JPS6338696Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a device for attaching a stator coil to a stator substrate in a flat type motor.

Before explaining the motor according to the present invention, this type of brushless flat type motor will be explained.

Referring to FIGS. 1 and 2, reference numeral 1 indicates this motor, which is constructed in a flat type. Reference numeral 2 denotes the stator, which is made of a magnetic material and includes a stator substrate 3 which also serves as a heat sink, and a plurality of (four in this example) coil devices 4 attached to the upper surface of the stator substrate 3. This coil device 4 is shown in FIGS.
As shown in the figure, it consists of a flat coil bobbin 5 and a coil 6 wound around the flat coil bobbin 5. 7 is a mounting screw for mounting on the board 3. A rotor 8 is composed of a cup-shaped magnetic yoke 9 and an annular magnet 10 attached to the inner surface of the cup-shaped magnetic yoke 9. The magnetic yoke 9 is attached to the rotating shaft 12 via a connecting member 11,
The above-mentioned rotating shaft 12 is supported by a cylindrical bearing 13 mounted on the stator substrate 3 via a bearing device 14 such as a ball bearing. The flat motor 1 is configured in this way,
The coil device 4 and the magnet 10 are opposed to each other with a small distance between them, and a magnetic circuit is formed which passes through the magnet 10, the stator board 3, and the magnetic yoke 9. Therefore, the rotor 8 is rotated by passing the drive power through the coil device 4 disposed in the passage. Since such a configuration is well known, detailed explanation thereof will be omitted. In this example, a case is shown in which the upper part of the above-mentioned connecting member 11 is configured to also serve as a reel stand. 15 is a chassis, that is, a mounting board for the motor.

Conventionally, in the coil device 4, the thickness i of the bobbin 5 and the thickness h of the coil 6 are equal, and even in the case without a flange, the coil 6 is simply wound on the bobbin 5, and the entire coil 6 is welded with a welding material, or the coil 6 is welded with a wire material. After winding on the bobbin 5 using a heat-fused wire as itself,
It is heat fused. The bobbin 5 is fixed to the stator board 3 by mechanically connecting it using screws 7 or the like.

According to such a conventional configuration, a strong magnetic attraction force generated between the coil 6 and the magnet 10 acts to cause the coil 6 to be separated from the substrate 3, as indicated by the two-dot chain line in FIG. As shown, the coil 6 may float above the substrate 3, or the circumferential end of the coil 6 may be separated from the substrate 3 due to so-called warping of the coil 6. In this state, the heat generated in the coil 6 is effectively transferred to the substrate. In other words, there is a possibility that the heat dissipation effect may be deteriorated. Further, there are other drawbacks such as so-called wobbling during use, or the coil 6 sometimes coming off from the bobbin 5 due to the strong magnetic attraction force.

This invention was taken into consideration in view of the above points,
The motor coil device according to the present invention will be described with reference to FIG. 4 and subsequent figures. Parts corresponding to those in FIG. 3 will be given the same reference numerals and their explanation will be omitted.

That is, in the present invention, when the diameter of the wire itself of the coil 6 is d, as shown in FIG.
The thickness of each part or the diameter of the wire is selected so that the relationship between the winding thickness h of the coil 6 and the thickness i of the bobbin 5 is hi<d.

Furthermore, when attaching the bobbin 5 to the substrate 3, the attachment condition to the substrate 3 is selected so that there is a gap between the bobbin 5 and the substrate 3 based on the above h-i, and the bobbin 5 is attached to the coil 6. Winding surface 5a
As shown in FIGS. 4 and 5, the winding surface 5a is expanded in a tapered shape as it moves away from the substrate 3, or a stepped portion 5b is formed on the winding surface 5a as shown in FIG. It is something to do. Of course, the coil 6 is entirely welded with a melting material, or is wound using a heat-sealable wire and then heat-sealed and solidified. In this case, as shown in FIG. 4, the part of the coil 6 near the center is slightly bent and solidified in advance so that the part near the center of the coil 6 stands out from the board 3 more than the outer peripheral part, and when it is attached to the board 3, the bobbin 5 is is attached so as to be brought strongly close to (but not in contact with) the substrate 3, and a portion closer to the center of the coil 6 can also be brought into contact with the substrate 3 as shown in FIG. Therefore, the entire lower surface of the coil 6 is brought into contact with the substrate 3, and the outer peripheral portion of the coil 6 is also strongly brought into contact with the substrate 3, so that the coil 6 is fixed in close contact with the substrate 3.

