Internal combustion engine in-cylinder braking device

Abstract

The invention discloses an internal combustion engine in-cylinder braking device which comprises a rocker arm shaft, an air inlet rocker arm assembly and an exhaust rocker arm assembly. A braking valve assembly is arranged on the exhaust rocker arm assembly, hydraulic tappet assemblies are arranged at the valve ends of the rocker arm assemblies respectively, and the hydraulic tappet assemblies are matched with valve bridge assemblies. Each hydraulic tappet assembly comprises a shell, tappets are elastically matched in the shells, elephant feet are assembled on ball heads of the tappets, main oil ducts are axially arranged on the tappets, first one-way valve assemblies are arranged between the upper ends of the main oil ducts and an upper oil cavity, exhaust holes are formed in the shells, oil inlet holes and oil outlet holes are radially formed in the tappets, and reducing sections are arranged on the oil outlet holes. A lubricating oil channel in the rocker arm shaft communicates with the oil inlet holes through oil inlet channels, the oil outlet holes communicate with the inner cavities of the elephant feet, and a braking control oil channel communicates with the braking valve assembly through a braking oil channel on a rocker arm. The internal combustion engine in-cylinder braking device has the advantages that the structure is reasonable, the braking reliability and safety can be improved, the valve clearance does not need to be adjusted, engine noise can be reduced, and NVH is improved.

Description

technical field

[0001] The invention relates to the technical field of automobile internal combustion engine manufacturing, in particular to an internal combustion engine cylinder braking device. Background technique

[0002] With the continuous development of my country's road transportation, all kinds of medium and heavy commercial vehicles have entered the transportation field of different industries, and the safety during transportation is the top priority. The braking performance of various medium and heavy-duty commercial vehicles during transportation is very important, especially when driving downhill, the driving safety is not optimistic. When going downhill for a long time, the driver must frequently use the brakes to decelerate the brakes, which will cause the brakes to overheat, causing the brakes to gradually decrease in braking efficiency or even fail. It is more serious on rugged mountain roads and long-slope roads. Some medium and heavy-duty commercial vehic...

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