Hitachi, Ltd.

Syouichi Kawamata

Hiroshi Kimura

Fumio Tajima

Kunio Miyashita

Osamu Koizumi

Toshihiko Fukushima

Rumi Minakata

Mitsuo Kudoh

Suetato Shibukawa

A rotating motor is provided which permits heat to be efficiently dissipated from all of the stator, rotor, and inner and outer races of bearings. This assures that the rotor exhibits a high intensity as it turns. Also, long bearing life is assured. A coolant enters a cooling passage formed in a first end bracket from entrance pipes and makes a half revolution, thus cooling a first one of the bearings. Also, the coolant cools the rotor via cooling disks and rotor disks. Then, the coolant flows into an outer surface-cooling passage in a motor housing and takes a zigzag course so as to make a substantially half revolution, thus cooling the stator. The coolant then flows into a cooling passage in a second end bracket and makes one revolution, thus cooling a second bearing. At the same time, the rotor is cooled via the cooling disks and rotor disks. Subsequently, the coolant enters another outer surface-cooling passage and makes a substantially half revolution, thus cooling the stator. The coolant then flows into another cooling passage in the aforementioned first end bracket and makes a substantially half revolution, thus cooling the first bearing again. Also, the rotor is cooled via the cooling disks and rotor disks.

Rotating motor and motor-driven vehicle

A magnetic recording medium is provided on a rotary drum and is divided into a plurality of magnetic tracks. On each track is recorded a magnetic signal of a combination of a magnetization portion which consists of two consecutive unit magnets (pitch .lambda.) and a no-magnetization portion having the same length (2.lambda.) that are alternatingly arranged over the whole periphery of the track. First magnetoresistive elements in the magnetic sensor are arranged in pairs so as to be opposed to the magnetic tracks maintaining a distance of .lambda./2. Second magnetoresistive elements opposed to the magnetic track that correponds to the lowest-order bit of position detecting signals, are arranged in a number of ##EQU1## for the first magnetoresistive element maintaining a distance of ##EQU2## wherein SM.sub.L denotes the length of the magnetic signal of the magnetic track, m denotes the number of the increased bits (0&lt;m.ltoreq.2), and n denotes an integer (0.ltoreq.n&lt;2). Thus, detecting signals are obtained in a bit number in excess of the number of the magnetic tracks.

Magnetic position detector for detecting an absolute position of a

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Hitachi, Japan

Syouichi Kawamata