tripod for tacheometer

Structure of mechanism
Function	This device is a tripod. It has three wooden legs, each featuring a metal point at its extremity. When used with wedges on the lower outside part of each leg, this seats and stabilises the tripod on soft ground. A screw at the top of each leg is used to fix its orientation. At the top end there is a metal disc, called a flange, and a screw enabling the topographic apparatus to be attached. A spherical spirit level located on the flange is used to set the horizontal level of the tripod. Underneath the flange there is a rod with a spring and a screw. At the lower end of the rod there is a hook for attaching a plumb line. A ring with two wings enables the screw to be turned to attach the apparatus. A mechanical system allows the flange and the rod to move relative to the three legs. The tripod is used as a support for a topographic device, which can be a builder’s level, an aligning circle, a theodolite or a tacheometer. The flange must be in the horizontal plane, which is verified by a spirit level. The point where the tripod must be positioned for the measurement is materialised by a marker, which is a metal disc attached to a rod. For the device to be exactly vertical with respect to the parker, a plumb line is suspended from a hook below the tube, and must hang exactly above the marker. If the tripod cannot be moved, a mechanical system enables the flange to pivot to fine-tune the position above the marker.

Guidance function
Trace of a dedicated point on follower	Open trace
Dimension of mechanism	spatial

Permanent links

DMG-Lib		https://www.dmg-lib.org/dmglib/handler?mcdsc=3040025
Europeana		http://www.europeana.eu/portal/record/2020801/dmglib_handler_mcdsc_3040025.html