JPS63196910A - Controller for floating type carriage - Google Patents

Abstract

PURPOSE:To stably stop a carriage in a target position by decelerating the carriage in the speed control mode and switching the mode to the positioning control mode thereafter to control the stop at the time of stopping the carriage in the target position. CONSTITUTION:In the speed control mode, a switch 8 is opened and a switch 9 is closed. A speed V of the carriage is detected by a speed detector 4, and the output is not only inputted to a compensator 7 for speed control but also negatively fed back to a speed controller 3. The output of the compensator 7 is positively fed back to the controller 3 through the switch 9, and the output of the controller 3 excites a linear induction motor 1 with the opposite phase through a motor driving device 2 to decelerate the carriage. When the speed reaches a prescribed deceleration point V1, the switch 8 is opened and the switch 9 is closed to switch the mode to the positioning control mode, and the phase of the excitation input to the motor 1 is switched to the normal phase. At this time, a position S of the carriage is detected by a position detector 5, and the difference between this position and the stop target position is inputted to the controller 3 through a compensator 6 for position control and the negative feedback output of the detector 4 stops the motor 1 in the target position.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention provides a control device for a floating carrier that mainly stops a floating carrier that transports small items in a predetermined position in a non-contact manner. It is related to.

(Conventional technology) In recent years, as part of office automation (OA) and factory automation (FA), transportation devices have been used to transport slips, documents, cash, fees, workpieces, parts, etc. between multiple points within a building. It is widely used to move.

Since such transport devices are required to transport objects quickly and quietly, a system in which the transport vehicle is supported on guide rails in a non-contact manner is often adopted.

To support a conveyance vehicle without contact, it is common to levitate it using air or magnetism, and among these methods, the method of supporting the conveyance vehicle magnetically has excellent followability to guide rails and noise reduction effect. Therefore, it is the most promising support method.

Conventionally, in order to run such a magnetically levitated carrier,
Its structure is such that the secondary conductor plate of the single-sided linear induction motor is attached to the transport vehicle, and the primary stator of the motor is installed on the guide rail side, thereby providing the transport vehicle with the necessary force for acceleration and deceleration. It is the most widely used because of its simplicity.

In this case, if the stator of the single-sided linear induction motor is installed continuously on the guide rail side, the cost will be high, and the rail itself will be heavy, so the stator should be placed on the rail.
It is often provided only at one location.

When stopping the transport vehicle on the stator placed at a predetermined position on the guide rail, the stator is energized in reverse phase,
The reverse thrust generated by this stops the transport vehicle.

However, with this method, it is difficult to control the vehicle to stop at the target position by giving acceleration/deceleration commands from the Lully control device, and there is also the problem that if the command value is given in steps, the guided vehicle will stop suddenly if the approach speed is low. There is.

(Problems to be Solved by the Invention) The present invention has been made in consideration of the above-mentioned problems. It is an object of the present invention to provide a control device for a floating conveyance vehicle that performs reverse phase excitation to smoothly decelerate the conveyance vehicle and stop it at a target position, regardless of the speed at which the vehicle enters the stator.

(Structure of the Invention) (Means and Effects for Solving the Problems) The present invention detects the speed at which a floating conveyance vehicle approaches the stator of a linear induction motor, and applies a reverse voltage to the stator according to the speed of approach. Levitated transport is divided into two modes: speed control, which controls the phase excitation input and stably decelerates the transport vehicle to a predetermined speed, and positioning control, which moves the transport vehicle to the target position after reaching the predetermined speed. This is a control device for a floating transport vehicle that stops the vehicle at a target position.

(Example) An embodiment of the present invention is shown in FIG.

In FIG. 1, switch 8 is open and switch 9 is closed during speed control mode.

The current position S of the guided vehicle is detected by the position detector 5, and the difference 5rs from the target stop position 3r is input to the position control compensator 6. However, in the speed control mode, the switch 8 is open, so the position The output of the control compensator 6 is not input to the speed controller 3.

The speed ■ of the transport vehicle is detected by a speed detector 4, and its output is input to a speed control compensator 7 and is also negatively fed back to the speed controller 3.

Further, the output of the speed control compensator 7 is positively fed back to the speed controller 3 through the switch 9, and the output of the speed controller 3 is passed through the motor drive device 2 to the linear induction motor If! 11 is subjected to reverse phase excitation, thereby decelerating the transport vehicle.

