Force output of Solenoids w/ complicated assemblies
Force output of Solenoids w/ complicated assemblies
(OP)
I'm trying to guage whether or not a solenoid will be able to produce enough force for my intended application. Most commercial solenoids I see sold fail to produce enough force so I was very interested when I read that complicated and hard to assemble magnetic solenoids can attain much higher flux densities than traditional ones.
Because my application does not demand alot of frugality, paying alot for sophisticated solenoids does not bother me immensely. Optimally, what I'm looking for specifically are force outputs in the range of 300 to 550 newtons from a solenoid that is no larger than 3" x 3" x 8" (cm: 7.5 x 7.5 x 20) So my question would be whether anyone with experience in solenoid engineering knows if something like this is possible.
side note: I'm horrible with the numbers and equations at work in electromagnetism, so please feel free to exclude the math.
Thx for the help
Because my application does not demand alot of frugality, paying alot for sophisticated solenoids does not bother me immensely. Optimally, what I'm looking for specifically are force outputs in the range of 300 to 550 newtons from a solenoid that is no larger than 3" x 3" x 8" (cm: 7.5 x 7.5 x 20) So my question would be whether anyone with experience in solenoid engineering knows if something like this is possible.
side note: I'm horrible with the numbers and equations at work in electromagnetism, so please feel free to exclude the math.
Thx for the help





RE: Force output of Solenoids w/ complicated assemblies
How much current you can supply?
How much voltage you can supply?
RE: Force output of Solenoids w/ complicated assemblies
Haven't heard much about them recently.
Mike Halloran
NOT speaking for
DeAngelo Marine Exhaust Inc.
Ft. Lauderdale, FL, USA
RE: Force output of Solenoids w/ complicated assemblies
RE: Force output of Solenoids w/ complicated assemblies
The stroke distance needs to be around 3.5 cm or less
As for the current and voltage, the power source will need to be a battery thats portable enough to tote around. Given that it needs to be portable and small/light, the voltage and current will probably be whatever the best configuration a battery can provide. I'm not real familiar with the kind of power batteries can provide so just assume that the battery provides the optimal output that a battery could provide.
*The battery needs to be no bigger than the solenoid.
RE: Force output of Solenoids w/ complicated assemblies
The solenoid would probably need to operate at around 35%-50% of the time
RE: Force output of Solenoids w/ complicated assemblies
RE: Force output of Solenoids w/ complicated assemblies
Mike Halloran
NOT speaking for
DeAngelo Marine Exhaust Inc.
Ft. Lauderdale, FL, USA
RE: Force output of Solenoids w/ complicated assemblies
TTFN
RE: Force output of Solenoids w/ complicated assemblies
Mike Halloran: don't know what a ballscrew is
RE: Force output of Solenoids w/ complicated assemblies
That deferred, 3.5 cm is a _huge_ stroke for a solenoid, even a big one. You need to look up the force/ stroke curve for a typical solenoid; you don't get the solenoid's rated force for its entire stroke.
The primary reason why the force/ stroke curve follows an inverse square sort of relationship is that the effective air gap increases as the solenoid is moved away from the closed position, and magnetic circuits are exquisitely sensitive to air gaps.
A ballscrew is a special leadscrew with friction- reducing balls between the nut and the screw. They can be had packaged with a gearmotor to drive them. An electric motor's air gap, hence its torque, is not dependent on how far the leadscrew has moved. Hence, if the speed requirement is within the capabilities of a motor- driven ballscrew, that device deserves consideration.
Mike Halloran
NOT speaking for
DeAngelo Marine Exhaust Inc.
Ft. Lauderdale, FL, USA
RE: Force output of Solenoids w/ complicated assemblies
end game purpose is to accelerate a 3 gram object to 90 m/s within a 50-60 ms time frame.
really what im looking for is any knowledge on ultra-high flux solenoids and magnetic assemblies.
RE: Force output of Solenoids w/ complicated assemblies
90m/s*3gm/50ms = 5.4N That's 2 orders of magnitude off from your original post
The bad news is that the acc=183g's, but it requires 1/2acc*(50ms)^2 = 2.25 m
Assuming that your stroke and velocity requirements are actually correct, I get that you need about 12,000g's and a timescale of 780 microseconds.
TTFN
RE: Force output of Solenoids w/ complicated assemblies
F=M*A
and
VF2=VI2 + 2*A*D
902=02 + 2*A*.035
A = 115714 m/s2
F = .003 * 115714 = 347 Newtons
that is using a 3 gram object and a 3.5 cm distance. less distance would be better, but more force would be required, obviously.
That clears the math out of the way, but what im really interested in is info on high flux magnetic assemblies.
RE: Force output of Solenoids w/ complicated assemblies
What you forget is the mass of the moving part of the solenoid (the plunger) which will be hundred of grams to achieve this force from a distance of 3.5 cm which you need to get the 90 m/sec speed. You end up with moving a very large mass compared to the 3 grams.
RE: Force output of Solenoids w/ complicated assemblies
http://home.insightbb.com/~jmengel4/rail/rail-intro.html
RE: Force output of Solenoids w/ complicated assemblies
Per your calculation, you have an acceleration of 115714 m/s^2, this means that 90 m/s is reached in 781 microseconds, not 50 milliseconds. There is no solenoid capable of that kind of acceleration.
To reduce the acceleration requirement is to accept a longer travel distance. Assuming a 50 millisecond acceleration time, you'd only need about 5N and 2.25 m of travel.
TTFN