铸工车间在大件造型或合箱时,操作者都希望砂箱要尽量地缓慢下降,但一般天车吊钩的下降速度往往达不到理想的要求,经常会挤坏定位销,或是碰坏下箱里的芯子,给造型和合箱带来不少麻烦,也浪费很多时间。为了解决这个问题,我们把天车起落部分的电气线路作了很小的改动,达到了预期的效果。经过使用,证明非常稳妥、可靠,很受操作者的欢迎。现将改造后的线路图介绍如下: Casting shop in the large shape or fit the box, the operator wants the sandbox to slow down as much as possible, but in general the rate of decline of the crane hook often fail to meet the requirements, often squeeze the positioning pin, or touch Broken down the core of the box, to modeling and put together a lot of trouble, but also a waste of time. In order to solve this problem, we made a small change to the electrical circuit of the crane’s landing part to achieve the desired result. After use, proved very safe, reliable, very popular with the operator. The modified circuit diagram is as follows: