WO2011070955A1 - Moteur, véhicule et bateau comprenant ledit moteur - Google Patents

Moteur, véhicule et bateau comprenant ledit moteur Download PDF

Info

Publication number
WO2011070955A1
WO2011070955A1 PCT/JP2010/071488 JP2010071488W WO2011070955A1 WO 2011070955 A1 WO2011070955 A1 WO 2011070955A1 JP 2010071488 W JP2010071488 W JP 2010071488W WO 2011070955 A1 WO2011070955 A1 WO 2011070955A1
Authority
WO
WIPO (PCT)
Prior art keywords
passage
exhaust
downstream
catalyst
upstream
Prior art date
Application number
PCT/JP2010/071488
Other languages
English (en)
Japanese (ja)
Inventor
嗣教 粉川
Original Assignee
ヤマハ発動機株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ヤマハ発動機株式会社 filed Critical ヤマハ発動機株式会社
Priority to BR112012012777A priority Critical patent/BR112012012777A2/pt
Priority to CN201080056390.4A priority patent/CN102686844B/zh
Priority to EP10835876.3A priority patent/EP2511494A4/fr
Publication of WO2011070955A1 publication Critical patent/WO2011070955A1/fr

Links

Images

Classifications

    • 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
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/24—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
    • F01N3/30—Arrangements for supply of additional air
    • 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
    • F01N1/00—Silencing apparatus characterised by method of silencing
    • F01N1/003—Silencing apparatus characterised by method of silencing by using dead chambers communicating with gas flow passages
    • 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
    • F01N1/00—Silencing apparatus characterised by method of silencing
    • F01N1/06—Silencing apparatus characterised by method of silencing by using interference effect
    • 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
    • F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
    • F01N13/08—Other arrangements or adaptations of exhaust conduits
    • 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
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/24—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
    • F01N3/30—Arrangements for supply of additional air
    • F01N3/34—Arrangements for supply of additional air using air conduits or jet air pumps, e.g. near the engine exhaust port
    • 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
    • B01D53/9445—Simultaneously removing carbon monoxide, hydrocarbons or nitrogen oxides making use of three-way catalysts [TWC] or four-way-catalysts [FWC]
    • 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
    • F01N2210/00—Combination of methods of silencing
    • F01N2210/02—Resonance and interference
    • 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
    • F01N2470/00—Structure or shape of gas passages, pipes or tubes
    • F01N2470/30—Tubes with restrictions, i.e. venturi or the like, e.g. for sucking air or measuring mass flow
    • 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
    • F01N2490/00—Structure, disposition or shape of gas-chambers
    • F01N2490/14—Dead or resonance chambers connected to gas flow tube by relatively short side-tubes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
    • Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies

