Roundness meter main components and measuring process

Classification of roundness machine

According to the condition of the workpiece during the measurement process, the roundness meter can be divided into two types: workpiece rotating type and workpiece stationary type.

The workpiece rotation type roundness tester is suitable for measuring relatively light and rotationally symmetrical workpieces, as well as measuring high shaft parts, such as machine tool spindles. The medium-sized roundness tester shown in the figure below is a workpiece rotary roundness tester.

The workpiece static roundness tester is suitable for measuring relatively heavy, non-rotationally symmetrical workpieces, such as engine blocks or cylinder heads. The large roundness tester shown in the figure below is the workpiece static roundness tester.

The main components of the roundness measurement equipment

1. Sensor

Convert tiny movements of sensors into electrical signals;

Usually with a mechanism to adjust the stylus angle and contact force;

The wobble of the stylus tip causes a change in inductance within the coil, which produces an electrical signal.

2. Stylus

contact with the surface to be measured;

The stylus head is usually spherical and polished;

There are ruby, sapphire, silicon nitride, tungsten carbide and other materials.

3. Spindle

There are several types: air flotation, hydrostatic, hydraulic and mechanical, etc.

Usually includes some form of angular position datum, and a method of determining the main axis angle from this datum.

4. Cross arm and column

The function of the cross arm and the column is to move the stylus to the measuring position;

Can be moved manually or automatically;

May have straightness measurement capability.

5. Pedestal

Active or passive anti-vibration devices are usually included to ensure the stability of the measurement results.

6. Electrical part

Includes data acquisition system, computer for data analysis and report generation.

Roundness testing machine measurement process

1. Adjust the attitude of the sensor and set the appropriate measurement force.

2. Adjust the axis of the workpiece to be tested to coincide with the spindle of the roundness meter as much as possible (alignment).

3. Touch the position to be measured (it may be necessary to adjust the attitude of the sensor again) to collect the raw data of the cylindrical surface or end surface.

4. Transfer the data to the PC software.

5. The software filters the raw data.

6. Fit the reference circle according to the requirements, and calculate the corresponding center position of the circle.

7. Calculate the corresponding parameter results according to different evaluation criteria.

8. Output results and reports.