JPS6255390B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetically coupled motion introduction device that transmits motion from outside the vacuum vessel to a mechanism inside the vacuum vessel of a vacuum apparatus by magnetic coupling force.

Since this type of introducer does not have an introduction shaft sealing mechanism, it has been used for a long time especially as a rotary motion introducer for ultra-high vacuum applications. Recently, introduction machines having a linear movement function in addition to rotational movement have been put into practical use, and these have the structures shown in FIGS. 1 and 2. FIG. 1 shows a magnet having one pair of magnetic poles, and FIG. 2 shows a magnet having two pairs of magnetic poles, 2 being a permanent magnet for the external N pole, and 3 being a permanent magnet for the external S pole. Also, 4 is yoke, 5 is
1 is an internal part for one pair of magnetic poles, 6 is a partition wall, 7 is an internal part for two pairs of magnetic poles, 1 is a flange for attachment to a vacuum device, 10 is a driven object, and the arrow indicates the direction of the magnetic field. The motion transmission force of these types of introduction machines depends on the strength of the holding force of the permanent magnet, the number of poles, the clearance x between the inner and outer poles (inversely proportional to ^x2 ), and the length of the magnetic pole boundary line in the feeding direction. It will be decided. In addition, due to requirements for incorporation into vacuum equipment, operability, etc.
It is expected to have a small size yet powerful motion transmission ability.

However, in the conventional introduction machines shown in Figs. 1 and 2, the inner poles 5 and 7 of the partition wall are made of a ferromagnetic material such as magnetic stainless steel that has not been magnetized in advance, and also in the straight direction (see Fig. 1). Since there are no plural magnetic poles in the left and right directions (A and A in FIG. 2) and the length of the magnetic pole boundary line in the same direction is short, there is a drawback that a sufficient linear motion transmission force cannot be obtained.

The aim of the invention is to eliminate this drawback.

According to the present invention, in the linear rotational motion introduction machine that transmits linear and rotational motion from an external component outside a partition wall attached to a vacuum container to an internal component inside the partition wall by magnetic coupling force, the external component is first and second external permanent magnets coupled to each other via a non-magnetic spacer; a yoke for holding the first permanent magnet on the outer periphery of the first permanent magnet; and a yoke for holding the first permanent magnet; a yoke that is located on the outer periphery of the magnet and holds the second permanent magnet; The first external permanent magnet has a ring shape with different magnetic poles at both ends, and the internal permanent magnet has different magnetic poles at both ends and has an outer peripheral surface with a circular cross section between both ends. The linear motion is transmitted by the mutual magnetic coupling force of the first external permanent magnet and the internal permanent magnet, each of which has different magnetic poles extending parallel to the feeding direction, The second external permanent magnet having different magnetic poles extending perpendicularly to the feeding direction and the second external permanent magnet are arranged in opposing positions with the partition wall in between. , there is obtained a linear rotary motion introducing machine characterized in that the linear motion is introduced by magnetic coupling force with the ferromagnetic body having a shape extending in at least one direction perpendicular to the feeding direction.

Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIGS. 3 and 4 show transitional structures according to the present invention, in which the inner poles in FIGS. 1 and 2 are replaced with permanent magnets 12, respectively, and the arrows indicate the direction of the magnetic field. These structures use permanent magnets for the inner pole, which improves the rotational transmission force as well as the linear transmission force, but they have the following practical drawbacks. In other words, when the yoke 4 is gripped and a rotational force is applied to the driven object 10, if the load on the yoke 4 increases due to a change in frictional force and exceeds the coupling force between the magnetic poles, a shift occurs in the coupling part. , interference occurs between the next adjacent pole, and the repulsive force causes an unintended force (for example, a force in a straight direction) to act on the driven object 10, resulting in unnecessary force being applied. The invention also aims to eliminate this drawback.

