摘要:
An expansion chamber, and first and second volume chambers on either side of said expansion chamber, are formed inside a muffler housing. Engine exhaust is led by an inlet tube to the first volume chamber, and an opening facing the expansion chamber is formed in an intermediate part of the inlet tube. Exhaust in the second volume chamber is discharged outside by a tail tube, and an opening is formed facing the expansion chamber in an intermediate part of the tail tube. A valve is provided for leading exhaust from the first volume chamber to the second volume chamber according to a pressure difference between the chambers. This forms two exhaust flowpaths. A resonance system with two degrees of freedom is thereby formed with respect to exhaust discharged via the two openings and the expansion chamber, and a high noise silencing efficiency is obtained.
摘要:
An exhaust sound controlling method including reducing a flow rate of exhaust gas that passes through an exhaust path, to a first flow rate in accordance with increase in engine speed in a first engine speed region, and increasing the flow rate of exhaust gas to a second flow rate in accordance with increase in engine speed in a second engine speed region higher in engine speed than the first engine speed region. An exhaust sound controlling apparatus including a baffle plate and a valve that is operated to open a communication passage that communicates upstream and downstream sides of the baffle plate in an engine starting region, close the communication passage in an idling region and a low engine speed region, and open the communication passage and increase an opening of the valve as the engine speed rises in a high engine speed region.
摘要:
A first and second noise suppressing mechanism are provided inside the muffler. Each mechanism is provided with a discharge pipe for discharging exhaust gas to outside the muffler. The first noise suppressing mechanism reduces exhaust noise in the low engine speed region. The second noise suppressing mechanism reduces noise in the medium and high engine speed regions. A valve is provided that connects the first noise suppressing mechanism and second noise suppressing mechanism according to the engine exhaust pressure. In the low speed region, the valve is closed and exhaust gas is discharged via the first noise suppressing mechanism where mainly low frequency noise is eliminated. In the medium and high speed regions, the valve is opened and exhaust gas is also discharged via the second noise suppressing mechanism where high frequency noise specific in these regions is also eliminated. Further, by the increased exhaust cross-sectional area, power drop due to increase of back pressure in the muffler in the high speed region, is prevented.
摘要:
A plurality of chambers are partitioned in a muffler by a baffle board. The muffler is provided with an exhaust gas passage for discharging exhaust gas outside the muffler via these chambers and a valve that bypasses a part of the exhaust passage. This valve opens according to the exhaust gas pressure. Also provided are a mechanism for pushing the valve in a closing direction, and a mechanism for damping the shock when the valve closes. Thus, valve closing noise is suppressed, and exhaust gas noise is further suppressed.
摘要:
The inner area of a muffler of an engine is partitioned into an expansion chamber, a first volume chamber and a second volume chamber. An inlet tube and the first volume chamber are connected by a first passage. The first volume chamber and a second volume chamber are connected by a second passage, and the second volume chamber and expansion chamber are connected by a third passage. The flow of exhaust gas reaching the expansion chamber via the first passage, second passage and third passage is blocked by a valve which opens according to a pressure rise of the exhaust gas. One of the two acoustic paths formed when the valve is open functions as a resonator having two degrees of freedom relative to the other path so that a high muffling effect is obtained.
摘要:
An inlet tube leads exhaust gas from an automobile engine to an expansion chamber inside a muffler housing. Exhaust gas from the expansion chamber is discharged to the atmosphere via a first tail tube. A dead space chamber and volume chamber are disposed on either side of the expansion chamber in the housing, and a first internal tube connects the volume chamber and expansion chamber. A second internal tube having a valve which opens under pressure of the exhaust gas connects the volume chamber and dead space chamber. Exhaust gas from the dead space chamber is discharged to the atmosphere via a second tail tube. As the dead space chamber and volume chamber are not adjacent, pressure waves in the volume chamber do not cause a volume change of the dead space chamber, and emission noise from the second tail tube due to excitation of a resonance system comprising the dead space chamber, is reduced.
摘要:
A first and second noise suppressing mechanism are provided inside the muffler. Each mechanism is provided with a discharge pipe for discharging exhaust gas to outside the muffler. The first noise suppressing mechanism reduces exhaust noise in the low engine speed region. The second noise suppressing mechanism reduces noise in the medium and high engine speed regions. A valve is provided that connects the first noise suppressing mechanism and second noise suppressing mechanism according to the engine exhaust pressure. In the low speed region, the valve is closed and exhaust gas is discharged via the first noise suppressing mechanism where mainly low frequency noise is eliminated. In the medium and high speed regions, the valve is opened and exhaust gas is also discharged via the second noise suppressing mechanism where high frequency noise specific in these regions is also eliminated. Further, by the increased exhaust cross-sectional area, power drop due to increase of back pressure in the muffler in the high speed region, is prevented.
摘要:
There is provided a novel pest control agent, particularly an insecticide or miticide. A substituted isoxazoline compound of General Formula (1): where A1, A2 and A3 independently are CH or N, etc., X1, X2 and X3 are independently are H, a halogen atom, etc., Y1 is H, etc., R1 is —C(O)R1a, —C(S)R1a, R1a is —C(R9)(R9a)—S(O)rR10, —C(R9)(R9a)—S(O)t(R10)═NR11, etc., R2 is H, etc., R3 is CF3, CClF2, etc., R4 is H, etc., R9 is H, etc., R9a is H, etc., R10 is C1-2 alkyl, etc., R11 is H, etc., r is an integer of 0-2, t is an integer of 0 or 1; and a pest control agent comprising the compound or the salt thereof.
摘要:
There is provided a novel pesticide, particularly an insecticide or an acaricide. A substituted isoxazoline compound of formula (1) or a salt thereof: wherein A1, A2 and A3 independently of one another are carbon atom or nitrogen atom, G is benzene ring, etc., L is —CH2—, —C(CH3)—, —CH(CN)—, etc., X is halogen atom, C1-C6haloalkyl, etc., Y is halogen atom, C1-C6alkyl, etc., R1 is —C(O)R1a, —C(O)OR1a, —C(O)NHR1a, etc., R2 is hydrogen atom, C1-C6haloalkyl, —C1-C4alkoxy C1-C4alkyl, cyano C1-C6alkyl, C3-C6alkenyl, C3-C6alkynyl, —C(O)R15, —C(O)OR15, etc., R3 is C1-C6haloalkyl, etc., m is an integer of 0 to 5, n is an integer of 0 to 4. The pesticide containing these compounds.
摘要:
There is provided a novel pest control agent, particularly an insecticide or miticide. A substituted isoxazoline compound of General Formula (1): where A1, A2 and A3 independently are CH or N, etc., X1, X2 and X3 are independently are H, a halogen atom, etc., Y1 is H, etc., R1 is —C(O)R1a, —C(S)R1a, R1a is —C(R9)(R9a)—S(O)rR10, —C(R9)(R9a)—S(O)t(R10)═NR11, etc., R2 is H, etc., R3 is CF3, CClF2, etc., R4 is H, etc., R9 is H, etc., R9a is H, etc., R10 is C1-2 alkyl, etc., R11 is H, etc., r is an integer of 0-2, t is an integer of 0 or 1; and a pest control agent comprising the compound or the salt thereof.