CN1051468A

CN1051468A - The monopole asynchronous motor of meterial saving and high efficiency

Info

Publication number: CN1051468A
Application number: CN 90109335
Authority: CN
Inventors: 李成求
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-11-19
Filing date: 1990-11-19
Publication date: 1991-05-15

Abstract

The invention discloses a kind of monophase machine that does not start winding.It is to be closed by main winding and capacitor matching and produce bigger starting torque.During electric motor starting under the effect of capacitor main winding itself just do action and use.The present invention has solved the starting problem of motor under the situation of saving the starting winding, by test, starting torque reaches 2.6 times during 6 times of starting currents.This motor need mate the bigger electrolytic capacitor of capacity, can be made into the motor of 25W--4KW.

Description

The monopole asynchronous motor of meterial saving and high efficiency

The present invention relates to a kind of single-phase motor that does not start winding.Monophase machine generally all has the starting winding, and the starting winding then promptly disconnects with power supply after motor reaches certain revolution.Cause the waste in material and space at attachment devices such as motor starting winding in service and switches.The fault of motor also often appears in these attachment devices.Because each coil turn of main winding and starting winding does not wait, wire winding and inserting-coil process complexity, the copper factor of some groove is lower, influences the effective rate of utilization of iron core.

The objective of the invention is to overcome the shortcoming in the above-mentioned prior art, a kind of nothing starting winding monophase machine of every groove equal turn numbers is provided.

Task of the present invention is that following mode is finished.Have only main winding in the stator of motor, every groove equal turn numbers, the centre tap of main winding connects an electrolytic capacitor that capacity is bigger, and capacitor is connected by switch and a certain power line.During electric motor starting under the effect of capacitor main winding itself do action usefulness, capacitor disconnects by switch and power supply when the revolution of motor reaches 70% left and right sides of rated revolution.

That the present invention has is simple in structure, save material, non-damageable characteristics.By test CO ₂2.6 times of starting torques, 6 times of starting currents when the 180W bipolar machine mates 470 μ F electrolytic capacitors.The various runnabilities of motor all are up to state standards.Efficiency of motor 83%(standard 60% wherein).The starting torque of motor is directly proportional with capacitor volume, can adjust starting torque easily.The power bracket of motor is unrestricted, can be made into the motor of 40W-4KW.Because copper factor is low, the sectional area of suitable increasing lead improves efficiency of motor under the prerequisite of saving copper cash.

Describe structure of the present invention and principle in detail below in conjunction with accompanying drawing.

Fig. 1 is a basic circuit diagram of the present invention.

Fig. 2 is the oscillogram of voltage and current

Fig. 3 is the formation schematic diagram of the two poles of the earth rotating magnetic field

Fig. 4 is the cut-away view of starter

Fig. 5 is winding connection figure

Fig. 6 is the winding overhang Pareto diagram

Winding of the present invention is arranged feature: with reference to Fig. 1.With centre tap winding ad is divided into two sections of ac, bd.The adjacent arrangement of top b of the top a of winding ac and winding bd, the adjacent arrangement of not end d of not holding c and winding bd of winding ac, promptly two sections windings are spaced apart mutually.

Starting principle of the present invention is as follows: with reference to Fig. 2, Fig. 3, Fig. 4.

I among Fig. 2 ₁Be the current waveform of winding ac, I ₂It is the current waveform of winding bd.The charging and discharging currents of capacitor makes two windings produce difference between current respectively by winding ac and winding bd during electric motor starting.

