CN2464008Y - Brushless dc motor derectly driving washing machine - Google Patents

Abstract

The utility model relates to a brushless direct-current motor for directly driving a washing machine, which is suitable for direct-driven fully automatic pulsator washing machines and drum washing machines. The number of magnetic poles of the rotor of the utility model is P=20, and the number of slots of the stator core is Z=21; uniform tooth groove structure is adopted, and the width of the groove is 3.5mm; two square wave Hall position sensors are used, and an engineering plastic sleeve is added between the rotor shell and the mechanical transmission shaft. The utility model has the advantages of small positioning torque, low noise, stable performance and extensive social and economic benefits.

Description

Directly drive the brushless DC motor of washing machine

The utility model relates to a kind of brushless DC motor of direct driving washing machine, and specifically a kind of external rotor three-phase brushless permanent magnet direct current motor that is exclusively used in washing machine is applicable to the full automatic impeller type washing machine and the drum type washing machine of direct driving.

Conventional washer generally adopts the drive motors of single-phase capacitance operation induction motor as washing machine.The operational efficiency of capacitance operation induction motor is very low, generally has only about 50%, and when making drive motors owing to the usability induction motor again, essential reduction gearing and the belt pulley of using, therefore, operational efficiency is just lower.So the someone uses the drive motors of brushless direct-current permanent magnet motor as washing machine instead.The operational efficiency of brushless direct-current permanent magnet motor is very high, more than 90%, after the electronic circuit speed regulating control, can remove reduction gearing and belt pulley, realizes directly driving, and has reduced noise greatly.And system effectiveness increases.But because the poor structure of the stator that prior art adopted size makes the processing technology of this motor become rather complicated, production cost has increased.Owing to adopt three hall position sensors, increased production cost again again, more be number of magnetic poles P=24 because teeth groove cooperates; Groove is counted Z=36, and the location torque number of times that this gear grooved cooperates is 72 times, and its amplitude can be very big, must adopt big sulculus to be remedied.Many (Z=36) are favourable for reducing location torque for the groove number, and location torque is the most important source of motor electromagnetic noise, and the many more production technologies of groove number are complicated more, and production cost will be high more.The iron loss of number of poles many (P=24) motor increases.

The purpose of this utility model is at the deficiency that prior art exists, and proposes a kind of simple in structurely, and the cost cost is low, the direct driving brushless DC motor that efficient is high.

