Utility model content
(1) technical matters that will solve
The purpose of this utility model is exactly the shortcoming that will overcome prior art:
1) temperature-control circuit is not focused on the shortcoming of switch detection out of control, aims to provide a kind of PTC(positive temperature coefficient (PTC) that strengthens fault-detecting ability) and NTC(negative temperature coefficient) dual control circuit temperature.
2) NTC layer carried metal line burn out detection less than shortcoming, aim to provide a kind of protective device whether metal wire breaks that detects.
(2) technical scheme
For achieving the above object, PTC/NTC dual control temperature control device of the present utility model, comprise controller and heater, its middle controller comprises microprocessor, DC voltage circuit, synchronous signal circuit, gear setting, keypress function selection, reference voltage circuit, indicating circuit, and heater comprises PTC line with heating function, NTC layer, metal wire; Described controller also comprises the first comparer, the second comparer, the 3rd comparer, NTC load detecting, NTC voltage sampling, photoelectric coupled circuit, PTC voltage sampling and ghyristor circuit;
The first comparer: this circuit one end and PTC voltage sampling join, and the other end and reference voltage join, and output terminal and microprocessor join;
The second comparer: this circuit one end and reference voltage join, the other end and NTC voltage sampling join, and output terminal and microprocessor join;
The 3rd comparer: this circuit one end and reference voltage join, the other end and NTC load detecting are joined, and output terminal and microprocessor join;
NTC load detecting: this circuit one end and the 3rd comparer join, and the other end and metal wire join;
NTC voltage sampling: this circuit one end and the second comparer join, and the other end and metal wire join;
Photoelectric coupled circuit: one end and the microprocessor of this circuit control end join, other end ground connection; One termination AC power of controlled terminal, another termination metal wire;
PTC voltage sampling: this circuit one end and the first comparer join, the other end joins with work controllable silicon one end, then one end ground connection;
Ghyristor circuit: this circuit one end and micro-processing are joined, the other end and PTC voltage sampling join, then one end and PTC line with heating function join.
Further, described ghyristor circuit comprises the 4th comparer, DC reference voltage circuit, controllable silicon short-circuit detecting circuit, protection controllable silicon and work controllable silicon, described the 4th comparer and described DC reference voltage circuit and the electrical connection of controllable silicon short-circuit detecting circuit, described protection controllable silicon, described work controllable silicon and the electrical connection of described PTC voltage sample circuit;
Further, described ghyristor circuit comprises controllable silicon short-circuit detecting circuit, the first work controllable silicon and the second work controllable silicon of mutual electrical connection.
Further; described work controllable silicon is a bidirectional triode thyristor; described protection controllable silicon is that the in-phase end of the 4th comparer joins and is connected with described bidirectional triode thyristor with controllable silicon short-circuit detecting described in an one-way SCR, and the end of oppisite phase of described the 4th comparer connects DC reference voltage.
Further, described the first and second work controllable silicons are bidirectional triode thyristor.
Further, described photoelectric coupled circuit can replace with controllable silicon.
(3) beneficial effect
Compared with prior art, the technical solution of the utility model has the following advantages: the disconnection of metal wire can be detected, and controllable silicon positive half-wave and negative half-wave short-circuit conditions be detected, avoid controllable silicon short circuit to cause unnecessary accident.
Embodiment
Below in conjunction with drawings and Examples, embodiment of the present utility model is described in further detail.Following examples are used for illustrating the utility model, but are not used for limiting scope of the present utility model.
