Snow or heavy rain being spread in front of your vision, or
Wiper lift when facing wind or at highway speed
These problems are very annoying or frustrating and could become dangerous in particular situations or when the driver is facing sun.
This is especially so when the sun is low in the sky in the morning or before night fall when we commute to work and the traffic is at its peak. Clear visibility is extremely important when driving. Vision is the sense mostly utilised when driving. No compromise on visibility should be accepted.
Why wipers do not clean well?
These frequent problems come from a very weak pressure applied on the wiper blade by the wiper arm. The arm and blade are pulled off the windshield by the air, creating a vacuum over them which is called air lift.
When we clean a surface of dirt, we have to apply some effort to detach this dirt on the surface. It is the same thing with wiper cleaning the windshield. Pressure must be present to obtain a good cleaning.
To make an analogy, it is like a jar, if you do not tighten the lid sufficiently, it will leak so it is the same with the wiper blade. You need to keep the blade tight to the windshield. The rubber or silicone part of the blade acts as a gasket and needs to be tight to prevent leaks.
Why these problems happen?
The bad cleaning problems come from the wiper arm original spring which is located within the wiper arm. The original wiper arm spring is pulling in a direction along the arm instead of applying pressure in the direction of the windshield.
Wiper arm have small thickness which gives the original spring a very small leverage to apply the pressure on the wiper blade.
The pressure applied by the arm is then far from being sufficient to achieve a good cleaning job and prevent air lift.
Aerodynamic, another factor
Fuel consumption is a large issue. To reduce it, car manufacturers lower the profile of vehicles to decrease the aerodynamic air resistance which is mainly responsible for all vehicles high fuel consumption.
This improved aerodynamic leads to slanting the windshield, thus enlarging the windshield size in height. This requires a longer wiper arm and longer wiper blades, which in turn, contributes to lower the pressure on the blade as this offers more wiper arm and blade to catch in the wind and create more lift and less pressure per inch of blade. It is still worst when the vehicle is at high speed or facing wind.
It consists of adding an external torsion spring to the wiper arm which adds an optimal pressure on the wiper blade for an unbelievable cleaning and to prevent wiper lift.