Abstract: A coil assembly for a solenoid valve includes a bobbin formed from an electrically insulative material. A bore extends axially through the bobbin. A first flux ring having a sleeve extending axially from an annular base is mounted upon a first end of the bobbin with the sleeve extending into the bobbin bore. Similarly, a second flux ring also having a sleeve extending from an annular base is mounted upon a second end of the bobbin that is opposite from the first flux ring with its sleeve extending into the bobbin bore. The flux rings are formed from a magnetically permeable material that has a high heat conductivity. Magnet wire is wound upon the assembled bobbin and flux rings to form the coil assembly.

Abstract: A control valve for controlling fluid flow in a hydraulic control unit of a vehicular brake system includes a valve seat. A sleeve is mounted on the valve seat. An armature core is slidably received in the sleeve. The sleeve includes a first ferromagnetic portion adjacent the valve seat, a second ferromagnetic portion, and an annular region defining an area of increased magnetic reluctance. A part of the first portion of the sleeve defines a radial magnetic pole for the generally radial flow of magnetic flux from the armature to the sleeve. A portion of the valve seat adjacent the armature defines an axial magnetic pole for the generally axial flow of magnetic flux from the armature to the valve seat. Together, the generally radial flow of flux and the generally axial flow of flux generate a force urging the armature from an open position toward a closed position when the coil is energized.

Abstract: An improved structure for an electrical actuation mechanism adapted for use in a disc brake assembly includes an electrical actuation mechanism adapted to be secured to an inboard leg of the caliper of the disc brake assembly. The electrical actuation mechanism includes a housing, an electrical motor disposed in the housing, and a spindle disposed in the housing and operatively coupled to the motor by a conversion gear assembly which is effective to convert rotary motion generated by the motor into axial movement of the piston. The spindle includes a shaft and a piston which can be coupled to the shaft by a dampening structure. The shaft is operatively connected to the motor for axial motion thereof, and the piston is operatively connected to a friction pad for engaging a rotor attached to a wheel of a vehicle in which the disc brake assembly is installed. The dampening structure can be comprised of elastomeric material or a fluid filled chamber defined between the piston and the shaft.

Abstract: A hydraulic control unit for a vehicle anti-lock brake system is disclosed which comprises a bore defining a chamber symmetrical about an axis and having a sidewall and a bottom wall. A fluid inlet passage is open to the bore from one of the walls and a damping orifice of substantially restricted diameter relative to the inlet passage is in open communication with the inlet passage. An attenuator is seated within the chamber and is sealed relative to the chamber to preclude the flow of brake fluid from the control unit. The attenuator includes a compressibly deformable solid core member that substantially fills the chamber.