Embodiment mono-
As depicted in figs. 1 and 2, PTC/NTC dual control temperature control device of the present utility model, comprise controller and heater 1, its middle controller comprises that microprocessor 2, DC voltage circuit 5, synchronous signal circuit 6, gear arrange 7, keypress function selects 3, reference voltage circuit 8, indicating circuit 4, and heater 1 comprises PTC line with heating function, NTC layer, metal wire; Described controller also comprises the first comparer 9, ` the second comparer 10, the 3rd comparer 12, NTC load detecting 14, NTC voltage sampling 11, photoelectric coupled circuit 13, PTC voltage sampling 18 and ghyristor circuit;
The first comparer 9: this circuit one end and PTC voltage sampling 18 join, the other end and reference voltage circuit 8 join, and output terminal and microprocessor 2 join;
The second comparer 10: this circuit one end and reference voltage circuit 8 join, the other end and NTC voltage sampling 11 join, and output terminal and microprocessor 2 join;
The 3rd comparer 12: this circuit one end and reference voltage circuit 8 join, the other end and NTC load detecting 14 are joined, and output terminal and microprocessor 2 join;
NTC load detecting 14: this circuit one end and the 3rd comparer 12 join, and the other end and metal wire join;
NTC voltage sampling 11: this circuit one end and the second comparer 10 join, and the other end and metal wire join;
Photoelectric coupled circuit 13: one end of this circuit control end and microprocessor 2 join, other end ground connection; One termination AC power of controlled terminal, another termination metal wire;
PTC voltage sampling 18: this circuit one end and the first comparer 9 join, the other end joins with work controllable silicon one end, then one end ground connection;
Ghyristor circuit: this circuit one end and microprocessor 2 join, the other end and PTC voltage sampling 18 join, and the 3rd end and PTC line with heating function join.
Described ghyristor circuit comprises the 4th comparer 17, DC reference voltage 19, controllable silicon short-circuit detecting circuit 16, protection controllable silicon 20 and work controllable silicon 15; described the 4th comparer and described DC reference voltage circuit 19 and 16 electrical connections of controllable silicon short-circuit detecting circuit, described protection controllable silicon 20, described work controllable silicon 15 and 18 electrical connections of described PTC voltage sample circuit.
Described work controllable silicon is a bidirectional triode thyristor; described protection controllable silicon 20 is an one-way SCR; the in-phase input end of described the 4th comparer 17 joins and is connected with described work controllable silicon 15 with controllable silicon short-circuit detecting 16, and the inverting input of described the 4th comparer 17 connects DC reference voltage circuit 19.
Circuit theory of the present utility model as shown in Figure 3.
Fig. 4 is controllable silicon short-circuit detecting process, and in figure, arrow is current direction:
Work controllable silicon 15 upper ends and PTC line with heating function H2 end join, and control end is by capacitor C 7, and resistance R 34 is joined with microprocessor 2, and lower end joins with the 4th comparer 17 in-phase ends by short-circuit detecting circuit 16 again;
Controllable silicon short-circuit detecting circuit 16 upper ends join with work controllable silicon 15 lower ends, and lower end and the 4th comparer 17 in-phase ends join.
The 4th comparer 17 end of oppisite phase and DC reference voltage circuit 19 join; In-phase end and controllable silicon short-circuit detecting circuit 16 join, and output terminal and microprocessor 2 join.
Protection controllable silicon 20 upper ends and AC power AC3 point join, and control end joins by resistance R 41 and microprocessor 2, and lower end and controllable silicon short-circuit detecting 16 are joined.
If during the positive half-wave short circuit that work controllable silicon 15 exchanges; current direction: AC power AC1 → AC3 → work controllable silicon 15 → controllable silicon short-circuit detecting the 16 → four comparer 17; comparative result is to microprocessor 2; microprocessor 2 is just controlled 20 conductings of protection controllable silicon; blow warm fuse; make down circuitry, current direction: AC power AC1 → AC3 → protection controllable silicon 20 → controllable silicon short-circuit detecting circuit 16(resistance R 37) → ground.
This silicon controlled rectifier protecting circuit advantage: like product is without this defencive function on the market; because of the long-term ON/OFF work of bidirectional triode thyristor, the time has been grown likely can be out of control, and product can heat always; until line with heating function burns out; can cause casualties and property loss, based on this problem, this circuit design is after the short circuit of work controllable silicon positive half-wave; microprocessor 2 can detect and control 20 conductings of protection controllable silicon; blowout, makes down circuitry, reaches security purpose.
As shown in Figure 8, arrow is current direction to the testing process of metal wire:
First optocoupler control end one termination microprocessor 2, other end ground connection; Controlled terminal one termination AC power, another termination metal wire upper end (H3); PTC line with heating function one end (H1) connects AC power, and the other end (H2) meets work controllable silicon T1; Metal wire one termination optocoupler controlled terminal (optocoupler unlatching controlled terminal and reference voltage circuit 8 are synchronous), the other end (H4) connects the 3rd comparer 12 negative phase ends by NTC load detecting 14; Microprocessor 2 triggers work controllable silicon to optocoupler control end voltage (as Fig. 7), current direction: microprocessor 2 → optocoupler is controlled upper end → ground, controlled terminal conducting (as Fig. 7) current direction: the end of oppisite phase of AC power → optocoupler controlled terminal → metal wire → NTC load detecting the 14 → three comparer 12 and the reference voltage circuit of the 3rd comparer 12 in-phase ends 8 are relatively, comparative result outputs to microprocessor 2, low level judgement metal wire is normal, and high level judgement metal wire disconnects.Microprocessor 2 is turned off work controllable silicon, and PTC line with heating function does not heat, fault prompting.