Definitions

  • the present invention relates to an engine (internal combustion engine), and a vehicle and a ship provided with the same.
  • An engine (internal combustion engine) equipped with a catalyst that purifies exhaust gas and a secondary air supply system that supplies air to an exhaust passage is known.
  • a three-way catalyst is provided in the exhaust passage.
  • the secondary air supply device is connected to the exhaust passage so as to supply secondary air upstream and downstream of the catalyst. Secondary air is air supplied without passing through the combustion chamber of the engine.
  • the catalyst mainly functions as a reduction catalyst for reducing NOx, but also functions as an oxidation catalyst. That is, the secondary air supplied downstream from the catalyst once flows into the catalyst due to the pulsation of the exhaust gas and then flows downstream. At this time, the catalyst also functions as an oxidation catalyst that oxidizes CO and THC, and purifies NOx, CO, and THC in the exhaust gas discharged from the engine.
  • the secondary air supply device is configured to supply secondary air also upstream of the catalyst. This is because the amount of CO and THC contained in the exhaust gas increases when the supply air-fuel ratio to the engine is set to the rich side during high speed and high load operation. At this time, by supplying secondary air upstream of the catalyst, the catalyst can function as an oxidation catalyst that mainly oxidizes CO and THC.
  • Patent Document 1 discloses two methods for supplying secondary air downstream from a catalyst. One is a method in which a reed valve is provided and exhaust pulsation in the exhaust passage is used. The remaining one is a method of forcibly supplying secondary air to the exhaust passage by providing an air pump instead of a reed valve.
  • the above two methods of supplying secondary air downstream from the catalyst will be compared.
  • the method using the exhaust pulsation does not need to drive the pump, and therefore the engine output loss is small.
  • this method has the following problems.
  • the average pressure in the exhaust passage becomes high.
  • the catalyst becomes a resistance, so the amplitude of the exhaust pulsation becomes small.
  • the magnitude of the resistance due to this catalyst increases as the engine goes into a high speed or high load state. That is, especially when the engine is operated at a high speed or a high load, the average pressure in the exhaust passage increases and the amplitude of the exhaust pulsation decreases. Thereby, a large negative pressure cannot be generated in the exhaust passage downstream of the catalyst. Therefore, a sufficient amount of secondary air cannot be supplied into the exhaust passage downstream of the catalyst, particularly when the engine is operated at a high rotation or high load.
  • the method using an air pump can supply secondary air even when the engine is operated at a high speed or a high load.
  • the load on the air pump increases as the engine speed increases or the load increases. Since the air pump is driven by the engine, the loss of the engine output increases as the engine goes into a high speed or high load state.
  • the inventor of the present application has found a shock wave that propagates downstream in the exhaust passage when the exhaust port is opened. And it was thought that air could be supplied even in a high load state by utilizing the negative pressure generated behind the shock wave. However, this shock wave is generated in the vicinity of the exhaust port, propagates downstream, attenuates and disappears. For this reason, it cannot be used to generate a negative pressure downstream of the catalyst.
  • the inventor of the present application considered that another new shock wave is generated in the exhaust passage to generate a new negative pressure.
  • This nozzle has a convergent portion whose flow passage cross-sectional area becomes smaller toward the downstream side of the flow passage, a divergent portion whose flow passage cross-sectional area becomes larger downstream of the convergent portion, and the convergent portion and the divergent portion. And a throat portion between.
  • the exhaust passage is provided with a convergent portion having a smaller flow passage cross-sectional area at the downstream end than the flow passage cross-sectional area at the upstream end, and further to the exhaust passage downstream from the convergent portion.
  • a divergent portion having a flow path cross-sectional area at the downstream end larger than that at the upstream end was provided.
  • the pressure ratio (P / P0) between the pressure P0 of the convergent part and the pressure P of the divergent part does not reach the critical pressure ratio simply by providing the convergent part and the divergent part in the exhaust passage. A new shock wave could not be generated.
  • the inventor of the present application has further studied the engine, and as a result, the shock wave propagating downstream in the exhaust passage when the exhaust port is opened propagates at a higher speed than the exhaust gas flowing into the exhaust passage from the combustion chamber at that time. I found out. Furthermore, the inventor considered a structure for increasing the pressure P0 of the convergent portion, paying attention to the difference between the velocity of the shock wave and the velocity of the exhaust gas.
  • the structure includes a branch portion that once branches the preceding shock wave from the exhaust passage and returns it to the exhaust passage again. As the pressure P0 in the convergent portion increases, a new shock wave is generated in the divergent portion. Then, a negative pressure is generated behind the shock wave, that is, upstream from the divergent portion. Furthermore, the inventor of the present application has considered a structure for supplying air using the negative pressure generated upstream from the divergent portion.
  • the structure includes a first passage connected upstream of the divergence portion of the exhaust passage and a second passage connected to the first passage.
  • an engine according to an embodiment of the present invention includes a combustion chamber in which an exhaust port is formed, an exhaust valve that opens and closes the exhaust port, and an exhaust passage that guides exhaust gas discharged from the combustion chamber through the exhaust port. And an air supply device for supplying air.
  • the exhaust device is provided in the exhaust passage, and is provided with a convergent portion having a flow passage cross-sectional area at the downstream end smaller than a flow passage cross-sectional area at the upstream end, provided downstream of the convergent portion in the exhaust passage, and A divergent portion having a flow passage cross-sectional area larger than a flow passage cross-sectional area at the upstream end, and the exhaust passage at a higher speed than exhaust gas flowing from the combustion chamber into the exhaust passage when the exhaust port is opened. And a branch portion for branching the shock wave from the exhaust passage upstream from the divergent portion and propagating the shock wave to the exhaust passage again.
  • the air supply device includes a first reed valve that allows an air flow from an upstream end to a downstream end to pass therethrough, and a downstream end is connected to the upstream side of the divergent portion of the exhaust passage, and an upstream end is And a second passage connected downstream of the first reed valve of the first passage.
  • the exhaust device causes the exhaust gas flowing into the exhaust passage from the combustion chamber to pass through the convergent portion and collide with a shock wave propagated through the branch portion between the branch portion and the divergent portion.
  • the pressure of the exhaust gas is increased at the convergent portion, and a new shock wave is generated by passing the exhaust gas whose pressure has been increased through the divergent portion.
  • the air supply device uses the negative pressure generated in the exhaust passage upstream of the divergent portion due to the newly generated shock wave to supply air to the first passage through the first reed valve.
  • the air introduced is supplied to the second passage by using a positive pressure generated in the exhaust passage upstream of the divergent portion.
  • the shock wave preceding the exhaust gas is once branched at the branching portion and returned to the exhaust passage again.
  • the shock wave can be delayed in time at the branch portion, and the shock wave can collide with the exhaust gas in the exhaust passage, thereby increasing the pressure of the exhaust gas.
  • the pressure ratio (P / P0) between the pressure P0 of the convergent portion and the pressure P of the divergent portion easily reaches the critical pressure ratio. That is, when high-pressure exhaust gas passes through the divergent portion, a new shock wave (shock wave different from the shock wave generated when the exhaust port is opened) is generated.
  • a large negative pressure is generated upstream of the new shock wave, that is, upstream of the divergent portion.
  • Secondary air can be introduced into the first passage from the upstream end of the first passage using the large negative pressure.
  • Secondary ventilation is air outside the engine that does not pass through the combustion chamber.
  • FIG. 2 is a schematic diagram showing a configuration of a convergent-divergent nozzle.
  • 6 is a graph showing the relationship between the pressure ratio of a convergent-divergent nozzle and the Mach number. It is sectional drawing for demonstrating the advancing state of a shock wave and waste gas.
  • 4A shows an initial state of the exhaust stroke
  • FIG. 4B shows a state when the shock wave propagates in the branch path
  • FIG. 4C shows a state when the shock wave reflected by the branch path collides with the exhaust gas.
  • It is a schematic diagram of the exhaust passage etc. which shows the path where a shock wave advances, and the path where exhaust gas advances.
  • FIG. 3 is a schematic view schematically showing a photograph of the inside of a convergent-divergent nozzle taken by a schlieren photographing method. It is a graph which shows the relationship between the exhaust gas flow velocity at the time of acceleration of a shock wave, and exhaust gas pressure. It is a graph which shows the relationship between the exhaust gas flow velocity at the time of acceleration of a shock wave, and exhaust gas temperature. It is a figure for demonstrating the effect
  • FIG. 9A is a diagram showing an example of the relationship between the crank angle and the pressure in the exhaust passage.
  • FIG. 9B is a diagram illustrating an example of the relationship between the crank angle and the mass flow rate of the gas in the first passage.
  • FIG. 9A is a diagram showing an example of the relationship between the crank angle and the pressure in the exhaust passage.
  • FIG. 9B is a diagram illustrating an example of the relationship between the crank angle and the mass flow rate of the gas in the first passage.
  • FIG. 9C is a diagram showing an example of the relationship between the crank angle, the exhaust passage, and the oxygen concentration in each part of the secondary air supply device. It is sectional drawing which shows structures, such as an exhaust passage of the engine which concerns on 2nd Embodiment of this invention. It is sectional drawing which shows structures, such as an exhaust passage of the engine which concerns on 3rd Embodiment of this invention. It is sectional drawing for demonstrating structures, such as an exhaust apparatus of the engine which concerns on 4th Embodiment of this invention. It is sectional drawing for demonstrating structures, such as an exhaust apparatus of the engine which concerns on 5th Embodiment of this invention. It is a schematic perspective view for demonstrating the structural example of a catalyst.
  • FIG. 17A shows the initial state of the exhaust stroke
  • FIG. 17B shows the state when the shock wave propagates into the individual exhaust passages (branch passages) of other cylinders
  • FIG. 17C shows the shock wave and exhaust gas reflected by the branch passage. Shows the state when the crashes.
  • FIG. 17B shows the initial state of the exhaust stroke
  • FIG. 17B shows the state when the shock wave propagates into the individual exhaust passages (branch passages) of other cylinders
  • FIG. 17C shows the shock wave and exhaust gas reflected by the branch passage. Shows the state when the crashes.
