1.Full area wiper system
The full area wiper is equipped to keep the specified wiping area independently of the wiper speed.
In the normal wiper system, the wiping area is apt to become larger because of the inertia by the wiper speed when the wiper operates at high-speed. The wiping area is set taking this into consideration. As a result, the wiping area becomes small, that is, the remaining area becomes large when the wiper operates at low-speed.
The full area wiper automatically makes the wiping area smaller/larger to reduce the remaining area at low-speed.
In the full area wiper, the full area wiper motor is located beside the normal wiper motor and the position of the wiper link mechanism is changed. In this construction, when the full area wiper motor operates the worm gear turns and then the wheel gear turns. As a result, since the idle lever operates, the position for the wiper link mechanism varies.
Wiper switch INT, LO position
The wiper control unit makes the full area wiper motor rotate normally to the LO position, the center position of the idle lever varies (a to a’) and the fulcrum varies (b to b’, c to c’) at the same time. As a result, the wiper blade moves from the storage position to the LO position. After that, the wiper performs intermittent or low-speed operation.
Wiper switch HI position
2.Vehicle speed-sensing, adjustable interval INT function
This function controls the interval time of the wipers in accordance with the vehicle speed when the wiper switch is in the INT position.
The interval time adjusting range consists of 3 steps, which can be selected by operating the interval adjuster.
The interval time can be controlled with no step within each range.
3.Vehicle speed switching function
This function that automatically switches to the intermittent operation when the wiper switch is in the LO position and the vehicle is stopped.
To perform this function, the stopping and driving conditions of the vehicle are determined as described below.
Driving judgement
When the vehicle speed is other than 0 km/h (0 mph), or the stop light and the parking brake are OFF and the shift lever is in a position other than “P” or “N”.
Stopping judgement
When a condition other than the driving judgement has been detected.
When the vehicle is stopped, operating the wiper switch from the INT or HI position to the LO position causes the wipers to operate 3 times at the low-speed, and then automatically switch to intermittent operation with an interval time of approximately 2.5 seconds.
When the vehicle is being driven and the switch is in the LO position, stopping the vehicle causes the wipers to operate twice, and then switch to intermittent operation with an interval time of approximately 2.5 seconds.
4.Washer-linked wiper with drip-preventive function
With this function, when the wiper is in the OFF or INT position, turning the washer switch ON for approximately 0.2 seconds or longer causes the washers to operate, and after the washer switch has been turned OFF, the wipers operate in unison 3 times at the low-speed.
Approximately 3 to 7 seconds, depending on vehicle speed, after the low-speed operation of the wipers has been completed, the wipers operate once again to wipe off the washer fluid that has dripped.
5.Raindrop sensing function
When the wiper is in the AUTO position, this function uses a rain sensor that is mounted on the windshield glass to detect the amount of raindrops, and controls an optimal wiping timing accordingly.
The rain sensor consists mainly of an LED (Light Emitting Diode) that emits infrared rays, and a photo diode that receives those rays.
The detection method is based on the infrared rays that are reflected by the windshield glass.
For example, if no raindrops are present in the detection area, the infrared rays emitted by the LED are all reflected from the windshield glass and are received by the photo diode. Rain sensor tape fills the clearance between the lens and windshield glass.
If raindrops are present in the detection area, a portion of the emitted infrared rays penetrates with the change of index of reflection outward of the windshield glass via the raindrops, thus reducing the amount of infrared rays that are received by the photo diode. The amount of this reduction is then used to detect the amount of rain drops.
Thus, this function controls the intermittent, low-speed and high-speed operations in order to operate the wipers at an optimal wiping timing.
Fail-safe
If the wiper control unit has determined that a malfunction has occurred in the raindrop sensing function, it operates the wipers intermittently in accordance with the vehicle speed, as a fail-safe function.
Also, the wipers can be operated normally by the wiper switch in the LO or HI position.