JP6747317B2 - Control device - Google Patents

Description

The present invention relates to a control device that controls the operation of a load.

A control device that controls the operation of a load including a power source, a display device, and the like according to an operation on a removable operation panel is known. The control device may have a function of emergency stop of the power source when the operation panel having the B contact emergency stop switch is detached. Patent Document 1 discloses a robot control device capable of invalidating an emergency stop of a robot when a control panel is detached. The robot controller makes an emergency stop of the robot when the operation panel is detached with the attachment/detachment switch turned off. The robot controller invalidates the emergency stop of the robot when the operation panel is detached while the attachment/detachment switch is turned on.

JP-A-5-42493

The robot controller invalidates the emergency stop even when the operation panel is mounted from the time when the attachment/detachment switch is turned on until the operation panel is detached. The robot controller cannot stop the robot when the user turns on the emergency stop switch during that time. Therefore, there is a problem that the robot control cannot be stably executed by the robot controller.

An object of the present invention is to provide a control device that can limit the function of an emergency stop when the operation panel is detached and can stably control the load.

A control device according to the present invention comprises a connecting portion for detachably connecting an operation panel having a normally-closed first contact for stopping the operation of a load, and an instruction portion for instructing detachment of the operation panel. In the control device for controlling the load according to an instruction from the operation panel, the connection unit connects a first terminal connected to the first contact and a second line connected to a signal line for detecting a connection state of the operation panel. A terminal, when there is no instruction to detach the operation panel from the instruction section and the operation panel is in a disconnected state, and when there is no instruction to detach the operation panel from the instruction section and the operation panel is When the operation of the first contact is detected via the first terminal in the connected state, the first control unit that stops the operation of the load at any time, and the detachment of the operation panel by the instruction unit When the operation panel is in the unconnected state, the second control section that does not limit the operation of the load, and the instruction section to detach the operation panel are present, and the operation panel is in the connected state. At the time, a third control unit that limits the operation of the load, and a first switching unit that switches whether to enable or disable the operation on the first contact are provided, and the first switching unit is the third The control unit enables the operation on the first contact before limiting the operation of the load, and disables the operation on the first contact after limiting the operation of the load by the third control unit. And

According to the present invention, the control device does not limit the operation of the load when there is an instruction to detach the operation panel from the instruction unit and the operation panel is in the unconnected state. Therefore, the user can continue the load operation by the control device even when the operation panel is not connected. The control device limits the operation of the load when there is an instruction to detach the operation panel from the instruction unit and the operation panel is in the connected state. When the load operation is limited, it is possible to suppress the occurrence of an event that causes the load to be stopped. Therefore, the control device can control the load in a stable state even when the function of stopping the load is disabled when the instruction unit instructs the removal of the operation panel.

Further, the control device enables the operation on the first contact until the operation of the load is limited. Therefore, the control device can stop the load in response to the operation on the first contact. The control device disables the operation on the first contact after limiting the operation of the load. Therefore, the control device can invalidate the load stop function according to the operation on the first contact while the load operation is limited.

In the present invention, the first switching unit invalidates an operation on the first contact until a predetermined time elapses after the operation of the load is restricted by the third control unit, and after the predetermined time elapses. The operation on the first contact may be effective. At this time, the control device can limit the period for invalidating the load stop function according to the operation on the first contact.

In the present invention, a limiting unit for limiting the operation of the load and a second switching unit for switching between validating and invalidating the limiting unit are provided, and the second control unit is the second switching unit. The operation of the load may not be restricted by disabling the restriction unit, and the third control unit may restrict the operation of the load by enabling the restriction unit by the second switching unit. At this time, the control device can easily switch between the time when the load operation is restricted and the time when the load operation is not restricted by the restriction unit.

In the present invention, whether the first switching unit enables or disables the operation on the first contact by switching whether to enable or disable the bypass circuit that bypasses the first contact. May be switched. At this time, the first switching unit can easily switch between enabling and disabling the operation on the first contact by the bypass circuit.

In the present invention, the second terminal includes one side connection terminal and the other side connection terminal, the connection portion, when the first distance from the operation panel, the operation via the one side connection terminal When the connection state of the panel becomes detectable, and the second distance between the operation panel and the first distance is shorter than the first distance, the first terminal is connected to the first contact and the space between the operation panel and the When the third distance is shorter than the second distance, the connection state of the operation panel may be detectable via the other-side connection terminal. At this time, the control device can limit the period during which the operation on the first contact is invalid to the period during which the operation panel is connected to the connection portion.

In the present invention, the second control unit may validate a plurality of operation commands for the load, and the third control unit may invalidate at least one of the plurality of operation commands. At this time, the control device can suppress the occurrence of the event that causes the emergency stop by controlling the operation of the load by the third control unit. Therefore, the control device can safely control the load.

The block diagram of control device 1A. The figure which shows the connection relation of the 1st contact 71, the 2nd contact 81, and the instruction|indication part 2. The figure which shows the operation mode of 1 A of control apparatuses. Flow chart showing the first main process Flow chart showing the second main process The block diagram of control device 1B. The figure which shows the operation mode of control device 1B. The block diagram of the modification of control device 1B. The block diagram of 1 C of control apparatuses. The figure which shows the connection part 3 and the connector 76. The flowchart of a 3rd main process.

<First embodiment>
A control device 1A according to the first embodiment will be described with reference to FIGS. 1 to 3. The control device 1A controls the operation of the load 9. A specific example of the load 9 is a motor. As a motor, there are a motor for rotating a tool and a motor for moving a work in a machine tool. The load 9 is not limited to the motor, and may be, for example, a high pressure turbine, a high voltage facility, a welding machine using high heat, a melting furnace, or the like. The user can control the operation of the load 9 via the control device 1A by operating the operation panel 8 provided in the control device 1A. The control device 1A detachably connects the operation panel 7A. The user can control the operation of the load 9 via the control device 1A by operating the operation panel 7A connected to the control device 1A. The control device 1A includes an instruction unit 2, a connection unit 3, a first switching unit 4, a control unit 5, and a control panel 8. The operation panel 7A includes a first contact 71 and a communication circuit 72.

<Instruction unit 2>
The instruction unit 2 includes normally open switches 2A, 2B, and 2C. The switches 2A, 2B, and 2C are interlocked with each other to switch to a conductive/non-conductive state. The switch 2A is connected to the first terminal 31A of the connection unit 3 described later via the switch 4A of the first switching unit 4 described below. The switch 2B is connected to the first terminal 31B of the connection unit 3 described later via the switch 4B of the first switching unit 4 described below. The switch 2C has one end connected to the reference potential 10 of the control device 1A and the other end connected to the CPU 51 and the state monitoring unit 52 described later. The user does not operate the instruction unit 2 when the user does not instruct to detach the operation panel 7A. At that time, the switches 2A, 2B, and 2C of the instruction unit 2 are turned off. The fact that the switches 2A, 2B, and 2C are in the non-conducting state is referred to as "the instruction unit 2 is turned off". The user operates the instruction unit 2 when instructing the detachment of the operation panel 7A. At that time, the switches 2A, 2B, and 2C of the instruction unit 2 are brought into conduction. The fact that the switches 2A, 2B, and 2C are in the conductive state is referred to as "the instruction unit 2 is turned on". The reason that the instruction unit 2 has the switches 2A, 2B, and 2C is that the state of the instruction unit 2 is accurately detected by duplication.

