0
$\begingroup$

okay so I’m trying to build a tennis ball launcher for my school so we can showcase it- my teacher helped me get motors and stuff setup similar to this image.

Question: How would I include a spring so that (after we manually compress it) anyone can use a button or something to release the spring and push the ball towards the wheels please? I can’t find anything simple? ![enter image description here]![enter image description here]enter image description here

I was thinking of having a bung or something at the end of the spring??

$\endgroup$
0

2 Answers 2

1
$\begingroup$

Another idea just for the sake of fun.

enter image description here

Suggested locking mechanism.

enter image description here

Crossectional View

enter image description here

$\endgroup$
8
  • $\begingroup$ How do we control the piston please for it to release? Can I remote sort of control it? $\endgroup$
    – Edwin
    Nov 23, 2021 at 17:09
  • $\begingroup$ You need to manually load the ball and slide the front plate against the piston or spring to set the ball into ready to shot position, then release the handle to propel the ball. You can make a vertical notch near the end of the slot to lock the handle if desired. $\endgroup$
    – r13
    Nov 23, 2021 at 17:14
  • $\begingroup$ Is there a way to use a motor to release it from the notch please then the motor turns off after that? $\endgroup$
    – Edwin
    Nov 24, 2021 at 9:08
  • $\begingroup$ I think it can but requires adding much more details. The simple idea is to attach something to the handlers after it has been set in the ready position, then start the motor to lift the handler to the shoot position. However, the trick is this lock needs to be either released upon impact or follow the motion of the handlers. I'll leave it to you to think about. $\endgroup$
    – r13
    Nov 24, 2021 at 15:32
  • $\begingroup$ Hi, what’s a handler please? My teacher said that the piston idea is in budget if we use a Bung instead as we have lots of those in Science department downstairs $\endgroup$
    – Edwin
    Nov 24, 2021 at 19:27
2
$\begingroup$

Why do you need a spring?

Have a vertical tube with a gentle curve to feed the balls and all you need is a small pin to stop the balls getting to the drive mechanism. The mass of the balls will autofeed...

Or you can make a "gate" to allow one at a time... Perhaps think of a pinball machine.

So, how about two pins which need to be linked together. As one moves out to allow the ball to get to the drive wheels, the other moves in to prevent "full auto"...

enter image description here

$\endgroup$
14
  • $\begingroup$ Hi, my teacher said for safety (so we can stand away) and so that people can press it and watch the ball shoot off, so to make it interactive and more fun? Some kids may use it too I think $\endgroup$
    – Edwin
    Nov 23, 2021 at 15:54
  • $\begingroup$ Yeah, I just need a way to make the spring release button controlled? The pinball one we would hold I think and release manually? $\endgroup$
    – Edwin
    Nov 23, 2021 at 15:57
  • $\begingroup$ Will you use your rapid fire ability device for good? Or for evil? A simple mechanical button will require you to be up close so that fails if safety is your concern. Propose the gravity feed tube to your teacher. It is also safer in the sense you don't need to be at the business end to load. No accidental ball in the face if you load it while it is on. $\endgroup$
    – DKNguyen
    Nov 23, 2021 at 16:15
  • $\begingroup$ Hi, Sir said that he wanted like a controller with just one switch sort of thing to release the spring, he said we have wire to make it like at least 3m long $\endgroup$
    – Edwin
    Nov 23, 2021 at 16:16
  • 1
    $\begingroup$ @Edwin That's unfortunate. I have no idea why your teacher wants a muzzle loader when people have been trying to get away from muzzle loaders to breechloaders for centuries. The advantage of a muzzleloaders is that it was simpler but in this case it is more complicated. $\endgroup$
    – DKNguyen
    Nov 23, 2021 at 20:08

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.