JPS5924716B2 - Automatic selection control device for the number of steel plates to be lifted in a lifting electromagnet device - Google Patents

Description

Detailed Description of the Invention This invention provides a suspension electromagnet device in which a plurality of suspension electromagnets are installed in parallel, and even if the stacked state is a plurality of stacked steel plates with different widths or lengths, the number of steel plates specified in advance can be fixed. The present invention relates to an automatic sorting control device for automatically sorting the number of steel plates to be hoisted by reliably sorting each hoisting electromagnet so that the number is equal to the number of hoisting electromagnets.

As shown in FIG. 1, a plurality of lifting electromagnets LM.

...L'Mn (hereinafter referred to as an electromagnet unit).

: For lifting electromagnets installed in parallel, the width or length of the steel plate that can be lifted depends on the spacing between each electromagnet unit and the length between the endmost electromagnet units (for example, LM and LM5). is determined.

Therefore, it is difficult to simultaneously lift a plurality of steel plates of different widths or lengths, and it becomes difficult to control the excitation current.

Therefore, in the past, it was necessary to provide a pile of steel plates for each steel plate of the same standard (size, etc.). Requiring a large space and performing work separated by L1 standard led to a decrease in work efficiency.

This invention automatically sorts and hangs reliably the number of sheets specified for each electromagnet unit even if the specified number of sheets to be lifted by each electromagnet unit is different due to the mixing of steel plates with different widths or lengths. The purpose of the present invention is to provide an automatic sorting control device for the number of steel plates.

Hereinafter, the present invention will be explained with reference to illustrated embodiments.

FIG. 3 is a block diagram showing an embodiment of the automatic selection control device for the number of steel plates to be lifted according to the present invention.

This control device targets a lifting electromagnet device in which a plurality of electromagnet units LM1 to LM5, each of which can be excited independently, are arranged in parallel, and the entire device lifts a steel plate S.
A lifting number detector that detects the number of steel plates or the sum of plate thicknesses that are attracted by each lifting electromagnet unit for each lifting electromagnet unit (LM1 to LM) with respect to T... P
D1 to PD5, and each electromagnet unit LM1 to LM1 to D5 compare the number of steel plates to be hoisted, which is specified in advance for each electromagnet unit, based on the detection outputs of the lifted number detectors PD1 to PD5.
Excitation current controller FC that individually controls the excitation current of LM,
1 to FC5.

As is clear from the figure, each PD. ~PD, and FC, ~FC
There is a one-to-one correspondence with 5.

First, in the excitation current controllers FC, to FC5, SR,
~SR5 is a rectifier unit composed of a silice, a diode, etc. that supplies DC power, PC1 to PC5 are phase shifters that control the phase of the output of each rectifier unit SR1 to SR6,
CD1-CD are excitation current detectors, ML1-ML are attraction operation contacts of electromagnet units LM, ~LM5, MD1
~MD5 is a contact point for the release operation.

TR indicates a main transformer. Lifting number detector PD, ~PD
, HD1 to HD are each lifting electromagnet unit l-
Magnetic sensing elements embedded in the magnetic poles of LM, ~LM5 (e.g.
Hall elements, etc.) AP, ~AP, are amplifiers, BX1 ~ BX
5 is a large quantity reference value generator, CX1 to CX5 are large quantity comparators,
B.N.

~BN5 is a handhold reference value generator, and CN and ~CN5 are handshake comparators.

A1 to A5 are excitation current signals, 81 to B5 are large quantity plate thickness sum signals, C1 to C5 are hanging plate thickness sum signals, D1 to D are detection timing signals, X1 to X5 are large quantity signals, N1 to N, is the hanging hand signal.

Next, the operation of the automatic sorting control device having the above configuration will be explained.

The excitation current signals A1 to A corresponding to the excitation current for selectively lifting the number of sheets individually specified for each electromagnet unit by a computer (not shown) are supplied to the phase shifters PC1 to PC.
Sent to 5.

At this time, the command from the computer has already been applied to the suction contact ML.
, ~ML, are input.

When the excitation current signals A1 to A5 are sent, the phase shifters PC1 to
The PC5 controls the conduction angle of the rectifier units 1-8R1 to SR, and DC power is supplied from each unit SR1 to SR5 to the electromagnetic units II, M, to LM.

