JPH08183631A - Pulling-up device for synthetic quartz and th like - Google Patents

Abstract

PURPOSE: To provide a pulling-up device with a function capable of automatically correcting the inclination of a perpendicularly hung shaft. CONSTITUTION: This pulling-up device is provided with an inclination correcting mechanism 5 between a moving table 3 and a rotational driving mechanism 2. This inclination correcting mechanism 5 has an upper plate and a lower plate and pivotally supports this upper plate freely tiltably relative to the lower plate. The other end of the upper plate is vertically drivably supported by a supporting mechanism from the rear surface side. An inclination detecting sensor is mounted at the upper plate. This inclination detecting sensor and the driving section of a bearing mechanism are respectively electrically connected to a control section. Further, the inclination correcting mechanism is installed by superposing the two mechanisms and is so constituted that the pivotal axes of the respective mechanisms shift from each other by 90 deg. in plane view. The inclination generated at a moving table of the pulling up column is corrected by two units of the inclination correcting mechanisms 5a, 5b, by which the surface of the moving table is held horizontally.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for pulling synthetic quartz or the like, and more particularly to a device for automatically raising the inclination of a vertically suspended shaft when forming synthetic quartz or the like. .

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 5, synthetic quartz, which is used as a material for optical fibers, has a long shaft 101 held vertically, and synthetic quartz a is attached to the lower end of the long shaft 101. It is formed by inserting it inside b and rotating it. The above-mentioned glass chamber b is provided with a burner c for burning a gas containing a quartz raw material without being jetted, and by heating the lower end portion of the synthetic quartz a inserted into the chamber b by the burner c, Molten quartz is adhered, and the columnar synthetic quartz a is formed by gradually melting and growing the lower end of the synthetic quartz a. The pulling apparatus described above is also used for manufacturing single crystal silicon.

[0003]

Since the synthetic quartz column a formed as described above gradually becomes longer in the downward direction along with the melt growth, the shaft 101 rotating in accordance with the growth is pulled up, It is necessary to always place the lower end surface of the synthetic quartz column a on the extension line of the burner c. Conventionally, as described above, the pulling device 100 configured to pull up while rotating the shaft 101 includes a rotary drive mechanism 102 that holds the upper end of the shaft 101 and drives it to rotate in a state of being vertically suspended and the mechanism. Supporting vertical movement mechanism 10
3 and 3. The rotary drive mechanism 102 is installed horizontally on the moving table 104 of the vertical moving mechanism 103, and is vertically moved along a vertical guide 105 while holding the moving table 104 horizontally,
The shaft 101 suspended vertically is gradually pulled up.

By the way, the pulling device 100 described above.
Suspends the shaft 101 vertically.
It is constructed so that the synthetic quartz column a attached to the lower end can be rotationally driven as accurately as possible. However, in the lifting device 100 as described above, the guide 1 of the vertical moving mechanism 103 is used when the moving table 104 having the rotation driving mechanism 102 is vertically moved by the vertical moving mechanism 103.
Due to the influence of the machining accuracy of 05 and rigidity deformation, the movable table 104 to be held horizontally is slightly inclined. As a result, the rotary drive mechanism 103 installed on the moving table 104 is tilted, and the rotary drive mechanism 103 is further tilted.
As a result, the vertically suspended shaft 101 is inclined.

Although the shaft 101 has a slight inclination as described above, the error is amplified at the lower end of the shaft 101 because the entire length of the shaft 101 is long. As a result, the distance d between the axis of the synthetic quartz column a attached to the lower end of the shaft 101 and the tip of the burner c changes, which adversely affects the melt growth of the synthetic quartz column a. The distance d between the synthetic quartz a and the tip of the gas burner c is an important factor in forming a good quality synthetic quartz column a, and it is important to keep the distance d constant at all times.

An object of the present invention is to provide a conventional pulling device as described above with a function of automatically correcting the inclination of a vertically suspended shaft, and a synthetic quartz column and a burner caused by the inclination of the shaft. It is to prevent the change in the distance between and.

