WO2020090523A1 - Liquid supply system - Google Patents

Liquid supply system Download PDF

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Publication number
WO2020090523A1
WO2020090523A1 PCT/JP2019/041113 JP2019041113W WO2020090523A1 WO 2020090523 A1 WO2020090523 A1 WO 2020090523A1 JP 2019041113 W JP2019041113 W JP 2019041113W WO 2020090523 A1 WO2020090523 A1 WO 2020090523A1
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WO
WIPO (PCT)
Prior art keywords
liquid supply
unit
charging unit
liquid
charging
Prior art date
Application number
PCT/JP2019/041113
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French (fr)
Japanese (ja)
Inventor
賢吾 古川
勇介 本江
Original Assignee
株式会社デンソー
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Filing date
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Publication of WO2020090523A1 publication Critical patent/WO2020090523A1/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
    • B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
    • B05B5/00—Electrostatic spraying apparatus; Spraying apparatus with means for charging the spray electrically; Apparatus for spraying liquids or other fluent materials by other electric means
    • B05B5/025—Discharge apparatus, e.g. electrostatic spray guns
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous

Definitions

  • the present disclosure relates to a liquid supply system.
  • a liquid supply system that supplies a liquid into the exhaust gas of a combustion engine is known.
  • urea water as a reducing agent is injected and supplied from the injection valve into the exhaust gas to promote purification of the exhaust gas by the NOx catalyst located downstream.
  • An object of the present disclosure is to provide a liquid supply system capable of more homogenizing and supplying a liquid injected into exhaust gas to a catalyst or the like.
  • the present disclosure is a liquid supply system that supplies liquid into exhaust gas of a combustion engine, and includes a liquid supply unit, a first charging unit, and a control unit.
  • the liquid supply unit injects and supplies the liquid into the exhaust gas of the combustion engine.
  • the first charging unit can be charged by applying a voltage and can charge the liquid ejected from the liquid supply unit.
  • the control unit controls the operations of the liquid supply unit and the first charging unit.
  • the control unit can control the operations of the liquid supply unit and the first charging unit to supply the charged liquid to the exhaust gas.
  • the charged liquid is atomized by Coulomb splitting, and the liquid droplets repel each other. Therefore, atomization and homogenization of the liquid spray supplied into the exhaust can be achieved. As described above, the present disclosure can more uniformly supply the liquid injected into the exhaust gas to the catalyst and the like.
  • FIG. 1 is a schematic diagram showing a liquid supply system according to a first embodiment
  • FIG. 2 is a schematic view showing a liquid supply unit of the liquid supply system according to the first embodiment
  • FIG. 3 is a flowchart showing a process regarding control of the liquid supply unit and the first charging unit of the liquid supply system according to the first embodiment
  • FIG. 4 is a graph for explaining the effect of the liquid supply system according to the first embodiment
  • FIG. 5 is a diagram showing the relationship between the ejection pulse and the voltage applied to the charging section in the liquid supply system according to the first embodiment.
  • FIG. 6 is a diagram showing the liquid supply unit of the liquid supply system according to the first embodiment and its vicinity
  • FIG. 7 is a flowchart showing a process relating to control of the liquid supply unit, the first charging unit and the third charging unit of the liquid supply system according to the first embodiment
  • FIG. 8 is a schematic diagram showing the liquid supply unit, the third charging unit, and the vicinity thereof of the liquid supply system according to the second embodiment
  • FIG. 9 is a diagram showing the relationship between the ejection pulse and the voltage applied to the charging section in the liquid supply system according to the third embodiment
  • FIG. 10 is a diagram showing a liquid supply unit of the liquid supply system according to the third embodiment and its vicinity
  • FIG. 11 is a schematic diagram showing a third charging section, a fourth charging section, a catalyst, and the vicinity thereof of the liquid supply system according to the fourth embodiment
  • FIG. 12 is a flowchart showing a process relating to the estimation of the distribution of the reaction substance in the catalyst and the control of the third charging section of the liquid supply system according to the fourth embodiment
  • FIG. 13 is a flowchart showing a process relating to the estimation of the distribution of the reactants on the catalyst in the liquid supply system according to the fourth embodiment.
  • FIG. 14 is a diagram showing the relationship between the temperature difference between the exhaust gas and the catalyst and the amount of the reactant
  • FIG. 15 is a diagram showing a third charging unit and a catalyst of the liquid supply system according to the fourth embodiment
  • FIG. 16 is a diagram showing the relationship between the temperature difference between the exhaust gas and the catalyst and the amount of voltage applied to the third charging section.
  • a liquid supply system will be described below with reference to the drawings.
  • the substantially same components are denoted by the same reference numerals, and the description thereof will be omitted.
  • substantially the same constituent parts have the same or similar action and effect.
  • FIG. 1 A liquid supply system according to the first embodiment is shown in FIG.
  • the liquid supply system 1 is applied to, for example, an exhaust gas purification system 100 for a vehicle (not shown).
  • the exhaust gas purification system 100 includes a catalyst 10.
  • the catalyst 10 is, for example, a NOx catalyst that can purify NOx in exhaust gas.
  • the catalyst 10 is provided in the exhaust pipe 3 through which the exhaust gas discharged from the engine 2 as a combustion engine flows.
  • the liquid supply system 1 supplies urea water as a reducing agent into the exhaust flowing through the exhaust pipe 3.
  • the urea water supplied into the exhaust gas is decomposed into ammonia on the upstream side of the catalyst 10 or inside the catalyst 10.
  • the nitrogen oxides (NOx) in the exhaust gas react with ammonia and are reduced to nitrogen and water.
  • the liquid supplied to the exhaust gas by the liquid supply system 1 is a liquid containing urea or ammonia which is a reaction substance that reacts on the catalyst 10 provided downstream of the liquid supply unit 20. ..
  • the liquid supply system 1 includes a liquid supply unit 20, a first charging unit 311, which is a “charging unit”, a second charging unit 321, a third charging unit 331, which is an “upper charging unit”, and a control unit. It has a section 50 and the like.
  • the liquid supply unit 20 has a main body 21 and injection holes 22.
  • the main body 21 is formed in a tubular shape.
  • the injection hole 22 is formed at one end of the main body 21 and connects the inside and the outside of the main body 21.
  • the liquid supply unit 20 has a needle (not shown). The needle is provided inside the main body 21 so as to be capable of reciprocating, and can open and close the injection hole 22.
  • the control unit 50 is a small computer having a CPU as an arithmetic unit, a ROM and a RAM as a storage unit, an I / O as an input / output unit, and the like.
  • the control unit 50 executes an operation according to a program stored in a ROM or the like on the basis of information such as signals from various sensors provided in each unit of the vehicle to control the operation of various devices and devices of the vehicle. In this way, the control unit 50 executes the program stored in the non-transitional substantive recording medium. By executing this program, the method corresponding to the program is executed.
  • the control unit 50 can control the opening and closing of the injection hole 22 by the needle by controlling the power supply to the liquid supply unit 20. That is, the control unit 50 can control the operation of the liquid supply unit 20.
  • a urea tank (not shown) is connected to the liquid supply unit 20. The urea water stored in the urea tank is supplied to the liquid supply unit 20.
  • the control unit 50 controls the power supply to the liquid supply unit 20, the needle opens and closes the injection hole 22, and the urea water is injected from the injection hole 22.
  • atomized urea water that is, spray, is formed in the vicinity of the injection hole 22 outside the liquid supply unit 20.
  • the liquid supply unit 20 is provided in the exhaust pipe 3 so that the injection hole 22 is exposed in the exhaust pipe 3. Accordingly, the liquid supply unit 20 can inject and supply the urea water into the exhaust gas flowing through the exhaust pipe 3.
  • the liquid supply unit 20 is specifically provided on the upstream side of the exhaust flow with respect to the catalyst 10 (see FIG. 1).
  • the first charging unit 311 is provided integrally with the liquid supply unit 20. Specifically, the first charging section 311 is provided inside the main body 21 of the liquid supply section 20 in the vicinity of the injection hole 22.
  • the first charging unit 311 is positively or negatively charged by applying a voltage.
  • the first charging unit 311 can be charged by applying a voltage, and can charge urea water as a liquid ejected from the liquid supply unit 20.
  • the control unit 50 can control the polarity of the electric charge to be charged in the first charging unit 311 and the amount of the electric charge to be charged by controlling the application of the voltage to the first charging unit 311. That is, the control unit 50 can control the operation of the first charging unit 311.
  • the control unit 50 can control the operations of the liquid supply unit 20 and the first charging unit 311 and supply the charged urea water into the exhaust gas.
  • FIG. 3 A series of processing S100 shown in FIG. 3 is executed, for example, when the ignition key of the vehicle is turned on and the control unit 50 is activated.
  • the control unit 50 receives the urea water injection command. Specifically, for example, the purification rate of the exhaust gas by the catalyst 10 is calculated based on a signal from a NOx sensor provided downstream of the catalyst 10, and when the purification rate is low, an injection command of urea water is received. To do.
  • the injection command corresponds to an injection pulse per injection.
  • control unit 50 starts applying voltage to the first charging unit 311. As a result, the urea water in the liquid supply unit 20 is charged. After S102, the process proceeds to S103.
  • control unit 50 controls the liquid supply unit 20 and starts the injection supply of urea water by the liquid supply unit 20. As a result, the charged urea water is ejected from the liquid supply unit 20. After S103, the process proceeds to S104.
  • control unit 50 stops the injection supply of the urea water from the liquid supply unit 20. Further, at this time, the control unit 50 stops the application of the voltage to the first charging unit 311. As a result, the injection supply from the liquid supply unit 20 of the charged urea water is completed. After S104, the control unit 50 ends the series of processes S100.
  • control unit 50 ends the series of processes S100 and then starts the process S100 again.
  • process S100 is a process that is repeatedly executed during the activation of the control unit 50.
  • FIG. 4 shows the particle diameter ( ⁇ m) and distribution density (%) of the urea water spray when a voltage of 5 kV is applied to the urea water from the first charging unit 311 and when no voltage is applied to the urea water (0 kV). ) Shows the relationship with.
  • FIG. 4 when a voltage of 5 kV is applied from the first charging unit 311 to the urea water, the distribution density of the small particle size is high and the injected urea water is higher than when no voltage is applied to the urea water. It can be seen that atomization is promoted. The atomized droplets repel each other due to the electric charges of the droplets, resulting in further homogenization.
  • the second charging section 321 is provided in the liquid supply section 20. Specifically, the second charging section 321 is provided around the injection hole 22 on the outer wall of the main body 21 of the liquid supply section 20.
  • the second charging unit 321 is charged positively or negatively by applying a voltage.
  • the control unit 50 can control the polarity of the electric charge charged in the second charging unit 321 and the amount of the charged electric charge by controlling the application of the voltage to the second charging unit 321. That is, the control unit 50 can control the operation of the second charging unit 321.
  • the polarity of the electric charges charged in the urea water at the time of spray formation is positive, and the polarity of the electric charges charged in the first charging unit 311 or the second charging unit 321 after the injection period is also positive.
  • repulsive force is generated between the spray of urea water and the first charging unit 311 or the second charging unit 321, and the spray of urea water moves in a direction away from the first charging unit 311 or the second charging unit 321.
  • control unit 50 can control the spray position of the urea water by charging the first charging unit 311 or the second charging unit 321.
  • the urea water is An attractive force is generated between the spray and the first charging unit 311 or the second charging unit 321, and the spray of urea water moves in a direction approaching the first charging unit 311 or the second charging unit 321.
  • control unit 50 charges the first charging unit 311 or the second charging unit 321 with a charge having a polarity opposite to that of the charge charged in the urea water at the time of spray formation after the injection period ends, and thus the urea is charged.
  • An attractive force can be generated between the water spray and the first charging unit 311 or the second charging unit 321.
  • the control unit 50 may, for example, a urea water injection period (t1 to t2) that is a period between the start period (t1) and the end period (t2) of the injection pulse, the first charging unit 311 or A positive voltage is applied to the second charging section 321. As a result, the injected urea spray is charged with a positive charge. Then, the control unit 50 applies a positive voltage to the first charging unit 311 or the second charging unit 321 for a predetermined period (t2 to t3) after the end of the urea water injection period (t1 to t2) from the liquid supply unit 20. Apply. The absolute value of the voltage at this time is higher than the absolute value of the voltage applied to the first charging unit 311 or the second charging unit 321 during the ejection period (t1 to t2).
  • the first charging unit 311 or the second charging unit 321 By applying a positive voltage to the first charging unit 311 or the second charging unit 321 after the injection of the urea water, the first charging unit 311 or the second charging unit 321 is positively charged, and the positive charge is charged. A repulsive force is generated between the spray and the first charging unit 311 or the second charging unit 321. As a result, the urea water spray moves in a direction away from the first charging unit 311 or the second charging unit 321 (see FIG. 6).
  • control unit 50 charges the first charging unit 311 or the second charging unit 321 for a predetermined period after the end of the injection period of the urea water from the liquid supply unit 20 to change the spray position of the urea water. It is controllable. Further, by applying a positive voltage to the first charging unit 311 or the second charging unit 321 after the injection of the urea water, the urea water remaining in the injection hole 22 after the injection can be pushed out, and the post sagging can be suppressed.
  • control unit 50 for example, based on a signal from a sensor (not shown) provided in the exhaust pipe 3, the higher the flow velocity of the exhaust gas, the higher the charge to be charged in the first charging unit 311 or the second charging unit 321 after the end of the injection period. Increase the amount of.
  • the control unit 50 also applies a voltage according to the flow velocity of the exhaust gas to the first charging unit 311 or the second charging unit 321 during the injection period of the urea water from the liquid supply unit 20.
  • the control unit 50 increases the application amount of the voltage applied to the first charging unit 311 or the second charging unit 321 as the flow velocity of the exhaust gas is higher.
  • control unit 50 supplies a voltage corresponding to the temperature of the exhaust gas to the first charging unit 311 based on a signal from a sensor (not shown) provided in the exhaust pipe 3 during the urea water injection period from the liquid supply unit 20. Apply to.
  • the control unit 50 increases the application amount of the voltage applied to the first charging unit 311 as the temperature of the exhaust gas is lower.
  • control unit 50 starts applying the voltage to the first charging unit 311 or the second charging unit 321 before the injection starts, as the injection period of the urea water from the liquid supply unit 20 becomes shorter.
  • control unit 50 does not stop the application of the voltage to the first charging unit 311 or the second charging unit 321 during the period when the frequency of the injection of the urea water from the liquid supply unit 20 becomes the predetermined value or more, continue.
  • the third charging unit 331 is provided in the exhaust pipe 3. Specifically, the third charging unit 331 is provided downstream of the exhaust flow with respect to the liquid supply unit 20 and upstream of the exhaust flow with respect to the catalyst 10.
  • the third charging unit 331 is, for example, formed or arranged in a tubular shape along the exhaust pipe 3.
  • the third charging unit 331 is positively or negatively charged by applying a voltage.
  • the control unit 50 can control the polarity of the electric charge charged in the third charging unit 331, the amount of the charged electric charge, and the like by controlling the application of the voltage to the third charging unit 331. That is, the control unit 50 can control the operation of the third charging unit 331.
  • control unit 50 can control the position of the spray of urea water in the exhaust pipe 3 by charging the third charging unit 331.
  • the control unit 50 charges the third charging unit 331 with a charge having the same polarity as the charge charged in the urea water at the time of forming the spray, thereby causing the urea water to adhere to the inner wall of the exhaust pipe 3. Uneven spraying and deposit formation can be suppressed.
  • FIG. 7 A series of processing S200 shown in FIG. 7 is executed, for example, when the ignition key of the vehicle is turned on and the control unit 50 is activated.
  • control unit 50 jets and supplies the charged urea water from the liquid supply unit 20. Specifically, since it is the same as the process of S100, the description thereof will be omitted. After S201, the process proceeds to S202.
