JP2002031336A - Combustion control device for gas burner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a combustion control device for a gas burner, formed such that a gas amount of input can be throttled to a small fire limit value of a burner, despite the change in the kinds of gases and fluctuation of gas pressure, a wide range of a thermal power can be obtained and a flame failure during small fire can be prevented from occurring. SOLUTION: The combustion control device comprises a valve part to control a gas flow rate; a drive part to electrically drive the valve part; and a thermocouple 3 to detect the flame of the burner 1 by a thermoelectromotive force. The combustion control device of a gas burner is formed, so that the electromotive force is read in a burner controller 10 to control a gas amount. When, after a valve part is moved to a given small fire position once during a use of small fire, a gas flow rate is further throttled as the thermoelectromotive force is read, control through which combustion is effected in a minimum small fire state is effected by the burner controller 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion control device for a gas burner, and more particularly to a combustion control device suitable for use with a small fire.

[0002]

2. Description of the Related Art In recent years,
There is a need to cook on a small heat with a gas stove, and various gas stoves that can be cooked on a small fire have been provided. However, conventional gas stoves of this type have a structure in which only a small amount of gas is squeezed to burn when set to a small fire, so combustion can be reduced to the minimum small fire condition close to the limit of small fire. And could not meet the need for a smaller fire.

That is, the input of gas in the state of a small fire has been set to be larger than the small fire limit value of the burner in consideration of fluctuations in gas type and gas pressure. For example, when the small fire input is set to 0.465 kW (400 kcal / h), the small fire limit value when the gas type is 13 A is 0.31.
kW (267 kcal / h). Conversely, despite the fact that the gas amount can be reduced to 0.31 kW, the small fire input is reduced to 0.465 kW for the above-mentioned reason.
I had to make it.

[0004] In addition, if the small fire is constant and unchanged, and the thermoelectromotive force of the thermocouple for detecting the flame of the burner falls below a threshold value due to wind or the like, there is a possibility that the fire is determined to be a misfire and the fire is extinguished.

The present invention has been made in view of the above description, and it is possible to reduce the input gas amount to the small fire limit value of the burner irrespective of the variation of the gas type and the gas pressure, so that a wide heating power range can be obtained. An object of the present invention is to provide a gas burner combustion control device which can be obtained and can prevent misfire at the time of a small fire.

[0006]

According to the present invention, there is provided a gas burner combustion control apparatus for controlling a gas flow rate, a drive section for electrically driving the valve section, and a burner flame. A thermocouple that detects the thermoelectromotive force by using a thermoelectromotive force, and reads the thermoelectromotive force into a burner controller to control the amount of gas. After moving the section, the gas flow rate is further reduced while reading the thermoelectromotive force, and when the predetermined thermoelectromotive force is reached, control for burning in this minimum small fire state is performed by a burner controller. . By doing so, it is possible to reduce the input of gas to the small fire limit value while checking the combustion of the burner and burn it in the minimum small fire state, regardless of the gas type and gas pressure fluctuation. The input can be narrowed down to the small fire limit of the burner, and a wide range of thermal power can be obtained.

In the above-described combustion control device for a gas burner, the thermoelectromotive force is read from a small fire position of the valve portion.
It is also preferable that the control is performed such that the minimum fire state is achieved while changing the amount of movement of the valve section according to the value of the detected thermoelectromotive force. By controlling in this manner, even a burner or a gas that requires delicate valve movement can be quickly reduced to the small fire limit value of the burner without misfiring.

In the combustion control device for a gas burner, when the thermoelectromotive force at the minimum small fire position falls below a predetermined value for a certain period of time, the valve portion is increased in a direction to increase the gas amount until the thermoelectromotive force becomes a predetermined thermoelectromotive force. It is also preferable to control the valve to shut off the supply of gas when the thermoelectromotive force does not increase even if the valve is moved in the direction of increasing the gas amount by moving the valve. When the thermoelectromotive force at the minimum small fire position falls below a predetermined value for a certain period of time, by controlling the valve to move in a direction to increase the gas amount until the predetermined thermoelectromotive force is obtained, the minimum small fire is controlled. Sometimes the flame just before a misfire due to wind etc. (a continuous thing such as a ventilation fan) can be controlled to recover by increasing the thermal power,
Prevents misfiring during small fires. Also, if the thermoelectromotive force does not increase even if the valve unit is moved in the direction to increase the gas amount, by shutting off the valve and stopping the gas supply,
In the event of a misfire, the supply of gas can be shut off to ensure safety.