The purpose of this utility model is achieved in that the utility model mainly is made up of stator, rotor, permanent magnet, transducer and plastic sheath that the punching of silicon steel sheet laminates, the main points that the present utility model is created are, the number of magnetic poles of rotor 1 is P=20, the groove of stator core 2 is counted Z=21, adopt even teeth groove structure, notch 3 width are 3.5 millimeters, and transducer adopts two Hall switch to distribute by 90 ° of electrical degrees in the space.Described Hall element is the Hall switch of switching mode, so, not high to the installation site required precision.Only need the magnetosensitive sense direction of hall position sensor is consistent with the rotor normal direction, be installed on the internal stator support 8, and and rotor magnetic steel in keep the air gap of 1-2mm between the circle, Hall element 10,11 is arranged on the same circumference, space angle is 1/2 pole span, i.e. 90 ° of electrical degrees.Hall element of the present utility model also can be by being installed on the stator support 9, and and the rotor magnetic steel cylindrical between keep the air gap of 1-2mm, Hall element 10,11 is arranged on the same circumference, space angle is 1/2 pole span, i.e. 90 ° of electrical degrees.The utility model concrete structure: rotor 1 is a bowl-type, stator 2 is the open circles annular, stator 2 and rotor 1 are coaxial, stator 2 is installed in 1 bowl of the rotor by axle system, permanent magnet 5 sticks on the inwall of rotor 1, between rotor 1 and the axle system plastic sheath 20 is arranged, and transducer 10 and 11 is installed on the support 8, support 8 is contained in stator 2 upper surfaces, and coil is in the groove of stator 2.The punching 14 of each layer silicon steel sheet is made up of three identical 120 ° of fan types of shape punching 15, there are two through holes 16 in the yoke portion of 120 ° of fan types punching, diameter is 3-5mm, angle is 60 ° between two through hole, be symmetrically distributed in the yoke portion of fan type punching, the punching of three fan types in one plane constitutes a circular ring type stator punching, so, the annulus stator punching has three pieces, in order to reduce the influence of piece, when every circular ring type stator punching is carried out chip, from circular ring type stator punching of lowermost layer to the stator core magnetic circuit, circular ring type stator punching of every increase, 60 ° of all clockwise or counter-clockwise wrong sheets.Because symmetry, happening frequently through above-mentioned wrong sheet still maintains 6 through holes 16 in the stator core that comes, passes 6 through holes in the stator core with upper and lower pressure ring 17,18 of stator core and thin iron staff again, and the stator core riveting is become an integral body.The utility model also can be positioned at two through holes of each fan type punching yoke portion two grooves 19 of yoke portion circle, the about 3-6m of groove width, the about 1-2mm of groove depth instead.60 ° of wrong sheets are carried out in this punching as stated above, utilize 6 grooves after pressure ring 17,18 compresses up and down with stator core again, stator core is welded into a complete stator core.In order further to simplify stator core processing, solve the stock utilization problem, the utility model also can or be positioned at two grooves 19 of yoke portion circle with two through holes 16 of above-mentioned each fan type punching yoke portion, be positioned at the blind hole 21 of two drawings of 120 ° of segmental punching yoke portion circles instead, the about 2-3mm of the diameter of blind hole, the degree of depth of blind hole is 1/2 punching thickness; Angle is 60 ° between two blind holes; Three segmental punchings in one plane constitute a circular ring type stator punching, so, the circular ring type stator punching has three pieces, in order to reduce the influence of piece to the stator core magnetic circuit, when every annular stator punching is carried out chip, from circular ring type stator punching of lowermost layer, whenever add repeatedly a circular ring type stator punching with regard to 60 ° of angles of clockwise or counterclockwise wrong sheet, because the symmetry that blind hole 21 distributes, through happen frequently every segmental punching of the stator core that comes of mistake sheet is self-align, again with in the stator core, following pressure ring 17,18 compress the back becomes a complete stator core by injection moulding with the stator core plastic compression.Increased an engineering plastics cover 20 between the utility model rotor case and the mechanical drive shaft, because engineering plastics are connected between rotor steel body and the mechanical drive shaft, its elastic characteristic has cushioned the transfer strength of harmonic wave moment greatly.Improved the free oscillation attribute of washing machine integral body, thereby the noise level of washing machine integral body is increased again.

The utility model is rational in infrastructure, stable performance, and location torque is little, and noise is low, and production cost descends, and motor is exerted oneself greatly, is with a wide range of applications.

Fig. 1 is the utility model principle assumption diagram.

Fig. 2 is the utility model stator principle assumption diagram.

Fig. 3 is the utility model magnet steel principle assumption diagram.

Fig. 4 is the utility model magnet steel principle assumption diagram.

Fig. 5 is the utility model fan type punching principle assumption diagram.

Fig. 6 is the round punching principle assumption diagram of the utility model.

Fig. 7 is the round punching principle assumption diagram of the utility model.

Fig. 8 is the round punching yoke of a utility model portion location blind hole schematic diagram.

Fig. 9 is the round punching yoke of a utility model portion location blind hole schematic diagram.

Figure 10 is the utility model stator scheme of installation.

Figure 11 is second kind of embodiment principle assumption diagram of the utility model.

Embodiment:

Utilize the utility model technology to realize a kind of external rotor three-phase brushless dc permanent magnet motor that is exclusively used in direct driving washing machine.The number of magnetic poles P of the rotor 1 of this dc permanent magnet motor is 20, and it is 21 that the groove of stator core 2 is counted Z, and the width of notch 3 is 3.5mm, and employed position transducer is the Hall switch of two square wave output forms; Two Hall switch are 90 ° of electrical degrees at space quadrature, and motor has adopted even teeth groove structure, and width of rebate is 3.5mm, and the lead that is fit to very much the different-diameter of all kinds of washing machines is walked and coiling in this sizes of notch.

