JP2000191393A - Magnet lifting mechanism for apparatus for pulling up single crystal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnet lifting mechanism of an apparatus for pulling up a single crystal which allows good synchronous driving with the least possible maintenance. SOLUTION: The magnetic lifting mechanism of the apparatus for pulling up the single crystal, which pulls up a single crystal ingot while impressing a magnetic field thereto by the magnet 1, is constituted by providing a base 17 with a plurality of struts 3, providing the respective struts 3 with supporting members 2 for supporting the magnet 1, liftably guiding these members and lifting the respective supporting members 2 by means of ball screws 4 and ball nuts 21. The ball screws 4 are connected to one drive motor 18 by means of counter shafts and gears 24 and 25 so that the ball screws 4 are synchronously driven by the drive motor 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnet lifting mechanism of a single crystal pulling apparatus for pulling a single crystal ingot while applying a magnetic field by a magnet.

[0002]

2. Description of the Related Art Generally, a magnet elevating mechanism of a single crystal pulling apparatus has a structure in which three or four columns are arranged around a magnet, and an elevating mechanism is provided on each column to drive the magnet up and down. .

In a conventional magnet lifting mechanism, the lifting mechanism of each column is driven by an individual drive motor, and the magnets are driven by a total of three or four motors.

[0004] However, it is not easy to completely synchronize three or four drive motors, and a special control device is required for that purpose.

[0005] Further, the installation space for three or four motors and the necessity of maintenance are also disadvantageous.

[0006] On the other hand, there has been proposed a magnet lifting mechanism using only one drive motor and linking each lifting mechanism with a chain.

[0007]

However, in this type of magnet lifting / lowering mechanism, when the chain is elongated, a synchronization shift occurs. For this reason, frequent maintenance was required. In addition, the possibility of the chain being broken was not small.

Further, since the connecting chain is disposed on the common base of the lifting device, the workability when approaching the inside (at the time of maintenance) is deteriorated, and the safety may be impaired.

In addition, the magnet lifting mechanism provided with the individual drive motors may be arranged in an area where the drive motors are not affected by the magnetic field due to the magnetic field. It was difficult.

The present invention solves the above-mentioned problems of the prior art, and provides a single crystal pulling apparatus capable of performing good synchronous drive with minimum maintenance and preventing the drive motor from being affected by a magnetic field. It is intended to provide a magnet lifting mechanism.

[0011]

According to the present invention, there is provided a magnet lifting mechanism of a single crystal pulling apparatus for pulling up a single crystal ingot while applying a magnetic field by means of a magnet. A member is provided on each column and guided so that it can be raised and lowered, and each support member is configured to be raised and lowered with a ball screw and a ball nut,
A magnet lifting mechanism for a single crystal pulling apparatus, wherein a ball screw is connected to one drive motor via a counter shaft and a gear, and the ball screw is driven synchronously by the drive motor.

Another solution of the present invention relates to a radiation shield elevating mechanism of a single crystal pulling apparatus for pulling up a single crystal ingot while applying a magnetic field by a magnet.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION A magnet elevating mechanism of a single crystal pulling apparatus according to the present invention is provided with a plurality of columns on a base, and a support member for supporting a magnet is provided on each column to guide the column so that it can be raised and lowered. Each support member is configured to be moved up and down by a ball screw and a ball nut, the ball screw is connected to one drive motor via a counter shaft and a gear, and the ball screw is synchronously driven by the drive motor.

Preferably, a counter shaft is connected to one end of each ball screw via a gear, and these counter shafts are arranged parallel to each other in the base.

[0015] Preferably, another countershaft is connected to said countershaft via a gear, and these other countershafts are connected thereto on an extension of the output shaft of the drive motor.

As the gear, a bevel gear or a worm gear can be used.

Preferably, the supporting member is guided by a ball-type linear guide disposed on a support.

It is preferable that the drive motor is located far away from the magnetic field generating source, for example, in an area of 500 gauss or less which is not affected by the magnetic field.

