looking for a 12 volt DC push/pull solenoid

[davidbenjamindix]

im trying to find a couple of decent 12volt DC push/pull solenoids. i don't have a ton of money to spend, so im asking for suggestions where i should look. i have a 12 volt motorcycle battery charger for the DC power source, and a 4 channel 12volt DC remote control which I plan on using for the on/off switch.

 

[Reloadron]

You don't mention the needed stroke or force? The bottom of this link may give you some ideas. The linked to solenoids are just an example as plenty of much lower cost units can likely be had. However, things like stroke, force, shaft diameter are important.

Ron

 

[Ross Craney]

Try an auto wrecker. The locking solenoid for a central locking system should do what you want

 

[davidbenjamindix]

i guess i don't know if i should be looking for intermittent duty or continuous? why would i want intermittent duty if it tends to overheat and fail?>

 

[BrownOut]

Because it would be intended for intermittent use, so it wouldn't overhead and fail. If your application isn't intermittent, then don't use a unit that's intermittent duty.

 

[davidbenjamindix]

so intermittent would be used for a faster (more forceful) movement??

 

[Reloadron]

i guess i don't know if i should be looking for intermittent duty or continuous? why would i want intermittent duty if it tends to overheat and fail?>

You choose the solenoid based on its intended application. You haven't shared the game plan for the solenoid? What exactly are you trying to do?

Ron

 

[BrownOut]

so intermittent would be used for a faster (more forceful) movement??

NO. Intermittent means the duty cycle would be low. For example, the door lock solinoids mentioned earlier. The are only actuated a couple times a day, and only for a short period each time.

 

[shortbus=]

These are the door lock actuators; DOOR LOCK ACTUATOR | AllElectronics.com They are like the ones used in GM cars. They use a small motor and a rack&pinion to move the plunger. The only time they are powered is when they are moving, the rest of the time they don't use any power.

 

[davidbenjamindix]

im planning on using the solenoid on a woodworking project to lock/unlock a door. i will attach a rod/bar with a pivot about 1/4 of the distance of the rod, so the small movement from the solenoid with give a large movement on the other end of the rod.

 

[davidbenjamindix]

shortbus: using the equipment i mentioned in my first post, and using the door lock actuator (that is what i want), what do i have to do in order to reverse the polarity going to the actuator?

 

[Reloadron]

shortbus: using the equipment i mentioned in my first post, and using the door lock actuator (that is what i want), what do i have to do in order to reverse the polarity going to the actuator?

If you go that route, then an "H" Bridge could be considered to reverse the polarity going to the solenoid coil. A Google of H Bridge should get you going. Beyond home brew (build it yourself) there are also H Bridge ICs out there. If this is just a momentary affair a DPDT (Double Pole Double Throw) switch could be uses, similar to how it is done with automotive applications. Pretty common switch. If this is a full size door, there are electric door strikes.

Ron

 

[davidbenjamindix]

i decided to use an actuator. the car mechanic ive been going to for a while wrote a note to himself. the next time he changes the actuators on a door lock/central lock system, he's going to give me the actuators/solenoids for nothing. that way i won't have to buy anything. yay.

 

[shortbus=]

i decided to use an actuator. the car mechanic ive been going to for a while wrote a note to himself. the next time he changes the actuators on a door lock/central lock system, he's going to give me the actuators/solenoids for nothing. that way i won't have to buy anything. yay.

That is free but there's usually a reason that there being replaced, there worn out or broken. But it's your project and you know what it's worth I'd go with the ones I linked to and get new ones you won't have to worry about.

 

[davidbenjamindix]

that's true...thanks shortbus. i think i may still order just to be safe. thanks for your suggestions.

 

[gary350]

Those things are rated in ounces and lbs of pull. If you want a push/pull solenoid buy 2 and connect them end to end. Energize one it pulls in that directions, then energize the other one it pulls in the other direction. About 20 years ago I bought a solenoid with 1 lb of pull it was 120 VAC and cost me $30. Every time I turned it on it sounded like someone hit a piece of steel with a large hammer, BOOM. WOW it was loud. I used a small one to build this silly little electric engine. Check out the video.

https://www.youtube.com/watch?v=0409VZP6Ioc

 

[davidbenjamindix]

thanks for the video! that's great! i didn't know solenoids open and closed that quickly!? what i mean to say is, i thought solenoids just opened and stopped, then close and stopped. i didn't figure they would cycle like in your video. that's incredible.

 

[ChrisP]

As was already said, the difference between a continuous duty and an intermittent duty solenoid (or relay, for that matter) is that a continuous duty device has been designed for just that - continual current flow. In addition, most continuous duty solenoids have two activating coils - one is the "pull-in" coil while the other is the "hold-in" coil. This is because it takes more effort to move the solenoid plunger than to keep it in its "moved" position. There is often some sort of internal switch to open the pull-in coil circuit once full plunger motion has occurred.

The simplest way to understand the difference between a continuous duty and an intermittent duty solenoid application might be to consider the mechanism that the solenoid is intended to operate. Once moved, will the mechanism tend to remain in that position, or will it have the tendency to return to its original (or some intermediate) position? If the mechanism will reliably remain at rest once moved, than an intermittent duty solenoid should suffice. Otherwise, either a continuous duty solenoid or some sort of latching system will be necessary.

Continuous duty solenoids will require more complex control circuitry...

 

[Robert Milton]

how to

here is a question i have been wrestling with, how do i control the extended shaft coming out of an actuator or solenoid for 2 different settings or 2 different length so that i can apply 2 settings of pressure to the targetted plate or lever. [stepper motor or logic controller would be too expensive of my use],...thanks

 

[dr pepper]

Central locking solenoids can either be a solenoid or a motor/gearbox.
Also some cars have a electrical servo that controls the fresh air/recycled air control, these are similar to a r/c servo but bigger and have a switch to stop the motor on each limit.
If you want something with a lot more shove then you could modify a wiper motor assy, the output from some motors connects to a rod via a balljoint, very usefull for connecting to a project.