CN2244783Y - Automatic detecting protector for input under-voltage or overvoltage of computerized oil feeder - Google Patents

Abstract

The utility model relates to a computer oil adding machine protecting device and is provided with an alternate current power supply connecting port, a rectifying wave filtering circuit, a sampling circuit, an upper limit voltage reference circuit, an upper limit voltage comparing device, a lower limit voltage reference circuit, a lower limit voltage comparing device, an and circuit, a controlling switch and a load connecting port. The input ends of the upper and lower limit voltage comparing devices are connected with the sampling circuit, and the other input ends of the upper and lower limit voltage comparing devices are respectively connected with the upper and lower limit voltage reference circuits. The output ends of the upper and lower limit voltage comparing devices are respectively connected with the two input ends of the and circuit, and the controlling switch is arranged between the alternate current power supply connecting port and the load connecting port. The output end of the and circuit is connected with the controlling end of the controlling switch.

Description

Computer fuel charger is imported under-voltage overvoltage and is detected protector automatically

The utility model relates to a kind of power protector, and especially a kind of under-voltage overvoltage of input that is used for computer fuel charger detects protector automatically.

Along with the application of computer technology, computer fuel charger is accepted by people gradually, but because the computer that power network fluctuation or gas station generate electricity voluntarily to fuel charger brings harmful effect, when serious even burn out machine.In order to make the computer fuel charger can operate as normal, be necessary it is implemented protection.China's utility application 87206118 discloses a kind of full-automatic electricity-saving protection device; this protector is differentiated control circuit and is protected delayed recovery circuit to form by current sample input circuit, current buffering delay circuit, electric current; in the time of can being implemented in overcurrent electrical appliance is protected; but this protector is the same with existing various protector, and is not suitable for computer fuel charger.For this reason, be necessary to provide a kind of protector that is exclusively used in computer fuel charger.

The purpose of this utility model promptly provides a kind ofly can be when under-voltage and overvoltage condition implements the automatic detection protector protected to computer fuel charger automatically.

Computer fuel charger of the present utility model is imported under-voltage overvoltage and is detected protector automatically and have AC power interface, control switch and loading interfaces, and is provided with current rectifying and wave filtering circuit, sample circuit, upper voltage limit reference circuit, upper voltage limit comparator, lower voltage limit reference circuit, lower voltage limit comparator and AND circuit especially.In the utility model, the sample circuit that is provided with is taken a sample to external voltage from AC power interface, the sampled signal that obtains puts on the input of upper voltage limit comparator and lower voltage limit comparator, because the input of upper and lower limit voltage comparator also joins with the upper and lower limit voltage reference circuit respectively, thereby can compare external voltage.In case external voltage overrate; the upper limit or lower voltage limit comparator promptly send signal to AND circuit; the corresponding signal that sends of AND circuit makes the control switch action, cuts off the path between AC power interface and the loading interfaces, to implementing protection by the computer fuel charger of loading interfaces power supply.When external voltage recovers just often, control switch resets, and computer fuel charger is operate as normal again.

Computer fuel charger of the present utility model is imported under-voltage overvoltage and is detected protector automatically and compare with aforementioned existing protector, can realize the under-voltage and overvoltage protection to computer fuel charger, protects computer effectively, prolongs the useful life of computer.

Content of the present utility model further illustrates with the following Examples, but content of the present utility model is not limited only to content related among the embodiment.

Fig. 1 is that computer fuel charger is imported the circuit block diagram that under-voltage overvoltage detects protector automatically among the embodiment.

Fig. 2 is a circuit diagram.

As shown in Figure 1; computer fuel charger among the embodiment is imported under-voltage overvoltage and is detected protector automatically and have AC power interface 1, control switch 9 and loading interfaces 10, and has current rectifying and wave filtering circuit 2, sample circuit 3, upper voltage limit reference circuit 4, upper voltage limit comparator 5, lower voltage limit reference circuit 6, lower voltage limit comparator 7 and AND circuit 8 especially.AC power interface 1 links to each other with the input of sample circuit 3 and the input of current rectifying and wave filtering circuit 2, one input of upper voltage limit comparator 5 and an input of lower voltage limit comparator 7 are with the output that accesses sample circuit 3, another input of upper voltage limit comparator 5 connects to ration the power supply presses reference circuit 4, another input termination lower voltage limit reference circuit 6 of lower voltage limit comparator 7, the output of the output of upper voltage limit comparator 5 and lower voltage limit comparator 7 connects two inputs of AND circuit 8 respectively, control switch 9 is arranged between AC power interface 1 and the loading interfaces 10, the control end of the output termination control switch 9 of AND circuit 8.

