JPS627118B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a crane control device that detects the height of piles of stacked slabs, plate thicknesses, etc. stacked in multiple stages.

In general, in yards where plate-shaped slabs, plate thicknesses, etc. are stocked, a crane as shown in FIG. 1 is used to handle the objects to be transported, and these are stacked in multiple stages as shown in FIG. 2. In order to properly manage production and logistics, the storage location of these objects to be transported, information on the items to be stacked there, and the height of the pile are stored in a computer that manages the yard.

Figure 1 is an overall view of the crane, where 1 is the crane body (girder), 2 is the trolley, 3 is the hoisting device,
4 is a traversing device, 5 is a traveling device, and 6 is a lifting device, which in this case is a lifting net. 7 is an object to be transported, 7a is an object to be transported in a lifted state, 7
b shows objects to be transported in a multi-tiered state. Now, the traveling device 5 is in the direction of X on the drawing, and the traversing device 4 is
moves in the Y direction, and the hoisting device 3 moves in the Z direction.

FIG. 2 shows a state _in which the plate-shaped objects 7 are piled up in multiple _stages by the crane shown in FIG _.
It has a height of _j .

By the way, as mentioned above, in such stockyards, it is becoming important to understand the height of piles at each location from the viewpoint of production and logistics management. Conventionally, the height of these piles has been managed by the total thickness of each board piled using a yard management computer.
However, there was a problem that the height differed from the actual height due to errors in plate thickness, warpage, etc.

This invention attempts to detect the actual height using a hoisting shaft position detecting device, a ground cutting detecting device, a suspended load detecting device, etc. of a crane.

FIG. 3 is a configuration diagram showing an embodiment of this invention.
1 to 7a and 7b are the same as those in FIG. 1, and the transported object 7a has a thickness t _a , and the transported object 7b is a pile stacked in multiple stages on the ground, and each has a thickness t ₁ and t ₂ . ,t ₃
......and the total height is h ₁ . Here _{, the} sum _of the thicknesses t ₁ +t ₂ +t ₃ . 10 is directly connected to the hoisting device and has a lifting device 6
11 is a position detector for the transverse axis, and 12 is a position detector for the traveling axis. Each position detector 10, 11, 12 can be realized by a synchro resolver, a shaft encoder, a nearby switch, or the like. 13 is the hanging tool 6 or the hanging tool 6
A load cell or the like is used as a ground cutting detection device for detecting that the lower surface of the transported object 7a has broken off from the upper surface of the multi-stage pile 7b on the ground. Reference numeral 14 denotes a suspended load detection device for detecting the load lifted by the lifting tool 6. In this example, the lifting tool 6 is provided with a limit switch for detection, but it can also be realized by a load meter or the like.

FIG. 4 is a block diagram of the control device constituting the present invention, FIG. 5 is a diagram explaining the state of pile height detection, and FIG. 6 is a flowchart showing the operation of FIG. 4.

In Fig. 4, 15 is a hoisting signal switch;
It is turned on by the hoisting operation of the crane. Reference numeral 16 denotes a plate thickness signal having a value of the plate thickness _{t a} of the transported object 7a, which is known in advance, and can be obtained by being given from a yard management computer or by setting with a digital switch from an operation panel. 17 is the error correction amount t
The error correction amount signal is represented by _c and is held as a constant of the control device. 18 is each position detector 10,
This is an axis position detection device that converts the electrical quantities obtained in steps 11 and 12 into digital quantities, and can be omitted if each position detector 10, 11, 12 can be directly obtained as a digital quantity. Reference numeral 19 denotes a position-based pile height storage device that stores pile heights for each correspondence between the horizontal plane positions X and Y described above.

Figures 5a to 5d show the height of the stack corresponding to the work of the crane, and Figure 5a shows the state before the crane goes to grab it, and the height h ₁ = t ₁ + t ₂ + t ₃
+t _a and a plate with thickness t _a is about to be lifted. Figure 5b shows the state at the moment the crane picks it up, and the height is h ₁ = t ₁ + t ₂ + t ₃ , which is equal to the detected hoisting shaft position value Z minus the thickness t _a . . Figure 5c shows the state in which the crane is lifting a plate with thickness t _a and before it is lowered, h ₁ = t ₁ +
t ₂ + t ₃ . Figure 5d shows the state at the moment the crane hoists up the load after unloading, and the height h ₁ = t ₁ + t ₂
+t ₃ +t _a , which is equal to the hoisting shaft position detection value Z. Although the error Δh due to the state of the plate is omitted in FIG. 5, it is included in the above _h1 .

