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Automobile industry

Diesel Engine for Automobile: A Geometric Compression Ratio Control

Strategic Insights

— 1 min read

The patent WO/2011/142112 published on November 17 describes a diesel engine control device and method for an automobile. The invention, developed by Mazda Motor Corporation and its inventors, aims to improve fuel efficiency by controlling the geometric compression ratio in the engine main body. The abstract outlines the key features of the invention, including the use of injection control means to perform a main injection and two preceding injections prior to the main injection at specific regions within the operating region on the low-speed side.

Key Takeaways:

  • The geometric compression ratio in the engine main body is set to 15 or less to improve fuel efficiency.
  • The injection control means performs a main injection near the compression top dead center and two preceding injections, including a pilot injection and a pre-injection, to suppress ignition of the fuel injected by the pilot injection and shorten the ignition delay of the fuel injected by the main injection.
  • The pilot injection is performed at a timing such that at least part of the fuel spray reaches outside the cavity on the top face of the piston.
  • The pre-injection is performed at a predetermined timing after the pilot injection to suppress ignition and shorten the ignition delay.
  • The invention was filed on September 5, 2011, under Application No. PCT/JP2011/002571.
  • The patent was published on November 17, 2011, under Publication No. WO/2011/142112.

Statistics:

  • Geometric compression ratio: 15 or less
  • Number of preceding injections: 2 (pilot injection and pre-injection)
  • Timing of pilot injection: to ensure at least part of the fuel spray reaches outside the cavity on the top face of the piston
  • Timing of pre-injection: at a predetermined timing after the pilot injection
  • Engine main body: set to achieve a diesel engine for automobile
  • Inventors: Shinichi Morinaga, Daisuke Shimo, Keiji Maruyama, Hiroshi Minamoto, Naotoshi Shirahashi, and Daisuke Fukuda

Sources:

  • Publication No. WO/2011/142112, World Intellectual Property Organization, November 17, 2011
  • Application No. PCT/JP2011/002571, World Intellectual Property Organization, September 5, 2011
  • "http://www.wipo.int", World Intellectual Property Organization

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