A novel combustion chamber valve and fuel system for driven fastener hand tool is disclosed having a fuel pump disposed parallel to the combustion and piston chambers. Pressure applied a safety at the nose of the tool is activates the fuel pump in a common direction. Pressure applied on a trigger activates the valve system prior to firing in a common direction. The valve system employs a central shaft coupling three valves, an inlet valve using a novel wedged circumferential edge seal, a control valve using a novel edge circumferential seal with a ventilated support, and a charging exaust valve using a face seal.

A fastener driver includes a drive blade movable from a retracted position to a driven position for driving a fastener into a workpiece and a gas spring mechanism for driving the drive blade from the retracted position to the driven position. The gas spring mechanism includes a piston movable between a retracted position and a driven position. The fastener driver further includes a first return mechanism for moving the drive blade from the driven position toward the retracted position, and a second return mechanism for moving the piston from the driven position toward the retracted position.

A driving tool including a first mode wherein a mechanical starting control is performed, and a second mode wherein an electrical starting control is performed, where these modes are configured to be switchable. Only in the second mode, if the elapsed time between the on-operation of a trigger and an on-operation of a contact arm does not exceed a reference time T.sub.0, then a second actuation portion can be turned to an on-position to perform a driving operation. In the first mode, in contrast to the electric control, without consuming battery power, the driving operation can be performed by the mechanical control that is made by an operational order of the trigger and subsequently the contact arm. Because of this configuration, even if power supply is shut off, the driving operation by the first mode can be continued.

A driving tool drives a fastener by a striking mechanism which is operated by a fluid. The driving tool includes a trigger, a contact arm, a contact lever and a regulator. The trigger and the contact arm receive manipulations and the contact lever switches operating states of the striking mechanism according to operations of the trigger and the contact arm. The regulator switches operating states of the contact lever according to the contact arm. The regulator includes a regulation member and a controller. The regulation member regulates the contact lever at an operation standby position where the contact lever is operated by the contact arm. The controller operates the regulation member and includes first and second cylinders. The first cylinder operates the regulation member. The second cylinder to which a fluid operating the striking mechanism is partially supplied and generates a driving force for driving the first cylinder.

A driving tool drives a fastener by a striking mechanism. The driving tool includes a trigger, a contact arm, a contact lever and a regulator. The trigger and the contact arm receive manipulations which operate the striking mechanism. The contact lever is movable according to operations of the trigger and the contact arm and switches operating states of the striking mechanism. The regulator regulates a movement of the contact lever according to a movement of the contact arm in which another manipulation is released. The regulator operates with a fluid for operating the striking mechanism, and keeps the contact lever at an operation standby position where the contact lever is operated by manipulation of the contact arm for a predetermined time period by controlling a flow rate of the fluid.

A driving tool drives a fastener supplied to a nose using a striking mechanism. The driving tool includes a trigger, a contact arm, a contact lever and a regulator. The trigger receives a manipulation which operates the striking mechanism. The contact arm reciprocates and receives another manipulation which operates the striking mechanism. The contact lever operates according to operations of the trigger and the contact arm and switches operating states of the striking mechanism. The regulator regulates a movement of the contact lever in a range from an operable position where the striking mechanism is operable by the contact lever to an operation standby position where the contact lever is operable by the contact arm, according to a reciprocating movement of the contact arm, and switches operating states of the contact lever according to the contact arm.

A driving tool capable of avoiding blank shot after a predetermined time has elapsed when performing a bump firing and capable of smoothly performing the bump firing is provided. The driving tool includes: an accumulator chamber which accumulates compressed air, a nose section provided on a housing; a cylinder; a trigger, and a push lever provided in the nose section, and when the trigger and the push lever are operated, the compressed air is supplied into the cylinder. The driving tool further includes: a delay valve which prevents the compressed air from being supplied into the cylinder when the push lever is not operated within a predetermined time after the trigger is operated: and a switching valve which supplies the compressed air of the accumulator chamber to the delay valve when the trigger is operated, and discharges the compressed air supplied to the delay valve to an outside of the housing when the push lever is operated within the predetermined time.

The invention relates to a driving-in tool, comprising a driving-in piston, guided in a cylinder, for driving a nail element into a workpiece, and a combustion chamber which is arranged at the driving-in piston and can be filled with an ignitable fuel-gas mixture. A positive pressure of the fuel-gas mixture in the combustion chamber can be produced by a movement of the driving-in piston. At least one of the two, the combustion chamber or the cylinder, is connected to an external space via a valve member, the positive pressure of the fuel-gas mixture produced by the driving-in piston being selectively adjustable by means of the valve member.

A driving tool including a first mode wherein a mechanical starting control is performed, and a second mode wherein an electrical starting control is performed, where these modes are configured to be switchable. Only in the second mode, if the elapsed time between the on-operation of a trigger and an on-operation of a contact arm does not exceed a reference time T.sub.0, then a second actuation portion can be turned to an on-position to perform a driving operation. In the first mode, in contrast to the electric control, without consuming battery power, the driving operation can be performed by the mechanical control that is made by an operational order of the trigger and subsequently the contact arm. Because of this configuration, even if power supply is shut off, the driving operation by the first mode can be continued.

A driving device includes an operable striking unit, a piston upper chamber configured to operate the striking unit by gas pressure, a housing, a head cap provided in the housing, a passage provided in the head cap, and an exhaust valve operably provided in the housing and configured to open and close the passage. The exhaust valve includes a contact portion and a non-contact portion, the contact portion comes into and out of contact with the head cap on an outer side of the passage in a radial direction of the passage, the non-contact portion is provided on an inner side of the contact portion in the radial direction of the passage, and the non-contact portion is provided at a position separated from the head cap in a state where die contact portion is in contact with the head cap.