63 replies to this topic

[gaspen]

So I was thinking more !  I am pretty deep in this discovery but now I understand how does it work

 

I know it is not as new for you  as for me   

 

 

The machine doesn't need to "watch" each cylinder separately for Dwell value - and it can not do it.

 

When the contact closes at 1st cylinder the ligth on the machine illuminates from 0 to 50 degrees (example) and turns off  beetween 51 and 90 degrees. 

 

The next lobe on the cam will do this again but on the next quarter of the scale as the whole assembly rotates. I see all lights at the same time because it is so fast that my eyes can not senses the difference

[Spider]

I think I'm am following your question here but not 100% sure, correct me if this is not what yr after.

 

Here's a pic of a Distributor under test;-

 

 

You can see here the points are closed (Dwell) for 37⁰ (the fading is due to the action of the camera, to the eye it appears solid). It also has 6⁰ advance at 1950 RPM.

This should be the same in all 4 quadrants. If it's not then it can indicate some of the issue mentioned in my previous post.

[gaspen]

There is no question here I just learned how the machine measure and displays the Dwell angle   

 

My numbers (0-50 and 51-90) are only theoretical, not actual numbers. My 0º equal 130º in your machine, where the contacts open, my 50º is your 93º where the contact closes and so on

 

 

I studied the operation of that french machine, I've found forums about it. Common practice that they replace the original 400V strobe tube for 12V LED's

 

Next I have to learn how it light up a LED with an open circuit. I bet there is a simple solution 

[68+86auto]

As you've found, most used a strobe of some kind. These usually didn't display the points open time using the light since they only flashed once for each cylinder. Some LED conversions work like that and some show the dwell as the unlit section. Some conversions are switchable. The dwell doesn't really need to be seen like this as what you are looking for is that all four firing points are 90 degrees apart. If these are even, the dwell will be too. It does help to display the dwell though as it is clearer than looking at an analog dwell meter and never will need calibration due to how it works.

Many people change to LED simply because they find the strobe dim, this depends on the machine as some are better than others.

I'd suggest reading the manuals of a few different machines.

 

Here's two which are both the single strobe type, not LED

 

https://www.starchak.../sun manual.pdf

 

https://archive.org/...raph-410-manual
 

I have a page on an LED type which I can scan later.

 

There is no question here I just learned how the machine measure and displays the Dwell angle 

 

My numbers (0-50 and 51-90) are only theoretical, not actual numbers. My 0º equal 130º in your machine, where the contacts open, my 50º is your 93º where the contact closes and so on

 

 

I studied the operation of that french machine, I've found forums about it. Common practice that they replace the original 400V strobe tube for 12V LED's

 

Next I have to learn how it light up a LED with an open circuit. I bet there is a simple solution 

 

My machine is one of the last "old" distributor machines made so uses an LED to display the points open time (dwell being the unlit section).

 

My machine has a 15v transformer which is rectified to about 20VDC. To power the strobe circuit and simulate a load for the resistance test, this goes to the points thru a resistor. The strobe supply is fed from the points wire. When the points are closed it's at 0v, when they open it's at 20VDC. It's just like an ignition system but a resistor instead of a coil. I haven't pulled my machine that far apart but I'm told on the disc it has the led and a transistor which are powered inductively.

I have the schematics for a couple of strobe type machines, no LED ones. They all use parts which are hard to get so it's probably best to design a new board and for an LED. 

Edited by 68+86auto, 21 November 2024 - 01:13 AM.

[gaspen]

As you've found, most used a strobe of some kind. These usually didn't display the points open time using the light since they only flashed once for each cylinder. Some LED conversions work like that and some show the dwell as the unlit section. Some conversions are switchable. The dwell doesn't really need to be seen like this as what you are looking for is that all four firing points are 90 degrees apart. If these are even, the dwell will be too. It does help to display the dwell though as it is clearer than looking at an analog dwell meter and never will need calibration due to how it works.
 

 

Yes, that makes sense, thanks for simplifying  

 

From practical view : these machines have the light fixed on the rotating disc, I guess the wires go there through some kind of slip ring. There is many types out there, I can find a suitable piece

 

 original.jpg   22.14K   0 downloads

 

Another idea came to mind when I woke up this morning : what if I place 4 fixed LEDs around the rotating disc, placed 90-degrees to each other ?

 

 elosztó.jpg   11.14K   0 downloads

[Spider]

My machine does have a slip ring, but only a single LED.

 

I think you'd only want one LED.

[gaspen]

My machine does have a slip ring, but only a single LED.

 

I think you'd only want one LED.

 

Maybe I was not clear enough 

 

Yes, your machine uses the slip-ring with one LED  and that LED will light up 4 times in 1 rotation. 

 

I am not sure how will I install that (or any) slip-ring to my machine so I thinking about different solutions also.

 

 

The whole setup is similar if you'd use 4 stroboscope on an engine with 4 marks on the flywheel.

 

 

The LEDs on my sketch are fixed on the base of the machine, they won't rotate just pointed to the rotating disc. They are switched on/off by the contact in the dizzy *

 

On the base there is also 4 fixed markings** (line or arrow, it"s all the same) 

 

The rotating disc has only ONE marking 

 

The marks on the base will be illuminated by the LEDs at the same moment when the mark on the rotating disc approach to the very same spot.

