KR100591612B1 - Dc brush motor having attenuation emi - Google Patents

Abstract

According to the present invention, the brush 320 located on the end bell 310 providing a path for power supply supplies the supplied power to the rotating commutator 330 and is generated in the magnet 350 attached to the frame. A DC brush motor having attenuated electromagnetic noise, including a motor body 300 in which a coil wound around a coil in a magnetic field provides a rotational force through the rotating shaft 360 according to the current supply of the commutator 330. An input side filter unit 110 is connected to an external power line and removes external noise conducted along the power line. An EMI filter unit 140 to which power is applied from the input side filter unit 110 to remove high frequency noise generated from the motor body 300; Power is applied from the EMI filter unit 140, and the noise generated in the motor body 300 is configured to be equally symmetric with the input filter unit 110 around the EMI filter unit 140 in a balanced manner. An output side filter unit 150 which is removed so as not to be discharged through the outside; And a first inner filter 210 and a second inner filter 220 which are attached to the end bell 310 and to which power is applied from the output side filter unit 150, and the brush of the motor body 300. An envelope filter circuit 200 for removing high frequency noise generated between the 320 and the commutator 330 is characterized in that it comprises a.

Description

DC brush motor with attenuated electromagnetic noise {DC BRUSH MOTOR HAVING ATTENUATION EMI}

1 is a graph comparing the EMI regulation requirements for military vehicles and civil vehicles.

2 is a view showing a DC brush motor to which the present invention is applied.

3A is a circuit diagram showing an external filter circuit unit to which the present invention is applied.

Figure 3b is a view showing an external filter circuit portion to which the present invention is applied.

Fig. 4A is a circuit diagram showing an endbell filter circuit to which the present invention is applied.

Figure 4b is a view showing the end filter circuit portion to which the present invention is applied.

5 shows a commutator of the prior art;

6 is a view showing a commutator to which the present invention is applied.

7 is a view showing a vehicle fan equipped with a DC brush motor having attenuated electromagnetic noise of the present invention.

8 is a graph showing the EMI characteristics of the DC brush motor to which the present invention is applied.

<Description of Symbols for Main Parts of Drawings>

100: external filter circuit 110: input side filter

120: first common mode line filter 130: first normal mode line filter

140: EMI filter unit 150: output side filter unit

160: second common mode line filter 170: second normal mode line filter

200: endbell filter circuit 210: first internal filter

220: second internal filter 300: motor body

310: Bell 320: brush

330: commutator 340: rotor

350: magnet 360: rotation axis

The present invention relates to a DC brush motor having attenuated electromagnetic noise. More particularly, the present invention relates to a high frequency generated between a commutator and a brush by using a core wound around a brush motor having a high reliability capacitor, a 3-terminal EMI filter, and a wire. The present invention relates to a DC brush motor having noise attenuated electromagnetic noise by removing noise and attaching a separate balanced symmetric noise filter to the outside to remove noise generated from the motor and incoming noise generated from the outside.

In general, a DC brush motor is composed of a permanent magnet as a stator and a coil as an armature, and generates a rotational force by repulsion and pulling of magnetic force by changing the direction of current flowing through the rotor. Currently, almost all DC brush motors use commutators and brushes to divert this current.

However, due to the mechanical principle of the brush and commutator, the DC brush motor generates sparks due to the reverse electromotive force of the coil due to the change of the polarity of the coil during rotation. do.

Since the electromagnetic noise affects the operation of the device itself or other devices that generate electromagnetic waves, which may cause a malfunction or malfunction of the device, in order to prevent damage caused by electromagnetic waves, each device has to meet international standards. Shielding is essential.

Current countermeasures against electromagnetic noise are to install an electromagnetic wave removal filter on the outside of the frame accommodating the DC brush motor to remove the electromagnetic waves generated between the commutator and the brush of the DC brush motor or to supply power. An EMI filter was connected to the inner end of the assembly to eliminate the electromagnetic noise.

However, it is effective to remove some noise, but still emits a lot of electromagnetic waves in the part of the EMI characteristic, so the noise reduction effect obtained by using a commonly used filter is for the civilian, that is, to satisfy the general EMI characteristic. It is not suitable for the EMI characteristics of military equipment, that is, military equipment.

FIG. 1 is a graph comparing EMI regulations required by military vehicles and civil vehicles. As also shown in the graph, the civil EMI standard (C) shows emission of electromagnetic noise in the frequency range of 30 MHz to 1 GHz. Although regulated, the military EMI standard (M: MIL STD 461C PART8) regulates the emission of a wide range of electromagnetic noise, from low frequencies of 150 KHz to high frequencies of 1 GHz, and lower limits than civil standards.