[0019]

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

FIG. 1 is a front view showing an embodiment of a magnet lifting mechanism of a single crystal pulling apparatus according to the present invention. 2 and 3 are a side view and a top view, respectively.

The magnet lifting / lowering mechanism 30 is provided in the single crystal pulling apparatus 19. The single crystal pulling apparatus 19 is configured to form a magnetic field by the magnet 1 and pull up the single crystal ingot while applying the magnetic field to the polycrystalline melt (both not shown) in the crucible. The magnet lifting mechanism 30 is for raising and lowering the magnet 1.

The magnet lifting / lowering mechanism 30 is set on a common base 17 common to the single crystal pulling apparatus 19. The base 17 is rectangular and has a hollow inside.

On the base 17, three columns 3 are set in the vertical direction. The columns 3 are arranged at equal intervals around the magnet 1. The number of the columns 3 is not limited to three, and four or more columns may be provided.

Each column 3 is provided with a lifting mechanism 20. These elevating mechanisms 20 are synchronously driven by one drive motor 18 disposed at a corner of the common base 17. As the drive motor 18, a geared motor 18 with an electromagnetic brake can be used.

The elevating mechanism 20 includes a support portion 2 guided so as to be able to move up and down along the column 3, a ball screw 4 and a ball nut 21 for moving the support portion.

A ball-type linear guide 5 is provided on the support 3, and the support 2 is guided by the linear guide and moves up and down along the support 3. Since the ball-type linear guide 5 is used, it is possible to prevent the support portion 2 from swaying due to ascending and descending.

The ball screw 4 is rotatably supported on the upper and lower portions of the column 3 via bearings. The ball screw 4 is arranged in a vertical direction parallel to the guide direction of the linear guide 5.

The support 2 is an arm having a pad at the tip. A ball nut 21 is fixedly provided at the base of the support 2. The support part 2 includes a support 3
It is supported so as to project inward from.

The ball nut 21 is engaged with the ball screw 4. When the ball screw 4 rotates, the support 2 moves up and down along the ball screw 4 together with the ball nut 21. And the magnet 1 supported by the pad of the support part 2 also
Go up and down with this.

Each ball screw 4 is connected to the above-described geared motor 18 with an electromagnetic brake via a transmission mechanism described below.

The lower end of the ball screw 4 is connected to the gear box 7
The bevel gears (bevel gears) 24 and 25 are connected to one end of the counter shaft 8. The gear box 7 is configured to convert the axial direction by 90 degrees.
The gear box 7 and the counter shaft 8 are arranged in a hollow portion of the base 17. Three counter shafts 8
Are arranged in parallel with each other.

A counter shaft 15 is connected to the other end of the counter shaft 8 via a coupling 10 and gear boxes 11 to 13. Gear box 11-1
Inside 3, a plurality of bevel gears are arranged. In FIG. 3, the two bevel gears 22 of the right gearbox 11,
23 is shown, but the center and left gearboxes 12,
A bevel gear (not shown) for transmitting rotation to the countershaft 15 at the next stage is also arranged in the block 13.

The right gearbox 11 is provided with one input shaft and one output shaft, and both are orthogonal to each other. The left and center gearboxes 13 and 12 have one input shaft,
One output shaft coaxial with the input shaft and one output shaft orthogonal to the input shaft are provided.

The gearbox 13 is connected to the output shaft of the drive motor 18 via a coupling 16. The gear box 13 and the central gear box 12 are connected to each other via a counter shaft 15 and a coupling 14. In addition, the central and right gearboxes 12, 11
Are similarly connected. Counter shaft 15
Are arranged on an extension of the output shaft of the drive motor 18.

The gear boxes 11 to 13 and the counter shaft 15 connecting the gear boxes 11 to 13 are arranged in a line on the side surface of the base 17.

In the present embodiment, since mechanical synchronization is achieved by the above-described transmission mechanism, there is no deviation and smooth lifting and lowering is possible. Of course, no special control for synchronization is required.

