JP4255182B2 - Combustion heater system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a combustion heater system that heats engine coolant or intake air to the engine.
[0002]
[Prior art]
In a vehicle equipped with an engine having high combustion efficiency, such as a diesel engine, a combustion heater system is used as an auxiliary heat source for heating the passenger compartment or as an auxiliary machine for warming up the engine during cold start.
For example, Japanese Patent Publication No. 6-13251 describes a vehicle heating device (combustion heater system) that sends combustion gas generated in a combustor of a heater to an intake pipe of the engine when the engine is cold-started. Yes.
[0003]
[Problems to be solved by the invention]
In the above vehicle heating device, when it is not necessary to send combustion gas to the intake pipe of the engine, combustion air is taken into the combustor from another intake passage and the combustion gas is released to the atmosphere. .
Since the pressure loss (flow path resistance) of the intake / exhaust path is different between when warm-up is necessary and when it is not necessary, in the above vehicle heating device, as shown in FIGS. This causes a problem that the air-fuel ratio changes and the exhaust emission increases (CO concentration increases, etc.).
[0004]
A first object of the present invention is to provide a combustion heater system in which exhaust emission does not increase by switching between intake and exhaust paths.
A second object of the present invention is to provide a combustion heater system in which exhaust emission does not increase even if the flow rate ratio of intake and exhaust flowing in each intake and exhaust passage is changed.
[0005]
[Means for Solving the Problems]
[About claim 1]
  The combustion heater system has two or more types of intake and exhaust passages having different pressure losses from the intake port to the exhaust port through the combustion chamber.
  The route selection means selects these intake and exhaust routesThen, an opening signal (open / closed) indicating the selected route is output to the controller.
  In order to supply combustion air and fuel to the combustion chamber, a blower and a fuel pump are provided, and these are controlled by a controller.
[0006]
  When the route selection means changes the intake / exhaust route, Output the opening signal indicating the selected route to the controller,Since the pressure loss in the intake and exhaust passage changes, the controllerUsing the opening signal (open, closed)The energization amount to the blower and the fuel supply capability of the fuel pump, the fuel supply capability of the fuel pump, or the energization amount to the blower are changed.
  ThisGoalSince combustion air of an amount suitable for the combustion amount is supplied to the combustion chamber, the combustion heater system can prevent an increase in exhaust emission due to switching of the intake and exhaust paths.
[0007]
[Claim 2]
  The combustion heater system has two or more types of intake and exhaust passages having different pressure losses from the intake port to the exhaust port through the combustion chamber.
  The flow rate ratio setting means sets the flow rate ratio of the intake / exhaust gas flowing through each intake / exhaust pathWhen the flow rate ratio setting means changes the flow rate ratio, an opening degree signal corresponding to the changed flow rate ratio is output to the controller.
  In order to supply combustion air and fuel to the combustion chamber, a blower and a fuel pump are provided, and these are controlled by a controller.
[0008]
  The flow rate setting means changes the flow rate.And output the opening signal according to the changed flow rate ratio to the controller,Since the pressure loss in the intake and exhaust passage changes, the controllerUsing the opening signal,The energization amount to the blower and the fuel supply capability of the fuel pump, the fuel supply capability of the fuel pump, or the energization amount to the blower are changed.
  AndGoalThe amount of combustion air suitable for the amount of combustionBurnSupply to the firing room.
  ThisGoalSince combustion air of an amount suitable for the combustion amount is supplied to the combustion chamber, the combustion heater system can prevent an increase in exhaust emission due to a change in the flow rate ratio of intake and exhaust flowing in each intake and exhaust passage.
[0009]
[Claim 3]
The combustion of the fuel in the combustion chamber is performed with the target combustion amount calculated from the detected temperature of the working fluid that flows in the fluid passage and is heated by the exhaust, or with the target combustion amount set by the combustion amount setting device. Made.
[0010]
[About claim 4]
  The combustion heater system has two or more types of intake and exhaust passages having different pressure losses from the intake port to the exhaust port through the combustion chamber.
  The route selection meansThe flow rate ratio of intake / exhaust gas flowing through each intake / exhaust path is set, and an opening degree signal corresponding to the changed flow rate ratio is output to the controller.
  A blower and a fuel pump are installed to supply combustion air and fuel to the combustion chamber.These are controlled by a controller.
