METHOD FOR EVALUATION OF TECHNICAL CONDITION OF CYLINDER-PISTON GROUP OF INTERNAL COMBUSTION ENGINE Russian patent published in 2024 - IPC G01M15/04 

FIELD: measurement and testing.

SUBSTANCE: invention can be used in tests and technical diagnostics of machines, in particular, internal combustion engines (ICE). Disclosed is a method for assessing the technical state of a cylinder-piston group of ICE (1), according to which the ICE is started up and heated to the rated temperature, the fuel supply is stopped and the ICE is stopped. Primary converter (3) and external source of mechanical energy (4) are connected to crankshaft (CS) (2). Measuring device (7) is connected to primary converter (3), CS rotational speed sensor (5) and camshaft position sensor (6). External source of mechanical energy (4) is switched on and ICE CS is cranked with starting frequency, thereafter, measuring device (7) determines the current position of the piston of each ICE cylinder separately with period of 2 degrees of CS rotation; simultaneously the moment of resistance to cranking of the CS is recorded. Obtained values of the moment of resistance to cranking of the CS are compared with the position of the piston of each cylinder, an approximating dependence of the change in the moment of resistance to cranking of the ICE CS on the angle of rotation of the CS is established. Based on the obtained dependence, determining the maximum peak values arising due to the action of the forces of resistance to air compression at the compression stroke of each cylinder, and minimum peak values arising due to action of compressed air pressure on piston at expansion stroke of each cylinder. Obtained values are used to calculate the average reduction in the moment of resistance to cranking of the CS at the expansion stroke of each cylinder for at least 10 revolutions of the CS. Maximum average value of reduction of moment of resistance to cranking of CS from calculated is taken as nominal value, it is compared with average values of reduction of moment of resistance to cranking of other cylinders and conclusion is made on technical condition of cylinder-piston group of ICE.

EFFECT: invention makes it possible to reduce labour intensity and increase efficiency of measurements.

1 cl, 4 dwg