JP5029830B2 - Linear motor and table feeding device having the same - Google Patents

Description

  The present invention relates to a high-precision linear motor used, for example, in a semiconductor-related device or a feed device for positioning a machine tool, and more particularly to a linear motor characterized by an armature mounting structure and a cooling structure. The present invention relates to a table feeder provided with

FIG. 7 is a front sectional view of a magnetic attraction force canceling linear motor showing the prior art. FIG. 8 is a side view of the linear motor armature as viewed in the direction of arrow B in FIG. 7, and a part of the side view is broken along the line AA, and the core mounting plate and the armature are mounted. It mainly shows the structure of the connecting portion with the plate and the structure of the two-stage cooling passages provided in both members. FIG. 9 is a side view of the linear motor as viewed in the direction of arrow B in FIG. 7, and is a perspective view centering on a configuration in which both the core mounting plate and the core block are fixed with bolt screws. The conventional example will be described using an example of a moving coil type linear motor that forms a magnetic flux penetrating structure in which field poles are arranged on both sides of an armature.
In FIG. 7, 1 is a field pole and 2 is an armature.
The field pole 1 is made of a flat magnetic material, and is composed of two field yokes 1a arranged opposite to each other with a space therebetween, and a plurality of permanent magnets 1b arranged along the field yoke 1a and having different magnetic poles alternately. It is configured.
The armature 2 is provided facing the permanent magnet 1b through a magnetic gap, punched out from a magnetic steel sheet in a substantially I shape, and formed with slots 3a and concave and convex engaging portions 3b on both side surfaces. And a plurality of core blocks 3 in a straight line direction. The core block 3 includes a core block 3 in which the armature iron plates are stacked in the vertical direction; They are arranged side by side, and the engaging portions 3b of the core block 3 are engaged with each other to be integrated with a resin mold (not shown).
In addition, core mounting plates 10 and 10 ′ for fixing the core block are provided at both upper and lower ends in the stacking direction of the core block 3 constituting the armature 2. An armature mounting plate 20 for mounting a table that is not to be mounted is provided. The core block 3 is sandwiched between the core mounting plates 10 and 10 'and fixed by a bolt screw 30, and is integrated by a resin mold. The armature 2 is designed to freely design the thrust generated by the linear motor by changing the number of laminated steel plates constituting the core block 3 to change the stacking thickness or by increasing or decreasing the number of the core blocks 3. Yes.

Further, both the core mounting plate 10 and the armature mounting plate 20 are provided with cooling passages so that the heat generated in the armature 2 can be efficiently dissipated and cooled to obtain highly accurate positioning control characteristics. The cooling structure is adopted. Specifically, as shown in FIGS. 7 and 8, 11 is a core mounting plate cooling passage, 11a is an inlet of the core mounting plate cooling passage, 11b is an outlet of the core mounting plate cooling passage, and 21 is an armature mounting plate. Cooling passage, 21a is an inlet of the armature mounting plate cooling passage, 21b is an outlet of the armature mounting plate cooling passage, 31 is a bolt screw for fixing the armature mounting plate, 33 is a core mounting plate cooling passage outlet 11b and the armature mounting plate This is a joint for coupling the cooling passage inlet 21a.
In such a configuration, when the armature winding 4 of the linear motor is energized, the armature 2 to which the core block 3 is attached moves in the linear direction by the electromagnetic action of the magnetic flux of the armature winding 4 and the permanent magnet 1b. . At this time, when the refrigerant flows through the core attachment plate cooling passage 11 provided inside the core attachment plate 10, the refrigerant is returned to the armature attachment plate 20 via the joint 33, so that the heat generated by the armature is heat-exchanged by the refrigerant. (See, for example, Patent Document 1 and Patent Document 2).
JP 11-27927 A JP 2000-217334 A

