Rotational angle sensor

Patent metadata

Field	Value
Publication number	US-10845216-B2
Application number	US-201716079795-A
Country	US
Kind code	B2
Filing date	Feb 24, 2017
Priority date	Feb 24, 2016
Publication date	Nov 24, 2020
Grant date	Nov 24, 2020

Abstract

A rotational angle sensor includes a stator element and rotor element. The stator element has a stator transmitting coil, circuit board, and at least two identically configured stator receiving coils angularly offset from each other on the circuit board. The rotor element is mounted rotatably about a rotation axis relative to the stator element, and has a rotor receiving coil and rotor transmitting coil electrically connected to each other. The rotor receiving coil is inductively coupled to the stator transmitting coil such that an electromagnetic field produced by the stator transmitting coil induces a current in the rotor receiving coil that flows through the rotor transmitting coil and causes the rotor transmitting coil produces a further electromagnetic field. The stator receiving coils are inductively coupled to the rotor transmitting coil in a manner configured with reference to a rotational angle between the stator element and the rotor element so that the further electromagnetic field induces at least two angle-dependent alternating voltages in the stator receiving coils. Each stator receiving coil is formed from a plurality of radial conductors and circumferential conductors that are arranged in two levels of the circuit board such that, for each stator receiving coil, at least two oppositely directed partial windings are formed from the radial conductors circumferential conductors. The radial conductors extend radially from an inner end to an outer end and are arranged on the circuit board in sets of two at least partially overlapping conductors with opposite current directions. Each circumferential conductor extends circumferentially, connects two inner ends or two outer ends of respective radial conductors, and has a via providing a change between the levels of the circuit board.

First claim

The invention claimed is:

1. A rotational angle sensor, comprising:
a stator element including:
a stator transmitting coil;
a printed circuit board having a first plane and a second plane; and
at least two identically configured stator receiving coils that are angularly offset with respect to each other, and that are arranged on the printed circuit board, wherein:
each of the at least two stator receiving coils is formed from a respective plurality of radial conductors and a respective plurality of circumferential conductors that are arranged in the two planes of the circuit board such that at least two oppositely directed partial windings are formed per stator receiving coil from the respective plurality of radial conductors and the respective plurality of circumferential conductors;
the plurality of radial conductors each extend in a radial direction from an inner end to an outer end, and are arranged on the printed circuit board in sets of two radial conductors with opposite current directions, the two radial conductors in each of the sets being arranged in a different one of the two planes; and
each of the plurality of circumferential conductors extends in a circumferential direction, and connects two inner ends or two outer ends of two of the radial conductors, and has a respective plated-through hole at which the circumferential conductor changes between the planes of the printed circuit board; and

a rotor element mounted rotatably about an axis of rotation with respect to the stator element, and including a rotor receiving coil and a rotor transmitting coil that are electrically connected to each other;
wherein the rotor receiving coil is inductively coupled to the stator transmitting coil such that an electromagnetic field generated by the stator transmitting coil induces a current in the rotor receiving coil that flows through the rotor transmitting coil and causes the rotor transmitting coil to generate a further electromagnetic field; and
wherein the at least two stator receiving coils are inductively coupled to the rotor transmitting coil such that the inductive coupling between the at least two stator receiving coils and the rotor transmitting coil is configured with reference to a rotational angle between the stator element and the rotor element, and such that the further electromagnetic field generated by the rotor transmitting coil induces at least two angle-dependent AC voltages in the at least two stator receiving coils.

2. The rotational angle sensor as claimed in claim 1 , wherein each of the plurality of circumferential conductors is curved arcuately between the respective plated-through hole and at least one end of the circumferential conductor.

3. The rotational angle sensor as claimed in claim 1 , wherein the stator transmitting coil and the at least two stator receiving coils are arranged together in the two planes of the printed circuit board.

4. The rotational angle sensor as claimed in claim 1 , wherein the plated-through hole of each of the plurality of circumferential conductors is arranged in a center between two outer ends or inner ends of the respective radial conductors.

5. The rotational angle sensor as claimed in claim 1 , wherein at least one of:
the plated-through holes of the circumferential conductors connecting the inner ends of the radial conductors lie radially further inward than the respective inner ends;
the plated-through holes of the circumferential conductors connecting the outer ends of the radial conductors lie radially further outward than the respective outer ends;
the plated-through holes of the circumferential conductors connecting the inner ends of the radial conductors are arranged at a location of the respective circumferential conductor with a minimum distance with respect to an axis of symmetry; and
the plated-through holes of the circumferential conductors connecting the outer ends of the radial conductors are arranged at a location of the respective circumferential conductor with a maximum distance with respect to an axis of symmetry.

6. The rotational angle sensor as claimed in claim 1 , wherein at least one of:
the inner ends of the plurality of radial conductors are all at an identical distance with respect to an axis of symmetry; and
the outer ends of the plurality of radial conductors are all at an identical distance from an axis of symmetry.

7. The rotational angle sensor as claimed in claim 1 , wherein:
a first plated-through hole is arranged at an end of a first circumferential conductor of the plurality of circumferential conductors, the first circumferential conductor being arranged in the first plane; and
the first plated-through hole connects the first circumferential conductor to an end of a first radial conductor of the plurality of radial conductors, the first radial conductor being arranged in the second plane.

8. The rotational angle sensor as claimed in claim 7 , wherein:
a second plated-through hole is located at an end of a second circumferential conductor, the second circumferential conductor being arranged in the first plane, and connects the end of the first circumferential conductor to a second radial conductor, the second radial conductor being arranged on the second plane; and
the second plated-through hole is arranged symmetrically with respect to a further plated-through hole located at an end of another circumferential conductor.

9. The rotational angle sensor as claimed in claim 1 , wherein the rotor transmitting coil is formed from at least two partial windings which are oriented in opposite directions.

10. The rotational angle sensor as claimed in claim 9 , wherein the at least two partial windings of the rotor transmitting coil are configured in a sickle-shaped fashion.

Assignees

• Bosch Gmbh Robert

Inventors

• Utermoehlen Fabian
• Merz Andreas

Classifications

• G01D5/2073 Primary

  by movement of a single coil with respect to two or more coils · CPC title