damper a solenoid?

[spondootre]

I am going to be using a solenoid in a toilet flushing project, it moves too quick for my purposes, 0mm - 30mm in 30ms I want to damper that somehow using perhaps a hydraulic/pneumatic contained damper to slow it to apprx 1second Does anyone know where I could look to find that sort of thing in the UK? I've tried a couple of places but can't find anything, perhaps i'm searching for the wrong thing, any suggestions?

Malc

 

[stevez]

I think that most appliances in US are supposed to have valves, solenoid or otherwise, that operate in a way that reduces water hammer. I would expect that to be the case in UK. The valves on dishwashers or clothes washers are likely to be electric operated solenoids with the slow closing feature.

 

[spondootre]

Sorry if I wasn't clear, it's not a solenoid water valve but just a normal push solenoid which is going to push the flushing mechanism, it's just that it will travel to hard and fast for smooth operation of the existing system.

 

[stevez]

Small Parts Inc site shows dashpot snubbers that might do the trick. Google on dashpot alone - or snubber alone - or together.

Can you come up with a circuit that slowly (over a total of 1 second) increases the current to the solenoid?

 

[spondootre]

Excellent, that looks like the sort of thing exactly!! I'll have a look for a UK supplier now i've got a name for it!!

Thanks

 

[HiTech]

pinball machines use damped solenoids. Slip a spring of desired coil strength over the plunger. At the base of the solenoid's plunger hole, you can glue a small rubber grommet so the plunger hits softly. Spring tension can be adjusted by stretching it or compressing it trial & error to get your desired effect.

Or go visit an arcade or vending machine company. Often they have spare solenoids on hand that you can get for free or cheap.

 

[evandude]

if you aren't restricted entirely to a solenoid, you might be able to use something like the cheap linear actuators you can buy for adding electric car door locking. They have a lot of throw, are slower than a solenoid to begin with, and you could probably slow them down further with PWM, or gear reduction if you wanted to get fancy.

 

[spondootre]

I hadn't thought of central locking actuators, I would be able to return them electrically also. I'm just not sure of the distance they travel, I'll go and get one tomorrow and experiment.

Cheers

 

[ClydeCrashKop]

You can get all the adjustable dash pots you want from carburetors at the junk yard or you can use a PIC with PWM to flush slowly.