JP2010035407A - Electric motor, brushless motor, output shaft bearing portion of electric motor, and output shaft bearing portion of brushless motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that countermeasure is required against radio frequency electrolytic corrosion(wavelike wear phenomenon), which may occur at an output shaft bearing portion, even though high efficiency improvement is required for an air-conditioning brushless motor or the like and the PWM driving system is adopted especially. <P>SOLUTION: An inner ring 151a, a tumbling member 151b arranged at a perimeter portion of the inner ring 151a, an outer ring 151c for supporting the tumbling member 151b together with the inner ring 151a, and a sealing plate 151d arranged in contact with the inner ring 151a and the outer ring 151b while covering a side section of the tumbling object 151b are provided. The sealing plate 151d has a conductive sliding portion 151e at least on a portion thereof. The conductive sliding portion consists of two or more conductive thin wire members 151e prepared at least on a portion of the sealing plate 151d. One end of the conductive thin wire member is connected to the sealing plate 151d, and the other end of the conductive thin wire member 151e is put in contact with the inner ring 151a or the outer ring 151c in this constitution. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electric motor and a brushless motor that are mounted on an electric device, for example, an air conditioner, for driving a blower fan.

  For example, a fan motor mounted on an air conditioner for driving a blower fan has recently been required to be highly efficient with energy saving of the air conditioner body. As the fan motor, a high-efficiency brushless motor is often used instead of the induction motor. In many cases, the brushless motor is driven by a pulse width modulation (hereinafter referred to as PWM) inverter.

  In adopting such PWM drive, when high-frequency electric corrosion (hereinafter simply referred to as electric corrosion) of the output shaft support for supporting the motor shaft proceeds, a wavy wear phenomenon occurs and an abnormal sound is generated. There is.

  A conventional brushless motor of this type includes a motor structure described in Patent Document 1, for example. A conventional brushless motor of this type will be described with reference to FIGS. FIG. 3 is a structural cross-sectional view of a conventional brushless motor, and FIG. 4 is a model diagram of the approximate distribution of stray capacitance of the brushless motor shown in FIG.

  In FIG. 3, a stator is formed by molding a stator core 11 around which a stator winding 12 is wound with an insulating resin 13. A rotor 14 is inserted inside the stator through a gap. Two output shaft support portions 15 are attached to the shaft 16 of the rotor 14. The two output shaft support portions 15 are respectively supported by a stator insulating resin 13 and a bracket 17. The rotor 14 can rotate with the shaft 16 supported by two output shaft support portions 15.

  Further, the brushless motor has a built-in printed wiring board 18 on which a drive circuit is mounted, and a brushless motor is formed by press-fitting the bracket 17 into the stator.

JP 2004-242413 A

  However, in the conventional structure of this type of motor, stray capacitances C1 to C7 and the like exist between the components as shown in FIG. 4 because the stator is resin-molded with insulating resin. When the stator winding 12 of such a conventional motor is driven by a PWM inverter, a through current flows through the stray capacitances C1 to C7. As a result, a potential difference occurs between the constituent members, and electrolytic corrosion may occur under certain conditions.

  As a condition where electric corrosion is particularly likely to occur, it may occur when the motor is operated for a long time in a region where the applied voltage is high (for example, a commercial power supply 240V region) at a relatively low temperature and with a small number of revolutions. Are known. An example of the mechanism by which electrolytic corrosion occurs is as follows.

  When the stator winding 12 is driven by a PWM inverter, the stator core 11 to the stator winding 12, the printed wiring board 18, the bracket 17, and the output shaft support portion are passed through the stray capacitances C1 to C7 between the constituent members. 15, a loop-shaped high-frequency circulating current that returns to the shaft 16, the rotor 14, and the stator core 11 is generated.

  At that time, when the oil film of the grease as the lubricant is cut or the oil film thickness becomes thin inside the output shaft support portion 15, a discharge phenomenon due to local dielectric breakdown occurs accordingly, and the output shaft support portion 15 A minute discharge trace is formed on the transfer surface, and this may last for a long time, leading to electric corrosion. The presence or absence of this discharge phenomenon is closely related to C3 or C6 when the voltage is divided by the stray capacitances C1 to C7, that is, the magnitude of the voltage applied to each output shaft support portion 15. Here, Vdc in the figure is a voltage applied to the printed wiring board 18.

  Then, by repeating this electrolytic corrosion phenomenon, the surface of the rolling element of the output shaft support 15 is roughened, and when it becomes wavy, it finally leads to the generation of abnormal motor noise. As an example of a method for reliably preventing this, there is a method of using an output shaft support portion using a ceramic ball which is a non-conductive material between an inner ring and an outer ring of the output shaft support portion.

  However, this ceramic ball output shaft support is very expensive and has not yet been used in mass production.

  Other methods include making the output shaft bearing grease conductive, grounding the stator core, and lowering the PWM drive carrier frequency.

  However, none of these methods are necessarily satisfactory in terms of reliability, cost, quality, and usability, and the fact is that they have not been adopted. As described above, countermeasures against electric corrosion are accompanied by an increase in the cost of the output shaft support, an increase in the material cost of the motor, and a decrease in usability.

  Further, since the stator is resin-molded so as to be covered with insulating resin, the model of the equivalent circuit of the schematic diagram of the stray capacitance approximate distribution of the brushless motor shown in FIG. Based on this recognition, many means for adding an electrical connection path have been proposed so as to obtain an equivalent circuit similar to the equivalent circuit of an electric motor (brushless motor) having a classic configuration. The classic motor (brushless motor) mentioned here means that the stator is not covered with insulating resin, the stator is covered with a metal housing (motor housing), etc., and other components such as brackets Is also an electric motor made of a metal material.