Photoelectric coupled circuit 13 can replace with controllable silicon.
The advantage of this circuit: on the market like product when NTC carried metal line inner any one or many places disconnection detection less than, can cause heater 1 excess Temperature, and then burn out line with heating function, the personnel that cause burn or property loss.This circuit can detect and control heater 1 and do not generate heat, simultaneous faults prompting when NTC carried metal line inner any one or many places disconnect microprocessor 2; Improved the design drawback of like product on the market.
Embodiment bis-
As shown in Figure 5, the present embodiment and embodiment mono-are basic identical, consult Fig. 6 schematic diagram, difference is, ghyristor circuit comprises that controllable silicon short-circuit detecting 16, the first work controllable silicon 15 and the second work controllable silicon 17 form, and the first work controllable silicon 15 and the second work controllable silicon 17 are bidirectional triode thyristor, as shown in Figure 7, in figure, arrow is current direction to its short-circuit detecting process:
Work controllable silicon 15 upper ends and PTC line with heating function H2 end join and join with controllable silicon short-circuit detecting circuit 16 simultaneously; Control end is by capacitor C 7, and resistance R 34 is joined with microprocessor 2; Lower end joins and joins with controllable silicon short-circuit detecting circuit 16 with work controllable silicon 17 upper ends simultaneously.
Work controllable silicon 17 upper ends join and join with controllable silicon short-circuit detecting 16 with work controllable silicon 15 lower ends simultaneously; Control end is by capacitor C 8, and resistance R 41 is joined with microprocessor 2, and lower end and PTC voltage sample circuit 18 join;
Controllable silicon short circuit inspection circuit 16 upper ends join with work controllable silicon 15 upper ends and PTC line with heating function lower end H2, and test side and microprocessor 2 join, lower end ground connection.
(current direction: ground → controllable silicon short-circuit detecting circuit 16 → work controllable silicon 15 → PTC line with heating function → AC power AC1) when the negative half-wave short circuit of work controllable silicon 15, controllable silicon short-circuit detecting circuit 16 is detected to 16 voltages to microprocessor 2 phase contacts and drag down level, microprocessor 2 detects rear output low level to two work SCR control utmost points, make the cut-off of work controllable silicon, main body does not heat, simultaneous faults prompting.
(current direction: AC power AC1 → PTC line with heating function → controllable silicon short-circuit detecting circuit 16 → work controllable silicon 17 → PTC voltage sampling 18(R37) → ground when the 17 positive half-wave short circuit of work controllable silicon), controllable silicon short-circuit detecting circuit 16 and microprocessor 2 point voltage that joins is dragged down, microprocessor 2 detects rear output low level to two work SCR control utmost points, 15 cut-offs of work controllable silicon, main body does not heat, simultaneous faults prompting.
This silicon controlled rectifier protecting circuit advantage: like product is without this defencive function on the market, because of the long-term ON/OFF work of bidirectional triode thyristor, time has been grown likely can be out of control, and product can heat always, until line with heating function burns out, can cause casualties and property loss, based on this problem, two bidirectional triode thyristor series connection of this circuit design, after the negative half-wave short circuit of work controllable silicon 15, microprocessor 2 is controlled 17 cut-offs of work controllable silicon, and heater 1 does not generate heat; After the 17 positive half-wave short circuits of work controllable silicon, microprocessor 2 is controlled 15 cut-offs of work controllable silicon, and heater 1 does not generate heat; Even if two silicon controlleds exchange positive and negative half-wave and open circuit simultaneously, microprocessor 2 detects fault prompting too, reaches security purpose.
In sum, above-mentioned embodiment is not restricted embodiment of the present utility model, and the modification that all those skilled in the art carry out on the basis of flesh and blood of the present utility model or equivalent deformation, all at technology category of the present utility model.