JPS6064127A - Automatic ignition and combustion detector in gas combustion apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to ignition devices in gas combustion devices, and more particularly to automatic ignition and combustion detection devices for such devices.

In many devices that burn gas, such as boilers, clothes dryers, ovens, etc., heat is added to the gas ejected from the main burner to ignite it. At this time, gas for 13 burners is generally supplied near a pilot burner that burns continuously to ignite the main burner.

i! l! When the flame of the pilot burner that continues to burn or insufficient combustion is detected, the resistor
There is an automatic ignition device that heats the burner and ignites the burner instead of the pilot burner's flame.

In such a device, the use of charcoal and arsenic (the resistivity of silicon carbide decreases as the temperature rises), which has a negative resistance-temperature characteristic, is used as an ignition device, as disclosed in the U.S. patent as a well-known technique by Kaware Nire et al. There are 3,282,324 gin. This U.S. patent uses a solenoid-operated valve t, and
Connect this solenoid to the ignition element circuit. Since silicon carbide has a negative resistance-temperature property t'1', when heating is required, the current flowing through the igniter increases as the resistance of the igniter decreases. This increases the circuit current formed with the solenoid winding sufficiently to energize the solenoid and open the gas valve.

This device is equipped with a gas valve to close the gas valve in the event of a misfire.
A circuit is provided to invite the ignition system after the ignition is opened.

This ignition element further acts as a heat detection element, and the ignition element r
The gas valve is closed when the current to - drops below a value at which it is confirmed that the flame is extinguished.

The aforementioned US patent constitutes two modes of ignition and heat detection based on the assumption that the current flowing through the ignition element and its resistance value can be ascertained from the temperature of the ignition element. The above assumption ignores the reality that the resistance-temperature characteristics of each arsenic ignition element f- are different. That is, one ignition element exhibits one temperature at a certain resistance value. Then, other ignition elements with the same resistance may exhibit completely different temperatures.Therefore, it is only necessary to set the resistance value of the ignition element f so that it corresponds to a temperature sufficient to ignite the scum. This results in a potentially less accurate device.Furthermore, the time required to open and close the cusp described in this patent is relatively slow.

In U.S. Pat. No. 3,784,351, the ignition element is sufficiently heated via a burner. A radiation detector containing a metal element is placed in the vicinity of the igniter to identify when the igniter has reached the ignition temperature. . When the igniter is activated, the igniter is heated by the current flowing through it until the transition temperature of the bimetallic element r- is reached. The ignition sequence is then initiated when the bimetallic element moves from one contact to the other, supplying gas from the burner and igniting it. Thus, this patent uses a bimetallic element to detect the temperature of the ignition element and to initiate a sequence for ignition when the bimetallic element reaches a predetermined transition temperature.

The present invention provides an improved automatic ignition system for gas-fired appliances such as boilers, clothes dryers, stoves, etc. The present invention ignites gas from near the burner with a variable resistance ignition element.

The device of the present invention includes a means for repeatedly measuring the resistance value of the ignition means and comparing the measured values, and a means for opening the ignition means. When the detection means detects that a certain temperature has been reached, the gas valve is energized and opened.

In one preferred embodiment, extinguishment detection means are provided and a drop in gas pressure is detected. Additionally, visual means indicate the operating status of the device, device failures, etc.

In this way, the device of the present invention uses a resistance-type ignition element, and determines that the ignition element f has reached a temperature sufficient to ignite the gas, even if the temperature characteristics of this ignition element are different. have the ability to Preferably, this function is accomplished using a microcomputer device operating in conjunction with the ignition element. This microcomputer device is programmed to repeatedly measure the resistance value of the ignition element f- at predetermined time intervals and compare the values one after another. In this manner, the microcomputer identifies when the ignition element has reached a flat region exhibiting a resistance-temperature characteristic that is sufficiently hot to ignite the gas.

That is, the microcomputer has two separate jt
From the 11111 value, it is determined that the resistance-temperature characteristic of the ignition element r- has become flat.