However, the prior art has the following problems.
(1) As described above, the core block of the armature is configured by laminating a plurality of electromagnetic steel plates, but if the laminated electromagnetic steel plate has a thickness variation, the configured armature core block is in the height direction. It produces high and low variations. Since the upper and lower core mounting plates that are fixed by sandwiching the core block from the upper and lower ends in the height direction of the armature are each integrated, a plurality of armature core blocks with high and low variations are fixed uniformly with screws. It is difficult. Also, when casting the armature with mold resin, the core block that has a gap with the core mounting plate due to external force such as pressure of the casting resin or stress caused by temperature change will collapse or position Deviation occurs. A so-called core block pitch shift occurs, which causes cogging thrust and thrust ripple, which in turn causes deterioration of the contouring performance or positioning performance of machine tools and semiconductor devices incorporating linear motors. It was.
(2) Also, the cooling passages provided in the core mounting plate and the armature mounting plate are configured to be installed through metal (such as copper) cooling pipes in through holes provided in the core mounting plate and the armature mounting plate, respectively. There is a problem that the cooling performance is deteriorated due to the existence of a gap between the through hole and the metal cooling pipe.
(3) Since the cooling passage (two-stage cooling passage) is installed together with the core mounting plate and the armature mounting plate, the thickness of the core mounting plate and the armature mounting plate is required so that the height of the armature can be reduced. It was to increase.
(4) Further, in order to connect the core mounting plate cooling passage outlet and the armature mounting plate cooling passage inlet, the length of the armature is increased by the presence of a joint as a connecting part. That is, there is a problem that the effective dimension of the armature coil is reduced.
The present invention has been made to solve the above-described problems, and reduces the generation of cogging thrust as much as possible without causing a pitch shift of the armature core, and also improves the cooling performance without increasing the generation loss of the motor. It is an object of the present invention to provide a highly accurate linear motor that can be improved and capable of suppressing an increase in the size of a motor armature and a table feeding device including the same.

In order to solve the above-mentioned problem, the invention relating to the linear motor according to claim 1 is arranged such that a plurality of permanent magnets having different magnetic poles are arranged side by side in a straight line on a two-row flat field yoke. A field pole, and an armature disposed between the field poles so as to face a magnet array of the permanent magnet via a magnetic gap, and the armature is punched in a substantially I shape from an electromagnetic steel sheet, A core block in which a plurality of armature iron plates formed with slots and concave and convex engaging portions are formed on both side surfaces, and an armature winding in which coils are accommodated in aligned slots in the slots of the core block A plurality of the core blocks are arranged in a linear direction, and engaging portions of the core blocks are engaged with each other, and either the field pole or the armature is used as a stator, and the other is used as a mover. As said field pole In the linear motor configured to travel relatively with the armature, the core block is the same as the core block so that each of the plurality of core blocks is individually fixed to the upper and lower ends in the stacking direction of the core blocks. A plurality of first core mounting plates divided into the number are provided, and at least the first core mounting plate has at least the same length as the total length of the plurality of core blocks connected so as to fix the plurality of core blocks together. A second core mounting plate is provided, and each core block is fixed by screwing with a bolt screw from the first core mounting plate side toward the second core mounting plate, and is integrally configured by a resin mold. It is characterized by.
According to a second aspect of the present invention, there is provided the linear motor according to the first aspect, wherein the first armature mounting is provided on a side opposite to the surface of the first core mounting plate and the second core mounting plate facing the core block. A plate, a second armature mounting plate, and between the first core mounting plate and the first armature mounting plate and between the second core mounting plate and the second armature mounting plate, respectively. A cooling passage is provided.
According to a third aspect of the present invention, in the linear motor according to the second aspect, the cooling passage includes a groove formed on the armature mounting plate side, and a metal cooling pipe embedded in the groove. In addition, it is characterized by being continuously folded in the traveling direction.
The invention of claim 4 is, in the linear motor according to claim 2, one of the second armature mounting plate and the first armature mounting plate as a fixed base for attachment to the outside of the table It is characterized by being used for both purposes.
The invention described in claim 5 is characterized in that a table feeding device for positioning and feeding a table using the linear motor described in any one of claims 1 to 4 is provided.