  • the control unit 50 calculates an application period, which is a period in which the voltage is applied to the third charging unit 331, from the flow velocity of exhaust gas. Specifically, the control unit 50 estimates the time for the urea water spray to pass through the third charging unit 331 based on the flow velocity of the exhaust gas, and calculates the application period based on the estimated time. After S202, the process proceeds to S203.
  • control unit 50 applies a voltage to the third charging unit 331. Accordingly, it is possible to suppress the spray of urea water passing through the third charging unit 331 from adhering to the inner wall of the exhaust pipe 3. After S203, the process proceeds to S204.
  • control unit 50 stops applying the voltage to the third charging unit 331 after the application period calculated in S202 ends. After S204, the control unit 50 ends the series of processes S200.
  • the control unit 50 ends the series of processes S200, and then starts the process S200 again.
  • the process S200 is a process that is repeatedly executed during the activation of the control unit 50.
  • the present embodiment is the liquid supply system 1 that supplies the urea water as a liquid into the exhaust gas of the engine 2, and includes the liquid supply unit 20, the first charging unit 311, and the control unit 50. ing.
  • the liquid supply unit 20 injects and supplies urea water into the exhaust gas of the engine 2.
  • the first charging unit 311 can be charged by applying a voltage and can charge the urea water ejected from the liquid supply unit 20.
  • the control unit 50 controls the operations of the liquid supply unit 20 and the first charging unit 311.
  • the control unit 50 can control the operations of the liquid supply unit 20 and the first charging unit 311 to supply the charged urea water into the exhaust gas.
  • the urea water in a charged state is atomized by the division by electrostatic force, that is, Coulomb division. Therefore, the spray of urea water supplied into the exhaust gas can be atomized and further diffused by the charge. As described above, this embodiment can atomize and homogenize the injected urea water. As a result, when urea water as a reducing agent is injected and supplied into the exhaust gas, purification of the exhaust gas by the downstream catalyst 10 can be effectively promoted.
  • the first charging unit 311 is provided integrally with the liquid supply unit 20.
  • the liquid supply system 1 charges the urea water when forming the spray of the urea water. Therefore, it is possible to maximize the effect time of the electrostatic spray such as promotion of atomization during spray formation and diffusion of spray due to Coulomb force.
  • the present embodiment further includes a second charging unit 321.
  • the second charging unit 321 is provided in the liquid supply unit 20 and is charged by applying a voltage.
  • the control unit 50 can control the spray position of the urea water by charging the first charging unit 311 or the second charging unit 321. Therefore, the spray position of the urea water can be controlled only by the first charging unit 311 or the second charging unit 321 provided in the liquid supply unit 20.
  • control unit 50 can control the position of spraying the urea water by charging the first charging unit 311 or the second charging unit 321 for a predetermined period after the end of the injection period of the urea water from the liquid supply unit 20. Is. Therefore, the urea water remaining in the injection hole 22 after the injection can be pushed out, and the post sag can be suppressed.
  • control unit 50 increases the amount of electric charge charged in the first charging unit 311 or the second charging unit 321 after the injection period ends, as the flow velocity of the exhaust gas is higher. Therefore, sufficient penetration force for diffusing the spray with respect to the exhaust flow can be secured.
  • control unit 50 applies the voltage according to the flow rate of the exhaust gas to the first charging unit 311 or the second charging unit 321 during the injection period of the urea water from the liquid supply unit 20. Therefore, the penetration force for diffusing the spray with respect to the exhaust flow can be secured.
  • control unit 50 increases the application amount of the voltage applied to the first charging unit 311 or the second charging unit 321 as the flow velocity of the exhaust gas is higher. Therefore, sufficient penetration force for diffusing the spray with respect to the exhaust flow can be secured.
  • control unit 50 applies the voltage according to the temperature of the exhaust gas to the first charging unit 311 during the injection period of the urea water from the liquid supply unit 20. Therefore, the urea water can be atomized according to the ease of vaporization of the urea water in the exhaust gas.
  • control unit 50 increases the application amount of the voltage applied to the first charging unit 311 as the temperature of the exhaust gas is lower. Therefore, when the temperature of the exhaust gas is low and the vaporization of the urea water is difficult to proceed in the exhaust gas, the spray of the urea water can be atomized, and the vaporization of the urea water can be promoted.
  • control unit 50 applies the voltage to the first charging unit 311 or the second charging unit 321 before the start of injection, as the injection period of the urea water from the liquid supply unit 20 is shorter. To start. Therefore, it is possible to suppress the delay of charging to the spray and secure the electrostatic effect.
  • control unit 50 applies the voltage to the first charging unit 311 or the second charging unit 321 during the period when the frequency of the injection of the urea water from the liquid supply unit 20 is equal to or higher than the predetermined value. continue. Therefore, the delay of charging to the spray can be effectively suppressed and the electrostatic effect can be secured.
  • the present embodiment further includes a third charging unit 331.
  • the third charging unit 331 is provided in the exhaust pipe 3 through which exhaust flows and is charged by applying a voltage.
  • the control unit 50 can control the position of the spray of urea water in the exhaust pipe 3 by charging the third charging unit 331. Therefore, it is possible to prevent the spray of the urea water from adhering to the inner wall of the exhaust pipe 3, and to make the spray uniform and suppress the deposit. Further, it is possible to suppress the density of the spray during the exhaust.
  • the third charging unit 331 is provided downstream of the liquid supply unit 20.
  • the control unit 50 charges the third charging unit 331 with a charge having the same polarity as the charge charged in the urea water during spray formation. Therefore, it is possible to prevent the spray of urea water from adhering to the inner wall of the exhaust pipe 3.
  • control unit 50 applies the voltage to the third charging unit 331 only during the application period which is a predetermined period after the injection of the urea water from the liquid supply unit 20 is started. Therefore, the power consumption of the third charging unit 331 can be suppressed.
  • control unit 50 estimates the time for the urea water spray to pass through the third charging unit 331 based on the flow velocity of the exhaust gas, and calculates the application period based on the estimated time. Therefore, the application time can be set according to the exhaust condition, and the power consumption of the third charging unit 331 can be suppressed more appropriately.
  • FIG. 8 shows a part of the liquid supply system according to the second embodiment.
  • the second embodiment differs from the first embodiment in the configuration of the exhaust pipe 3, the third charging unit 331, and the like.
  • the exhaust pipe 3 has a bent portion 4 that bends from the upstream side to the downstream side of the exhaust flow.
  • the bent portion 4 is formed on the upstream side of the exhaust flow with respect to the third charging portion 331.
  • the liquid supply part 20 is provided upstream of the exhaust flow with respect to the bending part 4.
  • the third charging unit 332 is further provided.
  • the third charging section 332 is provided on the bending section 4.
  • the third charging section 332 has an inner charging section 333 and an outer charging section 334.
  • the inner charging portion 333 is provided inside the bending radius of the bent portion 4 of the exhaust pipe 3.
  • the outer charging portion 334 is provided outside the bending radius of the bent portion 4 of the exhaust pipe 3.
  • the control unit 50 controls the voltage application to the inner charging unit 333 and the outer charging unit 334 of the third charging unit 332 to control the polarity of the charge to be charged to the inner charging unit 333 and the outer charging unit 334, and the charging It is possible to control the amount of electric charges to be generated. That is, the control unit 50 can control the operations of the inner charging unit 333 and the outer charging unit 334.
  • the control unit 50 charges the inner charging unit 333 with a negative charge having a polarity opposite to the positive charge that is the charge charged in the urea water during spray formation, and charges the urea water during the spray formation.
  • the outer charging section 334 is charged with positive charges having the same polarity as the applied charges (see FIG. 8). Therefore, a reaction force acts from the outer charging portion 334, and an attractive force acts from the inner charging portion 333, to the spray of urea water that has passed through the bending portion 4 after being ejected from the liquid supply portion 20. As a result, the spray passes near the center of the exhaust pipe 3 while being subjected to the centrifugal force in the bent portion 4.
  • control unit 50 increases the applied amount of the voltage applied to the inner charging unit 333 and the outer charging unit 334 as the flow velocity of the exhaust gas increases.
  • the third charging portion 332 is provided inside the bending radius of the bent portion 4 of the exhaust pipe 3 and inside the bending radius of the bending portion 4 outside the bending radius of the bending portion 4. It has an outer charging section 334 provided.
  • the control unit 50 charges the inner charging unit 333 with a charge having a polarity opposite to the charge charged in the urea water during spray formation, and charges the outer charging unit with a charge having the same polarity as the charge charged in the urea water during spray formation. 334 is charged.
  • a reaction force acts from the outer charging portion 334, and an attractive force acts from the inner charging portion 333, to the spray of urea water that has passed through the bending portion 4 after being ejected from the liquid supply portion 20.
  • the spray passes near the center of the exhaust pipe 3 while being subjected to the centrifugal force in the bent portion 4.
  • control unit 50 increases the application amount of the voltage applied to the inner charging unit 333 and the outer charging unit 334 as the flow velocity of exhaust gas increases. Therefore, it is possible to effectively suppress uneven spraying at the bent portion 4 due to separation of the flow of exhaust gas or the like.
  • a liquid supply system according to the third embodiment will be described with reference to FIGS.
  • the third embodiment is different from the first embodiment in the configuration of the exhaust pipe 3 and the like.
  • the exhaust pipe 3 has a bent portion 4 that bends from the upstream side to the downstream side of the exhaust flow.
  • the liquid supply part 20 is provided on the upstream side of the exhaust flow with respect to the bending part 4 (see FIG. 10).
  • the liquid supply unit 20 is provided on the upstream side with respect to the portion inside the bending radius of the bending portion 4, and can inject urea water along the direction from the inside of the bending radius of the bending portion 4 to the outside. Is.
  • the control unit 50 may, for example, a urea water injection period (t1 to t2) that is a period between the start (t1) and end (t2) of the injection pulse, the first charging unit 311 or A positive voltage is applied to the second charging section 321. As a result, the injected urea spray is charged with a positive charge. Then, the control unit 50 applies a negative voltage to the first charging unit 311 or the second charging unit 321 for a predetermined period (t2 to t3) after the end of the injection period (t1 to t2) of the urea water from the liquid supply unit 20. Apply. The absolute value of the voltage at this time is higher than the absolute value of the voltage applied to the first charging unit 311 or the second charging unit 321 during the ejection period (t1 to t2).
  • the first charging unit 311 or the second charging unit 321 By applying a negative voltage to the first charging unit 311 or the second charging unit 321 after the injection of the urea water, the first charging unit 311 or the second charging unit 321 is charged with a negative charge and the positive charge is charged. An attractive force is generated between the spray and the first charging unit 311 or the second charging unit 321. As a result, the spray of urea water moves in a direction approaching the first charging unit 311 or the second charging unit 321 (see FIG. 10). As a result, the spray passes near the center of the exhaust pipe 3 while being subjected to the centrifugal force in the bent portion 4. As a result, it is possible to prevent the spray from adhering to the inner wall of the bent portion 4 of the exhaust pipe 3.
  • the control unit 50 causes the first charging unit 311 or the second charging unit 321 to apply a charge having a polarity opposite to the charge charged in the urea water at the time of spray formation. To charge.
  • the spray can be kept in the vicinity of the liquid supply unit 20 in anticipation of the influence of the centrifugal force and the like after the injection.
  • FIG. 11 shows a part of the liquid supply system according to the fourth embodiment.
  • the fourth embodiment differs from the first embodiment in that it further includes a fourth charging section 341 as a “lower charging section”.
  • the present embodiment further includes a fourth charging unit 341 and a detection unit 70.
  • the fourth charging unit 341 is provided in the exhaust pipe 3. Specifically, the fourth charging unit 341 is provided on the downstream side of the exhaust flow with respect to the third charging unit 331 and on the upstream side of the exhaust flow with respect to the catalyst 10.
  • the fourth charging unit 341 is formed, for example, in a circular net shape.
  • the fourth charging unit 341 is positively or negatively charged by applying a voltage.
  • the control unit 50 can control the polarity of the electric charge charged in the fourth charging unit 341, the amount of the charged electric charge, and the like by controlling the voltage application to the fourth charging unit 341. That is, the control unit 50 can control the operation of the fourth charging unit 341.
  • the control unit 50 charges the fourth charging unit 341 with an electric charge having the same polarity as the electric charge charged in the urea water during spray formation, before the spray of urea water passes through the fourth charging unit 341. Therefore, the speed of spraying the urea water decreases due to the repulsive force from the fourth charging unit 341 before passing through the fourth charging unit 341. As a result, it is possible to secure the time for the urea water to vaporize on the upstream side of the catalyst 10 or in the catalyst 10.
  • a plurality of detection units 70 are provided inside the catalyst 10.
  • the detection units 70 are evenly arranged in the radial direction and the circumferential direction of the catalyst 10, for example.
  • the detection unit 70 is, for example, a temperature sensor and can detect the ambient temperature inside the catalyst 10.
  • the detection unit 70 transmits a signal corresponding to the detected temperature to the control unit 50.
  • the control unit 50 can estimate the distribution of the reactant urea or ammonia in the catalyst 10 based on the signals from the plurality of detection units 70.
  • the controller 50 applies a voltage to the third charging unit 331 based on the estimated distribution of the reactant. This makes it possible to control the position of the spray passing through the third charging unit 331 and suppress the uneven distribution of the reactant in the catalyst 10.
  • FIGS. A series of processing S300 shown in FIG. 12 is executed, for example, when the ignition key of the vehicle is turned on and the control unit 50 is activated.
  • control unit 50 estimates the distribution of the reactants in the catalyst 10. Specifically, the control unit 50 estimates the distribution of the reactant in the catalyst 10 by executing the series of processing S400 shown in FIG.
  • control unit 50 acquires the current temperature distribution of the catalyst 10. Specifically, the current temperature distribution of the catalyst 10 is acquired based on the signals from the plurality of detection units 70 provided inside the catalyst 10. After S401, the process proceeds to S402.
  • control unit 50 estimates the distribution of the reactants in the catalyst 10 based on the temperature difference ⁇ T between the exhaust gas and the catalyst 10.
  • the control unit 50 estimates that the larger the temperature difference ⁇ T with the exhaust gas is, the larger the amount of the reactant is, and the distribution of the reactant in the radial direction of the catalyst 10. Is estimated (see FIG. 15). As shown in FIG. 15, it is estimated that the larger the number on the catalyst 10, the larger the amount of the reactant. After S402, the control unit 50 ends S400 and proceeds to S302.
  • control unit 50 determines the direction and size of the electrostatic force to be applied to the catalyst 10 based on the estimated distribution of the reactants in the catalyst 10. After S302, the process proceeds to S302.
  • the control unit 50 applies a voltage to the third charging unit 331 based on the direction and magnitude of the electrostatic force applied to the catalyst 10 determined in S302. Specifically, in the third charging unit 331, the side having a large amount of the reaction substance is charged with a positive charge, and the side having a small amount of the reaction substance is charged with a negative charge. As a result, the spray of urea water having a positive charge moves in the direction in which the distribution of the reactants in the catalyst 10 is small. This makes it possible to control the position of the spray passing through the third charging unit 331 and suppress the uneven distribution of the reactant in the catalyst 10.
  • control unit 50 increases the amount of voltage applied to the third charging unit 331 as the temperature difference from the exhaust gas is larger, that is, the estimated distribution bias is larger. To do. After S303, the control unit 50 ends the series of processes S300.
  • the control unit 50 ends the series of processes S300 after S303, and then starts the process S300 again.
  • the process S300 is a process that is repeatedly executed during the activation of the control unit 50.
  • the liquid ejected from the liquid supply unit 20 is a liquid containing urea or ammonia that is a reaction substance that reacts on the catalyst 10 provided downstream of the liquid supply unit 20. ..
