Patent ID: 6945698

Claim:
A shaft speed monitor comprising: a hub with a bearing bore, a hub bearing end, a hub open end, a first bearing positioning stop extending radially inward from the bearing bore, a second bearing positioning stop extending radially inward from the bearing bore, a cylindrical seal counter bore extending axially inward from the hub open end and concentric with the bearing bore, and a grommet passage extending radially through the hub between the hub open end and the second bearing positioning stop, and a mounting flange integral with the hub; a bearing mounted in the bearing bore between the first bearing positioning stop and the second bearing positioning stop and wherein the bearing is axially fixed in the bearing bore by the first bearing positioning stop and the second bearing positioning stop; a spindle having an inboard end, an outboard end, a bearing mounting surface adjacent to the inboard end, a cylindrical toothed ring mounting surface coaxially with the bearing mounting surface and between the bearing mounting surface and the outboard end, and a cylindrical sealing surface between the toothed ring mounting surface and the outboard end, and wherein the bearing mounting surface is received in the bearing thereby holding the spindle in a position coaxial with the bearing bore and rotatable relative to the hub; a toothed ring mounted on the toothed ring mounting surface and rotatably fixed relative to the spindle; a coil pack assembly including a ring magnet embedded in a bobbin, a coil groove in the bobbin and axially spaced from the ring magnet, a coil winding in the coil groove, and wherein the coil pack assembly is mounted in the hub between the second bearing position stop and the cylindrical counter bore with the ring magnet in radial alignment with the toothed ring; a seal mounted in the cylindrical seal counter bore in the hub and in sealing engagement with the cylindrical sealing surface on the spindle; a grommet mounted in the grommet passage through the hub; and leads extending through the grommet and connected to the coil winding in the bobbin.