Solenoid Powered Gate Valve
Newly patented technology offers greater fluid control and reliability in off-highway and automotive applications.
TLX Technologies has patented technology for a solenoid-powered gate valve that greatly improves performance in a variety of applications. The technology provides a continuous membrane gate valve with high contamination resistance and greater reliability in real-world applications with less than perfect alignment. Availability of multiple control methods allows this new technology to replace poppet, diaphragm and spool valves and provide superior reliability and flow control.
DEF Coolant System
Selective Catalytic Reduction (SCR) systems utilizing Diesel Exhaust Fluid (DEF) is an established system for control of NOx emissions in diesel engines. DEF systems have a freezing point of -11°C (12°F). To thaw the fluid, engine coolant is circulated to the reservoir. Most systems have utilized unreliable poppet, diaphragm or spool valves to regulate flow to the DEF heating element. These valves are susceptible to contamination and do not perform well when a low pressure drop is required.
A superior method of diesel engine fluid coolant system is using a solenoid-powered gate valve. The automated or “commanded” valve responds to a signal from electronic controls. The coolant valve has a sprung gate assembled with elastic materials to reduce friction forces as the gate moves from open to close. The sprung gate contains a continuous elastic band assembled with two gate members. There is an interference fit within the gate providing a complete seal. The elastic quality of the gate allows system pressure to provide the sealing force needed in a closed position.
Alignment of the armature of the solenoid to the valve body is made through a mechanical rail system. This mechanical coupling to the armature lessens the chance of binding when the alignment of the armature, coil and stem is not perfectly concentric. The mechanical coupling can be accomplished in a variety of orientations making it easy to make the valve either normally open or normally closed.
Beyond DEF Applications
The technology of this solenoid-powered gate valve has applications beyond SCR diesel systems. The solenoid valve can be driven by direct voltage, PWM and peak and hold electric systems. The peak and hold signal will supply high force with smaller package sizes and lower heat generation. The smaller package size can be critical in engine applications, opening up possibility for flow control where previous solutions would not fit.
The gate valve can be operated on a proportional control basis, rather than normally open or normally closed, with a PWM signal. With proportional control, the gate valve can replace diaphragm valves in most applications. The gate valve will never need a pilot valve or line for operation. This simplifies the design of valves traditionally used in water and oil pump applications. Removing pilot lines reduces complexity of valve bodies, making them less expensive to manufacture and more reliable. The elastic gate reduces friction helping to reduce the force needed to operate the valve. Using a solenoid to actuate the gate provides quicker response time in a smaller package than any motorized gate valve.
Selecting the correct elastic material for the gate valve allows it to be used in most off-highway and automotive fluid systems. With proper material selection, life expectancy of the gate valve will meet or exceed off-highway and automotive requirements in water, oil or air systems. Off-highway applications will particularly benefit from the resistance to contamination. Overall the benefits of this new technology will provide better flow control in a variety of off-highway applications.
TLX Technologies is a leader in quick response, high-force custom solenoids. Our patented features and unique expertise in solenoid design allow TLX to provide effective solutions for our customers’ difficult off-highway and automotive applications.
***First published in IVT International magazine, June 2016***