Frictional engagement element and automatic transmission

A frictional engagement element, comprising:

• a plurality of friction plates arranged with clearances therebetween;
• a piston movable between a releasing position where the friction plates are brought into a released state, and an engaging position where the friction plates are brought into an engaged state by pressing the friction plates;
• and
• a first urging mechanism and a second urging mechanism configured to urge the piston in an engaging direction from the releasing position toward the engaging position, wherein:
• urging forces of both of the first urging mechanism and the second urging mechanism act on the piston from the releasing position to a first position in the engaging direction;
• the urging force of the first urging mechanism acts on the piston from the first position to a second position closer to the engaging position than the first position;
• the first position is a predetermined position where the piston does not abut against the friction plates;
• and
• the second position is a position where the piston abuts against the friction plates and the clearances are reduced.