US 12,123,750 B2
Rotation detection device
Kazuhiko Tomita, Tokyo (JP)
Assigned to Proterial, Ltd., Tokyo (JP)
Filed by Hitachi Metals, Ltd., Tokyo (JP)
Filed on Feb. 4, 2021, as Appl. No. 17/167,898.
Claims priority of application No. 2020-019854 (JP), filed on Feb. 7, 2020.
Prior Publication US 2021/0247208 A1, Aug. 12, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. G01D 5/14 (2006.01)
CPC G01D 5/145 (2013.01) 7 Claims
OG exemplary drawing
 
1. A rotation detection device, comprising:
a detection target member formed in an annular shape that is attached to a rotating member and comprises a plurality of magnetic poles along a circumferential direction about a rotational axis of the rotating member, and
a sensor unit that is attached to a stationary member not rotating with rotation of the rotating member and is arranged to face the detection target member,
wherein the sensor unit comprises a magnetic sensor and a housing portion covering the magnetic sensor,
wherein the magnetic sensor comprises a plate-shaped detection portion comprising a magnetic detection element to detect a magnetic field from the detection target member and a plurality of connection terminals extending out of the detection portion,
wherein the magnetic detection element comprises a magnetoresistive effect element to detect a magnetic field in a direction perpendicular to a plate thickness direction of the detection portion,
wherein the sensor unit is positioned such that a fore-end portion of the detection portion of the magnetic sensor faces toward an axial end face of the detection target member, the fore-end portion being an end portion located opposite to the side where the plurality of connection terminals extend out,
wherein the detection portion is arranged adjacent to the detection target member as viewed from a direction of the rotational axis,
wherein the plurality of connection terminals align in a direction crossing a radial direction of the detection target member, and are extending out from the detection portion in the direction of the rotational axis from an axial end face-side,
wherein the housing portion comprises a facing portion that faces the detection target member and a thickness of the facing portion is thinner than a radial width of the detection target member,
wherein the housing portion comprises a holder holding the magnetic sensor and a resin mold portion covering around the holder, and
wherein the housing portion is configured such that a portion facing the fore-end portion of the detection portion comprises only the holder and the detection portion is covered by the resin mold portion except for the fore-end portion.