BR102016010297A2 - drive apparatus for a washing machine and washing machine - Google Patents

Abstract

A driving apparatus for a washing machine includes a single-phase outer brushless motor rotor and a driving wheel. the motor drives the driving wheel and includes a stator and a rotor. the stator includes a stator core and windings wound around the stator core. the rotor includes a yoke rotor, and a permanent magnet. an inner surface of the permanent magnet and an outer surface of a tooth tip are opposed to each other and defines an uneven gap in there for allowing the rotor to rotate relative to the stator. a radial width of the gap associated with each magnetic pole progressively increases from a center portion toward circumferential ends of the magnetic pole, and a radial width of the gap associated with each magnetic pole is symmetrical with respect to a center axis of the magnetic pole along the circumferential direction.

Description

"DRIVE FOR A WASHING MACHINE, AND, WASHING MACHINE" FIELD OF THE INVENTION

This invention relates to drive apparatus for a washing machine, and in particular to a drive apparatus for driving a drum of a washing machine.

BACKGROUND OF THE INVENTION

A drive apparatus for driving washer drums generally includes a motor. Traditionally, permanent magnet synchronous motors are widely used in washing machines. The permanent magnet synchronous motor usually includes a rotor and a stator surrounding the rotor. The stator comprises a stator core with a plurality of teeth, and a winding composed of a plurality of coils. Each coil is wound around multiple teeth and adjacent coils have overlapping ends. Therefore, wound coils then have high bobbin ends that waste material. This type of permanent magnet synchronous motor tends to be bulky and heavy.

SUMMARY OF THE INVENTION

Thus, there is a desire for a drive apparatus for a washer with reduced size and weight.

In one aspect, there is provided a drive apparatus for a washing machine, which includes a single-phase external rotor brushless motor and a motor-driven transmission mechanism. The single-stage external rotor brushless motor is configured to drive a washer drum to rotate through the drive mechanism. The single-phase external rotor brushless motor includes a stator and a rotor. The stator includes a stator core and windings wound around the stator core. The stator core includes a breech and a plurality of teeth extending radially outwardly from the breech. Each of the teeth includes a tooth body and a tooth tip extending from a distal end of the tooth body in a circumferential direction. The rotor includes a rotor yoke arranged around the stator core, and a permanent magnet arranged on an inner wall surface of the rotor yoke to form a plurality of magnetic poles. Inner surfaces of the magnetic poles face the outer surfaces of the tooth tips with an interstitium formed between them to allow the rotor to rotate relative to the stator.

Preferably, the gap is a symmetrical gap so that the rotor is capable of being started bi-directionally.

Preferably, the interstice is a symmetrical uneven interstice and the rotor is capable of being positioned in an initial position by the magnetic field of leakage generated by the rotor permanent magnet interacting with the stator tooth tips.

Preferably, a radial interstitial width corresponding to each magnetic pole is symmetrical with respect to a circumferential midline of the magnetic pole. Preferably, the midline extends along a radial direction of the rotor.

Preferably, an interstitial radial width associated with each magnetic pole progressively increases from a central portion toward the circumferential ends of the magnetic pole, and an interstitial radial width associated with each magnetic pole is symmetrical with respect to one. central geometric axis of the magnetic pole along the circumferential direction.

Preferably, the drive mechanism includes a two-stage belt drive, which includes a first drive belt, a drive wheel, and a second drive belt. Opposite ends of the first drive belt are respectively connected to a single-phase external rotor brushless motor rotary shaft and drive wheel so that the single-phase external rotor brushless motor drives the drive wheel to rotate, and opposite ends of the second drive belt are respectively attached around the drive wheel and the drive wheel so that the drive wheel drives the drive wheel to rotate.

[010] Preferably, a transmission ratio of the rotary shaft of the single-phase external rotor brushless motor to the drive wheel is 2: 1, and / or a transmission ratio of the drive wheel to the drive wheel is 10: 1.

Preferably, an external diameter of the single-phase external rotor brushless motor is 90 mm, and an axial size of the single-phase external rotor brushless motor between two opposing end surfaces thereof is 65 mm.

Preferably, a slot opening is formed between each two adjacent tooth tips, and a slot opening width in the circumferential direction is less than or equal to five times a minimum radial width of the interstice.

Preferably, a slot opening is formed between each two adjacent tooth tips, a width of the slot opening in the circumferential direction is less than or equal to three times a minimum radial width of the interstice.

