CN2676058Y

CN2676058Y - Flame detection device

Info

Publication number: CN2676058Y
Application number: CN 200320122505
Authority: CN
Inventors: 毛敏; 陈云飞
Original assignee: East China Normal University
Current assignee: East China Normal University
Priority date: 2003-12-16
Filing date: 2003-12-16
Publication date: 2005-02-02
Anticipated expiration: 2013-12-16

Abstract

A flame detecting device belongs to the field of electronic control and sensor technology. The flame detecting device mainly comprises a burner (21), an ignition detecting needle (22), conducting wires (23), an ignition detecting controller (24) and a pedestal (25). Since it just uses an ignition detecting needle which has two functions of the high voltage pulse ignition and the low voltage impulse flame detecting, the flame detecting device can be applied to the installation in the smaller space, and it has considerable effects such as simple structure, good sensibility, and low cost, etc. In addition, the flame detecting device also has good application future on the domestic gas apparatus.

Description

Flame detecting device

Technical field

The utility model relates to a kind of flame detecting device, uses flame detecting device on especially a kind of suitable gas kitchen ranges, gas heater and other combustion gas tools, belongs to Electronic Control and sensor technical field.

Background technology

Flame detecting device has some kinds, as optical pickocff, and mechanical pick-up device, the common complex structure of this class sensor, cost is also higher.Also have a kind of temperature sensor, thermocouple for example, though cost is relatively low, in igniting with when flame-out, the foundation of thermoelectrical potential and disappear all arranged certain lag time, thus increased the complexity of control circuit, cause the totle drilling cost of relative assembly to increase.In addition, inventor Chen Yun flies in Chinese patent " the flame monitor " (patent No.: disclose ZL94239042.3) and a kind ofly formed flame detector by two metal electrodes.This flame detector places two electrodes among the flame of burner.Flame makes two air generation ionization between the electrode, produces more weak electromotive force, in case the fray-out of flame electromotive force disappears immediately, if should be faint after electromotive force amplifies, can report to the police or light a fire again by difference requirements when flame produce or extinguishes.This device has simple in structure, highly sensitive, respond advantages such as fast, its weak point is: what this flame monitor adopted is two probes, common one is flame detection pin, one is the igniting spray point, because flame detects between pin and the igniting spray point probe certain mounting distance must be arranged, otherwise the igniting spray point can detect needle-discharging to flame, influence the circuit operate as normal, therefore the installation of these several pins is more loaded down with trivial details, and in some specific occasions, in the vehicular water heater, in order to dwindle the space, the burner side does not allow to install two pins, and secondly, the material of flame pin is a kind of infusibility metal or alloy material.

The utility model content

That the purpose of this utility model is to provide is a kind of single needle, highly sensitive, fast and the low flame detecting device of cost to simplify flame detecting device, solves the problem at less space mounting flame detecting device.

Flame detecting device of the present utility model comprises that burner 21, igniting detect pin 22, lead 23, igniting detection controller 24 and base 25, it is characterized in that described igniting detects pin 22 and has only one.

Igniting described in the flame detecting device of the present utility model detects controller 24 and comprises that microcontroller 1, firing circuit 2, buffer circuit 3, solenoid valve control circuit 4, flame detection circuit 5, igniting detect pin 22, it is characterized in that also comprising buffer circuit (3), this buffer circuit (3) is made up of two diodes, two diode cathodes are cascaded relatively, and anode is connected to two outputs of microcontroller.

Flame detecting device of the present utility model, because only adopted an igniting to detect pin, and this root igniting detected pin compatibility high-voltage pulse igniting and two kinds of functions of action of low-voltage pulse flame detection, realize that by microcontroller and buffer circuit firing pulse oscillator and flame detect the shared of oscillator, therefore can realize that single needle reaches automatic igniting, accident extinguishing closes functions such as gas check valve and warning automatically, compare with in the past the crosspointer or the flame detector of spininess, have and be adapted at less space mounting flame detecting device, simple in structure, the low remarkable result that waits of highly sensitive and cost.

Description of drawings

Fig. 1 is the flame detecting device structure chart

Fig. 2 is that the igniting of flame detecting device detects the controller structural map

Fig. 3 is that the igniting of flame detecting device detects the microcontroller circuit figure in the controller

The specific embodiment

Below in conjunction with Figure of description the specific embodiment of the present utility model is described:

Igniting detection controller 24 is fixed on the base 25 in the flame detecting device structure chart of the present utility model, igniting detects pin 22 and detects controller 24 controls by igniting, fuel gas is sent by burner 21, and igniting detects pin 22 and is connected by lead 23 and igniting detection controller 24 lines.

