As the inverter for weighing detection, the converter is usually a mechanical type, a contact switch type, a proximity switch type, or a photoelectric type. As for the pneumatic type, it is used very little.
1. Mechanical mechanical converters are generally used for mechanical weighing devices. When the balance position is reached, the scale valve is automatically opened by the stopper to discharge. 5〜1毫米。 The positional accuracy of this converter is generally about 0. 5~1mm.
2. The contact switch type contact switch has more than one pair of normally open and normally closed contacts. After the switch is activated, the metering control is performed by changing the conduction loop. The positional accuracy of the contact switch can reach about 0.1mm. To further improve its accuracy, an appropriate lever amplification mechanism can be configured. However, this will lengthen the action time. Conversely, if the accuracy requirements are not high and the action time is required to be short, then an appropriate lever reduction mechanism can be configured.
So far, the contact switch is still in use, and since the movable element is easily worn, the contact is easily burned, especially in a harsh environment such as oil, water, and dust, which is more prone to malfunction, thus limiting it. The scope of use.
3. Non-contact switch type The contactless travel switch developed in recent years has no movable components, the structure is simple, the probe is completely enclosed, and the service life is long. It is suitable for working in a harsh environment with high positional accuracy (about 0.03mm) ), the action range is wide, easy to adjust (about 5~25mm), the output pulse signal can be combined with logic circuit, and it is widely used.
4. Photoelectric type In the measurement, the photoelectric two-tube or three-tube is commonly used as the photoelectric converter. The photoelectric converter has no moving parts, and has a fast response speed, a positional accuracy of about 1 mm, a detection length of up to 10 m, and a wide use.