A totally-enclosed main motor comprising: a stator; a rotor including a rotor core disposed on an inner circumferential side of the stator, and a frame enclosing the stator and the rotor, and characterized by a cooling fan attached to an end portion on a counter driving side of the rotor core, the cooling fan partitioning an inside and an outside of the main motor, and a rotor shaft attached to the rotor core, a hollow section being provided in the rotor shaft from an end face on the counter driving side to at least a front of an attachment place of the cooling fan in an axial direction, a ventilation hole communicating with the hollow section being provided on a side surface of the rotor; a further cooling fan attached to an end portion on a driving side of the rotor core, wherein the further cooling fan can agitate air in the totally-enclosed main motor; a first bracket connected to an end portion on a driving side of the frame; a second bracket connected to an end portion on the counter driving side of the frame, an exhaust port, at least a part of which is disposed more on an inner diameter side than an end portion on the counter driving side of a main plate of the cooling fan is disposed on the inner diameter side, being provided in the second bracket, the second bracket configuring a labyrinth between the second bracket and the end portion of the main plate; a first bearing section provided in the first bracket, the first bearing section supporting the rotor shaft; and a second bearing section provided in the second bracket, the second bearing section supporting the rotor shaft and being disposed more on the counter driving side than the ventilation hole is disposed on the counter driving side, wherein the main plate and the second bearing section form a wind path, and wherein the cooling fan is configured to rotate according to a rotation of the rotor to cause cooling wind enter the hollow section from an end face of a rear end portion of the rotor shaft, cause the cooling wind pass the ventilation hole and flow through the wind path, and exhaust the cooling wind from the exhaust port. a stator; a rotor including a rotor core disposed on an inner circumferential side of the stator, and a frame enclosing the stator and the rotor, and characterized by a cooling fan attached to an end portion on a counter driving side of the rotor core, the cooling fan partitioning an inside and an outside of the main motor, and a rotor shaft attached to the rotor core, a hollow section being provided in the rotor shaft from an end face on the counter driving side to at least a front of an attachment place of the cooling fan in an axial direction, a ventilation hole communicating with the hollow section being provided on a side surface of the rotor; a further cooling fan attached to an end portion on a driving side of the rotor core, wherein the further cooling fan can agitate air in the totally-enclosed main motor; a first bracket connected to an end portion on a driving side of the frame; a second bracket connected to an end portion on the counter driving side of the frame, an exhaust port, at least a part of which is disposed more on an inner diameter side than an end portion on the counter driving side of a main plate of the cooling fan is disposed on the inner diameter side, being provided in the second bracket, the second bracket configuring a labyrinth between the second bracket and the end portion of the main plate; a first bearing section provided in the first bracket, the first bearing section supporting the rotor shaft; and a second bearing section provided in the second bracket, the second bearing section supporting the rotor shaft and being disposed more on the counter driving side than the ventilation hole is disposed on the counter driving side, wherein the main plate and the second bearing section form a wind path, and wherein the cooling fan is configured to rotate according to a rotation of the rotor to cause cooling wind enter the hollow section from an end face of a rear end portion of the rotor shaft, cause the cooling wind pass the ventilation hole and flow through the wind path, and exhaust the cooling wind from the exhaust port.