General description

・This lecture introduces the precision positioning fixture installed on the microscope table, making the setup changes easier during precision positioning on the microscope.
Setup changes on the microscope used for high precision positioning can be made easy by standardizing the base plate of the precision positioning fixture and designing a parallel adjustment mechanism to be installed at three locations on this base plate.

Explanation

・Some devices use a microscope for precise positioning of two components. (Fig.1)
・For tasks involving setup changes, it is difficult to adjust the perpendicularity between the microscope's optical axis and the precision positioning fixture.
・One of the methods to shorten the time required for high-precision positioning is to install the precision positioning fixture on the microscope table in order to make the setup changes easier.
・The precision positioning fixture installed on the microscope table must have the following characteristics in its structure:

・Fig.2 is the structural image of the item 1.
a) Prepare the precision screw adjustment mechanisms at three locations in the outer circumference of the precision positioning fixture (Fig.3)
b) Assemble (attach) the steel ball while ensuring the coaxial accuracy of the tip of the precision screw adjustment unit
c) Design the fastening structure where the precision adjustment screw is attached so as to set the screw unit in place

・In the microscope table area facing where the three precision adjustment screws are mounted, prepare a nest for securing a steel ball located on the back of the precision screw adjustment mechanism (Fig.2 and Fig.4)
・The considerate design of the three steel ball nests on the microscope table leads to excellent repeatability of the installation positions for the precision positioning fixture. (Fig.4)
・The steel ball nest comes in a set of cone, groove, and flat type models. Using these three types as one set prevents a backlash of the three steel balls during positioning.

Precautions

・The fixture's setup position can be accurately repeated by the precision screw positioning mechanism and the steel ball nests on the microscope table. However, for more precise positioning, it is recommended to adjust the cursor line of the microscope in relative to the fixture after its replacement.