JP2009247191A - Cylindrical coil and cylindrical micromotor and method of manufacturing of cylindrical coil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a minimum-diameter cylindrical coil having a highly accurate and minute conductive pattern made of aluminum base with its cross section of a high aspect ratio in order to economically achieve a cylindrical micromotor excellent in torque characteristic of outer diameter of ≤ϕ1 mm. <P>SOLUTION: While a resist material is patterned in a desired coil form on the outer perimeter of a cylindrical hollow base made of aluminum as a conductive material, anodization is performed by controlling current distribution with the cylindrical hollow aluminum base as an anode. Then, a cylindrical coil 10 with a coil pattern made up of an insulating portion 10i made of aluminum oxide and a conductive portion 10c made of aluminum is formed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an extremely small diameter cylindrical coil having a fine coil pattern, a method of manufacturing the cylindrical coil, and a cylindrical micromotor having the cylindrical coil.

  In recent years, micro-motors with an extremely small diameter of about φ2 mm have been developed. However, various devices used in the fields of medical equipment, analytical equipment, etc. are equipped with actuators in extremely narrow spaces for the purpose of achieving high functionality. Further miniaturization of the micromotor is desired.

  As the micromotor is reduced in size and diameter, it is essential to reduce the size and size of the coil built in the micromotor.

  Generally, a coil used for a cylindrical micromotor is formed by winding a self-bonding copper wire having a fusion layer on the outermost layer of an insulation-coated copper wire into a hollow cylindrical shape or a cup shape. FIG. 9 is a perspective view of a coil in which a self-bonding copper wire is formed into a hollow cylindrical shape by this method.

  Micro motors can also be made compact by rolling flat so-called sheet coils formed by etching metal foil such as copper foil or printing coil patterns with a conductive paste. It is used to cope with.

  When the cylindrical coil formed by these methods is used as a stator coil of a DC brushless motor equipped with a rotor magnet, particularly in a cylindrical micromotor, the cylindrical coil is inserted into the housing of the motor, Secure to the wall.

  For example, in Patent Document 1, a sheet coil having a structure in which a copper foil coil portion is printed on a flexible substrate and a cover film is coated thereon is wound into a cylindrical shape and used as a stator coil of a brushless motor. Embodiments are described.

  On the other hand, for a planar coil applicable to a flat motor, a thin film coil for a small motor in which a coil pattern is formed on a foil or film made of aluminum with a conductive part and a non-conductive part made of an alumite layer, It is disclosed in Patent Document 2.

No. 7-41129 Japanese Patent Laid-Open No. 5-292692

  However, when the outer diameter of the cylindrical micromotor reaches φ1.5 mm or less, especially φ1.0 mm or less, the cylindrical coil molding method according to the prior art is used as a stator coil of the micromotor for the following reasons. It becomes technically difficult to use.

  First, in the case of a cylindrical coil formed of a self-bonding copper wire, generally, the shape tends to be lost when the coil is formed, and mechanical accuracy such as roundness and flare is lowered.

  At this time, when the coil has low mechanical accuracy such as roundness and flare, when used as a stator coil of a cylindrical micromotor, the stator coil and the rotor magnet disposed inside the stator coil may interfere with each other. Therefore, a large air gap, which is the gap between the rotor magnet and the stator coil, must be secured.

  As a result, since a large magnetic gap from the inner diameter of the housing of the cylindrical micromotor to the outer diameter of the rotor magnet must be ensured, the torque generation efficiency is reduced and is not suitable for a reduction in diameter.

  In addition, the wiring work from the stator coil to the power feeding part in the housing of the micro motor having an outer diameter φ of 1.5 mm or less is very difficult because it is a work in a very narrow space.

  Next, in the case of a cylindrical coil using a sheet coil, as in the case of a cylindrical coil formed of a self-bonding copper wire, the roundness should be accurately formed and fixed to the inner wall surface of the motor housing. Is extremely difficult.

  Originally, a sheet coil made of a highly flexible base material can be arranged in accordance with the inner peripheral surface of the cylinder. However, when the inner peripheral surface of the cylinder has an outer diameter of φ1.5 mm or less, its curvature is too large. This is because the limit of the allowable range for bending the base material of the sheet coil is exceeded.