[0007]

In order to achieve the above-mentioned object, the present invention grasps the upper end of a shaft vertically suspending synthetic quartz or the like that melts and grows, and enables the shaft to be rotatably driven. It is equipped with a rotation drive mechanism that supports it, and this rotation drive mechanism is installed on a moving table that is held horizontally.
In a pulling device for synthetic quartz or the like, which supports the moving table so that it can be vertically moved up and down by a vertical moving mechanism, a tilt correcting mechanism is provided between the moving table and a rotation driving mechanism, and the tilt correcting mechanism is a horizontal plane. The upper plate and the lower plate constituting the above are provided, and a pivot is horizontally supported on the lower plate, and one end of the upper plate is pivotally supported by the pivot to support the upper plate in a tiltable manner. A support mechanism provided on the plate supports the other end of the upper plate so that it can be vertically driven from the lower surface side, an inclination detection sensor is attached to the upper plate, and the inclination detection sensor and the drive unit of the support mechanism serve as a control unit. The control unit calculates the tilt amount of the upper plate and its correction amount based on the signal input from the tilt detection sensor, and directs it to the drive unit of the support means based on the calculation result. Correction control to output drive control signal The stage is provided, and, the inclination correction mechanism 2 between the moving table and the rotary drive mechanism
It is constructed by stacking the machines so that the pivot axes of the respective mechanisms are displaced by 90 ° in plan view.

[0008]

According to the above means, the shaft having the synthetic quartz attached to the lower end is vertically hung by the upper end being held by the rotary drive mechanism. The rotary drive mechanism is installed on a moving table that hangs the shaft rotatably and holds it horizontally. Further, the horizontally held moving table is vertically moved up and down by the vertical moving mechanism, and the shaft suspended by the rotary drive mechanism is vertically moved up and down along the axis thereof.

Two tilt correction mechanisms are superposed on each other between the movable table and the rotary drive mechanism. Each of the tilt correction mechanisms includes an upper plate and a lower plate that form a horizontal plane. The pivot is supported horizontally on the lower plate,
One end of the upper plate is pivotally supported by this pivot, and the upper plate is supported so as to tilt. On the other hand, a supporting mechanism is provided on the lower plate, and the other end portion of the upper plate is supported by the supporting mechanism so as to be vertically movable from the lower surface side so that the upper plate can be tilted with respect to the horizontal plane. I support you. Further, an inclination detection sensor is attached to the upper plate, and the inclination detection sensor and the drive portion of the support mechanism are electrically connected to the control portion. The control unit calculates the tilt amount of the upper plate and the correction amount thereof based on the signal input from the tilt detection sensor.

Therefore, when the moving table is tilted during the vertical movement by the vertical moving mechanism, the shaft is tilted together with the rotary drive mechanism installed horizontally on the table. At this time, the tilt detection sensor of the tilt correction mechanism installed on the moving table outputs a signal according to the tilt amount to the control unit. The control unit calculates the inclination amount and the correction amount of the upper plate based on the above signals, and outputs a drive control signal for performing the correction to the drive unit of the supporting means based on the calculation result. The support means receives the above signal and drives up or down, thereby tilting the upper plate in a direction to cancel the tilt generated and keeping the rotary drive mechanism horizontal, and the shaft suspended by the mechanism is vertical. To maintain.

The tilt correction mechanism of the two machines constructed as described above is provided between the movable table and the rotary drive mechanism.
They are installed so that the machines overlap each other, and the pivot axes of the respective mechanisms are configured to be offset by 90 ° in plan view. For example, when the tilt directions of the both tilt correction mechanisms described above are applied to the X and Y directions in a plan view, the shaft vertically suspended by the tilt operation of one tilt correction mechanism tilts in the X direction and the other tilt. The shaft is tilted in the Y direction by the tilting operation of the correction mechanism. Therefore, the both tilt correction mechanisms having the above-described functions individually detect the tilts in the X and Y directions generated on the moving table, and independently perform the tilt corrections in the X and Y directions, respectively. Keep horizontal.

[0012]

An embodiment of the present invention will be described below with reference to the drawings. The pulling device shown in FIG. 1 gradually pulls up a synthetic quartz column a formed inside a glass chamber b while rotating it.

The chamber b is provided with an opening b1 in its upper part, and a synthetic quartz column a is inserted therein. The synthetic quartz column a is attached to the lower end of the shaft 1 and is vertically inserted into the chamber b together with the shaft 1 through the opening b1. Also,
A burner c is provided on the peripheral wall of the chamber b, and combustion gas is injected from the burner c together with the raw material of quartz to heat the lower end of the synthetic quartz column a. The distance between the axis of the synthetic quartz column a and the tip of the burner c is kept at a predetermined distance d in order to melt and grow the synthetic quartz a in a good state.