[0011]
The controller is a target combustion amount set by the combustion amount setting device for setting the combustion amount in the combustion chamber, or a detected temperature of the working fluid that flows in the fluid passage and is heated by the high-temperature exhaust gas generated by the combustion. Based on the target combustion amount calculated from the above, the energization amount to the blower and the fuel supply capability of the fuel pump are determined.
[0012]
  When the route selection means changes the intake / exhaust route, the pressure loss of the intake / exhaust route changes, so among the energization amount to the blower determined by the controller and the fuel supply capacity of the fuel pump,At least oneIs corrected by the correcting means.
  ThisGoalSince combustion air of an amount suitable for the combustion amount is supplied to the combustion chamber, the combustion heater system can prevent an increase in exhaust emission due to switching of the intake and exhaust paths.
[0013]
[About claim 5]
  The combustion heater system has two or more types of intake and exhaust passages having different pressure losses from the intake port to the exhaust port through the combustion chamber.
  The flow rate ratio setting means sets the flow rate ratio of the intake / exhaust gas flowing through each intake / exhaust pathWhen the flow rate ratio setting means changes the flow rate ratio, an opening degree signal corresponding to the changed flow rate ratio is output to the controller.
  In order to supply combustion air and fuel to the combustion chamber, a blower and a fuel pump are provided.
[0014]
  When the flow rate setting means changes the flow rate,An opening signal indicating the selected route is output to the controller.Since the pressure loss in the intake / exhaust passage changes, the controllerUsing the opening signal (open, closed)Current flow to the blowerWhenFuel supply capacity of the fuel pumpChange the fuel supply capacity of the fuel pump or the energization amount to the blower.
  ThisGoalSince combustion air of an amount suitable for the combustion amount is supplied to the combustion chamber, the combustion heater system can prevent an increase in exhaust emission due to a change in the flow rate ratio of intake and exhaust flowing in each intake and exhaust passage.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
The combustion heater system A according to the first embodiment of the present invention (corresponding to claims 1, 2, and 3) includes an intake / exhaust path 1, 2 and an intake / exhaust path 1, 2 as shown in FIGS. An exhaust path switching device 3 for switching the exhaust paths 10 and 20, a blower 4, a fuel pump 5, and a controller 6 that controls the blower 4 and the fuel pump 5 are provided.
[0016]
The intake / exhaust path 1 is a path from the intake port 11 communicating with the engine intake pipe → the intake path 12 → the air blowing chamber 13 → the nozzle 14 → the combustion chamber 15 → the exhaust path 10 → the exhaust port 16 and has a large pressure loss.
When the introduced air (intake air) passes through the intake / exhaust passage 1, the engine cooling water 71 is heated to enhance the capacity of room heating.
[0017]
The exhaust passage 10 is a passage for flowing the high-temperature exhaust gas g and heating the engine cooling water 71 flowing in the engine cooling water passage 7.
A water temperature sensor 72 for detecting the water temperature of the engine cooling water 71 is disposed in the engine cooling water passage 7.
An exhaust passage 10 is provided coaxially so as to surround the combustion chamber 15, and an engine cooling water passage 7 is provided coaxially so as to surround the exhaust passage 10.
[0018]
The intake / exhaust path 2 is a path leading to the intake port 11 communicating with the engine intake pipe → the intake path 12 → the air blowing chamber 13 → the nozzle 14 → the combustion chamber 15 → the exhaust path 20 → the exhaust port 17 communicating with the engine intake pipe. Pressure loss is small.
When the introduced air (intake air) passes through the intake / exhaust passage 2, the startability of the engine can be improved during cold start.
The exhaust passage 20 is a passage for guiding the high-temperature exhaust gas g generated by combustion to the exhaust port 17 as it is.
[0019]
The exhaust passage switching device 3 includes an exhaust switching valve 31 that opens and closes an inlet of the exhaust passage 20 that leads to the rear portion of the combustion chamber 15, and a piston 32 that drives the exhaust switching valve 31 by an actuator (not shown).
[0020]
In this exhaust path switching device 3, when an exhaust path switching signal is sent from an electrical component control ECU (not shown) or the like, the actuator is operated and the exhaust switching valve 31 moves.
Further, an opening degree signal is output from the exhaust path switching device 3 in accordance with the operating state of the actuator.
[0021]
The blower 4 includes a blade 41 disposed in the blower chamber 13 and an air motor 42 for driving the blade 41.
When the air motor 42 is energized, the blades 41 rotate, combustion air is introduced from the intake port 11, and blown out from the nozzle 14 to the combustion chamber 15.
