JPWO2019150718A1 - Linear motor, manufacturing method of linear motor - Google Patents

Abstract

The linear motor 100 includes a mover 50 including a field magnet 52 and a stator 10 including a plurality of coil modules 20 connected in a movable direction of the mover 50. The coil module 20 includes a plurality of coils 26 arranged in a movable direction.

Description

The present invention relates to a linear motor and a method for manufacturing a linear motor.

Linear motors are used to convert electrical energy into linear motion. As a kind of linear motor, there is a moving magnet type linear motor in which a magnet travels along a coil. For example, Patent Document 1 describes a moving magnet type linear slider having an armature coil as a stator and a field magnet as a mover.

International Publication No. 2005/122369

The present inventor has obtained the following recognition about a moving magnet type linear motor (hereinafter, simply referred to as a linear motor).
In many cases, linear motors have different movable strokes of the mover depending on the application. Therefore, for a linear motor, it is necessary to prepare armature coils having different lengths according to a desired movable stroke. That is, in order to support various applications, it is necessary to manufacture armature coils having different lengths for each application.

An armature coil may be manufactured by resin-molding a plurality of coils arranged in the movable direction. In this case, it is uneconomical because it is necessary to prepare molds having different lengths for each application. Further, when the armature coil is particularly long, there is a problem that it is difficult to manufacture with a normal mold or resin molding equipment. From these, the present inventors have recognized that there is room for improvement in the linear motor from the viewpoint of facilitating the manufacture of armature coils.
Such a problem may occur not only in the armature coil manufactured by resin molding but also in the armature coil manufactured by another method.

The present invention has been made in view of such problems, and an object of the present invention is to provide a linear motor that facilitates the manufacture of armature coils.

In order to solve the above problems, a linear motor according to an embodiment of the present invention includes a mover including a field magnet and a stator including a plurality of coil modules connected in a movable direction of the mover. The coil module includes a plurality of coils arranged in a movable direction.

Another aspect of the present invention is a method of manufacturing a linear motor. This method is a method for manufacturing the above-mentioned linear motor, in which a plurality of coils are housed in a case 22, resin is poured into a case containing a plurality of coils to form a coil module, and a plurality of coils are used. This includes arranging the modules in the movable direction and fixing them to the beam member, and electrically connecting the wiring member 34 to the coil 26.

According to the present invention, it is possible to provide a linear motor that facilitates the manufacture of armature coils.

It is a top view which shows the linear motor which concerns on embodiment of this invention. FIG. 1 is a cross-sectional view taken along the line AA of FIG. It is a top view which shows typically the stator of the linear motor of FIG. It is explanatory drawing which outlines the wiring of the stator of FIG. It is a process drawing explaining the manufacturing process of the stator of the linear motor of FIG. It is sectional drawing of the linear motor which concerns on 1st modification. It is sectional drawing of the linear motor which concerns on 2nd modification. It is sectional drawing of the linear motor which concerns on 3rd modification.

Hereinafter, the present invention will be described with reference to each drawing based on a preferred embodiment. In the embodiments and modifications, the same or equivalent components and members are designated by the same reference numerals, and redundant description will be omitted as appropriate. In addition, the dimensions of the members in each drawing are shown enlarged or reduced as appropriate for easy understanding. In addition, some of the members that are not important for explaining the embodiment in each drawing are omitted and displayed.

In the following description, "parallel" and "vertical" include not only completely parallel and vertical, but also cases where they deviate from parallel and vertical within the range of error. In addition, "abbreviation" means that they are the same in an approximate range.
Also, terms including ordinal numbers such as 1st and 2nd are used to describe various components, but this term is used only for the purpose of distinguishing one component from other components. The components are not limited by.
Further, the linear motor includes a motor in which the mover moves on a curved trajectory such as an arc shape, and is not limited to a motor in which the mover moves on a linear trajectory.

