Carbon-Deposit Protection System For A Sheathed-Element Glow Plug Having A Gas Conduit For Pressure Measurement

Abstract

A sheathed-element glow plug for an internal combustion engine, made up substantially of a plug housing and a glow element disposed in the plug housing, having a gas conduit for measuring the combustion chamber pressure. A gas-permeable filter element, provided according to the present invention in the gas conduit, prevents the penetration of carbon residues or combustion residues into the interior of the sheathed-element glow plug, or reduces particle entry to a tolerable level.

Description

FIELD OF THE INVENTION [0001] The invention relates to a sheathed-element glow plug for an internal combustion engine, made up substantially of a plug housing and a glow element disposed in the plug housing, having a gas conduit for measuring the combustion chamber pressure. DESCRIPTION OF RELATED ART [0002] For good starting and warmup behavior at low temperatures, diesel engines require a heat source that preheats either the gas mixture, the intake air, or the combustion chamber. For passenger-car engines, the use of sheathed-element glow plugs is generally proposed. These encompass a plug housing and a glow element that projects out of the plug housing and, in its installed state, projects out of the cylinder head into the combustion chamber of an internal combustion engine. As a rule, the glow elements of the sheathed-element glow plugs project 4 mm into the combustion chamber of the internal combustion engine, and heat the diesel / air mixture. The glow temperature that is reache...

AI Technical Summary

Benefits of technology

[0011] It is an object of the invention to present a sheathed-element glow plug in which the penetration of carbon residues or combustion residues into the interior of the sheathed-element glow plug is prevented or at least reduced to a tolerable level.

[0014] If the filter element is fitted into the combustion-chamber end of the gas conduit, the penetration of carbon residues or combustion residues into the gas conduit is also prevented or at least reduced. Any possible cross-sectional constriction resulting from deposited particles is thereby counteracted, and clogging of the gas conduit is prevented.

Problems solved by technology

The filter element obstructs the gas conduit extending next to or within the sheathed-element glow plug so that carbon residues or combustion residues cannot reach the particularly sensitive pressure sensor.

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