Classification of Probe

Faced with a wide variety of probes on the market, how should we choose the one that best suits our needs? Is there a full-featured probe that can meet different requirements for measurement? We believe that all customers in the machining field have encountered such problems. Today we will discuss the characteristics and differences of different types of probes, and will give some suggestions for probe selection from the user's perspective. Hope it can be helpful to you.

1. Touch trigger probe

Touch trigger probe: it is also known as switch probe, which is the most basic and most commonly used type of probe for measuring machines. The main task of touch trigger probe is to send out a latch signal when the part is detected, and to latch the three-dimensional coordinate value of the coordinate point of the measured surface in real time. Touch trigger probes are divided into three types according to their working principles: mechanical switch probes, strain gauge switch probes and piezoelectric ceramic switch probes.

2. Continuous scanning probe

Scanning Probe: it is also known as proportional probe or analog probe. This kind of probe can not only be used as a touch trigger probe, but more importantly, it can output a signal (analog voltage or digital signal) proportional to the deflection of the measuring bar. The three-dimensional coordinate signals of the computer and the measuring machine can be read in at the same time to obtain the three-dimensional coordinates of the detected point. This kind of probe has a high sampling rate during scanning, and the measurement of discrete points can determine the normal direction of the surface where the point is located, so it is more suitable for surface measurement.

3. Laser probe

The principle of the laser probe is simple optical triangulation ranging, and the semiconductor laser and CCD detector are its key components. When the measuring machine moves continuously, a scan line will be obtained. Considering practical application problems, such as possible light blocking of the step surface on the part, there are different solutions for the design of the internal light path. In this simple principle, if the light source is changed to a line laser, and the CCD is changed to an area array, a line scanning laser probe will be produced, that is, a scanning band will be obtained when the measuring machine moves continuously.

4. Optical video probe

The optical video probe, or vision probe is actually a CCD camera. The surface of the part is imaged by the camera, and then the data image analysis technology is used to extract the measurement elements. This kind of probe is often accompanied by an illuminating light source to ensure sufficient imaging brightness. The main application field of optical video probe is the measurement of two-dimensional parts. It is the standard probe of tool microscope and two-coordinate CNC measuring machine. When used on the coordinate measuring machine, it can be an additional function to realize the task of non-contact two-coordinate measurement.