  An equivalent circuit similar to the equivalent circuit of an electric motor (brushless motor) having a classic configuration is, for example, a configuration in which a stator iron core and a bracket are electrically connected, or in the case of having a pair of brackets, the brackets are electrically connected to each other. There are a configuration in which connection is made, and a configuration in which the pair of brackets and the stator are all electrically connected. Each of the configurations is a configuration proposed from the recognition of the problem of making the circuit equivalent to the equivalent circuit of an electric motor (brushless motor) having a classic configuration in which most of the constituent members are made of a metal material.

  Although it is a suppression of the occurrence of electrolytic corrosion by the method of making it equal to the above equivalent circuit, it is a good result, but it is a good result, but it is still a problem in terms of seeking a higher quality electric motor It is hard to say that has been resolved.

  In addition, if the electric motor (brushless motor) of the classic configuration, there is no electric corrosion, it is not so, but high-powered ones such as power generators for power plants and power motors for electric railway vehicles In addition, it is well known that electric corrosion has occurred in the output shaft support portion of an electric motor or the like placed in a high humidity environment. It has also been well known for a long time that the potential difference between the output shaft that generates electrolytic corrosion and a component other than the output shaft is referred to as shaft voltage or shaft current.

  In order to solve the above-described conventional problems, in the first invention, in the electric motor, the output shaft support portion for supporting the output shaft of the motor includes an inner ring, a rolling element disposed on the outer peripheral portion of the inner ring, An outer ring that sandwiches the rolling element with the inner ring, and a seal plate that covers a side portion of the rolling element and is disposed in contact with the inner ring and the outer ring, and a conductive sliding portion is provided on at least a part of the seal plate. It is an electric motor having.

  According to a second aspect of the present invention, in the brushless motor, the output shaft support portion for supporting the output shaft of the brushless motor includes an inner ring, a rolling element disposed on the outer periphery of the inner ring, and the rolling element as the inner ring. The brushless motor includes an outer ring that is pinched and a seal plate that covers a side portion of the rolling element and is disposed in contact with the inner ring and the outer ring, and has a conductive sliding portion at least in part of the seal plate.

  Further, the third invention is a brushless motor having a control circuit portion, wherein an output shaft support portion for supporting the output shaft of the brushless motor includes an inner ring, a rolling element disposed on an outer peripheral portion of the inner ring, An outer ring that sandwiches the rolling element with the inner ring, and a seal plate that covers a side portion of the rolling element and is disposed in contact with the inner ring and the outer ring, and a conductive sliding portion is provided on at least a part of the seal plate. A brushless motor.

  According to a fourth aspect of the present invention, in the brushless motor, a stator winding body in which a winding is wound around a stator iron core insulated with a resin, the stator winding body is molded with an insulating resin, and A stator molded body in which a part of the stator core is exposed, a rotor disposed to face a teeth portion of the stator, an output shaft that is axially attached to a shaft through hole of the rotor, and A pair of output shaft support portions for supporting the output shaft with a rotor interposed therebetween, and one of the output shaft support portions provided at the inner bottom of the exposed portion of the stator of the stator molded body are accommodated. A brushless motor comprising a storage portion of the output shaft support portion and a bracket that stores the other side of the output shaft support portion and is disposed in the opening of the stator molded body, wherein the output shaft support portion is An inner ring, a rolling element disposed on the outer periphery of the inner ring, and the rolling element A brushless motor comprising an outer ring sandwiched between a ring and a seal plate that covers a side portion of the rolling element and is disposed in contact with the inner ring and the outer ring, and having a conductive sliding portion at least in part of the seal plate is there.

  According to a fifth aspect of the present invention, there is provided a brushless motor including a control circuit unit, a stator winding body in which a winding is wound around a stator iron core insulated with a resin, and the stator winding body that is an insulating resin. The stator molded body molded with the above and a part of the stator iron core is exposed, the rotor disposed opposite to the teeth portion of the stator, and the shaft through-hole of the rotor. An output shaft, a pair of output shaft support portions for supporting the output shaft with the rotor interposed therebetween, and an output shaft support provided at an inner bottom portion of the exposed portion of the stator of the stator molded body. A brushless motor comprising: a storage portion of an output shaft support portion that stores one of the parts; and a bracket that stores the other side of the output shaft support portion and is disposed in the opening of the stator molded body, The output shaft support is an inner ring and a rolling element disposed on the outer periphery of the inner ring. An outer ring sandwiching the rolling element with the inner ring, and a seal plate that covers a side portion of the rolling element and is disposed in contact with the inner ring and the outer ring, and at least a part of the seal plate is electrically conductively slidable. This is a brushless motor having a portion.

  The sixth invention is the brushless motor according to the fourth or fifth invention, wherein the conductive sliding portion is composed of a plurality of conductive thin wires provided on at least a part of the seal plate. .

Moreover, 7th invention is the brushless motor of 6th invention,
A brushless motor having a configuration in which one end of a conductive thin wire is connected to a seal plate and the other end of the conductive thin wire is in contact with an inner ring or an outer ring.

  Further, an eighth aspect of the invention is the brushless motor of the sixth aspect, wherein one end of the conductive fine wire is connected to the seal plate, and the other end of the conductive fine wire is in contact with the inner ring and the outer ring. It is a brushless motor.

  A ninth invention is a brushless motor according to any of the second to eighth inventions, wherein the stator iron core and the bracket are electrically connected.

  The tenth invention is the brushless motor according to any of the second to eighth inventions, wherein the brushless motor has a dielectric layer between the outer peripheral surface of the rotor and the output shaft.

An eleventh aspect of the present invention is an output shaft support portion of a brushless motor,
An output shaft support portion for supporting the output shaft of the brushless motor includes an inner ring, a rolling element disposed on an outer peripheral portion of the inner ring, an outer ring that sandwiches the rolling element with the inner ring, and a side portion of the rolling element. And a seal plate disposed in contact with the inner ring and the outer ring, and an output shaft support portion of a brushless motor having a conductive sliding portion in at least a part of the seal plate.

