Detection system for determining valve opening and closing moments

Abstract

The invention discloses a detection system for determining valve opening and closing moments. The detection system comprises a cylinder pressure sensor and a displacement sensor which are used for being installed on a cylinder cover of an engine, an electronic corner mark instrument used for being installed at the front end of a crankshaft of the engine, and a combustion analyzer connected with the cylinder pressure sensor, the displacement sensor and the electronic corner mark instrument. According to the detection system for measuring opening and closing moments of an engine valve in the invention, the non-contact eddy current displacement sensor is matched with the electronic angle marking instrument at the front end of the crankshaft to collect the valve lift of the engine in the ignition state, the valve opening and closing moment of the engine in the ignition state is accurately measured, and the accuracy of valve opening and closing measurement of the engine in the ignition state is guaranteed.

Description

Technical field [0001] The invention relates to the technical field of automobile engine testing, in particular to a detection system for determining the opening and closing time of a valve. Background technique [0002] The engine plays an extremely important role in the industrial field. When the engine is ignited, due to the inertial effect and thermal expansion of the valve train parts running at high speed, the opening and closing time of the engine valve is different from that under static conditions, and under different working conditions. The engine valve mechanism is compact, the valve opening and closing frequency is high, and the high temperature and high pressure environment of the valve is complicated and changeable. Therefore, it is difficult to measure the valve opening and closing time under the ignition state of the engine. Therefore, in order to ensure the intake of the engine cylinder Sufficient and thorough exhaust, the engine valve opening and closing time ne...

AI Technical Summary

Problems solved by technology

[0003] The current measurement method is mainly to measure the opening and closing moments of the engine valve under static conditions, specifically through the top dead center mark on the side of the flywheel and the mark on the camshaft, or the height dial indicator to determine the top dead center of the piston, and the graduation is installed on the flywheel Then use the height dial indicator to observe the opening and closing position of the valve, and the opening and closing time of the valve can be obtained through the dial. The current measurement method has great shortcomings. First, the existing measurement method is to measure under static conditions. The opening and closing timing of the engine valve does not take into account the inertial effect of the parts when the engine is ignited at high speed, and the thermal expansion of the valve and other parts. Therefore, the measurement results in this static state are inaccurate; Measure the difference between the opening and closing timing of the valve under different working conditions; finally, due to the influence of various factors when the internal combustion engine is running, there is a difference between the top dead center position in the working state and the static state

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