The fire of flame detecting device detects the controller structural map and comprises microcontroller 1, is the control core of system; Firing circuit 2 comprises oscillator, step-up transformer and high voltage package; Buffer circuit 3; Solenoid valve control circuit 4; Flame detection circuit 5; Igniting detects pin 22, and it is installed near the burner, has the function of igniting, flame detection concurrently.

A point in Fig. 3 is a buffer circuit 3 to the B point, and by Z1, Z2 forms, and the flame sense channel is C1, C2, and D1, D2, and R1 also have the software among the MCU, and P1 is that igniting detects pin 22; B1 is a high voltage package, B2 and Q1, and R5, R6 constitutes the inductance Coplitts oscillator, and to keep the part vibration, MCU is by Q2 and R8, and D4 opens or closed portion vibrates to realize that public one is detected pin, and other parts are the conventional criteria circuit substantially, this paper describes in detail no longer one by one.

When opening the tap of water heater or during the burner switch, controller power source is connected, igniting detects pin 22 and detects less than flame because of no fuel gas buring, about voltage of 200 millivolts of flame detection circuit 5 outputs is to microcontroller 1, microcontroller 1 is through after the computing relatively, send instruction unpack firing circuit 2, after passing through the oscillation transformer inversion boosting then, produce firing pulse, boost once more through the igniting high voltage package, export about 15 kilovolts high-voltage pulse and deliver to igniting detection pin 22, igniting detects pin 22 output high-voltage arcs burner is discharged, after 1 second, microcontroller is opened solenoid valve control circuit 5, fuel gas runs into high-voltage arc and promptly burns on burner, the igniting of burning back detects pin 22 and detects faint flame ion conduction immediately, the signal of negative 200 millivolts of flame detection circuit 5 outputs is to microcontroller 1, after microcontroller 1 detects this signal, learn that flame burns, wait for 500 milliseconds, treat flame stabilization after, microcontroller 1 i.e. part cuts out oscillator, step-up transformer and high voltage package quit work thus, and igniting detects pin 22 and stops arc discharge, and burner enters normal operating condition.

Above-mentioned part is closed oscillator and is meant under the coordination control of microcontroller 1, and the detection of the discharge pulse of high-power and low pressure Weak current is able to finish on same igniting detection pin.During power supply opening, vibration a little less than having one on the oscillator 2, this weak vibration is delivered to igniting by voltage-stabiliser tube buffer circuit 3 and detects pin 22, always in flame detection, when microcontroller 1 sends firing command, starting of oscillation work, through boosting the secondary inversion, igniting detects on the pin 22 ignition arc promptly takes place, and igniting at this moment detects on the pin 22 and has two signals simultaneously, the high-voltage pulse of tens thousand of volts and several millivolts of low-voltage signals that flame detects, microcontroller 1 flame detection not when ignition arc occurs, do not do other processing yet, be in resting state, in order to avoid powerful electromagnetic pulse interference flame detects; Behind arc ending, microcontroller 1 starts rapidly, and part is closed oscillator, and by flame sense channel flame detection with carry out other work, these work are generally finished in less than 1 millisecond, and microcontroller 1 is opened oscillator immediately subsequently, waits for electric arc next time.So the signal that two amplitudes differ greatly has perfectly focused on the same draw point through the time-division processing of voltage-stabiliser tube buffer circuit 3 and microcontroller 1.

If flame-out suddenly when normal combustion, will cause danger such as combustion gas leakage, the utility model is taked methods of printing in limited time, be that MCU detects less than flame igniting again immediately, as in setting-up time, not lighting, then close gas electromagnetic valve, notify the user with display devices such as light emitting diodes.

If the too high or supply voltage of water temperature occurs when normal combustion not in normal range (NR), microcontroller can both take measures to cut out magnetic valve to guarantee safety.

Flame detecting device described in the utility model not only is fit to, have broad application prospects on other combustion gas tools such as family expenses gas kitchen ranges, gas heater as installing and using in the medium less space of vehicular water heater.

Claims

1, a kind of flame detecting device comprises that burner (21), igniting detect pin (22), lead (23), igniting detection controller (24) and base (25), it is characterized in that described igniting detects pin (22) and has only one.

2, flame detecting device as claimed in claim 1, wherein igniting detection controller (24) comprises that microcontroller (1), firing circuit (2), solenoid valve control circuit (4), flame detection circuit (5), igniting detect pin (22), it is characterized in that also comprising buffer circuit (3), this buffer circuit (3) is made up of two diodes, two diode cathodes are cascaded relatively, and anode is connected to two outputs of microcontroller.