1. Field of the Invention
The present invention relates to a measuring instrument. More specifically, the present invention relates to a measuring instrument including a display on which measurements are displayed.
2. Description of Related Art
A dial gauge is known as a measuring instrument for reading dimensions and the like of an object to be measured using a pointer and scales (see, for instance, Patent Literature 1: JP-A-2002-310601).
The dial gauge includes a spindle axially movable in a main body case and is configured to convert a displacement amount of the spindle to a rotary movement of the pointer via a magnification mechanism. The dimensions and the like of the object is measured by reading a rotation angle of the pointer from scales of a scale plate.
The scales are printed on an outer periphery of the scale plate at a predetermined interval. The scale interval is one factor for showing usability of the dial gauge. With a wide scale interval, the scales are easily read, whereas a stroke of the spindle per rotation of the pointer becomes short since the number of divisions in one round of the scale plate becomes small, thereby narrowing a measurement range. On the other hand, with a narrow scale interval, the measurement range can be enlarged since the stroke of the spindle becomes long per rotation of the pointer, whereas the scales are difficult to read.
Accordingly, in a typical dial gauge, an optimum scale interval is set in consideration of readability while ensuring a certain measurement range and is set entirely over the measurement range.
Since the optimum scale interval is set entirely over the measurement range in consideration of readability while ensuring a certain measurement range in a measuring instrument for reading dimensions of an object using the pointer and the scales as described above, disadvantages may occasionally occur.
For instance, for measuring a large variety of dimensions of a plurality of components, the measurement is possible since a relatively wide measurement range can be ensured. However, when the components have a small variety of dimensions and it is required to check whether or not the measurement value falls within a preset dimensional tolerance against the reference value, the scales are occasionally difficult to read within the range of the dimensional tolerance since the scale interval is set at an equal interval entirely over the measurement range.