A fuel injector includes an injector body and a valve stack within the injector body that includes a valve seat plate. The valve seat plate includes a pressure control passage for controlling fuel injection, and a valve seat positioned fluidly between the pressure control passage and a low-pressure drain. The valve seat plate includes a pressure-limiting annular groove that extends circumferentially around the valve seat and axially inward from a side of the valve seat plate where the valve seat is located. The groove enables deformation in response to pressure differences across the valve seat plate in a manner that limits stress concentrations.

A handheld combustion powered fastening tool may include a driving system that drives fasteners into workpieces in response to combustion of fuel by the driving system. A fuel delivery system may supply fuel to the driving system. The fuel delivery system may include a fuel canister storing liquid fuel, such as liquid hydrocarbons such as propane, and a fuel metering valve supplying a previously set amount, or volume, of fuel from the fuel canister to the driving system for combustion.

An injector, comprising, an injector body comprising, an inner wall that defines an injector cavity for fluid, at least one inlet channel into the injector cavity, and at least one outlet channel from the injector cavity, a plunger that defines at least one passageway between the injector cavity and the at least one outlet channel, the plunger being movable longitudinally in the injector cavity between at least: a first open arrangement in which the at least one passageway is positioned to direct fluid into the at least one outlet channel at a first position, and a second open arrangement in which the at least one passageway is positioned to direct fluid into the at least one outlet channel at a second position different from the first position.

A fuel injector, preferably a dual fuel injector, for an internal combustion engine is disclosed. The fuel injector comprises first and second valve needles (80, 100) arranged to control the injection of first and second fuels, first and second control chambers (88, 10) associated with the first and second valve needles (80, 100) respectively, a first control valve (26) comprising a first control valve member (48) and arranged to vary the pressure of a control fluid in the first control chamber (88) so as to cause opening and closing movement of the first valve needle (80), and a second control valve (28) comprising a second control valve member (60) and arranged to vary the control fluid 10 pressure in the second control chamber (110) so as to cause opening and closing movement of the second valve needle (100). The first and second control valve members (48, 60) are arranged for linear movement along a common control valve axis.

A handheld combustion powered fastening tool may include a driving system that drives fasteners into workpieces in response to combustion of fuel by the driving system. A fuel delivery system may supply fuel to the driving system. The fuel delivery system may include a fuel canister storing liquid fuel, such as liquid hydrocarbons such as propane, and a fuel metering valve supplying a previously set amount, or volume, of fuel from the fuel canister to the driving system for combustion.

A fuel injector includes an injector body and a valve stack within the injector body that includes a valve seat plate. The valve seat plate includes a pressure control passage for controlling fuel injection, and a valve seat positioned fluidly between the pressure control passage and a low-pressure drain. The valve seat plate includes a pressure-limiting annular groove that extends circumferentially around the valve seat and axially inward from a side of the valve seat plate where the valve seat is located. The groove enables deformation in response to pressure differences across the valve seat plate in a manner that limits stress concentrations.

An internal combustion engine includes a piston and a fuel injection valve. The fuel injection valve includes a first injection hole, a second injection hole, a first needle configured to open and close the first injection hole, and a second needle configured to open and close the second injection hole. The first injection hole and the second injection hole are configured such that a portion of a fuel spray injected from the first injection hole and a portion of a fuel spray injected from the second injection hole overlap each other at a position apart at a predetermined distance from a side wall of a cavity of the piston. The second needle is configured to start operation in order to open the second injection hole after a predetermined time has elapsed from a point of time when the first needle starts operation in order to open the first injection hole.

A fuel injection valve has first injection holes, second injection holes, a first needle that opens and closes the first injection holes, and a second needle. The fuel injection valve is arranged such that a part of fuel injected from the first injection hole and a part of fuel injected from the second injection hole are gathered together at a position spaced from the side wall of the cavity by a predetermined distance. The second needle starts operating to open the second injection holes, after a predetermined time elapses from a point in time at which the first needle starts operating to open the first injection holes.

A valve assembly for a fluid injector for an internal combustion engine includes a valve body with a valve recess, a central longitudinal axis, and a first axial end and a second axial end with respect to the central longitudinal axis. A valve needle is axially moveable within the valve recess with respect to the central longitudinal axis. In concurrence with a seal seat area the valve needle prevents a fluid flow through at least one flow hole in its closing position and otherwise enables it. Furthermore, the injector comprises a sac volume step adjacent to the seal seat area forming a part of an inner surface of a wall of the valve body and a sac volume being designed as one end of the valve recess and being limited by a further part of the inner surface of the wall of the valve body.

An injector, comprising, an injector body comprising, an inner wall that defines an injector cavity for fluid, at least one inlet channel into the injector cavity, and at least one outlet channel from the injector cavity, a plunger that defines at least one passageway between the injector cavity and the at least one outlet channel, the plunger being movable longitudinally in the injector cavity between at least: a first open arrangement in which the at least one passageway is positioned to direct fluid into the at least one outlet channel at a first position, and a second open arrangement in which the at least one passageway is positioned to direct fluid into the at least one outlet channel at a second position different from the first position.