JPS63169426A - Controller for combustion device - Google Patents

Abstract

PURPOSE:To control the temp. of a vaporization glow plug at the vaporization temp. of fuel by installing a timer control means controlling current-conduction to an ignition plug and also a means controlling current-conduction on the basis of the signal from a temp. measuring means for a vaporization glow plug. CONSTITUTION:Current to an ignition glow plug 6 is supplied by timer control commanded by a controller 8 and when current-conduction time has exceeded a specified set time, current to a vaporization plug 5 is supplied. The resistor 5a of a current-carrying circuit is connected in series to the heating heater of the plug 5 and by the measurement of both end voltages of the resistor 5a the resistance value of the heater is detected and since the heater has a positive temp. resistance coefficient, the temp. of the plug 5 is detected by discovering the resistance value of the heater. Consequently, since the temp. of the vaporization glow plug can be controlled at a suitable value by controlling the current to the heater with a limiting resistor 5b, the vaporization of supplied fuel is completely carried out and poor combustion caused by poor vaporization and the carbonization of fuel due to overheat can be avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a control device for a combustor used in a heating device that rapidly heats the interior of a vehicle driven by an internal combustion engine.

A combustion chamber with a vaporizing glow plug that vaporizes fuel and an ignition glow plug that ignites the vaporized fuel is installed in the middle of the engine's air duct, and a part of the air that reaches the engine is used to burn the fuel as a heat source for heating. Japanese Patent Application No. 59-281155 proposes controlling the heating of an ignition glow plug for a heating system using a temperature signal from its heating resistance wire and a signal from a timer device. Shown as a control device.

(Problems to be Solved by the Invention) In the proposal shown in the above-mentioned Japanese Patent Application No. 59-281155, the temperature of the ignition glow plug is controlled, but the temperature of the vaporizing glow plug that vaporizes the fuel is not controlled. There are no drawbacks.

In other words, the appropriate vaporization temperature for fuel is, for example, 500°C.
If the vaporizing glow plugs do not reach the front and rear, sufficient fuel will not be vaporized, resulting in poor combustion, and if the temperature of the vaporizing glow plugs is too high, there is a real risk that the fuel will carbonize and clog the fuel flow path. The invention was made in view of these problems, and its purpose is to provide a resistor connected in series to a vaporizing glow plug, measure the voltage between both terminals of the resistor, and determine the temperature resistance coefficient of the heater. It detects the temperature and uses this to control the energization to the vaporizing glow plug to control the temperature of the vaporizing glow plug to an appropriate vaporizing temperature, while the energization to the 1-ignition glow plug is controlled by a timer to control the temperature. To provide a control device for a combustor.

(Means for Solving the Problems) According to the present invention, in a control device for a combustor having a vaporizing glow plug and an ignition glow plug, each of which is provided with a heater having a temperature resistance coefficient, the vaporizing glow plug is connected in series to the vaporizing glow plug. temperature measuring means that measures the temperature of the vaporizing glove and lug by measuring the terminal voltage of the resistor, and control that controls the energization to the vaporizing glow plug based on the signal from the temperature measuring means to control its temperature to an appropriate value. There is provided a control device for a combustor, which is provided with an energizing means for timer-controlling energization of the ignition glow plug.

(Function) In the present invention, a resistor having a minute resistance value is connected in series to the supply line to the vaporizing glow plug, and the terminal voltage is measured when the vaporizing glow plug is energized. It has the function of detecting the value and detecting the temperature, and also controls the supply current limiting resistor based on the detected temperature to control the current of the heater, so the temperature of the vaporizing glow plug can be adjusted to the temperature of the vaporizing fuel. It has a controllable effect on temperature.

Furthermore, the temperature of the single ignition glow plug can be controlled to the ignition temperature by controlling the power supply to the heater with a timer.

(Example) Next, an example of the present invention will be described in detail using the drawings.

FIG. 1 is a block diagram of the main parts of an embodiment of the present invention, and FIG. 2 is a processing flow diagram showing control of the present invention.

