Patent GB-913173-A (GB)
Title: Improvements in means for the automatic control of starting devices of carburettors for internal combustion engines
IPC: B21D7/06
Filed: 1959-12-18
Abstract: 913,173. Carburetters. SOC. INDUSTRIELLE DE BREVETS ET D'ETUDES. Dec. 18, 1959 [Jan. 9, 1959; June 3, 1959; June 5, 1959; June 23, 1959], No. 43133/59. Class 7(3) The putting out of action of the starting device of a carburetter depends on the temperature of an element of low thermal intertia (for example, hot gases or an electrical resistance) which begins to be heated perceptibly at the starting of an engine and the bringing into action depends on the temperature of an element of high thermal inertia (for example liquid such as cooling water or lubricating oil of the engine and the like on a solid) which begins to cool perceptibly at the stopping of the engine. The Specification refers to starting devices which regulate the free cross-section of the passage for the air fuel mixture or enrich the mixture either by measuring the vacuum which acts on the normal delivery orifices of the carburetter by closing a starter choke valve or by causing supplementary delivery orifices to deliver leg opening on auxiliiary starting carburetter. The starting device may be controlled by a bimetallic strip or a capsule filled with an expansible fluid. Referring to Figs. 3 and 4 when the engine is started heated air is drawn through the duct 13 and the bimetallic strip 5 rapidly reaches the temperature at which the starting device is to be rendered inoperative. When the engine is stopped hot fluid which is situated in the chamber 14 keeps the chamber 9 at a sufficient temperature so that the bimetalilc strip S only very slowly reaches the temperature at which the starting device is put back into operation. According to another embodiment the thermosensitive system is constituted by two separate members, the first being subjected to the temperature of the element of low thermal inertia and controlling the bring- ing into action and putting out of action of the starting device and the second being subjected to the temperature of the liquid of high thermal inertia and operating a mechanism adapted to lock the starting devices in its inactive condition. According to a third form of embodiment the bimetallic strip 5 is subjected to the temperature of an electrical resistance whose supply circuit is closed when the engine is started and remains closed as long as the temperature of the liquid of high thermal inertia is above a given limit. According to a fourth form of embodiment shown diagrammatically in Fig. 9 the control of the starting device is constituted by an assembly of two thermosensitive members 41, 42, the first of which is subjected to the temperature of an element of low thermal inertia and the second to the temperature of a liquid of high thermal inertia. In Fig. 10 when the engine heats up apart from the fact that the thermosensitive member 5 gradually puts the starting device out of action the water or oil or other liquid having a high thermal inertia which acts on the temperature of the member 26 also increases in temperature. As soon as this temperature reaches a predetermined value the arm 36 comes into contact with the stud 35 and the circuit supplying the electromagnet 48 closes causing the displacement to the right of Fig. 10 of the rod 47 thus shifting the thermosensitive member. The liquid of high thermal inertia may act not by way of an electromagnet 48 but directly by a rod coupled to a thermosensitive member. In another modification of Fig. 10 an electrical resistance may be employed to heat the thermosensitive member 5.