Patent Application
20080314572
This invention relates to a lubrication system for a lubricated mechanism, such as an engine, transmission or other mechanism including an oil cooler and a bypass for the oil cooler.
It is known in the art, relating to engines, transmissions and other mechanisms, to provide an oil cooler for maintaining the oil temperature below a desired maximum operating limit. The cooler may have a core with a plurality of oil passages in heat exchange relation with coolant passages adapted to carry cooling fluids such as water or air.
In operation, oil degradation or deposits, as well as high oil viscosity when the oil is cold, may impede oil flow through the cooler oil passages. To avoid inadequate lubrication of the mechanism, a cooler bypass may be provided to maintain oil flow to the mechanism components until the oil warms to normal operating temperature, or the cooler oil flow is restored by changing the oil or servicing or replacing the oil cooler. Devices such as a pressure actuated bypass valve or a simple orifice may be provided for this purpose. However, such arrangements may add cost or complexity to a lubrication system.
The present invention provides a lubrication system with an oil cooler for an engine or other lubricated mechanism. The oil cooler includes a connector through which the oil cooler is connected to an oil supply passage and a return oil passage in an engine crankcase or other supply source. The connector includes a seal face to which inlet and outlet passages to and from a cooler core are connected with oil supply and return passages in an engine or other connected mechanism. A continually open oil bypass is provided by forming a groove or slot in the seal face of the oil cooler connector, the slot extending between the inlet and outlet passages of the oil cooler and forming the cooler oil bypass. Alternatively, a bypass may be formed by a slot in a mating engine or mechanism connector, connecting with the engine oil supply and return oil passages.
These and other features and advantages of the invention will be more fully understood from the following description of certain specific embodiments of the invention taken together with the accompanying drawings.
Referring now to the drawings in detail, numeral 10 generally indicates part of a lubrication system for a lubricated mechanism, such as an engine 12, a transmission or other mechanism, not shown. Engine 12 includes a suitable housing such as a cylinder block or crankcase 14 with an oil sump or oil pan 16 for containing a supply of lubricating oil. Within the crankcase or oil pan, an engine driven oil pump, not shown, is provided for supplying pressurized oil from the oil pan 16 to the various internal moving components of the engine 12.
The lubrication system includes an oil cooler 18 having a housing 20 which may be mounted at any convenient location, such as on a side 22 of the cylinder block or crankcase 14. An exemplary form of oil cooler 18 with housing 20 is illustrated in
The oil cooler connector is fastened, as by bolts 44, in opposed face relation with a similar seal face 46,
In order to provide a cooling fluid for the oil cooler 18, the oil cooler core 24 includes coolant passages 58, or an equivalent volume, with which the oil passages are in heat exchange relation within the oil cooler core 24. The passages 58 or volume may have any suitable flow path through the core, such as a return flow path from a coolant inlet header 60 to a return flow header 62 and back to a coolant outlet header 64. Inlet and outlet connections 66, 68 connect the headers 60, 64 with the engine cooling system, not shown, to provide engine coolant to the cooler core passages (volume) 58.
If the oil cooler is connected to a transmission or other lubricated mechanism, coolant may be supplied by an associated engine cooling system, or another source of coolant or cooling fluid may be provided. Any suitable coolant may be used including antifreeze containing liquid coolants, as well as air or other suitable gaseous fluids if desired.
In accordance with the invention, a simplified oil bypass passage is provided between the engine 12 and the oil cooler core 24. The passage replaces a higher cost pressure actuated bypass valve of a prior system and avoids the addition of an orifice, which would involve additional costs. Preferably, as shown in
It should be understood that other forms of open sided grooves or slots (such as V-shaped, or U-shaped or forming a curved passage in the seal face, could be substituted for the preferred, straight slot with rectangular cross section configuration.
Assembly of the oil cooler onto the engine requires only the addition of a “perimeter seal” gasket 74, shown in
The gasket 74,
It is apparent that the present invention provides a simple but effective oil bypass for an oil cooler, which provides continuous oil bypass flow to protect the lubricated components of an engine or mechanism from damage due to oil starvation in spite of high oil viscosity or plugging of the oil passages of an associated oil cooler. The bypass arrangement is easily formed in a junction of inlet and outlet oil passages in a connector in which a bypass groove or slot may be machined or formed between the passages.
While the invention has been described by reference to certain preferred embodiments, it should be understood that numerous changes could be made within the spirit and scope of the inventive concepts described. Accordingly, it is intended that the invention not be limited to the disclosed embodiments, but that it have the full scope permitted by the language of the following claims.
