TECHNICAL FIELD

This disclosure relates to a system for cooling a driveline retarder coupled to an internal combustion engine.

BACKGROUND

Vehicles propelled by internal combustion engines generally include cooling systems having an external circuit that allows engine coolant to flow through a vehicle radiator to manage the heat loads of the engine. Certain vehicles, such as large or heavy duty vehicles are fitted with driveline retarders. The driveline retarder is used to assist with braking and slowing the vehicle and in this implementation produce a significant amount of heat. The driveline retarder typically includes a heat exchanger to dissipate the heat generated during operation and thereby maintain the driveline retarder at a safe operating temperature. Vehicles equipped with a driveline retarder generally include a coolant circuit where the engine coolant is routed through the heat exchanger of the driveline retarder and then on to the vehicle radiator and internal combustion engine. While this coolant circuit may dissipate the coolant heat loads of the engine and of the driveline retarder, the added restriction of the driveline retarder heat exchanger and negatively impacts the cooling capability of the vehicle. While water pump speeds may be increased to compensate for the increased coolant system restrictions, increased water pump speeds lead to increased water pump parasitics that result in reduced engine efficiency.

SUMMARY

Various embodiments provide systems and methods of controlling coolant flow. Various embodiments provide a coolant diverter system that includes a coolant diverter body having a coolant inlet opening, a driveline retarder outlet opening and a bypass outlet opening. The coolant diverter system also includes a valve positioned in the coolant diverter body. The valve is configured in a first valve orientation to fluidly couple the coolant inlet opening to the driveline retarder outlet opening in isolation from the bypass outlet opening. The valve is configured in a second valve orientation to fluidly couple the coolant inlet opening to the driveline retarder outlet opening and the bypass outlet opening. The coolant diverter system also includes a valve controller configured to place the valve in the first valve orientation in response to activation of a driveline retarder coupled to the driveline retarder outlet opening for braking.

In particular embodiments, the valve controller is further configured to place the valve in the second valve orientation in response to deactivation of the driveline retarder. The valve controller may be further configured to place the valve in the second valve orientation in response to deactivation of the driveline retarder and in response to a temperature in the driveline retarder being below a predetermined threshold. In particular embodiments, the valve controller is further configured to place the valve in the first valve orientation in response to an indication of a temperature in a driveline retarder coupled to the retarder outlet opening being above a predetermined threshold and to place the valve in the second valve orientation in response to the temperature in the driveline retarder being below the predetermined threshold. The diverter body further includes a retarder inlet opening fluidly coupled to the bypass outlet opening, in accordance with particular embodiments. The diverter body further includes a coolant outlet opening, in accordance with particular embodiment. The valve may include a pop-valve. The valve may include a throttle-valve. In particular embodiments, the valve is configured to in a third valve orientation fluidly couple the coolant inlet opening to the bypass outlet opening in isolation from the retarder outlet opening.

Various embodiments provide a valve control system that includes a driveline retarder condition module configured to generate an activation signal in response to activation of a driveline retarder. The system also includes a valve control module coupled to the driveline retarder condition module. The valve control module is configured to generate a first valve control command in response to receipt of the activation command. The first valve control command is configured to cause a valve positioned in a valve diverter body to move to a first valve orientation fluidly coupling a coolant inlet opening in the valve diverter body to a driveline retarder outlet opening in the valve diverter body in isolation from the bypass outlet opening. The valve moves to the first valve orientation from a second valve orientation. The second valve orientation fluidly couples the coolant inlet opening to the driveline retarder outlet opening and a bypass outlet opening in the valve diverter body.

Various embodiments provide a valve control system that includes a driveline retarder condition module and a valve control module coupled to the driveline retarder condition module. The driveline retarder condition module is structured to determine that a driveline retarder in a vehicle is in one of an activated state and a deactivated state responsive to at least one of received temperature data and vehicle operation data, the temperature data indicative of a temperature of the driveline retarder and the vehicle operation data indicative of an operating condition of the vehicle. The valve control module is structured to generate one of a first valve control command and a second valve control command responsive to a determined state of the driveline retarder. The first valve control command is generated in response to a determined activated state. The first valve control command is configured to cause a valve positioned in a valve diverter body to move to a first valve orientation fluidly coupling a coolant inlet opening in the valve diverter body to a driveline retarder outlet opening in the valve diverter body in isolation from the bypass outlet opening. The second valve control command is generated in response to a determined deactivated state. The second valve command is configured to cause the valve to move to a second valve orientation, the second valve orientation fluidly coupling the coolant inlet opening to the driveline retarder outlet opening and a bypass outlet opening in the valve diverter body.