  • the control unit 50 estimates the distribution of the reactant in the radial direction of the catalyst 10, and based on the estimated distribution, the voltage to the third charging unit 331 is adjusted so that the urea water spray moves in the direction in which the distribution of the reactant is small. Control the application of. Thereby, the distribution of the reactants in the catalyst 10 can be made uniform, and the utilization rate of the catalyst 10 can be improved.
  • control unit 50 estimates the distribution of the reactant in the radial direction of the catalyst 10 based on the temperatures detected by the plurality of detection units 70 provided inside the catalyst 10 and capable of detecting the ambient temperature. To do. As described above, in the present embodiment, the distribution of the reactant in the radial direction of the catalyst 10 is estimated based on the reaction heat of the reactant in the catalyst 10.
  • control unit 50 estimates the distribution of the reactants in the radial direction of the catalyst 10, and increases the amount of voltage applied to the third charging unit 331 as the estimated distribution bias increases. Accordingly, it is possible to quickly suppress the uneven distribution of the reactants in the catalyst 10.
  • the present embodiment further includes a fourth charging unit 341.
  • the fourth charging unit 341 is provided on the upstream side of the catalyst 10 provided on the downstream side of the liquid supply unit 20, and is charged by applying a voltage. Therefore, when the fourth charging unit 341 is charged with a charge having the same polarity as the charge charged in the urea water during spray formation, the urea water spray causes the fourth charging unit 341 to pass when passing through the fourth charging unit 341. The repulsive force from reduces the speed. As a result, it is possible to secure the time for the urea water to vaporize on the upstream side of the catalyst 10 or in the catalyst 10.
  • control unit 50 causes the fourth charging unit to apply the charge having the same polarity as the charge charged in the urea water at the time of forming the spray, before the spray of the urea water passes through the fourth charging unit 341. 341 is charged. Therefore, the speed of spraying the urea water decreases due to the repulsive force from the fourth charging unit 341 before passing through the fourth charging unit 341. As a result, it is possible to secure a sufficient time for the urea water to vaporize on the upstream side of the catalyst 10 or on the catalyst 10.
  • the example in which the plurality of detection units 70 capable of detecting the ambient temperature are provided inside the catalyst 10 has been shown.
  • the plurality of detection units 70 capable of detecting the ambient temperature may be provided downstream of the catalyst 10.
  • the plurality of detection units 70 provided inside the catalyst 10 or downstream of the catalyst 10 may be able to detect the concentration of the surrounding nitrogen oxides.
  • the control unit 50 may estimate the distribution of the reactant in the radial direction of the catalyst 10 based on the nitrogen oxide concentrations detected by the plurality of detection units 70. In this way, the distribution of the reactant in the radial direction of the catalyst 10 may be estimated based on the amount of nitrogen oxides purified by the reactant.
  • the plurality of detection units 70 provided inside the catalyst 10 or downstream of the catalyst 10 may be able to detect the concentration of ambient oxygen.
  • the controller 50 may estimate the distribution of the reactant in the radial direction of the catalyst 10 based on the oxygen concentrations detected by the plurality of detectors 70. In this way, the distribution of the reactant in the radial direction of the catalyst 10 may be estimated based on the amount of oxygen that has reacted with the reactant.
  • the plurality of detection units 70 provided inside the catalyst 10 or downstream of the catalyst 10 may be capable of detecting the concentrations of the surrounding reactants.
  • the control unit 50 may estimate the distribution of the reactant in the radial direction of the catalyst 10 based on the concentrations of the reactant detected by the plurality of detectors 70. In this way, the distribution of the reactant in the radial direction of the catalyst 10 may be estimated based on the amount of the reactant.
  • the first charging section may be provided separately from the liquid supply section. Further, in another embodiment, the second charging section may be provided at a position apart from the liquid supply section.
  • urea water is adopted as the liquid supplied from the liquid supply unit 20 into the exhaust gas to promote purification of the exhaust gas with the catalyst 10.
  • hydrocarbon (HC) or the like may be adopted as the liquid supplied from the liquid supply unit 20 into the exhaust gas. In this case, it is possible to increase the temperature by the DOC provided downstream of the liquid supply unit 20 and to regenerate the DPF.
  • the present disclosure is not limited to the above embodiment, and can be implemented in various forms without departing from the gist thereof.

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Abstract

A liquid supply system (1) for supplying a urea water in a liquid state into the exhaust gas of an engine (2), said liquid supply system (1) being provided with a liquid supply unit (20), a first electrification unit (311) and a control unit (50). The liquid supply unit (20) supplies a urea water into the exhaust gas of the engine (2) by spraying. The first electrification unit (311) is charged by the application of a voltage, and is capable of charging the urea water sprayed from the liquid supply unit (20). The control unit (50) controls the operations of the liquid supply unit (20) and the first electrification unit (311). The control unit (50) controls the operations of the liquid supply unit (20) and the first electrification unit (311), thereby making it possible to supply the urea water in a charged state into the exhaust gas.

Description

液体供給システムLiquid supply system 関連出願の相互参照Cross-reference of related applications
　本出願は、２０１８年１０月３０日に出願された特許出願番号２０１８－２０３８７５号に基づくものであり、ここにその記載内容を援用する。 This application is based on the patent application No. 2018-203875 filed on October 30, 2018, the content of which is incorporated herein.
　本開示は、液体供給システムに関する。 The present disclosure relates to a liquid supply system.
　従来、燃焼機関の排気中に液体を供給する液体供給システムが知られている。例えば、特許文献１の液体供給システムでは、還元剤としての尿素水を噴射弁から排気中に噴射供給し、下流のＮＯｘ触媒による排気の浄化を促進している。 Conventionally, a liquid supply system that supplies a liquid into the exhaust gas of a combustion engine is known. For example, in the liquid supply system of Patent Document 1, urea water as a reducing agent is injected and supplied from the injection valve into the exhaust gas to promote purification of the exhaust gas by the NOx catalyst located downstream.
特開２０１８－１１０３号公報JP, 2018-1103, A
　特許文献１の液体供給システムでは、ＮＯｘ触媒による排気の浄化を効果的に行うため、噴射弁から広角かつ均一な噴霧分布を得ることができるよう噴射弁の噴射部周りの構成を工夫している。しかしながら、特許文献１の液体供給システムでは、配管形状や排気流の変化により、触媒到達時に噴霧の偏りが生じるおそれがある。
　本開示の目的は、排気中に噴射する液体を触媒等に、より均質化して供給可能な液体供給システムを提供することにある。 In the liquid supply system of Patent Document 1, in order to effectively purify the exhaust gas with the NOx catalyst, the structure around the injection portion of the injection valve is devised so that a wide-angle and uniform spray distribution can be obtained from the injection valve. .. However, in the liquid supply system of Patent Document 1, there is a possibility that the spray may be biased when reaching the catalyst due to changes in the pipe shape and the exhaust flow.
An object of the present disclosure is to provide a liquid supply system capable of more homogenizing and supplying a liquid injected into exhaust gas to a catalyst or the like.
　本開示は、燃焼機関の排気中に液体を供給する液体供給システムであって、液体供給部と第１帯電部と制御部とを備えている。液体供給部は、燃焼機関の排気中に液体を噴射供給する。第１帯電部は、電圧の印加により帯電し、液体供給部から噴射される液体を帯電させることが可能である。制御部は、液体供給部および第１帯電部の作動を制御する。制御部は、液体供給部および第１帯電部の作動を制御し、帯電した状態の液体を排気中に供給することが可能である。 The present disclosure is a liquid supply system that supplies liquid into exhaust gas of a combustion engine, and includes a liquid supply unit, a first charging unit, and a control unit. The liquid supply unit injects and supplies the liquid into the exhaust gas of the combustion engine. The first charging unit can be charged by applying a voltage and can charge the liquid ejected from the liquid supply unit. The control unit controls the operations of the liquid supply unit and the first charging unit. The control unit can control the operations of the liquid supply unit and the first charging unit to supply the charged liquid to the exhaust gas.
　本開示では、帯電した状態の液体は、クーロン***により微粒化し、液滴同士が反発する。そのため、排気中に供給する液体の噴霧を微粒化および均質化できる。このように、本開示は、排気中に噴射する液体を触媒等に、より均質に供給可能である。 In the present disclosure, the charged liquid is atomized by Coulomb splitting, and the liquid droplets repel each other. Therefore, atomization and homogenization of the liquid spray supplied into the exhaust can be achieved. As described above, the present disclosure can more uniformly supply the liquid injected into the exhaust gas to the catalyst and the like.
　本開示についての上記目的およびその他の目的、特徴や利点は、添付の図面を参照しながら下記の詳細な記述により、より明確になる。その図面は、
図１は、第１実施形態による液体供給システムを示す模式図であり、 図２は、第１実施形態による液体供給システムの液体供給部を示す模式図であり、 図３は、第１実施形態による液体供給システムの液体供給部および第１帯電部の制御に関する処理を示すフローチャートであり、 図４は、第１実施形態による液体供給システムの効果を説明するためのグラフであり、 図５は、第１実施形態による液体供給システムにおける噴射パルスと帯電部への印加電圧との関係を示す図であり、 図６は、第１実施形態による液体供給システムの液体供給部、および、その近傍を示す図であり、 図７は、第１実施形態による液体供給システムの液体供給部、第１帯電部および第３帯電部の制御に関する処理を示すフローチャートであり、 図８は、第２実施形態による液体供給システムの液体供給部、第３帯電部、および、その近傍を示す模式図であり、 図９は、第３実施形態による液体供給システムにおける噴射パルスと帯電部への印加電圧との関係を示す図であり、 図１０は、第３実施形態による液体供給システムの液体供給部、および、その近傍を示す図であり、 図１１は、第４実施形態による液体供給システムの第３帯電部、第４帯電部、触媒、および、その近傍を示す模式図であり、 図１２は、第４実施形態による液体供給システムの、触媒における反応物質の分布の推定、および、第３帯電部の制御に関する処理を示すフローチャートであり、 図１３は、第４実施形態による液体供給システムの、触媒における反応物質の分布の推定に関する処理を示すフローチャートであり、 図１４は、排気と触媒との温度差と反応物質の量との関係を示す図であり、 図１５は、第４実施形態による液体供給システムの第３帯電部および触媒を示す図であり、 図１６は、排気と触媒との温度差と、第３帯電部への電圧の印加量との関係を示す図である。 The above and other objects, features and advantages of the present disclosure will become more apparent by the following detailed description with reference to the accompanying drawings. The drawing is
FIG. 1 is a schematic diagram showing a liquid supply system according to a first embodiment, FIG. 2 is a schematic view showing a liquid supply unit of the liquid supply system according to the first embodiment, FIG. 3 is a flowchart showing a process regarding control of the liquid supply unit and the first charging unit of the liquid supply system according to the first embodiment, FIG. 4 is a graph for explaining the effect of the liquid supply system according to the first embodiment, FIG. 5 is a diagram showing the relationship between the ejection pulse and the voltage applied to the charging section in the liquid supply system according to the first embodiment. FIG. 6 is a diagram showing the liquid supply unit of the liquid supply system according to the first embodiment and its vicinity, FIG. 7 is a flowchart showing a process relating to control of the liquid supply unit, the first charging unit and the third charging unit of the liquid supply system according to the first embodiment, FIG. 8 is a schematic diagram showing the liquid supply unit, the third charging unit, and the vicinity thereof of the liquid supply system according to the second embodiment, FIG. 9 is a diagram showing the relationship between the ejection pulse and the voltage applied to the charging section in the liquid supply system according to the third embodiment, FIG. 10 is a diagram showing a liquid supply unit of the liquid supply system according to the third embodiment and its vicinity, FIG. 11 is a schematic diagram showing a third charging section, a fourth charging section, a catalyst, and the vicinity thereof of the liquid supply system according to the fourth embodiment, FIG. 12 is a flowchart showing a process relating to the estimation of the distribution of the reaction substance in the catalyst and the control of the third charging section of the liquid supply system according to the fourth embodiment. FIG. 13 is a flowchart showing a process relating to the estimation of the distribution of the reactants on the catalyst in the liquid supply system according to the fourth embodiment. FIG. 14 is a diagram showing the relationship between the temperature difference between the exhaust gas and the catalyst and the amount of the reactant, FIG. 15 is a diagram showing a third charging unit and a catalyst of the liquid supply system according to the fourth embodiment, FIG. 16 is a diagram showing the relationship between the temperature difference between the exhaust gas and the catalyst and the amount of voltage applied to the third charging section.
　以下、複数の実施形態による液体供給システムを図面に基づき説明する。なお、複数の実施形態において実質的に同一の構成部位には同一の符号を付し、説明を省略する。また、複数の実施形態において実質的に同一の構成部位は、同一または同様の作用効果を奏する。 A liquid supply system according to a plurality of embodiments will be described below with reference to the drawings. In addition, in a plurality of embodiments, the substantially same components are denoted by the same reference numerals, and the description thereof will be omitted. Further, in the plurality of embodiments, substantially the same constituent parts have the same or similar action and effect.
　　（第１実施形態）
　第１実施形態による液体供給システムを図１に示す。液体供給システム１は、例えば図示しない車両の排気浄化システム１００に適用される。排気浄化システム１００は、触媒１０を備えている。触媒１０は、例えば、排気中のＮＯｘを浄化可能なＮＯｘ触媒である。触媒１０は、燃焼機関としてのエンジン２から排出される排気が流れる排気管３に設けられる。 (First embodiment)
A liquid supply system according to the first embodiment is shown in FIG. The liquid supply system 1 is applied to, for example, an exhaust gas purification system 100 for a vehicle (not shown). The exhaust gas purification system 100 includes a catalyst 10. The catalyst 10 is, for example, a NOx catalyst that can purify NOx in exhaust gas. The catalyst 10 is provided in the exhaust pipe 3 through which the exhaust gas discharged from the engine 2 as a combustion engine flows.
　液体供給システム１は、排気管３を流れる排気中に還元剤としての尿素水を供給する。排気中に供給された尿素水は、触媒１０の上流側または触媒１０内においてアンモニアに分解される。これにより、排気中の窒素酸化物（ＮＯｘ）がアンモニアと反応することで、窒素と水に還元される。このように、本実施形態では、液体供給システム１が排気中に供給する液体は、液体供給部２０の下流に設けられた触媒１０上で反応する反応物質である尿素またはアンモニアを含む液体である。 The liquid supply system 1 supplies urea water as a reducing agent into the exhaust flowing through the exhaust pipe 3. The urea water supplied into the exhaust gas is decomposed into ammonia on the upstream side of the catalyst 10 or inside the catalyst 10. As a result, the nitrogen oxides (NOx) in the exhaust gas react with ammonia and are reduced to nitrogen and water. As described above, in the present embodiment, the liquid supplied to the exhaust gas by the liquid supply system 1 is a liquid containing urea or ammonia which is a reaction substance that reacts on the catalyst 10 provided downstream of the liquid supply unit 20. ..
　図１に示すように、液体供給システム１は、液体供給部２０、「帯電部」としての第１帯電部３１１、第２帯電部３２１、「上帯電部」としての第３帯電部３３１、制御部５０等を備えている。図２に示すように、液体供給部２０は、本体２１、噴孔２２を有している。本体２１は、筒状に形成されている。噴孔２２は、本体２１の一方の端部に形成され、本体２１の内部と外部とを連通している。液体供給部２０は、図示しないニードルを有している。ニードルは、本体２１の内側において往復移動可能に設けられ、噴孔２２を開閉可能である。 As shown in FIG. 1, the liquid supply system 1 includes a liquid supply unit 20, a first charging unit 311, which is a “charging unit”, a second charging unit 321, a third charging unit 331, which is an “upper charging unit”, and a control unit. It has a section 50 and the like. As shown in FIG. 2, the liquid supply unit 20 has a main body 21 and injection holes 22. The main body 21 is formed in a tubular shape. The injection hole 22 is formed at one end of the main body 21 and connects the inside and the outside of the main body 21. The liquid supply unit 20 has a needle (not shown). The needle is provided inside the main body 21 so as to be capable of reciprocating, and can open and close the injection hole 22.
