JPH03167025A - Controller for combustion type heater - Google Patents

Abstract

PURPOSE:To provide always a proper combustion state by storing a missed combustion start condition in a memory when the combustion start condition is not detected even after a predetermined time in spite of the start of a combustion type heater, and increasing an air fuel ratio by a predetermined amount when the recombustion is carried out thereafter. CONSTITUTION:A manual switch 24 for outputting a starting signal to start a combustion type heater and a flame sensor 21 for detecting a combustion start condition are provided where engine cooling water flowing into a heater core of an air conditioner is heated by combustion gas generated by the combustion type heater to aid a heating capacity. The output signals of these switch and sensor are inputted in a control section 30. When the combustion start condition is not detected even after a predetermined time in spite of the output of the starting signal, the combustion start is judged to be missed so that such a condition is stored in a memory 31. Also, when the combustion start condition is detected thereafter, a fuel pump 2 constituting part of an air fuel ration controlling means is controlled to reduce fuel supplied to the combustion type heater by a predetermined amount.

Description

[Detailed Description of the Invention] [Purpose of Invention] (Industrial Applications) The present invention relates to a control device for a combustion type heater that assists the heating capacity of an air conditioner for an automobile, and is directed to a control device for a combustion type heater that assists the heating capacity of an air conditioner for an automobile. The present invention relates to a control device for a combustion type heater, which can increase the combustion ratio by a predetermined amount to perform proper combustion when re-igniting after the occurrence of the combustion.

(Prior art) Vehicles are generally equipped with an air conditioner that heats the interior of the vehicle, but for example, in vehicles with relatively large interior volumes such as microbuses and one-box cars, when the outside air is cold, the room temperature is Problems such as the lack of heating capacity of the air conditioner, such as the time it takes to raise the temperature, may occur.

Therefore, in the past, vehicles were equipped with a heating auxiliary system K called a combustion heater, which forcibly boosts the engine cooling water by burning fuel such as light oil and assists the heating capacity of the air conditioner. be.

Such a combustion type heater is disclosed in Utility Model Application No. 57-128506.
It is disclosed in the publication number etc. In addition, conventionally, for example, the fourth
There is something like the one shown in the figure.

The combustion type heater 1 shown in FIG. 161 is located in the engine cooling system and is connected in series to the heater core of the air conditioner.
It heats the cooling water that flows into the heater core. It looks like this.

The combustion heater 1 mixes fuel, which is supplied from a fuel tank (not shown) to a vaporization mat 3 by a fuel pump 2 and vaporized thereby, with combustion air supplied by a blower 4 in a combustion chamber 5. The air-fuel mixture formed by this is ignited by the globe lug 6 and is continuously combusted within the combustion chamber 5.

The combustion gas thus formed is turned around at the tip of the combustion tube 7, passes between the outer wall of the combustion tube 7 and the heat transfer tube 8, and is discharged to the outside from the exhaust port 9. .

On the other hand, the engine cooling water heated by the combustion heater 1 is guided by the water pump 10 to the passage 12 between the inner wall of the outer cylinder 11 and the outer wall of the heat transfer tube 8, and is heated by the heat transfer tube 8. It is led into the heater core from the discharge port 13. Thereby, the heater core into which the heated cooling water flows can perform heat exchange between the air supplied into the vehicle interior and the cooling water, and can sufficiently heat the vehicle interior.

Each part of this combustion type heater 1 is provided with each scale sensor for controlling combustion, and these are as follows.
They are each connected to a control device 20 that controls this combustion type heater 1 .

As shown in the figure, the combustion type heater 1 includes a flame sensor 21 that detects the temperature inside the combustion chamber 5, a water temperature sensor 22 that detects the temperature of cooling water, and an overheat sensor 1 that detects the surface temperature of the heat transfer tube 8. 23 are arranged respectively, and each insertion temperature information detected by these sensors is sent to the control device 20.
It is becoming more and more human-powered.

The control device 20 then turns on a manual switch 24 that is turned on by the passenger when operating this combustion type heater.
, The OFF state is manually controlled, and this is the ON state.
Then, based on the temperature information from those sensors,
For example, as shown in FIG. 5, a fuel pump 2, a blower 4,
The globe lug 6 and water pump 10 are controlled to control combustion so that the temperature of the cooling water heated by this combustion type heater falls within a predetermined temperature range.