For equipment that meets the limits of electromagnetic waves, source elimination method that removes source while maintaining the same function, filtering method that attaches filtering device according to type and load size of electromagnetic wave, and electrostatic discharge to prevent leakage of generated electromagnetic wave A shielding method for securing space and a grounding method for diffusing and removing the generated electromagnetic waves to the vehicle body and the ground are used, but there are problems in that expensive components are used and complicated design methods are required.

The present invention has been made to solve the above problems, the object of which is to construct an endbell filter circuit for removing high frequency noise generated between the commutator and the brush in the endbell for power supply of the motor and By attaching a separate symmetrical external filter circuit portion to the outside to provide a DC brush motor having attenuated electromagnetic noise to remove noise generated in the motor and noise coming from the outside.

Brush motor having attenuated electromagnetic noise according to an aspect of the present invention for achieving the above object is to rotate the power supplied with the brush 320 is located on the bell (310) providing a path for power supply The rotor 340, which is supplied to the commutator 330 and wound around the coil in the magnetic field generated by the magnet 350 attached to the frame, rotates through the rotating shaft 360 in accordance with the current supply of the commutator 330. A DC brush motor having attenuated electromagnetic wave noise including a motor body 300, comprising: an input side filter unit 110 connected to an external power line and removing external noise conducted along a power line; An EMI filter unit 140 to which power is applied from the input side filter unit 110 to remove high frequency noise generated from the motor body 300; Power is applied from the EMI filter unit 140, and the noise generated in the motor body 300 is configured to be equally symmetric with the input filter unit 110 around the EMI filter unit 140 in a balanced manner. An output side filter unit 150 which is removed so as not to be discharged through the outside; And a first inner filter 210 and a second inner filter 220 which are attached to the end bell 310 and to which power is applied from the output side filter unit 150, and the brush of the motor body 300. An envelope filter circuit 200 for removing high frequency noise generated between the 320 and the commutator 330 is characterized in that it comprises a.

Preferably, the input side filter unit 110 includes a first common mode line filter 120 for removing common mode noise and a first normal mode line filter 130 for removing normal mode noise, and the output side filter. The unit 150 includes a second common mode line filter 160 to remove common mode noise and a second normal mode line filter 170 to remove normal mode noise, and the input side filter unit 110 and the The output side filter unit 150 is symmetrical to each other, and the EMI filter unit 140 is composed of a sixth three-terminal capacitor (C6) and a seventh three-terminal capacitor (C7), which is a condenser-based EMI filter, to achieve symmetry. It is characterized by.

More preferably, in the first internal filter 210 of the endbell filter circuit 200, the fifth coil L5 and the sixth coil L6 of the Troidal type coiled with wires coated with cores are in normal mode. The thirteenth capacitor C13 and the fourteenth capacitor C14 are connected in a common mode to the other side thereof.

More preferably, the width of each block in the commutator 330 is characterized in that less than 3 mm.

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

Hereinafter, the present invention provides an internal electromagnetic noise generated from a motor by including an symmetrical input side filter portion and an output side filter portion configured as an external filter circuit portion in a frame and connected to the external circuit filter portion to remove high frequency noise. Although a DC brush motor having attenuated electromagnetic noise that removes external electromagnetic noise will be described as a preferred embodiment, the technical idea of the present invention is not limited thereto and can be variously modified and implemented by those skilled in the art. .

2 is a view showing a DC brush motor to which the present invention is applied, FIG. 3A is a circuit diagram showing an external filter circuit unit to which the present invention is applied, FIG. 3B is a view showing an external filter circuit unit to which the present invention is applied, and FIG. 4A is a present invention. Fig. 4B is a view showing an envelope filter circuit portion to which the present invention is applied, Fig. 5 is a view showing a commutator of the prior art, and Fig. 6 shows a commutator to which the present invention is applied. 7 is a view showing a vehicle fan equipped with a DC brush motor having attenuated electromagnetic wave noise of the present invention, Figure 8 is a graph showing the EMI characteristics of the DC brush motor to which the present invention is applied.

As illustrated in FIG. 2, the DC brush motor having the attenuated electromagnetic wave noise to which the present invention is applied may include a motor body 300 and the motor body 300 that generate rotational force to provide rotational power to the outside through the rotation shaft 360. An external filter circuit unit attached to the end bell 310 for supplying power and connected to the end filter filter unit 200 to remove high frequency noise and the external filter circuit unit 200 to perform the filtering function outside the frame. 100).

