JPS6387103A - Carrier system - Google Patents

Abstract

PURPOSE:To enable a carrier unit to be stopped smoothly in a non-contact state, by controlling a thrust based on a speed when the speed of the carrier unit is of a specified value or more and based on the speed and a deviation from a desired stop position when the speed is of a value less than the specified value. CONSTITUTION:A speed detector 19 is connected to a driving source 9 via an amplifier 27, and a positional deviation detector 21 is connected to the driving source 9 via a switch 29 and the amplifier 27. By a speed comparator 33, the speed signal of the speed detector 19 is compressed with a previously-set specified value, and when a speed is of the specified value or more, then the switch 29 is turned OFF, and when the speed is of a value less than the specified value, then the switch 29 is turned ON. As a result, when the speed of a carrier unit 1 is of the specified value or more, then the input of the speed signal only to the driving source 9 is provided, and when the speed of the carrier unit 1 is of the value less than the specified value, then the input of a positional deviation signal added to the speed signal is also provided.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a conveyance device driven by, for example, a linear induction motor.

(Prior Art) Conventionally, a device for moving a carrier using, for example, a linear induction motor is provided with a station section for stopping or starting the carrier on a relatively long conveyance path on which the carrier is transported. A linear induction motor is disposed in this station section, and by inducing a sliding current in a secondary conductor connected to the carrier, thrust is applied to the carrier through interaction to accelerate and decelerate the carrier.

(Problems to be Solved by the Invention) In order to stop the conveyance body driven in this manner at a desired position, mechanical braking is not required since the linear induction motor does not have a holding force. However, such mechanical υj movement generates noise and is prone to wear due to a friction of the contact part during -11 rotation, and the braking force and braking timing must be changed depending on the speed of the conveyor and the magnitude of the weight Q. Moreover, if there is an error in the braking force or if the braking is done too early or too late, there is a problem that the stopping position is likely to deviate from the desired position and it is difficult to adjust to the desired stopping position.

The present invention has been made in view of the above problem, and an object of the present invention is to provide a conveying device that can accurately stop a conveying body at a desired position without relying on mechanical contact.

[Configuration of the Invention (Means for Solving Problems) A conveying device according to the present invention includes a conveying body, a conveying path for moving the conveying body, and a conveying path installed at a desired interval. and a stator that applies a thrust to the general conveyance body, a slit provided in the conveyance body, and a slit detection means provided along the conveyance path for detecting the slit, A speed detection means for detecting the speed of the transport body based on the detection data of the slit detection means, and a position deviation detection means for detecting a positional deviation of the transport body from a desired stop position based on the detection data of the slit detection means. If the speed detected by the speed detecting means is higher than a predetermined value, the speed detected by the speed detecting means is based on the detection by the speed detecting means, and if it is less than the predetermined value, the position deviation detecting means is detected in addition to the detection by the speed detecting means. a drive source that applies a thrust force to the conveying body through the stator based on the above; a weight 1 detection means that detects suspension of the conveyance body; and an amplification means for amplification.

(Function) In the above configuration, when the transport body B advances along the transport path by the thrust of the stator and approaches the stator, the slit detection means detects the slit, the speed detection means detects the speed, and the position deviation detection means detects the position deviation. To detect. Next, when the speed of the carrier is equal to or higher than a predetermined value, the speed detecting means and lf
Based on the detection by the f1 detection means, the drive source controls the thrust of the stator, and the conveyor is smoothly decelerated in a non-contact state. When the speed of the transport body becomes less than a predetermined value, the drive source controls the thrust based on the detections of the speed detection means, the mold opening detection means, and the position deviation detection means, and the drive source controls the thrust from the desired stop position of the transport body. The deviation is corrected to accurately stop the conveyor at the desired position.

(Example) Examples of the present invention will be described in detail below based on the drawings.

1 to 3 show a conveying device according to an embodiment of the present invention. Here, FIG. 1 is a schematic overall configuration diagram of this apparatus, FIG. 2 is an enlarged view of the slit and slit detection means, and FIG. 3 is a time chime 11-1-.