  According to a twelfth aspect of the present invention, in the output shaft support portion of the motor, the output shaft support portion for supporting the output shaft of the motor includes an inner ring, a rolling element disposed on an outer peripheral portion of the inner ring, and the rolling element. An electric motor comprising: an outer ring sandwiched between the inner ring; a seal plate that covers a side portion of the rolling element and is disposed in contact with the inner ring and the outer ring; and a conductive sliding portion at least at a part of the seal plate. This is the output shaft support.

  A thirteenth invention is a brushless motor, wherein a stator winding body in which a winding is wound around a stator iron core insulated with resin, the stator winding body is molded with an insulating resin, and A stator molded body in which a part of the stator core is exposed, a rotor disposed to face a teeth portion of the stator, an output shaft that is axially attached to a shaft through hole of the rotor, and A pair of output shaft support portions for supporting the output shaft with a rotor interposed therebetween, and one of the output shaft support portions provided at the inner bottom of the exposed portion of the stator of the stator molded body are accommodated. A brushless motor comprising a storage portion of the output shaft support portion and a bracket that stores the other side of the output shaft support portion and is disposed in the opening of the stator molded body, wherein the output shaft support portion is An inner ring, a rolling element disposed on the outer periphery of the inner ring, and the rolling element An outer ring sandwiched between the inner ring and a seal plate that covers a side portion of the rolling element and is disposed in contact with the inner ring and the outer ring, and when the brushless motor is energized and driven, the inner ring and the This is a brushless motor in which a potential difference is generated between the outer ring and a brushless motor having a conductive sliding portion for short-circuiting the potential difference in at least a part of the seal plate.

  According to a fourteenth aspect of the present invention, there is provided a brushless motor having a control circuit unit, a stator winding body in which a winding is wound around a stator iron core insulated by a resin, and the stator winding body that is an insulating resin. The stator molded body molded with the above and a part of the stator iron core is exposed, the rotor disposed opposite to the teeth portion of the stator, and the shaft through-hole of the rotor. An output shaft, a pair of output shaft support portions for supporting the output shaft with the rotor interposed therebetween, and an output shaft support provided at an inner bottom portion of the exposed portion of the stator of the stator molded body. A brushless motor comprising: a storage portion of an output shaft support portion that stores one of the parts; and a bracket that stores the other side of the output shaft support portion and is disposed in the opening of the stator molded body, The output shaft support part is arranged on the inner ring and the outer periphery of this inner ring. And an outer ring that sandwiches the rolling element with the inner ring, and a seal plate that covers a side portion of the rolling element and is disposed in contact with the inner ring and the outer ring, and the brushless motor is energized and driven. In some cases, the brushless motor generates a potential difference between the inner ring and the outer ring, and the brushless motor has a conductive sliding portion that short-circuits the potential difference in at least a part of the seal plate.

  A fifteenth aspect of the present invention is the brushless motor according to any one of the second to tenth, thirteenth and fourteenth aspects of the present invention, wherein the stator core and the bracket are electrically connected.

  According to a sixteenth aspect of the present invention, in the brushless motors of the second to tenth, thirteenth and fourteenth aspects, the brushless motor is configured to be driven by a PWM inverter drive system.

  A seventeenth aspect of the invention is an electric device equipped with the brushless motor of the second to tenth, thirteenth, and fourteenth aspects.

  With the above structure, since the output shaft and the bracket in FIG. 4 have the same potential, the voltage applied to the output shaft support portion can be greatly reduced, and the occurrence of electrolytic corrosion can be suppressed.

  As described above, according to the present invention, since the output shaft and the bracket are at the same potential, the voltage applied to the output shaft support portion can be greatly reduced, and the occurrence of electrolytic corrosion can be suppressed. In other words, by electrically short-circuiting the inner ring and outer ring of the output shaft support part with the seal plate and the conductive sliding part, the potential between the output shaft and the bracket becomes the same, so that the rolling element of the output shaft support part Application of a potential that causes electrolytic corrosion can be reduced as compared with the conventional case.

  In addition, in the configuration in which the stator and the bracket are electrically short-circuited, or in the configuration of the brushless motor having a dielectric layer between the outer peripheral surface of the rotor and the output shaft, the space between the inner ring and the outer ring of the output shaft support portion Since the potential difference is reduced as compared with the prior art, wear and deterioration due to the potential difference of the sliding surface of the conductive sliding portion of the output shaft support portion are reduced, so that a more preferable effect can be obtained.

  Further, it is possible to provide a relatively simple and inexpensive measure without taking measures such as using an output shaft support portion of a ceramic ball, and it is possible to provide a brushless motor with a low-cost electric corrosion countermeasure. Thus, the industrial quality improvement effect is great.

(A) Structural sectional view of the brushless motor in Embodiment 1 of the present invention, (b) Structural sectional view of the output shaft support portion of the present invention Structure cross-sectional enlarged view of the periphery of the iron core connection terminal and bracket connection terminal shown in FIG. Cross-sectional view of the structure of a conventional brushless motor Model diagram of approximate distribution of stray capacitance of brushless motor Iron core connection terminal side view in Embodiment 2 of the present invention Side view of bracket connection terminal in embodiment 2 of the present invention Side view of stator before molding in Embodiment 3 of the present invention (enlarged view before stator core and core connection terminal welding) Side view of stator before molding in Embodiment 3 of the present invention (enlarged view after welding of stator core and core connection terminal) Enlarged view of the structural cross-sectional view before insertion of the bracket connection terminal in Embodiment 4 of the present invention The enlarged view of the structure sectional view before bracket insertion in Embodiment 4 of the present invention Front view of completion of stator before insertion of bracket connection terminal shown in FIG. 9 in Embodiment 5 of the present invention (enlarged view of iron core connection terminal portion) Front view of completed stator before bracket insertion shown in FIG. 10 according to Embodiment 5 of the present invention (enlarged view of bracket connection terminal insertion portion) Cross-sectional view of the structure of the brushless motor according to the sixth embodiment of the present invention Structural cross-sectional enlarged view of the periphery of the iron core connection terminal and bracket connection terminal shown in FIG. Structural diagram of electrical apparatus (air conditioner indoor unit) according to Embodiment 7 of the present invention Structural diagram of electrical apparatus (air conditioner outdoor unit) according to Embodiment 8 of the present invention Structure diagram of electrical apparatus (hot water heater) in Embodiment 9 of the present invention Structure diagram of electrical apparatus (air purifier) in Embodiment 10 of the present invention

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

(Embodiment 1)
FIG. 1 is a structural cross-sectional view of the motor according to Embodiment 1 of the present invention, and FIG. 2 is an enlarged structural cross-sectional view of the periphery of the iron core connection terminal and bracket connection terminal shown in FIG.

