Comparison Dreame D20 vs Dreame D20 Pro

The type of dust collector provided in the design of the vacuum cleaner.

Nowadays, there are three main types of dust collectors — a regular bag, a cyclone system and an aquafilter. Also, in some vacuum cleaners (in particular, industrial and fireplace models — see "Product type") dust collectors in the form of rigid containers (tanks) can be used without additional equipment. For such models, the type of dust collector in our catalogue is not specified. As for the three main types, here are their features:

— Bag. A dust collector in the form of a soft bag, simultaneously plays the role of one of the filters: air passes through the walls of the bag, and most of the contaminants are retained. Such containers are simple and inexpensive, while they can be made quite roomy. In addition, the vacuum cleaner with a bag remains operational in any position of the body. On the other hand, as the bag fills up, suction efficiency drops noticeably; and the cleaning procedure is usually quite troublesome — in particular, a lot of dust is raised into the air. Disposable bags, which are available for many models as an additional accessory, are deprived of such a drawback. However, on the other hand, the purchase of such bags is associated with additional expenses. As a result, this type of dust collector, although very popular in modern vacuum cleaners, is much less common...than the "cyclones" described below.

— Cyclone system (bagless). Dust collector based on a cyclone type air cleaner; usually has the form of a plastic bowl of a special shape. The principle of operation of such systems is that the air flow entering the dust collector is twisted into a spiral. In this case, the centrifugal force throws debris and dust out of the formed vortex, and the collected pollution sinks to the bottom of the dust collector. One of the main advantages of "cyclones" is the ease of cleaning: just turn the container over and the contents pour out of it without additional effort, and if desired, the dust collector can be easily washed. In addition, the suction force is practically independent of the degree of filling of the bowl. However, cyclones are somewhat inferior in capacity to bags, but because of the foregoing, this point is usually not fundamental. But the unequivocal disadvantages of this option are the higher cost of the same bags; a lower suction force for the same engine power; as well as a somewhat lower efficiency of catching fine dust. In light of the latter, "cyclones" have to be equipped with additional filters, which also periodically require cleaning. It is also worth bearing in mind that such systems are most effective with a regular, strictly defined position in space. If you deviate from this standard operational position, the efficiency of the dust collector may noticeably decrease, which leads to rapid clogging of the filters.

— Aquafilter. This type of dust collector looks like a container with water: the air drawn in by the vacuum cleaner passes through the liquid, which traps most of the contaminants. Such systems are highly efficient and hygienic: they capture various contaminants well, including even fine dust, without additional filters. In addition, the air released by the vacuum cleaner is additionally humidified which is especially useful in the cold season, when heating dries the air in the room. At the same time, the procedure for cleaning the dust collector itself is very simple and convenient: after cleaning, its contents can simply be poured into the sewer, while no dust rises into the air (unlike the process of cleaning cyclones and especially bags). On the other hand, it is desirable to wash and dry aquafilters after each use, which somewhat complicates maintenance. In addition, most of these vacuum cleaners are quite expensive, the passage of air through the water creates additional noise, and the water itself significantly increases the weight of the unit.
Separately, it is worth emphasizing that the presence of an aquafilter does not mean that the vacuum cleaner is washing (see above) or at least can wet cleaning (see "Cleaning type"). Quite a few models with an aquafilter work only in a dry format — and vice versa, units with a wet cleaning function may well be equipped with other types of dust collectors.

— Aquafilter + bag. This option means that the vacuum cleaner is equipped with two types of dust collectors at once — an aquafilter and a traditional bag. The features of both are described in detail above. Here we note that such models necessarily have a wet cleaning mode (see above) and/or a water suction function — an aquafilter is used for these purposes. But the bag, anyway, is intended for traditional dry cleaning. In general, this is the most common combination of the two types of dust collectors. The other variants described below are much less common.

— Aquafilter + cyclone. A combination similar to the aquafilter with a bag described above. The delivery set of such a vacuum cleaner includes two types of containers: an aquafilter for wet cleaning and/or water suction (this function can also be provided in vacuum cleaners with purely dry cleaning), as well as a cyclone system (see above) for sry cleaning .

— Cyclone system + bag. A combination found exclusively in dry cleaning models. Similar to the combinations described above, most often we are talking about the presence of two replaceable dust collectors of different types in the kit. The specific type is chosen depending on the situation. So, the cyclone system is convenient for collecting relatively large and heavy contaminants, and the bag handles better with fine dust.