<First switching unit 4>
The first switching unit 4 includes switches 4A and 4B. The switch 4A is interposed between the switch 2A and the first terminal 31A. The switch 4B is interposed between the switch 2B and the first terminal 31B. The switches 4A and 4B are switched to either a conductive state or a non-conductive state in cooperation with each other in response to a control signal output from a state monitoring unit 52 described later. The fact that the switches 4A and 4B are in the non-conductive state is referred to as "the first switching unit 4 is turned off". When the switches 4A and 4B are in the conductive state is referred to as "the first switching unit 4 is turned on".

<Operation panel 8>
The operation panel 8 is permanently connected to the control device 1A. The operation panel 8 includes a second contact 81. The second contact 81 has normally closed switches 81A and 81B. The switches 81A and 81B are interlocked with each other to switch between a conductive state and a non-conductive state. The user does not operate the second contact 81 when the operation of the load 9 is not emergency stopped via the control device 1A. At this time, the switches 81A and 81B are brought into conduction. The user operates the second contact 81 when making an emergency stop of the operation of the load 9 via the control device 1A. At this time, the switches 81A and 81B are turned off. The reason that the second contact 81 has the switches 81A and 81B is that the state of the second contact 81 is accurately detected by duplication.

<Operation panel 7A>
Unlike the operation panel 8 described above, the operation panel 7A is detachably connected to the connection portion 3 described later. The operation panel 7A includes a first contact 71 and a communication circuit 72.

The first contact 71 has normally closed switches 71A and 71B. The switches 71A and 71B are interlocked with each other to switch between a conductive state and a non-conductive state. The user does not operate the first contact 71 when the operation of the load 9 is not emergency stopped via the control device 1A. At this time, the switches 71A and 71B are brought into conduction. The user operates the first contact 71 when making an emergency stop of the operation of the load 9 via the control device 1A. At this time, the switches 71A and 71B are turned off. The reason that the first contact 71 has the switches 71A and 71B is that the state of the first contact 71 is accurately detected by duplication.

The communication circuit 72 is an interface element for communicating with the control device 1A. The communication circuit 72 has an output terminal 72A and an input terminal 72B. The communication circuit 72 can output an operation command of the load 9 to the control device 1A via the output terminal 72A. The communication circuit 72 can detect the command output by the control device 1A via the input terminal 72B.

<Connecting part 3>
The connecting portion 3 is a connector for detachably connecting the operation panel 7A. The connection portion 3 includes first terminals 31A and 31B (collectively referred to as the first terminals 31), second terminals 32A and 32B (collectively referred to as the second terminals 32), and third terminals 33A and 33B (collectively referred to). And is referred to as a third terminal 33). A state in which the operation panel 7A is connected to the connection unit 3 is called a "connection state", and a state in which the operation panel 7A is not connected to the connection unit 3 is called an "unconnected state".

The first terminal 31A is connected to the switch 71A of the first contact 71 of the operation panel 7A when the operation panel 7A is in the connected state. The first terminal 31B is connected to the switch 71B of the first contact 71 of the operation panel 7A when the operation panel 7A is in the connected state. One end of each of the first terminals 31A and 31B is connected to the reference potential 10 of the control device 1A.

The second terminal 32 and the third terminal 33 are connected to the state monitoring unit 52 described later, respectively. The second terminals 32A and 32B are connected to the reference potential 70 of the operation panel 7A via the signal line when the operation panel 7A is in the connected state. Therefore, when the operation panel 7A is in the connected state, the reference potential 70 of the operation panel 7A and the state monitoring unit 52 are connected. The third terminal 33A is connected to the output terminal 72A of the communication circuit 72 when the operation panel 7A is in the connected state. The third terminal 33B is connected to the input terminal 72B of the communication circuit 72 when the operation panel 7A is in the connected state. Therefore, when the operation panel 7A is in the connected state, the communication circuit 72 and the state monitoring unit 52 are connected.

<Control unit 5>
The control unit 5 has a CPU 51, a state monitoring unit 52, an emergency stop circuit 53, and a storage unit 54. The CPU 51 controls the entire operation of the control device 1A. The CPU 51 is connected to the state monitoring unit 52, the emergency stop circuit 53, the storage unit 54, the switch 2C, and the load 9. The CPU 51 can detect ON/OFF of the instruction unit 2 via the switch 2C. When the operation panel 7A is in the connected state, the CPU 51 can control the operation of the load 9 according to the operation command received from the operation panel 7A via the state monitoring unit 52 described later. When the operation panel 7A is not connected, the CPU 51 can control the operation of the load 9 according to the operation command stored in the storage unit 54.

The state monitoring unit 52 is connected to the switch 2C and can detect ON/OFF of the instruction unit 2. The state monitoring unit 52 is connected to the second terminal 32 and can detect the connection state of the operation panel 7A. More specifically, the state monitoring unit 52 determines that the operation panel 7A is in the connected state when the second terminal 32 shows the reference potential 70, and the operation panel 7A when the second terminal 32 does not show the reference potential 70. Is determined to be unconnected. The state monitoring unit 52 is connected to the third terminal 33 and can communicate with the operation panel 7A in the connected state. The state monitoring unit 52 transfers the operation command received from the operation panel 7A to the CPU 51. The state monitoring unit 52 is connected to the first switching unit 4. The state monitoring unit 52 can switch on/off of the first switching unit 4 by outputting a control signal to the first switching unit 4.

The emergency stop circuit 53 is connected to the second contact 81 of the operation panel 8 and can detect the conduction state of the second contact 81. Although details will be described later, when the operation panel 7A is in the connected state, the emergency stop circuit 53 is connected to the first contact 71 of the operation panel 7A, and the conduction state of the first contact 71 can also be detected. The emergency stop circuit 53 is connected to the load 9. The emergency stop circuit 53 can stop the operation of the load 9 by stopping the power supply to the load 9 according to the states of the first contact 71 and the second contact 81. The storage unit 54 stores a program executed by the CPU 51 and a plurality of operation commands for controlling the load 9.

<Connection>
The connection relationship between the instruction unit 2, the first contact 71, the first switching unit 4, the second contact 81 and the emergency stop circuit 53 will be described with reference to FIG. When the operation panel 7A is in the connected state, the first contact 71 and the second contact 81 are connected in series, and the instruction unit 2 and the first contact 71 are connected in parallel via the first switching unit 4.

