JPH10323012A - Linear motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the deformation of the mover of a linear motor which is caused by heat and a magnetic attractive force. SOLUTION: A linear motor consists of a stator 2 having (m)-phase armature windings 24, and a mover 1 which is composed of a mover yoke 11 and a plurality of field permanent magnets 12 which are fixed onto the mover yoke 11 so as to make adjacent poles have polarities different from each other. The mover 1 is supported movably on the stator 2 with a certain gap therebetween. In this construction, a nonmagnetic heat isolation member is provided between the armature windings 24 and the gap.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a movable magnet type linear motor, and particularly to a semiconductor manufacturing apparatus and FA equipment which require high speed and high acceleration / deceleration because they dislike deformation due to thermal deformation or magnetic attraction. Related to a linear motor.

[0002]

2. Description of the Related Art A conventional general movable magnet type linear motor comprises a mover having a field permanent magnet and a stator having an armature core wound. The configuration will be described, for example, with reference to FIG. 5 in the case of a three-phase linear motor having 1/2 the number of slots for each pole and phase. FIG. 5 is a sectional side view of a main part of the linear motor. In FIG. 5, the mover 1
Is constituted by a plate-like movable element yoke 11 extending along the left and right movement directions, and a field permanent magnet 12 fixed to a lower surface of the movable element yoke 11 at a predetermined pole pitch so that polarities are alternately different. The stator 2 includes an armature core 22 including a plurality of iron core teeth 23 and a yoke 21 connecting the iron core teeth 23, an armature winding 24 wound around each iron core tooth 23, a frame 26 accommodating the armature windings 24, and an electric motor. It is made of a mold resin 27 for fixing the child core 22 and the armature winding 24. In such a configuration, the magnetic gap g corresponds to a gap from the tip of the iron core teeth 23 of the stator 2 to the surface of the field permanent magnet 12 of the mover 1.

[0003]

However, the prior art has the following problems. That is, since the tip of the iron core teeth 23 of the stator 2 and the field permanent magnet 12 of the mover 1 face each other via the gap g and are close to each other, there is a large gap between the field permanent magnet 12 and the iron core teeth 23. Magnetic attraction acts and is attracted to each other. This magnitude is about 3 to 5 times the maximum thrust of the linear motor. Accordingly, the frictional force applied to a guide (not shown) that supports the movable element 1 so as to be movable is extremely large, and the life of the guide is significantly reduced. Further, in order to avoid bending of the mover 1 due to the magnetic attraction force, the mover 1 needs to be strengthened. Therefore, the weight of the mover 1 increases and the high acceleration / deceleration motion is not suitable. . further,
Since the heat generated by applying a current to the armature winding 24 is transmitted to the mover 1 through the gap g, the temperature of the mover 1 rises to thermally demagnetize the field permanent magnet 12 or cause thermal deformation. As a result, fine positioning is not easy, resulting in a decrease in positioning accuracy. Further, the cogging force generated by the magnetic attraction between the iron core teeth 23 and the field permanent magnets 12 is also large, which also deteriorates the positioning accuracy of the table. Therefore, the present invention has been made in view of such a problem, and an object of the present invention is to provide a high-performance linear motor that suppresses thrust ripples without increasing the weight of a mover, reduces thermal deformation, and reduces the thrust ripple.

[0004]

In order to solve the above-mentioned problems, the present invention provides a stator having an m-phase armature winding and a plurality of field permanent magnets such that adjacent magnetic poles are different from each other. A mover fixed on a mover yoke, wherein the mover is movably supported with a fixed gap from the stator, wherein the stator faces the mover. A non-magnetic heat isolating member on the surface to be heated, wherein the heat isolating member is a cooling pipe, a heat insulating material, or a part of a heat pipe, The heat radiation fin is fixed to another part of the pipe. Also, the present invention
Adjacent magnetic poles are different from an m-phase air core coil, a stator comprising a magnetic stator yoke provided below the air core coil, and a frame accommodating the air core coil and the stator yoke. And a mover formed by fixing a plurality of field permanent magnets on the mover yoke so as to be poles, wherein the mover is movably supported with a fixed gap from the stator. A non-magnetic cooling pipe having a projection formed on the upper surface of the air-core coil to be inserted into the air-core portion of the air-core coil is provided. With this configuration, heat is thermally insulated between the mover and the stator, so that heat generated in the armature winding of the stator can be prevented from being transmitted to the mover, and the field of the mover can be prevented. Since the distance between the magnetic permanent magnet and the stator core teeth is far away, the magnetic attraction force and cogging force can be reduced.

