"自动敲钉机" can be translated as "Automatic Nailing Machine" or "Automatic Nail Driver".
Automatic Nailing Machine is a more general and commonly used term in industrial contexts, referring to a machine that automatically drives nails into materials.
Automatic Nail Driver is a more specific term that emphasizes the function of driving nails, and it is also widely understood.
Both translations are accurate, and the choice between them may depend on the specific context or the preference of the speaker.