CN201533229U

CN201533229U - brushless dc motor

Info

Publication number: CN201533229U
Application number: CN2009202371636U
Authority: CN
Inventors: 邹定锦
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-10-06
Filing date: 2009-10-06
Publication date: 2010-07-21
Anticipated expiration: 2019-10-06

Abstract

The utility model discloses a brushless DC motor, which comprises a bracket, a bearing, a stator part and a rotor part, wherein the stator part comprises a stator core, a coil winding, an insulated wire rack and a wiring terminal, wherein the stator is designed to be a novel and movable buckle point structure, the stator is assembled to be a 360-degree full circle through linkage buckling of the movable buckle points, the full circle can be opened for 360-degree through free folding in reverse direction, the winding is easy, the wire arranging quality after wiring is good, an insulating line frame is mounted on each stator, the wire head and the wire tail are fixed in a connecting terminal hole after wiring, and the final jointing after the assembly of the stator is fixed through arc welding; the rotor part comprises a rotating shaft, a rotor core and a permanent magnet; the rotor core is fixed on the rotating shaft; and the permanent magnet is fixed on the excircle of the rotor core. The bearing, a gasket and a bearing clamp are arranged at the junction part of the bracket and the rotating shaft; and the stator core is combined with the bracket through bolts. The brushless DC motor provided by the utility model has the characteristics of wide speed regulation, small volume, high efficiency, low noise, and long service life of the complete machine; and the small errors of rotational speed under a steady state.

Description

Brshless DC motor

Technical field

The utility model relates to a kind of brshless DC motor, is specifically related to the novel brshless DC motor of a kind of use on intelligent soy milk grinder.

Background technology

DC motor is widely used with its good governor control characteristics.Shortcomings such as but DC motor is owing to need the mechanical switching device, and poor reliability needs often to safeguard, produces electromagnetic interference during commutation, and noise is big and influenced its further application.Along with power electronic technology and computer-controlled development, the permanent magnet direct current motor that replaces mechanical switching with electronic commutation arises at the historic moment.Compare with other motor, the maximum characteristics of brushless DC motor are that the switch converters with the dislocation signal controlling has substituted the mechanical switching device of being made up of brush and commutator the brush DC motor, make the good speed governing and the control characteristic of its existing DC motor, there is ac motor structure simple again, reliable, advantage such as easy to maintenance.Brushless, permanently excited direct current motor can dwindle motor volume owing to adopt permanent-magnet steel, reduces loss, improves electromechanical efficiency.China's rare earth resources is abundant, and researching and developing permanent magnet motor energetically is the important directions of electromechanics trade development.

Summary of the invention

It is a kind of simple in structure that the purpose of this utility model will provide exactly, and volume is little, the reliability height, and noise is low, the brshless DC motor of the long service life of complete machine.

The technical solution of the utility model is as follows: brshless DC motor, comprise support, bearing, stator department, rotor portions, it is characterized in that: described stator department is made up of stator core, coil windings, insulation coil holder, binding post, stator design becomes novel movable button dot structure, stator is by buckleing the 360 ° of full circle that are assembled into a little all linked with one another, can freely fold along reverse 360 ° and come, coiling easily, coiling back winding displacement quality is better; On every groove stator the insulation coil holder is installed, the end of a thread line tail is fixed in the binding post hole behind intact line, and the last seam after the stator assembling is fixed with inferior arc welding; Described rotor portions is by rotating shaft, the rotor heart, and permanent magnet is formed; The rotor heart is fixed in the rotating shaft, and permanent magnet is fixed on rotor heart cylindrical.

Described support and rotating shaft junction are provided with bearing, pad and bearing folder.

Described stator core is by screw and described holder combination.

The beneficial effects of the utility model are: brushless DC motor is in the power network fluctuation scope that allows, and below the overload capacity that allows, its steady-state speed and instruction rotating speed differs about 1%, and can be implemented in permanent torque operation in the speed adjustable range; Because the excitation of brushless DC motor derives from permanent magnet, need not draw exciting current from electrical network the asynchronous machine so do not resemble; Owing to do not have alternating flux in the rotor, not only there is not copper loss but also do not have iron loss on its rotor, so efficient is than high by about 10% with capacity asynchronous motor, in general, the power of brushless DC motor energy pointer (η cos θ) ratio is with the high 12%-20% of capacity threephase asynchronous; Because brushless DC motor is with autocontrol operation, on rotor, add the startup winding so can not resemble in addition the synchronous motor of heavy load starting under the frequency control, can when load changing, not produce yet and vibrate and step-out.In brief, the utility model brshless DC motor has that wide range speed control, small size, high efficiency, noise are low, characteristics such as the long service life of complete machine and steady-state speed error are little.

Description of drawings

Fig. 1 is a basic structure schematic diagram of the present utility model;

Fig. 2 is the structural representation of stator core of the present utility model (before launching);

Fig. 3 is the structural representation of stator core of the present utility model (launching the back);

Fig. 4 is an operation principle fundamental block diagram of the present utility model.

Among the figure: 1, rotating shaft 2, bearing 3, bearing folder 4, support 5, insulation coil holder 6, binding post 7, stator core 8, pad 9, the rotor heart 10, permanent magnet 11, coil windings 12, screw 71, portion's tooth 72, yoke portion 73, notch 74, movable button point 75, inferior arc-welding point 76, riveting are buckled a little

Embodiment

Below in conjunction with accompanying drawing, the utility model is further described by embodiment:

As shown in Figure 1, Figure 2, Figure 3 and Figure 4, the utility model brshless DC motor, comprise support 4, bearing 2, stator department, rotor portions, described stator department is made up of stator core 7, coil windings 11, insulation coil holder 5, binding post 6, stator design becomes the novel movable button to put 74 structures, and stator is put 74 by movable button and all linked with one anotherly is assembled into 360 ° of full circle, can freely fold along reverse 360 ° and come, coiling easily, coiling back winding displacement quality is better; Insulation coil holder 5 is installed on every groove stator, and the end of a thread line tail is fixed in binding post 6 holes behind intact line, and the last seam after the stator assembling is fixed with inferior arc welding; Described rotor portions is by rotating shaft 1, the rotor heart 9, and permanent magnet 10 is formed; The rotor heart 9 is fixed in the rotating shaft 1, and permanent magnet 10 is fixed on the rotor heart 9 cylindricals.

