Coolant control valve

A coolant control system for a vehicle, the coolant control system comprising a fluid actuated coolant control valve, a coolant source, and a heat exchanger of a Diesel Emission Fluid (DEF) tank, wherein the fluid actuated coolant control valve comprises:

• a valve housing;
• an inlet port defined within the valve housing, the inlet port configured for fluid communication with one of the coolant source or the heat exchanger of the DEF an outlet port defined within the valve housing, the outlet port configured for fluid communication with the other one of the heat exchanger of the DEF tank or the coolant source;
• a valve chamber fluidly connecting the inlet port and the outlet port;
• a movable valve member;
• an actuator configured to actuate the movable valve member, wherein the actuator comprises a fluid actuated piston coupled to the movable valve member and disposed in a piston chamber within the actuator;
• a pilot port configured to receive actuation pneumatic fluid to move the fluid actuated piston and the movable valve member coupled thereto;
• a vent tube, separate from the pilot port, and configured to vent coolant weeping to the piston chamber from the valve chamber to an external environment of the fluid actuated coolant control valve;
• and
• a lid configured to close an open end of the valve housing to define the piston chamber, wherein the lid is disposed at least partially external to the valve housing, and wherein the lid comprises the vent tube such that the vent tube is disposed external to the valve housing and an orientation of the vent tube is independent of the valve housing,
• wherein the movable valve member is biased by a biasing element to a valve closed condition in which a flow of coolant from the inlet port to the outlet port is prevented by the movable valve member in the valve chamber, and
• wherein the movable valve member is actuatable, when the actuation pneumatic fluid moves the fluid actuated piston coupled to the movable valve member, to a valve open condition in which the flow of coolant from the inlet port to the outlet port is permitted and the movable valve member is withdrawn from the valve chamber.

A Diesel Emission Fluid (DEF) system for a diesel-powered vehicle having a coolant control valve, the coolant control valve comprising:

• a valve housing;
• an inlet port defined within the valve housing, the inlet port configured for fluid communication with one of a coolant source or a heat exchanger of a DEF tank;
• an outlet port defined within the valve housing, the outlet port configured for fluid communication with the other one of the heat exchanger of the DEF tank or the coolant source;
• a valve chamber fluidly connecting the inlet port and the outlet port;
• a movable valve member;
• an actuator configured to actuate the movable valve member, wherein the actuator comprises a fluid actuated piston coupled to the movable valve member and disposed in a piston chamber within the actuator;
• a pilot port configured to receive actuation pneumatic fluid to move the fluid actuated piston and the movable valve member coupled thereto;
• a vent tube, separate from the pilot port, and configured to vent coolant weeping to the piston chamber from the valve chamber to an external environment of the coolant control valve;
• and
• a lid configured to close an open end of the valve housing to define the piston chamber, wherein the lid is disposed at least partially external to the valve housing, and wherein the lid comprises the vent tube such that the vent tube is disposed external to the valve housing and an orientation of the vent tube is independent of the valve housing,
• wherein the movable valve member is biased by a biasing element to a valve closed condition in which a flow of coolant from the inlet port to the outlet port is prevented by the movable valve member in the valve chamber, and
• wherein the movable valve member is actuatable, when the actuation pneumatic fluid moves the fluid actuated piston coupled to the movable valve member, to a valve open condition in which the flow of coolant from the inlet port to the outlet port is permitted and the movable valve member is withdrawn from the valve chamber.

A vehicle having a Diesel Emission Fluid (DEF) system, the DEF system having a coolant control valve comprising:

• a valve housing;
• an inlet port defined within the valve housing, the inlet port configured for fluid communication with one of a coolant source or a heat exchanger of a DEF tank;
• an outlet port defined within the valve housing, the outlet port configured for fluid communication with the other one of the heat exchanger of the DEF tank or the coolant source;
• a valve chamber fluidly connecting the inlet port and the outlet port;
• a movable valve member;
• an actuator configured to actuate the movable valve member, wherein the actuator comprises a fluid actuated piston coupled to the movable valve member and disposed in a piston chamber within the actuator;
• a pilot port configured to receive actuation pneumatic fluid to move the fluid actuated piston and the movable valve member coupled thereto;
• a vent tube, separate from the pilot port, and configured to vent coolant weeping to the piston chamber from the valve chamber to an external environment of the coolant control valve;
• and
• a lid configured to close an open end of the valve housing to define the piston chamber, wherein the lid is disposed at least partially external to the valve housing, and wherein the lid comprises the vent tube such that the vent tube is disposed external to the valve housing, and an orientation of the vent tube is independent of the valve housing,
• wherein the movable valve member is biased by a biasing element to a valve closed condition in which a flow of coolant from the inlet port to the outlet port is prevented by the movable valve member in the valve chamber, and
• wherein the movable valve member is actuatable, when the actuation pneumatic fluid moves the fluid actuated piston coupled to the movable valve member, to a valve open condition in which the flow of coolant from the inlet port to the outlet port is permitted and the movable valve member is withdrawn from the valve chamber.