The following 12 patents from Ihagee can be found at the site of the United States Patent Office. The complete text and all drawings are available as images. If you know more Ihagee patents, please let me know.
To get them on your screen, you need a special TIFF-format plug-in program. From www.alternatiff.com you can download a free plug-in. It works alright on my computer with Internet Explorer. Clicking on "Link" will bring you to the first page of each patent.
Patent 1611344 1926.12.21
From Hermann Hugo Frauenstein
Describes the Folding Reflex (Patent-Klapp-Reflex).
Link
Patent 2025609 1935.12.24
From Karl Nüchterlein
Describes the focal plane shutter of the VP Exakta (Standard-Exakta)
Link
Patent 2096856 1937.10.26
From Karl Nüchterlein
Describes the pre-war bulb flash for the VP Exakta
Link
Patent 2136148 1938.11.08
From Karl Nüchterlein
Describes the mechanism that prevents double exposures with the VP Exakta
Link
Patent 2136149 1938.11.08
From Karl Nüchterlein
Describes the bayonet mount of the Kine-Exakta
Link
Patent 2147106 1939.02.14
From Karl Nüchterlein
Describes the film pressure plate system of the Kine-Exakta
Link
Patent 2165903 1939.07.11
From Karl Nüchterlein
Describes the enlarging focusing glass of the Kine-Exakta
Link
Patent 2180064 1939.11.14
From Karl Nüchterlein
Describes the film transport + shutter setting mechanism of the Kine-Exakta
Link
Patent 2243160 1941.05.27
From Konrad Koehl
Describes the transparency projector Diaskop-Projektor
Link
Patent 2252513 1941.08.11
From Konrad Koehl
Describes the transparency projector Diaskop-Simplex
Link
Patent 2252640 1941.08.12
From Karl Nüchterlein
Describes a system for interchangeable view-finders for the Kine-Exakta
Link
Patent 2266656 1941.12.16
From Karl Nüchterlein
Describes the exposure counter mechanism of the Kine-Exakta
Link