the electromagnetic contactor 12b is output from the output terminal DO1 and the output terminal DO2, and the electromagnetic contactor 12a and the electromagnetic contactor 12b are turned on and off. The detection signals from the electromagnetic contactor 12a and the electromagnetic contactor 12b are input to the input terminals DI1 and DI2. In the following, the drive signals output from the output terminals DO1 and DO2 are referred to as drive signals DO1 and DO2, and the detection signals input to the input terminals DI1 and DI2 are referred to as detection signals DI1 and DI2.

The control unit 20 controls the servo amplifier 18 to drive the machine 30 (motor M). In addition, when the machine 30 (motor M) is to be stopped in an emergency during operation, the control unit 20 turns off both the electromagnetic contactor 12a and the electromagnetic contactor 12b. Even if there is a malfunction in either the electromagnetic contactor 12a or the electromagnetic contactor 12b, the motor M can be stopped reliably.

At startup, the control unit 20 checks the operation of the electromagnetic contactors 12a and 12b by sequentially changing the states of the electromagnetic contactors 12a and 12b from an OFF state to an ON state. In detail, the control unit 20 sequentially changes the states of the electromagnetic contactors 12a and 12b from an OFF state to an ON state using the drive signals D01 and DO2. The control unit 20 also checks, using the detection signals DI1 and DI2, that the states of the electromagnetic contactors 12a and 12b have changed, i.e., that the electromagnetic contactors 12a and 12b are capable of proper operation.

At this time, the control unit 20 turns on the electromagnetic contactor 12b after a time (elapsed time) tx has elapsed since the electromagnetic contactor 12a was turned on. This elapsed time tx is intended to ensure that the operation of the electromagnetic contactor 12a and the electromagnetic contactor 12b is confirmed. In other words, if the elapsed time tx is set to zero and both the electromagnetic contactor 12a and the electromagnetic contactor 12b are turned on at the same time, for example, a short circuit between the wiring that transmits the drive signal DO1 and the drive signal DO2 cannot be detected.

In this embodiment, the elapsed time tx from when the electromagnetic contactor 12a is turned on until the electromagnetic contactor 12b is turned on is set to be longer than the melting time ty of the fuse 14 (the time required for the fuse 14 to melt when the external power source PS of voltage V2 is connected). Therefore, if the external power source PS is of voltage V2, the fuse 14 melts during the period (time tx) when the electromagnetic contactor 12a is in the on state and the electromagnetic contactor 12b is in the off state. As a result, overvoltage is no longer applied to the servo amplifier 18. Note that the length of the elapsed time tx and the melting time ty may be set by adjusting either the elapsed time tx or the melting time ty (or both). For example, a fuse 14 with a short melting time ty may be used, or the elapsed time tx may be made longer.

(Operation of the control device 10)
The operation of the control device 10 according to the present embodiment will be described. FIG. 2 is a flow chart showing an example of the operation procedure of the control device 10 according to the embodiment. FIG. 3 is a graph showing the time changes of the drive signals DO1, DO2, the detection signals DI1, DI2, the voltages Vt1, Vt2, and the currents It1, It2 of the step-up transformer 16. The horizontal axis represents time, and the time changes of the drive signals DO1, DO2, the detection signals DI1, DI2, and the voltages Vt1, Vt2, and the currents It1, It2 of the primary coil 162 of the step-up transformer 16 are shown. The voltages Vt1, Vt2 correspond to the external power source PS of the voltage V1 and the external power source PS of the voltage V2, respectively. The currents It1, It2 also correspond to the external power source PS of the voltage V1 and the external power source PS of the voltage V2, respectively. Below, the operation procedure of the control device 10 will be described basically based on FIG. 2.

An external power supply PS is connected to the control device 10 (step ST1). In the configuration of this embodiment, the control device 10 has a step-up transformer 16, and an external power supply PS of voltage V1 should be connected. As mentioned above, if an external power supply PS of voltage V2 is connected to the control device 10, there is a risk that the servo amplifier 18 will be damaged by overvoltage. However, in this embodiment, even if an external power supply PS of voltage V2 is connected to the control device 10, damage to the servo amplifier 18 is prevented as follows.

