Captive screw
Captive screws are called screws that have an additional protection against loss after loosening. Here, to the screw , after loosening of the screw connections remain captive in one of the associated components.
A distinction must be made between captive screws and lock nuts and screws that are equipped with a self-locking screw locking agent in order to prevent them from loosening by themselves.
Norms
In the case of machines that have fixed separating protective devices, these must be designed in accordance with the Machinery Directive 2006/42 / EC in order to meet the relevant requirements for CE marking: " After the protective devices have been removed, the fasteners must be attached to the protective device or to the machine stay connected ".
use
Based on the above standard, such screw connections are used on safety cladding of systems. Captive screws are used in many other places as well.
Use in consumer goods
E-ring on the battery compartment screw
Captive screw on a selfie stick
E-ring on the screw of a camera strap
Web links
Individual evidence
- ↑ Directive 2006/42 / EC (Machinery Directive) , adopted into German law on December 29, 2009. The directive regulates a uniform level of protection for accident prevention for machines when they are placed on the market within the European Economic Area (EEA) as well as Switzerland and Turkey. The former Machinery Directive 98/37 / EC is therefore no longer in force. Section relevant for this article: Annex I, Chapter 1.4.2.1 "Fixed guards"