The mapping system is provided in many modern robots. It allows you to determine the size of the room and the location of various obstacles present in it, as well as fix the route travelled by the vacuum cleaner. There are various systems according to their principle of operation, among which there are three types. Methods for building a map based on data from a sensor or a camera belonging to the basic level. But building a map using a laser rangefinder (lidar) gives more accurate results and elevates the device to a higher category. Accordingly, the presence of such a system affects the overall cost but provides several advantages. Firstly, cleaning efficiency is noticeably increased: the robot remembers which areas have already been cleaned and pays maximum attention to untreated areas. Secondly, movements are carried out along optimal trajectories, the shortest paths; this saves energy and extends battery life. Thirdly, it becomes possible to effectively clean large spaces of complex shape (for example, the entire apartment). And if the vacuum cleaner is controlled through an application on a smartphone or other gadget, the created map is displayed in this application. It gives various additional features: correcting the collected data, real-time device control, building routes, limiting cleaning through the application (see above), etc. P.

As for the methods of building maps (and further naviga...tion), there are mainly such options:

— Camera. Such systems work because the robot, using a digital camera, “examines” the room, remembering its shape and the location of objects. A fairly simple, inexpensive and at the same time practical way: usually, the camera is supplemented by an object recognition algorithm, thanks to which it can recognize obstacles stored in memory, regardless of their position in space. It is useful when you have items that are frequently moved around, such as chairs. In addition, if the map is displayed in an application on a smartphone, it looks like not just a conventional diagram but a real image, which is very convenient. The disadvantages of this option include perhaps a slightly lower accuracy than that of sensors and even more so rangefinders. However, it is not critical, and in some models, information from the camera can be supplemented with data from sensors, which completely reduces this drawback to zero.

— Sensors. Creating a map through the operation of various special sensors. Most often, such systems use sensors for obstacles and fall protection (see "Robot features"), working in conjunction with an inertial module that determines the current position of the robot in space. Receiving a signal from one of the sensors, the robot saves data on the trigger point; from such points, as a result, the map is formed. It is a fairly reliable method. It is inferior in accuracy to rangefinding cartography (see below) but it is also cheaper. The disadvantages of this type of mapping include some inconvenience when managing via the application. The map is displayed in the form of a scheme map, which is not always convenient for the user. In addition, vacuum cleaners with such systems are unable to respond in advance to a change in the situation — this change is determined only when the sensor is triggered again.

— Rangefinder (laser). Building a map using a laser range finder — lidar. Usually, such a rangefinder covers the space all 360 ° around the vacuum cleaner, scanning the space at a high frequency (hundreds and even thousands of measurements per second in all directions). It allows you to create very accurate maps in a short time and with a minimum of movement in space. In addition, the rangefinder is used not only during the initial mapping but also during further work. Thanks to this, the robot instantly reacts to changes in the environment and corrects the trajectory of movement. The main disadvantage of such systems is their rather high cost. In addition, as in the case of sensors, when controlling the vacuum cleaner from a smartphone, the map is displayed in the form of a scheme map, which is somewhat less convenient than when using cameras.

— Rangefinder + camera. It is the most advanced and functional option: the laser provides high accuracy in determining distances and a quick response to changes in the environment. And the camera allows you to create not just scheme maps but realistic images of premises that are convenient when controlled via a smartphone. The main disadvantage of such combined systems is their very high cost. Therefore, they are extremely rare, mainly in premium robot vacuum cleaners.

We emphasize that in this paragraph we describe the functions of the vacuum cleaner nozzles and not the types of nozzles themselves. It is because one device can have several functions at once: for example, a crevice nozzle, which is also used as a dust nozzle. So the total number of nozzles may differ from the number of items in this list. Although exceptions are possible (when several nozzles of the same type are supplied in the kit, differing in size).

