Power transmission path switching device and two-speed transmission

A power transmission path switching device, including

• a housing that does not rotate even during use,
• a friction engagement device having at least one friction plate and at least one separate plate that are supported so as to displace relative to each other in an axial direction, the friction engagement device connected by pressing the friction plate and the separate plate against each other, and disconnected by releasing the force pressing the friction plate and the separate plate against each other,
• a rotation transmission state switching device having a first member and a second member that are coaxially arranged with each other, the second member supported so as not to rotate relative to the housing, and having at least a free mode in which rotation of the first member with respect to the second member is allowed regardless of a direction of relative rotation between the first member and the second member and a lock mode in which rotation of the first member with respect to the second member is prevented regardless of the direction of relative rotation between the first member and the second member, and
• a control device having a function to switch the rotation transmission state switching device to the lock mode while maintaining the friction engagement device in a connected state after connecting the friction engagement device when connecting the friction engagement device and switching the rotation transmission state switching device to the lock mode, and a function to disconnect the friction engagement device and switch the rotation transmission state switching device to the free mode.