目前,国内使用的小模数双啮仪中,有一部分是瑞士进口的0 R、1 R、2 R三种型号,在早期进口的这类仪器中,记录电箱的记录笔都是热笔,其结构如图1所示。当记录电箱通电后,电阻丝4使记录笔尖6产生热量,便在电热纸上画出误差曲线,在使用中由于量程大等原因,有时使笔尖折断, At present, some of the small modulus nippers used in China are partly imported from Switzerland. They are 0 R, 1 R, 2 R. In the earlier imported instruments of this kind, the recording pens were all hot pen , The structure shown in Figure 1. When the recording box is energized, the resistance wire 4 causes the tip of the recording pen 6 to generate heat and draws an error curve on the heating paper. Due to the large measuring range and the like, the tip sometimes breaks,