  • It is sectional drawing of the exhaust passage etc. which show a modification.
  • the method is as follows. (1) The shock wave propagating ahead of the exhaust gas is branched. (2) The branched shock wave is delayed in time and collided with the exhaust gas to increase the pressure of the exhaust gas. (3) The exhaust gas whose pressure has been increased passes through the divergent portion and is accelerated to supersonic speed to generate a new shock wave. (4) A negative pressure is generated in the exhaust passage upstream of the divergent portion. (5) Utilizing the negative pressure, secondary air is introduced into the first passage of the secondary air supply device connected upstream from the divergent portion. (6) Secondary air is supplied to the second passage of the secondary air supply device using positive pressure generated in the exhaust passage upstream of the divergent section.
  • FIG. 1 is a cross-sectional view showing a configuration of an engine according to a first embodiment of the present invention.
  • the engine 1 includes a cylinder body 3, a cylinder head 4 provided at one end thereof, and a piston 5 that reciprocates within the cylinder body 3.
  • a combustion chamber 10 is formed inside the cylinder body 3 and the cylinder head 4. More specifically, the combustion chamber 10 is defined by the inner wall of the cylinder body 3, the inner wall of the cylinder head 4, and the surface of the piston 5 (surface facing the cylinder head 4).
  • the piston 5 is coupled to the crankshaft 16 via a connecting rod 15.
  • the crankshaft 16 is accommodated in a crankcase 17 coupled to the cylinder body 3.
  • the reciprocating motion of the piston 5 is transmitted to the crankshaft 16 by the connecting rod 15 so that the crankshaft 16 rotates.
  • the engine 1 is a four-cycle gasoline internal combustion engine.
  • the engine 1 is a single cylinder engine.
  • the engine 1 may be an air-cooled engine or a water-cooled engine.
  • a downstream portion 6a of the intake passage 6 and an upstream portion 7a of the exhaust passage 7 are formed.
  • the cylinder head 4 includes an intake valve 8 that opens and closes the intake port 8a, an exhaust valve 9 that opens and closes the exhaust port 9a, and a valve operating device (not shown) for driving the intake valve 8 and the exhaust valve 9.
  • a valve operating device (not shown) for driving the intake valve 8 and the exhaust valve 9.
  • one downstream portion 6 a of the intake passage 6 and one upstream portion 7 a of the exhaust passage 7 are provided for each combustion chamber 10.
  • a plurality of intake ports 8a, intake valves 8, exhaust ports 9a and / or exhaust valves 9 may be provided for one combustion chamber.
  • An injector 2 that injects fuel is attached to the cylinder head 4. Although illustration is omitted, the cylinder head 4 is provided with a spark plug.
  • a throttle valve 11 is disposed in the intake passage 6 upstream of the downstream portion 6a.
  • the throttle valve 11 may be mechanically coupled (for example, coupled via a cable) to an operation member operated by an operator. Further, there is no such mechanical coupling, and the throttle valve 11 may be electronically controlled by a motor.
  • the engine 1 further includes an exhaust device 50.
  • the exhaust device 50 includes a first exhaust pipe 51 connected to the cylinder head 4, a second exhaust pipe 52 connected to the first exhaust pipe 51, and a third exhaust pipe connected to the second exhaust pipe 52. 53.
  • the first exhaust pipe 51 is attached to the cylinder head 4 with bolts 12.
  • the third exhaust pipe 53 has an exhaust chamber 55 formed therein.
  • the exhaust device 50 has an exhaust passage 7 connected to the outside through the exhaust chamber 55 from the upstream portion 7a.
  • a first catalyst 21 and a second catalyst 22 are disposed in the exhaust passage 7.
  • the second catalyst 22 is disposed downstream of the first catalyst 21.
  • a gap is provided between the first catalyst 21 and the second catalyst 22.
  • a muffler (not shown) is connected downstream of the exhaust chamber 55. The exhaust gas flowing into the exhaust chamber 55 passes through the silencer and is discharged outside.
  • the exhaust chamber 55 is provided with an oxygen concentration sensor 19 that detects the amount of oxygen in the exhaust gas.
  • the engine 1 includes an ECU (electronic control unit) 20 that is a control device.
  • the ECU 20 controls the fuel injection amount of the injector 2 or the ignition timing of the ignition plug based on the rotational speed of the engine 1, the opening of the throttle valve 11, or a signal detected by the oxygen concentration sensor 19.
  • the ECU 20 controls the fuel injection amount of the injector 2 so that the air-fuel ratio of the air-fuel mixture sucked into the engine 1 becomes the stoichiometric air-fuel ratio (stoiciometry).
  • a branch pipe 30 is provided upstream of the first exhaust pipe 51.
  • One end of the branch pipe 30 is an open end connected to the first exhaust pipe 51, and the other end is a closed end closed.
  • the closed end forms a reflection portion 31b that reflects a shock wave, which will be described later.
  • the branch pipe 30 may be integrally formed with the first exhaust pipe 51.
  • the branch pipe 30 may be formed separately from the first exhaust pipe 51 and may be fixed to the first exhaust pipe 51.
  • the 1st exhaust pipe 51 and the branch pipe 30 may be welded, and may be fixed by fastening members (not shown), such as a volt
  • the closed end of the branch pipe 30 is formed so that the flow path cross-sectional area is larger than the open end.
  • the shape of the branch pipe 30 is not limited to the shape shown in FIG. That is, the cross-sectional area of the closed end of the branch pipe 30 may be equal to the cross-sectional area of the open end or may be smaller than the cross-sectional area of the open end.
  • a branch part 31 is formed inside the branch pipe 30.
  • One end of the branch portion 31 is an open end connected to the exhaust passage 7, and the other end is a closed end.
  • the inlet 31a of the branch portion 31 (that is, the communicating portion with the exhaust passage 7) has a flow passage cross-sectional area through which a shock wave propagating through the exhaust passage 7 can also propagate into the branch portion 31. It is formed to have.
  • X is the center line of the flow path cross section of the inlet 31a of the branch part 31. The center line is a line passing through the center of gravity of the cross section of the flow path.
  • a convergent-divergent nozzle 40 is provided between the branch portion 31 and the first catalyst 21.
  • the convergent-divergent nozzle 40 is commonly referred to as a de Laval nozzle.
  • the convergent-divergent nozzle 40 accelerates the flow velocity of the exhaust gas flowing through the exhaust passage 7 from subsonic to supersonic.
  • the convergent-divergent nozzle 40 is formed by a convergent part 41, a throat part 42, and a divergent part 43.
  • the convergent portion 41 is a portion where the flow path cross-sectional area gradually decreases as it goes downstream.
  • the divergent portion 43 is a portion where the flow path cross-sectional area gradually increases toward the downstream.
  • the throat portion 42 is a portion disposed between the convergent portion 41 and the divergent portion 43, and is the portion having the smallest channel cross-sectional area.
  • the engine 1 further includes a secondary air supply device 70 that supplies air to the exhaust passage 7 of the exhaust device 50.
  • the secondary air supply device 70 includes a reed valve 74 (a check valve), a first secondary air supply pipe 76, and a second secondary air supply pipe connected to the first secondary air supply pipe 76. 77.
  • the reed valve 74 is coupled to the upstream end of the first secondary air supply pipe 76.
  • the downstream end of the first secondary air supply pipe 76 is connected between the branch pipe 30 and the convergent-divergent nozzle 40 in the first exhaust pipe 51.
  • the first secondary air supply pipe 76 is connected to an air cleaner 78 via a reed valve 74 and an air amount control valve 75.
  • the reed valve 74 prevents exhaust gas from flowing upstream from the first secondary air supply pipe 76.
  • the reed valve 74 is configured to open when negative pressure is generated in the exhaust passage 7 and to flow air downstream of the first secondary air supply pipe 76.
  • the air amount control valve 75 is for adapting the amount of secondary air to the operating state of the engine 1.
  • the air amount control valve 75 includes an actuator, a servo motor, a solenoid, or the like that uses an intake negative pressure as a power source.
  • the opening degree of the air amount control valve 75 is controlled by the ECU 20. When the opening degree of the throttle valve 11 is smaller than a predetermined angle, the ECU 20 closes the air amount control valve 75 or reduces the opening degree of the throttle valve 11.
  • the predetermined angle is set in advance and is stored in the ECU 20. Further, the ECU 20 increases the opening degree of the air amount control valve 75 when the opening degree of the throttle valve 11 is larger than the predetermined opening degree.
  • the air amount control valve 75 increases or decreases in opening corresponding to the opening of the throttle valve 11.
  • the secondary air can be supplied to the exhaust passage 7 at an appropriate flow rate without excess or deficiency.
  • the air amount control valve 75 is not always necessary and can be omitted.
  • the upstream end of the second secondary air supply pipe 77 is connected to the first secondary air supply pipe 76 between its downstream end and the reed valve 74.
  • the downstream end of the second secondary air supply pipe 77 is connected between the first catalyst 21 and the second catalyst 22 in the second exhaust pipe 52. More specifically, the downstream end of the second secondary air supply pipe 77 is connected to the second exhaust pipe 52 at a position closer to the first catalyst 21 than to the second catalyst 22.
  • the secondary air supply device 70 has a first passage 71 and a second passage 72.
  • the first passage 71 is a passage from the reed valve 74 to the exhaust passage 7 and is a passage formed by the first secondary air supply pipe 76. That is, the first passage 71 connects the reed valve 74 and a portion between the inlet 31 a of the branch portion 31 of the exhaust passage 7 and the divergent portion 43.
  • the second passage 72 is a passage from the first passage 71 to the exhaust passage 7 in the second exhaust pipe 52, and is a passage formed by the second secondary air supply pipe 77. That is, the second passage 72 connects the first passage 71 and the portion of the exhaust passage 7 between the first catalyst 21 and the second catalyst 22.
  • the “upstream” and “downstream” of the second passage 72 are defined by the connection portion 72 b (hereinafter “downstream end 72 b”) from the connection portion 72 a (hereinafter also referred to as “upstream end 72 a”) to the first passage 71. It also means upstream and downstream in the direction of flow to.
  • the first and second passages 71 and 72 are designed so that L1 ⁇ L2. Energy loss is synonymous with pressure loss in a gas flow path.
  • Such an energy loss relationship can be verified as follows, for example. That is, the second passage 72 is closed (for example, closed at the downstream end 72b), air is allowed to flow through the flow path 61, and the flow coefficient k1 at the downstream end (connection portion 71b) of the flow path 61 is measured.
  • the first passage 71 is closed (for example, closed at the upstream end 71a), air is allowed to flow through the flow path 62, and the flow coefficient k2 is measured at the downstream end (connection portion 71b) of the flow path 62. At this time, if k1> k2 is satisfied, L11 ⁇ L12 is satisfied. Any of the following methods may be used to flow air through the flow paths 61 and 62.
  • the first method is a method of sending air into the flow paths 61 and 62 by connecting a pump to the upstream ends of the flow paths 61 and 62.
  • the second method is a method of sucking air from the flow paths 61 and 62 by connecting a pump to the downstream ends of the flow paths 61 and 62.
  • the flow path 61 is a flow path from the atmosphere release position to the connection portion 71b.
  • the energy loss L1 is the amount of energy lost when the gas flows from the open position to the connecting portion 72a of the second passage 72 to the first passage 71.
