Brake system for a utility vehicle, utility vehicle, and method for operating the brake system

A utility vehicle, comprising:

• a brake system, including:
• an electronic brake controller unit;
• a pneumatic parking brake circuit, including:
• at least one spring energy cylinder;
• a parking brake valve to control a parking brake pressure in the parking brake circuit;
• and
• at least one 3/3-way valve, which is arranged in a pneumatic line of the parking brake circuit, between the parking brake valve and at least one of the spring energy cylinders, wherein the 3/3-way valve is actuable by the electronic brake controller unit;
• wherein the 3/3-way valve is configured to ventilate the pneumatic line between the 3/3-way valve and at least one of the spring energy cylinders to a predefined pressure, so as to cause the at least one of the spring energy cylinders to allow a brake, which is assigned to the spring energy cylinder, to pass into engagement;
• wherein the electronic control unit is configured to detect a failure of a function of a service brake circuit in the utility vehicle, and based on the detecting of the failure, actuate the at least one 3/3-way valve to ventilate the pneumatic line between the at least one 3/3-way valve and the spring energy cylinder to the predefined pressure, so as to allow the at least one brake which is assigned to the at least one spring energy cylinder to pass into engagement.

A method for operating a brake system of a utility vehicle, the method comprising:

• releasing at least one brake, which is assigned to at least one spring energy cylinder by actuating a parking brake valve and increasing a parking brake pressure in a parking brake circuit, wherein the brake system includes:
• an electronic brake controller unit;
• a pneumatic parking brake circuit, including:
• the at least one spring energy cylinder;
• the parking brake valve to control the parking brake pressure in the parking brake circuit;
• and
• at least one 3/3-way valve, which is arranged in a pneumatic line of the parking brake circuit, between the parking brake valve and at least one of the spring energy cylinders, wherein the 3/3-way valve is actuable by the electronic brake controller unit;
• wherein the 3/3-way valve is configured to ventilate the pneumatic line between the 3/3-way valve and at least one of the spring energy cylinders to a predefined pressure, so as to cause the at least one of the spring energy cylinders to allow the brake, which is assigned to the spring energy cylinder, to pass into engagement;
• detecting, by the electronic brake controller unit, a failure of a function of a service brake circuit of the utility vehicle;
• and
• based on the detecting of the failure of the function of the service brake circuit, actuating, by the electronic brake controller unit, the at least one 3/3-way valve and ventilating of the pneumatic line between the at least one 3/3-way valve and the spring energy cylinder to a predefined pressure, so as to allow the at least one brake which is assigned to the at least one spring energy cylinder to pass into engagement.