摘要 |
<p>The invention concerns a pumping unit wherein the vacuum pump (100) is driven by a motor (3, 4) comprised in a common monobloc housing forming motor housing (5) and oil pan (18) containing a gear assembly (17) for coupling two parallel pump rotors (14). To complement the sealing conditions provided by a dynamic seal (6), the motor stator (4) consists of an electric coil embedded in an oil-tight and gas-tight resin, thereby not requiring other more expensive and bulky sealing means, reducing production cost and enhancing the pumping unit dependability.</p> |