JPH08234841A - Positioning operation abnormalty monitoring device - Google Patents

Abstract

PURPOSE: To enable speedy recovery by specifying the position of a fault. CONSTITUTION: This device is composed of a driving device 9 such as a motor for performing a positioning operation, detector 1 for converting the information of a position required for positioning to an electric signal, arithmetic unit 7 provided with a timer 8 for fetching the information of the detector 1 every fixed time, and controller 3 for performing an operation of forward rotation, backward rotation and stop of a motor 2 based on the arithmetic result of the arithmetic unit 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning operation abnormality monitoring device in a machine for positioning using a motor or the like.

[0002]

2. Description of the Related Art A conventional device of this type, as shown in FIG. 4, is a position detector 1 such as a potentiometer for converting position information into an electric signal, and a position display for receiving the signal from the detector 1 and displaying the position. It comprises a device 5 and a control device 3 which outputs an output for forward rotation or reverse rotation to the motor 2 in response to a signal from an input device such as a button for receiving a correction command from the operator.

The position of the object 4 to be positioned is converted into an electric signal amount such as voltage by the position detector 1 and displayed on the display device 5. As shown in FIG. 5, when the object 4 to be positioned is normally rotated by the motor 2, the position signal voltage increases,
The pointer of the display device 5 swings to the right. When the motor 2 is rotated in the reverse direction, the pointer of the display device 5 swings to the left. Assume that the target positioning position is when the pointer of the display device 5 is in the center. When the pointer is swung to the right from the center, the operator pushes the reverse push button of the operation switch 6 to operate so that the pointer comes to the center. When the pointer is biased to the left from the center due to overcorrection, the operator presses the forward rotation push button to operate the pointer so that it is centered, and positions it at the target position.

[0004]

In the conventional method, the operator performs positioning according to the display of the position detecting device, and in the case of a failure due to disconnection of the position detector, the operator pushes the push button without noticing it. Then, there was a danger that the object to be positioned could be moved to the limit of movement and the machine could be broken or the motor could be burned out. Further, the contact of the push button is welded, and the motor continues to rotate without any operation, which causes the above-mentioned danger. It is an object of the present invention to provide a positioning operation abnormality detection device that prevents these accidents in advance and also enables quick recovery by identifying the failure location.

[0005]

The structure of the present invention for achieving the above object is a drive device such as a motor for performing a positioning operation, a detector for converting position information necessary for positioning into an electric signal, and detection. It is characterized by comprising an arithmetic unit equipped with a timing device for taking in the information of the vessel at regular time intervals and a control unit for carrying out operations such as forward rotation, reverse rotation and stop of the motor according to the arithmetic result of the arithmetic unit. .

[0006]

According to the present invention, the position signal of the position detector is always taken into the arithmetic unit according to the signal from the timing device by the above-mentioned means at constant time intervals, and the rate of change of the position signal is calculated,
Compared to the state of the operation switch, a motor drive signal is given to the drive device, and compared with the state of the push button, the drive device is operated against an abnormal state such as when the change rate is positive or negative, or 0. Stop sending the signal to and issue an alarm.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. 1. A drive motor 2 and a position detector 1 thereof are attached to an object 4 to be positioned, and the position detector 1 and the motor 2 are attached.
Are connected to the control device 3, and the control device 3 includes an arithmetic unit 7
And a clock device 8 and a drive device, and the display device 5 and the operation switch 6 are connected to the arithmetic device 7.

Thus, as shown in FIG. 1, the arithmetic unit 7 in the control unit 3 receives a signal at regular time intervals by the clock unit 8 and takes in a position signal from the position detector 1. The taken-in position signal is sent to the display device 5, is displayed and the change rate is calculated, and compared with the state of the operation switch 6, a drive signal is sent to the drive device 9 to drive the motor 2. As shown in FIG. 2, if the rate of change of the position signal during normal rotation is expressed as positive, it is negative during reverse rotation and 0 during stop.

Then, as shown in FIG. 3, when the forward rotation push button is pressed, if the rate of change is within the specified range,
It is normal. At this time, when the rate of change became larger than the specified value (abnormal a), it was found that the number of rotations of the motor became large, and it seems that the load became light, so it can be determined that no-load operation is occurring. On the contrary, when the rate of change becomes smaller than the specified value, the load may have increased or the motor output may have decreased. Further, when the reverse rotation push button is pressed, the cause of abnormality due to the change rate corresponds to abnormality a ′ and abnormality b ′ and abnormality b ′, respectively.

Even if the stop push button is pressed, the rate of change becomes negative (abnormal c), which means that reverse rotation continues, and the welding of the contact for reverse rotation of the motor 2 in the drive unit 9 continues. is expected. When the rate of change is positive (abnormal c '), the opposite is expected. When the rate of change is reversed during normal rotation or reverse rotation (abnormal e, abnormal e ′),
It is expected that the polarities of the position detector 1 will be connected in reverse, or the command to the motor 2 will be connected in reverse, or the direction of rotation of the motor will be reversed.

[0011]

As described above, according to the present invention, the signal from the position detecting device is taken in and displayed on the display device, and the signal from the operation switch for forward, reverse and stop of the motor is taken in and after the arithmetic processing. By sending the control device to the motor drive device and taking in the position detection signal from the timer device at regular time intervals and monitoring the rate of change, it is possible to determine abnormalities such as overload on the motor 2 and burn out the motor. Can be prevented. Further, a runaway accident due to welding of contacts and the like can be dealt with in advance, and an accident due to an incorrect connection mistake when replacing or newly installing the position detector 1 can be prevented, and the cause of failure can be identified. By doing so, it is possible to shorten the recovery work in the event of an abnormality.

[Brief description of drawings]

FIG. 1 is a configuration diagram according to an embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between a change of a position signal and a change rate according to the embodiment of the present invention.

FIG. 3 is a diagram showing a relationship of a state of an operation switch of a position signal change rate at the time of abnormality.

FIG. 4 is a configuration diagram of a conventional example.

FIG. 5 is a relationship 1 between a position signal and a display device in a conventional example.
It is a figure showing an example.

[Explanation of symbols]

 1 Position Detector 2 Motor 3 Control Device 4 Positioned Object 5 Display Device 6 Operation Switch 7 Computing Device 8 Timing Device 9 Driving Device

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Claims (1)

[Claims] 1. A driving device such as a motor for performing a positioning operation, a detector for converting position information necessary for positioning into an electric signal, and a time measuring device for taking in the information of the detector at regular intervals. Depending on the arithmetic unit and the arithmetic result of the arithmetic unit,
A positioning operation abnormality monitoring device comprising a control device that performs operations such as normal rotation, reverse rotation, and stop of a motor.