Incidentally, in FIG. 5, the timing for detecting the pile height is when the ground cutting detection device 13 operates during hoisting, in both cases of grasping and unloading, and if the hanging load detection device 14 is operating, the stack height is detected. This is the later hoisting, and the pile height at this time h ₁ =Z−t _a
is required. Furthermore, if the suspended load detection device 14 is not operating, the hoist is being hoisted after being unloaded, and this is determined by the stack height h ₁ =Z at this time.

As a result of the above, the appropriate pile height can be set at the end of each work.
h ₁ can be obtained, but in reality, the pile height h ₁ appears somewhat larger due to the operation delay of the ground-cut detection device 13 and the control delay of the shaft position detection device 18, so an error occurs from the actual height. Therefore, the detected value h ₁
A more accurate value can be obtained by subtracting the error correction constant t _c from the value h ₁ ' as the pile height.
FIG. 6 is a flowchart summarizing the above-mentioned contents.

Next, FIG. 7 is a diagram showing the configuration and stored values of the pile height storage device, in which a matrix is constructed corresponding to each position of the traveling axis X _i and the transverse axis Y _j , and each position X
The pile height Z _ij is stored for each _i and Y _j . Note that Z _ij is the value h ₁ '.

In the above embodiment, a lift magnet is used as the hanging tool 6, but a lifting tool such as tongs may also be used.

As explained in detail above, this invention detects the height of the hoisting tool of the hoisting shaft at the time of breaking the ground during hoisting, subtracts the plate thickness from the height when hoisting, and when lowering the hoist. Since the height of each multi-level pile is detected from the height of the shaft hanging tool, highly accurate pile height can be obtained and accurate control can be performed. Further, when using a value obtained by subtracting an error constant, there is an advantage that more accurate control is possible.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the entire crane, Fig. 2 is a perspective view showing a state in which objects to be transported are stacked in multiple stages, Fig. 3 is a block diagram showing an embodiment of the present invention, and Fig. 4 is a control diagram of Fig. 3. The configuration diagram of the device, Figure 5 is a diagram explaining the state of stack height detection, Figure 6 is a flowchart explaining the stack height detection operation, and Figure 7 is the configuration of the stack height storage device and stored values. FIG. In the figure, 1 is the crane main body, 2 is a trolley, 3 is a hoisting device, 4 is a traversing device, 5 is a traveling device, 6 is a hanging device, 7 is an object to be transported, 10, 11, 12 are position detectors, 13 14 is a hanging load detection device, 15 is a hoisting signal switch, 16 is a plate thickness signal,
17 is an error correction amount signal, 18 is an axis position detection device,
Reference numeral 19 is a position-based pile height storage device. In addition,
The same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. In a control device for a stack of plate-shaped objects to be transported stacked in multiple stages and a crane that handles them, a transverse axis position detector for detecting the position of the crane on a plane and a traveling axis. a shaft position detector, a hoisting shaft position detection device for a lifting tool, a ground-off detection device for detecting that a lifted object has broken off from the top surface of the multi-tiered pile, and a hoisting device for detecting the lifting shaft position of a lifting tool; It has a hanging load detection device that detects a load, and a position-corresponding pile height storage device that stores the top surface height of the multi-stage pile in correspondence with the position on the plane,
When the ground breaking detection device operates during hoisting operation and the suspended load detection device is operating, the value obtained by subtracting the thickness of the lifted object from the detection value of the hoisting shaft position detection device. is the height of the multi-stage pile, and when the suspended load detection device is not operating, the detected value of the hoisting shaft position detection device is stored as the height of the multi-stage pile in the position-corresponding pile height storage device. A crane control device equipped with a pile height detection device. 2. A crane control device with a pile height detection device according to claim 1, wherein the pile height stored in the position-corresponding pile height storage device is a value obtained by subtracting an error constant. .