Technogym New Bike EXCITE Plus, Техническое обслуживание руководство

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- New Bike: Technical service guide - rev. 4.1
Page 3.18
3.17. ELECTROMAGNETIC BRAKE
It is an eddy current Brake, consisting of a flywheel mass and a flat copper disk which turns in the
air gap of a winding. When there is a variation in the current to the winding, the field produced by it
also varies and there is a consequent variation in the eddy currents induced in the copper disk and
the resistance supplied to the movement of the pedals on the equipment.
Two solenoids (
Coils of a cylindrical shape consisting of a series of tight coils made with a single
thread of conducting material ) that are connected in line are provided with a power supply through
an adjustable direct current generator, so as to create a more or less intense magnetic field. The
inertia disk (flywheel) turns between the coils.
Due to the movement, each sector of the disk is crossed by a magnetic field flow that varies in
continuation and, as a consequence, electromotive forces are generated which cause the circulation
of induced currents. These currents have a direction that is opposite to the element that generated
them i.e. the movement of the disk inside the magnetic field itself. As a consequence a braking
effect is created which slows down the movement of the disk. The effect increases in intensity
according to the size of the magnetic field of the coils and the speed level of the disk. Due to this
operating principle, it is clear that when the disk is stationary, the braking effect is non-existent.
As opposed to the majority of mechanical brakes, which function by exploiting friction force, here
there are no parts subject to wear and tear.
The winding has a resistance of about 5Ω (Ohm), so, consequently, the brake absorbs a maximum
current of 2.2 A.
3.18. SPEED SENSOR
Only for models: POWERED.
It consists of a magnetic induction sensor which detects the heads of the screws that fix the disk of
the Electromagnetic Brake.
On self-powered equipment, the speed is measured by a built-in sensor on the generator (see
paragraph: 3.20. “Generator”).