Solenoid engine Build

Gallery, Projects and General > Project Logs

<< < (10/15) > >>

SPiN Racing:
Beautiful build, and exciting project!

I was a arcade manager in the late 80s, and early 90s when in college and a bit beyond, and ended up traveling all over ehe state of Florida repairing pinball machines for the arcade company I worked for.

I still have a handful of the Solenoids we used to use for pinball machines, and seeing this made me seriously consider putting one of these on the back burner.

I actuallymade a electromagnetic rail gun of sorts from coils back then. Basically it was a board with 8 coils in a line, wired with optical switches, so that when the metal shaft broke the optical sensor the next coil in line was energized, and drew the rod into it. When the rod passed far enough into it, the coil turned off and inertia carried it through to break the beam on the next coil, energizing it.

In the end it would shoot the rod that was attached to the pinball flippers across the arcade with enough force to stick it into the cedar 1" paneling 30 feet away.

With regard to your engine, as others have mentioned it sounds as if its energizing whenever the piston is anything OTHER than TDC.

I would think you simply need to set up a relay that closes when the engine is at BDC, and then once it hits TDC, or a bit before, it Disengages the relay.. so the coil is no longer energized while its traveling to BDC.

Scott

AdeV:
Firstly - congratulations on a beautifully built machine! You've got some excellent skills there, many of them I'd like to learn myself...

So, have some of these: :bow: :bow: :bow: :beer: :thumbup: :clap:

A thought as to why it's not running:

Your activation system is turning the solenoid on both as the piston is going down into the solenoid, and as it is pushed back out; ISTM that the solenoid is doing its best to stop the engine on the in stroke; and obviously can't push hard enough to overcome both that & the friction on the out stroke. Since your net energy input from the solenoid is, effectively, zero; what you're seeing is the energy imparted to the flywheel being lost to friction.

IMHO you need to alter your activation system so it doesn't "fire" on the side-shaft down-stroke (piston in-stroke). I can think of 2 ways to do this:

1) Profile a bar so that one side allows the switch to operate, the other side doesn't. at the end of each stroke, have a mechanism that causes the bar to turn by 90 degrees, anticlock at one end, clock at the other; so the bar presents a different profile each stroke (but the same profile each up stroke & the same profile each downstroke). If it's as difficult to machine as it is to describe, it's probably quite a tricky one.... OTOH, it gives you a way of hooking your governer up; if the engine is above the governer shut-off speed, the bar-twisting mechanism is moved out of reach; so the "non active" side of the bar is always presented to the engine; as it slows, the twister drops back into place, allowing the solenoid to "fire" again.

2) Arrange the switch shaft to travel at half the speed of the crank shaft, just like a real IC engine camshaft does. You'll still need to find some way of making it "fire" at different points on the up & down stroke (of the side shaft), though...

DaveH:
Al,

what a great post. :clap:

Beautifully built engine .... incorporating great skill coupled with a lot of know how. :clap: :clap: :clap:

Thanks Al I really enjoyed it. :D

:beer:
DaveH

CallMeAl:
First of all, thanks everyone for your comments and words of encouragement. Sorry for the slow reply, but I have distant family in town and an somewhat occupied for a few days.

I appreciate the suggestions and advice on how I might over come the problems with the design on the switching on this motor.

Some answers to questions:

cfellows: the cams close the switch.

Jamie & David D: Yes, it fires at each end of the stroke for I am trying to an impulse at each end of the stroke (double acting). I'll elaborate on my thinking in another post later in the next couple of days. Unfortunately the cams currently are actuating the switch just prior to TDC and BDC so I was hoping the momentum of a heavy flywheel would carry the piston over center and the coil impulse would pull it back until the cam released the switch. Hey, i said it was experimental! :loco:

AbeV: Interesting suggestions

John Hill: When I started this I stated I new enough about electricity to be dangerous :zap: and I still stand by that statement.

Rob & DaveH: Thanks for your nice comments.

Scott & Tom: As I said, I will try to explain my thinking on the solenoid, piston, switch arrangement in a following post, thanks for your interest.

I'm going to play around more with the timing on this thing this weekend and try a couple of other things before I totally give up on this thing, but not too long for I have another project in mind and am itching to get on with it.

John Hill:
Al, unfortunately I dont think you can get double action from an AC solenoid.

My suggestion is to adjust your timing so that the switch is closed for the entire 'in stroke', that would be the most simple configuration and would be a good starting point. IMHO of course.

Navigation

 Message Index

Go to full version