KR100707430B1 - single phase inducing motors - Google Patents

Abstract

The present invention relates to a single-phase induction motor, and in particular, a main winding that generates an alternating magnetic field; An auxiliary winding for generating an auxiliary magnetic field having a phase difference from the alternating magnetic field; The transformer is connected to the main winding and includes a transformer for changing the magnitude of the voltage input to the main winding so that the flux of the alternating magnetic field generated by the main winding is changed, thereby removing the auxiliary lead wire inside the single-phase induction motor. To improve the productivity by simplifying, shortening the production time and reducing the production cost.

Single Phase Induction Motor, Magnet, Transformer, Tap-Change, Shifting

Description

Single phase inducing motors             

1 is a circuit diagram showing a driving circuit of a single phase induction motor according to the prior art;

2 is a cross-sectional view showing a single phase induction motor according to the present invention;

3 is a circuit diagram showing a driving circuit of the single-phase induction motor according to the present invention;

4 is a graph showing a speed-torque characteristic curve of a single phase induction motor according to the present invention.

<Explanation of symbols on main parts of the drawings>

10 housing 20 induction rotor

22: rotor core 24: teeth

26: slot 30: induction rotor

32: rotor core 34: conductor bar

36: end ring 38: inner gap

40: rotating shaft 42, 44: bearing

50: magnet rotor 52: magnet

60: transformer

The present invention relates to a single-phase induction motor, in particular by changing the magnitude of the voltage applied to the induction motor using a transformer to adjust the rotational speed of the induction motor, simplifying the configuration of the induction motor and at the same time multi-step speed change is possible It relates to an induction motor.

In general, unlike three-phase induction motors that naturally generate a rotating magnetic field, single-phase induction motors do not have starting torque because only alternating magnetic fields are generated by the main winding, and the stopped single-phase motors do not rotate themselves.

Such single-phase induction motors are relatively inefficient in terms of performance and cost compared to three-phase induction motors. However, these single-phase induction motors are widely used in devices that require low power, such as households, because of their convenience.

The single phase induction motor has an auxiliary winding in addition to the main winding to generate starting torque, and the starting device for starting the induction motor by itself is divided into a divided phase starting type, a shading coil type, a condenser starting type, and a rebound starting type according to the type. .

1 is a circuit diagram showing a driving circuit of a single phase induction motor according to the prior art.

As shown in FIG. 1, the driving circuit of the single phase induction motor according to the related art is located at a spatially appropriate angle with the main winding Lm1 for generating an alternating magnetic field in the single phase induction motor, and the main winding Lm1. An auxiliary winding Ls1 for generating an auxiliary magnetic field to become an elliptical rotating field, an advance capacitor C1 connected in series with the auxiliary winding Ls1, and a tap winding for changing flux of the main winding Lm1; And a switch for tap-changing the tap winding Lc1.

The single phase induction motor further includes a tip protect to prevent the single phase induction motor from being overloaded.

Looking at the operation of the prior art configured as described above are as follows.

As shown in FIG. 1, when AC power V1 is applied between nodes A and B, the switch is connected to any one side of the tap winding Lc1, that is, nodes a, b, and c, and the induction motor Satisfies the following equation.

V = 4.44 * f * Φ * N

Where V is the magnitude of the voltage applied to both ends of the stator winding of the single-phase induction motor, f is the frequency of the applied power, Φ is the flux generated in the single-phase induction motor, N is the number of turns of the winding wound on the stator do.

Therefore, if the magnitude of the AC power supply is V1 and the frequency of the power supply is constant at 60 Hz, the flux and the number of turns are in inverse proportion to each other.

In this case, when the switch is connected to the first auxiliary lead wire in which the node a is located, the number of turns N of the winding wound on the stator and the current is substantially maximized, so that the plus Φ of the single phase induction motor is reduced. As the flux Φ decreases, the rotational speed of the conductive conductive motor becomes smaller.

On the other hand, when the switch is connected to the third auxiliary lead line where the node c is located, the number of turns N of the winding wound around the stator to substantially flow the current becomes minimum, and at the same time the flux Φ of the single phase induction motor is increased. The speed of rotation of the induction motor is increased accordingly.

When the switch is connected to the second auxiliary lead wire where the node b is located, the rotational speed of the medium size is displayed as compared to the case where the switch is connected to the nodes a and c, respectively. Therefore, the speed change of the induction motor is changed by the tap switching of the tap winding. Can be implemented.

However, the induction motor according to the prior art has to wind the tap winding in addition to the main winding in the stator for the speed change, and also has to additionally have an auxiliary lead wire for connecting to the switch at each point of the tap winding for the tap method. The winding operation is complicated.

In addition, as the production cost and work time of the single-phase induction motor increases, the size of the induction motor becomes relatively large, and there is a problem that it is difficult to shift speeds of three or more stages.

The present invention has been made to solve the above problems of the prior art, by applying a tap winding to a limited stator to simplify the configuration of the interior to improve productivity, and to secure enough space inside the stator wound inside The purpose of the present invention is to provide a single-phase induction motor that can improve the durability by preventing the temperature rise of the coil and realize a multi-step speed change.

Single phase induction motor according to the present invention for solving the above problems is the main winding line for generating an alternating magnetic field; An auxiliary winding for generating an auxiliary magnetic field having a phase difference from the alternating magnetic field; It characterized in that it comprises a transformer for supplying to the main winding by transforming the input voltage to a predetermined voltage level so that the flux of the alternating magnetic field is changed.

The single phase induction motor may further include: a stator having a hole formed in the center thereof; An induction rotor connected to a center of rotation and rotatably inserted in the stator; A hollow magnet is positioned between the stator and the induction rotor, and the magnet rotor is rotated on the outer circumferential surface of the rotating shaft to independently rotate the magnet on the outer circumferential surface of the induction rotor.

In addition, the transformer is characterized in that the tap-changing transformer.

In addition, the tap-changing transformer is characterized in that the voltage magnitude is adjusted to at least three stages.

In addition, the transformer is characterized in that provided on the outside of the stator and the rotor of the induction motor.

In addition, the transformer is characterized in that at least one of a mechanical or electronic conversion transformer.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a cross-sectional view showing a single-phase induction motor according to the present invention, Figure 3 is a circuit diagram showing a driving circuit of the single-phase induction motor according to the present invention, Figure 4 is a speed-torque characteristic curve of the single-phase induction motor according to the present invention It is a graph shown.

Single phase induction motor according to the present invention is a motor housing 10 having a predetermined receiving space, as shown in Figure 2, the stator 20 is press-fit fixed to the inner peripheral surface of the motor housing 10, the stator 20 Induction rotor 30 is inserted into the center of the rotatably fixed by the rotating shaft 40, and positioned between the stator 20 and the induction rotor 30, and on the outer peripheral surface of the induction rotor 30 Hollow cylindrical magnet rotor 50 is rotatably fixed independently, and comprises a transformer 60 is connected to the winding coil connected to the induction motor.

The housing 10 is rotatably fixed to the rotating shaft 40, each bearing 42 on both sides.

The stator 20 has a stator core 22 seated and fixed to an inner circumferential surface of the housing 10 as an outer circumferential surface, and a plurality of teeth 24 formed along an inner circumferential surface of the stator core 22 protrudes. A stator coil 28 for applying primary current so that each tooth 24 has a polarity of N or S poles is wound in the slot 26 between the teeth 24 and has a spatially appropriate angle with the stator coil. An auxiliary coil (not shown) is constructed which is wound up to apply a secondary current to form an elliptical rotor field.

The transformer 60 is provided outside the stator 20 and the induction rotor 30 of the induction motor, and the transformer 60 is composed of at least one of a mechanical or electronic conversion transformer.

The induction rotor 30 is die-casted to penetrate and fix the rotating shaft 40 through the center of the rotor core 32 and to allow the plurality of conductor bars 34 to penetrate in the longitudinal direction along the circumference of the rotor core 32. And, the current is applied to the conductor bar 34 consists of end rings 36 formed on both side ends so that the flow in the longitudinal direction is generated.

The magnet rotor 50 has a magnet 52 which freely rotates independently of the outer circumferential surface of the induction rotor 30 at intervals of an inner gap 38, and both side ends of the induction rotor 30. Along the circumference, the magnet 52 is provided with a magnet frame 54 which fixes the magnet 52 to prevent the magnet 52 from being separated from the outer circumferential surface of the induction rotor 30.

Here, the magnet frame 54 is connected to the magnet fixing part 54 which fixes the magnet 52 and the shaft coupling part 56 connected to the rotating shaft 40 and the bearing 44. It is composed of shapes.

Here, briefly showing the driving circuit of the single-phase induction motor according to the present invention, as shown in Figure 3, the main winding (Lm2) for generating an alternating magnetic field to the single-phase induction motor, and the main winding (Lm2) and spatially appropriate An auxiliary winding Ls2 for generating an auxiliary magnetic field so as to be an elliptical rotating magnetic field at an angle, an advance capacitor C2 connected in series with the auxiliary winding Ls2, and a voltage applied to the single phase induction motor; It consists of a transformer 60 for transforming the magnitude V1 into the magnitude of the voltage in the main winding Lm2 to V2.

In addition, the single phase induction motor is configured to further include a tip to prevent the overload of the single phase induction motor on either side of the main winding (Lm2).

Looking at the operation of the present invention configured as described above are as follows.

The single phase induction motor satisfies the following equation.

V = 4.44 * f * Φ * N

Where V is the magnitude of the voltage applied to both ends of the stator winding of the single-phase induction motor, f is the frequency of the applied power, Φ is the flux generated in the single-phase induction motor, N is the number of turns of the winding wound on the stator do.

Therefore, if the frequency of the applied power is 60 Hz, and the number of turns wound on the stator is N, the magnitude (V) and flux (Φ) of the applied voltage are proportional to each other.

Although the magnitude of the voltage applied to the nodes A-B is constant at V1, the magnitude of the voltage applied between the nodes A'-B 'while passing through the transformer 60 is adjusted to V2 in various ways.

That is, when the transformer 60 is adjusted such that the high voltage Vhigh is applied to the nodes A'-B ', the flux Φ increases in proportion to the voltage 60, and when the flux Φ increases, FIG. As shown, the torque of the induction motor is also increased to have an operating area with a large rotation speed.

When the transformer is adjusted so that a low voltage Vlow is applied to the nodes A'-B ', the flux Φ decreases accordingly, and when the flux Φ decreases, the torque of the induction motor also decreases, resulting in a rotational speed. Has a small operable area.

Also, when a medium voltage Vmedium of the above-mentioned voltage is applied to the nodes A'-B ', the rotation speed is eventually obtained as an operation region having a medium magnitude.

If the transformer 60 is a tap-changing transformer, the single-phase induction motor can obtain a stepwise rotational speed, and in this case, the rotational speed can be variously implemented in three or more stages when the voltage magnitude is adjusted to at least three stages. have.

That is, in order to adjust the rotation speed in various ways, it is preferable to provide a transformer for changing the applied voltage V2 in various ways so as to implement the operating region of the motor more variously.

And, as shown in Figure 4, the rotational speed of the single-phase induction motor at the intersection with the operation region according to the magnitude of the voltage of the main winding (Lm2) according to the curve (dotted line) according to the load connected to the single-phase induction motor The speed of rotation is determined.

As such, since the transformer 60 may be externally provided to variously change the flux Φ, the speed of the rotation shaft may be smoothly adjusted even in the single-phase induction motor having the induction rotor and the magnet rotor as shown in FIG. 3. You can do it.

Single phase induction motor according to the present invention configured as described above is provided with a transformer to have a variety of output voltage for the control of the rotational speed, to remove the auxiliary lead wire inside the single-phase induction motor, etc. to simplify the configuration, shorten the production time At the same time, there is an advantage to improve productivity by reducing production costs.

In addition, by securing a sufficient space inside the stator of the single-phase induction motor, there is an advantage that durability is improved by preventing the temperature of the coil wound therein from rising.

In addition, by adjusting the rotational speed by using a transformer, it is possible to implement a multi-step speed change according to the characteristics of the transformer, especially in the case of a single-phase induction motor equipped with a magnet rotor and an induction rotor can be effectively changed. There is an advantage to that.

Claims (6)

A sovereignty line generating an alternating magnetic field; An auxiliary winding for generating an auxiliary magnetic field having a phase difference from the alternating magnetic field; And a transformer for converting an input voltage to a predetermined voltage level so as to change the flux of the alternating magnetic field and supplying it to the main winding. The method of claim 1, The single phase induction motor includes a stator having a hole formed in the center thereof; An induction rotor connected to a center of rotation and rotatably inserted in the stator; An induction motor, characterized in that the hollow magnet is located between the stator and the induction rotor, the magnet rotor is rotated on the outer peripheral surface of the rotary shaft so that the magnet is rotated independently on the outer peripheral surface of the induction rotor. The method of claim 1, The transformer is an induction motor, characterized in that the tap-changing transformer. The method of claim 3, wherein The tap-changing transformer is an induction motor, characterized in that the voltage magnitude is adjusted to at least three stages. The method of claim 1, The transformer is an induction motor, characterized in that provided on the outside of the stator and rotor of the induction motor. The method of claim 1, The transformer is an induction motor, characterized in that at least one of a mechanical or electronic conversion transformer.

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