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Rotor patent application shows single-lever, one-way mechanical and hydraulic shifting

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rotor one-way shifter lever with mechanical and hydraulic derailleur patent application drawings on Bikerumor-com

While it would seem SRAM managed to skirt around Shimano and Campagnolo patents to create the only remaining (or at least feasible) solution, Rotor may have come up with something different. It does acknowledge that SRAM’s single direction/single lever design is in the same vein as what’s shown here, but they bring a new twist to it: Multiple levers operating a single derailleur (think brake lever shifters and TT bar end shifters working together) without electronics. It also claims to improve the reliability and precision of mechanical shifting while also reducing system weights. Oh, and it could be cheaper.

And, ideally, it could all be done hydraulically. Interested?

rotor one-way shifter lever with mechanical and hydraulic derailleur patent application drawings on Bikerumor-com

In it’s most elegant implementation, Rotor’s proposed system moves the ratcheting and release system into the derailleur body. Typically, these parts are in the shifters, which is what allows for indexed shifting and for one lever to pull the cable and the other to release. Or, in SRAM’s case, for a single lever to do both using different stroke lengths. That same movement system is used here – a short stroke creates a downshift, and a longer push creates an upshift. The difference is, Rotor would prefer to do it hydraulically and move all of the moving parts down to the derailleurs.

This would be a big departure from ACROS’ system shown a couple years ago. That one put a master cylinder on the lever and required pushes in different directions and two hydraulic lines running between each shifter and derailleur. Besides a much smaller shifter unit, putting the ratcheting mechanism on the derailleur would allow multiple shifters to operate a single derailleur. It would also increase reliability, offering crisper shifts…particularly with mechanical cable-driven shifters, but we’ll get to those in a minute.

Let’s start with hydraulics, since the patent application calls it the preferred embodiment of the design. As shown in Figure 15 (top of page), a simple hose splitter is all that’s needed to add more than one shifter lever. Each shifter would simply push a little or a lot of fluid depending on how far it was pressed.

rotor one-way shifter lever with mechanical and hydraulic derailleur patent application drawings on Bikerumor-com

For the front derailleur, that fluid would enter a slave cylinder (111), pushing the piston (112) outward. The piston moves a geared rack (113), which turns the pinion (114), driving the main shaft (4) to actuate the ratcheting mechanism (13) inside the main body.

rotor one-way shifter lever with mechanical and hydraulic derailleur patent application drawings on Bikerumor-com

Alternately, Figures 3A/B/C shown another layout, still relying on a rack and pinion system (same numbers and items correspond between Figures 2 and 3).

rotor one-way shifter lever with mechanical and hydraulic derailleur patent application drawings on Bikerumor-com

And Figure 4 (up top) and Figure 10 show another way it could work:

 

rotor one-way shifter lever with mechanical and hydraulic derailleur patent application drawings on Bikerumor-com

Figure 10 is a closeup detail of the design shown in Figure 4. Here, the fluid pushes ratcheting mechanisms downward. Presumably, a short push moves the parts to catch on the first set of teeth on the ratchet gear (1) and a longer push activates the release mechanism (6, 7) to undo the lock (3) and let the derailleur shift back down to the smaller chainring. Two sets of teeth in both the upper and lower positions suggest trim adjustments might be incorporated.

rotor one-way shifter lever with mechanical and hydraulic derailleur patent application drawings on Bikerumor-com

The rear derailleur drawings don’t show specific hydraulic designs, but they share a similar ratcheting section (13), except it has more teeth to account for the increased number of gears it’s responsible for catching. Presumably, a similar hydraulic slave cylinder/piston/rack/pinion system would be used to actuate the ratcheting mechanism here, too.

rotor one-way shifter lever with mechanical and hydraulic derailleur patent application drawings on Bikerumor-com

Figure 7 shows the internal workings of the ratchet mechanism, using a rack (81) and pinion (82) system to drive the main shaft (4). As the gears are shifted upward, the lock element (2 and 21) catches the teeth on the ratchet gear (1). The ejector element (6) releases the locking element when it’s time to let it move in the other direction.

rotor one-way shifter lever with mechanical and hydraulic derailleur patent application drawings on Bikerumor-com

Figure 8 shows a single shift action along the ratcheting gear. Moving chronologically from T01 to T08 shows what’s likely a shift to an easier cog, where the drive element (3) pushes the ratchet gear to rotate it while the lower locking element (2) slips over one ratchet tooth. Then, as the shift lever is released, the drive element (3) returns to its starting position. (This is our guess based on the drawings and description). A larger push on the lever would likely release both to let it slip back one notch.

rotor one-way shifter lever with mechanical and hydraulic derailleur patent application drawings on Bikerumor-com

Figure 11A shows a single shift lever for the hydraulic systems. The lever moves the piston (312) into the master cylinder (311) to push fluid into the hose leading to the derailleur (115). The drawing suggests a flat bar lever design, which could mean mountain bike options as well as road. Below it is an example of a mechanical lever equivalent.

rotor one-way shifter lever with mechanical and hydraulic derailleur patent application drawings on Bikerumor-com

The drop bar hydraulic shift lever incorporates a similar piston-into-master cylinder system to actuate the shifts, using a second paddle behind the brake lever to control shifting. This one shows a hydraulic brake system on board, too, all in a compact package.

The hydraulic system saves weight over a comparable mechanical system simply by nature of the materials used: plastic hoses and lightweight fluid. The mechanical system, shown below, saves weight because it no longer requires heavy, strong steel cables to perform the shifts since all of the ratcheting hardware is on the derailleurs. Instead, the application claims they could use lighter synthetic strands to actuate the derailleur.

MECHANICAL SHIFTING DESIGNS

rotor one-way shifter lever with mechanical and hydraulic derailleur patent application drawings on Bikerumor-com

The mechanical, cable driven design also puts all of the ratcheting at the derailleurs. For a single shift lever design, this could mean drastically crisper shifts for years without concern for cable stretch, dirt, or gummed up lube or cable housing. For double lever systems, well, it’s rather novel and it’s shown on the right in Fig. 17 (Figure 16 shows an alternate design for hydraulic systems using two levers using a hose splitter but putting the ratcheting mechanism inline on the downtube rather than on the derailleur. This is likely shown only as an option to broaden the scope of the patent as it’s certainly much less elegant than the full enclosed designs shown prior).

Figure 17 shows how a dual mechanical system would work. Each shift lever would feed a single cable to the splitter (not numbered, but shown in closeup). Regardless of which shift lever was pushed, the splitter would be pulled away from the derailleur, pulling the drive cable (123) and actuating the derailleur.

rotor one-way shifter lever with mechanical and hydraulic derailleur patent application drawings on Bikerumor-com

On the derailleur, the main shaft is rotated by the cable’s pull rather than a hydraulic push, but otherwise operates the same.

rotor one-way shifter lever with mechanical and hydraulic derailleur patent application drawings on Bikerumor-com

The mechanical lever combines the shift and brake levers into a single unit, passing the brake cable straight through the center of the cable’s master pull (321).

Whether either system ever sees the light of day remains to be seen, but rest assured we’ll provide all the tech details if/when it does.

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34 Comments
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AlanM
AlanM
8 years ago

Ahh yes, I’ve always thought my derailleur reliability would be increased by adding more moving bits and pieces.

Slow Joe Crow
Slow Joe Crow
8 years ago

That reminds me, whatever happened to Acros’ hydraulic shifting MTB group? That actually hit retail sales a few years ago.

Francois
Francois
8 years ago

To me the main question remains: what problem are they trying to solve?

Overall reliability? Sticky/streched cables are no longer of problem, but as AlanM pointed out, the derailleur itsefl might be less reliable than a conventional one, so I’m not sure it would overall perform better in bad conditions.

Multiple levers for the same derailleurs? Electronics fixed that, and I think it’s mostly an issue for TT/triathlons.

But the downside is that it completly breaks compatibility with other systems. Hydraulic shifting would even need different cable stops, so would not be compatible with current frames (or you would need zip ties).

JBikes
JBikes
8 years ago

come on guys, the shift action will be so fluid…

me
me
8 years ago

I agree on hydraulics for shifting…but I question why so many moving parts? all those gears if exposed would likely be a problem with dust and mud….so would eliminate the reliability.

j
j
8 years ago

wild…

does anyone remember the pneumatic shifting for downhill bikes a decade or so back?

CS
CS
8 years ago

Now I am no expert, but in theory, if you were in a CX race, or any for that matter and you crashed and the bike was upside down for even a few seconds, could it get enough air in the lines where the bike may not shift like you want it until the air works its way out several minutes later?

