US 12,235,134 B2
Sensor for a magnetic measuring device
Martin Joerg, Wertach (DE); Mathias Kimmerle, Steinheim (DE); and Peter Bigl, Fischen (DE)
Assigned to Robert Bosch GmbH, Stuttgart (DE)
Appl. No. 17/600,446
Filed by Robert Bosch GmbH, Stuttgart (DE)
PCT Filed Mar. 24, 2020, PCT No. PCT/EP2020/058202
§ 371(c)(1), (2) Date Sep. 30, 2021,
PCT Pub. No. WO2020/207788, PCT Pub. Date Oct. 15, 2020.
Claims priority of application No. 10 2019 205 193.6 (DE), filed on Apr. 11, 2019.
Prior Publication US 2022/0196436 A1, Jun. 23, 2022
Int. Cl. G01D 5/14 (2006.01); G01B 7/14 (2006.01); G01B 7/30 (2006.01); G01P 3/44 (2006.01)
CPC G01D 5/145 (2013.01) [G01B 7/14 (2013.01); G01B 7/30 (2013.01); G01P 3/44 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A sensor for a magnetic measuring device for detecting a rotational or translational movement of a shaft, comprising:
a permanent magnet connected in a rotationally fixed manner to the shaft so as to move together with the shaft, the permanent magnet including a plastic bonded permanent magnetic material injection molded onto the shaft as an extension of the shaft that forms a free end of the shaft; and
a fixing geometry of the shaft including a protruding structure with a mushroom-shaped protrusion cross section and a surrounding protrusion undercut,
wherein the protruding structure protrudes directly from the shaft,
wherein the permanent magnet completely encloses the protruding structure, such that a radial and axial positive engagement is formed between the permanent magnet and the shaft,
wherein the shaft is cylindrical and defines a first diameter and a rotational axis,
wherein the permanent magnet defines a cylindrical portion having a second diameter that is equal to the first diameter at an intersection of the cylindrical portion with the shaft,
wherein the first diameter of the cylindrical portion is constant in a direction extending away from the shaft along the rotational axis,
wherein the permanent magnet defines a tapered portion extending from the cylindrical portion opposite the intersection of the cylindrical portion with the shaft along the rotational axis,
wherein the tapered portion has a plurality of diameters that decrease in size in the direction extending away from the shaft along the rotational axis,
wherein the permanent magnet defines a front surface that intersects the tapered portion, the front surface being circular and flat, and the front surface defining a distal end of the permanent magnet, and
wherein a third diameter of the front surface is substantially equal to a smallest diameter of the plurality of diameters of the tapered portion.