KR100246524B1 - Method for measuring automatically stop positon of mobile mechanical apparatus - Google Patents

Abstract

The present invention relates to a method for automatically measuring the center interval of a work cell so that the mobile machine can stop working exactly at the center point of the work cell, and is provided at both ends of each cell as the mobile machine moves the cell. A first sensor for recognizing and storing the address of the corresponding cell when the measuring sensor 5 sensing the first and second sensing members 6 and 7 senses the first sensing member 6 of the corresponding cell and is turned on A registration step; Then, from the moment when the measuring sensor 5 is turned off, the counter starts to count the measuring pulse, and the corresponding cell is counted from the counted value until the moment when the second sensing member 7 is sensed and turned on. A second registration step of converting the center interval 9 of the and storing it in the corresponding cell address; When the measuring sensor 5 senses the first sensing member 6 of each cell while moving the moving machine again from the beginning, checks the cell address, and then the measuring sensor 5 turns off. A first counting step of counting the pulses for measurement from the point of time; When the position detection sensor 4, which detects the display plate 2 and holds the position of the mobile machine, detects the plate 2 of each cell and turns it on, the measurement is performed separately from the first counting step. A second counting step of counting pulses; Comparing the value counted in the first counting step with the stored value in the second registration step and storing the counter value of the second counting step as the exact cell pulse data at the corresponding cell address at the corresponding time point; Characterized in that.

Description

Automatic Position Measurement Method of Mobile Machinery

The present invention relates to a method for automatically measuring the exact position of a mobile machine, and more particularly, to a method for automatically measuring the center interval of a work cell so that the mobile machine can work accurately at the center of the work cell.

In mobile machinery, especially in the stacker crane (S / C), which stops at the center point of the cell while moving along the movable rail (1) in a work area composed of a plurality of cells, stops at the center point of the cell exactly. It is very important to do. Here, a cell refers to a unit of an automatic warehouse for storing a load, and a stacker crane stops here to unload or load a load.

Accordingly, as shown in FIG. 1, a plurality of cells are present in the work area, and the stacker crane 3 moves along the moving rail 1 to detect the display plate 2 installed in the center area of each cell. The sensor 4 stops at the correct position by adjusting the speed. The position sensor 4 is a gap type photoelectric sensor having a light receiving unit and a light transmitting unit, which is a kind of photoelectric switch which senses the light path between the light transmitting unit and the light receiving unit by blocking the display plate 2. However, since the display plate 2 stops accurately at the center of the cell through the detection of a large number of errors, a separate means is required.

With this in mind, the present inventors have invented a new method for automatic measurement of exact position and has filed it with Korean Patent Application No. 96-58927. The principle of this measuring method is well illustrated in the flowchart of FIG. 2. Briefly, the cell center interval of all the cells is measured manually, and then the cell center interval, which is 1/2 of the measured value, is PLC 30 (Programmable). Logic Controller) After storing at the corresponding cell address of internal designated memory, move the stacker crane (3) and counter the measurement pulse corresponding to the center interval (9) of each cell to the stored value stored in the memory. The counter value 20 is counted by the position sensor 4 at the coincidence moment and stored in the corresponding cell address. Therefore, when the stacker crane 3 moves along the movable rail 1 and reaches the target cell, the stacker crane 3 reads the pulse value stored at the address corresponding to the cell and starts from the moment when the position sensor 4 is turned on. Moving and stopping by the read pulse value could reach the cell's center point exactly.

However, the conventional automatic position measurement method of the conventional method is not only cumbersome because the operator must measure the cell interval of each cell and store it in the corresponding cell address, and also cannot overcome the measurement error that may occur due to manual measurement. Was present.

Therefore, the present invention was devised to solve the problems of the prior art as described above, and an object of the present invention is to perform automatic measurement of a fixed position, which can be automatically performed by a mobile machine without the measurement and registration of each cell. In providing a method.

Automatic position measurement method of the present invention for achieving the above object is a measuring sensor for sensing the first and second sensing members (6 and 7) installed at both ends of each cell as the mobile machine moves the cell ( A first registration step of detecting and storing the address of the corresponding cell when 5) senses the first sensing member 6 of the corresponding cell; Then, from the moment when the measuring sensor 5 is turned off, the counter starts to count the measuring pulse, and the corresponding cell is counted from the counted value until the moment when the second sensing member 7 is sensed and turned on. A second registration step of converting the center interval 9 of the and storing it in the corresponding cell address; When the measuring sensor 5 senses the first sensing member 6 of each cell while moving the moving machine again from the beginning, checks the cell address, and then the measuring sensor 5 turns off. A first counting step of counting the pulses for measurement from the point of time; When the position detection sensor 4, which detects the display plate 2 and holds the position of the mobile machine, detects the plate 2 of each cell and turns it on, the measurement is performed separately from the first counting step. A second counting step of counting pulses; And comparing the value counted in the first counting step with the stored value in the second registration step and storing the counter value of the second counting step at a corresponding time at the corresponding cell address.

