JPS61295853A - Contactless rotary guiding unit for vacuum device - Google Patents

Abstract

PURPOSE:To enable accurately control of the rotation of a rotary drive unit in vacuum from the exterior by supporting a rotor in a vacuum device, and providing a stator coil outside the wall of the device and a yoke member through the wall. CONSTITUTION:A rotor 2 having many teeth 2b is supported in the same vacuum device by coupling with a rotary drive unit in the device. A stator 4 is mounted on a vacuum wall 1 oppositely to the teeth 2b of the rotor 2. The stator 4 is provided by winding a coil 5 outside the wall 1, the end of a yoke member 6 is projected in the vacuum device sealingly through the wall 1 to oppose to the teeth 2a of the rotor 2. Thus, since the rotary drive force is acted without intermediary of the wall member to the rotor 2, the rotation control can be accurately performed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is directed to applying rotational force to a vacuum process apparatus, for example, for rotating a substrate holder, moving or transporting a semiconductor wafer, or driving various movable elements within a vacuum apparatus. This invention relates to a non-contact rotary introduction device for vacuum equipment that can be used to introduce.

Conventional Technology As is generally known, the means to introduce rotation into a vacuum is to use a spiral seal, such as a magnetic fluid seal, to generate rotational force by passing a rotating shaft through a vacuum wall. The two methods are the direct introduction method, which directly introduces the rotational force into the vacuum, and the indirect introduction method, which uses a magnetentor coupling between the drive shaft and the driven shaft to indirectly introduce the rotational force into the vacuum without contact.

In the former direct introduction method, it is possible to accurately control the rotation of the rotated object (for example, control the stop position, rotation angle, etc.) by controlling the drive of the rotating shaft.

There are problems with reliability such as vacuum leakage and lifespan. Especially in recent years, as vacuum process equipment has come to be used in high vacuums and ultra-high vacuums, problems such as leaks are becoming more and more serious. The only possible method is to use bellows. However, due to its structure, bellows also have problems in two respects: lifespan and high speed rotation.

When attempting to use the device in high vacuum or ultra-high vacuum without the problems described above, the latter method, that is, a method that utilizes magnetic coupling without breaking the vacuum, has often been adopted. An example of a magnetic coupling is shown in Figure 3 of the attached drawings. ≠ As shown in the figure, place the magnet in Figure 2 on the circumference.

Contains two compling parts arranged alternately with S.

B are arranged to face each other by cutting a vacuum wall C, and by driving one of the compulsions A in the atmosphere by a stevening motor DvC, the other companding member B in the vacuum is rotationally driven. has been done. In this case, a centripetal force is exerted in the lateral direction due to the magnetic attraction effect, resulting in stable operation.

On the other hand, due to recent high integration of semiconductor devices, dust generated in vacuum process equipment for semiconductor manufacturing has become a serious problem).
A magnetically levitated non-contact rotation introduction device has been proposed that utilizes a magnetic coupling as shown in Figure 4L to enable completely contactless rotation introduction (Japanese Patent Application Laid-Open No. 40-3
422λ Publication).

As shown in Fig. 5, this device is attached to the vacuum wall E by pinching the vacuum wall member G fixed to nine vacuum flanges PK.
3. A pair of compression members H/ and H2 configured similarly to those shown in FIG. tLt are arranged facing each other.

One camp ring member H/ in the atmosphere is connected to the template/gumotae, and the other camp ring member ItH in vacuum is connected.
J is connected to a rotating body which is rotatably supported in a non-contact manner via a magnetic levitation support device vILK around a support shaft J formed integrally with the vacuum wall part ItG, and this rotating body [
, a rotating body M is attached to the rotating body M.

As shown in the figure, the magnetic levitation support device ILK has 1 magnet installed inside the rotating body and 2 magnets attached to the above-mentioned support shaft J above and below the magnet.

It consists of a magnet 3 attached to the tip of the support shaft J, and a magnet 3 attached to the rotating body at a position opposite to the magnet 3. With such an apparatus VC, it has become possible to achieve a dust-free vacuum process apparatus.

Problems to be Solved by the Invention In the above-mentioned rotation introducing device using a magnetic coupling, play inevitably occurs in the driven-side compression member with respect to the drive-side compression member. No matter how accurately the rotor is rotated, it is not possible to increase the rotation accuracy of the rotor in a vacuum, and for example, the rotor cannot be accurately stopped at a predetermined position.

Next to improve this, it is possible to improve the positioning by cutting teeth into each magnet of the coupling member or by attaching tooth-like protrusions made of magnetic material on the magnets, but Because of this, he was unable to reduce the gap, and Sei 1&[ was forced to reach his limit.

Therefore, one object of the present invention is to eliminate the drawbacks of the conventional rotation introduction device using a magnetic coupling, and to provide a vacuum system that enables precise external control of the rotation of a rotary drive body in a vacuum. We are currently installing a non-contact rotational introduction device k for equipment.

Means for Solving the Problems In order to achieve the above objects, the present invention provides a non-contact rotation introduction device for a vacuum device, which is connected to a rotationally driven body within the vacuum device, and which is connected to a rotationally driven body within the vacuum device, and which is arranged at equal intervals on the same circumference. and a rotor with a large number of teeth arranged radially.

It is attached to the vacuum equipment wall at a position opposite to this rotor,
A number of windings and portions located outside the vacuum device wall, which are sequentially energized to drive the rotor, are passed through the vacuum device wall in a sealed manner to a position opposite the teeth of the rotor within the vacuum device. The stator has a protruding yoke member.

