Check valve prototype

[86rocco]

I got ambitious this weekend and made a check valve for my flowbench, I'm really please with the results, it seems to work great, it leaks a like bit around the screws but a bit of silicone will fix that. Here are a few pictures.


The parts, all pretty normal hardware store items.


The parts before and after being trimmed to fit along with a spacer for the hinge made out of some scrap pvc.


The cap ready to receive the other bits.


The assembled unit.

[Tony]

What a lovely simple idea, I like it.

[Thomas Vaught]

Should work great Ed! What are the rubber parts again and the diameters?

Tom V.

[86rocco]

The rubber part is made from a "flat sink stopper", I didn't know such a thing existed until came across them while browsing the plumbing aisle at a local hardware store yesterday. They're 4" in diameter but I've trimmed them down to about 2 5/8" and the rubber is about 3/32" thick, and the pvc cap I'm using is 4"

[Mousehouse1]

What motors are you using? I am using the 16-1234's. Do you have a picture of them on a motor?

[86rocco]

I'm using Ametek 115923 motors. My motors will be mounted to the dividing wall between the two halves of the airbox and the check valves will be mounted directly on the vacuum side side of the wall. I've got a check valve ready to mount at home, I'll post up a picture of it later today, that should make thing more clear for you.

[86rocco]

As promised, more pictures. I've done a mock-up to show how the valve mounts up in the flowbench. The back half of the valve is another 4" pvc cap with an air hole and 6 screw holes, glued to the cap is a short piece of 4" pvc pipe.


This piece gets held over the air inlet of the vacuum motor with 4 screws.



The rest of the valve slips on over this and gets secured with 2- 5" screws


Missing from these pictures is the o-ring between the two halves of the valve, it's probably not necessary and may be omitted entirely.

[Thomas Vaught]

Now that is SLICK!!!

Only things I would do differently would be:

Start out with a 1.75 hole in the divider board (same diameter as the 115923 inlet hole).

Wrap some sand paper cloth in a slotted rod and
radius the hole out to about a 2.25" opening at the check valve mounting surface.

Open up the check valve rear hole to 2.25 inches
and knock the edge off the hole in the plastic so it blended with the radiused hole in the wood.

Flip the bolts and nuts around on the hinge so that the bolt heads are on the outside. I would try and find round head bolts or screws if possible as the flow from the plenum to the check valve opening will be all around the check valve housing.

Radius the opening at the front of the check valve a little bit with a file.

Great Idea though, goodbye mechanical slide valves for motor control for me!!!

Now I need to hit the Lowes for some parts!!

Tom V.

[86rocco]

I appreciate the input, I'd planned to take a a 1/4" round over bit to the dividing wall and blend the back hole into that. The bolts for the hinge are in that direction because the holes in the hinge are countersunk, the flat head screws help locate the hinge, I don't want to change that, maybe I'll could shorten the screws a little and use closed acorn nuts to help smooth out the air flow a little.

The only thing about this design that I'm not completely happy with are the hinges, they're a little cheaply made and a bit sloppier than I'd like, they bind up quite easily if they get a little twisted, I'm worried that might become a maintenance issue.

[Thomas Vaught]

I thought about the hinge deal too. If I come up with a better hinge that is cheap I will let the board know.

Using a glued on rubber flap would eliminate binding but might fail over time.

Tom V.

[Mouse]

Pop-rivit the hinge.

[86rocco]

[Thomas Vaught]

leave your prototype the way it is for the testing and then when you have a design you like use the rivits, etc.

Tom V.

[86rocco]

That's pretty much what I plan to do. One of the things I really like about this design is that the business end of the valve can be removed or replaced in just a few seconds so test fitting modifications will be very quick and easy.

[Thomas Vaught]

I plan on hitting the Lowes later tomight and scrounge some parts.

Great idea. I wonder how the valve would work with the check valve opening pointed downward and the motor mounted vertically?

Tom V.