In a first process, described below as a warm test, a threshold value is first set as a criterion for the resistance idi of the ignition element f- prior to energizing the ignition element. Then igniter r
-After being energized, the microcomputer measures the resistance value of the ignition element again after a predetermined time 6. If the new measured value is less than the threshold value, the warm test is passed. This shows that the temperature characteristic of the ignition element is in a relatively steep region, and the resistance value decreases relatively rapidly with temperature LS). If the warm test does not fail, the microcomputer measures the resistance of the ignition element f after a predetermined period of time to compare it with a threshold value. This continues until the predetermined time elapses. When a predetermined time has elapsed, the system enters a fault mode, which will be described later.

In the second process described as a hot test,
The Rirocomputer continuously takes measurements and continues this operation until the difference between the successively measured values reaches a predetermined maximum value lead. The ignition element is sufficiently heated in the flat region of the temperature characteristic where the change in resistance Mt++i as the temperature F rises is relatively gradual, and as mentioned above, the gas can be ignited. .

When it is confirmed that the temperature of the ignition element has reached the ignition temperature, a gas valve is opened by a program in the microcomputer, and the gas passes through a burner near the ignition element and is ignited. The ignition element T is then deenergized.

In the preferred device, the microcomputer is programmed to detect extinguishment. This is accomplished by continuously measuring and comparing the resistance values of the ignition elements. Specifically, in the flame detection mode, the microcomputer is programmed to perform two different processes and the canine processes independently have the ability to detect extinguishment. The threshold value of the resistance value is determined below based on the field value or the resistance value of the level ignition element. After ignition, when ignition Jf- is deenergized, the microcomputer continuously monitors the resistance of the ignition element at regular time intervals. Extinction is detected when the resistance of the ignition element exceeds a threshold value, indicating that the plateau area of the ignition element is insufficient to maintain the temperature of the ignition element and the operating point of the ignition element r-.

In a second process, hereinafter referred to as a late test, the microcomputer compares the continuously measured resistances (d4) to determine whether the rate of change in the resistance value of the ignition element exceeds a predetermined value. This predetermined value is selected such that extinguishing of the flame is confirmed. When extinguishing the flame, the microcomputer is preferably programmed to carry out the return operation.

Includes a means to confirm that the value is greater than or equal to the value. For this purpose, the device is preferably equipped with two independently operable gas valves in series. One side communicates with the gas flow between the valves, and the other side is provided with electrically conductive members spaced apart from the contacts and slidable within the conduit section. When the gas valve t on the input side of the conduit section is opened,
As the scum flows into the conduit section, when there is sufficient scum pressure, the conductive member is pushed upward to close the electrical circuit between the contacts. The closure of this electrical circuit is detected by a microcomputer connected to the contacts. If the gas pressure is low, the electric circuit formed by the conductive member will not be closed between the contacts, and this state will be detected by the microcomputer. It is desirable to program the microcomputer to perform correct operations when the gas pressure is low.

Furthermore, it is desirable that the microcomputer monitor the gas pressure before and after ignition.

Another feature of DI devices is to change the means for providing an indication of device status and fault type. Preferably, such means includes a removably provided module with a built-in power supply, a part of which is provided with a digital display device, on the microcomputer.

When this module is connected to a microcomputer, the presence or absence of a failure in the device and its status, or simply the status of the device, is displayed numerically on the digital display E.

For example, different numbers on the IF display I: are used to indicate failure of the ignition element, failure of the 11 circuit, extinction of the flame, failure of the ignition element to reach the ignition temperature, etc. It is actually contemplated that this module can be used by maintenance personnel when inspecting and repairing equipment.

When a microcomputer is used to control the operation of the device,
This is effective in shortening the response time of the device, and at the same time greatly improves overall fuel efficiency and safety.

Also, the reliability of the device is improved by reducing the number of moving parts.

The preferred system preferably includes means for making programming changes that eliminate the use of specific inputs to the microcomputer for special applications.

