WO2023171093A1

WO2023171093A1 - Method for manufacturing magnetic wedge

Info

Publication number: WO2023171093A1
Application number: PCT/JP2022/048074
Authority: WO
Inventors: 裕己押田; 裕一木場
Original assignee: Ｔｏｗａ株式会社
Priority date: 2022-03-10
Filing date: 2022-12-27
Publication date: 2023-09-14
Also published as: TW202335826A; JP2023132127A

Abstract

Provided is a method for manufacturing a magnetic wedge by which productivity can be increased. The manufacturing method comprises: a resin molding step in which a plurality of cavities formed in an upper mold and/or a lower mold that are opposite each other and gaps narrower than the depth of adjacent portions of the cavities and formed between the plurality of cavities and between the upper mold and the lower mold are filled with a resin material containing a magnetic powder, and in that state, the resin material is resin molded through compression molding such that a plurality of products are collectively molded; and a resin layer removal step in which a resin layer formed by the resin molds at the gaps is removed.

Description

Method for manufacturing magnetic wedges

The present invention relates to a technique for manufacturing a magnetic wedge.

Patent Document 1 discloses a magnetic wedge for fixing a coil to a slot of a stator (iron core) of a motor. This magnetic wedge has a tapered surface that becomes thinner toward the tip so that it can be easily inserted into the slot of the stator.

The technique described in Patent Document 1 uses so-called injection molding, in which resin is poured into a cavity formed by an upper mold and a lower mold through a gate part, as a method of molding the magnetic wedge.

Utility Model Publication No. 56-116852

In injection molding as described in Patent Document 1, it is difficult to secure a large number of magnetic wedges that can be molded in one resin molding, and there is room for improvement in terms of poor productivity.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for manufacturing magnetic wedges that can increase productivity.

The problem to be solved by the present invention is as described above, and in order to solve this problem, a method for manufacturing a magnetic wedge according to the present invention includes a plurality of magnetic wedges formed on at least one of an upper mold and a lower mold facing each other. A resin material containing magnetic powder is filled into a cavity and a gap formed between the plurality of cavities and between the upper mold and the lower mold and which is narrower than the depth of an adjacent portion of the cavity. The method includes a resin molding step of performing resin molding by compression molding so as to mold a plurality of products at once, and a resin layer removing step of removing the resin layer formed by resin molding in the gap.

According to the present invention, productivity of magnetic wedges can be increased.

(a) A perspective view showing the configuration of a motor using a magnetic wedge according to an embodiment of the present invention. (b) A partially enlarged front view of the motor. (a) A perspective view showing a magnetic wedge. (b) A plan view showing a magnetic wedge. (c) X1-X1 sectional view. FIG. 1 is a front sectional view showing the overall configuration of the resin molding device. The top view which showed the bottom member. FIG. 2 is a front cross-sectional view schematically showing the upper mold, the lower mold, and the resin material to be resin-molded. A flowchart showing a method for manufacturing a magnetic wedge. (a) A plan view schematically showing a molded product. (b) X2-X2 sectional view. (a) A diagram showing unnecessary parts cut in a laser cutting process. (b) A diagram showing unnecessary parts cut in the rotary blade cutting process. The front cross-sectional view which showed the modification in which the recessed part was formed in the upper mold|type. (a) A front sectional view showing how grooves are formed in a molded product by laser processing. (b) A front sectional view showing how the magnetic wedge is broken off.

<Motor 1, magnetic wedge 13>
First, an example of the motor 1 using the magnetic wedge 13 will be described with reference to FIGS. 1 and 2.

The motor 1 includes a cylindrical stator 10 and a rotor 20 arranged inside the stator 10 and rotatable relative to the stator 10. A coil 12 is wound around a slot 11 formed in the stator 10. Further, a magnetic wedge 13 for fixing the coil 12 is arranged in the opening of the slot 11.

As shown in FIG. 2, the magnetic wedge 13 according to this embodiment is formed into a rectangular plate shape. The magnetic wedge 13 is formed into a trapezoidal shape in a longitudinal cross-sectional view, as shown in FIG. 2(c). The magnetic wedge 13 is formed with a tapered portion 13a and a straight portion 13b.

The tapered portion 13a is a portion tapered toward one end in the longitudinal direction of the magnetic wedge 13. In this embodiment, the tapered portion 13a is formed only at one end of the magnetic wedge 13 in the longitudinal direction. In the tapered portion 13a, both side surfaces of the magnetic wedge 13 in the transverse direction are formed in an inclined shape such that they approach each other toward the tip. By forming the tapered portion 13a on the magnetic wedge 13 in this manner, the magnetic wedge 13 can be easily inserted into the slot 11 of the stator 10.

