Douwe EgbertsEgberts CAFITESSE 300, Руководство по обслуживанию, Страница: 17 / 100

Spark Plugs
Chapter 2 Spark Plugs
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Uses the world's first and the world's
smallest ultra-fine 0.4-mm diameter
iridium tip for the center electrode. This
lowers the required voltage and greatly
improves ignitability.
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The inside of the ground electrode
has a U-shaped groove to secure the
large space required for flame core
formation. This provides superior
ignition performance with low spark
voltage without enlarging the plug gap.
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The ground electrode tip is cut to a
shape with a tapered tip. This reduces
the quenching effect and greatly
improves ignitability.
Taper cut ground electrode
U-groove ground electrode
Ultra-fine 0.4-mm diameter iridium
alloy center electrode
Increased center electrode projection Insulator projection All-round laser welding
Terminal Nut Built-in high-reliability resistor Plated with highly corrosion resistant nickel
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The finer the electrodes, the more
the potential concent-rates at the
electrode tip and the stronger the
electrical field, so the lower the
required voltage. Therefore, reliable
combusion is obtained over a wide
range and engine starting and
acceleration are improved.
Normal spark plugs
Weak
Electrical field strength
Strong
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Electrical field strength shown using FEM analysis
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