JPS62126856A - Linear motor - Google Patents

Abstract

PURPOSE:To increase a magnetic flux density from a permanent magnet and to prevent the magnet from being demagnetized by providing a primary side for generating a moving magnetic field and a secondary side having a plurality of permanent magnets and cores, and magnetizing the magnets in predetermined states. CONSTITUTION:The secondary side 20 of a linear motor is composed of a frame 21, a plurality of rectangular secondary cores 22 and platelike permanent magnets 23 mounted on the frame 21. The cores 22 and the magnets 23 are alternately disposed along the moving direction of the primary side 1 or the secondary side 20, the cores 22 are interposed between the same polarity pole faces of the magnets 23 and the faces of the cores 22 facing the primary side 1 thus alternately become N-pole and S-pole surfaces. The size of the set of the cores 22 and the magnets 23 along the moving direction of the primary side 1 or the secondary side 20 is equal to the pole pitch tau of the primary side 1. The height side H of the magnet 23 can be increased with this construction without limit.

Description

Detailed Description of the Invention "Field of Industrial Application" This invention relates to a linear motor that directly converts electrical energy supplied from the outside into linear mechanical energy, and in particular, relates to a linear motor that directly converts electrical energy supplied from the outside into linear mechanical energy, and in particular, a linear motor that has a permanent magnet inside the rotor. This relates to a built-in permanent magnet type synchronous motor and a linear motor that operates on the same principle.

"Conventional technology" Conventional permanent magnet type synchronous 71! [11312! Figure 4 (a) and (a) show a linear motor with a structure in which
The ones shown in b) are known. In these figures,
1 is the primary side, 1 over 2a, 2a... and grooves 2b, 2
A primary side core 3 made up of 11 layers of punched electric iron plates 2.2... and each it+T 2 b, 2
Coils 4 u, 4 v, respectively wound in b...
4 W andkara (1 ■ [Haved.

Here, if one 3tll alternating current is picked up in the coils 4u, 4v, and 4v, a magnetic field (magnetic flux density) is generated that advances in the direction of arrow A or +3 in the figure. The IS wavelength (half-circle JCI+ length) of this traveling magnetic field is particularly important for the pole pitch (pole pitch).
pitch) τ. On the other hand, 6 is a secondary side which faces the primary side 1 with a gap G in between, and has a long J, (temporary 7 and a ?U-shaped plate attached adjacent to this board 7). It is composed of permanent magnets 8, 8... In this case, each permanent magnet 8, 8... has the same length dimension as the pole pitch, and their N, I, and S poles. The surfaces are alternately arranged so as to face the primary side 1. Also, although not shown in the figure, a gap G is maintained between the primary side 1 and the secondary side 6. 1 (in addition, supporting machines that support each other in a freely movable manner in the direction of arrow A or B shown in the figure)
'4 is provided. With such a configuration, for example, the primary side 1 is fixed and the coils 4 u, 4 v, 4
When 3-river alternating current is supplied to vs, permanent magnetic C1 shadow synchronization tI
ll! Based on the same dynamic principle as in the machine, the secondary side 6 moves in the direction of the arrow Δ or B in synchronization with the 1λ dynamic speed of the generated magnetic field. Similarly, the primary side 6
If fixed, primary side 1 can be moved.

By the way, in a linear motor configured as -1 = + 1-, in order to efficiently generate thrust K), the permanent magnet 8.8 on the secondary side 6 must be It is required to increase the magnetic flux density generated from... However, since it has a structure in which permanent magnets 8°8 are arranged side by side, there is a problem in that expensive precious earth magnets must be used in order to increase the magnetic flux density.

In addition, each magnetic surface of the permanent magnets 8, 8... is the primary side 1 and 21.
Because it is facing the same direction, the coil 111,
When an inrush current flows through ・1ν, ・Iw, the primary core 3
There was a problem in that the magnetic flux emitted from the 1''5 teeth 2a, 2a of the magnet 8 travels within the permanent magnet 8, causing the permanent magnet 8 to be demagnetized.

This invention was made in view of the above-mentioned circumstances, so that when the magnetic flux density generated from the permanent magnet on the secondary side becomes large, the magnetic flux generated on the primary side causes the permanent magnet on the secondary side to The purpose is to provide a linear motor that does not become demagnetized.

"Means for Solving the Problems" This invention provides a primary side of a soil filter that generates a traveling magnetic field, and the following...
Suno & Li field generators are opposed to each other across a face gap, and are arranged alternately along one multi-force direction of the traveling magnetic field described in 11J1. Each of the permanent magnets is characterized in that the respective surfaces of the valley core facing the primary side are magnetized so as to alternately serve as a north pole face and a south pole face.

1 action" The dimensions of each permanent magnet in the direction perpendicular to the magnetic field generation surface on the primary side can be adjusted to an unlimited size, so the magnetic flux density can be varied greatly, and the magnetic flux generated on the primary side Since the permanent magnet passes through the core of the secondary side, the permanent magnet will not be demagnetized even if an inrush current is supplied to the primary side at the same time.

