US Patent 7902473 Key switch with exhaust structure

The present invention provides a key switch with an exhaust structure, which includes a keycap having a top surface and an inner surface with a cavity and an elastic member. The elastic member includes a protrusion and an elastic body. The protrusion is coupled with the inner surface of the keycap. A gas channel is formed between the cavity of the keycap and the protrusion of the elastic member. When an external force is applied to the top surface of the keycap to compress the elastic body, the gas within the elastic member can be exhausted through the gas channel of the elastic member.