Abstract: An electric oil pump including an electric motor, a first pump element that is driven to suck and discharge oil by output torque of the electric motor, a second pump element that is driven to suck and discharge the oil by the output torque of the electric motor, and a torque transmission switching member disposed on a torque transmission path extending between the electric motor and the second pump element. The torque transmission switching member is actuated to allow torque transmission between the electric motor and the second pump element when viscosity of the oil is not higher than a predetermined value, and interrupt the torque transmission between the electric motor and the second pump element when viscosity of the oil is higher than the predetermined value.

Abstract: A displacement sensor includes a plurality of conductive members, a semiconductor device, and a nonmagnetic conductor electrically connecting one of the conductive members and one of a low electric potential side and a high electric potential side of a power supply of the semiconductor device. The conductive member is electrically connected with the semiconductor device through a nonmagnetic conductor.

Abstract: A rotation angle sensor includes a rotatable magnet, at least one yoke located at a position to confront a magnetic pole, and a magnetic sensing device to sense magnetic flux density varying in accordance with a confronting area between the yoke and the magnet. The yoke is electrically connected with the magnetic sensing device through a nonmagnetic conductor.

Abstract: A circuit device is provided in which the bonding reliability of a brazing material such as soft solder is improved. A circuit device of the present invention includes conductive patterns, a bonding material which fixes circuit elements to the conductive patterns, and sealing resin which covers the circuit elements. The circuit device has a structure in which Pb-free solder containing Bi is used as the bonding material. Since the melting temperature of Bi is high in comparison with that of a general solder, the melting of the bonding material is suppressed when the circuit device is mounted. Further, Ag or the like may be mixed into the bonding material in order to enhance the wettability of the bonding material.

Abstract: A displacement sensor includes a plurality of conductive members, a semiconductor device, and a nonmagnetic conductor electrically connecting one of the conductive members and one of a low electric potential side and a high electric potential side of a power supply of the semiconductor device. The conductive member is electrically connected with the semiconductor device through a nonmagnetic conductor.

Abstract: In a liquid level sensing apparatus, a rotating part is fixed with an arm. The arm is arranged to rotate in accordance with a liquid level. The rotating part is supported rotatably on a bearing portion of a housing. A magnet is housed in the rotating part. A magnetoelectric transducer element fixed to the housing is arranged to perform a magnetic detection to convert an intensity of a magnetic field produced by the magnet to an electric signal. The rotating part is formed with an exposure hole exposing a surface of the magnet. The exposed surface of the magnet is located out of a magnetic circuit subjected to the magnetic detection of the magnetoelectric transducer element.

Abstract: In a liquid level sensing apparatus, a rotating part is fixed with an arm. The arm is arranged to rotate in accordance with a liquid level. The rotating part is supported rotatably on a bearing portion of a housing. A magnet is housed in the rotating part. A magnetoelectric transducer element fixed to the housing is arranged to perform a magnetic detection to convert an intensity of a magnetic field produced by the magnet to an electric signal. The rotating part is formed with an exposure hole exposing a surface of the magnet. The exposed surface of the magnet is located out of a magnetic circuit subjected to the magnetic detection of the magnetoelectric transducer element.

Abstract: A rotation angle sensor includes a rotatable magnet, at least one yoke located at a position to confront a magnetic pole, and a magnetic sensing device to sense magnetic flux density varying in accordance with a confronting area between the yoke and the magnet. The yoke is electrically connected with the magnetic sensing device through a nonmagnetic conductor.

Abstract: A circuit device is provided in which the bonding reliability of a brazing material such as soft solder is improved. A circuit device of the present invention includes conductive patterns, a bonding material which fixes circuit elements to the conductive patterns, and sealing resin which covers the circuit elements. The circuit device has a structure in which Pb-free solder containing Bi is used as the bonding material. Since the melting temperature of Bi is high in comparison with that of a general solder, the melting of the bonding material is suppressed when the circuit device is mounted. Further, Ag or the like may be mixed into the bonding material in order to enhance the wettability of the bonding material.

Abstract: A rotation angle sensor including a magnet rotatable about an axis, a first and second yokes arranged around said magnet and diametrically opposed to each other, and a Hall effect device disposed between the first and second yokes. The yokes include arcuately curved pole piece portions radially opposed to the magnet and overhang portions extending angularly inwardly from the pole piece portions across the axis of the magnet, respectively. The overhang portions have a generally sector shape and cooperate to define a gap therebetween within which the Hall effect device is disposed. Leakage flux reducing members circumferentially extends between the pole piece portions.

Abstract: A rotation angle sensor including a magnet rotatable about an axis, a first and second yokes arranged around said magnet and diametrically opposed to each other, and a Hall effect device disposed between the first and second yokes. The yokes include arcuately curved pole piece portions radially opposed to the magnet and overhang portions extending angularly inwardly from the pole piece portions across the axis of the magnet, respectively. The overhang portions have a generally sector shape and cooperate to define a gap therebetween within which the Hall effect device is disposed. Leakage flux reducing members circumferentially extends between the pole piece portions.

Abstract: A rotation angle sensor including a magnet rotatable about an axis, a first and second yokes arranged around said magnet and diametrically opposed to each other, and a Hall effect device disposed between the first and second yokes. The yokes include arcuately curved pole piece portions radially opposed to the magnet and overhang portions extending angularly inwardly from the pole piece portions across the axis of the magnet, respectively. The overhang portions have a generally sector shape and cooperate to define a gap therebetween within which the Hall effect device is disposed. Leakage flux reducing members circumferentially extend between the pole piece portions.

Abstract: A rotation angle sensor is provided, including a casing, and a magnet positioned in the casing. The magnet has a first magnetic pole end and a second magnetic pole end. First and second yokes are positioned at a first predetermined space relative to the first magnetic pole end of the magnet, and a third yoke is positioned at a predetermined space relative to the second magnetic pole end of the magnet. The third yoke is further positioned between the magnet and an extending portion of the first yoke, and is also positioned between the magnet and an extending portion of the second yoke. A first signal output element, which is positioned between the third yoke and the extended portion of the first yoke, outputs a first signal corresponding to an area ratio between the magnet and the first yoke. A second signal output element, which is positioned between the third yoke and the extended portion of the second yoke, outputs a second signal corresponding to an area ratio between the magnet and the second yoke.