JP2001004130A - Combustion amount control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a combustion amount control device capable of accurately setting and controlling a combustion amount with excellent reproducibility and with fine resolution. SOLUTION: An apparatus comprises fuel supply variable apparatus 24 composed of a valve element 41 provided between an inlet 22 and an outlet 23 and a stepping motor 42 for driving the valve element 41, a burner 25 for combusting a fuel sent from the outlet 23, and a control section 32 for controlling the stepping motor 42 and controlling heating power. Therefore, an application pulse is sent from the control section 32 to the stepping motor 42 to drive the valve element 41 with fractional resolution, and hereby the combustion amount can be set and controlled accurately with excellent reproducibility.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion amount control device for electrically adjusting a combustion flow rate.

[0002]

2. Description of the Related Art Conventionally, this kind of combustion amount control apparatus has a structure shown in FIG.
(See, for example, JP-A-56-14)
7974, and JP-A-56-147975). FIG. 5 is a schematic configuration diagram of a conventional combustion amount control device. The electromagnetic coil 4 is formed by using a solenoid as an actuator from a gas supply source 1 such as a city gas pipe, an LP, and a gas cylinder via a shutoff valve 2 and a gas governor 3. The plunger 5 and the valve element 6 are driven by the exciting current to change the gap between the valve seat 7 and the valve element 6 to control the amount of combustion to be burned by the burner 9 via the proportional control valve 8 for adjusting the gas flow rate. In the control device, a rod 11 contacting the valve body 10 of the proportional control valve 8 from the side opposed to the plunger 5 to the top of the valve body 6 and an effective length of the rod 11 so as to regulate the minimum gas flow rate according to the gas type. An adjusting mechanism 13 including an adjusting screw 12 for adjusting the height is provided. In this conventional combustion amount control device, when the solenoid coil 4 is not energized, the proportional control valve 8 urges the spring 14 in the direction of bringing the valve body 6 into contact with the valve seat 7, but the rod 11 First, the valve body 6 contacts the valve body 6 to regulate the operation of the valve body 6, and acts to keep a gap corresponding to the minimum flow rate between the valve body 6 and the valve seat 7. Therefore, the valve body 6 does not close the valve seat 7. Therefore, the closing of the gas is performed by the closing valve 2 provided separately from the proportional control valve 8.

In this conventional example, a gas water heater is used, and a desired water temperature as a target value is inputted and instructed by a setting mechanism 15, and the water temperature from a water temperature detector 17 at the outlet of the heat exchanger 16 is detected. The signal is fed back to the adjusting unit 18 so that the adjusting unit 18
The comparison unit 19 and the discrimination unit 20 perform a comparison operation, and a flow rate operation signal is output to the proportional control valve 8.

In this conventional combustion amount control device, when the shut-off valve 2 is opened, the minimum gas flow rate passes through the gap between the valve seat 7 and the valve body 6 even if no current flows through the electromagnetic coil 4 of the proportional control valve 8. Flows and burns in the burner 9. When the hot water temperature detected by the hot water temperature detector 17 is lower than the set value, the control unit 18 outputs a control current, which is an operation signal, according to the difference between the set value and the detected value so as to increase the gas flow rate. The electromagnetic coil 4 is excited by the control current, the plunger 5 is attracted into the coil, the spring 14 is compressed, the valve body 6 is displaced to a position where the repulsive force and the attractive force of the solenoid are balanced, and the valve seat 7 and the valve seat 7 are displaced. And the gas flow rate increases.

When the gas flow rate increases, the hot water temperature increases, and when the difference from the set value decreases, the control current decreases, and the repulsive force of the spring 14 increases with respect to the attraction force of the solenoid. And the valve body 6 is again displaced to a position that balances the suction force of the solenoid to reduce the gap with the valve seat 7. Further, the switching mechanism 21 switches the range of the control current of the proportional control valve 8 with respect to gas types having different heating values and supply pressures of the fuel gas, and in some cases, changes the valve body 6 and the valve seat 7 to appropriate diameters. Replace with something.

That is, in this conventional combustion flow control device, the adjusting screw 12 of the adjusting mechanism 13 is used in order to regulate the minimum gas flow that stably burns without causing blowout or the like in the burner 9 due to the influence of wind. The gap between the valve element 6 and the valve seat 7 is individually mechanically adjusted by using the switch of the control mechanism 13 for the control current range of the control circuit for gas groups having different heat generation values and supply pressures. Therefore, the maximum gas flow rate is also regulated.

