Abstract: A voltage controller has an casing, with a plurality of electrical connecting terminals, and housing a signal processing circuit and a power circuit, facing one another and connected to these terminals. A thermally fusible safety device is fitted between the circuits, and is electrically connected between one of the terminals and the power circuit. The safety device has a strip of resiliently deformable and electrically conductive material and a plate-like positioning and support formation. The formation has a seat which forms an opening through which a first end of the strip is connected to the power circuit. A second end of the strip is connected to one of the terminals by a thermally fusible connection. The strip is coupled to the formation with a pre-loading arranged to break the connection of its second end.

Abstract: A brush holder for an electrical motor has an electrically insulating support structure supporting a number of brushes. The support structure has a molded-plastic body incorporating conducting elements forming conductive paths for connecting the brushes to a power supply. A discontinuity is provided in one of the connection paths. A resiliently deformable and electrically conductive strip is connected across the discontinuity with a substantially permanent connection at one end and a heat-meltable connection at the other, with a resilient pre-load tending to break the heat-meltable connection. A voltage drop resistor is provided for operating the motor at a reduced speed. One terminal of the resistor is connected to one side of the discontinuity via a thermally and electrically conducting connection.

Abstract: A brush holder for an electrical motor has an electrically insulating support structure supporting a number of brushes. The support structure has a molded-plastic body incorporating conducting elements forming conductive paths for connecting the brushes to a power supply. A discontinuity is provided in one of the connection paths. A resiliently deformable and electrically conductive strip is connected across the discontinuity with a substantially permanent connection at one end and a heat-meltable connection at the other, with a resilient pre-load tending to break the heat-meltable connection. A voltage drop resistor is provided for operating the motor at a reduced speed. One terminal of the resistor is connected to one side of the discontinuity via a thermally and electrically conducting connection.