Exercise equipment is not necessary and not particularly helpful. First off, when you are stretching, please do *not* bounce. It risks tearing muscle fibers instead of stretching them.
Instead, consider what you are stretching. To do a full split, you need flexibility in your hamstrings (the back of your thigh) and your hip flexors (the front of your hip/thigh). Stretch your hamstrings by lying on your back and using a belt or a sheet around your foot with your leg out straight. You can also lie down at a doorway, one leg through the door, the other leg propped up on the wall. Use your muscles to push your leg into the wall for a count of 5, then relax and let your leg straighten more or scoot your butt closer to the wall to feel more of a stretch in the back of your leg. Repeat 3 times, twice a day.
You can try to stretch the front of your hip by doing a “pigeon” stretch. http://www.fitsugar.com/121200 Be sure you keep your stomach tight to stretch your hips, *not* your back.
Good luck and remember to warm up before you stretch.

Yes, there’s a specific machine that you sit in, and it spreads your legs out into the side splits. You can control the degree of how wide it spreads your legs. It helped me get into the full side splits.

you just need to practice it every day.. about 30 counts of bouncing twice might do.. i used to do that every day and now i can do a full split.. no machines..

Do yoga exercises, it increases your flexibiility by alot.