  • the flow coefficient is the ratio of the actually flowed air flow rate to the theoretical air amount determined by the actual opening area and the differential pressure. That is, it is obtained by dividing the actual air flow rate by the theoretical air flow rate.
  • Examples of energy loss when gas flows through pipes are losses due to friction with the wall surface, losses at the inlet or outlet of the pipe, losses due to bends in the pipe, losses due to changes in the cross-sectional area of the pipe, losses due to valves, etc. including.
  • the loss due to the change in the channel cross-sectional area is a loss when the cross-sectional area suddenly increases or decreases, and a loss when the cross-sectional area increases or decreases gradually.
  • the loss due to friction with the wall surface increases as the surface roughness of the wall surface increases, the length of the pipe line increases, and the cross-sectional area of the pipe line decreases.
  • the loss due to the bending of the pipe increases as the ratio of the pipe diameter divided by the radius of curvature of the bending increases and the angle of bending increases.
  • the loss due to the valve varies depending on the type and opening of the valve and needs to be obtained through experiments. Reed valve loss is measured, for example, by measuring the relationship between the pressure difference between the upstream and downstream of the reed valve, the opening of the reed valve (cross-sectional area of the flow path), and the mass flow rate. It is obtained by deriving the relationship between the pressure difference and the loss factor.
  • FIG. 2 is a schematic diagram of a general convergent-divergent nozzle.
  • the flow path cross-sectional area A1 at the upstream end of the convergent portion 41, the flow path cross-sectional area A2 of the throat portion 42, and the flow path cross-sectional area A3 at the downstream end of the divergent portion 43 include There is a relationship.
  • the channel cross-sectional area A2 of the throat part 42 is the same as the channel cross-sectional area at the downstream end of the convergent part 41 and the channel cross-sectional area at the upstream end of the divergent part 43.
  • the channel cross-sectional areas of the convergent part 41 and the divergent part 43 change at a constant rate along the flow direction.
  • the convergent part 41 and the divergent part 43 may have other shapes.
  • the convergent-divergent nozzle 40 is formed so as to satisfy the conditions represented by the following formulas (1) and (2).
  • Mach 1 that is, the speed of sound
  • the exhaust gas can be accelerated to supersonic speed in the divergent portion 43.
  • Equation (1) shows the relationship between the exhaust pipe shape and the Mach number in a one-dimensional flow with viscous friction.
  • Equation (2) represents ⁇ in Equation (1).
  • M is the Mach number
  • A is the cross-sectional area of the exhaust pipe in an arbitrary cross section
  • D is the pipe equivalent diameter in the above-mentioned arbitrary cross section
  • ⁇ is the specific heat ratio
  • x is the distance in the flow direction
  • f the coefficient of friction.
  • P0 is the full pressure upstream of the throat portion 42
  • P is the static pressure downstream of the throat portion 42.
  • the speed at the throat portion 42 becomes equal to or higher than the sound speed (Mach 1).
  • the speed at the divergent unit 43 becomes supersonic. Therefore, when the total pressure P0 is increased so that P / P0 becomes smaller than the critical pressure ratio, a supersonic flow can be formed in the convergent-divergent nozzle 40.
  • FIGS. 4A to 4C schematically show the engine 1 including the exhaust device 50.
  • FIG. 4A to 4C the same or equivalent members as those shown in FIGS. 1 and 2 are denoted by the same reference numerals.
  • FIG. 4A when the exhaust port 9a is opened in the exhaust stroke of the engine 1, high-pressure exhaust gas 36 is jetted from the combustion chamber 10 to the upstream portion 7a of the exhaust passage 7 through the exhaust port 9a.
  • the speed of the exhaust gas 36 reaches the sonic speed, and the shock wave 35 flows into the upstream portion 7a of the exhaust passage 7. Will occur.
  • the exhaust port 9a opens greatly, the amount of exhaust gas flowing out to the upstream portion 7a of the exhaust passage 7 increases, but the exhaust gas speed decreases. Further, the exhaust gas is decelerated as it travels upstream of the exhaust passage 7.
  • the shock wave 35 propagates from the upstream portion 7a of the exhaust passage 7 to the inside of the first exhaust pipe 51, and further propagates toward the downstream at high speed.
  • the exhaust gas 36 travels behind the exhaust passage 7 at a speed lower than that of the shock wave 35.
  • the shock wave 35 traveling inside the first exhaust pipe 51 is converted into a shock wave propagating through the exhaust passage 7 and a shock wave propagating through the branch portion 31 when passing through the inlet 31a of the branch portion 31.
  • the exhaust passage 7 and the branching portion 31 proceed independently of each other.
  • the shock wave 35 traveling through the exhaust passage 7 attenuates and disappears after passing through the convergent-divergent nozzle 40.
  • the shock wave 35 traveling along the branching portion 31 is reflected by the reflecting portion 31 b of the branching portion 31, and travels back through the branching portion 31 and returns to the exhaust passage 7.
  • the time when the reflected shock wave 35 returns from the branch portion 31 to the exhaust passage 7 is the same as or later than the time when the high-pressure exhaust gas 36 reaches the center of the inlet 31 a of the branch portion 31.
  • the length of the branching portion 31 is set. Therefore, the shock wave 35 and the exhaust gas 36 collide with each other in the exhaust passage 7 upstream of the divergent section 43 and in the inlet 31a of the branch section 31 or downstream thereof.
  • the total pressure upstream of the throat portion 42 of the convergent-divergent nozzle 40 can be increased.
  • a state in which the pressure ratio P / P0 is smaller than the critical pressure ratio can be realized, and a supersonic flow can be formed in the convergent-divergent nozzle 40.
  • FIG. 5 is a schematic diagram of the exhaust passage 7 and the like showing the path of the shock wave and the path of the exhaust gas.
  • the distance (flow path length) from the center 9ac of the exhaust port 9a to the flow path cross-sectional center line X of the branch portion inlet 31a is Le
  • the distance (flow) between the flow path cross-sectional center line Y of the exhaust passage 7 and the reflecting part 31b. (Path length) is Ls.
  • the velocity of the exhaust gas 36 is Ve
  • the propagation velocity of the shock wave 35 is Vs.
  • a time T1 from when the exhaust port 9a is opened until the exhaust gas 36 reaches the inlet 31a is expressed by Expression (3).
  • the time T2 from when the exhaust port 9a is opened until the shock wave 35 is reflected by the reflecting portion 31b and reaches the center line Y of the exhaust passage 7 is expressed by Expression (4).
  • T1 Le / Ve (3)
  • T2 (Le + 2Ls) / Vs (4) If T1 ⁇ T2, the reflected shock wave 35 and the exhaust gas 36 collide. That is, if Le / Ve ⁇ (Le + 2Ls) / Vs, the reflected shock wave 35 and the exhaust gas 36 collide with each other in the exhaust passage 7 upstream of the divergent section 43 and at the inlet 31a of the branch section 31 or downstream thereof.
  • the maximum speed of the exhaust gas 36 may be regarded as the speed Ve, and the average speed may be regarded as the speed Ve.
  • the maximum propagation velocity of the reflected shock wave 35 may be regarded as the propagation velocity Vs, and the average propagation velocity may be regarded as the propagation velocity Vs.
  • the distance (flow path length) from the flow path cross-sectional center line X of the branch portion inlet 31a to the upstream end of the divergent portion 43 is Ld, and the time from the opening of the exhaust port 9a to closing is tv.
  • a time T3 from when the exhaust port 9a is opened until the tail end of the exhaust gas 36 reaches the upstream end of the divergent portion 43 is expressed by Expression (5).
  • a time T4 from when the exhaust port 9a is opened until the shock wave 35 is reflected by the reflecting portion 31b and reaches the upstream end of the divergent portion 43 is expressed by Expression (6).
  • T3 tv + (Le + Ld) / Ve (5)
  • T4 (Le + 2Ls + Ld) / Vs (6) If T4 ⁇ T3, the reflected shock wave 35 and the exhaust gas 36 can collide before the entire exhaust gas 36 passes through the throat portion 42. That is, if (Le + 2Ls + Ld) / Vs ⁇ tv + (Le + Ld) / Ve, the reflected shock wave 35 and the exhaust gas 36 can collide before the exhaust gas 36 passes through the throat portion 42.
  • the distance Ls between the flow path cross-sectional center line Y of the exhaust passage 7 and the reflecting portion 31b is relatively small, the attenuation of the shock wave 35 at the branch portion 31 is suppressed. Therefore, for example, the distance Ls may be smaller than the distance Le.
  • the pressure of the exhaust gas is increased by compression in the convergent part 41.
  • the pressure of the exhaust gas 36 in the convergent portion 41 is further increased by the collision between the shock wave 35 and the exhaust gas 36.
  • the total pressure P0 upstream of the inlet of the convergent-divergent nozzle 40 increases, and accordingly, the ratio P / P0 between the total pressure P0 upstream of the inlet and the downstream static pressure P of the throat portion is the critical pressure ratio 0. Less than .528.
  • the speed of the exhaust gas 36 reaches the speed of sound at the throat portion 42.
  • FIG. 6 is a schematic view schematically showing a photograph of the inside of the convergent-divergent nozzle taken by the schlieren photographing method.
  • a new shock wave is generated at the convergent-divergent nozzle 40.
  • a traveling shock wave 35b is accelerated when passing through the divergent section 43 of the convergent-divergent nozzle 40.
  • an expansion wave 35c traveling in the opposite direction to the traveling shock wave 35b is generated.
  • the traveling shock wave 35b is accelerated by the divergent portion 43, and at the same time, the expansion wave 35c travels in the opposite direction to the traveling shock wave 35b. Thereby, the pressure and temperature of the exhaust gas 36 existing between the traveling shock wave 35b and the expansion wave 35c are greatly reduced.
  • the exhaust gas has an atmospheric pressure or lower, that is, a negative pressure.
  • FIG. 7 shows the exhaust gas velocity (Exhaust Gas Velocity) and exhaust gas pressure (Exhaust Gas Pressure) at each point (Position) of the exhaust passage 7 immediately after the new shock wave 35b is generated by the convergent-divergent nozzle 40.
  • FIG. 8 shows the exhaust gas velocity (Exhaust Gas Velocity) and exhaust gas temperature (Exhaust Gas Temperature) at each point (Position) of the exhaust passage 7 immediately after a new shock wave 35b is generated by the convergent-divergent nozzle 40. .
  • the shock wave 35 reflected by the branch part 31 collides with the exhaust gas 36
  • the shock wave 35 propagates through the throat part 42 prior to the exhaust gas 36.
  • the exhaust gas 36 flows through the throat portion 42 without being reduced in speed by being pulled by the shock wave 35. Therefore, it is preferable to set the length of the portion of the throat portion 42 that continues with the same flow path cross-sectional area according to the engine.
  • the timing at which the shock wave 35b is accelerated in the divergent portion 43 in other words, the timing at which the pressure and temperature of the exhaust gas are lowered can be set according to the engine.
  • the pressure and temperature of the exhaust gas in the exhaust passage 7 can be significantly reduced as compared with the related art.
  • the operation of the secondary air supply device 70 will be described with reference to FIGS. 9A to 9C showing simulation results by the present inventors.
  • the secondary air supply device 70 efficiently supplies secondary air to a portion of the exhaust passage 7 downstream of the first catalyst 21 due to the negative pressure generated in the portion of the exhaust passage 7 upstream of the divergent portion 43.
  • FIG. 9A is a diagram showing an example of the relationship between the rotation angle (crank angle) of the crankshaft 16 (see FIG. 1) and the pressure in the exhaust passage 7 observed in the engine 1 of the present embodiment.
