JP2688607B2 - Seed wire position deviation detection device for CZ lifting device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seed wire management device for a CZ pulling device, and more particularly to a device for detecting a positional deviation of a seed wire.

(Prior art and its problems) When using a CZ lifting device, management of the seed wire is extremely important.

During normal operation, since the ingot is pulled up while rotating the crucible, if the rotation center of the crucible and the rotation center of the seed wire are misaligned, the pulling ingot causes an orbital motion and the measured value of the ingot diameter is disturbed, resulting in the ingot. The pull-up diameter of the steel changed and the yield decreased, and also DF (Dislocation Free) discontinuity was sometimes reached.

Therefore, conventionally, marks were made on the periphery of the crucible every 90 °,
Two virtual lines were obtained by connecting points at every 180 °, and the intersection of these lines was regarded as the center of rotation of the crucible.

However, the result of the above centering method is that the accuracy is ±
It was 0.5 mm, and further improvement in accuracy was desired in order to improve the DF ratio.

Further, the seed wire needs to be hung at a proper position at all times.

For example, during operation, the polycrystalline material may be suspended on a seed chuck for additional charging, which may cause the seed wire to sag. Also, when the seed chuck itself is replaced, the seed wire sags and its tension is weakened.

In such work to reduce the tension of the seed wire, the tension of the seed wire will be excessively weakened, the seed wire will come out of the groove of the drum, or the seed wire will be wound around the wire retainer opposite to the drum. As a result, there was a problem that the seed wire was cut.

As described above, control of the drooping position of the seed wire is a very important problem in the CZ operation, and accurate position confirmation detection of the seed wire is indispensable for improving the management of the seed wire.

The present invention has been made for the purpose of proposing a seed wire positional deviation detecting device capable of appropriately managing a seed wire under the above-mentioned circumstances.

(Means for Solving the Problem) That is, the first invention is to detect the positional deviation when the seed wire is deviated from the original position by a predetermined amount, and the seed wire is provided in the conductive cylindrical body. The seed wire and the cylindrical body are configured to be connected to a continuity detector equipped with a warning means, and the seed wire and the cylindrical body are brought into conduction by contact with the cylindrical body to obtain a warning. Is for detecting the positional deviation and the amount of deviation when the seed wire deviates from the original position, and a column-shaped weight is attached as a concentric core to the appropriate position of the seed wire. At least a pair of measuring instruments are arranged on the left and right sides of the measuring instrument, and the measuring instrument is connected to a computing device and a display device, and the positional deviation is detected by performing a computation based on the difference in each distance between the weight and the measuring instrument. To do.

(Operation) In the first invention, the seed wire is usually positioned in the center of the cylindrical body, and the seed wire is displaced during the operation or replacement of the seed chuck, and the seed wire becomes the cylindrical body. If contact is made, a warning will be issued. Therefore, the position at which it is dangerous to further shift the position should be set to be the maximum value of the inner diameter of the cylindrical body.

In the case of the second invention, when the lifting device is disassembled and assembled, the seed wire shift amount is measured and applied to the assembly adjustment work of the lifting device, and the method is the distance between the weight and each measuring instrument. a, b
When the seed wire is located in the center between the measuring devices, a and b are equal, but the amount of positional deviation when the positional deviation occurs is (ab) / 2 (however, a> b). This position shift amount is calculated by the calculator, and the result is shown on the display. As a result, it is possible to detect the positional deviation and the amount of the positional deviation. Therefore, it is possible to move the seed wire in the direction of eliminating the positional deviation when the pulling position is assembled.

(Examples) Hereinafter, the present invention will be described with reference to exemplary drawings.

FIG. 1 is a conceptual diagram showing the first invention. In FIG.
The seed wire 1 is wound around a drum 2 having a groove (not shown), its free end side is pressed by a wire presser 3, and its tip is passed through a hole 5 formed in an upper rotation mechanism base 4. It is hung on a crucible (not shown). In the present invention, a conductive cylindrical body 7 is attached to the hole 5 via an insulator 6, and a continuity detector 8 is arranged between the cylindrical body 7 and the winding end side of the seed wire 1. The continuity detector 8 is provided with an alarm means 9 such as an alarm generator or an alarm lamp that operates at the time of conduction, but the seed wire 1 is not normally in contact with the cylindrical body 7, and therefore the current Does not flow and the alarm means 9 does not operate.

