JPH04120603A - Pc-nc device - Google Patents

Abstract

PURPOSE:To simplify the sequence and a starting and completing programs by providing a relay to be exclusively used for detecting movement completion immediately before a drive instruction to a servo motor and detecting the movement completion of the servo motor from the contact signal of the relay. CONSTITUTION:Movement of a servo motor is started by giving a servo motor driving instruction to a driver circuit 8 when the coil signal of an F relay rises. Then the contact signal of the F relay is turned on when the movement of the servo motor is completed. As a result, the F relay makes operations in such a state that the contact signal is delayed from the coil signal by the time spent for the movement of the servo motor. The contact signal turns off when the coil signal is turned off like a timer. The movement completion of an arbitrary servo motor against the driving instruction can be recognized in the form of the contact of an ordinary relay in a sequence process and two timing of the actuation and completion of the servo motor can be handled in the same way as the operations of a timer in the sequence process.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a programmable controller capable of controlling a servo motor, and more particularly to a PC-NC device having a function of detecting completion of movement of a servo motor in sequence processing.

BACKGROUND OF THE INVENTION In recent years, programmable controllers have expanded the range of objects they control, and have come to be able to control not only conventional relays, counters, timers, and registers, but also servo motors. Programmable controllers are intended for sequence processing, and in particular, in relay symbol type programmable controllers, various processes are generally processed by relaying. Therefore, in order to know the operating status of the servo motor, signals such as in-operation, abnormal operation, overrun limit, etc. are assigned a dedicated relay number as a special relay, and the contact signal can be used in a sequence program. These signals are unique to each axis of the servo motor. Of these signals, the operating signal is most often used to detect the completion of an operation.

Conventionally, this signal during operation was processed as follows. First, make sure that the motor is not in operation when you want to drive it. In terms of sequence processing, the conditions for starting the motor and the negative signal during motor operation are ANDed. When this condition is met, a drive command to the servo motor is processed. When the servo motor starts moving, the in-motion signal turns on, or it does not necessarily turn on immediately after starting, so the sequence process waits for the in-motion signal to turn on next. Thereafter, the servo motor remains on until the operation is completed and turns off when the operation is completed, so wait until the operating signal turns off, and when it turns off, the operation is completed.

Problems to be Solved by the Invention However, the above-mentioned operations are operations in a normal case, and in reality, processing is required assuming an abnormal case. For example, the in-operation signal does not always turn on after the servo motor is started, and in the case of a movement amount of O, the in-operation signal remains off. In this case, if there is a process of waiting for the operating signal to turn on, it will lock at that point. In order to avoid this, it is necessary to use a timer or the like to automatically move to the next sequence after a certain period of time has elapsed. Furthermore, if an abnormality occurs during operation, such as when a servo alarm or overrun limit is turned on, the operation signal is usually turned off.

In this case, it is necessary to distinguish from the normal case where the timing of OFF during operation does not indicate the completion of movement.

In actual sequence processing, it is necessary to perform the above-mentioned processing for each axis at each activation timing, which has the drawback of complicating the sequence.

The present invention has been made in view of the above problems, and provides a control device having a function of detecting the completion of movement of a servo motor, which is easy to use in sequence processing.

Means for Solving the Problems In order to solve the above problems, the present invention provides a dedicated relay for detecting the completion of servo motor movement, places this loop immediately before the servo motor drive command, and controls the coil signal of this relay. The completion of the movement is detected by starting the servo motor at the rising edge and turning on the contact signal of the relay at the point in time when the operation according to the movement command of the servo motor is completed.

The present invention uses the method described above to enable servo motor startup and completion processing using the signals of the coil and contact of a general relay in sequence processing, and creates a servo motor programming environment that is highly consistent with conventional sequence processing. realizable.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the main configuration in an embodiment of the present invention. In FIG. 1, 1 is a console for inputting data, 2 is a CPU circuit for editing processing,
3 is a user program memory, 4 is a position data memory for storing the position and speed of the servo motor, 5 is a CPU circuit for execution processing, 6 is a position data memory converted into pulses to be referenced during execution, 7 8 is a data memory for the relay, 8 is a driver circuit for driving the servo motor to a designated position, 9 is an external input/output circuit used for sequence processing, 10 is an editing CPU circuit 2 and an execution CPU circuit 5 It is a shared memory that connects the

Next, the operation will be explained using FIG. 1, FIG. 2, and FIG. 3.

FIG. 2 shows the operating characteristics of a dedicated relay (hereinafter referred to as F relay) for detecting the completion of movement of the servo motor. The F relay operates as a timer, and the timer is shown in Figure 2 (
As shown in b), time counting starts at the rise of the coil signal, and the contact signal is turned on after the set time has elapsed. When the coil signal is turned off, the contact signal is also turned off. In other words, the timer operates so that the contact signal is delayed by a set time with respect to the coil signal. The FIJ Ray is made to basically operate in the same way as this timer, using the transfer time of the servo motor instead of the set time. As shown in FIG. 2(a), a servo motor drive command 12 is programmed immediately after the F relay coil signal 11. Just as the set time starts when the timer's coil signal rises, a servo motor drive command is given to the driver circuit 8 at the rise of the F relay's coil signal to start the movement of the servo motor. Next, just as the contact signal was turned on at the completion of the set time, the contact signal of the F relay is turned on at the completion of movement of the servo motor. By doing this, the F relay operates with the contact signal delayed by the travel time of the servo motor with respect to the coil signal. This contact signal is similar to a timer, and when the coil signal is turned off, the contact signal is also turned off. The above is the basic operation of the F relay.