　制御部５０は、演算手段としてのＣＰＵ、記憶手段としてのＲＯＭ、ＲＡＭ、入出力手段としてのＩ／Ｏ等を有する小型のコンピュータである。制御部５０は、車両の各部に設けられた各種センサからの信号等の情報に基づき、ＲＯＭ等に格納されたプログラムに従い演算を実行し、車両の各種装置および機器の作動を制御する。このように、制御部５０は、非遷移的実体的記録媒体に格納されたプログラムを実行する。このプログラムが実行されることで、プログラムに対応する方法が実行される。 The control unit 50 is a small computer having a CPU as an arithmetic unit, a ROM and a RAM as a storage unit, an I / O as an input / output unit, and the like. The control unit 50 executes an operation according to a program stored in a ROM or the like on the basis of information such as signals from various sensors provided in each unit of the vehicle to control the operation of various devices and devices of the vehicle. In this way, the control unit 50 executes the program stored in the non-transitional substantive recording medium. By executing this program, the method corresponding to the program is executed.
　制御部５０は、液体供給部２０への通電を制御することにより、ニードルによる噴孔２２の開閉を制御可能である。すなわち、制御部５０は、液体供給部２０の作動を制御可能である。液体供給部２０には、図示しない尿素タンクが接続されている。尿素タンクに貯留された尿素水は、液体供給部２０に供給される。制御部５０が液体供給部２０への通電を制御すると、ニードルが噴孔２２を開閉し、噴孔２２から尿素水が噴射される。これにより、液体供給部２０の外部の噴孔２２近傍には、霧状の尿素水、すなわち、噴霧が形成される。 The control unit 50 can control the opening and closing of the injection hole 22 by the needle by controlling the power supply to the liquid supply unit 20. That is, the control unit 50 can control the operation of the liquid supply unit 20. A urea tank (not shown) is connected to the liquid supply unit 20. The urea water stored in the urea tank is supplied to the liquid supply unit 20. When the control unit 50 controls the power supply to the liquid supply unit 20, the needle opens and closes the injection hole 22, and the urea water is injected from the injection hole 22. As a result, atomized urea water, that is, spray, is formed in the vicinity of the injection hole 22 outside the liquid supply unit 20.
　液体供給部２０は、噴孔２２が排気管３内に露出するよう排気管３に設けられる。これにより、液体供給部２０は、排気管３を流れる排気中に尿素水を噴射供給可能である。液体供給部２０は、具体的には、触媒１０に対し排気流れの上流側に設けられる（図１参照）。 The liquid supply unit 20 is provided in the exhaust pipe 3 so that the injection hole 22 is exposed in the exhaust pipe 3. Accordingly, the liquid supply unit 20 can inject and supply the urea water into the exhaust gas flowing through the exhaust pipe 3. The liquid supply unit 20 is specifically provided on the upstream side of the exhaust flow with respect to the catalyst 10 (see FIG. 1).
　図２に示すように、第１帯電部３１１は、液体供給部２０と一体に設けられている。具体的には、第１帯電部３１１は、液体供給部２０の本体２１の内側において噴孔２２の近傍に設けられている。第１帯電部３１１は、電圧の印加により正または負に帯電する。第１帯電部３１１は、電圧の印加により帯電し、液体供給部２０から噴射される液体としての尿素水を帯電させることが可能である。 As shown in FIG. 2, the first charging unit 311 is provided integrally with the liquid supply unit 20. Specifically, the first charging section 311 is provided inside the main body 21 of the liquid supply section 20 in the vicinity of the injection hole 22. The first charging unit 311 is positively or negatively charged by applying a voltage. The first charging unit 311 can be charged by applying a voltage, and can charge urea water as a liquid ejected from the liquid supply unit 20.
　制御部５０は、第１帯電部３１１への電圧の印加を制御することにより、第１帯電部３１１に帯電させる電荷の極性、および、帯電させる電荷の量等を制御可能である。すなわち、制御部５０は、第１帯電部３１１の作動を制御可能である。 The control unit 50 can control the polarity of the electric charge to be charged in the first charging unit 311 and the amount of the electric charge to be charged by controlling the application of the voltage to the first charging unit 311. That is, the control unit 50 can control the operation of the first charging unit 311.
　制御部５０は、液体供給部２０および第１帯電部３１１の作動を制御し、帯電した状態の尿素水を排気中に供給することが可能である。 The control unit 50 can control the operations of the liquid supply unit 20 and the first charging unit 311 and supply the charged urea water into the exhaust gas.
　次に、本実施形態の制御部５０による液体供給部２０および第１帯電部３１１の制御に関する処理について、図３に基づき説明する。図３に示す一連の処理Ｓ１００は、例えば車両のイグニッションキーがオンされ制御部５０が起動すると実行される。 Next, a process regarding control of the liquid supply unit 20 and the first charging unit 311 by the control unit 50 of the present embodiment will be described based on FIG. A series of processing S100 shown in FIG. 3 is executed, for example, when the ignition key of the vehicle is turned on and the control unit 50 is activated.
　Ｓ１０１では、制御部５０は、尿素水の噴射指令を受領する。具体的には、例えば、触媒１０の下流に設けたＮＯｘセンサからの信号等に基づき、触媒１０による排気の浄化率を算出し、浄化率が低下していた場合、尿素水の噴射指令を受領する。ここで、噴射指令は、噴射１回あたりの噴射パルスに相当する。Ｓ１０１の後、処理はＳ１０２へ移行する。 In S101, the control unit 50 receives the urea water injection command. Specifically, for example, the purification rate of the exhaust gas by the catalyst 10 is calculated based on a signal from a NOx sensor provided downstream of the catalyst 10, and when the purification rate is low, an injection command of urea water is received. To do. Here, the injection command corresponds to an injection pulse per injection. After S101, the process proceeds to S102.
　Ｓ１０２では、制御部５０は、第１帯電部３１１への電圧の印加を開始する。これにより、液体供給部２０内の尿素水が帯電する。Ｓ１０２の後、処理はＳ１０３へ移行する。 In S102, the control unit 50 starts applying voltage to the first charging unit 311. As a result, the urea water in the liquid supply unit 20 is charged. After S102, the process proceeds to S103.
　Ｓ１０３では、制御部５０は、液体供給部２０を制御し、液体供給部２０による尿素水の噴射供給を開始する。これにより、帯電した尿素水が液体供給部２０から噴射される。Ｓ１０３の後、処理はＳ１０４へ移行する。 In S103, the control unit 50 controls the liquid supply unit 20 and starts the injection supply of urea water by the liquid supply unit 20. As a result, the charged urea water is ejected from the liquid supply unit 20. After S103, the process proceeds to S104.
　Ｓ１０４では、制御部５０は、液体供給部２０からの尿素水の噴射供給を停止する。また、このとき、制御部５０は、第１帯電部３１１への電圧の印加を停止する。これにより、帯電した尿素水の液体供給部２０からの噴射供給が終了する。Ｓ１０４の後、制御部５０は、一連の処理Ｓ１００を終了する。 In S104, the control unit 50 stops the injection supply of the urea water from the liquid supply unit 20. Further, at this time, the control unit 50 stops the application of the voltage to the first charging unit 311. As a result, the injection supply from the liquid supply unit 20 of the charged urea water is completed. After S104, the control unit 50 ends the series of processes S100.
　制御部５０は、Ｓ１０４の後、一連の処理Ｓ１００を終了し、その後、再び処理Ｓ１００を開始する。このように、処理Ｓ１００は、制御部５０の起動中、繰り返し実行される処理である。 After S104, the control unit 50 ends the series of processes S100 and then starts the process S100 again. As described above, the process S100 is a process that is repeatedly executed during the activation of the control unit 50.
　次に、噴射する尿素水に帯電させることによる効果について、説明する。帯電した状態の尿素水は、静電力による***、すなわち、クーロン***により微粒化する。図４に、第１帯電部３１１から尿素水に５ｋＶの電圧を印加した場合、および、尿素水に電圧を印加しない場合（０ｋＶ）の尿素水の噴霧の粒径（μｍ）と分布密度（％）との関係を示す。図４に示すように、第１帯電部３１１から尿素水に５ｋＶの電圧を印加した場合、尿素水に電圧を印加しない場合と比べ、小さな粒径の分布密度が高く、噴射された尿素水の微粒化が促進されていることがわかる。この微粒化した液滴が、各々が持つ電荷により反発し合い、より均質化が進む。 Next, the effect of charging the injected urea water will be explained. The urea water in the charged state is atomized by the splitting due to electrostatic force, that is, Coulomb splitting. FIG. 4 shows the particle diameter (μm) and distribution density (%) of the urea water spray when a voltage of 5 kV is applied to the urea water from the first charging unit 311 and when no voltage is applied to the urea water (0 kV). ) Shows the relationship with. As shown in FIG. 4, when a voltage of 5 kV is applied from the first charging unit 311 to the urea water, the distribution density of the small particle size is high and the injected urea water is higher than when no voltage is applied to the urea water. It can be seen that atomization is promoted. The atomized droplets repel each other due to the electric charges of the droplets, resulting in further homogenization.
　図２に示すように、第２帯電部３２１は、液体供給部２０に設けられている。具体的には、第２帯電部３２１は、液体供給部２０の本体２１の外壁において噴孔２２の周囲に設けられている。第２帯電部３２１は、電圧の印加により正または負に帯電する。 As shown in FIG. 2, the second charging section 321 is provided in the liquid supply section 20. Specifically, the second charging section 321 is provided around the injection hole 22 on the outer wall of the main body 21 of the liquid supply section 20. The second charging unit 321 is charged positively or negatively by applying a voltage.
　制御部５０は、第２帯電部３２１への電圧の印加を制御することにより、第２帯電部３２１に帯電させる電荷の極性、および、帯電させる電荷の量等を制御可能である。すなわち、制御部５０は、第２帯電部３２１の作動を制御可能である。 The control unit 50 can control the polarity of the electric charge charged in the second charging unit 321 and the amount of the charged electric charge by controlling the application of the voltage to the second charging unit 321. That is, the control unit 50 can control the operation of the second charging unit 321.
　図２に示すように、例えば、噴霧形成時に尿素水に帯電させた電荷の極性が正であり、噴射期間終了後に第１帯電部３１１または第２帯電部３２１に帯電させた電荷の極性も正の場合、尿素水の噴霧と第１帯電部３１１または第２帯電部３２１との間には斥力が生じ、尿素水の噴霧は、第１帯電部３１１または第２帯電部３２１から遠ざかる方向に移動する。 As shown in FIG. 2, for example, the polarity of the electric charges charged in the urea water at the time of spray formation is positive, and the polarity of the electric charges charged in the first charging unit 311 or the second charging unit 321 after the injection period is also positive. In the case of, repulsive force is generated between the spray of urea water and the first charging unit 311 or the second charging unit 321, and the spray of urea water moves in a direction away from the first charging unit 311 or the second charging unit 321. To do.
　このように、制御部５０は、第１帯電部３１１または第２帯電部３２１を帯電させることで、尿素水の噴霧の位置を制御可能である。 In this way, the control unit 50 can control the spray position of the urea water by charging the first charging unit 311 or the second charging unit 321.
　また、例えば、噴霧形成時に尿素水に帯電させた電荷の極性が正であり、噴射期間終了後に第１帯電部３１１または第２帯電部３２１に帯電させた電荷の極性が負の場合、尿素水の噴霧と第１帯電部３１１または第２帯電部３２１との間には引力が生じ、尿素水の噴霧は、第１帯電部３１１または第２帯電部３２１に近付く方向に移動する。 In addition, for example, when the polarity of the electric charge charged in the urea water during spray formation is positive and the polarity of the electric charge charged in the first charging unit 311 or the second charging unit 321 after the injection period is negative, the urea water is An attractive force is generated between the spray and the first charging unit 311 or the second charging unit 321, and the spray of urea water moves in a direction approaching the first charging unit 311 or the second charging unit 321.
　このように、制御部５０は、噴射期間終了後、噴霧形成時に尿素水に帯電させた電荷とは逆の極性の電荷を第１帯電部３１１または第２帯電部３２１に帯電させることで、尿素水の噴霧と第１帯電部３１１または第２帯電部３２１との間に引力を生じさせることができる。 In this way, the control unit 50 charges the first charging unit 311 or the second charging unit 321 with a charge having a polarity opposite to that of the charge charged in the urea water at the time of spray formation after the injection period ends, and thus the urea is charged. An attractive force can be generated between the water spray and the first charging unit 311 or the second charging unit 321.
　図５に示すように、制御部５０は、例えば、噴射パルスの始期（ｔ１）と終期（ｔ２）との間の期間である尿素水の噴射期間（ｔ１～ｔ２）、第１帯電部３１１または第２帯電部３２１に正の電圧を印加する。これにより、噴射される尿素の噴霧には、正の電荷が帯電する。そして、制御部５０は、液体供給部２０からの尿素水の噴射期間（ｔ１～ｔ２）終了後の所定期間（ｔ２～ｔ３）、第１帯電部３１１または第２帯電部３２１に正の電圧を印加する。なお、このときの電圧の絶対値は、噴射期間（ｔ１～ｔ２）に第１帯電部３１１または第２帯電部３２１に印加した電圧の絶対値よりも高い。 As shown in FIG. 5, the control unit 50 may, for example, a urea water injection period (t1 to t2) that is a period between the start period (t1) and the end period (t2) of the injection pulse, the first charging unit 311 or A positive voltage is applied to the second charging section 321. As a result, the injected urea spray is charged with a positive charge. Then, the control unit 50 applies a positive voltage to the first charging unit 311 or the second charging unit 321 for a predetermined period (t2 to t3) after the end of the urea water injection period (t1 to t2) from the liquid supply unit 20. Apply. The absolute value of the voltage at this time is higher than the absolute value of the voltage applied to the first charging unit 311 or the second charging unit 321 during the ejection period (t1 to t2).
　尿素水の噴射後に第１帯電部３１１または第２帯電部３２１に正の電圧を印加することで、第１帯電部３１１または第２帯電部３２１に正の電荷が帯電し、正の電荷が帯電した噴霧と第１帯電部３１１または第２帯電部３２１との間に斥力が生じる。これにより、尿素水の噴霧は、第１帯電部３１１または第２帯電部３２１から離れる方向に移動する（図６参照）。 By applying a positive voltage to the first charging unit 311 or the second charging unit 321 after the injection of the urea water, the first charging unit 311 or the second charging unit 321 is positively charged, and the positive charge is charged. A repulsive force is generated between the spray and the first charging unit 311 or the second charging unit 321. As a result, the urea water spray moves in a direction away from the first charging unit 311 or the second charging unit 321 (see FIG. 6).
　このように、制御部５０は、液体供給部２０からの尿素水の噴射期間終了後の所定期間、第１帯電部３１１または第２帯電部３２１を帯電させることで、尿素水の噴霧の位置を制御可能である。また、尿素水の噴射後に第１帯電部３１１または第２帯電部３２１に正の電圧を印加することで、噴射後の噴孔２２内に残留した尿素水を押し出し、後ダレを抑制できる。 As described above, the control unit 50 charges the first charging unit 311 or the second charging unit 321 for a predetermined period after the end of the injection period of the urea water from the liquid supply unit 20 to change the spray position of the urea water. It is controllable. Further, by applying a positive voltage to the first charging unit 311 or the second charging unit 321 after the injection of the urea water, the urea water remaining in the injection hole 22 after the injection can be pushed out, and the post sagging can be suppressed.
