TWI713283B - Linear motor, method of manufacturing linear motor - Google Patents

Abstract

The present invention is made in view of the problem that it is difficult to manufacture the armature coil by a common mold or resin molding equipment when the armature coil is particularly long, and its purpose is to provide a linear motor that can easily manufacture the armature coil. The linear motor (100) includes a movable element (50) including a field magnet (52); and a fixed element (10) including a plurality of coil modules (20) connected along the movable direction of the movable element (50). The coil module (20) includes a plurality of coils (26) arranged along the movable direction.

Description

Linear motor, method of manufacturing linear motor

The invention relates to a linear motor and a manufacturing method of the linear motor.

In order to convert electrical energy into linear motion, linear motors are used. As a kind of linear motor, there is a moving magnet type linear motor in which a magnet moves along a coil. For example, Patent Document 1 describes a moving magnet type linear slider in which an armature coil is provided in a fixed member and a field magnet is provided in a movable member. (Prior technical literature) (Patent Document) Patent Document 1: International Publication No. 2005/122369

(Problems to be solved by the present invention) The inventors have obtained the following knowledge about a moving magnet type linear motor (hereinafter referred to as a linear motor). In many cases, linear motors have different movable strokes of their movable parts depending on their applications. Therefore, the linear motor needs to prepare armature coils of different lengths according to the desired movable stroke. That is, in order to cope with various applications, it is necessary to manufacture armature coils of different lengths according to the application. Sometimes a plurality of coils arranged in a movable direction are molded by resin to manufacture an armature coil. At this time, it is necessary to prepare molds of different lengths according to the purpose, so it is not economical. In addition, 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. Based on these circumstances, the inventors of the present invention have confirmed that there is still room for improvement in linear motors from the viewpoint of ease of manufacturing the armature coil. This problem is not limited to armature coils manufactured by resin molding, and may also occur in armature coils manufactured by other methods. The present invention was completed in view of such problems, and its purpose is to provide a linear motor that can easily manufacture an armature coil. (Means to solve the problem) In order to solve the above-mentioned problems, a linear motor of one aspect of the present invention includes: a movable element including a field magnet; and a fixed element including a plurality of coil modules connected along the movable direction of the movable element. The coil module includes a plurality of coils arranged along the movable direction. Another aspect of the present invention is a method of manufacturing a linear motor. The method is a method of manufacturing the above-mentioned linear motor, which includes: a step of accommodating a plurality of coils in a housing 22; a step of pouring a resin on the housing accommodating the plurality of coils to form a coil module; and arranging the plurality of coils in a movable direction The step of fixing two coil modules to the beam member; and the step of electrically connecting the wiring member 34 to the coil 26. (Effect of Invention) According to the present invention, it is possible to provide a linear motor that can easily manufacture an armature coil.

Hereinafter, the present invention will be described with reference to the drawings based on preferred embodiments. In the embodiment and modification examples, the same or equivalent constituent elements and members are denoted by the same reference numerals, and repeated descriptions are appropriately omitted. In addition, in order to facilitate understanding, the dimensions of the members in each drawing are appropriately enlarged and reduced. In addition, in each drawing, a part of components that are not important in the description of the embodiment are omitted and shown. In addition, in the following description, "parallel" and "perpendicular" not only include complete parallel and perpendicular, but also include deviations from parallel and perpendicular within the error range. In addition, "approximately" means the same in the approximate range. In addition, terms including ordinal numbers such as first and second are used to describe various constituent elements, but the terms are used only for the purpose of distinguishing one constituent element from other constituent elements, and the constituent elements are not limited by the terms. In addition, the linear motor includes those whose movable element moves on a curved track such as an arc, and is not limited to those whose movable element moves on a linear track. [Implementation form] Referring to the drawings, the linear motor 100 according to the embodiment of the present invention will be described. Fig. 1 is a plan view showing a linear motor 100 of the embodiment. FIG. 2 is a side sectional view taken along the line A-A of the linear motor 100. Hereinafter, the description is mainly based on the XYZ orthogonal coordinate system. The X-axis direction corresponds to the left-right direction on the paper surface in Fig. 1 and corresponds to the direction perpendicular to the paper surface in Fig. 2. The Y-axis direction corresponds to the vertical direction on the paper 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 on the paper surface in FIG. 2. The Y-axis direction and the Z-axis direction are orthogonal to the X-axis direction, respectively. The positive direction of each of the X-axis, Y-axis, and Z-axis is defined as the direction of the arrow in each figure, and the negative direction is defined as the direction opposite to the arrow. In addition, the positive direction side of the X-axis may be referred to as the "right side", and the negative direction side of the X-axis may be referred to as the "left side". In addition, the positive direction side of the Y axis is sometimes referred to as the "front side", the negative direction side of the Y axis is referred to as the "rear side", the positive direction side of the Z axis is referred to as the "upper side", and the negative direction of the Z axis The side is called the "lower side". This kind of direction mark does not limit the use posture of the linear motor 100, and the linear motor 100 can be used in any posture according to the application. (Linear motor) The linear motor 100 includes a fixed element 10 and a movable element 50. The movable element 50 forms a magnetic circuit in the magnetic gap 60. The linear motor 100 functions as an energy conversion mechanism that causes the stator 10 to generate thrust in the movable direction in the magnetic gap 60. In the embodiment, the movable direction is arranged to coincide with the X-axis direction. (Movable part) First, the movable element will be explained. The movable element 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 constitute a magnetic circuit that forms a field magnetic field in the magnetic gap 60. The magnetic gap 60 is a gap between a pair of field magnets 52. The pair of yokes 54 are plate-shaped members that extend in the X-axis direction and the Y-axis direction and are thin in the Z-axis direction. When viewed in a plan view, the pair of yokes 54 has a substantially rectangular profile, and the profile has two sides parallel to the X-axis direction and two sides parallel to the Y-axis direction. The pair of yokes 54 are formed of various known soft magnetic materials. The pair of yokes 54 are spaced apart in the Z-axis direction and arranged parallel to each other. The spacer 56 is arranged in the upper region between the pair of yokes 54 and maintains the interval of 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, bolts) through a plurality of through holes provided near the upper ends thereof. The field magnet 52 functions as a supply source of magnetic flux that forms a field magnetic field in the magnetic gap 60. The field magnet 52 may also include one or more magnets. The field magnet 52 may also be configured by arranging a plurality of magnets into a Halbach array. On the surface of the field magnet 52, a plurality of magnetic poles are provided at predetermined intervals along the X-axis direction. In the embodiment, 6-pole magnetic poles are provided. The field magnet 52 may also be formed of various known magnet materials. In this example, the field magnet 52 is formed of a rare earth magnet material such as NdFeB. The field magnet 52 may be fixed to the yoke 54 by a known method such as bonding. (Fastener) The fixing member 10 includes a plurality of coil modules 20, a beam member 30, a second beam member 31, and a wiring member 34 extending in the X-axis direction. The plurality of coil modules 20 are arranged along the movable direction, that is, the X-axis direction. In a plan view, the coil module 20 has a substantially rectangular shape, for example, and is a substantially plate-shaped member thinner in the Z-axis direction. In this example, in a plan view, the coil module 20 is arranged with a long side along the X-axis direction and a short side along the Y-axis direction. The coil module 20 includes a coil assembly 24 and a housing 22. The coil assembly 24 includes a plurality of coils 26 and connectors 36 arranged along the X-axis direction. The plurality of coils 26 are integrated by being wrapped with resin 24m. When the case 22 is installed, as an example, the coil assembly 24 is formed by pouring resin 24m on the case 22 in which a plurality of coils 26 are arranged. In addition, the housing 22 is not necessarily provided. When the housing 22 is not provided, as an example, the coil assembly 24 is formed by insert molding in which resin 24m is poured into a mold in which a plurality of coils 26 are arranged. These manufacturing methods are always only examples, and the coil assembly 24 can also be formed by other various manufacturing methods. The coil 26 has a substantially rectangular outline with two sides parallel to the X-axis direction and two sides parallel to the Y-axis direction, and four corners are formed in an R shape. The coil 26 may have a contour formed by a curve such as an ellipse as a whole without 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 metal wire wound around the Z axis. When a drive current is supplied to the coil 26, the coil 26 functions as an armature coil that generates magnetic flux in the Z-axis direction and generates thrust 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 can be connected to the lead wires of the plurality of coils 26 before insert molding, and integrated with