  A motor 80 shown in FIG. 1A is an air conditioner indoor unit fan motor (hereinafter referred to as an indoor unit motor). In FIG. 1, a motor 80 of the present embodiment includes a stator 70 formed by integrally molding a stator core 11 and a stator winding 12 wound around the stator core 11 with an insulating resin 13. The rotor 14 having the shaft 16, the first output shaft support portion 151 and the second output shaft support portion 152 for supporting the shaft 16, and the stator 70 are coupled to the first output shaft. A bracket 17 that holds at least one of the support portion 151 and the second output shaft support portion 152, an iron core conduction terminal 19 that short-circuits the stator core 11 and the bracket 17, and a bracket conduction terminal 20 are included.

  Further, the configuration of the motor 80 will be described in detail with reference to FIGS. 1 and 2. An insulator 21 is inserted into the stator core 11, and then a stator winding 12 is wound. Further, the core connection terminal 19 is fixed to the insulator 21 and then contacted or welded to the outer peripheral portion of the stator core 11.

  The contact or welding between the stator iron core 11 and the iron core connection terminal 19 has no problem even before the stator winding is applied. Through this process, the stator iron core 11 and the iron core connection terminal 19 can be electrically connected to each other, and the stator 70 is formed by molding with the insulating resin 13 to form the stator 70. The fitting portion with the connection terminal 20 is exposed.

  Furthermore, the groove | channel which can support the bracket connection terminal 20 is provided in at least 1 place of the stator 70, the bracket connection terminal 20 is inserted in the positioned iron core connection terminal 19, and it fixes by soldering or welding, and a stator core is obtained. 11 and the bracket connection terminal 20 can be conducted.

  Thereafter, a printed wiring board 18 on which a drive circuit for driving the motor 80 is mounted is added to form a finished mold, and the bracket 17 is finally press-fitted and fixed to the stator 70. The bracket connection terminal 20 protrudes from the end surface of the finished mold product, and is structured to be fixed to the bracket 17 by deforming the bracket connection terminal 20 at the same time as the bracket 17 is press-fitted. As a result, the stator core 11 has a structure in which the bracket 17 is short-circuited through the core connection terminal 19 and the bracket connection terminal 20.

  Note that a thermoplastic resin (PET, PBT or the like) is used for the resin member 21, and an unsaturated polyester resin that is a thermosetting resin is used for the insulating resin 13.

  On the other hand, a shaft 16 is press-fitted and fixed to the rotor 14. Further, two output shaft support portions that rotatably support the shaft 16, that is, a first output shaft support portion 151 and a second output shaft support portion 152 are attached to the shaft 16.

  A finished mold in which the printed wiring board 18 is added to the stator 70, that is, a rotor in which the first output shaft support portion 151 and the second output shaft support portion 152 are held on the shaft 16 with respect to the stator 70. The motor 80 is configured by incorporating 14 through the air gap. The first output shaft support portion 151 is held by the housing 30 formed on the stator 70, and the second output shaft support portion 152 is held by the bracket 17.

  FIG. 1B shows the configuration of the output shaft support 151. The inner ring 151a, the rolling element 151b disposed on the outer periphery of the inner ring 151a, the outer ring 151c sandwiching the rolling element 151b with the inner ring 151a, and the inner ring 151a and the outer ring 151b are covered with the side portions of the rolling element 151b. The sealing plate 151d is disposed, and the conductive sliding portion 151e is provided on at least a part of the sealing plate 151d. The conductive sliding portion is composed of a plurality of conductive thin wires 151e provided on at least a part of the seal plate 151d. One end of the conductive thin wire rod is connected to the seal plate 151d, and the other end of the conductive thin wire rod 151e is in contact with the inner ring 151a or the outer ring 151c.

  In the configuration of FIG. 1B, the conductive thin wire 151e is in contact with the inner ring 151a and the outer ring 151c, but may be in contact with the inner ring 151a or the outer ring 151c. Further, the conductive thin wire 151e may be in contact with either the inner ring 151a or the outer ring 151c in consideration of the potential relationship between the inner ring 151a and the outer ring 151c. The seal plate 151d has a substantially annular shape, and an L-shaped bent portion is provided at an end portion of the inner peripheral portion to form a surface facing the inner ring 151a, and the conductive thin wire material 151e is implanted on the facing surface. Has been. Also, an L-shaped bent portion may be provided at the outer peripheral side end of the seal plate 151d to form a surface facing the outer ring 151c, and the conductive thin wire material 151e may be planted on this facing surface. The flocked portion of the conductive thin wire 151e may be the entire inner peripheral end portion / outer peripheral end portion, or may be partially planted. Since innumerable sliding locations are formed on the contact surface between the tip of the conductive thin wire 151e and the inner ring 151a and the outer ring 151c, a stable electrical connection state is formed.

  The tip portion of the conductive thin wire 151e is an equivalent needle electrode, and the surface of the inner ring 151a or the outer ring 151c on which the conductive thin wire 151e is in contact is an equivalent substantially flat electrode. When any of the potential relationships with the negative potential side or the positive potential side is specified, there is a difference in the life time, the degree of wear, the degree of deterioration, etc. of the conductive sliding part due to this potential relationship. Is a configuration in which a better configuration can be selected.

