EXHAUST SYSTEM FOR VARIABLE CYLINDER ENGINE

• US 20130255237A1
• Filed: 12/19/2012
• Published: 10/03/2013
• Est. Priority Date: 03/28/2012
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: MAEHARA, Hayato, YAMAGUCHI, Shigehiro, GOGAMI, Norihiko
• Granted Patent: US 8,973,354 B2
• Time in Patent Office: Days
• US Class Current: 60/299
• CPC Class Codes: F01N 13/009 having two or more separate purifying devices arranged in series
• CPC Class Codes: F01N 13/107 More than one exhaust manifold or exhaust collector
• CPC Class Codes: F01N 2590/04 for motorcycles
• CPC Class Codes: F01N 3/10 by thermal or catalytic conversion of noxious components of exhaust by using other chemical processes, chemical aspects of catalytic conversion, e.g. using specified catalysts, B01D53/34
• CPC Class Codes: F01N 3/28 Construction of catalytic reactors
• CPC Class Codes: F01N 3/34 using air conduits or jet air pumps, e.g. near the engine exhaust port
• CPC Class Codes: F02D 17/02 Cutting-out cutting-out engines in multiple engine arrangements F02D25/04
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

An exhaust system for a variable cylinder engine for assuring purification of exhaust gas without increasing the number of catalysts and an intake system for purifying blow-by gas. The exhaust system includes an activation side exhaust pipe connected to an activation cylinder group that operates normally. A deactivation side exhaust pipe is connected to a deactivation cylinder group wherein fuel supply is stopped under a particular condition. A gathering section is connected to downstream ends of the activation side exhaust pipe and the deactivation side exhaust pipe with a sub-catalyst disposed in the activation side exhaust pipe and a main catalyst disposed at the gathering section. The main catalyst is formed wherein gas passing therethrough is partitioned into flows independent of each other in a flow path direction. The activation side exhaust pipe and the deactivation side exhaust pipe are connected in a mutually independent state to the main catalyst.

Claims

1. An exhaust system for a variable cylinder engine comprising:

a variable cylinder engine having an activation cylinder group operating normally and a deactivation cylinder group wherein a fuel supply is stopped under a particular condition;

an activation side exhaust pipe connected to the activation cylinder group;

a deactivation side exhaust pipe connected to the deactivation cylinder group;

a gathering section connected to downstream ends of the activation side exhaust pipe and the deactivation side exhaust pipe;

a sub-catalyst disposed in the activation side exhaust pipe; and

a main catalyst disposed at the gathering section, wherein;

the main catalyst is formed such that gas passing therethough is partitioned into flows independent of each other in a flow path direction; and

the activation side exhaust pipe and the deactivation side exhaust pipe are connected in a mutually independent state to the main catalyst.

2. The exhaust system for a variable cylinder engine according to claim 1, wherein the main catalyst is formed in a flattened cross sectional shape to span in an array direction of the downstream ends of the activation side exhaust pipe and the deactivation side exhaust pipe.

3. The exhaust system for a variable cylinder engine according to claim 1, wherein the downstream end of at least one of the activation side exhaust pipe and the deactivation side exhaust pipe is abutted with an upstream end of the main catalyst.

4. The exhaust system for a variable cylinder engine according to claim 2, wherein the downstream end of at least one of the activation side exhaust pipe and the deactivation side exhaust pipe is abutted with an upstream end of the main catalyst.

5. The exhaust system for a variable cylinder engine according to claim 1, wherein:

the sub-catalyst includes an external cylinder in member configuring a shell thereof; and

a downstream end of the external cylinder member abuts with an upstream end of the main catalyst.

6. The exhaust system for a variable cylinder engine according to claim 2, wherein:

the sub-catalyst includes an external cylinder member configuring a shell thereof; and

a downstream end of the external cylinder member abuts with an upstream end of the main catalyst.