　また、制御部５０は、例えば排気管３に設けた図示しないセンサからの信号等に基づき、排気の流速が高い程、噴射期間終了後に第１帯電部３１１または第２帯電部３２１に帯電させる電荷の量を大きくする。 Further, the control unit 50, for example, based on a signal from a sensor (not shown) provided in the exhaust pipe 3, the higher the flow velocity of the exhaust gas, the higher the charge to be charged in the first charging unit 311 or the second charging unit 321 after the end of the injection period. Increase the amount of.
　また、制御部５０は、液体供給部２０からの尿素水の噴射期間中、排気の流速に応じた電圧を第１帯電部３１１または第２帯電部３２１に印加する。ここで、制御部５０は、排気の流速が高い程、第１帯電部３１１または第２帯電部３２１に印加する電圧の印加量を大きくする。 The control unit 50 also applies a voltage according to the flow velocity of the exhaust gas to the first charging unit 311 or the second charging unit 321 during the injection period of the urea water from the liquid supply unit 20. Here, the control unit 50 increases the application amount of the voltage applied to the first charging unit 311 or the second charging unit 321 as the flow velocity of the exhaust gas is higher.
　また、制御部５０は、液体供給部２０からの尿素水の噴射期間中、例えば排気管３に設けた図示しないセンサからの信号等に基づき、排気の温度に応じた電圧を第１帯電部３１１に印加する。ここで、制御部５０は、排気の温度が低い程、第１帯電部３１１に印加する電圧の印加量を大きくする。 Further, the control unit 50 supplies a voltage corresponding to the temperature of the exhaust gas to the first charging unit 311 based on a signal from a sensor (not shown) provided in the exhaust pipe 3 during the urea water injection period from the liquid supply unit 20. Apply to. Here, the control unit 50 increases the application amount of the voltage applied to the first charging unit 311 as the temperature of the exhaust gas is lower.
　また、制御部５０は、液体供給部２０からの尿素水の噴射期間が短い程、噴射開始よりも前に、第１帯電部３１１または第２帯電部３２１への電圧の印加を開始する。 Further, the control unit 50 starts applying the voltage to the first charging unit 311 or the second charging unit 321 before the injection starts, as the injection period of the urea water from the liquid supply unit 20 becomes shorter.
　また、制御部５０は、液体供給部２０からの尿素水の噴射の頻度が所定値以上となる期間中、第１帯電部３１１または第２帯電部３２１への電圧の印加を停止することなく、継続する。 In addition, the control unit 50 does not stop the application of the voltage to the first charging unit 311 or the second charging unit 321 during the period when the frequency of the injection of the urea water from the liquid supply unit 20 becomes the predetermined value or more, continue.
　図１に示すように、第３帯電部３３１は、排気管３に設けられる。具体的には、第３帯電部３３１は、液体供給部２０に対し排気流れの下流側であって、触媒１０に対し排気流れの上流側に設けられる。第３帯電部３３１は、例えば、排気管３に沿って筒状に形成または配置されている。第３帯電部３３１は、電圧の印加により正または負に帯電する。 As shown in FIG. 1, the third charging unit 331 is provided in the exhaust pipe 3. Specifically, the third charging unit 331 is provided downstream of the exhaust flow with respect to the liquid supply unit 20 and upstream of the exhaust flow with respect to the catalyst 10. The third charging unit 331 is, for example, formed or arranged in a tubular shape along the exhaust pipe 3. The third charging unit 331 is positively or negatively charged by applying a voltage.
　制御部５０は、第３帯電部３３１への電圧の印加を制御することにより、第３帯電部３３１に帯電させる電荷の極性、および、帯電させる電荷の量等を制御可能である。すなわち、制御部５０は、第３帯電部３３１の作動を制御可能である。 The control unit 50 can control the polarity of the electric charge charged in the third charging unit 331, the amount of the charged electric charge, and the like by controlling the application of the voltage to the third charging unit 331. That is, the control unit 50 can control the operation of the third charging unit 331.
　図１に示すように、例えば、噴霧形成時に尿素水に帯電させた電荷の極性が正であり、噴射期間終了後に第３帯電部３３１に帯電させた電荷の極性も正の場合、尿素水の噴霧と第３帯電部３３１との間には斥力が生じ、尿素水の噴霧は、第３帯電部３３１および排気管３の径方向内側に移動する。これにより、尿素水の排気管３の内壁への付着を抑制できる。 As shown in FIG. 1, for example, when the polarity of the electric charge charged in the urea water during spray formation is positive and the polarity of the electric charge charged in the third charging unit 331 after the injection period is also positive, A repulsive force is generated between the spray and the third charging unit 331, and the spray of urea water moves radially inward of the third charging unit 331 and the exhaust pipe 3. This can prevent urea water from adhering to the inner wall of the exhaust pipe 3.
　このように、制御部５０は、第３帯電部３３１を帯電させることで、排気管３における尿素水の噴霧の位置を制御可能である。ここで、制御部５０は、噴霧形成時に尿素水に帯電させた電荷と同じ極性の電荷を第３帯電部３３１に帯電させることで、尿素水の排気管３の内壁へ付着することで生じる、噴霧の偏り、および、デポジット形成を抑制できる。 In this way, the control unit 50 can control the position of the spray of urea water in the exhaust pipe 3 by charging the third charging unit 331. Here, the control unit 50 charges the third charging unit 331 with a charge having the same polarity as the charge charged in the urea water at the time of forming the spray, thereby causing the urea water to adhere to the inner wall of the exhaust pipe 3. Uneven spraying and deposit formation can be suppressed.
　次に、本実施形態の制御部５０による液体供給部２０、第１帯電部３１１、第３帯電部３３１の制御に関する処理について、図７に基づき説明する。図７に示す一連の処理Ｓ２００は、例えば車両のイグニッションキーがオンされ制御部５０が起動すると実行される。 Next, processing relating to control of the liquid supply unit 20, the first charging unit 311, and the third charging unit 331 by the control unit 50 of the present embodiment will be described based on FIG. 7. A series of processing S200 shown in FIG. 7 is executed, for example, when the ignition key of the vehicle is turned on and the control unit 50 is activated.
　Ｓ２０１では、制御部５０は、帯電させた尿素水を液体供給部２０から噴射供給する。具体的には、Ｓ１００の処理と同様のため、説明を省略する。Ｓ２０１の後、処理はＳ２０２へ移行する。 In S201, the control unit 50 jets and supplies the charged urea water from the liquid supply unit 20. Specifically, since it is the same as the process of S100, the description thereof will be omitted. After S201, the process proceeds to S202.
　Ｓ２０２では、制御部５０は、排気の流速から、第３帯電部３３１に電圧を印加する期間である印加期間を算出する。具体的には、制御部５０は、排気の流速に基づき、尿素水の噴霧が第３帯電部３３１を通過する時間を推定し、推定した時間に基づき、印加期間を算出する。Ｓ２０２の後、処理はＳ２０３へ移行する。 In S202, the control unit 50 calculates an application period, which is a period in which the voltage is applied to the third charging unit 331, from the flow velocity of exhaust gas. Specifically, the control unit 50 estimates the time for the urea water spray to pass through the third charging unit 331 based on the flow velocity of the exhaust gas, and calculates the application period based on the estimated time. After S202, the process proceeds to S203.
　Ｓ２０３では、制御部５０は、第３帯電部３３１に電圧を印加する。これにより、第３帯電部３３１を通過する尿素水の噴霧が排気管３の内壁に付着するのを抑制できる。Ｓ２０３の後、処理はＳ２０４へ移行する。 In S203, the control unit 50 applies a voltage to the third charging unit 331. Accordingly, it is possible to suppress the spray of urea water passing through the third charging unit 331 from adhering to the inner wall of the exhaust pipe 3. After S203, the process proceeds to S204.
　Ｓ２０４では、制御部５０は、Ｓ２０２で算出した印加期間の終了後、第３帯電部３３１への電圧の印加を停止する。Ｓ２０４の後、制御部５０は、一連の処理Ｓ２００を終了する。 In S204, the control unit 50 stops applying the voltage to the third charging unit 331 after the application period calculated in S202 ends. After S204, the control unit 50 ends the series of processes S200.
　制御部５０は、Ｓ２０４の後、一連の処理Ｓ２００を終了し、その後、再び処理Ｓ２００を開始する。このように、処理Ｓ２００は、制御部５０の起動中、繰り返し実行される処理である。 After S204, the control unit 50 ends the series of processes S200, and then starts the process S200 again. In this way, the process S200 is a process that is repeatedly executed during the activation of the control unit 50.
　以上説明したように、本実施形態は、エンジン２の排気中に液体としての尿素水を供給する液体供給システム１であって、液体供給部２０と第１帯電部３１１と制御部５０とを備えている。液体供給部２０は、エンジン２の排気中に尿素水を噴射供給する。第１帯電部３１１は、電圧の印加により帯電し、液体供給部２０から噴射される尿素水を帯電させることが可能である。制御部５０は、液体供給部２０および第１帯電部３１１の作動を制御する。制御部５０は、液体供給部２０および第１帯電部３１１の作動を制御し、帯電した状態の尿素水を排気中に供給することが可能である。 As described above, the present embodiment is the liquid supply system 1 that supplies the urea water as a liquid into the exhaust gas of the engine 2, and includes the liquid supply unit 20, the first charging unit 311, and the control unit 50. ing. The liquid supply unit 20 injects and supplies urea water into the exhaust gas of the engine 2. The first charging unit 311 can be charged by applying a voltage and can charge the urea water ejected from the liquid supply unit 20. The control unit 50 controls the operations of the liquid supply unit 20 and the first charging unit 311. The control unit 50 can control the operations of the liquid supply unit 20 and the first charging unit 311 to supply the charged urea water into the exhaust gas.
　本実施形態では、帯電した状態の尿素水は、静電力による***、すなわち、クーロン***により微粒化する。そのため、排気中に供給する尿素水の噴霧を微粒化でき、さらにその電荷により拡散する。このように、本実施形態は、噴射する尿素水を微粒化および均質化可能である。これにより、還元剤としての尿素水を排気中に噴射供給した場合、下流の触媒１０による排気の浄化を効果的に促進することができる。 In the present embodiment, the urea water in a charged state is atomized by the division by electrostatic force, that is, Coulomb division. Therefore, the spray of urea water supplied into the exhaust gas can be atomized and further diffused by the charge. As described above, this embodiment can atomize and homogenize the injected urea water. As a result, when urea water as a reducing agent is injected and supplied into the exhaust gas, purification of the exhaust gas by the downstream catalyst 10 can be effectively promoted.
　また、本実施形態では、第１帯電部３１１は、液体供給部２０と一体に設けられている。液体供給システム１は、尿素水の噴霧形成時に尿素水を帯電させる。そのため、噴霧形成時の微粒化促進、クーロン力による噴霧の拡散等の静電噴霧の効果時間を最大限に確保できる。 In addition, in the present embodiment, the first charging unit 311 is provided integrally with the liquid supply unit 20. The liquid supply system 1 charges the urea water when forming the spray of the urea water. Therefore, it is possible to maximize the effect time of the electrostatic spray such as promotion of atomization during spray formation and diffusion of spray due to Coulomb force.
　また、本実施形態は、第２帯電部３２１をさらに備えている。第２帯電部３２１は、液体供給部２０に設けられ、電圧の印加により帯電する。制御部５０は、第１帯電部３１１または第２帯電部３２１を帯電させることで、尿素水の噴霧の位置を制御可能である。そのため、液体供給部２０に設けた第１帯電部３１１または第２帯電部３２１のみで、尿素水の噴霧の位置を制御可能である。 Moreover, the present embodiment further includes a second charging unit 321. The second charging unit 321 is provided in the liquid supply unit 20 and is charged by applying a voltage. The control unit 50 can control the spray position of the urea water by charging the first charging unit 311 or the second charging unit 321. Therefore, the spray position of the urea water can be controlled only by the first charging unit 311 or the second charging unit 321 provided in the liquid supply unit 20.
　また、制御部５０は、液体供給部２０からの尿素水の噴射期間終了後の所定期間、第１帯電部３１１または第２帯電部３２１を帯電させることで、尿素水の噴霧の位置を制御可能である。そのため、噴射後の噴孔２２内に残留した尿素水を押し出し、後ダレを抑制できる。 Further, the control unit 50 can control the position of spraying the urea water by charging the first charging unit 311 or the second charging unit 321 for a predetermined period after the end of the injection period of the urea water from the liquid supply unit 20. Is. Therefore, the urea water remaining in the injection hole 22 after the injection can be pushed out, and the post sag can be suppressed.
　また、制御部５０は、排気の流速が高い程、噴射期間終了後に第１帯電部３１１または第２帯電部３２１に帯電させる電荷の量を大きくする。そのため、排気流に対し噴霧を拡散させるための貫徹力を十分に確保できる。 Further, the control unit 50 increases the amount of electric charge charged in the first charging unit 311 or the second charging unit 321 after the injection period ends, as the flow velocity of the exhaust gas is higher. Therefore, sufficient penetration force for diffusing the spray with respect to the exhaust flow can be secured.
　また、本実施形態では、制御部５０は、液体供給部２０からの尿素水の噴射期間中、排気の流速に応じた電圧を第１帯電部３１１または第２帯電部３２１に印加する。そのため、排気流に対し噴霧を拡散させるための貫徹力を確保できる。 Further, in the present embodiment, the control unit 50 applies the voltage according to the flow rate of the exhaust gas to the first charging unit 311 or the second charging unit 321 during the injection period of the urea water from the liquid supply unit 20. Therefore, the penetration force for diffusing the spray with respect to the exhaust flow can be secured.
　また、本実施形態では、制御部５０は、排気の流速が高い程、第１帯電部３１１または第２帯電部３２１に印加する電圧の印加量を大きくする。そのため、排気流に対し噴霧を拡散させるための貫徹力を十分に確保できる。 Further, in the present embodiment, the control unit 50 increases the application amount of the voltage applied to the first charging unit 311 or the second charging unit 321 as the flow velocity of the exhaust gas is higher. Therefore, sufficient penetration force for diffusing the spray with respect to the exhaust flow can be secured.
　また、本実施形態では、制御部５０は、液体供給部２０からの尿素水の噴射期間中、排気の温度に応じた電圧を第１帯電部３１１に印加する。そのため、排気における尿素水の気化の進み易さに応じて尿素水を微粒化できる。 Further, in the present embodiment, the control unit 50 applies the voltage according to the temperature of the exhaust gas to the first charging unit 311 during the injection period of the urea water from the liquid supply unit 20. Therefore, the urea water can be atomized according to the ease of vaporization of the urea water in the exhaust gas.
　また、本実施形態では、制御部５０は、排気の温度が低い程、第１帯電部３１１に印加する電圧の印加量を大きくする。そのため、排気の温度が低く、排気において尿素水の気化が進み難いとき程、尿素水の噴霧を微粒化でき、尿素水の気化を促進できる。 Further, in the present embodiment, the control unit 50 increases the application amount of the voltage applied to the first charging unit 311 as the temperature of the exhaust gas is lower. Therefore, when the temperature of the exhaust gas is low and the vaporization of the urea water is difficult to proceed in the exhaust gas, the spray of the urea water can be atomized, and the vaporization of the urea water can be promoted.
　また、本実施形態では、制御部５０は、液体供給部２０からの尿素水の噴射期間が短い程、噴射開始よりも前に、第１帯電部３１１または第２帯電部３２１への電圧の印加を開始する。そのため、噴霧への帯電の遅れを抑制し、静電効果を確保できる。 In addition, in the present embodiment, the control unit 50 applies the voltage to the first charging unit 311 or the second charging unit 321 before the start of injection, as the injection period of the urea water from the liquid supply unit 20 is shorter. To start. Therefore, it is possible to suppress the delay of charging to the spray and secure the electrostatic effect.
