Endoscope cleaning sheath, and endoscope apparatus and endoscope comprising the cleaning sheath

An endoscope apparatus, comprising:

• an endoscope provided with at least an observation window at a distal end portion of an insertion portion;
• an endoscope cleaning sheath comprising a tube body having an endoscope disposition hole in which an insertion portion of the endoscope is inserted and disposed, at least one liquid supply hole that supplies a liquid such as water, and at least one gas supply hole that supplies a gas such as air;
• and a distal end configuration portion that is a cylindrical body that is provided in a fixed condition at a distal end portion of the tube body, and has a fluid mixing portion that mixes a liquid and a gas by causing a liquid that is supplied through the liquid supply hole and a gas that is supplied through the gas supply hole to merge and a concave portion configuring an ejection opening that ejects a fluid mixture that is mixed at the fluid mixing portion towards an observation window of the endoscope that is inserted and disposed in the endoscope disposition hole at a contact surface at which a distal end surface of the tube body and a distal end surface of the insertion portion of the endoscope contact each other;
• a liquid supply apparatus including a liquid supply pump and a liquid supply tank that supplies a liquid to the liquid supply hole through a fluid channel that is connected to a liquid supply portion that is provided in a communicating condition with respect to the liquid supply hole provided to the tube body;
• a gas supply apparatus including a gas supply pump that supplies a gas to the gas supply hole through a fluid channel that is connected to a gas supply portion that is provided in a communicating condition with respect to the gas supply hole provided to the tube body;
• and
• a control apparatus that controls at least either supply of a liquid to the liquid supply hole from the liquid supply apparatus or supply of a gas to the gas supply hole from the gas supply apparatus.

An endoscope having an observation window at a distal end surface of an insertion portion, including:

• a liquid channel configuring channel for a liquid;
• a gas channel configuring a channel for a gas;
• a fluid mixing portion in which the liquid channel and the gas channel merge at the distal end surface, and which mixes the liquid and the gas that are supplied;
• and
• an ejection portion that ejects a fluid mixture that is mixed at the fluid mixing portion towards the observation window.