Furthermore, since such a combustion type heater is used when the outside air is relatively low temperature, it is started when the temperature inside the combustion chamber 5 and the combustion tube 7 is low. Sometimes ignition is not always achieved reliably. Therefore, in the conventional control device 20, if a so-called ignition error occurs in which the ignition is not ignited even after a predetermined period of time has elapsed during startup, as shown in FIG. Some devices are designed to control pump 2.

5. As shown in the figure, when the manual switch 24 is turned on, the control unit 20 first applies a predetermined amount of electricity to the glove lug 6 to preheat it. After the time has elapsed for the globe lugs 6 to be heated to a temperature necessary for ignition, the fuel pump 2 is operated to supply fuel vaporized by the vaporization mat 3 into the combustion chamber 5. At this time, the control device 20 also operates the blower 4 to supply air into the combustion chamber 5 as well as vaporized fuel.

Then, as shown in the figure, the control device 20 determines whether the temperature inside the combustion chamber 5 did not rise above a predetermined mixture level by the flame sensor 21 during a predetermined period of time (90 seconds in the figure) in this state. In other words, if ignition does not occur and combustion does not start, the power supply to the globe lug 6 and the fuel pump 2 is temporarily stopped to stop their operation. After that, only the blower 4 is operated for a predetermined period of time (approximately 80 seconds) to scavenge the inside of the combustion chamber 5, and then the fuel pump 2,
The blower 4 and the globe lag 6 are operated to re-ignite the fire.

6 (Problems to be Solved by the Invention) However, in such conventional combustion heaters, once combustion is started by automatically re-igniting, there is no problem for a while after ignition. Complete combustion may occur. This is because fuel that has landed on the low-temperature inner wall of the combustion cylinder due to an initial ignition error may not be removed even by scavenging, so when it is re-ignited, this fuel will be burned at the same time. This is because the amount of fuel to be combusted increases and the air-fuel ratio within the combustion chamber 5 temporarily decreases. This has caused problems such as proper combustion not being carried out until such excess fuel has finished burning after the fire.

The present invention was made in order to solve these conventional problems, and it is possible to reduce the air-fuel ratio between the air and fuel supplied into the combustion chamber when re-igniting the moss after an ignition error has occurred. The purpose of the present invention is to provide a control system for a combustion type heater that can be increased by a predetermined amount to perform proper combustion.

[Structure of the Invention] (Means for Solving the Problem) In order to achieve the above-mentioned object, the present invention includes a combustion chamber for burning fuel, and uses the heat generated from the combustion chamber to generate an air conditioner for an automobile. In a control device for a combustion type heater that heats engine cooling water flowing into a heater core of a vehicle before it flows in and assists the heating capacity of an air conditioner for an automobile, a starting signal output means outputs a starting signal to start the combustion type heater. a combustion start detection means for detecting a combustion start state in which combustion starts in the combustion chamber; and a combustion start detection means for detecting a combustion start state where combustion starts in the combustion chamber; storage means for storing that the combustion start detection stage is in a combustion start miss state in which the combustion start state is not detected; The present invention is characterized by comprising an air-fuel ratio control stage for increasing the air-fuel ratio of air and fuel supplied to the combustion chamber by a predetermined amount when the detection means detects the combustion start state.

(Function) The present invention configured as described in Section 12 functions as follows.

Even though the starting signal is output from the starting signal output means and the combustion type heater is started, if the combustion start detection stage or combustion start state is not detected even after a predetermined period of time has elapsed, in other words, ignition occurs at the time of starting. If not, it is stored in the storage means that there is a combustion start error state, that is, an ignition error has occurred. After this, when the combustion start detection means detects a combustion start state, that is, when re-ignition occurs, the air-fuel ratio control means reduces the fuel by a predetermined amount or increases the air by a predetermined amount. The air-fuel ratio between air and fuel supplied into the combustion chamber is increased by a predetermined amount. This causes ignition errors during startup,
In the case of re-ignition, air is supplied into the combustion chamber that can completely burn the fuel remaining in the combustion chamber due to ignition error and the newly supplied fuel, allowing proper combustion to occur. ) will be able to do things.

(Example) 9 Below, a +U control device for a combustion type heater according to the present invention will be explained in detail based on the drawings.

FIG. 1 is a schematic configuration diagram of a control device for a combustion type heater according to the present invention, and FIG. 2 is an operational flowchart of this control device. Further, FIG. 3 shows an operation flowchart of the control device as another embodiment.

Incidentally, in these figures, the same parts as those described in the prior art are marked with the same reference numerals -3 and f.1. Furthermore, since the structure of the combustion type heater is the same as that of the conventional one, a detailed explanation thereof will be omitted here.