  • the exhaust port 9 a When the exhaust port 9 a is opened during the expansion stroke, high-pressure exhaust gas is discharged from the combustion chamber 10 into the exhaust passage 7. Therefore, as indicated by reference numeral 91, the exhaust passage 7 has a positive pressure. Thereafter, a large negative pressure is generated in the exhaust passage 7 as indicated by reference numeral 92 by the action of the convergent-divergent nozzle 40. Thereafter, positive pressure and negative pressure are alternately generated in the exhaust passage 7 due to exhaust pulsation, as indicated by reference numeral 93. Due to the influence of the large negative pressure generated by the operation of the convergent-divergent nozzle 40, the amplitude of this exhaust pulsation is larger than usual.
  • FIG. 9B shows the rotation angle (crank angle) of the crankshaft 16 (see FIG. 1) and the mass flow rate of gas (gas passing through the reed valve 74) in the first passage 71, which is observed in the engine 1 of the present embodiment. It is a figure which shows an example of a relationship. However, the mass flow rate represents the flow rate in the direction from the upstream end (reed valve 74 side) to the downstream end (exhaust passage 7 side) of the first passage 71 as a positive value, and the flow rate in the opposite direction is negative. It is expressed as a value.
  • the first passage 71 also has a negative pressure, and as a result, the reed valve 74 is opened.
  • the gas flows toward the first passage 71.
  • a flow path 61 (see FIG. 1) from the reed valve 74 through the first passage 71 to the exhaust passage 7 and a flow path 62 (through the second passage 72 from the downstream end 72b to the upstream end 72a to the exhaust passage 7 (see FIG. 1) is as described above. That is, the energy lost when the gas flows through the flow path 61 passing through the reed valve 74 is smaller than the energy lost when the gas flows through the flow path 62 passing through the second passage 72.
  • a flow path with a small energy loss has a higher gas flow rate than a flow path with a large energy loss, and therefore the flow rate flowing through the first passage 71 via the reed valve 74 is increased.
  • the amount of gas flowing from the outside of the engine 1 into the first passage 71 is larger than the amount of gas flowing from the second passage 72 to the first passage 71.
  • air (secondary air) outside the engine 1 containing a large amount of oxygen can be introduced into the first passage 71.
  • the reed valve 74 has a structure that allows only a gas flow in one direction to enter the first passage 71, a gas flow in the reverse direction is generated immediately after being opened and then immediately closed. This is the reason why negative mass flow values appear in FIG. 9B.
  • positive pressure is generated in the exhaust passage 7 upstream of the divergent portion 43 after air is introduced from the outside of the engine 1 into the first passage 71 (for example, reference numeral 95 in FIG. 9A), The air is pushed out. Since the reed valve 74 does not flow gas in the direction from the first passage 71 toward the outside of the engine 1, the air in the first passage 71 is pushed out to the second passage 72.
  • FIG. 9C is a diagram showing an example of the relationship between the rotation angle (crank angle) of the crankshaft 16 and the oxygen amount (oxygen concentration) in each part of the exhaust passage 7 and the secondary air supply device 70.
  • the curve 96a represents the oxygen concentration in the first passage 71 between the connection portion 72a of the second passage 72 and the exhaust passage 7 (for example, the measurement point a shown in FIG. 1).
  • a curve 96b represents the oxygen concentration in the vicinity of the intermediate portion of the second passage 72 (between the upstream end 72a and the downstream end 72b. For example, the measurement point b shown in FIG. 1).
  • curve 96c represents the oxygen concentration in the portion of the exhaust passage 7 downstream from the first catalyst 21 (between the first and second catalysts 21, 22; for example, the measurement point c shown in FIG. 1).
  • a curve 96d represents the oxygen concentration in the exhaust passage 7 (for example, the measurement point d shown in FIG. 1) upstream of the first passage connecting portion 71b.
  • the exhaust passage 7 upstream of the first passage connecting portion 71b with respect to the oxygen concentration in the exhaust passage 7 between the first and second catalysts 21 and 22 (for example, the measurement point c shown in FIG. 1). It can be seen that the oxygen concentration inside (for example, the measurement point d shown in FIG. 1) is lower. This indicates that secondary air is introduced downstream of the first catalyst 21 in the exhaust passage 7. Generally, if the oxygen concentration in the second passage 72 (for example, the measurement point b) is higher than the oxygen concentration in the exhaust passage 7 (for example, the measurement point d) upstream of the first passage connection portion 71b, The purpose of introducing secondary air is considered to have been achieved. If this can be confirmed, the purpose of supplying secondary air to the exhaust passage 7 between the first and second catalysts 21 and 22 has been achieved.
  • the oxygen concentration increases almost in synchronization with the timing of the positive pressure generation (positive pressure generation upstream of the divergent section 43) indicated by reference numeral 95 in FIG. 9A. is doing.
  • a sufficient amount of second gas is supplied to a portion of the exhaust passage 7 downstream from the first catalyst 21 without using a dedicated device for forcibly sending air into the exhaust passage 7. Secondary air can be supplied.
  • the secondary air is introduced from the outside using the negative pressure generated by utilizing the energy of the exhaust gas, and the introduced secondary air is also introduced into the first catalyst 21 using the positive pressure generated by the energy of the exhaust gas. Sending out downstream.
  • the pump action is realized using the energy of the exhaust gas, the loss of engine output can be reduced.
  • the exhaust passage 7 downstream of the first catalyst 21 is utilized by utilizing the large negative pressure associated with the generation of the shock wave and the sufficient positive pressure due to the exhaust pulsation. Secondary air can be supplied.
  • another pump device for supplying air can be used in combination. Even in this case, since the load applied to the pump can be reduced, the loss of engine output can be reduced.
  • the energy loss of the gas flowing in the flow path 61 from the upstream end 71 a to the downstream end 71 b of the first passage 71 is caused to flow from the downstream end 72 b of the second passage 72 to the downstream end 71 b of the first passage 71.
  • the energy loss of the gas flowing through the path 62 is smaller. That is, the flow coefficient of the first passage downstream end 71b when the second passage 72 is blocked and air flows from the first passage upstream end 71a blocks the first passage 71 upstream of the connection portion of the second passage 72.
  • the exhaust device 50 includes first and second catalysts 21 and 22 disposed in the exhaust passage 7 upstream and downstream of the downstream end 72b of the second passage 72, respectively.
  • the first catalyst 21 can mainly act as a reduction catalyst
  • the second catalyst 22 can mainly act as an oxidation catalyst.
  • the first catalyst 21 mainly acts as a reduction catalyst
  • fuel-rich exhaust gas may be guided to the first catalyst 21.
  • the second catalyst 22 when the second catalyst 22 functions as an oxidation catalyst, the second catalyst 22 only needs to be guided with an exhaust gas having a lean air-fuel ratio.
  • the 1st catalyst 21 and the 2nd catalyst 22 can cooperate and both a reduction reaction and an oxidation reaction can be performed, the harmful component in exhaust gas can be removed efficiently. Therefore, since the exhaust gas having the stoichiometric air / fuel ratio does not necessarily have to be guided to the first catalyst 21, the air / fuel ratio window capable of removing harmful components is widened. Therefore, it is not necessary to strictly control the air-fuel ratio.
  • the exhaust gas becomes high temperature, and this high-temperature exhaust gas may cause sintering of the catalysts 21 and 22.
  • the new shock wave 35b generated in the divergent section 43 generates a large negative pressure behind it. This negative pressure causes adiabatic expansion of the exhaust gas, thereby cooling the exhaust gas due to the effect of adiabatic cooling. That is, the exhaust gas is cooled until it reaches the first catalyst 21.
  • the fuel consumption can be suppressed, and at the same time, the catalysts 21 and 22 can be protected and detoxication of harmful components can be achieved.
  • the exhaust gas can be reduced in pressure and temperature even when the engine 1 is operating at a high load or at a high speed, the catalysts 21 and 22 can be protected.
  • FIG. 10 is a cross-sectional view showing the configuration of the exhaust passage and the like of the engine according to the second embodiment of the present invention.
  • the same reference numerals are given to the corresponding parts of the respective parts shown in FIG.
  • the engine 1 of the second embodiment includes a cylinder body 3, a cylinder head 4 provided at one end thereof, and a piston 5 that reciprocates within the cylinder body 3. Forms the combustion chamber 10.
  • the cylinder head 4 is provided with an intake valve 8 that opens and closes the intake port 8a, an exhaust valve 9 that opens and closes the exhaust port 9a, and a valve operating device for driving the intake valve 8 and the exhaust valve 9.
  • the engine 1 further includes an exhaust device 50 and a secondary air supply device 70 that supplies air to the exhaust passage 7 of the exhaust device 50.
  • the exhaust device 50 includes a first exhaust pipe 51 connected to the cylinder head 4, a second exhaust pipe 52 connected to the first exhaust pipe 51, and a third exhaust pipe connected to the second exhaust pipe 52. 53 and these exhaust pipes 51, 52, 53 form an exhaust passage 7.
  • the first catalyst 21 and the second catalyst 22 are arranged at an interval.
  • a branch pipe 30 is provided upstream of the first exhaust pipe 51.
  • a convergent-divergent nozzle 40 is provided between the branch pipe 30 and the first catalyst 21.
  • the secondary air supply device 70 includes a reed valve 74, a first secondary air supply pipe 76, and a second secondary air supply pipe 77 connected to the first secondary air supply pipe 76. Yes.
  • the first secondary air supply pipe 76 forms a first passage 71 that extends from the reed valve 74 to the exhaust passage 7.
  • the second secondary air supply pipe 77 forms a second passage 72 that extends from the first passage 71 to the exhaust passage 7 between the first and second catalysts 21 and 22.
  • the second reed valve 80 (check valve) is further provided in the second passage 72.
  • the reed valve 80 is configured to allow airflow in the direction from the upstream end 72a to the downstream end 72b of the second passage 71 to pass therethrough and to block airflow in the opposite direction.
  • Other configurations are the same as those in the first embodiment. Therefore, the detailed description of the second embodiment is substituted by FIGS. 1 to 9 and the detailed description of the first embodiment.
  • the reed valve 74 of the first passage 71 When negative pressure is generated in the exhaust passage 7 upstream of the divergent portion 43, the reed valve 74 of the first passage 71 is opened, and external air is introduced into the first passage 71. At this time, the reed valve 80 of the second passage 72 is closed, and the air flow from the downstream end 72b of the second passage 72 to the upstream end 72a is blocked.
  • the reed valve 74 of the first passage 71 is closed, and the reed valve 80 of the second passage 72 is opened.
  • the secondary air introduced into the first passage 71 passes through the second passage 72 and is sent to the exhaust passage 7 downstream of the first catalyst 21.
  • the air flow in the second passage 72 is limited in the direction from the upstream end to the downstream end. That is, the backflow of secondary air can be prevented.
  • negative pressure is generated upstream of the divergent portion 43