The control device 10 connected to the external power source PS is started (step ST2). For example, the control device 10 is started by operating a start switch (not shown) of the control device 10.

At this start-up, the control unit 20 turns the electromagnetic contactor 12a on (step ST3). More specifically, the control unit 20 changes the electromagnetic contactor 12a from the off state to the on state by the drive signal DO1 (time t1 in FIG. 3). At this time, the control unit 20 confirms that the state of the electromagnetic contactor 12a has changed by the detection signal DI1 (specifically, that the detection signal DI1 has changed from an off signal (H level) to an on signal (L level)), that is, that the electromagnetic contactor 12a can operate properly. In reality, there is a slight time lag α between the drive signal DO1 and the detection signal DI1. That is, the change in the detection signal DI1 is delayed from the change in the drive signal DO1 by the time required for switching the electromagnetic contactor 12a. However, in FIG. 3, for ease of understanding, the time lag α is substantially zero. The same is true for the drive signal DO2 and the detection signal DI2.

If the connected external power supply PS is of voltage V1 ("V1" in step ST4), the fuse 14 does not melt due to overvoltage, and processing continues as is. That is, the control unit 20 turns on the electromagnetic contactor 12a and then turns on the electromagnetic contactor 12b after a time tx has elapsed (step ST5, time t2 in FIG. 3). In detail, the control unit 20 changes the electromagnetic contactor 12b from the OFF state to the ON state by the drive signal DO2 (time t2). At this time, the control unit 20 confirms that the state of the electromagnetic contactor 12b has changed by the detection signal DI2 (specifically, that the detection signal DI2 has changed from an OFF signal (H level) to an ON signal (L level)), that is, that the electromagnetic contactor 12b is capable of proper operation.

When both the electromagnetic contactor 12a and the electromagnetic contactor 12b are turned on, the step-up transformer 16 applies to the servo amplifier 18 the voltage V2, which is boosted from the voltage V1 (step ST6).

Then, the control unit 20 controls the servo amplifier 18 to drive the motor M (step ST7). Note that the control unit 20 turns off both the electromagnetic contactor 12a and the electromagnetic contactor 12b when the mechanical device 30 (motor M) is to be stopped in an emergency. Even if there is a malfunction in one of the electromagnetic contactor 12a or the electromagnetic contactor 12b, the motor M can be stopped reliably.

On the other hand, if the connected external power supply PS has a voltage V2 ("V2" in step ST4), the fuse 14 melts due to the overvoltage (step ST8, time t3 in FIG. 3). As a result, the servo amplifier 18 is protected from the overvoltage.

The melting time ty required for the fuse 14 to melt after the electromagnetic contactor 12a is turned on is shorter than the elapsed time tx from when the electromagnetic contactor 12a is turned on until the electromagnetic contactor 12b is turned on. Therefore, even if the connected external power source PS has a voltage of V2, an overvoltage is not applied to the servo amplifier 18.

In this embodiment, the following advantages can be enjoyed:

If the external power supply PS is of voltage V2, which should not be connected, the fuse 14 will blow, protecting the step-up transformer 16 and servo amplifier 18 from overvoltage.

The time ty required for fuse 14 to blow is shorter than the elapsed time tx required for electromagnetic contactors 12a and 12b to turn on in sequence, so fuse 14 blows before electromagnetic contactor 12b turns on. Therefore, even before fuse 14 blows, no overvoltage is applied to servo amplifier 18, improving the reliability of protection against overvoltage.

In the event of an emergency stop of the motor M, both the electromagnetic contactors 12a and 12b are turned off, so that the motor M can be stopped reliably even if there is a malfunction in one of them.

By sequentially turning on the electromagnetic contactors 12a and 12b at startup, it is possible to reliably protect the servo amplifier 18 from overvoltage while checking that the emergency stop electromagnetic contactors 12a and 12b are operating properly.