  The connection between the seal plate 151d and the conductive thin wire 151e is performed with a conductive adhesive or the like. For example, a conductive adhesive or the like is applied to a portion of the seal plate 151d where the conductive thin wire 151e is desired to be implanted, and the seal plate 151d and the conductive thin wire 151e are connected through a process such as electrostatic flocking. .

  Further, in order to improve the slidability and conductivity between the conductive thin wire and the inner ring 151a or / and the outer ring 151c, conductive grease or the like is provided in a portion between the conductive thin wire and the inner ring 151a or / and the outer ring 151c. It may be applied.

  As the conductive thin wire 151e, conductive fibers, conductive fibers, semiconductive fibers, metal fibers, organic compound-based conductive fibers, polyester conductive fibers, iron-based fibers, or the like are appropriately used.

  With this configuration, the stator core 11 and the bracket 17 are short-circuited through the iron core connection terminal 19 and the bracket connection terminal 20 to have the same potential, so that the voltage applied to the two output shaft support portions 151 and 152 is greatly increased. Can be reduced. Further, by electrically short-circuiting the inner ring and the outer ring of the output shaft support part by the seal plate and the conductive sliding part, the output shaft and the bracket have the same potential, and the output shaft support part is rotated. The application of a potential that causes electrolytic corrosion on the moving body can be reduced as compared with the conventional case, and as a result, generation of electrolytic corrosion can be suppressed. Therefore, it is not necessary to take measures such as using the ceramic ball output shaft support, and it is possible to provide a motor that is relatively simple and inexpensive and has anti-corrosion measures. In addition, since the potential difference between the inner ring and the outer ring of the output shaft support portion is reduced as compared with the prior art, wear and deterioration due to the potential difference of the sliding surface of the conductive sliding portion of the output shaft support portion are also small. Therefore, a more preferable effect can be obtained.

  In addition, in the case where a brushless motor configuration having a dielectric layer (not shown) is added between the outer peripheral surface of the rotor and the output shaft, the potential difference between the inner ring and the outer ring of the output shaft support portion is larger than before. Since it is reduced, wear and deterioration due to the potential difference of the sliding surface of the conductive sliding portion of the output shaft support portion are also reduced, so that a more preferable effect can be obtained.

  Needless to say, when the shaft voltage and the shaft current are relatively small values, the configuration of the present invention can sufficiently exhibit the effects of the present invention even if the core connection terminal 19 is omitted. Similarly, it goes without saying that the effect of the present invention can be sufficiently exerted even in a configuration excluding the dielectric layer disposed between the outer peripheral surface of the rotor and the output shaft.

  In the present embodiment, as shown in FIG. 2, the effect is great when the bracket 17 disposed on the printed wiring board 18 side and the stator core 11 are short-circuited.

(Embodiment 2)
FIG. 5 is a side view of the iron core connection terminal 19 according to the second embodiment of the present invention, and FIG. 6 is a side view of the bracket connection terminal 20. In FIG. 5, the iron core connection terminal 19 has a shape obtained by bending a distance of the dimension K. This is an example to ensure contact with the stator core 11 according to FIG. In FIG. 6, the bracket connection terminal 20 has a structure in which an iron core connection part insertion hole 23 is provided in consideration of a fixed connection with the iron core connection terminal 19.

  In addition, these parts are preferably made of a spring-made material (for example, phosphor bronze), welded, or soldered brass.

  By providing these two connecting parts, the stator core 11 and the bracket 17 can be reliably positioned and short-circuited.

  The configuration of the output shaft support portion is the same as that of the first embodiment.

  Further, when the shaft voltage and shaft current are relatively small values, the effect of the present invention can be sufficiently exerted even in the configuration in which the core connection terminal and the dielectric layer of the rotor are omitted as in the first embodiment. Needless to say, you can.

(Embodiment 3)
7 and 8 are side views of the stator before molding in the third embodiment of the present invention (enlarged view before stator core and core connection terminal welding) and the side surfaces of the stator before molding. It is a figure (enlarged view after stator iron core and iron core connection terminal welding).

By pressing and fixing the iron core connection terminal 19 shown in FIG. 5 to the insulator 22, the iron core connection terminal 19 can be positioned and contacted with the stator iron core 11. Further, as shown in FIG. 8, the welded portion 24 is provided by spot welding or the like between the stator core 11 and the core connection terminal 19.
Thus, a structure in which the stator core 11 and the core connection terminal 19 are reliably short-circuited is possible.

  The configuration of the output shaft support portion is the same as that of the first embodiment.

  Further, when the shaft voltage and shaft current are relatively small values, the effect of the present invention can be sufficiently exerted even in the configuration in which the core connection terminal and the dielectric layer of the rotor are omitted as in the first embodiment. Needless to say, you can.

(Embodiment 4)
9 and 10 are an enlarged view of a structural sectional view before insertion of the bracket connection terminal 20 and an enlarged view of the structural sectional view before insertion of the bracket 17 in Embodiment 4 of the present invention.

  In FIG. 9, at least one notch is provided in the outer peripheral portion of the finished mold product, and the bracket connection terminal 20 can be accommodated there. Further, after the bracket connection terminal 20 is inserted into a designated place and fixed with the solder 24, it is press-fitted and fixed on both the inner diameter side and the outer diameter side of the bracket 17. When the bracket 17 is press-fitted, the bracket connection terminal 20 is configured such that the distance of the dimension L protrudes from the end face of the finished mold product, and the distance of the dimension L is deformed when the bracket 17 is press-fitted to make sure that the bracket contact terminal 20 contacts It is said. Finally, the stator core 11 can be structured to reliably short-circuit the bracket 17 via two types of terminals (iron core connection terminal 19 and bracket connection terminal 20).