  • secondary air can be reliably introduced from the upstream end of the first passage 71, and positive pressure is generated upstream of the divergent portion 43.
  • the secondary air can be reliably supplied to the first and second catalysts 21 and 22.
  • FIG. 11 is a cross-sectional view showing a configuration of an engine exhaust passage and the like according to a third embodiment of the present invention.
  • the same reference numerals are assigned to the corresponding parts of the respective parts shown in FIG.
  • the engine 1 of the third embodiment includes a cylinder body 3, a cylinder head 4 provided at one end thereof, and a piston 5 that reciprocates within the cylinder body 3 (see FIG. 1). These form a combustion chamber 10.
  • the cylinder head 4 is provided with an intake valve 8 that opens and closes the intake port 8a, an exhaust valve 9 that opens and closes the exhaust port 9a, and a valve operating device for driving the intake valve 8 and the exhaust valve 9.
  • the engine 1 further includes an exhaust device 50 and a secondary air supply device 70 that supplies air to the exhaust passage 7 of the exhaust device 50.
  • the exhaust device 50 includes a first exhaust pipe 51 connected to the cylinder head 4, a second exhaust pipe 52 connected to the first exhaust pipe 51, and a third exhaust pipe connected to the second exhaust pipe 52. 53 and these exhaust pipes 51, 52, 53 form an exhaust passage 7.
  • the first catalyst 21 and the second catalyst 22 are arranged at an interval.
  • a branch pipe 30 is provided upstream of the first exhaust pipe 51.
  • a convergent-divergent nozzle 40 is provided between the branch pipe 30 and the first catalyst 21.
  • the branch pipe 30 is also used as the first secondary air supply pipe 76 that forms the first passage 71. That is, the dedicated first passage 71 is abolished, and the branch portion 31 is also used as the first passage 71. In other words, the first passage 71 is also used as the branch portion 31.
  • the second secondary air supply pipe 77 is connected to the branch pipe 30 that also serves as the first secondary air supply pipe 76, and the first and second catalysts 21 are connected from the branch section 31 (first passage 71). , 22 to the exhaust passage 7 is formed.
  • Other configurations are the same as those in the first embodiment. Therefore, the detailed description of the third embodiment is substituted by FIGS. 1 to 9 and the detailed description of the first embodiment.
  • a reed valve 74 is coupled to the end of the branch pipe 30 opposite to the exhaust passage 7, and an air amount control valve 75 and an air cleaner 78 are coupled to the upstream side thereof.
  • the reed valve 74 constitutes the reflection part 31 b of the branch part 31. That is, the shock wave from the exhaust passage 7 branches to the branch portion 31 (first passage 71), is reflected by the closed reed valve 74 (reflecting portion 31b), and again passes through the branch portion 31 (first passage 71). It is returned to the exhaust passage 7. This shock wave collides with the exhaust gas that travels in the exhaust passage 7 with a delay, and increases the pressure of the exhaust gas.
  • the reed valve 74 When the exhaust valve 9 is opened, the reed valve 74 is closed, and a shock wave can be reflected by the reed valve 74.
  • the reed valve 74 When negative pressure is generated in the exhaust passage 7 by the action of the convergent-divergent nozzle 40, the reed valve 74 is opened, and secondary air from the outside can be introduced into the first passage 71. Thereafter, when a positive pressure is generated in the exhaust passage 7 due to exhaust pulsation, the secondary air introduced into the first passage 71 is exhausted between the first and second catalysts 21 and 22 via the second passage 72. It is supplied to the passage 7.
  • a sufficient amount of air can be supplied to the exhaust passage 7 downstream of the first catalyst 21.
  • FIG. 12 is a cross-sectional view for explaining the configuration of an engine exhaust system and the like according to the fourth embodiment of the present invention.
  • the corresponding parts of the respective parts shown in FIG. 11 are given the same reference numerals.
  • the engine 1 of the fourth embodiment includes a cylinder body 3, a cylinder head 4 provided at one end thereof, and a piston 5 that reciprocates within the cylinder body 3 (see FIG. 1). These form a combustion chamber 10.
  • the cylinder head 4 is provided with an intake valve 8 that opens and closes the intake port 8a, an exhaust valve 9 that opens and closes the exhaust port 9a, and a valve operating device for driving the intake valve 8 and the exhaust valve 9.
  • the engine 1 further includes an exhaust device 50 and a secondary air supply device 70 that supplies air to the exhaust passage 7 of the exhaust device 50.
  • the exhaust device 50 includes a first exhaust pipe 51 connected to the cylinder head 4, a second exhaust pipe 52 connected to the first exhaust pipe 51, and a third exhaust pipe connected to the second exhaust pipe 52. 53 and these exhaust pipes 51, 52, 53 form an exhaust passage 7. In the exhaust passage 7, the first catalyst 21 and the second catalyst 22 are arranged at an interval. A branch pipe 30 is provided upstream of the first exhaust pipe 51.
  • the branch pipe 30 is also used as a first secondary air supply pipe 76 that forms the first passage 71.
  • the second secondary air supply pipe 77 is connected to the branch pipe 30 that also serves as the first secondary air supply pipe 76, and the first and second catalysts 21 and 22 are connected from the branch portion 31 (first passage 71).
  • a second passage 72 reaching the exhaust passage 7 is formed.
  • the branch pipe 30 is used as a part of a convergent-divergent nozzle. Other configurations are the same as those of the third embodiment (see FIG. 11). Therefore, the detailed description of the fourth embodiment is substituted with FIGS. 1 to 9 of the first embodiment, FIG. 11 of the third embodiment, and the detailed description thereof.
  • the convergent portion 41, the throat portion 42, and the divergent portion 43 are formed in the exhaust passage 7 downstream from the branch portion 31.
  • a branch portion 31 is provided that reflects the shock wave 35 generated in the early stage of the exhaust stroke and propagates again to the exhaust passage 7.
  • the branch portion 31 is viewed from different viewpoints, the flow passage cross-sectional area of the exhaust passage 7 is increased at the position of the branch portion 31. And downstream from that position, the flow path cross-sectional area becomes smaller.
  • the convergent portion 41 and the throat portion 42 are formed by the branch portion 31.
  • the flow passage cross-sectional area A5 of the exhaust passage 7 upstream from the branch portion inlet 31a and the flow passage cross-sectional area A7 of the exhaust passage 7 downstream from the branch portion inlet 31a are substantially equal, the following relationship is established. That is, the flow passage cross-sectional area obtained by adding the flow passage cross-sectional area A5 of the portion of the exhaust passage 7 located upstream of the branching portion inlet 31a and the flow passage cross-sectional area A4 of the branching portion 31 is downstream of the inlet 31a. Is larger than the cross-sectional area A7 of the portion of the exhaust passage 7 located at A4 + A5> A7.
  • the convergent portion 41 and the throat portion 42 are formed downstream of the inlet 31a. Therefore, the convergent-divergent nozzle 40 can be substantially formed simply by providing the divergent portion 43 downstream of the inlet 31a.
  • A6 represents the channel cross-sectional area of the divergent portion 43, and A7 ⁇ A6.
  • a portion between the inlet 31 a and the divergent portion 43 is a throat portion 42.
  • the throat part 42 may extend long along the flow path direction.
  • the convergent part 41 and the divergent part 43 do not need to have a configuration in which the flow path cross-sectional area changes smoothly (continuously) toward the downstream side, and the flow path cross-sectional area changes stepwise (Step by Step). It may be configured to.
  • the configuration of the fourth embodiment can be applied to the configurations of the first and second embodiments described above.
  • the divergent portion 43 downstream of the connection portion 71 b of the first passage 71 by providing the divergent portion 43 downstream of the connection portion 71 b of the first passage 71, the convergent-divergent nozzle 40 can be substantially formed.
  • the flow passage cross-sectional area changes not only in the branching portion 31 but also in the branching portion to the first passage 71, so that the convergence portion is connected to the exhaust passage 7 downstream of the first passage connecting portion 71b.
  • 41 and the throat portion 42 are formed.
  • the portion of the exhaust passage 7 between the connection portion 71 b and the divergent portion 43 becomes the throat portion 42.
  • FIG. 13 is a cross-sectional view for explaining the configuration of an engine exhaust device and the like according to the fifth embodiment of the present invention.
  • portions corresponding to the respective portions shown in FIG. 11 described above are denoted by the same reference numerals and description thereof is omitted.
  • one catalyst 23 is disposed downstream of the convergent-divergent nozzle 40 in the exhaust passage 7.
  • the downstream end 72 b of the second passage 72 is coupled to the side surface of the catalyst 23. That is, a cylindrical air introduction space 81 that opens almost the entire side surface of the catalyst 23 is formed at the downstream end 72 b of the second passage 72.
  • a large number of air introduction holes 82 for introducing air into the inside are formed on the side surface of the catalyst 23.
  • the secondary air that has entered the inside of the catalyst 23 travels toward the downstream end of the catalyst 23 while being mixed with the exhaust gas introduced from the upstream end 23 a of the catalyst 23.
  • the cone-shaped region 24A tapering from the upstream end 23a to the downstream of the catalyst 23 becomes a low oxygen concentration region where the exhaust from the combustion chamber 10 is dominant.
  • the catalyst 23 functions as a reduction catalyst in the low oxygen concentration region 24A, and functions as an oxidation catalyst in the high oxygen concentration region 24B.
  • one catalyst 23 can be used both as a reduction catalyst and an oxidation catalyst, exhaust from the combustion chamber 10 can be sufficiently detoxified. Therefore, exhaust purification efficiency can be increased. Further, since only one catalyst 23 is required, the heat capacity of the entire exhaust device 50 can be reduced. As a result, when the engine 1 is started, the catalyst 23 can be activated quickly, so that exhaust can be sufficiently purified immediately after the engine is started.
  • an orifice (throttle) 83 is arranged in the middle of the range from the connecting portion of the first passage 71 and the second passage 72 to the downstream end 71b of the first passage 71. is there. Thereby, the exhaust from the combustion chamber 10 can be prevented from entering the first passage 71 without affecting the supply of secondary air. Thereby, the oxygen concentration of the air supplied to the second passage 72 can be increased.
  • the orifice 83 may be a plate-like body having an opening at the center, for example.
  • FIG. 14 is a schematic perspective view for explaining a configuration example of the catalyst 23.
  • the catalyst 23 has a honeycomb-shaped metal carrier 85.
  • the metal carrier 85 is formed by alternately laminating perforated flat foil (foil material) 86 and perforated wave foil (foil material) 87 to form a honeycomb structure. More specifically, a belt-like flat foil 86 and a belt-like wave foil 87 are overlapped and wound into a roll shape, thereby forming a metal carrier 85 having a cylindrical honeycomb structure.
  • the flat foil 86 is formed by uniformly dispersing a large number of air holes 86a in a flat metal foil.
  • FIG. 15 is a cross-sectional view for explaining the configuration of an engine exhaust system and the like according to the sixth embodiment of the present invention.
  • portions corresponding to the respective portions shown in FIG. 13 are given the same reference numerals, and description thereof is omitted.
