JP2006149121A - Linear motor - Google Patents

Abstract

The present invention provides a permanent magnet embedded in each yoke of a stator with the same plate thickness direction as the thickness direction of the yoke so as to generate magnetic flux close to a surface magnet type stator. With the goal.
In a linear motor according to the present invention, each permanent magnet (2) embedded in each yoke (1a, 1b) has a thickness direction (t) in the thickness direction of each yoke (1a, 1b). It is arranged to be the same as T), and is configured to obtain the generation of magnetic flux close to the surface magnet type stator (1).
[Selection] Figure 1

Description

  The present invention relates to a linear motor, and in particular, the plate thickness direction of each permanent magnet embedded in each yoke of the stator is arranged in the same direction as the thickness direction of the yoke, and is in a state close to a surface magnet type stator. The present invention relates to a novel improvement for making it easy to freely control the magnetic flux in the gap between the yokes by generating magnetic flux, reducing thrust ripple and improving controllability.

Conventionally used linear motors of this type include the configurations shown in FIGS. 8 and 9 disclosed in Patent Document 1. FIG.
In FIG. 8, the reference numeral 1a indicates one yoke of the elongated stator 1, and a plurality of permanent magnets 2 are embedded in the yoke 1a at predetermined intervals along the length direction L of the yoke 1a. Has been.

  A movable element 3 is arranged so as to be reciprocally movable along the length direction L in a non-contact state with respect to the stator 1, and the movable element 3 is constituted by a claw pole type core 4 and a winding 5 made of a soft magnetic material. It is configured.

  The mover 3 includes a claw pole type core 4, which is located on the winding 5 and has a claw pole part 4 </ b> A having the same width as that of the winding 5, and a previous claw pole part. It is comprised from the core part 4B comprised by parts other than 4A.

  The claw pole part 4 </ b> A constitutes a claw pole type tooth part of the claw pole type core 4.

  Further, in other conventional configurations shown in FIGS. 5 to 7, the same parts as those in the conventional configurations shown in FIGS. 8 and 9 are denoted by the same reference numerals, and description thereof is omitted. The permanent magnet 2 is arranged vertically in each yoke 1a and 1b.

  That is, each permanent magnet 2 embedded in each yoke 1a, 1b has a longitudinal plate shape as a whole, and a plate thickness direction t indicating the thickness indicates the thickness of each yoke 1a, 1b having a longitudinal shape. They are arranged in different directions with respect to the thickness direction T. That is, the permanent magnets 2 are opposed to each other, the magnetic flux is collected in the yokes 1 a and 1 b, and the magnetic flux is generated from the yokes 1 a and 1 b into the longitudinal gap G formed by the gap between the stator 1 and the mover 3.

JP 2004-215414 A

Since the conventional linear motor is configured as described above, the following problems exist.
That is, in any of the conventional configurations described above, when the permanent magnet is embedded in the yoke, the magnetic poles of the permanent magnet face each other in the yoke along the plate thickness direction, so that the stator and the movable magnet are movable. In order to increase the magnetic flux density between the elements, it is necessary to increase the thickness of the permanent magnet. In this case, the magnetic pole width is reduced by the thickness of the permanent magnet, and the magnetic flux from the permanent magnet is fully utilized. It was difficult.

  A linear motor according to the present invention is formed between a pair of yokes that are arranged opposite to each other to form a stator, a plurality of permanent magnets disposed in the yokes at predetermined intervals along a longitudinal direction, and the pair of yokes. In the linear motor comprising a mover wound in a reciprocating manner and wound around a coiled longitudinal gap, each permanent magnet has the same plate thickness direction as the thickness direction of each yoke. The mover is configured to have a claw pole portion, and the mover is formed of a soft magnetic material.

Since the linear motor according to the present invention is configured as described above, the following effects can be obtained.
That is, the permanent magnets embedded in the yoke are arranged so that the plate thickness direction is the same as the thickness direction of the yoke, so that magnetic pole formation similar to that of a conventional surface magnetic flux type stator is performed. In addition, the width of the magnetic pole can be increased, and the magnetic flux in the gap can be freely controlled, so that the thrust ripple can be reduced and the controllability can be improved.
Further, since the width of the magnetic pole is wider than the conventional one, a plurality of windings corresponding to the conventional one are required, but only one corresponding to one is required, and the winding manufacturing process can be simplified.
Further, since the mover is made of a soft magnetic material, a complicated structure having a claw pole portion can be easily obtained.

