Blower for a gas laser

A gas laser blower comprising:

• a blower housing forming an internal chamber having a vacuum discharge port,
• an oil passage formed so as to extend within a side wall forming the blower housing,
• an upper bearing and a lower bearing respectively mounted on an upper portion and a lower portion of said blower housing,
• a shaft mounted with a vane at an upper end thereof and a pump at a lower end thereof respectively and supported by said upper bearing and said lower bearing, and
• an oil reservoir formed at the bottom of the housing, in which oil within said oil reservoir is supplied to the lower bearing and to the lower portion of the upper bearing by operating said pump, the oil is passed through said oil passage and then returned to said oil reservoir,
• wherein the oil passage is formed such that the lower end thereof is positioned at the inner wall of a housing which forms an oil reservoir and also opens onto the interior of the housing at a level below the oil level so that said internal chamber and said oil passage are separated by the oil within said oil reservoir.