Automatic transmission device

An automatic transmission device that changes a speed of power input to an input member to output the power to an output member, characterized by comprising:

• a first planetary gear mechanism including first to third rotary elements that form a sequence of the first rotary element, the second rotary element, and the third rotary element when arranged in an order at intervals corresponding to gear ratios in a velocity diagram;
• a second planetary gear mechanism including fourth to sixth rotary elements that form a sequence of the fourth rotary element, the fifth rotary element, and the sixth rotary element when arranged in an order at intervals corresponding to gear ratios in a velocity diagram;
• a third planetary gear mechanism including seventh to ninth rotary elements that form a sequence of the seventh rotary element, the eighth rotary element, and the ninth rotary element when arranged in an order at intervals corresponding to gear ratios in a velocity diagram;
• a fourth planetary gear mechanism including tenth to twelfth rotary elements that form a sequence of the tenth rotary element, the eleventh rotary element, and the twelfth rotary element when arranged in an order at intervals corresponding to gear ratios in a velocity diagram;
• a first coupling element that couples the first rotary element, the sixth rotary element, and the eleventh rotary element to each other;
• a second coupling element that couples the second rotary element and the ninth rotary element to each other;
• a third coupling element that couples the third rotary element and the eighth rotary element to each other;
• a first clutch that engages and disengages the second coupling element and the tenth rotary element with and from each other;
• a second clutch that engages and disengages the fifth rotary element and the twelfth rotary element with and from each other;
• a third clutch that engages and disengages the fourth rotary element and the tenth rotary element with and from each other;
• a first brake that is disengageably engaged so as to hold the fifth rotary element stationary with respect to an automatic transmission device case;
• a second brake that is disengageably engaged so as to hold the fourth rotary element stationary with respect to the automatic transmission device case;
• and
• a third brake that is disengageably engaged so as to hold the seventh rotary element stationary with respect to the automatic transmission device case, wherein:
• the input member is connected to the tenth rotary element;
• and
• the output member is connected to the third coupling element.