　また、本実施形態では、制御部５０は、液体供給部２０からの尿素水の噴射の頻度が所定値以上となる期間中、第１帯電部３１１または第２帯電部３２１への電圧の印加を継続する。そのため、噴霧への帯電の遅れを効果的に抑制し、静電効果を確保できる。 Further, in the present embodiment, the control unit 50 applies the voltage to the first charging unit 311 or the second charging unit 321 during the period when the frequency of the injection of the urea water from the liquid supply unit 20 is equal to or higher than the predetermined value. continue. Therefore, the delay of charging to the spray can be effectively suppressed and the electrostatic effect can be secured.
　また、本実施形態は、第３帯電部３３１をさらに備えている。第３帯電部３３１は、排気が流れる排気管３に設けられ、電圧の印加により帯電する。制御部５０は、第３帯電部３３１を帯電させることで、排気管３における尿素水の噴霧の位置を制御可能である。そのため、尿素水の噴霧の排気管３の内壁への付着を抑制し、噴霧の均一化、および、デポジットの抑制を図ることができる。また、排気中における噴霧の濃淡を抑制できる。 The present embodiment further includes a third charging unit 331. The third charging unit 331 is provided in the exhaust pipe 3 through which exhaust flows and is charged by applying a voltage. The control unit 50 can control the position of the spray of urea water in the exhaust pipe 3 by charging the third charging unit 331. Therefore, it is possible to prevent the spray of the urea water from adhering to the inner wall of the exhaust pipe 3, and to make the spray uniform and suppress the deposit. Further, it is possible to suppress the density of the spray during the exhaust.
　また、本実施形態では、第３帯電部３３１は、液体供給部２０の下流に設けられる。制御部５０は、噴霧形成時に尿素水に帯電させた電荷と同じ極性の電荷を第３帯電部３３１に帯電させる。そのため、尿素水の噴霧の排気管３の内壁への付着を抑制できる。 Further, in the present embodiment, the third charging unit 331 is provided downstream of the liquid supply unit 20. The control unit 50 charges the third charging unit 331 with a charge having the same polarity as the charge charged in the urea water during spray formation. Therefore, it is possible to prevent the spray of urea water from adhering to the inner wall of the exhaust pipe 3.
　また、本実施形態では、制御部５０は、液体供給部２０からの尿素水の噴射開始後の所定期間である印加期間のみ、第３帯電部３３１に電圧を印加する。そのため、第３帯電部３３１の消費電力を抑制できる。 Further, in the present embodiment, the control unit 50 applies the voltage to the third charging unit 331 only during the application period which is a predetermined period after the injection of the urea water from the liquid supply unit 20 is started. Therefore, the power consumption of the third charging unit 331 can be suppressed.
　また、本実施形態では、制御部５０は、排気の流速に基づき、尿素水の噴霧が第３帯電部３３１を通過する時間を推定し、推定した時間に基づき、前記印加期間を算出する。そのため、排気の条件に応じて前記印加時間を設定でき、第３帯電部３３１の消費電力をより適切に抑制できる。 Further, in the present embodiment, the control unit 50 estimates the time for the urea water spray to pass through the third charging unit 331 based on the flow velocity of the exhaust gas, and calculates the application period based on the estimated time. Therefore, the application time can be set according to the exhaust condition, and the power consumption of the third charging unit 331 can be suppressed more appropriately.
　　（第２実施形態）
　第２実施形態による液体供給システムの一部を図８に示す。第２実施形態は、排気管３、第３帯電部３３１の構成等が第１実施形態と異なる。 (Second embodiment)
FIG. 8 shows a part of the liquid supply system according to the second embodiment. The second embodiment differs from the first embodiment in the configuration of the exhaust pipe 3, the third charging unit 331, and the like.
　本実施形態では、排気管３は、排気流れの上流側から下流側に向かって曲がる曲がり部４を有している。曲がり部４は、第３帯電部３３１に対し排気流れの上流側に形成されている。液体供給部２０は、曲がり部４に対し排気流れの上流側に設けられる。 In the present embodiment, the exhaust pipe 3 has a bent portion 4 that bends from the upstream side to the downstream side of the exhaust flow. The bent portion 4 is formed on the upstream side of the exhaust flow with respect to the third charging portion 331. The liquid supply part 20 is provided upstream of the exhaust flow with respect to the bending part 4.
　本実施形態では、第３帯電部３３２をさらに備えている。第３帯電部３３２は、曲がり部４に設けられる。第３帯電部３３２は、内側帯電部３３３、外側帯電部３３４を有している。内側帯電部３３３は、排気管３の曲がり部４の曲げ半径の内側に設けられる。外側帯電部３３４は、排気管３の曲がり部４の曲げ半径の外側に設けられる。 In the present embodiment, the third charging unit 332 is further provided. The third charging section 332 is provided on the bending section 4. The third charging section 332 has an inner charging section 333 and an outer charging section 334. The inner charging portion 333 is provided inside the bending radius of the bent portion 4 of the exhaust pipe 3. The outer charging portion 334 is provided outside the bending radius of the bent portion 4 of the exhaust pipe 3.
　制御部５０は、第３帯電部３３２の内側帯電部３３３、外側帯電部３３４への電圧の印加を制御することにより、内側帯電部３３３、外側帯電部３３４に帯電させる電荷の極性、および、帯電させる電荷の量等を制御可能である。すなわち、制御部５０は、内側帯電部３３３、外側帯電部３３４の作動を制御可能である。 The control unit 50 controls the voltage application to the inner charging unit 333 and the outer charging unit 334 of the third charging unit 332 to control the polarity of the charge to be charged to the inner charging unit 333 and the outer charging unit 334, and the charging It is possible to control the amount of electric charges to be generated. That is, the control unit 50 can control the operations of the inner charging unit 333 and the outer charging unit 334.
　制御部５０は、例えば、噴霧形成時に尿素水に帯電させた電荷である正の電荷とは逆の極性の電荷である負の電荷を内側帯電部３３３に帯電させ、噴霧形成時に尿素水に帯電させた電荷と同じ極性の電荷である正の電荷を外側帯電部３３４に帯電させる（図８参照）。そのため、液体供給部２０から噴射された後、曲がり部４を通過する尿素水の噴霧には、外側帯電部３３４からは反力が作用し、内側帯電部３３３からは引力が作用する。これにより、噴霧は、曲がり部４において遠心力を受けつつも排気管３の中心付近を通過する。 For example, the control unit 50 charges the inner charging unit 333 with a negative charge having a polarity opposite to the positive charge that is the charge charged in the urea water during spray formation, and charges the urea water during the spray formation. The outer charging section 334 is charged with positive charges having the same polarity as the applied charges (see FIG. 8). Therefore, a reaction force acts from the outer charging portion 334, and an attractive force acts from the inner charging portion 333, to the spray of urea water that has passed through the bending portion 4 after being ejected from the liquid supply portion 20. As a result, the spray passes near the center of the exhaust pipe 3 while being subjected to the centrifugal force in the bent portion 4.
　また、制御部５０は、排気の流速が高くなるに従い、内側帯電部３３３および外側帯電部３３４に印加する電圧の印加量を増大させる。 Further, the control unit 50 increases the applied amount of the voltage applied to the inner charging unit 333 and the outer charging unit 334 as the flow velocity of the exhaust gas increases.
　以上説明したように、本実施形態では、第３帯電部３３２は、排気管３の曲がり部４の曲げ半径の内側に設けられた内側帯電部３３３、および、曲がり部４の曲げ半径の外側に設けられた外側帯電部３３４を有している。制御部５０は、噴霧形成時に尿素水に帯電させた電荷とは逆の極性の電荷を内側帯電部３３３に帯電させ、噴霧形成時に尿素水に帯電させた電荷と同じ極性の電荷を外側帯電部３３４に帯電させる。そのため、液体供給部２０から噴射された後、曲がり部４を通過する尿素水の噴霧には、外側帯電部３３４からは反力が作用し、内側帯電部３３３からは引力が作用する。これにより、噴霧は、曲がり部４において遠心力を受けつつも排気管３の中心付近を通過する。その結果、噴霧が排気管３の曲がり部４の内壁に付着するのを抑制できる。 As described above, in the present embodiment, the third charging portion 332 is provided inside the bending radius of the bent portion 4 of the exhaust pipe 3 and inside the bending radius of the bending portion 4 outside the bending radius of the bending portion 4. It has an outer charging section 334 provided. The control unit 50 charges the inner charging unit 333 with a charge having a polarity opposite to the charge charged in the urea water during spray formation, and charges the outer charging unit with a charge having the same polarity as the charge charged in the urea water during spray formation. 334 is charged. Therefore, a reaction force acts from the outer charging portion 334, and an attractive force acts from the inner charging portion 333, to the spray of urea water that has passed through the bending portion 4 after being ejected from the liquid supply portion 20. As a result, the spray passes near the center of the exhaust pipe 3 while being subjected to the centrifugal force in the bent portion 4. As a result, it is possible to prevent the spray from adhering to the inner wall of the bent portion 4 of the exhaust pipe 3.
　また、本実施形態では、制御部５０は、排気の流速が高くなるに従い、内側帯電部３３３および外側帯電部３３４に印加する電圧の印加量を増大させる。そのため、曲がり部４において排気の流れの剥離等により噴霧が偏るのを効果的に抑制できる。 Further, in the present embodiment, the control unit 50 increases the application amount of the voltage applied to the inner charging unit 333 and the outer charging unit 334 as the flow velocity of exhaust gas increases. Therefore, it is possible to effectively suppress uneven spraying at the bent portion 4 due to separation of the flow of exhaust gas or the like.
　　（第３実施形態）
　第３実施形態による液体供給システムについて図９、１０に基づき説明する。第３実施形態は、排気管３の構成等が第１実施形態と異なる。 (Third Embodiment)
A liquid supply system according to the third embodiment will be described with reference to FIGS. The third embodiment is different from the first embodiment in the configuration of the exhaust pipe 3 and the like.
　本実施形態では、排気管３は、排気流れの上流側から下流側に向かって曲がる曲がり部４を有している。液体供給部２０は、曲がり部４に対し排気流れの上流側に設けられる（図１０参照）。具体的には、液体供給部２０は、曲がり部４の曲がり半径の内側の部分に対し上流側に設けられ、曲がり部４の曲がり半径の内側から外側へ向かう方向に沿って尿素水を噴射可能である。 In the present embodiment, the exhaust pipe 3 has a bent portion 4 that bends from the upstream side to the downstream side of the exhaust flow. The liquid supply part 20 is provided on the upstream side of the exhaust flow with respect to the bending part 4 (see FIG. 10). Specifically, the liquid supply unit 20 is provided on the upstream side with respect to the portion inside the bending radius of the bending portion 4, and can inject urea water along the direction from the inside of the bending radius of the bending portion 4 to the outside. Is.
　図９に示すように、制御部５０は、例えば、噴射パルスの始期（ｔ１）と終期（ｔ２）との間の期間である尿素水の噴射期間（ｔ１～ｔ２）、第１帯電部３１１または第２帯電部３２１に正の電圧を印加する。これにより、噴射される尿素の噴霧には、正の電荷が帯電する。そして、制御部５０は、液体供給部２０からの尿素水の噴射期間（ｔ１～ｔ２）終了後の所定期間（ｔ２～ｔ３）、第１帯電部３１１または第２帯電部３２１に負の電圧を印加する。なお、このときの電圧の絶対値は、噴射期間（ｔ１～ｔ２）に第１帯電部３１１または第２帯電部３２１に印加した電圧の絶対値よりも高い。 As shown in FIG. 9, the control unit 50 may, for example, a urea water injection period (t1 to t2) that is a period between the start (t1) and end (t2) of the injection pulse, the first charging unit 311 or A positive voltage is applied to the second charging section 321. As a result, the injected urea spray is charged with a positive charge. Then, the control unit 50 applies a negative voltage to the first charging unit 311 or the second charging unit 321 for a predetermined period (t2 to t3) after the end of the injection period (t1 to t2) of the urea water from the liquid supply unit 20. Apply. The absolute value of the voltage at this time is higher than the absolute value of the voltage applied to the first charging unit 311 or the second charging unit 321 during the ejection period (t1 to t2).
　尿素水の噴射後に第１帯電部３１１または第２帯電部３２１に負の電圧を印加することで、第１帯電部３１１または第２帯電部３２１に負の電荷が帯電し、正の電荷が帯電した噴霧と第１帯電部３１１または第２帯電部３２１との間に引力が生じる。これにより、尿素水の噴霧は、第１帯電部３１１または第２帯電部３２１に近付く方向に移動する（図１０参照）。これにより、噴霧は、曲がり部４において遠心力を受けつつも排気管３の中心付近を通過する。その結果、噴霧が排気管３の曲がり部４の内壁に付着するのを抑制できる。 By applying a negative voltage to the first charging unit 311 or the second charging unit 321 after the injection of the urea water, the first charging unit 311 or the second charging unit 321 is charged with a negative charge and the positive charge is charged. An attractive force is generated between the spray and the first charging unit 311 or the second charging unit 321. As a result, the spray of urea water moves in a direction approaching the first charging unit 311 or the second charging unit 321 (see FIG. 10). As a result, the spray passes near the center of the exhaust pipe 3 while being subjected to the centrifugal force in the bent portion 4. As a result, it is possible to prevent the spray from adhering to the inner wall of the bent portion 4 of the exhaust pipe 3.
　以上説明したように、本実施形態では、制御部５０は、噴射期間終了後、噴霧形成時に尿素水に帯電させた電荷とは逆の極性の電荷を第１帯電部３１１または第２帯電部３２１に帯電させる。これにより、噴射後の遠心力等の影響を見越し、噴霧を液体供給部２０の近傍に留めることができる。 As described above, in the present embodiment, after the injection period ends, the control unit 50 causes the first charging unit 311 or the second charging unit 321 to apply a charge having a polarity opposite to the charge charged in the urea water at the time of spray formation. To charge. As a result, the spray can be kept in the vicinity of the liquid supply unit 20 in anticipation of the influence of the centrifugal force and the like after the injection.
　　（第４実施形態）
　第４実施形態による液体供給システムの一部を図１１に示す。第４実施形態は、「下帯電部」としての第４帯電部３４１をさらに備える点等で第１実施形態と異なる。 (Fourth Embodiment)
FIG. 11 shows a part of the liquid supply system according to the fourth embodiment. The fourth embodiment differs from the first embodiment in that it further includes a fourth charging section 341 as a “lower charging section”.
　本実施形態は、第４帯電部３４１、検出部７０をさらに備える。図１１に示すように、第４帯電部３４１は、排気管３に設けられる。具体的には、第４帯電部３４１は、第３帯電部３３１に対し排気流れの下流側であって、触媒１０に対し排気流れの上流側に設けられる。第４帯電部３４１は、例えば、円形の網状に形成されている。第４帯電部３４１は、電圧の印加により正または負に帯電する。 The present embodiment further includes a fourth charging unit 341 and a detection unit 70. As shown in FIG. 11, the fourth charging unit 341 is provided in the exhaust pipe 3. Specifically, the fourth charging unit 341 is provided on the downstream side of the exhaust flow with respect to the third charging unit 331 and on the upstream side of the exhaust flow with respect to the catalyst 10. The fourth charging unit 341 is formed, for example, in a circular net shape. The fourth charging unit 341 is positively or negatively charged by applying a voltage.
　制御部５０は、第４帯電部３４１への電圧の印加を制御することにより、第４帯電部３４１に帯電させる電荷の極性、および、帯電させる電荷の量等を制御可能である。すなわち、制御部５０は、第４帯電部３４１の作動を制御可能である。 The control unit 50 can control the polarity of the electric charge charged in the fourth charging unit 341, the amount of the charged electric charge, and the like by controlling the voltage application to the fourth charging unit 341. That is, the control unit 50 can control the operation of the fourth charging unit 341.