According to the present invention, by fixing each divided core block of the armature at a normal position, the pitch deviation between the armature cores can be reduced as much as possible, and the cogging thrust of the linear motor can be minimized.
As a result, it is possible to provide a machine tool with high contouring performance and high-precision machining, and a linear motor that can perform fine positioning at high speed and can be applied to a high-throughput semiconductor manufacturing apparatus.
According to the present invention, since the cooling pipe is installed only at the interface between the core mounting plate and the armature mounting plate, the thickness dimension of the core mounting plate and the armature mounting plate can be reduced. Technical connection parts (joints) are also unnecessary, and an increase in the size of the motor armature can be suppressed.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected about the same component of this invention as a prior art, the description is abbreviate | omitted, and a different point is demonstrated.

FIG. 1 is a front sectional view of a magnetic attractive force canceling linear motor showing a first embodiment of the present invention.
FIG. 2 is a side view of the linear motor armature as viewed from the direction of arrow B in FIG. 1, and a part of the side view is broken along the line AA, and the core mounting plate and armature mounting It mainly shows the structure of the joint portion with the plate and the structure of the two-stage cooling passage provided in the armature mounting plate. FIG. 3 is a plan view of the linear motor as viewed in the direction of arrow C in FIG. 1, with a part of the plan view broken and a configuration of the coupling portion between the core mounting plate and the core block. It is a thing. FIG. 4 is a side view of the linear motor as viewed from the direction of arrow D in FIG. 3, and is a perspective view centering on a configuration in which both the core mounting plate and the core block are fixed with bolt screws.
1-4, 5a is a first core mounting plate, 5b is a second core mounting plate, 6a is a first armature mounting plate, 6b is a second armature mounting plate, 7 is a cooling passage, 7a is a groove, 7b is a cooling pipe, 30 is a bolt screw, and 31 and 32 are bolt screws.
Further, the first embodiment of the present invention differs from the prior art in that the core block 3 is the same as the core block 3 so that a plurality of core blocks are individually fixed to the upper and lower ends in the stacking direction. A plurality of first core mounting plates 5a divided into a number are provided, and at least the same length as the entire length of the plurality of core blocks connected to each other is fixed to the other. A second core mounting plate 5b is provided, and each core block is fixed by screwing with a bolt screw 30 from the first core mounting plate 5a side toward the second core mounting plate 5b, and is integrally formed by a resin mold. It is a point that was configured.

Next, the operation of the linear motor will be described.
In FIG. 3, when the armature winding 4 is energized, the magnetic flux generated in the armature winding 4 flows along the rolling direction of the core block 3 of the armature, passes through the permanent magnet 1b, and from the field yoke 1a. It flows from the adjacent permanent magnet 1b 'to the core block 3. A mover (not shown) attached to the core block 3 is moved in a linear direction by the electromagnetic action of the magnetic flux generated from the armature winding 4 and flowing into the core block 3 and the magnetic flux of the permanent magnet.
At this time, in the linear motor of the present invention shown in FIG. 2, the split core can be fixed at a properly determined position, so that the armature core does not fall down or be displaced due to mold casting. Generation of cogging thrust is suppressed and thrust ripple can be minimized.

In the first embodiment of the present invention, a plurality of first core mounting plates 5a for individually fixing a plurality of core blocks are provided on one of the upper and lower ends of the core block 3, and the whole of the plurality of core blocks is integrated on the other side. The second core fixing plate is fixed to each other, and the bolt screws 30 are screwed and fixed to both core fixing plates to fix each divided core at a normal position. The pitch deviation can be reduced as much as possible, and the cogging thrust of the linear motor can be minimized.
From the above, there is a great effect that it is possible to provide a machine tool with high contouring performance and capable of high-precision machining, a linear motor that can perform fine positioning at high speed and can be applied to a high-throughput semiconductor manufacturing apparatus.

