JPS6172307A - Servomotor driver - Google Patents

Abstract

PURPOSE:To actuate an upper system with a machine device locked and to check the upper system without actuating the machine device by using an input cut-off switch device and an input display device. CONSTITUTION:When a switch device 7 is closed, a drive output (a) to be applied to a servomotor 1 is produced based on an input signal (c) given from an upper system 4 and an input signal (b) given from a sensor 2. Thus the motor 1 is driven. While an abnormal signal (d) is produced when the drive of the motor 1 is stopped and informed to the upper system. When the device 7is opened, it is inhibited that an input signal (c) given from the upper system is supplied to a servo driver main body 3'. At the same time, the state of the signal (c) is displayed on an input display device 8. Thus the signal (c) supplied to the main body 3' can be checked easily in an abnormal mode. Furthermore the upper system 4 can be started again after the signal (c) is cut off and the mobile part of a machine device is locked.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a servo driver (for driving a servo motor used as an actuator in machine tools, robots, etc.)
This invention relates to servo motor drive amplifiers) and is concerned with improving safety during maintenance and inspection of mechanical devices in which servo motors and servo drivers are incorporated.

Structure of conventional examples and their problems In general, mechanical devices using servo motors have a movable part that performs a predetermined work, and in order to increase work efficiency, the moving speed and force of the movable part are controlled by the "object" or It is often set as large as possible without interfering with the machine. Therefore, if a mechanical device operates suddenly and a person is within the moving range of the moving part of the mechanical device, the large power will cause an accident to be avoided. In some cases, accidents even lead to death.

Most of these accidents occur during maintenance and inspection of mechanical equipment, and further efforts are desired to ensure safety.

In the above-mentioned mechanical devices, the servo driver is used in combination with other parts, as shown in FIG. 3, for example.

In FIG. 3, 6 is a power source, 1 is a servo motor, and 2 is a tachogenerator attached to the shaft of the servo motor 1.

A sensor section such as an encoder, 3 a servo driver, 4 a host system that sends input signals to the servo driver 3, 5
is a safety device that cuts off the power to the servo driver 3 and stops the servo motor 1 in the event of an abnormality such as runaway of the servo motor I.

a is the drive output to the servo motor 1, b is the input signal from the sensor 2, C is the input signal from the host system 4 to the servo driver 3, and d is the input signal from the host system when the servo driver 3 stops operating for some reason. This is an abnormal signal to notify the terminal.

In the above configuration, the servo driver 3 generates a drive output a to the servo motor l based on the input signal C from the host system 4 and the input signal S from the sensor 2, and drives the servo motor l. Moreover, when the operation is stopped for some reason, an abnormality signal d is generated to notify the host system 4.

In the above configuration, if some abnormality occurs,
Mechanical equipment number 3
．． 92.3 If the operation stops, the cause can be removed relatively easily by checking the abnormal signal d from the servo driver 3 in Figure 3, but the cause may be related to the host system 4. In some cases, the mechanical equipment may be in a dangerous state where it is stopped without knowing when it will start working, and inspection requires a long wait.

However, if the power is turned off for safety reasons, the data at the time of the abnormality will be erased, making it difficult to investigate the cause, and currently inspections are unavoidably carried out with the power plugged in. Ta.

Purpose of the Invention The present invention facilitates inspection when a mechanical device using a servo motor or servo driver as described above is stopped due to an abnormality, and improves safety during inspection. The purpose is to provide a servo driver that can.

Structure of the Invention The servo driver of the present invention includes a servo driver main body that generates a drive output based on a first input signal from a sensor and a second input signal from a host system and supplies it to the servo motor; An input cutoff switch device provided at the input end of the second input signal of the servo driver main body, and an input display device provided on the host system side of the input cutoff switch device to display the state of the second input signal. The present invention is characterized by having a configuration including the following.

In this way, by providing an input cutoff switch device, the host system can be operated while the mechanical device is turned on, and the status of the input signal from the host system can be displayed, allowing the mechanical device to be operated. It is possible to check the host system without having to do so. Therefore, the mechanical equipment is less likely to work unnecessarily, and safety during inspection can be improved.

DESCRIPTION OF THE EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. 1 and 2. This servo driver is used in combination with other parts as shown in FIG.

In FIG. 1, the servo driver 9 is a servo driver main body 3' having the same function as the servo driver 3 in FIG.
It consists of a manual switch device 2i7, and a manual display device 8, and the connections with other parts are the same as in FIG. 3.

When the switch device V17 is closed, the servo driver 9 outputs a drive output a to the servo motor l based on the input signal C from the host system 4 and the input signal S from the sensor 2.
is generated to drive the servo motor l, and when the operation is stopped for some reason, an abnormality signal d is generated to notify the host system. Further, when the switch device 7 is opened, the input of the human power fJ No. C from the host system to the servo driver main body 3' is prevented, and the state of the input signal C is displayed on the input display device 8. It has become. C' is an input signal to the servo driver main body 3'.

FIG. 2 shows the specific configuration of the switch device 7 and the input display device 8, in which 7a is a changeover switch, 8a is a resistor, and 8b is a light emitting diode.

As a result of this configuration, it is possible to easily check the input signal C to the servo driver main body 3' in the event of an abnormality, and moreover, it is possible to easily check the input signal C to the servo driver main body 3'. Therefore, it is possible to check in advance at the signal level whether the required input signal C is being sent to the servo driver main body 3' without moving the mechanical device, and it is possible to restart the system 4 without moving the mechanical device. Since there is no need to restart the device and reproduce the abnormality, the possibility of personal injury during inspection can be reduced compared to when conventional servo drivers are used, increasing safety.

In the above embodiment, the light emitting diode 8b was used as the input display device 8, but devices other than the above, such as an ammeter, etc. can also be used. In this case, the level and scratchiness of the input signal C can also be displayed.

However, as an input display device, if the power to the servo driver 9 is cut off in the event of an abnormality, in order to display even when the power is cut off, a drive power source is not required, and the input display device is simply an input signal. It is necessary to make it visible and displayable. In a servo driver whose power is not cut off even in the event of an abnormality, any type of manual display device may be used. Further, if the human-powered display device is driven by a separate power source, there will be no problem even if the servo driver power source is cut off.

Effects of the Invention According to the present invention, the switch device is opened to cut off the input signal from the upper system stem to the servo driver main body, and the upper system is operated in a state where the mechanical device is locked, and the input signal from the upper system stem is cut off. Since the input display value Wt8 can be displayed, in the event of an abnormality, it is possible to test the operation of only the upper nostem first, thereby increasing safety during inspection.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a servo driver according to an embodiment of the present invention, FIG. 2 is a specific circuit diagram of main parts of the servo driver, and FIG. 3 is a circuit diagram of a conventional servo driver. 3'...Servo driver main body, 7...Switch device, 8...Input display device, 9...Servo driver (servo motor drive amplifier) Fig. 1 Fig. 2 Fig. 3

Claims (1)

[Claims] The first input signal from the sensor and the second input signal from the host system
a servo driver main body that generates a drive output based on an input signal and supplies it to the servo motor; an input cutoff switch device provided at the input end of the second input signal of the servo driver main body; A servo motor driver comprising: an input display device provided on a host system side of a cutoff switch device to display the state of the second input signal.