Abstract: A humidity controller has a humidity controlling element disposed in the opening of a chamber and comprising a hydrogen ion conductor membrane, porous electrodes disposed on two surfaces of the hydrogen ion conductor membrane and collecting electrodes disposed on opposite surfaces of the porous electrodes. Each of the collecting electrodes is disposed over an area than the whole area of each surface of the hydrogen ion conductor membrane such that the current density at a portion of the hydrogen ion conductor membrane where no collecting electrode is located is reduced by at most 1/2, thereby reducing the stress due to the difference between the thermal expansion coefficients of the porous electrodes and the collecting electrodes and limiting disconnection between these two groups of electrodes. The difference between the humidity control performance of this humidity controller and that of an arrangement in which collecting electrodes are disposed over the whole surfaces of the porous electrodes is small.

Abstract: The present invention relates to a magnetic disc apparatus having a dehumidifying element for removing the moisture flowing from a vent into the apparatus, and the magnetic disc apparatus according to the present invention is provided with a dehumidifying element having a humidity controlling element comprising a hydrogen ion conductor and a pair of porous filmy electrodes which sandwich the conductor therebetween. Applying the voltage to the humidity controlling element, the moisture in the apparatus, after contacting the electrode provided on the central side of the apparatus, is supplied to a hydrogen ion conductor and electrolyzed. The hydrogen ions obtained by electrolysis move toward the electrode provided on the peripheral side of the apparatus, where at least either of the hydrogen or water is evolved to advance the dehumidification in the apparatus.

Abstract: Apparatus for regulating the humidity inside a semi-sealed, partly air-permeable container for a magnetic disk drive. An opening provided in the semi-sealed container is sealed by an insulated humidity regulating element which includes a hydrogen ion conductor (which may be a solid electrolyte) and porous film-like first and second electrodes that are bonded to respective surfaces of both sides of the hydrogen ion conductor. A DC voltage is impressed across both electrodes to regulate the humidity.

Abstract: A laser welding method and apparatus for welding stacked coated members in which voids in the welds are positively eliminated. A spacer is disposed between the two members to be welded. This provides a path for discharging gas formed by heating the coating material. The method and apparatus of the invention are useful for the laser welding of base members coated with metals having a lower melting point than the metal of the base, paints and oils. Preferably, the width of the gap is in a range of 0.1 mm to 0.5 mm.