Where means are provided to prevent the fuel admission valve from being operated whilst the cylinder to which that valve connected is being used for starting or running the engine on compressed air or other fluid, or when the cylinder is cut out of action by the non-delivery of fuel, or of starting or running air, or other fluid, to it, it ordinarily occurs that the fuel oil delivered by the fuel-pump accumulates at the fuel admission valve which is prevented from opening. There is in these circumstances liability of an excessive charge of oil being delivered to the cylinder when the fuel admission valve is brought into action.
The object of this invention is to provide means for preventing such an accumulation of fuel.
The invention consists essentially of a by-pass valve placed in the delivery pipe from the fuel-pump to the fuel admission valve, which by-pass valve remains closed when the fuel admission valve with which it is in connection is in operation. This by-pass valve is provided with a lifting lever or its equivalent, operated by means of a rod connected to the mechanism provided for the cutting out of the fuel admission valve from operation. The action is such as will cause the by-pass valve to be opened when the fuel admission valve is out of operation.
The feature claimed as novel is a fuel by-pass valve positively connected to the mechanism which puts the fuel admission valve out of action at certain times and in such a manner as to prevent the possibility of accumulation of oil above the fuel admission valve of the cylinder whenever the latter valve is inoperative.