JP3941314B2 - Coreless linear motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a coreless linear motor that can be used as a constant speed feed or a high speed positioning feed in the field of, for example, a semiconductor manufacturing apparatus or a machine tool and can reduce thrust ripple, yawing and pitching of a mover.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a coreless linear motor having an armature coil arranged without overlapping concentrated coil groups is as shown in FIGS. 10 to 12 (for example, US Pat. No. 4,151,447).
FIG. 10 shows a conventional coreless linear motor, where (a) is a front sectional view as seen from the moving direction of the mover, and (b) is a plan view of the coreless linear motor with the armature mounting plate removed as seen from above. FIG. FIG. 11 is a side view showing the arrangement relationship of the armature coils, and FIG. 12 shows the phase bands of the armature coils.
In FIG. 10, 21 is a coreless linear motor, 22 is a stator, 23 is a field yoke, 24 is a permanent magnet, 25 is a mover, 26 is an armature, 27 is an armature coil, 28 is a field yoke fixing plate, 29 is an armature mounting plate, and 30 is a resin mold.
The stator 22 is arranged with two field yokes 23 fixed opposite to each other in the longitudinal direction thereof via a field yoke fixing plate 28, and alternately having different polarities along the inside of the field yoke 23. It is composed of a plurality of permanent magnets 24. The permanent magnets 24 are arranged such that adjacent magnets are arranged at every Pm pitch, and the magnets facing each other with the armature 26 interposed therebetween have different polarities.
The mover 25 is composed of a coreless armature 26 disposed so as to be sandwiched between a row of permanent magnets 24 via a magnetic gap, and the armature 26 includes a plurality of coil groups that are concentratedly wound. Is fixed by a resin mold 30 and has an armature coil 27 formed into a flat plate shape. At the upper end of the armature portion 26, an armature mounting plate 29 for fixing a table for placing a load (not shown) is provided.
Among them, the armature coil 27 has six concentrated winding coils arranged in the traveling direction as shown in FIG. 10 (b) and has a three-phase three-coil four-pole structure. It is 4/3 × Pm. As shown in FIG. 11, the six coils are arranged in the order of the U-phase coil, the W-phase coil, and the V-phase coil from the left, and the shape of this concentrated winding armature coil 27 is the main facing the permanent magnet 24. The two coil sides that generate thrust are parallel to each other.
When such a coreless linear motor 21 passes a predetermined current according to the position of the armature 26 through the armature coil 27 arranged without overlapping the coil group of concentrated winding, the armature coil 27, the permanent magnet 24, Due to the electromagnetic action, the mover 25 moves linearly.
[0003]
[Problems to be solved by the invention]
However, in the prior art coreless linear motor, as shown in FIG. 12, there is a case of only one phase in a phase band facing one permanent magnet. In FIG. 12, each phase band of U phase and V phase faces one permanent magnet. For example, in the process of assembling the linear motor, when the plurality of armature coils cannot be accurately arranged in the traveling direction of the linear motor and a positional deviation occurs, when the assembled linear motor is driven There is a problem that thrust ripple corresponding to the absolute value of the current flowing through the coil is generated. Similarly, when the permanent magnet is attached in the traveling direction of the linear motor, a large thrust ripple is generated when a displacement occurs during the attachment.
Furthermore, it is easily affected by the dimensional accuracy of the armature coil alone, and it is difficult to reduce the thrust ripple.
The present invention has been made to solve the above-described problem, and provides a coreless linear motor capable of reducing thrust ripple without being affected by misalignment due to mounting errors of an armature coil or a permanent magnet. With the goal.
