Techdrives is introducing the Mönninghoff M1 bi-stable electromagnetic tooth clutch that is engaged by applying a pulse of DC current and will only disengage when a second pulse is applied. This gives two significant advantages: first, it saves energy because the engaged clutch requires no applied current, which is particularly useful for batter-powered equipment; and, second, it offers increased safety, meeting the requirements of EU Machinery Directive 2006/42/EC clause 1.2.6 that refers to machinery where the drive must not disengage in case of a power failure. The M1 fulfils this criteria in that clutch cannot be released until a further pulse of DC current is applied.
Mönninghoff's patented M1 design adds an extra pair of toothed rings mounted internally, one ring having alternate shallow and deep teeth. Coil springs press these together until an applied DC pulse to the clutch coil causes them to open and index round by one tooth. After the pulse the teeth re-engage, and indexing from a shallow to a deep tooth allows the main tooth rings that transmit the torque to engage. Similarly, the next pulse indexes to the shallow tooth that holds the main tooth rings open.
This M1 bi-stable clutch will be launched at the Hannover Fair in April 2013. A range of four sizes suits torque from 50 to 500Nm and shaft diameters 20 to 50mm. Clutch engagement can be made statically or at low speeds, whereas dis-engagement is possible at any speed. The M1 bi-stable clutch is available in the UK via www.techdrives.co.uk.