CN2218985Y - Phase-loss, over-load protector for motor - Google Patents

Abstract

The utility model relates to a phase-loss and over-load protector for motors, which is composed of an overcurrent sampling circuit, a pulse forming circuit, an or gate circuit, a clamping circuit, a controlling circuit, a time delay executive circuit, an indication circuit and a power supply circuit. The utility model has the working principle that the sampling circuit and the normal power supply circuit are compared. When the current is normal, the motor is normally operated, and the sampling circuit does not work. When the current is enlarged, the sampling circuit works, and the power supply circuit is cut off, so the purpose of protecting motors is obtained.

Description

The motor phase failure, overload protective device

The utility model relates to a kind of motor phase failure, overload protective device that is used to protect motor.

Some motor protecter of current use, complex structure, cost height, function are poor, often can not play the effect of protection motor.

The purpose of this utility model is exactly that a kind of motor phase failure, overload protective device are provided in order to overcome the deficiencies in the prior art.

The purpose of this utility model can reach by following measure:

This protector is made up of overcurrent sample circuit, pulse shaping circuit, OR circuit, clamp circuit, control circuit, delay executing circuit, indicating circuit and power-supply circuit.Concrete operating circuit is, three power supply A, B, C series connection mutual inductor Q ₁, Q ₂, Q ₃After normal opened contact J ₂Insert motor D.C item power supply is through normally closed knob AN ₁Often open knob AN ₂After meet transformer B respectively ₁One end and the relay J of primary coil ₂One end of coil.AN ₂With normal opened contact J ₁In parallel.B ₁The elementary other end is connected on coil Q ₂Elementary and contact J ₂Between, relay J ₂The other end of coil is connected on coil Q ₁Elementary and contact J ₂Between.B ₁Secondary through bridge rectifier D ₉Back positive pole meets capacitor C ₃Positive pole, negative pole meets C ₃Negative pole, C ₃With transistor BG ₂Parallel connection, C ₃Positive pole and BG ₂Connect relay J between the collector electrode ₁Coil, C ₃Negative pole and BG ₂Connect light-emitting diode D between the emitter ₈Negative pole.BG ₂Base stage through resistance R ₄, potentiometer W ₂After contact J ₃One end, contact J ₃With capacitor C ₂Parallel connection, C ₂Positive pole meets D ₉Positive pole, C ₂Negative pole meets W ₂Contact J ₃The other end is through relay J ₃Meet transistor BG ₁Collector electrode, BG ₁Emitter meet D ₉Negative pole.Q ₃The secondary series connection diode of coil D ₁, shunt capacitor C ₁, D ₁Negative pole and C ₁Anodal connection, resistance R ₁Series connection light-emitting diode D ₂Back and C ₁Parallel connection, D ₂Negative pole meets C ₁Negative pole.Potentiometer W ₁With R ₁And C ₁The series circuit parallel connection, W ₁With R ₁Between connect diode D ₃(or door), D ₃Negative pole meet W ₁W ₁Point of adjustment through voltage stabilizing didoe D ₆Positive pole and resistance R ₂After meet D ₉Negative pole.BG ₁Base stage pass through resistance R ₃Be connected on D ₆With R ₂Between, voltage stabilizing didoe D ₇Negative pole meet D ₉Negative pole, its positive pole meets BG ₁The utmost point, D ₉Negative pole meets D ₂Negative pole.

The purpose of this utility model can also reach by following measure:

Q ₁Coil, Q ₂The operating circuit of coil and Q ₃Operating circuit is identical.Q wherein ₁Use diode D in the circuit ₅(or door), and Q ₂Use diode D in the circuit ₄(or door).

The explanation of accompanying drawing drawing:

Fig. 1 is a block diagram of the present utility model.

Fig. 2 is the physical circuit figure of Fig. 1.

The utlity model has following advantage:

1, highly sensitive.

2, wide accommodation.

3, has delay function.

4, sphere of action is wide.

Below the utility model is further described:

