Modern washing machines are available in two configurations: top loading and front loading.
The top loading design, most popular in Australia, Canada, the United States, Latin America and some parts of Europe, places the clothes in a vertically-mounted perforated basket that is contained within a water-retaining tub, with a propeller-like agitator in the center of the bottom of the basket. Clothes are loaded through the top of the machine, which is covered with a hinged door. During the wash cycle, the outer tub is filled with water sufficient to suspend the clothing freely in the basket, and the movement of the agitator pulls the clothing downward in the center towards the agitator paddles. The clothing then moves outward and up the sides of the basket to repeat the process. Top-loaders are not well-suited to cleaning large objects such as pillows or sleeping bags due to the tendency for them to just float on the surface of the water without circulating, and the aggressive agitator action can damage delicate fabrics.
In most top loading washers, if the motor spins in one direction, the gearbox drives the agitator; if the motor spins the other way, the gearbox locks the agitator and spins the basket and agitator together. Similarly if the pump motor rotates one way it recirculates the sudsy water; in the other direction it pumps water from the machine during the spin cycle. Because they usually incorporate a gearbox, clutch, crank, etc, top loading washers are mechanically more complex than front loading machines but are generally lower maintenance since there is no need for a door seal (described below).
Arctic BE1200A+ is a front loading budget model sold in 2008 with 6 kg load, LCD indicator, 1200 RPM.The front loading design, most popular in Europe and the Middle East, mounts the inner basket and outer tub horizontally, and loading is through a door at the front of the machine. The door often but not always contains a window. Agitation is supplied by the back-and-forth rotation of the cylinder and by gravity. The clothes are lifted up by paddles on the inside wall of the drum and then dropped. This motion flexes the weave of the fabric and forces water and detergent solution through the clothes load. Because the wash action does not require the clothing be freely suspended in water, only enough water is needed to moisten the fabric. Because less water is required, front-loaders typically use less soap, and the aggressive dropping and folding action of the tumbling can easily produce large amounts of foam.
Front-loaders control water usage through the surface tension of water, and the capillary wicking action this creates in the fabric weave. A front-loader washer always fills to the same low water level, but a large pile of dry clothing standing in water will soak up the moisture, causing the water level to drop. The washer then refills to maintain the original water level. Because it takes time for this water absorption to occur with a motionless pile of fabric, nearly all front-loaders begin the washing process by slowly tumbling the clothing under the stream of water entering and filling the drum, to rapidly saturate the dry clothes with water.
Front loading washers are mechanically simple compared to top-loaders, with the main motor normally being connected to the drum via a grooved pulley belt and large pulley wheel, without the need for a gearbox, clutch or crank. But front-load washers suffer from their own technical problems, due to the drum lying sideways. For example, a top loading washer keeps water inside the tub merely through the force of gravity pulling down on the water, while a front-loader must tightly seal the door shut with a gasket to prevent dripping water onto the floor during the wash cycle. This access door is locked shut during the entire wash cycle, since opening the door with the machine in use could result in water gushing out onto the floor. For front-loaders without viewing windows on the door, it is possible to accidentally pinch fabric between the door and the drum, resulting in tearing and damage to the pinched clothing during tumbling and spinning.
Nearly all front-loader washers for the consumer market must also use a folded flexible bellows assembly around the door opening, to keep clothing contained inside the basket during the tumbling wash cycle. If this bellows assembly were not used, small articles of clothing such as socks could slip out of the wash basket near the door, and fall down the narrow slot between the outer tub and basket, plugging the drain and possibly jamming rotation of the inner basket. Retrieving lost items from between the outer tub and inner basket can require complete disassembly of the front of the washer and pulling out the entire inner wash basket. Commercial and industrial front-loaders used by businesses (described below) usually do not use the bellows, and instead require all small objects to be placed in a mesh bag to prevent loss near the basket opening.
This bellows assembly around the door is the source of problems for the consumer front-loader. The bellows has a large number of flexible folds to permit the tub to move separately from the door during the high speed extraction cycle. On American machines, these folds can collect lint, dirt, and moisture, resulting in mold and mildew growth and a foul odor. Some front-loading washer operating instructions say the bellows should be wiped down monthly with a strong bleach solution, while others offer a special freshening cycle where the machine is run empty with a strong dosing of bleach.
A top-loading washer suffers from none of these continued maintenance problems and needs no regular freshening. During the spin cycle, a top-loading tub is free to move about inside the cabinet of the machine, using only a lip around the top of the inner basket and outer tub to keep the spinning water and clothing from spraying out over the edge.
There are many variations of these two general themes. Top loading machines in Asia use impellers instead of agitators. Impellers are similar to agitators except that they do not have the center post extending up in the middle of the wash tub basket. There is also a top loading variant of the horizontal axis design that is loaded from the top, through a small door in the circumference of the drum. These machines usually have a shorter cylinder and are therefore smaller, but offer the efficiency of a front-loader while eliminating the problems of the flexible bellows. This kind of washing machine is sold and popular in Europe, especially in small households, because it offers the same drum system as front loaders, just with a smaller footprint.
Front-loaded machines are ideal for fitted/finished kitchens, since they can be installed under a countertop/worktop. A front loading washing machine, in a fully-fitted kitchen, is often disguised as an ordinary base cabinet/unit. They are also ideal for small homes and apartments with limited space, because the dryer can be installed directly above the washer.
Many front loading machines have electrical heating elements to heat the wash bath to near boiling. Chemical action is supplied by the detergent and other laundry chemicals. Front loaders use special detergents that are designed to release different chemical ingredients at different temperatures. This is so that different type of stains and soils will be cleaned from the clothes as the wash water is heated up by the electrical heater. Front loaders also need to use low sudsing detergents because the tumbling action of the drum folds air into the clothes load that can cause over-sudsing. Due to the concentration of water and detergent, though, the sudsing issue of front-loaders can also be controlled by simply using less detergent without lessening cleaning action.
Tests comparing front loading and top loading machines have shown that, in general, front-loaders wash clothes more thoroughly, cause less wear, and use less water and energy than top-loaders. As a result of using less water, they require less detergent to be used, or conversely, they can use the same amount of detergent with less water, which increases detergent concentration and increases the amount of chemical action. They also allow a dryer to be more easily mounted directly above the washer.
Top-loaders have had the advantage that they complete a washing cycle much faster and allow clothes to be removed at intermediate stages of the cycle (for instance, if some clothes within a wash are not to be spun). Many current front-loaders, though, can be stopped and added-to or removed-from because the water level in the horizontal tub is still below the door level. They also tend to be easier to load and unload, since reaching into the tub does not require stooping. Again, this issue can be mitigated due to the offering of risers (usually with storage drawers underneath) to raise the door opening closer to the user's level. The top loader's spin cycle between washing and rinsing allows an extremely simple fabric softener dispenser, which operates passively through centrifugal force and gravity. The same objective must be accomplished by a solenoid-operated valve on a front loader. Another advantage to the top loading design is the reliance on gravity to contain the water, rather than potentially trouble-prone or short-lived front door seals.
Traditionally, top loading machines have tended to be more complex mechanically than front loading washers, because the former generally require a gearbox, clutch, crank, etc to perform the wash cycle. However, the recent introduction of direct drive motors has simplified some of the top loading washers on the market. Also, because of the introduction of electronics, modern machines are less complex than the early automatic washers. Consequently, the price of automatic machines, in real terms, has fallen.
The top loading design, most popular in Australia, Canada, the United States, Latin America and some parts of Europe, places the clothes in a vertically-mounted perforated basket that is contained within a water-retaining tub, with a propeller-like agitator in the center of the bottom of the basket. Clothes are loaded through the top of the machine, which is covered with a hinged door. During the wash cycle, the outer tub is filled with water sufficient to suspend the clothing freely in the basket, and the movement of the agitator pulls the clothing downward in the center towards the agitator paddles. The clothing then moves outward and up the sides of the basket to repeat the process. Top-loaders are not well-suited to cleaning large objects such as pillows or sleeping bags due to the tendency for them to just float on the surface of the water without circulating, and the aggressive agitator action can damage delicate fabrics.
In most top loading washers, if the motor spins in one direction, the gearbox drives the agitator; if the motor spins the other way, the gearbox locks the agitator and spins the basket and agitator together. Similarly if the pump motor rotates one way it recirculates the sudsy water; in the other direction it pumps water from the machine during the spin cycle. Because they usually incorporate a gearbox, clutch, crank, etc, top loading washers are mechanically more complex than front loading machines but are generally lower maintenance since there is no need for a door seal (described below).
Arctic BE1200A+ is a front loading budget model sold in 2008 with 6 kg load, LCD indicator, 1200 RPM.The front loading design, most popular in Europe and the Middle East, mounts the inner basket and outer tub horizontally, and loading is through a door at the front of the machine. The door often but not always contains a window. Agitation is supplied by the back-and-forth rotation of the cylinder and by gravity. The clothes are lifted up by paddles on the inside wall of the drum and then dropped. This motion flexes the weave of the fabric and forces water and detergent solution through the clothes load. Because the wash action does not require the clothing be freely suspended in water, only enough water is needed to moisten the fabric. Because less water is required, front-loaders typically use less soap, and the aggressive dropping and folding action of the tumbling can easily produce large amounts of foam.
Front-loaders control water usage through the surface tension of water, and the capillary wicking action this creates in the fabric weave. A front-loader washer always fills to the same low water level, but a large pile of dry clothing standing in water will soak up the moisture, causing the water level to drop. The washer then refills to maintain the original water level. Because it takes time for this water absorption to occur with a motionless pile of fabric, nearly all front-loaders begin the washing process by slowly tumbling the clothing under the stream of water entering and filling the drum, to rapidly saturate the dry clothes with water.