the plurality of coils 26 by insert molding. Alternatively, the connector 36 may be connected to the leads of a plurality of coils 26 after insert molding. In this case, the lead wire may be directly drawn from the coil 26, and the connector 36 may be connected to the tip of the lead wire. The housing 22 is provided to cover the circumference of the coil group 24. The case 22 suppresses the outflow of gas generated from the resin 24m surrounding the coil 26 or the periphery of the coil 26 to the outside. The casing 22 is a cubic box body composed of a box-shaped casing main body 22b and a cover 22c covering the upper surface of the casing main body 22b, and the casing main body 22b is composed of five surfaces with an open upper surface. The cover 22c may be fixed to the upper surface of the housing body 22b containing the coil assembly 24 by welding or the like, for example. The housing 22 may also be formed of metallic materials such as non-magnetic stainless steel or non-metallic materials such as ceramics. Next, the wiring member 34 will be described. FIG. 3 is a plan view schematically showing the fixture 10. FIG. 4 is an explanatory diagram for explaining the wiring of the fixture 10. The wiring member 34 functions as a path for supplying current from the drive circuit 40 to the coil 26. The current from the drive circuit 40 flows to the coil 26 via the wiring member 34, the connector 36, and the lead wire 26 b connected to the electrode of the connector 36. The wiring member 34 is, for example, a metal 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 connection with the connector 36 is mounted. In the embodiment, the wiring member 34 is accommodated in the passage recess 30b of the beam member 30 described later. As a method of supplying drive currents to the plurality of coil modules 20, a full excitation method and a partial excitation method can be considered. The full excitation method is a method for supplying drive current to all the coils constituting one phase. The full excitation method has the feature of easier wiring. The partial excitation method is a method of selectively supplying drive current to the coil 26 near the movable element 50. The partial excitation method has the characteristic of low power waste. In the embodiment, a partial excitation method is adopted. As shown in FIG. 4, each coil module 20 and other modules are independently connected to the drive circuit 40. The beam member 30 and the second beam member 31 function as beams for connecting a plurality of coil modules 20 and giving desired rigidity to the fixture 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 recessed portion 30b is a recessed portion opened on the side of the coil module 20 and receded upward. The passage recess 30 b accommodates the connector 36 and the wiring member 34. The beam member 30 is arranged to be in contact with the upper surface of the coil module 20, and the second beam member 31 is arranged 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 performing 3-phase driving, the number of coils is preferably an integer multiple of 3. In addition, the number of coils is not necessarily an integral multiple of 3, and the number of coils can be set arbitrarily. In other words, the coil module 20 may be composed of a number of coils 26 other than an integral multiple of 3 as required. In particular, when performing partial excitation by a moving magnet type, it is sufficient to excite the coil 26 that is an integer multiple of 3, so that it can be modularized other than an integer multiple of 3. In the case of a motor with a long movable stroke, if the number of coils is three, the number of coil modules increases and the manufacturing cost becomes higher. Therefore, the number of coils is preferably six. In the case of a motor with a short movable stroke, if the number of coils is 6 or more, the fixing member may become unnecessarily long. Therefore, the number of coils is preferably 3. If one coil module 20 becomes too long, the possibility of the coil module 20 being warped and contacting the movable element 50 increases. From this viewpoint, 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 step diagram illustrating the manufacturing step S80 of the linear motor 100. In particular, the manufacturing step S80 includes steps S82 to S92 of manufacturing the fixing member 10. In step S82, the surface of the winding is insulated with a metal wire to produce a hollow coil 26. In step S84, the plurality of coils 26 are housed in the housing main body 22b. Before or after being accommodated in the housing body 22b, the connector 36 is installed on the plurality of coils 26. In the embodiment, the connector 36 is attached to the coil 26 before being accommodated in the housing body 22b. The connector 36 is integrated with the coil 26 by the resin 24m poured in the next step. In step S86, by pouring the resin 24m on the housing body 22b containing the plurality of coils 26, the plurality of coils 26 are integrated, thereby forming the coil group 24. In step S88, the cover 22c is covered on the housing body 22b containing the coil 26 in which the resin 24m has been poured. In step S90, the cover 22c is fixed to the housing body 22b by welding, for example. The cover 22c is provided with an opening 22e, and the connector 36 is exposed from the opening 22e when the cover 22c is fixed. In step S92, a plurality of coil modules 20 are arranged along the X-axis direction, the connector 36 is electrically connected to the wiring part of the wiring member 34, and the beam member 30 and the second beam member 31 are fixed. In this way, the fixing member 10 is manufactured. The linear motor 100 is manufactured by inserting the fixed member 10 manufactured in this way into the magnetic gap 60 of the movable member 50 manufactured separately. This manufacturing step S80 is only an example, and other steps may be added, part of the steps may be changed or deleted, or the order of the steps may be replaced. As shown in FIG. 1, between the coil module 20 and the adjacent coil module 20, the wall surface of the two-layer housing 22 is interposed. Compared with the case without such a wall surface, the outflow of gas from the resin 24m can be reduced. The operation of the linear motor 100 configured in this manner will be described. When an alternating 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 in the movable direction to the field magnet 52 of the movable element 50. The linear motor 100 drives the driving object connected to the movable element 50 by the thrust. The outline of one aspect of the present invention is as follows. The linear motor 100 of one aspect of the present invention includes: a movable element 50 including a field magnet 52; and a fixed element 10 including a plurality of coil modules 20 connected along the movable direction of the movable element 50. The coil module 20 includes a plurality of coils 26 arranged along the 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 connected coil modules 20. Therefore, the standardization of the design can be realized and the design workload can be reduced. When manufacturing by changing the movable stroke of the linear motor 100, it can be dealt with by changing the number of the coil modules 