Referring to Figure 3a in more detail with respect to the external filter circuit 100 according to an embodiment of the present invention,

The external filter circuit unit 100 is connected to the input side of the power line to perform the filtering function, the input side filter unit 110 and the input side filter unit 110 and the EMI filter unit 140 and the filtering function The output side filter unit 150 is connected to the EMI filter unit 140 and has the same configuration as the input side filter unit 110 and is symmetrically connected in balance.

The input side filter unit 110 has a common mode at the other side of the second capacitor T12 connected in parallel to both input power lines and the second coil T2 having one side connected to the twelfth capacitor C12. To the tenth capacitor C10 and the eleventh capacitor C11 connected to the ground, and the ninth capacitor C9 connected in parallel with the tenth capacitor C10 and the eleventh capacitor C11. A third inductor L3 and a fourth configured to be connected to a first common mode line filter 120 for removing common mode noise, and to power lines on both sides connected to the other side of the first common mode line filter 120, respectively. A first normal mode line filter 130 including an inductor L4 and an eighth capacitor C8 connected in parallel on the other side of the third inductor L3 and the fourth inductor L4 to remove normal mode noise. ).

The input side filter unit 110 removes the noise emitted from the outside by the capacitor connected to the ground in the common mode of the second coil in the first common mode line filter 120, the noise conducts the power line to the motor Noise is reduced to prevent reaching the input terminal of the body 300.

In addition, the EMI filter unit 140 is connected to both sides of the power line connecting the sixth three-terminal capacitor (C6) and the seventh three-terminal capacitor (C7) that is the EMI filter of the capacitor system to the other side of the input side filter unit 110 Each is symmetrically connected.

The EMI filter unit 140 attenuates frequency components that cause radiation noise by operations of the sixth third-terminal capacitor C6 and the seventh third-terminal capacitor C7. That is, the EMI filter unit 140 functions to attenuate the frequency of the noise emitted from the motor body 300 that is higher than the frequency of the signal handled by the three-terminal condenser circuit.

In addition, the output side filter unit 150 is connected to the other power line of the EMI filter unit 140, the output side filter unit 150 is the same element corresponding to the position symmetrical with the input side filter unit 110 The first inductor L1, the second inductor L2, the fourth capacitor C4, the second capacitor C2, the third capacitor C3, the first coil T1 and the first capacitor It consists of (C1).

That is, the second common mode line filter 160 symmetrical with the first common mode line filter 120 around the EMI filter unit 140 and the second symmetrical with the first normal mode line filter 130. Since a normal mode line filter 170 is included, the fifth capacitor and the first and second inductors are driven to reduce noise so as not to emit noise generated in the motor body 300 to the power line side.

The actual appearance of the external filter circuit unit 100 having the above configuration is shown in FIG. 3B.

Meanwhile, referring to FIG. 4A, the endbell filter circuit part 200 is attached to the motor side surface of the endbell 310 of the motor body 300 and is connected to both sides of the power line connected to the external filter circuit part 100. The fifth coil L5 and the sixth coil L6 connected in the normal mode, the fifth coil L5 and the sixth coil L6, and the thirteenth capacitor C13 connected to the ground in the common mode on the other side thereof. A third internal capacitor 210 including a first internal filter 210 including a fourteenth capacitor C14 and an EMI filter of a capacitor system connected to a power line to the other side of the first internal filter 210, and A second structure consisting of a sixteenth three-terminal capacitor C16, a seventeenth capacitor C17 connected in parallel to the other side thereof, and an eighteenth capacitor C18 and a nineteenth capacitor C19 connected to ground in a common mode; An internal filter 220 is included.

In this case, the first internal filter 210 includes a thirteenth capacitor C13 and a fourteenth capacitor C14 having the fifth coil L5 and the sixth coil L6 connected to the ground as the low pass filter. It is operated to remove the noise of high frequency component generated by the motor body.

In addition, the fifth coil (L5) and the sixth coil (L6) is formed of a troroidal (troidal) structure that is wound around the wire wire coated on the core material of the magnetic component to improve the performance of the low pass filter.

The endbell filter circuit 200 has a filtering function to remove the high frequency noise generated by the spark from the motor body 300 so as not to be emitted to the outside.

The actual appearance of the endbell filter circuit 200 having the above configuration is shown in FIG. 4B.

Meanwhile, referring to FIG. 2, the motor body 300 includes an end bell 310, a brush 320, a commutator 330, a rotor 340, a magnet 350, a rotation shaft 360, and the like.

The end bell 310 provides a path for supplying power to the motor body 300, and the end bell filter circuit 200 is assembled to the surface facing the motor body 300.