  • downstream end 72b of the second passage 72 is connected to the side surface of the catalyst 23 and the outer peripheral region of the upstream end 23a of the catalyst 23. That is, the downstream end 72b of the second passage 72 is formed with a cylindrical air introduction space 88 that opens almost the entire side surface of the catalyst 23 and opens the outer peripheral portion of the upstream end 23a of the catalyst 23.
  • the configuration of the catalyst 23 is as described above.
  • the secondary air supplied from the first passage 71 to the second passage 72 enters the inside of the catalyst 23 from the air introduction space 88. That is, it enters the inside of the catalyst 23 from the side surface of the catalyst 23 and the outer peripheral region of the upstream end 23 a of the catalyst 23.
  • the secondary air that has entered the inside of the catalyst 23 goes to the downstream end of the catalyst 23 while being mixed with the exhaust gas introduced from the central region of the upstream end 23 a of the catalyst 23.
  • the cone-shaped region 24A which tapers from the central region of the upstream end 23a of the catalyst 23 toward the downstream, becomes a low oxygen concentration region where the exhaust from the combustion chamber 10 is dominant.
  • the catalyst 23 functions as a reduction catalyst in the low oxygen concentration region 24A, and functions as an oxidation catalyst in the high oxygen concentration region 24B.
  • one catalyst 23 can be used both as a reduction catalyst and an oxidation catalyst. Since secondary air is also introduced from the outer peripheral region of the upstream end 23a of the catalyst 23, the low oxygen concentration region 24 is smaller than in the case of the fifth embodiment. That is, the high oxygen concentration region 25 is larger than in the case of the fifth embodiment. Therefore, since a sufficient amount of secondary air can be supplied to the catalyst 23, exhaust from the combustion chamber 10 can be sufficiently detoxified.
  • FIG. 16 is a schematic diagram showing a configuration of an engine exhaust device according to a seventh embodiment of the present invention.
  • the same reference numerals are assigned to the corresponding parts of the respective parts shown in FIG.
  • the fifth embodiment is an example in which one embodiment of the present invention is applied to a multi-cylinder engine.
  • the engine 1 of the seventh embodiment has a plurality of cylinders #A and #B.
  • Each cylinder #A, #B includes a cylinder body 3 (see FIG. 1), a cylinder head 4 provided at one end thereof, and a piston 5 (see FIG. 1) that reciprocates within the cylinder body 3.
  • a combustion chamber 10 is formed.
  • the cylinder head 4 includes an intake valve 8 (see FIG. 1) for opening and closing an intake port 8a (see FIG. 1), an exhaust valve 9 for opening and closing an exhaust port 9a, an intake valve 8 (see FIG. 1), and an exhaust valve 9 And a valve operating device for driving the motor.
  • the engine 1 further includes an exhaust device 50 and a secondary air supply device 70 that supplies air to the exhaust passage 7 of the exhaust device 50.
  • the exhaust device 50 includes a first exhaust pipe 51 connected to the cylinder head 4, a second exhaust pipe 52 connected to the first exhaust pipe 51, and a third exhaust pipe connected to the second exhaust pipe 52. 53. These exhaust pipes 51, 52, 53 form an exhaust passage 7 (7A, 7B, 7C).
  • the first exhaust pipe 51 forms individual exhaust passages 7A and 7B connected to the exhaust ports 9a of the plurality of combustion chambers 10, respectively. These individual exhaust passages 7A and 7B are gathered at the gathering portion 25 and connected to the gathered exhaust passage 7C.
  • a convergent-divergent nozzle 40 is provided in the collective exhaust passage 7C.
  • the first and second catalysts 21 and 22 are arranged at an interval in the collective exhaust passage 7C on the downstream side of the convergent-divergent nozzle 40.
  • a first secondary air supply pipe 76 that forms a first passage 71 is connected to the collective exhaust passage 7 ⁇ / b> C between the collective portion 25 and the convergent-divergent nozzle 40.
  • the first secondary air supply pipe 76 is connected to the upstream end of the second secondary air supply pipe 77 that forms the second passage 72.
  • the downstream end of the second secondary air supply pipe 77 is connected to the collective exhaust passage 7 ⁇ / b> C between the first and second catalysts 21, 22, that is, downstream of the first catalyst 21.
  • Other configurations are the same as those in the first embodiment.
  • FIGS. 17A to 17C are schematic views showing the operation of the engine according to the seventh embodiment.
  • the individual exhaust passage 7A of another cylinder #A in which the exhaust port 9a is closed functions as the branch portion 31. That is, when the exhaust port 9a of the cylinder #B is opened, the exhaust gas 36 is discharged from the exhaust port 9a, and a shock wave 35 is generated, which propagates through the individual exhaust passage 7B (see FIG. 17A).
  • the shock wave 35 branches at the collecting portion 25 and enters the individual exhaust passage 7A of the other cylinder #A.
  • the branched shock wave 35 propagates upstream in the individual exhaust passage 7A (see FIG.
  • the reflected shock wave 35 propagates through the individual exhaust passage 7A to the downstream side, reaches the collecting portion 25 again (see FIG. 17C), and collides with the exhaust gas 36. As a result, the pressure at the inlet of the convergent-divergent nozzle 40 is increased, and a new shock wave is generated in the divergent section 43.
  • the external secondary air is introduced into the first passage 71 by the negative pressure generated with the generation of this new shock wave.
  • the secondary air introduced into the first passage 71 is sent into the second passage 72.
  • the secondary air is sent into the collective exhaust passage 7 ⁇ / b> C downstream of the first catalyst 21.
  • the ignition order is cylinder # 1-cylinder # 3-cylinder # 4-cylinder # 2.
  • a set of the cylinder # 1 and the cylinder # 4 whose ignition timings are different by 360 degrees corresponds to the set of the two cylinders #A and #B.
  • a set of cylinder # 2 and cylinder # 3 having ignition timings different by 360 degrees corresponds to the set of the two cylinders #A and #B. That is, in the four-cylinder engine, there are two pairs of cylinders corresponding to the two cylinders #A and #B.
  • FIG. 18 is a perspective view showing an example of a ship equipped with an engine according to an embodiment of the present invention.
  • the ship 100 includes a hull 102 and an outboard motor 101 having the engine 1 according to an embodiment of the present invention.
  • the outboard motor 101 includes, for example, the engine 1, a propeller (not shown) as a propulsion force generating member, and a transmission mechanism (not shown) that transmits the driving force of the engine 1 to the propeller.
  • the transmission mechanism includes, for example, a drive shaft that is rotated by the driving force of the engine 1, a propeller shaft that is coupled to the propeller, and a clutch that is provided between the drive shaft and the propeller shaft.
  • FIG. 19 is a perspective view showing a vehicle equipped with an engine according to an embodiment of the present invention.
  • a motorcycle 200 as an example of a vehicle includes a vehicle body 201, front wheels 202 and rear wheels 203 (wheels) attached to the front and rear of the vehicle body 201, and the engine 1 according to an embodiment of the present invention. I have.
  • the engine 1 is disposed in the center of the vehicle body 201.
  • the driving force generated by the engine 1 is transmitted to the rear wheel 203 by the transmission mechanism 204.
  • FIG. 20 is a cross-sectional view of an exhaust passage and the like showing a modification of the embodiment.
  • the first secondary air supply pipe 76 that is, the first passage 71 is connected to the exhaust passage 7 downstream from the branch portion 31.
  • the connection position of the first passage 71 may be upstream from the branch portion 31 (see reference numeral 71A), or may be the same position as the branch section 31 (see reference numeral 71B).
  • an engine having one exhaust port provided for one combustion chamber is shown, but a plurality of exhaust ports may be provided for one combustion chamber.
  • a plurality of exhaust ports may be provided for one combustion chamber.
  • two or more nozzles may be provided for one combustion chamber. It goes without saying that these modifications can be applied to a multi-cylinder engine having a plurality of combustion chambers.
  • the present invention can be applied to a wide variety of engines.
  • this configuration substantially includes a plurality of branch portions. Will have.
  • the shock waves propagating through the branch portions collide with each other and are reflected.
  • a portion where a plurality of branch portions are connected becomes a reflection portion. The reflection portion is formed even if a member such as a wall is not necessarily present.
  • the second catalyst 22 may be omitted as in the modification of the first embodiment shown in FIG.
  • the upstream portion of the first catalyst 21 can act as a reduction catalyst, while the downstream portion can act as an oxidation catalyst. it can. That is, when the secondary air introduced from the second passage 72 is guided to the first catalyst 21 by the exhaust pulsation, the air ratio in the exhaust gas increases. Thereby, the downstream part of the 1st catalyst 21 functions as an oxidation catalyst. In this way, exhaust gas can be efficiently purified using secondary air. Similar modifications can be made in the second to fourth and sixth embodiments.
  • the air amount control valve 75 and the air cleaner are provided upstream of the reed valve 74 in the first passage 71, but one or both of them may be omitted.
  • the reed valve 74 is disposed at the upstream end of the first passage 71.
  • the reed valve 74 may be disposed between the upstream end and the downstream end of the first passage 71. Good.
  • the upstream end 72 a of the second passage 72 may be disposed between the reed valve 74 and the exhaust passage 7 in the first passage 71.
  • the catalyst shown in FIG. 14 can also be used as the first and / or second catalysts 21 and 22 in the embodiments other than the fifth and sixth embodiments.
  • the first and / or second catalysts 21 and 22 do not need to have a catalyst carrier having an air inlet on the side surface, and may be configured so that exhaust can be introduced from the upstream end.
  • the configuration in which the secondary air is supplied to the exhaust passage via the second passage 72 has been described, but the supply destination of the secondary air may be other than the exhaust passage.
  • the downstream end of the second passage 72 is coupled to the inlet 65 of the pressure accumulation tank 63.
  • the accumulator tank 63 defines a storage space 64 that can store high-pressure air having a pressure higher than atmospheric pressure.
  • the pressure accumulating tank 63 has an introduction port 65 through which air is introduced, a one-way valve 66 that opens and closes the introduction port 65, and a discharge port 67 through which high-pressure air in the accommodation space 64 is discharged.
  • the one-way valve 66 is configured to open when the air pressure in the second passage 72 is higher than the air pressure in the accommodation space 64 to allow air to flow from the second passage 72 into the accommodation space 64.
  • the one-way valve 66 is kept closed when the air pressure in the accommodation space 64 is equal to or higher than the air pressure in the second passage 72, thereby preventing the outflow of air from the accommodation space 64 to the second passage 72. It is configured.
  • the pressure can be accumulated. That is, the exhaust energy can be converted into pressure energy and accumulated.
  • An upstream end of a high-pressure air supply path 68 is connected to the discharge port 66.
  • An output control valve 69 is arranged in the middle of the high-pressure air supply path 68. By opening and closing the output control valve 69, the output of high-pressure air (compressed air) accumulated in the pressure accumulation tank 64 can be controlled.
  • the downstream end of the high-pressure air supply path 68 is connected to a device 210 that operates using high-pressure air.
  • An example of such a device 210 is an operation assisting device represented by a brake booster and a clutch booster.
  • Other examples of the device 210 include an air suspension device and a horn device.

