Abstract: An apparatus for injecting constant quantitative chemicals which is capable of injecting a chemical solution into ultra pure water without generating particulate contamination, and furthermore, the injection interval of the chemical solution to the cleaning nozzle is controlled in units of seconds within a range of a few seconds to 10 or more seconds, and the switching of the type of chemical solution and the changeover to ultra pure water cleaning can be conducted in a short period of time of approximately 1 second.

Abstract: A tightening device comprises an upper plate, a lower plate disposed below the upper plate in parallel thereto, a nut rotating gear supported by the lower plate so as to be rotatable in a horizontal plane, and a spur gear provided on an underside of the upper plate and meshable with the nut rotating gear for rotating the nut rotating gear. The upper plate has a portion fittable to a flange of an externally threaded member for preventing the rotation of the threaded member, while the nut rotating gear has a portion fittable to a nut. With the nut manually tightened on the threaded member in advance, the flange fitting portion of the upper plate is fitted to the flange, the nut is fitted in the fitting portion of the nut rotating gear, and the spur gear is thereafter rotated, whereby the nut rotating gear is driven to tighten up the nut on the threaded member.

Abstract: A reference range of tightening torques is predetermined relative to the rotation angle of a threaded member as normally tightened. In tightening up a nut on an externally threaded member, the tightening torque is detected by a torque sensor every time the nut is rotated through a specified angle, and whether the tightening torque relative to the rotation angle is within the reference range is judged by a microcomputer. The result of judgment is indicated by a light-emitting diode and a buzzer.