The connection relationship when the operation panel 7A is in the connected state will be described with reference to FIGS. The instruction unit 2 is on and the first switching unit 4 is off (a), the instruction unit 2 is off and the first switching unit 4 is on (b), the instruction unit 2 is off and the first switching unit 4 is off (c). In either case, that is, when at least one of the instruction unit 2 and the first switching unit 4 is off, the instruction unit 2 and the first switching unit 4 do not bypass the first contact 71. At that time, the first contact 71 and the second contact 81 are connected in series, and are interposed between the emergency stop circuit 53 and the reference potential 10. When the user does not operate either the first contact 71 or the second contact 81, the first contact 71 and the second contact 81 are in a conductive state, so that the emergency stop circuit 53 and the reference potential 10 are in a conductive state. Therefore, the emergency stop circuit 53 detects the reference potential 10. When the user operates at least one of the first contact 71 and the second contact 81, at least one of the first contact 71 and the second contact 81 operated by the user becomes non-conductive, and the emergency stop circuit 53. Then, the reference potential 10 becomes non-conductive. Therefore, the emergency stop circuit 53 does not detect the reference potential 10.

The emergency stop circuit 53 does not stop the operation of the load 9 when the reference potential 10 is detected, and stops the operation of the load 9 when the reference potential 10 is not detected. Therefore, when at least one of the instruction unit 2 and the first switching unit 4 is off (FIGS. 2A to 2C), the first contact 71 and the second contact 81 are contacted with each other in order to stop the load 9 in an emergency. Then, the emergency stop circuit 53 stops the operation of the load 9 in an emergency.

When the instruction unit 2 is on and the first switching unit 4 is on (d), the instruction unit 2 and the first switching unit 4 bypass the first contact 71. When the user does not operate the second contact 81, the emergency stop circuit 53 connects to the reference potential 10 via the indicator 2, the first switching unit 4, and the second contact 81. Even if the first contact 71 becomes non-conductive in response to the user operating the first contact 71, the emergency stop circuit 53 operates as a reference via the instruction unit 2, the first switching unit 4, and the second contact 81. Connect to potential 10. The emergency stop circuit 53 cannot detect the operation on the first contact 71. On the other hand, when the user does not operate the second contact 81, the second contact 81 becomes conductive, so that the emergency stop circuit 53 detects the reference potential 10. When the user operates the second contact 81, the second contact 81 is in a non-conducting state, so the emergency stop circuit 53 does not detect the reference potential 10.

Therefore, when both the instruction unit 2 and the first switching unit 4 are on (FIG. 2D), the operation performed on the first contact 71 to stop the load 9 in an emergency is invalid and the emergency stop circuit 53 Does not stop the operation of the load 9 in an emergency. On the other hand, the operation performed on the second contact 81 to stop the load 9 in an emergency is effective, and the emergency stop circuit 53 stops the operation of the load 9 in an emergency.

As described above, the first switching unit 4 can switch whether the operation performed on the first contact 71 is valid or invalid while the instruction unit 2 is turned on.

The connection relationship when the operation panel 7A is in the unconnected state will be described with reference to FIGS. When the operation panel 7A is in the unconnected state, the first terminal 31 is always in the non-conductive state. At this time, the instruction unit 2 is on and the first switching unit 4 is off (e), the instruction unit 2 is off and the first switching unit 4 is on (f), the instruction unit 2 is off and the first switching unit 4 is off. At any time of (g), that is, when at least one of the instruction unit 2 and the first switching unit 4 is off, the emergency stop circuit 53 and the reference potential 10 are always in a non-conductive state. Therefore, the emergency stop circuit 53 does not always detect the reference potential 10 regardless of the operation on the second contact 81. Therefore, when at least one of the instruction unit 2 and the first switching unit 4 is off (FIGS. 2E to 2G), the emergency stop circuit 53 emergency stops the operation of the load 9.

When the instruction unit 2 is on and the first switching unit 4 is on (h), the instruction unit 2 and the first switching unit 4 bypass the first terminal 31. At this time, the emergency stop circuit 53 is connected to the reference potential 10 via the instruction unit 2, the first switching unit 4, and the second contact 81. When the user does not operate the second contact 81, the second contact 81 becomes conductive, so that the emergency stop circuit 53 detects the reference potential 10. When the user operates the second contact 81, the second contact 81 is in a non-conducting state, so the emergency stop circuit 53 does not detect the reference potential 10. Therefore, when both the instruction unit 2 and the first switching unit 4 are turned on (FIG. 2(h)), the operation on the second contact 81 is enabled, and the emergency stop circuit 53 emergency stops the operation of the load 9.

<Operation mode>
The operation mode when the control device 1A controls the operation of the load 9 will be described with reference to FIG. The CPU 51 controls the operation of the load 9 by driving in the operation mode according to the presence/absence of the instruction to detach the operation panel 7A from the instruction unit 2 and the connection/non-connection of the operation panel 7A. The user operates the instruction unit 2 when instructing the detachment of the operation panel 7A. At this time, the instruction unit 2 is turned on. The user does not operate the instruction unit 2 when the user does not instruct to detach the operation panel 7A. At this time, the instruction unit 2 is turned off. Therefore, the CPU 51 drives in the operation mode according to the on/off state by the instruction unit 2 and the connected/unconnected state of the operation panel 7A, and controls the operation of the load 9. Details are as follows.

The CPU 51 limits the operation of the load 9 when the instruction unit 2 is on (the instruction to detach the operation panel 7A is given) and the operation panel 7A is in the connected state (see FIGS. 2A and 2D). More specifically, the CPU 51 invalidates at least a part of the plurality of operation commands of the load 9 received from the communication circuit 72 of the operation panel 7A via the third terminal 33. The operation mode of the control device 1A at that time is referred to as a restriction mode.

The CPU 51 does not limit the operation of the load 9 when the instruction unit 2 is off (no instruction to detach the operation panel 7A is given) and the operation panel 7A is in the connected state (see FIGS. 2B and 2C). More specifically, the CPU 51 validates all the plurality of operation commands of the load 9 received from the communication circuit 72 of the operation panel 7A via the third terminal 33. The operation mode of the control device 1A at that time is referred to as a normal mode.

The CPU 51 does not limit the operation of the load 9 when the instruction unit 2 is on (the instruction to detach the operation panel 7A is given) and the operation panel 7A is in the unconnected state (see FIGS. 2E and 2H). More specifically, the CPU 51 validates all the plurality of operation commands of the load 9 stored in the storage unit 54. The operation mode of the control device 1A at that time is the normal mode.