[0022]
The fuel pump 5 is for supplying fuel such as light oil into the combustion chamber 15 via the tube 51, and the fuel supply capacity can be increased or decreased depending on the level of the drive signal.
Reference numeral 52 denotes a glow plug for igniting the fuel supplied into the combustion chamber 15.
[0023]
The controller 6 includes a microcomputer 61, an air motor drive circuit 62, and a fuel pump drive circuit 63.
In this embodiment, as shown in FIG. 3, the microcomputer 61 obtains the temperature of the engine cooling water from the sensor signal output from the water temperature sensor 72, and calculates the water temperature at a predetermined temperature and the detected water temperature required for vehicle interior heating. The fuel supply capacity of the fuel pump 5 is determined by calculating the target combustion amount from the difference. Further, the applied voltage to the air motor 42 is determined from the calculated target combustion amount and the opening degree signal output from the exhaust passage switching device 3.
[0024]
The air motor drive circuit 62 applies the applied voltage determined by the microcomputer 61 to the air motor 42.
The fuel pump drive circuit 63 sends a drive signal at a level at which the fuel supply capability determined by the microcomputer 61 is obtained to the fuel pump 5.
[0025]
Next, the operation of the combustion heater system A will be described.
In cold weather, an electrical component control ECU (not shown) outputs an exhaust path switching signal so that intake / exhaust air flows through the intake / exhaust path 1, and the exhaust switching valve 31 is maintained in a closed state (FIGS. 1 and 3). 4 in the “closed” state).
[0026]
The microcomputer 61 obtains the water temperature of the engine cooling water from the sensor signal output from the water temperature sensor 72, calculates the target combustion amount from the difference between the water temperature at a predetermined temperature required for vehicle interior heating and the like, and the detected water temperature. The fuel supply capacity of the pump 5 is determined. Further, the calculated target combustion amount and an applied voltage that provides a rotational speed at which the combustion air amount necessary for combustion with the target combustion amount (intake and exhaust flows through the intake and exhaust passage 1) can be supplied to the combustion chamber 15. V₁To decide.
[0027]
The air motor drive circuit 62 applies the applied voltage V determined by the microcomputer 61.₁Is applied to the air motor 42.
The fuel pump drive circuit 63 sends a drive signal at a level at which the fuel supply capability determined by the microcomputer 61 is obtained to the fuel pump 5.
[0028]
When the exhaust gas switching valve 31 is in the closed state (the “closed” state in FIGS. 1 and 4), air is introduced from the engine intake pipe through the intake port 11, and the intake passage 12 → the blower chamber 13 → the nozzle 14. To reach the combustion chamber 15. The high-temperature exhaust gas generated by the combustion reaches the exhaust path 10 → the exhaust port 16.
When the exhaust passes through the exhaust passage 10, the engine coolant is heated.
[0029]
When it is necessary to supply high-temperature exhaust gas generated by combustion to the engine, the electrical component control ECU outputs an exhaust path switching signal so that intake / exhaust air flows through the intake / exhaust path 2, thereby The valve 31 changes from closed to open (several tens of seconds from the moment) (a state of “closed” → “open” in FIG. 4), and an opening degree signal is output from the exhaust path switching device 3.
[0030]
Since the engine coolant temperature does not change immediately, the microcomputer 61 calculates the same amount of target combustion and determines the fuel supply capability of the fuel pump 5 to be the same.
Further, based on this target combustion amount and the opening degree signal (closed → open) output from the exhaust path switching device 3, combustion is performed at this target combustion amount (intake and exhaust flow through the intake and exhaust paths 1 and 2). The voltage V applied to the air motor 42 at which the rotational speed at which the necessary combustion air amount can be supplied to the combustion chamber 15 is obtained is determined as needed.
[0031]
The air motor drive circuit 62 applies the applied voltage V (gradual decrease) determined by the microcomputer 61 to the air motor 42.
The fuel pump drive circuit 63 sends to the fuel pump 5 a drive signal of the same level that provides the fuel supply capability of the same capability determined by the microcomputer 61.
[0032]
When the exhaust switching valve 31 is changed (“closed” → “open”), the air introduced from the engine intake pipe through the intake port 11 passes through the intake passage 12 → the blower chamber 13 → the nozzle 14 and the combustion chamber 15. To.
