Basic concepts of measuring instruments

- Aug 28, 2017-

The basic contents of the measuring instrument include: precision, error, measuring standard equipment, length measurement, angle measurement, shape measurement, traditional optical instrument. Application in precision measurement and so on.

The measuring instrument has contact test and optical test measure (now most used) Contact test: General measurement tools and 3D measuring tools (three coordinate measuring machine also called three times) three coordinate measuring machine is called three times, it can measure many complex space dimensions. such as molds and automotive products.

The three-coordinate measuring instrument is classified into three types, such as manual, motor drive and CNC, according to Operation mode.

Manual three-coordinate measuring instrument

The author holds the spindle with his hand to move it along the axis. When measuring, it is necessary to pay attention to measuring the pressure between the probe and the workpiece, and the movement of the probe caused by the acceleration of the shaft resulting in the measurement error.

Motor-driven three-coordinate measuring instrument

Motor-driven three-coordinate gauges are generally controlled by joystick. It has the advantages of high measurement accuracy, easy operation and guidance measurement.

CNC Type three coordinate measuring instrument

CNC Three-coordinate measuring instrument in addition to the motor-driven function, but also automatically according to the computer preset procedures for the implementation of measurement, and even some manufacturers produced three coordinate measuring instrument, also provides automatic loading and tear workpiece. The CNC three-coordinate measuring instrument can also be used to measure the profile (point-to-point measurement and scanning measurement) in addition to providing dimension measurement (point-to-point measurement).

Optical test measurement: can avoid the deformation of the product in contact test measurement and some contact test can not complete the work, the products are: two, three-dimensional laser copying machine and so on.

Two-dimensional also known as imaging instrument, image measuring instrument, two-dimension image measuring instrument, etc., is currently the major precision manufacturing industry geometric measurement is mainly used in measuring instruments. Includes manual image measuring instrument and automatic image measuring instrument.

Manual Image measuring instrument

Manual image measuring instrument relies on manual operation to control the movement of the X and Y axes of the measuring platform, to obtain the optical image of the object being measured, enlarge it through an optical microscope, and after the CCD camera system sends the magnified object image into the computer, it can efficiently detect the contour and surface shape size, angle and position of various complicated workpieces, and then read the required geometrical dimension.

Automatic Image measuring instrument

The automatic image measuring instrument is based on the manual image measuring instrument, which is changed manually to control the movement of X, Y and z axes of the computer system, which is more precise and convenient when selecting the geometry of the measured object's contour and angle. At present, it has become the most widely used image measuring instrument in China, and has the tendency of replacing manual image measuring instrument. Early measuring instruments