A torque limiter (30, 70) comprising: a first rotary member configured to be rotated by a drive source; at least one first friction member engaged with the first rotary member; at least one second friction member arranged so as to overlap the first friction member, and configured to rotate with rotation of the first rotary member by using frictional force generated between the second friction member and the first friction member; and a second rotary member engaged with the second friction member;wherein the first friction member and the second friction member (34, 72) are plate-shaped; the first rotary member and the second rotary member are pivotally supported by an identical rotary shaft, and while either of the first rotary member and the second rotary member is fixed to the rotary shaft, the other one is supported so as to be rotatable about the rotary shaft; the first friction member and the second friction member are housed in a housing part in the first rotary member while being stacked on each other, and the second rotary member is arranged while pressing a stack of the first friction member and the second friction member; characterized in that the first rotary member and the second rotary member are gears, and the first rotary member is configured to be meshed with a first gear that is rotated by the drive source and the first rotary member is configured to be rotated by rotation of the drive source, and the second rotary member is configured to be meshed with a second gear that rotates a target to be driven and the second rotary member is configured to be rotated by rotation of the target to be driven. a first rotary member configured to be rotated by a drive source; at least one first friction member engaged with the first rotary member; at least one second friction member arranged so as to overlap the first friction member, and configured to rotate with rotation of the first rotary member by using frictional force generated between the second friction member and the first friction member; and a second rotary member engaged with the second friction member;wherein the first friction member and the second friction member (34, 72) are plate-shaped; the first rotary member and the second rotary member are pivotally supported by an identical rotary shaft, and while either of the first rotary member and the second rotary member is fixed to the rotary shaft, the other one is supported so as to be rotatable about the rotary shaft; the first friction member and the second friction member are housed in a housing part in the first rotary member while being stacked on each other, and the second rotary member is arranged while pressing a stack of the first friction member and the second friction member; characterized in that the first rotary member and the second rotary member are gears, and the first rotary member is configured to be meshed with a first gear that is rotated by the drive source and the first rotary member is configured to be rotated by rotation of the drive source, and the second rotary member is configured to be meshed with a second gear that rotates a target to be driven and the second rotary member is configured to be rotated by rotation of the target to be driven.