A part of the high-temperature exhaust gas generated by the combustion reaches the exhaust path 10 → the exhaust port 16. Further, the remainder of the high-temperature exhaust reaches the exhaust port 17 that communicates with the exhaust passage 20 → the engine intake pipe.
[0033]
Even if the exhaust gas switching valve 31 completely changes (“opens”), the temperature of the engine coolant does not change immediately. Therefore, the microcomputer 61 calculates the target combustion amount of the same amount and the fuel of the fuel pump 5. The supply capacity is determined to be the same capacity.
Further, on the basis of the target combustion amount and the opening degree signal (open) output from the exhaust passage switching device 3, the combustion required for combustion at this target combustion amount (intake and exhaust flows through the intake and exhaust passage 2). The applied voltage V to the air motor 42 at which the rotational speed at which the amount of air can be supplied to the combustion chamber 15 is obtained.₂To decide.
[0034]
The air motor drive circuit 62 applies the applied voltage V determined by the microcomputer 61.₂Is applied to the air motor 42.
The fuel pump drive circuit 63 sends to the fuel pump 5 a drive signal of the same level that provides the fuel supply capability of the same capability determined by the microcomputer 61.
[0035]
When the exhaust switching valve 31 is completely opened (in the “open” state in FIGS. 2 and 4), the air introduced from the engine intake pipe through the intake port 11 passes through the intake passage 12 → the blower chamber 13 → the nozzle 14. After that, the combustion chamber 15 is reached, and the hot exhaust gas generated by the combustion reaches the exhaust port 17 → the exhaust port 17 communicating with the engine intake pipe.
When the exhaust gas is sent to the engine intake pipe through the exhaust passage 20, the startability of the engine can be improved during the cold start.
[0036]
The combustion heater system A of the present embodiment has the following advantages.
[A] When the exhaust gas passes through the exhaust passage 10 where the pressure loss is large, passes through the exhaust passage 20 where the pressure loss is small, and in the middle of switching from the exhaust passage 10 to the exhaust passage 20, the amount of the exhaust gas is appropriate. Since combustion air is sent into the combustion chamber 15, it is possible to prevent a change in the air-fuel ratio.
For this reason, an increase in CO concentration can be prevented, and an increase in exhaust emission can be suppressed.
[0037]
Next, a combustion type heater system according to a second embodiment of the present invention (corresponding to claims 1, 2, and 3) will be described with reference to FIG. 1, FIG. 2, FIG. 4, and FIG.
The combustion heater system B of the present embodiment is different from the combustion heater system A in the following points.
In the combustion type heater system B of the present embodiment, a combustion amount setting device 70 is disposed on an electrical component operation panel provided at an appropriate position in the vehicle compartment in order to control the combustion amount from the outside.
[0038]
As shown in FIG. 5, the microcomputer 61 determines the fuel supply capability of the fuel pump 5 by calculating the target combustion amount from the combustion amount signal sent from the combustion amount setting device 70. Further, the applied voltage to the air motor 42 is determined from the calculated target combustion amount and the opening degree signal output from the exhaust passage switching device 3.
[0039]
Next, the operation of the combustion heater system B will be described.
In cold weather, the electrical component control ECU outputs an exhaust path switching signal so that intake / exhaust air flows through the intake / exhaust path 1, and the exhaust switching valve 31 is kept closed ("closed" in FIGS. 1 and 4). State).
[0040]
The microcomputer 61 calculates the target combustion amount from the combustion amount signal sent from the combustion amount setting unit 70 and determines the fuel supply capability of the fuel pump 5. Further, the calculated target combustion amount and an applied voltage that provides a rotational speed at which the combustion air amount necessary for combustion with the target combustion amount (intake and exhaust flows through the intake and exhaust passage 1) can be supplied to the combustion chamber 15. V₁To decide.
[0041]
The air motor drive circuit 62 applies the applied voltage V determined by the microcomputer 61.₁Is applied to the air motor 42.
The fuel pump drive circuit 63 sends a drive signal at a level at which the fuel supply capability determined by the microcomputer 61 is obtained to the fuel pump 5.
[0042]
When the exhaust gas switching valve 31 is in the closed state (the “closed” state in FIGS. 1 and 4), air is introduced from the engine intake pipe through the intake port 11, and the intake passage 12 → the blower chamber 13 → the nozzle 14. To reach the combustion chamber 15. The high-temperature exhaust gas generated by the combustion reaches the exhaust path 10 → the exhaust port 16.