[0004]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention of claim 1 is directed to a field yoke in which a plurality of permanent magnets having different polarities are alternately arranged side by side, and opposed to the magnet array of the permanent magnets via a magnetic gap. A coreless armature having an armature coil formed by fixing a plurality of coil groups that are concentrated and fixed by a resin mold and formed into a flat plate shape, the field yoke and the In a coreless linear motor in which either one of the armatures is a stator and the other is a mover, and the field yoke and the armature travel relatively, the armature coil is configured in three phases. At least two coil rows and arranged in parallel with the magnet rows of the permanent magnets in the advancing direction of the armature to insulate the coils between the plurality of coil rows and perform a connection process. The plurality of coil arrays are arranged so as to be shifted by Pm / 3 × n, where Pm is a magnetic pole pitch of the permanent magnet and n is an integer.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
1A and 1B show a coreless linear motor according to a first embodiment of the present invention, in which FIG. 1A is a front sectional view seen from the moving direction of a mover, and FIG. 1B is a coreless with an armature mounting plate removed. It is the top view which looked at the linear motor from the upper part. 2 is a side view in which the armature coils of FIG. 1 are arranged and developed for each coil row, comparing the arrangement relation of the coil rows, and FIG. 3 showing the phase band of the armature coil of FIG. .
In the figure, 1 is a coreless linear motor, 2 is a stator, 3 is a field yoke, 4 is a permanent magnet, 5 is a mover, 6 is an armature, 7 is an armature coil, 8 is a field yoke fixing plate, 9 Is an armature mounting plate, and 10 is a resin mold. The coreless linear motor 1 according to this embodiment is an example of a magnetic flux penetrating type in which the field yoke 3 is on both sides of the armature 6, and is based on the prior art in that it has a three-phase three-coil four-pole structure. Is the same.
The differences between the present invention and the conventional one will be described below.
The armature coil 7 is arranged in parallel with the row of the permanent magnets 4 in the traveling direction of the armature 6, and is provided with three coil rows, that is, a first coil row 7A, a second coil row 7B, and a third coil row. 7C, and a substrate 11 for coil insulation and connection processing is inserted between the three coil rows 7A, 7B, 7C, and the armature coil 7 and the entire substrate 11 are made of resin mold 10 It is fixed.
In addition, when the magnetic pole pitch of the permanent magnet 4 is Pm and the integer is n, the first coil array 7A and the second coil array 7B among the three armature coils have an electrical angle of 60 ° (= Pm). / 3) is shifted by a distance. The second coil array 7B and the third coil array 7C are also arranged with an electrical angle shifted by 60 ° (= Pm / 3).
Specifically, a plurality of coil groups are arranged in the order of U phase, W phase, and V phase from the left in the first coil row 7A. Further, since the second coil group 7B is displaced by 60 ° in terms of electrical angle with respect to the first coil group 7A, a plurality of coil groups are arranged in the order of W phase, V phase, and U phase. The direction of the winding start and the winding end is changed so as to reverse. Since the third coil array 7C is displaced by 120 ° in electrical angle with respect to the first coil array 7A, a plurality of coil groups are arranged in the order of V phase, U phase, and W phase. Here, the pitch of the coil is Pm × 4/3.
In the first embodiment, in such a configuration, when the phase band of the coil is divided for each magnetic pole pitch as shown in FIG. 3, all the phase bands (U phase, V phase, W phase) are one permanent. The magnetic pole pitch Pm of the magnet enters and opposes. Therefore, for example, in the process of assembling the linear motor, even if the coil array that constitutes the armature coil cannot be accurately arranged in the traveling direction of the linear motor, the positional deviation may occur, or the permanent magnet Even if not arranged accurately, the coils of each phase are opposed to the individual permanent magnets, so that the generation of thrust ripple can be reduced when the linear motor is driven. In addition, a margin can be given to the dimensional accuracy of the single coil.
[0006]
Next, a second embodiment of the present invention will be described.
4A and 4B show a coreless linear motor according to a second embodiment of the present invention, in which FIG. 4A is a front sectional view seen from the moving direction of the mover, and FIG. 4B is a coreless with the armature mounting plate removed. It is the top view which looked at the linear motor from the upper part. FIG. 5 is a side view in which the armature coils of FIG. 4 are arranged and developed for each coil row, comparing the arrangement relation of the coil rows, and FIG. 6 shows the phase band of the armature coil of FIG. . In addition, this embodiment has a basic configuration of two-phase four-coil six poles, and a substrate for coil insulation and connection processing is inserted between the armature coils, and the armature coil and the entire substrate are fixed with a resin mold. The construction to be performed is the same as that of the first embodiment.
