洗衣机上的“撞桶开关”该怎么翻译成英文呢？

首先，这个桶不是barrel而是basket
其次，这个开关叫bump switch

Adapted from wiki:
Many efforts have been made to counteract the shaking of unstable loads, first by mounting the spinning basket on a free-floating shock-absorbing frame to absorb minor imbalances, and a bump switch to detect severe movement and stop the machine so that the load can be manually redistributed.

Collision barrel switch

洗衣机上的“撞桶开关”就其功能来讲是保证洗衣机由于桶内衣服分布不均匀，在运转时动平衡失控而造成上下（滚筒式）或左右前后（普通式）与机壳体碰闯。所说的开关就是在动平衡失控时起作用的。我的意见可取名为“balance switch”或“anti-collision switch”，再有“balance controller/control switch”。上述仅供选择使用。

老外的机子上都是写的Bump switch