Comparative Example
A control device according to a comparative example will be described. Fig. 4 is a diagram showing a control device 10x according to the comparative example. In the control device 10x according to the comparative example, the fuse 14 and the step-up transformer 16 are connected to the rear stage of the electromagnetic contactor 12b, not between the electromagnetic contactor 12a and the electromagnetic contactor 12b.

Even in the control device 10x according to the comparative example, if the external power supply PS has a voltage V2 that should not be connected, the fuse 14 blows, thereby protecting the servo amplifier 18 to some extent from overvoltage.

However, in the control device 10x according to the comparative example, the voltage from the external power source PS is applied to the fuse 14 and the step-up transformer 16 after both the electromagnetic contactor 12a and the electromagnetic contactor 12b are turned on. Therefore, when the external power source PS of the voltage V2 is connected, an overvoltage (e.g., 400 V) that is further boosted from the voltage V2 (e.g., 200 V) by the step-up transformer 16 is applied to the servo amplifier 18 until the fuse 14 melts. In other words, the control device 10 according to the comparative example may lack protection for the servo amplifier 18 compared to the control device 10 according to the embodiment.

(Variation 1)
A control device 10 according to Modification 1 will be described. Fig. 5 is a diagram showing the control device 10 according to Modification 1. In the control device 10 according to Modification 1, two servo amplifiers 18 that drive two motors M are connected to the rear stage of the electromagnetic contactor 12b. That is, in Modification 1, the multiple servo amplifiers 18 can be protected from excessive voltage. Except for the above points, Modification 2 is not substantially different from this embodiment, and therefore a detailed description will be omitted.

(Variation 2)
A control device 10 according to Modification 2 will be described. Fig. 6 is a diagram showing the control device 10 according to Modification 2. In the control device 10 according to Modification 2, a servo amplifier 32 is connected to the rear stage of the electromagnetic contactor 12a. The machine device 30 has a motor Ma and a motor Mb driven by the servo amplifier 18 and the servo amplifier 32, respectively.

The servo amplifier 32 can operate with either voltage V1 or voltage V2, and has an amplifier main body 322, an input voltage determination unit 324, and a cutoff unit 326. The amplifier main body 322 uses voltage V1 or voltage V2 to control the drive of the motor Mb. The input voltage determination unit 324 determines whether the voltage of the external power supply PS is voltage V1 or voltage V2, and changes the settings of the amplifier main body 322 according to the determined voltage. The cutoff unit 326 is controlled by the control unit 20 to cut off the power supplied from the electromagnetic contactor 12a to the amplifier main body 322.

The control unit 20 controls the electromagnetic contactor 12a, the electromagnetic contactor 12b, the servo amplifier 18, and the servo amplifier 32.

The control unit 20 controls the servo amplifier 18 and the servo amplifier 32 to drive the mechanical device 30 (motors Ma, Mb).

When the mechanical device 30 (motors Ma, Mb) is to be stopped in an emergency, the control unit 20 turns off the electromagnetic contactor 12a, the cutoff unit 326, and the electromagnetic contactor 12b. Even if there is a malfunction in any of the electromagnetic contactor 12a, the cutoff unit 326, and the electromagnetic contactor 12b, the motors Ma and Mb can be stopped reliably.

At startup, the control unit 20 checks the operation of the electromagnetic contactor 12a, the cutoff unit 326, and the electromagnetic contactor 12b by sequentially changing the electromagnetic contactor 12a, the servo amplifier 32 (cutoff unit 326), and the electromagnetic contactor 12b from an OFF state to an ON state. In detail, the control unit 20 sequentially changes the electromagnetic contactor 12a, the cutoff unit 326, and the electromagnetic contactor 12b from an OFF state to an ON state by the drive signals D01, DO3, and DO2. The control unit 20 also checks, by the detection signals DI1, DI3, and DI2, that the states of the electromagnetic contactor 12a, the cutoff unit 326, and the electromagnetic contactor 12b have changed, i.e., that the electromagnetic contactor 12a, the cutoff unit 326, and the electromagnetic contactor 12b are capable of proper operation.