Preferably, a ratio of a maximum radial width to a minimum radial interstitial width is greater than 1.5.

Preferably, the outer surfaces of the tooth tips are located on the same cylindrical surface, and a central geometry axis of the cylindrical surface is coincident with a central geometry axis of the rotor.

Preferably, the inner surface of the permanent magnetic pole is a flat surface or arcuate surface, with a pole-arc coefficient greater than 0.75.

[017] In another aspect, a washing machine is provided which includes a drum, a single-stage external rotor brushless motor and a motor-driven transmission mechanism. The single-stage external rotor brushless motor is configured to drive the washer drum to rotate through the drive mechanism. The single-phase external rotor brushless motor includes a stator and a rotor. The stator includes a stator core and windings wound around the stator core. The stator core includes a breech and a plurality of teeth extending outward from the breech. Each of the teeth includes a tooth body and a tooth tip extending from a distal end of the tooth body in a circumferential direction. The rotor includes a rotor yoke arranged around the stator core, and a permanent magnet arranged on an inner wall surface of the rotor yoke to form a plurality of magnetic poles. The inner surfaces of the magnetic poles face the outer surfaces of the tooth tips with an interstice formed between them to allow the rotor to rotate relative to the stator, and the drive mechanism includes a two-stage belt drive.

Preferably, the gap is a symmetrical gap so that the rotor is capable of being started bi-directionally.

Preferably, the interstice is a symmetrical uneven interstice and the rotor is capable of being positioned in an initial position where a midline of the stator core tooth tip is closest to a midline of an area between two poles. adjacent magnetic lines than midlines of the two adjacent magnetic poles.

[020] In various embodiments of the present invention, the drive apparatus for the washer adopts a single-phase external rotor brushless motor, the motor stator core has small slot openings or magnetic bridges, and the interstitium is optimally configured as a symmetrical interstice. Therefore, the size and weight of the engine is reduced.

BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 is a perspective view of a drive apparatus according to one embodiment.

Fig. 2 illustrates a single-phase external rotor brushless motor of the drive apparatus of Fig. 1.

Fig. 3 is a sectional view of the single-phase external rotor brushless motor of Fig. 2 taken along a radial direction.

Fig. 4 is a sectional view of the single-phase external rotor brushless motor of Fig. 3 taken along an axial direction.

Fig. 5 is an enlarged view of the dotted box portion of Fig. 3.

Fig. 6 illustrates a single phase external rotor brushless motor stator core of Fig. 2.

Fig. 7 illustrates a single-phase external rotor brushless motor isolation support of Fig. 2.

Fig. 8 is an assembled view of the stator core of Fig. 6 and the insulating support of Fig. 7.

Fig. 9 illustrates the rotor in the neutral position when the single-phase external rotor brushless motor of Fig. 2 is not energized.

Fig. 10 illustrates the rotor in the home position when the single-phase external rotor brushless motor of Fig. 2 is not energized.

Fig. 11 illustrates a stator core of a motor according to a second embodiment of the present invention.

Fig. 12 illustrates a stator core of a motor according to a third embodiment of the present invention.

[13] Fig. 13 and Fig. 14 illustrate a rotor of an engine according to another embodiment of the present invention.

Fig. 15 illustrates a motor stator according to another embodiment of the present invention.

Fig. 16 illustrates a rotor of a motor according to another embodiment of the present invention.

[17] Fig. 17 illustrates an engine according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to Fig. 1, a washer (not shown) according to one embodiment of the present invention includes a drive apparatus 100 for driving a rotating washer drum. The drive apparatus 100 includes a single phase motor 90 (Figure 2) and a transmission mechanism. Preferably, the drive mechanism is a two-stage belt drive mechanism, which includes a first drive belt 91, a drive wheel 93, a second drive belt 95, and a drive wheel 97. Opposite ends of the first drive belt 91 are attached about a rotary axis of single phase motor 90 and drive wheel 93, respectively, so that single phase motor 90 drives drive wheel 93 to rotate. The transmission between the motor 90 and the transmission wheel 93 preferably has a transmission speed ratio of 2: 1. In particular, a pulley 94 is mounted to a rotary motor shaft to rotate together with rotary shaft 21, and the drive belt 91 is attached around the pulley 94 and one end of the drive wheel 93. Opposite ends of the second belt The drive shafts 95 are respectively attached around another end of the drive wheel 93 and the drive wheel 97, so that the drive wheel 93 can drive the drive wheel 97 to rotate. The transmission between drive wheel 93 and drive wheel 97 preferably has a transmission speed ratio of 10: 1. The drive wheel 97 is configured to drive a washer drum to rotate. The drive apparatus 100 adopts a two stage transmission including the first drive belt 91 and the second drive belt 95, which achieves a high drive ratio and improved stability using the belt drive. It should be understood that the drive apparatus may be configured to achieve another transmission ratio according to needs in other embodiments.