Capacitor began charging when forward voltage increased.Charging current is by winding ac.(hereinafter to be referred as ac, bd).0-1/8t during this period of time because capacitor volume is big, the rate of change height of voltage, charging current is very big, at this moment the electric current of ac increases very soon.The electric current of ac reaches maximum during 1/8t, and the electric current of bd is less than the electric current of ac.Voltage reaches maximum during 1/4t.The capacitor charging finishes.The electric current of ac and bd is identical.Capacitor discharged by bd when forward voltage reduced.The electric current of bd reaches maximum during 3/8t.The electric current of ac is less than the electric current of bd.Charging current is passed through ac again during negative half period.The electric current of ac reaches maximum during 5/8t.The capacitor charging finishes during 3/4t, and the electric current of ac and bd is identical.The electric current of bd reaches maximum during 7/8t.As can be seen from the figure, during 1/8t because the electric current of ac has been formed centrally two magnetic fields in greater than bd, with a in Fig. 3～1 and c being.1/8t-1/4t during this period of time in the electric current of a and c reducing, the electric current of b and d is increasing.The rotation of magnetic field center up time direction.The magnetic line of force is up time direction cutting rotor conductor also.The electric current of two windings is identical during 1/4t, and magnetic field center rotates to the position of Fig. 3～2.The 1/4t-3/8t electric current of a and c is during this period of time still reducing, and the electric current of b and d is increasing.Magnetic field center rotates to the position of Fig. 3～3 during 3/8t.As can be seen from Figure 3, from 1/8t to 3/8t during this period of time magnetic field center rotated 90 the degree mechanical angles.Cd becomes anodal during negative half period, and ab becomes negative pole.Magnetic field center is based upon on anodal c and the negative pole a during 5/8t.Magnetic field center has rotated 90 degree mechanical angles again.Below identical with positive half cycle.The electric current of a winding is reducing at the electric current that increases another winding in same resultant magnetic field, and this is a best a kind of rotating magnetic field.This rotating magnetic field to threephase asynchronous is similar, can produce bigger starting torque.Condenser capacity size no matter, because the charging current of capacitor and discharging current be respectively by winding ac and winding bd, the difference between current of two sections windings always exists.Capacitor volume is big more, and the difference between current of two sections windings is also big more, and starting torque is also big more.

Fig. 5 is winding connection figure of the present invention, and Fig. 6 is a winding overhang Pareto diagram of the present invention.Be 16 groove bipolar machines, pitch 1-7.Solid line among the figure is the Pareto diagram of winding ac, and dotted line is the Pareto diagram of winding bd.The head end of winding ac connects the not head end of termination bd of power line, and draws tap herein and connect capacitor.Another power line of not termination of bd.

Fig. 4 is the cut-away view of starter.Capacitor and triple-pole switch are housed in the starter.The starter outside is provided with starting button and stop button.(not drawing among the figure) K ₂The capacitor of connecting.There is back-moving spring in starting button bottom.Press starting button during electric motor starting.At this moment K ₁K ₃Moving contact and power connection and pin K ₂Moving contact also do not lock by capacitor and power connection, as long as one looses one's grip starting button by back-moving spring power reposition, K ₂Moving contact and power supply disconnect.Therefore, the revolution of motor reach rated revolution about 70% after when openhanded when opening moving button, capacitor just with power supply disconnection, K ₁K ₃Moving contact still pin, motor brings into operation.When stopping, pressing by motor stop button, the K that at this moment is lockable ₁K ₃Moving contact decontroled K ₁K ₃Moving contact and power supply break away from, motor is out of service.

Claims

1, a kind of monopole asynchronous motor of meterial saving and high efficiency, comprise support, stator core, stator winding, end cap, rotor, it is characterized in that having only in the stator main winding (ad), locate to be provided with centre cap in the middle of the main winding (ad) and make main winding be divided into two sections of (ac), (bd); Winding in stator core slot (ac), (bd) space distribute the adjacent arrangement in top of the top of winding (ac) and winding (bd), the adjacent arrangement of not end of the not end of winding (ac) and winding (bd); Centre cap also has start capapcitor (c) and starting switch (K ₂)

2,, it is characterized in that the every groove number of turn of winding coil in stator core slot is identical according to the monopole asynchronous motor of claim 1 defined.

3, the described monopole asynchronous motor of claim 1 is characterized in that said centre cap draws from the not end of winding (ac) and the top of winding (bd).