Brake pressure modulator and use of a brake pressure modulator

A brake pressure modulator (110;

• 106), comprising:
• a relay valve (202) for controlling a supply of pressurized air from a primary source (II) to at least one brake actuator (112a, 112b);
• a first valve sub-unit (204) configured to be electronically actuated, wherein the first valve sub-unit (204) is configured to receive a primary control pressure from the primary source (II) intended for operating the relay valve (202);
• and
• a second valve unit (206) configured to at least receive a secondary control pressure from a secondary source (‘BST’) and at least part of the primary control pressure from the primary source (II) and to transmit either the primary control pressure or the secondary control pressure to the relay valve (202), and wherein, when the secondary control pressure is transmitted to the relay valve (202) from the second valve unit (206), the primary control pressure from the primary source (II) is disconnected, and when the primary control pressure is transmitted to the relay valve (202) from the second valve unit (206), the secondary control pressure from the secondary source is disconnected, and wherein the second valve unit (206) is a mechanically operable valve,
• wherein said mechanically operable valve is a double-sided check valve (206) that selectively transmits the pressure of a higher magnitude among the primary control pressure and secondary control pressure received from the primary source (II) and the secondary source (BST), respectively, to the relay valve (202) and
• wherein the first valve sub-unit (204) includes at least two solenoid controlled valves (208, 210), wherein an outlet (208.2) of a first one (208) of the at least two solenoid controlled valves (208, 210) leads to an inlet (206.1) of said double-sided check valve (206) and also to an inlet (210.1) of a second one (210) of the at least two solenoid controlled valves (208, 210);
• wherein the first valve sub-unit (204) includes first and second solenoid controlled 2/2 direction control valves (208, 210) and wherein, based on an actuation state of each of the first and second solenoid controlled 2/2 direction control valves, the brake pressure modulator (110;
• 106) performs at least one of the following functions:
• enabling the supply of the primary control pressure from the primary source (II) to actuate the relay valve (202);
• disabling or blocking the supply of the primary control pressure from the primary source (II) to the relay valve (202);
• and/or
• releasing the primary control pressure from the primary source (II) to the atmosphere, wherein the primary control pressure is intended for operating the relay valve (202);
• wherein a spatial arrangement or spatial requirement of each of the two solenoid controlled 2/2 direction control valves (208, 210) within the brake pressure modulator (110;
• 106) is the same as a spatial arrangement or spatial requirement of the double-sided check valve (206).