pic: Helical Gears?


That is a helical gear…right?

from what i can see, yes it is.

edit: after reading the thread related to this picture, it looks like an optical illusion. weird.

Haha, I know that transmission anywhere (after spending hours with my face about two inches away from it. I hope all that drool didn’t make the gears bind up too bad :D). That is West Covina High School team 968’s 2006 transmission. That is a 32 pitch standard spur gear. No helical gears anywhere on that bot. Must just be something funky going on with the picture.

What he said^^^^

This picture is disturbing. How does it look like perfect continuous diagonal lines on both the pinion gear and the driven gear, and normal spur elsewhere? My best guess is that these are normal spurs with a little groove in the middle of each tooth… I have seen that before but I still can’t see it looking like perfect diagonals in the picture.

If you look closely, you can also see that if we did assume they are helical gears, then the helix angles of the two gears would not mesh! One of the gears would need the angles reversed from what is shown.

It’s an image artifact. The spacing of the gear teeth in the image is close to the size of the pixels, and the JPEG compression picks up on the diagonal aliasing and enhances it. Look at the bright area on the left end of the CIM motor and you’ll see the same kind of illusion.

If you want a better picture, go to the thread above, Gear Types. My mentor Travis Covington posted a clearer picture of the gears for all to see.

it looks like the photo is a small part of a larger picture, and this section was enlarged with photoshop or some other editing program.

When you scale an image up the program has to make assumptions about what is between pixels. Sometimes you get aliasing, and patterns are created where there was no pattern in the original photo (in this case, diagonal lines).

Here is the other thread that has the pictures in it and further discussion as well.