In FIG. 1, a conveyor 1 is movable along a conveyor rail 3 serving as a conveyance path, and a secondary conductor 5 is attached to the conveyor 1.
are connected. A stator 7 of a linear induction motor is provided at the stop junction of the w1 feed rail 3, and the stator 7 induces a sliding current in the secondary conductor 5, thereby imparting thrust to the carrier 1 through interaction. do. A drive source 9 is connected to the stator 7, and the drive source 9 changes frequency and voltage! The structure is such that the thrust of the two sending bodies 1 is controlled U++.

Note that this drive source 9 may be an inverter that makes the frequency and voltage variable, or may have a configuration that makes only the voltage variable.

As shown in FIG. 2, a slit plate having a plurality of slits 11 with a regular pitch is fixed to the conveyor 1. As shown in FIG.

On the other hand, on the L side near the stator 5, there is a transport rail 3.
Two slit sensors 13 and 15 are installed as slit detection means at positions along. Slit sensor 13
．． 15 is capable of reading the slit 11, and both are arranged at intervals different from an integral multiple of the pitch of the slit 11.

The slit sensors 13 and 15 are connected to a clock circuit 17. The clock circuit 17 is connected to the slit sensor 13,1
5 calculates the pulse and direction from each output signal as the detection data of the slit 11 read. That is, for example, when the traveling direction of the carrier 1 is the direction of the arrow in FIG. 1 and the slit sensor 13.15 detects the slit 11 as shown in FIG. 3, the rising edge of the output signals of both sensors 13.15 The pulse is detected at the falling edge, and the direction is detected from the phase shift of the output signal.

The clock circuit 17 includes a speed detector 19 as a speed detection means and a position deviation detector 2 as a position deviation detection means.
1 are connected in parallel. Position deviation detector 2
The initial value setting means 23 is connected to the passing sensor 2 provided on the conveyor rail 3.
5 trigger signals are input. The passage sensor 25 is provided in front of the stator 7 with respect to the traveling direction of the carrier 1, and outputs a trigger signal when the carrier 1 passes, whereby the initial value preset in the initial fill setting means 23 becomes the position deviation. is applied to the detector 21.

The speed detector 19 converts the period of pulses into a signal of the speed of the carrier 1 taking the direction into consideration, and the position deviation detector 21 calculates the number of pulses from the given initial value taking the direction into consideration and converts it to the desired value. It is converted into a deviation signal of the distance of the carrier 1 from the stop position.

The speed detector 19 is directly connected to the drive source 9 via an amplifier 27 serving as an amplifying means, and the position deviation detector 321 is connected to the drive source 9 via an openable/closeable switch 29 and the amplifier 27 in series. Therefore, the speed signal is always input to the drive source 9, but the position error signal is input to the 0N of the switch 29.
-OF and F control its input.

A 1 m detection means 31 is connected to the amplifier 27. The weight detection means 31! ! ! It is installed near the starting station on the transport rail 3, detects the weight of the carrier 1, and transmits the amplifier 2.
A weight signal is output to 7. On the other hand, the amplifier 27 has a variable gain based on the weight signal from the weight detection means 31, and converts the speed signal or the positional deviation f into a signal proportional to the weight.

The switch 29 connects the speed detector 19 via the speed comparator 33.
It is connected to the. The speed comparator 33 compares the absolute value of the speed signal from the speed detector 19 with a preset predetermined value, and turns off the two switches when the speed is above the predetermined value, and turns off the two switches when the speed is less than the predetermined value. Turn both on. As a result, when the speed of the conveyor 1 is equal to or higher than the predetermined value, the drive source 9
Only the amplified speed signal is inputted, and when the speed of the carrier 1 is less than a predetermined value, the position error signal multiplied by Ij is also inputted to the amplifier 27 in addition to the amplified speed signal.

Next, the action will be explained.

In the above configuration, the carrier 1 moves along the carrier rail 3 by inertia due to the thrust given in advance by the starting station, and when it passes over the passage sensor 25, the initial value setting means 23 sends the desired position l deviation detector 21. An initial II value is set for detecting the positional deviation from the stop position. Thereafter, when the carrier 1 approaches the stator 7 of the stop station, the slit sensor 13.15 reads the slit 11 of the carrier 1. The signals from the slit sensors 13 and 15 are input to the clock circuit 17 and become pulses and directions. Each deviation is detected.

