Abstract: A system for simulating brake feel for a vehicle braking installation comprising a hydraulic braking system (7, 8) and an electric braking system (9). This system comprises a first chamber (20) containing a force transmitting fluid (21) and in which there slides a hydraulic piston (22) under the control of a manual braking operating member (1), the first chamber (20) communicating with a second, secondary simulation chamber (4) via a simulation valve (3), the degree of opening of which allows a force to be simulated at the brake pedal.

Abstract: A vehicle braking assembly comprising a master cylinder (10) with no central valves, a brake fluid reservoir (62) mounted separately from the master cylinder (10), pumps (50) for pressurizing the brake fluid and first solenoid valves (68) in pipes (66) connecting the brake fluid reservoir (62) to the inlets of the pumps (50). According to the invention, a calibrated orifice (76) and a nonreturn valve (78) which are connected in parallel are mounted in these pipes (66).

Abstract: A vehicle braking assembly comprising a master cylinder (10) with no central valves, a brake fluid reservoir (62) mounted separately from the master cylinder (10), pumps (50) for pressurizing the brake fluid and first solenoid valves (68) in pipes (66) connecting the brake fluid reservoir (62) to the inlets of the pumps (50). According to the invention, a calibrated orifice (76) and a nonreturn valve (78) which are connected in parallel are mounted in these pipes (66).

Abstract: The invention relates to a system for simulating brake feel for a vehicle braking installation comprising a hydraulic braking system (7, 8) and an electric braking system (9). This system comprises a first chamber (20) containing a force transmitting fluid (21) and in which there slides a hydraulic piston (22) under the control of a manual braking operating member (1), said first chamber (20) communicating with a second, secondary simulation chamber (4) via a simulation valve (3), the degree of opening of which allows a force to be simulated at the brake pedal.

Abstract: Motor vehicle braking installation comprising a master cylinder (10) operated by a brake pedal and connected to a brake fluid reservoir (30) and to feed circuits (26, 28) supplying the wheel brakes, characterized in that the brake fluid reservoir (30) is mounted on the master cylinder and is connected to the master cylinder (10) by connecting means (32, 34) involving electrically operated valves (36, 38) which valves are closed in the rest position and are made to open by a computer (C) on the basis of an output signal from a position sensor or displacement transducer (40) associated with the brake pedal or with the said element moved by this pedal.

Abstract: A braking device for a motor vehicle having a first brake circuit (10) with a master cylinder (11) controlled by a brake pedal (12), a second brake circuit (20) with at least one pump (27) that is controlled by a computer (C), and a pedal travel simulation mechanism (40). The simulation mechanism (40) includes a solenoid valve (41) that is mounted in a pipe (42) connected to a hydraulic fluid storage chamber (43) and controlled by the computer (C) so as to allow the brake fluid to flow toward the chamber (43) when the second brake circuit (20) is active and when the driver presses on the brake pedal. The pipe (42) is also connected to another pipe (44) in which hydraulic fluid is displaced by a first part (45) of a control rod connected to the brake pedal (12) and second part (46) associated with the master cylinder (11).

Abstract: A braking device for a motor vehicle having a first brake circuit (10) with a master cylinder (11) controlled by a brake pedal (12), a second brake circuit (20) with at least one pump (27) that is controlled by a computer (C), and a pedal travel simulation mechanism (40). The simulation mechanism (40) includes a solenoid valve (41) that is mounted in a pipe (42) connected to a hydraulic fluid storage chamber (43) and controlled by the computer (C) so as to allow the brake fluid to flow toward the chamber (43) when the second brake circuit (20) is active and when the driver presses on the brake pedal. The pipe (42) is also connected to another pipe (44) in which hydraulic fluid is displaced by a first part (45) of a control rod connected to the brake pedal (12) and second part (46) associated with the master cylinder (11).

Abstract: A pneumatic-hydraulic hybrid pneumatic brake booster is improved. Additional hydraulic boosting (19, 20) provided by a hydraulic circuit is provided beyond a saturation point (Psat) in the operation of the pneumatic circuit. Hysteresis-induced instabilities in the pneumatic part of the booster are taken into consideration (50). A choice is made to compensate (A) for the shortfall in operation of the pneumatic circuit using the hydraulic circuit. In one example, this correction is afforded via a microprocessor which imposes a corrected process signal. Using this signal, pressure shifts in the pneumatic system are neutralized.

Abstract: The invention relates to a process and a device for determining the instantaneous value of the amplification provided by a pneumatic-assistance servomotor (14) in a braking device for a motor vehicle, wherein instantaneous values of the relative vacuum level inside the negative-pressure chamber (24) of the servomotor and of the hydraulic pressure at the exit from the master cylinder (16) are measured using sensors (28 and 30), and wherein output signals provided by said sensors are processed by data-processing means (32) so as to compute a pressure difference (?P), proportional to the instantaneous amplification provided by the servomotor and, if required, an instantaneous value of the pressure (Prc) inside the working chamber (26) of the servomotor.

Abstract: The invention relates to a process and a device for determining the instantaneous value of the amplification provided by a pneumatic-assistance servomotor (14) in a braking device for a motor vehicle, wherein instantaneous values of the relative vacuum level inside the negative-pressure chamber (24) of the servomotor and of the hydraulic pressure at the exit from the master cylinder (16) are measured using sensors (28 and 30), and wherein output signals provided by said sensors are processed by data-processing means (32) so as to compute a pressure difference (&Dgr;P), proportional to the instantaneous amplification provided by the servomotor and, if required, an instantaneous value of the pressure (Prc) inside the working chamber (26) of the servomotor.

Abstract: Pneumatic brake-booster with additional hydraulic boosting and method for boosting braking using such a booster.