  Further, in a cylindrical coil for a cylindrical micromotor, it is effective to increase the conductor cross-sectional area as a means for improving torque. On the other hand, increasing the number of turns is effective for improving the torque constant.

  However, according to the etching for forming the coil pattern of the sheet coil and the printing technique of the conductor pattern, it is possible to form the coil pattern at intervals of several μm, but the aspect of the thickness and width of the conductor pattern The ratio must be low.

  The reason is that in the etching method, when unnecessary portions of the material are removed by the corrosive agent, the corrosion progresses isotropically. Therefore, when the aspect ratio is to be increased, the etching is performed in the thickness direction of the material. This is because the etching is performed in a direction perpendicular to the thickness direction of the material below the resist film.

Moreover, in the method by the printing technique of the conductor pattern, in general, conductive particles of nanometer size are printed and sintered on the surface of the base material on which the pattern is formed.
In order to obtain a high aspect ratio, there is a limit to increasing the thickness of the conductor portion.

  Therefore, in order to obtain the necessary conductor cross-sectional area, the width of the conductor pattern must be increased, and in order to secure the necessary number of turns, it is necessary to increase the number of layers, and more Vertical wiring is required.

  As a result, in order to obtain sufficient torque characteristics as a motor, a complicated process is required in manufacturing.

  Similarly, since the thin-film coil formed on the foil or film made of aluminum disclosed in Patent Document 2 is also thin, naturally the aspect ratio between the thickness and the width of the conductor portion should be increased. In order to improve the torque characteristics of the motor, it is necessary to stack a large number of the thin-film coils, which has a similar problem.

  In order to solve these problems, in the cylindrical coil according to the first aspect of the present invention, an insulator portion made of aluminum oxide formed by anodizing a part of a hollow cylindrical aluminum base, and an aluminum base A coil pattern is formed by a conductor portion made of aluminum which is a portion of the material that has not been anodized.

  According to a second aspect of the present invention, in the cylindrical coil of the first aspect, the radial thickness of the insulator portion and the cylindrical shape in the minimum width portion of the insulator portion in the coil pattern. The aspect ratio (= thickness in the radial direction / width) with respect to the minimum width of the insulator portion at the outer periphery of the coil is 2 or more.

  According to a third aspect of the present invention, the cylindrical coil according to the first or second aspect has a plurality of conductor portions.

  Furthermore, at least a part of the outer peripheral side surface of the cylindrical coil is covered with an insulating layer made of an insulator, and the plurality of conductor portions are filled with through holes formed in the insulating layer by drilling. The structure is electrically connected by a conductor layer formed on at least a part of the insulating layer via the.

  A cylindrical micromotor according to a fourth aspect of the present invention has a structure having the cylindrical coil according to any one of the first to third aspects.

  A cylindrical micromotor according to a fifth aspect of the present invention is the cylindrical micromotor according to the fourth aspect, wherein a part of the cylindrical coil is exposed as a power feeding portion.

  In the method for manufacturing a cylindrical coil according to the invention described in claim 6, a resist is arranged on a cylindrical base material made of aluminum, and a resist patterning step for determining a pattern shape of the coil pattern, and anodization, An insulating process for insulating a part of the cylindrical base material is performed.

  Furthermore, the cylindrical coil of Claim 1 or 2 is formed by performing the resist removal process which removes a resist, and the internal diameter Al removal process which removes the aluminum which remains on the whole internal peripheral surface of a cylindrical base material. The manufacturing method is used.

  The cylindrical coil manufacturing method according to claim 7 is the cylindrical coil manufacturing method according to claim 6, wherein the resist patterning step includes a hydrophobic self-assembled monolayer and a hydrophilic self-organization. The coil pattern made of metal is transferred onto a transparent and flexible polymer substrate by using the monomolecular film.

  Furthermore, a manufacturing method is used in which a coil pattern is patterned by photolithography on a cylindrical base material made of aluminum coated with a photoresist using a polymer substrate as a photomask.

  According to the first aspect of the present invention, since the coil pattern is previously formed on the aluminum base having a hollow cylindrical shape, the obstruction due to the sheet rigidity as in the case where the sheet-like coil is formed in a cylindrical shape can be eliminated. A cylindrical coil that can be applied as a stator coil of a micromotor having high mechanical accuracy such as roundness and flare and having an outer diameter of φ1.5 mm or less can be obtained.

  According to the second aspect of the present invention, it is possible to obtain a cylindrical coil capable of increasing the number of turns and realizing a necessary torque constant without making the conductor pattern a multilayer structure.

  According to the invention of claim 3, it is possible to obtain a cylindrical coil in which a plurality of conductor portions forming a coil pattern are reliably connected while maintaining the cylindrical shape.

  According to the invention described in claim 4, since the air coil which is the gap between the rotor magnet and the stator coil can be reduced by mounting the cylindrical coil having excellent roundness of the present invention as the stator coil. A highly efficient cylindrical micromotor can be obtained.

  According to the fifth aspect of the present invention, by using a part of the lead portion of the cylindrical coil as the power feeding portion, wiring work that becomes extremely difficult is unnecessary particularly in the internal space of the extremely small diameter cylindrical micro motor housing. A cylindrical micromotor having the above structure can be obtained.

  According to the method for manufacturing a cylindrical coil according to the sixth aspect of the present invention, the current distribution is controlled, and the anodization of the aluminum cylindrical base material can be performed selectively and concentrated. A cylindrical coil composed of a conductor portion and an insulator portion can be manufactured.

  As a result, as in the case of forming a stator coil of a motor by a method using a printing technique or the like, a complicated process in manufacturing, in which the number of layers is increased to obtain sufficient torque characteristics and each layer is vertically wired. Since it is not necessary, an economical and high quality cylindrical coil can be manufactured.

  According to the method of the seventh aspect of the present invention, it is possible to dispose a resist that forms a highly precise coil pattern on a cylindrical base material of an extremely small diameter made of aluminum.

  Embodiments of a cylindrical coil and a cylindrical micromotor according to the best mode of the present invention will be described below with reference to the accompanying drawings. In addition, the same code | symbol is attached | subjected about the same component in each embodiment.

<Embodiment 1>
FIG. 1 is a perspective view schematically showing a process of forming a cylindrical coil 10 according to the first embodiment of the present invention.

  As shown in FIG. 1B, the cylindrical coil 10 is formed by patterning a resist R into a coil shape with respect to an aluminum cylindrical base material 10 ′ composed of only the conductor portion 10c shown in FIG. It can be obtained by performing anodizing treatment in the tempered state.

  FIG.1 (c) is the cylindrical coil 10 obtained by the anodizing process. The cylindrical coil 10 shown in FIG. 1 (c) has the resist R arranged in FIG. 1 (b) removed, and is formed by an insulator portion 10i made of aluminum oxide and a conductor portion 10c made of aluminum. A pattern is formed.

  Further, FIG. 1D shows a state in which neutral points of a plurality of coils formed in the cylindrical coil 10 are connected by a neutral point connection layer 10s. As a result, it can be mounted as a stator coil of a cylindrical micromotor.

  The above is the outline of the process for forming the cylindrical coil 10 according to the first embodiment of the present invention. Details of the process will be described below.

  The cylindrical coil 10 is formed on an aluminum cylindrical substrate: [1] resist patterning step, [2] insulation treatment (anodization) step, [3] resist removal step, [4] inner diameter Al removal step, [5] Manufactured by performing a main process including a neutral point connection process.

  FIG. 2 shows a process of forming aluminum oxide as an insulator on a predetermined portion of an aluminum cylindrical base material 10 ′ as a conductor by these steps. 3 is a developed cylindrical view showing a cross-sectional state of the coil 10. FIG.

  FIG. 2A shows the [1] resist patterning step, and shows a state in which the resist material R is arranged on the outer peripheral surface of the aluminum cylindrical base material 10 ′ where aluminum oxide as an insulator is not formed. ing.

  At this time, as a resist patterning method, various methods can be applied in addition to a microcontact printing method for transferring SAM with a PDMS (polydimethylsiloxane) stamp coated with SAM (self-assembled monolayer). However, the optical soft lithography method is suitable for forming a precise pattern on a cylindrical aluminum substrate.

  Here, the optical soft lithography method uses a different SAM having hydrophobic and hydrophilic characteristics to transfer a metal micropattern onto a transparent and flexible polymer substrate, and the polymer substrate is a photomask. As a method, a three-dimensional substrate coated with a photoresist is patterned by photolithography.

  FIG. 3 shows a process of resist patterning on the cylindrical side surface of the aluminum cylindrical base material 10 'by an optical soft lithography method. The resist material is patterned as follows.

  A hydrophobic self-assembled monolayer So is applied to the surface of the silicon substrate 2. [See Fig. 3 (a)]

  A metal micropattern 3 is arranged on the self-assembled monolayer So. [Refer to FIG. 3 (b)]

  A hydrophilic self-assembled monolayer Sm is applied to the surface of the metal micropattern 3. [Refer to FIG. 3 (c)]

  The metal micropattern 3 is transferred to a transparent and flexible polymer substrate 4 made of PDMS (polydimethylsiloxane). [Refer to FIG. 3 (d)]

  A positive photoresist Rp is coated on the outer peripheral cylindrical side surface of the aluminum cylindrical substrate 10 '. [See Fig. 3 (e)]

  The polymer substrate 4 onto which the metal micropattern 3 has been transferred in advance using a self-assembled monolayer is brought into close contact with at least a part of the outer cylindrical surface of the aluminum cylindrical substrate 10 ′ coated with the photoresist Rp. [Refer to FIG. 3 (f), (g)]

  The positive type photoresist material Rp other than the metal micropattern 3 is exposed by irradiating with UV light. [See Fig. 3 (g)]

  The polymer substrate 4 is removed from the aluminum cylindrical base material 10 ′, and the aluminum cylindrical base material 10 ′ is immersed in a developer to dissolve the exposed portion of the photoresist Rp.

  The portion of the photoresist Rp that has not been exposed remains patterned as a resist R on the cylindrical side surface of the outer peripheral portion of the aluminum cylindrical substrate 10 '. [See Fig. 3 (h)]

  FIGS. 2B-1 and 2B-2 show the [2] insulating treatment (anodization) step. Here, the anodic oxidation of aluminum is a method of forming an electrically insulating oxide on an aluminum base material by flowing an electric current in an electrolytic solution such as oxalic acid using the aluminum base material as an anode.

In FIG. 2B-1, the aluminum base material 10 ′ is anodized by flowing an electric current in the electrolytic solution with the cylindrical aluminum base material 10 ′ as the anode and the counter electrode m as the cathode. Then, an electrically insulating aluminum oxide (Al ₂ O ₃ ) is formed.

  An arrow extending from the aluminum substrate 10 ′ to the counter electrode m represents a vector indicating the current flow at this time.

  As this vector shows, the current flowing through the outer peripheral portion from the inner peripheral portion of the aluminum base material 10 ′ and flowing to the counter electrode m is not patterned on the resist which is an insulator in the outer peripheral portion of the aluminum base material 10 ′. Concentrate on the part.

  Further, regarding the actual arrangement of the aluminum base material 10 ′ and the counter electrode m, the aluminum base material 10 ′ is arranged inside the counter electrode m having a larger inner diameter than the outer diameter of the cylindrical aluminum base material 10 ′. It is in a state.

  With this arrangement, only the outer peripheral portion of the cylindrical aluminum base material 10 ′ is opposed to the electrode m, and a current flows between the portion that is not registered on the outer peripheral portion of the aluminum base material 10 ′ and the electrolytic solution. Then, a solid-liquid interface reaction occurs, and porous aluminum oxide is formed with an insulator.

  FIG. 2 (b) -2 shows that the insulator part 10i made of aluminum oxide is formed by anodization from the part where the resist on the outer peripheral surface of the aluminum base 10 ′ is not patterned, and the inner periphery of the aluminum base 10 ′. It represents a state where it is widened toward the part.

  Since the current flowing during anodization is concentrated from the inner periphery of the aluminum base 10 ′ to the portion where the resist on the outer periphery is not patterned, anodization is performed from the portion without the resist toward the inner periphery, Progressing toward the end, an insulator portion 10i made of aluminum oxide is formed.

