Abstract: A tracheal connector is connected to a respiratory gas generator and a tracheal tube. The tracheal connector includes a tracheal connector body connected to the tracheal tube, a connector tube connected to the tracheal connector body and the respiratory gas generator, and a restriction mechanism configured to narrow a respiratory gas flow path configured to allow the respiratory gas to flow therein. The tracheal connector body includes a tracheal port connected to the tracheal tube, an exhaust port facing the tracheal port and configured to discharge at least expired air of the subject, and a respiratory port connected to the connector tube. The restriction mechanism is provided on the respiratory gas flow path between the respiratory port and the tracheal port.

Abstract: An improved injection molding nozzle shows a high hardness and is chemically stable so that the inner surface thereof is not corroded nor the gas or the fluid forced to penetrate into the gap between the injection molding nozzle and the valve pin seize the valve pin regardless of the temperature and the pressure of the material to be injected. Additionally, the valve pin is not pliable and does not give rise to a collapse on the part of the valve pin. The injection molding nozzle to be used for resin and molten metal is characterized in that it is made of a ceramic material and at least part of the outer periphery is covered with metal.