INTERCOOLERLESS WATER COOLING TYPE FOUR-STAGE ROOTS VACUUM PUMP

摘要

PURPOSE: To dispense with installation of an intercooler by providing a passage for communicating compression chambers with each other in the interior of a pump outer component formed by parallelly arranging plural compression chambers, and cooling the pump outer component by water passing through the passages formed in the component. ;CONSTITUTION: A front first stage compression chamber 7, a rear third stage compression chamber 9, a front second stage compression chamber and a rear fourth stage compression chamber 10 are provided in a pump outer component 1, and Roots-type rotors 11, 13 provided on a common shaft are accommodated in the first and third stage compression chambers 7, 9. Roots-type rotors 12, 15 provided on a common shaft are accomodated in the second and fourth compression chambers 8, 10. Pulleys 17, 18, which are interlocked and driven by one motor, are fixed to the end parts of the respective rotor shafts 14, 16, that are projected from a housing. A cooling passage is formed in such a manner as to surround the respective compression chambers 7-10 on the outer component 1, and cooling water is let flow through the passage to cool the outer component.;COPYRIGHT: (C)1995,JPO