Various embodiments provide a method of controlling coolant flow to a driveline retarder. The method includes determining activation of a driveline retarder. The method also includes causing a valve positioned in a coolant diverter body to move to a first valve orientation fluidly coupling a coolant inlet opening in the valve diverter body to a driveline retarder outlet opening in the valve diverter body in isolation from the bypass outlet opening in response to activation of the driveline retarder. The valve moves to the first valve orientation from a second valve orientation. The second valve orientation fluidly couples the coolant inlet opening to the driveline retarder outlet opening and a bypass outlet opening in the valve diverter body.

Various embodiments provide an engine system that includes an internal combustion engine including a driveline component. The engine system also includes a driveline retarder coupled to the driveline component for applying braking force to the driveline component. The engine system includes a coolant circulation system coupled to the internal combustion engine. The engine system includes a coolant diverter body fluidly coupling the coolant circulation system to the driveline retarder. The coolant diverter body has a coolant inlet opening in fluid communication with the coolant circulation system, a driveline retarder outlet opening in fluid communication with a coolant inlet opening, a bypass passage outlet opening in fluid communication with the coolant inlet opening, and a coolant outlet opening in fluid communication with a driveline retarder coolant inlet opening the bypass passage outlet opening, and the coolant circulation system. The engine system also includes a valve positioned in the diverter body. The valve is configured in a first valve orientation to fluidly isolate the bypass passage outlet opening from the coolant inlet opening. The valve is further configured to in a second valve orientation to fluidly couple the coolant inlet opening to the driveline retarder outlet opening and the bypass passage outlet opening. The engine system also includes a valve controller configured to move the valve from the second valve orientation to the first valve orientation in response to activation of a driveline retarder coupled to the driveline retarder outlet opening for braking.

Further embodiments provide a coolant diverter system. The system includes a coolant diverter body having a coolant inlet opening, a driveline retarder outlet opening and a bypass outlet opening. A valve is positioned in the coolant diverter body. The valve is configured, in a first valve orientation, to fluidly couple the coolant inlet opening to the driveline retarder outlet opening in isolation from the bypass outlet opening. The valve is configured, in a second valve orientation, to fluidly couple the coolant inlet opening to the driveline retarder outlet opening and the bypass outlet opening. A valve controller is configured to receive operation data regarding the driveline retarder and selectively place the valve in one of the first and second valve orientations responsive to the operation data.

Still further embodiments also provide a method of controlling coolant flow to a driveline retarder. The method includes receiving operation data regarding a driveline retarder. The method further includes causing a valve positioned in a coolant diverter body to move to a first valve orientation fluidly coupling a coolant inlet opening in the valve diverter body to a driveline retarder outlet opening in the valve diverter body in isolation from the bypass outlet opening in response to the operation data, the valve moving to the first valve orientation from a second valve orientation, the second valve orientation fluidly coupling the coolant inlet opening to the driveline retarder outlet opening and a bypass outlet opening in the valve diverter body.

The inventors have appreciated that coolant flow through driveline retarders may be dynamically controlled as a function of vehicle operating conditions to maintain the operating efficiency of the cooling system and the vehicle. It should be appreciated that all combinations of the foregoing concepts and additional concepts discussed in greater detail below (provided such concepts are not mutually inconsistent) are contemplated as being part of the inventive subject matter disclosed herein. In particular, all combinations of claimed subject matter appearing at the end of this disclosure are contemplated as being part of the inventive subject matter disclosed herein. It should also be appreciated that terminology explicitly employed herein that also may appear in any disclosure incorporated by reference should be accorded a meaning most consistent with the particular concepts disclosed herein.

