JPS63247297A - Method of controlling overhead travelling crane - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for controlling an overhead traveling crane, and in particular to a method for controlling an overhead traveling crane, in particular, dividing a storage yard into a plurality of sections, assigning an address to each section, and monitoring the inventory status of stored goods. This invention relates to a method of controlling an overhead traveling crane using a computer system that manages each address and controls an overhead crane for transporting stored goods.

[Conventional technology]

Conventionally, the control method for this type of overhead crane places too much emphasis on safety, so the load is hoisted up to a height that is absolutely safe to avoid obstacles on the transport route, and then the crane moves and traverses at will. It was being transported to the destination area.

[Problem that the invention seeks to solve]

The conventional overhead crane control method described above does not take operational efficiency, energy saving, etc. into consideration, and therefore has the drawbacks of a long duty cycle and wasteful power consumption.

Means for Solving Problem C) In the overhead crane control method of the present invention, when transporting a load from an arbitrary address A to another arbitrary address B, first, both areas of address A and address B are transported. Define a belt-like area that connects the openings straight,
All the addresses where all or part of the area and the section overlap are detected, and then, for these detected addresses and address B, the division line of the address at the height of the stored goods stacked at each address is determined. Calculate the positive or negative elevation angle from the horizontal plane of the surface viewed from the moving direction side of the lot line at the height of the stored goods excluding the transported materials at address A. Then, select the address C that has the maximum elevation angle among them, and then set the heights of the stored goods excluding the transported materials at addresses C and A, respectively, as hC and ha, and calculate the difference between them h(-hc-ha). The time th required to hoist the load or the time 1° required to lower the load are calculated from the maximum hoisting or lowering speed and their acceleration/deceleration. Determine the ratio of the crane's running speed and traversing speed and the ratio of their acceleration/decelerations to be equal to the ratio of the direction distance and the width direction distance, and calculate the maximum combined crane speed U having these ratios after the crane starts moving. Calculate the time t u for the composite speed U to rise, and use the time tu to find the time tcl until the load reaches the compartment line at address C or the time tc2 until the load reaches the compartment line at address C. After that, first, start hoisting the load and perform hoisting by a certain hoisting correction amount Δh. Next, if the height hc is greater than or equal to the height ha, th
When ≦trI, the crane starts moving while continuing to hoist the load, transports the load at the above-mentioned combined speed U, and adjusts the height of the load to that height at the end of lifting. Move the load to the upper part of the compartment at address C while holding it, and tH>te
l, except that the start of crane movement is delayed from the above-mentioned time by the difference between time tI and tel -]
The load is moved in the same way as when th≦tc1 described above, and when the height hC is smaller than the height ha, 1, ≧tc
At the time of 2, the crane starts lowering and moves the crane, and 1. <1C2, the crane starts moving while maintaining the height of the load at ha + Δh, and starts lowering after a delay of tc2 t; in both cases, the load is kept at the height difference ha - Move it to the second part of the section at address C while lowering it by hC, and then perform the same calculation between the section at address C and the section at address B in both cases described above. The load is moved to the next target address section by repeating the other operations except the winding and towing operation by the winding correction amount Δh. Meanwhile, the load is moved from the composite speed U until it is stopped. Calculate the travel or traversal distance of the crane during the time, start decelerating the crane from the point where the load reaches the specified distance before address B, and when the load reaches the section of address B, start the crane movement. Finally, the load is adjusted to the initial correction amount Δ
This is a method of lowering the wire by h.

[Effect]

In this way, we first select an area that overlaps with the strip-shaped area connecting the addresses where the cargo is to be moved, and calculate the height of the stored goods in the destination area from the height of the stored goods in the area where the movement starts. Find the first compartment where there is a stored item with a height that protrudes above the line of sight looking at the height, and there is a safe altitude difference with that compartment.''
Add a correction amount of 1 minute, move the load linearly to the end point section while hoisting or lowering, and mark the section line (
Before reaching the "winding" or "lowering" stage, the same operation is repeated again, avoiding all the obstructing piles of hoardings in the above-mentioned strip,
Loads can be moved at the maximum speed possible over the shortest distance in a straight line.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

Figure 1 shows the address section of a storage yard to which an embodiment of the overhead crane control method of the present invention is applied (the address is not written).
FIG. 2 is a plan view of a storage yard showing a strip-shaped area 1 connecting both sections, which is used for calculations when transporting stored goods from the section with address A to the section with address B according to this embodiment. , FIG. 3, and FIG. 4 are explanatory diagrams of the winding method for different heights of stored goods at address C, respectively.