As described above, the pulling device includes a rotary drive mechanism 2 for holding the upper end of the shaft 1 for vertically suspending the synthetic quartz column a, a movable table 3 for horizontally installing the mechanism 2, and the movement. The table 3 is composed of a vertical moving mechanism 4 for vertically moving the table 3 and an inclination correcting mechanism 5 interposed between the moving table 3 and the rotary driving mechanism 2.
The rotary drive mechanism 2 includes a chuck 21, and the chuck 2
1 holds the upper end of the shaft 1 and vertically suspends the shaft 1 itself. The chuck 21 is rotationally driven by a driving mechanism (not shown) provided inside the mechanism to rotate the gripped shaft 1 at a predetermined speed. The rotation drive mechanism 2 is provided with a vertical movement mechanism 4 via an inclination correction mechanism 5 described later.
It is installed horizontally on the moving table 3 of FIG.

The movable table 3 is supported in a cantilever state by slidably engaging one end of the movable table 3 with the guide 41 of the vertical movement mechanism 4, and the upper surface of the table extending from the engaging portion 31 is fixed. The table is maintained horizontally, and the tilt correction mechanism 5 and the rotation drive mechanism 2 are supported on the upper surface of the table.
The moving table 3 includes a vertical moving mechanism 4 that extends vertically.
By sliding along the guide 41 of the table, the table is guided to move vertically while keeping the upper surface of the table horizontal, and the drive mechanism (not shown) provided in the vertical moving mechanism 4 is engaged at one end of the table. By being connected to the portion 31, it is supported so as to be vertically movable. The vertical movement mechanism 4 includes a chamber b.
As the synthetic quartz column a inserted therein melts and grows downward, the moving table 3 is gradually raised so that the lower end of the synthetic quartz column a is always maintained on the extension line of the burner c.

The tilt correcting mechanism 5 is installed on the moving table 3 and supports the rotary drive mechanism 2 from below to hold it horizontally. When the moving table 3 tilts, the tilt is corrected. It has a function of correcting and holding the rotary drive mechanism 2 horizontally, and thereby maintains the shaft 1 suspended by the rotary drive mechanism 2 vertically. Tilt correction mechanism 5
Is constructed by stacking two correction mechanisms 5a and 5b having exactly the same structure, and these two correction mechanisms 5a and 5b separately correct tilts in both the X and Y directions in plan view. I am doing it.

2 and 3 show the two correction mechanisms 5a and 5b constituting the tilt correction mechanism 5. As shown in FIG. Both mechanisms 5a,
Since 5b is configured in exactly the same manner, the description of the configuration will be given mainly on the correction mechanism 5a installed on the upper side. The correction mechanism 5a includes an upper plate 51 and a lower plate 5 on which the rotary drive mechanism 2 is placed.
Equipped with 2. A pivotal support member 53 is provided along one end of the lower surface of the upper plate 52, and a pivot shaft 53a horizontally projected from both ends of the pivotal support member 53 is erected at one end of the upper surface of the lower plate 52 at intervals. The two bearing pieces 53c are axially attached. As a result, the upper plate 52 has one end portion
Is pivotally supported with respect to the upper surface of the upper plate 51, and is supported so that the other end of the upper plate 51 tilts about the pivot 53. The inclination direction of the upper plate 52 corresponds to the X direction in plan view.

On the other end of the upper surface of the lower plate 52, a rotary shaft 55c is horizontally laid horizontally, one end of which is connected to the reduction gear box 55a, and the other end is supported by a bearing piece 55b. It is axially supported in a form parallel to the pivot member 53.
An eccentric cam 54 is fixedly attached to the middle portion of the rotating shaft, the lower surface of the upper plate 51 is brought into contact with the cam peripheral surface, and the other end of the upper plate 51 is supported by the eccentric cam 54 from below. There is. The upper plate 51 on which the rotary drive mechanism 2 is installed is configured so that the eccentric cam 54 maintains horizontal at the neutral position. When the rotating shaft 55c is rotated, the eccentric cam 54 is rotated and the position of the highest part of the peripheral surface of the cam 54 is changed, and the other end of the upper plate 51 is moved up and down. As a result, the upper plate 51 is inclined in the X direction with reference to the horizontal. The spring 56 provided near the bearing member 55b includes the upper plate 51 and the lower plate 52.
And the lower surface of the upper plate 51 is always brought into contact with the peripheral surface of the eccentric cam 54 by this biasing force.

