| 摘要 |
The invention comprises an adjustable magnifying device adapted for use on measuring instruments such as architectural, engineering or mechanical drafting scales. The device includes a vertical support member having a head, a spacing component and a shaft; a horizontal magnifying unit pivotally attached to the spacing component of the support member; and a receiving member spirally attached to the shaft of the support member. The receiving member includes a cylindrical indentation for spirally securing the shaft of the support member and a passageway of triangular cross section which receives and attaches to the top section of measuring instrument of triangular cross section. When the device is used in connection with relatively flat measuring instruments, an adapter of generally triangular cross section is received by and attaches to the receiving member of the device and also attaches to the upper surface of the measuring instrument. The magnifying device can be freely removed in the longitudinal direction while attached to the measuring instrument or the adapter. The magnifying unit may be pivoted to either side of the measuring instrument and adjusted vertically to allow for variations in the visual capabilities of persons using the device.
|
