JPS6175267A - Detection of speed for linear induction motor type conveying apparatus - Google Patents

Abstract

PURPOSE:To enable continuous control of the excitation of a stator, by providing elements to be detected arranged alternately in bright and dark colors on a moving body along the movement thereof and a detection means for reflected light thereof arranged in a conveying path to detect the speed of the moving body. CONSTITUTION:A moving body (pallet) 2 is supported movably on a roller 1 and a stator 4 is provided at the upper part of the pallet 2 facing a reaction plate 3 on the undersurface thereof 2. Identification tapes 5a and 5b having bright and dark color parts 6a and 6b alternately in the direction of moving them are arranged adjoining vertically. Then, reflection type photosensors 7a and 7b are provided facing the side of the pallet 2 at specified points of the conveying path facing the side of the pallet 2 and two phases of pulse signals corresponding to the moving speed of the pallet 2 are fed to the stator 4 through a frequency/voltage converter 8, a power conversion controller 9, a speed setter 10 and the like. Thus, a stable speed control of the moving body can be done.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a linear induction motor type conveyance device used for conveying articles in factories, warehouses, etc. Related to speed detection method.

[Prior art]

2. Description of the Related Art Conventionally, as a means for transporting objects in a parts assembly transport line, etc., an LTM type transport device using a single-sided linear induction motor (hereinafter abbreviated as LTM) as a power source has been known. This L T zV type conveyor f'! LIMi7) 1 of the number of films arranged at predetermined intervals along the conveyance path.
Next-side traveling magnetic field generator c (below, stator and trim), and the secondary side conductor (hereinafter referred to as LIMI7), which becomes the mover on the lower surface.
It consists of a pallet (moving body) to which a reaction plate (referred to as a reaction plate) is attached, and a support mechanism such as a roller that is provided on the pallet or a conveyance path and supports the pallet movably along the conveyance path, The excitation of each stator is controlled based on the reduction signal from the sensor installed at each point C on the conveyance path to detect the passage of the pallet, and the pallet is moved to a predetermined position. By this, the objects to be transported that are not loaded on the pallet are transported. In this case, in the acceleration section where the pallet is vertically opposed to the stator, the pallet is
7 JOi. It runs in a running H pattern that alternates between coasting and coasting. Furthermore, when the pallet is placed at a stopping point where a station or the like is provided, a braking force is applied by the stator which is excited in the opposite phase.
Speed R and stop.

[Subvertical point that the invention attempts to solve]

By the way, in the above-mentioned conventional LFM type conveyance device, there is a
With J6, the pallet travels M degrees! ! ! Since continuous detection is not performed, it is not possible to continuously control the excitation of the stator in accordance with the ever-changing traveling distance d of the pallet moving at IJO speed. The drawback was that the speed changed depending on external factors. For example, fL of objects to be transported m loaded on a pallet
If the idleness becomes large, the traveling speed of the pallet will decrease, resulting in a reduction in the cycle time from the delivery of parts to the completion of the product, which is an important point required for product assembly and conveyance lines. The major premise is fundamentally overturned. Here, the traveling speed of the pallet is a! As a method for continuously detecting pallet flooding, a slit plate with multiple slits formed along the direction of pallet movement is installed.
A possible method is to arrange the light projector and the light receiver so as to face each other in the conveyance path with the slit plate P in between, but in this case, there is a drawback that the structure is a double fiber structure.

This invention is based on the above-mentioned circumstances, and is based on an IJ that can continuously detect the traveling speed of pallets with a simple configuration.
The purpose is to provide a speed detection method 5 for a near induction motor type conveyance device.

[A precautionary measure to solve the 14-point problem] In this case, #a moving object is provided, and a detected element is provided in which light and dark colors are alternately stacked along the # moving direction of the detected element. The present invention is characterized in that a detection means for detecting reflected light is arranged in a predetermined dark place on the conveyance path, and the speed of the moving object is detected based on the output of the detection means.

[For production]

This allows the pallet traveling speed to be continuously detected in the section where the pallet is accelerated above the stator, so stator excitation can be continuously controlled in accordance with the ever-changing pallet traveling speed. becomes possible.

〔Example〕

A practical example of the present invention will be described below with reference to the F1 drawing.

