Patent ID: 7836724

Claim:
A screw compressor comprising: a screw rotor; a cylinder for housing the screw rotor; and an economizer port provided in the cylinder and communicating with a compression chamber formed between the screw rotor and an inner face of the cylinder, the economizer port being configured and arranged to jet a refrigerant into the compression chamber before closing the compression chamber, the compression chamber being closed before the refrigerant jetted from the economizer port leaks to a low pressure side of the screw rotor, and the economizer port being formed along a length direction of a vane of the screw rotor, the economizer port having a maximum width measured along a width direction of the vane and a maximum length measured along the length direction of the vane with the maximum length of the economizer port being larger than the maximum width of the economizer port, with the economizer port being formed by a single elongated hole as viewed along a center axis of the hole.