The storage yard is divided in the longitudinal direction and in the direction perpendicular to the longitudinal direction into a grid of fixed lengths and 81 widths, each section is given a street address, and all stored goods are stored in each section. The inventory is managed by address by a separate computer system (not shown), and at the same time, an overhead traveling crane for transporting stored goods installed in the storage yard is also controlled by this computer system. In other words, the identification codes, sizes, and other specifications of individual stored items placed in each compartment, as well as their stacking heights, are constantly input into a computer system and managed for each address. Optionally used for crane control if necessary. The height of the stored goods in this information can be easily corrected automatically by detecting the landing of the transported load, or manually by monitoring with a CRT or the like.

Next, an explanation will be given of the operation of horizontally holding stored goods using this embodiment in the stored goods yard shown in FIG.

Now, when transporting one designated stored item from the top of the stored items that are piled up at a height of 111 hectares in the block for address B to the top of the stored items that are piled up in the block for address B, first Assuming a straight strip area 1 (the area indicated by the dots in Figure 2) formed by connecting the corresponding corners of each section with addresses A and B with straight lines, this strip area 1 and the section are Select all addresses that overlap in whole or in part.

Next, for each of these selected addresses, the height of the stored goods piled up in each section is searched, and the section at the height ha of the pile excluding the material to be transported at address A where the movement of goods is to start is performed. From the lot line on the moving direction side of the line, calculate the elevation angle (positive or negative) from the horizontal plane when looking at the lot line near address A among the lot lines at the height of the pile of each selected address, and Determine the address with the maximum angle. For example, if the height of the pile at address C in FIG. 3 is hc-hahc, then this elevation angle θ. It is easily understood that is tan-1-a. In this case, among these calculated angles, the elevation angle of address C, then the ratio of the traveling speed and traversing speed of the crane from address A to address C, and the ratio of their acceleration/deceleration, are calculated from address A and address C. It is set equal to the ratio of the distance 1i19a in the longitudinal direction of B and the interval 2b in the width direction. Furthermore, the time required for either the running speed or the traversing speed to reach the maximum speed that can be reached under these conditions is calculated as t.

shall be. Taking into account the time tu, the time t[
: Find I. On the other hand, the difference hc-ha between the heights of the piles at address C and address A is used as the hoisting measure, and from this value, the maximum hoisting speed, and its acceleration/deceleration, the time required for hoisting is 1
．． seek.

Therefore, first, the crane starts hoisting, and after hoisting the load by the set correction amount Δh, (1) th≦tc+
In this case, the crane starts traveling and traversing from address A according to the set acceleration and speed while continuing to hoist the load. Figure 3 shows the case of th"tcI, and when the load is transported while being hoisted, the load has arrived at the lot line at address C when the hoisting is finished after time th, and the height of address C is hc can be cleared by the correction amount Δh, and the load is made to enter above the pile at address C at a constant height.If 1h<1C, the load reaches the division line at address C. The hoisting is completed until the load reaches the height, and the load enters the compartment at address C.

(2) If th > tcI If the operation is as in case (1) above, the load will collide with the pile at address C before the hoisting scale is hoisted. As shown, first, only hoisting is continued, and the traveling and traversing of the crane takes 1 h-1.
c. By starting a long time later, the load can clear address C.

Next, until the load enters the compartment at address C, the maximum angle is determined for each address in the strip area 1 viewed from the center of address C, again as in the first case. In both FIGS. 3 and 4, the elevation angle (negative) of the end point B is the only one that is the largest, so the end point address B is selected and the crane continues to traverse and travel with the load at that height N. The lowering point is determined from the difference between the height hb of the pile at address B and the height hc of the pile at address C at the end point, and the lowering is done in exactly the same way as the calculation in the previous step. It can be calculated by calculating the required time and calculating the distance that the crane travels and traverses until it stops moving during this time. Also,
The point at which deceleration of the composite speed is started can be easily calculated from the remaining traveling or traversing distance between the current position of the load and address B, the traveling or traversing speed, and the respective decelerations.

In this manner, when the load reaches the compartment at address B, it is possible to lower the load by the correction value Δh and place the load.

In the above example, only the address C has a pile that becomes an obstacle, but if there are addresses after address C that have a pile that becomes an obstacle, the goal can be achieved by repeating the same calculation. can.

In actual operation, it is necessary to correct the operating method and calculations for the following reasons. For example, in Figure 3, in order to prevent the materials from rubbing against each other, the area at address C would be held a little higher than the height hC to clear it.
In addition, it is necessary to operate so that it comes directly above address B and lowers a little to place it on the pile of address B at the end point, and when calculating the height to be cleared, a correction term Δh must be introduced. This is made possible by That is, the correction term Δh represents a correction amount that includes all of the measurement error of the load height, safety for collision avoidance, deflection of the suspended load, and the like.

