JPS5980140A - Permanent magnet rotor with starting winding - Google Patents

Abstract

PURPOSE:To enhance the efficiency by providing a starting winding, disposing a spacer and a nonmagnetic unit between permanent magnets, thereby facilitating the start and reducing the leakage magnetic flux. CONSTITUTION:A magnetic flux generated from a permanent magnet 6 is passed through the part of a magnetic unit 9 of a shell 11, further through a magnetic path of a stator side via an air gap from a stator, fed again through the air gap, from the part of the magnetic unit 9 of the shell of the adjacent permanent magnet 6 into the permanent magnet 6, and returned through a rotor core 1 to the original permanent magnet 6. Since a nonmagnetic material 10 is disposed between the magnetic units 9 and 9 to form the shell 11, the magnetic flux is not leaked through the material 10, thereby improving the efficiency of a motor. A starting winding 5 is provided at the core 1, thereby facilitating the starting of the motor.

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to a permanent magnet rotor with a starting winding.

[Technical background of the invention and its problems]

Conventionally, a permanent magnet rotor having a starting winding has been proposed in which the starting winding is formed by die-casting on the rotor core, and the permanent magnets are bonded to the outer periphery of the rotor core with adhesive. . However, in the rotor of an ultra-high-speed electric motor that can rotate tens of thousands of revolutions per minute, which has been in high demand in recent years, the above structure reaches a certain limit in terms of strength against centrifugal force.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a permanent magnet rotor having a starting winding that improves mechanical efficiency when assembled into an illumination machine and has sufficient strength for ultra-high speed rotation.

[Summary of the invention]

In the present invention, a rod-shaped conductor is disposed in the axial hole of a rotor core having a cylindrical shape and a plurality of axial holes arranged in the circumferential direction, and both ends of the rod-shaped conductor are connected by end rings. An even number of permanent magnets and spacing pieces made of a non-magnetic material are arranged alternately in the circumferential direction on the outer periphery of the rotor core, and both axial ends of the permanent magnets and the spacing pieces are arranged on the outer periphery of the rotor core. an annular body made of a non-magnetic material is disposed on the outer periphery of the permanent magnet, the spacing piece, and the annular body, the part that abuts the outer surface of the permanent magnet is made of a magnetic material, and the part that abuts the outer surface of the spacer M piece; is made of non-magnetic material, and a cylindrical shell made by welding this magnetic material and non-magnetic material is fitted into the rotor core to cover the starting winding and the sides of the annular body on both sides in the axial direction of the rotor core. By providing an annular plate which welds together the inner circumferential iron core part, the axial end of the shell, and the annular body further from the inner periphery of the ring, the centrifugal force of the permanent magnet and the spacing piece is carried by the shell, and the shell is attached to the annular body. The rotor is integrated with the rotor core through an annular plate to create a rotor that is safe and strong against ultra-high speed rotation, and the magnetic flux of the permanent magnets passes through the magnetic material to the stator core, and the spacer pieces and non-magnetic material are connected to the adjacent The rotor is placed between permanent magnets to reduce leakage magnetic flux, resulting in a highly efficient rotor.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

(1) is a cylindrical rotor core made of laminated thin iron plates,
A plurality of axial holes (2) are arranged in the circumferential direction, and a rod-shaped conductor (3) made of a copper rod is arranged in the axial holes (2). Copper annular end rings (4) are soldered with silver to both ends of the rod-shaped conductor (3) to form a squirrel-shaped starting winding (5). (6) is an arc-shaped permanent magnet, and uses an even number (four in the figure) of 12 mm thick rare earth cobalt magnet Toslex (trade name manufactured by Toshiba Corporation), which has a high magnetic energy product. Non-magnetic spacing pieces (7) made of stainless steel are alternately attached to the outer periphery of the iron core (1) with adhesive. A non-magnetic annular body (8) made of stainless steel is disposed at a position that abuts the outer periphery of the end ring (4) at both axial ends of the permanent magnet (6) and the spacing piece (7). A permanent magnet (6) is placed on the outer periphery of the permanent magnet (6), the spacing piece (7), and the annular body (8).
) is made of a strip-shaped magnetic material (9) made of magnetic special alloy steel, and the part that comes into contact with the outer surface of the spacing piece (7) is made of a strip-shaped non-magnetic U made of non-magnetic special alloy steel.
' (10) joined by electron beam welding with a thickness of 3.5
A cylindrical shell aυ of mm is fitted. Rotor core (
1), the starting winding (5) and the annular body (8
), and weld the core part 0 on the inner peripheral side of the end ring (4), the axial end of the shell 01), and the annular body (8) through the annular plate (+3). ” are combined to make the rotor into a strong one piece. This annular plate Q3) may be made of magnetic or non-magnetic material.