When the exhaust passes through the exhaust passage 10, the engine coolant is heated.
[0043]
When it is necessary to supply the engine with high-temperature exhaust gas generated by combustion, the electrical component control ECU outputs an exhaust path switching signal so that intake / exhaust air flows through the intake / exhaust path 2, thereby The valve 31 changes from closed to open (several tens of seconds from the moment) (a state of “closed” → “open” in FIG. 4), and an opening degree signal is output from the exhaust path switching device 3.
[0044]
Since the combustion amount set by the combustion amount setting device does not change, the microcomputer 61 calculates the same amount of target combustion and determines the fuel supply capability of the fuel pump 5 to be the same.
Further, based on this target combustion amount and the opening degree signal (closed → open) output from the exhaust path switching device 3, combustion is performed at this target combustion amount (intake and exhaust flow through the intake and exhaust paths 1 and 2). The voltage V applied to the air motor 42 at which the rotational speed at which the necessary combustion air amount can be supplied to the combustion chamber 15 is obtained is determined as needed.
[0045]
The air motor drive circuit 62 applies the applied voltage V (gradual decrease) determined by the microcomputer 61 to the air motor 42.
The fuel pump drive circuit 63 sends to the fuel pump 5 a drive signal of the same level that provides the fuel supply capability of the same capability determined by the microcomputer 61.
[0046]
When the exhaust switching valve 31 is changed (“closed” → “open”), the air introduced from the engine intake pipe through the intake port 11 passes through the intake passage 12 → the blower chamber 13 → the nozzle 14 and the combustion chamber 15. To.
A part of the high-temperature exhaust gas generated by the combustion reaches the exhaust path 10 → the exhaust port 16. Further, the remainder of the high-temperature exhaust reaches the exhaust port 17 that communicates with the exhaust passage 20 → the engine intake pipe.
[0047]
Even if the exhaust gas switching valve 31 completely changes (“opens”), the combustion amount set by the combustion amount setting device does not change. Therefore, the microcomputer 61 calculates the same target combustion amount and calculates the fuel pump 5. The same fuel supply capacity will be determined.
Further, on the basis of the target combustion amount and the opening degree signal (open) output from the exhaust passage switching device 3, the combustion required for combustion at this target combustion amount (intake and exhaust flows through the intake and exhaust passage 2). The applied voltage V to the air motor 42 at which the rotational speed at which the amount of air can be supplied to the combustion chamber 15 is obtained.₂To decide.
[0048]
The air motor drive circuit 62 applies the applied voltage V determined by the microcomputer 61.₂Is applied to the air motor 42.
The fuel pump drive circuit 63 sends to the fuel pump 5 a drive signal of the same level that provides the fuel supply capability of the same capability determined by the microcomputer 61.
[0049]
When the exhaust switching valve 31 is completely opened (in the “open” state in FIGS. 2 and 4), the air introduced from the engine intake pipe through the intake port 11 passes through the intake passage 12 → the blower chamber 13 → the nozzle 14. After that, the combustion chamber 15 is reached, and the hot exhaust gas generated by the combustion reaches the exhaust port 17 → the exhaust port 17 communicating with the engine intake pipe.
When the exhaust gas is sent to the engine intake pipe through the exhaust passage 20, the startability of the engine can be improved during the cold start.
The combustion heater system B of the present embodiment has the same advantages {advantages according to [A]} as the combustion heater system A.
[0050]
Next, a combustion heater system C according to a third embodiment (corresponding to claims 4 and 5) of the present invention will be described with reference to FIGS. 1, 2, 4, and 6. FIG.
The combustion heater system C of the present embodiment is different from the combustion heater system B in the following points.
In the combustion heater system C, as shown in FIG. 6, the microcomputer 61 calculates the target combustion amount from the combustion amount signal sent from the combustion amount setting device 70, and the fuel pump 5 of the fuel pump 5 is based on this target combustion amount. The fuel supply capacity and the energization amount to the air motor 42 are determined.
Further, an air motor correction amount is calculated (corresponding to a correction amount calculating means) from the calculated target combustion amount and the opening degree signal output from the exhaust passage switching device 3, and the energization amount to the air motor 42 is corrected. Yes.
[0051]
Next, the operation of the combustion heater system C will be described.
In cold weather, the electrical component control ECU outputs an exhaust path switching signal so that intake / exhaust air flows through the intake / exhaust path 1, and the exhaust switching valve 31 is kept closed ("closed" in FIGS. 1 and 4). State).