CH
CH
8 years ago

While having shifters on the base bar of a TT bike is cool and super useful.. I don’t know if it is worth having this complicated of a set up to make it happen. Its pretty easy to just reach out to the shifter and flick it

Antipodean_eleven
8 years ago

Hmmm. Well, interesting. Have to agree with @Francois, it does not seem to solve any particular problem and indeed makes things more complicated. I sorta feel the same way for electronic for 99% of riders as well but see it at least offers performance improvements for those truly fast enough for those small improvements to matter.

Shanghaied
Shanghaied
8 years ago

@CS, why would it? It’s not like hydro brakes lose brake power when the bike is upside down.

I think the complexity will drive up cost so much as to be impractical, just like the Acros system. While I think the there could be a good argument for hydraulic shifting for offroad use, since sealed hydraulic lines will likely be much more resistant mud and dust than cables, the benefit will probably negated by the super complex derailleurs.

booyah
booyah
8 years ago

CS- If the hydraulic lines were that vulnerable to air entering them, they wouldn’t work, period. Hydraulic brakes are typically fine if the bike has been stored upside down, so I imagine it wouldn’t be any different for a hydraulic shifting system.

bazookasean
bazookasean
8 years ago

Finally, we are getting closer to my dream of hydraulic shifting and electronic brakes!

me
me
8 years ago

bazookasean, wireless brakes…is safer.

lukee
lukee
8 years ago

@slow Joe Crow- The acros system was sold for several years. This year acros stopped selling it due to cost and time it took to make it.

@j- you mean shimano airlines? I still have 2 sets, one was used on a brooklyn tmx. That stuff shifts amazingly. It is the fastest shifting I have ever seen. The huge issue was the number of shifts availible varied depending on temp. It was an exercise in possibilities for shimano. fyi it cost shimano more to make than the $2000 it sold for (it was made in a clean room lab)
@cs- I don’t think that would effect it. I assume it is a sealed system and considering the fluid temp would never rise like it does in brakes, there is no need for expansion so it can be controlled better.

– I like the design, what a fascinating way to do it. I think it has promise, hydraulic lines weigh little and with all the integration in modern bikes once you bleed the system you are problably good for several years. The racheting system ensures a crisp shift but the shift force could be on par with a servo motor.

Dude
Dude
8 years ago

Hydraulic brakes and shifters… replace pads chain and cassette once in a while and otherwise forget about it. If the price is right, could be cool.

Grateful
Grateful
8 years ago

A very complex solution to a very simple problem – which doesn’t exist.

Bill Taylor
Bill Taylor
8 years ago

For all those asking “what does this solve?”.

It solves the issue of Rotor wanting cold hard cash from sales. Not that hard to figure out.

They want a piece of the action, and this is their proposed way to do it. Looks like a pretty good step in the right direction to me, if they can sell it at a good price.

Robius
Robius
8 years ago

Well at least, they are trying to do something new.

Skip
Skip
8 years ago

I had a lot of thoughts about this and a lot of the new stuff, but and I just could not post it so I deleted it and wrote this. I still like the cable/housing system we have now. I like the way it works and I really like to do all the adjusting to make it work just so. Cutting and smoothing the housing getting all of the cables just the right length then tweaking just that last one more time. Then going for a long ride.

greg
greg
8 years ago

Shimano positron shifting had the indexing in the derailleur. Shifter pulled and pushed a thin solid wire through housing.
Acros shifting has the indexing at the derailleur.
You can’t have multiple shifters on hydro unless either one shifter connects to the other shifter, or the system allows the hydraulics to reset every shift. Otherwise at some point you run out of master cylinder travel in one direction.

Matty
Matty
8 years ago

– that’s exactly what happens, the lever returns to its normal position after a shift and sucks the fluid back. Upshift or downshift is determined by how big a fluid slug you pushed (and then sucked back again, which has no effect on the ratchet mechanism).

Clever (as a patent workaround), but I suspect electronic shifting has it licked.

me
me
8 years ago

Love reading all comments and always learning stuff! those Shima Airlines…. didn’t know it exists. Found this auction on ebay for a set for $2500! ….I mean cheaper at $2499.99.
http://www.ebay.com/itm/Vintage-Shimano-Airlines-Rear-DH-Derailleur-System-XTR-M900-SAINT-GT-LOBO-/281325916610?hash=item418054d1c2

Talman
Talman
8 years ago

uhh, isn’t micro shift still doing their thing too?