The CPU 51 operates the load 9 by the emergency stop circuit 53 when the instruction unit 2 is off (no instruction to detach the operation panel 7A is given) and the operation panel 7A is not connected (see FIGS. 2F and 2G). Emergency stop. The operation mode of the control device 1A at that time is referred to as an emergency stop mode. When the operation of the control device 1A enters the emergency stop mode, it does not return to other operation modes (normal mode, limit mode).

<First main processing>
The first main processing executed by the CPU 51 will be described with reference to FIG. The CPU 51 executes the program stored in the storage unit 54 to repeatedly execute the first main processing at a predetermined cycle (for example, 1 ms cycle).

The CPU 51 determines whether the instruction unit 2 is turned on by the switch 2C (S11). When the CPU 51 determines that the instruction unit 2 is on (the instruction to detach the operation panel 7A is present) (S11: YES) (see FIGS. 2A, 2D, and 2H), the process proceeds to S13. Although the details will be described later, when the instruction unit 2 is off (S11: NO) and the operation panel 7A is not connected (S23: NO), the CPU 51 drives in the emergency stop mode in S27 described later. As described above, the operation mode of the control device 1A does not return from the emergency stop mode to the normal mode. Therefore, since the first switching unit 4 is not turned off in S21 described later, the state of FIG.

The CPU 51 communicates with the state monitoring unit 52 and acquires information indicating the connected/unconnected state of the operation panel 7A detected by the state monitoring unit 52. Based on the acquired information, the CPU 51 determines whether the operation panel 7A is in the connected state (S13). When it is determined that the operation panel 7A is in the connected state (S13: YES) (see FIGS. 2A and 2D), the CPU 51 drives in the limit mode and limits the operation of the load 9 (S15). The CPU 51 advances the processing to S19. The CPU 51 communicates with the state monitoring unit 52 and outputs a control signal for turning on the first switching unit 4 from the state monitoring unit 52 (S19). As a result, the first switching unit 4 is turned on (see FIG. 2(d)). At this time, since the instruction unit 2 and the first switching unit 4 bypass the first contact 71, the operation performed on the first contact 71 is invalid. Therefore, even if the user operates the first contact 71 in order to make an emergency stop of the operation of the load 9, the emergency stop circuit 53 does not make an emergency stop of the operation of the load 9. The CPU 51 ends the first main process.

When the CPU 51 determines that the operation panel 7A is in the unconnected state (S13: NO) (see FIG. 2(h)), it drives in the normal mode and does not limit the operation of the load 9 (S17). At this time, since the instruction unit 2 is in the ON state (S11:YES) and the operation panel 7A is changing from the connected state (S13:YES) to the unconnected state (S13:NO), the first switching is performed by S19 described later. Part 4 is on. Therefore, since the state of FIG. 2E is not obtained, the emergency stop circuit 53 can perform the emergency stop of the load 9 when the user operates the second contact 81. The CPU 51 advances the processing to S19.

The CPU 51 communicates with the state monitoring unit 52 and outputs a control signal for turning on the first switching unit 4 from the state monitoring unit 52 (S19). As a result, the first switching unit 4 is turned on (see FIG. 2(h)). The CPU 51 ends the first main process.

When the CPU 51 determines that the instruction unit 2 is in the off state (no instruction to detach the operation panel 7A) (S11: NO), the process proceeds to S21 (FIGS. 2B, 2C, 2F). (See (g)). The CPU 51 communicates with the state monitoring unit 52 and outputs a control signal for turning off the first switching unit 4 from the state monitoring unit 52 (S21). As a result, the first switching unit 4 is turned off (see FIGS. 2(c) and 2(g)). The CPU 51 communicates with the state monitoring unit 52 and acquires information indicating the connected/unconnected state of the operation panel 7A detected by the state monitoring unit 52. Based on the acquired information, the CPU 51 determines whether the operation panel 7A is in the connected state (S23). When the CPU 51 determines that the operation panel 7A is in the connected state (S23: YES) (see FIG. 2C), it drives in the normal mode and does not limit the operation of the load 9 (S25). At this time, since the instruction unit 2 and the first switching unit 4 do not bypass the first contact 71, the operation performed on the first contact 71 is valid. Therefore, when the user operates the first contact 71 to stop the operation of the load 9 in an emergency, the emergency stop circuit 53 stops the operation of the load 9 in an emergency. The CPU 51 ends the first main process.

When it is determined that the operation panel 7A is not connected (S23: NO) (see FIG. 2G), the CPU 51 drives in the emergency stop mode. At that time, the emergency stop circuit 53 makes an emergency stop of the operation of the load 9 (S27). The CPU 51 ends the first main process.

<Operation and effect of the first embodiment>
The CPU 51 of the control device 1A operates in the normal mode when the instruction unit 2 issues an instruction to detach the operation panel 7A (S11: YES) and the operation panel 7A is not connected (S13: NO), and loads the load 9 Does not limit the operation of (S17). At this time, all the operation commands of the load 9 are valid. The CPU 51 can bypass the first terminal 31 by the instruction unit 2 and the first switching unit 4 by turning on the first switching unit 4 (S19). Therefore, even if the operation panel 7A is not connected, the user can invalidate the emergency stop function by the emergency stop circuit 53 and continue the operation of the load 9 by the control device 1A.

When there is an instruction to detach the operation panel 7A from the instruction unit 2 (S11: YES) and the operation panel 7A is in the connected state (S13: YES), the control device 1A drives the load 9 in the limit mode to operate the load 9. Restrict (S15). At this time, at least a part of the operation command of the load 9 is invalidated, so that it is possible to suppress the occurrence of an event that causes the load 9 to be stopped. Therefore, the control device 1A can control the load 9 in a stable state when the instruction unit 2 gives an instruction to detach the operation panel 7A.

After driving the CPU 51 in the restriction mode (S15), the first switching unit 4 is turned on (S19) and the first contact 71 is bypassed (FIG. 2(d)). At this time, the operation on the first contact 71 becomes invalid, and the emergency stop circuit 53 does not stop the operation of the load 9 even if the user operates the first contact 71. Furthermore, when the operation panel 7A is changed from the connected state to the unconnected state while being driven in the restriction mode, the first terminal 31 becomes the non-conductive state. However, since the first switching unit 4 is turned on and bypasses the first terminal 31 (FIG. 2(h)), the emergency stop circuit 53 does not detect the non-conduction state of the first terminal 31. Therefore, when the emergency stop circuit 53 is driven in the limit mode, the operation of the load 9 is not stopped even if the operation panel 7A is detached. That is, when the control device 1A is driven in the limited mode, the operation of the load 9 is not emergency stopped even if the user operates the first contact 71 of the operation panel 7A or detaches the operation panel 7A.

