Coupler and vehicle with coupler

A coupler, comprising:

• a coupler body, having an accommodating cavity, wherein the coupler body is provided with a first impact protection pin flange;
• and
• a coupler tongue, pivotally connected with the coupler body, wherein the coupler tongue comprises a head portion and a tail portion, the tail portion is disposed inside the accommodating cavity, and a first interval d is formed between an end surface of the tail portion and the coupler body, wherein the coupler tongue further comprises a second impact protection pin flange, and a second interval b is formed between the first impact protection pin flange and the second impact protection pin flange, wherein the first interval d and the second interval b satisfy:
• d<b;
• wherein the coupler body is provided with a first impact platform, wherein the coupler tongue further comprises a second impact platform, and a third interval a is formed between the first impact platform and the second impact platform, wherein a<d.