In the above-described gas burner combustion control device, it is preferable that the valve portion is a closing member having a gas passage for changing a gas flow rate from large to small by rotation. By doing so, the heating power can be finely adjusted as compared with the needle valve system, and particularly, the heating power at the time of small fire can be finely adjusted.

In the gas burner combustion control device, a main gas passage and a small fire gas passage are provided as gas passages in the closing member, and the main gas passage and the small fire gas passage overlap with a part that is opened. It is also preferable that a portion that does not open is provided, and an orifice for determining a small fire is provided in a flow path communicating with the small fire gas passage. A main gas passage and a small fire gas passage are provided as gas passages in the closet, and a main gas passage and a small fire gas passage are provided with a portion that opens overlapping and a portion that does not open. By adjusting the opening degree of the gas passage and the opening degree of the small fire gas passage, the heating power can be adjusted in a wide range, and the heating power can be continuously adjusted by overlappingly opening portions. By providing an orifice in the flow path that communicates with the small fire gas passage, the amount of gas can be regulated by the orifice when a small fire is set, and the rotational accuracy of the closet and the machining tolerance of the closet are rough. Even so, the problem that the flame is too large or too small to cause a misfire when the small fire is set is eliminated.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a system diagram of an entire gas stove. In this embodiment, there are three burners 1a and one grill burner 1b as burners 1. The burner 1 is provided with an ignition plug 2 for igniting the burner 1 and a thermocouple 3 for detecting the flame of the burner 1 by thermoelectromotive force. The gas supply path 5 for supplying gas from the gas inlet 4 branches into four paths and communicates with each burner 1. An electromagnetic valve 6 for opening and closing the gas supply path 5 is disposed before the four branches of the gas supply path 5, and a gas flow rate adjusting unit 8 is disposed at each of the four branches of the gas supply path 5. . In the gas supply path 5 for supplying gas to the grill burner 1b, a governor 9 for adjusting the pressure before the gas flow rate adjusting unit 8 is disposed.

Each burner 1 is controlled by a burner controller 10 having a control circuit. By operating each ignition / extinguishing button 11, the ignition or extinguishing of each burner 1 is performed via the burner controller 10. By controlling each of the heat power adjustment buttons 12, the respective gas flow rate adjusters 8 are adjusted via the burner controller 10 so that the heat of each burner 1 is adjusted. I have. When the burner 1 is ignited, the igniter switch is turned on, power is supplied to the igniter 13, and the ignition plug 2 is discharged. Thermocouple 3
Is input to the burner controller 10, whereby the electromagnetic valve 6 and the flow rate adjusting unit 8 are controlled by the burner controller 10. A and A 'in FIG.
B and B ', C and C', D and D ', E and E', and F and F 'are electrically connected.

The solenoid valve 6, governor 9 and flow rate adjusting section 8 arranged in the gas supply path 5 are integrated into one body 7 as shown in FIGS. In the portion of the solenoid valve 6, a valve hole 31 is provided in the gas supply path 5,
It is opened and closed by a valve body 33 driven by an electromagnetic actuator 32. Each of the four gas supply paths 5 branched downstream from the solenoid valve 6 is provided with a flow rate adjusting unit 8. The flow rate adjusting unit 8 communicating with the grill burner 1 b is a flow rate adjusting unit 8. The governor 9 is arranged further upstream.