[038] The present invention preferably adopts a single-phase external rotor brushless motor 90, which reduces the size and weight of the motor. Figs 2 to Fig. 4 illustrate one embodiment of the single phase external rotor motor. The single-phase external rotor brushless motor includes a stator 10 and a rotor 20 surrounding the stator 10. In the illustrated embodiment, the single-phase external rotor brushless motor has an outer diameter of 90 mm. It should be understood that the single-phase external rotor brushless motor may be of another suitable size as required.

Stator 10 includes a stator core 11 made of a conductive magnetic material such as iron, an insulation support 13 attached around the stator core 11, and windings 15 wound around the insulation support 13.

Referring also to Figs. 3 to Fig. 6, the stator core 11 includes an annular portion 110, i.e. a stator breech disposed at a center of the stator core 11, and a plurality of teeth. extending radially and outwardly of the annular portion 110. A winding slit is formed between each two adjacent teeth. Each tooth includes a tooth body 112 and a tooth tip 114 extending from a distal end of the tooth body 112 along a circumferential direction. Preferably, winding 15 comprises a plurality of coils each wound only on the tooth body 112 of a single tooth and thus no coil is overlapped. Each two adjacent tooth tips 114 define between them a slot opening 115 communicating with a corresponding winding slot. In one embodiment, each slot opening 115 has the same width in the circumferential direction. That is, the prongs 114 are arranged equally along the circumferential direction. In one embodiment, each tooth is symmetrical with respect to an engine radius passing through a center of the tooth body of that tooth. Preferably, the tooth tips have the same circumferential width. It should be understood that the size of each slot opening 115 may be different and the circumferential size of each tooth tip may also differ according to need.

[041] Annular portion 110 is generally a hollow shaped cylinder. A through hole 111 is defined through a central portion of annular portion 110 along an axial direction. As shown in Figs. 2 through Fig. 4, the stator 10 further includes a base 16 and a bearing bracket 17 formed on base 16. Base 16 is generally circular disc shaped. The bearing support 17 extends perpendicularly from a central portion of the base 16 to fixate the stator core 11 thereon. Specifically, the bearing bracket 17 is inserted through the through hole 111 of the annular portion 110 of the stator core 11. The bearing bracket 17 defines therein a shaft bore for rotatably mounting a rotor shaft 21 of the rotor 20 therein.

The tooth body 112 extends radially from an outer wall surface of the annular portion 110, and the tooth bodies 112 are arranged equally along the circumferential direction of the annular portion 110. Each tooth body 112 has the tooth tip 114 formed at the radial distal end thereof. In one embodiment, the prong 114 is symmetrical with respect to a motor radius passing through a center of the prong 112. Referring also to Fig. 5, an outer surface 117 of the prong 114, i.e. a surface facing rotor 20 is an arcuate surface. In one embodiment, the outer surfaces 117 of the prongs 114 are located on the same cylindrical surface that has a central geometry axis coincident with a central geometry axis of the rotary axis 21. An internal surface 118 of the prongs 114, i.e. a surface facing toward annular portion 110 is generally a flat surface.

[043] In some embodiments, the notches 116 are formed in corner connection areas between the tooth tip 114 and the tooth body 112. The provision of the notches 116 facilitates flexion of the tooth tip 114 relative to the tooth body 112 and prevents creasing during the stator core bending process 114 of the stator core. Specifically, two wing parts of the prong 114 on opposite sides of the tooth body 112 extend radially in an initial state, such that the width of the slot opening 115 of the winding slot may be widened to facilitate winding of the windings 15. After winding is completed, the two wing parts of the prong 114 are flexed inwardly around the notches 116 to a position end using a tool. It should be understood that in some embodiments, the notch 116 may be formed only in a corner connection area between the tooth body 112 and the wing portion of the tooth tip 112 on a single side of the tooth body 112.

