Hitachi Metals, Ltd.

Yukimasa Shonowaki

Osamu Shimoe

Yasunori Abe

Hitoshi Harata

Hiromitsu Itabashi

Hiroyuki Mima

Takehiko Sagara

Michiyuki Fukushima

Katsutoshi Hiratsu

To provide a bearing sensor having a thin plane coil for applying a biasing magnetic field and at least one magneto resistive element pair (a first magneto resistive thin plate and a second magneto resistive thin plate) crossing opposed conductor sides of the coil. The plane coil has at least one pair of opposed conductor sides (a first side and a second side). The first magneto resistive thin plate and the first side cross one another at an angle more than 30 degrees and less than 90 degrees. The second magneto resistive thin plate and the second side cross one another at an angle more than 30 degrees and less than 90 degrees. While biasing magnetic fields in opposite directions are applied to the magneto resistive thin plates, respectively, intermediate potentials of the magneto resistive element pair are measured to determine bearings based on the difference between the intermediate potentials.

Bearing sensor having magneto resistive elements

A magnetic encoder containing a magnetic drum having on its side surface a plurality of magnetic signal-generating means having different magnetic pole pitches, and a plurality of magnetoresistance elements each disposed opposite to each of the magnetic signal-generating means. The magneto resistance elements include a plurality of series-connected thin, ferromagnetic layer patterns having a magnetoresistance effect so that an output signal of each magnetoresistance element is in the form of a substantially sinusoidal curve. The magnetic pole pitch of one magnetic signal-generating means is 5 times or more the magnetic pole pitch of other magnetic signal-generating means, and the magnetoresistance element opposite to the magnetic signal-generating means having a larger magnetic pole pitch includes by 5 or more series-connected thin, ferromagnetic layer patterns within the range of one-fourth the larger magnetic pole pitch.

Magnetic encoder with a plurality of magnetic signal-generating means

A magnetic sensor has first, second, third and fourth magneto-resistance effect elements disposed in a direction of a magnetizing pitch (1) of a magnetic recording medium serving to supply a magnetic signal, with first and second magneto-resistance effect elements disposed spacedly from each other at an interval corresponding to an electrical angle of .theta., the third and fourth magneto-resistance effect elements disposed spacedly from each other at an interval corresponding to an electrical angle of (360.degree.-.theta.), and the intervals between the center line of the first and second magneto-resistance effect elements and between the line of the third and fourth magneto-resistance effect elements being set to n.lambda.. The four magneto-resistance effect elements are connected to one another in series in the order of the first, second, fourth and third magneto-resistance effect elements with both ends of the serially-connected magneto-resistance effect elements being provided with a power source terminal, and an output terminal being provided at a conjunctive point of the second and fourth magneto-resistance effect elements. .theta. is set to a range of 30.degree..ltoreq..theta..ltoreq.90.degree., based on .lambda.=360 to thereby enable an output wave form of the magnetic sensor to have a large or sharp gradient in the vicinity of a comparing level.

Magnetic sensor having spaced magneto-resistance elements

Growing community of inventors

Kumagaya, Japan

Yukimasa Shonowaki