In the flow rate adjusting section 8, a closing member 15 is rotatably mounted as a valve section for adjusting the flow rate. The inside of the closing member 15 is a cavity 16 and communicates with the inside of the cavity 16 and the gas inflow passage 17 of the body 7. The closing hole 15 is provided with a main closing hole 18 and a small fire closing hole 19 as gas passages for communicating the inside of the cavity 16 and the outer periphery of the closing portion 15, and the main closing hole 18 is connected to the main gas passage. At the same time, the small fire closing hole 19 serves as a small fire gas passage. The main closing hole 18 and the small fire closing hole 19 are displaced in the axial direction of the closet 15 and displaced by about 90 ° in the circumferential direction. Closure 15 in body 7
A main gas outflow passage 20 and a small fire gas outflow passage 21 are provided at positions on the outer circumference of the main gas outlet, and the end of the main gas outflow passage 20 is made to correspond to the main closing hole 18 and the small fire gas outflow passage is provided. The end of the passage 21 is made to correspond to the small hole 19 for small fire. A small fire orifice 23 is provided in the small fire gas outflow passage 21, and the diameter of the small fire orifice 23 is sufficiently smaller than the diameter of the small fire close hole 19. The main gas outflow path 20 and the small fire gas outflow path 21 are joined to and communicate with one outlet flow path 22, and the outlet flow path 22 is connected to the burner 1. The main closing hole 18 includes a circular hole 18a and a pair of wedge-shaped grooves 18b and 18c communicating with the hole 18a. The small fire closing hole 19 also includes a circular hole 19a and a pair of wedge-shaped grooves 19b and 19c communicating with the hole 19a. The wedge-shaped groove 18c and the wedge-shaped groove 19b are configured to open when the closing element 15 is rotated. That is, the section a in FIG. 10 is an overlapped part that is overlapped and opened, and the section b is a non-overlapping part that is not overlapped and opened.

The closing member 15 is driven to rotate by an electric motor 24 such as a stepping motor. The rotation of the electric motor 24 is transmitted to a speed reduction mechanism 25 and the speed reduction mechanism 2 is rotated.
The rotation is transmitted from the output shaft 26 of the No. 5 to the closer 15. The output shaft 26 of the speed reduction mechanism 25 and the closing member 15 are connected via a joint 27 and a closing spring 28.
The output shaft 26 of the speed reduction mechanism 25 is provided with a rotation position detection sensor 29 for detecting the rotation position of the closing member 15.

When the motor 15 is driven to rotate by the electric motor 24, the gas passage is opened and closed by the motor 15 as shown in FIGS. 7 (a), 7 (a) 'to 7 (e) and 7 (e)'. FIG. 7 (a)
In the fully open position (a) ′, the rotation angle is set so that the gas passage area of the main closing hole 18 is maximized, and gas is supplied to the burner 1 only through the main closing hole 18. FIG. 7 (b)
In the state of the intermediate thermal power 1 of (b) ', the gas passage area of the main closing hole 18 is smaller than the fully open position, and the gas amount supplied to the burner 1 is reduced by the reduced gas passing area of the main closing hole 18. Less. In the state of the intermediate thermal power 2 shown in FIGS. 7 (c) and 7 (c) ', the main closing hole 18 is about to be closed and the small opening hole 19 starts to be opened (the wedge-shaped groove 18c and the wedge-shaped groove 19b overlap. And the gas passing through the main hole 18 and the small fire orifice 23 through the small fire hole 19.
Is supplied to the burner 1. FIG. 7D
At the small fire position (d) ', the main hole 18 is closed and the small hole 19 is open, and only the gas that has passed through the small hole orifice 23 from the small hole 19 is burner 1. Supplied to At this small fire position, the gas amount is determined by the hole diameter (area) of the small fire orifice 23. FIG. 7 (e) (e) ′
In the minimum small fire state, the gas passage area of the small fire hole 19 is narrowed from the small fire position, and the gas amount is narrowed to the limit value to supply the gas to the burner 1. When the closer 15 is further rotated in the direction to close from the minimum small fire state, the main close hole 18 and the close hole 19 for small fire are closed to be in a fully closed state.