According to the present invention described above, since the thickness i of the bobbin 5 is smaller than the thickness h of the coil 6, when the bobbin 5 is attached to the substrate 3, the lower surface of the bobbin 5 does not come into contact with the substrate 3. Therefore, all the pressing force (tightening force by the screw 7) applied to the bobbin 5 is applied to the coil 6, and therefore, the coil 6 can be brought into strong contact with the substrate 3. , the heat generated by the coil 6 is effectively transmitted to the substrate 3, and the heat dissipation effect is increased.

Incidentally, when the coil device 4 is used as shown in FIG. 1, the coil 6
Since a strong magnetic attraction force is generated between the coil 6 and the magnet 10, the coil 6 tends to be separated from the substrate 3. In this case, the coil 6 has a portion close to the bobbin 5, that is, a portion close to the center of the coil 6, which is strongly brought into contact with the substrate 3, but an outer peripheral portion is brought into contact with the substrate 3 with a relatively weaker force than the central portion. become,
Therefore, due to the above-mentioned magnetic attraction force, the outer peripheral portion of the coil 6 is particularly likely to be peeled off.

However, according to the present invention, since the entire coil 6 is configured in advance in a slightly curved shape, when the coil 6 is attached to the substrate 3, the outer circumferential portion of the coil 6 is also close to the center. The coil 6 is brought into contact with the substrate 3 with a strong force similar to that of the coil 6, so that the outer peripheral part of the coil 6 can be prevented from peeling off, and the heat dissipation effect is not impaired. has.

Note that if a thermally conductive adhesive or a thermally conductive insulating material is used between the coil 6 and the substrate 3, the heat dissipation effect can be further enhanced.

Further, according to the present invention, as shown in FIGS. 4 and 5, the winding surface 5a of the bobbin 5 for the coil 6 is expanded in a tapered shape as it moves away from the substrate 3. When attaching to the board 3, no slip occurs between the outer peripheral surface of the bobbin 5 and the inner peripheral surface of the wound coil 6, so that the coil 6 can be reliably attached to the board 3. It is something.

Of course, in FIG. 6, the bobbin 5 has a stepped portion 5b.
is formed, and the entire coil 6 is formed in one piece (solidification), so in this case as well, the fifth
Similar to the case shown in the figure, there is a feature that the bobbin 5 and the coil 6 can be held securely without slipping between them.

Moreover, since the winding surface 5a of the bobbin 5 for the coil 6 expands in a truss-like shape as it goes away from the substrate 3, or forms a stepped portion 5b, the winding surface 5a for the coil 6 is not easily wound on the bobbin 5. The present invention has a feature that the coil 6 can be prevented from detaching from the substrate 3 when it is attached to the substrate 3, and thus the drawbacks of the prior art described at the beginning can be avoided.

Furthermore, in the present invention, since the relationship h-i<d is selected, the coil 6 can be wound on the bobbin 5 without any hindrance.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an example of a coil device for a conventional flat type motor, Fig. 2 is a plan view of its stator, Fig. 3 is a sectional view of a part thereof, and Fig. 4 is a sectional view of a coil device according to the present invention. Exploded sectional view showing an example, No. 5
6 is a sectional view similar to FIG. 5 showing another embodiment, and FIG. 7 is an enlarged sectional view of a portion of FIG. 5. In the figure, 2 is a stator, 3 is a stator board, 4 is a coil device, 5 is a bobbin, and 6 is a coil.

Claims (1)

[Scope of utility model registration request] In a coil device for a flat motor in which a rotor magnet faces a flat coil arranged on a stator board and wound on a bobbin, the wound coil is entirely integrated. and has a slightly curved shape so that a portion near the center thereof is lifted from the substrate more than its outer peripheral portion, the winding thickness of the coil is h, the thickness of the bobbin is i, and the above-mentioned When the diameter of the wire of the coil is d, the thickness of each part or the diameter of the wire is selected so that h-i<d, and when the coil is mounted on the board, the connection between the board and the bobbin is The winding surface of the bobbin with respect to the coil is configured to expand in a tapered shape as it moves away from the substrate, or the winding surface 1. A coil device for a flat type motor, characterized in that a stepped portion is formed in the coil, and the coil is pressed against a substrate via the bobbin.