According to another aspect of the present invention, the above device is provided with a displacement prevention device for preventing displacement of the rotor in the axial and radial directions, and the displacement prevention device prevents the rotor from being displaced in the axial and radial directions.

may consist of magnetic levitation means provided for a rotationally driven body connected to a rotor.

action In the apparatus of the present invention configured as described above.

In response to the excitation of the stator, the rotor within the vacuum device can be accurately driven at a predetermined rotation speed and rotation angle without play. When the above-mentioned other features are added to the device of the present invention, the single rotor can be accurately held at a predetermined support position without contact, and can be more accurately and stably controlled by external rotational control. It acts like a response.

EXAMPLE Hereinafter, a single winding example of the present invention will be described with reference to FIG. 72.2 of the accompanying drawings.

1st. Fig. 2 schematically shows the configuration of the main parts of the device according to the present invention, l is a vacuum wall, and a rotor 2 is disposed inside the vacuum wall, that is, on the vacuum side. As shown in , the shaft 2aVC of one rotor is supported by a suitable bearing means serving as a displacement prevention device, and a rotationally driven body (not shown) is connected to the shaft 2aVC. Further, on the lower surface of the rotor, a large number of m-coats b are formed radially arranged at equal intervals.

The stator IA is attached to the vacuum wall 1 by means of welding or the like at a position facing the rotor 1, and has a large number of windings 4I.
! and a yoke member 6 combined with each winding. As clearly shown in Figure 1, the upper surface of the yoke Ill material B has teeth 6b formed radially in correspondence with the teeth 2bVC of the rotor. It protrudes at a position adjacent to and opposite to the tooth λb of the rotor. Each winding is connected to a pulse power source (not shown) via lead wires (one of the seven is designated by 7), and is energized one after another in a predetermined order and at a predetermined energization time. Ru.

Further, from the viewpoint of improving controllability, it is preferable that the distance between the rotor and the stator be as small as possible.

In FIG. 2, reference numeral r denotes a vacuum flange, which is attached to the wall of the vacuum apparatus.
shall be used in a general sense to include the vacuum wall and vacuum holder in the illustrated device.

In the operation of the illustrated device constructed in this way, each winding of the stator Hiroshi! By exciting the rotor ljt+ in a predetermined order, the rotor can be rotated at a predetermined rotational speed or rotation angle in a predetermined rotational direction. in this case.

Since the windings, etc. that can be a source of gas are placed on the atmosphere side, there is no effect on the vacuum equipment.If necessary, a position sensor is installed to detect the rotation angle position of the rotor. te1
The excitation of the winding of the υ stator may be controlled by an output signal from the position sensor.

In addition, in the first illustrated embodiment, a fifth rotor support means is used.
A magnetic levitation support means as shown in the figure may be used, which is preferable from the viewpoint of dust-free operation. Further, although the illustrated apparatus is configured for introducing contactless rotation from the atmosphere side to the vacuum side, it can of course be used similarly in an atmosphere-atmosphere or vacuum-vacuum environment.

As described in detail, according to the present invention, the rotational drive is transmitted between the stator and the rotor without using a wall member between them, so that the conventional magnetic There is no play like in couplings, and the rotation of the rotor can be accurately controlled from the outside, and when magnetic levitation support means are used to support the rotor, the rotor is supported without contact. There is no dust generation, and stable operation can be guaranteed due to the centripetal force not only in the axial direction but also in the lateral direction.

[Brief explanation of drawings]

Fig. 1 is a schematic perspective view showing the main parts of an embodiment of the present invention, Fig. 2 is a sectional view showing the installed state of the embodiment of Fig. 1, and Fig. 3 is an example of a conventional magnetic coupling. A cross-sectional view showing , Figure V is a configuration diagram of the conciling member of Figure 4, Figure ! The figure is a sectional view showing an example of a conventional magnetic levitation type non-contact rotation introduction device. In the figure, /: vacuum wall, Koni rotor, 2b = tooth. 4t: stator, T2 winding, t: yoke member, ta: tooth. Figure 1 Figure 2 Figure 5

Claims (1)

[Scope of Claims] 1. A rotor connected to a rotationally driven body in a vacuum device and equipped with a large number of teeth radially arranged at equal intervals on the same circumference, and a position opposite to the rotor. A large number of windings located outside the vacuum apparatus wall and a part thereof are attached to the vacuum apparatus wall and are sequentially energized to drive the rotor in rotation. A non-contact rotation introduction device for a vacuum device, comprising a stator having a yoke member protruding to a position facing the teeth of the rotor. 2. A rotor connected to a rotationally driven body in a vacuum device and equipped with a large number of teeth arranged radially at equal intervals on the same circumference, and attached to the wall of the vacuum device at a position opposite to this rotor. A large number of windings located outside the wall of the vacuum device and a portion thereof are sequentially energized to rotationally drive the rotor, and are passed through the wall of the vacuum device in a sealed manner to face the teeth of the rotor inside the vacuum device. 1. A non-contact rotation introduction device for a vacuum device, comprising: a stator having a yoke member protruding to a position where the rotor is moved; and a displacement prevention device for preventing displacement of the rotor in the axial direction and the radial direction. 3. The non-contact rotation introduction for vacuum equipment according to claim 2, wherein the displacement prevention device comprises magnetic levitation means provided for the rotor or a rotationally driven body connected to the rotor. Device.