JP4380192B2 - Permanent magnet array for linear motor and linear motor using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a permanent magnet array for a linear motor and a linear motor using the same, and more particularly to a cooling structure thereof.
[0002]
[Prior art]
A linear motor including a linear stator, a pair of movers that can move independently of each other along the stator, and a guide that guides the movers along the stator is known (for example, Patent Document 1). reference).
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 2001-198873
FIGS. 5 and 6 are diagrams illustrating the linear motor portion disclosed in Patent Document 1, in which FIG. 5 is a front view of the linear motor, and FIG. 6 is a fixing in which a large number of permanent magnets are fixed to a stator. 5A is a cross-sectional view taken along the line AA in FIG. 5, FIG. 5B is a cross-sectional view taken along the line BB in FIG. 5, and FIG. 5C is a perspective view of the single permanent magnet 2 used therein. FIG.
In both figures, 1 is a stator, 2 is surrounded by a dotted line, 2 is a permanent magnet incorporated in the stator 1, 3 (3a, 3b) is a mover incorporating a coil (not shown), and 4 is a slider 8 and a guide rail. 9 is a head of the length measuring system, 6 is a scale of the length measuring system, and 10 is a permanent magnet holder for holding the permanent magnet 2. The stator 1 has a large number of permanent magnets 2 fixed to a main body made of an aluminum alloy that is a nonmagnetic material.
As can be seen from (c), the single permanent magnet 2 has a rectangular shape, and a large number of the permanent magnets 2 are arranged so that the polarities thereof are alternately different in the direction perpendicular to the paper surface of FIG. 5 (in the left-right direction in FIG. 6 (a)). One of the side surfaces is magnetized to the N pole and the other is magnetized to the S pole, and the N pole and the S pole are arranged adjacent to each other at a constant interval (see FIG. 6B).
Each of the pair of movers 3a and 3b includes two iron cores facing the front side and the back side of the stator, respectively. The iron cores are connected to each other across the stator 1 to form a U-shape as a whole (this configuration Is not shown).
Each iron core is wound with a U-phase, V-phase, and W-phase coil to constitute a coil unit. Each coil unit is controlled by the armature current so as to generate a direct power for moving the mover linearly along the stator by the interaction between the magnetic force generated by each coil and the magnetic force of the permanent magnet of the stator. It is configured.
The movement of the movers 3a and 3b is guided by linear motion bearings 4 fixed to both the front and back surfaces of the stator 1, respectively.
[0005]
[Problems to be solved by the invention]
However, the permanent magnet array according to the prior art has the following problems.
1) The stator, which is a permanent magnet array, has no cooling structure.
2) Therefore, heat is transferred from the two armatures (movable elements) 3a and 3b, which are heat generation sources, to the stator 1 through the bearing 4 and by radiation, and heat is easily stored.
3) Large heat conduction to the load due to lack of cooling.
SUMMARY OF THE INVENTION An object of the present invention is to solve these problems, and to provide a permanent magnet array for a linear motor that can improve the cooling performance of the motor and keep heat conduction to a load low, and a linear motor using the same. It is in.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, a permanent magnet array for a linear motor according to claim 1 is characterized in that a plurality of permanent magnets having different polarities are alternately arranged side by side at a predetermined interval, and the permanent magnets are arranged around the permanent magnets. In the permanent magnet array for a linear motor surrounded by a holding body, the permanent magnet has a recess in a central side surface between adjacent NS magnetic poles, and a cooling space is provided in the recess, and the permanent magnet There Rutotomoni consists magnet divided into two parts to one another, the shape of each permanent magnet divided into two parts to each other, characterized in that the tip is configured in a shape in which the convex or concave or curved shape.
By providing the cooling space between the permanent magnets in this manner, the performance of the motor is improved, the heat conduction to the load can be kept low, the cooling space can be widened, and the manufacture becomes easy.
According to a second aspect of the present invention, in the permanent magnet array for a linear motor according to the first aspect , the shape of each permanent magnet has a hexagonal cross section of a base plate shape. Magnet array.
By doing so, it is advantageous that the cooling space can be effectively made large.
The invention of a linear motor according to claim 3 has the permanent magnet array for linear motor according to claim 1 or 2 , and the armature provided on both sides of the permanent magnet array for linear motor. And
A linear motor with good performance can be obtained by using a stator having a cooling space between such permanent magnets.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[First Embodiment]
FIG. 1 is a front view of a linear motor according to the present invention, FIG. 2 is a diagram for explaining a stator according to a first embodiment, (a) is a cross-sectional view along BB in FIG. 1, and (b). FIG. 3 is a perspective view of a permanent magnet alone. In addition, description is abbreviate | omitted about the same thing as the component of this invention, and a different thing is demonstrated.
1 and 2, reference numeral 7 denotes a cooling space provided by the present invention. This cooling space 7 extends in the vertical direction of the stator 1 and penetrates, and the natural heat of the air is generated from the bottom to the top by the heating of the permanent magnet 2, and the air takes away the surrounding heat and the air from above. Heat will be released inside.
Therefore, the drawback of the permanent magnet array according to the prior art, which is a problem of large heat conduction with respect to the load, is solved by the natural convection of air by the cooling space 7.
[0008]
[Second Embodiment]
