Mower unit

A mower unit comprising:

• a mower deck;
• a plurality of blades mounted inside said mower deck and rotatable about vertical shafts supported to said mower deck, said mower deck defining, on one lateral side thereof, a discharge outlet for discharging cut grass cut by the plurality of blades;
• an opening and closing member configured to be moved to a closing position for closing said discharge outlet and also to an opening position away from said discharge outlet for opening the discharge outlet, said opening and closing member in said opening position extends along an outer face of said mower deck;
• a guide member for guiding cut grass from said discharge outlet to a lateral outer side, said guide member being switchable in its posture between a raised posture and a substantially horizontal posture;
• a retaining mechanism for retaining said guide member in the raised posture thereof, said retaining mechanism comprising a support member which is supported on said opening and closing member so as to support said guide member in said raised posture when said discharge outlet is closed;
• and
• wherein the mower deck has a cutting chamber for each of the plurality of blades, each cutting chamber having an inner surface with a cross-section taken at a vertical plane that passes through a respective one of the vertical shafts of the blades, the cross-section of the inner surface of each cutting chamber being curved closer toward the respective vertical shaft in an upward direction, and wherein an inner surface of the opening and closing member has a shape that corresponds to the inner surface of a corresponding cutting chamber.