On Wed, 5 Sep 2018 01:06:41 -0700 (PDT), whit3rd <whit3rd@gmail.com> wrote:>Well, not one that fits in the palm of the hand, but automatic >transmissions are not unknown. I've got a couple of 'em >parked outside.We just bought my wife a Nissan Cube. It uses a CVT. The "belt" is a series of roughly trapezoidal stampings from some highly wear-resistant alloy. Just like a snowmobile CVT, the driving pulley changes diameter (under control of the PCM) with RPM. The driven pulley changes diameter proportional to torque requirements. The big difference is that the "belt" is pushed between pulleys instead of being pulled, as with a conventional CVT. In the Cube, this setup is very reliable. We've been looking for the perfect used car for several months. Some had 200,000+ miles on the clock and the CarFax reported no major repairs. John John DeArmond http://www.neon-john.com http://www.tnduction.com Tellico Plains, Occupied TN See website for email address
Very high gain transformerless boost converter - is it possible
Started by ●September 2, 2018
Reply by ●September 5, 20182018-09-05
Reply by ●September 5, 20182018-09-05
On Tuesday, September 4, 2018 at 9:29:48 PM UTC-4, John Larkin wrote:> On Tue, 4 Sep 2018 15:24:35 -0700 (PDT), tabbypurr@gmail.com wrote: > > >On Tuesday, 4 September 2018 22:13:06 UTC+1, John Larkin wrote: > >> On Tue, 4 Sep 2018 13:56:38 -0700 (PDT), jurb6006@gmail.com wrote: > >> > >> >>"I think the record player speed regulator was frictional hence lossy. " > >> > > >> >Yes but against a spring that's wound up that is exactly what is needed. Electric motor not so much... > >> > >> I could imagine a nearly lossless regulator for a wind-up Victrola, > >> but not with 1930's technology. > > > >Were CVs (continuously variable ratio gears) not available then? I assume the reason to not use them was slow controller response loop. > > > > > >NT > > I still feel sorry for mechanical engineers who have no decent > equivalent to a switching regulator.The ratchet and pawl in something like a clock escapement? What do you mean? (There are mechanical analogies to many things.) George H.> > > -- > > John Larkin Highland Technology, Inc trk > > jlarkin att highlandtechnology dott com > http://www.highlandtechnology.com
Reply by ●September 5, 20182018-09-05
On Sep 4, 2018, Tim Williams wrote (in article <pmnj17$rfv$1@dont-email.me>):> <bill.sloman@ieee.org> wrote in message > news:e5382b49-b76b-4e28-a42c-1c6ba8cf00a1@googlegroups.com... > > > I still feel sorry for mechanical engineers who have no decent > > > equivalent to a switching regulator. > > > > It's called a gearbox. Not suitable for gramophone speed regulation, but > > belt drive turntables offer other approaches (not that any of them would > > be a sensible choice in real life). > > That'd be a transformer. > > CVT is the best they've got, but it's a variac, and like a variac, suffers > from losses where the brushes short across turns, and wear.The Honda CR-V has a CVT transmission. I have a CR-V, and it works just fine. I guess I don’t get the point of the WPI effort. Joe Gwinn> > Here's a project that tried: > <https://web.wpi.edu/Pubs/E-project/Available/E-project-042711-231644/unrestric > ted/Switch-Mode_CVT_Torsion_Spring.pdf> > > It's a shame that no material has an extremely high speed of sound. > Beryllium is the highest by far among metals, topped only by diamond > (maybe). That's not very encouraging for an application that's expecting > high impact and abrasion forces... > > I would suspect a hydraulically actuated resonant converter might not be too > terrible, but it would be a pain to design, even worse of a pain to dampen > properly (to keep it from shaking the car apart, let alone be quiet enough > for the passengers), on account of the many more vibrational degrees of > freedom mechanical parts have, compared to electrical circuits; and it still > wouldn't get anywhere near the power density of an electric converter of the > same rating. > > Tim