The CPU 51 does not bypass the first contact 71 by driving in the limit mode and limiting the operation of the load 9 (S15) until the first switching unit 4 is turned off (S21) (FIG. 2A). The operation on the first contact 71 is validated. Therefore, the emergency stop circuit 53 can stop the load 9 according to the operation on the first contact 71 until the operation of the load 9 is limited (S15). After the CPU 51 drives in the limit mode to limit the operation of the load 9 (S15), the first switching unit 4 is turned on (S19) to bypass the first contact 71 (FIG. 2(d)), and the first contact The operation for 71 is invalidated. Therefore, the control device 1A can invalidate the stop function of the load 9 according to the operation on the first contact 71 while the operation of the load 9 is limited.

When there is no instruction to detach the operation panel 7A from the instruction unit 2 (S11: NO), the CPU 51 turns off the first switching unit 4 (S21) and does not bypass the first contact 71 (FIG. 2(c)). .. At this time, the operation on the first contact 71 becomes effective. Therefore, the emergency stop circuit 53 can stop the operation of the load 9 according to the operation on the first contact 71 when the operation panel 7A is driven in the normal mode when the operation panel 7A is in the connected state (S25). Furthermore, when the operation panel 7A is changed from the connected state to the unconnected state during the operation in the normal mode, the first terminal 31 becomes the non-conductive state. Since the first switching unit 4 is turned off and the first terminal 31 is not bypassed (FIG. 2(g)), the emergency stop circuit 53 detects the non-conduction state of the first terminal 31. Therefore, when the emergency stop circuit 53 operates in the normal mode, the operation of the load 9 can be emergency stopped in response to the operation panel 7A being detached.

The first switching unit 4 can easily switch between a state in which the first contact 71 is bypassed and a state in which the first contact 71 is not bypassed when the user instructs the detachment of the operation panel 7A by the instruction unit 2 by turning on and off.

<Second embodiment>
The second embodiment is different from the first embodiment in that the CPU 51 executes the second main process instead of the first main process. The second main processing differs from the first main processing in the period during which the first switching unit 4 is turned off. The configuration of the control device 1A is the same as that of the first embodiment.

<Second main processing>
The second main processing executed by the CPU 51 will be described with reference to FIG. The same processing as the first main processing is given the same reference numeral to simplify the description. The CPU 51 determines whether the instruction unit 2 is on (S11). When the CPU 51 determines that the instruction unit 2 is on (there is an instruction to detach the operation panel 7A) (S11: YES), it determines whether the operation panel 7A is in the connected state (S13). When the CPU 51 determines that the operation panel 7A is in the unconnected state (S13: NO), it drives in the normal mode and does not limit the operation of the load 9 (S17). The CPU 51 resets the timer stored in the storage unit 54 by setting 0 (S37). The CPU 51 turns on the first switching unit 4 (S19, see FIG. 2(h)).

After the elapse of the predetermined period, the CPU 51 restarts the second main process. The case where the instruction unit 2 is turned on (S11: YES) and the operation panel 7A is changed from the unconnected state to the connected state is illustrated (S13: YES). At this time, the CPU 51 drives the load 9 in the limit mode (S15). The CPU 51 updates the timer stored in the storage unit 54 by adding 1 (S31). The CPU 51 determines whether the value of the timer is larger than a predetermined threshold value, thereby determining whether a predetermined time has elapsed since the timer was reset (S33). When the CPU 51 determines that the predetermined time has not elapsed (S33: NO), the process proceeds to S19. The CPU 51 turns on the first switching unit 4 (S19, FIG. 2D). The CPU 51 ends the second main processing. The CPU 51 repeatedly executes the second main processing. When the CPU 51 determines that the predetermined time has elapsed (S33: YES), it turns off the first switching unit 4 (S35, FIG. 2A). The CPU 51 ends the second main processing.

When the CPU 51 determines that the operation panel 7A is not connected (S11: NO), it drives in the normal mode or the emergency stop mode (S25, S27). The CPU 51 resets the timer by setting it to 0 (S39).

<Operation and effect of second embodiment>
The CPU 51 uses a timer to monitor whether a predetermined time has elapsed since the driving in the restriction mode was started (S33). The CPU 51 turns on the first switching unit 4 (S19) and bypasses the first contact 71 until the predetermined time passes (S33: NO) (FIG. 2(d)). At this time, the operation on the first contact 71 is invalid. Therefore, the emergency stop circuit 53 does not perform an emergency stop of the operation of the load 9 even if the user operates the first contact 71 until a predetermined time elapses after the restriction mode starts. After a predetermined time has elapsed (S33: YES), the CPU 51 turns off the first switching unit 4 (S35) and does not bypass the first contact 71 (FIG. 2(a)). At this time, the operation on the first contact 71 becomes effective. Therefore, the emergency stop circuit 53 causes the operation of the load 9 to be emergency stopped when the user operates the first contact 71 after a lapse of a predetermined time from the start of the restriction mode. Therefore, the control device 1A can limit the period during which the emergency stop function is disabled by bypassing the first contact 71 when driving in the limit mode.

<Third embodiment>
The control device 1B and the operation panel 7B in the third embodiment will be described with reference to FIGS. 6 and 7. The control device 1B is different from the first embodiment in that the control device 1B further includes a second switching unit 6 and the control unit 5 further includes a limiting unit 55. The operation panel 7B is different from the first embodiment in that the operation panel 7B further includes a third contact 73. Other configurations are the same as those in the first embodiment.

<Operation panel 7B>
As shown in FIG. 6, the operation panel 7B includes a third contact 73. The third contact 73 has normally open switches 73A and 73B. The switches 73A and 73B are interlocked with each other to switch between a conductive state and a non-conductive state. The user does not operate the third contact 73 when the restriction of the operation of the load 9 by the restriction unit 55 described later is effective. At this time, the switches 73A and 73B are turned off. The user operates the third contact 73 when invalidating the restriction of the operation of the load 9 by the restriction unit 55. At this time, the switches 73A and 73B become conductive. The reason why the third contact 73 has the switches 73A and 73B is to accurately detect the conductive state/non-conductive state of the third contact 73 by duplication.

<Control device 1B>
The connecting portion 3 further includes fourth terminals 34A and 34B (collectively referred to as fourth terminals 34). The fourth terminal 34A is connected to the switch 73A of the third contact 73 when the operation panel 7B is in the connected state. The fourth terminal 34B is connected to the switch 73B of the third contact 73 when the operation panel 7B is in the connected state. One end of the fourth terminal 34A is connected to the switch 6A described later, and one end of the fourth terminal 34B is connected to the switch 6B described later. The other ends of the fourth terminals 34A and 34B are connected to the reference potential 10 of the control device 1B, respectively.