[0007]

However, the above-mentioned conventional configuration has the following problems.

For example, a configuration in which the gap between the valve element 6 and the valve seat 7 is controlled by controlling the current of a solenoid actuator to control the gas flow rate is a well-known force generated in the plunger 5 with respect to the current of the electromagnetic coil 4. In addition, since the displacement of the valve element 6 causes a relatively large hysteresis and a large variation in characteristics, it is actually difficult to accurately control the combustion amount, and cannot be used for, for example, thermal power control by open control of a gas table. Was something.

Moreover, it has been difficult to accurately set and control the amount of combustion with reproducibility at a small resolution.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems. It is a first object of the present invention to provide a combustion amount control device capable of accurately setting and controlling the combustion amount with small resolution and good reproducibility. I have.

A second object of the present invention is to enable a position sensor to detect the position of the stepping motor at which the valve element can be reliably closed, and to apply a quantitative pulse to the stepping motor from the closed position to a predetermined heating power. It is another object of the present invention to provide a combustion amount control device which operates so as to be able to reproduce with high precision, can control the thermal power accurately, quickly and with good reproducibility, and can finely control the combustion flow rate by closing and fully opening with one valve device.

A third object of the present invention is to provide a combustion amount control device capable of performing safer and more reliable combustion amount control even when a stepping motor loses a certain number of pulses during operation. is there.

[0013]

In order to achieve the first object, a combustion control apparatus according to the present invention comprises a valve provided between an inlet and an outlet, a stepping motor for driving the valve, , A burner for burning the fuel sent from the outlet, and a control unit for controlling the stepping motor to control the thermal power.

According to another aspect of the present invention, there is provided a combustion amount control device, comprising: a valve body provided between an inlet and an outlet; and a stepping motor for driving the valve body. A burner that burns the fuel sent from the outlet, a control unit that controls the stepping motor to control the heating power, and a position sensor that detects a position of the stepping motor from a closed position of the valve element to a predetermined heating power. It is provided with.

According to a third aspect of the present invention, there is provided a combustion amount control apparatus comprising: a variable fuel supply device comprising a valve body provided between an inlet and an outlet, and a stepping motor for driving the valve body. A burner that burns the fuel sent from the outlet, a control unit that controls the stepping motor to control the heating power, and a position sensor that detects a position of the stepping motor from a closed position of the valve element to a predetermined heating power. Wherein the position sensor is a combustion amount control device provided on a shaft driven by the stepping motor and interlocked with the valve element.

In the combustion amount control apparatus of the present invention, the control section sends an application pulse to a stepping motor for driving a valve element provided between the inlet and the outlet, thereby achieving reproducibility with a small resolution. It works to set and control the amount of combustion well and accurately.

Further, according to the combustion amount control device of the present invention, the position sensor for detecting the position of the stepping motor from the closed position of the valve element to a predetermined heating power by the above-described configuration allows the combustion power to be controlled from the closing position of the valve element to the predetermined heating power. The pulse applied to the stepping motor acts so that it can be reproduced quantitatively and with high precision, and the thermal power can be controlled accurately, quickly and with good reproducibility, and the combustion flow rate can be controlled finely from a closed state to a fully opened state with a single valve device. Works.

Further, the combustion amount control device of the present invention has a position sensor provided on a shaft driven by the stepping motor and interlocked with the valve element, so that the stepping motor loses some pulses during operation. Even if such a situation occurs, the position sensor can detect the position of the valve body in conjunction with the valve body, and acts to more safely and reliably control the combustion flow rate.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. First, in FIG. 1, a fuel supply variable device 24 having a fuel inlet 22 and an outlet 23, a burner 25 for burning the fuel sent from the outlet 23, a flame sensor 26 for converting the flame of the burner 25 into an electric signal, A flame signal storage unit 27 that stores a signal of the flame sensor 26, a flame signal storage instruction unit 28 that instructs the flame signal storage unit 27 to store a signal of the flame sensor 26 by a switch operation, and a storage signal of the flame signal storage unit 27. A flame signal comparison / determination unit 29 that compares and determines a signal from the flame sensor 26 and an operation signal transmission unit 30 that transmits an operation signal to the fuel supply variable device 24 based on at least the determination result of the flame signal comparison / determination unit 29 are provided. Configuration.

