Counter nut意思

"Counter nut" is a term used in mechanical engineering and construction, particularly in the context of fasteners and hardware. It refers to a nut that is used to secure a bolt or screw from the opposite side of the material being fastened, providing a means to tighten or loosen the nut without the need for access to the entire length of the bolt or screw.

In other words, a counter nut is a nut that is used as a secondary fastener to prevent the primary nut from loosening due to vibration or other forces. It is typically used in applications where the primary nut is exposed to high levels of stress or where frequent adjustments may be necessary.

The term "counter" in this context means "on the opposite side" or "behind," indicating that the counter nut is installed on the opposite side of the material from where the bolt or screw is visible. This type of nut is often used in construction, automotive, and machinery applications where a secure and stable fastening is required.