　制御部５０は、尿素水の噴霧が第４帯電部３４１を通過するよりも前に、噴霧形成時に尿素水に帯電させた電荷と同じ極性の電荷を第４帯電部３４１に帯電させる。そのため、尿素水の噴霧は、第４帯電部３４１を通過するよりも前に、第４帯電部３４１からの反発力により速度が低下する。これにより、触媒１０の上流側または触媒１０において尿素水が気化する時間を確保できる。 The control unit 50 charges the fourth charging unit 341 with an electric charge having the same polarity as the electric charge charged in the urea water during spray formation, before the spray of urea water passes through the fourth charging unit 341. Therefore, the speed of spraying the urea water decreases due to the repulsive force from the fourth charging unit 341 before passing through the fourth charging unit 341. As a result, it is possible to secure the time for the urea water to vaporize on the upstream side of the catalyst 10 or in the catalyst 10.
　検出部７０は、触媒１０の内部に複数設けられる。検出部７０は、例えば、触媒１０の径方向および周方向に均等に配置される。検出部７０は、例えば温度センサであって、触媒１０の内部において周囲の温度を検出可能である。検出部７０は、検出した温度に対応する信号を制御部５０に送信する。 A plurality of detection units 70 are provided inside the catalyst 10. The detection units 70 are evenly arranged in the radial direction and the circumferential direction of the catalyst 10, for example. The detection unit 70 is, for example, a temperature sensor and can detect the ambient temperature inside the catalyst 10. The detection unit 70 transmits a signal corresponding to the detected temperature to the control unit 50.
　制御部５０は、複数の検出部７０からの信号に基づき、触媒１０における反応物質である尿素またはアンモニアの分布を推定可能である。制御部５０は、推定した反応物質の分布に基づき、第３帯電部３３１に電圧を印加する。これにより、第３帯電部３３１を通過する噴霧の位置を制御し、触媒１０における反応物質の分布の偏りを抑制可能である。 The control unit 50 can estimate the distribution of the reactant urea or ammonia in the catalyst 10 based on the signals from the plurality of detection units 70. The controller 50 applies a voltage to the third charging unit 331 based on the estimated distribution of the reactant. This makes it possible to control the position of the spray passing through the third charging unit 331 and suppress the uneven distribution of the reactant in the catalyst 10.
　次に、本実施形態の制御部５０による、触媒１０における反応物質の分布の推定、および、第３帯電部３３１の制御に関する処理について、図１２、１３に基づき説明する。図１２に示す一連の処理Ｓ３００は、例えば車両のイグニッションキーがオンされ制御部５０が起動すると実行される。 Next, the processing relating to the estimation of the distribution of the reactants in the catalyst 10 and the control of the third charging unit 331 by the control unit 50 of the present embodiment will be described based on FIGS. A series of processing S300 shown in FIG. 12 is executed, for example, when the ignition key of the vehicle is turned on and the control unit 50 is activated.
　Ｓ３０１では、制御部５０は、触媒１０における反応物質の分布を推定する。具体的には、制御部５０は、図１３に示す一連の処理Ｓ４００を実行することにより、触媒１０における反応物質の分布を推定する。 In S301, the control unit 50 estimates the distribution of the reactants in the catalyst 10. Specifically, the control unit 50 estimates the distribution of the reactant in the catalyst 10 by executing the series of processing S400 shown in FIG.
　Ｓ４０１では、制御部５０は、現在の触媒１０の温度分布を取得する。具体的には、触媒１０内部に設けた複数の検出部７０からの信号に基づき、現在の触媒１０の温度分布を取得する。Ｓ４０１の後、処理はＳ４０２へ移行する。 In S401, the control unit 50 acquires the current temperature distribution of the catalyst 10. Specifically, the current temperature distribution of the catalyst 10 is acquired based on the signals from the plurality of detection units 70 provided inside the catalyst 10. After S401, the process proceeds to S402.
　Ｓ４０２では、制御部５０は、排気と触媒１０との温度差ΔＴに基づき、触媒１０における反応物質の分布を推定する。 In S402, the control unit 50 estimates the distribution of the reactants in the catalyst 10 based on the temperature difference ΔT between the exhaust gas and the catalyst 10.
　触媒１０において反応物質が反応するとき、反応熱が生じる。よって、図１４に示すように、排気と触媒１０との温度差ΔＴが大きい程、触媒１０上の反応物質である尿素またはアンモニアの量は多いと考えられる。そのため、制御部５０は、Ｓ４０１で取得した触媒１０の温度分布に基づき、排気との温度差ΔＴが大きい位置程、反応物質の量が多いと推定し、触媒１０の径方向における反応物質の分布を推定する（図１５参照）。図１５に示すように、触媒１０上の数字が大きい位置程、反応物質の量が多いと推定する。制御部５０は、Ｓ４０２の後、Ｓ４００を終了し、Ｓ３０２に移行する。 When the reactants react in the catalyst 10, heat of reaction is generated. Therefore, as shown in FIG. 14, it is considered that the larger the temperature difference ΔT between the exhaust gas and the catalyst 10, the larger the amount of urea or ammonia that is a reactant on the catalyst 10. Therefore, based on the temperature distribution of the catalyst 10 acquired in S401, the control unit 50 estimates that the larger the temperature difference ΔT with the exhaust gas is, the larger the amount of the reactant is, and the distribution of the reactant in the radial direction of the catalyst 10. Is estimated (see FIG. 15). As shown in FIG. 15, it is estimated that the larger the number on the catalyst 10, the larger the amount of the reactant. After S402, the control unit 50 ends S400 and proceeds to S302.
　Ｓ３０２では、制御部５０は、推定した触媒１０における反応物質の分布に基づき、触媒１０において静電力をかける方向、大きさを決定する。Ｓ３０２の後、処理はＳ３０２へ移行する。 In S302, the control unit 50 determines the direction and size of the electrostatic force to be applied to the catalyst 10 based on the estimated distribution of the reactants in the catalyst 10. After S302, the process proceeds to S302.
　Ｓ３０３では、制御部５０は、Ｓ３０２で決定した、触媒１０において静電力をかける方向、大きさに基づき、第３帯電部３３１に電圧を印加する。具体的には、第３帯電部３３１のうち、反応物質の量が多い側に正の電荷を帯電させ、反応物質の量が少ない側に負の電荷を帯電させる。これにより、正の電荷が帯電した尿素水の噴霧は、触媒１０における反応物質の分布の少ない方向へ移動する。これにより、第３帯電部３３１を通過する噴霧の位置を制御し、触媒１０における反応物質の分布の偏りを抑制可能である。 In S303, the control unit 50 applies a voltage to the third charging unit 331 based on the direction and magnitude of the electrostatic force applied to the catalyst 10 determined in S302. Specifically, in the third charging unit 331, the side having a large amount of the reaction substance is charged with a positive charge, and the side having a small amount of the reaction substance is charged with a negative charge. As a result, the spray of urea water having a positive charge moves in the direction in which the distribution of the reactants in the catalyst 10 is small. This makes it possible to control the position of the spray passing through the third charging unit 331 and suppress the uneven distribution of the reactant in the catalyst 10.
　なお、このとき、制御部５０は、図１６に示すように、排気との温度差が大きい程、すなわち、推定した分布の偏りが大きい程、第３帯電部３３１への電圧の印加量を大きくする。Ｓ３０３の後、制御部５０は、一連の処理Ｓ３００を終了する。 At this time, as shown in FIG. 16, the control unit 50 increases the amount of voltage applied to the third charging unit 331 as the temperature difference from the exhaust gas is larger, that is, the estimated distribution bias is larger. To do. After S303, the control unit 50 ends the series of processes S300.
　制御部５０は、Ｓ３０３の後、一連の処理Ｓ３００を終了し、その後、再び処理Ｓ３００を開始する。このように、処理Ｓ３００は、制御部５０の起動中、繰り返し実行される処理である。 The control unit 50 ends the series of processes S300 after S303, and then starts the process S300 again. As described above, the process S300 is a process that is repeatedly executed during the activation of the control unit 50.
　以上説明したように、本実施形態では、液体供給部２０から噴射される液体は、液体供給部２０の下流に設けられた触媒１０上で反応する反応物質である尿素またはアンモニアを含む液体である。制御部５０は、触媒１０の径方向の反応物質の分布を推定し、推定した分布に基づき、反応物質の分布の少ない方向へ尿素水の噴霧が移動するよう、第３帯電部３３１への電圧の印加を制御する。これにより、触媒１０における反応物質の分布を均一化し、触媒１０の利用率を向上させることができる。 As described above, in the present embodiment, the liquid ejected from the liquid supply unit 20 is a liquid containing urea or ammonia that is a reaction substance that reacts on the catalyst 10 provided downstream of the liquid supply unit 20. .. The control unit 50 estimates the distribution of the reactant in the radial direction of the catalyst 10, and based on the estimated distribution, the voltage to the third charging unit 331 is adjusted so that the urea water spray moves in the direction in which the distribution of the reactant is small. Control the application of. Thereby, the distribution of the reactants in the catalyst 10 can be made uniform, and the utilization rate of the catalyst 10 can be improved.
　また、本実施形態では、制御部５０は、触媒１０の内部に設けられ周囲の温度を検出可能な複数の検出部７０により検出した温度に基づき、触媒１０の径方向の反応物質の分布を推定する。このように、本実施形態では、触媒１０における反応物質の反応熱に基づき、触媒１０の径方向の反応物質の分布を推定する。 Further, in the present embodiment, the control unit 50 estimates the distribution of the reactant in the radial direction of the catalyst 10 based on the temperatures detected by the plurality of detection units 70 provided inside the catalyst 10 and capable of detecting the ambient temperature. To do. As described above, in the present embodiment, the distribution of the reactant in the radial direction of the catalyst 10 is estimated based on the reaction heat of the reactant in the catalyst 10.
　また、本実施形態では、制御部５０は、触媒１０の径方向の反応物質の分布を推定し、推定した分布の偏りが大きい程、第３帯電部３３１への電圧の印加量を大きくする。これにより、触媒１０における反応物質の分布の偏りを速やかに抑制できる。 Further, in the present embodiment, the control unit 50 estimates the distribution of the reactants in the radial direction of the catalyst 10, and increases the amount of voltage applied to the third charging unit 331 as the estimated distribution bias increases. Accordingly, it is possible to quickly suppress the uneven distribution of the reactants in the catalyst 10.
　また、本実施形態は、第４帯電部３４１をさらに備える。第４帯電部３４１は、液体供給部２０の下流に設けられた触媒１０の上流側に設けられ、電圧の印加により帯電する。そのため、噴霧形成時に尿素水に帯電させた電荷と同じ極性の電荷を第４帯電部３４１に帯電させた場合、尿素水の噴霧は、第４帯電部３４１を通過するとき、第４帯電部３４１からの反発力により速度が低下する。これにより、触媒１０の上流側または触媒１０において尿素水が気化する時間を確保できる。 The present embodiment further includes a fourth charging unit 341. The fourth charging unit 341 is provided on the upstream side of the catalyst 10 provided on the downstream side of the liquid supply unit 20, and is charged by applying a voltage. Therefore, when the fourth charging unit 341 is charged with a charge having the same polarity as the charge charged in the urea water during spray formation, the urea water spray causes the fourth charging unit 341 to pass when passing through the fourth charging unit 341. The repulsive force from reduces the speed. As a result, it is possible to secure the time for the urea water to vaporize on the upstream side of the catalyst 10 or in the catalyst 10.
　また、本実施形態では、制御部５０は、尿素水の噴霧が第４帯電部３４１を通過するよりも前に、噴霧形成時に尿素水に帯電させた電荷と同じ極性の電荷を第４帯電部３４１に帯電させる。そのため、尿素水の噴霧は、第４帯電部３４１を通過するよりも前に、第４帯電部３４１からの反発力により速度が低下する。これにより、触媒１０の上流側または触媒１０において尿素水が気化する時間を十分に確保できる。 In addition, in the present embodiment, the control unit 50 causes the fourth charging unit to apply the charge having the same polarity as the charge charged in the urea water at the time of forming the spray, before the spray of the urea water passes through the fourth charging unit 341. 341 is charged. Therefore, the speed of spraying the urea water decreases due to the repulsive force from the fourth charging unit 341 before passing through the fourth charging unit 341. As a result, it is possible to secure a sufficient time for the urea water to vaporize on the upstream side of the catalyst 10 or on the catalyst 10.
　　（他の実施形態）
　上述の第４実施形態では、周囲の温度を検出可能な複数の検出部７０は、触媒１０の内部に設けられる例を示した。これに対し、他の実施形態では、周囲の温度を検出可能な複数の検出部７０は、触媒１０の下流に設けられてもよい。 (Other embodiments)
In the above-described fourth embodiment, the example in which the plurality of detection units 70 capable of detecting the ambient temperature are provided inside the catalyst 10 has been shown. On the other hand, in another embodiment, the plurality of detection units 70 capable of detecting the ambient temperature may be provided downstream of the catalyst 10.
　また、他の実施形態では、触媒１０の内部または触媒１０の下流に設けられる複数の検出部７０は、周囲の窒素酸化物の濃度を検出可能であってもよい。この場合、制御部５０は、複数の検出部７０により検出した窒素酸化物の濃度に基づき、触媒１０の径方向の反応物質の分布を推定してもよい。このように、反応物質により浄化された窒素酸化物の量に基づき、触媒１０の径方向の反応物質の分布を推定してもよい。 Further, in another embodiment, the plurality of detection units 70 provided inside the catalyst 10 or downstream of the catalyst 10 may be able to detect the concentration of the surrounding nitrogen oxides. In this case, the control unit 50 may estimate the distribution of the reactant in the radial direction of the catalyst 10 based on the nitrogen oxide concentrations detected by the plurality of detection units 70. In this way, the distribution of the reactant in the radial direction of the catalyst 10 may be estimated based on the amount of nitrogen oxides purified by the reactant.
　また、他の実施形態では、触媒１０の内部または触媒１０の下流に設けられる複数の検出部７０は、周囲の酸素の濃度を検出可能であってもよい。この場合、制御部５０は、複数の検出部７０により検出した酸素の濃度に基づき、触媒１０の径方向の反応物質の分布を推定してもよい。このように、反応物質と反応した酸素の量に基づき、触媒１０の径方向の反応物質の分布を推定してもよい。 In another embodiment, the plurality of detection units 70 provided inside the catalyst 10 or downstream of the catalyst 10 may be able to detect the concentration of ambient oxygen. In this case, the controller 50 may estimate the distribution of the reactant in the radial direction of the catalyst 10 based on the oxygen concentrations detected by the plurality of detectors 70. In this way, the distribution of the reactant in the radial direction of the catalyst 10 may be estimated based on the amount of oxygen that has reacted with the reactant.
　また、他の実施形態では、触媒１０の内部または触媒１０の下流に設けられる複数の検出部７０は、周囲の反応物質の濃度を検出可能であってもよい。この場合、制御部５０は、複数の検出部７０により検出した反応物質の濃度に基づき、触媒１０の径方向の反応物質の分布を推定してもよい。このように、反応物質の量に基づき、触媒１０の径方向の反応物質の分布を推定してもよい。 Further, in another embodiment, the plurality of detection units 70 provided inside the catalyst 10 or downstream of the catalyst 10 may be capable of detecting the concentrations of the surrounding reactants. In this case, the control unit 50 may estimate the distribution of the reactant in the radial direction of the catalyst 10 based on the concentrations of the reactant detected by the plurality of detectors 70. In this way, the distribution of the reactant in the radial direction of the catalyst 10 may be estimated based on the amount of the reactant.