The linear portion 13b is a portion formed in a straight line parallel to the longitudinal direction of the magnetic wedge 13. In this embodiment, a portion of the magnetic wedge 13 other than the tapered portion 13a is formed as a linear portion 13b. In the linear portion 13b, both side surfaces of the magnetic wedge 13 in the transverse direction are formed parallel to each other.

The magnetic wedge 13 is manufactured by mixing and molding, for example, iron-based or iron-silicon-based granular soft magnetic powder and a synthetic resin such as epoxy resin. By including the soft magnetic powder in the resin in this manner, the magnetic wedge 13 having magnetism can be formed. By using the magnetic wedge 13 having magnetism in the motor 1, it is possible to suppress the occurrence of uneven magnetic flux density, and it is possible to improve the efficiency of the motor 1.

<Resin molding device 100>
Next, an example of the resin molding apparatus 100 used for manufacturing the magnetic wedge 13 will be described.

The resin molding apparatus 100 shown in FIG. 3 is an apparatus capable of resin molding using a compression molding method. The resin molding apparatus 100 mainly includes a mold 110 (a lower mold 110D and an upper mold 110U), a mold clamping mechanism 120, and the like.

The mold 110 is composed of a lower mold 110D and an upper mold 110U, and forms a cavity C for molding the resin material R.

The lower mold 110D mainly includes a lower mold base member 111, a bottom member 112, a side member 113, an elastic member 114, and the like.

The lower die base member 111 supports a bottom member 112, a side member 113, etc., which will be described later.

The bottom member 112 shown in FIGS. 3 to 5 forms the bottom of the cavity C. The bottom member 112 is formed into a rectangular shape in plan view. The bottom member 112 is formed to have an appropriate vertical width. The bottom member 112 is placed on the upper surface of the lower die base member 111.

As shown in FIGS. 4 and 5, a plurality of recesses 112a corresponding to the shape of the magnetic wedge 13 are formed on the upper surface of the bottom member 112. Specifically, the recess 112a is formed into a rectangular shape in plan view, similar to the outer shape of the magnetic wedge 13. Further, one longitudinal end portion of the recessed portion 112a is formed into a tapered shape corresponding to the tapered portion 13a of the magnetic wedge 13. A plurality of recesses 112a are formed in a state in which they are aligned in the front-rear direction and the left-right direction. A slight gap is formed between adjacent recesses 112a. A cavity C for molding the magnetic wedge 13 is defined by this recess 112a and an upper die 110U, which will be described later. Note that in FIGS. 3 and 5, the recessed portion 112a is illustrated in an exaggerated manner for convenience of explanation.

The side member 113 shown in FIG. 3 surrounds the bottom member 112 from the side. The side member 113 is formed to have an appropriate vertical width. The side member 113 mainly includes a hollow portion 113a.

The hollow portion 113a is formed to vertically penetrate the center of the side member 113. The hollow portion 113a is formed into a rectangular shape in plan view. The hollow portion 113a is formed in a shape that generally matches the outer shape of the bottom member 112 in plan view.

In this way, the side member 113 is formed into a frame shape that is rectangular in plan view. The bottom member 112 is arranged in the hollow portion 113a of the side member 113. The side member 113 is placed on the upper surface of the lower die base member 111 via an elastic member 114, which will be described later. The upper surface of the side member 113 is located above the upper surface of the bottom member 112.

The elastic member 114 is arranged between the side member 113 and the lower die base member 111. The elastic member 114 is formed of, for example, a compression coil spring that can be expanded and contracted up and down.

Note that suction holes (not shown) for sucking and holding the release film F are appropriately formed on the upper surface of the lower mold 110D (bottom member 112 and side member 113). By applying negative pressure to this suction hole using a vacuum pump or the like (not shown), the release film F can be suctioned and held.

The upper mold 110U is formed to have an appropriate vertical width. The bottom surface of the upper mold 110U is formed into a flat surface with no irregularities. Adsorption holes (not shown) for adsorbing and holding the release film F are appropriately formed on the bottom surface of the upper mold 110U. By applying negative pressure to this suction hole using a vacuum pump or the like (not shown), the release film F can be suctioned and held.