The second switching unit 6 switches whether the restriction of the operation of the load 9 by the restriction unit 55 described later is valid or invalid. The second switching unit 6 includes switches 6A and 6B. The switch 6A is interposed between the fourth terminal 34A of the connection part 3 and a restriction part 55 described later. The switch 6B is interposed between the fourth terminal 34B of the connection section 3 and the restriction section 55. The switches 6A and 6B are interlocked with each other and switched to either a conductive state or a non-conductive state in accordance with a control signal output from the state monitoring unit 52. The non-conduction of the switches 6A and 6B is referred to as "the second switching unit 6 is turned off". When the switches 6A and 6B are in the conductive state is referred to as "the second switching unit 6 is turned on".

The limiting unit 55 limits the operation of the load 9 according to the state of the input terminal. The input terminal of the limiting unit 55 is connected to the second switching unit 6. When the operation panel 7B is in the connected state, the limiting section 55 connects to the third contact 73 via the second switching section 6. The input terminal of the limiting section 55 detects the reference potential 10 when the user operates the third contact 73 with the second switching section 6 turned on. At this time, the restriction on the operation of the load 9 by the restriction unit 55 becomes invalid. On the other hand, the input terminal of the limiting unit 55 does not detect the reference potential 10 when the second switching unit 6 is turned off or when the user does not operate the third contact 73 with the second switching unit 6 turned on. At this time, the restriction of the operation of the load 9 by the restriction unit 55 becomes effective.

When the user detaches the operation panel 7B from the control device 1B, one end and the other end of the fourth terminal 34A and one end and the other end of the fourth terminal 34B are short-circuited by a short cord (not shown). Therefore, the limiting unit 55 detects the reference potential 10 when the operation panel 7B is unconnected and the second switching unit 6 is on. At this time, the restriction on the operation of the load 9 by the control unit 55 becomes invalid. On the other hand, the limiting unit 55 does not detect the reference potential 10 when the operation panel 7B is unconnected and the second switching unit 6 is off. At this time, the restriction of the operation of the load 9 by the restriction unit 55 becomes effective.

<Operation mode>
The operation mode when the control device 1B controls the operation of the load 9 will be described with reference to FIG. Differences from the first embodiment are as follows.

The CPU 51 communicates with the state monitoring unit 52 when the instruction unit 2 is on (the instruction to detach the operation panel 7A is given) and the operation panel 7B is in the connected state (S11:YES, S13:YES, see FIG. 4), A control signal for turning off the second switching unit 6 is output from the state monitoring unit 52. The restriction of the operation of the load 9 by the restriction unit 55 is valid regardless of the operation on the third contact 73. Therefore, the control device 1B is driven in the limit mode (S15, see FIG. 4).

The CPU 51 communicates with the state monitoring unit 52 when the instruction unit 2 is off (no instruction to detach the operation panel 7A is given) and the operation panel 7B is in the connected state (S11:NO, S23:YES, see FIG. 4), A control signal for turning on the second switching unit 6 is output from the state monitoring unit 52. When the user operates the third contact 73 of the operation panel 7B, the restriction of the operation of the load 9 by the restriction unit 55 becomes invalid. Therefore, the control device 1B is driven in the normal mode (S25, see FIG. 4). On the other hand, when the user does not operate the third contact 73 of the operation panel 7B, the restriction of the operation of the load 9 by the restriction unit 55 is effective. Therefore, the control device 1B is driven in the limit mode (S25, see FIG. 4).

The CPU 51 communicates with the state monitoring unit 52 when the instruction unit 2 is on (the instruction to detach the operation panel 7A is given) and the operation panel 7B is not connected (S11:YES, S13:NO, see FIG. 4). , The control signal for turning on the second switching unit 6 is output from the state monitoring unit 52. The user short-circuits the fourth terminal 34 with a short cord (not shown). Therefore, the restriction of the operation of the load 9 by the restriction unit 55 becomes invalid. Therefore, the control device 1B is driven in the normal mode (S17, see FIG. 4). The emergency stop circuit 53 operates the load 9 when the instruction unit 2 is off (no instruction to detach the operation panel 7A is given) and the operation panel 7B is not connected (S11:NO, S23:NO, see FIG. 4). Emergency stop (S27, see FIG. 4).

<Operation and effect of third embodiment>
As described above, the control device 1B includes the restriction unit 55 that restricts the operation of the load 9, and the second switching unit 6 that switches whether the restriction of the operation of the load 9 by the restriction unit 55 is valid or invalid. .. The CPU 51 turns off the second switching unit 6 when the instruction unit 2 is on (the instruction to detach the operation panel 7A is given) and the operation panel 7B is in the connected state. At this time, the restriction of the operation of the load 9 by the restriction unit 55 becomes effective, so the control device 1B is driven in the restriction mode. The CPU 51 turns on the second switching unit 6 when the instruction unit 2 is off (no instruction to detach the operation panel 7A is given) and the operation panel 7A is in the connected state. At this time, the user operates the third contact 73 of the operation panel 7B to invalidate the restriction of the operation of the load 9 by the restriction unit 55, and the control device 1B is driven in the normal mode. Therefore, the control device 1B can easily switch between the time when the operation of the load 9 is restricted and the time when the operation of the load 9 is not restricted by the restriction unit 55 and the second switching unit 6.

<Modification of Third Embodiment>
As shown in FIG. 8, the instruction unit 2 of the control device 1B may further include switches 2D and 2E. At this time, the switch 2D is connected in parallel with the fourth terminal 34A, and the switch 2E is connected in parallel with the fourth terminal 34B. The switch 2D opens the fourth terminal 34A in the non-conductive state, and short-circuits the fourth terminal 34A in the conductive state. The switch 2E opens the fourth terminal 34B in the non-conductive state, and short-circuits the fourth terminal 34B in the conductive state. The switches 2D and 2E are interlocked with the other switches 2A, 2B, and 2C of the instruction unit 2 to switch to either a conductive state or a nonconductive state. The switches 2D and 2E become non-conducting when the indicator 2 is turned off. The switches 2D and 2E become conductive when the indicator 2 is turned on.

The CPU 51 communicates with the state monitoring unit 52 when the instruction unit 2 is on (the instruction to detach the operation panel 7A is given) and the operation panel 7B is not connected (S11:YES, S13:NO, see FIG. 4). , The control signal for turning on the second switching unit 6 is output from the state monitoring unit 52. Since the indicator 2 is turned on, the fourth terminal 34 is short-circuited by the switches 2D and 2E. Therefore, the restriction of the operation of the load 9 by the restriction unit 55 becomes invalid. Therefore, the control device 1B is driven in the normal mode (S17, see FIG. 4).

The CPU 51 communicates with the state monitoring unit 52 when the instruction unit 2 is on (the instruction to detach the operation panel 7A is given) and the operation panel 7B is in the connected state (S11:YES, S13:YES, see FIG. 4), A control signal for turning off the second switching unit 6 is output from the state monitoring unit 52. Therefore, even if the fourth terminal 34 is short-circuited by the switches 2D and 2E, the restriction of the operation of the load 9 by the restriction unit 55 is effective. Therefore, the control device 1B is driven in the limit mode (S15, see FIG. 4).