Further, in the configuration of FIG. 10, a structure in which the dimension N of the bracket connection terminal 20 is longer than the dimension M of the bracket 17 allows the bracket connection terminal 20 to be seen even after the bracket 17 is inserted (after the motor is assembled). Therefore, it is possible to confirm conduction (short circuit) between the bracket 17 and the bracket connection terminal 17 (finally the stator core 11).
The continuity can be confirmed by a continuity check device such as a tester, a multimeter, or a ground continuity test device.

  The configuration of the output shaft support portion is the same as that of the first embodiment.

  Further, when the shaft voltage and shaft current are relatively small values, the effect of the present invention can be sufficiently exerted even in the configuration in which the core connection terminal and the dielectric layer of the rotor are omitted as in the first embodiment. Needless to say, you can.

(Embodiment 5)
FIG. 11 is a front view of the completed stator before insertion of the bracket connection terminal 20 shown in FIG. 9 in the fifth embodiment of the present invention (enlarged view of the iron core connection terminal portion 19), and FIG. 12 is before insertion of the bracket shown in FIG. It is a front view (enlarged view of the bracket connection terminal 20 insertion part) of a stator completion. In FIG. 11, a portion of the insulating resin 13 is provided with a notch, and the bracket connection terminal 20 is inserted at that location, and positioning with the iron core connection terminal portion 19 is performed.

  In FIG. 12, when the bracket connection terminal 20 is fixed by soldering or welding, and when the bracket 17 is further press-fitted, the side surface of the bracket connection terminal 20 and the bracket 17 are prevented from applying stress to the solder fixing or welding fixing part. Both sides (inside and outside of the bracket: hatched area) are not in contact with each other.

  The configuration of the output shaft support portion is the same as that of the first embodiment.

  Further, when the shaft voltage and shaft current are relatively small values, the effect of the present invention can be sufficiently exerted even in the configuration in which the core connection terminal and the dielectric layer of the rotor are omitted as in the first embodiment. Needless to say, you can.

(Embodiment 6)
13 is a structural cross-sectional view of the brushless motor according to the sixth embodiment of the present invention, and FIG. 14 is an enlarged structural cross-sectional view of the periphery of the iron core connection terminal 19 and the bracket connection terminal 20 shown in FIG. 1 shows an embodiment of a fan motor used outdoors (hereinafter referred to as “outdoor motor”). The difference from the indoor motor is that the iron core connection terminal 19 and the bracket connection terminal 20 are located below (lead wire side) in the figure, and the output shaft support portion on the opposite side of the bracket 17 is the bracket A25. It is held.

  The outdoor motor may be exposed to wind and rain depending on the usage environment, and there is a concern that water may enter the motor from the gap around the conductive pin. As one of the countermeasures against this, by positioning the core connection terminal 19 and the bracket connection terminal 20 so that they are on the lower side when the motor is installed, it is not directly exposed to wind and rain, so that water can enter the motor. Can be prevented.

  It is well known that there are many cases where electric corrosion occurs at the output shaft support portion closer to the printed circuit board 18, but for the reason described above, the bracket 17 is not the bracket A25 but the bracket connection terminal 20. Since the effect of reducing the voltage applied to the output shaft support is greater when short-circuited with the stator core 11 via the core connection terminal 19, this is also implemented in the outdoor motor.

  The configuration of the output shaft support portion is the same as that of the first embodiment.

  Further, when the shaft voltage and shaft current are relatively small values, the effect of the present invention can be sufficiently exerted even in the configuration in which the core connection terminal and the dielectric layer of the rotor are omitted as in the first embodiment. Needless to say, you can.

(Embodiment 7)
As an example of the electric apparatus according to the present invention, first, the configuration of an air conditioner indoor unit will be described in detail as a seventh embodiment.

  In FIG. 15, a brushless motor 201 is mounted in the casing 211 of the air conditioner indoor unit 210. A cross flow fan 212 is attached to the rotating shaft of the brushless motor 201. The brushless motor 201 is driven by a motor driving device 213. The brushless motor 201 is rotated by energization from the motor driving device 213, and the cross flow fan 212 is rotated accordingly. By the rotation of the cross flow fan 212, air conditioned by an indoor unit heat exchanger (not shown) is blown into the room. Here, as the brushless motor 201, for example, the one of the first to sixth embodiments can be applied.

  The electric device of the present invention includes a brushless motor and a casing on which the brushless motor is mounted, and employs the motor of the present invention having the above-described configuration as a brushless motor.

  The configuration of the output shaft support portion is the same as that of the first embodiment.

  Further, when the shaft voltage and shaft current are relatively small values, the effect of the present invention can be sufficiently exerted even in the configuration in which the core connection terminal and the dielectric layer of the rotor are omitted as in the first embodiment. Needless to say, you can.

(Embodiment 8)
Next, as an example of the electrical apparatus according to the present invention, the configuration of an air conditioner outdoor unit will be described in detail as an eighth embodiment.

  In FIG. 16, the air conditioner outdoor unit 301 has a brushless motor 308 mounted inside a housing 311. The brushless motor 308 has a fan 312 attached to a rotating shaft and functions as a fan motor for blowing air.

  The air conditioner outdoor unit 301 is partitioned into a compressor chamber 306 and a heat exchanger chamber 309 by a partition plate 304 erected on the bottom plate 302 of the housing 311. A compressor 305 is disposed in the compressor chamber 306. A heat exchanger 307 and the blower fan motor are disposed in the heat exchanger chamber 309. An electrical component box 310 is disposed above the partition plate 304.

  The blower fan 312 rotates with the rotation of the brushless motor 308 driven by the motor driving device 303 housed in the electrical component box 310, and the heat fan chamber 309 passes through the heat exchanger 307. To blow. Here, as the brushless motor 308, for example, the one of the first to sixth embodiments can be applied.

  The electric device of the present invention includes a brushless motor and a housing on which the brushless motor is mounted, and employs the brushless motor of the present invention having the above-described configuration as a brushless motor.

  The configuration of the output shaft support portion is the same as that of the first embodiment.

