JPS6292748A - Synchronous motor - Google Patents

Abstract

PURPOSE:To improve the starting characteristics by securing a flexible inertial mass body made of the same material in flexible structure to the rotor or rotating shaft of a synchronous motor in which a permanent magnet type rotor is interposed between the stators of two pole windings. CONSTITUTION:To an end of a shaft 2 of a rotor 1 a flexible inertial mass body 10 is fixed with two pieces of washers 11 and 11 and a screw 12. The flexible inertial mass body 10 is, for example, cut off in a sharp angle notched centripetally from the periphery. It is radiatively formed in equal width and the periphery is formed in thick wall. The whole body is integrally constituted with the same material as the rubber, load-containing rubber, or the like. Thus, the moment of inertia can be increased, the starting characteristics improved, and the stable synchronous rotation performed, even if the load and voltage are brought to change.

Description

[Detailed description of the invention] (b) Industrial application fields The present invention relates to a permanent magnet rotor type synchronous motor.

(b) Conventional technology Small-capacity, compact synchronous electric motors with an output of several watts to several tens of watts used as drive sources for household appliances have a stator with salient poles and concentrated winding in order to simplify the structure as much as possible. The rotor is composed of a single cylindrical magnet. However, this type of permanent magnet synchronous motor is not only difficult to start, but also causes fluctuations in rotational angular velocity due to load fluctuations, that is, disturbances, and abnormal vibrations. Furthermore, a decrease in the power supply voltage also causes disturbances, making it impossible to obtain stable starting characteristics and steady-state operating characteristics.

Therefore, in order to solve these problems,
As seen in Japanese Patent No. 92756, an inertia body is attached to a rotor shaft.

That is, as shown in FIG. 9, a viscous friction member 4 made of rubber or the like is fixed to the end of the shaft 2 of the rotor via a spacer 3, and the viscous friction member 4 causes an inertial mass body 5.
are held loosely in the radial and axial directions.

In addition, in the figure, 6 and 7 are the bearings of the shaft 2, 8 is the stator,
9 indicates a coil.

According to this configuration, the inertial mass body 5 acts to suppress the abnormal vibration part of the rotor 1, that is, the angular velocity change, through friction with the viscous friction member 4 due to its inertia, and as a result, the disturbance phenomenon is suppressed, and stable starting is achieved. Characteristic.

Steady operating characteristics can be obtained.

However, in the above-mentioned conventional configuration, the inertial body is constructed by combining and integrating the viscous friction member 4 and the inertial mass body 5, which are made of different materials, resulting in poor productivity and
The configuration becomes complicated and the size increases.

Furthermore, if the lubricant adheres between the viscous friction member 4 and the inertial mass body 5, there is a problem that the inertial mass body 5 immediately spins idly and ceases to function as an inertial body.

(c) Problems to be Solved by the Invention The present invention solves the problems of the prior art described in 2. The purpose is to provide.

(d) Means for solving the problems Therefore, the present invention provides a method for attaching a flexible inertial mass made of the same material such as rubber or lead-containing rubber to the rotor of a synchronous motor or to a shaft integrated with the rotor. It is characterized by the fact that

(e) Since the working inertial body is composed only of flexible inertial mass bodies made of the same material, the structure is simple and productivity is improved, and the area around the electric motor can be made compact. Furthermore, since it is an integral structure rather than a conventional combination structure, problems such as idling do not occur, and it is firmly fixed to the rotor of the synchronous motor or its shaft. The unique inertial force accompanying the circumferential twist generated by the rotation of the flexible inertial body improves the starting and asynchronous rotation (turbulence phenomenon) of the synchronous motor.

(f) Example An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a cross-sectional view of a synchronous motor according to an embodiment of the present invention, in which the same reference numerals as in FIG. 9 indicate the same or corresponding parts. The main difference between the configuration of FIG. 1 and FIG. 9 is that a disc-shaped flexible inertial mass body 10 made of soft non-magnetic material such as rubber or lead-containing rubber is held with a seat plate 11 in between by fixing screws. 12 is the point fixed to the end of the shirt 1-2. In addition, in the figure, 13 indicates a main body case, and 14 indicates a lead wire.