Other objects and advantages of the invention will be described below and will be appreciated by the practice of the invention. Furthermore, the objects and advantages of the present invention can be realized by means and combinations indicated in the appended claims.

1 shows a schematic working state diagram in which a mobile machine moves along a moving rail.

Figure 2 shows a flow chart according to the conventional method for measuring the exact position.

3 is a block diagram of an automatic position measuring device of the mobile machine according to the present invention.

4A and 4B illustrate a flowchart according to the method for automatically measuring a position of the present invention.

<Explanation of symbols for the main parts of the drawings>

4: Position sensor 5: Measurement sensor

6: first sensing member 7: second sensing member

8: cell spacing 9: center cell spacing

10: encoder 20: counter

30: PLC 40: sensor unit

50: inverter 60: motor

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. 3 is a block diagram of an automatic position measuring device of a mobile machine according to the present invention, and FIGS. 4A and 4B show a flowchart according to the method for automatically measuring the exact position of the present invention.

In the description of the present invention, like reference numerals designate like parts throughout the drawings.

Prior to describing the measuring method of the present invention, the measuring device will be briefly described with reference to FIGS. 1 and 3.

At the lower end of the stacker crane 3, a position sensor 4 for detecting the display plate 2 is attached, and for measuring the sensing members 6 and 7 at a predetermined position of the stacker crane 3. The sensor 5 is installed. Here, the sensing members 6 and 7 refer to rack posts for sensing installed at both ends of the cell. One side of the sensing member at both ends of the cell is called the first sensing member 6 and the other side is called the second sensing member 7. If the stacker crane 3 moves in the forward direction (cell # 1 → cell #M), the first sensing member 6 is detected first, and the remaining second sensing member 7 becomes the first sensing member 6. The sensing member serves to divide the cell from the cell and reflect the light projected from the measuring sensor 5 to operate the sensor. The measuring sensor 5 is a type of photoelectric switch that is a reflective photoelectric sensor that operates by capturing a change in intensity of reflected light. Therefore, when the stacker crane 3 moves along the rail 1, the measuring sensor 5 is turned on / off by the sensing member, and the position sensor 4 at the lower end is also turned on / off by the plate.

Referring to FIG. 3, a pulse signal for measurement generated by the encoder 10 is input to the counter 20 and counted, and the counted value is stored in the internal memory of the PLC 30. It is made according to the negative operation signal. The sensor unit 40 is composed of a measuring sensor 5 and a position sensor (4). On the basis of the pulse data stored in the memory, the PLC 30 achieves the position control by driving control of the motor 60 of the stacker crane 3 through the speed adjusting inverter 50.

Therefore, after the position detection sensor 4 detects the display plate 2 at the corresponding cell address of the PLC 30, the pulse data about how much pulse value reaches the center point of the cell (hereinafter, " It can be seen from this that the PLC 30 can position the stacker crane 3 in place by adjusting the speed of the stacker crane 3 if it is stored. In addition, the exact position pulse data is pulse data for the center interval 9 of the cell, which is obtained by the measuring sensor 5 operating and returning by sensing the sensing member (hereinafter, referred to as "measurement pulse data"). It can also be found that it can be obtained by synchronizing with.

Hereinafter, the in-situ measuring method of the present invention will be described in detail with reference to FIGS. 4A and 4B.

First, when the stacker crane 3 starting from the starting point moves to the slow speed in the forward direction, the measuring sensor 5 is turned on by sensing the first sensing member 6 of the first cell. At this time, the PLC 30 designates a cell address corresponding to the first cell in its internal memory. When the designation of the cell address is completed, the stacker crane 3 moves in a small manner, causing the first sensing member 6 to overshoot, and the measuring sensor 5 operated at this time is returned and turned off. As soon as the measuring sensor 5 is turned off, the measuring pulse from the encoder 10 is countered, and the stacker crane 3 passes through the cell so that the measuring sensor 5 receives the second sensing member ( 7) The pulse data corresponding to the cell interval 8 is obtained by stopping the counter as soon as it is detected and turned on. The pulse data is divided into two in the calculating part of the PLC 30, converted into pulse data corresponding to the center interval 9 of the cell, and then stored in the designated cell address. In this manner, the pulse data of the cell center interval corresponding to the cell address of each cell can also be obtained and stored for the cell # 2 and the cell # 3.