 

 

* I am thinking about controlling them by 12V NO/NC relay but I am not sure that the a mechanial relay is fast enough for this operation.

 

** Of course I will need more markings for the advance checks, but above I described the initial setup of the machine. I mean : does it work at all ?! 

[68+86auto]

Most of the machines which use a strobe don't spin the strobe from what I understand. I'm not really sure how they work as I haven't seen one in person.

 

A relay would be unsuitable

 

This is a simple diagram of my machine.

 

 image_2024-11-21_212221799.png   50.17K   3 downloads

 

When the points are closed, the voltage is low. When they are open the voltage goes past a point where a transistor tells the LED to turn on.

 

 

All of this is the part that I never got around to designing for the machine I was making. I intended to possibly just use a timing light and setup spark plugs. Not ideal but it was what I was going to start with and progress from there. I had motor coupling issues and before I sorted it out I found a machine so never completed my diy one.

Edited by 68+86auto, 21 November 2024 - 11:33 AM.

[gaspen]

Most of the machines which use a strobe don't spin the strobe from what I understand. I'm not really sure how they work as I haven't seen one in person.

 

A relay would be unsuitable

 

This is a simple diagram of my machine.

 

image_2024-11-21_212221799.png

 

When the points are closed, the voltage is low. When they are open the voltage goes past a point where a transistor tells the LED to turn on.

 

 

All of this is the part that I never got around to designing for the machine I was making. I intended to possibly just use a timing light and setup spark plugs. Not ideal but it was what I was going to start with and progress from there. I had motor coupling issues and before I sorted it out I found a machine so never completed my diy one.

 

Maybe a MOFSET controller will solve this... ?

 

 

In this description you can see some details : the rotating disc has a thin slot where the strobe-tube (which converted to LEDs) lights upwards. 

 

The light source is rotates with the disc, also you can see the slip-ring

 

(Google Translator needed)

 

Souriau, banc d'allumage

[68+86auto]

Maybe a MOFSET controller will solve this... ?

 

Do you have electronics design knowledge?

 

I repair electronics when I need to but can't design them. I wish I could.

Edited by 68+86auto, 21 November 2024 - 12:12 PM.

[68+86auto]

This is a simple diagram of my machine.

 

image_2024-11-21_212221799.png

 

When the points are closed, the voltage is low. When they are open the voltage goes past a point where a transistor tells the LED to turn on.

 

 

 

I just noticed I didn't put the modified diagram I made. VBB is the DC Supply +

 

 distmachine.jpg   32.14K   0 downloads

Edited by 68+86auto, 21 November 2024 - 12:41 PM.

[Spider]

I need to think about your proposal some more, but at a 'glance' if the LEDs are stationary, then the degree wheel would need to spin, so how do you read it when it's wizzing around at 2000 - 3000 RPM ?

 

I recall the circuit inside mine is very simple, if I recall, the 'lamp driver' consists of no more than a power supply for the LED, a slip ring (which I can't recall is single or double pole) and the LED.

[gaspen]

I need to think about your proposal some more, but at a 'glance' if the LEDs are stationary, then the degree wheel would need to spin, so how do you read it when it's wizzing around at 2000 - 3000 RPM ?

 

I recall the circuit inside mine is very simple, if I recall, the 'lamp driver' consists of no more than a power supply for the LED, a slip ring (which I can't recall is single or double pole) and the LED.

 

Okay, just ignore it, I  overthought it    I will go for the slip ring version with one LED on the rotating disc

 

Now I hunting for a good 12V motor but it is harder to find that I imagined.

 

There is more 24V motor, but I will need a power supply

 

Most slip rings have the contacts on their sides. How do you call in english which have the contacts on the face ?

Attached Files

•  Képkivágás.JPG   34.16K   0 downloads

Edited by gaspen, 22 November 2024 - 11:31 AM.

[68+86auto]

Use a mains (AC) powered motor and a speed controller.

Alternatively a common motor to find is a treadmill motor which can usually be found for free. They are 180V DC. If you don't mind messing with all the settings you can use the treadmill control panel. It will even regulate the speed. Some cheap basic treadmills have a simple controller with a potentiometer but they are much harder to find. A treadmill motor is way more than enough power but the price is perfect.

 

For the slip ring assembly, simply have a google search. I get a lot of results from Aliexpress which look like they would work. Example https://www.aliexpre...2xoCPfwQAvD_BwE

Edited by 68+86auto, 22 November 2024 - 01:21 PM.

[gaspen]

Use a mains (AC) powered motor and a speed controller.

Alternatively a common motor to find is a treadmill motor which can usually be found for free. They are 180V DC. If you don't mind messing with all the settings you can use the treadmill control panel. It will even regulate the speed. Some cheap basic treadmills have a simple controller with a potentiometer but they are much harder to find. A treadmill motor is way more than enough power but the price is perfect.

 

For the slip ring assembly, simply have a google search. I get a lot of results from Aliexpress which look like they would work. Example https://www.aliexpre...2xoCPfwQAvD_BwE

 

Well my mind was locked to the 12V system as the car uses this voltage 

 

Here we have 230V AC system

 

Why is an AC motor better ?

Edited by gaspen, 22 November 2024 - 02:09 PM.