La serie Elevation Line comprende sia freni monodisco a pressione di molle alimentati in corrente continua che freni a doppio disco a molla conformi alla normativa EN 81 (Regole di sicurezza per la costruzione e l'installazione di ascensori e montacarichi). I microinterruttori integrati permettono di conoscere lo stato del freno attraverso l'interrogazione remota (posizione dell'ancora, usura, cuscinetto dell'ancora). Grazie al nuovo concept di sicurezza brevettato non è necessario effettuare le prove sul sistema di frenatura a doppio circuito del freno a molle che altrimenti sarebbero obbligatorie all'atto del collaudo degli impianti di sollevamento. Questo freno risulta particolarmente adatto dove c'è l'esigenza di installare tutti i componenti dell'impianto come il motore, gli ingranaggi e il freno rispettando lunghezze ridotte. I prodotti della linea ELEVATION trovano impiego soprattutto nel settore degli ascensori, ma sono indicati anche per tutte le applicazioni che devono soddisfare rigorosi criteri di sicurezza. Nei freni elettromagnetici a molle la coppia frenante viene generata al disinserimento della corrente.
This text is only available in English
Spring-applied single-disc brakes in the 76 461..A00 series are electromagnetic components designed to operate dry. The armature system of the brakes is torsion-proof, friction-free and axially movable in tangential direction. The force generated by the electromagnetic field is used to neutralise the braking action caused by the spring force. Spring-applied single-disc brakes engage in unpowered condition and release when DC voltage is applied to the field coil of the brake. Spring-applied single-disc brakes do not exert any axial force on the shaft to be decelerated. The fixed hand release allows opening (releasing) of the brake manually (e.g. in the event of a power failure) to neutralise the braking action of the spring-applied brake. Built-in factory-set microswitches control the operating state of the brake and must be integrated into the control circuit of the machine (e.g. lift machine). Owing to the form-fit connection between the friction disc and hub of the spring-applied single-disc brake and the torsion-proof and axially fixed position of the hub on the shaft of the machine (e.g. lift machine), the friction disc is decelerated and the brake torque is transferred to the machine (e.g. lift machine) via the shaft when the brake is unpowered. The machine shaft is decelerated or held in position. The special structure of the armature system and microswitch monitoring system allow the user to identify the current operating state of the brake (released – engaged – worn out – armature system fault) and initiate corrective action. The armature system is friction-free thanks to the use of spring segments, so that the torsion-proof armature can be moved axially for torque transmission. Additional support elements (sleeves) are provided which support the armature system if and only if the segment spring fails, so that a reliable generation of the braking torque is ensured at all times. The built-in microswitch monitoring unit is designed to detect segment spring failure and to report such failure to the machine control system. Owing to the torsion-proof, friction-free and axially movable arrangement of the armature system and the built-in microswitch monitoring unit, the spring-applied single-disc brake can be used wherever short overall lengths of motor/brake combinations or motor/gearbox/brake systems are necessary and safety requirements for the construction and installation of lifts according to EN 81-1 must be met. According to the requirements specified in EN 81-1, the user must select a suitable braking system with adequate braking torque to ensure that the brake, if used in applications according to EN 81-1, is by itself able to adequately decelerate a lift car that is loaded with the 1.25-fold of its rated load and moves at rated speed. Type 76 461..A00 spring-applied single-disc brakes are mainly intended as holding brakes with emergency stop function to be used in lift machines with drive control inside buildings.
The magnet housing of the spring-applied single-disc brake accommodates the firmly fitted field coil with connecting cable (cable exit on the circumference of the magnet housing) and the compression springs which frictionally press the internally toothed friction disc against the friction plate via the studs and the armature and, thus, against the mounting surface (e.g. motor end shield of a lift machine). The friction disc can be moved axially on the hub. As a result, the M4 transferable torque is fully applied to the shaft of the machine (e.g. lift machine). The sleeves are tightly pressed into the magnet housing. Together with the armature and friction disc, they result in the air gap 's' of the spring-applied single-disc brake. The two microswitches included in the built-in monitoring unit control the operating state of the spring-applied single-disc brake. A segment spring connecting the armature to the magnet housing ensures that the armature is torsion-proof, friction-free and axially movable. Owing to the elastic deformation of the segment spring, the armature is able to move axially under the action of the electromagnetic field and the spring force of the compression springs. The braking torque acting on the armature through the friction disc in braking mode is transmitted via the segment spring to the magnet housing and further via the sleeves to the mounting surface of the machine (e.g. motor). The hub which is axially fixed to the shaft of the machine (e.g. lift machine) for coupling the friction disc is provided with a keyway to ensure that the braking torque is transmitted to the shaft via a feather key provided in the shaft. The O-ring inserted in the hub reduces the running noise produced by the friction disc of the spring-applied single-disc brake. The brake is fixed to the mounting surface of the machine (e.g. lift machine) by means of the mounting screws provided for this purpose. When using brakes with hand release, openings must be provided in the part enclosing the brake (e.g. fan cover) so that the hand release lever can be installed.