JP2523356B2 - Carrying control method for lifting and lowering cranes for loading and unloading - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lifting / lowering control method for a lifting / lowering carriage in a loading / unloading crane that travels along a three-dimensional shelf (rack).

2. Description of the Related Art As a conventional lifting carriage control method for the above-mentioned filling-and-leaving crane, a control method as disclosed in JP-A-61-145001 has been used. That is, a lifting distance measuring means for replacing the position of the lifting carriage with respect to the origin (lower limit) of the lifting carriage with a pulse count value is provided. At the position corresponding to, the lower detected plate whose center height of the upper and lower width corresponds to the stop height at the time of leaving and the upper detected plate corresponding to the stop height at the time of entering are installed side by side, and An absolute address for learning the pulse count value in the ascending / descending distance measuring means when the detector for detecting the detected plate is provided, the elevating carriage is learned and moved up and down, and the detector detects the upper and lower edges of each detected plate In advance, the pulse count value in the ascending / descending distance measuring means when the detector detects the edge of the plate to be detected is replaced with the learning absolute address during actual operation, Between the stop target value which is calculated and stored in advance for each stop height, or which is calculated each time based on a set of upper and lower learning absolute addresses for the target stop height, and the pulse count value in the ascending / descending distance measuring means. The stop control of the moving body is performed based on the difference.

However, in the conventional control method, the error between the up / down distance of the up / down carriage and the pulse count value due to the elongation or load of the up / down chain of the up / down carriage is corrected, and the target stop height is corrected. Although it is possible to stop the lifting carriage at the same time, if there is an error in the relative installation level between the loading / unloading crane and the truss on the shelf, an error will occur between the target stop height and the target shelf storage height, It was not possible to accurately stop the elevating carriage at the target shelf height of the cargo storage unit.

The present invention solves the above problems, and an object of the present invention is to provide a lifting carriage control method for a loading / unloading crane that can accurately control the lifting carriage even at different installation levels.

Means for Solving the Problems In order to solve the above problems, the present invention provides a lift distance measuring means for measuring a distance from a predetermined position of a lift carriage, a predetermined position of the lift carriage, and a bottom load receiving portion of each bay. Between the detection target provided on the truss of each bay, and a detector provided on the lifting carriage to detect the detection target, and stop the lifting carriage for each cargo receiving section of the bay from the predetermined position. The position and the position to be detected are stored in advance by the measured value of the ascending / descending distance measuring means, and the ascending / descending carriage is raised by a certain distance from a predetermined position for each truss, and the detector detects the object to be detected. At this time, the measured value in the ascending / descending distance measuring means is stored, and the difference between the measured value and the measured value of the detection target position from the previously stored predetermined position is used to calculate the value in advance. The measured value of the lifted carriage stop position for each load receiving portion of the bay from the stored predetermined position is corrected.

The level accuracy of the receiving part of the working bay is the installation accuracy of the truss,
It depends on the manufacturing accuracy of the arm and the mounting accuracy of the arm.
Since the one that causes the largest error is the installation accuracy of the truss, the present invention absorbs the error in the relative level between the truss and (the rail of) the loading and unloading crane to raise and lower the carriage to the cargo receiving part of the target bay. It is intended to accurately control the stop of the.

By the control method in the means for solving the above problems, the distance between the predetermined position of the lifting carriage and the detection target provided on each truss is measured, and the relative level error of each bay is recognized by the loading / unloading crane. Then, the measurement value stored in advance for each load receiving portion from the predetermined position is corrected as a target value by correcting the difference between the measurement value measured and the measurement value from the predetermined position stored in advance to the detection target, By controlling the current measured value and this target value to be equal, the lifting carriage is accurately stopped at the target in front of the load receiving portion.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view of a loading / unloading crane and a rack using the raising / lowering carriage control method for the loading / unloading crane of the present invention.

In FIG. 1, reference numeral 1 denotes a loading / unloading crane, which is provided with a lifting carriage 3 that is lifted and lowered by being guided by a column 2.
On the carriage 3, there is provided a running fork 7 capable of laterally moving in and out, which transfers the load 6 to and from each load receiving portion 5 of the rack 4. Reference numeral 8 is a traveling motor that drives the crane 1 to travel along the rack 4, 9 is a lifting motor that drives the lifting carriage 3 up and down, and 10 is a fork motor that moves the running fork 7 in and out. An induction motor that shifts gears is used.

