N.U.C. and the uni prototypes

Greetings all

I do not know when the best time for the display of the prototypes will
be. I am leaning toward the 17th and 18th. This seems to be the time when
the auditorium is in use. I do not have a place to display them and not
knowing the layout of the facility I am flying blind. Donna and I can only
stay a couple of days so this is also a limiting factor.

I will send a letter to the event organizers to see what they think.
Anyone have any suggestions as to the best times. Or even a place to put
them. Sorry for such short notice folks.

A couple of fellows asked for more info on the uni’s design and what not,
I will try to round up a web sight for some pictures. It almost seems like
I am begging here but, anyone want to host the pictures of the
transmission and electric uni.

Now to the meat of the matter. The electric uni is not what you would
think. First you stand on the rascal. The “pedals” are 5 inches off of the
ground. She has a 12 inch tire with a clutch activated motor driving the
perimeter of the tire. Basically you hold the brake to mount the
“unistick” once balanced you release the brake at the same time squeeze
the clutch. This forces the motor spindle onto the tire. The clutch works
in the dead man configuration. Hence depressing the clutch engages the
tire and turns on the motor. If released the motor shuts off and
disengages the perimeter of the tire. An aluminum tube attached to the
forks holds the batteries. Currently 12 “c” cells. Straight handle bars,
with no speed control are attached at the top of the 3 1/2 foot tube. She
stands a total of 4ft 5 in Heck she only goes 2 miles an hour. Once I get
the hang of it I will install a weed eater engine!!

Now the variable speed uni is the real kicker. The simplest of the designs
turned out to be the best of all the experiments. The answer was under my
seat so to speak. Every week I mow the grass with a lawn tractor. There
was the answer. More on that later.

First any uni transmission must not slip when changing speeds. So gears
and derailleur are out of the question. This leaves belt drives. The
system is simply three pulleys. Two are off the shelve sheaves, 5 inches
in diameter. The third I build, it is the heart of the system. Think of a
spool of thread, just the spool. Now put a floating pulley on the shaft of
the spool. The floating pulley is of such a design that when pressed
against either side of the spool it will form a complete sheave. Install
two belts onto the" thread spool". One going to the driven 5 in. pulley
the other belt going to the driver 5 in. pulley.

Now you have three pulleys lined up with each other the center pulley is
the “thread spool”. Now the center pulley is movable. It can travel either
closer to the driven pulley, thus further from the driver. Or vice versa.
Since the belts will not stretch the center pulley must compensate. The
movement of the center pulley is best described as pinching. One belt will
pinch the floating center section toward the opposite end of the spool.
There by increasing the diameter of that end and at the same time
decreasing its diameter. Now you have an idler between the driven pulley
and driver who’s ratio is variable.

The same design used on variable speed lawn tractors, industrial band saws
etc… This is a very simplified explanation of the system. If you want
more details I will be glad to share all the technical drawing, angles of
pulleys, bearing loading etc at the show.

Joe

There seems to be great interest in uni prototypes. Would anyone like to
lead a “Show and Tell” workshop at the NUC, where anyone that has a new
fangled machine can come and display? We could put out a public call for
new uni designs.

At the very least the Toronto Unicyclists will provide a space for anyone
with new technology. If you’re interested please e-mail
TorontoUnicyclists@Canada.com

Don Tai http://torontounicyclists.tripod.com Don_TaiATyahooDOTcoDOTuk

Joe West wrote:

> Greetings all
>
> I do not know when the best time for the display of the prototypes will
> be. I am leaning toward the 17th and 18th. This seems to be the time
> when the auditorium is in use. I do not have a place to display them and
> not knowing the layout of the facility I am flying blind. Donna and I
> can only stay a couple of days so this is also a limiting factor.
>
> I will send a letter to the event organizers to see what they think.
> Anyone have any suggestions as to the best times. Or even a place to put
> them. Sorry for such short notice folks.
>
> A couple of fellows asked for more info on the uni’s design and what
> not, I will try to round up a web sight for some pictures. It almost
> seems like I am begging here but, anyone want to host the pictures of
> the transmission and electric uni.
>
> Now to the meat of the matter. The electric uni is not what you would
> think. First you stand on the rascal. The “pedals” are 5 inches off of
> the ground. She has a 12 inch tire with a clutch activated motor driving
> the perimeter of the tire. Basically you hold the brake to mount the
> “unistick” once balanced you release the brake at the same time squeeze
> the clutch. This forces the motor spindle onto the tire. The clutch
> works in the dead man configuration. Hence depressing the clutch engages
> the tire and turns on the motor. If released the motor shuts off and
> disengages the perimeter of the tire. An aluminum tube attached to the
> forks holds the batteries. Currently 12 “c” cells. Straight handle bars,
> with no speed control are attached at the top of the 3 1/2 foot tube.
> She stands a total of 4ft 5 in Heck she only goes 2 miles an hour. Once
> I get the hang of it I will install a weed eater engine!!
>
> Now the variable speed uni is the real kicker. The simplest of the
> designs turned out to be the best of all the experiments. The answer was
> under my seat so to speak. Every week I mow the grass with a lawn
> tractor. There was the answer. More on that later.
>
> First any uni transmission must not slip when changing speeds. So gears
> and derailleur are out of the question. This leaves belt drives. The
> system is simply three pulleys. Two are off the shelve sheaves, 5 inches
> in diameter. The third I build, it is the heart of the system. Think of
> a spool of thread, just the spool. Now put a floating pulley on the
> shaft of the spool. The floating pulley is of such a design that when
> pressed against either side of the spool it will form a complete sheave.
> Install two belts onto the" thread spool". One going to the driven 5 in.
> pulley the other belt going to the driver 5 in. pulley.
>
> Now you have three pulleys lined up with each other the center pulley is
> the “thread spool”. Now the center pulley is movable. It can travel
> either closer to the driven pulley, thus further from the driver. Or
> vice versa. Since the belts will not stretch the center pulley must
> compensate. The movement of the center pulley is best described as
> pinching. One belt will pinch the floating center section toward the
> opposite end of the spool. There by increasing the diameter of that end
> and at the same time decreasing its diameter. Now you have an idler
> between the driven pulley and driver who’s ratio is variable.
>
> The same design used on variable speed lawn tractors, industrial band
> saws etc… This is a very simplified explanation of the system. If
> you want more details I will be glad to share all the technical drawing,
> angles of pulleys, bearing loading etc at the show.
>
> Joe