Reply by ●September 5, 20182018-09-05
"whit3rd" <whit3rd@gmail.com> wrote in message news:1a7e195c-16df-488b-ba6f-5f3df2aa674a@googlegroups.com...> On Tuesday, September 4, 2018 at 6:29:48 PM UTC-7, John Larkin wrote: > >> I still feel sorry for mechanical engineers who have no decent >> equivalent to a switching regulator. > > Well, not one that fits in the palm of the hand, but automatic > transmissions are not unknown. I've got a couple of 'em > parked outside.Those are standard in power distribution as well -- tap changers. :) Tim -- Seven Transistor Labs, LLC Electrical Engineering Consultation and Design Website: https://www.seventransistorlabs.com/
Reply by ●September 5, 20182018-09-05
onsdag den 5. september 2018 kl. 14.20.20 UTC+2 skrev George Herold:> On Tuesday, September 4, 2018 at 9:29:48 PM UTC-4, John Larkin wrote: > > On Tue, 4 Sep 2018 15:24:35 -0700 (PDT), tabbypurr@gmail.com wrote: > > > > >On Tuesday, 4 September 2018 22:13:06 UTC+1, John Larkin wrote: > > >> On Tue, 4 Sep 2018 13:56:38 -0700 (PDT), jurb6006@gmail.com wrote: > > >> > > >> >>"I think the record player speed regulator was frictional hence lossy. " > > >> > > > >> >Yes but against a spring that's wound up that is exactly what is needed. Electric motor not so much... > > >> > > >> I could imagine a nearly lossless regulator for a wind-up Victrola, > > >> but not with 1930's technology. > > > > > >Were CVs (continuously variable ratio gears) not available then? I assume the reason to not use them was slow controller response loop. > > > > > > > > >NT > > > > I still feel sorry for mechanical engineers who have no decent > > equivalent to a switching regulator. > > The ratchet and pawl in something like a clock escapement? > > What do you mean? (There are mechanical analogies to many things.) >I'll assume a (good) infinitely variable gearbox
Reply by ●September 5, 20182018-09-05
On Wed, 05 Sep 2018 08:17:39 -0400, Neon John <no@never.com> wrote:>On Wed, 5 Sep 2018 01:06:41 -0700 (PDT), whit3rd <whit3rd@gmail.com> >wrote: > >>Well, not one that fits in the palm of the hand, but automatic >>transmissions are not unknown. I've got a couple of 'em >>parked outside. > >We just bought my wife a Nissan Cube. It uses a CVT. The "belt" is a >series of roughly trapezoidal stampings from some highly >wear-resistant alloy. Just like a snowmobile CVT, the driving pulley >changes diameter (under control of the PCM) with RPM. The driven >pulley changes diameter proportional to torque requirements. The big >difference is that the "belt" is pushed between pulleys instead of >being pulled, as with a conventional CVT. > >In the Cube, this setup is very reliable. We've been looking for the >perfect used car for several months. Some had 200,000+ miles on the >clock and the CarFax reported no major repairs. > >John > >John DeArmond >http://www.neon-john.com >http://www.tnduction.com >Tellico Plains, Occupied TN >See website for email addressYeah I have a Nissan Rogue with a cvt. Funny but they use software to imitate gear changes. I wouldn't be uncomfortable with the constant change of ratio but their marketing folks disagree I guess.