[Embodiment]
The linear motor 100 according to the embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a plan view showing a linear motor 100 according to an embodiment. FIG. 2 is a side sectional view of the linear motor 100 along the line AA.

Hereinafter, the description will be mainly based on the XYZ Cartesian coordinate system. The X-axis direction corresponds to the left-right direction of the paper surface in FIG. 1 and corresponds to the direction perpendicular to the paper surface in FIG. The Y-axis direction corresponds to the vertical direction of the paper surface in FIGS. 1 and 2. The Z-axis direction corresponds to the direction perpendicular to the paper surface in FIG. 1 and corresponds to the left-right direction of the paper surface in FIG. The Y-axis direction and the Z-axis direction are orthogonal to the X-axis direction, respectively. The positive directions of the X-axis, the Y-axis, and the Z-axis are defined in the directions of the arrows in each figure, and the negative directions are defined in the directions opposite to the arrows. Further, the positive side of the X-axis may be referred to as the "right side", and the negative side of the X-axis may be referred to as the "left side". Also, the positive side of the Y axis is called the "front side", the negative side of the Y axis is called the "rear side", the positive side of the Z axis is called the "upper side", and the negative side of the Z axis is called the "lower side". is there. The notation in such a direction does not limit the posture in which the linear motor 100 is used, and the linear motor 100 can be used in any posture depending on the application.

(Linear motor)
The linear motor 100 includes a stator 10 and a mover 50. The mover 50 forms a magnetic circuit in the magnetic gap 60. The linear motor 100 functions as an energy conversion mechanism that generates thrust in the movable direction in the stator 10 in the magnetic gap 60. In the embodiment, the movable direction is arranged so as to coincide with the X-axis direction.

(Movable child)
The mover will be described first. The mover 50 includes a pair of field magnets 52, a pair of yokes 54, and a spacer 56. The field magnet 52 and the pair of yokes 54 form a magnetic circuit that forms a field magnetic field in the magnetic gap 60. The magnetic gap 60 is a gap between the pair of field magnets 52.

The pair of yokes 54 are plate-shaped members extending in the X-axis direction and the Y-axis direction and thin in the Z-axis direction. In plan view, the pair of yokes 54 have a substantially rectangular contour having two sides parallel to the X-axis direction and two sides parallel to the Y-axis direction. The pair of yokes 54 are made of various known soft magnetic materials. The pair of yokes 54 are arranged parallel to each other apart from each other in the Z-axis direction.

The spacer 56 is arranged in the upper region between the pair of yokes 54 and maintains the distance between the pair of yokes 54 in the Z-axis direction. The pair of yokes 54 are fixed to the spacer 56 by a fixture 58 (for example, a bolt) through a plurality of through holes provided near the upper end thereof.

The field magnet 52 functions as a source of magnetic flux that forms a field magnetic field in the magnetic gap 60. The field magnet 52 may include one or more magnets. The field magnet 52 may be configured by arranging a plurality of magnets in a Halbach array. A plurality of magnetic poles are provided on the surface of the field magnet 52 at predetermined intervals in the X-axis direction. In the embodiment, a 6-pole magnetic pole is provided. The field magnet 52 may be formed of various known magnet materials. In this example, the field magnet 52 is made of a rare earth magnet material such as NdFeB. The field magnet 52 may be fixed to the yoke 54 by a known means such as adhesion.

(stator)
The stator 10 includes a plurality of coil modules 20 extending in the X-axis direction, a beam member 30, a second beam member 31, and a wiring member 34. The plurality of coil modules 20 are arranged in the X-axis direction, which is the movable direction. The coil module 20 is, for example, a substantially rectangular member having a substantially rectangular shape in a plan view and being thin in the Z-axis direction. In this example, the coil module 20 is arranged so that the long side is along the X-axis direction and the short side is along the Y-axis direction in a plan view.