  Further, when the shaft voltage and shaft current are relatively small values, the effect of the present invention can be sufficiently exerted even in the configuration in which the core connection terminal and the dielectric layer of the rotor are omitted as in the first embodiment. Needless to say, you can.

(Embodiment 9)
Next, as an example of the electric apparatus according to the present invention, the configuration of the hot water heater will be described in detail as a ninth embodiment.

  In FIG. 17, a brushless motor 333 is mounted in a housing 331 of the water heater 330. A fan 332 is attached to the rotation shaft of the brushless motor 333.

  The brushless motor 333 is driven by a motor driving device 334. The brushless motor 333 is rotated by energization from the motor driving device 334, and the fan 332 is rotated accordingly. The rotation of the fan 332 blows air necessary for combustion to a fuel vaporization chamber (not shown). Here, as the brushless motor 333, for example, those of the first to sixth embodiments can be applied.

  The electric device of the present invention includes a brushless motor and a casing on which the brushless motor is mounted, and employs the motor of the present invention having the above-described configuration as a brushless motor.

  The configuration of the output shaft support portion is the same as that of the first embodiment.

  Further, when the shaft voltage and shaft current are relatively small values, the effect of the present invention can be sufficiently exerted even in the configuration in which the core connection terminal and the dielectric layer of the rotor are omitted as in the first embodiment. Needless to say, you can.

(Embodiment 10)
Next, as an example of the electrical apparatus according to the present invention, the configuration of the air cleaner will be described in detail as a tenth embodiment.

  In FIG. 18, a brushless motor 343 is mounted in the housing 341 of the air purifier 340. An air circulation fan 342 is attached to the rotation shaft of the brushless motor 343. The brushless motor 343 is driven by a motor driving device 344. The brushless motor 343 is rotated by energization from the motor driving device 344, and the fan 342 is rotated accordingly. Air is circulated by the rotation of the fan 342.

  Here, as the brushless motor 343, for example, those of the first to sixth embodiments can be applied.

  The configuration of the output shaft support portion is the same as that of the first embodiment.

  Further, when the shaft voltage and shaft current are relatively small values, the effect of the present invention can be sufficiently exerted even in the configuration in which the core connection terminal and the dielectric layer of the rotor are omitted as in the first embodiment. Needless to say, you can.

The electric device of the present invention includes a brushless motor and a casing on which the brushless motor is mounted, and employs the motor of the present invention having the above-described configuration as a brushless motor.
In the above description, fan motors mounted on air conditioner outdoor units, air conditioner indoor units, water heaters, air purifiers, etc. have been taken up as embodiments of the electrical equipment according to the present invention. Needless to say, the present invention can also be applied to brushless motors mounted on various information devices and brushless motors used in industrial devices.

  The brushless motor according to the present invention has a structure in which the stator iron core and the bracket are short-circuited through the iron core connection terminal and the bracket connection terminal in the stator of the brushless motor molded with an insulating resin. An object of the present invention is to reduce the voltage, and to prevent electric corrosion and wavy wear of the output shaft support.

  This is mainly a low-priced device that requires a long life and is effective for a brushless motor of an electric motor such as a fan motor mounted in an air conditioner indoor unit, an air conditioner outdoor unit, a water heater, an air purifier or the like.

DESCRIPTION OF SYMBOLS 11 Stator iron core 12 Stator winding 13 Insulation resin 14 Rotor 15, 151, 152 Output shaft support part 16 Shaft 17 Bracket 18 Printed circuit board 19 Iron core connection terminal 20 Bracket connection terminal 21 Insulator 22 Solder 23 Iron core connection component insertion hole 24 Welded part 25 Bracket A
30 Housing 70 Stator 80 Motor 151a Inner ring 151b Rolling element 151c Outer ring 151d Seal plate 151e Conductive thin wire (conductive sliding layer)
201 Brushless motor 210 Air conditioner indoor unit 211 Housing 212 Cross flow fan 213 Motor drive device 301 Air conditioner outdoor unit 302 Bottom plate 303 Motor drive device 304 Partition plate 305 Compressor 306 Compressor chamber 307 Heat exchanger 308 Brushless motor 309 Heat exchanger chamber 310 Electrical component box 311 Housing 312 Fan 330 Water heater 331 Housing 332 Fan 333 Brushless motor 334 Motor driving device 340 Air purifier 341 Housing 342 Fan 343 Brushless motor 344 Motor driving device

Claims (17)

