GMR or TMR sensor used with a ferromagnetic encoder

1. A speed sensor arrangement, implemented as a wheel rotation speed sensor arrangement, comprising

a sensor and a ferromagnetic encoder,

wherein the sensor has at least one magnetic field sensor element and a signal processing circuit, the speed sensor arrangement having a permanent magnet and wherein the magnetic field provided by said permanent magnet is modulated by the ferromagnetic encoder at least during a movement of the encoder and the magnetic field sensor element of the sensor detects this modulated magnetic field,

wherein the magnetic field sensor element is implemented as a GMR sensor element or as a TMR sensor element and the speed sensor arrangement is implemented such that the permanent magnet is arranged at a defined minimum distance from the magnetic field sensor element, and

wherein the defined minimum distance is greater than a length or a width of the magnetic field sensor element.

2. The speed sensor arrangement as claimed in claim 1 , wherein the ferromagnetic encoder is implemented substantially as a gear wheel or a perforated disc.

3. The speed sensor arrangement as claimed in claim 1 , wherein the permanent magnet is arranged separately from the sensor and has a separate mounting.

4. The speed sensor arrangement as claimed in claim 3 , wherein said mounting comprises a retaining element, having a rod-shaped design, made of plastic and/or fiberglass or non-magnetic metal.

5. The speed sensor arrangement as claimed in claim 3 , wherein the speed sensor arrangement is designed such that the permanent magnet and the sensor are arranged on two different and/or opposite sides of the encoder.

6. The speed sensor arrangement as claimed in claim 5 , wherein the permanent magnet, which is arranged on the opposite side of the lead frame, is arranged separately and/or spaced apart from the lead frame and/or the magnetic field sensor element by a part of the plastic housing and/or a spacer embedded in the plastic housing, implemented in plastic.

7. The speed sensor arrangement as claimed in claim 1 , wherein the permanent magnet is mounted on the sensor directly or indirectly by a coupling element or the sensor is mounted on the coupling element, in the same way as the permanent magnet mounted separately on the coupling element.

8. The speed sensor arrangement as claimed in claim 7 , wherein the coupling element is implemented such that it encompasses the encoder at a distance and wherein the sensor and the magnet are arranged on two different and/or opposite sides of the encoder, the coupling element having a fork-shaped and/or C-shaped and/or pincer-shaped design.

9. The speed sensor arrangement as claimed in claim 1 , wherein the permanent magnet is integrated into the sensor, the sensor consisting of a plastic housing in which the permanent magnet is arranged or on which the permanent magnet is arranged.

10. The speed sensor arrangement as claimed in claim 9 , wherein the sensor has a lead frame on which the magnetic field sensor element is arranged, wherein the permanent magnet is arranged on the opposite side of the lead frame, spaced apart from the lead frame by a part of the plastic housing.

11. The speed sensor arrangement as claimed in claim 10 , wherein the permanent magnet, which is arranged on the opposite side of the lead frame, is arranged separately and/or spaced apart from the lead frame and/or the magnetic field sensor element by a part of the plastic housing and/or a spacer embedded in the plastic housing, implemented in plastic.

12. The speed sensor arrangement as claimed in claim 9 , wherein the permanent magnet is completely embedded in the plastic housing of the sensor.

13. The speed sensor arrangement as claimed in claim 9 , wherein the permanent magnet is at least partially received by the spacer and/or held thereby so as to enclose it, clipped into said spacer, and the spacer with the permanent magnet are jointly embedded in the plastic housing of the sensor.

14. The speed sensor arrangement as claimed in claim 13 , wherein the magnetic field sensor element and the signal processing circuit are integrated on a chip and the spacer receives or additionally encompasses the chip, and wherein the sensor does not have a lead frame.

15. A use of the speed sensor arrangement as claimed in claim 1 as a wheel rotation speed sensor arrangement in a motorcycle and/or in a single-track motor vehicle and/or in a two-wheeled motor vehicle.

16. The speed sensor arrangement as claimed in claim 1 , wherein the ferromagnetic encoder is positioned between the permanent magnet and the magnetic field sensor element.