The apparatus of the preferred embodiment of the invention described below is described for application to a scum-fired boiler. However, it will be obvious to those skilled in the art that the present invention is widely applicable to the control of gas combustion application devices such as household ranges and dryers.

Next, an apparatus according to an embodiment of the present invention will be described in detail.

In FIG. 1, a device 6 for applying the invention to fuel ignition and temperature detection is designated by the reference numeral 10. As shown in the figure, a microcomputer 4JA4, such as C0P411L manufactured by National Semiconductor Corporation, has an input/output device, a read-only memory, an external access memory, a microprocessor, etc. on one chip.
1 circuit chip 12 is included. Such an integrated circuit chip 1
2 incorporates a control program that can be generally programmed using machine language written in COP assembly language, for example.

Other elements of the system 10 shown in FIG. 1 include a burner 14, an ignition element 16, a pilot valve assembly 18, and a secondary valve assembly 2.
0, a pressure sensitive switch 22, a thermostatic control 1124, a low limit switch 22, a plug-in diagnostic module 28, and a power supply 30, the functions of each of which are detailed below. Ru.

In the general view of FIG. 1, an integrated circuit chip 12 is held within a module or housing 32. As shown in FIG. Housing 32 contains the interface circuitry of integrated circuit chip 12, as well as other components of device IO. The interface circuit will be described later in conjunction with FIGS. 3A and 3B, which schematically show the device 10. The housing 32 is provided with an indicator light 34 and a reset switch 36. These are largely connected to the integrated circuit chip 12. Standard AC117
V? f, each -E source from the power source 30 containing the source is connected to the housing 3
2 and various other elements of the device IO. The housing 32 is attached to a control panel near a controlled device such as a boiler using screws or the like.

, <-ners 14 are conventional, for example of the type used in gas-fired boilers. This typically includes a cylindrical member 38 with a plurality of apertures 40 provided therein. Referring to FIGS. 1 and 2, 1. The ignition device 16 includes an ignition element 17 fixed to one end of an insulating block 42 attached to a bracket 46 extending from the burner 14 with a screw 44. In this state, the ignition element 17 is supported near the burner 14 and achieves both the function of igniting the gas flow from the burner 14 and the function of detecting the temperature of the flame resulting from ignition. A pair of lead wires 48 extending from the other end of the insulating block 42 connects the /\cow/g 32 and the ignition element 17.

Ignition elements 17 suitable for construction with apparatus 10 are commercially available.Ignition elements 17 take advantage of the decrease in resistance of silicon carbide as the degree of carbonization increases. -Ill
The ignition element F17 is commercially available as a package including an insulating block and lead wires.

For example, Emanφ Electric Co., Ltd.'s
767 A fi17 manufactured by Rogers Division
Silicon carbide ignition elements are suitable for use with device 10.

Those skilled in the art understand that each ignition element f has its own temperature characteristics. i.e. 100″F
This means that when one ignition element exhibits a specific resistance value, the other ignition element exhibits a different resistance value even at the same temperature. Therefore, an automatic ignition system that can be adapted to different ignition elements cannot compensate for these differences. 4) μλ
Na m νC is sufficiently L+7.

The waste passes through a 1-jr long pulp array before being fed to burner 14. An example of a valve with such a configuration is Emerging Electric Company's Why)-
There is a product manufactured by the Rogers division with model number 36c84. As shown, bodies 18, 20 are preferably of the solenoid operated type, with cores 50, 52
and drive coils 54 and 56, respectively. 3, a relay 55 held within the housing 32 and connected via an interface to the integrated circuit chip 12 connects the coil 54, and a relay 57 connects the coil 54.
6 is operated. Valve 58.60 is connected to core 50.52. The valve seats 62, 64 for the valves 58, 60 are preferably formed within a chamber 66 of the casting forming a passage for the supplied gas. As is clear from Figure 1, the debris is in burner 1.
4, it must pass through the opening defined by the two JR seats 62 and 64. In Figure 1, jp5B
.