<Fourth Embodiment>
A control device 1C and an operation panel 7C in the fourth embodiment will be described with reference to FIGS. 9 to 11. The control device 1C is different from the first embodiment in that the instruction unit 2 does not have the first switch 2C and that the second terminal 32 of the connection unit 3 has the one side terminal 321 and the other side terminal 322.

<Control device 1C>
As shown in FIG. 9, the instruction unit 2 of the control device 1C has switches 2A and 2B in a short-circuited state. That is, since the switches 2A and 2B are always in the conductive state, the instruction unit 2 is always turned on. The instruction unit 2 does not have the switch 2C in the control device 1A. The second terminal 32 of the connecting portion 3 has one side terminal 321 and the other side terminal 322. When the operation panel 7C is in the connected state, the one side terminal 321 and the other side terminal 322 are connected to the reference potential 70 of the operation panel 7C, respectively. The one-side terminal 321 and the other-side terminal 322 are connected to the state monitoring unit 52, respectively. The state monitoring unit 52 can determine whether the operation panel 7C is in the connected state by the one side terminal 321 and the other side terminal 322.

<Operation panel 7C>
As shown in FIG. 10, the operation panel 7C has a connector 76 that connects to the connecting portion 3 of the control device 1C. The connector 76 has a connection terminal 761 connected to the first terminal 31, a connection terminal 771 connected to the one side terminal 321, and a connection terminal 772 connected to the other side terminal 322. The connection terminal connected to the third terminal 33 is omitted. As shown in FIG. 9, the connection terminal 761 is connected to the first contact 71 of the operation panel 7C. The connection terminals 771 and 772 are connected to the reference potential 70 of the operation panel 7C.

As shown in FIG. 10, the connection terminals 761, 771, 772 have different lengths. The connecting terminal 771 has the longest length and the connecting terminal 772 has the shortest length. Therefore, when the connector 76 is connected to the connecting portion 3 of the control device 1C to bring the operation panel 7C into the connected state, the connecting terminals 761, 771, 772 are connected to the connecting portion 3 at different times. More specifically, when the distance between the control device 1C and the operation panel 7C is the predetermined first distance, the connection terminal 771 is connected to the one-side terminal 321. When the distance between the operation panel 7C and the connector 76 is the predetermined second distance shorter than the first distance, the connection terminal 761 is connected to the first terminal 31. When the distance between the operation panel 7C and the connector 76 is a predetermined third distance shorter than the second distance, the connection terminal 772 is connected to the other side terminal 322.

Therefore, when the distance between the operation panel 7C and the control device 1C is the first distance, the operation panel 7C is in the connection state depending on whether or not the state monitoring unit 52 detects the reference potential 70 via the one-side terminal 321. Can be detected. When the distance between the operation panel 7C and the control device 1C is the second distance, the emergency stop circuit 53 can detect whether the first contact 71 is operated via the first terminal 31. When the distance between the operation panel 7C and the control device 1C is the third distance, the state monitoring unit 52 determines whether the operation panel 7C is in the connected state depending on whether or not the reference potential 70 is detected via the other-side terminal 322. It becomes detectable. Hereinafter, when the state monitoring unit 52 detects the reference potential 70 via the one-side terminal 321 and the other-side terminal 322, it is referred to as “one-side terminal 321 turns on” and “the other-side terminal 322 turns on”, respectively. When the state monitoring unit 52 does not detect the reference potential 70 via the one-side terminal 321 and the other-side terminal 322, it is said that “one-side terminal 321 turns off” and “the other-side terminal 322 turns off”, respectively.

<Third main processing>
The third main processing executed by the CPU 51 will be described with reference to FIG. The description of the same processing as the second main processing will be simplified. The CPU 51 communicates with the state monitoring unit 52 and acquires the state of the other terminal 322 detected by the state monitoring unit 52. The CPU 51 determines whether the other terminal 322 is off based on the acquired information (S51). When the CPU 51 determines that the other terminal 322 is off (S51: YES), the process proceeds to S53. At this time, the distance between the operation panel 7C and the control device 1C is larger than the third distance.

The CPU 51 communicates with the state monitoring unit 52 and acquires the state of the one-side terminal 321 detected by the state monitoring unit 52. The CPU 51 determines whether the one-side terminal 321 is on based on the acquired information (S53). When the CPU 51 determines that the one-side terminal 321 is on (S53: YES), the process proceeds to S55. At this time, the distance between the operation panel 7C and the control device 1C is smaller than the first distance. Therefore, since the connection terminal 761 of the operation panel 7C is connected to the first terminal 31, the operation panel 7C is in the connected state. The CPU 51 drives in the restriction mode (S55).

The CPU 51 updates the timer stored in the storage unit 54 by adding 1 (S57). The CPU 51 determines whether the value of the timer is larger than a predetermined threshold value to determine whether a predetermined time has elapsed since the timer was reset (S59). When the CPU 51 determines that the predetermined time has not elapsed (S59: NO), the process proceeds to S69. The CPU 51 turns on the first switching unit 4 (S69). Since the instruction unit 2 is always turned on, the instruction unit 2 and the first switching unit 4 bypass the first terminal 31. Therefore, the emergency stop circuit 53 does not detect the operation of bringing the operation panel 7A into the unconnected state. The CPU 51 ends the third main processing.

When determining that the predetermined time has passed (S59: YES), the CPU 51 turns off the first switching unit 4 (S61). At this time, the instruction unit 2 and the first switching unit 4 do not bypass the first terminal 31. Therefore, the emergency stop circuit 53 can detect the operation of bringing the operation panel 7A into the unconnected state and can stop the driving of the load 9 in response to the operation. Since the state in which the other-side terminal 322 is off and the one-side terminal 321 is on continues for a predetermined time, there is a possibility that the connection of the connector 76 to the connecting portion 3 is insufficient. The CPU 51 notifies the user that an abnormal connection of the connector 76 has occurred (S63). The CPU 51 ends the third main processing.

When the CPU 51 determines that the one-side terminal 321 is off (S53: NO), the process proceeds to S65. At this time, the distance between the operation panel 7C and the control device 1C is larger than the first distance. Therefore, the connection terminal 761 of the operation panel 7C is not connected to the first terminal 31, and the operation panel 7C is in the unconnected state. The CPU 51 drives in the normal mode (S65). The CPU 51 resets the timer by setting it to 0 (S67). The CPU 51 turns on the first switching unit 4 (S69). Since the instruction unit 2 is always turned on, the instruction unit 2 and the first switching unit 4 bypass the first terminal 31. Therefore, the emergency stop circuit 53 does not detect the operation of bringing the operation panel 7A into the unconnected state. The CPU 51 ends the third main processing.

