Are the weighing beam and the weighing beam correct?

The weighing beam and the weighing beam are correct. The weighing beam is also called the steelyard, the wooden pole of the steelyard and the component of the steelyard.

The steelyard is a kind of scale, and it is a simple weighing instrument that uses the lever principle to weigh the mass. It consists of a wooden weighing beam with a weighing star, a metal weighing hammer and a knob.

principle

The steelyard consists of the first lever, and its center of gravity is at the outer end of the fulcrum. When weighing, according to the weight of the weighed object, move the weight and the weighting rope on the balance beam to keep the balance. According to the star point on the balance beam corresponding to the counterweight rope during balance, the quality indication value of the weighed object can be read out. The accurate scale must meet the weight × scale spacing+0 kg for every increase of 65438 = the distance between the lifting button and the hanging point of the scale plate.

The scale is light in structure and working sequence, easy to carry and use, low in cost, but low in accuracy. According to Chinese national standards, maximum permissible error is 10% of the full scale.

Development history

The steelyard is the oldest weighing instrument invented by human beings. There are various refined weights, scales, scales, silk threads, hanging ropes, etc. among the cultural relics unearthed from the Chu Tomb in the eastern suburb of Changsha, Hunan, China before 700 BC. Among the cultural relics unearthed from the Han tombs in China before 200 BC, there have been various specifications of pole weights.

1989, a complete relic of wooden pole scale was found in a brick tomb of Han Dynasty in Yaoshang Village, Changxing Town, Meixian County, Shaanxi Province, China, and it was made about BC 1 ~ AD 1 century. The development of ancient steelyard has long been based on the use of rope buckles, non-quantitative weights and wooden, bamboo and bone scales. It was not until the 20th century that the steelyard gradually changed from the traditional rope buckle structure to the outer knife buckle plus knife bearing structure or the inner knife buckle plus knife bearing structure.

After 1949, in order to strengthen the legal management of measurement, China has formulated the verification procedures and national standards for steelyard. From 1985 to 1987, the structure of steelyard in China has been greatly reformed, and the original wooden pole has been changed into metal pole, which has solved the shortcoming that the measurement accuracy of wooden pole is affected by the region and weather, and met the needs of semi-mechanization, standardization, generalization and mass production. However, the steelyard has been gradually eliminated because of its low measurement accuracy.

Refer to the above? Baidu Encyclopedia-Scale, Baidu Encyclopedia-Scale