JPS6248843B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention is utilized in a control command circuit that is controlled by a microprocessor system and controls the rotation of a servo motor.

[Conventional technology]

FIG. 1 is a block diagram showing an example of a general control circuit. That is, it is a control system composed of a microprocessor system 1, a control command circuit section 2, and a servo motor control section 3, and controls the voltage and pulse width applied to the servo motor 4 to rotate the servo motor 4. The output of the sensor 5, which outputs an output corresponding to the rotation of the servo motor 4, is input to the servo motor control section 3, and is converted into a response signal 10 having a number of pulses proportional to the amount of rotation, for example. The microprocessor system 1 first sends the amount of rotation of the servo motor to the stop position to the control command circuit section 2 via the data bus 8, and sends a control signal to the control bus 7 to set the amount of rotation. It is configured as follows.

The conventional control command circuit section 2 is configured as shown in FIG. 2, for example. That is, the amount of rotation of the servo motor 4 given via the data bus 8 is set in the subtraction counter 51 according to instructions from the control bus 7 . The contents of the subtraction counter 51 are decremented by the response signal 10 from the servo motor control section 3 (FIG. 1). Therefore, the counter output signal 54 indicates the remaining number of revolutions of the servo motor. The decoding circuitry 52 converts the numerical value of the counter output signal 54 into an address signal 55 for the read-only memory 53 and outputs it.

At each address of the read-only memory 53, command information such as the rotational speed for the servo motor 4 is stored in advance. Therefore, by appropriately setting the contents of the decoding circuit network 52 and the read-only memory 53, it is possible to output a command signal 9 corresponding to the contents of the subtraction counter 51, as shown in FIG. 3, for example. Further, when the numerical value of the counter output signal 54 becomes "0", the decoding circuit network 52
outputs an interrupt signal 6 and sends it to the microprocessor system 1 (Fig. 1), which sends the rotation amount of the servo motor for the next step to the data bus and performs the same process as described above. Control the servo motor by repeating the operation.

The servo motor control section 3 has a control function of controlling the pulse width, voltage, etc. to be applied to the servo motor 4 using the command signal 9, and applying the same to the servo motor 4 to drive the servo motor 4.

[Problem that the invention seeks to solve]

In the conventional configuration described above, by using a programmable read-only memory (PROM) as the read-only memory 53, it is possible to cope with small changes in the constants of the servo system. However, a relatively large change in the constants of the servo system requires circuit changes in the decoding circuit network 52 and changes in the read-only memory 53. These changes are a big problem for circuits implemented on printed circuit boards. Further, there is a drawback that the configuration scale of the read-only memory 53 and the decoding circuit network 52 increases in accordance with the number of command signals, and the number of parts constituting the circuit increases. Furthermore, it is difficult to use general-purpose LSIs or the like for these circuits.

The present invention solves the above-mentioned conventional drawbacks and provides a general-purpose
The purpose of this invention is to provide a servo system control command circuit that is a small-scale circuit using LSI, IC, etc., and can flexibly deal with changes in servo system constants.

[Means for solving problems]

The present invention provides a microprocessor system that is connected between a microprocessor system that controls the rotation of a servo motor, and a servo motor control section that is connected to the servo motor and that applies rotational current to the servo motor and takes in the output of a rotation sensor of the servo motor. means for inputting the amount of rotation of the servo motor as a digital signal from the microprocessor system; means for outputting this digital signal to the servo motor control section; and means for setting the amount of rotation and subtracting it with a signal corresponding to the output of the rotation sensor. In a control command circuit for a servo system, the control command circuit includes a counter means for counting and supplying an interrupt signal to the microprocessor system when a predetermined value is reached. The counter includes a command buffer register for accumulating the amount of rotation; The means includes, in addition to a first counter that sets the current amount of rotation and performs subtraction counting, a second counter that sets and waits for the next amount of rotation input from the microprocessor system;
The present invention is characterized in that it includes means for switching between these two counters in synchronization with the generation of the interrupt signal.

[Effect]

The control command circuit of the present invention sets the rotation amount of the servo motor that the microprocessor system outputs to the data bus in a counter, and decrements the rotation amount based on the response signal from the servo motor, and when the count value becomes 0. Outputs an interrupt signal. Two counters are provided for this countdown, and these are used by switching. That is, each time the content of the first or second counter becomes 0, it alternately enables the other counter to be subtracted, and also sends an interrupt signal to the microprocessor system and a gate signal to the output register. Then, the input signal at that time is outputted as a command signal, and the microprocessor system causes the first or second counter to set the rotation amount of the next step in response to the interrupt signal. After the output register latches the current input signal by turning off the interrupt signal, the command signal for the next step is set in the command buffer register.

〔Example〕

Next, the present invention will be explained in detail with reference to the drawings.

The overall configuration of the present invention is the same as that shown in FIG. 1 described above.

FIG. 4 is a circuit diagram showing the main parts of one embodiment of the present invention, and is a circuit diagram showing the control command circuit section 2 shown in FIG.
Only the corresponding parts are shown. The present invention is characterized by this part.

The microprocessor system 1 outputs command signals as well as the amount of rotation of the servo motor 4. These are sent via the data bus 8, and the control signals from the control bus 7 are used to control the counters, registers, etc. described below. is set to

The interval timer 19 is a first counter 1
9-1 and a second counter 19-2, each counter 19 calculates the amount of rotation of the servo motor to the next stop position given by the data bus 8 according to the control signal given from the control bus 7. −
Set to 1,19-2. The data bus 8 is connected to terminals _D0 to _D7 of the interval timer 19, and the control bus 7 is connected to terminals A0, A1,
,,It is connected to the. The two counters 19-1 and 19-2 receive the response signal 10 at their terminals.
When input to CLK1 and CLK2, the count value is subtracted, and when the count value becomes 0, terminals OUT1 and OUT
This configuration outputs a high level to 2. This subtraction operation is performed when a high level is input to each of the terminals GAT1 and GAT2, and this subtraction operation is prohibited when a low level is input to these terminals.

Terminal OUT of counters 19-1 and 19-2
1 and OUT2 signals are sent to the first OR gate 23
The output of the first OR gate 23 is input to the microprocessor 1 (FIG. 1) as an interrupt signal 6.
sent to. At the same time, the D-type flip-flop 20 is set by the output of the OR gate 23 shown in FIG.

The positive output terminal Q of the flip-flop 20 is connected to the terminal GAT1 of the counter 19-1. The negative output terminal of the D-type flip-flop 20 is connected to its own D terminal and also to the terminal GAT2 of the counter 19-2. Therefore, counter 19-1 or 19-
2, one of them decrements the count, and when the count value reaches 0, the interrupt signal 6 becomes high level, and the state of the D terminal of the D-type flip-flop 20 at that time is outputted to the positive output terminal Q.

As a result, the counter that has been decrementing until now is prohibited from decrementing, and the other counter is allowed to decrement. Furthermore, when the initial setting pulse 31 is given by the control bus 7, the signal that negates the output of the inverter 32 is
By inputting the reset terminal of flip-flop 20, flip-flop 20 is reset. That is, the initial setting pulse 31 enables the second counter 19-2 to decrement the count.

On the other hand, the command signal given via the data bus 8 is
It is set in the command buffer register 22 by a command signal setting pulse 30 given via the control bus 7. The output of the command buffer register 22 is input to the output register 21. Then, the initial setting pulse 31 and the output of the first OR gate 23 are passed through the second OR gate 24,
It is connected to the G terminal as a gate signal of the output register 21. When a high level is input to the terminal G of the output register 21 due to input of the initial setting pulse 31 or count-up of the counters 19-1 and 19-2, the input data of the output register 21 is
D ₀ to D ₈ are directly output to the output terminals Q ₀ to _{Q 7} , and when the gate signal becomes low level, the output register 21 latches the data at that time, and thereafter latches the data until the gate signal becomes high level. Output data.

The output data of the output register 21 is sent as a command signal 9 to the servo motor control section 3 shown in FIG. In addition, the initial setting pulse 31 is applied to the inverter 32.
, and then invert it again and input it to the reset terminal of the flip-flop 20.

Next, the operation of this embodiment will be explained with reference to FIGS. 4, 5, and 6. FIG. 6 is a time chart showing the contents of registers 22, 21, counters 19-1, 19-2, and the state of interrupt signal 6. It is now assumed that the servo motor is stopped by a stop command A. At this time, the contents of the command buffer register 22 and the output register 21 are the stop command A, and the contents of the counters 19-1 and 19-2 are "0". Then, as shown in Fig. 5, command B makes n ₁ rotation, and command C gives n 1 rotation.
n ₂ rotations, n ₃ rotations by command D, ..., n _Z rotations by command Z, total rotation amount shall be rotated. The commands A to Z and the rotation amounts n ₁ to n _Z are programmed or calculated by the microprocessor system and outputted as appropriate for the control system. The signal is then applied to the command buffer register 22 and the interval timer 19 through the data bus 8, and set by the control signal on the control bus 7, respectively.

First, the microprocessor system outputs the initial rotation amount _n1 to the data bus 8, and the second counter 19-2 is output by the control signal from the control bus 7.
Set the rotation amount n ₁ to (see Fig. 6c). Next, the microprocessor system outputs the next rotation amount n ₂ to the data bus 8, and the rotation amount n ₂ is set in the first counter 19-1 by the control signal from the control bus 7 (see FIG. 6d). ). At this time, the output of the first OR gate 23 becomes low level and the output register 21 latches the stop command A. Next, command B is output to the data bus 8,
Command B is set in the command buffer register 22 by the command signal setting pulse 30 (see FIG. 6a). Then, when the initial setting pulse 31 is input next, the output register 21 latches the command B and outputs the command B (see FIG. 6b). Flip-flop 20 is also reset.

The servo motor control section 3 (Fig. 1) is activated by command B.
drives the servo motor, and when the servo motor rotates, a response signal 10 corresponding to the amount of rotation of the servo motor is sent back. The response signal 10 is sent to the counter 19
-1 and 19-2 count terminal CLK1,
Although connected to CLK2, only the second counter 19-2 can now count down. Therefore, the content (n ₁ ) of the second counter 19-2 is decremented by the response pulse 10 (see FIG. 6c). During this time, the servo motor is rotating according to command B. After that, the command C for the next step is given via the data bus 8, and the command setting pulse 3
0 in the command buffer register 22 (FIG. 6a).

On the other hand, due to the rotation of the servo motor, the counter 19
-2 is decremented, and when the rotation amount _n1 is reached, the count value becomes "0" and a high level is output to the terminal OUT2. As a result, the interrupt signal 6 becomes high level (FIG. 6f), and at the same time, the flip-flop 20 is inverted, prohibiting the counter 19-2 from counting down, and allowing the counter 19-1 to count down (FIG. 6). d). In addition, the second OR circuit 24
Since the gate signal is applied to the output register 21 via the output register 21, the output register 21 outputs the command C (FIG. 6b). That is, the servo motor rotates according to the command C, and a response signal 10 corresponding to the amount of rotation is generated.
The counter 19-1 starts counting down.

When the interrupt signal 6 is sent to the microprocessor system, the microprocessor system performs interrupt processing. That is, the rotation amount _n3 is set in the counter 19-2. When the output terminal OUT2 of the counter 19-2 becomes low level due to the setting of the rotation amount _n3 , the interrupt signal 6 and the terminal G of the output register 21
becomes low level (FIG. 6f), and the command C is latched in the output register 21. Thereafter, the microprocessor system outputs the command D to the data bus 8, and causes it to be set in the command buffer register 22 by the control signal of the control bus 7 (FIG. 6a).

