ELIMINATING BRAKE SQUEAL

At some angle, stiff sliding objects will naturally judder like chalk screeching on a blackboard, or chair legs groaning across a floor, or a brake squealing.


‍    “Brake noise… continues to be the single largest brake warranty item, even after many hundreds of hours are spent on both brake dynamometer and vehicle to eliminate brake noises for each new vehicle…”

Brake squeal is an intolerable, embarrassing noise, that OEMs must fix at their expense. 


Squeal is the result of the stacking of the individual manufacturing tolerances associated with:

‍ • calipers: piston, cylinder, slide-pins and holes, and attachment bosses and holes; 

‍ • pad backing plates: imperfect flatness;

‍ • discs: concentricity, axle-hub disc flange face and bearing bores;

‍ • vehicle: cast/machined caliper mounting brackets: lugs, bosses and bolt holes;

‍ • the jigs, fixtures, and tooling used in manufacture, and their changing condition with use;

‍ • final brake and vehicle condition at installation, damage, burrs and defects;

tolerances, that over millions, stack together at slight and different angles so every pad contacts edge-first and some at the squeal angle. If 0.1% are squealers, 1000/M brake warranties will cost OEMs millions.


One common attempt to fix squeal is chamfering, where friction is ground away reducing contact area which reduces brake performance/safety, but not squeal. Chamfering also: increases pad wear (from reduced pad volume), creates more toxic brake dust (from faster wear), and results in brakes too big and heavy for what is functionally a smaller pad. Unneeded weight reduces EV range, fuel economy, performance, and handling. 


Shims are another no-fix (8 per car), that cost OEM’s more millions. 


The only solution to brake squeal is the no-cost “NuPad”. 


NuPad has a very slightly raised centre (Fig 1) that contacts the disc first allowing the angled pad to tilt slightly which eliminates its squeal angle and wearing parallel to the disc. That simple, Saves millions.


NuPad has a very slightly raised friction centre (Fig 1) that always contacts the disc first thereby allowing the angled pad to tilt slightly to the caliper-piston angle and wear parallel to the disc eliminating  the squeal angle. That simple, Saves millions.   


With no chamfers NuPads are safer, make less dust, are cheaper, quieter, longer lasting, and lighter.

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In addition, NuPad is a ‘no-cost’ solution. On a standard brake grinder two slightly angled flats, or facets, are ground from the pad centre to each end at about a 0.1 degree / 0.010” / 0.2 mm slope, to create the required imperceptibly higher contact centre. It can be done in one pass using two angled grinding wheels (pat pend). A four faceted shallow pyramid face and other rounded, raised centre geometries can also work.


A method has been devised to validate this squeal hypotheses.


The NuPad recent patent application is for sale with world coverage available.

Get first-to-market advantage, rights to sub-license and decades of huge earnings from a small capital outlay.


Contact: Winston MacKelvie, Inventor, (*90 IPs). 

winstonworks@me.com Tel 1-450-243-6850 Txt 1-450-330-4293 

www.inventure.ca

Some Background


“Brake noise, even for vehicle manufacturers, continues to be the single largest brake warranty item, even after many hundreds of hours are spent on both brake dynamometer and vehicle to eliminate brake noises for each new vehicle platform,” observes Bob Peters chief engineer, friction material engineering with Akebono Brake Corporation. “The fact is that brake noise is nearly impossible to simulate on the computer and, consequently, most noise mitigation work is done on actual parts, using both special noise dynamometers and on the vehicle. This is expensive and time-consuming.” [and unsuccessful]

‍    https://thebrakereport.com/aftermarket-search-quieter-brake/ 

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Inventor’s early rough R&D; Easily reproducible


A.  New, painted white and installed. 

B. After a few brakings. Wear way off-centre - a recipe for judder-squeal NHV.

C.  Same pad made into a NuPad, repainted used, showing flat centred wear.

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Quotes:

“In the last few decades, there have been extensive studies on analysis and investigation of disc brake vibrations done by many researchers around the world on the possibility of eliminating brake vibration to improve vehicle users' comfort. Despite these efforts, still no general solution exists.”

‍    https://www.researchgate.netpublication258725751


“Friction-induced vibration and noise emanating from car disc brakes is a source of considerable discomfort and leads to customer dissatisfaction. The high frequency noise above 1 kHz, known as squeal, is very annoying  and very difficult to eliminate.” 

‍    https://www.researchgate.net/publication/258994745_Recent_Studies_of_Car_disc_Brake_Squeal

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“New Jersey lawsuit claims genuine Audi replacement brake pads and rotors are defective on Q7 model.

Audi Q7 squeaky brakes have caused a class-action lawsuit filed for all New Jersey  citizens who had brakes installed by Audi dealers between July 19, 2012, to the  present.”

“BMW was hit this week with a class action lawsuit over excessive brake squeal. In July, we reported that a similar law suit against Audi was settled.” The Brake Report Aug 8 2021

‍ Media News  

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“In the last few decades, there have been extensive studies on analysis and investigation of disc brake vibrations done by many researchers around the world on the possibility of eliminating brake vibration to improve vehicle users' comfort. Despite these efforts, still no general solution exists.”  

www.researchgate.netpublication258725751 


“…. I hate brake squeal, I actually have an existing noise on my truck, tried 2 sets of different pads and rotors front and back and still can’t get rid of the noise!”

‍    J. Dutton, Florida, Auto parts sales