The mold clamping mechanism 120 moves the lower mold 110D up and down to perform mold clamping, mold opening, etc. The mold clamping mechanism 120 mainly includes a base 121, a drive mechanism 122, and the like.

The base 121 supports the mold 110 and the like. The base 121 is arranged below the mold 110 (lower mold 110D).

The drive mechanism 122 is for raising and lowering the lower mold 110D. As the drive mechanism 122, a ball screw mechanism, a hydraulic cylinder, a toggle mechanism, etc. can be used. The drive mechanism 122 is arranged between the base 121 and the lower die base member 111.

Note that the operations of each part of the resin molding apparatus 100 described above are appropriately controlled by a control device (not shown).

<Method for manufacturing magnetic wedge 13>
Next, an example of a method for manufacturing the magnetic wedge 13, which is a resin molded product, will be described.

As shown in FIG. 6, the manufacturing method of the magnetic wedge 13 according to the present embodiment mainly includes a film arrangement step S10, a carrying-in step S20, a mold-clamping step S30, a resin molding step S40, a mold-opening step S50, a carrying-out step S60, and a resin It includes a layer removal step S70. Below, they will be explained in order.

The film placement step S10 is a step of placing a release film F (see FIG. 3) on the lower mold 110D and the upper mold 110U.

Specifically, in the film arrangement step S10, two release films F are carried into the mold 110 by a predetermined conveyance device. The two release films F are adsorbed and held on the upper surface of the lower mold 110D and the bottom surface of the upper mold 110U, respectively. Thereby, the release film F is arranged so as to follow the shape of the upper surface of the lower mold 110D and the bottom surface of the upper mold 110U.

Note that it is possible to place the release film F on both the lower mold 110D and the upper mold 110U first, and it is also possible to place the release film F on both the lower mold 110D and the upper mold 110U at the same time. It is.

After the release film F is adsorbed by the lower mold 110D and the upper mold 110U, the process moves from the film arrangement step S10 to the carrying-in step S20.

The carrying process S20 is a process of carrying the resin material R into the mold 110.

Specifically, in the carrying-in step S20, the resin material R is carried into the mold 110 by a predetermined conveying device. The resin material R is accommodated within the lower mold 110D (inside the side member 113). Note that as the resin material R, resins in various states can be used, such as solid powder resin (including granular resin) and liquid resin. Further, the resin material R contains iron-based or iron-silicon-based granular soft magnetic powder.

After the import of the resin material R is completed, the process moves from the import process S20 to the mold clamping process S30.

The mold clamping process S30 is a process of closing (clamping) the mold 110 (lower mold 110D and upper mold 110U).

Specifically, in the mold clamping step S30, first, a heating mechanism (not shown) provided in the lower mold 110D melts the resin material R accommodated in the cavity C if it is in a solid state, and melts it if it is in a liquid state. If so, the viscosity will be lowered. Next, by driving the drive mechanism 122, the lower die 110D is raised toward the upper die 110U. When the lower mold 110D rises to a predetermined position, the upper surface of the side member 113 comes into contact with the bottom surface of the upper mold 110U, and the lower mold 110D (the space in which the resin material R is accommodated) is closed from above by the upper mold 110U.

Note that when clamping the mold, it is preferable to vacuum the air inside the mold 110 to reduce the pressure. Thereby, air (bubbles) in the resin material R can be discharged.

After the mold clamping is completed, the mold clamping process S30 proceeds to the resin molding process S40.

The resin molding step S40 is a step in which the resin material R is compressed and resin molded.

Specifically, in the resin molding step S40, the drive mechanism 122 is driven to further raise the bottom member 112 of the lower mold 110D toward the upper mold 110U. At this time, since the side member 113 is in contact with the upper mold 110U, it does not rise. That is, the bottom member 112 rises relative to the side member 113.

As shown in FIG. 5, a predetermined gap is provided between the bottom member 112 and the upper mold 110U so that the upper surface of the bottom member 112 of the lower mold 110D and the bottom surface of the upper mold 110U do not come into direct contact. Can be vacated. In this way, a space for molding the resin material R is secured between the upper mold 110U and the lower mold 110D. A gap G1 narrower than the depth of the cavities C is formed between two adjacent cavities C (recesses 112a).

More specifically, the gap G1 is set to be narrower than the depth G2 of a portion of the cavity C formed by the recess 112a adjacent to the gap G1 (a portion immediately adjacent to the gap G1). Further, the gap G1 is set to be larger than the maximum particle size of the magnetic powder contained in the resin material R. The maximum particle size means the largest diameter among the diameters of a single magnetic powder when viewed projectively. For example, for magnetic powder having a maximum particle size of 100 μm, the size of the gap G1 is set to a value larger than 100 μm (for example, 300 μm, etc.).

