GB505713A - Improvements in internal combustion engines with compression ignition - Google Patents

Abstract

505,713. Oil engines. KAMMER, G. S. April 13, 1938, No. 11419. [Class 7 (iii)] In a compression ignition engine having a combustion chamber separated from the cylinder space by closure valve elements or members, the valve members or elements are so moved as quickly to reduce the transfer cross-sectional area between the combustion chamber and the cylinder to zero or other minimum value shortly before the end of the compression stroke, and after the working piston has passed its inner dead centre gradually to increase the area to its maximum in such a manner that the cylinder pressure at any instant does not exceed a predetermined value, the maximum area. being retained until shortly before the end of the compression stroke. The transfer of combustion products from a separate combustion chamber 3 through a passage 10 to the working cylinder is controlled by a slide valve 5 actuated by a cam 13 which rapidly closes or almost. closes the valve near the end of the compression stroke, giving a minimum opening at the dead centre position, and then opens the passage gradually during the working stroke. The passage may be kept closed or almost closed during most of the compression stroke and then be opened suddenly, ready for the abovementioned closure, to produce turbulence in the chamber. To avoid excessive temperatures, the valve stem 17 may have a copper or silver insert and the insert may extend into the valve itself. In modifications, the slide valve 5 is replaced by an oscillating valve having a transverse port of constant cross-section or by a continuously rotating valve having a peripheral passage of varying width Corresponding to the form of the cam 13. In other forms, the combustion chamber 3 constitutes the valve and may have several spaced ports 8<1> ... 8<4>, Fig. 15, co-operating with corresponding ports 9<1> ... 9<4> formed in the valve casing and leading into an annular passage 30 which communicates with the passage 10 to the working cylinder. As shown in Fig. 17, the chamber 3 is formed with double walls to accommodate a cooling medium and the cooling insert 21 extends into the double walls, the chamber being rotated continuously to permit an opening 32 in or at the top of its walls to control the port 9 of the passage to the cylinder. When the combustion chamber is in the working piston, the passage is controlled by a piston moving parallel to the axis of the working piston and formed with a tapered end entering the passage or else by an oscillating valve 5, Fig. 21, having ports 12 co-operating with ports 8 in a stationary cylinder which obturates the passage.