When the minimum fire condition is set, the gas amount is reduced to the limit value of the burner 1 in accordance with the thermoelectromotive force of the thermocouple 3 for detecting the flame of the burner 1. It is known that there is a relationship between the gas input and the thermoelectromotive force near a small fire when the input becomes smaller. Therefore, by reading the thermoelectromotive force, the input at that time can be indirectly known. The present invention utilizes this fact to control the burner controller 10 to reduce the fire to the minimum small fire state. In other words, the closing 15
Then, while reading the thermoelectromotive force of the thermocouple 3, the gas flow rate is further reduced, and when the thermoelectromotive force reaches a predetermined value, the combustion is controlled so as to burn in a minimum small fire state. In addition, the thermoelectromotive force is read from the small fire position, and control is performed so that combustion is performed in the minimum small fire state while changing the size of moving the closet 15 with the detected thermoelectromotive force. Further, when the thermoelectromotive force falls below a predetermined value for a predetermined time in the minimum small fire state, the closing element 1 is increased in the direction of increasing the gas amount until the thermoelectromotive force reaches the predetermined thermoelectromotive force.
5 is controlled to move. In addition, when the thermoelectric power is not increased by moving the closing member 15 in a direction to increase the gas, the closing of the closing member 15 is controlled so as to shut off the gas supply.

FIG. 2 shows a flowchart of a specific example of the above control. When the fire power adjustment button 12 is pressed to make a small heat while burning with a large fire (an operation of pressing the fire power stage 1 which is the minimum heat), the electric motor 24 rotates the closet 15 to the small fire position. Then, it is determined whether or not the time after the ignition of the burner 1 has elapsed, for example, 3 minutes or more.
This is because if the burner 1 is cold, if the thermal power is further reduced, there is a high risk of misfiring, so that the combustion time from ignition is, for example, 3 minutes or more. Then, for example, 10 seconds are waited until the thermoelectromotive force is stabilized after the small fire. This is because it takes about 10 seconds until the thermoelectromotive force of the thermocouple 3 is stabilized when switching from large fire to small fire due to the heat capacity of the thermocouple 3. Then, while detecting the thermoelectromotive force of the thermocouple 3, the electric motor 24 is driven to control the gas amount to a limit value that does not cause a misfire, and to control the combustion in the minimum small fire combustion state.

For example, when the thermoelectromotive force E is 5 seconds average, E> 4.
It is determined whether it is 35 mV, and when the thermoelectromotive force is higher than 4.35 mV, the electric motor 24 is rotated in the small fire direction for two steps and waits for 5 seconds. While the thermoelectromotive force is higher than 4.35 mV, the electric motor 24 is repeatedly rotated in the direction of the small fire for two steps and kept on standby for 5 seconds, thereby gradually reducing the fire.
When the thermoelectromotive force becomes lower than 4.35V, the thermoelectromotive force E becomes 5
It is determined whether E> 3.8 mV on average, and the thermoelectromotive force is 3.8 m.
If it is higher than V, the electric motor is rotated in the small flame direction by one step and waits for 2 seconds. As long as the thermoelectromotive force is higher than 3.8 mV, the electric motor 24 is repeatedly rotated in the direction of small fire for one step and kept on standby for 2 seconds, thereby gradually reducing the fire. When the thermo-electromotive force is lower than 3.8 mV, it is determined whether the thermo-electromotive force E is E> 3.25 mV on average for 5 seconds. When the thermo-electromotive force is higher than 3.25 mV, it is determined again that E> 3.8 mV. Control in the same way. When the thermoelectromotive force is lower than 3.25 mV, the electric motor 24 is rotated in the direction of the large fire by two steps. It is determined whether or not the thermoelectromotive force has increased on average for 5 seconds after rotating the electric motor 24 in the large fire direction for two steps.
When it is determined that the thermoelectromotive force has increased, E> 3.25 again
The control is performed in the same manner by determining whether the voltage is mV. If it is determined that the thermoelectromotive force does not increase, it shifts to the misfire mode as
Is controlled so as to shut off the supply of gas by moving so as to fully close. It should be noted that the determination made by taking an average of 5 seconds of the thermoelectromotive force as described above is an average value of 5 seconds because the thermoelectromotive force is unstable due to the influence of the breeze and the like. Electric motor 24
The reason why the motor is rotated to wait for 5 seconds or 2 seconds is to secure a stable time of the thermoelectromotive force. By controlling according to the above-described flowchart, the input can be reduced to the small fire limit value of the burner 1 regardless of the variation of the gas type and the gas pressure, and the combustion can be stably performed so as not to misfire in the minimum small fire state. Can be done.