In the electric motor, an output shaft support portion that supports the output shaft of the electric motor includes an inner ring, a rolling element disposed on an outer peripheral portion of the inner ring, an outer ring that sandwiches the rolling element with the inner ring, and the rolling element. An electric motor comprising a sealing plate that covers a side portion and is disposed in contact with the inner ring and the outer ring, and having a conductive sliding portion in at least a part of the sealing plate. In the brushless motor, the output shaft support portion that supports the output shaft of the brushless motor includes an inner ring, a rolling element disposed on an outer peripheral portion of the inner ring, an outer ring that sandwiches the rolling element with the inner ring, and the rolling ring. A brushless motor comprising a seal plate that covers a side portion of a moving body and is disposed in contact with the inner ring and the outer ring, and having a conductive sliding portion in at least a part of the seal plate. In a brushless motor having a control circuit portion, an output shaft support portion for supporting the output shaft of the brushless motor includes an inner ring, a rolling element disposed on an outer peripheral portion of the inner ring, and the rolling element sandwiched between the inner ring and the inner ring. A brushless motor, comprising: an outer ring that covers the side of the rolling element; and a seal plate that is disposed in contact with the inner ring and the outer ring, and has a conductive sliding portion at least in part of the seal plate. In a brushless motor, a stator winding body in which a winding is wound around a stator iron core insulated with resin, and the stator winding body is molded with an insulating resin and a part of the stator core is exposed. A stator molded body, a rotor disposed opposite to the teeth portion of the stator, an output shaft attached to a shaft through-hole of the rotor, and the rotor disposed therebetween. A pair of output shaft support portions that support the output shaft; and a storage portion of an output shaft support portion that is provided on an inner bottom portion of the exposed portion of the stator of the stator molded body and stores one of the output shaft support portions; A brushless motor that accommodates the other of the output shaft support portions and includes a bracket disposed at an opening of the stator molded body, wherein the output shaft support portion includes an inner ring and an outer peripheral portion of the inner ring. A rolling element disposed on the outer ring, and an outer ring sandwiching the rolling element with the inner ring, Wherein a seal plate disposed in contact with the inner ring and the outer ring covering the sides of the rolling element, the brushless motor having a conductive sliding portion in at least a portion of the seal plate. In a brushless motor having a control circuit unit, a stator winding body in which a winding is wound around a stator iron core insulated with resin, the stator winding body is molded with an insulating resin, and the stator A stator molded body in which a part of the iron core is exposed, a rotor disposed to face the teeth portion of the stator, an output shaft axially attached to a shaft through hole of the rotor, and the rotor And a pair of output shaft support portions for supporting the output shaft, and an output shaft for housing one of the output shaft support portions provided at an inner bottom portion of the exposed portion of the stator of the stator molded body A brushless motor comprising: a housing portion for a bearing portion; and a bracket that accommodates the other of the output shaft bearing portions and is disposed at an opening of the stator molded body, wherein the output shaft bearing portion is an inner ring. A rolling element disposed on the outer periphery of the inner ring, and the rolling element An outer ring which rings and holding, and a sealing plate disposed in contact with the inner ring and the outer ring covering the side of the rolling element, a brushless motor having a conductive sliding portion in at least a portion of the seal plate. 6. The brushless motor according to claim 4 or 5, wherein the conductive sliding portion is made of a plurality of conductive thin wires provided on at least a part of the seal plate. 7. The brushless motor according to claim 6, wherein one end of the conductive thin wire is connected to a seal plate, and the other end of the conductive thin wire is in contact with the inner ring or the outer ring. 7. The brushless motor according to claim 6, wherein one end of the conductive thin wire is connected to a seal plate, and the other end of the conductive thin wire is in contact with the inner ring and the outer ring. 9. The brushless motor according to claim 2, wherein the stator core and the bracket are electrically connected to each other. 9. The brushless motor according to claim 2, further comprising a dielectric layer between the outer peripheral surface of the rotor and the output shaft. In the output shaft support portion of the brushless motor, the output shaft support portion that supports the output shaft of the brushless motor includes an inner ring, a rolling element disposed on the outer periphery of the inner ring, and the rolling element sandwiched between the inner ring and the inner ring. An output shaft support portion of a brushless motor, comprising: an outer ring; a seal plate that covers a side portion of the rolling element and is disposed in contact with the inner ring and the outer ring; and at least a portion of the seal plate includes a conductive sliding portion. In the output shaft support portion of the electric motor, the output shaft support portion for supporting the output shaft of the motor includes an inner ring, a rolling element disposed on the outer peripheral portion of the inner ring, and an outer ring sandwiching the rolling element with the inner ring. ,
A seal plate that covers a side portion of the rolling element and is disposed in contact with the inner ring and the outer ring,
An output shaft support portion of an electric motor having a conductive sliding portion in at least a part of the seal plate. In a brushless motor, a stator winding body in which a winding is wound around a stator iron core insulated with resin, and the stator winding body is molded with an insulating resin and a part of the stator core is exposed. A stator molded body, a rotor disposed opposite to the teeth portion of the stator, an output shaft attached to a shaft through-hole of the rotor, and the rotor disposed therebetween. A pair of output shaft support portions that support the output shaft; and a storage portion of an output shaft support portion that is provided on an inner bottom portion of the exposed portion of the stator of the stator molded body and stores one of the output shaft support portions; A brushless motor that accommodates the other of the output shaft support portions and includes a bracket disposed at an opening of the stator molded body, wherein the output shaft support portion includes an inner ring and an outer peripheral portion of the inner ring. A rolling element disposed on the outer ring, and an outer ring sandwiching the rolling element with the inner ring, And a sealing plate disposed in contact with the inner ring and the outer ring covering the side of the rolling element, energized the brushless motor, when was driven,
A brushless motor in which a potential difference is generated between the inner ring and the outer ring, and a conductive sliding portion that short-circuits the potential difference is provided in at least a part of the seal plate. In a brushless motor having a control circuit unit, a stator winding body in which a winding is wound around a stator iron core insulated with resin, the stator winding body is molded with an insulating resin, and the stator A stator molded body in which a part of the iron core is exposed, a rotor disposed to face the teeth portion of the stator, an output shaft axially attached to a shaft through hole of the rotor, and the rotor And a pair of output shaft support portions for supporting the output shaft, and an output shaft for housing one of the output shaft support portions provided at an inner bottom portion of the exposed portion of the stator of the stator molded body A brushless motor comprising: a housing portion for a bearing portion; and a bracket that accommodates the other of the output shaft bearing portions and is disposed at an opening of the stator molded body, wherein the output shaft bearing portion is an inner ring. A rolling element disposed on the outer periphery of the inner ring, and the rolling element An outer ring that is sandwiched between a ring and a seal plate that covers a side portion of the rolling element and is disposed in contact with the inner ring and the outer ring, and when the brushless motor is energized and driven, A brushless motor that generates a potential difference with an outer ring, and has a conductive sliding portion that short-circuits the potential difference in at least a part of the seal plate. The brushless motor according to any one of claims 2 to 10, 13, or 14, wherein the stator iron core and the bracket are electrically connected to each other. The brushless motor according to any one of claims 2 to 10, 13, or 14, wherein the brushless motor is configured to be driven by a PWM inverter drive system. An electrical device on which the brushless motor according to any one of claims 2 to 10, 13, or 14 is mounted.