7. The exhaust system for a variable cylinder engine according to claim 1, wherein:

a partition wall partitions the portion at which the activation side exhaust pipe is connected and the portion at which the deactivation side exhaust pipe is connected from each other, said partition wall being provided at the gathering section; and

a downstream end of the partition wall abuts with an upstream end of the main catalyst.

8. The exhaust system for a variable cylinder engine according to claim 2, wherein:

a partition wall partitions the portion at which the activation side exhaust pipe is connected and the portion at which the deactivation side exhaust pipe is connected from each other, said partition wall being provided at the gathering section; and

a downstream end of the partition wall abuts with an upstream end of the main catalyst.

9. The exhaust system for a variable cylinder engine according to claim 1, wherein:

the activation side exhaust pipe includes a plurality of upstream side exhaust pipes connected to the cylinders of the activation cylinder group and an activation side gathering section connected to a downstream end of the upstream side exhaust pipes; and

the sub-catalyst is disposed at the activation side gathering section.

10. The exhaust system for a variable cylinder engine according to claim 9, wherein the activation side gathering section is configured as a separate member from the upstream side exhaust pipes.

11. The exhaust system for a variable cylinder engine according to claim 2, wherein:

the engine has a front cylinder block and a rear cylinder block disposed in a V-shape;

the activation cylinder group is incorporated in the cylinder block; and

the gathering section is disposed below the variable cylinder engine.

12. The exhaust system for a variable cylinder engine according to claim 3, wherein:

the engine has a front cylinder block and a rear cylinder block disposed in a V-shape;

the activation cylinder group is incorporated in the cylinder block; and

the gathering section is disposed below the variable cylinder engine.

13. An intake system for a variable cylinder engine comprising:

a variable cylinder engine having an activation cylinder group activated normally and a deactivation cylinder group wherein fuel supply is stopped under a particular condition; and

throttle bodies connected to the activation cylinder group and the deactivation cylinder group, respectively, and having an intake passage, the intake system comprising;

an upstream side intake passage provided on the upstream side of the throttle bodies and having a single chamber, wherein;

a partition wall for partitioning the chamber into a space on the activation cylinder group side and a space on the deactivation cylinder group side is provided in the upstream side intake passage; and

a blow-by gas returning pipe connects an internal space of the variable cylinder engine and the space on the activation cylinder group side to each other.

14. The intake system for a variable cylinder engine according to claim 13, wherein:

the upstream side intake passage is an air cleaner having the single chamber;

the partition wall for partitioning the chamber into the space on the activation cylinder group side and the space on the deactivation cylinder group is provided in the air cleaner; and

the blow-by gas returning pipe connects an internal space of the variable cylinder engine and a space on the activation cylinder group side to each other.

15. The intake system for a variable cylinder engine according to claim 14, wherein:

the partition wall extends from a bottom portion of a clean chamber of the air cleaner toward an element; and

the blow-by gas returning pipe is connected to the space of the activation cylinder group side of the clean chamber.

16. The intake system for a variable cylinder engine according to claim 15, wherein an inlet of the blow-by gas returning pipe is provided and directed to the partition wall.

17. The intake system for a variable cylinder engine according to claim 13, wherein the blow-by gas returning pipe is connected at the upstream end thereof to a front cylinder block of the activation cylinder group side.

18. The intake system for a variable cylinder engine according to claim 17, wherein:

the air cleaner is disposed directly above the front cylinder block;

the blow-by gas returning pipe is connected at the upstream end thereof to a cylinder head cover of the activation cylinder group side; and

the blow-by gas returning pipe is connected at the downstream end thereof to the space on the activation cylinder group side of the air cleaner.

19. The intake system for a variable cylinder engine according to claim 14, wherein

the variable cylinder engine includes a secondary air supplying apparatus for introducing fresh air into exhaust passages;

and

an air intake opening of the secondary air supplying apparatus is provided for the space on the deactivation cylinder group side of the air cleaner.

20. The intake system for a variable cylinder engine according to claim 19, wherein the inlet of the blow-by gas returning pipe and the air intake opening of the secondary air supplying apparatus are provided on or in the proximity of the bottom portion of the air cleaner.