Handcart

1. A handcart comprising:

a support frame;

a container configured to be rotated relative to the support frame;

a lock member disposed on one of the support frame and the container, the lock member configured to move between a locking position at which the lock member restricts rotation of the container relative to the support frame and an unlocked position at which the lock member allows the rotation of the container relative to the support frame; and

a retainer member disposed on the other of the support frame and the container, the retainer member configured to move between a retaining position at which the retainer member restricts a movement of the lock member from the unlocked position to the locking position and a non-retaining position at which the retainer member allows the movement of the lock member from the unlocked position to the locking position,

wherein the lock member is configured to move from the locking position to the unlocked position and be maintained at the unlocked position by a movement of the retainer member from the non-retaining position to the retaining position.

2. The handcart according to claim 1 , further comprising:

a biasing member configured to bias the lock member, wherein under a state where the lock member is at the unlocked position, the biasing member is configured to, via the lock member, bias the retainer member from the non-retaining position to the retaining position.

3. The handcart according to claim 1 , wherein

the lock member is disposed on the support frame, and

the retainer member is disposed on the container.

4. The handcart according to claim 1 , wherein

the retainer member comprises an operation portion configured to be operable by a user, and

in a top view of the handcart, the operation portion is disposed outward of the support frame.

5. The handcart according to claim 1 , wherein the retainer member is a crank member.