When the bottom member 112 rises, the resin material R accommodated in the lower mold 110D is pressurized and resin-molded. At this time, the resin material R containing magnetic powder flows between the cavities C through the gap G1, and is evenly filled between the upper mold 110U and the lower mold 110D. Thereby, a homogeneous product (ie, magnetic wedge 13) can be manufactured. By waiting for a predetermined time while the resin material R is pressurized, the resin material R is cured. By molding the resin material R in this way, parts corresponding to a plurality of products (that is, the magnetic wedges 13) are molded at once by the plurality of recesses 112a (cavities C). Furthermore, a resin layer 14 is formed between adjacent magnetic wedges 13 to connect the adjacent magnetic wedges 13 (see FIG. 7). The thickness of the resin layer 14 is formed to be thinner than the thickness of the magnetic wedge 13. Note that, hereinafter, the magnetic wedge 13 and the resin layer 14 that are integrally molded may be referred to as a molded product M.

After the resin material R is cured, the process moves from the resin molding step S40 to the mold opening step S50.

The mold opening step S50 is a step of opening (opening) the mold 110 (lower mold 110D and upper mold 110U).

Specifically, in the mold opening step S50, the drive mechanism 122 is driven to lower the lower mold 110D away from the upper mold 110U. This causes the lower mold 110D to separate from the bottom surface of the upper mold 110U.

After the mold opening is completed, the process moves from the mold opening step S50 to the unloading step S60.

The unloading step S60 is a step of unloading the molded product M from the mold 110. In the unloading step S60, the molded product M is unloaded from the mold 110 by a predetermined conveyance device.

After the molded product M is completely unloaded, the unloading step S60 proceeds to the resin layer removal step S70.

The resin layer removal step S70 is a step in which the resin layer 14 is removed from the molded product M to obtain the magnetic wedge 13, which is a product part. The resin layer removal step S70 includes a laser cutting step S71 and a rotating blade cutting step S72.

The laser cutting step S71 is a step in which a portion of the resin layer 14 adjacent to the tapered portion 13a of the magnetic wedge 13 is removed by laser processing.

Specifically, a portion of the resin layer 14 adjacent to the inclined portion of the tapered portion 13a (the portion inclined with respect to the longitudinal direction of the magnetic wedge 13) is removed by laser processing. In FIG. 8A, unnecessary portions 14a of the resin layer 14 that are cut in the laser cutting step S71 are shown by hatching.

The laser beam used in the laser cutting step S71 is a pulsed laser, and the laser beam emitted from a YAG laser or YVO4 laser is used in a laser beam oscillator, or the laser beam emitted from these is converted into a wavelength by a second harmonic generation (SHG) material. Green lasers can be used to convert. Moreover, by scanning with a scanning optical system, the irradiation area of the laser beam can be changed. The wavelength, output, laser diameter, irradiation time, etc. of the laser beam used in the laser cutting step S71 are determined depending on the material of the resin layer 14 and the size of the resin layer 14 (thickness and size of the portion to be cut, etc.). The layer 14 can be optimized for efficient removal.

After the unnecessary portion 14a is removed by laser processing, the process moves from the laser cutting step S71 to the rotating blade cutting step S72.

The rotary blade cutting step S72 is a step in which the resin layer 14 not removed in the laser cutting step S71 is removed by cutting using a rotary blade.

In FIG. 8(b), unnecessary portions 14b of the resin layer 14 that are cut in the rotary blade cutting step S72 are shown by hatching. The unnecessary portion 14b includes a portion adjacent to the straight portion of the straight portion 13b. Specifically, in the rotating blade cutting step S72, the resin layers 14 formed on both sides of the magnetic wedge 13 in the lateral direction and the resin layers 14 formed on both sides of the magnetic wedge 13 in the longitudinal direction are cut by the rotating blade. removed.

The rotary blade used in the rotary blade cutting step S72 includes a rotary blade (spindle) for cutting various resin molded products (for example, a sealed board in which a board on which a semiconductor chip is mounted is sealed with resin). Can be used.

By removing the resin layer 14 through the laser cutting step S71 and the rotary blade cutting step S72, the molded product M can be separated into a plurality of magnetic wedges 13.