As shown in FIG. 2, the speed of the lift motor 9 is controlled by a dedicated inverter 11, but the travel motor 8
The fork motor 10 and the fork motor 10 are speed-controlled by a traveling / fork inverter 13 which is selectively connected by a switching means 12. The inverters 11, 13 and the switching means 12 are controlled by control signals a, b, c by a control device 14 composed of a microcomputer.

The pulse signals p, q, s from the pulse encoder 17 interlocked with the traveling movement of the crane 1, the pulse encoder 18 interlocked with the up / down movement of the elevator carriage 3 and the pulse encoder 19 interlocked with the withdrawal movement of the running fork 7 are The controller 14 counts the addition and subtraction, reads the current position values of the crane 1, the lifting carriage 3, and the running fork 7, and uses them to control the motors 8, 9 and 10. The presence / absence of the load 6 on the lift carriage 3 is detected by the load detector 20, and the load signal d is input to the controller 14 and used to control the traveling motor 8 and the 6-fork motor 10.

Further, as shown in FIGS. 1 and 3, for each truss 4A of the rack 4, a detection plate 21 is provided between the lowering limit of the lifting carriage 3 and the lowermost load receiving portion 5 of the bay, and The carriage 3 has a light reflecting portion 21A at the center of the plate 21 to be detected.
A photoelectric position detector 22 is provided for detecting the. The position of the lower edge of the light reflecting part 21A of the detection plate 21 from the lower limit of the elevator carriage 3 when the rail 1A of the loading / unloading crane 1 and the truss 4A have no error in the installation level is from the lower limit of the elevator carriage 3. Pulse signal q of pulse encoder 18 of
The pulse count value is set in the controller 14 in advance. In addition, the propeller 2 of the loading and unloading crane 1 is provided with an elevating carriage 3 for each cargo receiving portion 5 of the bay and a detection plate to be corrected for correcting the stop position.
23 is provided, and the light reflecting portion at the center of the corrected detection plate 23 is provided.
A correction position detector 24 for detecting 23A is provided in the ascending / descending carriage 3, and the descending limit and the distance of each of the corrected detection plates 23, that is, the stop position of the ascending / descending carriage 3 for each of the cargo receiving portions 5 of the bay from the descending limit. The pulse count value is preset. This stop position setting pulse count value is the corrected position detector
At 24, the correction is made and reset every time the plate to be detected 23 is corrected, and an error such as extension of a lifting chain (not shown) generated in the loading / unloading crane 1 itself is corrected as in the conventional example.

Hereinafter, a method of controlling the lift carriage 3 by the control device 14 will be described. The traveling control method of driving the traveling motor 8 and the control method of the running fork 7 that drives the fork motor 10 by the control device 14 are not essential parts of the present invention, and a description thereof will be omitted.

The level accuracy of the bay receiving section 5 is the truss of the rack 4.
4A installation accuracy, arm 4B manufacturing accuracy, arm 4B mounting accuracy, etc.
Appear as shown in Fig. 4 with installation accuracy. The present invention is intended to accurately control the stop of the elevator carriage 3 by absorbing the error in the relative level between the truss 4A and the rail 1A of the loading / unloading crane 1.

A method of learning the distance from the lower limit of the raising / lowering carriage 3 of the plate to be detected 21 by the control device 14 will be described with reference to the flowchart of FIG.

First, it is confirmed that the control device 14 has learned the traveling learning, that is, the position in the traveling direction of the loading / unloading crane 1 for each truss 4A (step 31), and the elevator carriage 3 is lowered to the lower limit by the confirmation. The loading / unloading crane 1 is moved to a position where the position detector 22 crosses the detected plate 21 in the vertical direction, and the measurement of the detected plate 21 of the first truss 4A is started (step 32). If the traveling learning is not completed in step 31, the coefficient n is reset, that is, n is set to zero (step 33) and the processing is completed. Next, the truss number is set (step 34), and it is confirmed whether or not the measurement of all trusses 4A (the number of trusses; N) is completed (step 35). If the measurement is not completed, it is first confirmed whether or not the ascending / descending carriage 3 is in the descending limit (steps 36, 37), the pulse count value is reset by the confirmation (step 38), and the ascending / descending distance carriage 3 is raised by a certain distance ( Steps 38, 40). The elevating carriage 3 is raised, and the position detector 22 is moved as shown in FIG.
When the lower edge of the light reflecting portion 21A of the detected plate 21 is detected and turned on, the pulse count value X is stored as the origin address C (n) of the truss 4A (steps 41 and 42). When the ascent is completed, the elevating carriage 3 is moved to the position of the detected plate 21 in the next bay while descending, and when the fixed position is reached, the next measurement is started (steps 43, 44, 45). Then, in step 35, measurement of all truss 4A is completed, and all truss 4A is measured.
C (1), C (2) ... When the origin addresses of C (N) are measured, the absolute origin addresses D (n) of all bays (the number of bays; N-1) are set to the truss 4A at both ends of the bay. Origin address C (n), C (n + 1)
Register with the lower one (steps 46-51). This is the fourth
This is because the origin absolute address D (n) of the bay is selected so that the running fork 7 does not collide with the load 6 because the load 6 leans toward the lower truss 4A as shown in the figure. When all origin addresses D (n) have been registered, n is set to zero in step 33 and the process ends.

