Hub unit for driving wheel

1. A hub unit for a driving wheel in which:

one track ring out of a stationary ring and a rotary ring is an outer ring having a plurality of outer ring tracks on the inner peripheral surface thereof;

the other track ring of the stationary ring and the rotary ring is an inner ring assembly comprising a shaft member and inner ring as a separate body combined with each other and having a plurality of inner ring tracks on the outer peripheral surface thereof;

the shaft member is formed with one of the inner ring tracks in a middle part in the axial direction thereof and a small-diameter step portion having a smaller diameter than that of the inner ring track portion at an end portion in the axial direction thereof; and

said separate inner ring has the other of the inner ring tracks on the outer peripheral surface thereof and is fitted on said small-diameter step portion;

the hub unit comprising:

a sensor holder fixed to the stationary ring of the hub unit for a driving wheel;

a sensor supported by said sensor holder and facing an encoder fixed to said rotary ring to rotate together with said rotary ring; and

a harness or connector extended out of said sensor for taking out a detection signal of the sensor,

wherein the sensor holder includes an annular metal portion and a resin portion formed integrally therewith, the annular metal portion having integrally a portion fixedly fitted to said stationary ring an annular portion radially inwardly extended from the fixedly fitted portion and an end portion extended axially from a radially inner end of the annular portion over an inner diameter portion of said resin portion, said resin portion being integrally formed with said radially extended annular portion and said axially extended end portion;

the sensor that is annular, is fixed to the resin portion of the sensor holder with a plurality of screws spaced apart circumferentially from each other;

the sensor unit includes said sensor and said harness or connector;

all of the portions of said sensor unit provided outside the outer ring in the axial direction and inside a range of a hub unit mounting hole of a knuckle are disposed on the inner side in the radial direction than an inner wall of the hub unit mounting hole of the knuckle;

said harness or connector is disposed on the outer side in the radial direction in a non-contact manner with a constant velocity universal joint in a finished car;

said sensor is an active sensor;

a sensing portion of said sensor directly faces said encoder without interposition between it and said encoder; and

said harness or connector is extended out of a gap between said knuckle and said constant velocity universal joint.

2. A hub unit for a driving wheel according to claim 1 , wherein the sensor is formed with a plurality of concaved holes each for receiving the head of the screw.