Anybody have experience with small solenoids?

  • Thread starter Thread starter M-Funf
  • Start date Start date
  • Tags Tags
    Experience
Click For Summary

Discussion Overview

The discussion revolves around the design and application of small solenoids, specifically those with a maximum diameter of .125 inches and a length of approximately 1 inch. Participants explore various aspects including suppliers, custom manufacturing, design considerations, and the materials involved in creating effective solenoids for a specific project that requires precise actuation.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant seeks advice on small solenoids, asking about suppliers and the feasibility of building one using magnet wire and a power supply.
  • Another participant suggests that the plunger material, such as steel, may influence the force generated by the solenoid.
  • There is a discussion about whether the coil void should be filled entirely with the plunger or if an air gap is acceptable.
  • A participant mentions the need for the solenoid to be normally off and expresses a preference for pulsed power to minimize heating.
  • Concerns are raised about the response time of the solenoid, with a target of approximately 15 seconds for actuation.
  • Another participant introduces the concept of Ldi/dt, explaining the potential for high voltage spikes when interrupting current flow through an inductor.
  • There is a question about how inductive coils can cause shocks to patients, prompting further clarification on the topic.

Areas of Agreement / Disagreement

Participants express various viewpoints on the design and functionality of small solenoids, with no consensus reached on specific design parameters or materials. The discussion includes both agreement on the need for pulsed power and differing opinions on the implications of inductive effects.

Contextual Notes

Participants note the importance of the solenoid's housing and the potential effects of the solenoid's operation within a human body, indicating a need for careful consideration of design to avoid overheating and electrical shocks.

Who May Find This Useful

Individuals interested in small solenoid design, particularly in medical or precision applications, as well as those exploring custom manufacturing options for specialized components.

M-Funf
Messages
5
Reaction score
0
Hey Guys,
I'm new here, this is my first post. I am a member of other message boards, but they are primarily for fun. I think this board may acutally help me out with some of the work "opportunities" I run into now and again.

First, I should tell you that I'm a ME, not an EE, so although this may sound simple to you, it's a stretch for me. I'm working on a project that requires a very small solenoid. By "very" small I mean that the max diameter is about .125". The length is not as important, so I'd say it could be 1" long. It will be powered by DC batteries. We're still trying to determine how much power will be available to actuate the solenoid. The plunger only needs to move .1" or so.

So, now my questions:
- Does anybody have experience with small solenoids?
- Are there any suppliers that make them this small?
- Are there any suppliers who can custom make them this small? (and have experience doing so)
- Can I design this myself and build it using simple magnet wire and a power supply?
- What type of core/plunger material will generate most force?
- Is it better to fill the entire coil void with plunger, or can there be an air gap/space between them?

As you can see, I'm a total rookie with respect to this particular component. Any guidance or help you can lend me would be greatly appreciated.

Thanks, in advance.
 
Engineering news on Phys.org
M-Funf said:
Hey Guys,
I'm new here, this is my first post. I am a member of other message boards, but they are primarily for fun. I think this board may acutally help me out with some of the work "opportunities" I run into now and again.

First, I should tell you that I'm a ME, not an EE, so although this may sound simple to you, it's a stretch for me. I'm working on a project that requires a very small solenoid. By "very" small I mean that the max diameter is about .125". The length is not as important, so I'd say it could be 1" long. It will be powered by DC batteries. We're still trying to determine how much power will be available to actuate the solenoid. The plunger only needs to move .1" or so.

So, now my questions:
- Does anybody have experience with small solenoids?
- Are there any suppliers that make them this small?
- Are there any suppliers who can custom make them this small? (and have experience doing so)
- Can I design this myself and build it using simple magnet wire and a power supply?
- What type of core/plunger material will generate most force?
- Is it better to fill the entire coil void with plunger, or can there be an air gap/space between them?

As you can see, I'm a total rookie with respect to this particular component. Any guidance or help you can lend me would be greatly appreciated.

