Air springs control ride-height and load compensation on most heavy trucks today. An engine-driven air compressor maintains constant line pressure. As the distance between the axle and the frame decreases to less than a permissible minimum, a mechanical linkage actuates the air-leveling valve that admits air into the bladder. The same valve exhausts air when the distance between the frame and axle becomes excessive.
With no reservoirs to leak and no poppets to jam, the compact valve is unaffected by normal contamination. Of rotary design and containing only one moving part, the valve relies on lapped surfaces to affect a seal. Compressed air does not flow across sealing surfaces, but directly through the inside diameter of the seal. The relative movement of two circular, overlapping ports affects valve operation to ramp the flow rate and eliminate full-on/full-off behavior.
A 1.58 deadband prevents nuisance valve actuation during normal suspension travel. Exhaust and fill times are 11/2 to 21/2 times quicker than those of other systems. And an integral fast-flow dump port permits 10-sec system depressurization prior to driving away from parked trailers.
Mechanical link between truck’s axle and frame-mounted air-leveling valve helps maintain the pre-set ride-height pressure in the air
Air, together with any contaminants, flows into the leveling valve through the center of its pressure seal and does not flow across sealing surfaces.
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Paul O'Reilly Barksdale Inc. 3211 Fruitland Ave. Los Angeles, CA 90058 (800) 835-1060
Truchard will be presented the award at the 2014 Golden Mousetrap Awards ceremony during the co-located events Pacific Design & Manufacturing, MD&M West, WestPack, PLASTEC West, Electronics West, ATX West, and AeroCon.
Robots that walk have come a long way from simple barebones walking machines or pairs of legs without an upper body and head. Much of the research these days focuses on making more humanoid robots. But they are not all created equal.
The IEEE Computer Society has named the top 10 trends for 2014. You can expect the convergence of cloud computing and mobile devices, advances in health care data and devices, as well as privacy issues in social media to make the headlines. And 3D printing came out of nowhere to make a big splash.
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This discussion will examine what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.