With reference to Figs 7 and Fig. 8, the isolation support 13 includes an upper support portion 131 and a lower support portion 133. The upper support portion 131 and the lower support portion 133 cover the core. of stator 11 from opposite axial ends thereof, respectively.

The upper bearing portion 131 and the lower bearing portion 133 are substantially the same in shape and construction, and are disposed opposite one another. Each of the upper bearing portion 131 and the lower bearing portion 133 includes a ring portion 130 attached around the annular portion 110 of the stator core 11, glove portions 132 attached around the tooth bodies 112, and portion portions. resistor 134 resisting the inner surfaces of the prongs 114. The ring portion 130 is generally circular tubular in shape, surrounding the outer wall portion of the annular portion 110 of the stator core. An annular end flange 136 extends inwardly from an axial top end of ring portion 130. End flange 136 covers an end end face of annular portion 110. A side wall of ring portion 130 forms a plurality of openings (unlabeled) in which the glove portions 132 are arranged. The opening allows the tooth body 112 to pass therethrough. The glove portion 132 also has end surfaces and side surfaces corresponding to the end surface and side surfaces of the tooth body 112. The glove portion 132 covers the end surfaces and two side surfaces of the tooth body 112. As described herein. , the end surfaces of the tooth body 112 refer to a top surface and a bottom surface of the tooth body 112 in the axial direction of the motor, and the side surfaces of the tooth body 112 refer to the two surfaces which are parallel to the radial direction. It should be understood that the glove portion 132 of the upper bearing portion 131 covers the top surface and two side surfaces of the tooth body 112, and the glove portion 132 of the lower bearing portion 133 covers the bottom surface and two tooth body side surfaces 112. Upper support portion 131 and lower support portion 133 substantially cover the entire side surfaces and end surfaces of tooth body 112 to isolate stator core 11 from windings 15.

Resistance portion 134 is formed by flexing a radial distal end of the glove portion 132 along the circumferential direction, which resists against the inner surface 118 of a corresponding tooth tip 114.

Additionally, a flexed plate 135, 137 is disposed at one axial end of the resisting portion 134. The flexed plate 135, 137 at least partially covers an end surface of the axial end portion of the tooth tip 114. In particular bent plate 135 is disposed at an axial top end of the resisting portion 134 of the upper bearing portion 131, which at least partially covers an axial top end surface of a corresponding tooth tip 114; the flexed plate 137 is disposed at a bottom axial end of the resisting portion 134 of the lower bearing portion 133, which at least partially covers a bottom axial end surface of a corresponding tooth tip 114.

Referring to Figs. 2 through Fig. 4, the rotor 20 includes a rotary shaft 21 passing through the annular portion 110, a rotor breech 22 fixedly connected with the rotary shaft 21, and a permanent magnet 24 disposed in a internal wall surface of rotor breech 22 to form a plurality of permanent magnetic poles 24. In this embodiment, permanent magnet 24 includes multiple divided magnets, each forming a permanent magnetic pole 24. In an alternative embodiment, the permanent magnet may be formed on an integral ring magnet as shown in Fig. 16. Ring magnet 24 comprises a plurality of sections, each section forming a permanent magnetic pole 24. In one embodiment, an internal surface 241 of permanent magnet 24 is a flat surface. so that the manufacture of permanent magnet 24 can be simplified. It should be understood, however, that the inner surface of permanent magnet 24 may also be an arcuate surface. In one embodiment, the permanent magnet 24 pole-arc coefficient, that is, a ratio of the actual span angle of the permanent magnet 24 along the circumferential direction to the 360 degree quotient divided by the number of rotor poles, is greater. than 0.75, which can improve torque characteristics without current and enhance motor efficiency.

With reference to Fig. 4, the rotary shaft 21 is rotatably disposed in the shaft bore of the bearing bracket 17. For example, the rotary shaft 21 is rotatably supported in the bearing bracket 17 by a bearing. The rotor yoke 22 is generally barrel-shaped covering the stator core 11. The rotor yoke 22 includes an end plate 221 fixedly connected to the rotary shaft 21, and an annular side wall 222 extending from the contact plate. The end plate 221 is disposed opposite the base 16, with an interstitial formed between an axial end of the sidewall 222 and the base 16. The end plate 221 and the base 16 each have a distal end surface. stator core and motor magnets. In this embodiment, the axial size of the motor between the two end surfaces thereof is d65 mm. End plate 221 therein forms a plurality of windows to allow external air to enter and cool an interior of the engine. During motor operation, rotor breech 22 and permanent magnet 24 rotate relative to the stator under interaction between the magnetic fields of permanent magnet 24 and the stator.

