Perspective drafting apparatus
US4918822A · kind A · utility
Inventor
Key dates
| Filing date | May 15, 1989 |
| Grant date | Apr 24, 1990 |
| Priority date | — |
| Expiry date | May 15, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB43L13/141
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
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 …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.