  FIG. 2C shows a [3] resist removal step, and shows a state in which the resist R is dissolved and removed by a stripping solution.

  As the stripper used for removing the resist R, an appropriate one is used according to the type of the resist material. When the resist R is a positive photoresist Rp, an organic amine represented by ethanolamines and the like are used. Use a mixture of polar solvents.

  FIG. 2D shows a [4] inner diameter Al removal step, where the aluminum remaining on the entire inner peripheral surface of the cylindrical aluminum base material 10 ′ is removed, and the coil pattern of the conductor portion 10c is made of aluminum. The formed state is shown.

  The cylindrical shape shown in FIG. 1 (c), in which at least a part of the electric path made of the conductor portion 10c made of aluminum is formed in a substantially spiral shape by this step, and at least a plurality of the coil portions are formed. Coil 10 is obtained.

  FIG. 2E shows a [5] neutral point connection step, in which a neutral point connection layer 10 s composed of an insulator layer 10 si and a conductor layer 10 sc is disposed on the outer peripheral surface of the cylindrical coil 10. Represents.

  Here, the neutral point N of the cylindrical coil 10 is the center of the spiral in the electrical path that forms a substantially spiral coil portion or the electrical path that forms a lead portion that is a portion other than the substantially spiral coil portion and the coil portion. It refers to the vicinity of the end on the direction side. (See Figure 4)

  In this step, the neutral point connection layer 10s is formed by the following procedure, thereby connecting the neutral points of the plurality of coil portions formed on the cylindrical coil 10.

  First, in the cylindrical coil 10, an insulating layer 10 si is formed by coating an insulating synthetic resin on the outer peripheral surface excluding a portion near the open side of the lead portion.

  Next, by drilling using a laser or the like, a through hole is formed by drilling the neutral point N of the cylindrical coil 10 having the insulator layer 10si formed in the radial direction until the neutral point N is reached. To do.

  Next, electroless plating such as copper is performed on at least a part of the part where the insulator layer 10si is formed and a part where the through hole is formed, thereby forming the conductor layer 10sc. By this conductor layer 10sc, each neutral point is connected through a through hole.

  Furthermore, the neutral point connection layer 10s is formed by coating the synthetic resin of the insulator on the conductor layer 10sc to form the insulator layer 10si.

  As described above, the cylindrical coil 10 having the coil pattern of the insulator portion 10i made of aluminum oxide and the conductor portion 10c made of aluminum by the process of [1] resist patterning step to [5] neutral point connecting step. Obtainable.

  The cylindrical coil 10 includes a plurality of coil portions to which neutral points are connected, and a part of the outer peripheral portion is coated with an insulator, so that it is fixed as a stator coil on the inner peripheral portion of the cylindrical micromotor housing. In this case, insulation can be ensured.

  In addition, the problem that it is difficult to form a stator coil of a motor with a very small diameter, which has been formed by a self-bonding copper wire or a sheet coil according to the prior art, with high mechanical accuracy, It is possible to form a cylindrical coil having a very small diameter used for a cylindrical micromotor having an outer diameter of φ1.5 mm or less with high mechanical accuracy.

<Embodiment 2>
FIG. 5 illustrates an anodizing method in an insulating treatment (anodizing) step of an aluminum cylindrical base material 10 ′, which is one of the processes for forming a cylindrical coil according to the second embodiment of the present invention. is there.

  In the second embodiment of the present invention, the electrode p arranged on the insulator base 5 is used as the counter electrode of the electrode m, so as to correspond to the portion where the resist R on the outer peripheral surface of the aluminum cylindrical base material 10 ′ is not patterned. It arrange | positions at the inner peripheral side of aluminum cylindrical base material 10 '.

  With the configuration shown in FIG. 5, the aluminum cylindrical base material 10 ′ is anodized in the electrolyte, thereby controlling the current distribution as indicated by the arrows in FIG. It can be carried out.

  With this configuration, an insulator portion having an aspect ratio of 2 or more can be formed in the aluminum cylindrical base material 10 ′, and a conductor portion having an aspect ratio proportional to the aspect ratio of the insulator portion can be obtained.