The second embodiment is different from the first embodiment in that the armature coil 12 is arranged in parallel with the row of permanent magnets 4 in the traveling direction of the armature 6, and two coil rows, that is, the first 1 coil row 12A and second coil row 12B, and when the magnetic pole pitch of the permanent magnet 4 is Pm and the integer is n, among the three armature coils, the first coil row 12A And the second coil array 12B are arranged with an electrical angle shifted by 90 ° (= Pm / 2).
Specifically, a plurality of coil groups are arranged in the order of A phase, B phase, A phase, and B phase from the left in the first coil row 12A, and the winding direction of the two coils in each phase is reversed. Connected. Further, since the second coil group 12B is shifted from the first coil group 12A by an electrical angle of just 90 °, the coils are arranged in the order of B phase, A phase, B phase, and A phase. Two coils are connected so that the winding direction is reversed. Here, the pitch of the coil is Pm × 3/2.
In the second embodiment, in such a configuration, when the phase band of the coil is divided for each magnetic pole pitch as shown in FIG. 6, all the phase bands (A phase and B phase) are magnetic poles of one permanent magnet. Entering the pitch Pm and facing each other. Therefore, for example, in the process of assembling the linear motor, even if the coil array that constitutes the armature coil cannot be accurately arranged in the traveling direction of the linear motor, the positional deviation may occur, or the permanent magnet Even if it is not accurately arranged, the same effect as in the second embodiment can be obtained.
[0007]
Next, a third embodiment of the present invention will be described.
7A and 7B show a coreless linear motor according to a third embodiment of the present invention, in which FIG. 7A is a front sectional view seen from the moving direction of the mover, and FIG. 7B is a coreless with the armature mounting plate removed. It is the top view which looked at the linear motor from the upper part. FIG. 8 is a side view in which the armature coils of FIG. 7 are arranged and developed for each coil row, comparing the arrangement relationship of the coil rows, and FIG. 9 shows the phase band of the armature coil of FIG. . The present embodiment has a two-phase coil as a basic configuration, and a configuration in which a substrate for coil insulation and connection processing is inserted between the armature coils, and the armature coil and the entire substrate are fixed by a resin mold. This is the same as the second embodiment.
The third embodiment is different from the second embodiment in that the armature coil 13 is arranged in parallel with the row of permanent magnets 4 in the traveling direction of the armature 6, and two coil rows, that is, the first 1 coil array 13A and 2nd coil array 13B, and when the magnetic pole pitch of the permanent magnet 4 is Pm and the integer is n, the first coil of the two armature coils The row 13A and the second coil row 13B are arranged with an electrical angle shifted by 90 ° (= Pm / 2).
Specifically, all the A-phase coil groups are arranged in the first coil array 13A, and all the B-phase coil groups are arranged in the second coil array 13B. Here, the pitch of the coil is exactly 2 × Pm.
Furthermore, since each coil layer is composed of one phase, insulation is facilitated, an armature part can be easily configured, and a linear motor that can withstand high voltage specifications can be configured.
In the third embodiment, in such a configuration, when the phase band of the coil is divided for each magnetic pole pitch as shown in FIG. 9, all the phase bands (A phase and B phase) are magnetic poles of one permanent magnet. Entering the pitch Pm and facing each other. Therefore, for example, in the process of assembling the linear motor, even if the coil array that constitutes the armature coil cannot be accurately arranged in the traveling direction of the linear motor, the positional deviation may occur, or the permanent magnet Even if they are not accurately arranged, the same effects as those of the first and second embodiments can be obtained.
Note that the substrate on which the coil array connection processing is performed may be a printed circuit board on which the connection is patterned.
Moreover, in each Example, the example of the coreless linear motor of the magnetic flux penetration type structure which has a field yoke on both sides of an armature was shown, but it is equivalent to the structure cut in half from the axis target position of the magnetic flux penetration type structure, A so-called gap facing type may be used.
In each embodiment, an example of a coreless linear motor having an armature as a mover and a field yoke as a stator has been shown. However, the present invention is not limited to this configuration, and the field yoke is used as a mover and the armature is fixed. You may make it the structure made into a child.
