Electric ball valve?

[Hunt_and_Annoy]

Has anyone ever tried hooking a ball valve up to a high torque motor for faster opening?

[aEx155]

A high torque motor would be VERY slow in order to have enough torque to turn a ball valve. Otherwise, the motor would have to be bigger, heavier, and more expensive in order to turn it faster than a person with a torque are could. It's not feasible. Sorry.

http://www.robotroom.com/PCB-Cutter-...zed-Shear.html

Originally Posted by From above site

...with 2178:1 ratio gearmotor (P42 14 0 2178). The output shaft rotates at approximately 4 RPM @ 24V.

Just to provide an example of a high torque motor and it's use. I know it isn't a good comparison, but it shows a good example of a high torque motor and what it can't do...

[Hunt_and_Annoy]

What if you hooked it up to some gearing?

Another idea: Use an electromagnet to open and close a ball valve. Trouble is both of these need quite a bit of power and/or weight.

[aEx155]

Like you said, the problem is power. It really isn't worth the effort to hook up something electrical to a ball valve, unless you were trying to make some kind of remote-firing device. If you aren't, the it really is easier to just add a torque arm.

I've had experience with motors and robots and such, and, even with gearing, it takes a lot of force. The motor alone woul be as large or larger than the ball vale itself, making it very bulky.

[Ben]

It's possible, but as aEx155 said, you would need a motor that's pretty hefty. I've messed around with high torque motors before and I don't think they're right for water guns due to their weight/size and the fact that they use electricity.

Some sort of pulley based ball valve system would be more ideal in my opinion. I haven't made one yet but I've experimented with it and it seems perfectly possible.

[aEx155]

Originally Posted by Ben

Some sort of pulley based ball valve system would be more ideal in my opinion. I haven't made one yet but I've experimented with it and it seems perfectly possible.

What were you thinking of, Ben? Would it be a way to relocate the trigger?

[Hunt_and_Annoy]

What about an electric gate valve?

[Drenchenator]

I don't know if they make electric gate valves, but even if they did it would be a bad idea. A gate valve uses a wedge to block the path of the water; when it's up their is a fairly, though not completely, straight path through. Gate valves are the ones you hook your garden hose up too.

If an "electric gate valve" used a motor, it would have to turn something many times. If it used some kind of solenoid, it would be really hefty and large. In all, I don't think it would be worth the extra hassle. I couldn't even electric gate valves on McMaster-Carr, so they are pretty much unavailable.

Using an electromagnet to open a ball valve sounds to complicated. Gearing or pulleys could be used effectively, but they would require a lot of design before hand.

If you want a ball valve to open faster, use a torque arm. It's cheaper; it's less complicated; it's less of a hassle to implement and work with. I don't even really see the need for any complex system to try to solve a small problem that most people could deal with.

[Silence]

McMaster-Carr does sell electrically-actuated ball valves. They're probably good for robots that need to shoot water (because solenoid sprinkler valves restrict flow too much), but there are no guarantees about opening speed. Sprinkler valves can actually open quickly, but once again, they restrict flow.

Don't use anything electrically actuated for speed - they may sound effective, but they usually aren't. Research piston valves (sold as quick exhaust valves) and diaphragm valves (sold as sprinkler valves, but they need to be modified) if you want faster opening speed.

[aEx155]

I think Hunt_and_Annoy was trying to make a quick opening, laminar flow valve....but it's really not practical to use a motor/solenoid or anything else of the like. Like Drenchenator and I said, just use a torque arm.

[Hunt_and_Annoy]

A torque arm is annoying though. If there were a way to reduce friction for the ball, it would become easier.

[Ben]

Originally Posted by aEx155

What were you thinking of, Ben? Would it be a way to relocate the trigger?

It would put the trigger wherever you wanted. Just put a torque arm on the ball valve of appropriate length, get some pulleys and appropriately sized rope, and you're set. Attach one side of the rope to the trigger and the other side to the ball valve, looping it through pulleys as needed. Use a spring or rubber bands to close the valve again. Smaller valves and lubrication may be necessary to get a low force short pull that is ideal in a trigger, but it seems perfectly possibly in 1/2 inch brass valves.

This would work like this water gun but with a better trigger system. Drenchenator had problems with the linear pull not always being perpendicular to the torque arm, thus decreasing the applied force and the possible amount of rotation. With a pulley system you can design it so that it will always be at an angle so there will always be a component of the force perpendicular to the torque arm and the valve can open and close completely.

[aEx155]

Ohh, I see. I was thinking that you would've put some kind of pulley on the valve (you could put it on a brass valve in place of the torque arm) and then have another pulley connected to a torque arm.



Like that.

[Aurum]

As fun as using all these electrically-driven methods would be... i presume theres the risk of mixing electricity and water? probably not a good idea

[aEx155]

If you use the correct type of water (I think it's distilled) then there is no ris of shorting. I think some people have PCs (computers, no pressure chambers ) that are submerged in water, and sometimes oil for effect.