摘要:
The injection pump has a pump piston driven with a constant stroke which pumps fuel at injection pressure to an injection nozzle so long as an electrically actuated overflow valve blocks the flow of the fuel overflowing via an overflow conduit to a low-pressure chamber. The overflow valve is a needle valve, the valve needle of which, opening inward toward a pressure chamber that can be placed under injection pressure, by means of a conical closing surface radially defining a needle tip controls a valve seat that widens conically toward the pressure chamber. The cone angle of the closing surface is larger than the cone angle of the associated valve seat and the closing surface forms a sealing edge, the diameter of which is equal to or only slightly smaller than the guide diameter of the guide shank on the valve member. In a preferred embodiment, the needle tip of the valve member has an external contour on its end, adjacent to the closing surface, which directs the fuel flow and reinforces the opening movement. The injection pump is particularly suitable for high-pressure injection in Diesel engines, in order to attain an exact electrical control of the supply onset and supply quantity, if a reservoir chamber defined by a deflecting piston is connected to a high-pressure chamber that includes the pump work chamber.
摘要:
A fuel injection arrangement for internal combustion engines, particularly for diesel engines, is indicated, in which the fuel injection is divided into an advance injection and a main injection for the purpose of noise reduction. An advance injection unit (27) is provided for the purpose of proportioning the advance injection quantity and a fuel injection pump of a conventional construction is provided for proportioning the main injection quantity. For an optimal design of the advance injection quantity with respect to noise reduction without influencing the main injection quantity, the advance injection unit (27) comprises a high-pressure storage (28), which is compressed to injection pressure, and at least one solenoid valve (30), which is controlled with respect to time. The advance and main injections are preferably effected via separate nozzle cross sections (21, 22).
摘要:
Fuel injection nozzle for internal combustion engines includes a nozzle element having a front cusp formed with a conical valve seat face. At least one injection hole is provided in the front cusp. The outer wall area of the front cusp which is disposed opposite to the valve seat face has a lower hardness than that of the inner wall area forming the valve seat face. When the injection hole extends from a pocket hole, preferably the outer wall area of the front cusp encompassing the picket hole has a lower hardness than that of the opposite disposed inner wall area. The intermediary center wall area preferably has a still lower hardness than the outer wall area. Thus, it is achieved that the front cusp of the nozzle element has a higher rigidity than in a known embodiment, without the valve seat face losing any hardness or that the protection of the outer wall area of the front cusp being unduly severly reduced against abrasive wear.
摘要:
The invention relates to a fuel injection nozzle in which a control piston acts on the valve needle, which control piston can also be acted upon by another fluid with an arbitrarily changeable pressure. In this manner it is relatively simple to meet the ever increasing requirements to apply an influence of engine characteristic values to the fuel injection process.
摘要:
The invention relates to a fuel injection nozzle in which a control piston acts on the valve needle, which control piston can also be acted upon by another fluid with an arbitrarily changeable pressure. In this manner it is relatively simple to meet the ever increasing requirements to apply an influence of engine characteristic values to the fuel injection process.
摘要:
A fuel injection nozzle is proposed, intended in particular for Diesel engines, in which an induction coil is installed in an intermediate disc. The coil core is embodied by a pressure element and a valve needle in force-locking contact therewith. An annular permanent magnet is secured either on the pressure bolt or on the intermediate plate. This embodiment of an injection nozzle, as a so-called needle stroke transducer, is used when it is desired to ascertain the duration of injection and especially the onset of injection.
摘要:
A fuel injection nozzle in which the needle valve has been improved so that all similarly constructed nozzles will exhibit exactly the same flow cross section with a fully opened valve, and so that, with a constant injection pressure, the fuel quantity injected will not vary between the various nozzles serving the engine. The needle valve is provided with a cyclindrical section, which together with an edge region of the nozzle body defines the narrowest flow cross section obtainable with a spray-forming portion of the needle valve at a fully opened position of the needle valve.
摘要:
Fuel injection nozzle for internal combustion engines comprising an inwardly opening valve needle (14) and a nozzle bore hole (20) into which a throttle pivot (18) of the valve needle (14) dips during an initial lift. The throttle pivot (18) is provided with at least two flattened portions (30, 32 and 30, 32, 40, respectively) for forming preferred pass-through cross sections in the nozzle bore hole (20), wherein at least two flattened portions (30, 32 and 32, 40, respectively) end in different cross-sectional planes of the throttle pivot (18). Accordingly, a stepwise enlargement of the total cross section in the nozzle bore hole (20) can be achieved during the initial lift of the valve needle (14) with manufacturing methods which can be controlled in a favorable manner.
摘要:
Fuel injection nozzle for internal combustion engines includes a first closing spring which acts continuously on the valve needle by means of a central pressure pin and, in addition, a second closing spring which acts continuously on the valve needle by means of a pressure piece after covering the distance of an initial stroke. The pressure piece is supported at the nozzle body by means of an intermediate bush during the initial stroke. The initial stroke is limited by means of the shoulders at the valve needle and the intermediate bush, whereas the total stroke is limited by means of the shoulders at the intermediate bush and the intermediate disk. Accordingly, the initial stroke can be adjusted very accurately to a desired magnitude merely by means of grinding the valve needle and does not change during the assembly of the injection nozzle.
摘要:
The invention proposes a fuel injection nozzle wherein the mounting, for example in the form of a cap nut or sleeve nut, used for clamping the fuel pressure line to the nozzle holder, is replaced by a cap screw, the outer thread of which engages a corresponding threaded area in the engine bore which is arranged to receive the nozzle. This has the result that, together with the mounting of the fuel line, the injection nozzle is simultaneously firmly clamped to the engine.