Screw compressors

A screw compressor, comprising:

• a housing, including a housing body and a housing cap, wherein the housing cap is engaged with the housing body and encloses an end of the housing body;
• a motor rotor, including an effective sensing section;
• a motor stator, surrounding the motor rotor;
• and
• a helical screw rotor, including a helical screw section, a motor coupling section, a first supporting section interposed between the helical screw section and the motor coupling section, and a second supporting section located opposite to the motor coupling section, wherein the first supporting section and the second supporting section are sleeved with a first bearing and a second bearing, respectively, and the motor coupling section and the motor rotor are coupled with each other and rotate synchronously together;
• characterized in that:
• the helical screw rotor further includes an extension section extending from the motor coupling section and exceeding the effective sensing section of the motor rotor, and the extension section is provided with a thread hole;
• and that the screw compressor further comprises a motor rotor stop, a screw fastener, and a third bearing, wherein the motor rotor stop includes a base portion, and a first flange portion and a second flange portion extending from opposite sides of the base portion, respectively;
• and wherein the first flange portion is sleeved with the extension section and abuts upon the effective sensing section of the motor rotor, and wherein the screw fastener extends through the base portion and is threadedly engaged into the thread hole and then biases axially upon the base portion, and wherein the third bearing is interposed between the second flange portion and the housing cap.