The brush 320 is accommodated in the brush holder fixed to the end bell 310, one side is connected to the power source and the other side is in contact with the commutator 330, to flow a current to the rotating commutator 330 To provide a perturbation contact for supplying current to the commutator 330.

The commutator 330 is applied with a current through contact with the brush 320 and serves to change the flow of current as the poles of the magnetic lines of force change so that the rotor 340 continues to receive force in the same direction.

At this time, the commutator 330 is divided into a plurality of blocks by the grooves formed in the surface, while the commutator of the prior art shown in Figure 5 is composed of a block having a relatively wide width, the commutator 330 of the present invention Each block having a width of about 3 mm or less reduces electromagnetic noise caused by contact between the commutator 330 and the brush 320.

The actual appearance of the commutator 330 having the above configuration is shown in FIG. 6.

The magnet 350 is divided into an N pole and an S pole to maintain a magnetic field, and a magnetic force line is formed.

The rotor 340 is a passage of the magnetic field passing from the N pole to the S pole in the magnetic field generated by the magnet 350 to transmit the force received by the coil, it is formed so that the coil can be wound.

The rotating shaft 360 transmits the rotational movement of the rotor 340 to the object connected to the end.

The DC brush motor having the attenuated electromagnetic wave noise having the configuration as described above can be applied in various ways. FIG. 7 is an example, which is a practical example of a vehicle fan equipped with a DC brush motor having the attenuated electromagnetic noise of the present invention. Show the appearance.

Referring to FIG. 8, the DC brush motor having the attenuated electromagnetic noise of the present invention having the above-described configuration has its full band with respect to MIL-STD-461C PART8 standard value A, whose radiation noise emission amount B is a military standard. It can be seen that the emission noise characteristic is about 10 dB lower over (150 kHz to 1 GHz).

The present invention described above is capable of various substitutions, modifications, and changes without departing from the spirit of the present invention for those skilled in the art to which the present invention pertains. It is not limited to the drawings.

As described above, the DC brush motor having the attenuated electromagnetic noise shown in the present invention comprises a highly reliable capacitor, a three-terminal EMI filter, and a coil wound with a wire wire around the core, which is attached to the end bell. By removing the high frequency noise generated between the commutator and the brush of the motor primarily, the external filter circuit part is composed of separate balanced symmetric noise filters to remove the noise generated from the motor as a secondary The effect is that it can remove even the incoming noise generated from.

Claims (4)

In the magnetic field generated by the magnet (350) attached to the frame and supplied to the rotating commutator 330, the supplied power is supplied to the brush 320 is located on the end bell 310 that provides a path for power supply The coil wound around the rotor 340 is connected to the motor body 300 to provide a rotational force through the rotating shaft 360 in accordance with the current supply of the commutator 330, the external power line is conducted along the power line An input filter unit 110 to remove external noise, and the power is supplied from the input filter unit 110, EMI filter unit 140 to remove the high-frequency noise generated in the motor body 300 In a DC brush motor having attenuated electromagnetic noise, Power is applied from the EMI filter unit 140, and the noise generated in the motor body 300 is configured to be equally symmetric with the input filter unit 110 around the EMI filter unit 140 in a balanced manner. An output side filter unit 150 which is removed so as not to be discharged through the outside; And The brush of the motor body 300 is attached to the end bell 310 and includes a first internal filter 210 and a second internal filter 220 to which power is applied from the output side filter unit 150. And including; and the end filter filter unit 200 for removing the high-frequency noise generated between the commutator 320 and, The input side filter unit 110 includes a first common mode line filter 120 for removing common mode noise and a first normal mode line filter 130 for removing normal mode noise, and the output side filter unit 150. ) Includes a second common mode line filter 160 to remove common mode noise and a second normal mode line filter 170 to remove normal mode noise, and include the input side filter unit 110 and the output side filter unit. 150 are mutually symmetrical, The EMI filter unit 140 is composed of a sixth three-terminal capacitor (C6) and a seventh three-terminal capacitor (C7) that is an EMI filter of the capacitor system to form a symmetry, In the first internal filter 210 of the endbell filter circuit 200, the fifth coil L5 and the sixth coil L6 of the Troidal type wound around the core wire are attached in the normal mode, A DC brush motor having attenuated electromagnetic noise, characterized in that the thirteenth capacitor (C13) and the fourteenth capacitor (C14) are connected in a common mode to the other side thereof. delete delete The method of claim 1, The DC brush motor having attenuated electromagnetic noise, characterized in that the width of each block in the commutator (330) is within 3 mm.

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