The coil module 20 includes a coil assembly 24 and a case 22. The coil assembly 24 includes a plurality of coils 26 arranged in the X-axis direction and a connector 36. The plurality of coils 26 are integrated by being wrapped in a resin 24 m. When the case 22 is provided, as an example, the coil assembly 24 is formed by injecting 24 m of resin into the case 22 in which a plurality of coils 26 are arranged. It is not essential to provide the case 22. When the case 22 is not provided, as an example, the coil assembly 24 is formed by insert molding in which a resin 24 m is injected into a mold in which a plurality of coils 26 are arranged. These manufacturing methods are merely examples, and the coil assembly 24 may be formed by various other manufacturing methods.

The coil 26 has two sides parallel to the X-axis direction and two sides parallel to the Y-axis direction, and has a substantially rectangular contour with four corners rounded in an R shape. The coil 26 may have a contour formed by a curved line such as an ellipse as a whole having no sides, or may have contours of various other shapes. The coil 26 may be an iron core coil, but in this example, it is an air core coil. The coil 26 is composed of a wire wound so as to orbit around the Z axis. When a drive current is supplied to the coil 26, the coil 26 functions as an armature coil that generates a magnetic flux in the Z-axis direction and generates a thrust force in the X-axis direction in the field magnet 52.

The connector 36 includes electrodes electrically connected to the leads of the plurality of coils 26. The connector 36 may be connected to lead wires (leading wires) of a plurality of coils 26 before insert molding and may be integrated with the plurality of coils 26 by insert molding. Alternatively, the connector 36 may be connected to the lead wires of the plurality of coils 26 after insert molding. In this case, the lead wire may be directly exposed from the coil 26, and the connector 36 may be connected to the tip of the lead wire.

The case 22 is provided so as to cover the periphery of the coil assembly 24. The case 22 suppresses the outflow of gas generated from the coil 26 and the resin 24 m surrounding the coil 26 to the outside. The case 22 is a rectangular parallelepiped box body composed of a box-shaped case body 22b having five surfaces with an open upper surface and a lid 22c covering the upper surface of the case body 22b. The lid 22c may be fixed to the upper surface of the case body 22b containing the coil assembly 24, for example, by welding. The case 22 may be formed of a metal material such as non-magnetic stainless steel or a non-metal material such as ceramic.

Next, the wiring member 34 will be described. FIG. 3 is a plan view schematically showing the stator 10. FIG. 4 is an explanatory diagram illustrating the wiring of the stator 10. The wiring member 34 functions as a path for supplying a current from the drive circuit 40 to the coil 26. The current from the drive circuit 40 flows through the coil 26 via the wiring member 34, the connector 36, and the lead wire 26b connected to the electrodes of the connector 36. The wiring member 34 is, for example, a wire module or a printed wiring board. In the embodiment, the wiring member 34 is a printed wiring board on which another connector (not shown) for connecting to the connector 36 is mounted. In the embodiment, the wiring member 34 is housed in the passage recess 30b of the beam member 30, which will be described later.

As a method of supplying the drive current to the plurality of coil modules 20, a full excitation method and a partial excitation method can be considered. The total excitation method is a method in which a drive current is supplied to all the coils constituting one phase. The full excitation method is characterized in that wiring is relatively easy. The partial excitation method is a method of selectively supplying a drive current to the coil 26 in the vicinity of the mover 50. The partial excitation method has a feature that wasteful power is small. In the embodiment, a partial excitation method is adopted. As shown in FIG. 4, each coil module 20 is connected to the drive circuit 40 independently of the other modules.

The beam member 30 and the second beam member 31 function as a beam for connecting the plurality of coil modules 20 and imparting desired rigidity to the stator 10. In this example, the beam member 30 and the second beam member 31 are rod-shaped members having a rectangular cross section extending in the X-axis direction. As shown in FIG. 2, the beam member 30 is provided with a passage recess 30b extending in the X-axis direction. The passage recess 30b is a recess in which the coil module 20 side is open and retracts upward. The passage recess 30b accommodates the connector 36 and the wiring member 34. The beam member 30 is arranged so as to be in contact with the upper surface of the coil module 20, and the second beam member 31 is arranged so as to be in contact with the lower surface of the coil module 20. The plurality of coil modules 20 are fixed to the beam member 30 and the second beam member 31 by fixing members 32 such as bolts. The beam member 30 may be formed as a seamless integrated member, or a plurality of members may be integrated. The same applies to the second beam member 31.