The main functions found in the nozzles of modern vacuum cleaners are as follows: combined (floor/carpet), crevice (including telescopic crevice), dust brush, for sofa, parquet, turbobrush(regular, mini turbobrush or electricturbobrush . However, sometimes the best choice is vacuum cleaners without turbobrushes, and for handheld vacuum cleaners — angle brush, mop, floor polisher (for wiping), for mattresses, for animals, twister for hose, siphon nozzle, flexible hose and...tool adapter. For robots, side brushes are important, which can be one or two. Here is a detailed description of these, as well as some other features:

— Side brush. Function found exclusively in robots (see "Product type"). Such a brush protrudes to the side beyond the body and captures the space on the side. It increases the overall width of the operating area and allows you to effectively clean places that are inaccessible to the main brush of the robot (which is located at the bottom of the body). Typical examples of such places are the space near the walls of the room and at the bases of cabinet furniture, crevices under baseboards, etc. Note that this option is indicated when there is only one side brush; the presence of a pair of such brushes is specified separately (see below).

— 2 side brushes. The presence in the robot vacuum cleaner of two side brushes on both sides of the body. See above for more details on the side brush as a whole. This design option slightly increases the cost but significantly improves efficiency compared to a single side brush. The width of the operating area is evenly increased. And when cleaning hard-to-reach places, it does not matter which side the vacuum cleaner is turned to such a place — there is an additional brush on each side.

— Combined (floor/carpet). A function that allows you to use one nozzle for dry cleaning of various types of floor coverings — both hard (linoleum, parquet, laminate, tiles ...) and carpets. Accessories with this function are extremely popular. They are found in almost all conventional vacuum cleaners (see "Product type"), in many household vacuums, as well as professional models (except hand-held industrial and fireplace vacuum cleaners). The nozzle itself usually has a T-shape, rather large dimensions and a swivel mount that improves mobility. And adjustment for different types of surfaces is carried out due to the retractable brush. The bristles of such a brush are convenient for cleaning hard surfaces. And when cleaning carpets and other fleecy materials, the brush can be removed so that the nozzle fits snugly against the pile and effectively draws dust and small debris out of it.

— Crevice. This function means that the nozzle is equipped with a flat working part with a narrow slot at the end. This design is suitable for cleaning hard-to-reach places — spaces between pieces of furniture, crevices under baseboards, gaps between radiator sections, etc. The width of the crevice nozzle (and, accordingly, the length of the crevice) usually does not exceed the diameter of the vacuum cleaner pipe, but the length of the flat part can be different. Moreover, each option has its advantages: long models can reach further into narrow gaps, while short ones are more manoeuvrable and more comfortable in general.

— Dust. A function that allows you to collect dust from small hard surfaces, such as armrests of chairs, picture frames, lamp shades, etc. Traditional accessories with this ability are in the form of small round brushes but there is another variety — wider nozzles (also with brushes), somewhat similar to a smaller version of the floor/carpet format fixtures (see above). The second variety is often referred to as furniture nozzles. Some of these accessories have removable bristles and can be used as nozzles for a sofa (see below).

— For sofa. A function that allows you to effectively clean the upholstery furniture and other similar items — mattresses, car seats, etc. Brushes with this function can have different designs and application features. The simplest option is a T-shaped device, similar to a reduced combination nozzle (see above), which does not have bristles, but is often equipped with strips of the fine pile — they effectively collect hair and wool from the upholstery. Some of these devices are equipped with removable bristles and can also be used as dust ones (see above). A more expensive and advanced option is beater brushes that provide additional impact; this effect increases efficiency, allowing the removal of dust and other small contaminants even at fairly great depths. Also, some turbobrushes and mini turbobrushes may be intended for upholstered furniture (see below). For vacuum cleaners equipped with such accessories, both this function and the mini turbobrush are indicated in the specifications.

— Parquet. A function that allows you to use the nozzle for effective and gentle cleaning of parquet and other hard floor coverings. A nozzle with this function is similar to the combined one described above. However, the bristles in it are non-removable and they are designed to minimize the risk of damaging the coating. Nevertheless, the specific characteristics of such nozzles may be different. So if you have to work with delicate surfaces — the ability of such an application needs to be specified separately.

