[box type=”shadow” ]The scrubber-dryer has become an integral part of floor cleaning, whereby new customer requirements are constantly taken into account in development: models with disc or roller technology, depending on floor texture, machines for heavily-furnished areas & the smallest surfaces, platform strategies for improved efficiency & flexibility, eco-concepts for protecting the environment & conserving resources, as well as innovative solutions for better ergonomics. Today, digitisation has found its way into fleet and process management systems, leading the way into the future. A journey into the past & future.[/box]
A question of floor texture: Since the 1950s, scrubber-dryers have been used for interior cleaning of hard and resilient floor areas. The tried-and-tested single-disc technology provides good results and roller brush technology is only seldom employed. This changed in 1986 when Kärcher, a cleaning specialist previously known in particular for high pressure and dust control technology, launched a walk-behind machine with roller brushes on to the market. This is in response to a demand that occurs only regionally: whilst floors in Asia, Southern Europe and USA are often smooth and easy to clean with disc technology, floors in Northern and Central Europe tend to be more structured, i.e. grouted tiles or natural stone with rougher surfaces. Roller brushes, irrespective of the floor texture, deliver improved scrubbing and polishing performance and therefore a more uniform result, even on heavily soiled floors.
Roller brushes work with a high contact pressure, as the contact area on the floor is smaller, and faster rotational speeds can be achieved than with disc brushes. The built-in sweeping function also facilitates cleaning to a large extent, since prior to the use of scrubber-dryers, heavily soiled floors had to always be swept in order to avoid damaging the floor and blocking the suction channel.
Trend No. 2: from the gym to the restaurant?
Scrubber-dryers find new applications: Large, unobstructed areas have always been easy to clean with scrubber-dryers. Models for small, heavily-furnished areas, which are becoming increasingly popular, place higher demands on development. The main focus is not necessarily on speed, as a good cleaner can clean up to 500sqm an hour with a wiping mop. More important are the level of thoroughness and suction of the dirty water, which is not possible in the same quality manually as when using a machine.
In the mid-1990s, Kärcher launches the world’s smallest floor cleaning machine in the market at the time. The machine works with a cleaning fleece instead of roller brushes or disc, while the cleaning and suction unit is operated with an electric motor. The machine designed for niche applications is therefore very compact and manoeuvrable. The demand for ever smaller machines is subsequently met by the design of self-supporting chassis, fresh and dirty water tanks and a compartment for turbine and batteries made from a single plastic part. In the meantime, solutions with roller brushes or disc are available, even for hard surfaces from about 20sqm, making convenient and thorough maintenance cleaning of washrooms, salesrooms and seating areas possible. Innovative steering concepts finally ensure that the brush head can be controlled directly via a steering wheel on some models, which provides high manoeuvrability even for heavily-furnished areas. The use of lithium-ion batteries, which are much lighter than standard batteries and provide a significant weight reduction, has today greatly contributed to convenient operation for the operator.
Trend No. 3: More Function, Less Investment?
Triumph of the platform strategies: Increasing cost pressures and higher customer demands – all sectors have been faced with this challenge to an increasing extent over the years. Floor cleaning is no exception, which is why the demand for a wider variety of versions goes hand in hand with the wish for low investment costs. In the development of new models, the platform strategy, the idea of which was to use as few parts as possible in order to considerably reduce development and production costs, has been successfully employed since the beginning of 2000.
In addition, a certain degree of individualisation is also possible, although the introduction of different individual models is not an efficient and cost-effective answer. The latest machines are freely configurable by the operator in many respects, depending on floor texture, surface and degree of soiling. Roller or disc, battery or cord, with or without protective roof, wide or narrow wheels – the list can be as multifarious as when buying a car, depending on the manufacturer. This includes innovative accessories such as automatic cleaning agent dosing units or systems for setting up different user profiles for operators, service technicians and facility managers.
Trend No. 4: Focusing on the Environment?
Eco concepts on the increase: Depending on the country and its customs, ecology has increasingly become an important topic for building service contractors in recent years. Whereas energy consumption was of less interest for a long time, there are now regions where buildings have their own power outlets for cleaning and the energy consumption is invoiced. This increases the demand for ecologically sustainable solutions.
Today, different manufacturers offer ECO modes, which, depending on the degree of soiling, can reduce the turbine power and in turn adapt the energy consumption to suit the cleaning requirement. Noise emission is another important topic, which is why turbine attenuation has been improved more and more over the years. Kärcher recently positioned itself with a concept for completely climate-neutral cleaning: from the avoidance of CO2 in production and ECO mode control of machines to climate compensation of CO2 emissions in cleaning applications and support of climate projects, sustainability aspects were taken into account.
A further topic that focuses on protecting the environment and conserving resources is water consumption. The better the water demand is adapted to the required cleaning performance, the longer cleaning can take place with one tank and a specific water volume. In this respect, the layout of the rollers or discs as well as the ratio of contact pressure and rotational speed play an important role.
Ergonomics and product design over the course of time: When the first floor polisher was introduced over 100 years ago, the main focus was on floor cleaning: how could work be made easier? Since the 1990s, all functions relating to user-friendliness are regulated under the keyword ergonomics, in some cases also by law. The facets, with this topic also, are diverse: whereas easy manoeuvring and a clear view are important for machines weighing 500kg, the handle position and an individual, precisely controllable traction drive or asymmetric contour, via which the working result is easier to control, for example, are important for tireless working with walk-behind machines. Control elements in prominent colours and easy brush replacement at the push of a button are also ergonomic aspects. Not to be forgotten are the dirty water tanks, where nothing adheres to the surface or are self-cleaning, ideally with an automatic rinsing system – for the operator, this means greater hygiene and more convenient handling than manual cleaning.
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Tracing History
The beginnings of mechanised floor cleaning date back more than 100 years. The first-floor polisher was developed at the beginning of the 20th century in order to simplify the arduous work. In the 1930s, a version for wet floor cleaning is introduced, and in the 1950s, the first scrubber-dryer with vacuum function is launched on to the market. A further milestone in 1986 is the first walk-behind machine with roller brushes, which scrubs, vacuums and sweeps in a single pass and greatly improves cleaning performance on structured floors.[/box]
The product design also makes work easier – even if it is often said that it is not important in the cleaning industry, square metal crates are hard to find on the market. To make work a more enjoyable experience, Kärcher launches in 1998 a machine based on the motorised three wheelers from the motorcycle world. The press release at the time read “due to its attractive appearance and ride comfort, the model promises more enjoyment and greater motivation during the often unpopular task of cleaning”.
Back to the future
Leading the way into automation: The extensive use of partly or even fully automated solutions seems to be still a long way off despite the fact that in 1996 Kärcher developed a cleaning robot and tested it at different airports. Though there are already machines available on the market, they are designed for large surfaces and can only be used efficiently for this purpose. Digitisation and automation will also offer new possibilities for floor cleaning, however always oriented on clear added value for the operator. If safety and efficiency can be combined to 100% in the area of cleaning robots and also realised on small, heavily-furnished areas, this may be a trend for the next 100 years of scrubber-dryers.