In addition, the linear motor according to the present embodiment has been described with an example of a two-phase two-coil configuration and a three-phase three-coil configuration, but is limited to such combinations of the number of phases and the number of coil sequences. However, it may be selected appropriately.
[0008]
【The invention's effect】
As described above, according to the embodiment of the present invention, the coreless linear motor is configured such that a plurality of concentrated coil coils are arranged so as to be shifted from each other. Since the permanent magnets enter and face each other within the magnetic pole pitch Pm, the coil array constituting the armature coil cannot be accurately arranged in the traveling direction of the linear motor in the process of assembling the linear motor. Even if the permanent magnet is not accurately arranged, the generation of thrust ripple can be reduced when the linear motor is driven. In addition, since the dimensional accuracy of the single coil can be afforded, the cost can be reduced.
Furthermore, since this coreless linear motor can reduce generation | occurrence | production of thrust ripple as mentioned above, it can implement | achieve constant speed feed and high-speed positioning.
[Brief description of the drawings]
FIG. 1 shows a coreless linear motor according to a first embodiment of the present invention, in which (a) is a front sectional view as seen from a moving direction of a mover, and (b) is a state with an armature mounting plate removed. It is the top view which looked at the coreless linear motor from the upper part.
FIG. 2 is a side view in which the armature coils of FIG. 1 are arranged and developed for each coil array, and the arrangement relation of the coil arrays is compared.
FIG. 3 shows a phase band of the armature coil of FIG. 2;
FIGS. 4A and 4B show a coreless linear motor according to a second embodiment of the present invention, in which FIG. 4A is a front sectional view seen from the moving direction of the mover, and FIG. 4B is a state where an armature mounting plate is removed; It is the top view which looked at the coreless linear motor from the upper part.
5 is a side view in which the armature coils of FIG. 4 are arranged and developed for each coil array, and the arrangement relation of the coil arrays is compared. FIG.
6 shows a phase band of the armature coil of FIG.
7A and 7B show a coreless linear motor according to a third embodiment of the present invention, in which FIG. 7A is a front sectional view as seen from the moving direction of the mover, and FIG. It is the top view which looked at the coreless linear motor from the upper part.
8 is a side view in which the armature coils in FIG. 7 are arranged and developed for each coil array, and the arrangement relation of the coil arrays is compared. FIG.
9 shows a phase band of the armature coil of FIG.
FIGS. 10A and 10B are a conventional coreless linear motor, wherein FIG. 10A is a front cross-sectional view seen from the moving direction of the mover, and FIG. 10B is a top view of the coreless linear motor with the armature mounting plate removed. It is a top view.
11 is a side view showing an arrangement relationship for each armature coil in FIG. 10;
12 shows a phase band of the armature coil of FIG.
[Explanation of symbols]
1: coreless linear motor 2: stator 3: field yoke 4: permanent magnet 5: mover 6: armature 7: armature coil 7A: first coil row 7B: second coil row 7C: third Coil array 8: Field yoke fixing plate 9: Armature mounting plate 10: Resin mold 11: Substrate 12: Armature coil 12A: First coil array 12B: Second coil array 13: Armature coil 13A: First Coil array 13B: second coil array

Claims (1)

A field yoke in which a plurality of permanent magnets having different polarities are alternately arranged next to each other, and a magnet group of the permanent magnets and a magnetic gap are arranged to face each other, and a plurality of coil groups having concentrated windings are made of resin. A coreless armature having an armature coil that is fixed by a mold and formed into a flat plate shape, and one of the field yoke and the armature is a stator and the other is a mover , In a coreless linear motor configured to travel relative to the field yoke and the armature,
The armature coil has at least two coil arrays configured in three phases and is arranged in parallel with the magnet array of the permanent magnets in the advancing direction of the armature,
Insulating the coil between the plurality of coil arrays and placing the substrate subjected to the connection process is arranged,
A coreless linear motor, wherein a plurality of coil arrays are shifted from each other by Pm / 3 × n, where Pm is a magnetic pole pitch of the permanent magnet and n is an integer.

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