In FIG. 1, 1 is an intake pipe, a bypass flow path 1a leading to an engine (not shown) is provided with a bypass valve 2 for controlling the flow path, and a bypass valve actuator 2 is provided.
Its opening and closing is controlled by a. lb is an introduction pipe, which introduces atmospheric air into the combustor from the intake pipe 1.The introduced air is sent to the combustor 3 for fuel combustion, and the combustion gas is sent to the heat exchanger 4 for heating. After the heat is recovered, the air is sent to the engine via the return pipe 1c.

The combustion chamber 3a provided in the combustor 3 is equipped with a vaporizing glow plug 5 for vaporizing fuel and an ignition glow plug 6 for igniting the vaporized fuel. It is mixed with air and combusted.

The vaporizing glow plug 5 is composed of a cylindrical ceramic pipe having a heater whose resistance value changes in response to temperature changes.
d, and is vaporized and ejected from the tip into the combustion chamber 3a. A resistor 5a having a value of q9, 11, and a limiting resistor 5b for limiting the supply current are connected in series to the input terminal. 5b is connected in parallel with a short-circuit changeover switch 5C, which releases the current restriction in the event of a short-circuit. In addition,
When the heater of the vaporizing glow plug 5 is energized, by measuring the terminal voltage of the resistor 5a, that is, the voltage drop value, a change in the resistance value of the heater due to temperature can be detected, and therefore the temperature of the heater can be detected. ing. Although the vaporization temperature varies depending on the nature of the fuel, for example, the temperature of a vaporization glow plug is set at around 500°C.

The ignition glow plug 6 is equipped with a heater whose resistance value changes in response to temperature changes similar to the vaporization glow plug 5, and a limiting resistor 6a is connected in series to its supply line, and the limiting resistor 6 & is further short-circuited. A changeover switch 6b is connected in parallel with the limiting resistor 6a. Therefore, in order to rapidly increase the temperature of the ignition glow plug 6, it is sufficient to turn on the selector switch 6b and short-circuit the limiting resistor 6a. It is configured such that the temperature of the ignition glow plug 6 can be detected by passing a minute current through it. The power supply to the ignition glow plug 6 is time-controlled by a timer included in the controller, which will be described later.

3b is a flame sensor that detects the combustion state inside the combustion chamber 3a, and sends a detection signal to the controller 8.

Reference numeral 4a denotes a blower, which takes in new air, sends it to the heat exchanger 4, and blows warm air that has exchanged heat with combustion gas from the combustor 3 into the vehicle interior.The blower 4a is controlled by a controller. This is done by commands from 8. Note that 4b is a heat exchanger sensor that detects the temperature of the heat exchanger 4;
4c is a hot air sensor that detects the temperature of the hot air being blown, and 4d is a Co sensor that detects the content of carbon monoxide in the blown hot air. Signals from these sensors are sent to the controller 8.

The controller 8 is composed of a microcomputer,
Central American processing equipment that performs calculation processing and various timer processing, various memories that store calculation results and control programs, etc., and input/output
It has an output device, etc., and has the above-mentioned vaporizing glow plug 5.
The signal from the micro resistor 5a, the flame sensor 3b,
It inputs signals from various sensors in addition to signals from the heat exchanger sensor 4b, hot air sensor 4c, etc., and also issues control signals to various operating parts such as the changeover switches 5c and 6b and the bypass valve actuator 2a. It is configured like this.

In addition, ld is an air temperature sensor provided in the introduction pipe 1b, 9a is a water temperature sensor that detects the cooling water temperature, 9b is an engine load sensor that detects the engine load state, and 9c is a heating body weight that sets the heating temperature in the passenger compartment. The switches are connected to the controller 8, respectively.

Reference numeral 10 denotes a battery, which serves as a power source for related parts of the heater, and the control operation of the controller 8 is started by turning on the start switch 10a.

Next, the control of this embodiment will be explained with reference to FIG.

In step 1, the start switch 10a is turned on, power is supplied from the battery 10 to the controller 8, and other related components are ready for operation. In step 2, the water temperature signal Tw from the water temperature sensor 9a is read. Water temperature signal Tw
If the water temperature signal Tw is lower than the predetermined cooling water temperature T1, the process proceeds to step 3 to activate the heater, and if the water temperature signal Tw is high, the heater is not needed and the process proceeds to the flow of not activating the heater, which will be described later.

