BRAKE CYLINDER ARRANGEMENT AND BRAKING SYSTEM

Abstract

A brake cylinder arrangement has a brake cylinder, a pressure sensor, and a pressure reducer, wherein the pressure reducer transfers pressures from the brake cylinder to the pressure sensor differently, depending on the input pressure range. The invention furthermore relates to a braking system having a brake cylinder arrangement of this kind.

Claims

1. A brake cylinder arrangement comprising: a brake cylinder; a pressure sensor connected to the brake cylinder to sense a pressure in the brake cylinder; a pressure reducer which passes the pressure from the brake cylinder to the pressure sensor with a first modification factor in a first input pressure range, which extends from 0 bar to a predetermined pressure threshold and when the pressure exceeds the pressure threshold, passes the pressure from the brake cylinder to the pressure sensor with a second modification factor; and wherein the pressure transferred at the pressure threshold is in a second input pressure range, which includes pressures greater than the predetermined pressure threshold.

2. The brake cylinder arrangement as claimed in claim 1, wherein the predetermined pressure threshold is between 60 bar and 80 bar or a value of 70 bar.

3. The brake cylinder arrangement as claimed in claim 1, wherein the first modification factor has a value of 1.

4. The brake cylinder arrangement as claimed in claim 1, wherein the second modification factor has a value of less than 1.

5. The brake cylinder arrangement as claimed in claim 1, wherein the pressure reducer is a hydraulic pressure reducer.

6. The brake cylinder arrangement as claimed in claim 1, wherein the brake cylinder is a brake master cylinder of a motor vehicle.

7. The brake cylinder arrangement as claimed in claim 1, wherein the pressure sensor is configured to trigger a burst protection function when the pressure reaches a predetermined safety threshold.

8. The brake cylinder arrangement as claimed in claim 7, wherein the safety threshold corresponds to an input pressure of the pressure reducer of between 260 bar and 280 bar.

9. A braking system for a motor vehicle, comprising: a brake cylinder arrangement including; a brake cylinder; a pressure sensor connected to the brake cylinder to sense a pressure in the brake cylinder; a pressure reducer which passes the pressure from the brake cylinder to the pressure sensor with a first modification factor in a first input pressure range, which extends from 0 bar to a predetermined pressure threshold and when the pressure exceeds the pressure threshold, passes the pressure from the brake cylinder to the pressure sensor with a second modification factor; and wherein the pressure transferred at the pressure threshold is in a second input pressure range, which includes pressures greater than the predetermined pressure threshold; and a plurality of brakes, which are connected to the brake cylinder of the brake cylinder arrangement.

10. The braking system as claimed in claim 9, wherein the predetermined pressure threshold is between 60 bar and 80 bar or a value of 70 bar.

11. The braking system as claimed in claim 9, wherein the first modification factor has a value of 1.

12. The braking system as claimed in claim 9, wherein the second modification factor has a value of less than 1.

13. The braking system as claimed in claim 9, wherein the pressure reducer is a hydraulic pressure reducer.

14. The braking system as claimed in claim 9, wherein the brake cylinder is a brake master cylinder of a motor vehicle.

15. The braking system as claimed in claim 9, wherein the pressure sensor is configured to trigger a burst protection function when the pressure reaches a predetermined safety threshold.

16. The braking system as claimed in claim 15, wherein the safety threshold corresponds to an input pressure of the pressure reducer of between 260 bar and 280 bar.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein:

[0020] FIG. 1 shows a braking system according to the invention, and

[0021] FIG. 2 shows a transfer characteristic of the pressure reducer illustrated in FIG. 1.

DETAILED DESCRIPTION

[0022] FIG. 1 shows a braking system 1 according to an exemplary embodiment of the invention. The braking system 1 has a brake cylinder arrangement 5, a brake pedal 15 and a number of brakes 40. It should be understood that these components are illustrated here only schematically in a block diagram.

[0023] The brake cylinder arrangement 5 has a brake cylinder 10, which is connected to the brake pedal 15. It is thereby possible for a driver to produce a pressure in the brake cylinder 10 by actuating the brake pedal 15. In this way, the brakes 40 can be actuated.

[0024] The brake cylinder arrangement 5 furthermore has a pressure reducer 20 and a pressure sensor 30. As shown, the pressure sensor 30 is connected to the brake cylinder 10 via the pressure reducer 20.

[0025] The pressure reducer 20 has the transfer characteristic illustrated in FIG. 2. Here, the input pressure p.sub.i is plotted on the horizontal axis, and the output pressure p.sub.a is plotted on the vertical axis.

[0026] The input pressure p.sub.i is thus the pressure prevailing in the brake cylinder 10. The output pressure p.sub.a is the pressure which is transferred to the pressure sensor 30.

[0027] As shown, pressure transfer by the pressure reducer 20 is initially unchanged up to a predetermined pressure threshold p.sub.s, i.e. a first modification factor of 1 is applied. In other words, the input pressure p.sub.i is equal to the output pressure p.sub.a.

[0028] Above the predetermined pressure threshold p.sub.s, however, the illustrated curve is shallower, i.e. a second modification factor less than 1 is used. The output pressure p.sub.a is thus attenuated in comparison with the input pressure p.sub.i. It should be understood that the pressure attained at the predetermined pressure threshold p.sub.s serves as a reference, i.e. the pressure component of the input pressure p.sub.i that exceeds the pressure threshold p.sub.s is multiplied by the second modification factor and added to the output pressure p.sub.a at the pressure threshold.

[0029] In the present case, the predetermined pressure threshold ps is 70 bar, wherein the maximum pressure to be expected in the brake cylinder is about 270 bar. The illustrated transfer characteristic of the pressure reducer 20 makes it possible to use a pressure sensor 30 which does not have to be designed for a pressure up to 270 bar but can have a lower measurement range. This makes the choice of pressure sensor 30 considerably easier.

[0030] It should further be pointed out that refinements, features and variants which are described in the various embodiments or exemplary embodiments and/or shown in the figures can be combined with one another in any desired manner. Single or multiple features may be interchanged with one another in any desired manner. Combinations of features arising therefrom are intended to be understood to be covered by the disclosure of this application as well.

[0031] The foregoing preferred embodiments have been shown and described for the purposes of illustrating the structural and functional principles of the present invention, as well as illustrating the methods of employing the preferred embodiments and are subject to change without departing from such principles. Therefore, this invention includes all modifications encompassed within the scope of the following claims.