[0005]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1A and 1B are drawings of a linear motor according to a first embodiment of the present invention. FIG. 1A is a front sectional view of a main part of the linear motor, and FIG. FIG. In the figure, a mover 1 has a planar mover yoke 11 extending in the direction of movement and a predetermined pole pitch on its lower surface so that the polarity is alternately different from that of the conventional example shown in FIG. And the field permanent magnets 12 fixed in this manner. The stator 2 includes an armature core 22 including a plurality of iron teeth 23 and a yoke 21 connecting the iron teeth 23, and each iron tooth 23.
An m-phase armature winding 24, a meandering non-magnetic water cooling pipe 31 provided at the tips of the iron core teeth 23, a frame 26 covering the armature core 22 and the water cooling pipe 31. ,
It is made of a mold resin 27 for fixing the armature core 22 and the armature winding 24. In this case, the distance between the field permanent magnet 12 of the mover 1 and the iron core teeth 23 of the stator 2 is far away, so that the magnetic gap is increased and the magnetic attraction force and cogging force are reduced. In addition, since the thrust is also reduced, it is necessary to increase the current in order to obtain the same thrust, thereby increasing the loss. However, since the water cooling pipe 31 passes through the tip of the iron core teeth 23, , The heat generated in the armature winding 24 is transmitted to the refrigerant flowing therein,
Heat is not transmitted to the mover 1.

Next, a second embodiment will be described with reference to the drawings. 2A and 2B are drawings of a linear motor according to a second embodiment of the present invention, in which FIG. 2A is a front sectional view of a main part of the linear motor, and FIG. FIG. In FIG. 2, the mover 1 has the same configuration as the mover 1 of the first embodiment. The stator 2 includes an armature core 22 including a plurality of iron core teeth 23 and a yoke 21 connecting the iron core teeth 23, and an m-phase armature winding 2 wound around each iron core tooth 23.
4, a heat insulating material 41 provided at the tips of the iron core teeth 23, a water cooling pipe 42 installed on the back of the armature core 22, a frame 26 covering the armature core 22, the water cooling pipe 42, and the heat insulating material 41. , And a mold resin 27 for fixing the armature core 24 and the armature winding 24. By doing so, the field permanent magnets 12 of the mover 1 are similar to the first embodiment.
And the distance between the iron core teeth 23 of the stator 2 are increased, so that the magnetic attraction force and the cogging force are reduced.
Generated by the heat is blocked by the heat insulating material 4 spread over the tips of the iron core teeth 23, so that most of the heat is transmitted to the refrigerant passing through the water cooling pipe 42 on the back of the armature core 22. in this way,
The heat of the stator 2 is not transmitted to the mover 1.

Next, a third embodiment will be described with reference to the drawings. 3A and 3B are drawings of a linear motor according to a third embodiment of the present invention. FIG. 3A is a front sectional view of a main part of the linear motor, and FIG. FIG. The mover 1 has the same configuration as the mover 1 of the first embodiment. The stator 2 includes an armature core 22 including a plurality of core teeth 23 and a yoke 21 connecting the core teeth 23, an m-phase armature winding 24 wound around each core tooth 23, and a core tooth 23.
A plurality of linear heat pipe evaporators 51 provided at the tip of the armature, a frame 26 covering the armature core 22 and the heat pipe evaporator 51, and the armature core 22 and the armature winding 24 in the frame 26 are fixed. Molding resin 27, a heat pipe condensing part 52 installed outside the frame 26,
And fins 53 integrated therewith. By doing so, the magnetic gap is increased as in the first and second embodiments, so that the magnetic attraction force and cogging force are reduced, and the heat generated in the armature winding 24 of the stator 2 is reduced. ,
After being transmitted to the heat pipe evaporating section 51, the heat flows to the heat pipe condensing section 52 installed outside the frame 26 and is radiated to the atmosphere from the fins 53 around the heat pipe condensing section 52. Therefore, the stator 2
The generated heat is not transmitted to the mover through the air gap as in the first and second embodiments.

