JP2002010610A - Linear motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To materialize a linear motor which is small and has a high efficiency by easily and precisely laminating electromagnetic steel plates 22 having projections 30 on them. SOLUTION: The laminated stator core 14 of the linear motor 10 consists of two kinds of the electromagnetic steel plates 22 which are formed in a specified shape having each a plurality of projections 30 in the same direction at the outer side portions of the center and are alternately laminated in radial by avoiding a lap of these projections 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear motor,
In particular, the present invention relates to a linear motor including a laminated stator core formed by, for example, radially laminating electromagnetic steel sheets.

[0002]

2. Description of the Related Art Conventionally, when forming an arc-shaped outer yoke to be a laminated stator core of a linear motor, for example, rectangular electromagnetic steel plates are radially laminated to form a cylindrical laminated core. However, when electromagnetic steel sheets are laminated radially,
Because of the inner and outer diameters, a wedge-shaped space exists between the magnetic steel sheets, which not only complicates assembly but also degrades accuracy. That is, it has been difficult to form a laminated iron core by laminating electromagnetic steel plates with high accuracy in a radial manner.

For this purpose, for example, as shown in FIGS. 9 to 11, an outer yoke 3 constituting a laminated iron core 2 of a linear motor is made of an electromagnetic steel plate 4 having a substantially rectangular shape and high magnetic permeability.
And a columnar second yoke obtained by combining a single or a plurality of block-shaped first yoke members 5 each having a curved surface in the direction of the central axis formed by stacking a large number of them and a block member 6 having a high magnetic permeability and a sector shape. The members 7 are arranged alternately to form a cylindrical shape. The block material 6 has an insulating film on the surface.

[0004]

The outer yoke 3
The inner yoke arranged with a predetermined gap inside is also configured in the same manner as the above-described outer yoke 3, and for example, an exciting coil is mounted on the inner yoke and a permanent magnet body is movably arranged in the predetermined gap. Is a movable magnet type linear motor.

For this purpose, it is necessary to manufacture the first yoke member 5 and the second yoke member 7 in advance, and there is a problem that the cost is increased.

SUMMARY OF THE INVENTION Accordingly, it is a primary object of the present invention to provide a small and efficient linear motor having a laminated stator core formed by laminating electromagnetic steel plates with high accuracy in a simple configuration.

[0007]

SUMMARY OF THE INVENTION The present invention is directed to a laminated stator core having electromagnetic steel plates of a predetermined shape radially laminated and having a predetermined gap, an exciting coil mounted on the laminated stator core, and movable in the predetermined gap. A linear motor having freely movable movable bodies, wherein the laminated stator core is formed by laminating electromagnetic steel sheets provided with at least one protrusion in the same direction.

[0008]

The magnetic steel sheets forming the laminated stator cores are provided with protrusions, and the protrusions can be arranged radially easily by changing the distance between the magnetic steel sheets according to the inner and outer diameters of the iron cores.

[0009]

According to the present invention, electromagnetic steel sheets can be easily and accurately laminated radially. By radially laminating the magnetic steel sheets, the magnetic circuit of the laminated stator core can be used effectively spatially, and a small and highly efficient linear motor can be realized.

The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the accompanying drawings.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A movable magnet type linear motor 10 according to an embodiment of the present invention shown in FIG. 1 has a laminated stator core 14 having a predetermined gap 12, an exciting coil 16 mounted on the laminated stator core 14, and a laminated core. The permanent magnet body 18 is movably disposed in the predetermined gap 12 of the stator core 14. The permanent magnet body 18 is held by a non-magnetic hollow cylindrical magnet holding member 20 which is open on one side, and is fixed to a shaft (not shown) positioned at the center axis CC.

The laminated stator core 14 has an arcuate inner yoke 24 formed by radially laminating electromagnetic steel plates 22 formed in a substantially U-shape. One end is connected to the inner yoke 24 and the other end is connected to the inner yoke 24. And an arc-shaped outer yoke 28 formed by radially laminating substantially L-shaped electromagnetic steel sheets 26 forming the predetermined gap 12 therebetween.

The substantially U-shaped electromagnetic steel plate 22 constituting the inner yoke 24 has protrusions 30 and 3 in the same direction at different positions outside the central axis CC as shown in FIG.
0, and the electromagnetic steel plates 22 are radially and accurately laminated by these projections 30. Also, as shown in FIG. 4, the substantially L-shaped electromagnetic steel plate 26 constituting the outer yoke 28 is also provided with protrusions 32 and 32 in the same direction at two places, and the electromagnetic steel plate 26 is radially formed by these protrusions 32. It is laminated with high accuracy.

That is, it is possible to arrange the electromagnetic steel plates 22 and 26 radially by providing the protrusions 30, 30 and 32, 32 on the electromagnetic steel plates 22 and 26, and changing the interval between the electromagnetic steel plates 22 and 26 according to the inner and outer diameters of the laminated stator core 14. Becomes After the electromagnetic steel plates 22 and 26 are radially arranged, the upper and lower ends are welded or fixed to each other by, for example, welding or fixing rings.

The projections 30, 30 and 32, 32
Are provided at the same time when the electromagnetic steel sheets 22 and 26 are punched out of the electromagnetic steel strip into predetermined shapes. Then, as shown in FIG. 5, the positions of the projections 30, 30 are shifted, for example, 2
The inner yoke 24 is configured by alternately stacking the types of electromagnetic steel plates 22 and radially stacking them so that the projections do not overlap. Similarly, when forming the outer yoke 28, two types of electromagnetic steel plates 26 in which the positions of the projections 32, 32 are shifted may be alternately laminated in a radial pattern.

