New electronic braking torque regulation for ROBA-stop? safety brakes

The new, intelligent braking torque control module by mayr? power transmission makes it possible to decelerate devices and machines evenly and gently. This innovative and economically attractive solution is pre-destined for application in smart, interconnected machines.

Nobody would even think of using the handbrake or parking brake when a car is going at full speed. In order to decelerate the car as required, a driver would use the foot brake. Gradual, even deceleration is also often desired for devices and machine applications with dynamic braking actions. However, as safety brakes - in contrast to car brakes - can only distinguish between two operating conditions due to their design, namely "braking torque present" and "no braking torque present", every braking procedure is carried out with the maximum braking torque available. With the new, intelligent braking torque control module, mayr power transmission offer an economically attractive solution to generate a variable braking torque for ROBA-stop safety brakes, making it possible to decelerate machines evenly and gently.

Continuous braking torque changes when in operation

Up to now, brakes have been dimensioned with regard to the maximum load where devices with variable loads, for example forklift trucks, are concerned. However, it is not always expedient to work with the full braking torque. In case of partial loads, a stronger deceleration than necessary can lead to damage to the transported goods or even to sliding of the wheels. If, however, the system detects the operating conditions and converts this information into a default signal for the new, intelligent control module by mayr power transmission, electronic braking torque regulation is possible. Using the new system, the brake specialists have succeeded in continuously changing the contact force on the brake linings and therefore also the braking torque during operation. In this way, machines can be decelerated gently, adapted to the respective system requirements. Furthermore, the new braking torque regulation makes it possible to compensate for negative influences on the braking torque consistency in applications requiring a constant braking torque within narrow tolerance limits.

Prerequisites for a smart machine

The new, intelligent switching device by mayr? power transmission, which is operated with 24V or 48V DC voltage, can control brakes with a coil nominal current of 10A or 5A. In addition, the resulting clamping force for the brake rotor can be specified to 25%, 50% or 75% of the nominal spring force by means of two digital inputs. Alternatively, a continuous, analogue default signal from 0 to 10V is possible. The switching device determines without using a sensor whether the armature disk is attracted or has dropped. This makes it possible to adjust the overexcitation time automatically as desired. Due to the fact that the intelligent switching device registers the switching condition of the brake, no microswitches or proximity sensors including the respective cabling are necessary as would normally be the case. The device also takes possible wear reserves into account, and, if required, recognises unpermitted high temperatures. With its compact dimensions of 30 mm in height, 69 mm in width and 103 mm in length, it can easily be integrated into control cabinets.

With the new braking torque control module, mayr power transmission provides the possibility to build up control circuits and brake movements intelligently - ideal prerequisites for application in the smart, interconnected machines of the future.

Bestle Hermann, Chr. Mayr GmbH + Co. KG, Germany. Email: hermann.bestle@mayr.de