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Help with Swedish ordnance "Centralrör"

Centralrör M/37 and M/41 (the Green one) used for Swedish Air Dropped Bombs - the right one in a M/52 used on Napalm bombs by Sweden and shortly by the UK. The series included also the The M/40, here:
Centralrör m 40, blind 022wYzp6Fuw5.jpg
Another look at the M/37, typical of the series:
Centralrör för flygbomb m 1937 012sBXVfiAvf.jpg 032wZ1bvVPUL.jpg

Although looking at first glance these may look similar to the German electrical fuzes, they are in fact totally different and are in fact, to the extent of my knowledge, really unique in their kind,
They are centrifugal lateral fuzes.
If centrifugal nose fuzes for bombs are common and were in fact among the first ones to be developed (most of the PuW nose fuses were centrifugal), side-pockets centrifugal fuses are an exception. They are a specific, original Bofors development.
I attach here the patent submitted by Bofors in the UK, dated 1939, this kind of fuze (it includes a very detailed description of their mode of action and detailed drawings - including for the nickel tool used to set these fuzes).
The design of these fuze impacted on the design of the whole bomb and is in fact the cause of the very peculiar characteristic look of the Swedish bombs:
The ring between the fins of Swedish designed bombs is not designed to be a "stabilizing" ring as in British, French and German bombs - here, stabilization during the fall is acquired through the spinning of the bomb. Its role is to insure that this spinning will indeed take place accurately by maintaining the correct original orientation of the fins on the longitudinal axis of the bomb
The fin deformation problem was the cause that led most countries to abandon the spinning stabilization in aerial bombs design - with very few exception, the most notable one being the Great Slam and Tall Boy bombs - but their fins were so massive that risk of deformation was not relevant in their case.
This is also the reason why this ring is a simple ring and not a funnel (no need for such a funnel here, only for a metal strengthening link, which design is in fact stronger than any funnel)
[FONT=&amp]Centralrör Drawing 1.jpgCentralrör Drawing 2.jpgCentralrör Drawing 3.jpgCentralrör Drawing 5.jpgCentralrör Drawing 6.jpgCentralrör Drawing 7.jpg


Centralrör 1.jpgCentralrör 2.jpgCentralrör 3.jpgCentralrör 4.jpgCentralrör 5.jpgCentralrör 6.gif
[/FONT]
A typical Swedish bomb / The tool for mounting & dismounting the fuze on the bomb / The tool to set the fuze

IMG_7829.jpg [FONT=&amp]Rörnyckel till centralrör i bomber 032wZ19itkMV.jpg [/FONT][FONT=&amp]916113_S_FV_object_FVM153132.jpg[/FONT]
 
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