Daimler Benz DB 628

[jerryw]

Above is a drawing from a patent filed by Daimler-Benz designer, Reinhold Freitag in 1943.

It shows the front of the DB 628 engine which was distinctive in that the first stage supercharger was mounted between the propeller reduction gear and the propeller.

(3) indicates the crankshaft with (5) the crankshaft pinion which drives (6) the reduction gear. To the left of (5) is a cushion drive (14) to protect the large gear (15) from shock. Gear (15) drives gear (16) which is directly connected to the planet cage (18) - this is the step-up gearing for the supercharger impeller (9).

Air is fed to the impeller via an annular duct (25) and the volume and direction of the air is controlled by a ring of variable inlet guide vanes (28).

The propeller blades have their pitch set by the mechanism (40) in the bell chamber under the influence of control rods (41) and (42).

The DB 628 was a derivation of the DB 605 version.

 

[Crimea_River]

Interesting. Did it ever see service?

 

[johnbr]

I readied they only made about 50 of them.

 

[Aaron Brooks Wolters]

Do they have any power specs and also, what aircraft might this have been for?

 

[johnbr]

I have read takeoff power was 1,475HP at 2'800r.p.m climbing hp 1310,HP 1,110HP at 2600rpm 36,800ft.Fuel consumption .474 ib./hp./hr maximum cruising at sea level.It is said to have been tested to 52,000ft

 

[razor1uk]

The engine mounting arms, remind me of He-111 style ones. Maybe was tested in FW190H/D/Ta-15*, but the mounting connections spacing seem Me-109 type, and it would be wore likely tested/used in the 109 high altitutde development/testing program.

 

[Aurum]

Thanks for interesting material Indeed DB 627, 628 629 where very curious design. Could you tell where it is from? In neighbor topic there was the list of DB projects. It is really pity that at least the simplest of them were not realized.

 

[davebender]

Daimler-Benz in the Third Reich - Google Books
According to the above link, Daimler-Benz dragged their feet on mass production of the larger DB603 V12. Instead they placed a lot of emphasis on futher development of the DB605 series. Given another year they may have been proven right. The 2,000hp DB605DC had an outstanding power to weight ratio.

Not sure where that leaves the DB628 variant though. I suspect it would be superceded by the planned DB605L which also produced 2,000+ hp and had a two stage supercharger for superior performance at high altitude.

 

[johnbr]