Front loading washers are mechanically simple compared to top-loaders, with the main motor normally being connected to the drum via a grooved pulley belt and large pulley wheel, without the need for a gearbox, clutch or crank. But front-load washers suffer from their own technical problems, due to the drum lying sideways. For example, a top loading washer keeps water inside the tub merely through the force of gravity pulling down on the water, while a front-loader must tightly seal the door shut with a gasket to prevent dripping water onto the floor during the wash cycle. This access door is locked shut during the entire wash cycle, since opening the door with the machine in use could result in water gushing out onto the floor. For front-loaders without viewing windows on the door, it is possible to accidentally pinch fabric between the door and the drum, resulting in tearing and damage to the pinched clothing during tumbling and spinning.
Nearly all front-loader washers for the consumer market must also use a folded flexible bellows assembly around the door opening, to keep clothing contained inside the basket during the tumbling wash cycle. If this bellows assembly were not used, small articles of clothing such as socks could slip out of the wash basket near the door, and fall down the narrow slot between the outer tub and basket, plugging the drain and possibly jamming rotation of the inner basket. Retrieving lost items from between the outer tub and inner basket can require complete disassembly of the front of the washer and pulling out the entire inner wash basket. Commercial and industrial front-loaders used by businesses (described below) usually do not use the bellows, and instead require all small objects to be placed in a mesh bag to prevent loss near the basket opening.
This bellows assembly around the door is the source of problems for the consumer front-loader. The bellows has a large number of flexible folds to permit the tub to move separately from the door during the high speed extraction cycle. On American machines, these folds can collect lint, dirt, and moisture, resulting in mold and mildew growth and a foul odor. Some front-loading washer operating instructions say the bellows should be wiped down monthly with a strong bleach solution, while others offer a special freshening cycle where the machine is run empty with a strong dosing of bleach.
A top-loading washer suffers from none of these continued maintenance problems and needs no regular freshening. During the spin cycle, a top-loading tub is free to move about inside the cabinet of the machine, using only a lip around the top of the inner basket and outer tub to keep the spinning water and clothing from spraying out over the edge.
There are many variations of these two general themes. Top loading machines in Asia use impellers instead of agitators. Impellers are similar to agitators except that they do not have the center post extending up in the middle of the wash tub basket. There is also a top loading variant of the horizontal axis design that is loaded from the top, through a small door in the circumference of the drum. These machines usually have a shorter cylinder and are therefore smaller, but offer the efficiency of a front-loader while eliminating the problems of the flexible bellows. This kind of washing machine is sold and popular in Europe, especially in small households, because it offers the same drum system as front loaders, just with a smaller footprint.
Front-loaded machines are ideal for fitted/finished kitchens, since they can be installed under a countertop/worktop. A front loading washing machine, in a fully-fitted kitchen, is often disguised as an ordinary base cabinet/unit. They are also ideal for small homes and apartments with limited space, because the dryer can be installed directly above the washer.
Many front loading machines have electrical heating elements to heat the wash bath to near boiling. Chemical action is supplied by the detergent and other laundry chemicals. Front loaders use special detergents that are designed to release different chemical ingredients at different temperatures. This is so that different type of stains and soils will be cleaned from the clothes as the wash water is heated up by the electrical heater. Front loaders also need to use low sudsing detergents because the tumbling action of the drum folds air into the clothes load that can cause over-sudsing. Due to the concentration of water and detergent, though, the sudsing issue of front-loaders can also be controlled by simply using less detergent without lessening cleaning action.
Tests comparing front loading and top loading machines have shown that, in general, front-loaders wash clothes more thoroughly, cause less wear, and use less water and energy than top-loaders. As a result of using less water, they require less detergent to be used, or conversely, they can use the same amount of detergent with less water, which increases detergent concentration and increases the amount of chemical action. They also allow a dryer to be more easily mounted directly above the washer.
Top-loaders have had the advantage that they complete a washing cycle much faster and allow clothes to be removed at intermediate stages of the cycle (for instance, if some clothes within a wash are not to be spun). Many current front-loaders, though, can be stopped and added-to or removed-from because the water level in the horizontal tub is still below the door level. They also tend to be easier to load and unload, since reaching into the tub does not require stooping. Again, this issue can be mitigated due to the offering of risers (usually with storage drawers underneath) to raise the door opening closer to the user's level. The top loader's spin cycle between washing and rinsing allows an extremely simple fabric softener dispenser, which operates passively through centrifugal force and gravity. The same objective must be accomplished by a solenoid-operated valve on a front loader. Another advantage to the top loading design is the reliance on gravity to contain the water, rather than potentially trouble-prone or short-lived front door seals.
Traditionally, top loading machines have tended to be more complex mechanically than front loading washers, because the former generally require a gearbox, clutch, crank, etc to perform the wash cycle. However, the recent introduction of direct drive motors has simplified some of the top loading washers on the market. Also, because of the introduction of electronics, modern machines are less complex than the early automatic washers. Consequently, the price of automatic machines, in real terms, has fallen.
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