In this way, in this embodiment, a plurality of magnetic wedges 13 can be manufactured by one compression molding. Note that, if necessary, it is also possible to perform a step of post-processing the magnetic wedge 13 (removal of burrs, cleaning, etc.) after the resin layer removal step S70.

As described above, the method for manufacturing the magnetic wedge 13 according to the present embodiment includes a plurality of cavities C formed in at least one of the upper mold 110U and the lower mold 110D facing each other, and between the plurality of cavities C and the A plurality of products ( The method includes a resin molding step S40 of performing resin molding by compression molding so as to collectively mold the magnetic wedge 13), and a resin layer removing step S70 of removing the resin layer 14 formed by resin molding in the gap G1. .
With this configuration, the productivity of the magnetic wedge 13 can be increased. That is, since the plurality of magnetic wedges 13 can be resin-molded by compression molding, the productivity of the magnetic wedges 13 can be improved. Moreover, since the resin material R can flow between the cavities C via the gap G1, a homogeneous magnetic wedge 13 can be manufactured. Further, since the resin layer 14 formed between the cavities C (gap G1) is relatively thin, it can be easily removed in the resin layer removal step S70. Moreover, by employing the compression molding method, equipment can be made more compact compared to other resin molding methods (for example, transfer molding, etc.). Furthermore, compared to other resin molding methods, it is possible to reduce the amount of waste generated during resin molding (improve yield).

Further, the distance between the gaps G1 is larger than the maximum particle size of the magnetic powder contained in the resin material R.
With this configuration, the resin material R can easily flow between the cavities C through the gap G1, so that a homogeneous magnetic wedge 13 can be manufactured.

Further, a tapered portion 13a is formed in the magnetic wedge 13 in a tapered shape toward one end in the longitudinal direction, and in the resin layer removal step S70, the resin layer 13 adjacent to the tapered portion 13a is is removed by laser processing.
With this configuration, it is possible to suppress the occurrence of burrs in the portion where the resin layer 14 has been removed. Further, the tapered portion 13a, which is difficult to cut with a rotating blade, can be cut relatively easily and precisely.

Further, a linear portion 13b is formed in the magnetic wedge 13 in a straight line parallel to the longitudinal direction, and in the resin layer removal step S70, the resin layer 14 adjacent to the linear portion 13b is rotated. It is removed by cutting using a blade.
With this configuration, the resin layer 14 can be easily removed at low cost.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and appropriate changes can be made within the scope of the technical idea of the invention described in the claims. .

For example, in the present embodiment, an example is shown in which the tapered portion 13a is formed only at one end in the longitudinal direction of the magnetic wedge 13, but the present invention is not limited to this. For example, it is also possible to form tapered portions 13a at both longitudinal ends of the magnetic wedge 13, respectively. In addition, the shape of the magnetic wedge 13 can be changed arbitrarily.

Further, in this embodiment, an example is shown in which a plurality of recesses 112a are formed on the upper surface of the bottom member 112 in a state in which they are aligned in the front-back direction and the left-right direction (see FIG. 4). method) and number can be changed arbitrarily.

Further, in this embodiment, an example is shown in which the cavity C is defined by the recess 112a formed in the bottom member 112 and the bottom surface (plane portion) of the upper mold 110U, but the method for defining the cavity C is not limited to this. It is not possible to change it arbitrarily. For example, as shown in FIG. 9, it is also possible to form a recess 110a corresponding to the magnetic wedge 13 on the bottom surface of the upper die 110U, and define a cavity C by the recess 112a and the recess 110a. Furthermore, the shapes of the

recesses

112a and 110a can be arbitrarily changed depending on the shape of the product.

Further, in this embodiment, the gap G1 (see FIG. 5) is set to be larger than the maximum particle size of the magnetic powder contained in the resin material R, but the gap G1 can be set arbitrarily. It is possible to change. For example, it is also possible to set the size of the gap G1 to be twice or more, three times or more the maximum particle diameter of the magnetic powder. It is also possible to set the size of the gap G1 based on the average particle size of the magnetic powder. For example, it is also possible to set the size of the gap G1 to be twice or more, three times or more the average particle diameter of the magnetic powder.

Further, in this embodiment, an example was shown in which the resin material R is carried in after placing the release film F on the lower mold 110D and the upper mold 110U (see FIG. 6), but the release film F placed on the lower mold 110D is It is also possible to place the resin material R on top and then place the release film F together with the resin material R on the lower mold 110D. In this case, after being placed on the lower mold 110D, it is possible to adsorb the release film F with the resin material R placed above. Alternatively, the release film F may be placed on the upper mold 110U after the release film F is placed on the lower mold 110D, or the release film F may be placed on the lower mold 110D after the release film F is placed on the upper mold 110U. It is also possible to arrange the release film F on the lower mold 110D and the upper mold 110U at the same time.

