JP3694821B2 - Linear motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a linear motor used for driving a table of a machine tool.
[0002]
[Prior art]
Conventionally, a linear motor used for driving a table or the like has been disclosed, for example, as shown in FIG. 6 (for example, JP-A-5-49230).
That is, the fixed portion 10 is attached to the yoke portion 20 made of a magnetic body having a U-shaped cross section and a predetermined length, and to the inner side surfaces 210a and 220a of the both leg portions 210 and 220 of the yoke portion 20 so as to The permanent magnet 30 comprises a guide rail 40 extending in the longitudinal direction on the upper surfaces of both leg portions 210 and 220 of the yoke portion 20.
The movable portion 50 includes a table 520 supported by a bearing portion 510 so as to move along the longitudinal direction on the guide rail 40, and an armature portion 60 attached to the lower surface of the table 520. .
The armature part 60 is disposed in a space between the leg parts 210 and 220 of the yoke part 20 and is composed of an armature core 610 made of a laminated steel plate facing the permanent magnets 30 via a gap, The armature coil 620 is wound around the core 610.
[0003]
[Problems to be solved by the invention]
However, in the above prior art, since the armature core 530 around which the armature coil 540 that is a heat generation source is wound is directly attached to the table 520, the heat generated by the armature coil 540 is easily transmitted to the table 520, There has been a problem that it is difficult to use in equipment in which the error in positioning accuracy of the table due to the influence of heat, such as semiconductor manufacturing equipment, is a problem.
An object of the present invention is to provide a highly accurate linear motor by reducing heat transmitted from an armature coil to a table.
[0004]
[Means for Solving the Problems]
In order to solve the above problems, the present invention is directed to a flat yoke portion, a plurality of permanent magnets arranged so that different polarities appear alternately in the longitudinal direction of the yoke portion, and the permanent magnets facing each other through a gap. In a linear motor comprising an armature part formed by winding an armature coil around a plurality of armature cores and a table attached to the armature part, the linear motor is provided on a surface of the table facing the armature coil. A cooling plate made of a metal material having high thermal conductivity, comprising a refrigerant conduit through which the refrigerant passes, a plurality of fin portions provided close to each side surface of the armature coil, and a base portion in contact with the refrigerant conduit; It is equipped with.
Moreover, the said cooling plate has the said base part divided | segmented for every said several fin part.
Further, the yoke portion is formed in a U-shape, and the permanent magnet is fixed so as to face the inner sides of both leg portions of the yoke portion.
The yoke portion is formed in a rectangular shape, and the permanent magnet is fixed back to back on both side surfaces of the yoke portion.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.
1 is a front sectional view showing an embodiment of the present invention, FIG. 2 is a side sectional view taken along the line AA, and FIG. 3 is a plan sectional view.
In the figure, reference numeral 1 denotes a fixed portion, a U-shaped cross section of a yoke portion 2 made of a magnetic material, and permanent magnets that are attached to the inner side surfaces 211 and 221 of both leg portions 21 and 22 of the yoke portion 2 to constitute a field magnet. 3 (3a, 3b) and guide rails 4 extending in the longitudinal direction on the upper surfaces of both leg portions 21, 22 of the yoke portion 2.
Reference numeral 5 denotes a movable portion, which is disposed in a space between the table 52 supported by the bearing portion 51 so as to move along the longitudinal direction on the guide rail 4 and the leg portions 21 and 22 of the yoke portion 2. The armature portion 6 is attached to the lower surface of the table 52 with bolts 53.
As shown in FIGS. 2 and 3, the armature portion 6 includes an armature core 61 that faces the permanent magnet 3 via a gap, and an armature coil 62 (62 a, 62 b) wound around the armature core 61. A plurality of unit armatures 6 </ b> X are engaged and formed so as to extend along the longitudinal direction of the guide rail 4.
[0006]
As shown in FIG. 3, the armature core 61 is provided with a recess 611 on one side surface of a rectangular laminated steel sheet and a projection 612 on the opposite side surface, and coil insertion grooves 613a on both side surfaces from both ends. , 613b are stacked.
The armature coil 62a is wound around the coil insertion groove 613a on one end side of the armature core 61, and the armature coil 62b is wound around the coil insertion groove 613b on the other end side.
That is, the armature core 61 is formed by sequentially integrating a plurality of unit armatures 6X by engaging a concave portion 611 of one unit armature 6X and a convex portion 612 of the other unit armature 6X.
[0007]
54 is a cooling groove extending along the longitudinal direction of the guide rail 4 on the surface of the table 52 facing the armature coils 62a and 62b, and 7 is a refrigerant conduit mounted in the cooling groove 54, with openings 71 at both ends. One opening 71 is connected to the refrigerant supply port 551 of the bracket 55 provided at the end of the table 52, and the other opening is connected to the refrigerant discharge port 561 of the bracket 56.
