JPS6154854A - Permanent magnet rotor type synchronous motor - Google Patents

Abstract

PURPOSE:To improve the starting action of a synchronous motor by providing a rotor rotatably supported between poles, and composing the rotor of a permanent magnet and a core buried in the magnet, thereby operating an attracting force at the projection of the core at starting time to generate a vibration. CONSTITUTION:An armature winding 14 is not energized, a permanent magnet rotor 11 is opposed at the center of poles to poles 15, 15, and stopped. When a power source is turned ON, and alternating magnetic field is generated between poles 15 and 15. At this time, the average value of the force acted on the rotor 11 is zero, but the projection is always attracted to the direction of the alternating magnetic field at the core 16, and the rotor 11 is accordingly moved counterclockwise. Thus, the direction of N-, S-pole axis of the magnet is displaced from the alternating magnetic field of the stator 13 to act a large repelling or attracting force to the magnet of the rotor 11 to continue the vibration, thereby improving the starting action of the motor.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a small synchronous motor having a permanent magnet as a rotor.

Conventional Structures and Problems Generally, synchronous motors are started using a starting torque based on the principle of an induction motor, but some very small motors do not have a starting torque as shown in FIG. (1)
is a cylindrical permanent magnet rotor magnetized with two poles in a direction perpendicular to 1llll11 (2), and (3) is a stator.

(4) is the armature winding. As is well known, this permanent magnet synchronous motor generates an alternating magnetic field in the magnetic pole parts (5) (5) of the stator (3) by the alternating current voltage applied to the armature winding (4), and the permanent magnet rotor ( 1) Self-starts by generating vibration and increasing it, but it has the problem that starting is inherently poor and this tendency becomes more pronounced as the output increases. There is.

OBJECTS OF THE INVENTION An object of the present invention is to provide a permanent magnet synchronous motor with good starting performance.

Composition of the Invention A permanent magnet rotor type synchronous motor of the present invention includes a stator having magnetic pole sections, an armature winding that excites the stator, and a rotor rotatably supported between the magnetic pole sections. and the rotor is composed of a permanent magnet and an iron core embedded in the permanent magnet, and the iron core is arranged so as to have a protrusion in a direction substantially opposite to the magnetic pole tips of the stator. , is characterized in that at the time of starting, a suction force is applied to the protrusion of the iron core to generate vibration, thereby improving starting.

Description of examples An embodiment of the present invention will be described below with reference to FIG.

(13) is a stator, (14) is an armature winding that excites this stator (13), and (11) is a shaft (12) between the magnetic pole parts (15) of the stator (13). ), in which an iron core (16) is embedded with its protrusion facing in a direction substantially opposite to the magnetic pole tips of the stator (13).

With this configuration, when the armature winding (14) is not energized, the permanent magnet rotor (11) stops with its magnetic pole center facing the magnetic pole portion (15) (15). When the power is turned on, the magnetic pole parts (15) (1,
5) An alternating magnetic field is generated between the two. At this time, the average value of the force acting on the permanent magnets of the permanent magnet rotor (11) is zero, but the protrusions always exert an attractive force on the iron core (16) in the direction of the alternating magnetic field. The magnet rotor (11) moves counterclockwise in response to torque, and the direction of the N-3 magnetic axis of the permanent magnet deviates from the direction of the alternating magnetic field of the stator (13), causing the permanent magnet rotor (11) to move counterclockwise. Since a large repulsive force or attractive force acts on the magnet and the vibration can be sustained, it is possible to improve starting.

As described in the detailed description of the invention, in the permanent magnet rotor type synchronous motor of the present invention, one rotor is composed of a permanent magnet and an iron core embedded in the permanent magnet, and the iron core is connected to the pole tip of the stator. Since the protrusion is disposed in a direction substantially opposite to the synchronous motor, the average value of the torque acting on the rotor at the time of starting is zero in a conventional permanent magnet synchronous motor that is composed of a single permanent magnet. When a permanent magnet synchronous motor is started, a directional torque acts on the iron core embedded in the permanent magnet stator, generating vibration, and even after that, the direction of the permanent magnet and the iron core with protrusions is shifted. It is possible to provide a permanent magnet synchronous motor that can maintain vibration without a dead center of the torque acting on the rotor in a magnetic field and that has improved startability with a simple configuration.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway plan view of a conventional permanent magnet rotor type synchronous motor, and FIG. 2 is a partially cutaway plan view of an embodiment of the permanent magnet rotor type synchronous motor of the present invention. (11)...Permanent magnet rotor, (12)...Shaft, (
13)... Stator, (14)... Armature winding, (1
5)... Magnetic pole part, (16)... Iron core agent Yoshihiro Morimoto Figure 1

Claims (1)

[Claims] 1. A stator having a magnetic pole part, an armature winding that excites this stator, and a rotor rotatably supported between the magnetic pole parts, and the rotor is connected to a permanent magnet and the permanent magnet. A permanent magnet rotor type synchronous motor comprising an iron core embedded in a magnet, and the iron core is arranged so as to have a protrusion in a direction substantially facing the magnetic pole tip of the stator.