A bottle-capping machine has a rotor rotatable about a substantially stationary horizontal axis and having radially oppositely outwardly directed arms each having an outer end formed as a seat adapted to hold one of the caps. The processing nodes include at least one set of lock acquisition, system resource access and lock release nodes interconnected in a flow path. In using the heat dissipation device, after a value of rotation speed of the cooling fan has been determined by the rotation-speed-signal processing chip which is electrically connected, a rotation speed signal is transmitted to the light emitting diode which issues a change of photochromism according to the rotation speed signal that has been received.