| 摘要 |
A drawing apparatus includes a base member of rectangular form with front, rear and opposite side margins and an upper surface with a compass rose plate for affixing a drawing sheet thereon and pivotally mounted to the base member upper surface. A carriage frame is positioned generally on the upper surface of the base member and has spaced guide members slidably mounted to the base member side margins and interconnected by a crossbar for coordinated translatory movement. A parallel rule structure is supported by the carriage frame and has first and second drawing bars and first and second links forming an expansible and contractible parallelogram generally positioned atop the compass rose plate. The links are respectively mounted to the spaced guide members of the carriage frame for sliding movement therewith over the compass rose plate and for positioning the parallelogram rule structure at selected locations thereon.
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