GB498504A - Improvements in and relating to internal combustion engines - Google Patents

Abstract

498,504. Starting. SOC. ANON. A. SAURER. April 5, 1937, No. 9567. Void. Convention date, April 9, 1936. [Class 7 (v)] In a method of starting Diesel or other engines by means of compressed air, compression is relieved during the compression stroke until the engine attains a speed of revolution sufficient to keep it running, whereupon the supply of compressed air is continued without relief of compression, until the ignition of the introduced fuel takes place. In the arrangement shown in Figs. 1 and 5, compressed air is supplied to the starting valve 4 on each cylinder through a conduit 5 controlled by a hollow slide valve 6 and an engine-driven rotary-disc valve 18 having an arcuate slot 19. Behind the valve 4 is a valve 12 adapted to connect the conduit 5 to the atmosphere at 14, and actuated by means of a piston 10 in a cylinder 9 connected to the compressed-air supply through a conduit 16 controlled by a port 17 in the valve 6 and by a disc valve 21 on the spindle of the valve 18. The valve 12 has an extension 15 adapted to engage the stem of the valve 4. For starting, the valve 6 is moved to the position shown in Fig. 1. Compressed air to effect the power stroke is admitted through the valve port 19 and opens the valve 4 ; on the compression stroke in another cylinder, a port 22 in the valve 21 admits air behind the piston 10 to effect the opening of the valves 12, 4 to relieve compression through the outlet 14 ; and at the end of the compression stroke, pressure in the conduit 16 is relieved through a groove 23 in the valve 21 and the valves 12, 4 are closed by their springs. When the engine has attained a sufficient speed in this way, the valve 6 is moved to the left, closing the port 17 but leaving open the port 7, so that starting air is still supplied but compression is not relieved. Fuel is injected, and when the engine runs normally, the valve 6 is moved to the right to close both ports 7, 17. In a modification, Figs. 6 and 9, a single rotary-disc valve has an arcuate port 19<1> and also a groove 25<1> for connecting the conduit 5' to a relief conduit during the compression stroke. The slide valve 6<1>, in addition to the ports 7, 17, has a groove 27<1> serving to relieve pressure in the conduit 16<1> when the valve 6<1> is moved to the left for operating the engine by means of compressed air without relief of compression, while the valve 12 is replaced by a piston 12<1> having an extension 15<1> for engaging the stem of the valve 4<1>. The cycle of operations in the engine cylinder is the same as in the first construction.