Patent DE-1905-175477

Here is another patent on which the Patent Object on the Lilienthal website gives “Hofmann, Josef”, though the original only shows “J Hofmann”.

The title of the patent itself is simply “Schraubenpropeller”. The national tech classification which we would call DE 77h.6 is consistently printed on the original document. However, “Klasse 62c Gruppe 1” is pencilled in. This sort of thing happens on a few of Hofmann's German patent.

Patent family descending from Patent DE-1902-141656

• Patent DE-1902-141656 (English title: screw propeller, National tech categories: DE 65a)
• Patent DE-1905-175477 (English title: Improvement of screw propellers, Supplementary to patent: Patent DE-1902-141656, National tech categories: DE 77h.6 • DE 62c.1)

Sources

• Patent Objekt via Lilienthal museum patents
• Patent Digitalisat via Lilienthal museum patents
• Inventor location: Berlin
• Original patent document and Bibliographic info at DPMA
• Original patent document and bibliography entry at espacenet

Year filed	1905
Year granted	1906
Office	DE
Patent number	175477
Inventors	Joseph Hofmann
Inventor country	DE
Applicant person	Joseph Hofmann
Applicant firm
Applicant type	INDIV
Applicant is inventor?	1
Original title	Verbesserung der Schraubenpropeller
English title	Improvement of screw propellers
Tech fields	Propellers, Propulsion, Airplane
Filing date	1905-06-05
Full specification filed date
Application number
Grant date	1906/09/29
Granted?	1
Publication date	1906/09/29
Supplementary to patent	Patent DE-1902-141656
Related to aircraft?	1
Serial number
Patent agent
Assigned to
National tech categories	DE 77h.6, DE 62c.1
IPCs	IPC B64C11/00
CPCs	CPC B64C11/006
Family year	1902
First filing?	0
Cites these patents
Citations from after 1930
Application ID
INPADOC family ID
Number of text pages	2
Number of diagram pages	1
Number of figures	3
Number of claims	1