Mercedes’ Monoblade Wiper
I’ve been captivated by this thing ever since I was a kid. Is there any more fun car activity on a dreary, drippy Tuesday afternoon ride home from school than trying to find a mid-’80s Mercedes E-Class or 190E just to catch a glimpse of the wiper in action? There is? Well… I enjoyed it.
Attempting to achieve a cross between the coverage of two blades and the economy and aerodynamic advantages of a single blade, Mercedes’ Monoblade (also known as “eccentric clean sweep”) certainly wasn’t the first single wiper system on the market. Cars as varied as entry-level Fiat econoboxes, sporty VW Sciroccos and high-end Jaguar luxury sedans preceded it with their solitary blades. What made the German automaker’s wiper system unique was the hub mechanism used to increase the wiper’s coverage of the windshield beyond a simple arc.
As illustrated above in the “single arm (controlled)” drawing, the Monoblade’s substantial coverage was achieved by designing it to extend outward toward the corners of the windshield in the course of its travel across the glass. A cam-type device in the hub moved the arm away from the pivot twice, retracting it in between so the wiper would not overextend the top of the windshield. It all sounds ungainly, but to watch it in action is to witness a quasi-mesmerizing symphony of mechanical fluidity. Call it odd, but I’m transfixed whenever I see a Monoblade going through its paces on a rainy day. I nearly have to wrench my attention away from the spectacle in order to focus on the task of driving my car.
Introduced on the pioneering W201 190E model series and also fitted to the W124 and W210 E-Class generations as well as the W202 C-Class, the Monoblade’s primary advantage was aerodynamic, as it noticeably cut wind resistance at high (read: Autobahn) speeds. Even though it seemed more simple, with one linkage instead of two, as in a traditional wiper system, the Monoblade was actually more expensive to produce and repair, owing to the number of specialized parts. Additional disadvantages included the difficulty for owners in finding the required long replacement blades and a slight, but decidedly non-luxurious rocking motion introduced to the car when the big wiper was operating in high-speed mode.
Watch the clip below to see the wiper in action, and be on the lookout for an older C- or E-Class next time it rains. You’ll get a treat.
Editor’s note: This post is part of an ongoing series spotlighting obscure automotive engineering solutions. Read the other installments here: