Patents by Inventor Karin Ruth Johnson

Karin Ruth Johnson 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: 4082356
    Abstract: An educational puzzle chair for children between the ages of 18 months and 5 years of age. The chair includes two identical sides, a brace, two identical wedges, a back and a step. The chair is assembled by interlocking its parts in a predetermined manner and order without the use of any fastening elements or tools. All pieces except the sides are reversible. The components of the chair can be stored in a minimum amount of space and can be placed in a small container for easy carrying. The chair is durable and economical to produce.
    Type: Grant
    Filed: February 25, 1977
    Date of Patent: April 4, 1978
    Inventor: Karin Ruth Johnson