Portable teaching aid
Description
FIG. 1 is a front perspective view of a portable teaching aid showing my new design in operating open or expanded position;
FIG. 2 is a side elevation view thereof;
FIG. 3 is a top plan view thereof;
FIG. 4 is a view in elevation of the opposite side of FIG. 1; and
FIG. 5 is a perspective view of the teaching aid in closed position.
Referenced Cited
U.S. Patent Documents
Foreign Patent Documents
3345760 | October 1967 | Myhr |
60727 | March 1943 | DK |
458623 | July 1950 | IT |
Patent History
Patent number: D252758
Type: Grant
Filed: May 2, 1977
Date of Patent: Aug 28, 1979
Inventor: Lester E. Prall (Salt Lake City, UT)
Primary Examiner: Melvin B. Feifer
Attorney: W. Britton Moore
Application Number: 5/793,162
Type: Grant
Filed: May 2, 1977
Date of Patent: Aug 28, 1979
Inventor: Lester E. Prall (Salt Lake City, UT)
Primary Examiner: Melvin B. Feifer
Attorney: W. Britton Moore
Application Number: 5/793,162
Classifications
Current U.S. Class:
Demonstrator Or Exhibitor (10) (D19/62);
Writing Or Drawing Surface, E.g., Blackboard, Drawing Board, Etc. (7) (D19/52)
International Classification: D1907;
International Classification: D1907;