CN2245301Y

CN2245301Y - High efficiency single-phase asynchronous motor

Info

Publication number: CN2245301Y
Application number: CN 94231554
Authority: CN
Inventors: 李成求
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-12-20
Filing date: 1994-12-20
Publication date: 1997-01-15
Anticipated expiration: 2004-12-20

Abstract

The utility model provides a single-phase asynchronous motor without starting windings. An intermediate tap of a main winding and a starting capacitor are connected and matched to generate relatively large starting torque. When the motor starts, the main winding can achieve the starting function under the action of the capacitor, so the motor can be started under the condition of no starting windings. The motor needs to be matched with an electrolytic capacitor with relatively large capacitance. The motor can be made into a motor with the power of 60W-750W. The single-phase asynchronous motor has the advantages of reasonable structure, simple process, remote possibility of damage, etc. The efficiency can be increased by 10-20% compared with the original standard.

Description

A kind of efficient monopole asynchronous motor

The utility model relates to a kind of single-phase motor that is not activated winding.

Monophase machine generally all has the startup winding, starts winding and then promptly disconnect with power supply after motor reaches certain revolution.Because each coil turn of main winding and startup 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 purpose of this utility model is the shortcoming that overcomes in the above-mentioned prior art, and a kind of monophase machine of nothing startup winding 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 the startup effect, when the revolution of motor reached 70% left and right sides of rated revolution, capacitor disconnected by switch and power supply.

The utlity model has rational in infrastructure, characteristics such as technology is simple, and is not fragile, the comparable original standard of its efficient improves 10-20%.

Describe its technical solution in detail below in conjunction with the embodiment accompanying drawing:

Fig. 1 is an electrical schematic diagram of the present utility model.

Fig. 2 is the oscillogram of voltage and current.

Fig. 3 (A). (B). (C) be the formation schematic diagram of the two poles of the earth rotating magnetic field respectively.

Fig. 4 is winding connection figure.

Fig. 5 is the winding overhang Pareto diagram.

Fig. 6 is the cut-away view of starter.

The structure of this efficient monopole asynchronous motor includes support, stator core, stator winding, end cap, rotor.Its winding is arranged feature: have only main winding ad in the stator, the place is provided with centre cap c and b in the middle of the main winding ad, and centre cap draws from the top of the end of winding ac and winding bd, and it makes main winding be divided into two sections of ac, bd; (with reference to Fig. 1) winding ac, bd space in stator core slot distributes the adjacent arrangement in top of the top of winding ac and winding bd, the terminal adjacent arrangement of the end of winding ac and winding bd; Centre cap and startup capacitor (C) and starting switch (K ₂) link to each other.The every groove number of turn of winding coil in stator core slot is identical.

Startup principle of the present utility model is as follows: (with reference to Fig. 2, Fig. 3, Fig. 6).

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 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.During 1/8t, the electric current of ac reaches maximum, and the electric current of bd is less than the electric current of ac.Voltage reaches maximum during 1/4t, and the capacitor charging finishes, and the electric current of ac and bd is identical.When forward voltage reduced, capacitor discharged by bd, and 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 among Fig. 3 (A) 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 clockwise 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 (B).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 (C) 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.When 5/8t, magnetic field center is based upon on anodal c and the negative pole a.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, and can produce bigger startup changes distance.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 changes apart from also big more.

Fig. 4 is winding connection figure of the present utility model, and Fig. 5 is a winding overhang Pareto diagram of the present utility model.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 achievement group bd.The head end of winding ac connects power line, end connects the head end of bd, and draws tap herein and connect capacitor.The end of bd connects another power line.

Fig. 6 is the cut-away view of starter.Capacitor and triple-pole switch are housed in the starter.The starter outside is provided with start button and stop button.(not drawing among the figure) K ₂The capacitor of connecting; Back-moving spring is arranged below the start button.Press start 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 loose one's grip, start button is 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 the moving button of openhanded unlatching, 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.

The utility model embodiment, with 4 grades of motors of 60W, mate 235 μ F electrolytic capacitors and test data such as following table:

Pilot project	Test data	Standard-required	Efficient improves	Remarks
Pilot project	Test data	Standard-required	Efficient improves	Remarks	Starting changes distance	2.2 doubly	1.7 doubly
Maximum torque	3.05 doubly	1.8 doubly			Starting changes distance	2.2 doubly	1.7 doubly
Maximum torque	3.05 doubly	1.8 doubly			Starting current	5.2A	9A
Full-load current	1A	1.23A			Starting current	5.2A	9A
Full-load current	1A	1.23A			Temperature rise	42℃	75K
Electric efficiency	42.9％	3.9％	10％		Temperature rise	42℃	75K

As can be seen from the table, the various runnabilities of motor all are up to state standards.The startup of motor is changeed apart from being directly proportional with capacitor volume, can adjust easily to start and change distance.The power bracket of motor is unrestricted, can make the motor of 60W-750W.Because copper factor is low, the sectional area of suitable increasing lead is to improve efficiency of motor under the prerequisite of saving copper cash.

Claims

1 ,-kind of efficient monopole asynchronous motor, include support, stator core, stator winding, end cap, rotor, it is characterized in that: have only main winding (ad) in the stator, the place is provided with centre cap (c) and (b) in the middle of the main winding (ad), centre cap draws from the top of the end of winding (ac) and winding (bd), makes 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 terminal adjacent arrangement of the end of winding (ac) and winding (bd); Centre cap and startup capacitor (C) and starting switch (K ₂) link to each other.

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