Views: 0 Author: Site Editor Publish Time: 2022-10-31 Origin: Site
Weighing scales are also called "weighment ",Weighing apparatus. Or the weighing instruments with unequal arms are called scales, or refers to the lifting and tie bar scales that measure the weight of things by looking at the scales, or refers to the scale bars. During the Warring States period, there were unequal arm weighing apparatus. It has not been decided when the domestic steelyard started. The unearthed king of Chu bronze balance pole has a scale of ten equal parts. It is speculated that it is a sign of hanging weight and weight in different parts when weighing. It is likely to be a kind of weighing instrument in the transition from equal arm balance to pole scale. After the Eastern Han Dynasty, it evolved into a scale to see the weight from the scale star.
It is a small weighing instrument with wooden or metal rod with star point and taper as the main body, and equipped with mound (weight), mound rope and scale plate (or hook). According to the scope of use and the size of the scale, it can be divided into three kinds, i.e. chain, pan scale and hook scale. The steelyard is a first-class lever. It is a simple weighing instrument that uses the principle of lever balance to weigh. It is composed of a wooden steelyard with a steelyard star, a metal steelyard hammer and a lifting rope.
The steelyard scale consists of the first kind of lever, which focuses on the outer end of the fulcrum. When weighing, according to the weight of the object to be weighed, the weight and the weight rope move on the scale pole to maintain balance. According to the star point on the scale pole corresponding to the weight rope during balance, the mass indication of the weighed object can be read out. The structure and manufacturing process of the scale are simple, light and small, easy to carry and use, low cost, but low accuracy.
The steelyard scale is one of the most long-standing scales invented by human beings. Among the artifacts unearthed from the Chu tomb in the eastern suburb of Changsha, Hunan Province, China, there are various refined weights, scales, scales, silk threads and lifting ropes.
Among the relics unearthed from the Han Tombs in China 200 BC, there are various sizes of pole weights. In 1984, a complete wooden steelyard was found in a single kiln brick Tomb of Han Dynasty in Yaoshang village, Changxing Town, Meixian County, Shaanxi Province, China. It was made in the first century B.C. - A.D.
For a long time, the development of ancient steelyard was based on the use of rope knobs, non quantitative weights and wooden, bamboo and bone steelyards, which were made by hand. It was not until the 20th century that the traditional structure of rope button was gradually changed into the structure of outer knife button and knife bearing or inner knife button and knife bearing. After 1949, in order to strengthen the legal management of metrology, China has formulated the verification regulations and national standards of pole scales. From 1985 to 1987, China made a major reform on the structure of the pole scale, replacing the original wooden pole with metal pole, thus solving the problem that the accuracy of the measurement of the wooden pole is affected by the region and weather, and meeting the needs of semi mechanization, standardization, generalization and mass production. However, due to its low measurement accuracy, the steelyard scale has been gradually eliminated.
Lever type mechanical scale weighing 50kg to 1000kg. The load-bearing device is a small weighing instrument with rectangular table, which is usually used on the ground. According to the structure principle, it can be divided into mechanical platform scale and electronic platform scale.