If the connected external power supply PS has a voltage V2, during this operation check, the fuse 14 melts within the elapsed time tx during which the electromagnetic contactor 12a is on and the electromagnetic contactor 12b is off. As a result, overvoltage is prevented from being applied to the servo amplifier 18. Except for the above points, there are no substantial differences between the second modification and this embodiment, so a detailed description will be omitted.

(Other Modifications)
In the embodiment and the modified example, the servo amplifiers 18 and 32 are included in the control device 10. Alternatively, the drive devices (servo amplifiers 18 and 32) may be separated from the control device 10, and the voltage V2 boosted by the step-up transformer 16 may be applied from the control device 10 to the servo amplifier 18.

[Modified embodiment]
Although the embodiments and modifications of the present invention have been described, the present invention is not limited to the above-mentioned embodiments and modifications, and various modifications are possible without departing from the gist of the present invention.

[Invention Obtained from the Embodiments]
The invention that can be understood from the above-described embodiment and modifications will be described below.

[1] The control device (10) is a control device that uses an external power source (PS) to control the driving of at least a motor (M), and includes a first switch (electromagnetic contactor 12a) that is provided between the external power source and a motor drive device (servo amplifier 18) that drives the motor using power from the external power source and switches on and off the connection between the external power source and the motor drive device, a second switch (electromagnetic contactor 12b) that is provided between the first switch and the motor drive device and switches on and off the connection between the first switch and the motor drive device, a fuse (14) provided between the first switch and the second switch, a step-up transformer (16) provided between the fuse and the second switch, and a control unit (20) that controls the first switch to be turned on and then controls the second switch to be turned on after a predetermined time (time tx) has elapsed. The predetermined time is longer than the time (time ty) required for the fuse to melt and cut when power is supplied from the external power source having a second voltage (voltage V2) that is higher than the first voltage (voltage V1). This allows the motor drive device to be protected from overvoltage when power is supplied from an external power source of the second voltage.

[2] The step-up transformer steps up the power supplied from the external power source at the first voltage to the second voltage and supplies it to the motor drive device. This makes it possible to operate a motor drive device rated at the second voltage using an external power source at the first voltage.

[3] The control device includes the motor drive device, and controls the motor drive by controlling the motor drive device. This makes it possible to protect the motor drive device included in the control device from overvoltage.

[4] The motor is a motor for moving a multi-axis, multi-joint robot. This allows the multi-axis, multi-joint robot to be controlled.

REFERENCE SIGNS LIST 10: control device 12a, 12b: electromagnetic contactor 14: fuse 16: step-up transformer 18: servo amplifier 20: control unit 30: mechanical device 122: coil section 124, 126: contactor M: motor PS: external power supply

Claims (4)

A control device that controls at least a motor drive using an external power source,
a first switch that is provided between the external power supply and a motor drive device that drives the motor using power from the external power supply and that switches on and off a connection between the external power supply and the motor drive device;
a second switch provided between the first switch and the motor drive device, the second switch switching on and off a connection between the first switch and the motor drive device;
a fuse provided between the first switch and the second switch;
a step-up transformer provided between the fuse and the second switch;
a control unit that controls the first switch to be turned on and then controls the second switch to be turned on after a predetermined time has elapsed;
Equipped with
The control device, wherein the predetermined time is longer than a time required for the fuse to melt and break when power is supplied from the external power supply having a second voltage higher than a first voltage. The control device according to claim 1 ,
The step-up transformer steps up the power supplied from the external power supply at the first voltage to the second voltage and supplies the power to the motor drive device. The control device according to claim 1 or 2,
The motor drive device is provided,
The control device controls the motor drive device, thereby controlling the driving of the motor. The control device according to any one of claims 1 to 3,
A control device, wherein the motor is a motor for moving a multi-axis, multi-joint robot.

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