JP2000255785A - Multiple tiering method for coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure the safety of coil staking in tiers and the freedom degree of the carrier by assuming the partial tierred loading comprising only a triangle with a coil to be mounted on a skid set to the vertex and a coil already mounted thereon set to the bottom side and calculating reactions generated in the contact points of the coils. SOLUTION: When coils are stacked on a skid in tiers and a coil C6 is mounted on the second tier or higher, it is assumed to be a partial tierred loading comprising only a triangle with the coil C6 to be loaded set to a vertex and coils C4, C5 already mounted thereon set to a bottom side. Respectively reactions F1-F12 generated in respective contact points between respective coils C1-C3 and the skid, or the respective coils C1-C6 to each other are calculated respectively. After that, only when the calculated value satisfies a following equation: 0 <= F <= conditions of coil withstanding load, the coils are loaded thereon. That is to say, the dimension of the reaction F must be from 0 to the coil-withstanding load. This constitution can load the coils in tiers without generating load shifting.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention does not cause collapse of stacking loads when loading or unloading coils from or to a coil storage using an automatic crane. And a method for stacking such coils.

[0002]

2. Description of the Related Art A coil manufactured in a hot rolling line or a cold rolling line is usually stored in a coil storage. Also, in the coil center where the coil is processed, unloading of the coil from the coil storage to the processing line,
For example, the return of the coil which is not the full amount processing from the processing line to the coil storage is performed. 2. Description of the Related Art In recent years, in a coil storage, an overhead crane in a coil storage building has been designed to be an automatic crane, thereby saving labor in coil transfer equipment. In order to automate the coil transfer equipment, it is necessary to formulate a coil storage management method that has conventionally relied on the intuition and experience of the crane pilot, and describe it as a computer program. The computer manages the position coordinates and size of the skid in the coil storage area, or the coil information such as the position coordinates, width length, outer diameter, inner diameter, and weight of the coil, and a transfer instruction to be transmitted to the automatic crane (transfer of the coil) (Including information on the position coordinates of the source and the destination) and planning and drafting of the coil transfer procedure.

[0003]

In the planning and drafting of the transfer procedure, it is necessary to finally determine the transfer source and the transfer destination, which are the information contained in the transfer instruction. In order to determine the transport source, it is necessary to extract coils that can be the transport source and check whether the coils can be removed. To determine the transfer destination, it is necessary to extract possible transfer destination positions based on the data of the transfer source coil and check whether the transfer source coil can be placed at those positions. There is.

[0004] In order to check whether or not a coil that is a candidate for a transfer source can be removed, check the mechanical conditions such as whether buckling deformation of another coil or collapse of the stacking load occurs by removing the coil. I do. To check whether the source coil can be placed at a position that is a candidate for the destination, it is assumed that the source coil is placed at that position. In addition to dimensional conditions such as not interfering with the stack or exceeding the height limit of the stack, buckling deformation of other coils and collapse of stack load occur by placing the coil at the transfer destination at that position Check the mechanical conditions such as whether or not to do. However, the method of describing mechanical conditions is not always established.

[0005] By the way, a coil that can be a transport source is a coil in which another coil does not exist in the upper stage, but when the coil is unconditionally taken out, load collapse may occur. Therefore, it is basically necessary to check the mechanical conditions for the coil that is a candidate for the transport source. A coil whose stacking collapses due to removal can be considered as a coil whose movement is actually prohibited, but when such a coil must be removed, movement is prohibited first. By moving a certain coil located in the vicinity of the coil, the movement-inhibited coil can be taken out thereafter. However, complicated logic is required to specify a coil that is in the vicinity of the movement prohibition coil and cancels the movement prohibition.

If there is a coil stacking method that does not generate a movement-inhibited coil, it is unnecessary to specify a coil near the movement-inhibited coil to cancel the movement inhibition and to search for a destination of the coil. become. Further, the configuration of the logic for planning and drafting the coil transfer procedure is simplified, and the generated transfer plan is also highly flexible. SUMMARY OF THE INVENTION An object of the present invention is to provide a method of stacking coils in which a movement-inhibiting coil is not generated, thereby ensuring the stability of stacking and the freedom of conveyance.

[0007]

SUMMARY OF THE INVENTION The gist of the present invention is that when a coil is to be mounted at a certain position on the second or higher stage of the coil stacking, the coil to be mounted is set to the top. Assuming partial stacking consisting only of triangles with the coil already placed on the skid as the base,
At that time, the reaction force F generated at the contact point between the coil and the skid or between the coils is calculated, and the coil is placed only when the value satisfies the condition of the following expression, thereby causing the collapse of the stacked load. Do not let it. O ≦ F ≦ Coil withstand load

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a situation in which when a coil CO (hereinafter, the coil is omitted) is taken out, a load collapse occurs at C2. Here, CO is a movement inhibition coil, and C1 is a coil for canceling the movement inhibition.
CO was not a movement-inhibited coil from the beginning.
It can be said that when the 1 was placed at this position, the CO became the movement inhibiting coil. Therefore, C that generates the movement inhibition coil
It is sufficient to prohibit the placement of the coil such as 1.