60 indicates the position of the closed ■. In this state, the flow of gas from chamber 66 toward burner 14 is blocked. valve 5
8, 60 open, gas enters the burner 14 through one defined orifice 68.

Pressure sensitive switch 22 includes a conduit portion 70 that communicates with the gas flow defined by chamber 66 between valve seats 62 and 64. The conduit portion 7o communicates with a large chamber 72 in which a diaphragm 74 is slidably supported. When the diaphragm 74 reaches its maximum position, the conductive member 76 fixed to the diaphragm 7jll comes into contact with the contacts '7a and go. The meaning of this will be explained later. Suffice it to say at this point that when valve 58 is open and the gas pressure is above the minimum value considered safe, it is ensured that diaphragm 74 is in the first position.

Thermostat 24 is conventional such as those used to control the operation of gas-fired boilers or similar equipment. As will be discussed in more detail below, when heat is required at thermostat 24, device 10 is activated to initiate an ignition sequence. F limit switch 2
6 is a safety device which preferably includes a temperature sensitive switch arranged to sense the temperature of the temperature chamber.

As will be explained in more detail below, if the chamber heats up, for example due to a fan failure, the integrated circuit chip 12 automatically blocks the supply of gas to the relay 55, 57 burner 14 by opening the l1 limit switch 26.

A plug-in diagnostic module 28 connectable to the housing 32 via a repiptacle 82 includes a digital display 8
Contains 4. When the plug-in diagnostic module 28 is connected to the housing 32, as described in more detail below, the display 84 provides information indicating the status of the device 10, including the status and presence of faults. Failures, defects, etc. in the device IO are indicated by lighting of the indicator light 34.

The 3rd IJ (A
), a circuit diagram of the device 10 is shown in FIG. 3(B). A detailed explanation of each circuit element will be omitted. The operation of each circuit element will be sufficiently clear to those skilled in the art. As for the integrated circuit chip 12, as mentioned above, it is generally programmed using the COP assembly language. l +Nr 4L Jl. 4
X- -1 m +1. J+: −1 −/J/
' M # > Book -1 rrs W 4COP41L
It is preferable to use an L″-f microcomputer.

The operation of the system 10 will be described with particular reference to the flowcharts shown in FIGS. 4-9.

To explain the operation of device #0, it is assumed that there is no flame at first. In this state, integrated circuit chip 12 maintains device 10 in an idle mode (FIG. 4). In idle mode, the integrated circuit chip 12 continuously
6. Each input of the thermostat 24 and pilot valve relay liner 55 is monitored. As shown in FIG. 3, the thermostat 24 and the north limit switch 26 are connected in series and input to the L5 input of the integrated circuit chip 12 via the IC 3a.

As is clear from FIG. 4, the device lO is activated until the relay driver 55 of the pilot valve is activated via the DI small output Q2 of the integrated circuit chip 12 or a human input signal of the thermostat/high limit switch is applied for heating. to remain in idle mode.

If pilot relay 55 is shorted, integrated circuit chip 12 enters a fault mode. The operation of device IO in fault mode F will be detailed later.

As shown in FIG. 4, integrated circuit chip 12 is programmed to not ignite unless the current in ignition element 17 exceeds the dark value current. For example, a current threshold i1 of 100 mA is set. This means that while the ignition element 17 does not draw the set current value from the power supply circuit, the integrated circuit chip 12
This is achieved by applying the L5 signal via IC3a so as not to ignite.

Assuming there is no malfunction, and when a heating request is issued by the thermostat, integrated circuit chip 12 delays the start of the ignition sequence for, for example, 30 seconds to pre-purge.

After a 30 second delay time, the circuit chip 12 is connected to the fifth circuit.
Enter the ignition mode shown in the figure.

When entering the ignition mode, the integrated circuit 3-way chip 12 reduces the dark value current of the thermostat, and then tests the ignition terminal 17 by measuring the resistance value. 6 If the ignition element 17 is short-circuited, the integrated circuit chip 12 12 enters fault mode. If there is no failure, integrated circuit chip 12 turns on Q2 to drive the pilot valve relay, energizing relay 55 and opening pilot valve 58. Preferably after one second, integrated circuit chip 12 again monitors thermostat 24 and low limit switch 26 power. If open, the heating request disappears and the integrated circuit chip 12
Go to off or mode.