　また、他の実施形態では、第１帯電部は、液体供給部と別体に設けられていてもよい。また、他の実施形態では、第２帯電部は、液体供給部から離れた位置に設けられていてもよい。 In another embodiment, the first charging section may be provided separately from the liquid supply section. Further, in another embodiment, the second charging section may be provided at a position apart from the liquid supply section.
　また、上述の実施形態では、液体供給部２０から排気中に供給する液体として尿素水を採用し、触媒１０での排気の浄化の促進を図る例を示した。これに対し、他の実施形態では、液体供給部２０から排気中に供給する液体として、例えば炭化水素（ＨＣ）等を採用してもよい。この場合、液体供給部２０の下流に設けたＤＯＣによる昇温やＤＰＦの再生等を図ることができる。 Further, in the above-described embodiment, an example has been shown in which urea water is adopted as the liquid supplied from the liquid supply unit 20 into the exhaust gas to promote purification of the exhaust gas with the catalyst 10. On the other hand, in another embodiment, for example, hydrocarbon (HC) or the like may be adopted as the liquid supplied from the liquid supply unit 20 into the exhaust gas. In this case, it is possible to increase the temperature by the DOC provided downstream of the liquid supply unit 20 and to regenerate the DPF.
　このように、本開示は、上記実施形態に限定されるものではなく、その要旨を逸脱しない範囲で種々の形態で実施可能である。 As described above, the present disclosure is not limited to the above embodiment, and can be implemented in various forms without departing from the gist thereof.
　本開示は、実施形態に基づき記述された。しかしながら、本開示は当該実施形態および構造に限定されるものではない。本開示は、様々な変形例および均等の範囲内の変形をも包含する。また、様々な組み合わせおよび形態、さらには、それらに一要素のみ、それ以上、あるいはそれ以下、を含む他の組み合わせおよび形態も、本開示の範疇および思想範囲に入るものである。 The present disclosure has been described based on the embodiments. However, the present disclosure is not limited to the embodiments and structures. The present disclosure also includes various modifications and modifications within an equivalent range. In addition, various combinations and forms, and other combinations and forms including only one element, more, or less than them are also within the scope and spirit of the present disclosure.

Claims (26)

  1. 　燃焼機関（２）の排気中に液体を供給する液体供給システム（１）であって、
    　前記燃焼機関の排気中に液体を噴射供給する液体供給部（２０）と、
    　電圧の印加により帯電し、前記液体供給部から噴射される液体を帯電させることが可能な帯電部（３１１）と、
    　前記液体供給部および前記帯電部の作動を制御する制御部（５０）と、を備え、
    　前記制御部は、前記液体供給部および前記帯電部の作動を制御し、帯電した状態の液体を排気中に供給することが可能な液体供給システム。     A liquid supply system (1) for supplying liquid into exhaust gas of a combustion engine (2),
    A liquid supply unit (20) for injecting and supplying a liquid into the exhaust gas of the combustion engine;
    A charging unit (311) capable of being charged by applying a voltage and charging the liquid ejected from the liquid supply unit;
    A control unit (50) for controlling the operations of the liquid supply unit and the charging unit,
    The control unit controls the operations of the liquid supply unit and the charging unit, and can supply the charged liquid into the exhaust gas.
  2. 　前記帯電部は、前記液体供給部と一体に設けられ、
    　液体の噴霧形成時に液体を帯電させる請求項１に記載の液体供給システム。     The charging unit is provided integrally with the liquid supply unit,
    The liquid supply system according to claim 1, wherein the liquid is charged when the liquid is sprayed.
  3. 　前記帯電部は、第１帯電部であり、
    　前記液体供給部に設けられ、電圧の印加により帯電する第２帯電部（３２１）をさらに備え、
    　前記制御部は、前記第１帯電部または前記第２帯電部を帯電させることで、液体の噴霧の位置を制御可能である請求項２に記載の液体供給システム。     The charging unit is a first charging unit,
    A second charging unit (321) provided in the liquid supply unit and charged by applying a voltage,
    The liquid supply system according to claim 2, wherein the control unit is capable of controlling the position of liquid spray by charging the first charging unit or the second charging unit.
  4. 　前記制御部は、前記液体供給部からの液体の噴射期間終了後の所定期間、前記第１帯電部または前記第２帯電部を帯電させることで、液体の噴霧の位置を制御可能である請求項３に記載の液体供給システム。 The control unit is capable of controlling the position of liquid spray by charging the first charging unit or the second charging unit for a predetermined period after the end of the liquid ejection period from the liquid supply unit. 3. The liquid supply system according to item 3.
  5. 　前記制御部は、排気の流速が高い程、噴射期間終了後に前記第１帯電部または前記第２帯電部に帯電させる電荷の量を大きくする請求項４に記載の液体供給システム。 The liquid supply system according to claim 4, wherein the control unit increases the amount of electric charges charged in the first charging unit or the second charging unit after the injection period ends, as the flow velocity of the exhaust gas is higher.
  6. 　前記制御部は、噴射期間終了後、噴霧形成時に液体に帯電させた電荷とは逆の極性の電荷を前記第１帯電部または前記第２帯電部に帯電させる請求項４または５に記載の液体供給システム。 The liquid according to claim 4 or 5, wherein the control unit charges the first charging unit or the second charging unit with a charge having a polarity opposite to that of the charge charged in the liquid at the time of forming the spray after the ejection period ends. Supply system.
  7. 　前記制御部は、前記液体供給部からの液体の噴射期間中、排気の流速に応じた電圧を前記第１帯電部または前記第２帯電部に印加する請求項３～６のいずれか一項に記載の液体供給システム。 7. The control unit applies a voltage according to a flow rate of exhaust gas to the first charging unit or the second charging unit during a liquid ejection period from the liquid supply unit. The liquid supply system described.
  8. 　前記制御部は、排気の流速が高い程、前記第１帯電部または前記第２帯電部に印加する電圧の印加量を大きくする請求項７に記載の液体供給システム。 The liquid supply system according to claim 7, wherein the control unit increases the application amount of the voltage applied to the first charging unit or the second charging unit as the flow velocity of exhaust gas is higher.
  9. 　前記制御部は、前記液体供給部からの液体の噴射期間中、排気の温度に応じた電圧を前記第１帯電部に印加する請求項３～８のいずれか一項に記載の液体供給システム。 The liquid supply system according to any one of claims 3 to 8, wherein the control unit applies a voltage according to the temperature of exhaust gas to the first charging unit during a period of ejecting the liquid from the liquid supply unit.
  10. 　前記制御部は、排気の温度が低い程、前記第１帯電部に印加する電圧の印加量を大きくする請求項９に記載の液体供給システム。 The liquid supply system according to claim 9, wherein the control unit increases the amount of voltage applied to the first charging unit as the temperature of the exhaust gas is lower.
  11. 　前記制御部は、前記液体供給部からの液体の噴射期間が短い程、噴射開始よりも前に、前記第１帯電部または前記第２帯電部への電圧の印加を開始する請求項３～１０のいずれか一項に記載の液体供給システム。 11. The control unit starts applying a voltage to the first charging unit or the second charging unit before the start of ejection, as the ejection period of the liquid from the liquid supply unit is shorter. The liquid supply system according to claim 1.
  12. 　前記制御部は、前記液体供給部からの液体の噴射の頻度が所定値以上となる期間中、前記第１帯電部または前記第２帯電部への電圧の印加を継続する請求項３～１１のいずれか一項に記載の液体供給システム。 The control unit continues to apply a voltage to the first charging unit or the second charging unit during a period in which the frequency of ejection of liquid from the liquid supply unit is equal to or higher than a predetermined value. The liquid supply system according to any one of claims.
  13. 　排気が流れる排気管（３）に１つ以上設けられ、電圧の印加により帯電する上帯電部（３３１、３３２）をさらに備え、
    　前記制御部は、前記上帯電部を帯電させることで、前記排気管における液体の噴霧の位置を制御可能である請求項１～１２のいずれか一項に記載の液体供給システム。     One or more exhaust pipes (3) through which exhaust gas flows are further provided with upper charging units (331, 332) that are charged by application of a voltage.
    The liquid supply system according to any one of claims 1 to 12, wherein the control unit is capable of controlling the position of liquid spray in the exhaust pipe by charging the upper charging unit.
  14. 　前記上帯電部は、少なくとも１つが前記液体供給部の下流に設けられ、
    　前記制御部は、噴霧形成時に液体に帯電させた電荷と同じ極性の電荷を前記上帯電部に帯電させる請求項１３に記載の液体供給システム。     At least one of the upper charging section is provided downstream of the liquid supply section,
    The liquid supply system according to claim 13, wherein the control unit charges the upper charging unit with a charge having the same polarity as a charge charged in the liquid during spray formation.
  15. 　前記上帯電部（３３２）は、前記排気管の曲がり部（４）の曲げ半径の内側に設けられた内側帯電部（３３３）、および、前記曲がり部の曲げ半径の外側に設けられた外側帯電部（３３４）を有し、
    　前記制御部は、噴霧形成時に液体に帯電させた電荷とは逆の極性の電荷を前記内側帯電部に帯電させ、噴霧形成時に液体に帯電させた電荷と同じ極性の電荷を前記外側帯電部に帯電させる請求項１３または１４に記載の液体供給システム。     The upper charging part (332) is an inner charging part (333) provided inside a bending radius of the bent part (4) of the exhaust pipe, and an outer charging part provided outside a bending radius of the bent part. A part (334),
    The control unit charges the inner charging unit with a charge having a polarity opposite to the charge charged on the liquid during spray formation, and charges the outer charging unit with a charge having the same polarity as the charge charged on the liquid during spray formation. The liquid supply system according to claim 13 or 14, which is charged.
  16. 　前記制御部は、排気の流速が高くなるに従い、前記内側帯電部および前記外側帯電部に印加する電圧の印加量を増大させる請求項１５に記載の液体供給システム。 The liquid supply system according to claim 15, wherein the control unit increases the amount of voltage applied to the inner charging unit and the outer charging unit as the flow velocity of the exhaust gas increases.
  17. 　前記制御部は、前記液体供給部からの液体の噴射開始後の所定期間である印加期間のみ、前記上帯電部に電圧を印加する請求項１３～１６のいずれか一項に記載の液体供給システム。 The liquid supply system according to any one of claims 13 to 16, wherein the control unit applies the voltage to the upper charging unit only during an application period that is a predetermined period after the liquid ejection from the liquid supply unit is started. ..
  18. 　前記制御部は、排気の流速に基づき、液体の噴霧が前記上帯電部を通過する時間を推定し、推定した時間に基づき、前記印加期間を算出する請求項１７に記載の液体供給システム。 18. The liquid supply system according to claim 17, wherein the control unit estimates the time for the liquid spray to pass through the upper charging unit based on the flow velocity of the exhaust gas, and calculates the application period based on the estimated time.
  19. 　前記液体供給部から噴射される液体は、前記液体供給部の下流に設けられた触媒（１０）上で反応する反応物質を含む液体であり、
    　前記制御部は、前記触媒の径方向の前記反応物質の分布を推定し、推定した分布に基づき、前記反応物質の分布の少ない方向へ液体の噴霧が移動するよう、前記上帯電部への電圧の印加を制御する請求項１３～１８のいずれか一項に記載の液体供給システム。     The liquid ejected from the liquid supply unit is a liquid containing a reactive substance that reacts on the catalyst (10) provided downstream of the liquid supply unit,
    The control unit estimates the distribution of the reactant in the radial direction of the catalyst, and based on the estimated distribution, the voltage to the upper charging unit is adjusted so that the liquid spray moves in the direction in which the distribution of the reactant is small. The liquid supply system according to any one of claims 13 to 18, wherein the application of the liquid is controlled.
  20. 　前記制御部は、前記触媒の内部または前記触媒の下流に設けられ周囲の温度を検出可能な複数の検出部（７０）により検出した温度に基づき、前記触媒の径方向の前記反応物質の分布を推定する請求項１９に記載の液体供給システム。 The controller controls the distribution of the reactant in the radial direction of the catalyst based on the temperature detected by a plurality of detectors (70) provided inside the catalyst or downstream of the catalyst and capable of detecting the ambient temperature. The liquid supply system according to claim 19, which estimates.
  21. 　前記制御部は、前記触媒の内部または前記触媒の下流に設けられ周囲の窒素酸化物の濃度を検出可能な複数の検出部（７０）により検出した濃度に基づき、前記触媒の径方向の前記反応物質の分布を推定する請求項１９または２０に記載の液体供給システム。 The control unit is configured to perform the reaction in the radial direction of the catalyst based on the concentration detected by a plurality of detection units (70) provided inside the catalyst or downstream of the catalyst and capable of detecting the concentration of surrounding nitrogen oxides. The liquid supply system according to claim 19 or 20, which estimates the distribution of substances.
  22. 　前記制御部は、前記触媒の内部または前記触媒の下流に設けられ周囲の酸素の濃度を検出可能な複数の検出部（７０）により検出した濃度に基づき、前記触媒の径方向の前記反応物質の分布を推定する請求項１９～２１のいずれか一項に記載の液体供給システム。 The control unit is arranged inside the catalyst or downstream of the catalyst, and based on the concentration detected by a plurality of detection units (70) capable of detecting the concentration of ambient oxygen, the controller detects The liquid supply system according to any one of claims 19 to 21, which estimates the distribution.
  23. 　前記制御部は、前記触媒の内部または前記触媒の下流に設けられ周囲の前記反応物質の濃度を検出可能な複数の検出部（７０）により検出した濃度に基づき、前記触媒の径方向の前記反応物質の分布を推定する請求項１９～２２のいずれか一項に記載の液体供給システム。 The control unit controls the reaction in the radial direction of the catalyst based on the concentration detected by a plurality of detection units (70) provided inside the catalyst or downstream of the catalyst and capable of detecting the concentration of the surrounding reactant. The liquid supply system according to any one of claims 19 to 22, which estimates the distribution of substances.
  24. 　前記制御部は、前記触媒の径方向の前記反応物質の分布を推定し、推定した分布の偏りが大きい程、前記上帯電部への電圧の印加量を大きくする請求項１９～２３のいずれか一項に記載の液体供給システム。 The control unit estimates the distribution of the reactant in the radial direction of the catalyst, and increases the amount of voltage applied to the upper charging unit as the estimated distribution is biased. The liquid supply system according to one item.
  25. 　前記液体供給部の下流に設けられた触媒（１０）の上流側に設けられ、電圧の印加により帯電する下帯電部（３４１）をさらに備える請求項１～２４のいずれか一項に記載の液体供給システム。 The liquid according to any one of claims 1 to 24, further comprising a lower charging section (341) provided on the upstream side of the catalyst (10) provided on the downstream side of the liquid supply section and charged by application of a voltage. Supply system.
  26. 　前記制御部は、液体の噴霧が前記下帯電部を通過するよりも前に、噴霧形成時に液体に帯電させた電荷と同じ極性の電荷を前記下帯電部に帯電させる請求項２５に記載の液体供給システム。 26. The liquid according to claim 25, wherein the control unit charges the lower charging unit with a charge having the same polarity as a charge charged in the liquid during spray formation, before the spray of the liquid passes through the lower charging unit. Supply system.
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008261266A (en) * 2007-04-11 2008-10-30 Toyota Motor Corp Exhaust emission control device for internal combustion engine
JP2016065501A (en) * 2014-09-25 2016-04-28 株式会社デンソー Fuel supply apparatus and fuel supply apparatus control method
JP2018001103A (en) * 2016-07-04 2018-01-11 株式会社デンソー Injection valve

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008261266A (en) * 2007-04-11 2008-10-30 Toyota Motor Corp Exhaust emission control device for internal combustion engine
JP2016065501A (en) * 2014-09-25 2016-04-28 株式会社デンソー Fuel supply apparatus and fuel supply apparatus control method
JP2018001103A (en) * 2016-07-04 2018-01-11 株式会社デンソー Injection valve

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