Bosch, Abex And Jet Pipe Servo Valves: The Lowdown
The jet pipe servo valve is, for modern air travel, a component crucial for many applications. For one, it allows for the speedy and smooth adjustment of flight trajectories. Typically, the operation of a jet pipe servo valve involves the direction of high pressure gas into a movable nozzle. Usually, such a nozzle will be mounted in a housing equipped with two ports, each on different sides of a flapper.
A fluid amplifier is typically also provided, and should be equipped with a pair of outputs placed facing the control ports of the servo valve. The essential concept of a fluid amplifier is to pass a fluid through two chambers, the first of which has entry points for two alternate fluid supplies, weaker than the primary source, directed perpendicularly against the primary stream. This results in higher levels of turbulence in the second, larger chamber, so that the stream exits at either one or the other of the exit ports at greater pressure or velocity than that at which it entered the device.
The design of the fluid amplifier allows one to selectively direct gas or fluid at either one or the other of the jet pipe servo valve’s inputs. Passing through these inputs, the fluid in turn places different pressures on the flapper, thus pivoting the attached nozzle, directing the high pressure gases it controls out of the servo valve’s exist ports. This gas is in turn directed so as to set off an actuator of the piston-type in order to control the motion of jet vanes or similar navigational elements.
Some of the most highly regarded jet pipe servo valves of the eighties were manufactured by Abex. With its famous 1982 Boeing 767 Jet Pipe Servo Valve, the company has forever made its name as a producer of reliable, long lived valves. Of course, Abex, has limited independence now, operating primarily with other companies – for instance, most of the company’s hydraulic pumps, valves and motors are marketed under the Abex-Denison brand. Still, relations with a company like Denison, the makers of the first hydraulic machine and a subsidiary of Parker Hannefin, can itself be taken as a great mark of respectability.
Of course, Abex and Denison alike are small potatoes in the face of superbrands like Bosch, the best-known brand name of Robert Bosch GmbH, which, at present, stands out as the planet’s single biggest supplier of automobile components. With relationships with pretty much every car company in existence, the Bosch Group is known to include over 250 companies, and reported sales of 46.3 billion Euro for the fiscal year of 2007.
Bosch’s various companies manufacture products that find applications in just about every industry – thus its lines naturally include jet pipe servo valves, among a million other components. Notable for the purposes of the above discussion is the Bosch subsidiary Bosch Rexroth, which produces technologies that serve its parent companies two central markets, namely mobile hydraulics and factory automation. Included in its lines are technologies for moving, driving and controlling machines.
Bosch’s history of invention and innovation is a long one, and many a patent application has passed out its doors only to find its way into the history books. Indeed, founder Robert Bosch, along with Frederick Richard Simms, were pioneers in terms of developing practically usable, high tension magnetos. Magnetos are electrical generators that make use of magnets to create pulses of alternating current at high voltages. At one point, Bosch’s magnetos served as the primary component in the ignition system of most internal combustion engines, providing the power the spark plugs need to initiate the combustion reaction. The role of the magneto in Bosch’s history is clearly announced through the company’s choice of logo – a 2-Dimensional image of one.