In step 3, in order to know the temperature of the ignition glow plug 6,
The changeover switch 6b is closed, a measuring current is passed through the heater of the ignition glow plug 6, and the resistance value R of the heater is measured. This is because the heater uses a resistor with a positive temperature resistance coefficient, so if the resistance value is large, it can be detected that the temperature is high. If the resistance value of the heater measured in step 4 is greater than the predetermined value R, then in step 5 energization is performed under timer control according to a command from the controller 8, and in step 6 the energization time is 1. When the predetermined set time t has elapsed, the process proceeds to step 7 in which the vaporizing glow plug 5 is energized.If the energization time does not reach the set time t in step 6, the ignition glow plug is turned off in steps 8 and 9. The changeover switch 6C that short-circuits the limiting resistor 6b to the ignition glow plug 6 is turned on for a predetermined time period controlled by the timer of the controller 8 to increase the current.
control to speed up the temperature rise.

Further, if the resistance value R of the ignition glow plug 6 does not reach the predetermined resistance value R in step 4, in step 10, the temperature signal T from the temperature sensor ld provided in the introduction pipe 1a is
Check An. Then, when the predetermined temperature T2 is reached, the ignition glow plug 6 is energized, and step 12
The energization time tz is a predetermined set time t under timer control.
If the set time t has elapsed, the process proceeds to step 7, but if the set time t has not been reached, the process proceeds to step 7 after performing the same processes as steps 8 to 9 above in steps 13 to 14.

Furthermore, if the temperature signal TA- from the air temperature sensor 1d has not reached the predetermined temperature in step 10, step 1
In Step 5, the timer of the ignition glow plug 6 is turned on, and in Step 16, the energization time is checked. After processing the energization time and the operation of the changeover switch 6c in the same manner as in Step 12, the process goes to Step 7. move on.

After the vaporizing glow plug 5 is energized, the temperature of the vaporizing glow plug 5 is detected in step 19 by checking the voltage drop across the resistor 5a having a minute resistance value in the energizing circuit. this is,
The resistor 5a is connected in series with the heater of the vaporizing glow plug 5, and the resistance value of the heater can be detected by measuring the voltage across the resistor 5a.Furthermore, this heater has a positive temperature resistance. Since it has a coefficient, the temperature of the vaporizing glow plug 5 can be detected by knowing its resistance value. For example, the vaporizing glow plug 5 is 50
If the resistance value of the heater at 0°C is R500,
The resistance value RE of the vaporizing glow plug 5 is compared with R500, and if RE is larger than RlIOO, the supplied fuel can be vaporized, so the process proceeds to step 20, where the fuel switch 7 is turned on to supply fuel. In addition, the resistance value RE is R50
If it is smaller than 0, in step 21 selector switch 5 is
C is closed and the limiting resistor 5b is short-circuited to increase the current,
After controlling this energization time with a timer, the energization is turned off in step 22.

In step 23, the blower 4a is turned off and the air blowing to the heat exchanger 4 is stopped, and after checking whether the start position is on, the bypass valve 2 is actuated by the bypass valve actuator 2a to send combustion air (step 24 to 26), and in step 27, it is checked whether or not the engine is capable of self-operation. If the engine is capable of self-operation, the snap 28 is used to adjust the load state of the engine to a predetermined level based on the signal from the engine load sensor 9b. If the signal is lighter than the predetermined load L1 compared to the engine load L1, the process proceeds to step 29 and the signal of the heating position switch 9b is checked.

Note that if the engine is self-slashing and cannot rotate in step 27, then in step 30, after counting a predetermined time, a temperature signal TF5 based on the combustion state from the flame sensor 3b is sent.
is checked in step 31, and if the temperature is higher than the predetermined temperature T3, the process proceeds to the combustion stop flow, and if the temperature is lower than the predetermined temperature T3, the process returns to step 3 and the above flow is repeated.

