JPH04355637A - Thin coil - Google Patents

Abstract

PURPOSE:To get a thin coil which secures the space factor of a coil, which affects the performance of a motor, 80% or more and facilitates the disposition and the connection of the coil, and also facilitates the arrangement and the connection of FG patterns. CONSTITUTION:A plurality of recesses in which to insert and arrange a plurality of coils are made in a substrate 8 consisting of molded resin, and patterns 7 for coil connection are arranged on the inner faces of these recesses 4, and a coil is arranged in each recess 4. The coil can be made by winding a copper foil through an insulating film and cutting it crosswise in specified thickness and providing a terminal at the periphery. The coil may be inserted in each recess of the substrate and may be united with the substrate.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin coil, and is applicable to, for example, a surface-facing motor.

0002

[Prior Art] As shown in FIG. 7, a conventional thin coil used in a common surface-facing motor has a plurality of wire-wound coils 16 made by winding a magnet wire a predetermined number of times and arranged circumferentially on a stator substrate 17. Become. It is common to arrange a frequency generator (hereinafter referred to as "FG") coil pattern 15 on the stator board 17 to configure an FG sensor.

[0003] As another example, slice coils or sheet coils may be used. FIG. 8 shows an example of a sliced coil described in Japanese Patent Application Laid-open No. 61-73552, which is formed by integrating the coil 21 and the FG coil 22 by molding and then slicing them as shown by dotted lines. be done. On the other hand, sheet coils are made by patterning the coil by plating or etching, layering it into multiple layers for the required number of coil turns, and then
It is formed by plating a coil pattern.

0004

[Problem to be Solved by the Invention] When forming a coil for a general surface-facing motor as shown in Fig. 7, the magnet wires to be wound have a round cross-sectional shape, and when the coils are wound, gaps are created between the magnet wires. Therefore, there are drawbacks such as a low space factor of the coil and difficulty in connecting the winding terminal and the board.

In the case of a sliced coil as shown in FIG. 8, the space factor of the coil is high, but since the terminals of the coil are only on the front and back sides, the connection part is not visible when soldering to the stator board, making it difficult to connect. . Further, when integrally molded, it is difficult to accurately position the FG pattern 22 in the mold, and there are drawbacks such as difficulty in achieving roundness and coaxiality with respect to the central axis. In addition, sheet coils have the disadvantage that the coil space factor is low (approximately 50%) and sufficient motor performance cannot be obtained.

The present invention has been made to solve these problems, and it is possible to secure a space factor of 80% or more for the coils, which affects the performance of the motor, and to facilitate the arrangement and connection of the coils. It is an object of the present invention to provide a thin coil that is easy to arrange and connect an FG pattern.

[0007]

[Means for Solving the Problems] The present invention forms a plurality of recesses into which a plurality of coils are inserted into a substrate made of molded resin, and arranges a coil connection pattern on the inner surface of the recess, The present invention is characterized in that a coil is inserted into each of the recesses. The coil may be formed by winding copper foil with an insulating layer interposed therebetween and cutting it into rounds to a predetermined thickness, and terminals may be formed on the outer peripheral surface of this coil. This coil may be inserted into a recess in the substrate and integrated with the substrate.

[0008]

[Operation] By simply inserting and arranging the coils into the plurality of recesses in the substrate made of molded resin, each coil can be placed in a predetermined position accurately and reliably. Copper foil wound through an insulating layer is cut into rings, a coil with terminals is made on the outer circumferential surface, and the coil is placed in a recessed part of a molded resin substrate on which a wiring pattern is arranged and integrated. As a result, a thin coil with a high space factor can be obtained, and the terminals of the coil and the pattern of the substrate can be easily connected.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the thin coil according to the present invention will be described below with reference to the drawings. First, an example of a method for manufacturing a single coil will be described. In FIG. 1, a copper foil 2 coated with an insulating resin on one side is wound around a core 1 with an adhesive interposed therebetween. After curing the adhesive between the layers of the wound copper foil 2, the core 1 is pulled out and sliced into a predetermined width (0.4 to 1 mm) to form the coil 3, as shown in FIG. The coil 3 formed by this method is thin and has a high space factor.

Next, an example of a molded resin substrate used in the present invention will be explained. In FIG. 3, a plurality of recesses 4 are formed at regular intervals in the circumferential direction on the upper surface side of an injection molded substrate (hereinafter simply referred to as "substrate") 8 formed of molded resin, and the bottom of each recess 4 is A bonding land 6 is formed in the portion so as to protrude to face the inner circumferential surface of the coil 3. The coil 3 sliced into the above-mentioned predetermined width is attached to each recess 4 by bonding, press-fitting, or the like.

