mitutoyo 501s 用户手册

 

 

DESIGNING THE FIXTURES 

 

This chapter describes precautions to be observed when attaching 
the emission unit and the reception unit, which have been detached 
from the support base of the measuring unit, to a specially arranged 
dedicated fixture. 

 

 

 

 
In application, the emission unit and the reception unit may have to be detached from the 

support base of the measuring unit and attached to a dedicated fixture. If this is the case, 
the measuring accuracy cannot be ensured unless the emission unit and the reception unit 
are properly aligned on the dedicated fixture. Design a proper fixture according to this 
section. 

 

 
To ensure accurate measurements, design the fixture so that the workpiece to be 

measured can be positioned at the point of measurement that is the focal point of the 
emission unit. Also, make allowances for calibration and for a calibration gage to be 
mounted on the fixture. 

 

As shown in the figure below, the scanning beam of the measuring unit is produced by 

reducing the thick beam to a beam of the minimum diameter at the measuring position that 
is the focal point. 

However, since the inclination of the reception signal is defined as “beam 

diameter/scanning speed”, the inclination will be the steepest at measuring point (b) and will 
be less steep at points (a) and (c), off from the measuring point. 

The less steep the inclination of the reception signal, the more susceptible the signal is to 

noise and light disturbance, resulting in degraded repeatability. Thus, due attention should 
be paid to ensure that the workpiece is located at the measuring position. 

 
 
 
 
 
 
 
 
 
 
 

Measuring position that is focal point. 

Inclination of the reception 

Measuring region

Emission unit side

（ａ）          （ｂ）      （ｃ）

Reception unit side