Further, since there is only one drive motor 18, the maintenance time, the possibility of failure, and the running cost can be reduced.

Similarly, since only one drive motor 18 is used, space is saved, and a large maintenance area can be taken.

Further, since the transmission mechanism is constituted by the gears 22 to 25, the transmission mechanism does not extend like a chain, so that the adjustment of the transmission mechanism is unnecessary, and the maintenance time can be further reduced.

Further, the gears 22 to 25 are higher in rigidity than the chain, and the risk of breakage can be reduced.

Further, since the counter shafts 8 are pulled out from the respective elevating mechanisms 20 in the same direction inside the base and connected to each other, a large space on the base can be obtained.
In particular, the approach to the crucible driving unit becomes easy and safe, and the maintenance performance can be improved. The drive motor 18 can be arranged in a corner of the common base 17 which is not affected by the magnetic field, for example, in an area of 500 gauss or less, and malfunction of the drive motor 18 due to the influence of the magnetic field can be prevented.

The present invention is not limited to the above embodiment. For example, the drive motor may be connected to a central gearbox. Further, a configuration may be employed in which the direction of the shaft is changed using a worm gear.

[0043]

According to the magnet lifting mechanism of the single crystal pulling apparatus of the present invention, good synchronous driving can be performed with minimum maintenance.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a magnet lifting mechanism of a single crystal pulling apparatus according to the present invention.

FIG. 2 is a side view of the magnet lifting / lowering mechanism of FIG. 1;

FIG. 3 is a top view of the magnet lifting / lowering mechanism of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnet 2 Support member 3 Prop 4 Ball screw 5 Ball type linear guide 7 Bevel gear 8 Counter shaft 17 Base 18 Counter shaft 21 Ball nut 22-25 Bevel gear

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hiroo Watanabe 378 Oguni-machi, Oguni-machi, Oguni-machi, Nishiokitama-gun, Yamagata F-term in the Oguni Plant of Toshiba Ceramics Co., Ltd. 3F004 EA40 GA07 JA10 4G077 AA02 EG25 EG29 EJ02

Claims (7)

[Claims] In a magnet lifting mechanism of a single crystal pulling device for pulling up a single crystal ingot while applying a magnetic field by a magnet, a plurality of columns are provided on a base and a magnet is provided. A support member (2) for supporting the support is provided on each of the columns (3) so as to be capable of ascending and descending,
The lifting and lowering of each support member (2) is performed by a counter shaft (8, 1
5) A magnet lifting / lowering mechanism for a single crystal pulling apparatus, wherein the driving is performed by one drive motor (18) via a gear (22 to 25). 2. A structure in which each support member (2) is raised and lowered by a ball screw (4) and a ball nut (21), and the ball screw (4) is mounted on a counter shaft (8, 15) and a gear (22).
-25) to one drive motor (18),
The magnet lifting mechanism for a single crystal pulling apparatus according to claim 1, wherein the ball screw (4) is driven synchronously by its drive motor (18). 3. A counter shaft (8) is connected to one end of each ball screw (4) via a gear (7), and these counter shafts (8) are arranged parallel to each other in a base (17). The magnet lifting / lowering mechanism for a single crystal pulling apparatus according to claim 2, wherein: 4. Another countershaft (15) is connected to said countershaft (8) via gears (22, 23), said further countershaft (15) being the output shaft of a drive motor (18). The magnet lifting / lowering mechanism for a single crystal pulling apparatus according to any one of claims 1 to 3, wherein the magnet lifting / lowering mechanism is connected to an extension line of the magnet. 5. A magnet lifting mechanism for a single crystal pulling apparatus according to claim 1, wherein a bevel gear (22 to 25) or a worm gear is used as the gear (22 to 25). . 6. The single crystal according to claim 1, wherein the support member is guided by a ball-type linear guide arranged on the column. Magnet lifting mechanism for lifting equipment. 7. The single crystal according to claim 1, wherein the drive motor is arranged in a region far from the magnetic field source and unaffected by the magnetic field. Magnet lifting mechanism for lifting equipment.