Most labour-saving household appliances contain an electric motor of some description. They are the workhorse of these appliances and most of them are capable of coping with the work loads inflicted upon them. However, some motors, either through poor design or as a result of manufacturers’ cost limitations, are inadequate for the job they are required to do. Adequate or not, at some point it is almost inevitable that they will fail or simply wear out. To delay this, use the appliance with some care and attention, be aware of its limitations and carry out regular inspection and servicing. This will prevent small problems escalating into major ones
Not only do the sizes of motors vary greatly between products, so too do the ways in which they work. To diagnose faults successfully and service or repair appliances, a working knowledge of motors is essential. The following provide a basic introduction to the various types, a description of how they work, the appliances in which each may be found and their particular advantages and drawbacks. Specific problems can be found on individual appliances. Read the rest of this entry »
Unlike the pre-set speed control, variable control allows a greater variation in motor speeds. The motor is a plain AC series-wound brush motor and consequently it is incapable of any variation in speed on its own.
Speed is governed by a separate speed control unit. This unit consists of a printed circuit board with a number of solid-state components, often called the speed module or motor control module. In simple terms, this device interrupts the power supply to the motor at regular intervals. In effect, it pulses the motor. If the pulsing is increased, the motor will run faster and if pulsing is slowed, the motor will run slower. Read the rest of this entry »
The brush roll is supported on bearings at each end so the barrel rotates freely. Types of bearings, barrels and brushes differ from model to model as well as between manufacturers. Some manufacturers supply individual parts for the brush roll, such as brush strips, bearings and barrel; others supply only complete assemblies. The brush roll on some models may have removable brush strips, whereas others may be a solid brush roll of wood or plastic with fixed brushes. A small selection is shown here to highlight the differences. Read the rest of this entry »
The upright style of vacuum cleaner is perhaps the best for large areas of carpet. It is especially good at removing dirt embedded within the pile and pet hairs from the surface, even on sculptured carpets. A drawback with the basic upright cleaner is its difficulty with cleaning stairs. The problem has been overcome with the modern combination of upright and cylinder cleaner. This type may be the best option if you have large areas of fitted carpet and staircases. The motor within the upright cleaner creates the airflow (suction) and drives a rotating brush roll, often called an agitator barrel. Read the rest of this entry »
This type of cleaner, which cleans purely by suction, is better suited to situations other than large carpeted areas: rugs, car interiors, large areas of hard flooring, walls, curtains and furniture. Carpeted stairs are also much easier to vacuum with a cylinder cleaner.
Suction-only carpet cleaning does not remove dirt and grit from the pile base in the same way that the beating and sweeping action of the upright models. However, a machine has been developed that combines the cylinder model with the powered brush roll of the upright vacuum. This type of cylinder appliance has the option of a powered cleaning head attachment that can be connected when required for large carpeted areas. This attachment has a revolving brush roll which is similar to that of the upright cleaner and the suction is supplied by the motor of the cylinder cleaner. Read the rest of this entry »