As is more clearly seen in the flowchart shown in FIG. 8, upon entering the casual off rumor mode, the integrated circuit chip 12 goes into idle mode at 10 seconds and the pilot block 5B is closed. The integrated circuit chip 12 activates the pressure-sensitive switch 22 when the thermostat and the switch are closed.
Next check the scum pressure by monitoring. If the scum pressure is normal, the scum flowing through the pilot valve 58 to the conduit section 70 and the connected chamber 72 will flow to the diaphragm 7.
4 is moved to contact the 4-conducting member 76 with the contacts 78, 80 to close the circuit to the integrated circuit chip 12.

If the contact point 78.80 tab 12 on the integrated circuit chip 12
goes into low pressure mode.

Operation of device 10 in low pressure mode is detailed below.

Once the gas pressure is confirmed, the integrated circuit chip 12 is turned on.
Enter the mode. At this point, integrated circuit chip 12 prepares device 10 for igniting the gas.

Next, in order to energize the ignition element 17, the transistor Ql is turned on to drive the ignition element relay 15, and the 6 ignition element 17 that energizes the ignition element relay drive circuit is sufficiently heated for gas ignition. At this time, the waste begins to be fed to the burner 14.

As previously mentioned, in order to identify when a particular ignition element has reached its ignition temperature, integrated circuit chip 12 must overcome the problem of differences in the different temperature characteristics of different elements. 6th
As shown, to identify that the ignition element 47 has reached its ignition temperature, the integrated circuit chip 12 performs two tests: a warm test and a hot test. First, the integrated circuit chip 12 is exposed to the ignition element 17 during low temperatures.

That is, before the ignition device 7116 is energized, a threshold value is formed based on the resistance value of the ignition element 17.9 Then, after the ignition device 16 has been energized for, for example, 2 seconds, the Nr J moxibustion ignition element 17 is activated.
The resistance value of is measured. If the read resistance value is E(
If less than or equal to fi, the ohm test is passed.

If the warm test is not passed, the igniter 16 is turned on, for example for 2 seconds, the resistance of the ignition element 17 is measured, and the new value is compared with the cold sowing reference value. Will this process pass the warm test?
Alternatively, the process continues until, for example, one minute has elapsed. If the warm test does not pass after one minute, integrated circuit chip 12 enters a fault mode.

If the warm test passes, integrated circuit chip 12 is then hot tested. In this test, integrated circuit chip 12 compares two successive measured resistance values at igniter f17. If the difference between the results read by the first resistor is less than or equal to a predetermined value, this indicates that the hot test has been passed and a flat portion, that is, a high temperature portion in the temperature characteristics of the ignition element 17 has been reached. If the hot test is not passed, the ignition element 17 is energized for, for example, two seconds and both the warm test and the hot test are performed again. This continues until the hot test passes or one minute has elapsed. If the hot test does not pass within one minute, integrated circuit chip 12 enters fault e mode.

1.7%1IpRrJan)St-Nno”Jl-)1
(2r - 4 people 1kl + 1 road is input to the nap 12.) By using the above-mentioned technique to check the ignition temperature, it becomes possible to ignite even if the power supply voltage drops.

Once the ignition temperature is confirmed, the integrated circuit nap 12 or FIG.
The transistor Q3 is activated to drive the relay 57 for the second valve, and the relay drive circuit for the second valve is activated to open the second valve 60. At the same time, the igniter 7-17 is energized. At this point gas is supplied to the burner 14 via the chamber 66 and the defined orifice 68 and then to the opening 40 in the vicinity of the ignition element 17 where it is ignited. Also, k) the ignition pixel f-17 is deenergized, preferably after 4 seconds.

At this point, the ignition element 17 functions as a temperature detection element. Finally, the integrated circuit chip 12 is in flames.

