JPH0666257U - motor - Google Patents

Abstract

(57) [Abstract] [Purpose] In a small outer rotor type motor used for office automation equipment and the like, the thickness of the insulating film on the coil winding portion of the stator is reduced. In a motor including a winding portion 2 having a slot 3 and a gap between a stator 1 and a rotor formed in a radial direction, an insulating layer 7 is formed only on the winding portion 2 by electrodeposition coating with an insulating material. Since the insulating layer 7 was formed by electrodeposition coating in this way, it was much thinner than the conventional one.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an outer rotor type motor used for driving a floppy disk or a hard disk in an office automation equipment, for example.

[0002]

[Prior art]

 This type of motor is subject to restrictions in external dimensions both in the radial direction and the thickness direction, and a sufficiently large rotational force is required on the other surface. In order to obtain a large rotating force, the length of the coil wound around the winding portion of the stator must be increased, but the length of the coil wound portion of the stator is small, so the length is sufficient. The current situation is that it cannot be obtained.

Since the winding of the coil cannot be performed directly on the core of the winding portion, the surface of the winding portion is subjected to insulation treatment. In the conventional insulation treatment, a plastic molded product (bobbin) is attached to the winding part of the stator, a magnet wire to be a coil is wound on it, and powder coating is applied to the surface of the winding part. In some cases, the powder coating is applied to form an insulating layer, on which the magnet wire is wound.

FIG. 3 shows a stator of an outer rotor type motor. As shown in FIG. 5, the stator 1 is formed by stacking a large number of core materials to a predetermined thickness. In the illustrated one, eight winding portions 2 and a predetermined slot 3 are provided. It is formed radially. The outer end portion 4 of the winding portion 2 is larger than the winding portion 2 in the circumferential direction. The central portion of the stator 1 is formed with a large circular hole 5. A coil 6 made of magnet wire is wound around the winding portion 2. As shown in FIG. 4, the winding portion 2 is provided with an insulating layer 7, and the coil 6 is wound on the upper surface thereof.

As the insulating layer 7, there are one in which a plastic molded product (bobbin) is mounted and one in which the surface of the winding portion 2 is powder coated. As shown in FIG. 5, the thickness of any of these is large, which has been an obstacle to securing the winding space factor and reducing the winding height of the coil 6 when downsizing the motor.

That is, as the core becomes smaller along with the downsizing of the motor, the insulation coating thickness becomes relatively thick as described above, and it becomes difficult to wind a predetermined number of windings. Even with the same number of turns, the length of the winding is long, which causes problems such as increased electrical resistance and increased power consumption. For example, when a plastic molded product or powder coating is used as an insulating coating, the thickness of the film is about 0.3 to 0.5 mm, and if it is wound on this, the winding diameter becomes large. However, there was a problem that the number of coil turns could not be increased.

For this reason, the coil is crushed to reduce the height after winding for the purpose of reducing the height of the coil. However, the coil may be broken, which may cause a problem in quality. There was an inconvenience that it became high.

In the case of powder coating, if a core having a gap in the radial direction is coated on the outer peripheral surface of the stator as well, the coating will cause the stator to have a large diameter. It is desirable to make the air gap between the rotor and stator of the motor as small as possible in consideration of the characteristic efficiency of the motor. However, since there are variations in manufacturing dimensions and roundness of the rotor and stator, the gap length is set to be as small and long as possible.

If the thickness of the coating film on the outer peripheral surface is 0.3 to 0.5 mm, the variation in the thickness of the coating film and the above variation are combined to set the void length. The void length becomes large. This is a huge disadvantage in terms of motor efficiency.

[0010]

The present invention has been made in view of this point, and an insulating material is applied to the slot portion of the core by electrodeposition coating, and the insulating coating thickness is about 0.02 to 0.05 mm. It is an object of the present invention to provide a motor that can reduce the height of the coil while ensuring the winding occupancy in a motor that is extremely thin and miniaturized.

[0011]

[Means for Solving the Problems]

 As a means for solving the above problems, the present invention provides a stator having a slotted core and a motor in which a gap between the stator and the rotor is formed in the radial direction, in which only the winding portion of the stator is made of an insulating material. The structure is such that the insulating layer is formed by applying electrodeposition coating.

[0012]

[Action]

 With such a structure, an extremely thin insulating layer is formed by electro-deposition coating with an insulating material applied only to the winding part of the stator.Therefore, a magnet wire is wound around this to form a coil. In this case, a sufficient number of turns can be obtained without increasing the winding diameter.

[0013]

【Example】

 An embodiment of the present invention will be described below with reference to FIGS. In the present invention, only the winding portion 2 of the stator 1 having the slots 3 is electrodeposited with an insulating material. In order to apply the electrodeposition coating as described above, an insulating tape 8 made of silicon rubber or the like having a size matching the thickness (width) of the stator 1 is attached to the outside of the outer end 4 of the winding portion 2 of the stator 1. In advance, electrodeposition coating is performed in that state. The insulating tape 8 may be a cover. This insulating tape 8 or cover acts as a masking. After painting, the insulating tape 8 or cover is removed.

In the electrodeposition coating, a plurality of large needle-shaped electrodes (not shown) are arranged in contact with the large circular hole 5 formed in the central portion of the stator 1 at an appropriate distance. A voltage is applied between the needle electrode and the stator 1. As a result, an insulating film is formed on a portion of the stator 1 other than the insulating tape 8 or the portion where the cover is attached. A film is formed on the portion where the plurality of needle-shaped electrodes contact each other by this contact.

When the silicon rubber insulating tape 8 or the cover is removed after the electrodeposition coating is completed, there is no insulating film on the outer peripheral surface of the stator core 1 and an insulating layer is formed on the winding portion including the inner peripheral portion of the slot 3. 7 can be painted in the range of 20 to 50 microns. This is one-tenth the thickness of conventional plastic molded products or powder coating as an insulating coating (see Figures 1 and 5).

[0016]

[Effect of device]

 Since the present invention is a motor configured as described above, it is possible to obtain an extremely thin insulating layer in a required portion of the stator, and thus it is possible to suppress the winding height of the coil to be small. Therefore, it is possible to reduce the size of a motor having a large rotational force.

[Brief description of drawings]

1 is a cross-sectional view taken along the line AA of FIG. 2, showing a cross section of an embodiment of the present invention.

FIG. 2 is a front view of a stator that is an embodiment of the present invention.

FIG. 3 is a front view of a conventional stator.

FIG. 4 is a partial cross-sectional view showing the coil of FIG.

5 is a cross-sectional view taken along the line BB of FIG.

[Explanation of symbols]

 1 Stator 2 Winding part 3 Slot 6 Coil 7 Insulation layer

Claims (1)

[Scope of utility model registration request] 1. A stator comprising a core with slots,
A motor in which a gap between the stator and the rotor is formed in the radial direction, wherein an insulating layer is formed by electrodeposition coating of an insulating material only on the winding portion of the stator.