KR950000932B1 - Air heater - Google Patents

Abstract

The heater comprises a blower (3) sending the air to the room via the duct (3) for warm air; a combust ion duct (4) supplying the outdoor air and the fuel; a burner (6) heating the air which passes through the above duct (2); a control device (10) controlling the blower (3). The control device (10) has a device converting the level of combustion state, a device delaying the combustion, and a device controlling the quantity of the ventilation.

Description

Hot air heater

1 to 4 show one embodiment of the present invention.

1 is a schematic view showing a schematic structure of an FF gas hot air heater.

2 is a graph showing the relationship between the rate of change of the amount of gas and the rate of change of the blowing amount of the convection fan and time.

3 is a flowchart showing the main control of the microcomputer.

4 is a subroutine showing weak combustion control of the microcomputer 10.

* Explanation of symbols for main parts of the drawings

1: FF gas hot air heater 2: hot air duct

3: convection blower 6: gas burner (burner)

10: microcomputer (control circuit)

The present invention relates to a hot air heater in which the burned state of the burner can be switched to a plurality of stages.

Conventionally, the hot air heater which can switch the burner state of a burner into a strong combustion state and a weak combustion state, for example, an FF type petroleum hot air heater, is controlled. In this petroleum warm air heater, overheat safety devices such as thermal fuses or dummysters are provided to stop the burner when the temperature in the cabin rises above a predetermined value. In addition, the petroleum warm air heater switches the blowing amount of the convection fan from steel to weak when the burner combustion state is changed from the strong combustion state to the weak combustion state.

However, in the conventional petroleum warm air heater, the burner is operated for a long time in a strong combustion state, and the cabin temperature rises considerably and is stabilized. In such a case, if the airflow amount of the convection fan is synchronized with the combustion state and immediately switched from the strong wind amount to the weak air amount, the rising cabin temperature does not immediately decrease, and the cabin temperature further rises temporarily. As a result, electric devices such as control circuits and overheat safety devices installed in the cabin may malfunction.

In order to solve this problem, when switching the burner combustion state from the low combustion state to the low combustion state, the air flow of the convection fan is delayed by a certain time to a safe range in which the electric machine does not malfunction. You can buy a warm air heater.

By the way, when the burner is in a weakly burned state, the amount of air blown by the convection fan is preferable from the point of heating peeling, and keeping the amount of blown air of the convection fan by the strong wind amount for a predetermined time may be a possibility of cold air being blown out. Therefore, it is not preferable.

An object of the present invention is to provide a hot air heater capable of preventing malfunctions of control circuits or electrical equipment disposed in the cabin without disturbing the heating film.

The hot air heater of the present invention is a hot air duct for directing air to a room, a convection blower for generating an air flow toward the room within the hot air duct, and a combustion air to heat the air passing through the hot air duct. And a control means for controlling the convection blower in accordance with the combustion state of the burner, the control means being configured for the convection when the combustion state of the burner is changed from a strong combustion state to a weak combustion state. Technical means for switching from the strong wind amount to the weak air amount through a plurality of air volume steps while delaying the blow amount of the blower by a predetermined amount is adopted.

When the burner's combustion state is changed from the strong combustion state to the weak combustion state, the air flow amount is changed from the strong wind amount to the weak air amount through a plurality of air volume steps while delaying the blow amount of the convection blower by a predetermined time. For this reason, since the blowing amount of the convection blower is not maintained at the strong wind amount for a long time until it is switched from the strong wind amount to the weak air amount, it is avoided that the cool air is blown from the warm air duct toward the room.

In addition, when the combustion state of the burner is changed from the strong combustion state to the weak combustion state, since the convection blower does not immediately switch from the strong wind amount to the weak air amount, the cabin temperature is not set to a high temperature. For this reason, the malfunction of the electric equipments, such as a control circuit and overheating safety devices installed in the cabin, can be prevented.

Therefore, it is possible to reliably prevent malfunctions of electrical devices such as control circuits and overheat safety devices installed in the cabin without impeding heating peeling in the warm air heater.

The hot air heater of the present invention will be described based on the embodiment shown in FIGS.

1 shows a schematic structure of an FF gas hot air heater.

FF gas hot air heater (1) is a hot air duct (2), convection blower (3), combustion duct (4), combustion blower (5), gas burner (6), heat exchanger (61), combustion case 62 and the microcomputer 10 are provided.

The warm air duct 2 is a warm air passage which sucks indoor air from the inlet port 21 and blows out warm air from the blower port 22 toward the room. In addition, the inlet 21 is provided with a dummyster 11. The convection blower 3, the gas burner 6, the heat exchanger 61, the combustion case 62, and the overheat safety device 17 are provided inside the hot air duct 2.

The convection blower 3 has a convection fan 32 which is rotationally driven by an electric motor 31 whose rotational speed changes in accordance with the amount of energization, and generates an air flow in the warm air duct 2 toward the room.

The combustion duct 4 is an air passage for supplying the gas burner 6 with the outdoor air sucked from the outside and the fuel gas introduced from the fuel gas supply means 7.

The combustion blower 5 is rotationally driven by the electric motor 51 and its electric motor 51 whose rotational speed changes in accordance with the amount of energization, so that the combustion blower 5 is moved outdoors in the combustion duct 4 and the gas burner 6. It has a combustion fan 52 which generates a directed air flow.

The gas burner 6 is a burner of the present invention and has a combustion plate 61.

One end of the heat exchanger 61 is connected to the combustion case 62 to exchange heat between the air passing through the hot air duct 2 and the internal combustion heat. The other end of this heat exchanger 61 is connected to the exhaust duct 63. The combustion case 62 arrange | positions the derma coupler 12 and the spar electrode 13 downstream of the combustion plate 64. As shown in FIG. The exhaust duct 63 is an air passage for discharging the combustion exhaust of the mixer to the outside.

The fuel gas supply means 7 has a 1st kettle valve 71, a 2nd kettle valve 72, a flow control orifice 73, a proportional control valve 74, and the gas piping 75 which provided these.

As for the 1st main solenoid valve 71 and the 2nd kettle valve 72, a valve will open when electricity is supplied, and a valve will close when electricity supply is stopped. The orifice 73 is disposed in parallel with the proportional control valve 74 to steer the supply amount of fuel gas (hereinafter referred to as gas amount). The proportional control valve 74 is a valve which changes the supply pressure of the fuel gas by changing the opening ratio of the gas pipe 75 in accordance with the amount of energization, and adjusts the gas amount of the fuel gas.

The microcomputer 10, as the control means of the present invention, inputs signals from the dummyster 11, the decoupler 12, the spark electrode 13, the motion switch 14 and the temperature control button 15. To control the set temperature indicator 16. The temperature control button 15 is a setter for setting a set temperature. The set temperature indicator 16 displays the set temperature set by the temperature control button 15. The overheat safety device 17 is a temperature fuse or dummyster disposed in the cabin of the FF gas hot air heater 1, and the microcomputer 10 stops the heating operation when the temperature in the cabin rises above a predetermined value. Signal).

The microcomputer 10, according to the electrical signals sent from the dummyster 11, the thermocouple 12, the operation switch 14, the temperature button 15 and the overheat safety device 17, the spark electrode ( 13), the electric motors 31 and 51, the first kettle valve 71, the second kettle valve 72, the proportional control valve 74 and the set temperature indicator 16 is controlled.

In addition, the microcomputer 10 changes the combustion state of the gas burner 6 in eight steps gently from the low combustion control to the high combustion control in response to the room temperature and the set temperature during the normal combustion control. That is, the microcomputer 10 changes the energization amount of the electric motor 51 and the proportional control valve 74 in eight stages from the low burned state to the low burned state in response to the room temperature and the set temperature. Let's do it.

Then, when the microcomputer 10 switches the combustion state of the gas burner 6 to the increase side, the blowing amount of the convection fan 32 (electric power) is changed in accordance with the rate of change of the gas amount (the amount of electricity supplied to the proportional control valve 74). The amount of energization to the motor 31) is changed at the first change rate. In this case, the first holding time of each air flow rate step of the airflow amount of the convection fan 32 is set to be substantially the same as the holding time of each step of the gas amount.

In addition, when the microcomputer 10 switches the combustion state of the gas burner 6 to the reduction side, the blowing amount of the convection fan 32 is changed in accordance with the rate of change of the gas amount (current flow amount to the proportionality control valve 74). (The amount of energization to the electric motor 31) is changed at the 2nd change speed. In this case, the second holding time for each air flow stage of the airflow amount of the convection fan 32 is set longer than the first holding time for each stage of the gas volume by a predetermined time (see the graph of FIG. 2).

Here, in the graph of FIG. 2, the solid line shows the 1st rate of change of the amount of gas to the gas burner 6, and the broken line shows the 2nd rate of change of the blowing amount of the convection fan 32. As shown in FIG.

3 shows a pull chart indicating the main control of the microcomputer 10.

First, room temperature is detected (step S1), the set temperature is read (step S2), and a target range (for example, set temperature ± 2 ° C) is calculated from the set temperature (step S3), and the room temperature is higher than the target range. It is judged whether it is rising (step S4). When room temperature> target range (Yes), the weak combustion control subroutine shown in FIG. 4 is performed (step S5), and control of step S1 is performed.

In step S4, when it is not the room temperature target range (No), it is judged whether room temperature falls below the target range (step s6). When room temperature <target range (Yes), a strong combustion control routine is performed (step S7), and control of step S1 is performed.

When it is not room temperature <target range (No) in step S6, a normal combustion control subroutine is performed (step S3), and control of step S1 is performed.

In addition, the normal combustion is switched to six stages depending on the difference between the room temperature and the actual temperature between the strong combustion and the weak combustion.

4 shows a western routine showing weak combustion control of the microcomputer 10.

In step S4, it is determined whether the combustion state of the gas burner 6 is a weak combustion state when room temperature> target range Day (Yes). That is, it is determined whether the minimum amount of energization is supplied to the proportional control valve 74 (step S22). When the combustion state of the gas burner 6 is a weak combustion state Yes, control of the step S25 is performed.

In step S21, when the combustion state of the gas burner 6 is not a weak combustion state (NO), the amount of energization supplied to the electric motor 51 is reduced (-1) by only one step (step S22) and proportionally. The amount of energization supplied to the control valve 74 is reduced (-1) by only one step (step S23).

Next, it is determined whether the first holding time (for example, 2 seconds) has elapsed (step S24). When the first holding time has elapsed (Yes), the control in step S21 is performed.

In step S24, when the holding time has not elapsed (No), it is determined whether the airflow amount of the convection fan 32 is a weak air volume. That is, it is determined whether or not the minimum power supply amount is supplied to the electric motor 31 (step S25). When the minimum power supply amount is supplied to the electric motor 31 (Yes), the western routine is finished.

In step S25, when the minimum energization amount is not supplied to the electric motor 31 (No), it is determined whether the second holding time (for example, 5 seconds) has elapsed (step S26). When the second holding time has not elapsed (No), control of step S24 is performed.

In step S26, when the second holding time elapses (Yes), the amount of current supplied to the electric motor 31 is reduced by one step (-1) (step S27). Then, control of step S24 is performed.

The FF gas hot air heater 1 of this embodiment is demonstrated based on FIG. 1 and FIG.

When the operation switch 14 is set on the "on" side, the forced "strong" operation is performed until the FF gas hot air heater 1 passes for a predetermined time. After the forced "strong" operation, the gas burner 6 is burned in accordance with the temperature difference between the room temperature detected by the dummy computer 11 by the microcomputer 10 and the set temperature set by the temperature control button 15. The state is controlled.

For example, when switching the combustion state of the gas burner 6 from a strong combustion state to a weak combustion state, the electricity supply amount supplied to the electric motor 51 and the proportional control valve 74 of the combustion blower 5 is carried out. To decrease. The electric motor 51 and the proportional control valve 74 each time the holding time (for example, 2 seconds) elapses until the minimum amount of energization supplied to the electric motor 51 and the proportional control valve 74 is reached. Reduce the amount of electricity supplied to the unit by one step.

In other words, the amount of current supplied to the electric motor 51 and the proportional control valve 74 decreases at a predetermined change rate until the amount of current supplied from the maximum current amount is the minimum current value (see FIG. 2 graph).

Therefore, as the rotational speed of the combustion fan 52 decreases step by step, the blowing amount of the combustion fan 52 is changed from the strong wind amount to the weak air amount through six air volume steps. This reduces the amount of air supplied to the gas burner 6 by the outdoor air (combustion air).

In addition, the opening ratio of the gas piping 75 is reduced by the proportional control valve 74 corresponding to the increase in the amount of air, so that the gas amount of the fuel gas supplied to the gas burner 6 is also reduced. Therefore, even when the combustion state of the gas burner 6 is switched from the strong combustion state to the weak combustion state, the mixer having the optimum air-fuel ratio is supplied to the gas burner 6.

On the other hand, in the convection blower 3, the electric motor 31 is energized at the maximum energization amount until the second holding time (for example, 5 seconds) elapses. For this reason, the indoor air sucked into the hot air duct 2 from the suction port 21 by the rotation of the convection fan 32 is heated when passing around the heat exchanger 61, and becomes warm air of a predetermined temperature. In addition, when the indoor air passes through the hot air duct 2, the indoor temperature of the FF-type gas hot air heater 1 which is being operated by the steel combustion state is lowered. For this reason, since the cabin temperature does not become high temperature, the cabin temperature of the microgas hot air heater 1 is reduced. As a result, the cabin temperature does not become high temperature, thereby preventing malfunction of electrical equipment such as the microcomputer 10, the dummyster 11, and the overheat safety device 17.

Then, when the second holding time elapses, the amount of current supplied to the electric motor 31 of the convection blower 3 is reduced to the amount of current flowing in the seventh stage. Thereafter, the amount of current supplied to the electric motor 31 decreases step by step each time the second maintenance interval elapses until the amount of current supplied to the electric motor 31 reaches the minimum current amount. In other words, the amount of current supplied to the electric motor 31 decreases at the second conversion speed from the maximum amount of current supply to the minimum amount of current supply (see second diagram and graph).

Therefore, the blowing amount of the convection fan 32 is delayed from the combustion state of the gas burner 6, and is switched from the strong wind amount to the weak air amount through the six air volume steps. For this reason, since the airflow amount of the convection fan 32 is comparatively larger than the combustion state of the gas burner 6 until it switches from a strong wind volume to a weak air volume, the FF type hot air heater 1 by the convection fan 32 as mentioned above. ), The cabin is cooled. In addition, the blowing amount of the convection fan 32 is not maintained at the reduced wind amount for a long time (for example, 35 seconds) from the strong wind amount to the low wind amount. That is, since the operation time of the strong wind amount is reduced, and the air volume of the convection fan 32 does not suddenly switch from the strong wind amount to the weak wind amount, the cabin of the FF type gas warm air heater 1 is not cooled too much. Therefore, it is possible to prevent cold air from blowing from the hot air duct 2 toward the room interior.

Therefore, the heating peeling in the FF type gas hot air presenter 1 can be improved compared with the conventional apparatus.

In the present embodiment, a predetermined time is used when the air flow rate of the convection fan is changed from the strong wind volume to the weak air volume through a plurality of air volume stages, but the air volume of the convection fan is changed from the strong wind volume to the weak air volume through the plurality of air volume stages. At the time of conveyance, the predetermined time may be shortened as the amount of air flow approaches.

In the present embodiment, fuel gas is used as fuel, but liquid fuel may be used as fuel.

In the present embodiment, the hot air heater is used for the FF gas hot air heater, but the hot air heater may be used for another hot air heater such as a fan heater.

Claims (1)

A warm air duct for directing air to the interior, a convection blower for generating an air flow toward the interior in the warm air duct, a burner for burning fuel and heating air passing through the warm air duct, and the burner In a warm air conditioner having a control means for controlling the convection blower in accordance with the combustion state of the gas, the control means is a gas for weak to switch the combustion state of the burner from the low combustion state to the low combustion state through a plurality of combustion steps A switching means, a delay means for delaying switching of the air flow rate of the convection blower by a predetermined time corresponding to the gas weakening switching means, and a plurality of air volume steps while delaying each of the plurality of air flow steps by the delay means by the delay time. Blowing air volume conversion for converting the air volume of the convection blower from the strong wind volume to the weak air volume through Hot air heaters, comprising a.