In this case, the output ■r of the speed control compensator 7 changes in accordance with the speed ■ of the transport vehicle, as shown by the solid line in FIG. 2, and its value becomes greater than the speed V of the transport vehicle.

In other words, the dotted line part in FIG.
means that they have the same value.

Positive feedback of the output vr of the speed control compensator 7 and negative feedback of the conveyance vehicle speed V means that the conveyance speed V as shown in FIG.
The difference Vd between the solid line part and the dotted line part is applied to the speed controller 3.

When a speed control system with a variable gain is configured using the speed control compensator 7 having such characteristics, the conveyance vehicle is decelerated by reverse phase excitation to the linear induction motor 1, and when it reaches a predetermined deceleration point, the conveyance vehicle decelerates. At speeds below, there is no negative phase excitation, and therefore the speed control system will no longer become unstable.

This ensures stable deceleration at the same rate regardless of the approach speed of the transport vehicle.

When the speed of the transport vehicle reaches the predetermined deceleration point (1), switch 9 opens and switch 8 closes, switching from speed control mode to positioning control mode, and at the same time, the excitation input to linear induction 21171 machine 1 is also reversed in phase. Switched from excitation to positive phase excitation.

In this case, the position aS of the guided vehicle is detected by the position detector 6, and the difference from the target stop position 3r is input to the position control compensator 6, whose output is the speed i! It is input to II3 controller 3.

Since the switch 9 is open in the positioning control mode, the output of the switch 7 is not input to the speed lurifier wJ unit 3 in the speed control mode.

The speed ■ of the conveyance vehicle is detected by the speed detector 4, and its output is fed back to the speed controller 3 P4, and the motor drive unit f! ! ! 2
The linear induction motor 1 is stopped at the target position via.

FIG. 4 shows the above control procedure as a flowchart.

Although the above-mentioned embodiment deals with a conveyance vehicle that levitates using a magnetic support method, the same applies to a conveyance vehicle that levitates with air, other gas, or liquid.

Further, a TRfjJ machine driving device, an AC zero cross switch, other switches, or a frequency converter (inverter) can be used.

Furthermore, although the above embodiment shows a case in which a linear induction motor is used to drive the floating vehicle, other electric motors may be used to provide thrust or reverse thrust without contacting the floating object. In general, the present invention is also applicable to cases where, in addition to the push-up type conveyance vehicle, other similar conveyance equipment such as a wheel-running linear motor car is used.

〔Effect of the invention〕

As explained above, according to the present invention, a guide rail laid along a conveyance route, a conveyance vehicle running along this guide rail, and a secondary conductor mounted on this conveyance vehicle are opposed to each other with a gap between them. In a transport device equipped with a stator of a linear induction motor that is disposed along a rail and generates a thrust for moving the transport vehicle between the secondary conductor and the above-mentioned secondary conductor, when controlling the stop of the transport vehicle, it is necessary to It is possible to smoothly decelerate at a constant rate regardless of the approach speed to the stator, and the output circuit of the position control compensator and speed control compensator can be input to the speed controller in the same control system. The speed control mode can be switched to the positioning control mode by simply switching the mode, thereby making it possible to easily perform stable stop control and stably stop the conveyance vehicle at the target position.

[Brief explanation of the drawing]

FIG. 1 is a control block diagram showing one embodiment of the present invention, and FIG.
The figure shows an example of the characteristics of the speed control compensator in the speed control mode, and FIG. 3 is a flowchart showing the control procedure of the present invention. 1 Linear induction motor 2 Den gJ Kiku! FJJ device 3 Speed controller 4 Speed detector 5 Position detector 6th place! ! LIJU supplement! i device 7 speed control compensator 8.9 switch (8733) agent patent attorney Yoshiaki Inomata (
(and 1 other person) Figure 1 ζσ 2 1', 1

Claims (1)

[Claims] In a control device for a floating guided vehicle, in which a linear induction motor is configured by a primary stator disposed at a predetermined position on a guide rail and a secondary conductor attached to a floating guided vehicle, and the guided vehicle is driven by the thrust of the linear induction motor. , is equipped with a switching circuit that switches between a speed control mode and a positioning control mode, and when the floating conveyance vehicle is stopped at a target position on the stator, it is decelerated to a predetermined speed in the speed control mode and then switched to the positioning control mode. A control device for a floating carrier, characterized by performing stop control.