  Here, the aspect ratio of the insulator part is the radial thickness of the insulator part and the cylindrical shape in the part where the width of the insulator part between the conductor parts is the smallest in the substantially spiral coil pattern. The ratio (thickness / width in the radial direction) to the minimum width of the insulator portion at the outer periphery of the coil is shown.

  In addition, the aspect ratio of the conductor part is determined by the radial thickness of the conductor part sandwiched between the insulator parts on both sides in the substantially spiral coil pattern, and the electric path formed by the conductor part on the outer peripheral part of the cylindrical coil. The ratio to the width (thickness / width in the radial direction) is shown.

  Since the normal anodizing process is an isotropic process, if the current distribution is not controlled, the aspect ratio of the insulator portion made of aluminum oxide formed by anodizing is about 1, but the current distribution is controlled. By selectively concentrating and anodizing, an insulator portion having an aspect ratio of 2 or more can be formed in the aluminum cylindrical base material 10 ′.

  Since the aspect ratio of the conductor part sandwiched between the insulator parts and having the same thickness as the insulator part is proportional to the aspect ratio of the insulator part, a coil pattern having a high aspect ratio cross-sectional area is formed, and the required torque It becomes possible to secure the conductor cross-sectional area and the number of turns for obtaining the characteristics.

<Embodiment 3>
FIG. 6 illustrates a method of anodization in an insulating treatment (anodization) process of an aluminum cylindrical base material 10 ′, which is one of the processes for forming a cylindrical coil according to the third embodiment of the present invention. is there.

  In the third embodiment of the present invention, the resist Rc patterned on the outer peripheral surface of the aluminum cylindrical base material 10 ′ is a conductor, and this conductor resist Rc is used as a cathode for the power source 6. On the other hand, the aluminum cylindrical base material 10 ′ is used as an anode for the power source 6.

  Furthermore, by using the cylindrical aluminum substrate 10 'as the anode and the counter electrode m as the cathode of the power source 1, when anodizing is performed in the electrolytic solution, the strong electric field generated between the conductor resist Rc and the anode causes the anode The current distribution of the oxidized portion can be guided.

  With the configuration shown in FIG. 6, the aluminum cylindrical base material 10 ′ is anodized in the electrolytic solution, so that the current distribution is generated by the strong electric field generated between the conductor resist Rc and the anode as shown by the arrow in FIG. It is possible to guide and selectively concentrate the anodic oxidation in the thickness direction of the aluminum cylindrical substrate 10 ′.

  As a result, the insulator portion made of aluminum oxide having a high aspect ratio in the aluminum cylindrical base material 10 ′ can be easily formed with a simple configuration.

  Specifically, for example, an insulator portion made of aluminum oxide having a width of 10 μm and an aspect ratio of 10 can be formed on a hollow aluminum cylindrical base material having an outer diameter of 0.7 mm and an inner diameter of 0.5 mm.

<Embodiment 4>
FIG. 7C is a perspective view of a cylindrical brushless motor 20 having an outer diameter of φ1.0 mm, in which the cylindrical coil 10 is fixed to the inner wall surface of the motor housing as a stator coil, according to the fourth embodiment of the present invention.

  The cylindrical brushless motor 20 includes a cylindrical coil 10 shown in FIG. 7 (a) in which a portion without the neutral point connection layer 10s is processed into the shape shown in FIG. 7 (b) except for the lead portion. Has been.

  FIG. 8 is a structural diagram of the cylindrical brushless motor 20, and the cylindrical coil 10 is fixed to the inner wall surface of the housing 7 as a stator coil. Further, the bearing 9 provided on the flanges 11 and 12 has a structure for supporting the rotor including the rotor magnet 8 and the output shaft 15.

  A feeding portion 10e, which is a part of the cylindrical coil 10, is exposed by the shape of the housing 7 and the flange 11 that are notched. Power supply is controlled from the power supply unit 10e, and the coil unit formed in the cylindrical coil 10 is excited to drive as a motor.

  On the other hand, FIG. 10 is a structural diagram of a general cylindrical brushless motor according to the prior art. According to this conventional structure, the power feeding unit 14 is constituted by an electric wire or an FPC board connected via the holding plate 13 fixed to the cylindrical coil 40 ′.

  According to the fourth embodiment, as compared with the conventional configuration, since a part of the lead portion of the cylindrical coil body is used as a power feeding portion without using a holding plate or the like, the number of parts can be reduced. This eliminates the need for wiring work in the internal space of the motor housing.

  Further, since the structure can be made relatively simple, it is effective in manufacturing a very small diameter motor having an outer diameter φ of 1.0 mm or less.

  The embodiments of the cylindrical coil, the manufacturing method of the cylindrical coil, and the cylindrical micromotor according to the present invention have been described above, but can be applied in various forms without departing from the scope of the present invention. .

For example, the use of a cylindrical coil is not limited to a stator coil for a brushless motor, and can be applied to any device that uses a coil.

It is a perspective view of the cylindrical coil based on Embodiment of this invention. It is a process figure of coil formation concerning an embodiment of the invention. It is the process figure which showed the patterning method of the resist based on embodiment of this invention. It is a block diagram which shows the basic composition of the cylindrical coil based on Embodiment of this invention. It is a figure which shows the anodic oxidation of the aluminum base material based on embodiment of this invention. It is a figure which shows the anodic oxidation of the aluminum base material based on embodiment of this invention. It is a perspective view of a cylindrical coil and a micro motor according to an embodiment of the present invention. 1 is a cross-sectional view of a cylindrical brushless motor according to an embodiment of the present invention. It is a perspective view of the cylindrical coil by a prior art. It is sectional drawing of the cylindrical brushless motor by a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 6 Power supply 2 Silicon substrate 3 Metal micropattern 4 Polymer substrate 5 Insulator base 7 Housing 8 Rotor magnet 9 Bearing 10 Cylindrical coil 10 'Aluminum cylindrical base material 10c Conductor portion 10i Insulator portion 10s Neutral point Connection layer 10sc Conductor layer 10si Insulator layer 10e Feed portion 11, 12 Flange 13 Holding plate 14 Feed portion 15 Output shaft 20, 30 Cylindrical brushless motor 40, 40 'Cylindrical coil N Neutral point R Resist Rp Photoresist Rc Conductive Body resist So hydrophobic self-assembled monolayer Sm hydrophilic self-assembled monolayer m, p electrode

Claims (7)

An insulator part made of aluminum oxide formed by anodizing a part of a hollow cylindrical aluminum substrate;
By the conductor portion made of aluminum which is a portion of the aluminum base that has not been anodized,
A cylindrical coil formed by forming a coil pattern. The cylindrical coil according to claim 1,
In the minimum width portion of the insulator portion in the coil pattern,
A radial thickness of the insulator portion;
A cylindrical coil having an aspect ratio (= radial thickness / width) of 2 or more with respect to a minimum width of the insulator portion at an outer peripheral portion of the cylindrical coil. In the cylindrical coil according to claim 1 or 2,
A plurality of the conductor portions;
At least a part of the outer peripheral side surface of the cylindrical coil is covered with an insulating layer made of an insulator,
The plurality of conductor portions are, by a conductor layer formed in at least a part on the insulating layer, via a conductor filled in a through hole formed by drilling in the insulating layer,
A cylindrical coil which is electrically connected.   A cylindrical micromotor comprising the cylindrical coil according to any one of claims 1 to 3 therein. The cylindrical micromotor according to claim 4, wherein
A cylindrical micromotor, wherein a part of the cylindrical coil is exposed as a power feeding unit. For cylindrical substrates made of aluminum,
A resist patterning process for locating the resist and determining the pattern shape of the coil pattern;
An insulation treatment step for insulating a part of the cylindrical base material by anodization;
A resist removing step for removing the resist;
The method for producing a cylindrical coil according to claim 1, wherein the cylindrical coil is formed by performing an inner diameter Al removing step of removing aluminum remaining on the entire inner peripheral surface of the cylindrical base material. In the manufacturing method of the cylindrical coil of Claim 6,
The resist patterning step uses a hydrophobic self-assembled monolayer and a hydrophilic self-assembled monolayer to transfer a metal coil pattern onto a transparent and flexible polymer substrate,
Using the polymer substrate as a photomask, the cylindrical substrate made of aluminum coated with a photoresist,
A method of manufacturing a cylindrical coil, wherein the coil pattern is patterned by photolithography.

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