Then, for example, when the seed wire 1 is displaced during operation or when the work of weakening the tension of the seed wire 1 is performed, if there is excessive relaxation, the seed wire 1 sags and comes into contact with the cylindrical body 7. The alarm means 9 is activated.

Therefore, the operator can properly maintain the tension of the seed wire 1 and prevent accidents due to excessive tension relaxation.

2 to 5 are drawings relating to the second invention,
FIG. 2 is a plan view for explaining the principle, FIG. 3 is a front view of the same, FIG. 4 is an output display graph of a rangefinder according to rotation of the crucible, and FIG. 5 is a chart showing an output processing system of the rangefinder.

In the second invention, when a eddy current range finder is used at the lower end of the seed wire, a weight 11 made of a conductive metal is attached to the seed wire as a concentric core, and a pair of left and right weights 11 are provided. The measuring instruments 12, 12 are arranged on the upper surface of the crucible 13, and the measuring instruments 12, 12 are connected to the computing unit 14 and the display unit 15. In the embodiment, the measuring device 12 is a swirl rangefinder (0-5 mm disassembled, 0.1% F
S), and the weight 11 is made of stainless steel (for example, SS-41, 2
It is assumed to be a 0 mm cylinder. If the measuring device 12 is another type, for example, an optical type, a capacitance type, or the like, the column weight 11 need not be conductive, but it does not exceed the scope of the present invention.

Here, the crucible is rotated and the distances a and b shown in FIG. 2 and FIG. 3 are measured. In the case of the embodiment, an analog type arithmetic unit equipped with a peak holder 14a, a bottom holder 14b and a subtractor 14c. ΔC = (a−b) / 2 is calculated at 14, and this deviation amount ΔC is displayed on the display unit 15. The arithmetic unit 14 may be a digital type. According to an experiment conducted by the present inventor, it has been confirmed that in the above-described embodiment, it was possible to perform measurement with an accuracy of ± 0.01 mm in a few seconds for one rotation of the crucible. In FIGS. 2 and 3, reference numeral 16 indicates a crucible rotary core, and 17 indicates a seed wire rotary core.

(Effects of the Invention) As described above, according to the present invention, the seed wire can be accurately and reliably managed, and the CZ pulling operation can be stably performed, further improving the DF ratio. Therefore, it has advantages such as improved yield.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of the first invention, FIGS. 2 to 5 are drawings relating to the second invention, FIG. 2 is a plan view for explaining the principle, FIG. 3 is the same front view, and FIG. FIG. 5 is an output display graph of the rangefinder according to the rotation of the crucible, and FIG. 5 is a chart showing the output processing system of the rangefinder. 1 ... Seed wire, 7 ... Cylindrical body 8 ... Continuity detector, 9 ... Alarm means 11 ... Weight, 12 ... Distance meter 13 ... Crucible, 14 ... Computing unit 15 ... Display

Claims (2)

(57) [Claims] 1. A method for detecting a displacement of a seed wire when the seed wire deviates from an original position by a predetermined amount,
A seed wire is inserted into the conductive cylindrical body, and the seed wire and the cylindrical body are connected to a conduction detector equipped with a warning means. The seed wire is brought into contact with the cylindrical body to obtain a warning. A seed wire position deviation detecting device for a CZ lifting device, which is characterized in that 2. A method for detecting the positional deviation and the amount of the deviation when the seed wire deviates from the position where it should originally be, and mounting a cylindrical weight as a concentric core at a proper position of the seed wire, At least a pair of measuring instruments are arranged on the left and right sides of the weight, and the measuring instrument is configured to be connected to a calculator and a display, and the position is calculated based on the difference between the distance between the weight and the measuring instrument. A seed wire position deviation detection device for a CZ lifting device, which is characterized by detecting deviation.