Dry vacuum pump with improved gas discharging speed and pump cooling

1. Field of the Invention The present invention relates to a dry vacuum pump which includes multiple-tier cylinders, a gas flow path formed in a cover, and a cooling water flow path for thereby concurrently a heat of cooling rotation friction elements and a high temperature gas. In order to implement the present invention, in a dry vacuum pump, a cooling water inlet is formed in an outer surface of the rear cover, a cooling water outlet is formed in the front cover, and a cooling flow path is formed for guiding the cooling water flown through the cooling water inlet to circulate in each cylinder and intermediate cover, and in addition the cooling water flow path is formed in the inner and outer sides of the gas flow path formed in the rear cover and intermediate cover in a circular shape, and the cooling water flow paths which are formed in the inner and outer sides of the gas flow path are connected by a flow pipe which passes through the gas flow path for thereby concurrently cooling a gas flow path and the portions of a rotary shaft by a cooling water which flows through the cooling water flow path.