FIGS. 2(a) and 2(b) show a plan view and a side sectional view of the flexible inertial mass body 1o. The notch is cut into an acute angle, the width is the same, and the periphery is made thicker. All parts are integrally made of the same material such as rubber or lead-containing rubber.

By providing the flexible inertial mass body 10 having such a configuration at the end of the shirt [~2], stable starting and asynchronous rotation can be obtained. That is, at the time of starting rotation of the synchronous motor, the irregular rotation in the A state (during asynchronous rotation) is due to the balance between the reluctance torque of the rotor 1 and the excitation torque of the stator 8 and coil 9. Therefore, by fixing the flexible inertial mass body 10 to the end of the shaft 2 as in this embodiment, the flexible inertial mass body 10 has an inertial mass due to the torsion and deflection of its member structure for two rotational vibration movements. By acting as an effective body and acting on the rotor 1 through the shaft 2, it changes the torque balance described above and leads the rotor 1 to completely synchronous rotation. Further, in the synchronous rotation state, the flexible inertial mass body 10 naturally deforms and rotates in a state where the inertial force is minimized, so that the load-like action has almost no effect.

In addition, this flexible inertial mass body 10 is not made of a combination of different materials as in the past, but is integrally formed using the same material, which simplifies the configuration and improves productivity, and the area around the synchronous motor is also compact. Finished with. Furthermore, the conventional problem of loss of inertia due to adhesion of lubricant is eliminated.

FIG. 3 shows a second embodiment of the present invention.
Figure a) is a plan view thereof, and figure (b) is a side sectional view thereof.

Instead of forming eight thick sections as shown in FIG. 2, the flexible inertial mass body 10 is made by making cuts from the periphery toward the center, cutting them at an acute angle, and widening them radially from the center toward the periphery. It may be configured so that Even with this configuration, the same effects as those of the above embodiment can be obtained.

FIG. 4 11 shows a third embodiment of the present invention.

4A is a plan view thereof, and FIG. 2B is a sectional view taken along line r1. The rotor 1 is integrally injection molded with the shaft 2 using a plastic magnetic material.

The injection gate mark 15 generated at this time is formed into a convex shape, and the flexible inertial mass body 1 shown in the embodiment of FIGS. 1 and 2 above is
Shaft in the center of 0 2) Injection gate traces 15 on both sides
Corresponding holes are provided in the holes, and the upper ends of the injection gate traces I5 are welded and fixed.

In this way, the flexible inertial mass body 10 may be fixed to the rotor 1 via the seat plate 11 instead of being fixed to the shaft end, and in this case, the same effect as in the previous embodiment can be obtained. In addition to the effects obtained, the structure around the rotor shaft of the synchronous motor becomes simpler and more compact.

FIG. 5 shows a fourth embodiment of the present invention.

FIG. 5(a) is a plan view thereof, and FIG. 2(b) is a side sectional view thereof. In this embodiment, the flexible inertial mass body 10 is constituted by an elastic metal body having a flexible structure made of the same material, such as a leaf spring.

By fixing the flexible inertial mass body 10 configured in this manner to the end of the shaft 2 or the end face of the rotor 1, the flexible inertial mass body 10 is able to resist the effects of the deflection and expansion/contraction movements of its member structure in response to two rotational vibration movements. By acting as an effective inertial mass body and acting on the rotor 1 through the shaft 2 or directly, it changes the torque balance during the above-mentioned irregular rotation, leading the rotor 1 to completely synchronous rotation.

In addition, when in a synchronous rotation state, the flexible inertial mass body 10 made of an elastic metal body with a flexible structure naturally deforms to a state that becomes a balance point of inertia force and rotates stably, so that load-like effects have almost no effect. It becomes something that does not exist.

