Abstract: A breather device that is attached to a case of a transmission and performs ventilation in the case, includes: a main body member including a storage portion with a closed bottom and an open upper end; and a cover member configured to close the upper end of the main body member and including a vent hole for ventilation to outside. The storage portion comprises a first chamber having, in a bottom portion, a communicating port communicating with an interior of the case, and a second chamber configured to receive a liquid entering from the vent hole.

Abstract: Since an oil level of oil in a first space housing a transmission mechanism is lower than an oil level of the oil in a second space housing a differential gear, not only is it possible to lubricate a drive pinion and a ring gear housed in the second space with a sufficient amount of oil while cutting the total amount of oil compared with a case in which the oil levels of the first space and the second space are both high, but it is also possible to reduce the resistance of oil to stirring in the second space by discharging excess oil building up in the second space to the first space via a second oil passage formed along an axial center of a pinion shaft, and to prevent the oil level of the first space from decreasing excessively, thus avoiding aeration of an oil pump.

Abstract: Since an oil level of oil in a first space housing a transmission mechanism is lower than an oil level of the oil in a second space housing a differential gear, not only is it possible to lubricate a drive pinion and a ring gear housed in the second space with a sufficient amount of oil while cutting the total amount of oil compared with a case in which the oil levels of the first space and the second space are both high, but it is also possible to reduce the resistance of oil to stirring in the second space by discharging excess oil building up in the second space to the first space via a second oil passage formed along an axial center of a pinion shaft, and to prevent the oil level of the first space from decreasing excessively, thus avoiding aeration of an oil pump.

Abstract: A breather device that is attached to a case of a transmission and performs ventilation in the case, includes: a main body member including a storage portion with a closed bottom and an open upper end; and a cover member configured to close the upper end of the main body member and including a vent hole for ventilation to outside. The storage portion comprises a first chamber having, in a bottom portion, a communicating port communicating with an interior of the case, and a second chamber configured to receive a liquid entering from the vent hole.