Abstract

La présente invention a trait à un moteur qui inclut : un dispositif d'échappement qui est équipé d'une trajectoire d'échappement permettant de guider le gaz d'échappement évacué depuis la chambre de combustion ; et un dispositif d'alimentation en air permettant de fournir de l'air. La trajectoire d'échappement est pourvue d'une section convergente, d'une section divergente et d'une section de dérivation. La section de dérivation dérive, en amont de la section divergente, une onde de choc de la trajectoire d'échappement, l'onde de choc se propageant dans la trajectoire d'échappement jusqu'en aval, et la section de dérivation propage l'onde de choc de nouveau vers la trajectoire d'échappement. Le dispositif d'alimentation en air inclut : une première trajectoire qui est pourvue d'une première soupape à clapets permettant à un écoulement de gaz de circuler à travers celle-ci, ledit écoulement de gaz circulant de l'extrémité en amont vers l'extrémité en aval, et qui est dotée d'une extrémité en aval connectée à une partie de la trajectoire d'échappement, ladite partie étant située en amont de la section divergente ; et une seconde trajectoire qui est pourvue d'une extrémité en amont connectée à une partie de la première trajectoire, ladite partie étant située en aval de la première soupape à clapets. Le dispositif d'échappement est configuré de manière à ce que le gaz d'échappement passe par la section convergente et entre en collision, entre la section de dérivation et la section divergente, avec l'onde de choc qui s'est propagée à travers la section de dérivation.
PCT/JP2010/071488 2009-12-11 2010-12-01 Moteur, véhicule et bateau comprenant ledit moteur WO2011070955A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
BR112012012777A BR112012012777A2 (pt) 2009-12-11 2010-12-01 motor, e veículo e embarcação que compreendem o mesmo
CN201080056390.4A CN102686844B (zh) 2009-12-11 2010-12-01 发动机及包括该发动机的车辆和船舶
EP10835876.3A EP2511494A4 (fr) 2009-12-11 2010-12-01 Moteur, véhicule et bateau comprenant ledit moteur

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2009281823 2009-12-11
JP2009-281823 2009-12-11

Publications (1)

Publication Number Publication Date
WO2011070955A1 true WO2011070955A1 (fr) 2011-06-16

Family

ID=44145500

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2010/071488 WO2011070955A1 (fr) 2009-12-11 2010-12-01 Moteur, véhicule et bateau comprenant ledit moteur

Country Status (4)

Country Link
EP (1) EP2511494A4 (fr)
CN (1) CN102686844B (fr)
BR (1) BR112012012777A2 (fr)
WO (1) WO2011070955A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2017227173A (ja) * 2016-06-22 2017-12-28 義明 角田 排気ガス流の加速装置
CN114797374A (zh) * 2022-05-31 2022-07-29 山东天景工程设计有限公司 一种煤焦油装车过程异味治理装置
CN114797374B (zh) * 2022-05-31 2024-04-26 山东天景工程设计有限公司 一种煤焦油装车过程异味治理装置

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102017203267A1 (de) * 2017-03-01 2018-09-06 Bayerische Motoren Werke Aktiengesellschaft Brennkraftmaschine mit einer Abgasanlage
IT201700124022A1 (it) * 2017-10-31 2019-05-01 Piaggio & C Spa Sistema di scarico per motore due tempi e relativo veicolo a motore
DE102022111152B3 (de) * 2022-05-05 2023-07-06 Tenneco Gmbh Abgaskühlvorrichtung

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61155620A (ja) * 1984-12-21 1986-07-15 アウトボ−ド・マ−リン・コ−ポレ−シヨン エンジン装置
JP2004150310A (ja) * 2002-10-29 2004-05-27 Honda Motor Co Ltd 内燃機関の排気装置
JP2006220019A (ja) 2005-02-08 2006-08-24 Yamaha Motor Co Ltd エンジンの排ガス浄化装置
JP2008031868A (ja) * 2006-07-26 2008-02-14 Yamaha Marine Co Ltd ８気筒エンジンにおける排気装置
JP2009281823A (ja) 2008-05-21 2009-12-03 Yanmar Co Ltd 青果物品質判定装置
WO2009151135A1 (fr) * 2008-06-13 2009-12-17 ヤマハ発動機株式会社 Moteur, véhicule, embarcation et procédé d’échappement du moteur

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6032340Y2 (ja) * 1980-03-24 1985-09-27 本田技研工業株式会社 自動二輪車用二気筒内燃機関の排気浄化装置
JPS58106119A (ja) * 1981-12-17 1983-06-24 Honda Motor Co Ltd 内燃機関における排気浄化装置
SE9903403L (sv) * 1999-09-22 2001-03-23 Electrolux Ab Tvåtakts förbränningsmotor
GB0103522D0 (en) * 2001-02-13 2001-03-28 Ricardo Consulting Eng Reciprocating Engines
JP2009024670A (ja) * 2007-07-23 2009-02-05 Yamaha Motor Co Ltd エンジン、自動二輪車用エンジン

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61155620A (ja) * 1984-12-21 1986-07-15 アウトボ−ド・マ−リン・コ−ポレ−シヨン エンジン装置
JP2004150310A (ja) * 2002-10-29 2004-05-27 Honda Motor Co Ltd 内燃機関の排気装置
JP2006220019A (ja) 2005-02-08 2006-08-24 Yamaha Motor Co Ltd エンジンの排ガス浄化装置
JP2008031868A (ja) * 2006-07-26 2008-02-14 Yamaha Marine Co Ltd ８気筒エンジンにおける排気装置
JP2009281823A (ja) 2008-05-21 2009-12-03 Yanmar Co Ltd 青果物品質判定装置
WO2009151135A1 (fr) * 2008-06-13 2009-12-17 ヤマハ発動機株式会社 Moteur, véhicule, embarcation et procédé d’échappement du moteur

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP2511494A4 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2017227173A (ja) * 2016-06-22 2017-12-28 義明 角田 排気ガス流の加速装置
CN114797374A (zh) * 2022-05-31 2022-07-29 山东天景工程设计有限公司 一种煤焦油装车过程异味治理装置
CN114797374B (zh) * 2022-05-31 2024-04-26 山东天景工程设计有限公司 一种煤焦油装车过程异味治理装置

Also Published As

Publication number Publication date
EP2511494A1 (fr) 2012-10-17
CN102686844A (zh) 2012-09-19
CN102686844B (zh) 2014-08-27
BR112012012777A2 (pt) 2016-08-16
EP2511494A4 (fr) 2015-03-04

Similar Documents

Publication Publication Date Title
JP5214728B2 (ja) エンジン、車両、および船舶
US8142247B2 (en) Exhaust device for outboard motor engine and outboard motor
JP4880071B2 (ja) エンジン、車両、船舶、およびエンジンの排気方法
CN1249331C (zh) 往复式发动机
WO2011070955A1 (fr) Moteur, véhicule et bateau comprenant ledit moteur
TWI444534B (zh) Engine, and with its vehicles and ships

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 201080056390.4

Country of ref document: CN

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 10835876

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 1062/KOLNP/2012

Country of ref document: IN

WWE Wipo information: entry into national phase

Ref document number: 2010835876

Country of ref document: EP

NENP Non-entry into the national phase

Ref country code: DE

REG Reference to national code

Ref country code: BR

Ref legal event code: B01A

Ref document number: 112012012777

Country of ref document: BR

NENP Non-entry into the national phase

Ref country code: JP

ENP Entry into the national phase

Ref document number: 112012012777

Country of ref document: BR

Kind code of ref document: A2

Effective date: 20120528