As shown in Figure 2, the AC power interface in the circuit block diagram 1 is contact a, b; Loading interfaces 10 is contact c, d; Current rectifying and wave filtering circuit 2 is made of D3, C1 and R4; Sample circuit 3 is made of R2, R3, C2, C3; Upper voltage limit reference circuit 4 is made of R8, R9; Upper voltage limit comparator 5 is U3; Lower voltage limit reference circuit 6 is made of R5, R6; Lower voltage limit comparator 7 is U2.In addition, AND circuit 8 in the present embodiment is made of triode T1 and T2, the base stage of triode T1 and T2 constitutes two inputs of AND circuit respectively, the emitter of triode T1 links to each other with the collector electrode of triode T2, the emitter of triode T2 connects the earth, and the collector electrode of triode T1 constitutes the output of AND circuit; Control switch 9 is made of SP2110 type solid-state relay U1, this solid-state relay has anode, negative terminal exchanges link with two, the high potential output VCC of the positive termination current rectifying and wave filtering circuit of solid-state relay, the negative terminal of solid-state relay constitutes the control end of control switch, and two of solid-state relay exchanges link and connects the b end of AC power interface and the c end of loading interfaces respectively.Also set up the diode D1 and the D2 that are used to suppress the external high pressure disturbing pulse in the present embodiment, certainly, this D1 and D2 also can not be provided with.

When the computer fuel charger in using present embodiment is imported under-voltage overvoltage and detected protector automatically, the loading interfaces of computer power joint and protector can be joined.220 volts of voltages by the AC power interface input pass through D3 rectification, C1 filtering, obtain sampled voltage between R2, R3.After R4 step-down, current limliting, on D4, obtain stable 5V direct voltage, as a comparison the operating voltage of device by filtered direct voltage.Simultaneously, this direct voltage is respectively the reference voltage that R5, R6 and R8, R9 dividing potential drop become comparator U3, U2.Comparator U3, U2 at any time and the sampled voltage between R2, the R3 compare; when input voltage is higher than 260V or be lower than 170 volts; comparator is with output low level; T1 or T2 are ended; the corresponding shutoff of solid-state relay U1; loading interfaces place outage, computer fuel charger is protected, not reason overvoltage or under-voltage and damage.When input voltage returns to normal range (NR), the automatic energized of U1, computer promptly recovers operate as normal.

The SP2110 type solid-state relay U1 that is adopted in the present embodiment also can be replaced by other similar solid-state relay (as JGX series) or controllable silicon, electromagnetic relay, comparator U2, U3 also can adopt other comparator of LM or LF series, also can be by MC, CD series and door integrated circuit or other equivalence or door and NOR gate circuit replacement by the AND circuit that T1, T2 constitute.

Claims (3)

1; a kind of computer fuel charger is imported under-voltage overvoltage and is detected protector automatically; has AC power interface; control switch and loading interfaces; it is characterized in that having current rectifying and wave filtering circuit; sample circuit; the upper voltage limit reference circuit; the upper voltage limit comparator; the lower voltage limit reference circuit; lower voltage limit comparator and AND circuit; described AC power interface links to each other with the input of sample circuit and the input of current rectifying and wave filtering circuit; one input of upper voltage limit comparator and an input of lower voltage limit comparator are with the output that accesses the sample circuit; another input of upper voltage limit comparator connects the pressure reference circuit of rationing the power supply; another input termination lower voltage limit reference circuit of lower voltage limit comparator; the output of the output of upper voltage limit comparator and lower voltage limit comparator connects two inputs of AND circuit respectively; control switch is arranged between AC power interface and the loading interfaces, the control end of the output termination control switch of AND circuit.

2, protector as claimed in claim 1; it is characterized in that described AND circuit is made of triode T1 and T2; the base stage of triode T1 and T2 constitutes two inputs of AND circuit respectively; the emitter of triode T1 links to each other with the collector electrode of triode T2; the emitter of triode T2 connects the earth, and the collector electrode of triode T1 constitutes the output of AND circuit.

3, protector as claimed in claim 1 or 2; it is characterized in that described control switch is made of SP2110 type solid-state relay U1; this solid-state relay has anode, negative terminal exchanges link with two; the high potential output of the described current rectifying and wave filtering circuit of positive termination of solid-state relay; the negative terminal of solid-state relay constitutes the control end of control switch, and two of solid-state relay exchanges link and connects described AC power interface and loading interfaces respectively.

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