Described support 4 is provided with bearing 2, pad 8 and bearing folder 3 with rotating shaft 1 junction.

Described stator core 7 is by screw 12 and described support 4 combinations.

The operation principle of the utility model brshless DC motor is as follows:

Main circuit is a typical voltage-type AC-DC-AC circuit, and inverter provides the symmetrical alternation square wave of constant amplitude equifrequency 5-26KHZ modulating wave.

Permanent magnet N-S is exchange alternately, make position transducer produce the U of 120 ° of phase differences, V, the W square wave, in conjunction with just/reverse signal produces effective six state encoding signals: 101,100,110,010,011,001, handle generation T1-T4 conducting by logic module, the T1-T6 conducting, the T3-T6 conducting, the T3-T2 conducting, the T5-T2 conducting, the T5-T4 conducting, that is to say DC bus-bar voltage is added in A+B-successively, A+C-, B+C-, B+A-, C+A-, on the C+B-, the rotor revolution is crossed a pair of N-S utmost point like this, and the T1-T6 power tube promptly becomes the conducting successively of six kinds of states by fixed combination.Under every kind of state, the energising of two phase windings is only arranged, change a kind of state successively, the magnetic field axis that stator winding produces is in 60 ° of electrical degrees of spatial rotational, rotor is followed the stator field rotation and is equivalent to 60 ° of electrical degree locus, rotor is on reposition, make position transducer U, V, W produce one group by agreement and newly encode, new coding has changed the conducting combination of power tube again, the magnetic field axis that stator winding the is produced 60 ° of electrical degrees that readvance, so circulation, brushless DC motor will produce continuous torque, drag load and do rotation continuously.Just because of being self, the commutation of brushless DC motor produces, rather than by the inverter forced commutation, so be also referred to as self-controlled synchronous motor.

The position transducer coding of brushless DC motor makes the leading rotor field of axial location, the two phase winding resultant magnetic fields axial location of energising, so no matter the original position of rotor wherein, motor will produce enough big detent torque starting moment, so does not need to establish in addition the startup winding on the rotor.

Because it is vertical that the stator field axis can be regarded as with rotor axis, under the undersaturated situation of iron core, the average electromagnetic torque of generation is directly proportional with winding current, and this is the electric current-torque characteristics of DC motor with separate excitation just.

The torque of motor is proportional to winding average current: Tm=KtIav (Nm)

The difference of motor two phase winding back-emfs is proportional to the angular speed of motor: ELL=Ke ω (V)

So the average current in the motor winding is: Iav=(Vm-ELL)/2Ra (A)

Wherein, Vm=δ VDC is added in average voltage between motor line, and VDC is a DC bus-bar voltage, and δ is the duty ratio of modulating wave, and Ra is every phase winding resistance.Can obtain the electromagnetic torque of DC motor thus: Tm=δ (VDCKt/2Ra)-Kt (Ke ω/2Ra)

Kt, Ke are the structural constants of motor, and ω is the angular speed (rad/s) of motor, so, when certain ω, change duty cycle, delta, just can change the electromagnetic torque of motor linearly, obtain and identical control characteristic and the mechanical property of DC motor with separate excitation armature voltage control.

The speed setting of brushless DC motor, the height that depends on speed command Vc, if the speed command maximum is+maximum speed of 5V correspondence: Vc (max) ó n max, so, the promptly corresponding suitable rotation speed n of the following any level of+5V, this has just realized the speed change setting.

After Vc sets, no matter be load variations, mains voltage variations, or variation of ambient temperature, when rotating speed is lower than the instruction rotating speed, feedback voltage Vfb diminishes, and the duty cycle, delta of modulating wave will become greatly, and it is big that armature supply becomes, the electromagnetic torque that motor is produced increases and produces acceleration, till the actual speed and instruction rotating speed of motor equates; Otherwise if the motor actual speed compares when instructing rotating speed high, δ reduces, and Tm reduces, and deceleration takes place, till actual speed and instruction rotating speed equates.We can say that brushless DC motor is in the power network fluctuation scope that allows, below the overload capacity that allows, its steady-state speed and instruction rotating speed differs about 1%, and can be implemented in permanent torque operation in the speed adjustable range.

Claims

1. brshless DC motor, comprise support, bearing, stator department, rotor portions, it is characterized in that: described stator department is made up of stator core, coil windings, insulation coil holder, binding post, and stator design becomes novel movable button dot structure, and stator is by buckleing the 360 ° of full circle that are assembled into a little all linked with one another; On every groove stator the insulation coil holder is installed, the end of a thread line tail is fixed in the binding post hole behind intact line, and the last seam after the stator assembling is fixed with inferior arc welding; Described rotor portions is by rotating shaft, the rotor heart, and permanent magnet is formed; The rotor heart is fixed in the rotating shaft, and permanent magnet is fixed on rotor heart cylindrical.

2. brshless DC motor as claimed in claim 1 is characterized in that: described support and rotating shaft junction are provided with bearing, pad and bearing folder.

3. brshless DC motor as claimed in claim 1 is characterized in that: described stator core is by screw and described holder combination.