GB523554A - Improvements in and connected with precombustion chambers for internal combustion engines - Google Patents

Abstract

523,554. Oil engines. DAIMLER-BENZ AKT.-GES. Jan. 4, 1939, No. 315. Convention date, Jan. 5, 1938. [Class 7 (iii)] A pre-combustion chamber communicates with the cylinder space through a narrow passage formed with a number of alternating enlargements and constrictions, e.g. undulations. As shown in Fig. 3, the passage is formed by annular discs 12 separated by spacer rings 11 and held against the lower part 4 of the precombustion chamber, preferably against a ring 9, by a screwed insertion 13. During starting and slow running, part of the fuel from a nozzle 5 passes directly through the passage, which may be cylindrical, bent or flared towards one or both ends. The chamber may be provided with heat-insulating spaces 7 and the discs may have projections to reduce contact with the insertion 13. Smaller lateral holes may also be provided in the discs. One of the discs may be constructed of insulating material, such as ceramic material, and act as an incandescent igniter. Alternatively, an incandescent plug 8 or an incandescent ring set in the wall of the chamber may be used at starting. In Fig. 4 the rings 11 are omitted and the discs 12 have thickened rims and bent inner edges 12<1>. In modified constructions (a) the passage has a number of parallel ribs perpendicular to the axis of the chamber and (b) a single or multiple start screw thread is cut in the walls of the passage. Moreover, the passage may be located tangentially to the chamber the passage and the fuel injector being coaxial as in the other constrictions. In Fig. 12 is shown an arrangement in which the fuel nozzle is located in the cylinder space the fuel jet traversing the space before entering the pre-combustion chamber.