Next, the operation and operation of the above embodiment will be described. First, the burner 25 is connected via the fuel supply varying device 24.
The fuel sent to is burned by the burner 25 and the flame sensor 26 converts the fuel signal into an electric signal corresponding to the size of the flame 31 burned by the burner 25. That is, a flame signal is emitted from the flame sensor 26 in accordance with the amount of combustion. The flame signal is sent to the control unit 32. By operating a switch 33 (not shown) of the flame signal storage instruction unit 28 provided in the control unit 32, the flame signal is transmitted to the control unit 32.
Is stored in the flame signal storage unit 27.

For example, when the switch 33 of the flame signal storage instructing unit 28 is operated at the time of the combustion of the heating power 1, the flame signal of the combustion amount of the heating power 1 is stored. By operating the switch, a flame signal of the combustion amount of the thermal power 2 is stored. Similarly, when the switch of the flame signal storage instructing unit 28 is operated at the time of the combustion amount of the thermal power 5, the flame signal of the combustion amount of the thermal power 5 is stored. In the state where the flame signals of the combustion amounts of the thermal power 1 to the thermal power 5 are stored in this manner, for example, when the thermal power 3 is instructed by the thermal power instruction unit 34 (not shown) of the control unit 32, the flame sensor 26 outputs While the control unit 32 receives the flame signal, the flame signal comparison / determination unit 29 of the control unit 32 compares the signal stored in the flame signal storage unit 27 with the signal from the flame sensor 26, and the stored fire power 3 The operation signal sending unit 30 sends an operation signal to the fuel supply variable device 24 so as to maintain a state of the combustion amount of the heating power 3 so that a flame signal corresponding to the combustion amount is obtained.

Conventionally, at the time of manufacturing, a mechanical adjustment operation such as individually adjusting the gap between the valve body 6 and the valve seat 7 with the adjusting screw 12 of the adjusting mechanism 13 of the proportional control valve 8 is required, Tightening the lock nut so that it does not shift after adjustment, and further adjusting the control gain with the knob of the variable resistor of the control unit 18 to cover the variation in the gain of the flow rate characteristic of the proportional control valve 8. It required time-consuming work.

On the other hand, in the present embodiment, the thermal power to be stored, that is, the amount of combustion,
While monitoring and checking the nozzle pressure of the burner nozzle 35 while varying the combustion amount in 4, just press the button switch of the flame signal storage instructing unit 28 when the predetermined pressure is reached.
Since the flame signal from the flame sensor 26 at the predetermined thermal power is stored in the flame signal storage unit 27, the stored thermal power can be stored at any time regardless of the characteristic variation in the fuel supply variable device 24 or the flame sensor 26. Can be reproduced.

That is, at the time of manufacture, the flame signal storage instructing section 28
It is possible to realize a combustion amount control device that does not require a mechanical adjustment operation only by operating the switch.

Therefore, it is possible to make it easier to manage the characteristic variation of the functional components such as the variable fuel supply device 24 and the flame sensor 26, to simplify the manufacturing work and to reduce the number of steps.

FIG. 2 shows a second embodiment. The combustion amount control device of the embodiment shown in FIG. 2 includes a fuel supply variable device 24 having a fuel inlet 22 and an outlet 23, a burner 25 for burning fuel sent from the outlet 23, and a flame 31 of the burner 25 as an electric signal. And a minimum flame signal storage unit 3 for storing at least the minimum flame signal of the flame sensor 26
6, a flame signal storage instructing unit 28 for instructing the minimum flame signal storage unit 36 to store at least the minimum flame signal of the flame sensor 26 by a switch operation, and a storage signal of the minimum flame signal storage unit 36 and a signal from the flame sensor 26. A flame signal comparison / determination unit 29 for comparing and distinguishing between the two, and an operation signal transmission unit 30 for transmitting an operation signal to the fuel supply variable device 24 based on at least the determination result of the flame signal comparison / determination unit 29 are provided.

Next, the operation and operation of the above embodiment will be described. First, the burner 25 is connected via the fuel supply varying device 24.
The fuel sent to is burned by the burner 25 and the flame sensor 26 converts the fuel signal into an electric signal corresponding to the size of the flame 31 burned by the burner 25. That is, a flame signal is emitted from the flame sensor 26 in accordance with the amount of combustion. The flame signal is sent to the control unit 32. By operating a switch 33 (not shown) of the flame signal storage instruction unit 28 provided in the control unit 32, the flame signal is transmitted to the control unit 32.
Is stored in the minimum flame signal storage unit 36.

