I found this looking for Formula 1 braking systems, and it seemed to me that it could be an improvement and/or replacement for the traditional braking system with 1 brake rotor per hub, or 2 per axle. This specific brake system uses 2 rotors for each hub, or 4 per axle. Thus doubling the overall friction surface. And it also gives the ability to decrease the size of each rotor/disk,by up to 25mm, for a decrease in unsprung weight, and eliminates the need for larger sized wheels (road cars) when considering upgrading or using "higher" performance brakes. Besides offering good performance and reliability, as stated in the article, it offers a new and interesting alternative to the traditional system used in modern vehicles, both road and race.
I hope to see it come into the production car market, or even into the racing market, as it would be rather interesting to see if holds up to the conventional competition, or maybe even takes it by storm and gives a higher level of performance.
When clicking on the link it asks you to register to the website, but you dont have to the first time i believe, only when returning for the second time to the article. So i just copied the article on to here.
Engineerlive.com
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"New disc braking systems deliver automotive benefits
Vast sums of money are spent on developing machinery that goes faster, but it has to be remembered that unless a process runs at a constant speed, overall cycle time can also be reduced by improving the stopping time.
The same is true for automobiles: better braking is just as important as better acceleration.
Disc brakes are a significant improvement over drum brakes and antilock braking systems (ABS) deliver increased safety. Nonetheless, manufacturers of braking components are still hard at work developing further improvements, some of which are more radical than others.
Take Delphi automotive, for example, with its twin-floating-disc braking technology, known as the Delphi Maximum Torque Brake (Fig. 1). Advantages are claimed for thermal management, weight, packaging and NVH (noise, vibration and harshness).
"The traditional solution to coping with increasing vehicle weight and performance is to up-rate conventional braking systems, including larger discs (often forcing larger wheels) and advanced materials, but this is a costly solution that has a negative impact in many other areas of vehicle engineering," explains Chris Baylis, director of engineering at Delphi's Leamington innovation centre, UK.
Maximum Torque Brake uses two discs floating on the outside diameter of the hub. A hydraulically actuated piston applies braking force via pads that operate on the outside and inside faces of each disc, providing four friction surfaces. The new technology can therefore provide up to 1.7 times the torque output of a conventional single disc system of the same effective diameter, or similar torque from a reduced diameter. Wear and serviceability are said to be equivalent to today's traditional product and the floating disc architecture should eliminate problems with lateral run-out.
The twin disc design also provides four cooling surfaces, without the need for vanes or cooling channels, thereby substantially reducing thermal stress on the brake and hub-mounted components. This improved thermal management provides engineers with many options for enhancing other aspects of the braking system. By increasing the opportunities to optimise the combination of disc size, pedal travel, booster size and friction material, Maximum Torque Brake allows the feel, cost and performance of the system to be precisely matched to market requirements.
For example, with four pad surfaces, Maximum Torque Brake requires approximately half the apply pressure of a conventional disc brake. This could be utilised to significantly downsize the vacuum booster or to reduce the pedal effort and travel. A downsized booster could reduce weight by up to 1kg and provide more premium under-hood (bonnet) space to improve packaging flexibility. Alternatively, disc diameter could be reduced by up to 25mm, allowing smaller wheels (which can generate a substantial cost saving), higher aspect ratio tyres (important for off-road vehicles) and a significant reduction in unsprung weight.
Reduced warranty claims
The superior thermal management of Maximum Torque Brake and its minimal generation of disc thickness variation (DTV, caused by the discs wearing unevenly) also provide excellent NVH performance. This helps to solve the potentially significant problem of noise-related warranty claims, which surveys show is a major consumer issue in the USA and the cause of significant warranty costs. "Because the discs are floating on the hub, their contact with the pads is always even. Maximum Torque Brake does not have the wear issues or the tolerance stack-up that can cause judder and squeal in conventional systems," explains Baylis.
Other benefits of the system include reduced brake fade and, due to the reduced apply pressure, shorter stopping distances in the event of a vacuum failure - a homologation requirement that can be increasingly challenging to meet using conventional, highly-boosted systems.
Delphi's claims for the performance of the system are borne-out by testing to the independent AMS (Auto Motor und Sport) standards using a BMWX5 fitted with the system. In the 12-stop test, which is increasingly seen as a European standard, the vehicle demonstrated an exceptional 'no fade' performance.
Delphi's testing indicates that in a typical
high-performance SUV (sport utility vehicle) application, Maximum Torque Brake will reduce the maximum operating temperature by more than 100ûC, improve refinement and offer either reduced pedal travel by up to 25mm (due to the reduced volume of fluid required for actuation) or booster downsizing by around 40mm. Total vehicle weight saving could be as much as 7kg, depending on system specification and the level of integration.
So far the system has completed more than 1.5million test kilometres in 20 vehicles to help ensure that it will continue to perform to specification in any terrain or usage pattern, throughout a vehicle's life
(Fig. 2). Two fully engineered implementations have been shown to vehicle manufacturers: one fitted to a
B-segment small European car, the other on a large high-performance SUV. The former has the piston integrated within the suspension knuckle while the latter demonstrates a standalone piston architecture that could be implemented as part of a mid-life model upgrade.
Maximum Torque Brake can be manufactured using existing materials and processes and Delphi has striven to make further reductions in cost and complexity. An example is the wheel hub on which the discs are mounted, which is neatly designed as a one-piece unit into which the wheel bearing can be press-fitted. Future developments will introduce additional lightweight materials, leading to further weight savings.
Analysis program
To help vehicle manufacturers implement Maximum Torque Brake, Delphi has also developed a suite of computer-based analysis programs that model a range of extremely vigorous whole-vehicle tests. This allows a designer to quickly optimise the combination of benefits achievable with the system.
Maximum Torque Brake can be supplied as a separate product or can be integrated with complete vehicle corner modules and supplied using the latest SILS (supply in line sequence) techniques. It can also be integrated with other systems from Delphi's portfolio of electronically controlled brake technologies, including the latest Traxxar enhanced stability program, or with equivalent systems from other suppliers. Indeed, the need to provide fast, powerful, high-resolution brake activation for these systems is one of the factors that Delphi believes will drive the adoption of the system.
"Conventional brakes struggle to react against the torque of increasingly powerful engines, so stability programs have to be calibrated to shut the engine down early at the expense of refinement and driving pleasure," explains Baylis. "Maximum Torque Brake will allow vehicle manufacturers to make the operation of these systems more transparent."
Delphi says that discussions with vehicle manufacturers are progressing well and that the system could be in production by 2006."
http://www.engineerlive.com/european-de ... fits.thtml
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