Generally speaking, the common spring scale is made of spiral spring. After the measured object is put into the scale, the spiral spring is stretched under the gravity of the object to be measured. When stretching, the rack is driven to rotate by the gear pointer shaft through the lever device to make the rack move in a straight line. When the elastic force produced by the spring is in balance with the gravity of the object under test, the pointer indicates the weight value of the measured object on the dial.
The zero adjustable round spring scale is mainly composed of two compression springs, spring guide post, slide plate, transmission belt, belt pulley, zero adjusting button, etc. this scale uses pointer and disc scale to indicate the reading of weighing objects, so it is smaller in volume, smaller in scale, more intuitive in reading and convenient to carry. It also has the function of zero adjustment, that is, the pointer can be adjusted to zero after the first weighing, and then the weight can be weighed The device can read out the weight of the object to be weighed for the second time without the trouble of calculation