Wiper system for a vehicle

A wiper system for a vehicle, comprising:

• a first wiper device comprising:
• a quadric linking mechanism which includes:
• a main lever connected to a pivoting shaft located in a vehicle body and pivotable with said pivoting shaft, said main lever being rotatable through a rotation angle;
• a sub-lever pivotally supported by a spindle located in said vehicle body at a predetermined distance from said pivoting shaft;
• an arm head having an end portion of said main lever pivotally connected thereto via a first connecting shaft and having an end portion of said sub-lever pivotally connected thereto via a second connecting shaft;
• and
• a wiper arm connected to said arm head and having an end portion of a wiper blade connected thereto, said wiper arm being pivotable through a predetermined angle in accordance with the pivotal movement of said main lever thereby providing a wiping range for wiping a surface;
• said wiping range being enlargeable by an expansion length of said wiper arm by operation of said quadric linking mechanism;
• and
• the expansion length of said wiper arm being the sum of distance “a” between said pivoting shaft and said first connecting shaft and distance “b” between said first connecting shaft and said second connecting shaft, minus the distance “e” between said pivoting shaft and said second connecting shaft when the device is in its at-rest position;
• wherein said distance “a”, said distance “b”, distance “c” between the spindle and said second connecting shaft, and distance “d” between said pivoting shaft and the spindle are such that a range of angular velocity of rotation of said wiper arm is from 0.75 to 1.25 times the angular velocity of rotation of said main lever at any point in the wiping range of said wiper arm.