When the CPU 51 determines that the other terminal 322 is on (S51: NO), the first switching unit 4 is turned off (S71). At this time, the distance between the operation panel 7C and the control device 1C is smaller than the third distance. Therefore, since the connection terminal 761 of the operation panel 7C is connected to the first terminal 31, the operation panel 7C is in the connected state. The CPU 51 determines whether the one-side terminal 321 is on (S73). When the CPU 51 determines that the one-side terminal 321 is on (S73: YES), it drives in the normal mode (S75). The CPU 51 advances the processing to S79. When the CPU 51 determines that the one-sided terminal 321 is off (S73: NO), the other-sided terminal 322 is on and the one-sided terminal 321 is off. Therefore, the connector 76 is distorted with respect to the connection part 3, and the pin of the connection part 3 is broken. , There is a possibility that the connection is made in the state where the contact failure due to the adhered matter has occurred. The CPU 51 notifies the user that an abnormal connection of the connector 76 has occurred (S77). The CPU 51 advances the processing to S79. The CPU 51 initializes the timer stored in the storage unit 54 by setting 0 (S79). The CPU 51 ends the third main processing.

<Operation and effect of the fourth embodiment>
In the control device 1C, when the connector 76 of the operation panel 7C is brought close to the connection portion 3 to be connected, the one side terminal 321 is first turned on, then the first contact 71 is connected to the first terminal 31, and then the other side. The terminal 322 turns on. Therefore, the CPU 51 turns on the first switching unit 4 to bypass the first contact 71 and invalidates the operation on the first contact 71 while the one side terminal 321 is on and the other side terminal 322 is off. When both the one-side terminal 321 and the other-side terminal 322 are turned on, the CPU 51 turns off the first switching unit 4 and bypasses the first contact 71, and enables the operation on the first contact 71. At this time, the CPU 51 can limit the period for bypassing the first contact 71 by the instruction unit 2 and the first switching unit 4 to the period for connecting the connector 76 to the connecting unit 3. Therefore, the control device 1C can minimize the period during which the operation on the first contact 71 is invalid.

<Modification>
The present invention is not limited to the above embodiment, and various modifications can be made. The control unit 5 may be configured by a device in which the CPU 51, the state monitoring unit 52, the emergency stop circuit 53, and the storage unit 54 are integrated. Each of the first contact 71, the second contact 81, the instruction unit 2, the first switching unit 4, and the second switching unit 6 may have one switch. The indicator 2 is not limited to the normally open type switch, but may be a normally closed type switch. The indicator 2 does not have to be a switch, but may be a terminal that switches between a short-circuited state and a non-short-circuited state. The operation panels 7A, 7B, 7C may have a short-circuit terminal that turns on the indicator 2 when connected to the connector 3. At this time, the instruction unit 2 may be turned on when the operation panels 7A, 7B, 7C are in the connected state.

The emergency stop circuit 53 may output a control signal to the CPU 51 instead of stopping the operation of the load 9 in an emergency. When the CPU 51 detects the control signal output from the emergency stop circuit 53, the CPU 51 may display notification information on a display unit (not shown). The first to third main processing is not limited to the case where the CPU 51 realizes the processing based on a program. The first to third main processing may be executed by hardware by a logic circuit or the like. When the control devices 1A, 1B, 1C operate in the restricted mode, it is not limited to invalidating a part of the plurality of operation commands. For example, when the control devices 1A, 1B, 1C operate in the restriction mode, all operations for controlling the operation of the load 9 that are operations on the operation panels 7A, 7B, 7C may be invalidated.

The control devices 1A, 1B, 1C may not have the operation panel 8. The user may emergency stop the operation of the load 9 by operating the first contact 71 of the operation panel 7A, 7B, 7C. The control devices 1A, 1B, 1C may not have the first switching unit 4. At this time, the first contact 71 may be bypassed by turning on the instruction unit 2. The operation panels 7A, 7B, 7C may not have the communication circuit 72. In the fourth example, the second terminal 32A of the second terminal 32 in the first embodiment may be used as one side terminal and the second terminal 32B may be used as the other side terminal.

1A, 1B, 1C: Control device 2: Instruction part 3: Connection part 4: First switching part 5: Control part 6: Second switching parts 7A, 7B, 7C: Operation panel 9: Load 10: Reference potential 31: No. One terminal 32: Second terminal 33: Third terminal 34: Fourth terminal 51: CPU
52: State monitoring unit 53: Emergency stop circuit 54: Storage unit 55: Limiting unit 71: First contact 321: One side terminal 322: Other side terminal

Claims (6)

A connection part for detachably connecting an operation panel having a normally-closed first contact for stopping the operation of the load, and an instruction part for instructing detachment of the operation panel are provided. In the control device for controlling the load,
The connection portion includes a first terminal connected to the first contact and a second terminal connected to a signal line that detects a connection state of the operation panel,
When there is no instruction to detach the operation panel from the instruction unit and the operation panel is in a non-connection state, and when there is no instruction to detach the operation panel from the instruction unit and the operation panel is in a connection state At any time when the operation of the first contact is detected via the first terminal, a first control unit that stops the operation of the load,
When there is an instruction to detach the operation panel from the instruction section and the operation panel is not connected, a second control section that does not limit the operation of the load,
When there is an instruction to detach the operation panel from the instruction section and the operation panel is in a connected state, a third control section that limits the operation of the load ,
A first switching unit that switches between enabling and disabling the operation on the first contact;
Equipped with
The first switching unit,
The operation on the first contact is validated before the operation of the load is restricted by the third controller, and the operation on the first contact is disabled after the operation of the load is restricted by the third controller. A control device characterized by the above. The first switching unit,
The operation on the first contact is disabled until a predetermined time elapses after the operation of the load is limited by the third control unit, and the operation on the first contact is enabled after the predetermined time elapses. The control device according to claim 1 , wherein: A limiter for limiting the operation of the load, and a second switcher for switching between enabling and disabling the limiter,
The third control unit,
The control device according to claim 1 or 2 , wherein the second switching unit enables the limiting unit to limit the operation of the load. The first switching unit,
By the switching the whether to enable or disable the bypass circuit which bypasses the first contact, the preceding claims, characterized in that switching between whether to enable or disable the operation to the first contact The control device according to any one of 3 above. The second terminal includes one side connection terminal and the other side connection terminal,
The connection is
When the distance between the operation panel and the first distance, the connection state of the operation panel can be detected via the one side connection terminal,
When the second distance between the operation panel and the first distance is shorter than the first distance, the first terminal is connected to the first contact,
When between the operation panel is short third distance greater than the second distance, of claims 1 to 4, wherein the connection state via the other-side connecting terminals the operation panel is characterized in that it is possible to detect The control device according to any one of claims. The second control unit validates a plurality of operation commands for the load,
The third control unit, the control device according to any one of claims 1-5, characterized in that for disabling said at least one of the plurality of operation command.

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