Cleaner

A mobile robot, comprising:

• a body;
• a mop module installed on the body and configured to clean using water;
• a water tank removably disposed in the body and configured to store the water to be supplied to the mop module;
• a water tank module installed on the water tank, the water tank module comprising:
• a hook configured to engaged with the body;
• and
• an operation button disposed on a surface of the water tank, the operation button being configured to operate the hook;
• and
• a detachable seating portion on which the water tank module is seated,
• wherein the water tank comprises:
• a circumferential surface on an exterior of the body, the circumferential surface forming a surface perpendicular to a horizontal plane when the water tank is coupled to the body;
• and
• a top surface perpendicular to the circumferential surface,
• wherein the operation button is disposed on the circumferential surface,
• wherein the hook is disposed on the top surface of the water tank,
• wherein the detachable seating portion is formed at a point where the circumferential surface and the top surface meet,
• wherein the detachable seating portion is a recess forming an opening in the circumferential surface that extends to the top surface,
• wherein the water tank module further comprises:
• a first return member configured to return the operation button to an initial position;
• a second return member configured to return the hook to an initial position;
• and
• a detachable housing configured to accommodate at least a part of the hook, a part of the operation button, and the second return member, and
• wherein the detachable housing comprises:
• a hook hole formed on a first surface of the detachable housing and being configured to receive the hook;
• and
• a button hole formed on a second surface of the detachable housing and being configured to receive the operation button, the first surface being perpendicular to the second surface.