pic: 571's new gearz loose weight

[CD47-Bot]

loading photo ...

[jacob_dilles]

wow awsome gear box. how does it shift?

[Arefin Bari]

question?.... how much does that gearbox weight? it looks nice...

[OneAngryDaisy]

the picture says 12 pounds. thats one heavy sucker, 24 combined

[Jones571]

when they are in the bot they have a tiny air cylinder that shifts them i think it is like a 3/4'' by 1 inch stroke

each gear box weighs close enough to call them 6 pounds each in round numbers. they are awesome and designed that no matter what side of the bot they are on that they run forward to get the best performance possible a nice added bonus. Ill look for a pick on how they shift and post it tonight

[Austin]

Correct me if I'm wrong, but this looks very similar to the Technokats' 2002-2004 shifting technique. If it is...
This is a shift-on-the-fly system that uses two free-spinning gears (The outer two on the right of this pic) with some sort of mechanism that will engage with that center "dog" (between the two outer gears on the right). This center dog is connected to the shaft so that the shaft cannot spin w/out the dog spinning, and vise-versa. Hi/Lo gear is determined by which gear the dog is engaged in. I hope that this answers your question.

check this out for drawings of and other info on our 2003 gearbox --> http://technokats.org/archive.htm

[Jones571]

i tryed to upload a picture with the shifter in there but is said it was to big. if you want me to send a pic of it to u i will be glad just email me JcSpyder1211@aol.com and ill send it out to u

[Solace]

just for clarification...

yes, it does use the same principles as the Technocat transmission, but follows the design only very loosely.

the two of the gears on the output shaft have had dogs machined into, creating a standard 7/8" (i think) hex head. the engaging mechanism is a relative cheap 7/8" socket wrench attachment, which can slide in between connecting the low gear or the high gear. the shifting is done using a 3/4" ram which shifts both sides at the same time.

Each gear box weighs 6 pounds. The wheel output shaft is connected to a single chain that connects all wheels on a side. On one of the gearboxes, the alternative output shaft runs into another dog engaging mechanism identical to the one that switches the gears itself. activating the piston on that shifter hooks the output of the gearbox to the winch.

I do have pictures of the shifter, i will attach them as soon as i get back on my own computer.

[Arefin Bari]

Originally Posted by OneAngryDaisy

the picture says 12 pounds. thats one heavy sucker, 24 combined

i dont blame them... our each transmission weights 15 pounds...

[RogerR]

Originally Posted by mechman108

i dont blame them... our each transmission weights 15 pounds...

hah! ours weigh almost double that!.....but then again, ours run the length of the bot...

http://www.chiefdelphi.com/forums/pictures.php?s=&action=single&picid=6516&direction =DESC&sort=date&perrow=4&trows=3&quiet=Verbose

I never really appreciated speed holes until after building that bot

[Jones571]

but that is 12 pounds for both of the trani'z not each

y do your trani'z run the length of your bot?

[RogerR]

Originally Posted by Jones571

y do your trani'z run the length of your bot?

we're using direct-drive (spur gears) instead of chain or pulleys to transfer power from the motors to the wheels of our bot

[Jones571]

y do that the weight must be a killer. It really eats up your weight limit quickly? im not seeing the benefit of that.

[RogerR]

Originally Posted by Jones571

y do that the weight must be a killer. It really eats up your weight limit quickly? im not seeing the benefit of that.

actually, in the begining, we weighed about 78 lbs, but after some lightening holes in the gears, turning down the hubs, and replacting many steel parts with aluminum, we dropped almost 15 pounds. we didn't want to deal with the loss of effciency and other problems that chain drives can have if they aren't designed properly. we actually modeled our drivetrain after team 25, so we aren't the only ones to do this.

[Jones571]

yea i can understand that 25 had an sweet drive train last year i cant watie to see what they did this year.