FIG. 5 is a cross-sectional view of the cooling passage of the linear motor showing the second embodiment of the present invention, and corresponds to an enlarged view of portion E in FIG.
FIG. 6 is a cross-sectional plan view showing a continuously folded shape of the cooling passage along the lines XX and YY in FIG.
The features of the second embodiment are as follows.
A first armature mounting plate 6a and a second armature mounting plate 6b are provided on opposite sides of the first core mounting plate 5a and the second core mounting plate 5b opposite to the surface facing the core block 3, respectively. The cooling passages 7 are provided in the vicinity of the first core mounting plate 5a side of the child mounting plate 6a and in the vicinity of the second core mounting plate 5b side of the second armature mounting plate 6b.
The cooling passage 7 includes a groove 7a formed in each armature mounting plate 6a, 6b and a metal cooling pipe 7b embedded in the groove 7a, and is continuously folded in the traveling direction. Are arranged. The cooling pipe 7b is manufactured in advance by place processing.
Furthermore, one of the first armature mounting plate 6a and the second armature mounting plate 6b is also used as a fixed base for mounting to an external table.

Next, operations related to the cooling structure of the linear motor will be described.
In FIGS. 1, 2, 5, and 6, when a metal cooling pipe is provided in the vicinity of the core mounting plate of the armature mounting plate, and the metal cooling pipe is brought into close contact with the armature mounting plate and the core mounting plate by fastening bolts and screws. In the cross section of the metal cooling pipe manufactured in advance by place processing, a portion in contact with the core mounting plate is deformed flat. Under such a condition, the contact surface between the armature core block formed by winding the armature winding of the heat generation source and the core mounting plate increases, so that the core block, the core mounting plate, the armature mounting plate, The thermal resistance during is reduced. As a result, when the cooling passages are arranged in the armature mounting plates at the upper and lower ends of the armature and the refrigerant flows, the heat generated in the armature winding is heat-exchanged by the refrigerant flowing through the cooling passages, and the cooling performance is improved.

In the second embodiment of the present invention, a metal cooling pipe is provided in the vicinity of the core mounting plate of the armature mounting plate, and the metal cooling pipe is brought into close contact with the armature mounting plate and the core mounting plate by fastening bolts and screws. As a result, the increase in the contact surface between the armature core block and the core mounting plate reduces the thermal resistance between the members, and the refrigerant flowing through the armature mounting plate efficiently heats the armature windings. It can be exchanged and the cooling performance can be improved.
In addition, since the cooling structure is configured so that the cooling pipe is substantially installed only at the interface between the core mounting plate and the armature mounting plate, the thickness dimension of the core mounting plate and the armature mounting plate can be reduced. This is possible and can save space.
Further, in this embodiment, the cooling pipe provided on the armature mounting plate is continuously folded in the traveling direction, so that a cooling passage is provided in each of the core mounting plate and the armature mounting plate as in the prior art. Without the need for connecting parts (joints) for connecting the two-stage cooling passages, it is possible to suppress an increase in the size of the motor armature.
Furthermore, since either one of the first armature mounting plate and the second armature mounting plate is used as a fixed base for mounting the external table, the degree of freedom for mounting the linear motor to the external machine device is increased. , Space can be saved.
Furthermore, the armature core block of the example of the present invention can be constructed by connecting and arranging a plurality of armature core blocks in the running direction, so that it is possible to realize an armature having a long stroke. This is effective in manufacturing the armature core block.