  In the present invention, the thickness direction of the permanent magnet embedded in the yoke is made the same as the thickness direction of the yoke, so that the magnetic pole can be formed in the same manner as a conventional surface magnetic flux type stator. An object of the present invention is to provide a linear motor in which the magnetic flux in the longitudinal gap can be freely controlled by widening the width.

Hereinafter, preferred embodiments of a linear motor according to the present invention will be described with reference to the drawings.
In addition, the same code | symbol is attached | subjected and demonstrated to a part the same as that of a prior art example, or an equivalent part.
In FIG. 1, what is indicated by reference numeral 1 is a longitudinal stator composed of a pair of first and second yokes 1a and 1b which are positioned to face each other with a gap G interposed therebetween. A plurality of permanent magnets 2 are embedded along the longitudinal direction L at predetermined intervals.

  As shown in FIGS. 3 and 4, each permanent magnet 2 has a configuration in which the overall shape is a longitudinal flat plate shape, and the thickness direction t indicating the thickness direction is the thickness of each yoke 1a, 1b. It is the same direction as the thickness direction T indicating the direction of

The arrangement of the permanent magnet 2 differs only in that it is embedded in each of the yokes 1a and 1b, and the conventional surface magnetic flux type (for example, the disclosure of FIG. 4 in JP-A-2004-215414) is fixed. Magnetic poles are formed on the opposing surfaces in the thickness direction t so that the same magnetic pole formation as that of the child can be performed.
Accordingly, the magnetic flux in the longitudinal gap G composed of a gap can be freely controlled by increasing the width of the magnetic pole.

A movable element 3 shown in FIG. 2 is reciprocally disposed in the longitudinal gap G. The movable element 3 is a claw pole type having windings 5 inside a plurality of claw pole portions 4A. The soft magnetic material is configured to have a three-dimensional shape.
The movable element 3 is not limited to the claw pole type, and a magnetic pole configuration not having the claw pole portion 4A can also be used.

Further, the material of the stator 1 and the mover 3 is made of a soft magnetic material, and a laminated steel plate / sintered powder magnetic material is used as a structure thereof, or only the sintered powder magnetic material is formed. ing.
Moreover, although the said coil | winding 5 is a three-phase structure, it is comprised by one piece for every phase instead of several windings per phase.

  As specifically shown in FIG. 2, the claw pole portion 4A has a triangular or trapezoidal shape whose width decreases from the base portion toward the tip, and a groove 3A between the claw pole portions 4A. The shape of is not orthogonal to the longitudinal direction of the mover 3 but is formed in a non-orthogonal state, that is, diagonally.

  The present invention is applicable not only to a linear motor but also to a linear actuator.

It is a perspective view showing a linear motor according to the present invention. It is a perspective view which shows the needle | mover of FIG. It is a front view which shows a magnetic pole seeing the structure of FIG. 1 from the front. It is an enlarged view which shows the principal part of FIG. It is a perspective block diagram which shows the conventional linear motor. It is a front view which shows a magnetic pole seeing the structure of FIG. 5 from the front. It is an enlarged view which shows the principal part of FIG. It is a perspective view which shows the principal part of the linear motor which shows another prior art example. It is a perspective view which shows the needle | mover of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Stator 1a 1st yoke 1b 2nd yoke 2 Permanent magnet 3 Movable element 4A Claw pole part 5 Winding G Longitudinal gap t Thickness direction T Thickness direction

Claims (3)

A pair of yokes (1a, 1b) which are arranged opposite to each other and constitute the stator (1), and a plurality of permanent magnets (2) arranged in the yokes (1a, 1b) at predetermined intervals along the longitudinal direction And a linear motor comprising a movable element (3) around which a winding (5) is wound so as to be reciprocally movable in a longitudinal gap (G) formed between the pair of yokes (1a, 1b). In
Each of the permanent magnets (2) is arranged such that the thickness direction (t) thereof is the same as the thickness direction (T) of each of the yokes (1a, 1b). .   The linear motor according to claim 1, wherein the movable element (3) has a claw pole portion (4A).   3. The linear motor according to claim 1, wherein the mover is made of a soft magnetic material.

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