JPS5932206Y2 - small synchronous motor - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a small synchronous motor having a structure in which a disc multipolar permanent magnet rotor faces a multipolar stator magnetic pole tooth plate.

The stator magnetic pole tooth plates of conventional small synchronous motors of this type were made by punching from iron plates, but the magnetic pole tooth plates often deformed due to residual stress, which became a problem especially as miniaturization and multipolarization progressed. It's getting thicker.

Therefore, the purpose of this invention is to provide a small synchronous motor that can avoid deformation of the multi-pole stator magnetic pole tooth plates.

FIG. 1 is a side sectional view of an embodiment of a small synchronous motor of this invention.

In the figure, 1 is a cylindrical case made of a magnetic material formed into a tip shape, and 4 is a cylindrical case made of a magnetic material that also constitutes the central magnetic path of the electric motor. have.

Reference numeral 5 denotes an excitation coil wound around a coil frame 6 inserted into the cylindrical case 4.

Reference numeral 2 designates a stator magnetic pole tooth plate formed from a soft magnetic material by punching or photoetching as shown in FIG. 2. As an example, a motor having 36 poles is shown.

Reference numeral 3 denotes a non-magnetic substrate, and as shown in FIG. 3, the stator magnetic pole tooth plate 2 is closely attached to and integrated with the substrate 3. As shown in FIG.

The stator magnetic pole tooth plate 2 can be made from an iron laminated plate in which thin iron plates are laminated on a substrate 3 by photolithography.

In this case, a clad plate is obtained by laminating a plurality of layers of iron plates having different magnetic properties, and this is photo-etched to obtain the optimum magnetic properties.

The stator magnetic pole tooth plate 2 is made by punching out a thin iron plate and attaching it to the substrate 3.
It may also be glued to.

Referring to FIG. 2, the stator magnetic pole tooth plate 2 has an outer peripheral side 2a.
18 stator magnetic pole teeth 2aa, 2ab, . It is connected in 4 places.

Furthermore, stator magnetic pole teeth 2 b a , 2 are arranged at equal intervals from the inner circumferential side 2 b of the stator magnetic pole tooth plate toward the outer circumference 2 a of the stator magnetic pole tooth plate.
b b.

... as the magnetic pole tooth 2 a a s 2 a b y...
The magnetic pole teeth 2ba, 2b
b, ... are integrally connected to the outer peripheral side 2a of the stator magnetic pole tooth plate at several places, and the majority of other magnetic pole teeth are connected to the second
As shown in the figure, it is not connected to 2a.

And stator magnetic pole teeth 2aa, 2ab* with narrow magnetic pole tooth width.
Stator magnetic pole teeth 2ba, 2bb, . . . with wide magnetic pole teeth adjacent to each other in the center line of .
It is separated from the center line by an electrical angle of α.

Wide stator magnetic pole teeth 2b adjacent to each other in the counter-rotational direction to the center line of the stator magnetic pole teeth 2aa, 2ab, .
It is arranged to be separated by an electrical angle β from the center line of a y 2 b b y..., and is designed so that α is considerably smaller than β and the following relationship holds true.

That is, stator magnetic pole tooth 2 b a F 2 b b
The width of r... is the stator magnetic pole! 2aa, 2ab, . By arranging the rotors shown in the figure to face each other and exciting the excitation coil 5 with a commercial power source, a synchronous motor that starts automatically in one direction is obtained.

If it is desired to change the rotation direction, the stator magnetic pole tooth plate 2 shown in FIG. 2 can be turned over.

FIG. 4 is a structural diagram of a disc-shaped rotor 9 used face-to-face with the stator magnetic pole tooth plate 2 having the structure shown in FIG.

In this rotor, a total of 36 magnetic poles, the same number as the number of motor poles, are magnetized in N-8 alternately at regular intervals with an electrical angle of (α+β)/2-1800.

Referring again to FIG. 1, the permanent magnet rotor 9 is assembled so as to face the stator magnetic pole tooth plate 2 with a suitable gap as shown in FIG.

The permanent magnet rotor 9 is fixed to a rotor support base 10, which is fixed to the shaft 8, and is mounted face-to-face with the stator magnetic pole tooth plate 2 with the magnetized surface of the permanent magnet facing inward.

At this time, the air gap between the stator magnetic pole tooth plate 2 and the permanent magnet rotor 9 is set to an appropriate value (
0.3 mm).

Then, by exciting the coil 5 with a commercial power source, the stator magnetic pole tooth plate 2 rotates in a predetermined rotation direction at a synchronous speed.

Here, if there is no backing board 3 for the magnetic pole tooth plate 2, the number of motor poles increases, the stator magnetic pole tooth plate 2 becomes thinner, and each magnetic pole becomes thinner. The stator magnetic pole teeth receive an attractive force due to the strength of the magnetic field,
As the rotor rotates, it vibrates and each magnetic pole tooth generates a buzzer-like noise.

However, in this invention, each magnetic pole tooth is tightly bonded to the substrate, so no buzzer sound is generated, and the phenomenon of deformation of each magnetic pole tooth is eliminated, and the flatness of the magnetic pole tooth plate is improved, which further improves the accuracy of the air gap.

As described above, according to this invention, there is a cylindrical stator, a non-magnetic plate fixed to the end face of this cylindrical stator, and a large number of inner sides fixed to the surface of this non-magnetic plate radially from the center side. The magnetic pole tooth is formed by forming the outer magnetic pole tooth, which enters from the outer circumferential side with a predetermined gap between each inner magnetic pole tooth, and having a width different from that of the inner magnetic pole tooth, and one of which is offset in the direction of rotation. Since it is equipped with a pole stator magnetic pole tooth plate and a multipolar permanent magnet rotor that is provided so as to face the multipolar stator magnetic pole tooth plate, the multipolar stator magnetic pole tooth plate is easily vibrated and deformed. Since it is fixed to a non-magnetic plate, its deformation can be prevented, and there is no rotational noise.

[Brief explanation of the drawing]

Figure 1 is a side sectional view of an embodiment of the small synchronous motor of this invention, Figure 2 is a plan view of its multi-pole stator magnetic pole tooth plate, Figure 3 is a sectional view of the same, and Figure 4 is a multi-pole permanent It is a top view of a magnet rotor. DESCRIPTION OF SYMBOLS 1... Magnetic material cylindrical case, 2... Multipolar stator magnetic pole tooth plate, 3... Substrate, 9... Multipolar permanent magnet rotor.

Claims (1)

[Scope of utility model registration request] A cylindrical stator, a non-magnetic plate fixed to the end face of this cylindrical stator, and a large number of inner magnetic pole teeth fixed to the surface of this non-magnetic plate radially from the center side, and each inner magnetic pole tooth from the outer circumferential side. A multi-pole stator magnetic pole tooth plate in which outer magnetic pole teeth that enter with a predetermined gap between the magnetic pole teeth are formed to have a width different from that of the inner magnetic pole teeth, and one of them is offset in the rotation direction, and this multi-pole A small synchronous motor equipped with a multi-polar permanent magnet rotor that is disposed so as to face the stator magnetic pole tooth roots.