The main closing hole 18 of the closing member 15 has a circular hole 18a and a pair of wedge-shaped grooves 18b, 1b communicating with the hole 18a.
8c, and the small fire opening 19 is also a circular hole 19
a and a pair of wedge-shaped grooves 19b and 19c communicating with the hole 19a.
(A gas passage that changes the gas flow rate from large to small), so that a very small amount of gas passage area can be adjusted by the rotation of the closing member 2. In particular, since the small fire closing hole 19 has the above-described structure, it is possible to adjust the gas flow rate when a small fire occurs.

The small fire gas outflow passage 21 is provided with a small fire orifice 23. The diameter of the small fire orifice 23 is sufficiently larger than the diameter of the small fire orifice 23.
Therefore, even when the closet 15 is slightly rotated from the arbitrary position to the small fire position, the small fire power can be accurately secured by the hole diameter of the small fire orifice 23. If the small fire orifice 23 is not provided with only the small fire closed hole 9, the closed
And high precision of other parts are required, and mass production is poor.

The wedge-shaped groove 18c and the wedge-shaped groove 19b are opened so as to be overlapped when the closing element 15 is rotated, so that the closing element 15 is rotated to close the main closing hole 8 and the small fire opening. There is no adverse effect such that the gas flow is interrupted during opening and closing of the child hole 9.

[0023]

According to the first aspect of the present invention, there is provided a valve section for controlling a gas flow rate, a drive section for electrically driving the valve section, and a thermocouple for detecting a flame of a burner by a thermoelectromotive force. It is a combustion control device of a gas burner for controlling the gas amount by reading the thermoelectromotive force into a burner controller,
When the small fire is used, the valve is once moved to the predetermined small fire position, and after reading the thermoelectromotive force, the gas flow rate is further reduced, and when the predetermined thermoelectromotive force is reached, the control for burning in the minimum small fire state is performed. Since the burner controller is used, the gas input can be narrowed down to the small fire limit value while the burner combustion is being checked, and the gas can be burned in the minimum fire state. Regardless, the input can be reduced to the burner's low fire limit,
A wide range of thermal power can be obtained.

Further, the invention of claim 2 of the present invention is directed to claim 1
In, because the thermoelectromotive force is read from the small fire position of the valve portion, and the control is performed to change the valve portion to move by the value of the detected thermoelectromotive force to the minimum small fire state, Even in the case of a burner or a gas that requires a delicate valve movement, the burner can quickly be reduced to the small fire limit value without misfire.

Further, the invention of claim 3 of the present invention is directed to claim 1
Alternatively, according to claim 2, when the thermoelectromotive force at the minimum small fire position falls below a predetermined value for a predetermined time, control is performed so as to move the valve portion in a direction to increase the gas amount until the thermoelectromotive force reaches the predetermined thermoelectromotive force. Therefore, it is possible to control the flame immediately before a misfire due to wind or the like (a continuous thing such as a ventilation fan) at the time of the minimum small fire by increasing the heating power, to prevent the misfire at the time of the small fire, and to reduce the gas. If the thermoelectromotive force does not increase even if the valve section is moved in the direction to increase the amount, control is performed to shut off the valve and shut off gas supply. It can be secured.

The invention of claim 4 of the present invention provides the method of claim 1
In any one of claims 3 to 3, the valve portion is a closer having a gas passage that changes a gas flow rate from large to small by rotation, so that the heating power can be finely adjusted as compared with a needle valve system, In particular, it is possible to finely adjust the heating power at the time of a small fire.

According to a fifth aspect of the present invention, in the fourth aspect, a main gas passage and a small fire gas passage are provided as gas passages in the closing member, and the main gas passage and the small fire gas passage overlap with each other. The opening of the main gas passage and the opening of the small fire gas passage can be adjusted over a wide range by adjusting the opening of the main gas passage and the opening of the small fire gas passage. The heat power can be continuously adjusted by the part that opens.The orifice that determines the small fire is provided in the flow path that communicates with the small fire gas passage. This eliminates the problem of flames being too large or too small and causing misfiring when a small flame is set, even if the rotational accuracy of the closet or the processing tolerance of the closet is rough.

[Brief description of the drawings]

FIG. 1 is a schematic system diagram of an entire gas stove according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating an operation of the above control.

FIG. 3 is a cross-sectional view seen from the front of a body in which the solenoid valve, the governor, and the flow rate adjusting unit are assembled.

FIG. 4 is a cross-sectional view as viewed from the side of FIG. 3;

FIG. 5 is a plan view of FIG. 3;

6 is a cross-sectional view illustrating a cross-sectional position in FIG.

7 (a) to 7 (e) are operation explanatory views of a section taken along line XX of FIG. 6, and FIGS. 7 (a) 'to (e)' are Y-
It is operation | movement explanatory drawing of the part cross section by the Y line.

8 (a) is a plan view and FIG. 8 (b) is a front view showing the same child.

FIG. 9A is a cross-sectional view of the above-described closet, and FIG.
(C) is a sectional view taken along line WW of (a).

FIG. 10 is an explanatory diagram illustrating a relationship between a main close hole and a small fire close hole according to the first embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Burner 3 Thermocouple 8 Gas flow rate adjustment unit 10 Burner controller 15 Closure 18 Main closure hole 19 Closed hole for small fire 24 Electric motor

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Akira Ota 1-152 Oka, Minami-shi, Minato-ku, Osaka-shi F-term in Harman Co., Ltd. 3H054 AA01 BB03 CA01 CA03 CC01 CC03 DD01 EE01 GG01 3H062 AA07 AA15 CC02 DD01 EE11 FF01 HH02 HH10 3K003 EA03 FA01 FA02 FB05 GA03 SA08 SC03 SC08 3K005 VA20

Claims (5)

[Claims] 1. A valve unit for controlling a gas flow rate, a drive unit for electrically driving the valve unit, and a thermocouple for detecting a flame of a burner by a thermoelectromotive force. A gas burner combustion control device for controlling the amount of gas by reading the thermoelectric force while reading the thermoelectromotive force after moving the valve to a predetermined small fire position when using a small fire, and further reducing the gas flow rate. A combustion control device for a gas burner, wherein control for burning in a minimum fire state when a predetermined thermoelectromotive force is obtained is performed by a burner controller. 2. The method according to claim 1, wherein the thermo-electromotive force is read from a small-fire position of the valve portion, and a control is performed such that the magnitude of the movement of the valve portion is changed according to the detected value of the thermo-electromotive force so as to minimize the fire. 2. The combustion control device for a gas burner according to claim 1, wherein: 3. When the thermoelectromotive force falls below a predetermined value for a predetermined time at the minimum fire position, the valve portion is moved in a direction to increase the gas amount until the thermoelectromotive force becomes a predetermined thermoelectromotive force, and the gas amount is reduced. 3. The gas burner according to claim 1, wherein the valve is shut off and the supply of gas is stopped when the thermoelectromotive force does not increase even if the valve section is moved in the increasing direction. Combustion control device. 4. The combustion control of a gas burner according to claim 1, wherein said valve portion is a closing member having a gas passage for changing a gas flow rate from large to small by rotation. apparatus. 5. A main gas passage and a small fire gas passage are provided as gas passages in the closing member, and a portion which is overlapped with the main gas passage and a small fire gas passage and a portion which is not opened are provided. 5. The combustion control device for a gas burner according to claim 4, wherein an orifice for determining a small fire is provided in a flow passage communicating with the small fire gas passage.