Next, the number of coils (hereinafter, simply referred to as the number of coils) of the plurality of coils 26 constituting the coil module 20 will be described. When driving in three phases, the number of coils is preferably an integral multiple of 3. It is not essential that the number of coils is an integral multiple of 3, and the number of coils may be set arbitrarily. That is, the coil module 20 may be composed of a number of coils 26 other than an integral multiple of 3 as needed. In particular, in the case of partial excitation with the moving magnet type, since it is sufficient to excite the coils 26 having an integer number of 3, modularization may be performed with other than the integer number of 3.

In the case of a motor having a long movable stroke, if the number of coils is 3, the number of coil modules increases and the manufacturing cost increases. Therefore, the number of coils is preferably 6. In the case of a motor with a short movable stroke, if the number of coils is 6 or more, the stator may become unnecessarily long, so the number of coils is preferably 3.

If one coil module 20 becomes too long, there is a high possibility that the coil module 20 will warp and come into contact with the mover 50. From this point of view, the number of coils is preferably 6 or less.

Next, an example of the manufacturing process of the linear motor 100 will be described. FIG. 5 is a process diagram illustrating the manufacturing process S80 of the linear motor 100. In particular, the manufacturing process S80 includes steps S82 to S92 for manufacturing the stator 10.

In step S82, an air-core coil 26 is manufactured by winding a wire whose surface is insulated.

In step S84, the plurality of coils 26 are housed in the case body 22b. The connector 36 is attached to a plurality of coils 26 before or after being housed in the case body 22b. In the embodiment, the connector 36 is attached to the coil 26 before being housed in the case body 22b. The connector 36 is integrated with the coil 26 by the resin 24 m poured in the next step.

In step S86, the plurality of coils 26 are integrated by pouring the resin 24m into the case body 22b accommodating the plurality of coils 26 to form the coil assembly 24.
In step S88, the case body 22b containing the coil 26 into which the resin 24 m is poured is covered with the lid 22c.

In step S90, the lid 22c is fixed to the case body 22b by welding, for example. The lid 22c is provided with an opening 22e, and the connector 36 is exposed from the opening 22e with the lid 22c fixed.

In step S92, a plurality of coil modules 20 are arranged in the X-axis direction, the connector 36 is electrically connected to the wiring portion of the wiring member 34, and the beam member 30 and the second beam member 31 are fixed. In this way, the stator 10 is manufactured.

The linear motor 100 is manufactured by inserting the stator 10 manufactured in this manner into the magnetic gap 60 of the mover 50 manufactured separately. This manufacturing process S80 is only an example, and other processes may be added, a part of the process may be changed or deleted, or the order of the processes may be changed.

As shown in FIG. 1, the wall surface of the case 22 is doubly interposed between the coil module 20 and the adjacent coil module 20. Compared with the case without such a wall surface, the outflow of gas from the resin 24 m can be reduced.

The operation of the linear motor 100 configured in this way will be described. When the drive current is supplied from the drive circuit 40 to the coil module 20, the coil module 20 generates a moving magnetic field in the movable direction, and applies a thrust force in the movable direction to the field magnet 52 of the mover 50. The linear motor 100 drives a drive target connected to the mover 50 by this thrust.

The outline of one aspect of the present invention is as follows. The linear motor 100 of an embodiment of the present invention includes a mover 50 including a field magnet 52 and a stator 10 including a plurality of coil modules 20 connected in a movable direction of the mover 50. The coil module 20 includes a plurality of coils 26 arranged in a movable direction.

According to this aspect, when designing by changing the movable stroke of the linear motor 100, it can be dealt with by changing the number of coil modules 20 to be connected, so that the design can be standardized and the design man-hours can be reduced. When manufacturing by changing the movable stroke of the linear motor 100, it can be handled by changing the number of coil modules 20 to be connected, so that the mold, jigs and tools, manufacturing equipment and the like can be shared. Since the coil module 20 can be made to a length suitable for manufacturing, when manufacturing a long linear motor 100, the jigs and tools and the coil module 20 can be easily handled. Further, the work of connecting the coil module 20 can be performed at the site where the linear motor 100 is installed.

The number of coils of the plurality of coils 26 may be an integral multiple of 3. In this case, the possibility that the stator becomes unnecessarily long due to unnecessary coils can be reduced as compared with the case where the number of coils is not an integral multiple of 3.

The number of coils of the plurality of coils 26 may be 6 or less. In this case, since the coil module 20 can be shortened as compared with the case where the number of coils is 7 or more, the possibility that the coil module 20 warps and comes into contact with the mover 50 can be reduced.

The coil module 20 has a connector 36 that includes electrodes electrically connected to the plurality of coils 26. In this case, when connecting the coil module 20, the connector 36 can be easily connected to the wiring portion of the wiring member 34. Further, if the connector is removable, the existing linear motor can be easily disassembled and reused. When changing the stroke of the existing linear motor, the additional coil module 20 can be easily connected. Compared with the case where the existing linear motor is discarded and a new linear motor is installed, the wasted resources can be significantly reduced.

Another aspect of the present invention is a method of manufacturing a linear motor. In this method, a plurality of coils 26 are housed in the case 22, a resin 24 m is poured into the case 22 containing the plurality of coils 26 to form a coil module 20, and a plurality of coil modules 20 are arranged in a movable direction. It includes fixing to the beam member 30 and electrically connecting the wiring member 34 to the coil 26.

According to this aspect, when designing by changing the movable stroke of the linear motor 100, it can be dealt with by changing the number of coil modules 20 to be connected, so that the design can be standardized and the design man-hours can be reduced. When manufacturing by changing the movable stroke of the linear motor 100, it can be handled by changing the number of coil modules 20 to be connected, so that the mold, jigs and tools, manufacturing equipment and the like can be shared.

Forming the coil module 20 may include fixing the lid 22c to the case body 22b into which the resin 24m is poured. In this case, since the lid 22c is fixed to the case body 22b, gas generation from the resin 24m can be suppressed.

The examples of the embodiments of the present invention have been described in detail above. All of the above-described embodiments are merely specific examples for carrying out the present invention. The content of the embodiment does not limit the technical scope of the present invention, and many design changes such as modification, addition, and deletion of components are made without departing from the idea of the invention defined in the claims. Is possible. In the above-described embodiment, the contents capable of such a design change are described with the notations such as "in the embodiment" and "in the embodiment", but there is no such notation. The content is not unacceptable for design changes. Further, the hatching attached to the cross section of the drawing does not limit the material of the object to which the hatching is attached.

Hereinafter, a modified example will be described. In the drawings and description of the modified examples, the same or equivalent components and members as those in the embodiment are designated by the same reference numerals. The description that overlaps with the embodiment will be omitted as appropriate, and the configuration different from the embodiment will be mainly described.

(First modification)
FIG. 6 is a cross-sectional view showing the linear motor 200a according to the first modification, and corresponds to FIG. The linear motor 200a is different from the linear motor 100 in that the second beam member 31 is not provided, and the other configurations are the same. It is not essential to include the second beam member 31.

