Railway axle bearing and sealing assembly with integrated rotational speed detector

A railway axle assembly comprising:

• a fixed support member;
• a rotating member coaxially arranged in the fixed support member;
• a rolling bearing housed in a seat defined between the fixed member and the rotating member to rotatably support the rotating member with respect to the fixed member;
• a sealing assembly provided adjacent to the rolling bearing on an outer side of the seat facing a seat closure cover thereof;
• said sealing assembly comprising a first annular rigid screen connected to said rotating member and a second annular rigid screen connected with said fixed member, said sealing assembly further comprising a spacer ring coaxially mounted on said rotating member and an axial locking element carried fixedly by said rotating member for urging said spacer ring against an inner ring of said rolling bearing fixed to said rotating member;
• said first screen being C-shaped in radial section and mounted with its concavity facing towards said cover in such a manner as to be clamped between the spacer ring and said the ring of the rolling bearing;
• said second screen being defined by a concave annular element fixed to an outer ring of the rolling bearing rigid with said fixed member and having its concavity facing the concavity of the first screen, said screens being partly inter-fitted within one another in such a way as to define therebetween a labyrinth seal and, together with said rings of the rolling bearing, a sealed chamber closed in a fluid-tight manner by said labyrinth seal;
• and,
• a detector sensitive to the speed of rotation of the rotating member, said detector comprising a sector secured to the fixed member and an annular member rotating relative to the sensor, said annular member encoded with a plurality of zones of discontinuity having substantially the same width and disposed circumferentially at substantially constant pitch, said discontinuity zones being designed to transit past the sensor for activating the sensor to generate a periodic signal having a frequency proportional to the number of said zones which transit past the sensor in a selected unit time wherein said annular encoded member is part of the first annular rigid screen of said sealing assembly, while said sensor is carried in a fixed manner by the second annular rigid screen of said sealing assembly and said annular encoded member and said sensor are housed inside said sealed chamber radially spaced from each other.