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Manufacturers Index - Hugo Bilgram, Bilgram Machine Works

Hugo Bilgram, Bilgram Machine Works
Philadelphia, PA, U.S.A.
Manufacturer Class: Metal Working Machinery

Patents
This page contains information on patents issued to this manufacturer.

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USPTO = U.S. Patent Office . Images of the actual patent can be viewed on the U.S. Patent Office web site but a special TIFF viewer must be installed with your browser in order properly work. More information on how to configure your computer to view these patents can be found at TIFF image Viewers for Patent Images.
DATAMP = Directory of American Tool And Machinery Patents . A sister site to VintageMachinery.org with information on patents related to machinery and tools. A much easier user interface than the USPTO's for finding information on machinery patents.

Patent Number Date Title Name City Description
133,192 Nov. 19, 1872 Improvement in steam-engine governors Hugo Bilgram Philadelphia, PA
158,669 Jan. 12, 1875 Improvement in cut-off valve-gears Hugo Bilgram Philadelphia, PA
164,132 Jun. 08, 1875 Improvement in cut-off-valve gears Hugo Bilgram Philadelphia, PA
289,607 Dec. 04, 1883 Metal-planer Hugo Bilgram Philadelphia, PA
294,844 Mar. 11, 1884 Bevel-gear cutter Hugo Bilgram Philadelphia, PA
455,787 Jul. 14, 1891 Balance-wheel for time-pieces Hugo Bilgram Philadelphia, PA
506,412 Oct. 10, 1893 Cigarette-machine Hugo Bilgram Philadelphia, PA We're not sure why this inventor, known for his gear-making machinery, designed a machine for making cigarettes. The machine must have been successful as it was also patented in England, Brazil, Spain, and Mexico.
508,196 Nov. 07, 1893 Machine for grinding the edges of spectacle or eyeglass lenses Hugo Bilgram Philadelphia, PA
    Machine for grinding the edges of spectacle or eyeglass lenses Thomas A. Willson Reading, PA  
565,851 Aug. 11, 1896 Cigarette-machine Hugo Bilgram Philadelphia, PA
572,150 Dec. 01, 1896 Cigarette-machine Hugo Bilgram Philadelphia, PA
634,102 Oct. 03, 1899 Paper-bag machine Hugo Bilgram Philadelphia, PA
655,668 Aug. 07, 1900 Mechanism for feeding sheets of paper, &c. Hugo Bilgram Philadelphia, PA
    Mechanism for feeding sheets of paper, &c. Oscar L. Schehl Philadelphia, PA  
656,340 Aug. 21, 1900 Bag-machine Hugo Bilgram Philadelphia, PA
665,054 Jan. 01, 1901 Gear-cutting machine Hugo Bilgram Philadelphia, PA
749,683 Jan. 12, 1904 Process of shaping gear-teeth Hugo Bilgram Philadelphia, PA Robert S. Woodbury's 1958 monograph, "History of the Gear-Cutting Machine", identifies this Bilgram patent as an especially important one in the history of gear cutting. At the time of this patent, the automobile industry was motivating much work in improving machine tools. The challenge with gear design was that theoretically perfect gear teeth could be noisy in practice. This patent specification notes that existing gear-tooth designs have the force transmitting either evenly through two teeth or entirely by one tooth, alternating between the two states as the gears rotate. Bilgram's idea was a new tooth shape where a tooth gradually assumes a larger share of the force as the gears rotate, this force then gradually decreasing as the next gear-tooth engages. A separate patent covered an additional improvement that slightly relieved the points and bases of the teeth to allow for misalignment due to bearing play and shaft flex. Both of these patents are improvements to the inventor's earlier patents 294,844 and 656,166.
749,606 Jan. 12, 1904 Gear-cutting machine Hugo Bilgram Philadelphia, PA This gear cutting machine is designed to cut a tooth profile that varies slightly from the "ideal" mathematically determined profile so that the load on a tooth gradually increased to a maximum and then falls off as the next tooth comes into engagement. This avoids the humming noise that comes from the ideal tooth where the load is shared equally across two teeth and until one of them falls out of engagement and then the entire load is suddenly transferred to the other tooth.
955,113 Apr. 12, 1910 Continuous-cigarette-cutting machine Hugo Bilgram Philadelphia, PA
RE13,502 Dec. 31, 1912 Gear-cutting machine Hugo Bilgram Philadelphia, PA
1,187,295 Jun. 13, 1916 Stamp applying and affixing machine Carl Feddern Philadelphia, PA This machine is for applying revenue stamps to tobacco cans.
    Stamp applying and affixing machine Hugo Bilgram Philadelphia, PA  
    Stamp applying and affixing machine Louis Fischer Philadelphia, PA  
1,251,466 Jan. 01, 1918 Automatic braking device for compensation-gears of automobiles and other similar vehicles Hugo Bilgram Philadelphia, PA
1,277,837 Sep. 03, 1918 Automatic braking device for compensation-gears of automobiles and other similar vehicles Hugo Bilgram Philadelphia, PA
1,798,059 Mar. 24, 1931 Machine for making rotors Hugo Bilgram Philadelphia, PA
    Machine for making rotors Myron F. Hill Bridgeport, CT