Patents by Inventor Melvin Marmer

Melvin Marmer has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4114294
    Abstract: An arithmetic teaching device which includes a calculator for performing arithmetic problems, such as addition, subtraction, multiplication and division, a display means having a first display portion and a second display portion with the second display portion which provides indicia of the answer having a delay means connected thereto such that from the keyboard the student may provide a visual display of the numerals and the operatives, such as a plus or minus symbol, on a display face and mentally provide an answer to the problem before a second display portion displays the answer. The timing for display of the answer itself is adjustable to provide a variable delay time. The device allows the student sufficient time to mentally form an answer which then when subsequently displayed can be compared with the proper answer provided by the device.
    Type: Grant
    Filed: April 7, 1975
    Date of Patent: September 19, 1978
    Inventor: Melvin Marmer