Since the coil 3 described in FIGS. 1 and 2 is formed by wrapping the copper foil 2, the terminals are located on the side surface of the central hole and on the outer peripheral surface. Therefore, when the coil 3 is mounted on the injection molded substrate 8 and wired, a wiring pattern matching the shape of the coil 3 is printed on the substrate 8 in advance. That is, when the coil 3 is inserted into the recess 4 on the substrate 8, the end portion of the outer peripheral surface of the coil 3 touches the outer peripheral surface of the recess 4, and the beginning portion of the winding on the side surface of the central hole of the coil 3 contacts the outer peripheral surface of the recess 4. is a bonding land 6 protruding from the bottom of the recess 4.
be in contact with Therefore, as shown in FIG. 4, when the coil 3 is inserted into the recess 4 of the substrate 8, the terminals of the wiring pattern 7 are printed on the outer peripheral surface of the recess 4 and on the bonding land 6. In FIG. 4, reference numeral 7a indicates a terminal of the connection pattern 7 printed on the bonding land 6, and 7b indicates a terminal of the connection pattern 7 printed on the outer peripheral surface of the recess 4.

With such a wiring pattern, simply by fitting the coil 3 into the recess, the beginning of the winding of the coil 3 will come into contact with the terminal 7a, and the end of the winding of the coil 3 will come into contact with the terminal 7b. After peeling off the insulating coating at the end of the winding, inserting it into the recess 4, and then performing reflow soldering, the connection of the coil 3 is completed, and there is no need for the hassle of connection unlike with conventional sliced coils. FIG. 5 shows the appearance of the thin coil made as described above. In addition, according to the connection pattern of FIG. 4, six coils 3 are connected in a three-phase Y shape.

On the other hand, as shown in FIG. 6, after the coil 3 is inserted into the substrate 8, an FG coil pattern 12 is printed on the back surface of the substrate 8 using Ag or Cu paste. FG
Since the coil pattern 12 can be formed based on, for example, the center hole of the substrate 3, it is easy to obtain the roundness of the FG coil pattern 12 and coaxiality with respect to the inner diameter, and the FG coil pattern 12 can be formed with high precision. It is possible to form Additionally, on the outer peripheral side of the injection molded resin 3, there are three coil power supply terminals 10 for external connection, and two FG output terminals 9.
It is provided by a lead frame, plating, etc.

[0014] The thin coil made as described above is
The coils 3 are disposed face-to-face with a flat rotor magnet, and by switching the energization to each coil 3 according to the rotational position of the rotor magnet, the rotor magnet and the rotor integrated therewith can be rotationally driven. Each coil 3 is energized via a power supply terminal 10. The FG coil pattern 12 generates a signal with a frequency corresponding to the rotational speed of the rotor, and this signal is output from the FG output terminal 9 and used for rotational speed control and the like.

According to the embodiment described above, the coil 3 can be positioned simply by inserting the coil 3 into the recess 4 of the substrate 8 made of molded resin, and the beginning and end of the winding of the coil 3 can be used for coil connection. Terminals 7a and 7b of pattern 7
Since the coils 3 can be opposed to each other, the arrangement and wiring of the coils 3 can be simplified, and the coils 3 can be positioned accurately and reliably. Further, the FG coil pattern 12 can be printed on the substrate 8 while the coil 3 is integrated with the substrate 8, and since the surface of the substrate 8 on which the FG coil pattern 12 is printed is a flat surface, The FG coil pattern 12 can be easily formed, and its positional accuracy, roundness, and coaxiality can be improved.

[0016] If other motor component parts are mounted in the injection molded board, the board itself can be used as a stator board.

[0017]

[Effects of the Invention] According to the present invention, the coil can be positioned simply by inserting and arranging the coil into the recess of the substrate made of molded resin, and the winding start and winding end of the coil can be made to face the coil connection pattern. Therefore, it is possible to easily arrange and connect the coils, and to position the coils accurately and reliably. Also,
Since the FG coil pattern can be printed on the board while the coil is integrated with the board, the FG coil pattern can be easily formed, and its positional accuracy, roundness, and coaxiality can be improved. can.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an example of a coil forming process applicable to the present invention.

FIG. 2 is a perspective view showing another step following the coil forming step.

FIG. 3 is a perspective view showing an example of an injection molded substrate applicable to the present invention.

FIG. 4 is a plan view of the same injection molded substrate.

FIG. 5 is a perspective view showing an embodiment of a thin coil according to the present invention.

FIG. 6 is a perspective view showing the same thin coil turned over.

FIG. 7 is a plan view showing an example of a conventional thin coil.

FIG. 8 is a perspective view showing an example of a slice coil, which is a type of conventional thin coil.

[Explanation of symbols]

2 Copper foil 3 Coil 4 Recessed part 7 Wiring pattern 8　　　　　　　Substrate

Claims (3)

[Claims] 1. A plurality of recesses into which a plurality of coils are inserted and arranged are formed in a substrate made of molded resin, a pattern for coil connection is provided on the inner surface of the recess, and a coil is inserted into each of the recesses. A thin coil characterized by its arrangement. 2. The thin coil according to claim 1, wherein the coil is formed by winding copper foil with an insulating layer interposed therebetween and cutting it into rounds to a predetermined thickness, and having terminals on the outer peripheral surface. 3. The thin coil according to claim 1, wherein the coil is inserted into each recess of the substrate and integrated with the substrate.