Hey all, long time no post. Just noticed this D drive and I just happen to have started on a triple diff transmission using planetary gears for my big tank There are so many similarities with the D drive and a modern triple diff tank transmission. What this guy has done is modify the steering diff to become a drive diff. The smaller motor to change the ratio is the motor that would steer the tank and give it reverse. It works exactly the same.
When I saw this I understood it because I have been toying for a few months and have already started buying the gears etc. The difference is in the D drive the main motor is permanently running at optimum speed and the smaller motor changes the gear ratio to the point of also giving it reverse. In a tank the main motor has a variable speed and the steering has also so when combined you can mix between the two to get speed and steering. Still early days for pics but if there is any interest in this project I will put some up. I have built many vehicles and its become clear that a 3 diff setup is what I have been looking for, its a beautiful thing but not required for paint ball at all, having said that I do expect to have a lot more control at high speeds compared to a skid steer tank, will be interesting. George On 17/5/10 2:13 AM, "Clark Ward Jr" <[email protected]> wrote: > Thanks Bill, your drill-press example cleared it up for me quite a bit :) > > On Sun, May 16, 2010 at 11:38 AM, Bill Hamilton <[email protected]> wrote: >> A cone-and-belt cvt works like the pulley stacks in a drill press drive. >> Only, instead of two sets of pulleys, you have two cones and a mechanism to >> keep the belt taut on those cones. Move the belt one way and you get more >> torque, less speed. Move it the other, you get more speed, less torque. >> >> -Bill Hamilton >> >> On May 16, 2010, at 9:34 AM, Clark Ward Jr <[email protected]> wrote: >> >>> Thanks, my Bosch blue book doesn't have a lot of detail on how exactly >>> a CVT works, only something about a band that moves between two >>> cones.... I will find a book that explains it someday. But I agree, >>> anytime someone claims an 'order of magnitude' efficiency improvement, >>> it's time to be skeptical. >>> >>> On Sun, May 16, 2010 at 7:40 AM, Ben Holko <[email protected]> wrote: >>>> >>>> A CVT should not slip, if it does it has too much torque put through it. >>>> A 'la it WILL slip if you put more torque through than it can handle. >>>> Having >>>> said that, there is friction there which is what is stopping it from >>>> slipping, while this geared approach has (basically) no friction. Think of >>>> it like the gears of a manual gearbox, with the variability of a CVT. >>>> >>>> Ben >>>> >>>> >>>> -----Original Message----- >>>> From: [email protected] >>>> [mailto:[email protected]] On Behalf Of Clark Ward Jr >>>> Sent: Sunday, 16 May 2010 9:26 PM >>>> To: [email protected] >>>> Subject: Re: [TANKS] Absolute genius >>>> >>>> Aren't CVTs less efficient than geared transmissions, given that they are >>>> slipping the whole time? Or do I misunderstand the technology vis-a-vis >>>> the >>>> slipping belt and the cones of a CVT? >>>> >>>> On Sat, May 15, 2010 at 10:26 PM, Don Shankin <[email protected]> wrote: >>>>> >>>>> >>>>> On Sat, May 15, 2010 at 7:19 PM, Ben Holko <[email protected]> wrote: >>>>>> >>>>>> http://www.youtube.com/watch?v=F6zE__J0YIU >>>>>> >>>>>> >>>>>> >>>>>> This thing may revolutionize all transmissions. >>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> You are currently subscribed to the "R/C Tank Combat" group. >>>>>> To post a message, send email to [email protected] To >>>>>> unsubscribe, send email to [email protected] >>>>>> Visit the group at http://groups.google.com/group/rctankcombat >>>>> >>>>> >>>>> Nice concept. I'm glad they addressed my concern of having to power >>>>> the second shaft. I was on board until he said he estimated it to be >>>>> an _order of magnitude_ more efficient than the current CVT >>>>> transmissions (not geared transmissions, but CVTs even!). We'll see >>>>> where this ends up when you figure in powering that second shaft. I'm >>>>> guessing (with no facts or numbers whatsoever) that it will be on par >>>>> with losses associated with a torque converter (which may be OK >>>>> because at the end of the day this thing is still a high-torque CVT). >>>>> >>>>> -Don "I'm a computer engineer not a mechanical engineer" Shankin >>>>> >>>>> -- >>>>> You are currently subscribed to the "R/C Tank Combat" group. >>>>> To post a message, send email to [email protected] To >>>>> unsubscribe, send email to [email protected] >>>>> Visit the group at http://groups.google.com/group/rctankcombat >>>> >>>> >>>> >>>> -- >>>> Clark in Georgia >>>> >>>> -- >>>> You are currently subscribed to the "R/C Tank Combat" group. >>>> To post a message, send email to [email protected] To >>>> unsubscribe, send email to [email protected] >>>> Visit the group at http://groups.google.com/group/rctankcombat >>>> >>>> -- >>>> You are currently subscribed to the "R/C Tank Combat" group. >>>> To post a message, send email to [email protected] >>>> To unsubscribe, send email to [email protected] >>>> Visit the group at http://groups.google.com/group/rctankcombat >>> >>> >>> >>> -- >>> Clark in Georgia >>> >>> -- >>> You are currently subscribed to the "R/C Tank Combat" group. >>> To post a message, send email to [email protected] >>> To unsubscribe, send email to [email protected] >>> Visit the group at http://groups.google.com/group/rctankcombat >> >> -- >> You are currently subscribed to the "R/C Tank Combat" group. >> To post a message, send email to [email protected] >> To unsubscribe, send email to [email protected] >> Visit the group at http://groups.google.com/group/rctankcombat > > -- You are currently subscribed to the "R/C Tank Combat" group. To post a message, send email to [email protected] To unsubscribe, send email to [email protected] Visit the group at http://groups.google.com/group/rctankcombat