Next, a fourth embodiment will be described with reference to the drawings. 4A and 4B are drawings of a linear motor according to a fourth embodiment of the present invention, wherein FIG. 4A is a front sectional view of a main part of the linear motor, and FIG. FIG. The mover 1 has the same configuration as the mover 1 of the first embodiment. The stator 2 includes a stator yoke 25, an air core coil 24b disposed thereon and bonded thereto, a water cooling pipe 61, an air core coil 24b and a stator yoke 25
And the frame 26 that covers the water cooling pipe 61. The water cooling pipe 61 has a rectangular cross section,
A portion facing the groove of the air-core coil 24b is provided with a protruding protrusion, and has a convex portion 62 that fits into the recess of the air-core coil 24b. Therefore, the water cooling pipe 61 has a structure in which not only the air gap surface of the air core coil 24b but also the air core side surface is contacted, and the heat generated in the air core coil 24b is transmitted well to the refrigerant. By doing so, the gap between the mover 1 and the stator yoke 25 is increased as in the first to third embodiments, so that the magnetic attraction force and the cogging force are reduced. Further, since the refrigerant passes between the air core coil 24b and the mover 1,
The heat generated in the air core coil 24b is transmitted to the refrigerant, and the heat is not transmitted to the surface of the mover 1. that's all,
Four embodiments have been described for the movable magnet type linear motor. However, according to the gist of the present invention, application to the movable coil type linear motor does not hinder at all. In the first to third embodiments, the armature winding 24 is wound around the iron core teeth 23. However, as in the fourth embodiment, the air-core coil 24b may be used, or the helical winding armature winding 24 may be used. May be used. Further, in the above-described embodiment, the magnetization direction of the field permanent magnet 12 is set to be perpendicular to the traveling direction of the mover 1, but this magnetization direction is arranged to be parallel to the traveling direction of the mover 1. You may.

[0009]

As described above, according to the present invention,
Since the heat generated in the armature winding of the stator is not transmitted to the mover through the air gap, thermal deformation of the mover, which has been a problem in the past, is eliminated, and the positioning accuracy of the linear motor can be maintained high. it can. Further, the magnetic gap is widened, the magnetic attraction force is reduced, the load on the guide supporting the mover is reduced, and the life can be greatly improved. Furthermore, since the mass of the mover can be reduced, it can be applied to high acceleration / deceleration feed, and there is an effect that the cogging force is reduced and the positioning accuracy is improved.

[Brief description of the drawings]

FIG. 1 is a linear motor according to a first embodiment of the present invention;

FIG. 2 is a linear motor according to a second embodiment of the present invention;

FIG. 3 is a linear motor according to a third embodiment of the present invention;

FIG. 4 is a linear motor according to a fourth embodiment of the present invention;

FIG. 5 is a conventional linear motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mover 11 Mover yoke 12 Field permanent magnet 2 Stator 21 Yoke 22 Armature core 23 Iron core teeth 24 Armature winding 24b Air core coil 25 Stator yoke 26 Frame 27 Mold resin 31, 42, 61 Water cooling piping 41 Heat Insulation Material 51 Heat Pipe Evaporator 52 Heat Pipe Condenser 53 Fin 62 Convex

Claims (5)

[Claims] 1. A stator having an m-phase armature winding, and a mover having a plurality of field permanent magnets fixed on a mover yoke such that adjacent magnetic poles are different from each other. A linear motor in which the mover is movably supported with a fixed gap from the stator, wherein the stator has a nonmagnetic heat isolation member on a surface facing the mover. And a linear motor. 2. The linear motor according to claim 1, wherein the heat isolating member is a cooling pipe. 3. The linear motor according to claim 1, wherein the heat isolating member is a heat insulating material. 4. The heat isolating member is part of a heat pipe.
2. The linear motor according to claim 1, wherein radiation fins are fixed to another part of the heat pipe. 5. A stator comprising an m-phase air-core coil, a magnetic stator yoke provided below the air-core coil, and a frame containing the air-core coil and the stator yoke. And a mover comprising a plurality of field permanent magnets fixed on a mover yoke such that the magnetic poles are different from each other. The mover is movably supported with a fixed gap from the stator. The linear motor according to claim 1, wherein a non-magnetic cooling pipe having a projection inserted into an air core portion of the air core coil is provided on an upper surface of the air core coil.