Lifting carriage 3 according to the flowchart of FIG. 5 above
The locus Y of is shown in FIG. It is possible to register the absolute origin address D (n) of each bay by learning elevating the elevating carriage 3.

Since the stop position of the elevating carriage 3 for each load receiving portion 5 of the bay is preset by the pulse count value from the lower limit, when the target load receiving portion 5 is input by the command signal e, first, the bay having the load receiving portion 5 is input. This set pulse count value at the stop position is corrected by the difference between the absolute address D (n) of the origin and the pulse count value from the set lower limit to the plate 21 to be detected. Then, by controlling the lifting motor 9 via the inverter 11 so that the current pulse count value and the corrected set pulse count value become equal, the lift carriage 3 is moved to the target stop position of the cargo receiving portion 5 and the truss. 4A and loading / unloading crane 1
There is no error due to the error in the installation level, and the operation can be stopped accurately. As in the conventional example, each time the correction position detector 24 detects the correction target plate 23, the set pulse count value of the stop position is reset.

Effects of the Invention As described above, according to the present invention, the distance between the predetermined position of the lifting carriage and the detection target provided on each truss is measured,
The difference between the measured value and the measured value of the ascending / descending distance measuring means from the predetermined position stored in advance to the detection target is used to measure the elevator carriage stop position of each load receiving portion of the bay from the previously stored predetermined position. Correct the values to absorb the error in the relative installation level between each bay and the loading and unloading crane, and control the current measurement value and the corrected stop position measurement value to be equal to each other, so that the elevator carriage can be accurately adjusted. Even if there is an error in, it is possible to stop before the target load receiving section.

[Brief description of drawings]

FIG. 1 is a side view of a loading and unloading crane and a rack using a raising and lowering carriage control method for a loading and unloading crane showing an embodiment of the present invention, and FIG. 2 is a block diagram of a control system of the loading and unloading crane. FIG. 3 is a block diagram of a lifting / carrying control system of the loading / unloading crane, FIG. 4 is a side view of a main portion of the rack of FIG. 1, and FIG. 5 is a flowchart of a lifting / lowering carriage control of the loading / unloading crane. 6 and 6 are enlarged side views of the plate to be detected of the rack shown in FIG. 1, and FIG. 7 is a locus diagram of the loading and unloading crane during lifting and lowering carriage learning. 1 ... Crane for loading and unloading, 2 ... Pillar, 3 ... Lifting carriage, 4 ... Rack, 4A ... Truss, 5 ... Load receiving part, 6 ... Load, 9 ... Lifting motor, 14 ... Control Equipment, 18
...... Pulse encoder, 21 …… Detected plate, 22 …… Position detector.

Claims (1)

(57) [Claims] 1. A lifting distance measuring means for measuring a distance of a lifting carriage from a predetermined position, and a cover provided on a truss of each bay between the predetermined position of the lifting carriage and the lowermost load receiving portion of each bay. A detection target and a detector provided on the lifting carriage for detecting the detection target, and measuring the lifting distance of the lifting carriage stop position and the detection target position for each load receiving portion of the bay from the predetermined position. It is stored in advance according to the measurement value of the means, and the elevation carriage is elevated by a certain distance from a predetermined position for each truss, and the measurement value in the elevation distance measuring means when the detector detects the detection target is stored. Then, by the difference between this measured value and the measured value of the detection target position from the previously stored predetermined position, the cargo receiving section of the bay from the previously stored predetermined position Lifting carriage control method for goods movements cranes performing the lifting carriage correction of the measurement values of the stop position.