由于天平的刀盒结构不同,在调整偏差的过程中(因不加注意),对其它性能有不同的影响。以目前常见的刀盒为例,叙述如下。图1结构的刀盒,它是以七颗螺丝顶住刀子,使整个刀子悬于刀盒之中。此种结构在调整时,若能等量调整螺丝1、2和3、4,使刀子平行移动,将不会使其平行性产生明显的变化。不然,就会改变天平三刀刃的平行性, As the balance of the knife box structure is different, in the process of adjusting the deviation (due to lack of attention), have different effects on other properties. Take the common knife box as an example, described below. Figure 1 structure of the knife box, which is seven screws against the knife, so that the entire knife hanging in the knife box. This structure in the adjustment, if the same amount of adjustment screws 1,2 and 3,4, the knife parallel to move, will not make significant changes in parallelism. Otherwise, it will change the parallelism of the balance of three blades,