RU2383749C1 - Ice multi-chamber exhaust silencer - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: invention relates to automotive engines, particularly to ICE multi-chamber exhaust silencers. Proposed silencer comprises casing (2) and gas flow passages. Face walls of casing (2) have intake (1) and exhaust (11) holes. Gas flow passages represent a set of movable enclosed chambers. The latter are formed by chambers 4 entering casing (3) of a pair of gear wheels. Chambers (4) are formed in recesses of teeth in gears (9). Gas stays immobile in said enclosed chambers relative to bottom (5) and sidewalls of chambers (4).

EFFECT: improved noise absorption and reduced aero hydrodynamic drag of silencer.

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Description

The invention relates to mechanical engineering, in particular to multi-chamber silencers of the exhaust noise of an internal combustion engine (ICE).

Known exhaust silencers for internal combustion engines with effective noise suppression (AS USSR No. 641140, publ. 05.01.79, 1245726, publ. 07/23/86, 1043329, publ. 09/23/83, 1019082, publ. 23.05. 83 g., 1010306, publ. 07.04.83 g.), Where the sound energy is dissipated due to frictional losses and changes in the direction of the gas stream. Also known patent US No. 5723041, publ. 03.03.98, patent EP No. 0894523, publ. 02.03.99, where the gas flow is divided by the impeller blades into flow elements and mixed by the movable and fixed impeller blades.

Also known patent RU No. 2323293, publ. 04/20/08, “A method for distributing gas in a silencer-catalyst system of an internal combustion engine and a gas distribution device for use in it.” The device contains a number of curved blades oriented in a certain way and motionless with respect to the body. The gas stream in the channel is isolated along the lateral perimeters and is continuous along the length of the stream. The cross-sectional area of the holes carries the functions of the conductivity of gases and sound with simultaneous sound absorption due to changes in motion and frictional loss of sound energy. The disadvantage of this design is the continuity of the gas flow and the energy loss of the conductivity of gas and sound from chamber to chamber when the direction of movement and friction of the gas against the walls of the motion chambers and openings change. In a continuous flow, the perturbation of the oscillation is transmitted along the flow. This makes it difficult to reduce sound when moving through the silencer chambers.

The technical result achieved during the implementation of this invention is the intensification of the impact on gas flows and noise factors, the implementation of modern requirements of more stringent standards for external and internal noise of the vehicle, the reduction of the aero-hydrodynamic resistance of the muffler and, as a result, the increase in cylinder filling and increase in power and torque on the crankshaft.

The specified technical result is achieved in that the gas flow channels are made by a combination of movable closed chambers, while the gas in the chambers is stationary relative to the bottom and side walls of the chambers. Moreover, the gas stream is divided into separate closed small volumes that are motionless relative to the walls of the chambers, isolated from the general flow and moving together with the walls of the chambers to the outlet through two sets of channels towards each other in the mixing cavity. The dimensions of the chambers and surface profiles ensure the operation of the silencer without resonance. At the same time, in the mixing cavity of the gas flows, the output resistance is excluded and there is an additional suppression of noise due to oncoming traffic. The insulated volume of gas in the moving chamber is protected by a relatively motionless wall from the excitation of oscillations by the gas stream. Comparative analysis with the prototype shows that the claimed silencer is distinguished by the separation of the gas stream into a single moving chamber, isolated from oscillations of the main stream, intensifying mixing and calming the flows at the exit.

The invention is illustrated by a drawing of a longitudinal section of a noise muffler.

The multi-chamber silencer of the exhaust gas from an internal combustion engine contains an inlet 1, a silencer housing 2, a housing 3 pairs of gears of a chamber 4 of a small closed volume gas, a chamber bottom 5, a side wall front 6, a side wall rear 7, an axis of rotation 8 of a plurality of chambers, gears 9 of a combination chambers, mixing cavity 10, outlet 11. Alternatively, a plurality of chambers may represent a depression of gear wheels.

The device operates as follows. When the gas stream enters the inlet 1 of the muffler housing 2, it is distributed over the outer chambers 4 in the cavity of the gear tooth 9. The excess area of the front side wall 6 (since the inner walls of the gear tooth overlap the surfaces of one tooth) allows the gears 9 to rotate on axes 8 When the camera 4 enters the housing 3, the pairs of gears form closed chambers in cross section by the surface of the bottom 5, front 6 and rear 7 of the side walls. At the end of the gear, they fit snugly against the covers (not shown in the drawing) of the housing 3. In the formed chamber, the gas flow is stationary relative to the bottom 5 and the walls 6 and 7 and moves with them. During further movement, closed volumes open when the gear 9 exits the housing 3 and counter flows are mixed in the cavity 10 and additionally quench the noise energy. The unit volume in the chamber is protected by a tooth from excitation of oscillations of the main gas flow, and during the movement of the chamber, the oscillations of the unit gas volume are damped.

Replacing the fixed chambers of existing silencer designs with moving ones allows you to apply a new technological principle for damping vibrations. In this case, the resistance at the inlet of the muffler is reduced by replacing the sliding friction of the gas stream with rolling friction on the axes 8 and dynamic losses when changing the direction of movement of the gas stream. To increase the efficiency of noise suppression and reduce resonance, it is possible to install successively similar gear pairs with other parameters of the cameras 4 (tooth profile).

The total volume of single chambers is sufficient for a given volume of gas flow. Corrosion resistance of the muffler is increased due to the sequence of changing the contact surface with the gas stream during rotation of the gears.

Reducing the aerodynamic drag of the silencer reduces the energy loss due to damping noise, and improves the performance of internal combustion engines.

Claims (1)

A multi-chamber silencer of an internal combustion engine, comprising a housing with end walls, in which inlet and outlet openings, gas flow channels are formed, characterized in that the gas flow channels are made by a combination of movable closed chambers, while the gas in the chambers is stationary relative to the bottom and side walls of the chambers .