[050] In some embodiments, the number of permanent magnetic poles 24 may be the same or have a multiple relationship to the number of teeth. For example, the number of teeth is two or three times the number of permanent magnetic poles. In this embodiment, rotor 20 includes eight permanent magnets forming respectively eight permanent magnetic poles, stator 10 includes eight stator teeth, and a total of eight winding slots are formed between adjacent teeth, thus forming an 8-pole and 8-slot motor. . In one embodiment, the stator windings are electrically connected and powered with single phase current by a single phase brushless DC motor drive, thus forming a single phase DC brushless motor. It should be understood that the motor of the present invention may be used as a single phase permanent magnet synchronous motor where the stator windings are connected to a single phase alternating current power supply.

As shown in Fig. 5, the inner surfaces 241 of the permanent magnetic poles 24 face the outer surface 117 of the prong 114, with an interstitium 119 formed therebetween. A radial width of the interstitium 119 varies along a circumferential direction of the permanent magnetic pole 24, thereby forming an uneven interstice. The radial width of interstitial 119 progressively increases from a circumferential means toward opposite circumferential ends of an inner surface 117 of the permanent magnetic pole 24. Preferably, the corresponding interstice with each magnetic pole 24 is symmetrical about the circumferential midline of the pole. 24 to form, therefore, a symmetrical uneven interstice so that the rotor is capable of being started bi-directionally. A radial distance between a circumferential center point of the inner surface of the permanent magnetic pole 24 and a cylindrical surface where the outer surface of the tooth tip 114 is located is the maximum radial width G2 of interstitial 119. Preferably, a radial width ratio maximum for minimum radial width of interstitial 119 is greater than 1.5, ie G2: G1> 1.5. More preferably, the ratio of maximum radial width to minimum radial width of interstitial 119 is greater than 2, i.e. G2: G1> 2.

[052] A width D (generally referring to the minimum width of slot aperture 115 in the circumferential direction) of slot aperture 115 is greater than 0, but less than or equal to five times the minimum radial width of interstitial 119, i.e. is, 0 <D <5G1. In one embodiment, the radial width D of slot aperture 115 is equal to or greater than the minimum radial width of interstitial 119, but less than or equal to three times the minimum radial width of interstitial 119, that is, G1 <D < 3G1. Alternatively, adjacent tooth tips 114 may be connected by a narrow tip 115a with a large magnetic resistance as shown in Fig. 15.

Referring also to Figs. 9 and Fig. 10, when the motor is not energized, permanent magnet 24 of rotor 20 produces an attractive force that attracts stator teeth 10. Figs. 9 and Fig. 10 show the rotor 20 in different positions. Specifically, Fig. 9 shows rotor 20 in a neutral position (that is, a center of the rotor magnetic pole is aligned with a center of the stator tooth tip). Fig. 10 shows the rotor 20 in an initial position (ie, the rotor stop position when the engine is not energized or shut down). As shown in Fig. 9 and Fig. 10, the magnetic flux of the magnetic field produced by the magnetic pole of rotor 20 passing through stator 10 is Φ1 when rotor 20 is in the neutral position, the magnetic flux of the magnetic field produced by the magnetic pole of rotor 20 passing through stator 10 is Φ2 when rotor 20 is in the home position, and Φ2> Φ1 and ο path of Φ2 is less than Φ1 and resistance of Φ2 is therefore less than from Φ1. Therefore, the rotor 20 can be positioned in the home position when the engine is not energized, thus avoiding the neutral position and consequently preventing the failure to start the rotor when the engine is energized. In this embodiment, the rotor 20 stops at the starting position shown in Fig. 10 when the engine is not energized or shut down. In this initial position, a centerline of the stator core tooth tip 112 is aligned with a centerline of the area between two adjacent rotor magnetic poles 24. In this embodiment, the magnetic poles 24 are permanent magnetic poles and the centerline of each tooth tip 112 of the stator core is aligned with the neutral area centerline between two adjacent rotor magnetic poles 24. This position deviates as much from the neutral position, which can effectively prevent failure to start the rotor when The engine is energized. Due to other factors such as friction in practice, the centerline of the stator core tooth body 112 may deviate from the centerline of the area between two adjacent rotor magnetic poles 24 by an angle such as 0 to 30 degrees electric, but the position of stop is still far from neutral. That is, when the motor is not energized, the rotor stops at an initial position where the midline of the stator core tooth tip is closer to the midline of the area between two adjacent magnetic poles than the midline of the two magnetic poles. adjacent 24.

