Dräger Regulators

[antique diver]

Seeing this cool Drager rig made me sorta happy, but I would have been ecstatic if it was mine!

This is in the collection of our good friends at Grapevine Scuba, and I don't think they want to part with it.

[nikeajax]

Bill, aren't those the ones that have a hose-within-a-hose? Totally boss: I wonder how it breathes?

JB

[antique diver]

Nov 20, 2023 12:10:38 GMT -8 nikeajax said:

Bill, aren't those the ones that have a hose-within-a-hose? Totally boss: I wonder how it breathes?

JB

I didn't find any Drager schematics showing a hose within the corrugated hose on any Delphin model. Not sure what noticeable effect that re-breathing the gas trapped within that single hose would really have on a diver, but I would be cautious about it.

The inside of hose didn't really look clean enough to test breathe, so I didn't try it.

[SeaRat]

The only hose-within-a-hose concept ever put into production that I know of is the U.S. Divers Overpressure Breathing regulator, the predicessor to the Mistral. And, it has great breathing characteristics.

IMG_1256 by John Ratliff, on Flickr

I have used it in very trying conditions, and not only is it a great breather, but also it's a very quiet breather. I have put longer, flexible hoses on it, and a new inner hose.

John

[SeaRat]

Here's the Dräger unit, in CG-45.



Here's a drawing of that regulator:



I think we'll have to rely upon DRW or Frank Werthwein to translate this text from German into English:



www.cg-45.com/regulators/Drager/index.shtml

John

[antique diver]

Nov 20, 2023 18:42:40 GMT -8 SeaRat said:

The only hose-within-a-hose concept ever put into production that I know of is the U.S. Divers Overpressure Breathing regulator, the predicessor to the Mistral. And, it has great breathing characteristics.

I have used it in very trying conditions, and not only is it a great breather, but also it's a very quiet breather. I have put longer, flexible hoses on it, and a new inner hose.

John

I agree with your assessment of the USD Overpressure. Mine is also a great breather. It definitely lives up to its name when air is needed, and took a few dives and adjustments to adapt to the airflow characteristics, which can be a little unnerving until you get used to it.

[DavidRitchieWilson]

Nov 20, 2023 18:53:14 GMT -8 SeaRat said:

Here's the Dräger unit, in CG-45.



Here's a drawing of that regulator:



I think we'll have to rely upon DRW or Frank Werthwein to translate this text from German into English:



www.cg-45.com/regulators/Drager/index.shtml

John

German original

DELPHIN II

Mit diesem einfachen und sicheren Gerät ist selbst ein nicht im Tauchen ausgebildeter Schwimmer in der Lage, Tauchvorhaben bis zu 15 m Tiefe leicht und ohne Gefahr auszuführen. Die besonderen Vorzüge des Gerätes bestehen darin, daß Wartung und Inbetriebnahme denkbar einfach sind und der Anschaffungspreis bei geringsten Betriebskosten niedrig ist.

Sein hervorstechendstes Merkmal ist die sofortige Einsatzbereitschaft bei Katastrophenfällen - im Notfall kann das Gerät erst während des Abtauchens angelegt werden - wodurch "Delphin II" sich in ganz besonderem Maße für die Lebensrettung eignet.

Preis kompl. mit 4-Ltr.-Flasche DM 276,—
Preis kompl. mit 5-Ltr.-Flssche DM 292,—

DELPHIN III

Das Preßlufttauchgerät "Delphin III" besitzt zwei 4-Liter-Flaschen. Die zweite Preßluftflasche ist mit einem "Reserveschalter" versehen. Der Schalter wird betätigt, wenn der Widerstandswarner darauf aufmerksam macht, daß der Luftvorrat zur Neige geht. Die dann noch verfügbare Luftmenge genügt zum Auftauchen aus größerer Tiefe. Größte Tauchtiefe etwa 25 Meter. Der Lungenautomat gleicht dem des "Delphin II"-Gerätes.