— Turbobrush. The working part of a classic turbobrush is a horizontal roller driven by airflow. This design allows you to effectively collect hair, wool and other similar debris (for example, thread). But the specific design and specialization of the turbo brush can be different. Models, where the roller is equipped with bristles, are designed mainly for fleecy surfaces like carpets. And some of these nozzles are reduced in size and are intended for cleaning upholstery furniture (in such cases, the function “for sofa” is also indicated in this list). In turn, rollers with soft short pile are great for smooth surfaces — including rather delicate ones, like parquet. Thus, there may be several turbobrushes in the kit — for different tasks.
Note that the turbobrush must be periodically cleaned from collected contaminants. In addition, such a nozzle slightly reduces the overall suction efficiency since part of the suction power is spent on rotating the roller. Electric versions are deprived of this drawback, but they also have their own disadvantages — see below for more details. Also note that even mechanical turbobrushes are quite expensive, even though their advantages over conventional fixed attachments become noticeable only when cleaning hair and long hair. Therefore, if you do not regularly have to deal with such pollution, it most likely makes sense to choose a vacuum cleaner without a turbo brush.

— Mini turbobrush. A reduced version of the turbobrush — conventional (see above) or electric (see below). Compactness allows to effectively use such a brush in hard-to-reach places and on small surfaces. Actually, the main purpose of most mini-turbo brushes is to clean wool and hair from upholstered furniture. In addition, some of these nozzles are also well suited for cleaning carpets on narrow stairs.

— Electric turbobrush. Devices that are almost completely similar to the turbobrushes described above with the exception that the roller, in this case, is driven not by an air stream but by an electric motor installed in the nozzle itself. The main advantage of electric nozzles is the higher efficiency (with the same suction power). Firstly, such nozzles practically do not affect suction power, while traditional mechanical turbobrushes lose part of this power, spending it on rotating the roller. Secondly, the speed of rotation of the electric turbo brush does not depend on the airflow, and the torque of the electric motor can be quite high. The downside of these advantages is the complexity and high cost of the nozzles, as well as the need to use special tubes and hoses with them, supplemented by wiring to power the electric motor.

— Angle. This function means that the vacuum cleaner is equipped with a device that allows you to place the working nozzle at an angle (usually perpendicular) to the main tube. In this case, the specific design of such a device may be different. In some models, this is an additional adapter in the form of an L-shaped tube on which different nozzles are installed. In others, the L-shaped nozzle itself is made of one type or another — for example, dust (see above). Thirdly, such an adapter or nozzle is equipped with a swivel joint, which allows you to place the working part at different angles. All such devices make it much easier to clean in some hard-to-reach places.
We note that it makes little sense to use angle adapters with combined floor/carpet nozzles (see above) — such devices usually have swivel joints and do not require additional equipment to rotate them.

— Twister for hose. A small cyclone-type container (see "Dust collector") mounted directly on the hose of the vacuum cleaner; usually at the joint with the pipe. Most often is used in vacuum cleaners with a bag. Twister performs several useful functions at once. Firstly, it traps most of the dust and allows you to work longer without cleaning the bag; and cleaning the twister is much easier and faster than cleaning the bag. Secondly, the container on the hose is usually made transparent which makes it easier to monitor the amount of dust collected. Thirdly, it is easier to get a small but necessary item (coin, memory card, etc.) accidentally sucted by the unit from the twister. The disadvantage of such a device is that it makes the hose more bulky and heavy, reducing mobility.

— Siphon nozzle. A function that allows you to use a vacuum cleaner to clean sewage in kitchen sinks. For such cleaning, specialized nozzles are used, which are similar in shape and principle of operation to plungers. The difference is that the suction that clears a clogged pipe is created by the operation of the vacuum cleaner. All units equipped with such nozzles have the function of water suction. However, they may not be washing vacuums(see above) and may not even have the ability of wet cleaning (see “Cleaning type”).

— Flexible hose. The presence of this function is specified for vacuum cleaners that are not related to conventional ones (see "Product type") — the latter is equipped with a hose by default and there is no need to specifically mention this accessory for them. In other cases, a flexible hose can be both the main working accessory (for example, industrial vacuum cleaners, including most handheld ones) and an additional accessory (for example, upright units). In the latter case, the hose allows you to reach places that are inaccessible without such a device when cleaning.

