Abstract: A cooker has an external circulation path outside a heating chamber in which foods are to be placed. A blower sucks in gas inside the heating chamber, and forms, in the external circulation path, a gas flow that makes the sucked gas return to the heating chamber. Downstream of the blower, the external circulation path is provided with an exhaust port, in which a damper is provided. The damper closes the exhaust port during cooking, and opens the exhaust port when a door of the heating chamber is opened. After the damper is changed to a position of opening the exhaust port, the blower continues to operate until a predetermined condition is satisfied.

Abstract: A sub-cavity with an integral steam heater is provided in a ceiling portion of a heating chamber. A gas in the heating chamber is sucked into a blower through a gas suction opening and sent into an external circulation path. The gas passing through the external circulation path sucks steam from a steam producing device by using steam suction ejector. The gas that took the steam in enters into the sub-cavity, as the gas return opening, from the external circulation path. The steam contained in the gas is heated by the steam heater in the sub-cavity to become an overheated state, spouted out downward from spouting holes in the bottom face of the sub-cavity, and collides with an object to be heated. The external circulation path is constructed from a pipe with a circular cross-section.

Abstract: A steam cooker, wherein a sub cavity incorporating a steam heating heater is formed at the center of the ceiling part of a heating chamber. Steam in the heating chamber is sucked into an air blow device through a suction port and force-fed into the sub cavity through an external circulating passage. Gas passed through the external circulation passage sucks steam from a steam generator midway in the external circulation passage and enters from the external circulation passage into the sub cavity. The steam heated by the steam heating heater until it is brought into an superheated state is jetted downward from a plurality of upper gas jetting holes formed in the bottom panel of the sub cavity by such a force that makes the steam reach the bottom of the heating chamber so that the steam can be collided with a heated matter. The steam is raised on the outside of downward air flow and the convection of steam occurs in the heating chamber.

Abstract: A cooker has an external circulation path outside a heating chamber in which foods are to be placed. A blower sucks in gas inside the heating chamber, and forms, in the external circulation path, a gas flow that makes the sucked gas return to the heating chamber. Downstream of the blower, the external circulation path is provided with an exhaust port, in which a damper is provided. The damper closes the exhaust port during cooking, and opens the exhaust port when a door of the heating chamber is opened. After the damper is changed to a position of opening the exhaust port, the blower continues to operate until a predetermined condition is satisfied.

Abstract: A steam cooker, wherein a sub cavity incorporating a steam heating heater is formed at the center of the ceiling part of a heating chamber. Steam in the heating chamber is sucked into an air blow device through a suction port and force-fed into the sub cavity through an external circulating passage. Gas passed through the external circulation passage sucks steam from a steam generator midway in the external circulation passage and enters from the external circulation passage into the sub cavity. The steam heated by the steam heating heater until it is brought into an superheated state is jetted downward from a plurality of upper gas jetting holes formed in the bottom panel of the sub cavity by such a force that makes the steam reach the bottom of the heating chamber so that the steam can be collided with a heated matter. The steam is raised on the outside of downward air flow and the convection of steam occurs in the heating chamber.

Abstract: A sub-cavity with an integral steam heater is provided in a ceiling portion of a heating chamber. A gas in the heating chamber is sucked into a blower through a gas suction opening and sent into an external circulation path. The gas passing through the external circulation path sucks steam from a steam producing device by using steam suction ejector. The gas that took the steam in enters into the sub-cavity, as the gas return opening, from the external circulation path. The steam contained in the gas is heated by the steam heater in the sub-cavity to become an overheated state, spouted out downward from spouting holes in the bottom face of the sub-cavity, and collides with an object to be heated. The external circulation path is constructed from a pipe with a circular cross-section.