JPS60222618A - Magnet bearing device - Google Patents

Abstract

PURPOSE:To simply prevent a plurality of control magnets from mutually interfering at a low price in the capationed device wherein said magnets are respectively arranged in the X and Y directions keeping a proper gap against a rotary shaft by disposing the same polarity of the magnets in an adjoining relation. CONSTITUTION:The captioned device has a plurality of control magnets 2, 3 disposed in an adjoining relation, which magnets are arranged keeping a proper gap against a rotary shaft 1. In addition, a magnetic flux generted from an arbitrary magnet of for example 2 is modulated by a control current from a control circuit 4. In this instance, the respective magnets 2, 3 are arranged such that ones having the same pole, for example, an N pole are adjacent to each other. Repective magnetic fluxes phi21, phi22 from the respective magnets 2, 3 are adapted to produce repulsion force whereby the respective magnets 2, 3 are prevented from mutually interfering. Hereby, mutual interference between the respective magnets 2, 3 can be simply prevented at a low price without use of a compensation circuit while controlability of the device can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a magnetic bearing device including a plurality of control magnets.

[Background of the invention]

As shown in FIGS. 2 and 3, a conventional magnetic bearing device of this kind has a plurality of control magnets (in the figure, a pair of electromagnets or electromagnets) 2 and 3 connected to a rotating shaft 1 in the X direction and the Y direction, respectively. The magnets 2 and 3 are arranged oppositely with a gap maintained, and the magnets 2 and 3 are
Different magnetic poles, for example, the north pole of magnet 2 and the south pole of magnet 3, are arranged adjacent to each other, and a control circuit 4 is attached to magnet 2.

In such a magnetic bearing device, if there is no interference between the magnets 2 and 3, each magnetic flux φ, 1. Since φ is unique as shown in FIG. 2, each magnetic flux φ21. φ.

The forces exerted on the rotating shaft 1 are completely independent, so they do not affect each other.

However, when magnets 2 and 3 interfere with each other, as shown in FIG. 3, the magnetic flux φ81 in the X direction generated by magnet 2 and magnet 3
The magnetic fluxes φ22 in the Y direction generated by the magnetic fluxes φ22 interfere with each other.

Therefore, for example, when the rotating shaft 1 is displaced in the X direction,
The control current of the magnet 2 in the X direction increases or decreases. Magnetic flux φ due to increase/decrease in this control current. A part of the change φ'31 passes through the magnet 3 in the Y direction. In other words, even though the magnetic flux φ21 in the X direction is controlled, as a result of mutual interference, the magnetic flux φ2 in the Y direction
□ also changes.

In order to eliminate the above-mentioned mutual interference, it has been proposed to add a compensation circuit 5 between the magnets 2 and 3 as shown in FIG. However, such a bearing device has a complicated structure, resulting in high cost, and there is a fear that adjustment to eliminate mutual interference between the magnets 2.3 may be complicated.

(Object of the Invention) An object of the present invention is to eliminate the above-mentioned drawbacks and provide a magnetic bearing device with good controllability.

[Summary of the invention]

In order to achieve the above object, the present invention provides a plurality of control magnets adjacent to each other and facing the rotating shaft with an appropriate gap, and modulates the magnetic flux generated from the arbitrary magnet with a control current. The magnetic bearing is characterized in that the adjacent control magnets having the same polarity are disposed adjacent to each other.

[Embodiments of the invention]

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

In FIG. 1, 1 is a rotating shaft, and 2 and 3 are control magnets (permanent stones or electromagnets) that are arranged opposite to the rotating shaft 1 with appropriate gaps in the X and Y directions, respectively, and are adjacent to each other. , these two magnets 2.3 are arranged so that the same poles (in the figure, N poles) are adjacent to each other. 4 is a control circuit attached to the magnet 2.

Since this embodiment is constructed as described above, the magnetic flux φ21. Because of the repulsive force that acts between φ0, the flow of magnetic flux φ'21 as shown in the conventional example (Fig. 3) does not occur, and the magnetic flux that passes through the gap between each magnet 2, 3 and the rotating shaft 1 does not occur. Changes are minimized and each magnet 2, 3
The magnetic flux φ21. φ3. The independence of the flow can be maintained.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to reduce mutual interference between control magnets without using a conventional compensation circuit, improve controllability, and simplify the device to reduce costs. It is possible to reduce the

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an embodiment of the magnetic bearing device of the present invention, and FIGS. 2 to 4 show the configuration of a conventional magnetic bearing device. 1... Rotating shaft, 2.3... Magnet. Figure 1

Claims (1)

[Claims] 1. A magnetic bearing device in which a plurality of control magnets are provided adjacent to each other and are arranged opposite to the rotating shaft with an appropriate gap, and the magnetic flux generated from the arbitrary magnet is modulated by a control current, A magnetic bearing device characterized in that the adjacent control magnets with the same polarity are arranged adjacent to each other.