(a) Field of the Invention
The invention relates to a reciprocating piston internal combustion engine having a glow plug preheat system. The invention also relates to such an engine which has a fan for cooling the engine oil and transmission oil and the heads, and an automatic mechanism for controlling the operation of the fan controlled by temperature transducers at different points of the engine.
(b) Description of Prior Art
A generic reciprocating piston internal combustion engine (RPICE) of this kind, having a mechanism for measuring conditions, such as temperature, throughout the engine is known from U.S. Pat. No. 4,348,990. However, in this patent the idea of using the output of the measuring mechanism for driving an electro-magnetically operated valve is addressed only generally. As regards a practical design of such an installation, it is apparent to one skilled in the art that several important questions are not dealt with, and that inventive effort and considerations would be involved in the answering of these questions. In addition, there are other units of a RPICE which could advantageously automatically control or regulate, for example, the glow plug installation to improve cold starting and cold running characteristics of the RPICE.
Although German Patent PS No. 27 43 059 teaches a system for controlling the glow plug installation in an engine having one glow plug or glow pin reciprocating piston unit, this particular control unit covers only the heating phase of the glow plug installation and the power supply thereto after the desired glow temperature has been reached. Other important factors, essential to the satisfactory operation of a RPICE are not covered in this reference.