Bicycle Mechanics - What is this dangley thing from the Hub??

Hey again guys and gals,

http://patentpending.blogs.com/photos/uncategorized/surmey_archer_1.gif

The picture above resembles a hub, was wondering what that danglely thing is that hangs out the right-hand end - what is it there for?

Also why are there gears in the hub? Dont the shift gears change the torque/speed for the bike? Or is this not entirely true?

Thanks,

Aaron.

Link to Website: http://patentpending.blogs.com/patent_pending_blog/bicycle_technology/

The chain connects to a cable that is attached to a shifter on the handlebars.
The gears are shifted manually.

Enjoy

Thanks for fast reply...

How does the danglely thing (chain) that is attached to a cable connected to the handbars interchange the gears in the hub to select between the 3-speeds? From the diagram shown in the previous post, does it pull the middle gear through or what? Cannot see from schematic how it will engage between the 3 speeds.

:eek: Thanks

The chain is connected to a pin that slides inside the hub.
Movements in the pin position change the position of the spring loaded piece shown in the diagram.

I believe Sheldon Brown has several exploded diagrams on his website.

Enjoy

is this, like, a joke...?

lol, nah i just dont know squat about bikes and i have to redesign the hub of a bicycle as a project.

lol, nah i just dont know squat about bikes and i have to redesign the hub of a bicycle as a project.
This is not a "standard" hub on modern lightweight bicycles. It is a 3-speed hub, meaning that the hub is INTERNALLY geared. The means of changing gears is complex, and bears some resemblence to a car transmission. Most modern bikes (though not all) have external/derailer gears meaning that the gearing is outside the hub and is shifted by moving a chain between different sprockets.

Here's a ton of info on 3-speed Sturmey Archer hubs and how they work: http://www.sheldonbrown.com/sturmey-archer.html#how

If you're re-designing an internally geared hub, try and make it lighter. You manage to do that, your project could turn into a nice business:D.

Thanks guys

If you're re-designing an internally geared hub, try and make it lighter. You manage to do that, your project could turn into a nice business:D.

Also, how about bringing the 3 speed fixed gear hub back into production? And make it so that it can freewheel at the flick of a lever! And make it weigh 400 grams. And look cool.

I'd buy that :)

Unless you were assigned this type of hub, you might want to investigate the design of a typical bicycle hub. This is far simpler than the hub you presented. Try starting with www.shimano.com and look for a front or rear hub service document with an exploded view.

Thanks again guys, moxfyre...ill send you an invoice when done ;)

Anyways, i really need the CAD files for the old 3-speed design

Anyone know where i can get them?

See
http://www.users.globalnet.co.uk/~hadland/samaintind.htm

SRAM, Shimano and Rohloff also make internal hub gears using slightly different designs.
When you say "redesign", what do you mean? The current design works. If you change the design for no good reason, it probably won't work. Do you want to make it lighter, more efficient, more gears, better looking, cheaper, more expensive, more reliable ?

There are some comments on the AW model design at
http://draco.acs.uci.edu/rbfaq/FAQ/8f.18.html
and the SW model at
http://my.ohio.voyager.net/~bdhayes/sa/sw.htm

I have a similar hub on a 1972? Univega Tri-Star 3spd mixte:

http://www.geocities.com/edinger03/images/03_Univega_hub.jpg

Hey,

When i say redesign, i have a project which revolves around Modular Production Systems - basically process to manufacture components efficiently. I need to change the current manufacturing techniques (i.e. CNC lathe machining for the Hub shell) to try and be more efficient. So in areas where there are many washers of different sizes...try and make the majority the same size as this would be more cost effective.

So i basically just need a CAD file of a "already designed" bicycles Hub arrangement (preferrably exploded) but if not, anything will do! From this i will change the rest as im not an expert on the understanding of the functioning of the hub. Other than it uses a planetary gearing system to change between the gearing speeds. I have no knowledge of dimensioning & components (some of them i cannot see from the pics provided by websites).

So yeah, i was hoping that you guys would know of a site with all these technical aspects i can download from???

Thanks again

:crash: Very Frustrating

<snip> So yeah, i was hoping that you guys would know of a site with all these technical aspects i can download from???

Have you tried searching the US trademark and patent database?

Here is a link to the search page: http://www.uspto.gov/patft/index.html

Here is a patent application for a planetary gear shifting hub (http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&u=/netahtml/search-adv.htm&r=37&f=G&l=50&d=PTXT&p=1&p=1&S1=((bicycle+AND+geared)+AND+hub)&OS=bicycle+AND+geared+AND+hub&RS=((bicycle+AND+geared)+AND+hub))

There are no "CAD" files for bike products manufactured pre-1980.
You simply buy one, disassemble it and create your own drawings.
That's what I did when I had undergrad engineering projects.

Enjoy

Ah spew hey.


Cheers for all your help guys!

Hey,

When i say redesign, i have a project which revolves around Modular Production Systems - basically process to manufacture components efficiently. I need to change the current manufacturing techniques (i.e. CNC lathe machining for the Hub shell) to try and be more efficient. So in areas where there are many washers of different sizes...try and make the majority the same size as this would be more cost effective.

So i basically just need a CAD file of a "already designed" bicycles Hub arrangement (preferrably exploded) but if not, anything will do! From this i will change the rest as im not an expert on the understanding of the functioning of the hub. Other than it uses a planetary gearing system to change between the gearing speeds. I have no knowledge of dimensioning & components (some of them i cannot see from the pics provided by websites).

So yeah, i was hoping that you guys would know of a site with all these technical aspects i can download from???

Thanks again

:crash: Very Frustrating

I doubt that the companies release detailed technical drawings, but just go to their websites and check! There are certainly bike mechanics out there who have learned how they work in great detail (such as Sheldon Brown), but I doubt you're going to find a complete set of mechanical drawings for one.

In order to improve the manufacturing efficiencies, you'll need to knowing a lot about how internally geared hubs work and about how the rest of the bike works as well. There are a variety of constraints on IG hub design: wear, weight, ability to shift easily, ability to withstand a large amount of torque on the driving sprocket, fitting in a small cylindrical space. I think that the space and weight constraints in particular probably make it very difficult to optimize the sizes of the various components.

Do what powers2b suggested, find one and take it apart.

Also when it comes to the many different washer sizes, consider that that the hub is full of oil and the washers keep oil inside and dirt outside. Rohloff recently redesigned their washer system to ensure this happens with their hub.

OK, now I understand your project. It's hard to keep up when you start three separate threads for the same thing.

If you want a CAD file for a geared hub, you will need to contact the manufacturer and see if they will send you one. However, unless you are offering them something in return - like rights to use your design - you are unlikely to get any cooperation from them. But that's for them to determine.

I have a similar hub on a 1972? Univega Tri-Star 3spd mixte:

http://www.geocities.com/edinger03/images/03_Univega_hub.jpg
With a chain that's begging for oil by the looks of it

Ok so email manufacturers for the CAD files saying that i will be referencing all diagrams as for a project. Do you know of any good manufacturing sites for bicycle hubs?

That's the hub in my older brother's 3-speed Stingray that got passed down to me, I got to figure lots of stuff on that puppy out starting at about age 10..... :-)

I think the only cost reduction change in the Sturmey archer 3 sp hub happened in about 1907, when they quit using ball bearings for the little pinion wheels, in favour of plain bushings.

With a chain that's begging for oil by the looks of it

LOL - I found the bike at the dump - that chain is long gone...

*********

Here's a diagram I found of a Rohlhoff Speed Hub:

http://www.jimlangley.net/ride/whrohlofflg.jpg

jeeezzz, nice and simple design ;)

I'll bet those things were designed and were obsolete before CAD systems ever came along. I doubt that there was ever a CAD drawing done on them.

possibly subassemblies but i think more likely to be in Inventor or Solidworks to see the assembly process also.