Ventilation structure for transmission

A ventilation structure for a transmission comprising:

• a transmission case accommodating the transmission;
• a vent valve provided with a vent pipe penetrating an inside and outside of the transmission case and releasing air to an outside of the transmission case when internal pressure reaches a predetermined value or more;
• an oil warmer;
• and
• a warmed oil supply pipe disposed inside the transmission case, wherein the warmed oil supply pipe supplies oil warmed by the oil warmer into the transmission case,
• wherein the transmission case comprises:
• a first case to which the vent valve is disposed;
• a second case joined with the first case;
• a plate member interposed between mating surfaces of the first case and the second case;
• a first chamber and a second chamber formed inside the first case;
• and
• a shielding part shielding the first chamber and the second chamber in the first case,
• wherein the first chamber is formed adjacent to the plate member in the first case to introduce thereinto air inside the transmission case from an introduction opening,
• wherein the second chamber leads out air from a lead-out hole to a vent valve,
• wherein the shielding part shields the first chamber and the second chamber excluding a ventilation opening so that the first chamber has a larger volume than the second chamber, and
• wherein the introduction opening of the first chamber is formed by opening a lower end of the first chamber and separating a side surface of the first chamber using the plate member.