Exhaust device of multi-cylinder engine

• US 10,233,832 B2
• Filed: 08/13/2015
• Issued: 03/19/2019
• Est. Priority Date: 09/01/2014
• Status: Active Grant

• Current Assignee: Mazda Motor Corporation
• Original Assignee: Mazda Motor Corporation
• Inventors: Shimoji, Hiroki, Hoshino, Tsukasa, Yamamoto, Ryo, Yanagida, Haruna, Endo, Koji
• Primary Examiner(s): Dounis, Laert
• Assistant Examiner(s): Largi, Matthew T
• Application Number:
  US14/825,576
• Publication Number:
  US 20160061089A1
• Time in Patent Office: 1,314 Days
• CPC Class Codes: F01N 13/008 Mounting or arrangement of exhaust sensors in or on exhaust apparatus sensor arrangements for engine control F02D41/1439
• CPC Class Codes: F01N 13/107 More than one exhaust manifold or exhaust collector
• CPC Class Codes: F01N 13/1805 Fixing exhaust manifolds, exhaust pipes or pipe sections to each other, to engine or to vehicle body pipe joints in general F16L; fixing auxiliaries in motor vehicles in general B60K
• CPC Class Codes: F01N 2340/00 Dimensional characteristics of the exhaust system, e.g. length, diameter or volume of the apparatus; Spatial arrangements of exhaust apparatuses
• CPC Class Codes: F01N 2340/02 characterised by the distance of the apparatus to the engine, or the distance between two exhaust treating apparatuses
• CPC Class Codes: F01N 2340/04 characterised by the arrangement of an exhaust pipe, manifold or apparatus in relation to vehicle frame or particular vehicle parts
• CPC Class Codes: F01N 2470/10 Tubes having non-circular cross section
• CPC Class Codes: F01N 2470/20 Dimensional characteristics of tubes, e.g. length, diameter
• CPC Class Codes: F01N 2560/025 for measuring or detecting O2, e.g. lambda sensors
• CPC Class Codes: F01N 3/101 Three-way catalysts
• CPC Class Codes: F02B 75/18 Multi-cylinder engines scavenging aspects F02B25/00
• CPC Class Codes: F02B 77/086 Sensor arrangements in the exhaust, e.g. for temperature, misfire, air/fuel ratio, oxygen sensors
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

An exhaust purification device of a multi-cylinder engine which improves exhaust gas purification performance by substantially uniforming a flow rate of exhaust gas throughout a treatment carrier such as a catalyst and improving dispersibility of the exhaust gas from the multi-cylinder engine to the catalyst and other components in the exhaust purification device wherein two collecting pipes are arranged at substantially symmetric positions across a partition plate part, which has a linear cross sectional shape, and is arranged centrally between the pipes which are each formed into D-shaped cross sectional shapes and comprise a first straight line part, a pair of second straight line parts connected with respective ends of a first straight line part and arranged to be substantially parallel with each other, and a circular arc part that connects ends of a pair of second straight line parts on opposite sides of the first straight line part.

Claims

1. An exhaust device of a multi-cylinder engine that connects two collecting pipes communicating with two cylinders respectively with an exhaust purification device through a taper, comprising:

a D-shaped cross sectional shape formed respectively by downstream ends of the two collecting pipes and arranged at substantially symmetric positions across a partition part that has a linear cross sectional shape and is arranged at a central part between the two collecting pipes,

wherein the D-shaped cross sectional shape includes a first straight line part, a pair of second straight line parts that are connected with each end of the first straight line part respectively and are arranged to be substantially parallel to each other, and an arc part that connects ends of the pair of second straight line parts on opposite sides of the first straight line part to each other;

wherein the exhaust purification device is arranged so that an inclination of the exhaust purification device is different from inclinations of the collecting pipes;

wherein a recessed part is formed at a vehicle front side of the taper so as to intersect an extending line that is parallel to the partition part and extends in a direction transverse to an exhaust flow direction of the two collecting pipes at the partition part, such that an exterior wall of the recessed part is recessed inwardly into the taper, and exhaust gas is directed toward a center of the exhaust purification device by the recessed part; and

wherein ends of the two collecting pipes extend diagonally downward in a downstream direction toward a vehicle rear side, the exhaust purification device extends diagonally downward toward the vehicle rear side and is arranged so that the inclination thereof is more horizontal than inclinations of the ends of the two collecting pipes, and the recessed part recessed inwardly into the taper is formed as a sensor mounting part for mounting an exhaust sensor on ends of the taper on the vehicle front side.

2. The exhaust device of the multi-cylinder engine according to claim 1, wherein the following formulas (1) and (2) are satisfied by defining a length of the first straight line part as A, a length of the second straight line parts as B, and a distance between the first straight line part and an end of the arc part on a convex side as C:

A/B=4 to 5 

 

(1)

C/A=0.7 to 0.8 

 

(2).

3. An exhaust device of a multi-cylinder engine that divides a plurality of cylinders to two sets of cylinder groups formed by the plurality of cylinders, comprising:

branch pipes which communicate with cylinders of the cylinder groups for each of the two sets of cylinder groups;

two collecting pipes configured by collecting the branch pipes to be connected with an exhaust purification device through a taper; and

a D-shaped cross sectional shape formed by the two collecting pipes respectively being arranged at substantially symmetric positions across a partition part that has a linear cross sectional shape and is arranged at a central part between the two collecting pipes,

wherein the D-shaped cross sectional shape includes a first straight line part, a pair of second straight line parts that are connected with each end of the first straight line part respectively and are arranged to be substantially parallel each other, and an arc part that connects ends of the pair of second straight line parts on the opposite sides of the first straight line part to each other;

wherein the partition part, provided between the two collecting pipes, has a component that extends in a cylinder line direction across the cylinders of the engine;

wherein the two collecting pipes and the exhaust purification device extend in a diagonally downward direction including a component in the cylinder line direction toward a vehicle rear side, so that gas flow passages within a case of the exhaust purification device extend diagonally downward toward the vehicle rear side;

wherein a recessed part is formed so as to intersect an extending line that is parallel to the partition part and extends in a direction transverse to an exhaust flow direction of the two collecting pipes at the partition part, such that an exterior wall of the recessed part is inwardly recessed into the taper at an upward end, in the cylinder line direction, of the taper; and

wherein an inclination of the exhaust purification device is arranged to be more horizontal than inclinations of the two collecting pipes.