As explained below, when the flame is extinguished, the accumulation 1jjJ
The circuit chip 12 is programmed to perform regenerative operation.

Since the integrated circuit chip 12 detects flame extinction based on the resistance value of the ignition element 17, the integrated circuit chip 12 must have the ability to guarantee changes in temperature characteristics in different ignition elements. To determine whether flame extinction has occurred, integrated circuit chip 12 performs two tests: a level test and a ratio test.

Referring to FIGS. 7 and 8 IgJ, after the igniter is de-energized, a threshold value is determined based on a measurement of the resistance of the ignition element 17 on the integrated circuit chip 12 just before the igniter heats up, for example 2 seconds later. It is formed. This threshold value is equal to the measured value increased by a predetermined value, that is, when the resistance value of the ignition element 17 exceeds the threshold value, it is confirmed that the temperature in the vicinity of one ignition element 17 has decreased and the flame has disappeared. The threshold resistance value is determined to indicate that the resistance value is sufficient to The ratio test is accomplished by comparing the rate of change in resistance of the ignition element 17 to a predetermined ratio.

As shown in FIG. 8, when the rate of change in resistance of the ignition element exceeds twice the preset rate, a continuous temperature drop in the vicinity of the ignition element 17 is indicated and flame extinction occurs.

Upon extinguishing the flame, integrated circuit chip 12 returns to idle mode after 10 seconds. As the thermostat 24 continues to generate heating requests, the integrated circuit chip 12 repeats the above-described firing sequence to generate a flame, and the extinction counter indicates that three flame extinctions have occurred during a single operation. When indicated at , integrated circuit chip 12 enters a fault mode.

When the integrated circuit chip 12 enters the monitor mode as shown in FIG. 8, in addition to monitoring the flame, the integrated circuit chip 12 continuously controls the ignition element 17 via IC3c, the thermostat, and the upper limit input via IC3a. The human power of the pressure sensitive switch 22 is monitored via the IC3b, and the pilot relay and drive circuit are monitored via the IC3d.

As shown in FIG. 8, if the ignition element 17 is short-circuited or the pilot valve drive circuit fails, the integrated circuit chip 1
2 goes into fault mode.

When the thermostat 24 or high limit switch 26 is opened, the integrated circuit chip 12 is activated to return the device to an idle mode as shown in FIG. 4, indicating a drop in gas pressure. enters a low pressure mode as shown in FIG.

In low pressure mode, integrated circuit chip 12 closes pilot jt and second valve 58,60. Figures 4 and 5
After a delay time of 30 seconds as shown in the figure, integrated circuit chip 1
2 goes into ignition mode] A two-part ignition sequence is performed.

This sequence ends with a gas pressure check.
This sequence is repeated while the gas pressure is low. As shown, the closure of switch 22 indicates that gas pressure has been restored and integrated circuit top 12 enters a turn-on mode. The operation of device 10 in turn-on mode is as previously described in detail.

In the event of an abnormality such as a short circuit in the relay drive circuit, the flame going out three times, or a failure, the integrated circuit chip 12 enters the fault mode as described above. A flowchart in fault mode is shown in FIG.

In the fault mode, as shown in Figure 9, the pilot valve P
5B and the second valve 6o are closed to prevent gas flow and the ignition element 17 is deenergized. If the integrated circuit chip 12 can be operated using an external power source, the reset switch 36 including the push button is pressed and the integrated circuit chip 12 is in the starting state (Fig. 4).
It will continue until it returns. Of course, if the fault is not recovered, the integrated circuit chip 12 will enter the fault mode again when the abnormal element is checked. When the device reenters fault mode, indicator light 34 visually indicates the presence of a fault. However, if the device IO completely fails, the indicator light 34 may not light up due to the entire power being lost.