When the flexible inertial mass body 10 is directly attached to the rotor 1 made of plastic magnet material, the injection gate trace 15 is used as shown in Fig. 6, and the injection gate trace 15 is shown in Fig. 6(c). The flexible inertial mass body 1° is firmly fixed to the end face of the rotor 1 by forming a concave shape in advance as shown in FIG. can do. In this case, the moment of inertia can be further increased by fixing a weight 16 to the tip of the elastic metal body as shown in FIG. 7, or by increasing the size of the member toward the tip as shown in FIG. , stable rotation can be more reliably obtained during startup and asynchronous rotation.

Note that the moment of inertia may be increased by attaching a plurality of elastic metal bodies.

(G) Effects of the Invention As described above, according to the present invention, since the flexible inertial mass body is attached to the rotor or its rotating shaft, the moment of inertia is increased, and the starting characteristics of the permanent magnet rotor type synchronous motor are increased. In addition, stable synchronous rotation can be maintained even if load fluctuations or voltage fluctuations occur during rotational driving. In addition, the flexible inertial mass body is not composed of two parts made of different materials as in the past, but is composed of a single member made of the same material, so it is reliable and does not lose its function due to idling. In addition, the structure is simple and productivity is improved, and the structure around the rotating shaft is also simplified, making it possible to accommodate compact synchronous motors.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a synchronous motor according to a first embodiment of the present invention, and FIG. 2 is a configuration diagram of its flexible inertial mass body.
) is a plan view thereof, FIG. 3(b) is a side sectional view thereof, FIG. FIG. 4(b) is a side sectional view thereof, FIG. 4 is a configuration diagram of a rotor and a flexible inertial mass body according to a third embodiment of the present invention, and FIG. b) is an I-1 sectional view thereof, FIG. 5 is a configuration diagram of a flexible inertial mass body according to a fourth embodiment of the present invention, FIG. The side sectional view and FIG. 6 are configuration diagrams of a rotor and a flexible inertial mass body according to a fifth embodiment of the present invention. The figure (a) is a plan view thereof, the figure (b) is a sectional view taken along the line ■-■, the figure (c) is a partial sectional view thereof, and FIG. 7 is a flexible inertia according to a sixth embodiment of the present invention. A diagram of the configuration of a mass body. The figure (a) is a plan view thereof, and the figure (b) is a side sectional view thereof. FIG. 8 is a configuration diagram of a flexible inertial mass body according to a seventh embodiment of the present invention, in which FIG. 8(a) is a plan view thereof, FIG. 8(b) is a side sectional view thereof, and FIG. FIG. 2 is a cross-sectional view of a synchronous motor. DESCRIPTION OF SYMBOLS 1... Rotor, 2... Shaft, 10... Flexible inertial mass body, 11... Seat plate, 12... Fixing screw. 15... Injection gate remains, 16... Weight. Figure 1 Figure 2 (a) (b) Figure 3 (a) (b) Figure 4 (a) (b) Figure 5 (a) (b) Figure 6 (a) (b) Figure 7 Figure (a) (b) Figure 8

Claims (7)

[Claims] (1) In a synchronous motor in which a permanent magnet rotor is interposed between a two-pole winding stator, a flexible inertial mass made of the same flexible material is fixed to the rotor or its rotating shaft. A synchronous motor featuring: (2) In claim 1, the flexible inertial mass body is made of a viscous material and is formed into a disc shape that radially spreads from the center in the circumferential direction with the same width, and
A synchronous motor characterized by having a thick peripheral portion. (3) Claim 1, characterized in that the flexible inertial mass body is formed of a viscous material into a disc shape that gradually widens radially from the center in the circumferential direction. synchronous motor. (4) A synchronous motor according to claim 1, wherein the flexible inertial mass body is made of an elastic metal body formed to be deformable in the rotational direction. (5) A synchronous motor according to claim 4, characterized in that a weight is attached to the tip of the elastic metal body. (6) A synchronous motor according to claim 4, characterized in that the elastic metal body is configured to become wider toward its tip. (7) A synchronous motor according to claim 4, characterized in that a plurality of the elastic metal bodies are attached.