  As described above, the generation of the cogging thrust is reduced as much as possible without causing the pitch deviation of the armature core, the cooling performance is improved without increasing the generation loss of the motor, and the motor armature is increased. A high-precision linear motor that can be controlled and a table feed device equipped with the same can be provided, so a machine tool table capable of high-precision machining, a semiconductor manufacturing device that requires high-speed fine positioning and a constant feed speed, and liquid crystal inspection Applicable to devices and the like.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front sectional view of a magnetic attraction force canceling linear motor showing a first embodiment of the present invention. FIG. 2 is a side view of the linear motor armature as viewed from the direction of arrow B in FIG. 1, and a part of the side view is broken along the line AA, and the core mounting plate and the armature mounting plate are coupled. The structure of the part and the structure of the two-stage cooling passage provided in the armature mounting plate are mainly shown. FIG. 2 is a plan view of the linear motor as viewed from the direction of arrow C in FIG. 1, with a part of the plan view broken and a configuration of a coupling portion between the core mounting plate and the core block. . FIG. 4 is a side view of the linear motor as viewed from the direction of arrow D in FIG. 3, and is a perspective view centering on a configuration in which both the core mounting plate and the core block are fixed with bolt screws. It is sectional drawing of the cooling passage of the linear motor which shows 2nd Example of this invention, Comprising: It corresponds to the figure which expanded the E section of FIG. FIG. 3 is a cross-sectional plan view showing a continuously folded shape of a cooling passage along line XX and line YY in FIG. 2. It is a front sectional view of a magnetic attraction force cancellation type linear motor showing the prior art. FIG. 8 is a side view of the linear motor armature as viewed from the direction of arrow B in FIG. 7, and a part of the side view is broken along the line AA, and the core mounting plate and the armature mounting plate are joined together The configuration of the part and the configuration of the two-stage cooling passage provided in both members are mainly shown. It is the side view of the linear motor which looked at FIG. 7 from the arrow B direction, Comprising: It sees through centering on the structure which fixes both a core attachment board and a core block with a volt | bolt screw.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Field pole 1a Field yoke 1b Permanent magnet 2 Armature 3 Core block 3a Slot 3b Engagement part 4 Armature winding 5a 1st core mounting plate 5b 2nd core mounting plate 6a 1st armature mounting plate 6b 2nd electric machine Sub-mounting plate 7 Cooling passage 7a Groove 7b Cooling pipe 30 Bolt screws 31, 32 Bolt screws

Claims (5)

A field pole in which a plurality of permanent magnets having different magnetic poles are arranged side by side in a straight line on a flat field yoke formed of two rows;
An armature disposed between the field poles so as to face the magnet row of the permanent magnets through a magnetic gap, and
The armature is punched into a substantially I shape from a magnetic steel sheet, and a core block in which a plurality of armature iron plates formed by forming slots and concave and convex engaging portions on both sides is laminated, and a coil is formed in the slot of the core block. Including a plurality of the core blocks arranged in a linear direction, and engaging portions of the core blocks are engaged with each other.
In the linear motor in which either one of the field pole and the armature is a stator and the other is a mover, and the field pole and the armature are relatively driven,
At the upper and lower ends in the stacking direction of the core blocks, a plurality of first core mounting plates that are divided into the same number as the core blocks are provided on one side so that each of the plurality of core blocks is individually fixed. In addition, a second core mounting plate having at least the same length as the whole length of the plurality of core blocks connected to each other is provided so as to fix the whole of the plurality of core blocks integrally.
A linear motor characterized in that each core block is screwed and fixed with a bolt screw from the first core mounting plate side toward the second core mounting plate and is integrally formed by a resin mold. A first armature mounting plate and a second armature mounting plate are provided on opposite sides of the first core mounting plate and the surface facing the core block in the second core mounting plate, respectively.
The cooling passage is provided in the vicinity of the first core mounting plate side of the first armature mounting plate and in the vicinity of the second core mounting plate side of the second armature mounting plate, respectively. The linear motor described.   The cooling passage is composed of a groove formed on each armature mounting plate side and a metal cooling pipe embedded in the groove, and is continuously folded in the traveling direction. The linear motor according to claim 2. 3. The linear motor according to claim 2, wherein one of the first armature mounting plate and the second armature mounting plate is also used as a fixed base for mounting to an external table. . A table feeding device for positioning and feeding a table using the linear motor according to claim 1.

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