Furthermore, it is desirable to have means for displaying the status of the failure when a failure occurs. This function is accomplished by a plug-in diagnostic module 28 that displays the status of the device 10. The diagnostic module 28 is clearly intended for use by maintenance personnel. Diagnostic module 2 as mentioned above
8 is configured with a common decoder try 83 and a 7 segment digital display 84. As shown in FIGS. 1A to 3, a self-powered diagnostic module 28 is inserted into the receptacle 82 and connected to the integrated circuit chip 12. Digital display 84 displays numbers indicating the type of failure or status of a particular device.

For the device 10 described with reference to FIGS. 4-9, a reading of ``zero'' indicates that the power level is insufficient to operate the device; indicates idle mode, "2'" indicates input of thermostat and upper limit switch, "3" indicates ignition mode, "4" indicates ■GNOK mode, "55 Pass pressure decrease, 6" indicates idle 7'' indicates improper pilot JT opening in mode and 7'' indicates ignition system failure, respectively.

To accommodate a particular application, device 10 is preferably provided with means for altering the functionality of integrated circuit chip 12 to vary the operating modes described above. Referring to FIG. 3, it is preferred that a particular input terminal (L7) of integrated circuit chip 12 be ungrounded for this purpose.

As shown in Figure 3, a removable member (a strap in Figure 3) connects the input and ground to make it ungrounded.
°'). This electrically conductive member is preferably installed at the factory and forms part of the interface circuitry within the housing 32. Strap “a°
Removal of ``2'' eliminates the 30 second pre-purge time before integrated circuit chip 12 enters ignition mode (see FIG. 4). This modification is used, for example, when rapid heating is required. When strap "a'" is removed, integrated circuit chip 12 preferably enters the fault mode with one flame extinguishment, rather than three flame extinguishments as shown in FIG. This prevents the buildup of gas that occurs when three ignitions occur without a 30 second interval. It will be appreciated that additional functionality may be programmed into integrated circuit chip 12 by removing other straps, not shown, if desired.

In the above detailed description, the ignition element 17 is used to determine the temperature characteristics.
It was mentioned that the resistance value of the resistor is measured. However, it will be clear to those skilled in the art that similar information can be obtained by measuring, for example, the voltage drop across the terminals of the ignition element or the current flowing through the ignition element.

It will therefore be understood that in applying the phrase "resistance measurement°" to an ignition element, consideration should be given to voltage or current measurements that yield information determining the temperature characteristics of the ignition element. Information on the temperature characteristics of the ignition element is obtained by measuring the voltage drop across the terminals of the ignition element.

Although a preferred embodiment of the present invention has been illustrated and described in detail above, it is clear that the embodiment can be modified without departing from the spirit of the present invention.

[Brief explanation of the drawing]

FIG. 1 is a partial circuit diagram of an embodiment of an automatic ignition and temperature detection device according to the present invention. FIG. 2 is a front view showing a method of holding the ignition element near the burner. 3(A) and 3(B) are circuit diagrams of the apparatus shown in FIG. 1, and FIGS. 4 to 9 are flowcharts showing the operation of the apparatus according to an embodiment of the present invention. In the diagram, ■? ... integrated circuit chip, 14 ... burner, 16 ... ignition device, 17 ... ignition element, 22 ...
・1 switch, 24...Thermostat, 26・
. . . limit switch, 28 . . . diagnostic module. Patent applicant Lam Products

Claims (2)

[Claims] (1) A burner having a spout, a power source, a normally closed fuel valve that controls gas supplied to the burner, and the jP
11j, an opening means for opening the burner; An automatic ignition device comprising a resistance ignition means having resistance-temperature characteristics, a detection means for repeatedly measuring the resistance value of the resistance ignition means in a predetermined period and comparing the measured values, and the detection means said valve opening means to open said valve when the resistance-bias characteristic of said resistive ignition means is in a region sufficient to ignite said gas due to the difference between said valve opening measurement; Automatic ignition and combustion detection device in a gas combustion device, comprising: (2) Turning the detection means and the valve opening means into operation Q (r)
The automatic ignition and combustion detection device in the gas combustion bag d according to claim 1, characterized in that -12 includes a microcomputer.