Title:
PRE-CHAMBER COMBUSTION FOUR-STROKE ENGINE
Document Type and Number:
WIPO Patent Application WO/2023/157088
Kind Code:
A1
Abstract:
A pre-chamber combustion four-stroke engine (1) does not comprise an ignition assistance device that assists in ignition of a gaseous mixture, but does comprise a pre-chamber (20) that is in communication with a main combustion chamber (2) via a plurality of communication holes (21), and that is configured so that a portion of a pre-chamber spark plug (23) is exposed to an internal space of the pre-chamber. A control device (70) controls an intake passage injection valve (8) that injects a fuel into an intake passage (5) so that, in at least a part of a low-load region, a gaseous mixture will have a first air–fuel ratio that allows treatment with a three-way catalyst after combustion or a second air–fuel ratio that is richer than the first air–fuel ratio. A cylinder head (10) comprises a cooling section (16) that accommodates a cooling medium that receives heat from an electrode section (24) of the pre-chamber spark plug and a pre-chamber wall section (22) in which the plurality of communication holes are formed. The following are each formed so as to be dispersed in a circumferential direction: a plurality of spark discharges (33) produced by the electrode section of the pre-chamber spark plug; the plurality of communication holes; a plurality of heat paths (14) from the electrode section of the pre-chamber spark plug to the cooling section; and a plurality of heat paths (15) from the pre-chamber wall section to the cooling section.
Inventors:
EGASHIRA SHUICHI (JP)
Application Number:
PCT/JP2022/005988
Publication Date:
August 24, 2023
Filing Date:
February 15, 2022
Export Citation:
Assignee:
YAMAHA MOTOR CO LTD (JP)
International Classes:
F02B17/00; F01P3/02; F02B19/08; F02F1/36; H01T13/46
Domestic Patent References:
| WO2004040130A1 | 2004-05-13 |
Foreign References:
| US20070119409A1 | 2007-05-31 | |||
| JP2016014340A | 2016-01-28 | |||
| JP2018112122A | 2018-07-19 | |||
| JPH0714595U | 1995-03-10 | |||
| US20170167357A1 | 2017-06-15 | |||
| JP2004165168A | 2004-06-10 | |||
| JP2005299679A | 2005-10-27 |
Attorney, Agent or Firm:
ATEN IP ATTORNEYS (JP)
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