[0052]
The microcomputer 61 calculates the target combustion amount from the combustion amount signal sent from the combustion amount setting device 70, and determines the fuel supply capability of the fuel pump 5 and the voltage applied to the air motor 42 from this target combustion amount.
Further, the correction amount of the applied voltage is calculated from the combustion amount signal sent from the combustion amount setting device 70 and the opening degree signal output from the exhaust passage switching device 3, and the applied voltage to the air motor 42 is corrected. . By this correction, an applied voltage V that provides a rotational speed at which the amount of combustion air necessary for combustion at the target combustion amount (intake and exhaust flow through the intake and exhaust passage 1) can be supplied to the combustion chamber 15 is obtained.₁It becomes.
[0053]
The air motor drive circuit 62 uses the corrected applied voltage V₁Is applied to the air motor 42.
The fuel pump drive circuit 63 sends a drive signal at a level at which the fuel supply capability determined by the microcomputer 61 is obtained to the fuel pump 5.
[0054]
When it is necessary to reduce the NOx in the exhaust gas of the engine, the electrical component control ECU outputs an exhaust path switching signal so that the intake and exhaust flows through the intake and exhaust path 2, whereby the exhaust switching valve 31 is Then, the state changes from closed to open (several tens of seconds from the moment) (a state of “closed” → “open” in FIG. 4), and an opening degree signal is output from the exhaust path switching device 3.
[0055]
Since the combustion amount set by the combustion amount setting device does not change, the microcomputer 61 calculates the target combustion amount of the same amount, determines the fuel supply capability of the fuel pump 5 to be the same capability, and sets the applied voltage to the same voltage. decide.
Further, the correction amount of the applied voltage is calculated from the target combustion amount and the opening degree signal (closed → open) output from the exhaust passage switching device 3, and the applied voltage to the air motor 42 is corrected. By this correction, the applied voltage to the air motor 42 that provides the number of revolutions required to supply the combustion air amount to the combustion chamber 15 when combustion is performed at this target combustion amount (intake and exhaust flow through the intake and exhaust passages 1 and 2). V.
[0056]
The air motor drive circuit 62 applies the corrected applied voltage V (gradual decrease) to the air motor 42.
The fuel pump drive circuit 63 sends to the fuel pump 5 a drive signal of the same level that provides the fuel supply capability of the same capability determined by the microcomputer 61.
[0057]
Even if the exhaust gas switching valve 31 is completely shifted (“open”), the combustion amount set by the combustion amount setting unit 70 does not change. Therefore, the microcomputer 61 calculates the target combustion amount of the same amount, and the fuel pump 5 is determined to be the same capacity, and the voltage applied to the air motor 42 is determined to be the same voltage.
Further, the correction amount of the applied voltage is calculated from the combustion amount signal sent from the combustion amount setting device 70 and the opening degree signal output from the exhaust passage switching device 3, and the applied voltage to the air motor 42 is corrected. . By this correction, an applied voltage V that provides a rotational speed at which the amount of combustion air necessary for combustion at the target combustion amount (intake and exhaust flow through the intake and exhaust passage 2) can be supplied to the combustion chamber 15 is obtained.₂It becomes.
[0058]
The air motor drive circuit 62 uses the corrected applied voltage V₂Is applied to the air motor 42.
The fuel pump drive circuit 63 sends a drive signal at a level at which the fuel supply capability determined by the microcomputer 61 is obtained to the fuel pump 5.
The combustion heater system C of the present embodiment has the same advantages {advantages according to [A]} as the combustion heater system A.
[0059]
Next, a combustion heater system D according to a fourth embodiment of the present invention (corresponding to claims 1, 2, and 3) will be described with reference to FIG.
The combustion heater system D of the present embodiment is different from the combustion heater system A in the following points.
In the combustion heater system D, an exhaust passage 80 is provided so as to surround the combustion chamber 15, and an engine cooling water passage 7 is provided so as to surround the exhaust passage 80.
That is, the exhaust gas g always flows in the exhaust passage 80 and heats the engine coolant 71 flowing in the engine coolant passage 7.
[0060]
In addition, the combustion heater system D includes an intake / exhaust path (four types) having different pressure losses and an intake / exhaust path switching device 8 for switching each intake / exhaust path separately from the combustion heater main body 100.
[0061]
The intake passage 81 is an intake passage that connects the intake port 811 to the engine intake pipe, and has a small pressure loss.
