Tunnel Type Sump With Oil Intake Valve Assembly

Abstract

An internal combustion engine is provided with oil intake pipes defining oil inlets on both sides of a tunnel type sump. Each oil intake pipe includes a valve which is operable to close the respective flowpath when the respective sump portion is tilted upwardly about the length axis of the engine. The inlets may be arranged to remain submerged in a minimum quantity of oil which is retained in each sump portion while the engine is tilted through its maximum angular range about both length and width axes.

1 . An internal combustion engine including:
 a plurality of combustion chambers spaced apart along a length axis of the engine,   at least one pump,   a sump for collecting oil,   a first flowpath having a first valve with a first valve element, and   a second flowpath having a second valve with a second valve element;   each flowpath having a respective inlet in the sump and extending from the respective inlet to the at least one pump;   the at least one pump being arranged to draw oil from the sump via each of the floe paths;   each valve element being biased to an open, rest position in a normal use position of the engine, and movable from the rest position to a closed position to block the respective flowpath by tilting of the engine about its length axis; wherein   the sump is divided into first and second sump portions arranged on opposite, first and second sides of a reference plane containing the length axis and bisecting the engine, the reference plane being vertical in the normal use position of the engine;   the inlets of the first and second flowpaths are arranged respectively in the first and second sump portions;   the first valve element is movable from the rest position to the closed position by movement of the first sump portion upwardly in rotation about the length axis relative to the second sump portion; and   the second valve element is movable from the rest position to the closed position by movement of the second sump portion upwardly in rotation about the length axis relative to the first sump portion.   
     
     
         2 . An internal combustion engine according to  claim 1 , wherein the first valve is arranged on the first side of the reference plane, and the second valve is arranged on the second side of the reference plane. 
     
     
         3 . An internal combustion engine according to  claim 1 , wherein each flowpath is defined by a respective pipe having a riser portion which extends downwardly into the respective sump portion towards the respective inlet. 
     
     
         4 . An internal combustion engine according to  claim 3 , wherein each valve is arranged in the flowpath between the at least one pump and the riser portion of the respective pipe. 
     
     
         5 . An internal combustion engine according to  claim 4 , wherein each valve element is movably retained within a valve body, the valve body extending downwardly away from the at least one pump towards the riser portion. 
     
     
         6 . An internal combustion engine according to  claim 5 , wherein each valve element is a ball. 
     
     
         7 . An internal combustion engine according to  claim 4 , wherein the engine is configured to retain a recommended quantity of oil, and each inlet is configured, when the recommended quantity of oil is retained in the engine, to remain submerged in the oil at all times during normal use of the engine while the engine is tilted through a maximum angular range, simultaneously about the length axis and about a width axis intersecting the length axis and normal to the reference plane. 
     
     
         8 . An internal combustion engine according to  claim 4 , wherein:
 the engine is configured to retain a recommended quantity of oil; and   each of the first and second sump portions is configured, when the recommended quantity of oil is retained in the engine, to retain at least a minimum quantity of said oil in the respective sump portion at all times during normal use of the engine while the engine is tilted:
 about the length axis to an intermediate angular position beyond which any increase in tilt about the length axis would cause the first or second valve element to move to the closed position, and simultaneously 
 through a maximum angular range about a width axis intersecting the length axis and normal to the reference plane; and 
   each inlet is configured, when at least said minimum quantity of oil is retained in each sump portion, to remain submerged in the oil at all times during normal use of the engine while the engine is tilted through a maximum angular range, simultaneously about the width axis and beyond said intermediate angular position about the length axis.