초록 ▼

An automatic decompression device for four-stroke engines comprises a cam gear, a counterweight, and an acting body. The cam gear includes a cam surface and a recess containing the acting body, and the counterweight includes a plate with a guide slot. Besides, the recess pierces the cam surface. Sin

An automatic decompression device for four-stroke engines comprises a cam gear, a counterweight, and an acting body. The cam gear includes a cam surface and a recess containing the acting body, and the counterweight includes a plate with a guide slot. Besides, the recess pierces the cam surface. Since the acting body is engaged to the guide slot of the counterweight and there exist external forces acting on the counterweight, the counterweight is forced to move the acting body upwardly or downwards by the guidance of the plate and the limitation of the guide slot. Consequently, the acting body is exposed beyond the cam surface or tucked into the recess. With the motion of the acting body, the opening and closing duty cycles of the intake and exhaust valves are biased. When the engine of the invention is static, the acting body is exposed beyond the cam surface to partially release the pressure of the engine's combustion chamber for manually starting the engine. When the engine of the invention is rotated at a relatively high speed, the acting body is tucked into the recess to make the engine's intake and exhaust valves working normally.

대표청구항 ▼

[ What is claimed is:] [1.] An automatic decompression device of engines comprising:a cam gear, including a cam surface on one side, a recess and a valley on the other side, said recess piercing said cam surface;a counterweight with a spring connected to one end of said counterweight, including a pl

[ What is claimed is:] [1.] An automatic decompression device of engines comprising:a cam gear, including a cam surface on one side, a recess and a valley on the other side, said recess piercing said cam surface;a counterweight with a spring connected to one end of said counterweight, including a plate with an inclined surface and a guide slot at the end of said counterweight apart from said spring, said spring and said counterweight located in said valley of said cam gear; andan acting body, located at the side of said cam gear apart from said cam surface, one end of said acting body located inside said recess and the other end of said acting body projected outside the side of said cam gear apart from said cam surface, the projected end of said acting body engaged to said guide slot, moved upwardly or downwards in said recess.