Cooling device and image forming apparatus

A cooling device, comprising:

• a heat receiving unit disposed to contact a surface of a temperature-increasing part a temperature of which increases during an image forming process;
• a radiation unit transferring heat from a cooling liquid,
• a tube for circulating the cooling liquid between the heat receiving unit and the radiation unit in a liquid circulation direction;
• a conveying unit conveying the cooling liquid through the tube;
• a coupling having an internal flow path and including a first end to which a first part of the tube is connected and a second end to which a second part of the tube is connected;
• an outlet for draining the cooling liquid from the tube;
• a container connected to the tube and containing the cooling liquid to be conveyed through the tube;
• and
• a connecting part attached to the container and to be connected to an air supplying unit supplying air into the tube,
• wherein at least one of the first part of the tube and the second part of the tube extends to a position lower than a position of the coupling.

A cooling device, comprising:

• a heat receiving unit disposed to contact a surface of a temperature-increasing part a temperature of which increases during an image forming process;
• a radiation unit transferring heat from a cooling liquid;
• a tube for circulating the cooling liquid between the heat receiving unit and the radiation unit in a liquid circulation direction;
• a conveying unit conveying the cooling liquid through the tube;
• a coupling having an internal flow path and including a first end to which a first part of the tube is connected and a second end to which a second part of the tube is connected;
• an outlet for draining the cooling liquid from the tube;
• a first connecting part provided at an upstream side in the liquid circulation direction of the radiation unit;
• a second connecting part that is attached to a part of the tube located upstream of the radiation unit in the liquid circulation direction and connectable to and disconnectable from the first connecting part;
• a third connecting part provided at a downstream side in the liquid circulation direction of the radiation unit;
• and
• a fourth connecting part that is attached to a part of the tube located downstream of the radiation unit in the liquid circulation direction and connectable to and disconnectable from the third connecting part, wherein
• at least one of the first part of the tube and the second part of the tube extends to a position lower than a position of the coupling, and
• the second connecting part is connectable to and disconnectable from the fourth connecting part.