JPH07108088B2 - Actuator - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive shaft arranged in a hollow cylindrical body so as to be rotatable and axially movable, and can be moved around the outer periphery of the cylindrical body in a rotational direction or an axial direction. The present invention relates to an actuator configured to be able to drive the drive shaft in the rotation direction or the axial direction from the outside in a non-contact manner by utilizing the magnetic coupling by the magnet disposed in the above.

BACKGROUND ART As is well known, in semiconductor-related industries such as integrated circuits and transistors, vacuum application equipment is used in many of the manufacturing processes. Further, the vacuum chamber requiring a high degree of vacuum state is also used in the field of manufacturing magnetic recording elements, display elements and the like, and high vacuum technology is also indispensable for vapor deposition work in a vacuum furnace and a sputtering chamber.

Vacuum application equipment used in these various technical fields and test equipment used for the development and research of vacuum utilization technology generally impair the high degree of vacuum in a vacuum container completely shielded from the outside air. It is required to operate smoothly under conditions that do not warp. Therefore, various works and samples stored in the vacuum container are linearly moved and / or moved in the container.
Alternatively, it is often necessary to rotate and move it to change its posture, and for this reason, an apparatus for driving a work or the like in a vacuum container from the outside without contact is required. In addition to the vacuum application equipment, it can also be used as a storage container for substances such as radioactive liquids and toxic liquids that need to be prevented from leaking to the outside, or as a drive mechanism for valves used in the fluid pipeline system. There is a demand for an actuator that can be operated in a non-contact manner from the outside.

In order to meet the demands of the industrial world, the applicant of the present invention utilizes magnetic coupling between a ferromagnetic core arranged inside a hollow cylinder and a magnet arranged corresponding to the outer circumference of the cylinder. The non-contact drive of the ferromagnetic core is performed, and the drive shaft inserted and fixed in the ferromagnetic core is linearly moved back and forth along the central axis thereof, and rotationally moved about the axis, respectively. As an apparatus for obtaining the above, an actuator having a structure as shown in FIG. 1 was newly developed.

This actuator is provided in a vacuum device 10 such as a sputtering chamber, and has a drive shaft 16 with a hand 14 attached to the tip thereof.
Is driven by non-contact by magnetic coupling, and the work 12 placed in the vacuum chamber 10 is moved. That is, a hollow cylindrical body 18 made of a non-magnetic material extends horizontally outside the vacuum device 10, and the hollow portion of the hollow cylindrical body 18 communicates with the vacuum chamber and is maintained in a vacuum atmosphere. A drive shaft 16 is rotatably and axially movably inserted into the hollow cylindrical body 18, and the drive shaft 16 has two ferromagnetic cores 20 divided into a thrust generating portion A and a rotating force generating portion B. Twenty is fixed. Further, on the outer circumference of the hollow cylindrical body 18, two magnetic structures 2 which are also in charge of the thrust generating portion A and the rotating force generating portion B are provided.
2, 22 are arranged so as to be rotatable and axially movable. Then, by moving the magnetic structure 22 along the outer surface of the cylindrical body 18, the ferromagnetic core 20 is moved to the magnetic structure 22.
It can be moved in a non-contact manner so as to be rotatable and / or axially movable under the action of magnetic coupling with.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention This actuator is highly evaluated in that it can satisfactorily drive various works in a vacuum chamber from the outside under atmospheric pressure without contact, but as described above, the ferromagnetic core and the magnetic core are used. Since the structure has a unique structure in which the thrust generating portion A and the rotating force generating portion B are separated, there is a drawback that the structure becomes complicated and the manufacturing cost increases. That is, the mechanism for generating the thrust force and the mechanism for generating the rotational force have different configurations, and the thrust force generation and the rotational force generation are not provided by one mechanism.

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned drawbacks inherent in the actuator according to the prior art, and has been proposed in order to solve this problem. SUMMARY OF THE INVENTION It is an object of the present invention to provide an actuator having a simplified structure in which a ferromagnetic core magnetically coupled with a magnetic core can be rotated or axially moved in a non-contact manner by rotating or axially moving the same. .