In the above embodiment, the protrusion 30
Or 32 is formed at the same time when the electromagnetic steel sheet 22 or 26 is punched out of the electromagnetic steel strip, so that the protrusions 30 or 32 must be prevented from overlapping at the time of lamination. Later, as a protruding member, for example, a metal member is replaced with the electromagnetic steel plate 22 or 2
6 or by attaching resin material,
When the protrusions are formed, the protrusions can be stacked in an overlapping state.

In the above-described embodiment, the movable magnet type linear motor 10 using the one-side open type laminated stator core 14 has been described. However, the movable magnet using the two-side open type laminated stator core 14 shown in FIG. The present invention is also applicable to the linear motor 10.

That is, as shown in FIG. 6 only on one side by a central axis CC, a substantially cylindrical inner yoke 24 is formed by radially laminating electromagnetic steel plates 22 having a substantially U-shaped cross section. A cylindrical outer yoke 28 which is disposed with the inner yoke 24 and the predetermined gap 12 and radially laminated substantially rectangular electromagnetic steel plates 26, and an excitation coil provided inside the inner yoke 24. 16 and a permanent magnet body 18 movably disposed in a predetermined gap 12 between the inner yoke 24 and the outer yoke 28. This permanent magnet body 18 is also held by a non-magnetic hollow cylindrical magnet holding member and fixed to a shaft similarly to the embodiment of FIG.

The magnetic steel plates 22 and 26 are provided with protrusions 30 and 32, respectively, as in the above-described embodiment, and the protrusions 30 and 32 allow the inner and outer diameters of the laminated stator core 14 to be adjusted. The magnetic steel sheets are laminated radially by changing the interval between them.

Although the embodiment has been described with respect to the movable magnet type linear motor 10 in which the permanent magnet body 18 is disposed as a movable body in the predetermined gap 12 of the laminated stator core 14, the movable magnet linear motor 10 is movable in the predetermined gap 12 of the laminated stator core 14. Coil 3 as body
4 moving coil type linear motor or iron core 3
6 can also be applied to a movable core linear motor. In the former case, as shown in FIG. 7, a permanent magnet 36 is mounted on the laminated stator core 14 instead of the exciting coil 16, for example, on the inner surface of the outer yoke 28. In the latter case, as shown in FIG. 8, permanent magnets 36 and 36 are mounted on the inner surfaces of the inner yoke 24 and the outer yoke 28 forming the predetermined gap 12, respectively. In the figure, the projections of the electromagnetic steel sheets that are laminated radially and constitute the laminated stator core 14 are not shown.

As described above, in the linear motor of the present invention, since the electromagnetic steel sheets constituting the laminated stator core are provided with the protrusions, the electromagnetic steel sheets can be radially stacked with high accuracy. By radially stacking, the magnetic circuit can be used spatially and effectively, and as a result, a small and highly efficient linear motor can be realized.

[Brief description of the drawings]

FIG. 1 is an illustrative view of a one-side open type movable magnet type linear motor showing an embodiment of the present invention.

FIG. 2 is a plan view of an electromagnetic steel plate constituting an inner yoke shown in FIG.

FIG. 3 is a sectional view taken along line AA in FIG. 2;

FIG. 4 is a plan view of an electromagnetic steel plate constituting an outer yoke in FIG. 1;

FIG. 5 is an explanatory view of a main part in a case where electromagnetic steel sheets provided with protrusions are stacked.

FIG. 6 is an illustrative view of a movable magnet type linear motor having both ends open, which is another embodiment.

FIG. 7 is an illustrative view of a moving coil type linear motor showing still another embodiment.

FIG. 8 is an illustrative view of a movable iron core type linear motor showing still another embodiment.

FIG. 9 is an illustrative view of a relevant part of a conventional laminated stator core.

FIG. 10 is a perspective view of the first yoke member of FIG. 9;

FIG. 11 is a perspective view of the second yoke member of FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Movable magnet type linear motor 12 ... Predetermined air gap 14 ... Laminated stator iron core 16 ... Exciting coil 18 ... Permanent magnet body 22,26 ... Electromagnetic steel plate 24 ... Inner yoke 28 ... Outer yoke 30,32 ... Protrusion

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kazuki Hida 2-5-5 Keihanhondori, Moriguchi-shi, Osaka F-term in Sanyo Electric Co., Ltd. (reference) 5H002 AA00 AA07 AB01 AB05 AC00 AC02 5H633 BB07 BB08 BB10 GG02 GG04 HH02 HH03 HH07 HH16 HH18 HH21 HH22

Claims (4)

[Claims] 1. A laminated stator core having electromagnetic steel plates of a predetermined shape radially laminated and having a predetermined gap, an exciting coil mounted on the laminated stator core, and a movable body movably disposed in the gap. In the linear motor, the laminated stator core has at least one protrusion in the same direction.
A linear motor, comprising a plurality of electromagnetic steel sheets laminated. 2. The linear motor according to claim 1, wherein the electromagnetic steel sheets include at least two types of steel sheets provided with protrusions in the same direction at different positions, and are alternately stacked. 3. The linear motor according to claim 1, wherein the protrusion is provided at a portion closer to an outer shape than a center side of the magnetic steel sheet. 4. The linear motor according to claim 1, wherein said movable body includes one of a magnet body, a coil, and an iron core.