[Weter]

Fig.2 need ARs on release state to be painted red?

Quote

two-chamber air brake. This system did not require a triple valve, but was generally slower in operation.

Very interesting.
Actually, here BC have combined TW function of brakes actuation/release inside itself! Definitely, due to larger cpvolume, it had slowly response, so smaller piston, between two chambers, propelling slide-valve have been migrated to triple-valve separate (or integrated with cylinder) case.
Fig.3
Spring and vent-off valve are needed to be shown.

So, yellow is for steam?

For twin-pipe systems, is there sense to show AR/BC air in rose, since BP is only for signal propagation, while air is being taken from blue feeding magistral?
In pneumatic diagrams, compressors are shown by O> symbol, check valve - =o>=, cocks as =>|<=, taps as =>T<=
Fig5.
Equalizing VALVE instead Res, maybe?

[darwins]

Weter, on 04 February 2023 - 02:31 AM, said:

What does that mean there?

It means each wagon has its own control. Like handbrakes. The driver can not apply the brake on the whole train.

Continuous brake = pipe (or chain or cable or electric connection) that runs along the train and can be controlled for the locomotive.

[Weter]

How can air brakes be non-continious? On locomotive only?

[darwins]

Good question! http://www.elvastower.com/forums/public/style_emoticons/default/discuss_gathering.gif
Each braked car had a compressor that was driven from the axle.

The air was stored in a reservoir.

The guard or brakeman opened a valve to let the air into a brake cylinder to apply the brake.

[Weter]

We had first trams with mechanical-driven by axle compressors.
No move-no air. Same as early American steamers with rod-driven feeding pumps, before injectors invention.
Feeding a boiler caused crew to uncouple engine from train and make a short return ride there and back.

[darwins]

So onto vacuum brakes...

It is said that in 1844, Nasmyth and May, (UK), invented a non-automatic vacuum brake.
The first practical vacuum brake systems appeared around 30 years later.

1872 - Smith vacuum brake, USA, continuous non-automatic vacuum brake, used by some railways in UK.
1875 - Hardy vacuum brake, Austria, (improved from Smith vacuum brake) continuous non-automatic vacuum brake, used by railways in Austria.
1876 - Eames vacuum brake, USA, continuous non-automatic vacuum brake

https://i.imgur.com/9p0pqWf.jpg

The first automatic vacuum brakes appeared shortly afterwards.

1877 - Clayton-Hardy automatic vacuum brake, UK + Austria, used by railways in UK, Austria, Spain, Portugal, Sweden, Denmark, Bosnia and Herzegovina, Serbia and Bulgaria.
1878 - Automatic vacuum brake, Aspinall UK
1878 - Automatic vacuum brake, Gresham UK
1879 - Automatic vacuum brake, Sanders USA - including direct admission valve

https://i.imgur.com/qygoXxP.jpg

All of these were two-chamber brakes. (Compare to single chamber and two chamber air brakes already described.)

As a result of competition from the Westinghouse brake and the Automatic Vacuum Brake, Eames produced the Duplex brake.
This combined both a direct and an automatic vacuum brake. (Compare to the Westinghouse-Henry double brake.)

https://i.imgur.com/2on1yjb.jpg

Aspinall also fitted a two pipe vacuum system to some locomotives in Ireland, but I have no details of that system.

Independent brakes when used on steam locomotives were steam brakes:

https://i.imgur.com/PZYCGvm.jpg

Independent brakes when used on diesel or electric locomotives were air brakes:

https://i.imgur.com/HzW0dPG.jpg

In South Africa (c. 1947?) an Electro-Vacuum brake was invented for electric multiple unit trains.

https://i.imgur.com/V7P37ko.jpg

In the 1950s Gresham and Craven produced a twin pipe vacuum system for diesel multiple units.

https://i.imgur.com/EVLAfcF.jpg

A final attempt to improve the vacuum braking system was to add an Equalising Reservoir.
The Vacuum-EQ system was fitted to some diesel electric freight locomotives in UK in the 1960s.

https://i.imgur.com/UNckV7s.jpg

[Laci1959]

https://kephost.net/p/ODU4NzQ2.png

Hello.

A picture today of using a "Westinghouse Henry brake". The yellow colored hose is the extension of the auxiliary brake (locomotive brake) towards the cars. I put it in quotation marks because it is not operated by the train brake or other brake lever, but by the auxiliary brake (locomotive brake).
On the Children's Railway, children aged 10-14 perform the service under adult supervision.

Sincerely, Laci1959

Image source internet.

[darwins]

Laci1959, on 04 February 2023 - 11:38 AM, said:

Hello.

A picture today of using a "Westinghouse Henry brake". The yellow colored hose is the extension of the auxiliary brake (locomotive brake) towards the cars. I put it in quotation marks because it is not operated by the train brake or other brake lever, but by the auxiliary brake (locomotive brake).
On the Children's Railway, children aged 10-14 perform the service under adult supervision.

Sincerely, Laci1959

Thanks for that. Nice picture.

I forget to include with vacuum brakes, the interesting variations of the Hardy and Körting vacuum brakes used in Austria.

It was not exactly independent locomotive brakes, but the normal service braking was using only the train brakes, with the locomotive brakes used only in emergency.

This is with the direct vacuum brake:

https://i.imgur.com/t6OByp5.jpg

This is later, with the automatic vacuum brake.

https://i.imgur.com/hpDAdbN.jpg

The connecting pipes allowed the locomotive brakes of double headed trains to be controlled from the leading engine.

[darwins]

Weter, on 04 February 2023 - 07:00 PM, said:

You've forgot to show BC in car on release state as two-chamber - on the top ov second diagram.

Thanks. Now corrected. (Too much copy and paste!!)

[Weter]

Enormous work is being done, no wonder.