As shown in the figure, its course of work and overcurrent protection principle are as follows: when opening motor, press start button AN ₂, treat to unclamp AN again after motor runs well ₂When pressing AN ₂After, C phase power supply is through AN ₁→ ANN ₂→ power transformer B ₁→ B constitutes the loop mutually.B ₁Energising work, its secondary output AC electricity is through D ₉Rectification, C ₃After the filtering, through J ₁, J ₃Be added to BG ₁, BG ₂Collector electrode is at BG ₂Base stage and BG ₁C is arranged between the collector electrode ₂, W ₂, R ₄The delay circuit of forming.C ₂Be delay capacitor, W ₂With R ₄Series connection is as BG ₂Base biasing resistor, simultaneously the double as delay time is regulated.Because BG ₁With BG ₂Be connected into inverter, and BG ₁Base stage is a zero potential when initial condition, so BG ₁End BG ₂Logical, J ₁Adhesive, its normally opened contact makes AN ₂Realize self-locking.Meanwhile, C order power supply is by AN ₁→ AN ₂→ J ₂→ A phase power supply constitutes another path, makes J ₂Adhesive, the closing of contact is connected motor power, enters starting state.With C is example mutually, when bigger starting current passes through Q ₃Primary winding the time, on its secondary coil, just induce an alternating voltage, send into pulse shaping circuit.By D ₁, C ₁The pulse shaping circuit of forming becomes dc pulse signal with the AC voltage conversion of taking a sample.This signal at first is added in by R ₁, D ₂The indicating circuit of forming uses D ₂Send stronger ruddiness, expression is in starting state.Another road is added in the diode D of OR circuit simultaneously ₃Positive pole, door is opened, through W ₁After the adjustment, be added to by D ₆, R ₂The clamping diode D of the first order clamp circuit of forming ₇Anodal.Because current of electric is big, so pulse signal voltage is also high, makes D ₆Puncture conducting, pulse signal is through D ₃Deliver to BG ₁Base stage.BG ₁Conducting, J ₃Adhesive, and at C ₂The J at two ends ₃Often closing the contact disconnects.At this moment, power supply is through BG ₂Base stage, R ₄, W ₂To C ₂Charging, its charging interval promptly is that setting-up time is carried out in time-delay.Because this charging current flows through BG ₂So base stage is BG ₂Can continue to keep conducting, drop to gradually up to charging current and can not keep BG ₂During conducting, BG ₂Just end J ₁Discharge, cut off motor power.When quitting work, click AN ₁Get final product.

In Fig. 2, only the drawn circuit diagram of C item power supply because the circuit diagram of A, B item power supply is identical with the C item, the Therefore, omited it.

Claims (2)

1, a kind of motor phase failure, overload protective device; form by overcurrent sample circuit, pulse shaping circuit, OR circuit, clamp circuit, control circuit, delay executing circuit, indicating circuit and power-supply circuit, it is characterized in that: three power supply A, B, C series connection mutual inductor Q ₁, Q ₂, Q ₃After normal opened contact J ₂Insert motor D, C item power supply is through normally closed knob AN ₁Often open knob AN ₂After meet transformer B respectively ₁One end and the relay J of primary coil ₂One end of coil, AN ₂With normal opened contact J ₁Parallel connection, B ₁The elementary other end is connected on coil Q ₂Elementary and contact J ₂Between, relay J ₂The other end of coil is connected on coil Q ₁Elementary and contact J ₂Between, B ₁Secondary through bridge rectifier D ₉Back positive pole meets capacitor C ₃Positive pole, negative pole meets C ₃Negative pole, C ₃With transistor BG ₂Parallel connection, C ₃Positive pole and BG ₂Connect relay J between the collector electrode ₁Coil, C ₃Negative pole and BG ₂Connect light-emitting diode D between the emitter ₈Negative pole, BG ₂Base stage through resistance R ₄, potentiometer W ₂After contact J ₃One end, contact J ₃With capacitor C ₂Parallel connection, C ₂Positive pole meets D ₉Positive pole, C ₂Negative pole meets W ₂, contact J ₃The other end is through relay J ₃Meet transistor BG ₁Collector electrode, BG ₁Emitter meet D ₉Negative pole;

Q ₃The secondary series connection diode of coil D ₁, shunt capacitor C ₁, D ₁Negative pole and C ₁Anodal connection, resistance R ₁Series connection light-emitting diode D ₂Back and C ₁Parallel connection, D ₂Negative pole meets C ₁Negative pole, potentiometer W ₁With R ₁And C ₁The series circuit parallel connection, W ₁With R ₁Between connect diode D ₃(or door), D ₃Negative pole meet W ₁, W ₁Point of adjustment through voltage stabilizing didoe D ₆Positive pole and resistance R ₂After meet D ₂Negative pole, BG ₁Base stage pass through resistance R ₃Be connected on D ₆With R ₂Between, voltage stabilizing didoe D ₇Negative pole meet D ₉Negative pole, its positive pole meets BG ₁Base stage, D ₉Negative pole meets D ₂Negative pole.

2, according to the said motor phase failure of claim 1, overload protective device, it is characterized in that: Q ₁Coil, Q ₂The operating circuit of coil and Q ₃Operating circuit is identical, wherein Q ₁Use diode D in the circuit ₅(or door), and Q ₂Use diode D in the circuit ₄(or door).

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