As shown in FIG. 1, a flame sensor 21 serving as a combustion start detection means for detecting the temperature in the combustion chamber 5 of the combustion heater 1 (hereinafter referred to as combustion chamber temperature) controls the detected combustion chamber temperature. The information is output to the section 30.

Further, the manual switch 24 as a starting signal output means that is turned on by the occupant when starting the combustion type heater 1 sends a starting signal to the control unit 30 to start the combustion type heater 1 as shown in 161 by being turned on. The output is 10.

The control unit 30 operates the fuel pump 2, blower 4, and globe lug 6 based on these starting signals and the combustion chamber temperature. This control unit 30 is provided in the control device 20 described in the conventional technology, and the control device 20 is operated in the same manner as in the conventional technology except for the control to ignite and reignite, which will be explained below. The combustion type heater 1 is controlled.

Furthermore, the blower 4 can increase or decrease the amount of air supplied into the combustion chamber 5 according to the 7h pressure output by the control section 30, and when the control section 30 increases the voltage. is designed to increase its air volume by the increased amount.

Further, the control unit 30 includes a memory 31 for storing the occurrence of an ignition error, and a control unit 3 for determining the occurrence of an ignition error and controlling the time for increasing the fuel narrowing ratio.
A timer 32 for measuring the time required by L, which is controlled by 0, is connected to each of the timers 32.

1.1 The control unit 30 operates the fuel pump 2, blower 4, and globe lug 6 to automatically re-ignite the ignition if an ignition error occurs during startup, as in the conventional case 161. If the ignition does not occur even after this, it is determined that there is an abnormality, and the power supply to the fuel pump 2, blower 4, and globe lug 6 is stopped, their operation is stopped, and the combustion type The heater 1 is not activated.

Furthermore, the control unit 30 controls the blower 4 when the ignition occurs again.
The voltage supplied to the combustion chamber 5 is increased by a predetermined amount, and the amount of air supplied into the combustion chamber 5 by the blower 4 is increased by a predetermined amount. In other words, the control unit 30 increases the amount of combustion air by a predetermined amount in the case of re-ignition.
The air-fuel ratio between the fuel and air supplied into the combustion chamber 5 is increased by a predetermined amount, and the fuel remaining in the combustion chamber 5 due to ignition error and the newly supplied fuel are completely combusted.

With such a configuration, the control system for the main strike operates based on the operation flowchart 1 shown in FIG.

First, the control unit 30 sends the start signal 5 from the operation switch 24.
When 3 is input, 1 is assigned to the flag n in the memory 31 to remember that this is the first ignition operation (step 1), and a predetermined voltage is applied to the globe lag 6 to compensate for this. to preheat the glove lugs 6 (step 2).

Then, the control unit 30 waits until the time period pQ (r set in the timer 32) has elapsed during which the globe lug 6 is disturbed to a temperature necessary for a stone fire (step 3),
When the heating time has elapsed, the fuel bomb 2 and the blower 4
is operated to supply fuel and air into the combustion chamber 5 and start combustion (step 4).

Then, the control unit 30 manually inputs the temperature in the combustion chamber output by the flame sensor 21, and determines whether or not this temperature reaches a predetermined temperature corresponding to the combustion start state in which combustion has started within a predetermined time (90 seconds after starting the fuel pump). It is determined whether ignition has occurred by determining whether ignition has occurred (step 5).
, 6).

13 Then, if the control unit 30 determines that the combustion chamber temperature manually measured from the flame sensor 21 did not rise above the predetermined temperature within the predetermined period of time and ignition did not occur in steps 5 and 6, in preparation for the next ignition operation, The operation of the fuel pump 2 is stopped (step 7), and only the blower 4 is operated for the scavenging time required for scavenging (preset in the timer 32) to scavenge the inside of the combustion chamber 5, and then the blower 4 is activated. (steps 8 and 9).

Furthermore, the control unit 30 adds 1 to the flag n in the memory 31 to store that an ignition error has occurred (step 1
0), until the flag n becomes 3, the process returns to step 1 and the re-ignition operation is performed (step 11). When this flag n becomes 3, that is, when the ignition does not occur despite the re-ignition operation, the process ends.

Then, the control unit 30 controls the flame sensor 2 in steps 5 and 6 by the initial ignition operation or re-ignition operation.
If the temperature in the combustion chamber manually controlled from 1 becomes higher than the predetermined temperature within the predetermined time and ignition occurs, it is determined whether the flag n is 2 or not, and if the flag n is not 2, that is. If the flag n is 1 and the water is lit by the first stone fire operation, the flag n is reset and the process proceeds to step 16, where the normal heating control mode shown in Fig. 5 is entered and the water temperature reaches a predetermined mixture level. Combustion is controlled so that the area is covered with notes (step 12).

-h, when the flag n is 2 and the ignition is caused by the re-ignition operation, the control unit 30 sets a predetermined value from the re-ignition in order to completely burn the surplus fuel remaining in the combustion chamber 5 due to the ignition error. until the time (approximately 30 seconds) has elapsed.
One loaf to be supplied at a predetermined time t1. (step 13.14). At this time, the fuel pump 2 is supplied with air that is increased by a predetermined amount more than the amount required for combustion (step 13.14). At this time, the fuel pump 2 is A voltage is applied to supply the necessary fuel, and as a result, the air-fuel ratio between the air and fuel supplied into the combustion chamber 5 increases by a predetermined amount. The surplus fuel is properly combusted by the increased air, and complete combustion is achieved within the combustion chamber 515.

When the control unit 30 determines that a predetermined period of time has elapsed since the ignition, and that the remaining fuel due to the ignition error has been completely combusted by the increased air, the control unit 30 changes the voltage applied to the blower 4 to the normal combustion voltage. The amount of constricted air supplied into the combustion chamber 5 is set to the amount of air necessary for normal combustion, the flag n is reset, the mode shifts to normal heating control mode, and combustion is controlled so that the water temperature falls within a predetermined temperature range ( Step 15.16).

Therefore, if the control unit 30 manually inputs the starting signal and performs the ignition operation, but the ignition does not occur, the control unit 30 performs the ignition operation again, and if the ignition is thereby ignited,
In other words, in order to completely burn the fuel remaining in the combustion chamber 5 due to the initial ignition error when igniting again, the combustion chamber 5
Since the amount of air supplied into the combustion chamber 5 is increased by a predetermined amount, the combustion state within the combustion chamber 5 becomes favorable after re-ignition until the remaining fuel is completely combusted. This prevents incomplete combustion after re-ignition.

In addition to the embodiment described in L, as shown in FIG.
The air-fuel ratio after re-ignition may be increased by a predetermined amount. In this case, the control unit 30 reduces ah supplied to the fuel pump 2 by a predetermined amount, so that the amount of fuel discharged from the fuel pump 2 is reduced by a predetermined amount. still,
Steps 20 to 30 shown in the ICiJ diagram are the same as the initial ignition and re-ignition operations of steps 1 to 11 shown in FIG. 2, so explanation ① will be omitted here.

As shown in FIG. 161, the control unit 30 causes the temperature in the combustion chamber manually measured from the flame sensor 21 to rise to a predetermined temperature or higher within a predetermined time due to the initial ignition operation or re-ignition operation in steps 24 and 25, and the ignition is started. When it is determined that
It is determined whether the flag n is 2 or not, and if the flag n is not 2, that is, if the flag n is 1 and there is a spark in the first ignition operation, the flag n is reset to 1 and the process proceeds to step 3.
Step 5 proceeds to the normal heating control mode shown in FIG. 5 in the same way as in the previous embodiment and 161, and combustion is controlled so that the water temperature falls within a predetermined temperature range 1 (step 31).

17 On the other hand, when the flag n is 2 and ignition is caused by the re-ignition operation described in 1;, the control unit 30 completely removes the residual fuel remaining due to the ignition error in the combustion chamber 5 with the air necessary for normal combustion. In order to cause combustion, the voltage supplied to the fuel pump 2 is reduced by a predetermined amount until a predetermined time (approximately 30 seconds) has elapsed since re-ignition, and the fuel is burned by a predetermined amount less than that required for normal combustion. It is supplied into the chamber 5 (steps 32, 33). At this time, a voltage is applied to the blower 4 to supply air necessary for normal combustion, and as a result, the air-fuel ratio between the air and fuel supplied into the combustion chamber 5 increases by a predetermined amount. In other words, by reducing the amount of fuel supplied into the combustion chamber 5 by the amount of residual fuel, the fuel in the combustion chamber 5 including the residual fuel is properly combusted by the air necessary for normal combustion, and the fuel in the combustion chamber 5 is completely burned. Combustion takes place.

When the control unit 30 determines that a predetermined period of time has elapsed since the ignition and that the remaining fuel due to the ignition error has been completely burned, the control unit 30 changes the electric power applied to the fuel pump 2 to the electric sweat during normal combustion. The amount of fuel supplied into the combustion chamber 5 is set to the amount necessary for normal combustion, and the flag n is set.
Reset 1 to switch to normal heating control mode, and control combustion so that the water temperature falls within the predetermined temperature range (step 3).
4.35).