When the content of the counter 19-1 becomes "0", the counter 19-2 becomes capable of decrementing in the same manner as described above, and the output register 21 outputs the command D.
After the rotation amount _n4 is set in the counter 19-1, the command E is set in the command buffer 22.

By repeating the above operations, when n _Z rotation is finally completed by command Z, a series of control operations of all steps is completed, and by command A, the entire servo system is brought to a halt state.

〔Effect of the invention〕

In this way, in the circuit of the present invention, all the control information for the servo system is generated by the microprocessor system, so it is possible to deal with changes in the specifications of the servo system by changing the program. be. That is, it is possible to make significant changes to the command contents and other matters without changing the hardware such as replacing the ROM as in the past.

Further, although two counters are provided, the switching corresponding to the next step is automatically performed by the output signal of one of the counters, and it is possible to switch without program intervention. Therefore, the interrupt processing of the microprocessor system is simple, and restrictions on interrupt acceptance time are relaxed.

According to the present invention, even if the constants of the servo system, such as the load inertia of the motor, are significantly different, this can be handled by a program without converting the hardware. Therefore, it is possible to perform highly flexible and good control. Furthermore, the hardware configuration is simple and requires only a small number of parts. For example, even if there are many types of type and the moment of inertia of each type is greatly different, it is possible to change the command signal according to the type, so that the various types can be used in the optimal condition. be able to.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of a general servo system control command circuit in which the present invention is implemented. FIG. 2 is a block diagram showing an example of a conventional control command circuit section. FIG. 3 is a diagram showing an example of the relationship between the contents of a conventional subtraction counter and a command signal. FIG. 4 is a block diagram including a partial logic circuit diagram showing one embodiment of the present invention. FIG. 5 is a diagram showing the relationship between the command signal of each step and the rotation speed in the embodiment. FIG. 6 is a time chart showing the contents of each register and counter, the state of an interrupt signal, etc. in the embodiment. DESCRIPTION OF SYMBOLS 1... Microprocessor system, 2... Control command circuit section, 3... Servo motor control section, 4...
... Servo motor, 5 ... Sensor, 6 ... Interrupt signal, 7 ... Control bus, 8 ... Data bus, 9 ... Command signal, 10 ... Response signal, 19 ...
...Interval timer, 19-1...First counter, 19-2...Second counter, 20...D
type flip-flop, 21...output register, 2
2... Command buffer register, 23, 24... OR gate, 30... Command signal setting pulse, 31...
...Initial setting pulse, 32...Inverter.

Claims (1)

[Scope of Claims] 1. Between a microprocessor system 1 that controls the rotation of the servo motor and a servo motor control unit 3 that is connected to the servo motor and applies rotational current to the servo motor and captures the rotation sensor output of the servo motor. means for inputting the amount of rotation of the servo motor as a digital signal from the microprocessor system, means for outputting this digital signal to the servo motor control section, and means for setting the amount of rotation to the output of the rotation sensor. In a control command circuit for a servo system, the control command circuit includes a counter means that performs subtraction counting with a corresponding signal and provides an interrupt signal to the microprocessor system when a predetermined value is reached, wherein the input means comes from the microprocessor system. A command buffer register 22 that accumulates the amount of rotation according to the command signal setting pulse.
The output means includes an output register 21 that receives the output of the command buffer register and outputs the accumulated content upon generation of the interrupt signal, and the counter means sets the current rotation amount. In addition to the first counter 19-1 that performs subtraction counting, a second counter 19-2 is provided that waits after setting the next rotation amount input from the microprocessor system, and generates the interrupt signal. A servo system control command circuit comprising means 20 for switching these two counters in synchronization with the servo system.