Inlet Metering Valve for Injection Pump Fuel Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fuel injection systems face inefficiencies and noise issues due to the need for frequent actuation of high-pressure outlet metering valves, which require significant electromagnetic energy and result in overheating and compromised packaging design.
Innovation Solution
An injection pump system with a control valve that inhibits fuel supply during the intake stroke when rail pressure is within a target range, allowing fuel to be delivered only when needed, thereby improving high-pressure design and actuator performance while reducing energy consumption and noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If an outlet metering valve is used in the high pressure fuel line to control fuel delivery, then the pump chamber can be filled on every stroke and supply to the fuel rail is controlled, but the valve is subjected to seating forces proportional to valve area and rail pressure requiring small valve diameter while hydraulic requirements demand sufficiently large valve lift and high spring loads, resulting in significant electromagnetic energy consumption and overheating
Solution Approach 1:
The patent introduces an inlet metering valve as an intermediary device positioned in the low-pressure fuel line upstream of the injection pump. This mediator controls the fill volume of the pump chamber by regulating fuel flow into the pump, thereby indirectly controlling the fuel delivery to the rail without requiring a high-pressure outlet valve to be frequently actuated. The inlet metering valve operates in a low-pressure environment, significantly reducing the electromagnetic energy consumption and heat generation associated with valve actuation.
2Productivity
If an outlet metering valve is positioned in the high pressure fuel line to control fuel supply, then pumping chamber filling is enabled on every stroke, but the compromise between high pressure design, actuator performance and packaging is forced
Solution Approach 1:
The patent inverts the conventional approach by placing the metering valve in the low-pressure inlet line rather than the high-pressure outlet line. The inlet metering valve controls the fill volume of the pump chamber by regulating fuel flow into the pump during the intake stroke. This inversion allows the valve to operate in a low-pressure environment, eliminating the need for high-pressure rated components and simplifying the overall packaging and design constraints.
3Stress or pressure
If traditional inlet metering valves are used to control rail pressure by strangling fuel flow into the injection pump, then flow rate control is achieved, but the response is slow and partial filling of the pumping chamber is required to match pressure and delivery demand
Solution Approach 1:
The inlet metering valve performs preliminary action by controlling the fill volume of the pump chamber before the pumping stroke begins. By regulating the amount of fuel introduced into the pump during the intake stroke, the valve pre-configures the pump chamber with the appropriate fuel quantity needed for the subsequent delivery stroke. This preliminary control enables faster response compared to traditional strangulation methods, as the valve sets the fuel volume in advance rather than continuously restricting flow during pressure matching.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution enhances efficiency and reduces noise by pumping fuel only when required, allowing for improved packaging flexibility and increased actuator frequency, while maintaining rail pressure within a target range.
Implementation Method 1
The control valve is controllable in an open and closed position. In the closed position, the control valve inhibits supply of fuel to the injection pump during an intake stroke of the injection pump when the rail pressure is within a target pressure range
Implementation Method 2
The plunger draws a fill volume of fuel into the injection pump when it retracts and then pressurises the fuel when it advances to complete a pump cycle
Implementation Method 3
The control valve comprises an electromagnetic actuator arranged to provide open-close functionality
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention relates to an injection pump system (1). An injection pump (3) is provided for supplying high pressure fuel. A low pressure fuel line (5) is provided in fluid communication with an inlet of the injection pump (3). A high pressure fuel line (7) is provided in fluid communication with an outlet of the injection pump (3) and a fuel rail. A control valve (27) is provided for controlling filling of the injection pump (3). The injection pump system is provided with a control unit for controlling operation of the control valve (27). The control unit is configured to close the control valve (27) to inhibit the supply of fuel to the injection pump when the rail pressure is within a target pressure range. The invention also relates to a method of operating an injection pump system. An aspect of the invention also relates to a fuel injection system.