When the above-described process is completed in the last cell, the stacker crane 3 is returned to the starting point and then finely operated in the forward direction again. In this case, not only the measuring sensor 5 of the sensor unit but also the position sensor 4 are prepared to operate. When the stacker crane 3 moves and the measuring sensor 5 senses the first sensing member 6 of the first cell, the PLC 30 reads the pulse data stored in the corresponding cell address and applies it to the comparator. do. When the stacker crane is minutely moved and the measuring sensor 5 is turned off, the measuring pulse from the encoder 10 is countered at that moment and compared with the reference pulse data applied to the comparator. If the counter value is smaller than the reference pulse data, the counter of the measurement pulse (hereinafter referred to as "measurement counter") is continued. On the other hand, when the stacker crane (3) moves the cell to reach the display plate (2), the position sensor 4 is turned on, and accordingly, the pulses for measuring the encoder 10 are separately counted. Is called. When the stacker crane 3 moves and the measurement counter value reaches a point (center point of the cell) that matches the reference pulse data, the PLC 30 stops the exact position counter and applies the countered pulse data. Save to cell address and register.

By performing the above process from the second cell to the last cell, the "position counter" value is registered in the cell address of each cell.

The " position counter " value indicates how much the pulse position reaches the center point of the cell after the position detection sensor 4 of the stacker crane 3 detects the display plate 2 of the cell. . Therefore, when the position sensor 4 of the arbitrary cell is turned on, the PLC 30 reads the value of the "position counter 20" from the cell address and counts the pulse from the encoder 10. Stopping the stacker crane 3 at the moment of coincidence allows the cell to be positioned in position.

For example, suppose that the exact position counter value of 12 is stored in the Nth cell address, which is the target cell, and the stacker crane 3 is moved to measure the number of ON position detection sensors 4 to be turned on. When it reaches, the PLC 30 reads 12 stored in the cell address of the corresponding cell. At the same time as reading, when the encoder 10 pulse is countered and the counter value reaches 12, the drive of the motor 60 is cut off and the stacker crane 3 stops. At this time, the position where the stacker crane 3 stops becomes the center point of the target N-th cell.

Although the stacker crane has been described above by way of example, the present invention is not necessarily limited to the stacker crane and can be applied to any mobile machinery suitable for the technical concept of the present invention.

In addition, the present invention is not limited to the above-described embodiment, and various modifications within the equivalent scope of the technical spirit of the present invention and the claims to be described below by those skilled in the art to which the present invention pertains. Of course, variations are possible.

As described above, the present invention enables the mobile machine to automatically perform the process of measuring and registering the center interval of the cell without humans, thereby reducing the inconvenience and measurement error, thereby keeping the load in the correct position. It is effective to prevent falling of cargo.

Claims (4)

In a mobile machine for dividing a work area into a plurality of cells and performing work at the center of each cell, As the moving mechanism moves the cells, when the measuring sensor 5 sensing the first and second sensing members installed at both ends of each cell senses the first sensing member 6 of the corresponding cell, A first registration step of recognizing and storing the address of the corresponding cell; Afterwards, the center interval of the corresponding cell is measured from the count value from the moment when the measuring sensor 5 is turned off to the counting pulse by sensing the second sensing member 7 by counting the measuring pulse. A second registration step of converting (9) and storing it in the corresponding cell address; When the measuring sensor 5 senses the first sensing member 6 of each cell while moving the moving machine again from the beginning, checks the cell address, and then the measuring sensor 5 turns off. A first counting step of counting the pulses for measurement from the point of time; When the position detection sensor 4 which detects the display plate 2 and holds the position of the mobile machine is detected and turned on by detecting the plate of each cell, the measuring pulse is counted separately from the first counting step. A second counting step; Comparing the value counted in the first counting step with the stored value in the second registration step and storing the counter value of the second counting step as the exact cell pulse data at the corresponding cell address at the corresponding time point; Position automatic measurement method of a mobile machine, characterized in that. The method of claim 1, And a counter pulse value corresponding to the center interval (9) of the cell corresponds to 1/2 of the count value countered in the second registration step. The method of claim 2, Method for automatically measuring the position of the mobile machine, characterized in that the measuring sensor (5) is a reflective photoelectric sensor. The method of claim 2, Method for automatically measuring the position of the mobile machine, characterized in that the position sensor (4) is a gap type photoelectric sensor.

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