Next, the effect will be explained.

The magnetic flux generated from the permanent magnet (6) passes through the magnetic body (9) of the sheath/I/(11) as shown by the arrow in FIG.
After passing through the magnetic path on the stator side (not shown) through the air gap with the stator (not shown), the magnetic material (9) of the shell of the neighboring permanent magnet (6) passes through the air gap again It enters the magnet (6), passes through the rotor core (1), and returns to the original permanent magnet (6). Since the non-magnetic material (10) is placed between the magnetic materials (9) and (9) to form a shell aυ, magnetic flux will not leak through this non-magnetic material <1.0). This improves the efficiency of the electric motor. Furthermore, since it has a starting winding (5), it starts extremely smoothly and the motor becomes easy to operate. In addition, the permanent magnet (6) is connected to the spacer piece (
7) is fixed to the rotor core (1) with adhesive and further welded to the outer circumference of the shell αυ. Since it is fixed to the iron core (1) by welding, it can sufficiently withstand the centrifugal force of ultra-high speed rotation. That is, the shell αυ, the toroid (
8) is welded to the rotor core (1) via the annular plate a3), so that the parts of the permanent magnet (6) and the spacing piece (7) that are glued to the rotor core (1) are separated by centrifugal force. However, since it is integrated with the rotor core, its mechanical strength is sufficiently safe. Moreover, the annular body (8) does not compensate for the strength of the end ring (4), which has weak mechanical strength, and the shell (II)
It also strengthens the strength of the permanent magnet (6) and prevents the heat generated during welding from being transmitted to the permanent magnet (6), making it extremely effective. There is no risk of damage due to mechanical impact.Incidentally, with this structure, 4 poles - 37KW - 2000Or, 1), m.

This made it possible to manufacture electric motors with specified specifications.

The present invention is not limited to the embodiments described above and shown in the drawings, but may be modified in various ways, such as by changing the number of poles or the thickness of the shell, without changing the gist thereof. Of course, it can be implemented by

〔Effect of the invention〕

As explained above, according to the present invention, starting is easy due to the starting winding, high efficiency is achieved due to low leakage magnetic flux of the permanent magnet, and the shell and the annular body are rotated through the annular plate. By welding to the child core, it is possible to provide a permanent magnet rotor that is mechanically strong and has a starting winding that rotates at an ultra-high speed without causing any thermal effects on the permanent magnets during welding.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a permanent magnet rotor having a starting winding according to the present invention, and FIG. 2 is a cross-sectional view of a main part taken along line A--A in FIG. 1. 1... Rotor core 2... Axial hole 3... Rod-shaped conductor 4... End ring 5... Starting winding 6
... Permanent magnet 7 ... Spacing piece 8 ... Annular body 11 ... Shell 12 ... Inner peripheral side iron core part 13
... Annular Board Agent Patent Attorney Ito -Male

Claims (1)

[Claims] A starting winding is provided in which a rod-shaped conductor is disposed in the axial hole of a rotor core having a cylindrical shape and a plurality of axial holes arranged in the circumferential direction, and both ends of the rod-shaped conductor are connected with end rings. An even number of permanent magnets and spacing pieces made of a non-magnetic material are arranged alternately in the circumferential direction on the outer periphery of the rotor core, and a non-magnetic material is placed on both axial ends of the permanent magnets and the spacing pieces. A ring-shaped body is disposed on the outer periphery of the permanent magnet, the spacing piece, and the ring-shaped body, and the part that contacts the outer part (1) of the permanent magnet is made of a magnetic material,
The part that contacts the outer surface of the spacer piece is made of a non-magnetic material, and a cylindrical shell made by welding this magnetic material and a non-magnetic material is fitted, and a starting winding and an annular shell are fitted on both sides of the rotor core in the axial direction. A permanent magnet having a starting winding, which includes an annular plate that covers the side surface of the body and welds together the core part on the inner peripheral side of the end ring, the axial end of the shell, and the annular body by welding. rotor.