It's fascinating how far we have come from the old hand-operated windshield wipers to the advanced systems we have now. Modern wiper systems now operate at multiple speeds, intermittent function and can even clean windshields at upwards of 100 mph. But have you ever wondered what makes them work so well and rarely fail?
How Windshield Wipers Work
On the surface, how windshield wipers work may seem simple. But behind this simplicity lies a complex mechanism composed of various electro-mechanical systems and components.
The key parts of a wiper system are the wiper linkage, a DC electric motor, and the wiper arms that drive the windshield wiper blades. These major systems and individual assemblies all work together to ensure you have a clear view of the road in all driving conditions.
When you turn on the wipers using the switch on the steering column, an electric motor starts. This motor powers a mechanical linkage system that moves the wiper arms and blades back and forth across your windshield. As they move, the wiper blades sweep away any debris by pressing evenly against the glass. Your car may have different settings for the wiper speed. Basic models typically have a few speed options, while more advanced systems offer features like intermittent wiping and automatic rain-sensing to adjust to varying weather conditions.
Below we will briefly summarize the key components behind your windshield wiper system and how to maintain them for best operation and visibility performance over the life of your vehicle.
What Are the Components of a Windshield Wiper?
1. Wiper Motor
At the core of the windshield wiper system is a DC electric motor, typically found under the hood near the firewall that separates the engine from the passenger area. This motor generates a circular motion that is transformed by a linkage mechanism into a back-and-forth movement. This action moves the wiper arms and blades across the windshield. The motor is specially designed to work within a specific power range and at different speeds, ensuring that the wipers perform consistently, regardless of the season or the speed of the vehicle.
Wiper motors usually come with a vehicle warranty that lasts between 3 to 5 years, but they often last longer—over 10 years or even for the lifetime of the vehicle. However, wiper motors can still fail. Signs of wiper motor failure include louder motor noise, a slowdown in wiper speed, intermittent operation, or the wipers stalling or stopping during use, sometimes right in the middle of the windshield. If you notice any of these issues, it might be time to replace your wiper motor. As TRICO is a leading supplier of original equipment wiper systems, supplied to major vehicle manufacturers, we also offer a full portfolio of aftermarket wiper motors for both front and rear wiper systems
2. Linkage Mechanism
You might not see it, but there's a complex system of rods and levers hidden under the hood that helps your wipers move back and forth. This is called the linkage and plays an integral part in maintaining the relationship between the vehicle, wiper arms, and windshield. It takes the spinning motion of the motor and turns it into a sweeping motion for the wiper blades.
The linkage is also covered by your car's warranty for 3 to 5 years. But it can often last much longer, even for the entire lifetime of your vehicle. The linkage is built with strong metals and special plastics that can handle all the temperature ranges seen under the hood.
There are multiple linkage designs offered on vehicles based upon the size of the windshield:
- Tandem linkages operate with up and down motion in the same direction on both the driver and passenger side. On tandem systems, the pivot points are at the base of the windshield on the driver side and another pivot point at the vehicle's center.
- Opposed wipe systems have pivot points located at the base of the windshield, but one pivot is on the driver side and the other pivot is passenger side. The wiper system then operates in opposite directions so that a larger area of the windshield can be cleaned.
- Some linkages utilize a single articulating pivot that attached one wiper arm and blade.
3. Wiper Arm
The wiper arms are the component that connects the wiper module/linkage to your wiper blades. They serve as the bridge between the oscillating motion provided by the wiper linkage and your wiper blades back-and-forth action. Your wiper arms are unique to the driver and passenger sides and in most cases will exhibit discrete geometry (side bends, down form, and overall length) between the two locations.
There are three major features of your wiper arm:
- Attachment Point
- Spring
- Wiper Blade Connection (located at the end of your wiper arm)
3.1. Attachment Point
The attachment to the wiper linkage can often be hidden by a plastic beauty cover. However, your wiper arm will be attached to a threaded pivot shaft, secured with a nut that is fastened to a defined torque. In some cases, the nut can loosen and will not allow your wiper arm to travel back and forth. If you ever experience intermittent travel of your wiper arm or if your wiper arm stops between up & down motion, your wiper arm attachment nut may be loose. You can quickly tighten your wiper arm to the pivot shaft to maintain safe operation of your vehicle. Consult your vehicle owner's manual or local dealership service advisor to understand the proper torque to tighten or reattach your wiper arm.
3.2. Spring
The spring gives the wiper arm the required down force that is applied to your wiper blade. This down force is critical in maintaining the wiper blade contact in all-weather environments, at all vehicle speeds. The down force provided by the spring is specifically designed to match the wiper arm length, the blade length, and the contour of your windshield.
3.3. Wiper Blade Connection
The way wiper arms connect to the blades can differ depending on the make and model of the vehicle. These connection types are specified by the original vehicle manufacturer to ensure optimal performance and style with the wiper blades chosen at the time of manufacture.
