Topic: SOLVED: si_124 - Krupp - Titan-"Kaffemühle"-"coffee grinder"

[sichel]

@richard fridd: Sorry, I overlooked that i have locked the puzzle for gilescooperuk.
@gilescooperuk: It is still locked for today.

[gilescooperuk]

You can unlock it

[sichel]

Thank you, unlocked

[richard fridd]

Cummins system?

[sichel]

No.

[sichel]

Now the professionals have to get to work.

[fromwien]

"Kaffeemühle", Krupp Titan compressor-engine-brake for 2-stroke diesel. The crank is used to adjust the camshaft and the opening time of the exhaust valves. Yes: It is a two-stroke engine with exhaust valves!

[sichel]

I could not have described it any better And again a point for you.

[fromwien]

I tried to translate the working principle in (readable?) English:

Compressor – brake:
At the drive gear end of the camshaft, is an engine oil pressure controlled double rotary vane piston located, which turns the camshaft drive gear in its opposite direction.  The camshaft is adjusted, that the control times of the exhaust valves are brought forward. This causes, that the exhaust valves already open, when the pistons approximately reach the top dead center.

Working concept of the Compressor-brake

Going downhill, at first you use the engine as a brake compressor, by turning the injection pump to stop position. So the engine is off, only pushed by the rolling vehice. In this state, the braking effect is relatively small. Additional engine brake power then comes by  using of the camshaft compressor brake, operated by the rotating lever, more or less twisted in relation to its drive gear.
This will open the exhaust valves prematurely. The compressed air flows unused into the exhaust and all the engine’s compression work is lost. An extremely strong braking effect is achieved, by no throttling of the exhaust and this without heat accumulation.
When driving downhill, 2 gears higher could be selected with the compressor brake activated, than without using it.

[fromwien]

Again a trial, to explain the working principle of the Krupp 2-stroke diesel engine (Titan: 2x 3-cylinder-2-stroke-diesel):

Krupp 2-stroke diesel with direct current flushing and 2 exhaust valves per cylinder:

As long as the piston moves in the lower area of the cylinder, the piston provides cylinder flushing slots free. With a slight overpressure of 0.55bar, scavenging air flows through the slots from the wash cabinet and pushes -because at this time the exhaust valves are also open - the combustion gases in front of them to the exhaust, while filling the cylinder with fresh air. Shortly after the piston going up by covering the flushing slots again, the exhaust valves close. Fresh air gets compressed. When the piston has almost reached the top dead center, fuel will be injected.  The hot compressed air then burns. The combustion pressure catapults the piston back down. While the piston moves down, the outlet valves open and allow the existing overpressure to flow out. A little later, the piston releases the flushing slots and fresh air flows in through the flushing slots. The same process starts again.

[fromwien]

By the way: Thank you very much for the point!
And much more, thank you so much for the puzzle at all!!! It's only possible to find such a puzzle, with very high technical knowledge

[Carnut]

Hey, I have one of those trucks Sichel!

[sichel]

Very nice! Engine brake is working? The model cars are a great idea!

"Titan" and "Mustang", the little brother

[fromwien]

I think, the best available Krupp-Titan-model (1/43 scale) is this one from 'Schuco'! Picture taken in our model car showroom

[sichel]

I like my sixty years old Wiking Thermozug very much. But the Siku-Titan looks really great.

[Carnut]

Indeed it's very nice.
But the Märklin model was really only intended as a toy, in the days when such die-cast toys were very well detailed and accurate; and they were not particularly expensive.
Nowadays you have to buy a proper 1/43 model to get something accurate and realistic, at a much higher price...

[sichel]

Carnut, of corse there are more details in 1/43 models. But there are some models in my collection I have played with as a boy, also some unglazed specimens. So they have a very special meaning for me and and so, over the course of time, a vehicle museum on a scale of 1/87 could be created in a showcase.