Therefore, even in this case, the combustion state in the combustion chamber 5 after re-ignition can be maintained in good condition, as in the above embodiment and 161.

In each of the above embodiments, in step 14 and step 33, the amount of air increased by a predetermined amount and the amount of fuel decreased by a predetermined amount are determined based on the elapsed time after re-ignition necessary for normal combustion. The amount of air and fuel has been returned to the normal amount, and the elapsed time is used to determine that the remaining fuel due to ignition error has finished burning. When the combustion becomes stable based on the temperature inside the combustion chamber 5, or when the light of the flame inside the combustion chamber 5 is detected by a light receiving element such as a photodiode, and the amount of this light exceeds a predetermined amount. Then,
Of course, the air amount and fuel amount may be returned to the normal state based on when the combustion state becomes stable.

Similarly, a flame sensor 2 is used as a stage for detecting the start of combustion.
Of course, 1 may be a light receiving element such as the photodiode described above.

Furthermore, although the manual switch 24 is illustrated as an example of a device that outputs an activation signal for activating the combustion type heater 1, it is not limited to this. For example, a timer or the like that activates the combustion type heater at a set time may also be used. Of course.

(Effects of the Invention) As is clear from the above description, the present invention has the following effects.

Even though the starting signal is output from the starting signal output means and the combustion type heater is started, if the combustion start detection stage does not detect the combustion start state even after a predetermined period of time has elapsed, in other words, ignition occurs at the time of starting. If not, the storage means stores that there is a combustion start error state, that is, an ignition mistake has occurred, and if the combustion start detection means detects a combustion start state after this, that is, re-ignition has occurred. 20, the air-fuel ratio control stage increases the air-fuel ratio of the air and fuel supplied into the combustion chamber by a predetermined amount by reducing the fuel by a predetermined amount or increasing the air by a predetermined amount, so that the starting Occasionally, an ignition error occurs, and if ignition occurs again, air will be supplied into the combustion chamber that can completely burn the fuel remaining in the combustion chamber due to the ignition error and the newly supplied fuel. This allows for proper combustion.

Therefore, when the fuel is re-ignited after an ignition error, the air-fuel ratio can be increased by a predetermined amount to achieve complete combustion.

Also, among the above, if the air-fuel ratio is increased by increasing the air supplied into the combustion chamber by a predetermined amount, more fuel will be generated in the combustion chamber due to the remaining fuel due to ignition error and the newly supplied fuel. The fuel will burn, and the calorific value after re-ignition will be greater than the calorific value after normal ignition.
Since the engine cooling water flowing into the heater core can be heated more quickly, there is also the effect that the interior of the vehicle can be heated more quickly.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a control device for a combustion type heater according to the present invention, FIG. 2 is an operation flowchart of this control device, and FIG. 3 is a control device for a combustion type heater according to another embodiment of the present invention. The operation flowchart of the device, FIGS. 4 to 6, are explanatory diagrams of a conventional combustion type heater control device. DESCRIPTION OF SYMBOLS 1... Combustion type heater, 2... Fuel pump (air-fuel ratio control means), 4... Blower (air-fuel ratio control means), 6...
- Globe lug, 21... Flame sensor (combustion start detection means), 24... Manual switch (starting signal output means), 30... Control section (air-fuel ratio control means), 31...
-Memory (storage means), 32... timer (air-fuel ratio control means).

Claims (1)

[Claims] A combustion chamber (5) for burning fuel, the combustion chamber (5)
A combustion type heater (1) that heats the engine cooling water that flows into the heater core of an automotive air conditioner using the heat generated from
), the control device includes a start signal output means (24) that outputs a start signal to start the combustion heater (1), and a combustion start unit that detects a combustion start state in which combustion starts in the combustion chamber (5). The combustion start detection means (21) does not detect the combustion start state even after a predetermined period of time has elapsed even though the start signal has been output from the detection means (21) and the start signal output means (24). a storage means (31) for storing that the combustion start error state is present; and a storage means (31) for storing the combustion start error state in the storage means (31), and the combustion start detection means (21) detecting the combustion start state A combustion type characterized by having an air-fuel ratio control means (2, 4, 30, 32) that increases the air-fuel ratio of air and fuel supplied to the combustion chamber (5) by a predetermined amount when detecting Heater control device.