20 connected, so that molds, jigs, manufacturing equipment, etc. can be shared. Since the coil module 20 can be set to a length suitable for manufacturing, when manufacturing the long linear motor 100, the handling of the jig or the coil module 20 becomes easy. In addition, the operation 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 integer multiple of 3. In this case, compared with the case where the number of coils is other than an integral multiple of 3, it is possible to reduce the possibility that the fastener becomes unnecessarily long due to unnecessary coils. The number of coils of the plurality of coils 26 may be 6 or less. In this case, the coil module 20 can be shortened compared to when the number of coils is 7 or more. Therefore, the possibility of the coil module 20 being warped and contacting the movable element 50 can be reduced. The coil module 20 has a connector 36 including electrodes electrically connected to a plurality of coils 26. At this time, when the coil module 20 is connected, the connector 36 can be easily connected to the wiring portion of the wiring member 34. In addition, if the connector is removable, the existing linear motor can be easily disassembled and reused. When changing the stroke of an existing linear motor, the additional coil module 20 can be easily connected. Compared with the case of discarding the existing linear motor and installing a new linear motor, the waste of resources can be greatly reduced. Another aspect of the present invention is a method of manufacturing a linear motor. The method includes the steps of accommodating a plurality of coils 26 in the housing 22; pouring resin 24m on the housing 22 accommodating the plurality of coils 26 to form the coil module 20; and arranging the coil modules in the movable direction The step of fixing 20 to the beam member 30; and the step of 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 connected coil modules 20. Therefore, the standardization of the design can be realized and the design workload can be reduced. When manufacturing by changing the movable stroke of the linear motor 100, it can be dealt with by changing the number of the coil modules 20 connected, so that molds, jigs, manufacturing equipment, etc. can be shared. The step of forming the coil module 20 may include the step of fixing the cover 22c to the casing body 22b in which the resin 24m has been poured. At this time, since the cover 22c is fixed to the case body 22b, it is possible to suppress the escape of gas from the resin 24m. Above, the examples of the embodiments of the present invention have been described in detail. The foregoing embodiments are merely illustrative of specific examples when implementing the present invention. The content of the embodiment does not limit the technical scope of the present invention, and various design changes such as changes, additions, and deletions of constituent elements can be made without departing from the scope of the invention defined in the scope of the patent application. In the foregoing embodiment, the content that can be changed by this type of design is described with the marks "in the implementation form", "in the implementation form", etc., but it does not mean that design changes to the content without this kind of mark are not allowed . In addition, the hatching indicated in the cross section of the drawing does not limit the material of the object indicated by the hatching. Hereinafter, a modification example will be described. In the drawings and descriptions of the modified examples, constituent elements and members that are the same or equivalent to those of the embodiment are given the same reference numerals. The description overlapping with the embodiment is appropriately omitted, and the structure that is different from the embodiment is emphasized. (First modification) FIG. 6 is a cross-sectional view of the linear motor 200a of the first modification, and corresponds to FIG. 2. The linear motor 200a differs from the linear motor 100 in that it does not include the second beam member 31 and the other structures are the same. The second beam member 31 is not necessarily provided. (Second modification) In the linear motor 100, although the example in which the beam member 30 and the 2nd beam member 31 are not connected was demonstrated, it is not limited to this. FIG. 7 is a cross-sectional view showing the linear motor 200b of the second modification, and corresponds to FIG. 2. The linear motor 200b differs from the linear motor 100 in that instead of the beam member 30 and the second beam member 31, the linear motor 200b includes a beam member 30B, a second beam member 31B, and a spacer 35, and the other structures are the same. The beam member 30B and the second beam member 31B protrude from the coil module 20 in the negative direction on the Y axis, and a spacer 35 is provided between these protruding parts. The beam member 30B and the second beam member 31B sandwich the spacer 35 and are integrated. In the linear motor 200b, the beam member 30B and the second beam member 31B have an entry portion 30e that enters the magnetic gap 60. The entry portion 30e may be, for example, a plate-shaped portion that extends in the X-axis direction and the Y-axis direction and is thin in the Z-axis direction. The entrance portion 30e is provided to cover all or part of the coil module 20. By having the entry portion 30e, the warpage of the coil module 20 can be suppressed. The entry portion 30e can also be applied to the embodiment and other modified examples. (3rd modification) FIG. 8 is a cross-sectional view showing a linear motor 200c of a third modification example, and corresponds to FIG. 2. The linear motor 200c differs from the linear motor 200b in that it replaces the beam member 30B, the second beam member 31B, and the spacer 35, and includes the beam member 30C, and the other structures 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. (4th modification) In the embodiment, an example in which the step of manufacturing the coil module 20 and the step of connecting the coil module 20 are continuously installed has been described, but the present invention is not limited to this. In addition, it is not necessary to provide the beam member described above. For example, in the step of manufacturing the coil module 20, the coil module 20 without the beam member may be manufactured. The thus manufactured coil module 20 without beam members can be stored according to specifications such as size. At this time, the step of connecting the coil module 20 can be set in other factories. The coil module 20 of the desired specification among the stored coil modules can be transported to another factory, and the coil module 20 can be connected in the factory. (Other modifications) The linear motor 100 can also be constructed by combining coil modules 20 with different numbers of coils. The linear motor 100 may also include a linear coil module 20 and a curved coil module. A pair of yoke 54 and spacer 56 can also be seamlessly formed as one body. One of the pair of field magnets 52 that hold the coil module 20 may not be provided. Each of the above-mentioned modification examples exerts the same functions and effects as the embodiment.

10‧‧‧Fixture 18‧‧‧Coil 20‧‧‧Coil Module 22‧‧‧Shell 22b‧‧‧Shell body 22c‧‧‧cover 24‧‧‧Coil Set 24m‧‧‧resin 26‧‧‧Coil 30‧‧‧Beam member 31‧‧‧Second beam member 34‧‧‧Wiring member 36‧‧‧Connector 50‧‧‧movable parts 52‧‧‧Field Magnet 54‧‧‧Yoke 60‧‧‧Magnetic gap 100‧‧‧Linear Motor

Fig. 1 is a plan view showing a linear motor according to an embodiment of the present invention. Fig. 2 is a sectional view taken along the line A-A in Fig. 1. Fig. 3 is a plan view schematically showing the fixing member of the linear motor of Fig. 1. Fig. 4 is an explanatory diagram schematically illustrating the wiring of the fixture of Fig. 1. Fig. 5 is a step diagram illustrating the manufacturing steps of the fixing member of the linear motor of Fig. 1. Fig. 6 is a cross-sectional view of the linear motor of the first modification. Fig. 7 is a cross-sectional view of a linear motor according to a second modification. Fig. 8 is a cross-sectional view of a linear motor according to a third modification.

10‧‧‧Fixture

20‧‧‧Coil Module

22‧‧‧Shell

22b‧‧‧Shell body

22c‧‧‧cover

24‧‧‧Coil Set

24m‧‧‧resin

26‧‧‧Coil

30‧‧‧Beam member

32‧‧‧Fixed member

50‧‧‧movable parts

52‧‧‧Field Magnet

56‧‧‧Spacer

58‧‧‧Fixture

100‧‧‧Linear Motor

Claims (5)

A method for manufacturing a linear motor, comprising: a movable element including a field magnet; and a fixed element including a plurality of coil modules connected along the movable direction of the movable element, the coil modules including the coil modules arranged along the movable direction The coil module has a connector, and the connector includes electrodes electrically connected to the leads of the plurality of coils. The method of manufacturing the linear motor includes: pouring resin on the Insert molding in the mold of the coil forms the coil module; before the insert molding, the connector is connected with the leads of the plurality of coils, and is integrated with the plurality of coils by the insert molding. According to the method of manufacturing a linear motor described in the first item of the scope of patent application, the number of coils of the plurality of coils is an integer multiple of 3. According to the method of manufacturing a linear motor described in item 1 or 2 of the scope of patent application, the number of coils of the plurality of coils is 6 or less. A method of manufacturing a linear motor includes: a step of accommodating a plurality of coils in a housing; a step of pouring a resin into the housing accommodating the plurality of coils to form a coil module; and arranging the plurality of coil modules along the aforementioned movable direction And the step of fixing to the beam member; and the step of electrically connecting the wiring member to the coil. According to the method of manufacturing a linear motor described in claim 4, the step of forming the coil module includes the step of fixing the cover to the resin-filled housing.

Images