For example, when the switch 33 of the flame signal storage instructing unit 28 is operated at the time of the minimum combustion amount, the flame signal of the minimum combustion amount is stored. In the case where the flame signal of the minimum combustion amount is stored in this way and, for example, the combustion amount is controlled while feeding back the temperature of the non-heated material, the control unit 32 receives the flame signal from the flame sensor 26 and performs the control. Part 32
The flame signal comparison / determination section 29 compares the signal stored in the minimum flame signal storage section 36 with the signal from the flame sensor 26, and burns with a combustion amount smaller than the flame signal corresponding to the already stored minimum combustion amount. The operation signal transmitting section 30 operates to transmit an operation signal to the fuel supply variable device 24 so that the operation signal does not exist.

Conventionally, at the time of manufacturing or gas type conversion, the regulating mechanism of the proportional control valve 8 is used to regulate the minimum gas flow rate for stably burning without, for example, blowing out by the effect of the wind in the burner 9. 13 requires a mechanical adjustment operation such as individually adjusting the clearance between the valve element 6 and the valve seat 7 with the adjustment screw 12, and tightening a lock nut so as not to slip after the adjustment. It required a lot of work.

On the other hand, in the present embodiment, the minimum heating power to be stored, that is, the minimum combustion amount, is determined by monitoring the nozzle pressure of the burner nozzle 35 while monitoring the nozzle pressure of the burner nozzle 35 while varying the combustion amount by, for example, the variable fuel supply device 24. By simply pressing the button switch of the flame signal storage instructing unit 28 when the pressure reaches the pressure, the flame sensor 26 at the predetermined minimum heating power
Is stored in the minimum flame signal storage unit 36, for example, the fuel supply variable device 24 or the flame sensor 26.
Irrespective of the characteristic variation, the stored minimum combustion state can be detected.

That is, a combustion amount control device capable of regulating and controlling the minimum combustion amount without the need for mechanical adjustment work, with only the operation of operating the switch of the flame signal storage instructing unit 28 during production and gas type conversion. Can be realized.

Therefore, it is possible to roughly manage the characteristic variation of the functional components such as the variable fuel supply device 24 and the flame sensor 26, and to simplify the operation at the time of manufacturing and gas type conversion and to prevent the burner from misfiring. A simple combustion amount control device can be realized.

FIG. 3 shows a third embodiment. The combustion amount control device of the embodiment shown in FIG. 3 includes a fuel supply variable device 24 having a fuel inlet 22 and an outlet 23, a burner 25 for burning fuel sent from the outlet 23, and a flame 31 of the burner 25 as an electric signal. A minimum flame signal and a maximum flame signal storage unit 37 for storing at least the minimum flame signal and the maximum flame signal of the flame sensor 26, and at least the minimum flame signal and the maximum flame signal of the flame sensor 26 by the switch operation. The flame signal storage instructing unit 28 for instructing the storage of the maximum to maximum flame signal storage unit 37, and the minimum to maximum flame signal storage unit 3
7 and a signal from the flame sensor 26, and an operation signal sending unit that sends an operation signal to the fuel supply variable device 24 based on at least the judgment result of the flame signal comparison and judgment unit 29. 30 is provided.

Next, the operation and operation of the above embodiment will be described. First, the burner 25 is connected via the fuel supply varying device 24.
The fuel sent to is burned by the burner 25 and the flame sensor 26 converts the fuel signal into an electric signal corresponding to the size of the flame 31 burned by the burner 25. That is, a flame signal is emitted from the flame sensor 26 in accordance with the amount of combustion. The flame signal is sent to the control unit 32. By operating a switch 33 (not shown) of the flame signal storage instruction unit 28 provided in the control unit 32, the flame signal is transmitted to the control unit 32.
Is stored in the minimum to maximum flame signal storage unit 37. For example, when the combustion amount is the minimum, the switch 3 of the flame signal
3 is operated, the flame signal of the minimum combustion amount is stored.
By operating 3, the flame signal of the maximum combustion amount is stored. In the case where the flame signal of the minimum and maximum combustion amounts is stored in this way and, for example, the combustion amount is controlled while feeding back the temperature of the non-heated object, the control unit 32 receives the flame signal from the flame sensor 26 while receiving the flame signal. The flame signal comparison / determination section 29 of the control section 32 compares the stored signal of the minimum to maximum flame signal storage section 37 with the signal from the flame sensor 26, and outputs the flame corresponding to the already stored minimum combustion amount and maximum combustion amount. The operation signal sending section 30 operates to send an operation signal to the fuel supply variable device 24 so as not to deviate from the range of the signal. Therefore, even when the pressure of the fuel supply source fluctuates, the fuel supply variable device 24 is controlled so as not to deviate from the range of the minimum to maximum combustion amount.

Conventionally, if the supply gas pressure fluctuates, for example, even if the minimum gap between the valve element 6 and the valve seat 7 can be made constant, the fluctuation of the minimum gas flow rate cannot be prevented. I couldn't omit it.

On the other hand, in this embodiment, the minimum
Since the maximum flame signal storage unit 37 can store the flame signals of the minimum and maximum combustion amounts, and the control unit 32 receives the flame signal from the flame sensor 26 and controls the fuel supply variable device 24, for example, the fuel supply source Even if the pressure fluctuates, the combustion amount can be controlled so as not to deviate from the minimum combustion amount and the maximum combustion amount.

Therefore, the governor 3 for stabilizing the fuel supply pressure can be dispensed with, and the configuration of the combustion amount control device can be simplified.

FIG. 4 shows a fourth embodiment. The combustion amount control device of the embodiment shown in FIG. 4 includes a fuel supply variable device 24 having a gas inlet 22 and an outlet 23, a burner 25 for burning gas sent from the outlet 23, and a flame 31 of the burner 25. A flame sensor 26 that converts the flame signal into a flame signal, a type flame signal storage unit 38 that stores at least a minimum flame signal and a maximum flame signal of the flame sensor 26 for each gas type group, and a gas flame that converts at least the minimum flame signal and the maximum flame signal of the flame sensor 26 into gas. A flame signal storage instructing unit 28 for storing and instructing the type flame signal storage unit 38 by a switch operation for each type group, a gas type group changeover switch 39, a storage signal of the type flame signal storage unit 38, and a signal from the flame sensor 26. Signal comparing and judging unit 29 for comparing and judging the fuel supply variable device 24 based on at least the judgment result of the flame signal comparing and judging unit 29. Operation signal is a configuration in which an operation signal sending unit 30 for sending the.

Next, the operation and operation of the above embodiment will be described. First, the burner 25 is connected via the fuel supply varying device 24.
The gas sent to is burned by the burner 25, and the flame sensor 26 converts the gas into an electric signal corresponding to the size of the flame 31 burned by the burner 25. That is, a flame signal is issued from the flame sensor 26 in accordance with the gas combustion amount. The flame signal is sent to the control unit 32, and by operating a switch 33 (not shown) of the flame signal storage instruction unit 28 provided in the control unit 32, the flame signal is transmitted to the type flame of the control unit 32. It is stored in the signal storage unit 38. For example, when the gas type group changeover switch 39 is set to the applicable gas type group and the switch 33 of the flame signal storage instructing unit 28 is operated at the time of the minimum combustion amount, the flame signal of the minimum combustion amount of the gas type is stored, and the maximum. If the switch 33 of the flame signal storage instruction section 28 is operated at the time of the combustion amount, the flame signal of the maximum combustion amount is stored. In the case where the flame signal of the minimum and maximum combustion amount of each gas type is stored and the switch 39 is switched to the gas type group to be used, for example, when the combustion amount is controlled while feeding back the temperature of the non-heated material, the flame While the control unit 32 receives the flame signal from the sensor 26, the flame signal comparison / determination unit 29 of the control unit 32 compares the storage signal of the type flame signal storage unit 38 with the signal from the flame sensor 26, and stores the flame signal. The operation signal transmitting section 30 operates to transmit an operation signal to the fuel supply variable device 24 so as not to deviate from the range of the flame signal corresponding to the minimum combustion amount and the maximum combustion amount of the gas type group. Therefore, even when the gas pressure of the gas supply source fluctuates, the fuel supply variable device 24 is controlled so as not to deviate from the range of the minimum to maximum combustion amount.

Conventionally, for example, at the time of gas type conversion, the range of the control current of the proportional control valve 8 is switched by a changeover switch of the changeover mechanism 21 and, in some cases, the valve body 6 and the valve seat 7 are replaced with those having appropriate diameters. However, since the variation in the flow characteristics with respect to the control current of the proportional control valve 8 is large, it is actually difficult to manage the characteristics of the proportional control valve 8 and not only switch the switching mechanism 21 but also change the gas type. Occasionally, the current adjustment work of the control circuit was required. Moreover, in order to regulate the minimum gas flow, the adjusting screw 12 of the adjusting mechanism 13 is used.
Accordingly, the operation of individually mechanically adjusting the gap between the valve element 6 and the valve seat 7 has also been required.

On the other hand, in the present embodiment, only by switching the gas type group using the changeover switch 39, the flame signal of the gas type group stored in the type flame signal storage unit 38 and the flame sensor 26 are used. The control unit 32 controls the fuel supply variable device 24 so as not to deviate from the combustion range of the minimum combustion amount and the maximum combustion amount of the gas type group while comparing the flame signal of Simple and safe gas conversion can be realized without electric circuit adjustment and mechanical adjustment work.

A fifth embodiment will be described with reference to FIG. Fifth
The combustion amount control device according to the embodiment includes a valve seat 40 provided between the inlet 22 and the outlet 23, and a valve body 4 provided opposite the valve seat 40.
1, a fuel supply variable device 24 comprising a stepping motor 42 for driving a valve element 41, a burner 25 for burning the fuel sent from the outlet 23, and a flame sensor 26 for converting the flame 31 of the burner 25 into an electric signal. And the flame sensor 26
Signal storage unit 27 for storing the signal of
A flame signal storage instructing unit 28 for storing and instructing the signal of No. 6 in the flame signal storage unit 27 by a switch operation, and a flame signal comparison and determination unit 29 for comparing and determining the storage signal of the flame signal storage unit 27 and the signal from the flame sensor 26. And at least the fuel supply variable device 24 based on the determination result of the flame signal comparison determination unit 29.
And an operation signal transmission unit 30 for transmitting an operation signal.

Next, the operation and operation of the above embodiment will be described. First, a valve seat 40 provided between the inlet 22 and the outlet 23
Burner 2 via a variable fuel supply device 24 comprising a stepping motor 42 for driving a valve element 41 provided opposite to the burner 2.
The fuel sent to 5 is burned by the burner 25 and is converted by the flame sensor 26 into an electric signal corresponding to the size of the flame 31 burned by the burner 25. That is, a flame signal is emitted from the flame sensor 26 in accordance with the amount of combustion. The flame signal is sent to the control unit 32. By operating a switch 33 (not shown) of the flame signal storage instruction unit 28 provided in the control unit 32, the flame signal is transmitted to the control unit 32.
Is stored in the flame signal storage unit 27. For example, when the switch 33 of the flame signal storage instructing unit 28 is operated at the time of the combustion amount of the heating power 1, the flame signal of the combustion amount of the heating power 1 is stored. If operated, the flame signal of the combustion amount of the thermal power 2 is stored. Similarly, when the combustion amount of the thermal power 5 is reached, the flame signal storage instructing unit 2
By operating the switch 33 of No. 8, the flame signal of the combustion amount of the heating power 5 is stored. In the state where the flame signals of the combustion amounts of the thermal power 1 to the thermal power 5 are stored in this manner, for example, when the thermal power 3 is instructed by the thermal power instruction unit 34 (not shown) of the control unit 32, the flame sensor 26 outputs While the control unit 32 receives the flame signal, the flame signal comparison / determination unit 29 of the control unit 32 compares the signal stored in the flame signal storage unit 27 with the signal from the flame sensor 26, and the stored fire power 3 The operation signal sending section 30 sends an operation signal to the stepping motor 42 of the fuel supply variable device 24 so that the flame signal corresponding to the combustion amount is obtained, so that the combustion amount of the heating power 3 is accurately maintained with fine resolution. Works.

Conventionally, the gap between the valve body 6 and the valve seat 7 is adjusted by controlling the current of a solenoid actuator to control the gas flow rate. Since the displacement of the body 6 causes a relatively large hysteresis and a large variation in characteristics, it is actually difficult to accurately control the combustion amount, and cannot be used for, for example, thermal power control by open control of a gas table. there were. In addition, since the amount of combustion cannot be detected even when the temperature of the hot water is fed back, it has been difficult to set and control the amount of combustion accurately with good resolution and small reproducibility.

On the other hand, in the present embodiment, the flame signal from the flame sensor 26 at a predetermined thermal power can be stored in the flame signal storage section 27, and the valve seat 40 and the valve body 41
The stepping motor 42 allows the gap to be controlled accurately and in small increments according to the applied pulse, so that the combustion amount can be set and controlled accurately with small resolution and with good reproducibility.

A sixth embodiment will be described with reference to FIG. Sixth
In the combustion amount control device of the embodiment, the valve body 46 having the valve seat 40 between the inlet 22 and the outlet 23, the valve body 41 provided opposite the valve seat 40, and the valve body 41 A closing spring 43 for urging in a closing direction, a stepping motor 42 for driving a valve shaft 44 against the closing spring 43, and a valve body 41
The fuel supply variable device 24 includes a position sensor 45 that detects the position of a stepping motor 42 that reliably closes the valve seat 40, the burner 25 that burns fuel sent from the outlet 23, and the flame 31 of the burner 25. A flame sensor 26 that converts the signal into an electric signal, a flame signal storage unit 27 that stores the signal of the flame sensor 26, and a flame signal storage instruction unit 28 that stores the signal of the flame sensor 26 in the flame signal storage unit 27 by operating a switch. A flame signal comparison / determination unit 29 for comparing and distinguishing a signal stored in the flame signal storage unit 27 with a signal from the flame sensor 26; And an operation signal transmitting section 30 for performing the operation.

Next, the operation and operation of the above embodiment will be described. First, a valve seat 40 provided between the inlet 22 and the outlet 23
Through a variable fuel supply device 24 comprising a stepping motor 42 that drives a valve shaft 44 in a direction in which the valve body 41 opens and opens against a force of a closing spring 43 that urges the valve body 41 in a direction in which the valve body 41 closes. The fuel sent to the burner 25 burns at the burner 25 and the flame 3 burned at the burner 25.
The flame sensor 26 converts the electric signal into an electric signal corresponding to the value of “1”. That is, a flame signal is emitted from the flame sensor 26 in accordance with the amount of combustion. The flame signal is sent to the control unit 32. By operating a switch 33 (not shown) of the flame signal storage instruction unit 28 provided in the control unit 32, the flame signal is transmitted to the control unit 32. It is stored in the storage unit 27. For example, at the time of the combustion amount of the thermal power 1, the flame signal storage instructing unit 2
When the switch 33 of the firepower 2 is operated, the flame signal of the combustion amount of the heating power 1 is stored. When the switch 33 of the flame signal storage instructing section 28 is operated at the time of the combustion amount of the heating power 2, the flame signal of the combustion amount of the heating power 2 is stored. Is done. Similarly, when the switch 33 of the flame signal storage instructing unit 28 is operated at the time of the combustion amount of the thermal power 5, the flame signal of the combustion amount of the thermal power 5 is stored. In a state where the flame signals of the combustion amounts of the thermal power 1 to the thermal power 5 are stored in this manner, for example, when the thermal power 3 is instructed by the thermal power instruction unit 34 (not shown) of the control unit 32, the flame sensor 26 outputs While the control unit 32 receives the flame signal, the flame signal comparison / determination unit 29 of the control unit 32 compares the signal stored in the flame signal storage unit 27 with the signal from the flame sensor 26, and the stored fire power 3 The operation signal sending unit 30 sends an operation signal to the stepping motor 42 of the variable fuel supply device so that the flame signal corresponding to the combustion amount is obtained, and the operation signal sending unit 30 operates so as to accurately maintain the combustion amount state of the thermal power 3 with fine resolution. I do. In addition, the position sensor 45 can detect the position of the stepping motor 42 at which the valve element 41 can reliably close the valve seat 40, and the pulse applied to the stepping motor 42 from the closed position to a predetermined heating power is quantitative and high. It works so that it can be reproduced with high accuracy, and it can control the heat power accurately, quickly and with good reproducibility, and also works to finely control the combustion flow rate by closing or fully opening with one valve device.

Since the seal member between the valve shaft 44 and the valve body 46 is constituted by the diaphragm 47, the seal member is sealed with an O-ring, for example, so that the valve shaft 44 must slide. In contrast, since there is no sliding friction, the force of the closing spring 43 can be utilized only for the valve body 41 to close the valve seat 40 effectively. Therefore, even if the biasing force of the closing spring 43 is relatively small, the closing can be sufficiently performed, and the valve shaft 4 can be closed.
The stepping motor 42 for operating the valve element 41 by pushing the 4 with the eccentric cam 48 can be a small-sized stepping motor with low torque.

The position sensor 45 is an encoder linked to the rotation of the cam shaft 49 of the eccentric cam 48. The position sensor 45 can send a closing position signal to the control unit 32 at a position where the valve body 41 reliably closes the valve seat 40. Therefore, even if the stepping motor 42 loses synchronism by a few pulses during operation, it can be surely confirmed whether the stepping motor 42 is in the closed position.
When the control unit 32 receives the closing position signal, the number of pulses to the stepping motor 42 can be reset to zero,
Safer and more reliable combustion amount control can be performed.