Next, a processing outline of the above basic operation will be explained based on FIG. 3.

FIG. 3(a) is a flowchart showing an outline of the process.

Figure 3 (b) is the data memory for the F relay, which is the FO
There are 256 points from F255 to F255. Figure 3 (C) is F
It is a detailed structural diagram of one piece of relay data. Bit ○
is contact signal data, bit 1 is current coil signal data, and bit 2 is coil signal data at the previous point in time. FIG. 3(d) is a data structure diagram of a command given to the servo motor.

Now, the program processing for the operation of the F relay shown in FIG. 2(a) will be described according to the flowchart.

First, in step 21, the F relay number corresponding to the F relay number is
Find the data address of data memory.

In step 22, the current coil signal data in the F relay data is copied to the previous coil signal data. In other words, the contents of bit 1 are copied to hit 2. In step 23, the state of the coil signal of the F relay is stored in bit 1 of the F relay data. Step 24 F
Determine the rise of the relay coil signal. The rise of the coil signal is determined using bits 1 and 2 of the F relay data. Rising means that the signal state changes from O to 1, so the previous coil signal state of the F relay data, that is, bit 2 is O, and the current coil signal state, that is, when bit 1 is 1, is that state. Become. When it rises, it advances to the next step, and when it does not, it advances to step 28. In steps 25 and 26, the F relay number, the operation command of the servo motor drive command, and the position data number are stored in the command area of the designated axis. There are as many command areas with the same content as there are axes. In step 27, the status of the command area is set to ready. This will enable the set command. Step 2
In step 8, it is checked whether the status of the command area is ready. If it is ready, continue (2 steps are executed; if not, proceed to step 31. In step 29, the set command is given to the servo motor driver circuit 8. At this time, the position data corresponding to the position data number in the command area is pulsed. In step 3o, the command status is set to run.In step 31, it is checked whether the command status is run, and if it is run, the following processing is performed.In step 32, the servo motor Check whether the movement of 8 has been completed. If the movement is complete, execute steps 33 and 34. In step 33, set the output signal data, that is, bit O, of the F relay data corresponding to the F relay number set in the command area to 1. Step In 34, the command status is set to 5top.

As described above, according to this embodiment, the completion of movement in response to a drive command of an arbitrary servo motor can be known in the form of a general relay contact in sequence processing, and the two timings of starting and completing the servo motor can be known. PC or N
This is a very convenient method for controlling C. Finally, FIG. 4 shows an example of a program when the present invention is applied to palletizing processing. 41 is a completion detection relay FO of the servo motor movement command 42 to the X axis. 43 is a completion detection relay F1 of the servo motor movement command 44 to the Y axis. In this program, when input relay IO of 40 is turned on, commands 42 and 44 to the servo motor are executed, and
When the shaft moves, it can be known from the contact signal of the relay FO, F1 that the shaft moves and the pallet's fortune changes. If the contact signals of the F relay are AND-connected as shown at 45 and 46 in FIG. 4, it is possible to know that the movement of both axes has been completed. If you do the same thing below, you can easily create a program that starts the fire operation after completing one operation.

As described above, according to this embodiment, it is possible to control a servo motor with the same feeling that is accustomed to conventional sequence processing such as solenoids and chucks, and it is a method that is very easy to use for users who have been using PCs.

Effects of the Invention As described above, the present invention detects the completion of movement by arranging a relay dedicated to detecting completion immediately before a drive command is issued to the servo motor, and detecting the completion of movement of the servo motor based on the contact signal of the relay. The timing can be obtained in the form of relay contacts, making the sequence very simple.

In addition, it is an excellent PC that has the unidirectional characteristic of being turned off before movement and turned on only when the movement is completed, making it extremely easy to start and complete programs when operating continuously. - It is possible to realize an NC device.

[Brief explanation of the drawing]

Fig. 1 is a main configuration diagram of an embodiment of the present invention, Fig. 2 is an operational characteristic diagram of the termination detection relay (F relay), and Fig. 3 (
a) is a flowchart showing the control procedure of the microcomputer;
Figures (b), (c), and (d) are data structure diagrams thereof, and Figure 4 is an example of a program when the present invention is applied to palletizing processing. 1...Console, 2...Editing CP
U circuit, 3...User program memory, 4.
...Servo motor position data memory, 5...
... CPU circuit for execution, 6 ... Pulse position data memory, 7 ... Data memory for relay, 8.
...Servo motor driver circuit, 9...
External input/output circuit, 10...Shared memory. Name of agent: Patent attorney Haruaki Ogata et al. Figure 28 (a (b)) Figure Rata Q Reram 441J

Claims (1)

[Claims] A programmable motor capable of driving a servo motor, which has means for processing a relay symbol type program, means for directly driving a servo motor according to a dedicated command in the program, and a servo motor circuit that moves by a predetermined amount according to the command. In a controller, a so-called PC-NC device, a relay coil that processes the command prior to the command, means for giving the servo motor drive command to the servo motor circuit by a rising signal of the relay coil, and when the movement of the servo motor is completed. and a means for turning on the output signal of the relay coil, thereby detecting the completion of the operation of the servo motor.
C device.