How a variable steering ratio is achieved in a rack & pinion gear?
The ratio is made variable by changing the shape of the teeth on the rack. The space between the teeth is smaller at the centre of the rack and becomes larger as the pinion moves down the rack. Effort needed to turn the wheels stays approximately the same throughout the whole range of movement.
How does a variable pitch rack and pinion system work?
Some cars use variable ratio steering. This rack and pinion steering system uses a different number of teeth per cm (tooth pitch) in the centre than at the ends. The result is the steering is more sensitive when it is turned towards lock than when it is close to its central position, making the car more maneuverable.
How does variable ratio steering work?
When variable ratio is needed, the ECU disengages the electromagnetic lock and turns on the electric motor. The motor spins the planetary gear carrier. As a result, drive will go through the planetary gears and superimpose to the output shaft.
What is steering ratio in rack and pinion?
Rack and Pinion Steering Ratio Moog Parts defines “steering ratio” as the ratio of how far the steering wheel turns to how much the wheels turn. For example, if a 360-degree turn of the steering wheel causes a car’s wheels to turn 20 degrees, then that car’s steering ratio is 18:1 (360 divided by 20).
What are the advantages of variable ratio steering?
The advantage of an electronically controlled variable gear ratio Steering Assembly is that it adjusts to the ideal steering condition for whatever the car’s speed happens to be.
What is variable steering?
Variable-assist, variable-rate or variable-effort power steering is used on a growing number of vehicles. Variable assist is a way of providing the best of both worlds: finger-tip parking maneuverability at low speed, and reduced assist at higher speeds for greater stability and road feel.
What is variable pitch steering?
A variable-pitch racked bar has a row of rack teeth with a middle fixed pitch region and two end fixed pitch regions. A variable-pitch region is interposed between the middle fixed pitch region and each of the end fixed pitch regions.
How does a rack and pinion steering system work?
A rack-and-pinion gearset is enclosed in a metal tube, with each end of the rack protruding from the tube. A rod, called a tie rod, connects to each end of the rack. The pinion gear is attached to the steering shaft. When you turn the steering wheel, the gear spins, moving the rack.
What is variable-effort steering?
What is C factor in steering?
C-Factor C-Factor is the linear distance travelled by rack in one rotation of the pinion. To make steering system more responsive. The value of C-Factor should be as large as possible But, it should be kept in optimum range to keep the Pinion diameter in limit.
How do I know if my VW has variable ratio steering?
#Look at your Service Parts Identification label. If this pump stays in the same place even with an accelerated engine RPM, that means your vehicle is aided with variable-assist power steering. Furthermore, try checking out the area that remains under the lid of the trunk.
What is steer by wire?
Steer by wire A car equipped with a steer-by-wire system is able to steer without a steering column. The control of the wheels’ direction will be established through electric motors which are actuated by ECUs monitoring the steering wheel inputs from the driver.
What is the steering ratio?
Steering ratio is the main criteria while designing the steering system. It is nothing but the ratio of the number of teeth in the rack rod to the number of teeth in pinion gear.
What are the parts of rack and pinion steering mechanism?
Parts of Rack and pinion steering mechanism 1 Rack 2 Tubular casing 3 Pinion 4 Track rod 5 Ball and socket joint 6 Adjusting screw.
What is variable-ratio steering?
A variable-ratio steering, is a system that uses different ratios on the rack, in a rack and pinion steering system. At the center of the rack, the space between the teeth is smaller and the space becomes larger as the pinion moves down the rack.
Who invented the variable rack and pinion?
Arthur Ernest Bishop invented the use of a variable rack (still using a normal pinion) in the 1970s, to improve vehicle response and steering “feel,” especially at high speeds. He also created a low cost press forging process to manufacture the racks, eliminating the need to machine the gear teeth.