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Power Steering There are a couple of key components in power steering in addition to the rack-and-pinion or recirculating-ball mechanism.
Pump
The hydraulic power for the steering is provided by a rotary-vane pump (see diagram below). This pump is driven by the car's engine via a belt and pulley. It contains a set of retractable vanes that spin inside an oval chamber.
As the vanes spin, they pull hydraulic fluid from the return line at low pressure and force it into the outlet at high pressure. The amount of flow provided by the pump depends on the car's engine speed. The pump must be designed to provide adequate flow when the engine is idling. As a result, the pump moves much more fluid than necessary when the engine is running at faster speeds.
The pump contains a pressure-relief valve to make sure that the pressure does not get too high, especially at high engine speeds when so much fluid is being pumped.
Rotary Valve
A power-steering system should assist the driver only when he is exerting force on the steering wheel (such as when starting a turn). When the driver is not exerting force (such as when driving in a straight line), the system shouldn't provide any assist. The device that senses the force on the steering wheel is called the rotary valve.
The key to the rotary valve is a torsion bar. The torsion bar is a thin rod of metal that twists when torque is applied to it. The top of the bar is connected to the steering wheel, and the bottom of the bar is connected to the pinion or worm gear (which turns the wheels), so the amount of torque in the torsion bar is equal to the amount of torque the driver is using to turn the wheels. The more torque the driver uses to turn the wheels, the more the bar twists.
The input from the steering shaft forms the inner part of a spool-valve assembly. It also connects to the top end of the torsion bar. The bottom of the torsion bar connects to the outer part of the spool valve. The torsion bar also turns the output of the steering gear, connecting to either the pinion gear or the worm gear depending on which type of steering the car has.
As the bar twists, it rotates the inside of the spool valve relative to the outside. Since the inner part of the spool valve is also connected to the steering shaft (and therefore to the steering wheel), the amount of rotation between the inner and outer parts of the spool valve depends on how much torque the driver applies to the steering wheel.
Animation showing what happens inside the rotary valve when you first start to turn the steering wheel
When the steering wheel is not being turned, both hydraulic lines provide the same amount of pressure to the steering gear. But if the spool valve is turned one way or the other, ports open up to provide high-pressure fluid to the appropriate line.
It turns out that this type of power-steering system is pretty inefficient. Let's take a look at some advances we'll see in coming years that will help improve efficiency.
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What is the use for a power steering pump?
A power steering pump is an essential part of the steering mechanism of your car. This is run directly from the engine (via a pulley system) and provides the hydraulic power for the steering system.
Is the Nissan march 2005 model power steering works with oil or isit eletrical?
Is the nissam march 2005 model power steering works with oil or is it eletrical?
How do you build a steering mechanism for a go kart?
buy a fusion scooter, and take off the steering mod and make a wooden angled mod then put the fusion steering mod in it. it is a crappy steering mod, but it works
When you have your power steering repaired do you have to have anything else repaired?
A lot of the time if your pump goes, then your steering box is also gone. If it works then it works..
Your dealership broke the steering column locking mechanism on your 2001 Jeep Cherokee They insist there is no steering column locking mechanism?
Answer: The dealership is correct. The 2001 XJ does not have a steering column locking mechanism.
Where is a rack and pinion mechanism used?
A steering mechanism of a car
What would cause the power steering to catch and not steer smoothly on my 1997 Toyota Camry?
If you are lucky tie rod (inner or outer) has to be replaced. If you are not lucky you will have to replace all steering mechanism (steering rack).
How electric power steering system in a car works?
alto ricng full
How the electric steering work and what is the advantage of electric steering system than the conventional steering?
Electric (Power) Steering works from a hydraulic pumping system, advantages are lighter steering for easier control.
Power steering works to the left not to the right?
It's a problem with either the rack and pinion, or the steering gear, depending on which your vehicle utilizes.
Is it necessary to replace complete rack-pinion or can you just install new seals when the steering is leaking Assuming power steering fluid seal would not work?
Yes, you can replace just the "boots" on the end of a rack-and-pinion steering provided that the mechanism is not damaged. Unfortunately, the boot is just a dust cover and if the inner mechanism has started leaking there really isn't much that can be done without completely disassembling the mechanism. The fluid in a rack assembly is under pressure from the Power Steering pump and once it starts leaking the rack is pretty much "done".
How do you diagnose a power steering problem in a 2007 Chevy Cobalt?
There isn't much to diagnose. Either the electronic steering works or does not. You can check that the wiring harness or wires are not damaged, but when a power steering failure occurs with the electronic steering on the cobalt the electronic steering component must be replaced.