The speed of the speed detector 19 is always inputted to the drive source 9, and therefore, the drive source 9 rapidly supplies a current to the carrier 1 in order to provide the carrier 1 with a thrust that is inversely proportional to the velocity and weight R of the carrier 1. As a result, a braking force proportional to the speed J3 and the weight of the carrier 1 is applied to the carrier 1, and the carrier 1 is decelerated. Such speed control contributes to stabilizing the position differences i and IIm, which will be described later, and also suppresses rapid movement of the carrier 1 immediately after the two switches are turned on.

When the speed of the carrier 1 becomes less than a predetermined value, the switch 27 is turned OFF.
N, and the drive 19 is driven by the speed and weight ff of the carrier 1.
l Hill IE is increased in the direction of correcting the positional deviation of the positional deviation detection 2S21 to a small value, and a current is applied to the stator 7. As a result, the carrier 1 smoothly moves to the desired stop position in a non-contact manner, and eventually the outputs of one speed detector and the position deviation detector 21 become O, and the carrier 1 is positioned to stop.

The speed signal J that controls the thrust of the stator 7 in this way:
By making the position error signal and position error signal inversely proportional to the small scale of the carrier 1, it is possible to prevent the acceleration of the carrier 1 from being affected by the color tube. This is because the acceleration of an object is generally the value obtained by dividing the force by the mass, and the acceleration of the carrier 1 is the value obtained by dividing the If force applied through the stator 7 by the heavy sound of the carrier 1. Therefore, regardless of the weight of the conveyor 1, the time required to stop and position the conveyor 1 is approximately the same for each conveyor 1, and the conveyance time can be managed well.

Note that the present invention is not limited to the above-mentioned embodiments, and for example, instead of amplifying the speed signal and the position error signal using the amplifier 27, the signal itself outputted from the drive source 9 in a swift manner may be amplified. A similar effect can be obtained.

Further, the ff1l detection means 31 is disclosed in Japanese Patent Application No. 61-59319.
In a system having a branched conveyance path as in No. 1, etc., it may be installed at the tip of the branched conveyance path as described in the above-mentioned prior application.

[Effects of the Invention] As explained above, according to the present invention, sharpening is performed when the speed of the conveying body exceeds a predetermined value based on this speed, and when the speed of the conveying body is less than a predetermined value, the sharpening is performed based on the deviation from the desired stopping position in addition to the speed. Since the thrust is controlled by the conveyor, the conveyor can be accurately stopped at a predetermined position without mechanical braking, and the conveyor can be stopped smoothly without contact, thereby suppressing noise generation. However, since the thrust of the drive source is amplified based on the weight R of the conveyor, it is possible to suppress variations in the time until the conveyor stops due to the size of the base of the conveyor, and it is possible to better manage the conveyance time. can.

[Brief explanation of the drawing]

FIG. 1 is a schematic overall configuration diagram of a conveyance device according to an embodiment of the present invention, FIG. 2 is an enlarged view of a slit and a slit detection means, and FIG. 3 is a time chart. 1...Transportation body 7...Stator 9...Driver 8 Source 11...Slit 13.15...Slit sensor (slit detection means)
One...Speed detector (speed detection means) 21...Position deviation detection 2! i (position deviation detection means) 27...Amplifier (amplification means) 31...Weight detection means

Claims (4)

[Claims] (1) In a conveyance device having a conveyance body, a conveyance path through which the conveyance body moves, and a stator that is provided at a desired interval on the conveyance path and applies thrust to the conveyance body, the conveyance body a slit provided in the conveyance body; a slit detection means provided along the conveyance path to detect the slit; a speed detection means for detecting the speed of the conveyance body based on detection data of the slit detection means; Weight detection means for detecting the weight of the conveyance body; and a drive source that applies thrust to the conveyance body through the stator based on detection data of the weight detection means, the speed detection means, and the position deviation detection means. A transport device equipped with (2) The conveyance device according to claim 1, wherein the weight detection means is provided near the stator. (3) The conveying device according to claim 1, wherein a plurality of the slits are provided in the conveying body. (4) The conveyance device according to claim 1, wherein the slit detection means is provided near the stator.