Dominic
Dominic
8 years ago

I was going to correct you greg on the indexing of the Acros, but i went back and refreshed my memory and you’re right. The coolest thing about it though was that there is a simple little pin with detents marked at different points and it can be swapped out to allow different gear spacings. That shit was genius. The action of the shifter was amazing and the fact that it was always sealed and didn’t need a return spring or batteries makes it the best idea ever, in my book. One day i’ll pick up a set… one day. And that’s where we come to the real reason it’s been discontinued: price

Bazz
Bazz
8 years ago

I wonder when this patent was filed. I’d wager they have a newer patent updating this from hydraulic to electronic.

Joe
Joe
8 years ago

I’m loving this! Place all the complex bits at the end of the line, sealed up nice and tight. No amount of contamination before that point will make a lick of difference to the setup… All it will do is effect lever feel. Plus, the simplicity of those levers is solid!!

Price it low – make it compatible with existing hydro rim and disc brakes – make it light! Sold.

CMZee13
CMZee13
8 years ago

Shimano Airlines!

Tomer
Tomer
8 years ago

I don’t enjoy bleeding my hydraulic brakes on my MTB and the last thing I want is to start bleeding my derailleurs. Just saying.

Crackers
Crackers
8 years ago

I really dig Rotor’s desire to try something new. Crazy new ideas drive real-world innovation.

However, “a single shift lever design… could mean drastically crisper shifts for years without concern for cable stretch, dirt, or gummed up lube or cable housing” and “putting the ratcheting mechanism on the derailleur… would also increase reliability, offering crisper shifts” are both absurd claims based on absolutely nothing. Those statements sound like the biggest bunch of marketing garbage I’ve ever heard. Cables stretch, get dirty, and dry out whether you have one or two of them, and putting a complex ratcheting system closer to the tires inherently increases its risk of contamination.

It’s a given that this site is a marketing machine (and there’s nothing wrong with that), but this article is full of ridiculous claims.

Souleur
Souleur
8 years ago

hmm….lets see, hydraulic fluids…cams, I seemed to have lost a couple sets of SRAM shifters due to routine cleaning and lube and shaving off cams a couple years back

I bet a leaky hydraulic line would not bode any better

and yeah, not sure I’m for priming and then loosing pressure on a ride, o rings and all will surely be flawless….perhaps

I’ll take another $5 cable please

jooo
jooo
8 years ago

There were rumors of this coming from Rotor for years, but I wonder if it will ever make it to market? It seems somewhat pointless when I doubt it can beat electronic systems on performance or cost. Not only that, their design seems so complicated when the 5Rot system had such elegant execution.

It was way out of my price range, but still a shame Acros have discontinued their groupset IMO. From memory there was once talk of them getting a cheaper group to market which used cast/forged pieces, instead of CNC machining everything. I guess they didn’t see a market and didn’t want to pay up-front for the tooling.

Brian
Brian
8 years ago

If this system makes it to market, what we’ll probably see is derailleurs that are sealed to prevent dirt/water intrusion. If the systems it designed properly, it will be easy to bleed and there won’t be any way for air to get into the lines if the bike is inverted (that hasn’t been an issue with hydraulic brakes for a long time now). Hydraulic actuation has the potential to be more reliable and lighter weight than cables or electronics, but it’s all in the design and execution. We’ll just have to wait and see. Personally, I’d love to see it.

Mike C
Mike C
8 years ago

Ooo, I can’t wait to bleed shifting systems along with brakes… (not)

My shifting needs minor adjustment, in the field, far from shop or home workshop:
– Mechanical: I twist some knobs from the saddle and dial it in.
– Electronic: I push some buttons from the saddle and dial it in.
– Hydraulic: I, um, whip out my field bleed kit at the side of the road?!?

wallymann
wallymann
8 years ago

Mike C — bleeding occurs when you first install a hydro system of any sort. like fitting cables, adjusting the pull, bedding the housing, etc. once it’s setup and settled, you’re done with that. with hydro: trim lines, install and fill with fluid, bleed…and you’re done.

after that, you adjust little dials to tweak shifting as needed. just like mechanical, e-shifting, and wireless.

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