[054] In the above embodiments of the present invention, the rotor may be positioned in the initial position by deviating from the neutral position by the magnetic leakage field produced by the permanent magnetic rotor pole 24 attracting with the stator core tooth tips. Leakage magnetic field produced by rotor permanent magnetic pole 24 does not pass through tooth bodies 112 and windings. The non-current torque of the single-phase permanent magnet brushless motor configured as such can be effectively suppressed so that the motor has improved efficiency and performance. Experiments show that a peak torque of no current of a single-phase external rotor brushless DC motor configured as above (calculated torque is 1 Nm, calculated rotation speed is 1000 rpm, and core stack height stator length is 30 mm) is less than 80 mNm. The engine of the present invention may be designed with bidirectional starting capability as required. For example, bidirectional rotation can be achieved using two position sensors such as Hall sensors and an associated controller. It can also be designed to start in one direction, in which case only one position sensor is required.

In addition, a distance between the end plate 221 of the single-phase external rotor brushless motor and the end surface of the base 16 away from the end plate 221 is 65 mm.

Fig. 11 illustrates a stator core 40 of a motor according to another embodiment of the present invention. Stator core 40 differs from stator core 11 of the above embodiment in: stator core 40 of the present embodiment includes a plurality of individual tooth sections 41 which are connected to one another. Each tooth section 41 includes a breech section 410, a tooth body 412 extending radially outwardly from the breech section 410, and a tooth point 414 extending from a distal end of the tooth body 414 at. a circumferential direction. The tooth sections 41 are arranged along the circumferential direction to collectively form stator core 40. The breech sections 410 of the tooth sections 410 collectively form an annular breech. The breech sections 410 may be interlocked by a concave-convex interlocking structure formed therebetween. In this embodiment, a protrusion 415 is formed on one circumferential side of each breech section 410, and a recess 417 is formed on the other circumferential side of each breech section 410. The protrusion 415 of each breech section 410 is snapped into place. recess 417 of another adjacent breech section 410, and recess 417 of each breech section 410 receives protrusion 415 from another adjacent breech section 410, so that all tooth sections 41 are connected in one entire body. Alternatively, tooth sections 410 may have flat contactor surfaces that are attached to each other by welding. Since stator core 40 can be formed by interconnecting individual tooth sections 41, winding can be performed prior to connecting tooth sections 41 over an entire body. Therefore, the slot opening between the prongs 414 may be reduced in size without affecting the winding process.

Fig. 12 illustrates a stator core 50 according to another embodiment of the present invention. Stator core 50 differs from stator core 11 of the first embodiment in that the stator core 50 of the present embodiment includes first teeth 51 integrally formed with breech 510 and second teeth 52 formed separately. The second teeth 52 are snap-fitted to the breech 510, and the first teeth 51 and the second teeth 52 are arranged alternatively along the circumferential direction. In one embodiment, the second teeth 52 are inserted into the breech portion 510. The breech portion 510 has a plurality of insertion slots 511. A radial inner end of the second tooth 52 has an insertion portion 522 that matches with the insert slot. insert 511 in format. In one embodiment, the insertion slot 511 is a dovetail shaped slot. The stator core 50 of this embodiment includes second individual teeth 52 which may be inserted into breech 510 after winding is completed. Therefore, the gap between the tooth tips can be reduced in size without affecting the winding process.

Fig. 13 and Fig. 14 illustrate a rotor 60 according to another embodiment of the present invention. Rotor 60 differs from rotor 20 of the first embodiment in that rotor 60 additionally includes a packing portion 65. Specifically, rotor 60 is packaged by placing rotor breech 62 and permanent magnets 64 into a mold cavity and injecting plastic into the cavity. of mold.

