Rotary valve for single-point coolant diversion in engine cooling system

An engine cooling system for a vehicle, said cooling system distributing heat from an engine using a coolant, said cooling system comprising:

• a pump for circulating said coolant;
• an engine circuit for conducting said coolant through said engine;
• a radiator circuit for conducting said coolant through a radiator;
• a bypass circuit for returning said coolant to said engine circuit without passing through said radiator circuit;
• a heater circuit for conducting said coolant through a heater core;
• a rotary valve for single-point coolant switching of said coolant, said rotary valve comprising:
• a valve body having an inlet port and a plurality of outlet ports, said outlet ports including a radiator port for allowing coolant flow in said radiator circuit, a bypass port for allowing coolant flow in said bypass circuit, and a heater port for allowing coolant flow in said heater circuit;
• a flow diverter rotationally received in said valve body and including a plurality of fluid passages providing predetermined flow paths between said inlet port and said outlet ports in response to a rotational position of said flow diverter;
• and
• an actuator responsive to a control signal for setting said rotational position;
• wherein said predetermined flow paths include a first mode for distributing said coolant to said radiator port and said heater port while blocking coolant from said bypass port, a second mode for distributing said coolant to said bypass port while blocking coolant from said radiator port and said heater port, a third mode for distributing said coolant to said heater port while blocking coolant from said radiator port and said bypass port, and a fourth mode for distributing said coolant to said radiator port and said bypass port while blocking coolant from said heater port;
• and
• wherein said first mode corresponds to a failsafe position for said flow diverter if said actuator fails, said rotary valve further comprising a return mechanism for biasing said flow diverter to said failsafe position;
• and
• a controller responsive to predetermined vehicle parameters for generating said control signal to select one of said modes in response to said predetermined vehicle parameters.

A rotary valve for single-point coolant switching of coolant flowing in an engine cooling system, comprising:

• a valve body having an inlet port and a plurality of outlet ports, said outlet ports including a radiator port for allowing coolant flow in a radiator circuit and a bypass port for allowing coolant flow in a bypass circuit;
• a flow diverter rotationally received in said valve body and including a plurality of fluid passages providing predetermined flow paths between said inlet port and said outlet ports in response to a rotational position of said flow diverter;
• and
• an actuator responsive to a control signal for setting said rotational position;
• wherein said fluid passages provide a first range of said rotational positions of said flow diverter in a first mode of said rotary valve for distributing said coolant from said inlet port to said bypass port while blocking coolant distribution to said radiator port and provide a second range of said rotational positions of said flow diverter in a second mode of said rotary valve for distributing said coolant from said inlet port to both said bypass port and said radiator port, and wherein at least one selected one of said fluid passages and said bypass outlet have a variable overlapping cross-sectional area between said first and second modes to provide a plurality of selectable flow rates to said bypass port including at least a first flow rate in said first mode and a second flow rate higher than said first flow rate in said second mode, wherein said first flow rate provides increased heat flow into said coolant.

An engine cooling system for a vehicle, said cooling system distributing heat from an engine using a coolant, said cooling system comprising:

• a pump for circulating said coolant;
• an engine circuit for conducting said coolant through said engine;
• a radiator circuit for conducting said coolant through a radiator;
• a bypass circuit for returning said coolant to said engine circuit without passing through said radiator circuit;
• a rotary valve for single-point coolant switching of said coolant, said rotary valve comprising:
• a valve body having an inlet port and a plurality of outlet ports, said outlet ports including a radiator port for allowing coolant flow in said radiator circuit and a bypass port for allowing coolant flow in said bypass circuit;
• a flow diverter rotationally received in said valve body and including a plurality of fluid passages providing predetermined flow paths between said inlet port and said outlet ports in response to a rotational position of said flow diverter;
• and
• an actuator responsive to a control signal for setting said rotational position;
• wherein said fluid passages provide a first range of said rotational positions of said flow diverter in a first mode of said rotary valve for distributing said coolant from said inlet port to said bypass port while blocking coolant distribution to said radiator port and provide a second range of said rotational positions of said flow diverter in a second mode of said rotary valve for distributing said coolant from said inlet port to both said bypass port and said radiator port, and wherein at least one selected one of said fluid passages and said bypass outlet have a variable overlapping cross-sectional area between said first and second modes to provide a plurality of selectable flow rates to said bypass port including at least a first flow rate in said first mode and a second flow rate higher than said first flow rate in said second mode, wherein said first flow rate provides increased heat flow into said coolant;
• and
• a controller responsive to predetermined vehicle parameters for generating said control signal to select one of said modes in response to said predetermined vehicle parameters.

A method of circulating coolant in a cooling system for an internal combustion engine, said cooling system including a pump for circulating said coolant, an engine circuit for conducting said coolant through said engine, a radiator circuit for conducting said coolant through a radiator, and a bypass circuit for returning said coolant to said engine circuit without passing through said radiator circuit, said method comprising the steps of:

• starting said engine;
• circulating said coolant through said bypass circuit at a first rate and substantially preventing circulation through said radiator circuit during an initial period;
• and
• circulating said coolant through said bypass circuit at a second rate while circulating said coolant through said radiator circuit during a subsequent period, wherein said second rate is greater than said first rate and said first rate provides increased heat flow into said coolant from said engine.

A rotary valve for single-point coolant switching of coolant flowing in an engine cooling system, comprising:

• a valve body having an inlet port and a plurality of outlet ports, said outlet ports including a radiator port for allowing coolant flow in a radiator circuit, a bypass port for allowing coolant flow in a bypass circuit, and a heater port for allowing coolant flow in a heater circuit;
• a flow diverter rotationally received in said valve body and including a plurality of fluid passages providing predetermined flow paths between said inlet port and said outlet ports in response to a rotational position of said flow diverter;
• and
• an actuator responsive to a control signal for setting said rotational position;
• wherein said predetermined flow paths include a first mode for distributing said coolant to said radiator port and said heater port while blocking coolant from said bypass port, a second mode for distributing said coolant to said bypass port while blocking coolant from said radiator port and said heater port, a third mode for distributing said coolant to said heater port while blocking coolant from said radiator port and said bypass port, and a fourth mode for distributing said coolant to said radiator port and said bypass port while blocking coolant from said heater port;
• wherein a flow rate of coolant distributed to an outlet port in at least one of said modes is proportional to a variable overlapping cross-sectional area of a respective fluid passage and said outlet port;
• and
• wherein a flow rate to said bypass port in said fourth mode is greater than a flow rate to said bypass port in said second mode to provide greater heat flow into said coolant in said second mode.

An engine cooling system for a vehicle, said cooling system distributing heat from an engine using a coolant, said cooling system comprising:

• a pump for circulating said coolant;
• an engine circuit for conducting said coolant through said engine;
• a radiator circuit for conducting said coolant through a radiator;
• a bypass circuit for returning said coolant to said engine circuit without passing through said radiator circuit;
• a heater circuit for conducting said coolant through a heater core;
• a rotary valve for single-point coolant switching of said coolant, said rotary valve comprising:
• a valve body having an inlet port and a plurality of outlet ports, said outlet ports including a radiator port for allowing coolant flow in said radiator circuit, a bypass port for allowing coolant flow in said bypass circuit, and a heater port for allowing coolant flow in said heater circuit;
• a flow diverter rotationally received in said valve body and including a plurality of fluid passages providing predetermined flow paths between said inlet port and said outlet ports in response to a rotational position of said flow diverter;
• and
• an actuator responsive to a control signal for setting said rotational position;
• wherein said predetermined flow paths include a first mode for distributing said coolant to said radiator port and said heater port while blocking coolant from said bypass port, a second mode for distributing said coolant to said bypass port while blocking coolant from said radiator port and said heater port, a third mode for distributing said coolant to said heater port while blocking coolant from said radiator port and said bypass port, and a fourth mode for distributing said coolant to said radiator port and said bypass port while blocking coolant from said heater port;
• wherein a flow rate of coolant distributed to an outlet port in at least one of said modes is proportional to a variable overlapping cross-sectional area of a respective fluid passage and said outlet port;
• and
• wherein a flow rate to said bypass port in said fourth mode is greater than a flow rate to said bypass port in said second mode to provide greater heat flow into said coolant in said second mode;
• and
• a controller responsive to predetermined vehicle parameters for generating said control signal to select one of said modes in response to said predetermined vehicle parameters.

A rotary valve for single-point coolant switching of coolant flowing in an engine cooling system, comprising:

• a valve body having an inlet port and a plurality of outlet ports, said outlet ports including a radiator port for allowing coolant flow in a radiator circuit, a bypass port for allowing coolant flow in a bypass circuit, and a heater port for allowing coolant flow in a heater circuit;
• a flow diverter rotationally received in said valve body and including a plurality of fluid passages providing predetermined flow paths between said inlet port and said outlet ports in response to a rotational position of said flow diverter;
• and
• an actuator responsive to a control signal for setting said rotational position;
• wherein said predetermined flow paths include a first mode for distributing said coolant to said radiator port and said heater port while blocking coolant from said bypass port, a second mode for distributing said coolant to said bypass port while blocking coolant from said radiator port and said heater port, a third mode for distributing said coolant to said heater port while blocking coolant from said radiator port and said bypass port, and a fourth mode for distributing said coolant to said radiator port and said bypass port while blocking coolant from said heater port;
• and
• wherein a flow rate of coolant distributed to each outlet port in each of said modes is proportional to a variable overlapping cross-sectional area of a respective fluid passage and each respective outlet port, at least one of said fluid passages having an outlet profile such that its respective overlapping cross sectional area with a respective outlet port changes at a rate unequal to a rate at which an overlapping cross sectional area of a different fluid passage and a different outlet port simultaneously change, whereby flow rates provided to different output ports are independently controlled.