Ball screw device

A ball screw device comprising:

• a nut including an internal thread and two outer peripheral raceway surfaces arranged between the internal threads;
• a screw shaft including an external thread and two inner peripheral raceway surfaces arranged between the external threads;
• a plurality of balls arranged on two rolling paths between the two outer peripheral raceway surfaces and the two inner peripheral raceway surfaces;
• and
• two circulation components configured to circulate the plurality of balls, one of the two circulation components being provided at one end of the nut and an other of the two circulation components being provided on an other end of the nut, wherein
• the internal thread and the external thread hold the plurality of balls,
• the nut includes:
• a cylindrical body having a cylindrical shape and including the external thread and the two outer peripheral raceway surfaces;
• and
• two return paths penetrating the cylindrical body in an axial direction parallel to an axis of the screw shaft, and
• each of the two circulation components includes:
• a main body fixed to the cylindrical body of the nut;
• two communication paths penetrating the main body and communicating the two rolling paths and the two return paths;
• a communication path partition wall between the two communication paths so as to partition the two communication paths;
• and
• two tongues protruding from the main body to the two rolling paths.