GB331213A - Improvements in or relating to means for varying the compression space of the cylinde?s of internal combustion engines - Google Patents

Abstract

331,213. Graf, O. March 25, 1929. Controlling extent of travel; actuating controllers.-Means for controlling a motor which actuates mechanism for varying the cylinder clearance and throttle valve of an internalcombustion engine and which is responsive to the load on the engine, comprise a piston 4 in a cylinder 2 which is connected by a pipe 9 to the suction pipe 3 of the carburettor, or to the air inlet pipe in the case of a Diesel engine, and by a throttled opening 8 to the atmosphere. The piston is connected to a roller reversing switch 10 which when the movement of the piston is reversed rolls until a pin 13 strikes a fork 12, thus bringing alternative pairs of wiping contacts 14 - - 17 into contact with current bars 18 - - 20. This piston is also connected to stopping mechanism comprising a contact finger 5 which slides over a conductor 21 provided with an insulated plate 22. The conductor 21 is moved by a nut on the shaft 34 of the motor so that when the requisite movement has taken place, the plate 22 insulates the finger 5 and the motor stops. The movement may be indicated by a pointer on the conductor 21 or by a contact finger on the conductor 21 which wipes over an electrical resistance, variation of which is shown by a measuring instrument. A master switch 26 is provided and if the apparatus is to be controlled by hand, the cylinder 2 is omitted and the switch roller 10 and the finger 5 are connected with, and moved by, the accelerator pedal or the liquid fuel valve. Figs. 5 and 6 show a modified controller. A handle 44, having a pointer 58, rotates a member 45 having a reversing roller switch 48 and a sliding contact 46, when the handle 44 is rotated, the switch 48 rotates until stopped by one of the pins 64 and thus makes the appropriate contacts with contact bars 50 which are connected through a terminal box 60 to a corresponding terminal box on the motor, which rotates through a flexible shaft, or a synchronized motor, or a solenoid and pawl mechanism, and a worm 52, a contact wheel 51 until an insulation 55 breaks contact with the contact 46 and thus stops the motor. A scale 57 on the wheel 51, indicating the movement of the motor, is visible through a window in the casing.