The intake passage 82 is an intake passage for introducing air outside the vehicle from the intake port 821, and has a large pressure loss because the distance is long.
[0062]
The exhaust path 83 is an exhaust path that connects the exhaust port 831 to the engine intake pipe, and has a small pressure loss. When the exhaust passes through the exhaust passage 83, the startability of the engine can be improved during cold start.
The exhaust path 84 is an exhaust path that connects the exhaust port 841 to the engine exhaust pipe, and has a large pressure loss. When the exhaust passes through the exhaust path 84, the catalyst can be heated to activate the catalyst.
[0063]
The intake / exhaust path switching device 8 for switching between the intake paths 81 and 82 and the exhaust paths 83 and 84 is an intake path switching door 85 disposed on the upstream side of the intake path 12 where the intake path 81 and the intake path 82 merge. And the actuator 851, the exhaust path switching door 86 disposed on the downstream side of the exhaust path 80 where the exhaust path 83 and the exhaust path 84 merge, and the actuator 861.
[0064]
In the intake / exhaust path switching device 8, when an intake / exhaust path switching signal is sent from an electrical component control ECU (not shown) or the like, the actuators 851 and 861 are operated to operate the intake path switching door 85 and the exhaust path switching door 86. Moves.
When supplying high-temperature exhaust gas generated by combustion to the engine, the exhaust path switching door 86 is fixed at the position shown in the solid line in the figure. When the catalyst is regenerated, the exhaust path switching door 86 is switched to the two-dot chain line position by the actuator 861.
The intake path switching door 85 is normally fixed at the position indicated by the solid line in the figure, but when the exhaust path is switched to the exhaust path 84, the actuator 851 reduces the pressure difference with the exhaust port 841. Switch to the dotted line position.
[0065]
In response to the operating state of the actuators 851 and 861, two types of opening degree signals are output from the intake / exhaust passage switching device 8.
[0066]
The controller 6 has a microcomputer, an air motor drive circuit, and a fuel pump drive circuit.
In this embodiment, the microcomputer obtains the temperature of the engine cooling water from the sensor signal output from the water temperature sensor 72, and calculates the target combustion amount from the difference between the water temperature at the predetermined temperature required for vehicle interior heating and the detected water temperature. The fuel supply capacity of the fuel pump 5 is determined by calculation. Further, the applied voltage to the air motor 42 is determined from the calculated target combustion amount and the two kinds of opening degree signals output from the intake / exhaust switching device 8.
[0067]
The air motor drive circuit applies an applied voltage determined by the microcomputer to the air motor 42.
The fuel pump drive circuit sends to the fuel pump 5 a drive signal at a level at which the fuel supply capability determined by the microcomputer can be obtained.
[0068]
The combustion heater system D of the present embodiment has the following advantages.
[A] Even if the intake air is introduced from the intake passage 81 having a small pressure loss, introduced from the intake passage 82 having a large pressure loss, or exhausted from the exhaust passage 83 having a small pressure loss, the pressure loss is large. Even when exhausted from the exhaust path 84 or when these intake and exhaust paths are being switched, an amount of combustion air suitable for the amount of combustion is sent into the combustion chamber 15, thus preventing changes in the air-fuel ratio. it can.
For this reason, an increase in CO concentration can be prevented, and an increase in exhaust emission can be suppressed.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram (exhaust gas switching valve closed) of a combustion heater system according to first to third embodiments of the present invention.
FIG. 2 is an explanatory diagram (exhaust gas switching valve opened) of the combustion heater system according to the first to third embodiments of the present invention.
FIG. 3 is a block diagram of a combustion heater system according to a first embodiment of the present invention.
FIG. 4 is a graph showing changes in the exhaust valve opening, the air motor voltage, and the air supply amount when the exhaust valve is opened from the closed state in the combustion heater system of the present invention.
FIG. 5 is a block diagram of a combustion heater system according to a second embodiment of the present invention.
FIG. 6 is a block diagram of a combustion heater system according to a third embodiment of the present invention.
FIG. 7 is an explanatory diagram of a combustion heater system according to a fourth embodiment of the present invention.
FIG. 8 is a graph showing changes in the exhaust valve opening, the air motor voltage, and the air supply amount when the exhaust valve is opened from the closed state in the conventional combustion heater system.
