JPH03164812A - Linear actuator control device - Google Patents

Abstract

PURPOSE:To reduce an error between the actual position of an actuator and the position data of a position display device by presetting a position detector simultaneously with the stop of a linear actuator. CONSTITUTION:When an origin sensor 3a is set to the non-detecting state and the output is changed from the high level to the low level, an edge detector 6 outputs a pulse signal (d). A controller 7 outputs the control signal, which stops an actuator 1, to a driver 8 by this pulse signal (d), and a position display device 7 is preset to a preliminarily set value. At this time, the actuator 1 is moved at low speed in the position, where a display device is preset, and is stopped just after. Thus, the error between the actual position of the actuator 1 and position data of the display device 5 is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is useful for detecting and displaying the entire position of a linear actuator when presetting the origin of a position detector such as a linear scale or laser null.

The present invention relates to a linear actuator control device that controls the movement of a linear actuator.

BACKGROUND ART In a conventional linear actuator control device, as shown in FIG. 3, when a linear actuator 1 (hereinafter simply referred to as an actuator) driven by a driver 8 and moving on a guide 2 moves in the direction of the origin, five IF points are set. When the sensor 32L detects the detected portion 3b at the origin, the controller 7 stops the actuator 1. When the moving direction of the actuator 1 is reversed and moved inward from the origin, and the preset sensor 11a detects the preset detected part 1 l b'i, the edge detector 6 presets the position indicator 6 to a preset setting value. Outputs the name of the person. The position of the actuator 1 can be obtained by converting the amount of movement of the linear scale 4b that moves together with the actuator 1 by the linear scale detector 4a using the position indicator 6, but the 1 position indicator 6 is preset to the set value. If the set values are correct and the preset position is correct, the position of the actuator 1 and the position data obtained from the position indicator 6 will match.

Problems to be Solved by the Invention However, according to the conventional configuration, the actuator 1 moves at a high speed, and it takes a long time from when the preset sensor 11 & detects the preset detected part 11 bi to when the position indicator 6 is preset. If there is a delay, the error between the actual position of the actuator 1 and the position data of the position indicator 6 will increase.

In addition, in order to reduce this error, actuator 1
When the moving speed of
It takes some time for the actuator 1 to move at low speed to the position where b is detected.

The present invention has been made in view of these points, and reduces the time required to preset the position indicator 6, thereby reducing the error between the actual position of the actuator 1 and the position data of the position indicator 6. The present invention aims to provide a linear actuator control device.

Means for Solving the Problems In order to solve the above-mentioned conventional problems, the present invention includes a sensor for detecting the origin position of a linear actuator, and a sensor for detecting the moving direction of the linear actuator when the output state of the sensor is in the detection state. The linear actuator is configured to be reversed and moved at low speed, and to stop the linear actuator when the sensor output transitions to a non-detected state, and a position detector that is preset at the same time as the linear actuator stops.

According to the above-described configuration, the present invention reverses the moving direction of the linear actuator and moves it at a low speed when the sensor that detects the origin position is in the detection state while the linear actuator is moving, and the sensor is in the non-operational state. When transitioning to the detection state, the linear actuator is stopped and
Preset the position detector at the same time.

Embodiment Hereinafter, a linear actuator control device according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a linear actuator control device in an embodiment of the present invention. In Fig. 1, 1 is the actuator, 2 is the guide, 31L is the origin sensor,
3b is the detected part at the origin, 4a is a linear scale detector,
+b is a linear scale 6 which is a position detector, 6 which is an edge detector, 7 which is a controller, and 8 which is a driver.

The actuator 1, which moves on the guide 2 and is driven by the driver 8, retreats to the origin position, the origin sensor 3a detects the detected part 3bfe at the origin, and the output signal becomes H (see Fig. 2).
C)), the controller 7 reverses the moving direction of the actuator 1 (FIG. 2(b)) and outputs a control signal to the driver 8 so that the actuator 1 moves inward from the origin position at low speed.

When the origin sensor 3a enters the non-detection state and the output changes from H to L, the edge detector 6 outputs a pulse signal (Fig. 2(d)).
) is output. In response to this pulse signal, the controller 7 outputs a control signal to the driver 8 to stop the actuator 1, and the 1 position indicator 7 is reset to a preset value.

The linear scale 4b moves together with the actuator 1. The linear scale detector 4a detects the amount of movement of the linear scale 4b and outputs it to the position indicator 6. The position indicator 6 converts this movement amount into position data.

The display 6 displays position data of the actuator 1 based on preset setting values.

Therefore, an error occurs between the actual position of the actuator 1 and the position data on the display 6 if the set value is incorrect or if the position of the actuator at the time of presetting is incorrect.

However, in this embodiment, the actuator 1 moves at a low speed at the position where the 1 indicator 6 is preset and then stops immediately, so that the error is small. Further, the distance that the actuator 1 moves at low speed is short and is less than the range in which the origin sensor 3a detects the detected portion 3b.

Note that the range in which the origin sensor 3a can detect the detected part 3b is as wide as several n, so the actuator 1 passes one line past the detected part 3b before the origin sensor 3a detects the detected part 3b and stops. It will not stop where it cannot be detected. Actuator 1. Unless there is a case where the actuator 1 runs out of control due to an abnormality in either the controller 7 or the driver 8, the actuator 1 will stop within the range where the origin sensor 3a detects the detected portion 3b. Therefore, the origin sensor 3a is inside the detected part 3b.

It is usually impossible to detect both outer edges.

Effects of the Invention As described above, according to the present invention, the time required to preset a position detector (position indicator) can be shortened. Also, since the number of sensors can be reduced by one, the position adjustment is reduced by one, which also reduces costs.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an embodiment of a linear actuator control device according to an embodiment of the present invention, Fig. 2 is a main waveform diagram of the linear actuator control device of the present invention, and Fig. 3 is a conventional example of a linear actuator control device. FIG.

Claims (1)

[Claims] A sensor for detecting the origin position of a linear actuator, and when the output state of the sensor becomes a detection state due to the movement of the linear actuator, the moving direction of the linear actuator can be reversed and the linear actuator can be moved at a low speed. a control means that stops the linear actuator when the sensor transitions to a non-detection state; and a position detector that detects a relative position with respect to the origin position due to movement of the linear actuator at the same time as the linear actuator stops. A linear actuator control device that is characterized by being able to preset to any value.