摘要 |
An automatic drafting device has a carriage with toothed wheels in meshed engagement with toothed racks extending across a planar support surface. A pressure regulation device is mounted on the carriage and regulates the pressure applied to a stylus holder held by the device. The stylus holder containing a writing instrument can be lifted and lowered by a direct current motor with an eccentric disc. The writing tip of the instrument held in the stylus holder, when not in use, is supported on a soft resilient material, such as rubber, to form a seal preventing air from reaching the tip. When the writing instrument is lifted off the resilient material it is ready to write. |