| 摘要 |
In a railway axle 1 of the type in which a rolling element bearing 6 is mounted within a seat 5 defined between two members, a first of which (e.g. a shaft 3) rotates with respect to the second (support 2) and provided, externally of the seat, with a sealing assembly 12 adapted to protect the bearing, an annular element 15 of the sealing assembly is fixed for rotation with the rotating member 3 and is provided with a sensor ring 30 having a plurality of permanently magnetised zones of substantially the same width and circumferentially spaced from one another with substantially constant pitch, and within the seat and close to the said annular element 15 there is further provided a sensor 31 carried by the fixed member 2 and activated by the said magnetised zones to generate a periodic signal having a frequency proportional to the number of zones which pass the sensor in unit time. The ring 30 may be of filled rubber or plastics, or made by sintering, and it may be an integral part of the seal element 15. The sensor 31 is of Hall or magneto-resistive type. The magnetised zones may be of alternating polarity, or of the same polarity and separated by inactive zones. The sensor is stated to produce a useful signal at low speeds. <IMAGE> |