Claims (6)

1. A brushless DC motor for directly driving a washing machine, comprising a stator, a rotor, a permanent magnet, and a sensor formed by laminating punched silicon steel sheets; Between the rotor shell and the mechanical transmission shaft, the number of magnetic poles P of the rotor [1] is 20, the number of slots Z of the stator core [2] is 21; the width of the notch [3] is 3.5 mm, and the position sensor used is two Hall switch of the square wave output type, the phase difference of the two Hall switches in space is 90° electrical angle, the size of the magnetic steel pole pitch [13] is 28-35mm, and the magnetic sensitivity direction of the Hall position sensor and the rotor The normal direction is consistent, installed on the inner stator bracket [8], and maintains an air gap of 1-2mm between the inner circle of the rotor magnetic steel, and the two Hall sensors [10], [11] are arranged on the same circle , the space angle is 1/2 pole pitch, that is, 90° electrical angle. 2. The motor according to claim 1, characterized in that: the magnetic sensitivity direction of the Hall position sensor is consistent with the normal direction of the rotor, installed on the stator bracket [9], and kept 1 between the outer circle of the rotor magnetic steel -2mm air gap. 3. The motor according to claim 1, characterized in that: when the permanent magnet is a bonded NdFeB magnet, the difference between the two radii is 3-4mm; when the permanent magnet is a ferrite magnet, the difference between the two radii The value is 6-8mm. The two sides [6] and [7] of the inner circle of the tile-shaped magnetic steel are chamfered by straight lines or arcs, and the lengths of the two straight lines or arcs corresponding to the chamfered parts are respectively 1/3 of the total arc length of the inner circle, the two straight lines or arcs corresponding to the chamfered part intersect with the inner circle respectively, the arc length or the radial depth of the chamfered corner is the difference between the radius R ₁ of the inner circle and the radius R ₂ of the outer circle 1/3 of. 4. The motor according to claim 1, characterized in that: the punching sheet [14] of the first silicon steel sheet is composed of three 120° fan-shaped punching sheets [15] with the same shape, and the yoke of the 120° fan-shaped punching sheet There are two through-holes [16] at the top, with a diameter of 3-5mm, and the angle between the two through-holes is 60°, which are symmetrically distributed on the yoke of the fan-shaped punches, and three fan-shaped punches form a ring-shaped stator on a plane Punching, when chipping each ring-shaped stator punch, start from the lowest layer of a ring-shaped stator punch, and each time a ring-shaped stator punch is added, the clockwise or counterclockwise angle is staggered by 60°, due to symmetry , there are still 6 through-holes [16] on the stator core after staggered stacking, and then use the upper and lower pressure rings [17], [18] and thin iron rods to pass through the 6 through-holes on the stator core. holes, riveting the stator core into a whole. 5. The motor according to claim 1, characterized in that: each silicon steel sheet punch [14] is composed of three 120° fan-shaped punches [15] with exactly the same shape, and the inside of the yoke of the 120° fan-shaped punch The circle has two grooves [19], the groove width is about 3-6mm, the groove depth is about 1-2mm, and the angle between the two grooves is 60°. Three fan-shaped punches form a ring-shaped stator punch on a plane. , when chipping each ring-shaped stator punch, starting from the lowest layer of a ring-shaped stator punch, every time a ring-shaped stator punch is added, the electrical angle is staggered clockwise or counterclockwise by 60°, due to symmetry , the stator core after staggered stacking still maintains 6 grooves [19], and then the upper and lower pressure rings [17] and [18] of the stator core are used to compress the stator core and use 6 grooves to weld the stator core into a complete Stator core. 6. The motor according to claim 1, characterized in that: each silicon steel sheet punch [14] is composed of three 120° fan-shaped punches [15] with exactly the same shape, and the inside of the yoke of the 120° fan-shaped punch There are two punched blind holes [21] in the circle, the diameter of the blind holes is about 2-3mm, the depth of the blind holes is about 1/2 of the thickness of the stator punch, and the angle between the two blind holes is 60°. The fan-shaped stampings form a ring-shaped stator punching sheet on a plane. Starting from the lowest layer of a ring-shaped stator punching sheet, every time a ring-shaped stator punching sheet is added, the electrical angle is staggered by 60° clockwise or counterclockwise. Due to blind The symmetry of the distribution of the holes [21], each fan-shaped punching sheet of the stator core after the staggered stacking is self-positioning, and then the upper and lower pressing rings [17] and [18] of the stator core are pressed, and the stator core is molded by injection molding. Welded into a complete stator core.

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