If the signal from the heating position switch 9b is on in step 29, the bypass valve 2 is opened in step 32 to blow air to the combustor 3, and in step 33 the heat exchanger sensor 4b detects the heat exchanger 4. Check the temperature signal THE. Here, the temperature signal 7Hs is compared with a predetermined set temperature T5, and if the temperature signal THE is lower than T5, there is no abnormality, so the process proceeds to step 34 to blow air for heating, and the blower 4a is energized to perform heating. Start. If the temperature signal THE is higher than T5 in step 33, the temperature signal T F5 from the flame sensor 3b is checked in step 35 to check the combustion state, and if the temperature signal TFS is higher than the predetermined temperature T3, To stop combustion, if the temperature is low, return to step 3 and repeat the process.

After the air blower 4a is operated to start heating in step 34, the heating position from the heating position switch 9C is checked in step 36, and if the selected position is 1st, in step 37 the fuel switch 7C is checked.
is controlled to 1st and oil is sent to the combustor 3. Then, in step 38, the temperature of the hot air from the heat exchanger 4 is checked using the signal TA from the hot air temperature sensor 4C, and if it does not exceed the set temperature T4, a step is taken to check the amount of carbon monoxide in the hot air. If carbon monoxide is not detected by the signal from the CO sensor 4d, the process returns to step 3 from step 39 and the above process is repeated, but if the hot air temperature is too high in step 38, , step 39
If a predetermined amount of carbon monoxide is detected, proceed to the combustion stop flow.

In step 36, if the heating position is other than 1st, the process goes to step 40, and if the heating position is 2nd, the process goes to steps 41-42, and if the heating position is 3rd.
In this case, the process proceeds to steps 43 to 44, in which the openings of the blower 4a and the bypass valve 2 and the fuel flow rate of the fuel switch 7 are controlled to the operation and opening corresponding to the 2nd or 3rd, respectively. Controls the operation of the heater.

Steps 45, 46, and 47 are the flow for stopping the combustion of the heater, and if the temperature signal from the flame sensor is abnormally high in step 31 or the temperature of the hot air blowing out is too high in step 38, step 39 is executed. If carbon monoxide is detected in the hot air blown out, the blower 4a is stopped, the fuel switch 7 is closed, and the bypass valve 2 is fully opened to stop air flowing into the inlet pipe lb. After stopping the heating operation in step 3, the process proceeds to step 48 to set initial values for various timers, and returns to step 1 to repeat the flow.

Although the present invention has been described above using one embodiment, various modifications can be made within the scope of the gist of the present invention, and these are not excluded from the scope of the present invention.

(Effects of the Invention) In the present invention, a resistor having a small resistance value is connected in series to the supply line to the vaporizing glow plug provided in the combustion chamber, and the terminal voltage is measured when the vaporizing glow plug is energized. The temperature of the vaporizing glow plug can be detected by detecting the resistance value of the heater, which has a resistance coefficient, and by controlling the supply current limiting resistor, the current to the heating heater can be controlled to adjust the temperature of the vaporizing glow plug. Since the fuel is controlled to an appropriate value, the fuel being sent is sufficiently vaporized, which has the effect of solving problems such as poor combustion due to poor vaporization and carbonization of the fuel due to overheating.

Further, since the energization of the ignition glow plug is performed by timer control, there are fewer control members, which has the effect of reducing costs.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the main components of an embodiment of the present invention, and FIG. 2 is a processing flow diagram illustrating an example of its control. 3... Combustor, 4... Heat exchanger, 5... Vaporizing glow plug, 5a... Resistor, 5b... Limiting resistor,
5c... Selector switch, 5d... Heater, 6.
...Ignition glow plug, 8...Controller.

Claims (1)

[Claims] In a control device for a combustor that has a vaporizing glow plug and an ignition glow plug, each of which is equipped with a heater having a temperature resistance coefficient, the terminal voltage of a resistor connected in series with the vaporizing glow plug is measured to control the vaporizing glow plug. It comprises a temperature measuring means for measuring temperature, a control means for controlling the energization of the vaporizing glow plug to an appropriate value based on a signal from the temperature measuring means, and a timer for controlling the energization of the ignition glow plug. A control device for a combustor, characterized in that it is provided with energization means for controlling.