Furthermore, in the present embodiment, an example is shown in which the resin layer 14 is removed by laser processing and cutting using a rotating blade in the resin layer removal step S70, but the present invention is not limited to this. For example, it is also possible to remove the resin layer 14 only by laser processing or only by cutting using a rotating blade. It is also possible to remove the resin layer 14 by press working using a cutting die. Further, after holding the product part (magnetic wedge 13) and bending it at the resin layer 14 part to break the boundary part of the resin layer 14, scrape the surface of the magnetic wedge 13 with an appropriate tool (such as a scraper) to make the resin layer. It is also possible to perform a finishing process to remove 14. In this way, various processing methods can be used to remove the resin layer 14, and it is also possible to apply a combination of a plurality of processing methods.

Hereinafter, a modified example of the resin layer removal step S70 will be specifically described.

In the resin layer removal step S70 according to this modification, when removing the unnecessary portion 14b (see FIG. 8(b)), grooves 14c are first formed in the resin layer 14 by laser processing (see FIG. 10(a)). ). For example, the groove 14c is formed in the resin layer 14 adjacent to the linear portion 13b of the magnetic wedge 13 so as to extend parallel to the longitudinal direction of the magnetic wedge 13. By forming the grooves 14c, the thickness of the resin layer 14 is further reduced.

Next, the product parts (magnetic wedges 13) located on both sides of the groove 14c are held and bent along the groove 14c. As a result, stress is concentrated in the thin groove 14c portion of the resin layer 14, and the magnetic wedge 13 can be broken off along the groove 14c (see FIG. 10(b)). At this time, if unnecessary resin layer 14 remains on magnetic wedge 13, it is also possible to perform a finishing process to remove resin layer 14 by scraping the surface of magnetic wedge 13 with an appropriate tool (such as a scraper). be. Further, by adjusting the output of the laser beam, etc., it is also possible to make adjustments so that the resin layer 14 does not remain on the broken-off magnetic wedge 13. With this configuration, finishing processing becomes unnecessary, and the productivity of the magnetic wedge 13 can be further improved.

As described above, in the method for manufacturing the magnetic wedge 13 according to the present modification, the magnetic wedge 13 is formed with the linear portion 13b that is formed in a straight line parallel to the longitudinal direction, and in the resin layer removal step S70. , a groove 14c is formed in the resin layer 14 adjacent to the linear portion 13b by laser processing, and the resin layer 14 is removed by folding the resin layer 14 along the groove 14c.
With this configuration, the resin layer 14 can be removed relatively easily, and the productivity of the magnetic wedge 13 can be improved.

13 Magnetic wedge 13a Tapered portion 13b Straight portion 14 Resin layer 14c Groove 110U Upper mold 110D Lower mold

Claims

a plurality of cavities formed in at least one of an upper mold and a lower mold facing each other; and a plurality of cavities formed between the plurality of cavities and between the upper mold and the lower mold, the depth of which is deeper than the adjacent portions of the cavities; A resin molding process in which resin material containing magnetic powder is filled into a narrow gap and resin is molded by compression molding so as to mold multiple products at once;
a resin layer removing step of removing a resin layer formed by resin molding in the gap;
A method of manufacturing a magnetic wedge, including:
The interval between the gaps is larger than the maximum particle size of the magnetic powder contained in the resin material.
A method for manufacturing a magnetic wedge according to claim 1.
The magnetic wedge is formed with a tapered portion that is tapered toward one end in the longitudinal direction,
In the resin layer removal step, the resin layer adjacent to the tapered portion is removed by laser processing.
A method for manufacturing a magnetic wedge according to claim 1 or 2.
The magnetic wedge has a linear portion formed in a straight line parallel to the longitudinal direction,
In the resin layer removal step, the resin layer adjacent to the linear portion is removed by cutting using a rotating blade.
A method for manufacturing a magnetic wedge according to any one of claims 1 to 3.
The magnetic wedge has a linear portion formed in a straight line parallel to the longitudinal direction,
In the resin layer removal step, a groove is formed in the resin layer adjacent to the linear part by laser processing, and the resin layer is removed by folding the resin layer along the groove.
A method for manufacturing a magnetic wedge according to any one of claims 1 to 3.