COUNTER-FLOW COOLING SYSTEM MULTISTAGE ROOT TYPE VACUUM PUMP

摘要

PURPOSE:To avoid going into complication in structure and oversize in type as well as to make a counter-flow cooling effect attainable in an effective manner despite a relatively simple construction, by using a new constitution method for a multistage root type vacuum pump composed of a counter-flow cooling system. CONSTITUTION:A discharge port 14 of a first pump section 1 and a suction port 43 of a second pump section 4 are connected with each other through connecting pipe lines 31, 32 and 33, while a cooler 36 is installed in position between both these connecting pipe lines 31 and 32, branching off from the connecting pipe line 32, and contraflow pipe lines 34 and 35 connected to each of inflow ports 161 and 162 for counter-flow cooling gas of a casing 11 in the first pump section 1 are installed. With the same way and so forth, a discharge port 44 of the second pump section 4 and a suction port 73 of a third pump section 7 are connected with each other through connecting pipe lines 61-63, while contraflow pipe lines 64 and 65 connected to each of these inflow ports 161 and 162 for a cooler 66 and counter-flow cooling gas are installed. In addition, discharge pipes 81 and 82 are connected to a discharge port 74 in the third pump section 7, installing a cooler 85 and counter-flow pipe lines 83 and 84 connected to each of inflow port 761 and 762 are installed. With this constitution, effective counter-flow cooling can be performed despite a simple construction.