摘要:
The disclosure describes an engine system having liquid and gaseous fuel systems, each of which injects fuel directly into an engine cylinder. A controller monitors and controls engine operation in a normal mode, during which the engine produces rated power, and in a limp-home mode, which is used when an abnormal operating condition of the gaseous fuel system is present. During limp-home mode operation, the engine uses more liquid fuel and less or no gaseous fuel relative to the normal mode, and produces power that is less than rated power.
摘要:
A fuel injector configured to inject a predetermined volume of fuel, such as heavy fuel oil, is disclosed. The disclosed injector includes an injector body that defines a fuel inlet, a fuel passageway, and an orifice. The injector also includes a needle disclosed at least partially within the injector body. The needle is movable between a closed position where the needle blocks the orifice and an open position where the needle at least partially unblocks the orifice. At least the injector body and the needle define a nozzle chamber. The nozzle chamber is in communication with a high pressure fuel passageway and the orifice. The fuel passageway and nozzle chamber have a combined volume greater than the predetermined injection volume. The combined volume of the nozzle chamber and fuel passageway act as a damper to alleviate the effects of pressure overshoot, pressure oscillations and water hammer
摘要:
A fuel system includes a plurality of fuel injectors each defining a nozzle supply passage, a nozzle outlet and a low pressure space. The fuel system includes a plurality of mechanically actuated pressure intensifiers each including a tappet and being positioned partially within one of the fuel injectors, and a common rail fluidly connecting with each of the fuel injectors. Each of the fuel injectors further includes an injection pressure control mechanism having an injection pressure control valve. Each injection pressure control valve blocks the corresponding pressure intensifier from the common rail and fluidly connects the pressure intensifier with the low pressure space at a first position, and fluidly connects the pressure intensifier with the common rail and blocks the pressure intensifier from the low pressure space at a second position. Injecting fuel via operating the fuel system may include operating the fuel system in a low leakage mode where the pressure intensifier displaces fuel at a low pressure, between high pressure injections.
摘要:
Mixing of lubrication fluid and pumped fluid within a pump can undermine lubricity of the lubrication fluid and/or contaminate the pumped fluid (e.g. fuel) with lubrication fluid. In order to reduce mixing of fluids within a high pressure pump of the present disclosure, a lubrication fluid is supplied to the high pressure pump. A low pressure pump supplies a second fluid to the high pressure pump. The pressure of the second fluid is increased within at least one piston bore of the high pressure pump. Mixing of the lubrication fluid and the second fluid is reduced by fluidly connecting a weep annulus which is opened to the at least one piston bore to a low pressure pump inlet of the low pressure pump.
摘要:
A valve has a housing defining an interior of the valve. The valve has a first passage in the housing and a second passage in the housing. The valve has a flow limiter movable between a first position at which the first passage is in fluid communication with the second passage and a second position at which the first passage is not in fluid communication with the second passage. The valve has a flow restriction device movable between a first position at which a first flow rate is permitted into the interior of the valve and a second position at which a second flow rate is permitted out of the interior of the valve. The first flow rate is greater than the second flow rate.
摘要:
A method is provided for predicting a quality characteristic of a product to be manufactured. The method may integrate one or more of feature and tolerance information associated with the product, manufacturing characteristic information associated with the manufacture of the product, measurement capability characteristic information associated with the manufacture of the product, assembly characteristic information associated with an assembly of the product, and desired quality characteristic information associated with the product. Based on the integrated information, the quality characteristic of the product may be predicted.
摘要:
A pressure relief valve includes a valve body defining an inlet configured to receive fluid from a fluid system, a pressure control orifice ending in a valve seat, and a guideway extending from the valve seat. The pressure relief valve further includes a valve closing member configured to abut the valve seat in a closed position and to be displaced from the valve seat in an open position, thereby releasing pressure from the fluid system. The pressure relief valve also includes a flow member including a stem and a flow plate. The stem is operably associated with the valve closing member and is configured to reciprocate within the guideway. The pressure relief valve further includes a valve spring operably associated with the valve body.
摘要:
The present invention relates to high speed control valves which are especially applicable for use in fuel injection systems. Producing a valve with a quick response time within acceptable packaging constraints and with a structure that allows the valve to be mass produced with consistent performance between valves is extremely problematic. By moving flow restrictions within the valve away from the valve seats, flow forces on the valve member can be reduced, while possibly also permitting a reduction in the necessary travel distance of the valve member to improve response time and other performance characteristics. The valve is particularly applicable in controlling hydraulic pressure applied to the closing hydraulic surface of a direct control needle valve in a fuel injector.
摘要:
In one class of fuel injection systems, the individual fuel injectors cycle between high and low pressure during and between injection sequences in a given engine cycle. The fuel injectors may be hydraulically actuated, mechanically actuated, and possibly include common rail injectors equipped with an admission valve that enable the fuel injectors to cycle between high and low pressures. Many of these fuel injection systems also include a directly controlled nozzle valve that can apply or relieve pressure on a closing hydraulic surface associated with the nozzle valve. The nozzle valve is typically spring-biased and therefore has a pre-defined valve opening pressure that defines at what fuel pressure the nozzle valve will open when pressure is relieved on its closing hydraulic surface. While these fuel injection systems can produce a wide variety of rate shapes and injection sequences, generally, an injection sequence of particular interest is one that includes a relatively small volume pilot injection followed quickly in time by a relatively large volume main injection. In order to make the accuracy of the pilot injection more consistent, the nozzle valve is held closed while fuel pressure in the fuel injector builds and surpasses the valve opening pressure of the nozzle valve. This strategy helps to alleviate sensitivity of the pilot injection volume to inherent variability factors, such as geometrical tolerances, within and between fuel injectors.
摘要:
A method is provided for predicting a quality characteristic of a product to be manufactured. The method may integrate one or more of feature and tolerance information associated with the product, manufacturing characteristic information associated with the manufacture of the product, measurement capability characteristic information associated with the manufacture of the product, assembly characteristic information associated with an assembly of the product, and desired quality characteristic information associated with the product. Based on the integrated information, the quality characteristic of the product may be predicted.