FIG. 3 is a view showing a permanent magnet array according to the second embodiment. This feature is obtained by changing the shape of the permanent magnet to the NS magnetic pole of the permanent magnet as shown in the perspective view 2 ′ of FIG. It is the point made into the shape which provided the hollow 2'a in the center side surface between.
When a plurality of permanent magnets 2 'having such a shape are arranged as shown in FIG. 3A, a wide cooling space 7' is formed between the permanent magnet 2 'and the adjacent permanent magnet 2'. Can do. Therefore, in this embodiment, the heat transfer area (cross-sectional area) of the cooling space 7 ′ larger than the heat transfer area (cross-sectional area) of the cooling space 7 of the first embodiment can be taken, and the cooling capacity is further increased. Rise.
[0009]
[Third Embodiment]
FIG. 4 is a diagram showing a permanent magnet array according to the third embodiment. The permanent magnet having the shape of FIG. 3 is divided into two permanent magnets divided into two as shown in 2 ″ of FIG. The combination is a feature.
As the shape of each permanent magnet, a shape in which the tip is convex, concave, or curved is effective.
However, as shown in FIG. 5A, it is advantageous to form a six- section cross section formed by cutting one corner of a base plate-shaped pentagon so as to effectively increase the cooling space.
Manufacturing a permanent magnet 2 'having a shape as shown in FIG. 3 requires a number of processes and takes time and labor. However, if the two-segment method is used in this way, the manufacturing of the permanent magnet is simplified. As shown in (a), a magnet similar to that shown in FIG.
Accordingly, when a plurality of magnets 2 ″ having such a shape are arranged as shown in FIG. 4A, a large space is formed between adjacent magnets 2 ″, so that the cooling space 7 ′ can be increased and the cooling capacity is increased.
In addition, by dividing the permanent magnet into two parts, the permanent magnets can be attracted to each other and prevented from falling off the permanent magnet insertion groove.
[0010]
[Fourth Embodiment]
The permanent magnet array according to the fourth embodiment is characterized in that a coolant is allowed to flow in such a cooling space 7. As the refrigerant, forced air-cooled air, liquid-cooled water, ammonia, or the like is used. In this way, a significant cooling effect can be obtained as compared with natural convection by air.
[0011]
【The invention's effect】
As described above, according to the permanent magnet array for linear motor according to claim 1,
In a permanent magnet array for a linear motor in which a plurality of permanent magnets having different polarities are arranged side by side at regular intervals, and the permanent magnets are surrounded by a permanent magnet holder, the permanent magnets are adjacent to each other. has a recess in the center side among -S pole, is provided with a cooling space in a recess thereof, is composed of a magnet the permanent magnet is divided into two mutually Rutotomoni, of the permanent magnets said divided into two mutually The shape is characterized in that the tip has a convex shape, a concave shape, or a curved shape.
By providing the cooling space between the permanent magnets in this manner, the performance of the motor is improved, the heat conduction to the load can be kept low, the cooling space can be widened, and the manufacture becomes easy.
According to a second aspect of the present invention, in the permanent magnet array for a linear motor according to the first aspect, the shape of each permanent magnet has a hexagonal cross section of a base plate shape. Magnet array.
By doing so, it is advantageous that the cooling space can be effectively made large.
The invention of a linear motor according to claim 3 has the permanent magnet array for linear motor according to claim 1 or 2, and the armature provided on both sides of the permanent magnet array for linear motor. And
A linear motor with good performance can be obtained by using a stator having a cooling space between such permanent magnets.
[Brief description of the drawings]
FIG. 1 is a front view of a linear motor according to the present invention.
2A and 2B are views for explaining a stator according to a first embodiment, in which FIG. 2A is a cross-sectional view taken along line BB of FIG. 1 and FIG. 2B is a perspective view of a permanent magnet alone;
3A and 3B are diagrams showing a permanent magnet array according to a second embodiment, in which FIG. 3A is a cross-sectional view, and FIG. 3B is a perspective view of a permanent magnet alone.
4A and 4B are diagrams showing a permanent magnet array according to a third embodiment, where FIG. 4A is a cross-sectional view, and FIG. 4B is a perspective view of a permanent magnet alone.
FIG. 5 is a view showing the front of a conventional linear motor.
6A and 6B are diagrams for explaining a conventional stator structure, where FIG. 6A is a cross-sectional view taken along line AA in FIG. 5, FIG. 6B is a cross-sectional view taken along line BB in FIG. It is a perspective view of the permanent magnet simple substance 2 which is.
[Explanation of symbols]
1: Stator 2, 2 ', 2 ": Permanent magnet 2a: Depression 3: Movable element 4: Linear motion bearing 5: Length measuring system head 6: Length measuring system scale 7, 7': Cooling space 8 Slider 9 Guide Rail 10: Permanent magnet holder

Claims (3)

In the permanent magnet array for a linear motor, in which a plurality of permanent magnets having different polarities are alternately arranged side by side at regular intervals, and the permanent magnet is surrounded by a permanent magnet holder,
The permanent magnet has a depression in the central side surface between the adjacent NS magnetic poles, and a cooling space is provided in the depression;
Rutotomoni consists magnet the permanent magnet is divided into two mutually shape of each permanent magnet divided into two parts to each other, and wherein the tip is configured in a shape in which the convex or concave or curved shape Permanent magnet array for linear motor. 2. The permanent magnet array for a linear motor according to claim 1, wherein each permanent magnet has a base plate-shaped hexagonal cross section. A linear motor comprising the permanent magnet array for a linear motor according to claim 1 and an armature provided on both sides of the permanent magnet array for the linear motor.

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