Techdrives has created a page on its website that provides advice and guidance on specifying spring-applied brakes (sometimes also known as normally-on brakes or failsafe brakes). These brakes are usually electromechanical devices that remain 'off' so long as a DC current is applied; removing the current causes the brakes to be applied and remain on until the current is restored. Applications range from cranes and hoists to gates, escalators and vehicles for the disabled.
The new article, How to select your spring applied brake, explains the basics of spring-applied brakes and describes, with the aid of a clear diagram, how they are constructed and how they operate.
To help engineers specify spring-applied brakes, the article discusses braking torques, limiting speeds and friction energy. It also covers operating conditions and the important subject of lifetime and wear.
In relation to safety-critical applications, the article states that 'spring applied brakes are not truly failsafe although they are highly dependable'. It then goes on to suggest a suitable service factor and tells readers where they can obtain B10 and B10d values (as required for safety evaluations to EN ISO 13849-1) for the Intorq brakes supplied by Techdrives.
Another important topic covered by the article is brake switching, and finally the article presents some of the many options that can be specified for spring-applied brakes, such as manual release, sealing, mountings, wear indicators and double brakes.
Follow the link to read the full article about How to specify spring-applied brakes.