8 is a cooling plate made of copper or aluminum alloy, which is a metal material having high thermal conductivity, and is close to the side surface of each armature coil 62 of the armature portion 6 and is inserted between adjacent armature coils 62. And a base portion 82 inserted between the armature coil 62 and the refrigerant conduit 7. The base portion 82 is fixed in contact with the refrigerant conduit 7. Further, the cooling plate 8 and the armature coil 62 are integrally formed of the mold resin 9.
With such a configuration, the heat generated from the armature coil 62 passes through the cooling plate 8, is transmitted to the refrigerant conduit 7, and is discharged to the outside by the refrigerant flowing in the refrigerant conduit 7. Therefore, heat is not easily transmitted to the table 52, and the temperature rise of the table 52 is reduced.
[0008]
Next, a second embodiment of the present invention will be described.
FIG. 4 is a side sectional view showing a second embodiment of the present invention.
In the first embodiment, the base portion 82 of the cooling plate 8 is integrated with each fin portion 82. In this case, the base portion 82 of the cooling plate 8 is divided for each fin portion 81.
Therefore, when the cooling plate 8 is inserted after the armature core 61 and the armature coil 62 are molded with the molding resin 9, the insertion operation is facilitated.
In this case, an insertion hole for inserting the cooling plate 8 is formed by a jig or the like at the time of molding.
[0009]
Next, a third embodiment of the present invention will be described.
FIG. 5 is a front sectional view showing a third embodiment of the present invention.
In this case, the permanent magnets 3a and 3b are attached back to back on both side surfaces of one rectangular yoke portion 2, and the armature core 61 is divided into 61a and 61b, which are opposed to the permanent magnets 3a and 3b through a gap, respectively. The armature coils 61a and 61b are wound around the armature cores 61a and 61b, respectively.
The configuration of the cooling plate 8 and the configuration of the refrigerant conduit 7 are the same as those in the first and second embodiments.
Therefore, the heat generated from the armature coil 62 is transmitted to the refrigerant conduit 7 through the cooling plate 8 and discharged to the outside by the refrigerant flowing in the refrigerant conduit 7, and the temperature rise of the table 52 is reduced.
Also, the attractive force acting on the two permanent magnets 3a, 3b and the armature cores 61a, 61b works in the opposite direction with respect to one yoke part 2, that is, works in the direction of canceling each other on the yoke part 2. Even if the rigidity of the yoke portion 2 is low, it does not deform.
[0010]
【The invention's effect】
As described above, according to the present invention, the thermal conductivity of the refrigerant conduit that passes the refrigerant through the table, the fin portion provided close to the side surface of the armature coil, and the base portion that is in contact with the refrigerant conduit. Since the high cooling plate is provided, the heat generated from the armature coil passes through the cooling plate and is discharged to the outside by the refrigerant flowing through the refrigerant conduit.
Therefore, it is difficult for heat to be transmitted to the table 52, the temperature rise of the table 52 is reduced, the error in the positioning accuracy of the table due to the heat effect can be suppressed small, and there is an effect that a highly accurate linear motor can be provided.
[Brief description of the drawings]
FIG. 1 is a front sectional view showing a first embodiment of the present invention.
FIG. 2 is a side sectional view showing a first embodiment of the present invention.
FIG. 3 is a cross-sectional plan view showing a first embodiment of the present invention.
FIG. 4 is a side sectional view showing a second embodiment of the present invention.
FIG. 5 is a front sectional view showing a third embodiment of the present invention.
FIG. 6 is a front sectional view showing a conventional example.
[Explanation of symbols]
1: fixed portion, 2: yoke portion, 21, 22: leg portion, 211: 221: inner surface, 3, 3a, 3b: permanent magnet, 4: guide rail, 5: movable portion, 51: bearing portion, 52: Table, 53: Bolt, 54: Cooling groove, 55, 56: Bracket, 551: Supply port, 561: Discharge port, 6: Armature part, 61, 61a, 61b: Armature core, 611: Recess, 612: Convex part, 62, 62a, 62b: Armature coil, 63a, 63b: Coil insertion groove, 7: Refrigerant conduit, 71: Opening part, 8: Cooling plate, 81: Fin part, 82: Base part, 9: Mold resin

Claims (4)

A plate-shaped yoke portion, a plurality of permanent magnets arranged so that different polarities appear alternately in the longitudinal direction of the yoke portion, and an armature coil on a plurality of armature cores facing the permanent magnet via a gap In a linear motor comprising an armature part formed by winding and a table attached to the armature part,
A refrigerant conduit for passing a refrigerant provided on a surface of the table facing the armature coil, a plurality of fin portions provided in proximity to each side surface of the armature coil, and a base portion in contact with the refrigerant conduit. And a cooling plate made of a metal material having high thermal conductivity. The linear motor according to claim 1, wherein the cooling plate has the base portion divided into the plurality of fin portions. 3. The linear motor according to claim 1, wherein the yoke portion is formed in a U-shape, and the permanent magnet is fixed so as to oppose the inner sides of both leg portions of the yoke portion. The linear motor according to claim 1, wherein the yoke portion is formed in a rectangular shape, and the permanent magnets are fixed back to back on both side surfaces of the yoke portion.

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