Means for Solving the Problems In order to achieve the above-mentioned object, an actuator according to the present invention comprises a drive shaft rotatably and axially movable inside a hollow cylindrical body made of a non-magnetic material, and an axial direction of the drive shaft. A plurality of ferromagnetic cores, which are inserted and fixed with a required space held between them, a cylindrical manipulator disposed on the outer periphery of the hollow cylinder so as to be rotatable and axially movable, and a cylindrical manipulator In an actuator comprising an annular yoke made of a ferromagnetic material and provided at a circumference with a required interval in the axial direction, and a magnet arranged inside the annular yoke, in an outer circumferential direction of the ferromagnetic core, A plurality of ridges are formed at a required center angle, and a plurality of magnets are arranged at a required center angle in the inner circumferential direction of the annular yoke. To the respective annular yokes The respective magnets in the magnets are magnetically coupled to each other through the hollow cylindrical body, and the magnetism of each magnet arranged in the annular yoke corresponds to the polarity of the magnets arranged in the axially adjacent annular yokes. It is characterized in that they are arranged so that they have different polarities.

Embodiments Next, an actuator according to the present invention will be described below with reference to the accompanying drawings with reference to a preferred embodiment. FIG. 2 is a longitudinal sectional view showing the actuator of the present invention,
Since it is a portion corresponding to a portion surrounded by a circle C in FIG. 1, the same reference numerals are given to the same constituent members as those already described.

The hollow cylindrical body 18 described with reference to FIG. 1 is, for example, 18-8SU.
A non-magnetic material such as S (stainless steel) is used as a material, and one open end of the material is connected and communicated with the vacuum device 10.
The other closed end extends horizontally outside the device.
A magnet, which will be described later, is provided on the outer periphery of the hollow cylindrical body 18 with the hollow cylindrical body 18 separated.
30 is movably arranged, and inside the hollow cylindrical body 18, a ferromagnetic core 20 inserted and fixed to the drive shaft 16 is movably arranged.

That is, a ferromagnetic core that is axially inserted and fixed to the drive shaft 16.
Reference numeral 20 denotes an axially long core made of a ferromagnetic material such as 13Cr electromagnetic stainless steel, and its cross section has a shape of, for example, a 6-pole motor rotor as shown in FIG. There is. A plurality of ferromagnetic cores 20 (two or more, three in this embodiment) are arranged and fixed in the axial direction of the drive shaft 16 at required intervals via spacers 24 made of a non-magnetic material. . Since the drive shaft 16 is supported so as to be able to rotate in the circumferential direction and move in the axial direction inside the hollow cylindrical body 18, the ferromagnetic core 20 is also a hollow cylindrical body as a natural consequence.
It is rotatable and axially movable within 18.

Next, on the outer circumference of the hollow cylindrical body 18, sliders 26, 2 such as slide metal that allow movement in the rotational direction and the axial direction are provided.
A cylindrical operation body 27 is disposed coaxially with the cylindrical body 18 via 6 and is configured so as to be capable of rotational movement and axial movement together with the sliders 26, 26. This cylindrical manipulator 27
A plurality of annular yokes 28 made of a ferromagnetic material such as electromagnetic soft iron (S20C) are arranged in the axial direction of the inner peripheral surface at a predetermined interval via a spacer 32 made of a non-magnetic material. (3 in the illustrated embodiment). As shown in FIG. 3, a plurality of (n) rare earth magnets 30a to 30n are arranged adjacent to each other on the inner peripheral surface of each annular yoke 28 at a predetermined center angle in the radial direction.

In this case, the respective rare earth magnets 30 arranged on the annular yoke 28 have mutually different polarities with respect to the rare earth magnets 30 correspondingly arranged on the annular yoke 28 adjacent in the axial direction of the cylindrical operating body 27. Arrange so that That is, as shown in FIG. 2, if the leftmost rare earth magnet 30 has an N pole, the polarities of the corresponding rare earth magnets 30 adjacent to each other will be S pole, N pole ... Arrange.

The plurality of ferromagnetic cores 20 inserted and fixed in the axial direction of the drive shaft 16 at a required interval, the plurality of magnets 30 arranged at a required interval on the inner peripheral surface of each annular yoke 28, Hollow cylinder 18
Corresponding positional relationships are set so as to be magnetically coupled via. At this time, the size of the annular gap of equal width formed between the inner surface of the rare earth magnet 30 and the outer peripheral surface of the hollow cylindrical body 18 is preferably selected to be 0.3 mm or 1.0 mm, for example.
Further, the material of the ferromagnetic core may be commonly used iron or its alloy, especially electromagnetic mild steel or 13Cr electromagnetic stainless, etc., and the spacer is made of non-magnetic metal or alloy such as stainless steel or brass. It Further, the magnet material is also arbitrary and can be selected from alnico, rare earth alloys and other ferromagnetic alloys, or various ferrites.

