A rotary compressor includes a compressor housing that is provided with a refrigerant discharge portion and a refrigerant suction portion, and an accumulator that is fixed to the outer peripheral surface of the compressor housing and connected to the suction portion. The accumulator has a cylindrical body portion, which is formed of a resin material, an upper portion, which is formed of a metal material and closes an upper end of the body portion, and a lower portion, which is formed of a metal material and closes a lower end of the body portion, the upper portion is joined to the upper end of the body portion, and the lower portion is joined to the lower end of the body portion.

A supercharger rotor with reduced rotational inertia may result in increased performance of a supercharger. The rotor may include composite material and may be extrusion molded, injection molded, or otherwise molded or laid-up. In certain embodiments, the rotor may include a core with a central portion and one or more radially extending portions. The core may be extruded or formed of stacked sheets. A molded portion of the rotor, including one or more lobes, may be molded over a corresponding one of the radially extending portions. In other embodiments, a main portion of the rotor includes one or more lobes but no central hole nor a corresponding shaft extending between ends of the main portion. Instead, stub shafts are attached to the ends of the main portion. The increased performance may include decreased noise, decreased cost, increased reliability and/or durability, increased thermal efficiency, an increased power-to-weight ratio, etc.

The present application discloses a piston rod mechanism for an air compressor, along with an air compressor. The piston rod mechanism for an air compressor comprises: a rod and a piston fixedly connected to an output end of the rod, wherein an air vent is provided within the piston, allowing air to communicate between one side of the piston facing towards the rod and the other side away from the rod; an intake valve disposed at the piston, wherein the intake valve is configured to switch between a closed position where the air vent is closed and an open position where the air vent is opened, the intake valve being made of an elastomeric material. Accordingly, the piston rod mechanism for an air compressor, as described in the present application, is capable of reducing noise during operation.