FIG. 9 is a graph showing the relationship between the air motor voltage and the air supply amount when the exhaust valve is open and when the exhaust valve is closed in the combustion heater system according to the prior art and the present invention.
FIG. 10 is a graph showing CO concentrations when the exhaust valve is opened and when the exhaust valve is closed in the conventional heater system and the combustion heater system according to the present invention.
[Explanation of symbols]
1, 2 intake and exhaust route
3 Exhaust path switching device (path selection means, flow rate ratio setting means)
4 Blowers
5 Fuel pump
6 Controller
8 Intake / exhaust switching device (route selection means, flow rate setting means)
11 Inlet
15 Combustion chamber
16, 17 Exhaust port
70 Combustion amount setting device
A, B, C, D Combustion heater system

Claims (5)

Two or more intake and exhaust passages with different pressure losses from the intake port to the exhaust port through the combustion chamber,
Route selection means for selecting these intake and exhaust routes;
A blower for supplying combustion air to the combustion chamber;
A fuel pump for supplying fuel to the combustion chamber;
In a combustion heater system comprising a controller for controlling the blower and the fuel pump,
When the route selection means changes the intake and exhaust route, an opening signal indicating the selected route is output to the controller,
The controller uses the opening degree signal to change an energization amount to the blower and a fuel supply capability of the fuel pump, a fuel supply capability of the fuel pump, or an energization amount to the blower , and a target combustion amount A combustion heater system, characterized in that an amount of combustion air suitable for the above is supplied to the combustion chamber. Two or more intake and exhaust passages with different pressure losses from the intake port to the exhaust port through the combustion chamber,
A flow rate ratio setting means for setting a flow rate ratio of intake and exhaust flowing through each of these intake and exhaust paths;
A blower for supplying combustion air to the combustion chamber;
A fuel pump for supplying fuel to the combustion chamber;
In a combustion heater system comprising a controller for controlling the blower and the fuel pump,
When the flow rate ratio setting means changes the flow rate ratio, an opening signal corresponding to the changed flow rate ratio is output to the controller,
The controller uses the opening degree signal to change an energization amount to the blower and a fuel supply capability of the fuel pump, a fuel supply capability of the fuel pump, or an energization amount to the blower , and a target combustion amount A combustion heater system, characterized in that an amount of combustion air suitable for the above is supplied to the combustion chamber. The combustion of the fuel in the combustion chamber is performed at a target combustion amount calculated from the detected temperature of the working fluid that flows in the fluid passage and is heated by the exhaust, or a target combustion amount set by a combustion amount setting device The combustion type heater system according to claim 1 or 2 made in the above . Two or more intake and exhaust passages with different pressure losses from the intake port to the exhaust port through the combustion chamber,
Route selection means for selecting these intake and exhaust routes;
A blower for supplying combustion air to the combustion chamber;
A fuel pump for supplying fuel to the combustion chamber;
Based on the target combustion amount set by the combustion amount setting device or the target combustion amount calculated from the detected temperature of the working fluid that flows in the fluid passage and is heated by the exhaust gas, the energization amount to the blower and the fuel of the fuel pump A combustion heater system comprising a controller for determining supply capacity;
When the route selection means changes the intake and exhaust route, an opening signal indicating the selected route is output to the controller,
Correction means for correcting at least one of the energization amount to the blower determined by the controller and the fuel supply capability of the fuel pump is provided, and an amount of combustion air suitable for the combustion amount is supplied to the combustion chamber. Combustion heater system characterized by that. Two or more intake and exhaust passages with different pressure losses from the intake port to the exhaust port through the combustion chamber,
A flow rate ratio setting means for setting a flow rate ratio of intake and exhaust flowing through each of these intake and exhaust paths;
A blower for supplying combustion air to the combustion chamber;
A fuel pump for supplying fuel to the combustion chamber;
Based on the target combustion amount set by the combustion amount setting device or the target combustion amount calculated from the detected temperature of the working fluid that flows in the fluid passage and is heated by the exhaust gas, the energization amount to the blower and the fuel of the fuel pump A combustion heater system comprising a controller for determining supply capacity;
When the flow rate ratio setting means changes the flow rate ratio, an opening signal corresponding to the changed flow rate ratio is output to the controller,
The controller includes correction means for correcting at least one of the energization amount to the blower determined by the controller and the fuel supply capability of the fuel pump using the opening degree signal, and the target combustion amount A combustion heater system, characterized in that an amount of combustion air suitable for the above is supplied to the combustion chamber.

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