Reply by ●September 5, 20182018-09-05
"Ingvald44" <noone@nowhere.com> wrote in message news:iq90pdldehggv3sqqlltcr7f89s96s4lfe@4ax.com...> > Yeah I have a Nissan Rogue with a cvt. Funny but they use software to > imitate gear changes. I wouldn't be uncomfortable with the constant > change of ratio but their marketing folks disagree I guess. >Basically everything wrong with mass-market / consumer products is because people are... dumb. Facebook extracts ad revenue by being just annoying enough. Microsoft has annoying features because of many reasons, among them backwards compatibility, point-and-click users, and adding proprietary features to an otherwise standard environment. And cars have sounds and shifting because people want their cars to be bad. :-/ Tim
Reply by ●September 5, 20182018-09-05
onsdag den 5. september 2018 kl. 22.25.54 UTC+2 skrev Tim Williams:> "Ingvald44" <noone@nowhere.com> wrote in message > news:iq90pdldehggv3sqqlltcr7f89s96s4lfe@4ax.com... > > > > Yeah I have a Nissan Rogue with a cvt. Funny but they use software to > > imitate gear changes. I wouldn't be uncomfortable with the constant > > change of ratio but their marketing folks disagree I guess. > > > > Basically everything wrong with mass-market / consumer products is because > people are... dumb. Facebook extracts ad revenue by being just annoying > enough. Microsoft has annoying features because of many reasons, among them > backwards compatibility, point-and-click users, and adding proprietary > features to an otherwise standard environment. And cars have sounds and > shifting because people want their cars to be bad. :-/ >a cvt shifting in steps could possible be a matter of efficiency and wear
Reply by ●September 5, 20182018-09-05
On Tue, 04 Sep 2018 18:29:37 -0700, John Larkin <jjlarkin@highlandtechnology.com> wrote:>On Tue, 4 Sep 2018 15:24:35 -0700 (PDT), tabbypurr@gmail.com wrote: > >>On Tuesday, 4 September 2018 22:13:06 UTC+1, John Larkin wrote: >>> On Tue, 4 Sep 2018 13:56:38 -0700 (PDT), jurb6006@gmail.com wrote: >>> >>> >>"I think the record player speed regulator was frictional hence lossy. " >>> > >>> >Yes but against a spring that's wound up that is exactly what is needed. Electric motor not so much... >>> >>> I could imagine a nearly lossless regulator for a wind-up Victrola, >>> but not with 1930's technology. >> >>Were CVs (continuously variable ratio gears) not available then? I assume the reason to not use them was slow controller response loop. >> >> >>NT > >I still feel sorry for mechanical engineers who have no decent >equivalent to a switching regulator.Clockworks?
Reply by ●September 5, 20182018-09-05
On Wednesday, 5 September 2018 13:15:20 UTC+1, George Herold wrote:> On Tuesday, September 4, 2018 at 10:19:28 PM UTC-4, tabby wrote: > > On Wednesday, 5 September 2018 01:09:41 UTC+1, George Herold wrote: > > > On Tuesday, September 4, 2018 at 6:19:29 PM UTC-4, tabby wrote: > > > > On Tuesday, 4 September 2018 17:35:41 UTC+1, John Larkin wrote: > > > > > On Mon, 3 Sep 2018 21:51:17 -0700 (PDT), whit3rd <whit3rd@gmail.com> > > > > > wrote: > > > > > >On Monday, September 3, 2018 at 1:07:08 AM UTC-7, 69883925...@nospam.org wrote: > > > > > > > > > > > >> And do not forget the 12V DC motor driving a 350V DC generator solution :-) > > > > > > > > > > > >Yes, an electric motor and a rubber band is the basis of many a > > > > > >van de Graaff generator, but it's easier to get 350 kV than it > > > > > >is to get 350W that way. That's REAL high voltage gain. > > > > > > > > > > What's the wall-plug efficiency of a Van de Graaff? > > > > > > > > I'm sure it's zero, +/- not very much. > > > > > > > > > > > > NT > > > > > > Huh, I have no idea, but I'd bet (a beverage) it's better than 1%. > > > > > > George H. > > > I took data at an FEL that used a big ass Van de Graff to > > > accelerate the electrons. > > > > If I were really going to place a bet I'd take you on. I daresay there's a fair difference between the latest higher-tech van de graaf and something from their heyday. > > > Right, (I figure I owe most people here a six pack of 'beverages' > already so another hardly matters.) But I was thinking of a lower > cost 'toy' Van der Graff, like is used in physics demo's. > I could ask some of the physics 'lab guys' to try and measure one. > Heck, someone might have already done it. > > George H. > > > > NTeven a toy one is going to take a couple of watts to run. Output what, a microamp? Maybe we'll see how wrong I am. NT