The excitation current is detected by the current detectors CD, ~CD, and fed back to the phase shifters PC1~PC3#, and the excitation current corresponding to the excitation current signals A1~A5 is sent to the electromagnet unit LM.
.

~LM5 is energized.

After this energization, a crane (not shown) is installed.

) to make the steel plate ST...... about 300mm.
Perform ground cutting.

After grounding, the excitation current is reduced to about 7 of the rated current according to the computer command.
0% (hereinafter, this will be referred to as the current value for detecting the number of sheets to be lifted).

). On the other hand, Ichi'Magnet Units I-LM1
~ When an excitation current flows through LM5, the magnetic sensing element HD, ~
HD5 generates an output corresponding to the magnetic flux density of the magnetic pole, and this detected output is sent to amplifiers AP, ~AP5.

Magnetic sensing elements HD, ~HD5 in amplifiers AP, ~AP5
By correcting the variations in the characteristics, the output voltage is the same when the magnetic flux density is the same.

By the way, the relationship between the output voltage e of the magnetically sensitive elements HD, ~HD5 and the sum of plate thicknesses T of the suspended steel plate ST...
When the excitation current of the electromagnetic units t-LM1 to LM5 reaches the current value for detecting the number of sheets to be lifted (approximately 70% of the rated current), the custom-made one has the characteristics shown in FIG. 2.

In other words, even when the sum of the number of steel plates to be lifted is the same, each steel plate ST...magnetic sensing element HD due to differences in plate thickness, number of plates, and stacking order.

~ There are variations in the output voltage of the HD5, and the MAX curve connects the points with the maximum variation, and the MIN curve connects the points with the minimum variation.

Among these curves, 4=WIE corresponding to the MAX curve is set in the hand reference value generators BN, to BN5, and the characteristics corresponding to the MIN curve are set in the large quantity reference value generators BX1 to BX5# by fold line approximation. ing.

Therefore, as shown in Fig. 3, the signal corresponding to the sum of plate thicknesses that is one more than the specified number of plates to be lifted by the lifting electromagnet is the large plate thickness sum signal B, ~B5, and conversely, the signal corresponding to the sum of plate thicknesses that is one plate less than the specified number of plates to be lifted by the lifting electromagnet. The signals corresponding to the hanging plate thickness sum signals C1 to C5 are the large quantity reference value generators BX, ~BX6, and the hanging reference value generators BN1 to BN1, respectively.
This becomes the input for BN4.

The outputs of the large quantity reference value generators BX1 to BX5 are sent to the large quantity comparator C.
The signals are sent to X1 to CX5 and compared with the outputs of amplifiers AP, to AP5.

The output of amplifiers AP, ~AP5 is the large reference value generator BX1.
.about.BX5, large quantity signals X1 to X are output.

On the other hand, the outputs of the lifting hand reference value generators BN, ~BN5 are sent to the lifting hand comparators CN, ~CN, and compared with the outputs of the amplifiers AP, ~AP5, and the outputs of the amplifiers AP1 to AP are used as the hanging hand reference values. When the value is smaller than the outputs of the value generators BN1 to BN5, the hanging hand signals N, -N are output.

Now, when the excitation current of the electromagnet units LM, ~LM, reaches the excitation current value required for sorting and lifting the specified number of sheets to be lifted, the detection timing signals D1 to D5 are ONL, and if there is a lifting failure, the large quantity signal X1 ~X5 or hanging hand signal N1~
N5 is sent to the computer.

The computer that receives the large volume signals X1 to X5 or the lifting hand signals N1 to N5 unwinds the steel plate ST, lands it on the floor, and releases the steel plate ST.

An excitation current signal is applied to the electromagnet unit for which a large quantity signal is detected after release, and an excitation current is set to an excitation current smaller than the previous excitation current, and an excitation current signal is applied to the electromagnet unit for which a hanger signal is detected, to an excitation current larger than the previous excitation current. The current signal is changed to pick up the steel plates again, and the number of steel plates is selected.

Incidentally, the amplifying width and the decreasing width (or rate) of the excitation current are stored in advance in the computer.

To summarize the above control operation and explain it with a concrete example, for example, let the sum of the thicknesses of steel plates for the specified number of lifted steel plates of the electromagnet Units I-LM be T, and the thickness of steel plates when there is one less than this. The sum of the steel plate thicknesses is T2. The sum of the steel plate thicknesses when there is one more plate is T1 (see Figure 2).

). The quantity large plate thickness sum signal B4 corresponding to T1 is sent to the quantity large reference value generator BX, and the hanging plate thickness sum signal C corresponding to T2 is sent to the quantity large reference value generator BX.
4 is sent to the hanger reference value generator BN4, the output eN1 of the large quantity reference value generator BX4 (see FIG. 2).

) is the large quantity comparator CX4, and the lifting hand reference value generator BN4.
The output eX2 (FIG. 2) is sent to the hand comparator CN.

If the electromagnet unit LM4 (the sum of the attracted plate thickness is T
If the output of the magnetically sensitive element HD4 is e, then eN
≦e≦eX, and the large quantity comparator cx.

Then, e and eNl are compared L, and since e < e N , the large quantity signal X4 is not output.

Therefore, it is detected that the electromagnet unit LM4 is lifting the specified number of sheets.

Further, when the large quantity comparator CX4 shows "e≧N+", it clearly means that one more steel plate ST than the specified number has been hung, so a large quantity signal X4 is output.

When the lifting hand comparator cN4 shows "e5eX2", it means that one less steel plate ST than the specified number has been hung, and therefore the lifting hand signal N4 is output.

In this way, the excitation current is increased or decreased to an appropriate value in accordance with the output large quantity signal
・・・・・・・・・ can be lifted.

In addition, in the above embodiment, the number of lifted sheets detectors PD, ~P
Although magnetically sensitive elements HD, to HD5 are used as the detectors of D5, the present invention is not limited to the above embodiment.

For example, the terminal voltage and excitation current of the coil are detected by the correlation between the electric energy input to the excitation coil and the consumed energy using a custom-made magnetic saturation of the magnetic path by each electromagnet unit LM, ~LM5 and the adsorption steel plate ST. It is possible to detect the number of steel plates lifted with just this.

As described above, according to the present invention, even if there is a difference in the number of sheets to be lifted in each electromagnet unit due to the difference in the width or length of each steel sheet, the number of sheets can be detected for each electromagnet unit, and the excitation current can be controlled. As a result, it is possible to reliably lift a specified number of steel plates for each electromagnet unit.

Therefore, when lifting, it is not necessary to select only steel plates of the same standard, and there is no need for a space for stacking the same steel plates, improving work efficiency.

[Brief explanation of the drawing]

Fig. 1 is an elevational view showing the lifting state of various steel plates and the lifting electromagnet, Fig. 2 is a characteristic diagram of the output voltage of the magnetic sensing element with respect to the sum of the plate thicknesses, and Fig. 3 is the number of steel plates to be lifted according to the present invention. FIG. 2 is a block diagram of an automatic sorting control device. LM, ~LM5... Electromagnet unit, PD, ~
PD5...Lifting sheet number detector, FC1 to FC5.
...Exciting current controller, SR1 to SR5...
- Rectifier unit, PC. ~PC5... Phase shifter, CD, ~CD5...
...Exciting current detector, ML, ~ML5... Contact for suction operation, MD. ~MD5...Contact for release operation, TR...Regenerative transformer, HD, ~HD5...Magnetic sensing element, A
P1~AP5...Amplifier, BX, ~BX5...
...Quantity large reference value generator, CX, ~CX5...
・Large quantity comparator, BN, ~BN5... Hanging hand reference value generator, CN, ~CN,... Hanging hand comparator, A1
~A5...Exciting current signal, 81~B5...
・・Large plate thickness sum signal, C1-C5...Hanging plate thickness sum signal, D1-D5...Detection timing signal,
N1 to N5... Hanging hand signal.

Claims (1)

[Claims] 1. In a lifting electromagnet device in which a plurality of lifting electromagnets each of which can be independently excited are arranged in parallel, the number of lifted steel plates or the sum of the plate thicknesses is individually detected for each lifting electromagnet. A number-of-lifted plate detector outputs a hanging plate and lifting hand signal in comparison to the number of steel plates to be lifted, which is specified in advance for each lifting electromagnet, and each lifting electromagnet is An automatic selection control device for the number of steel plates to be hoisted in a hoisting electromagnet device, which is equipped with an excitation current controller that individually controls the excitation current given to each.