Patent ID: 6988564

Claim:
A diesel hammer system for driving a pile, comprising: a housing; an anvil member supported by the housing; a clamp assembly adapted to connect the anvil member to the pile; a ram member disposed within the housing; a fuel pump system for injecting fuel into a combustion chamber defined by the housing, anvil member, and the ram member; and a coupling system that detachably engages the ram member to raise the ram member from an impact position to an upper position, the coupling system comprising a trigger member that, when engaged, causes the coupling system to release the ram member; a trigger projection mounted on the housing to engage the trigger member to cause the coupling system to release the ram member at the upper position; and a pre-trigger system comprising: a pre-trigger member movable between an extended position and a retracted position; wherein when the pre-trigger member is in the extended position, the pre-trigger member engages the trigger member as the ram member moves from the impact position towards the upper position to cause the coupling system to release the ram member at a pre-trigger position; and when the pre-trigger member is in the retracted position, the pre-trigger member does not engage the trigger member as the ram member moves from the impact position to the upper position; whereby when the pre-trigger member is in the retracted position, the ram member moves from the impact position to the upper position and back to the impact position such that the ram member engages a fuel pump system to cause fuel to flow into the combustion chamber; when the pre-trigger member is in the extended position, movement of the ram member from the impact position to the pre-trigger position and back to the impact position does not cause fuel to be forced out of the fuel chamber and into the combustion chamber.