HAL9000v2.0
10 kW
Actualy , just few day ago I was reading new patent database and there is about 20 very similar designs. Realy do not see what is the main difference that gave them right to have patent on souch a simple design??
2-speed systems (R-D, dog-clutch or derailleur changing)
- Thread starter Miles
- Start date
HAL9000v2.0
10 kW
There are at least two more. It was in "Patent World magazine" from December or January... I will check...
One is pending from 1990.
One is pending from 1990.
HAL9000v2.0
10 kW
This is interesting 3speed 191% http://mbigear.com/mbi/html/mainproducteng.html
HAL9000v2.0
10 kW
Yesterday I tested some primitive RD system with my HXT and some chains and there is a problem. Setup is made so: motor turns CW lower speed via gearbox, motor turns CCW higher speed via chain. switching is made with two relays that changing 2 fazes of the motor. Controller is this one:
Switching is made by a siemens plc that meassure ressistance of a pot on servo tester, and when it is zero, switch to another direction. Problem is when changing from ccw to cw then motor made click sound, makes few ° in cw directions then go backwards. When the motor is running cw it changes to ccw with no problems. Can't figure out what is the problem but I suspect it is the shity controller ?!?!?
Switching is made by a siemens plc that meassure ressistance of a pot on servo tester, and when it is zero, switch to another direction. Problem is when changing from ccw to cw then motor made click sound, makes few ° in cw directions then go backwards. When the motor is running cw it changes to ccw with no problems. Can't figure out what is the problem but I suspect it is the shity controller ?!?!?
lawsonuw
1 kW
HAL9000v2.0 said:Yesterday I tested some primitive RD system with my HXT and some chains and there is a problem. Setup is made so: motor turns CW lower speed via gearbox, motor turns CCW higher speed via chain. switching is made with two relays that changing 2 fazes of the motor. Controller is this one:
Switching is made by a siemens plc that meassure ressistance of a pot on servo tester, and when it is zero, switch to another direction. Problem is when changing from ccw to cw then motor made click sound, makes few ° in cw directions then go backwards. When the motor is running cw it changes to ccw with no problems. Can't figure out what is the problem but I suspect it is the shity controller ?!?!?
I've got that same controller. Did you get the USB programming dongle? The USB dongle looks like a simple USB to half duplex ttl level rs232 serial adapter. The PC program for setting up the controller allows the direction of the motor to be changed. This has been very reliable for me, though I've never switched directions with the motor still spinning. (switching the phases with a relay should be the same...)
Additionally the PC program has a testing mode that will run the controller from the PC and report motor rpm once the motor's pole number has been entered. If I make a retro-direct transmission I'd strongly consider using this controller and have my supervisory microcontroller always run it in it's PC setup mode.
Lawson
P.S. BINGO (only chip on the dongle) the PC setup program does speak serial.
HAL9000v2.0
10 kW
lawsonuw said:
I use servo tester and codes.
... assembler...
HAL9000v2.0
10 kW
Miles, guess what those are for... 
Storm
100 W
- Joined
- Aug 27, 2007
- Messages
- 108
Sorry if this has been posted already I havn't read this thread. This simple minibike auto centrifical transmission was posted on another forum maybe could be helpful:
$110. from:
http://www.bmikarts.com/shop/?cart=1792769&cat=168&PHPSESSID=b1a5949fbcc31a085d1af17efc38dd93
Fourth one from bottom.
$110. from:
http://www.bmikarts.com/shop/?cart=1792769&cat=168&PHPSESSID=b1a5949fbcc31a085d1af17efc38dd93
Fourth one from bottom.
John in CR
100 TW
Miles,
Thanks for that great visual of how simple a 2 speed tranny can be. I'd want to forget the automatic and get it to a really simple form. A few questions:
1. Would the center shaft that slides to change gears need to be bearing supported? Which do you think would be better, move the entire shaft or slide the pair of gears on the shaft? I'm thinking fix the linear position of the gears on the shaft, but allow the gears to spin (bearings ???), so the shaft doesn't spin, but does slide for easy gear changing linkage.
2. Would we need spur gears with rounded edges like those lego gears, or could simple straight gears do the job?
3. What size gears could we get away with and have reasonable durability with a several Kw motor?
Something like this has group deal written all over it, unless you think a planetary gearbox could be almost as simple and come with a size advantage.
John
Thanks for that great visual of how simple a 2 speed tranny can be. I'd want to forget the automatic and get it to a really simple form. A few questions:
1. Would the center shaft that slides to change gears need to be bearing supported? Which do you think would be better, move the entire shaft or slide the pair of gears on the shaft? I'm thinking fix the linear position of the gears on the shaft, but allow the gears to spin (bearings ???), so the shaft doesn't spin, but does slide for easy gear changing linkage.
2. Would we need spur gears with rounded edges like those lego gears, or could simple straight gears do the job?
3. What size gears could we get away with and have reasonable durability with a several Kw motor?
Something like this has group deal written all over it, unless you think a planetary gearbox could be almost as simple and come with a size advantage.
John
Hi John,
1 You could use roller bearings, or even plain (Oilite) bearings for the axially moving shaft.
2 I think those gears are just a feature of the Lego set - it allows them to be used as straight gears or bevel gears.
3 You just have to do the torque calculations. The HPC catalogue gives recommended values for each size of gear/material etc.
You certainly don't want to go through a double stage to get a 1:1 ratio...........
1 You could use roller bearings, or even plain (Oilite) bearings for the axially moving shaft.
2 I think those gears are just a feature of the Lego set - it allows them to be used as straight gears or bevel gears.
3 You just have to do the torque calculations. The HPC catalogue gives recommended values for each size of gear/material etc.
You certainly don't want to go through a double stage to get a 1:1 ratio...........
John in CR
100 TW
Miles said:
I get that, so we'd want it to replace other reduction(s), but isn't that what I get in 2nd gear with my Nexus 3, or is that 1:1 actually direct?
If we were actually building one, would we want just 2 shafts vs the 3 in the lego tranny, because I'm missing how to accomplish the sliding gear on input or output shaft in the easiest or most durable manner possible.
It seems like for a 2 speed, for reliable and simple we keep getting back to one of your slick Retro-Directs or 2 parallel drives in an over-running pulley/engagement clutch arrangement.
John
12p3phPMDC
1 kW
- Joined
- Mar 16, 2009
- Messages
- 462
Stock Drive product offers splined bushings and shafting to pull of the
sliding aspects.
sliding aspects.
The 3 speed hub gears lock everything together for 1:1 - which you can only do on an epicyclic, of course.
You could do a 2 shaft gearbox, with different reduction ratios (each the same total tooth count). You can use splined shaft. You still need a bearing on the shifting mech., of course.
The gears need to move along the shaft, or the output pulley would have to float....
Then you have to crash the gears or have additional rubber wheels or...........
The retro-direct route looks a lot simpler.......
You could do a 2 shaft gearbox, with different reduction ratios (each the same total tooth count). You can use splined shaft. You still need a bearing on the shifting mech., of course.
The gears need to move along the shaft, or the output pulley would have to float....
Then you have to crash the gears or have additional rubber wheels or...........
The retro-direct route looks a lot simpler.......
John in CR
100 TW
Miles said:
Yeah, sorry I let myself get confused by the lego 2 speed auto. R-D or Evo type, though I seem to want to lean toward belts for sonic reason...don't want to miss the wind noise only of my hubbie too much. I'll see how the 2 Nexus 3's I have hold up first.
BTW, do you have any of the designs you've shared in the build stage yet, or just sharing?
John
