How to choose the right ball diameter coordinate measuring needle

The CMM measuring needle is a part of the measuring head system of CMM, which is mainly used to touch the workpiece surface, generate signal trigger and collect measurement data through the displacement of the measuring head mechanical device. Ruby measuring needles are now widely used on the market.

For contact detection, choosing the correct coordinate needle can ensure the accuracy and efficiency of measurement.

For the measuring needle, the large measuring ball should be selected as far as possible when selecting the three-coordinate measuring needle.

The measuring needle of large measuring ball can increase the distance from large diameter to the surface of measuring needle rod and reduce the probability of false trigger caused by collision of measuring needle.

Because the surface finish of the measured workpiece directly affects the accuracy of CMM measurement results,

Therefore, in the CMM, the larger the diameter of the measuring needle and the measuring ball, the lower the requirements for the surface finish of the measuring workpiece.

Zeiss Needle measuring accessories general knowledge

I. Thread specifications

Accessories such as measuring pins or extension rods are known to be tightened with threads. Therefore, in the selection of accessories for use, it is necessary to understand the thread specifications of the accessories supported by the current equipment.

The size of the thread depends on the type of sensor selected by the device. Take Zeiss equipment, for example.

1. Equipped with VASTXTGOLD or VASTGOLD probes (active probes)

Accessory thread selection is the most flexible, the default thread size :M5(for measuring needle, you can also choose M2 or M3 specifications according to the actual situation, just purchase M2-M5 and M3-M5 adapters separately)

2. Equipped with VASTXXT or VASTXDT probes (passive probes)

Default thread size: M(3) can also choose the M2 size according to the actual situation, just buy another M2-M3 adapter)

3. Equipped with RENISHAW probe (TP20/TP200 etc.)

Default thread size: M2

II. Materials

Different spare parts use different materials. The different materials correspond directly to the weight, stiffness, durability and price of the accessories. In general,

1. With the VASTXTGOLD or VASTGOLD probe (active probe) attachment

With the most available types, steel, aluminum alloy, titanium alloy, THERMFOIT, ceramic (needle measuring rod) can be selected

Ruby, silicon nitride, diamond, ceramic (large diameter measuring needle, more than 15mm), steel (custom measuring needle or large diameter measuring needle), etc