JPS62102026A - Combustion device - Google Patents

Abstract

PURPOSE:To control a rate of excessive air so as to show its constant value by a method wherein a combustion blower is driven by DC motor and an amount of combustion air is varied in response to a variation of the combustion volume. CONSTITUTION:When a power supply is turned on, a proportional valve 4 and a fan 5 are operated. A thermistor 2 detects a hot-water temperature of a hot-air temperature, indicates a resistance in response to the sensed temperature, then a proportional control circuit 3 and an air amount control circuit 8 are operated. Under an operation of the proportional control circuit 3, the proportional valve 4 may supply the specified amount of gas and then a combustion volume corresponding to a temperature of hot water or the like can be attained. Under an operation of the air amount control circuit 8, its control signal is received to operate the number of revolution control circuit 6, and the amount of air corresponding to the combustion volume responding to the temperature sensed by a thermistor 2 is supplied by a fan 5 by DC voltage applied to DC motor 5' through a driving circuit 7. With a provision of the DC motor, a control range for the number of revolution ranging from low speed revolution to high speed revolution can be attained, hand a pursuing characteristic is made fast and an amount of supplied air can be assured to keep an excessive rate of air for a high load combustion constant.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a combustion device for burning gas, oil, etc. in a water heater or hot air blower, in which combustion air is regulated by a fan.

(Prior Art) A conventional forced intake/exhaust type gas combustor is known in which the amount of combustion air is adjusted and controlled in synchronization with the fuel 11 supply valve while controlling it. (Jitsukai 1977 789
38＠＞(Problems to be solved by the invention) In the conventional type, high-speed rotation is required especially when performing high-load combustion, and when ignition or when the load capacity increases (
When the proportional valve opens rapidly, the follow-up characteristic of supplying combustion air is slow, causing incomplete combustion, and the purpose of this invention is to solve these problems.

(Means for Solving the Problems) The present invention includes a resistance circuit that detects the temperature of hot water, hot air, etc. and changes the resistance value, and a circuit that controls a fuel supply valve and a wind valve by the operation of this resistance circuit. In a combustion device that is equipped with a control circuit that controls the air volume of a combustion blower,
The combustion blower was configured to be driven by a DC motor.

(Function) In the present invention, a predetermined drive current is obtained by the rotation speed control circuit and the drive circuit via the AC-DC conversion circuit, and the rotation of the fan is ensured. The excess air ratio is controlled to be constant by changing the amount of air.

(Example) An embodiment of the present invention will be described in detail.

1. is the power supply to which ACloov is supplied; 2. 3. is a temperature sensor thermistor that detects hot water temperature, hot air temperature, etc.;
is a proportional control circuit that operates using the resistance-temperature characteristics of the thermistor 2, which controls the current supplied to the gas proportional valve 4 and controls the gas amount so that the hot water temperature and hot air temperature are constant. . 5. is a fan, and 5- is a DC motor. 6. 1 is a fan rotation speed control circuit that controls the DC motor 5- using the resistance-temperature characteristics of the thermistor 2, and is operated by being supplied with a control signal from the air volume control circuit 8.

When the power is turned on, the proportional valve 4 and fan 5 operate.

In this state, the thermistor 2 detects the hot water temperature or hot air temperature and exhibits resistance accordingly, thereby operating the proportional control circuits 3 and 3 and the Li control circuit 8. Through the operation of the proportional control circuit 3, the proportional valve 4 supplies a predetermined amount of gas to obtain a combustion amount corresponding to the temperature of the hot water or the like.

In addition, the rotation speed control circuit 6 is operated in response to the control signal received by the operation of the air volume control circuit 8, and the signal is applied to the DC motor 5- via the drive circuit 7 in accordance with the combustion amount according to the temperature detected by the thermistor 2. The dose is supplied by the fan 5 with a DC voltage. In FIG. 2, PS represents pressure (static pressure) and Q represents air pressure.

In order to increase the high pressure (PS) by 1q, the rotation speed must be increased, and with an AC motor, the rotation speed becomes constant and there is a limit to the high rotation speed, so a DC motor can handle this. I can do it.

As described above, since the combustion amount and IT are determined by detecting the temperature of hot water, etc., the air volume is variably supplied depending on the magnitude of the combustion amount, and an optimum combustion state is ensured. Since it is equipped with a DC motor, the rotation control range from low speed rotation to high speed rotation is wide (large variable range), and output increases by 50% to 60%, increasing efficiency. The rotation speed can be easily detected, for example, by converting the rotation speed into pulses using the output terminal signal from the Hall IC.
Since the rotational speed can be detected by detecting the rotational speed, by interposing the rotational speed detection circuit 10, the initial timing of ignition and the maintenance of a stable rotational speed can be improved.

(Effects of the Invention) The combustion air supply and gas supply of the present invention are controlled by a load signal such as a thermistor, and air volume control and proportional valve control are synchronized to perform high-load combustion. For operations with large load fluctuations, it is possible to ensure the supply air volume by quick follow-up performance, and it is also possible to maintain a constant excess air ratio in high-load combustion by being able to take out high-speed rotation and high pressure. Also, 60tlz, 50
There is no effect on Hz (conventional switching operations are not required). The acceleration of Fumon can enter the stable range within about 1 sec, which has the advantage of faster ignition time, and it also makes it possible to shorten purge time, which improves usability for the user. have

[Brief explanation of drawings]

FIG. 1 is a structural diagram of the present invention, FIG. 3 is a detailed explanatory diagram of the present invention, and FIG. 2 is a pressure-J! 1ffi is a relationship explanatory diagram. 1... Power supply 9... Water amount 2... Thermistor 10... Rotation speed detection circuit (temperature sensor) 11... Burner 3... Proportional control circuit 12... Heat exchanger 4.
... Proportional valve 13 ... Water supply pipe 5 ... Fan (DC motor) 14 ... Hot water pipe 6 ... Rotation speed control circuit A ... Control circuit 7 ... Drive circuit 8 ... Air volume control circuit

Claims (1)

[Claims] In a combustion device that compares and detects the temperature of hot water, hot air, etc. with a temperature sensor and controls the fuel supply valve based on the signal, as well as controlling the air volume of the combustion blower, the combustion blower is configured with a DC motor. A combustion device characterized by: