RU2040101C1 - Electric motor - Google Patents

Abstract

FIELD: electric engineering. SUBSTANCE: device which is excited by permanent magnet 7 has rotor 2 without winding, stator 1 which has Y-shaped poles 4. Permanent magnet 7 is located in slot of pole 4. Cross-section of slot cover 8 varies from stator periphery to its center. The thinnest part of cover is displaced relative to slot axis. EFFECT: increased functional capabilities. 2 cl, 1 dwg

Description

 The invention relates to electrical engineering, and more specifically to single-phase electric machines for household appliances, for example for vacuum cleaners.

 Known single-phase synchronous jet engine containing a stator core assembled from plates with a winding in the form of two coils forming the same adjacent poles. The rotor, the core of which is also composed of plates, rotates inside the stator. Poles divided into groups form closed magnetic circuits. Magnetic cores of individual poles are limited by the contours of neighboring groups (Russian Railways. Inventions of the world. N 13, 1990. Issue 132; EPO patent N 0343845, class N 02 K 19/06, 05.27.88).

 The disadvantage of this engine is the lack of a guaranteed starting torque.

 Known single-phase induction motor driven by permanent magnets, containing gear magnetic circuits of a windingless rotor and stator, made with poles and winding (ed. St. USSR N 465698, class N 02 K 19/06, published. 1975).

 The disadvantage of this engine, taken as a prototype, is the poor use of the active volume, since the stator magnetic circuit is made of two halves and has an additional tooth for fixing the rotor in the starting position.

 The invention is directed to reducing the size and weight of an electric machine.

 To this end, in an electric machine with equal gear divisions, excited from permanent magnets, containing a windingless rotor, a stator with a Y-shaped poles, the teeth of which are connected by a jumper, and a winding located in the grooves between the poles, according to the invention, the permanent magnets are inserted into the grooves of the poles, and jumpers over these grooves are made with a variable cross-section, and its narrowest part is offset relative to the axis of the groove.

 In the placement sectors of the first jumpers, additional jumpers can be made, the location of which is not associated with the axes of the grooves.

 In contrast to the prototype, the stator magnetic circuit in the proposed machine is made of one part, the magnets are placed in grooves free of winding, which reduces the dimensions of the stator magnetic circuit, and the jumper connecting the pole teeth with a variable cross section reduces the mass of the magnetic circuit. In addition, the variable cross-section allows you to provide the starting position of the rotor relative to the stator, which is necessary for starting conditions, due to the displacement of the axis of the magnetic flux of the permanent magnet.

 The drawing shows an electric machine, cross section.

 The electric machine contains a stator 1 and a rotor 2. On the stator are coils 3 that span the poles 4. The poles are Y-shaped in the form of two teeth 5, 6. Between the teeth 5 and 6 in the grooves of the poles 4, free from winding coils 3, Permanent magnets are placed 7. The polarity of the permanent magnets is consistent with the polarity of the poles 4. The teeth 5 and 6 are connected by jumpers 8 and 9.

 When de-energized winding 3 under the action of a synchronizing moment from the permanent magnets 7, the rotor 2 occupies the starting position. In this position, the magnetic resistance of the magnetic system with respect to the permanent magnets is minimal. Due to the variable cross-section of the jumper 8, the axis of the magnetic flux of the permanent magnet is shifted relative to the axis of the groove between the teeth 5 and 6 to the position in which the starting moment of the machine is provided.

 When a unipolar current pulse is supplied to the winding 3, magnetic forces of attraction of the teeth of the rotor to the teeth of the stator arise. Under the action of the torque, the rotor begins to rotate in the direction of increasing the cross section of the jumper 8. The current flows in the winding 3 until the rotor reaches an angular position in which the axis of the rotor tooth coincides with the axis of the stator tooth (this position is shown in the drawing). With further rotation of the rotor due to the accumulated kinetic energy, the winding 3 should be de-energized until the axis of the rotor tooth coincides with the axis of the groove of the stator pole 4. The next current pulse increases the frequency of rotation of the rotor and thus the engine gradually enters the specified operating mode. Such winding power provides engine starting and unidirectional rotation of the rotor.

 The positive effect of the permanent magnet fixed in the groove free from the winding and the jumper of variable cross section made over the magnet is due to a decrease in the overall dimensions of the machine and a decrease in its mass. The jumper provides the necessary starting conditions for mixing the axis of the magnetic flux of the permanent magnet in the direction of rotation of the rotor.

Claims (2)

 1. ELECTRIC MACHINE with equal gear divisions, excited from a permanent magnet, containing a winding-free rotor, a stator with Y-shaped poles, the teeth of which are connected by a jumper, and a winding located between the poles, characterized in that the permanent magnet is located in the groove of the pole, and the jumper above this groove, a variable section is made, varying from the periphery to the center of the stator, and its narrowest part is offset relative to the axis of the groove.  2. The machine according to claim 1, characterized in that in the sector of placement of the first jumper an additional jumper is located located on the periphery of the stator.