Fig. 17 illustrates an engine according to another embodiment of the present invention. In this embodiment, the rotor 70 includes permanent magnets 26 and magnetic members 24 which are alternately spacedly arranged in the circumferential direction. Permanent magnets 26 are magnetized in the circumferential direction of the rotor. Adjacent permanent magnets 26 have opposite polarities. Magnetic members 24 may be made of a hard magnetic material such as ferromagnet or rare earth magnets, or a soft magnetic material such as iron. The magnetic member 24 has a progressively decreasing thickness from a circumferential means to two circumferential sides thereof. A minimum thickness of the magnetic member 24, i.e. the thickness on its circumferential sides, is substantially the same as that of permanent magnet 26. Preferably, the inner circumferential surface of the magnetic member 24 facing the stator is a flat surface that protrudes. extends parallel to a tangential direction of an external surface of the stator. As such, the inner circumferential surfaces of the permanent magnets and the inner circumferential surfaces of the magnetic members collectively form the inner surface of the rotor which is a symmetrical polygon in a radial cross section of the rotor 70. The inner surfaces of the permanent magnets 26 and the inner surfaces of the magnetic members 24 collectively form a polygonal inner surface of the rotor 70. The stator 10 and the rotor 70 form between them a symmetrical uneven interstice, which has a size that progressively increases from a circumferential means to two circumferential sides of the magnetic member 24, and reaches the maximum width Gmax at the position corresponding to permanent magnet 26. When the motor is de-energized, the rotor 50 is capable of being positioned in an initial position by the magnetic leakage field generated by the permanent magnets 26 forming permanent magnetic poles, the magnetic field. leakage compree comprising a plurality of flow circuits, each passing through a corresponding permanent magnetic pole 26, two adjacent magnetic members 24 on opposite sides of the corresponding magnetic pole 26 and a corresponding stator prong 114 near the corresponding permanent magnetic pole 26.

Fig. 18 illustrates an engine according to another embodiment of the invention. The stator tips 114 of the stator 10 are connected to each other by magnetic bridges 116 in the circumferential direction, and the entire outer surface of the stator 10, that is, the outer surface 117 of the tooth tip 114 is a closed cylindrical surface. The inner surface of the rotor 80, that is, the inner circumferential surfaces 241 of the permanent magnets 24, is located on a cylindrical surface coaxial with the outer circumferential surface 117 of stator 10. The outer circumferential surface 117 of stator 10 and the inner circumferential surface 241 of rotor 80 define an equal symmetrical interstice. The outer circumferential surface 117 of the prong 114 is provided with positioning grooves 42, which makes the prong 114 have an asymmetrical structure, thus ensuring that when the rotor 80 is stopped, a center line of the area between two magnets Adjacent permanent members 54 deflect an angle to a centerline of the stator prong tooth tip 114. Preferably, when the rotor is stopped, the stator positioning slot 42 is aligned with the center line of the two magnets adjacent permanent lights 24 of rotor 80, which allows rotor 80 to start successfully each time the motor is energized. Understandably, in this embodiment, the stator prongs 114 may be separated from each other by means of a narrow slot opening in the circumferential direction.

[061] The washer drive 100 adopts single-phase outboard motor brushless motor 90, motor stator core 11, 40, 70, 80 has small slot opening, and interstitial 119 is optimally configured as a symmetrical uneven interstice. Therefore, the size and weight of engine 90 is reduced.

Although the invention is described with reference to one or more preferred embodiments, it should be recognized by those skilled in the art that various modifications are possible. For example, the rotor magnetic poles may also be of an integrated type rather than the split type as described in the above embodiments, the number of slots and poles may range from 2 poles and 2 slots to N poles and N slots without departing from the scope. of the present invention. Therefore, the scope of the invention should be determined by reference to the following claims.

Claims (18)

