Published on September 30th, 2019 | by Carolyn Fortuna0
New Tesla Patent: An Electromagnetic Windshield Wiper System
September 30th, 2019 by Carolyn Fortuna
Way back in 2014, Tesla CEO Elon Musk wrote a blog post about a wall in the Palo Alto headquarters lobby that proudly displayed a list of Tesla patents. It was being removed. Due to “the spirit of the open source movement, for the advancement of electric vehicle technology,” the company would not protect patents that seemed to serve no purpose other than to “stifle progress, entrench the positions of giant corporations, and enrich those in the legal profession.”
Fast forward 5 years, and today Tesla builds not only all-electric vehicles, but also scalable clean energy generation and storage products. Tracing the company’s timeline of innovation includes acknowledging the numerous Tesla patent applications that have gone before the US Patent and Trademark Office. Sometimes, the ideas are for brand new products; at other times, the Tesla patents target a familiar item conceptualized with a new flair or efficacy. The latter is the case with the newest Tesla patent — an electromagnetic windshield wiper system.
Published on September 5, 2019, Tesla’s patent filing for the electromagnetic windshield wiper system contains the following specifications:
- a linear actuator with at least one guide rail having permanent magnets and an electromagnetic moving block;
- wiper arrangement which includes a wiper arm and a wiper blade, with the wiper arm coupled to the electromagnetic moving block; and,
- control circuitry which manages a linear motion of the electromagnetic moving block along at least one guide rail to steer the wiper arm that is coupled to the electromagnetic moving block back and forth across a length of the windshield to the windshield, so that the electromagnetic moving block induces minimal friction during the linear motion.
Why Conventional Windshield Wipers Aren’t Adequate for New Generation EVs
The United States is a “first to file” nation, which means that in order to be entitled to a patent in the United States one must file a patent application prior to information about a technology being disclosed. The Tesla patent for the electromagnetic windshield wiper system offers background information about the need for redesigned windshield cleaning systems.
Squeaky clean: The patent states that, because conventional windshield wiper systems use multiple wiper blades, they usually have a cluttered design and do not sufficiently clear the windshield, which may hamper the unobstructed field-of-view of the road ahead.
Misplaced power needs: The patent application explains that many conventional wiper systems use electrical motors to move one or more wiper blades to clean a windshield of a vehicle. With many mechanical components, such as gears and bearings, to slide the wiper blades, the resulting sliding motion creates significant friction. That means that additional power is required by the in-vehicle battery, which decreases EV range.
System deterioration: As gears and bearings of conventional systems rust and wear, their cleaning efficiency decreases, especially in geographical areas with significant annual rainfall or snowfall. Corrosion decreases effectiveness and adds risks.
Windshield design: The curvature of windshields has become more complex over the years, and now conventional wiper systems have difficulty adapting to varying surface profiles. That means their ability to effectively clean windshield contaminants is frequently compromised. Windshields that curve around a driver aren’t fully cleaned any longer. Also, conventional wiper systems have varying influence from aerodynamic effects as they traverse from the bottom of the windshield to the top and vice versa, due to airflow vector changes.
Why the Tesla Electromagnetic Windshield Wiper System is an Improvement
The proposed Tesla electromagnetic windshield wiper system works using electromagnets and guide rails with a single-blade design. The length of the wiper arm blade is in contact to the windshield to wipe the defined region of the windshield based on the linear motion of the electromagnetic moving block.
The control circuitry is configured to stow, using the rotational actuator, the wiper arrangement beneath a hood of the vehicle by adjusting an inclination angle of the wiper arm with respect to a reference axis. The electromagnetic wiper system adjusts an angle of attach with respect to a reference axis during the linear motion. The control circuitry is configured to adjust the angle of attach of the wiper arm based on a detected weather condition.
The significant change in the Tesla electromagnetic windshield wiper system means that, instead of using simple recirculating electric motors, Tesla’s design mounts the wiper arms to electromagnetic guide rails. These function more easily than conventional wipers due to reduced friction and a wider expanse of the window covered by a reconfigured wiper sweep.
This all shakes out to mean that the Tesla electromagnetic windshield wiper system would draw less power from the car’s battery, as electromagnets are frictionless. Autonomous driving was a consideration in the patent language, too, as the Tesla Autopilot system would not have to concede any longer to corrosion from time and weather conditions. Better visibility is a plus for the cameras and, of course, for the driver.
The Origin of the Windshield Wiper
Inventor J. H. Apjohn came up with a method of moving two brushes up and down on a vertical plate glass windshield in 1903. In the same year, Mary Anderson devised a swinging arm that swept rain off the windshield when the driver moved a lever located inside the car. Anderson patented her invention of the mechanical windshield wiper in 1905, and it became standard equipment by 1913.
Today’s windshield wipers are little more than a small gear set that rotates back and forth and pushes the wiper blade across the windshield. The contact between the blade and the windshield has been a site of constant updating, and that’s exactly the area on which Tesla is focusing with its new patent.
J.H. and Mary, the next-generation windshield wiper systems are ready to leave your ideas behind in the dust. We’ve come to a moment in time in which the Tesla electromagnetic wiper system will not only be cleaner and provide a better view for driver or autonomous cameras — it will be configured to “communicatively couple” to another control unit via the in-vehicle network.
Yup. Your Tesla windshield wipers will be Smart wipers.
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