Abstract: An oil leak detection device includes a pair of permanent magnets, a plurality of commutators, a coil, a pair of brushes, and a current sensor. An N-pole and an S-pole of the pair of permanent magnets face each other. The plurality of commutators are attached to an output shaft. The coil is wound onto the output shaft inside the pair of permanent magnets in the radial direction of the output shaft. The coil is electrically connected to the plurality of commutators. The pair of brushes are attached to a housing and are capable of coming into contact with each of the plurality of commutators. The current sensor detects an induction current flowing between the pair of brushes and the housing.

Abstract: A clutch includes a clutch disk that rotates by receiving motive power from an engine and a clutch plate switched between an engaged state in which it is engaged with the clutch disk and a disengaged state in which it is not engaged with the clutch disk. A controller calculates a coefficient of friction ? between the clutch disk and the clutch plate based on a time period ?t elapsed from a first time point when the number of relative rotations of the clutch disk and the clutch plate attains to a first number of rotations to a second time point when a second number of rotations smaller than the first number of rotations is attained, in a state in which the clutch disk rotates while transfer of motive power from the engine to the clutch disk is cut off and in the engaged state.

Abstract: Electrolytic plating can be carried out with a uniform thickness even when the resistance of a plating seed layer is comparatively high, thereby improving the formation precision of products and improving the yield of products. In a method of carrying out plating on a substrate, an insulating layer, which includes conductive parts that conduct electricity to the substrate, is formed on the substrate that is made of a resistor, a plating seed layer, which conducts electricity to the substrate via the conductive parts, is formed on the insulating layer, and a plating film is formed on the plating seed layer with the plating seed layer as a power supply layer.

Abstract: A writing instrument internally houses a miniature electronic calculator which includes a key input section comprising a single key which is subjected to a rotational or translational movement to select one of a plurality of switches. When the key is depressed against a bias applied thereto while in a position in which it has selected one of the switches, the selected switch is controlled thereby to input an associated information into an arithmetic unit of the calculator. The instrument case or key is marked with indicia which designate the key positions for the convenience of selecting input informations. The key input section comprises an insulating substrate on which an array of a plurality of stationary contacts are formed along the direction of movement of the key, a flexible insulating film disposed in opposing relationship with the stationary contacts, and a movable contact deposited on the side of film which faces the stationary contacts so as to extend in the direction of movement of the key.