Whether or not the placement of C1 generates a movement-inhibiting coil is determined by considering a partial stacking consisting of only triangles having the vertices at C1 as shown in FIG. It is sufficient to verify whether or not occurs. If the partial stacking is self-supporting without collapse of the load, no movement-inhibiting coil is generated. Conversely, if load collapse does not occur in the entire stacking even though the partial stacking collapses, it is considered that a movement prohibition coil is generated outside the partial stacking. There must be. Every time a new coil is placed, the independence of the partial stacking is ensured, that is, if the stacking of the coils is performed while confirming that no movement-inhibited coils are generated, the Don't worry about the collapse.

[0010] A mechanical check to determine whether or not the partial stacking is self-sustaining is performed by first examining whether a coil and a skid or a contact point between the coils is generated in a direction perpendicular to the coil surface. Start by seeking strength. The magnitude of the reaction force is unknown, but its number is given by the number of coils × 2. Using information stored in the computer, such as the position coordinates and size of the skid, and the position coordinates, width, outer diameter, inner diameter, and weight of the coil, the position coordinates of each contact point and the reaction force generated at each contact point act. The direction to be performed can be calculated geometrically.

For example, in FIG. 3, when the magnitude (unknown number) of the reaction force acting on C2 from C1 is F, the y component and the z component of the reaction force acting on C1 are given by the following equations. Y component of reaction force acting on C1 = −F × (y2-y1) /
Ｚ (y2-y1) ² + (z2-z1) ² z-component of reaction force acting on C1 = −F × (z2-z1) /
√ (y2-y1) + (z2-z1) ²

The frictional force generated at each contact point in a direction parallel to the coil surface is negligible with respect to the reaction force. Since the reaction force at the contact point is perpendicular to the coil surface, the moment in each coil is always zero. Therefore, the only equation for deriving the reaction force, which is an unknown, is only the equation of the balance between the y-component and the z-component forces, which are the reaction force acting on the coil and the weight (known number) of the coil. It is given by the number x 2.

FIG. 4 shows a triangular shape having C3 as a vertex when C3 is a coil to be newly mounted.
It is an example of partial stacking of columns. As shown in the figure, since the number of coils is 3, the number of equations is 6, and since the number of contact points is 6, the number of reaction forces is also 6. FIG. 5 is an example of three partial stacks of triangles having C6 as a vertex when C6 is a coil to be newly mounted. As shown in the figure, since the number of coils is 6, the number of equations is 12, and the number of contact points is 12, so the number of reaction forces is also 12. Accordingly, in partial stacking, the magnitude of the reaction force can be obtained by solving a simultaneous equation in which the number of unknowns and the number of equations are equal regardless of the number of stages.

The value of the reaction force F calculated as described above must satisfy the following equation. O ≦ F ≦ Coil withstand load That is, the magnitude of the reaction force F generated at the contact point must be between zero and the coil withstand load. When the value of the calculated reaction force is negative, the load collapse does not necessarily occur due to the effect of the frictional force generated in the direction parallel to the coil surface at each contact point, but the stacking becomes unstable This means that such a coil is not placed. Also, if the reaction force exceeds the load resistance of the coil, buckling of the coil may occur, and in some cases this may cause collapse of the load. I do.

The method of calculating the load resistance of the coil at this time will be described. The coil is regarded as a curved beam having a circular shape, and the width of the beam is defined as the length of the coil and skid or the length of the portion where the coils contact each other. When a load is applied to both ends of the beam, the coil is subjected to a load such that the stress generated at the point of application of the load on the coil surface is calculated as 0.5 kgf / mm ² (actual value). That is, the coil withstand load is given by the following equation.

[0016] Here, R = (outer diameter of coil + inner diameter of coil) / 2 t = (outer diameter of coil−inner diameter of coil) / 2 b = length in the coil width direction in which the coil and the skid or the coils are in contact with each other σ = critical stress value = 5 × 10 ⁵ kgf / m ²

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Skids are fixedly installed at predetermined intervals on the floor of a coil storage where coils are stored, and the position coordinates and size of each skid are registered in a computer. In addition, the center coordinates, plate width,
The thickness, outer diameter, inner diameter, weight, etc. are stored in the computer as coil information. There are several sizes of skids, and the outer diameter of the coil is smaller than the size of the skid, so the coil contacts the floor, and conversely, the outer diameter of the coil is larger than the size of the skid. In order to prevent the coil from becoming unstable on the skid, a coil having a large outer diameter is mounted on a skid having a large size, and a coil having a small outer diameter is mounted on a skid having a small size. Therefore, large-sized skids are arranged at large intervals, and small-sized skids are arranged at small intervals. Therefore, in practice, the coil place is divided into several areas, and the same size skids are arranged in each area, and basically, coils belonging to a certain range in outer diameter and plate width are placed. I have to.