Thanks, in advance.
does it need any special outer case ? or can you just leave it with the wire exposed?
Looking at a solenoid i took apart recently i see that the plunger part seems to be made of steel, with an aluminum rod coming out of one end and a nylon rod coming out the other..
i would make it myself if i were you.. because it seems to be a special part that you need..and the smallest one that i have seen before is about .375 '' dia.
your plunger would need to be about .060'' ..
what kind of force is required by your solenoid ??
does it need to actuate something , like a microswitch?
or does it need to be normally off??
 
willib,
The solenoid will be housed inside a Titanium housing, so it doesn't need any additional housing. It would need to be normally off, and I'd prefer pulsed power to energize.
The solenoid will be moving a small pin as a "release" mechanism. The force required to move the pin has yet to be determined, but will be very small.

I'm leaning toward building this solenoid myself within the housing that exists. By doing so, I can make it .23" diameter and have the coil around some other things on the inside (not effected by field created). I'm hoping this will give me more room for the solenoid, and more room for wire density.

cheers!
 
M-Funf said:
willib,
The solenoid will be housed inside a Titanium housing, so it doesn't need any additional housing. It would need to be normally off, and I'd prefer pulsed power to energize.
The solenoid will be moving a small pin as a "release" mechanism. The force required to move the pin has yet to be determined, but will be very small.

I'm leaning toward building this solenoid myself within the housing that exists. By doing so, I can make it .23" diameter and have the coil around some other things on the inside (not effected by field created). I'm hoping this will give me more room for the solenoid, and more room for wire density.

cheers!

how fast does it have to respond ,when energized?
pulsed power is the way to go , because you could pulse it with a lot higher voltage ,than the coil could withstand for a sustained amount of time..
 
response time.

I would think that it should respond or complete it's movement (approx. .10") within 15 seconds. Any longer and the user will become impatient.

I, too, like the pulsed application of power. I don't want this device to get too warm since it's inside the human body...
 
thats very different , i was thinking it was something else..
i suppose that if you create a decaying exponential pulse you could keep from shocking your patients with the Ldi/dt from the coil when you turn it off..
 
Please explain "shocking the patient with Ldi/dt"?

I have some experience with generating muscle motion from low freq. AC and DC current due to inadequate filtering of the output on an Electro-Cautery unit, but how does an inductive coil shock the patient?
 
all i meant was if you abruptly interrupt the current flow through an inductor ,you could create a large voltage ..V=Ldi/dt..
but if you use a decaying exponential as your pulse there should be no problem..and since you have plenty of time (15 seconds is a lifetime..)
so your pulse would rise up to your 'ON ' voltage then decay at a slower rate..
 

Similar threads

Need an electromagnet to play Chess
  • · Replies 37 ·
2
Replies
37
Views
5K
Help with linear solenoid calculations (engine valve actuators)
  • · Replies 15 ·
Replies
15
Views
3K
Neat windings vs sloppy windings for Solenoid Actuator?
  • · Replies 4 ·
Replies
4
Views
3K
Solenoid Lift Force Results -- Need Data Analysis
  • · Replies 4 ·
Replies
4
Views
6K
Graduate What speed v(t) enables constant power by solenoid pull?
  • · Replies 4 ·
Replies
4
Views
1K
Guiding Magnetic Fields in Solenoid Coils: Design and Material Considerations
  • · Replies 22 ·
Replies
22
Views
4K
Actuating Pencil To Draw Waveforms
  • · Replies 16 ·
Replies
16
Views
2K
Boosting AC Signal for Solenoid: Techniques for Current Amplification
  • · Replies 3 ·
Replies
3
Views
2K
Question related to circuit for actuating Fuel Injector
  • · Replies 10 ·
Replies
10
Views
2K
Minimum solenoid activation time?
  • · Replies 8 ·
Replies
8
Views
4K