CAMSHAFT DECOMPRESSION MECHANISM OF INTERNAL COMBUSTION ENGINE

摘要

A camshaft decompression mechanism of an internal combustion engine includes a camshaft (3) provided with an intake cam, an exhaust cam (5) and a gear (9), and a U-shaped decompression device (1) hinged on the camshaft (3) by a pin roll (2). The upper end of the decompression device (1) has a decompression limit part (12) extending transversely, and the distance (H1) from the top end of the decompression limit part (12) to the center of the camshaft (3) is larger than the base circle radius (H2) of close stop distance end of the exhaust cam (5). The lower ends of two support arms of the decompression device (1) are provided with balance weight blocks (7) respectively. A release torsional spring (4) is sleeved on the pin roll (2), and one end of the torsional spring (4) is located on one end of a balance weight block (7) of the decompression device (1), while another end is located on the gear (9). The camshaft decompression mechanism is simple in structure and runs reliably.