When carrying in or moving a coil, the position at which the coil is to be transported must be determined. However, in the present invention, it is assumed that the coil to be transported has already been determined. The destination of the coil is determined by the procedure shown in the flowchart of FIG.
First, empty skids (skids on which no coil is mounted) are provided as candidates for the transport destination in the first stage of stacking,
Alternatively, at the second or higher stage of the stacking, a position on the surface of the stacking where a coil can be placed is extracted. If the extracted position is the first stage of the stacking, the position coordinates and size of the coil when the coil is mounted on the skid from the position coordinates and size of the skid and the outer diameter of the coil to be mounted Is calculated geometrically, and the dimensional conditions are checked, that is, whether the coil does not interfere with the coil placed on the adjacent skid or the coil does not touch the floor surface, etc. If not, it is excluded from the destination candidates.

If it is the second or more of the extracted stacks, the position coordinates and outer diameters of the two coils which are located below and support the coil to be mounted, and the coil to be mounted From the outer diameter of, the position coordinates of the coil after placement is geometrically calculated, and the dimensional conditions are checked, that is, whether or not it interferes with the coil placed at the next position is checked. Check the mechanical conditions, that is, check whether the partial stack consisting only of triangles with the coil at the destination as the apex and the coil already placed on the skid as the base has autonomy, and do not satisfy this Sometimes, it is excluded from the destination candidates.

From the viewpoint that the coil can be placed on the transfer destination, any position may be selected from the remaining transfer destination candidates, but in the present invention,
One position to be a destination is determined based on an empirical rule. Empirical rules consist of a description of the events that should be preferred to maximize storage efficiency. For example, on the one hand, there is a rule that prefers the placement of the coil so that the step with the coil located next to the stack is as small as possible so that more stacks are possible. There is a rule that prefers the placement of the coil so that the space between the coil located next to the stack and the coil is as small as possible so that a small space is reduced. In the inference part based on empirical rules, the coordination is sometimes formed, and the coordination between these rules is sometimes formed, and the placement position of the coil judged to be the best overall is determined. The function of selecting one is performed.

The computer outputs a coil transfer instruction to the control unit of the automatic crane. The transfer instruction includes the position coordinates of the transfer source coil and the position coordinates of the coil when the transfer source coil is placed on the transfer destination determined in the above procedure. The crane control unit performs safe and stable multi-stacking of coils by moving the crane based on the position coordinates of the transfer source and the position coordinates of the transfer destination received from the computer. The position coordinates of the coil transmitted from the computer shall be treated as coordinates for use in suspending the coil or suspending the coil. This is performed based on signals captured by various detectors mounted on the tool.

[0022]

As described above, according to the present invention, the coil is placed after verifying in advance that the stability of the coil stacking is ensured. Multi-stacking can be performed. In addition, since there is no movement-prohibited coil in stacking, there is no risk of collapse of the load when removing the coil from the destination, so it is possible to freely plan the procedure for moving or unloading the coil. Therefore, it is possible to improve the workability of the crane and increase the efficiency of the work inside the storage space. Further, by adopting rational dynamic conditions, compared with a case where dynamic conditions based on simple rules are adopted, the choices of coil transfer destinations can be expanded, and the efficiency of the storage space can be increased to the limit.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of stacking in which collapse of a load may occur.

FIG. 2 is a conceptual diagram when a partial stack having a coil C1 as a vertex is extracted from the stack shown in FIG. 1;

FIG. 3 is a schematic front view of stacking coils for explaining a direction in which a reaction force acts.

FIG. 4 is a conceptual diagram of partial stacking of two stages.

FIG. 5 is a conceptual diagram of partial stacking of three stages.

FIG. 6 is a flowchart for determining a coil transfer destination.

[Explanation of symbols]

C Symbol attached to coil F Symbol attached to coil and skid, or contact point between coils, or reaction force generated at the contact point

Continued on the front page F-term (reference) 3F029 AA08 BA04 DA02 3F204 AA02 CA01 DA03 DA08 DB04

Claims (1)

[Claims] 1. A skid (coil mounting table) is arranged at predetermined intervals on the floor of a coil storage where coils are stored, and the position coordinates and size of each skid are registered in a computer, and the position of the coil in the coil storage is registered. In an automatic coil transfer system in which position coordinates, width, outer diameter, inner diameter, weight, etc. are stored as coil information in a computer, when placing a coil at a certain position on the second or higher stage of coil stacking Assuming a partial stacking consisting only of triangles with the coil to be mounted as the top and the coil already mounted on the skid as the base, the occurrence occurs at the point of contact between the coil and the skid or between the coils at that time By calculating the reaction force F and laying the coil only when the value satisfies the condition of the following equation, the collapse of the stacked load can be prevented. A multi-layer stacking method of coils, characterized in that: O ≦ F ≦ Coil withstand load