Preis kompl. mit 2 Flaschen je 4 Liter DM 494,—

English translation

DELPHIN II

With this simple and safe device, even a swimmer who is not trained in diving is able to carry out diving operations up to a depth of 15 m easily and without danger. The special advantages of the device are that maintenance and commissioning are extremely easy and the purchase price is low with minimal operating costs.

Its most striking feature is its immediate readiness for use in the event of a disaster. In the event of an emergency, the device can be donned while diving - making "Delphin II" particularly suitable for life-saving.

Price complete with 4-litre cylinder DM 276.—
Price complete with 5-litre cylinder DM 292.—

DELPHIN III

The "Delphin III" compressed air diving device has two 4-litre cylinders. The second compressed air cylinder is equipped with a "reserve switch". The switch is activated when the resistance warning indicates that the air supply is running low. The amount of air still available is sufficient to ascend from greater depths. Maximum diving depth is around 25 metres. The regulator is similar to that of the "Delphin II" device.

Price complete with 2 4-litre cylinders, DM 494.— each

DRW

[DavidRitchieWilson]

The other two German texts:

German original

Abb. 10 Lösen des Leibgurtverschlusses durch ziehen am Gurtende

zurückbleibende kohlensäurehaltige Ausatemluft wird beim nächsten Einatemzuge mit der vom Lungenautomaten gespendeten Frischluft gemischt erneut eingeatmet.

Die Abmessungen des Faltenschlauches zum Tauchen sind so gewählt, daß der "Totraum" kleiner als bei normalen Atemmasken ist. Infolgedessen bestehen keine Bedenken gegen die Pendelatmung beim Preßluftatmer Modell PA 51 als Tauchgerät.

16. Soll das Gerät abwechselnd als Gasschutz- und Tauchgerät verwendet werden, so kann das zum Tauchen erforderliche Ausatemventil am Lungenautomaten verbleiben. Da es einen höheren Widerstand hat als das Maskenausatemventil, bleibt es bei der Benutzung des Gerätes für den Gasschutz stets geschlossen. In diesem Fall findet also keine Pendelatmung statt.

14 Abb. 11 Modell PA 51 als Tauchgerät

English translation

Fig. 10 Loosen the waist belt fastener by pulling on the end of the belt

The remaining carbonated exhaled air is inhaled again during the next inhalation, mixed with the fresh air provided by the regulator.

The dimensions of the corrugated hose for diving are chosen so that the "dead space" is smaller than with normal breathing masks. As a result, there are no concerns about pendulum breathing with the model PA 51 compressed air breathing apparatus as a diving device.

16. If the device is to be used alternately for gas protection and as a diving device, the exhalation valve required for diving can remain on the regulator. Since it has a higher resistance than the mask exhalation valve, it always stays shut when using the device for gas protection. In this case there is no pendulum breathing.

14 Fig. 11 Model PA 51 as a diving device

1 Preßluftflasche: 1 compressed air cylinder
2 Flaschenventil: 2 cylinder valve
3 Anschlußstutzen 3 connecting pieces
4 Handrad: 4 handwheel
5 Dichtring: 5 sealing ring
6 Schließbolzen: 6 locking bolts
7 Unterhebel: 7 lower lever
8 Schließfeder: 8 recoil spring
9 Oberhebel: 9 upper lever
10 Membran: 10 membrane
11 Faltenschlauch: 11 corrugated hose
12 Ausatemventil: 12 exhalation valve
13 Haltering: 13 retaining ring

DRW

[cg43]

Hello

There is an excuse the "dräger people" made to use only one hose .
Text under Abb.10 and left from Abb. 11

"Die Abmessungen des Faltenschlauches zum Tauchen sind so gewählt , das der Totraum
kleiner als bei normalen Atemmasken ist . Infolgedessen bestehen keine Bedenken gegen
die Pendelatmung beim Pressluftatmer Model PA 51 als Tauchgerät . "

The tranlation :
The dimensions of the corrugated hose are choosen taking into account that the dead space
is less then  that from an ordinary breathing mask (FFM without interal parts) .
Therefor are no doubt's against the pendulum breathing with the model PA 51 as an diving gear .

