Little information can be found about Rudi de Graff. The American Russian filed a patent in 1917 which was granted in 1921. Below is written down what he claims in his patent.
Rudi de Graff USSR Diving Armor 1917
1. In a metallic diving suit, a body member provided with a slot and a guide adjacent thereto and within said body member, an arc-shaped plate operable in said guide and engageable with the leg of the wearer at a point just above his knee, said plate having an aperture, and a leg member extended through said aperture.
2. In a metallic diving suit, a body mem her provided with a slot, and a guide adj a cent thereto and within said body member, anarc-shaped plate operable in said guide, said plate having an opening, and a leg member extended through said opening and engageable with the leg of the wearer at a point just above his knee, said leg member having lugs for the reception of a pivot for the leaves of a telescoping joint. 7
3. In a metallic diving suit, a body member provided with a slot, and a guide adjacent thereto and within said body portion, an arc-shaped plate operablein said guide, said plate having an opening and engageable with the leg of the wearer at a point just above his knee, and a leg member extended through said opening, combined with a plurality of leaves mounted on a pivot at the angle of said members, one of said leaves extended through said slot.
4. Ina metallic diving suit, a body member provided with a slot, and a guide adjacent thereto and within said body member,
anarc-shaped plate operable in said guide, said plate having an opening and engage able with the leg of the wearer just above his ‘knee, and a leg member extended through said opening, said leg member having lugs for the reception of a pivot for the leaves of a telescoping joint, said pivot being arranged in close proximity to said body member. i
5. In a metallic diving suit, a chest portion comprising side sections each a counterpart ofthe other andhaving radial semicircular fianges at their lower ends, a lower body portion having” an upward extension secured to said vflanges, said lower body portion comprising a cylindrical drum horizontally disposed with its axis lying transversely and having circumferential openings, a hollow upper leg portion U-shaped in horizontal section, a pin inclosed within the same at the rear, and a lower leg member mounted on said pin, and intermediate series of U-shapedsegments mounted on said pin and telescopically movable withineach other “and the saidupper legportion.
Signed at New York city, in the city, county and State of New York this 28th day of Dec. 1917. V a
RUDI De GRAFF.
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