FIG. 1 is a schematic diagram of a 1, 1M type conveying device to which a speed detection method according to a fourth example of the present invention is applied. In this figure, l... are rollers provided along the conveyance path, and the pallet 2 is supported movably in the conveyance direction (the direction of the arrow shown in !A) by these rollers. A reaction plate 3 is attached to the lower surface of the pallet 2 as a movable member of the pallet 2, and a reaction plate 3 is attached to the lower surface of the pallet 2 at a predetermined interval. TM stator 4
are arranged vertically to face the reaction plate 3 with a predetermined gap therebetween. Identification tapes 5a and 5b are pasted vertically adjacent to the sides of the pallet 2 along its longitudinal direction, that is, along the moving direction of the pallet 2. In this case, on each surface of the identification tapes 5a and 5b, light-colored portions g6a and dark-colored portions 6b are arranged alternately at regular intervals along their longitudinal direction, and the light-colored portions 6a of the identification tapes 5a are arranged alternately at regular intervals. and the light colored part 6 of the identification tape 5b
A and vt are arranged alternately. on the other hand,
Reflective photosensors 7a and 7b are provided at predetermined locations on the conveyance path, facing the side surfaces of the pallet 2, and detecting the reflected light from the identification tapes 5a and 5b, respectively. These reflective types 7
7?corresponding to the moving speed of the pallet 2 output by the automatic sensors 7a and 7b. : Two-phase pulse signal is F/V (frequency &/
4 corresponding to the moving speed IC of pallet 2 with converter 8
The speed signal S of pressure is converted into 1 power force,! Control device 9
supplied to The sword conversion control device if9 is thyristor 1
F/V power conversion circuit and this thyristor power conversion circuit
Speed signal S1 and setting signal S provided from converter 8 and speed setter 10, respectively! The electric power is supplied to the stator 4 from a control circuit that controls the electric power based on the power source, and controls one pressure of the electric power supplied from the three-phase alternating current source to the stator 4.

In this case, the speed setter 10 is set in advance to the pallet delivery speed, that is, the maximum speed 1 degree, and the power conversion control device 9 receives the speed 1 go number SI supplied from the F/V converter 8 from the speed setter 10. The voltage is controlled to match the supplied setting signal S2 and supplied to the stator 4, and the pallet 20
The driving arrest rate is (XIJ).

With the above configuration, when a sensor (not shown) disposed near the stator 4 detects the passage of the pallet 2, this lateral signal is provided to the force conversion control device Wt9, and thereby, The supply of power from the one-power conversion system sub-device 9 to the stator 4 is started.Next, in the acceleration section where the stator 4 and the pallet 2 face each other vertically, the reflective photosensors 7a and 7b touch each of the identification tapes 5a and 5b. The sources reflected by the bright color portions 6a are detected, and the pulse signals with a period corresponding to the movement speed of the pallet 2 are converted into F/V conversion a.
This F/V conversion signal 8 supplies a one-pressure speed signal S, (, -1) corresponding to the moving speed of the pallet 2 to the power conversion control device 9.Then, the power conversion control device 9 but,
Since the speed signal S matches the setting signal S, that is, the three-phase change occurs so that the traveling speed of the pallet 20 matches the preset pallet delivery speed? M: Controls the voltage of one power supplied from the source and supplies it to the stator 4. From this button, the pallet 2 is vertically opposed to the stator 4 7
In the JII arrest rule, the UJ: is set by the UJ setting 510, is UO-arrested to the specific speed, and is sent out.

According to the embodiment described above, the traveling speed of the pallet 2 can be continuously detected in the IJOi section of the pallet 2, so that the stator 4 can be adjusted in accordance with the ever-changing traveling speed of the pallet being moved. It becomes possible to control excitation continuously, and stable speed control of the pallet 2 becomes an OT function.

In addition, in one example not mentioned above, the identification tapes 5a, 5
This is to detect the traveling direction as well as the degree of travel of the lift pallet 2, which is provided with one pair of reflective type sensors 7a and 7b. Further, the speed detection method according to the above-mentioned embodiment is applied to an LrM in which the reaction plate 3 is fixed along the conveyance path and the stator 4 is attached to the lower surface of the pallet 2.
Of course, it is also possible to apply it to a type transport device.

(Effects) As explained above, according to the present invention, detection elements having light and dark colors arranged alternately along the moving direction of the moving body are provided, and the reflected light of the temporary detection element is detected. A detection means is placed at a location on the conveyance path, and the speed of the moving body is detected based on the output of the detection means, so that the movement in the section where the speed is increased by ml by the stators Lr and W is It is possible to continuously detect the moving speed of the moving object with a +IR sound configuration, which makes it possible to continuously control the excitation of the stator according to the moving speed of the moving object, which improves the stability of the moving object. The effect is that the speed control achieved by the above-mentioned method improves the oJ performance.

[Brief explanation of drawings]

FIG. 7 is a schematic diagram of a linear induction motor type conveying device to which the speed detection method according to the @Ming example is applied. 2... Pallet (moving object), 3...
Reaction plate (secondary side), 4...Stator (primary side), 5a, 5b...Identification tape (
(detected element), 6a...bright color part, 6b...
...Dark color part, 7a17b...Reflection M7 Otose/
(detection means).

Claims (1)

[Claims] A primary side of a linear induction motor is provided on a conveyance path or a moving body movable along this conveyance path, and a second side of a linear induction motor is provided on the moving body or on the conveyance path with a predetermined gap from the primary side. In the linear induction motor type conveyance device, in which the moving body is provided with a next side and a conveyed object is loaded on the moving body and transported, the detected element is arranged in light and dark colors alternately along the moving direction of the moving body. A linear induction motor characterized in that a detection means for detecting reflected light from the detected element is arranged at a predetermined location on the conveyance path, and the speed of the moving body is detected based on the output of the detection means. Speed detection method in type conveyor.