Abstract: A check valve assembly is designed for insertion in an existing fuel tank filler tube having a mechanical nozzle seal and a vapor recirculation port. The insert has an integrally formed ground strap/tab for grounding a refueling nozzle and an attached flexible flapper positioned adjacent the recirculation port by an integrally formed spring tab. The insert has friction tabs for engaging the inner surface of the filler tube for retaining the check valve assembly in the filler tube.

Abstract: An improved method of estimating a vehicle speed reference value (VREF) at a wheel so as to prevent false slip detection and premature ABS activation in a motor vehicle equipped with an Anti-Locking Braking System. A maximum possible rate of change of velocity (ACCEL limit) for the vehicle is determined over a predetermined range of corresponding vehicle speeds. Wheel speed and estimated reference speed at the wheel (VREF) are determined along with the rate of change of the wheel speed (WHEEL ACCEL). The WHEEL ACCEL is compared to the corresponding ACCEL limit to limit the estimated reference speed to the corresponding ACCEL limit.

Abstract: A reduced brake switch dependence (RBSD) control method and system for a vehicle anti-lock brake system (ABS) having a brake switch. The control method includes generating a RBSD control signal when the brake switch is inoperative, and performing RBSD control of the ABS in response to the RBSD control signal. The control system includes wheel speed sensors, ABS control valves, and a programmable microprocessor ABS control unit for performing the control method.

Abstract: A method and system are disclosed for controlling an anti-lock brake system based on vehicle deceleration. The system includes a wheel speed sensor and control unit for performing the method steps of sensing a wheel speed and determining a wheel deceleration and a vehicle deceleration therefrom. The control unit also performs the method steps of determining an initial deceleration threshold representing a pre-lockup condition, determining a final deceleration threshold based on the vehicle deceleration, comparing the wheel deceleration to the final deceleration threshold, and activating the vehicle anti-lock brake system if the wheel deceleration exceeds the final deceleration threshold.

Abstract: A method is provided for modifying anti-lock brake control to a vehicle braking on a surface having a split-mu to higher-mu transition. The time duration of the apply stage of an anti-lock brake system cycle is measured for the two front wheels. The measured apply stage durations are compared to a selected threshold. The transition from the split-mu surface to the higher-mu surface is detected when the apply stage duration for the lower-mu wheel exceeds the selected threshold. An increased brake pressure rate is applied to both front wheels when the split-mu to high-mu transition is detected.

Abstract: A system is provided for modifying anti-lock brake control to a vehicle braking on a surface having a split-mu to higher-mu transition. The time duration of the apply stage of an anti-lock brake system cycle is measured for the two front wheels. The measured apply stage durations are compared to a selected threshold. The transition from the split-mu surface to the higher-mu surface is detected when the apply stage duration for the lower-mu wheel exceeds the selected threshold. An increased brake pressure rate is applied to both front wheels when the split-mu to high-mu transition is detected.