Operation of the Invention Next, the operation of the actuator according to the present invention configured as described above will be described. In the structure of the present invention, as is clear from FIG. 3, a plurality of protrusions 20a formed in the axial direction of the ferromagnetic core 20 and a plurality of rare earth magnets 30 similarly arranged in the axial direction are provided. Due to the close correspondence, high-density magnetic flux can be focused evenly in the axial and cylindrical directions. Therefore, by rotating or axially moving the cylindrical operating body 27 in which the rare earth magnet 30 is provided via the annular yoke 28, the ferromagnetic core 20 magnetically coupled to the cylindrical operating body 27 is moved. And the drive shaft 16 can be rotationally or axially moved well.

In this case, as shown in FIG. 2, the polarities of the respective rare earth magnets 30 arranged on the annular yoke 28 are arranged so that the polarities of the rare earth magnets 30 corresponding to the adjacent annular yokes 28 are alternately different. Therefore, the thrust force during linear movement is significantly increased for the following reasons. As shown in FIG. 4, assuming that the rare earth magnets 30a, 30b and 30c are arranged in the order of N pole, S pole and N pole, the corresponding ferromagnetic cores 20a, 20b and 20c are It is excited by the S pole, N pole, and S pole via the hollow cylindrical body 18. When the cylindrical operating body 27 is slid to the right in this state, the rare-earth magnet 30a moves to the corresponding ferromagnetic core 2 excited by the S pole.
0a is strongly magnetically attracted to generate thrust in the moving direction of the operating body 27 (arrow AT). In addition, this N pole rare earth magnet 30a
Causes a repulsive force (arrow RP) to repel a ferromagnetic core 20b that is adjacent to this via a hollow cylinder 18 and is excited by the N pole, and the repulsive force (arrow RP) to the ferromagnetic core 20b. Convert as thrust. This relationship is related to the S pole rare earth magnet 30b.
And the corresponding ferromagnetic core 20b and the adjacent ferromagnetic core 20c via the hollow cylindrical body 18 are exactly the same, and therefore, a thrust force larger than that in the case of the homopolar arrangement can be obtained. Is.

EFFECTS OF THE INVENTION As described in detail above, according to the actuator of the present invention, a plurality of drive shafts rotatably and axially movably disposed inside a hollow cylindrical body are fixed and separated by a plurality of ferromagnetic cores. And magnetically coupled with a plurality of magnets axially spaced apart corresponding to the outer circumference of the hollow cylinder, and by moving the magnets on the outer circumference of the hollow cylinder, the magnet is integrated with the ferromagnetic core. The drive shaft can be driven in the rotational direction or the axial direction in a non-contact manner, and since the structure is simplified, the manufacturing cost can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic structural view of an example in which an actuator is provided in a vacuum device, FIG. 2 is a vertical sectional view showing an example of an actuator according to the present invention, and FIG. 3 is a lateral sectional view taken along the line aa in FIG. Fourth
The figure is a longitudinal sectional view schematically showing the reason why the thrust is increased when the rare earth magnets are arranged with different poles in the axial direction. 16 …… Drive shaft, 18 …… Hollow cylinder 20 …… Ferromagnetic core, 24 …… Spacer 26 …… Slider, 27 …… Cylinder operating body 28 …… Cylinder yoke, 30 …… Rare earth magnet

Claims (1)

[Claims] 1. A drive shaft (16) rotatably and axially movable inside a hollow cylindrical body (18) made of a non-magnetic material.
And a plurality of ferromagnetic cores (20) inserted and fixed at a predetermined interval in the axial direction of the drive shaft (16) and rotatable and axially movable around the outer circumference of the hollow cylindrical body (18). A cylindrical manipulating body (27) disposed on the inner surface of the cylindrical manipulating body, and an annular yoke (28) made of a ferromagnetic material and provided on the inner circumference of the cylindrical manipulating body (27) at a predetermined axial distance. An actuator including a magnet (30) arranged inside an annular yoke (28), wherein a plurality of protrusions (20a) are formed at a required central angle in the outer circumferential direction of the ferromagnetic core (20). In addition, a plurality of magnets (30) are arranged at a required central angle in the inner circumferential direction of the annular yoke (28), and the ridges (20) of the plurality of ferromagnetic cores (20) are arranged.
a) the magnets (3) in the respective annular yokes (28).
0) correspondingly magnetically coupled to each other through the hollow cylindrical body (18), and the polarities of the respective magnets (30) arranged in the annular yoke (28) are different from each other in the axially adjacent annular yokes (28). An actuator characterized in that the magnets (30) arranged correspondingly are arranged so as to have mutually different polarities.