1. A washing machine drive unit, characterized in that it comprises a single-phase external rotor brushless motor and a motor-driven transmission mechanism, the single-phase external rotor brushless motor configured to drive a washer drum for rotating through the transmission mechanism, the single-stage external rotor brushless motor comprising a stator including a stator core and windings wound around the stator core, the stator core including a breech and a a plurality of teeth extending outward from the breech, each of the teeth including a tooth body and a tooth tip extending from a distal end of the tooth body in a circumferential direction; and a rotor including a rotor yoke arranged around the stator core, and a permanent magnet arranged on an inner wall surface of the rotor yoke to form a plurality of magnetic poles, the inner surfaces of the magnetic poles facing the outer surfaces. the tooth tips with an interstitium formed between them to allow the rotor to rotate relative to the stator. The drive device for a washing machine according to claim 1, characterized in that the gap is a symmetrical gap so that the rotor is capable of being started bi-directionally. A washing machine drive according to claim 1 or 2, characterized in that a radial interstitial width corresponding to each magnetic pole is symmetrical with respect to a circumferential midline of the magnetic pole. A washing machine drive according to any one of claims 1 to 3, characterized in that the interstice is a symmetrical uneven interstice and the rotor is capable of being positioned in an initial position by a magnetic field of leakage generated by the rotor permanent magnet interacting with the stator tooth tips. A washing machine drive according to claim 4, characterized in that a radial width of the interstitium corresponding to each magnetic pole increases progressively from a central portion towards the circumferential ends of the magnetic pole. Drive for a washing machine according to any one of claims 1 to 3, characterized in that the inner surfaces of the magnetic poles and the outer surfaces of the tooth tips are respectively located on two coaxial cylindrical surfaces one with the other, the outer surface of each of the tooth tips forming a locating groove. A washing machine drive according to any one of claims 1 to 6, characterized in that the drive mechanism includes a two-stage belt drive. Washing machine drive according to claim 7, characterized in that the drive mechanism includes a first drive belt, a drive wheel, and a second drive belt, opposite ends of the first belt. The drive shafts are respectively connected to a single-phase external rotor brushless motor rotary shaft and drive wheel so that the single-phase external rotor brushless motor is capable of driving the drive wheel to rotate, and ends Opposites of the second drive belt are respectively attached around the drive wheel and the drive wheel so that the drive wheel is capable of driving the drive wheel to rotate. Washing machine drive according to Claim 8, characterized in that a transmission ratio of the rotary axis of the single-phase external rotor brushless motor to the transmission wheel is 2: 1, and / or a transmission ratio of the drive wheel to the drive wheel is 10: 1. Washing machine drive according to any one of claims 1 to 9, characterized in that an external diameter of the single-phase external rotor brushless motor is 90 mm, and an axial size of the motor without Single-phase external rotor brush between two opposite end surfaces thereof is 65 mm. Drive for a washing machine according to any one of claims 1 to 9, characterized in that a slot opening is formed between each two adjacent tooth tips and a width of the slot opening in the circumferential direction. is less than or equal to five times a minimum radial width of the interstitium. Drive for a washing machine according to any one of claims 1 to 9, characterized in that a slot opening is formed between each two adjacent tooth tips, a width of the slot opening in the circumferential direction is less than or equal to three times a minimum radial width of the interstitium. A washing machine drive according to any one of claims 1 to 5, characterized in that a ratio of a maximum radial width to a minimum radial width of the interstitial is greater than 1.5. Drive for a washing machine according to claim 1, characterized in that the outer surfaces of the tooth tips are located on the same cylindrical surface, and a central geometric axis of the cylindrical surface is coincident with a geometric axis. rotor center. A washing machine drive according to any one of claims 1 to 9, characterized in that the inner surface of the permanent magnetic pole is a flat surface or arcuate surface with a pole-to-arc coefficient greater than 0.75. 16. Washer, characterized in that it comprises a drum, a single-phase external rotor brushless motor and a motor-driven transmission mechanism, the single-phase external rotor brushless motor configured to drive the drum of the washer for rotating through the drive mechanism, the single-stage external rotor brushless motor comprising: a stator including a stator core and windings wound around the stator core, the stator core including a breech and a plurality of teeth extending outward from the breech, each of the teeth including a tooth body and a tooth tip extending from a distal end of the tooth body in a circumferential direction; and a rotor including a rotor yoke arranged around the stator core, and a permanent magnet arranged on an inner wall surface of the rotor yoke to form a plurality of magnetic poles, the inner surfaces of the magnetic poles facing the outer surfaces. the tooth tips with an interstitium formed between them to allow the rotor to rotate relative to the stator, the transmission mechanism including a two-stage belt drive. Washing machine according to claim 15, characterized in that the interstitial is a symmetrical interstitial such that the rotor is capable of being started bi-directionally. Washer according to claim 16, characterized in that the interstitium is a symmetrical uneven interstitium and the rotor is capable of being positioned in an initial position where a midline of the stator core tooth tip is closer to a midline of an area between two adjacent magnetic poles than midlines of two adjacent magnetic poles.