物理天平的使用过程中,常会出现横梁跌落的现象,致使指针弯曲,影响仪器的准确度。严重时甚至会使横梁损坏,为了保护横梁不使指针弯曲、受损,我们对天平进行了适当的改进,试用后情况良好。我们的方法是:用1～1.5毫米厚的铝片做两只如图1所示的小钩,装在天平支柱上方两面支持横梁的尖头螺钉的下端,先取下下端螺母,装上铝片,再旋紧螺母,使有凹口的一面向外,然后在两钩之间套上一根橡筋(见图2)。这样装置后,既不影响天平的使用,又能防止横梁跌落,万一横梁受震落下,就 Physical balance of the use of the process, often the phenomenon of falling beams, resulting in pointer bending, affecting the accuracy of the instrument. In severe cases, even the beams will be damaged. In order to protect the beams from bending and damage of the pointer, we have made appropriate improvements to the balance and have done well after the trial. Our method is: with 1 ~ 1.5 mm thick aluminum sheet to make two small hooks as shown in Figure 1, mounted on the top of the balance pillar on both sides of the crosshead support the underside of the pointed screws, first remove the lower nut, fitted with aluminum , Tighten the nut so that the notched side is facing outward, then place a rubber band between the two hooks (see Figure 2). This device, it does not affect the use of the balance, but also to prevent the beams fall, if the beams fall under the earthquake