JPH02292608A - positioning control device - Google Patents

Abstract

PURPOSE:To attain positioning control which can correspond to various requests by permitting a stop signal to set the value of a setting stop position in a deviation counter, switching a system to positioning control and to stop an object in a target position. CONSTITUTION:The counter 17 counting pulses from an encoder 4 is cleared by the rise of the stop signal LS. A difference between a setting moving amount which is set in a stop position setting switch 14 and the counter 17 is calculated and it is set in the deviation counter in a micro computer 11. When the value of the deviation counter is less than speed setting VR1 (VR2), the value of the deviation counter is D/A converted 16, and is outputted to a servo amplifier 2 as a speed command. When the stop signal LS is given, the system is switched to the positioning control of a deviation counter system, and the object moves by the setting moving amount and is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a positioning control device in a servo system.

[Conventional technology]

In conventional servo positioning control devices, positional information such as a starting point and an ending point is generally programmed in advance, and positioning is performed based on this information.

[Problem to be solved by the invention]

However, the above-mentioned devices cannot respond to a request to receive a signal from the outside, then move by a certain amount and then stop, and therefore have a problem in that the range of application is limited.

[Means to solve the problem]

Until it receives a stop signal, it is controlled as a speed servo that rotates at the speed set by the speed setting device, and when the stop signal is received, it switches to positioning control using the deviation counter evening method, and the speed set by the stop position setting device is changed. It moves by the number of pulses that were set and enters the servo solenoid state.

[Effect]

By setting the value of the set stop position in the deviation counter by the stop signal, and thereafter switching to positioning control using the deviation counter 2 and stopping at the target position, positioning control that can meet various demands is made possible.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of the invention. In the figure, ■ is a positioning control device, which includes a processing device (microcomputer) 11 such as a microcomputer, and volumes 12 (VR1) and 13 (VR2) for speed setting before stopping.
, a stop position setting switch 14 for setting the amount of movement P until stopping, a memory 15, a D/A itn device 16, a counter 17 for counting pulses from the encoder 4, and the like. Note that 2 is a nervous amplifier and 3 is a motor. Further, although two speed setting polyurethanes are provided here, this number is determined as necessary.

FIG. 2 is a flowchart for explaining the operation of FIG. 1, and FIG. 3 is a time chart for explaining the operation.
FIG. 4 is a block diagram for explaining the main part of this invention. The operation will be explained below with reference to these figures.

That is, steps (1) to (2) in FIG. 2 show the speed selection process, in which either one of the speed setting polygons VR1 and VR2 is selected, and this is directly output to the servo amplifier 2 as a speed command. SBUS of Stesop ■ in Figure 2
Y indicates a flag that is set to "0" upon completion of speed control.

This situation is shown in time charts as shown in Figure 3 (a) and (
mouth). In other words, turn on the speed selection signal VSELI (or VSEL2) as shown in the figure (mouth),
This is a process for setting the speed of the motor to the speed determined by the speed setting volume VRI (or VR2) as shown in FIG.

On the other hand, Stenop ■~0 indicates the positioning control operation of the deviation counter evening type, which is performed after stop No. 13 LS is turned on. First, at the rise of stop signals ■ and S, the flag SBLISY is set to '' (see ■), and the counter 1 that counts the pulses from the encoder 4.
7 (Figure 2. Shown as FBCT in Figure 4)
Clear (see ■). Note that the positioning control method using a deviation counter itself is well known.

Next, the difference between the set movement IP set in the stop position setting switch 14 and the counter FBCT is calculated, and this is set in the deviation counter ERCT (see [Phase]).

Then, the value of this deviation counter ERCT is the speed setting VR
If it is less than I (or VR2), the deviation counter ERC
The value of T is converted from digital to analog by the D/A converter 16 and output as a speed command to the servo amplifier (■, @
reference). On the other hand, if the value of the deviation counter ERCT is equal to or higher than the speed setting VRI (or VR2), the speed setting V
Output the speed of RI (or VR2) as is <0.
(see 0). This is to prevent the speed command from jumping up. In addition, in reality, as shown in FIG. 4, the limiter 18
is provided to prevent the deviation from becoming too large, while switching is made so that the speed command VRI (or VR2) is given as is.

In this way, when the stop signal LS is given, the positioning control is switched to the deviation counter method, and the set movement IP
The vehicle will be forced to move and stop. Stop signal LS
An example of O is shown in FIG. 3 (c).

Further, FIG. 3(a) shows the movement of the motor, where the solid line section shows the case where the deviation is large, and the dotted line section shows the case where the deviation is small.

By doing the above, it becomes possible to do the following things that were not possible in the past.

FIG. 5 is a block diagram showing an example of application of the present invention.

That is, marks 6 are attached in advance to the workpieces 5 arranged at irregular intervals, and when the marks 6 are detected by the optical sensor 7, the workpieces 5 can be moved by a certain amount and stopped. It becomes possible to expand the scope of application. FIG. 6 is a time chart for explaining the operation, which is the same as FIG. 3 except that a mark detection signal is introduced as a stop signal, so the explanation will be omitted.

〔Effect of the invention〕

According to this invention, it is possible to switch between speed control and positioning control using an external signal, so it is not only possible to easily position workpieces lined up at uneven intervals, but also to make it possible to enter a servo lock state when stopped. This provides the advantage of flexible control.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a flow chart for explaining the operation of FIG. 1, FIG. 3 is a time chart for explaining the operation, and FIG. 4 is a flow chart for explaining the operation of FIG. FIG. 5 is a block diagram showing the main part of the invention, FIG. 5 is a block diagram for explaining an application example of the invention, and FIG. 6 is a time chart for explaining its operation. Code explanation 1...Positioning control device, 2...Servo amplifier, 3
... Servo motor, 4 encoders, 5... Workpiece,
6... Mark, 7... Optical sensor, 11... Data processing device (microcomputer), 12.13... Speed setting volume, 14... Stop position setting switch, 15...
-Memory, 16...D/A converter, 17...Counter. S 2 z 3113 figure

Claims (1)

[Claims] 1) at least one speed setting device and a stop position setting device; usually when a servo motor is driven at a speed set by the speed setting device and a stop signal is received from the outside; A positioning control device comprising: a control device that switches to a deviation counter type positioning control, moves by the amount of movement set by the stop position setter, and puts the servo in a locked state.