〔Effect of the invention〕

As explained above, in the present invention, when transporting a load from any address A to any other address B in a storage yard using an overhead crane, first look from address A to address B, and check the piles on the way. Select the section where the pile is protruding from the line of sight, hold the load at the height that clears that height, and calculate and control the hoisting or lowering amount and its timing so that the load passes through the section. At the same time, the speed and acceleration/deceleration of the crane's travel and traverse are determined so that the load goes straight from address A to address B on a plane, and the crane is moved. By repeating similar calculations, the load can be transported along the shortest route, which has the effect of shortening the duty cycle of the crane and achieving energy savings.

[Brief explanation of drawings]

FIG. 1 is a plan view showing the address sections of a storage yard to which an embodiment of the overhead traveling crane control method of the present invention is applied, and FIG. 2 is a plan view showing the sections from address A to address B according to this embodiment. A floor plan of the storage yard showing the strip area 1 connecting both compartments, which is used for calculations when transporting stored goods, and Figures 3 and 4 respectively show hoisting methods for different heights of stored goods in the compartment with address C. FIG. 1... Band-shaped area, A, B, C... Address of the section, a... Length in the longitudinal direction of one section, b...
・Length in the width direction of one section, ha...height of the stock pile at address A, hb...height of the stock pile at address B, hc...height of the stock pile at address C, Δh ... Winding correction amount, θ. ...The elevation angle when viewing the lot line of address C (address A side) from the lot line of address A (movement side).

Claims (1)

[Scope of Claims] 1. The storage yard is divided into a plurality of sections in a grid pattern by dividing each of the longitudinal direction and the width direction perpendicular to the longitudinal direction by a certain length, and each section has its own section. Inventory management of these stored items is carried out by constantly recording the types, dimensions, and other specifications of the individual stored items piled up in each address block, as well as their stacking height. A computer system for controlling an overhead traveling lane by constantly inputting the current position of an overhead traveling crane for transporting stored goods installed in a storage yard and controlling the overhead traveling crane, the method comprising: Therefore, when transporting a load from an arbitrary address A to another arbitrary address B, first, address A and address B are transported.
A strip area is defined that connects the two sections in a straight line, and all addresses where all or part of the area overlaps with the section are detected. Next, these detected addresses and address B are stacked in their respective addresses. The lot line on the side closer to address A of the lot lines at the address at the height of the stored goods stored at address A is viewed from the lot line on the moving direction side among the lot lines at the height of the stored goods excluding transported materials at address A. Calculate the positive or negative elevation angle of the surface from the horizontal plane, select the address C with the maximum elevation angle among them, and then calculate the heights of the stored goods at address C and address A excluding the transported materials as h_c and h_c, respectively. As h_a, their difference h(=h_
c-h_a) is the time t_h required to hoist the load
Alternatively, the time t_l required to lower the load is calculated from the maximum hoisting or lowering speed and their acceleration/deceleration, and on the other hand, the crane Determine the ratio of the traveling speed and the traversing speed and the ratio of their acceleration/deceleration, find the maximum crane composite speed u having these ratios, and calculate the time t_u for the crane to rise to the composite speed u after it starts moving. , time t_u is used to calculate the time t_u for the load to reach the lot line at address C.
c_1 or the time t_c_2 until the load reaches the compartment with address C, first, start hoisting the load and perform hoisting by a certain hoisting correction amount Δh, and then calculate the height h_c from the height Greater than h_a or height h_
a, and when t_h≦t_c_1, the crane starts moving while continuing to hoist the load and transports the load at the above-mentioned combined speed u, and when the height difference h is finished hoisting, the height of the load is adjusted to that level. The load is moved to the upper part of the compartment at address C while being held at the same height, and when t_h>t_c_1, the crane movement starts at the time t_h and t_c_
Except for delaying by a difference of 1, the above t_h≦t_c
Move the load in the same way as in _1, and when the height h_c is smaller than the height h_a, t_l≧
At t_c_2, the crane starts lowering and moves, and when t_l<t_c_2, the crane starts moving while maintaining the height of the load at h_a+Δh, and the time difference is t_c_2-t_l. Start lowering with a delay, and in either case, lower the load by height difference h_
Move it to the upper part of the section of address C while lowering it by a-h_c, then in both cases mentioned above, move the section of address C and address B.
A similar calculation is performed between the compartments, and the other operations except for the operation of hoisting by the initial hoisting correction amount Δh are repeated to move the load to the compartment with the next target address. The traveling or traversing distance of the crane during the time from the composite speed u until it is stopped is calculated, and the crane is decelerated from the point where the load reaches the specified distance from address B, and the load is within the section of address B. A control method for an overhead traveling crane, in which the movement of the crane is stopped when Δh is reached, and the load is finally lowered by an initial correction amount Δh. 2. The correction amount Δh is based on the error in the stacking height of stored items,
According to claim 1, the value is set in consideration of safety for avoiding friction and collision between stored items, or the amount of deflection of the crane and the load when the load is suspended from the crane. control method for an overhead traveling crane.