— Adapter for tools. A function that allows the use of a vacuum cleaner in combination with various electric and sometimes pneumatic tools for cleaning production waste right in the process. It is found mainly in professional-level units — industrial (including handheld) and for workshop (household vacuum cleaners are poorly suited for working with large amounts of chips and sawdust). However, the specific design and purpose of such an adapter may be different. Most often, it has the form of a kind of cone, made up of "steps" of different diameters and is used to connect to tools that are originally equipped with nozzles for a vacuum cleaner. At the same time, the dimensions of the "steps" of the adapter correspond to several standard diameters in which nozzles are made on tools. (Some units with this equipment even have an auto-on function when the tool is turned on; see "Built-in socket" for more details). However, before buying such a unit, it's ok to clarify the compatibility of the adapter with specific tool models.
Another version of the "tool" adapter is a kind of cover that covers the area around the place of work and is used mainly with drills and hammers. In such a cover there are two holes: one — with a pipe for connecting a vacuum cleaner, the second — for the working nozzle of the tool. The circumference of the hole for the tool is often made of characteristic "petals", reducing the risk of damage to the drill or other nozzle in case of accidental contact with the adapter. However, such devices are rarely included in the package — they are more popular as separately sold accessories.

In addition to those described above, in modern vacuum cleaners, there are other, more specific functions of nozzles, in particular:

— Washing. Sometimes the presence of this function is specifically indicated for washing vacuum cleaners — mainly to clarify the features of the washing nozzle. So, it can be intended for different surfaces (for smooth floors or carpets/furniture), have different sizes, etc. However, the principle of construction of all such nozzles is the same: the design necessarily has a nozzle for spraying detergent, and the working part usually has the appearance of a thin and rather wide gap. This design most effectively handles with the collection of liquid.

— Ultraviolet lamp. An ultraviolet lamp, built-in in one of the main nozzles — most often in combined for floors/carpets (see above), but exceptions are possible. Such equipment allows the vacuum cleaner to carry out not only ordinary cleaning but also additional disinfection: UV radiation handles well with most pathogens. At the same time, it is harmless to people and pets if you follow the safety rules specified in the documentation for the vacuum cleaner. Of course, we are not talking about one hundred per cent disinfection. However, the use of a UV lamp anyway improves the quality of cleaning.

— Flexible crevice. A special variety of the crevice nozzles described above is with a flexible working part. This design of the nozzle allows it to penetrate even into curved slots that are inaccessible to a traditional rigid design.

— For pets. This function allows you to use the vacuum cleaner to collect hair from pets that tend to shed heavily, especially long-haired dogs and cats. A specialized nozzle for such tasks is an improved “comb”: it effectively removes loose hair, which is immediately drawn in by a vacuum cleaner. And at the same time does not create discomfort for the animal (the main thing is to accustom the pet to the noise of the vacuum cleaner itself).

— Pulverizer. A feature found in some vacuum cleaners with a wet cleaning function (see “Cleaning type”). Usually, it is implemented through a special nozzle designed exclusively for spraying liquid.

The rated voltage of the battery used in the vacuum cleaner with the corresponding type of power supply (see above).

Initially, manufacturers select the characteristics of the battery (including voltage) in such a way that the vacuum cleaner can be guaranteed to deliver the power claimed in the specifications. Therefore, when choosing this indicator often does not play a decisive role. However, it can also be useful in such cases — for the most reliable comparison between models with different battery capacities in ampere-hours. See "Battery capacity" for details.

In addition, voltage data can be useful during operation — for example, to find a spare/replacement battery or a third-party charger.

The operating time of a battery-powered vacuum cleaner (see "Power supply") on a single battery charge.

Usually, the average operating time in normal mode is indicated here. Accordingly, in fact, the battery life of the vacuum cleaner may differ slightly from the claimed one, depending on the chosen application format. Nevertheless, the operating time indicated in the specifications is a fairly reliable indicator; it can be used both for a general assessment of battery life and for comparing the selected vacuum cleaner with other models.

Separately, we note that increasing battery life requires either the use of more capacious (and therefore more expensive and heavier) batteries or a decrease in engine power (and the efficiency of the unit as a whole). So it is worth looking specifically for a long working vacuum cleaner if these moments are outweighed by a long operating time.

The time required to charge the cordless vacuum cleaner fully (see "Power supply").

Larger batteries tend to take longer to charge. On the other hand, modern batteries can use various solutions that speed up the process, so there is no strict dependence here.

Separately, we note that the speed of charging batteries is usually uneven: at first, the process is fast, then it gradually slows down. So if, for example, the specifications indicate a charging time of 2 hours, then charging from 0 to 50% will take a little less than an hour, and from 50% to 100% the remaining time.