With the image flying around the Internet of a possible prototype Shimano hydraulic brake system for road bikes, the timing on their patent filing couldn’t have been better for feeding the rumor mill.
The photo above is just one of many included in a February 7th US Patent Application describing a “bicycle component control device (that) includes a bracket, a hydraulic brake unit and either a mechanical or electronic shifting unit.” The rest of the initial description reads:
“The bracket has a gripping portion. The hydraulic brake unit is operatively mounted on the bracket and configured to operate a hydraulic brake device. The mechanical shifting unit or electric control unit is operatively mounted on the bracket and configured to control a bicycle device.”
It’s worth mentioning that all major companies patent all sorts of things that never come to fruition, but what’s really interesting is this isn’t Shimano’s first hydraulic brake patent filing…
Back in July 2007, Shimano filed a patent application for a “Multi Position Brake Lever System With a Converter That Converts aCable Actuator to a Hydraulic Actuator”, shown above. It’s described as “a hydraulic assembly for a hydraulic disc brake system that includes a housing defining a cylinder, a piston received in and moveable within the cylinder, a first lever operatively associated with one of the piston or the cylinder, and a second lever operatively associated with the other of the piston or the cylinder.”
Here’s a view of the hose and cable entry/exits on the side of the converter. This application was published in January 2009 and would have preceded TRP’s Parabox and the others by a good bit.
Shimano also filed a patent application in August 2009 for a “Hydraulic Brake Control Unit” that, to us, looks an awful lot like a TT brake lever. Here’s the internals:
Sure beats the Magura RT6TT to the punch, no?
And then there’s this hydraulic rim brake design patent filing for a “Hydraulic Connector Arrangement”. At first, I thought this was pre-STI based on the design of the brake lever and the hose exit port, but no: This was filed in December 2009 and published in June 2011! Could this mean a hydraulic rim brake is coming, too?
BACK TO THE FUTURE
At the top of this post are the drawings for the Mechanical shifters with integrated hydraulic master cylinder. Above is presumably the Di2 version as the diagram essentially matches the layout and size of the small electronic shifting controls.
One interesting bit to point out is the higher position of the brake lever pivot. On the standard (mechanical brake) STI levers, the brake lever’s pivot is about where the piston enters the hood. The lever feel could be quite different as a result, but with all the attention Shimano paid to the current 9000 group’s brakes, our bet is it’ll perform quite well.
Where some of the older patents use pretty descriptive names, this one’s simply called “Bicycle Component Control Device”.
How does this compare to SRAM’s upcoming hydraulic road brakes? Without that product being officially launched, no one has hard details, but images suggest some or all of the master cylinder may be placed inside the forward knob given it’s pronounced growth over its mechanical counterpart. If that’s the case, it’s likely because SRAM’s shifting mechanics are larger than Shimano’s, which might have forced the design. Or, they could have been avoiding conflict with Shimano, who’s patent describes the master cylinder as “located rearward of the pivot axis of the operating member.” While SRAM announced their hydro units first, Shimano’s patent is a divisional application of an original patent filing from 2011 that may have spelled out some iteration of this prior to SRAM’s designs.
Subtle but important details that we look hope to confirmed in the real world soon!
JUST FOR FUN
Shimano Di2 powered dropper post anyone? Thanks to one of our readers (What up, Varaxis!), we got these images of another of Shimano’s patent applications: The “Motorized Bicycle Seatpost Assembly.”
The diagrams show the computer control unit under the saddle (26) and the battery inside the top of the post (68) driving a motor attached to a screw-type set of gears to raise or lower the seat via a switch on the handlebars. This one was filed in August 2009!