The max. depth recommended was 25m (82 feet)
This depth belonged to a diver breathing deep and slow as usual for diving in the 1950's as far as I know .

Today diver's are told to breath like on dry land . But this is flat and often .
In this case any additional death space is bad .
This may be an corona mask , a snorkel , a FFM or breathing device .
Death space should allways compensated by deeper breathing .

Greetings   Rainer

Hello David :Found your second translation later .

[SeaRat]

Thank you David and Rainer! I like that explanation of the reasoning for the single hose. Here is a chart of a study of CO2 inside some of the full face masks:

FFM Calculations by John Ratliff, on Flickr
I don't know where I got this, as it was some years ago that I put it into my Flikr photos.

Rainer talked about respiration, and deep breathing:

The max. depth recommended was 25m (82 feet)
This depth belonged to a diver breathing deep and slow as usual for diving in the 1950's as far as I know .

Today diver's are told to breath like on dry land . But this is flat and often .
In this case any additional death space is bad .
This may be an corona mask , a snorkel , a FFM or breathing device .
Death space should allways compensated by deeper breathing .

This makes a lot of sense to me, and I remembered this graphic from the U.S. Navy Diving Manual, March 1970:

USN Lung Volume001 by John Ratliff, on Flickr
Note the difference between regular breathing, at 0.5 liters, and the deeper breathing. It makes a big difference in both scuba and snorkel diving. Using the single hose, holding about the same volume as a snorkel, would work in the depth range stated.

John

[nikeajax]

Actually, the Demone Mk-I & II regs utilized the hose-within-hose idea: it also had a pilot-valve Look at Pgs. 94 & 99 in the second edition of Basic Scuba: the Mk-I was a single hose and Mk-II was a double-respectively, double and quad Utterly whack-a-doodle all the same...

JB

[SeaRat]

This thread developed independently of the “Things that made you happy” thread, and deserved its own thread. So I moved it into its own so we can pursue these regulators.

JB, I’ll have to look in Basic Scuba to see what you are talking about.

John

[SeaRat]

JB, I've looked at the Demone Mk I and Mk 2, and they do have a hose-within-a-hose concept, but it is much different from the U.S. Divers Company Overpressure Breathing regulator. The Domone Mk I was single hose, with an exhalation hose over the single hose. The Mk 2 was a double hose, but what it did was bring the pressurized air to the mouthpiece, which was the second stage. It was a pilot valve, as you state, and as explained by Fred Roberts. But there is an exhalation valve (two for the Mk 2) in the mouthpiece, and the corrugated hose is flooded. What it does is to route the exhalations away from the diver's mouth to his or her shoulders, where it is released. Some biologists have done this for their single hose regulators by clamping a corrugated hose onto the exhalationlexhaust tee ond routing it behind their head. I simply use a double hose regulator.


Here's the Demone Mk 2 regulators.


A parts diagram for the Demone Mk 2


The mouthpiece, with its two second stage valves. Note the small exhaust valves on each side of the valve, and the water inlet opening.



See the full write-up at CG-45's website (thanks Rainer).
www.cg-45.com/regulators/Demone/index.shtml

John

[vance]

Quoting John from above:

"Some biologists have done this for their single hose regulators by clamping a corrugated hose onto the exhalation exhaust tee and routing it behind their head. I simply use a double hose regulator."

They must have used a non-return valve in the end of the corrugated exhaust hose?

[SeaRat]

Nov 22, 2023 10:49:32 GMT -8 vance said:

Quoting John from above:

"Some biologists have done this for their single hose regulators by clamping a corrugated hose onto the exhalation exhaust tee and routing it behind their head. I simply use a double hose regulator."

They must have used a non-return valve in the end of the corrugated exhaust hose?

No, now as I recall, they used bicycle inner tubes over the exhaust tee, and the entire tube was flooded. It just routed the exhaust out behind them. The original non-return mushroom valve was used in the second stage. The entire hose after the second stage mushroom valve was flooded.

John