"Embodiments" Hereinafter, embodiments of the present invention will be explained 1 with reference to the drawings.
'reactor,.

Figures 1 (a) and (b) are 10 diagrams showing the configuration of one embodiment of the present invention, and each part in Figures 1 (a) and (b) is
The same IT, j; is attached to the part corresponding to 4', and the explanation thereof is 6 or 4-ro.

In these figures, 20 is the secondary side of the linear motor, for example, non-magnetic material such as aluminum (4 materials, J, (1)
The frame 21 that has been made and the frame 21 that is
(Also) Rectangular parallelepiped secondary core with 9 losses 22.22
and temporary permanent magnets 23, 23... In this case, the secondary cores 22, 22... and the permanent magnets 23, 23 are the primary I or the secondary 1! III G of I) Intersect 1 along the YJJ direction (arrow A or B direction)
1 and 1ζ, each secondary core 22.22 is oriented 111 by the same polar plane of the permanent magnet 23.23, respectively.
As a result, h secondary side core 22, 22... primary side 1
The 2nd and 2nd valley sides are alternately N and S compositions. Further, the dimension of one pair of secondary side 1a 22 and permanent magnet 23 along the moving direction of the primary side 1 or the secondary side 20 is equal to the pole pivot r of the primary side 1.

According to such (+ growth), the height dimension I of each permanent magnet 23 is 5.
11 methods perpendicular to one magnetic field generation surface by 4 degrees! 1 to 11
Since it is possible to deviate from 1 degree to 4 degrees within the limit, the magnetic flux density can be increased by using a high f+lli noble class 2 magnet or the like, or by using a cheap 1dlI ferrite magnet or the like.

In addition, when an inrush current flows through the coils Iu, 4v, and 4w during startup, etc., the
Since the magnetic flux emitted from 442 n, 2 a passes through each secondary core 22, 22..., the permanent magnet 23 does not move 711'dl as in the conventional case.

Next, FIGS. 2 and 3 are diagrams showing the construction of the pond according to the second embodiment of the invention.

``In FIG. 2, the points that differ from the above-mentioned embodiment are as follows.
The height of the convex permanent magnet 23 is made lower than the primary core 22, and the g1 portion of the secondary core 22 is removed to form the slope 2.
It is at the point where 2a was formed. By doing this, the distribution state of the magnetic flux density generated from the permanent magnet 23.23 and spread within the air gap G approaches a sine waveform, so that the so-called torque ripple is reduced, and the operation during low continuous movement. Stabilization will be attempted.

Next, in FIG. 3, the 4-frame 1 (
Install a pair of primary sides 1a and LB by folding the secondary side 20a with ζ21 removed. In this figure, if the voids Ga and G l) are kept 111, then 1
The supporting mechanism is omitted in the figure.J5 is located between the secondary side 20a and the pair of primary sides 1a and Ib, and the ends of each other are supported at J+'E. According to this, the suction forces of the primary sides 1a and 1b are generated in opposite directions, so that an R-like balance can be achieved.

In the six embodiments described above, the primary side! and secondary side 20
The positional relationship of t11σ in (20a) is detected, and based on the detected signal, the excitation of the coils 4u, 1v, and 4w is controlled. Ru. 1. In order to reduce the cogging force, the same as the skew in general rotation (L1), the secondary side core 22 and the permanent magnet 23 are connected to the primary side 1 or the secondary side 20.
1, it is only necessary to arrange it so that it is not in one direction but at an angle with respect to the direction of movement.

"Effects of the Invention" As explained above, according to the present invention, a primary side that generates a traveling magnetic field and a magnetic field generating surface of the primary side are opposed to each other across an air gap, and 1; II: j old permanent magnets are arranged alternately along the primary side of each of the cores. Each of the 4 opposing surfaces alternates with the N-pole surface and s
Since the celadon magnetism (1) is so as to be +b, the dimension of each permanent magnet in the direction perpendicular to the primary side magnetic field generation surface can be increased without limit. The magnetic flux density can be increased even when using This has the effect that permanent magnets do not demagnetize when placed in a magnet.

[Brief explanation of drawings]

FIG. 1(a) is a partially cutaway front view showing the configuration of an embodiment of the present invention, FIG. 1(b) is a sectional view taken along line C-C in FIG. 1(a), and FIG. and FIG. 3 is a partially cutaway front view showing the configuration of another embodiment of the present invention, and FIG. 1 (A)
shows the configuration of the linear motor since Tit-J-iE surface,
FIG. 4(B) is a view taken along line D-1) of FIG. 4(A). 1...Primary side, 2a...1''19 (magnetic field generation surface), 20...Secondary side, 22...Secondary side core, 23
...Permanent magnet, 2! ...Frame, G...Void.

Claims (1)

[Claims] a primary side that generates a traveling magnetic field, and a secondary side that faces the magnetic field generation surface of the primary side across an air gap and is made up of a plurality of permanent magnets and cores arranged alternately along the moving direction of the traveling magnetic field. A linear motor, characterized in that each of the permanent magnets is magnetized so that each surface facing the primary side of each core is alternately a N-pole surface and an S-pole surface.