When servicing your wiper blade, and installing your wiper blades to the wiper arm, it’s important to ensure that the blade is attached correctly per the wiper blade installation instructions. Failure to attach the blades correctly may cause poor wiping and reduced visibility.
4. Wiper Blade
While the entire system is important, wiper blades are the workhorses that determine if your windshield gets truly clean. They come in different shapes, sizes, and materials, each affecting how well they work and conform to your windshield. It’s important to select the proper construction and then to maintain the wiper blade over its useful life to have clear visibility while driving for the safety of you and your passengers. Getting the best performance from your wiper system requires regular maintenance of your wiper blades and serviceable components. The appearance of streaks or squeaking noises are clear signs you should replace your wiper blades.
When evaluating wiper blade performance, consider these five factors:
- Blade structure
- Rubber Squeegee
- Blade Attachment/Connection
- Aerodynamic Performance
- Contact Pressure
4.1. Blade Structure
| Conventional
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| Beam (Premium Performance Technology)
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| Hybrid
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| Rear
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4.2. Rubber Squeegee
The rubber squeegee is the part of the wiper blade that touches your windshield. The quality and shape of the squeegee, as well as the materials used, determine how well your wiper works. These materials include natural rubber, synthetic compounds, or a mix of both.
For instance, synthetic materials often deliver better resistance to extreme weather than natural rubber. However, natural rubber material offers a balance of durability, ozone and UV resistance, heat tolerance, with a naturally sustainable material versus synthetic materials.
TRICO manufactures both natural rubber, natural rubber & synthetic blends, as well as silicone squeegees for our wipers. The highly engineered materials selected in our products offer:
- Ozone resistance to protect the blades from hardening, drying out, and cracking, leading to a longer lifespan.
- Heat resistance to maintain blade flexibility, preventing chattering or skipping across the windshield in extreme summer heat.
- Friction-reducing coatings to minimize noise and extend blade life for lasting performance.
- Optimized blade shape for maximum windshield contact and clear visibility in all weather conditions.
4.3. Blade Attachment/Connection (Adaptors)
Most aftermarket wiper blades come with several adaptors to fit the original equipment wiper arms of your vehicle. Each adaptor is designed to match specific wiper blade and arm configurations. However, this variety of adaptors can make purchasing these blades confusing for consumers. Typically, most wiper blades include a pre-attached connector (usually a J-hook), with additional connectors packaged separately.
The TRICO Swift Lock connector system allows the consumer to connect to multiple wiper arms with the least amount of loose packed connectors. Also, adaptors designed for ease of installation must also ensure that the blade remains securely attached to the arm, resisting the forces of wind, rain, and the physical movement of the blade itself.
4.4. Aerodynamic Performance
At higher speeds, the wind and airflow over your vehicle can generate enough force to lift the wiper blade away from the windshield. This can be a problem, as it can impair visibility and make it difficult to drive safely. To address this, TRICO wiper blades employ an airfoil.
Airfoils are manufactured from engineered copolymer materials that are integrated into the wiper blade construction. Airfoils are located along the beam superstructure and their shape has been designed and tested to redirect the vehicle airflow. As air flows over your car, the airfoil redirects that air to press the blade down onto the windshield, keeping it firmly in contact for a clear view.
4.5. Contact Pressure
Fundamentally, windshield wipers must exert & maintain the right amount of pressure to remove all debris from your windshield without smudging your view or leaving streaks behind. The right pressure is achieved by developing the ideal beam blade shape for a wide range of vehicle and windshield shapes. As the force of the wiper arm is transferred to the wiper blade, it is important to manage the arm force to have a uniform contact pressure. TRICO Premium Wiper Blades utilize an exclusive twin point coupler design to improve the force transfer from the wiper arms to the wiper blade to optimize contact pressure. The TRICO twin point connector is 150mm (5.9 in) in length. This eliminates an exaggerated peak load in the center of the blade compared to other aftermarket blades. Also, the twin point connector requires less arm force to achieve & maintain optimum contact pressure during operation.
5. Fluid System
The fluid system comprises a reservoir or tank that stores the cleaning solution. A pump draws this fluid from the reservoir and directs it through hoses, which spray the fluid onto the windshield from a series of washer nozzles located on the hood, leaf screen or wiper arms.
Sometimes, the flow of fluid can be blocked if the nozzles are clogged or the hoses under the hood are worn or pinched. To keep your windshield clear, check the flow of washer fluid regularly. You can use a pin or needle to clean out or adjust the nozzles to ensure proper spray. Check this both while your car is parked and when you're driving.
If the washer fluid sprays weakly or you hear odd noises from the washer system, look at the washer pump. It might have a bad electrical connection or need replacing. If you need a new pump, TRICO Spray Washer Pumps match the original equipment quality.
You are now armed with the knowledge to understand how your wiper system operates and the importance of maintaining this critical safety system contained in your vehicle. Our hope is that with this consumer education you will choose TRICO for your next purchase.