(Second modification)
In the linear motor 100, an example in which the beam member 30 and the second beam member 31 are not coupled has been described, but the present invention is not limited to this. FIG. 7 is a cross-sectional view showing the linear motor 200b according to the second modification, and corresponds to FIG. The linear motor 200b is different from the linear motor 100 in that the beam member 30B, the second beam member 31B, and the spacer 35 are provided instead of the beam member 30 and the second beam member 31, and the other configurations are the same. is there. The beam member 30B and the second beam member 31B project from the coil module 20 in the negative direction on the Y axis, and a spacer 35 is provided between the projecting portions. The beam member 30B and the second beam member 31B are integrally connected with the spacer 35 interposed therebetween.

In the linear motor 200b, the beam member 30B and the second beam member 31B have an approach portion 30e that enters the magnetic gap 60. The approach portion 30e may be, for example, a plate-like portion extending in the X-axis direction and the Y-axis direction and thin in the Z-axis direction. The approach portion 30e is provided so as to cover all or part of the coil module 20. By having the approach portion 30e, the warp of the coil module 20 can be suppressed. The approach portion 30e can also be applied to the embodiment and other modifications.

(Third modification example)
FIG. 8 is a cross-sectional view showing a linear motor 200c according to a third modification, and corresponds to FIG. The linear motor 200c is different from the linear motor 200b in that the beam member 30B, the second beam member 31B, and the beam member 30C are provided instead of the spacer 35, and the other configurations are the same. The beam member 30C has a shape in which the beam member 30B, the second beam member 31B, and the spacer 35 are seamlessly integrated.

(Fourth modification)
In the embodiment, an example in which the step of manufacturing the coil module 20 and the step of connecting the coil modules 20 are continuously provided has been described, but the present invention is not limited thereto. Further, it is not essential to include the above-mentioned beam member. For example, in the process of manufacturing the coil module 20, the coil module 20 having no beam member may be manufactured. The coil module 20 without the beam member manufactured in this way may be stored according to specifications such as size. In this case, the step of connecting the coil module 20 may be provided in another factory. The coil module 20 having the desired specifications may be transported to another factory, and the coil module 20 may be connected there.

(Other variants)
The linear motor 100 may be configured by combining coil modules 20 having different numbers of coils.
The linear motor 100 may include a linear coil module 20 and a curved coil module.
The pair of yokes 54 and the spacer 56 may be seamlessly integrally formed.
One of the pair of field magnets 52 that sandwich the coil module 20 may not be provided.
Each of the above-described modifications has the same actions and effects as those of the embodiment.

10 ... Stator, 18 ... Coil, 20 ... Coil module, 22 ... Case, 22b ... Case body, 22c ... Lid, 24 ... Coil assembly, 24m ... Resin, 26 ... Coil, 30・ ・ Beam member, 31 ・ ・ 2nd beam member, 34 ・ ・ Wiring member, 36 ・ ・ Connector, 50 ・ ・ Movable, 52 ・ ・ Field magnet, 54 ・ ・ Yoke, 60 ・ ・ Magnetic gap, 100・ ・ Linear motor.

According to the present invention, it is possible to provide a linear motor that facilitates the manufacture of armature coils.

Claims (6)

Movables including field magnets and
A stator including a plurality of coil modules connected in the movable direction of the mover, and a stator.
With
The coil module is a linear motor including a plurality of coils arranged in the movable direction. The linear motor according to claim 1, wherein the number of coils of the plurality of coils is an integral multiple of 3. The linear motor according to claim 1 or 2, wherein the number of coils of the plurality of coils is 6 or less. The linear motor according to any one of claims 1 to 3, wherein the coil module has a connector including electrodes electrically connected to the plurality of coils. The method for manufacturing a linear motor according to claim 1.
To accommodate multiple coils in the case,
To form a coil module by pouring resin into a case that houses multiple coils,
By arranging a plurality of coil modules in the movable direction and fixing them to the beam member,
Electrically connecting the wiring member to the coil and
A method for manufacturing a linear motor, which comprises. Forming a coil module is
The method for manufacturing a linear motor according to claim 5, further comprising fixing a lid to a case into which a resin is poured.

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