초록 ▼

A brake system for motor vehicles of “brake-by-wire” type without a brake booster, having a hydraulic activation device which can be activated by means of a brake pedal and to which wheel brakes are connected, and a simulation device which can be activated hydraulically and has at least one elastic

A brake system for motor vehicles of “brake-by-wire” type without a brake booster, having a hydraulic activation device which can be activated by means of a brake pedal and to which wheel brakes are connected, and a simulation device which can be activated hydraulically and has at least one elastic element which gives the driver of a vehicle a pleasant pedal sensation is intended to have a functional capacity which can be checked during the normal braking function and to give the driver a pedal sensation which is familiar from a conventional hydraulic brake system. For this purpose, the activation device is connected via a hydraulic connection to the simulation device, wherein the hydraulic connection is connected via an electrically controllable check valve to a pressure medium reservoir which is at atmospheric pressure.

대표청구항 ▼

1. A brake system of a brake-by-wire type for motor vehicles, comprising a hydraulic actuation device that can be actuated by means of a brake pedal, to which actuation device are connected a plurality of wheel brakes, and having a hydraulically actuated simulation device having at least an elastic

1. A brake system of a brake-by-wire type for motor vehicles, comprising a hydraulic actuation device that can be actuated by means of a brake pedal, to which actuation device are connected a plurality of wheel brakes, and having a hydraulically actuated simulation device having at least an elastic element that conveys to the vehicle driver a comfortable pedal sensation, the actuation device connected by way of a hydraulic connection to the simulation device, wherein the hydraulic connection is connected by way of an electrically controllable shut-off valve to a pressure medium container that is subjected to atmospheric pressure wherein the simulation device is only connected with the brake pedal after the shut-off valve is closed. 2. The brake system as claimed in claim 1, wherein the shut-off valve is in the form of a normally open electrically controllable valve. 3. The brake system as claimed in claim 1, wherein the actuation device further comprises a pressure chamber for pressure medium that is conveyed into the hydraulic connection as the brake pedal is actuated. 4. The brake system as claimed in claim 1, wherein the actuation device further comprises a travel sensor for sensing an actuation travel of the brake pedal. 5. The brake system as claimed in claim 1, wherein the brake system further comprises an electrically controllable pressure supplying device. 6. The brake system as claimed in claim 5, wherein the pressure supplying device is provided in the form of a cylinder-piston arrangement, the piston of which can be actuated by means of an electromechanical actuator. 7. The brake system as claimed in claim 1, wherein outside of a brake-by-wire operating mode and in a fall-back operating mode, the simulation device is switched to a no-pressure state, where the entire pressure medium is available for braking the vehicle. 8. The brake system as claimed in claim 1, wherein the electrically controllable shut-off valve is operated based upon a degree of actuation displacement of the brake pedal. 9. The brake system as claimed in claim 1, wherein as the brake pedal is actuated in a brake-by-wire operating mode, the shut-off valve is switched into a closed switch position if the actuating travel of the brake pedal exceeds a predetermined limit value. 10. A method for operating a brake system for motor vehicles comprising; providing a hydraulic actuation device that can be actuated by means of a brake pedal, to which actuation device are connected a plurality of wheel brakes, and having a hydraulically actuated simulation device having at least an elastic element that conveys to the vehicle driver a comfortable pedal sensation, the actuation device connected by way of a hydraulic connection to the simulation device, wherein the hydraulic connection is connected by way of an electrically controllable shut-off valve to a pressure medium container that is subjected to atmospheric pressure, in that as brake pedal is actuated and when the system is in a brake-by-wire operating mode, switching the shut-off valve into a closed switch position if the actuating travel of the brake pedal exceeds a predetermined limit value. 11. The method as claimed in claim 10 further comprising setting the predetermined limit value in dependence upon the driving situation. 12. A brake system of a brake-by-wire type for motor vehicles, comprising a hydraulic actuation device that can be actuated by means of a brake pedal, to which actuation device are connected a plurality of wheel brakes, and having a hydraulically actuated simulation device having at least an elastic element that conveys to the vehicle driver a comfortable pedal sensation, the actuation device connected by way of a hydraulic connection to the simulation device, wherein the hydraulic connection is connected by way of an electrically controllable shut-off valve to a pressure medium container that is subjected to atmospheric pressure, wherein the hydraulic connection includes a first line section that extends from the actuation device, the first line section branching into a second line section that connects to the simulation device and into a third line section that connects to the pressure medium container; wherein the simulation device is enabled and fluid flows into the simulation device through the second line section when the shut-off valve is in a closed position. 13. The brake system as claimed in claim 12, wherein the shut-off valve is connected into the third line section.