A drive motor 57 including a stepping motor or the like is mounted and supported on the reduction gear box 55a bearing one end of the rotary shaft 55c. The output shaft of the drive motor 57 is connected to a reduction mechanism housed in the reduction gear box 55a, and is connected to the rotary shaft 55c via the reduction mechanism. The drive motor 57 has a rotary shaft 5
The eccentric cam 54 provided in 5c is rotated by a predetermined angle in a predetermined rotation direction, and is electrically connected to a computer serving as the control unit 60 (FIG. 2). An inclination detection sensor 58 is provided on the upper surface of the upper plate 51. The inclination detection sensor 58 quantitatively detects the inclination of the upper plate 51, is configured by using a laser interferometer, and is electrically connected to the control unit 60 like the drive motor 57. . A servo accelerometer or a gyro can be used as the tilt detection sensor 58.

The control unit 60 is composed of a personal computer, a microcomputer or the like, and is equipped with a correction control means (not shown) having a function of detecting the amount of tilt and a correction function thereof. The correction control means (not shown) calculates the amount of tilt generated in the upper plate 51 based on the electric signal input from the tilt detection sensor 58, and corrects the tilt to correct the upper plate 51.
The amount of rotation of the cam 54 and the drive motor 57 required for returning the horizontal direction is calculated. Further, the correction control means outputs a drive control signal for driving to a rotation position required for correction to the drive motor 57 based on the above calculation result.

The correction mechanism 5b provided below the correction mechanism 5a is constructed in exactly the same manner as the correction mechanism 5a, but the pivot 53a of the correction mechanism 5b is 90 degrees with respect to the pivot 5a of the correction mechanism 5a in a plan view. It is structured so that it can be shifted. That is, the correction mechanism 5b tilts in the Y direction in plan view. The correction mechanism 5b is the upper correction mechanism 5b.
The lower plate 52 of a is also used as the upper plate, and the upper plate 52 and the lower plate 5
2'are paired to simplify the structure. However, the upper plate and the lower plate may be configured such that each two correction mechanisms are provided, and these correction mechanisms may be superposed.

The inclination detection sensor 58 and the drive motor 57 included in the correction mechanism 5b are also electrically connected to the control unit 60, like the correction mechanism 5a.
Therefore, the control unit 60 individually inputs the information of the tilt amounts in the X and Y directions from the tilt detection sensors 58 of the correction mechanisms 5a and 5b, respectively, and repeats the calculation, and the respective correction mechanisms 5a and 5b.
A drive control signal is output to the drive motor 57 of b to individually correct the tilts in the X and Y directions (FIGS. 3 and 4).

Next, the operation of the lifting device constructed as described above will be described. The pulling device described above rotates the synthetic quartz column a adhering to the lower end of the shaft 1 at a predetermined rotation speed by rotationally driving the chuck 21 of the rotary drive device 2. Synthetic quartz column a rotating inside the chamber b
The lower end of is heated by a burner c that ejects combustion gas containing quartz raw material, and gradually melts and grows downward. The pulling device moves the moving table 3 little by little in accordance with the melt growth of the synthetic quartz column a, so that the lower end surface of the synthetic quartz column a is always positioned on the extension line of the burner c, and the flame of the burner c is It is adapted to be applied to an appropriate position on the lower end surface of the rotating synthetic quartz column a.

During the vertical movement by the vertical movement mechanism 4, when the movement table 3 which should be horizontal is inclined due to the influence of the processing accuracy of the guide 41, etc.
The tilt correction mechanism 5 and the rotation drive mechanism 2 installed horizontally with respect to the top tilt, and thus the shaft 1 suspended vertically also tilts. When the correction mechanisms 5a and 5b are tilted together with the moving table 3, the tilt detection sensors 57 provided therein detect tilts in the X and Y directions, and individually output signals associated with the tilt amounts to the control unit 60.

For example, in the case of the upper correction mechanism 5a, the tilt amount in the X direction due to the tilt of the moving table 3 is output to the control unit 60. Correction control means (not shown) of the control unit 60
Is the amount of rotation of the drive motor 57 required to calculate the actual tilt amount of the moving table 3 in the X direction based on the signal information input from the tilt detection sensor 58 and correct the tilt to return it to the horizontal direction. Is calculated, and a drive control signal for obtaining a rotation angle required for correction is output to the drive motor 57 of the correction mechanism 5a. Thereby, the upper tilting mechanism 5a
Drive motor 57 rotates the eccentric cam 54 to move the upper plate 51.
Is tilted in a direction opposite to the tilt in the X direction generated on the moving table 3 to keep the upper plate 51 horizontal.