FIG. 5 shows an embodiment of the present invention, in which part A is a rotational force transmitting part, the joint cross section has the same structure as FIG. 2B, and part B is a linear force transmitting part, and the joint cross section is is as shown in Figure 6. 8 is an external ring-shaped permanent magnet, 9 is an internal ring-shaped permanent magnet, and 11 is a non-magnetic magnetic field interference prevention spacer sandwiched between the rotational force transmission section A and the linear force transmission section B. As is clear from FIG. 6, the ring-shaped permanent magnets 8 and 9 do not have magnetic pole boundaries in the rotation direction, so
Even if the coupling part shifts during rotational motion transmission, the above-mentioned problem does not occur, and unlike the conventional magnets 8 and 9, the magnetic poles of the coupling part do not face each other with the partition wall 6 in between. , the direction of the arrow in FIG. 6 (that is, the direction of linear motion) is taken. This is to avoid problems in magnetizing the magnet, and the resulting attenuation of the coupling force can be ignored compared to the effect of improving the linear motion transmission force. Note that the rotational force transmitting section A is not limited to that shown in FIG. 5, but may have the structure shown in FIG. 1.

The gist of the present invention is to transmit motion in a linear direction by the mutual magnetic coupling force of ring-shaped permanent magnets 9 and 8, which are provided inside and outside the partition wall 6 and have magnetic poles in the feeding direction. According to the structure of the present invention, it is possible to realize a linear rotary motion introducing machine that is small in size and has an improved linear motion transmission force.

In the embodiment described above, both the inner and outer permanent magnets 9, 8 are ring-shaped permanent magnets, but the inner permanent magnet 9 is not limited to a ring-shaped one, and has different magnetic poles at both ends. Any permanent magnet may be used as long as it has an outer peripheral surface with a circular cross section. For example, the internal permanent magnet 9 may be cylindrical with different magnetic poles at both ends.

[Brief explanation of the drawing]

Figure 1A is a cross-sectional view of a conventional linear rotary motion introducer having one pair of magnetic poles, Figure 1B is a cross-sectional view of the magnetic pole coupling part of the introducer of Figure 1A, and Figure 2A is a cross-sectional view of a conventional linear rotational motion introducer having one pair of magnetic poles. A cross-sectional view of a conventional linear rotary motion introducer having a magnetic pole, FIG. 2B is a cross-sectional view of the magnetic pole coupling part of the introducer of FIG. 2A, and FIG. 4 is a cross-sectional view of the joint of the introducer in which the internal magnetic pole of the introducer shown in FIG. 2 has been replaced with a permanent magnet. FIG. The cross-sectional view of the example, Figure 6 is B in Figure 5.
FIG. 1... Flange for attachment to vacuum equipment, 2...
Permanent magnet for external N pole, 3...Permanent magnet for external S pole, 4...Yoke, 5...2-pole internal parts, 6...
...Vacuum partition, 7...Four-pole internal parts, 8...Ring-shaped external permanent magnet, 9...Ring-shaped internal permanent magnet, 10...Drived object, 11...Non-magnetic spacer, 12...Interior permanent magnet.

Claims (1)

[Claims] 1. In a linear rotational motion introduction machine that transmits linear and rotational motion from an external part outside a partition wall attached to a vacuum container to an internal part inside the partition wall by magnetic coupling force, the external part is provided with a non-magnetic spacer. first and second external permanent magnets coupled to each other via a yoke for holding the first permanent magnet on the outer periphery of the first permanent magnet; and a yoke that holds the second permanent magnet, and the internal component includes an internal permanent magnet and a ferromagnetic material that has not been previously magnetized and that are coupled to each other via a non-magnetic spacer. ,
The first external permanent magnet is ring-shaped with different magnetic poles at both ends, and the internal permanent magnet has different magnetic poles at both ends and an outer circumferential surface with a circular cross section between both ends. The directional motion is transmitted by the mutual magnetic coupling force of the first external permanent magnet and the internal permanent magnet, each of which has different magnetic poles extending parallel to the feeding direction, and the rotational directional motion is transmitted. , the second external permanent magnet having different magnetic poles extending perpendicularly to the feeding direction; A machine for introducing linear rotational motion, characterized in that the linear motion is introduced by magnetic coupling force with the ferromagnetic material having a shape extending in at least one direction.