JP2009210183A - Water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To adjust the air fuel ratio of air to gas to substantially meet an ideal, and to eliminate the need of the specialist's adjusting of a water heater according to gas pressure at a construction job site. <P>SOLUTION: This water heater 1 is a device for heating a heat exchanger 4 in a combustion part 2 to convert water to hot water. The water heater includes: a fan 3 for supplying air to the combustion part 2; a state signal detecting means 30 for detecting a driving state signal of a fan motor 3m; a gas flow control valve 6 for controlling the flow Q of gas supplied to the combustion part 2; a gas flow sensor 9 for detecting the flow Q of gas supplied to the combustion part 2; and an air fuel ratio control means 50 for obtaining, as an air fuel ratio, the ratio of an air flow A obtained from the driving state signal S detected by the state signal detecting means 30 to the gas flow Q detected by the gas flow sensor 9, and adjusting a valve opening of the gas flow control valve 6 to control the air fuel ratio R to a predetermined range when the air fuel ratio R is not within a predetermined range. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a hot water supply apparatus that heats a heat exchanger supplied with water in a combustion section to convert it into hot water.

As a method for adjusting the combustion state of the hot water supply device, it is possible to determine the amount of air sent to the combustion unit based on information such as the rotational speed and current value of the fan motor for sending air to the combustion unit and adjust the combustion state. It is general (see Patent Document 1 below).
JP 2002-333130 A

  On the other hand, the amount of gas sent to the combustion section may fluctuate due to fluctuations in the outside air temperature, etc.If the amount of gas fluctuates even if only the amount of air is accurately controlled, accurate adjustment of the air-fuel ratio is not possible. The situation is not complete.

  In addition, in the construction of the hot water supply apparatus, it is necessary to adjust the equipment in accordance with the gas pressure applied to the hot water supply apparatus.

  This invention has been proposed in view of the above, and can adjust the air-fuel ratio of air and gas to a more ideal one, and does not require equipment adjustment according to the gas pressure by a specialist at the construction site. An object of the present invention is to provide a hot water supply device that can be used.

  In order to achieve the above object, the invention according to claim 1 is a hot water supply apparatus that heats a heat exchanger in a combustion section to convert water into hot water and supplies the heat to the combustion section. State signal detection means for detecting a driving state signal of a fan motor for driving the fan, a gas flow rate control valve for controlling a flow rate of gas supplied to the combustion unit, and a flow rate of gas supplied to the combustion unit. The ratio of the gas flow sensor to be detected, the air flow rate obtained from the driving state signal detected by the state signal detection means, and the gas flow rate detected by the gas flow sensor is obtained as an air-fuel ratio, and the air-fuel ratio is within a predetermined range. If not, air-fuel ratio control means for adjusting the valve opening degree of the gas flow control valve to control the air-fuel ratio to a predetermined range is provided.

  According to a second aspect of the present invention, in the first aspect of the present invention, when the gas flow rate detected by the gas flow sensor is outside a predetermined gas flow rate range set in advance, it is determined that there is an abnormality. An abnormality stop means for stopping the drive is provided.

  The invention according to claim 3 is determined to be abnormal when the gas flow rate detected by the gas flow sensor is outside a predetermined gas flow rate range set in advance in the invention according to claim 1 or 2, The abnormality of the gas flow rate is reported.

  According to a fourth aspect of the invention, in the first aspect of the invention described in any one of the first to third aspects, the state signal detecting means detects the rotational speed or driving current of the fan motor as a driving state signal. It is a thing.

  In the hot water supply apparatus of the present invention, the ratio of the air flow rate obtained from the drive state signal detected by the state signal detection means and the gas flow rate detected by the gas flow sensor is obtained as an air-fuel ratio, and the air-fuel ratio is not within a predetermined range. Since the air-fuel ratio is controlled within a predetermined range by adjusting the valve opening of the gas flow control valve, the air-fuel ratio of air and gas is adjusted to a more ideal one and the combustion state is always controlled well. In addition, it is unnecessary to adjust the apparatus according to the gas pressure by a specialist at the construction site.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a hot water supply apparatus of the present invention. In FIG. 1, a hot water supply apparatus 1 according to the present invention is an apparatus that heats a heat exchanger 4 in a combustion unit 2 to convert water into hot water and supplies it. A fan 3 that supplies air to the combustion unit 2, and a fan 3 A state signal detecting means 30 for detecting a driving state signal of the fan motor 3m for driving the gas, a gas flow rate control valve 6 for controlling the flow rate Q of the gas supplied to the combustion unit 2, and the gas supplied to the combustion unit 2 The ratio of the gas flow sensor 9 that detects the flow rate Q, the air flow rate A obtained from the driving state signal S detected by the state signal detection means 30 and the gas flow rate Q detected by the gas flow sensor 9 is the air-fuel ratio R (= A / Q), and when the air-fuel ratio R is not within the predetermined range, the air-fuel ratio control means 50 is provided for adjusting the valve opening degree of the gas flow rate control valve 6 to control the air-fuel ratio R to the predetermined range. ing.

  Further, an abnormality stop means 51 is provided, and when the gas flow rate Q detected by the gas flow sensor 9 is outside a predetermined gas flow rate range set in advance, it is determined that there is an abnormality and the driving of the apparatus 1 is stopped.

  The air-fuel ratio control means 50 and the abnormality stop means 51 are provided in the control unit 5. The control unit 5 is configured with a microcomputer (microcomputer) including a CPU, a ROM, and a RAM as a center, and controls the overall operation of the hot water supply device 1.

  The control unit 5 is connected to a remote controller (remote controller) 10 by a wiring cord or wirelessly, and can operate the hot water supply apparatus 1 from a remote place by operating an operation button of the remote controller 10.

  The heat generated by the combustion of the combustion unit 2 heats the water in the heat exchanger 4 to convert it into hot water, and the exhaust gas generated by the combustion is discharged from the exhaust port 7.

  The state signal detection means 30 includes a sensor that detects the rotational speed of the fan motor 3m. Therefore, the driving state signal S is a signal indicating the rotational speed of the fan motor 3m here. The driving state signal S may be a signal other than the motor rotation speed. For example, the driving current of the fan motor 3m may be used as the driving state signal S. This drive state signal S is sent to the air-fuel ratio control means 50 of the control unit 5.

  The gas flow control valve 6 and the gas flow sensor 9 are provided in a gas pipe 80 between the gas supply port 8 and the combustion unit 2. The gas flow rate control valve 6 is an electromagnetic proportional valve, and the valve opening degree is opened and closed according to a signal from the control unit 5 to control the supply gas flow rate. The gas flow sensor 9 is of a type that obtains the gas flow rate from a change in the resistance value of the heater caused by the gas flow, for example, and the detected change amount of the resistance value is sent to the control unit 5.

  The air-fuel ratio control means 50 is configured including a software function that is executed by the CPU according to a program, and performs a control operation according to the present invention. In other words, the air flow rate A is obtained from the drive state signal S using the graph showing the relationship between the drive state signal S and the air flow rate A, which is stored in advance in the ROM, and the data sent from the gas flow sensor 9. Based on the above, the gas flow rate Q is obtained. Then, as described above, the ratio of the air flow rate A and the gas flow rate Q is obtained as an air-fuel ratio R (= A / Q), and when the air-fuel ratio R is not within a predetermined range, the valve of the gas flow control valve 6 The opening degree is adjusted so that the air-fuel ratio R falls within a predetermined range. By this air-fuel ratio control, the combustion in the combustion section 2 is always maintained in an optimal combustion state.

  Similarly to the air-fuel ratio control means 50, the abnormal time stop means 51 is configured to include a software function that is executed by the CPU according to a program. As described above, the predetermined gas flow rate Q is preset. If the gas flow rate is out of the range and the gas flow rate is abnormally large or abnormally small, it is determined that the gas flow rate is abnormal, the control for stopping the combustion, for example, the gas flow control valve 6 is closed, and the fan motor 3m is rotated. Control to stop.

  Data of the predetermined gas flow rate range at this time is sent from the remote controller 10 to the control unit 5 in advance and stored in a nonvolatile storage device incorporated in the control unit 5.

  If the control unit 5 determines that the gas flow rate is abnormal, the control unit 5 outputs the gas flow rate abnormality to the remote controller 10 in parallel with or without stopping the combustion, and displays the LED on the remote controller 10. May be notified to the user.

  As described above, in the hot water supply apparatus 1 of the present invention, the ratio of the air flow rate A obtained from the drive state signal S detected by the state signal detection means 30 and the gas flow rate Q detected by the gas flow sensor 9 is determined as the air-fuel ratio. R (= A / Q) is obtained, and when the air-fuel ratio R is not within the predetermined range, the air-fuel ratio R is controlled within the predetermined range by adjusting the valve opening degree of the gas flow rate control valve 6. It is possible to adjust the air-fuel ratio of gas and gas to a more ideal one and to control the combustion state well at all times, and it is unnecessary to adjust the conventional equipment according to the gas pressure by the specialist at the construction site It can be.

  Further, when the gas flow rate Q detected by the gas flow sensor 9 is outside the predetermined gas flow rate range set in advance, it is determined that there is an abnormality and the drive of the device 1 is stopped or a notification to that effect is made. As a result, abnormal combustion can be reliably prevented, and the user can use it with peace of mind.

It is a schematic block diagram of the hot-water supply apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hot water supply apparatus 2 Combustion part 3 Fan 3m Fan motor 30 State signal detection means 4 Heat exchanger 5 Control part 6 Gas flow rate control valve 7 Exhaust port 8 Gas supply port 9 Gas flow sensor 10 Remote control 5 Control part 50 Air-fuel ratio control means 51 Stop means in case of abnormality 80 Gas piping A Air flow rate Q Gas flow rate R Air-fuel ratio S Drive status signal

Claims (4)

In a hot water supply apparatus that heats a heat exchanger in a combustion section to convert water into hot water and supply it,
A fan for supplying air to the combustion section;
State signal detecting means for detecting a driving state signal of a fan motor for driving the fan;
A gas flow control valve for controlling the flow rate of the gas supplied to the combustion section;
A gas flow sensor for detecting the flow rate of the gas supplied to the combustion section;
The ratio of the air flow rate obtained from the driving state signal detected by the state signal detection means and the gas flow rate detected by the gas flow sensor is obtained as an air-fuel ratio, and when the air-fuel ratio is not within a predetermined range, gas flow control is performed. Air-fuel ratio control means for adjusting the valve opening of the valve to control the air-fuel ratio to a predetermined range;
A hot water supply apparatus comprising:   The hot water supply apparatus according to claim 1, further comprising an abnormality stop unit that determines that the gas flow rate detected by the gas flow sensor is outside the predetermined gas flow rate range and determines that the gas flow sensor is abnormal and stops driving the apparatus.   3. The hot water supply apparatus according to claim 1, wherein when the gas flow rate detected by the gas flow sensor is outside a predetermined gas flow rate range set in advance, it is determined that there is an abnormality and the abnormality in the gas flow rate is reported.   The hot water supply apparatus according to any one of claims 1 to 3, wherein the state signal detection means detects the rotation speed or drive current of the fan motor as a drive state signal.

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