To eliminate the need for a lock and power for releasing the lock, to suppress power consumption in a battery, and to prevent a period when the drive unit can be driven by power supply from the battery from being reduced when a moved body can be locked in a still state when power supply from the battery to an electric motor is stopped.

The drive unit 1 comprises: the battery 10; the electric motor 12 that can be subjected to forward/backward drive A, B by power supplied from the battery 10 while being supported by a still side member 1a; the moved body 13 that can be rotated and driven by inputting power from the electric motor 12; and a locking mechanism 14 that permits only power transmission from the electric motor 12 to the moved body 13 in power transmission between the electric motor 12 and the moved body 13 while being provided between the electric motor 12 and the moved body 13, and at the same time can automatically lock the moved body 13 to the still side member 1a when the electric motor 12 is stopped.

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