As described above, the upper correction mechanism 5a is
The tilt in the X direction generated on the moving table 3 is detected and horizontally corrected, and at the same time, the lower correction mechanism 5a also detects the tilt in the Y direction generated on the moving table 3 to correct the correction mechanism 5a. A tilt correction function similar to the above is used to correct the tilt of the moving table 3 in the Y direction and correct it horizontally. That is, even when the moving table 3 tilts in the ascending process, the tilt generated in the moving table 3 is completely corrected by the combination of the tilt corrections in the X and Y directions performed by both correction mechanisms 5a and 5b, and The correction mechanism 5a is kept horizontal on the upper plate 51. According to the tilt correction, the rotation drive mechanism 2 installed on the tilt correction mechanism 5 is maintained horizontally, and the shaft 1 suspended by the rotation drive mechanism 2 is held.
Is always kept vertical. As a result, the distance d between the axis of the synthetic quartz column a at the lower end of the shaft 1 and the tip of the burner c.
Is kept constant, and the melt growth performed by heating the burner c proceeds in a good state.

Further, as described above, both correction mechanisms 5a, 5
b and the control unit 60 to detect the inclination and the upper plate 5
The tilt correction control of No. 1 is repeatedly performed in the ascending moving column of the moving table 3, whereby the tilt generated in the moving table 3 is quickly corrected in the initial movement stage. Although the eccentric cam 54 is used as the support mechanism of the upper plate 51 in the above-described embodiment, the support mechanism is not limited to the eccentric cam, and the upper plate can be supported so as to be vertically movable. It may be of any type.

[0028]

Since the present invention is configured as described above, in the process of pulling up the shaft by the vertical movement of the moving table, the moving table and the shaft are affected by the working accuracy and rigidity of the vertical moving mechanism. Even if there is a tilt, the tilt can be detected and corrected immediately by both tilt correction mechanisms. Therefore, the rotationally driven shaft is always kept vertical by the correction function of the inclination correction mechanism, the distance between the axis of the synthetic quartz column adhering to the lower end of the shaft and the tip of the burner is always constant, and the melt growth of the synthetic quartz column etc. Can be performed in good condition.

[Brief description of drawings]

FIG. 1 is a side view showing a lifting device embodying the present invention.

FIG. 2 is a plan view showing an inclination correction mechanism of the pulling device.

FIG. 3 is a front view of the tilt correction mechanism.

FIG. 4 is a side view of the tilt correction mechanism.

FIG. 5 is a front view showing a conventional lifting device.

[Explanation of symbols]

 a ... Synthetic quartz column 1 ... Shaft 2 ... Rotation drive mechanism 3 ... Moving table 4 ... Vertical movement mechanism 5 ... Inclination correction mechanism 5a, 5b ... Correction mechanism

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kunihiro Miyashita 2-9 Kandanishikicho, Chiyoda-ku, Tokyo Shin-Etsu Engineering Co., Ltd. (72) Ichiro Ishizaka 2-9-Kandanishiki-cho, Chiyoda-ku, Tokyo Shinetsu Engineering Within the corporation

Claims (1)

[Claims] 1. A rotary drive mechanism for holding the upper end of a shaft vertically suspending melt-grown synthetic quartz or the like and rotatably supporting the shaft, and holding the rotary drive mechanism horizontally. In a pulling device such as synthetic quartz, which is installed on a moving table and is supported by a vertical moving mechanism so as to be vertically ascendable and vertically descendable, an inclination correcting mechanism is provided between the moving table and the rotation driving mechanism. The inclination correction mechanism is provided with an upper plate and a lower plate that form a horizontal plane, and the pivot is horizontally supported on the lower plate.
One end of the upper plate is pivotally supported by this pivot to support the upper plate in a tiltable manner, and the other end of the upper plate is supported by the supporting mechanism provided on the lower plate so as to be vertically movable from the lower surface side. An inclination detection sensor is attached to the upper plate, and the inclination detection sensor and the drive unit of the support mechanism are electrically connected to the control unit respectively, and the control unit controls the upper plate based on a signal input from the inclination detection sensor. Is provided with correction control means for calculating a tilt amount and its correction amount and outputting a drive control signal to the drive part of the support means based on the calculation result, and the tilt correction mechanism is provided with a moving table and a rotary drive. A pulling device for synthetic quartz or the like, in which two machines are installed in superposition with each other and the pivot axes of the respective mechanisms are displaced by 90 ° in plan view.