I had thought that it might be fairly simple to convert the roller
that strikes the bottoms of the keys of an electric typewriter and
sends them flying into the driven roller, and the platen roll moved to
become a passive roller, for a jar mill. The cylindric part I'm
referring to that actuates the keys (maybe it's called an actuator) is
driven thru a pair of belt-and-pulley reductions, and I thought I
could increase the ratio for power instead of speed, and find a
suitable support in the frame for the hard rubber platen roll
(excellent friction) to be the passive roller. I finally got down to
it with an old SCM tonight, until I got it taken apart far enough to
get a good look at that driven roller. It turns out to be polygonal,
not round, in cross section. Looks like it'd be too much trouble to
put a round sleeve around it, so I threw it all away. The case will
still be a good ready box, though, which is what I've been using a
manual typewriter case for.

Robert

Does it look like the roller is hard to remove and put back in?

And only the drive cylinder and jar need good
traction; the passive roller would be fine no matter how much it
slips.

I had thought that it might be fairly simple to convert the roller
that strikes the bottoms of the keys of an electric typewriter and
sends them flying into the driven roller,

and the platen roll moved to
become a passive roller, for a jar mill.  The cylindric part I'm
referring to that actuates the keys (maybe it's called an actuator)

driven thru a pair of belt-and-pulley reductions, and I thought I
could increase the ratio for power instead of speed, and find a
suitable support in the frame for the hard rubber platen roll
(excellent friction) to be the passive roller.

If you're going to mill black powder, place the mill in a
safe location (both for yourself and your neighbors), and power it
through a long extension cord (100 to 250 feet).

A Selectric wouldn't have such a part. I don't know about an IBM
Executive typewriter.

A Selectric definitely does not. It has racks and pinions with detents

You sure? That'd be very different from a clock escape wheel, for
instance.

The type of typewriter I'm referring to has a constantly rotating part
which, when the press of a key-button above sends that part of the key
into it, bats it to cause it to fly against the ribbon & paper. It
substitutes for the lever mechanism of a mechanical typewriter's keys.

Bob <robg... at (no spam) bestweb.net> fired this volley in news:8bab7053-7bd5-4b5e-
8c2f-53b90322a... at (no spam) p36g2000vbn.googlegroups.com:> A Selectric wouldn't have such a part.  I don't know about an IBM
Executive typewriter.

A Selectric definitely does not.  It has racks and pinions with detents
for position selection to move the ball.



You sure?  That'd be very different from a clock escape wheel, for
instance.

The type of typewriter I'm referring to has a constantly rotating part
which, when the press of a key-button above sends that part of the key
into it, bats it to cause it to fly against the ribbon & paper.  It
substitutes for the lever mechanism of a mechanical typewriter's keys.

It definitely is NOT an escapment in any mechanical jargon.  It might be
that IBM or other typewriter manufacturers may have given it that
moniker, but it certainly is not one. "Impeller" would be more
appropriate.  In most incarnations in which I've seen it, a rubber-coated
roller spins continuously, and the individual key arms are lifted by the
keyboard stroke against the roller.  A "shoe" on the bottom of each arm
is tractioned by the roller so as to accelerate the arm to the platen.  
The shoe teeters out of the way on the retract stroke so that the key arm
is allowed to fall back to the home position without re-engaging the
"impeller" roller.  The keyboard key has a pawl that won't re-engage the
key arm until it's released, so the key won't strike multiple times when
pressed.  Some keys lack the pawl (like the space bar), and will multi-
strike if held down.

"Escapement", it's not.  I won't vouch for what Royal or others called
it, though.

LLoyd

It definitely is NOT an escapement in any mechanical jargon.  It might be
that IBM or other typewriter manufacturers may have given it that
moniker, but it certainly is not one. "Impeller" would be more
appropriate.  In most incarnations in which I've seen it, a rubber-coated
roller spins continuously,

 The driving roller in an IBM "Executive" typewriter is called the "Power
Roll". The process of pressing a key on that type machine did a couple of
things. First, as elsewhere described, it tripped the catch on the key cam
mechanism which let the cam shoe contact the power roll and power the
keystroke and it also triggered the escapement mechanism which allowed the
carriage to advance one position after the keystroke so as to be ready for
the next key to strike. The escapement mechanism in the "Executive" was an
extension of the classic "Marine Escapement" in spring clocks except that
instead of a toothwheel that the pawls on either end of the escapement lever
contacted the teeth were machined into a rack at the rear of the carriage..

Bob <robg... at (no spam) bestweb.net> fired this volley in news:8bab7053-7bd5-4b5e-
8c2f-53b90322a... at (no spam) p36g2000vbn.googlegroups.com:> A Selectric wouldn't have
such a part. I don't know about an IBM
Executive typewriter.

A Selectric definitely does not. It has racks and pinions with detents
for position selection to move the ball.



You sure? That'd be very different from a clock escape wheel, for
instance.

The type of typewriter I'm referring to has a constantly rotating part
which, when the press of a key-button above sends that part of the key
into it, bats it to cause it to fly against the ribbon & paper. It
substitutes for the lever mechanism of a mechanical typewriter's keys.

It definitely is NOT an escapment in any mechanical jargon. It might be
that IBM or other typewriter manufacturers may have given it that
moniker, but it certainly is not one. "Impeller" would be more
appropriate. In most incarnations in which I've seen it, a rubber-coated
roller spins continuously, and the individual key arms are lifted by the
keyboard stroke against the roller. A "shoe" on the bottom of each arm
is tractioned by the roller so as to accelerate the arm to the platen.
The shoe teeters out of the way on the retract stroke so that the key arm
is allowed to fall back to the home position without re-engaging the
"impeller" roller. The keyboard key has a pawl that won't re-engage the
key arm until it's released, so the key won't strike multiple times when
pressed. Some keys lack the pawl (like the space bar), and will multi-
strike if held down.

"Escapement", it's not. I won't vouch for what Royal or others called
it, though.

LLoyd

Similarly I thought the darkness setting on a toaster worked via a
timing cam, because, again, that's what seemed straightforward, and
the outward appearance of the device was consistent with that
impression.