The flame sensor 26 converts the amount of heat received from the flame 31 into an electric signal according to the amount of combustion of the burner 25. In this embodiment, the flame sensor 26 is constituted by a thermoelectric element. It may be something.

Conventionally, for example, the proportional control valve 8 does not have a closing function and requires a separate closing valve 2. If the safety function requires a double closing function, another closing valve is attached. It was indispensable, and it was also a problem in terms of downsizing of equipment and assembly man-hours.

On the other hand, in this embodiment, the valve body 4
1 is a stepping motor 4 that can securely close the valve seat 40
With the configuration that the position 2 can be reliably detected by the position sensor 45,
Since the flame signal from the flame sensor 26 at a predetermined thermal power can be stored in the flame signal storage unit 27, and the gap between the valve seat 40 and the valve body 41 can be accurately and minutely controlled by the stepping motor 42 according to the applied pulse. ,
With one valve device, the combustion amount can be accurately set and controlled with a small resolution from close to full open with good reproducibility.

[0053]

As described above, according to the combustion amount control device of the present invention, the following effects can be obtained.

(1) A variable fuel supply device comprising a valve provided between an inlet and an outlet, a stepping motor for driving the valve, a burner for burning fuel sent from the outlet, and the stepping Since the configuration includes the control unit for controlling the motor and controlling the thermal power, it is possible to realize a combustion amount control device capable of accurately setting and controlling the combustion amount with small resolution and with good reproducibility.

(2) A variable fuel supply device comprising a valve provided between an inlet and an outlet, a stepping motor for driving the valve, a burner for burning fuel sent from the outlet, and the stepping A control unit that controls the heating power by controlling the motor, and a position sensor that detects the position of the stepping motor from a closed position of the valve body to a predetermined heating power, so that the stepping motor of the valve body that can be reliably closed. The position can be detected by the position sensor, and the applied pulse to the stepping motor from the closed position to the predetermined heating power can be reproduced quantitatively and with high accuracy, and the heating power can be accurately, quickly and reproducibly controlled, A combustion amount control device capable of finely controlling the combustion flow rate from a closed state to a fully opened state with one valve device can be realized.

(3) A variable fuel supply device comprising a valve element provided between an inlet and an outlet, a stepping motor for driving the valve element, a burner for burning the fuel sent from the outlet, and the stepping A control unit for controlling a heat power by controlling a motor, and a position sensor for detecting a position of the stepping motor from a closed position of the valve body to a predetermined heat power, wherein the position sensor is driven by the stepping motor and the valve Even if the stepping motor provided on the shaft linked to the body loses some pulses during operation, it is possible to obtain a combustion amount control device capable of performing safer and more reliable combustion amount control.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a combustion amount control device according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a combustion amount control device according to another embodiment.

FIG. 3 is a schematic configuration diagram of a combustion amount control device in another embodiment.

FIG. 4 is a schematic configuration diagram of a combustion amount control device in another embodiment.

FIG. 5 is a schematic configuration diagram of a conventional combustion amount control device.

[Explanation of symbols]

 Reference Signs List 22 Inlet 23 Outlet 24 Fuel supply variable device 25 Burner 26 Flame sensor 27 Flame signal storage unit 28 Flame signal storage instructing unit 29 Flame signal comparison / determination unit 30 Operation signal sending unit 36 Minimum flame signal storage unit 37 Minimum to maximum flame signal storage unit 38 type flame signal storage unit 39 changeover switch 40 valve seat 41 valve body 42 stepping motor 43 closing spring 44 valve shaft 45 position sensor 46 valve body

Claims (3)

[Claims] 1. A fuel supply variable device comprising a valve body provided between an inlet and an outlet, a stepping motor for driving the valve body, a burner for burning fuel sent from the outlet, and the stepping motor. And a control unit for controlling thermal power by controlling the combustion amount. 2. A fuel supply variable device comprising a valve provided between an inlet and an outlet, a stepping motor for driving the valve, a burner burning fuel sent from the outlet, and the stepping motor. And a position sensor for detecting a position of the stepping motor from a closed position of the valve element to a predetermined heating power. 3. A variable fuel supply device comprising a valve body provided between an inlet and an outlet, a stepping motor for driving the valve body, a burner for burning fuel sent from the outlet, and the stepping motor. And a position sensor for detecting the position of the stepping motor from a closed position of the valve body to a predetermined heating power, wherein the position sensor is driven by the stepping motor and the valve body A combustion amount control device provided on a shaft that works in conjunction with.