The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 24, 1990
Filed:
May. 15, 1989
Semond Levitt, Huntingdon Valley, PA (US);
Other;
Abstract
A perspective drafting device including a pair of straight edges pivotally connected to a centerpiece removably fixable to the horizontal arm of a drafting machine in place of the horizontal scale. Each of the straight edges is slidable through a vanishing point guide which latter is provided with a pin on its bottom surface extending substantially orthogonally to the drafting table and projectable downwardly for pivotal seating movement within a selected one of a number of holes provided in the surface of the drafting board at the left and right margins in rows spaced vertically along the drafting board. The vertical spacing of the holes selects the particular horizon desired, whereas the horizontal spacing of the holes provides horizontal rotation of the perspective view as desired. The centerpiece of the perspective device to which the straight edges are affixed is provided with a hole through which a vertical pin extending upward from the bottom edge of the table may be disposed, such hole being positioned in the centerpiece so that the center of the hole is in vertical alignment with the left-hand and/or right-hand edges of the vertical scale of the drafting machine. When the hole in the centerpiece is projected onto the fixed pin, the pin acts as a pivot so that movement of the drafting machine control knob permits pivoting rotation of the vertical scale to the left and to the right so that lines may be established from significant parts of the drawing from which it is desired to make the perspective view.