Abstract:
An apparatus for cleaning floor surfaces and the like includes a cleaning head and a vacuum head to apply water on the surface for a continuous cleaning and vacuum operation. A single water passage of the apparatus is adapted to be connected to an automatic central water supply and drain system to supply water to and withdraw used water from the apparatus alternately through the single water passage in a controlled manner. Fresh water and used water containers are provided for temporarily storing the fresh and used water respectively. A valve device is used to selectively direct the water flow from the single water passage to the fresh water container and water flow from the used water container to the single water passage. Dirt particles are separated from water and air, and are collected in a removable bin for periodic dumping. The apparatus of the invention assures a fully automatic and efficient wet cleaning and vacuuming operation.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This patent application claims the benefit of Applicant&#39;s provisional patent application 60/275,130, filed on Mar. 13, 2001. 
    
    
     THE FIELD OF THE INVENTION 
     The present invention relates to an apparatus for cleaning surfaces such as floors and the like, is more particularly directed to an apparatus for cleaning surfaces with an automatic water supply and drain system. 
     BACKGROUND OF THE INVENTION 
     Cleaning systems that circulate and spray liquids are widely used for cleaning carpets, upholstery, fabric, wall coverings and hard surfaces such as floors of concrete and ceramic tile, etc. In one such system, known as continuous flow cycling, a liquid cleaning solution is sprayed toward the surface being cleaned. A vacuum source simultaneously creates a high velocity air stream that draws the atomized liquid toward the surface, along the surface, or into the material in the case of carpeting, then upwardly away from the surface. This extracts soil, debris and other foreign materials along with the cleaning solution. A typical example of such cleaning systems is described in U.S. Pat. No. 6,055,699, issued to Cho on May 2, 2000. Cho&#39;s system includes a tank and a cleaning tool head that is coupled to the tank by a vacuum hose and by a liquid supply tubing. In operation a liquid cleaning solution is supplied through the liquid supply tubing to a lower row of nozzles of the cleaning tool head spray the liquid onto the surface to be cleaned through a chamber of the cleaning tool head. At the same time, a motor in the tank is operated to draw a vacuum through the vacuum hose that is in fluid communication with the chamber of the tool. However, in such a recycling manner, the liquid cleaning solution is reused within a period of time and therefore the cleaning result will be adversely affected if the cleaning liquid in the tank is not frequently replaced and the tank is not properly cleaned each time. 
     Another type of surface cleaning system not recycling the cleaning liquid will overcome the above mentioned shortcomings. U.S. Pat. No. 919,606, issued to Rocke et al. on Apr. 27, 1909 describes a central vacuum cleaning system having suction pipes and water supply pipes installed in a building structure and accessible at each floor of the building. A cleaning head having a brush, water passage and vacuum passage with a nozzle is provided to be connected to the water pipes and the suction pipes by means of a flexible water tubing and vacuum hose which extend from the cleaning head. In operation Rocke et al.&#39;s central vacuum system having been started, a vacuum is created in the vacuum hose. When the valve of the water passage is opened, a stream of water is carried from the supply tubing to the brush to allow the operator to flush the floor or surface being cleaned at the same time to loosen the dirt by the usual scrubbing operation. When the dirt is loosened from the surface being cleaned and is thoroughly mixed with the water, the water is shut off and the vacuum nozzle is pressed down into close proximity with the surface or floor, in order to allow the water and dirt to be drawn through the vacuum passage into the central system. However, during Rocke et al.&#39;s scrubbing operation to clean and loosen the dirt, most loosened particles and water cannot be drawn into the system because the vacuum nozzle is not pressed down into close proximity with the surface, and therefore the operation is not continuous and efficient. Additionally, the dirt mixed with the used water will be drawn into the central vacuum system which results in difficulty cleaning the dirt remaining in the vacuum pipes especially when the dirt is allowed to dry therein. 
     Therefore, there is a need for an improved surface cleaning apparatus which overcomes the shortcomings of the prior art. 
     SUMMARY OF THE INVENTION 
     One object of the present invention is to provide an apparatus for cleaning a surface, which is adapted for use with a liquid supply and drain system to achieve automatic liquid supply and drain during a surface cleaning operation. 
     Another object of the present invention is to provide an apparatus for cleaning a surface having a single liquid passage alternately to supply fresh liquid for the cleaning and to remove the used liquid during a continuous cleaning and vacuuming operation. 
     In accordance with one aspect of the present invention, an apparatus for cleaning a surface is provided. The apparatus includes a cleaning head for applying a liquid onto the surface and cleaning same, and a vacuum head for removing a mixture of used liquid, air and particles from the surface under a vacuum action. A fan device is provided for generating the vacuum action of the vacuum head. Means are provided for separating the used liquid, air and particles from the mixture respectively, and containing the separated particles. A used liquid container is provided for containing a volume of the used liquid separated from the mixture. A single liquid passage which is adapted to be connected at a first end thereof to an external liquid supply and drain system has valve means at a second end thereof for establishing selective fluid communication of the single liquid passage with one of the cleaning head and the used liquid container. Thus, the liquid can be supplied to the cleaning head and the used liquid can be withdrawn from the used liquid container alternately through the single liquid passage 
     A liquid supply container is preferably provided for containing a volume of liquid and supplying the liquid to the cleaning head. The valve means of the single liquid passage are connected to both the liquid supply container and the used liquid container for selective fluid communication of the single liquid passage with one of the liquid supply container and the used liquid container, so that liquid can be supplied to the liquid supply container and the used liquid can be withdrawn from the used liquid container alternately through the single liquid passage in a controlled manner in order to assure a continuous cleaning and vacuuming operation. 
     A casing structure is preferably provided which has a open bottom and houses the cleaning head, vacuum head, the liquid supply container and the used liquid container, the separating means and the fan device. The cleaning head and the vacuum head are exposed at the open bottom to the surface being cleaned. The single liquid passage is preferably formed with a hollow section of a handle which is pivotally attached to the casing and has a hose extension so that the free end of the hose can be connected to a wall outlet of the external liquid supply and drain system while the apparatus is being used for cleaning an indoor surface such as floors and the like. 
     Sensors are preferably installed in the liquid supply container and the used liquid container for sensing the liquid level and are adapted to be electrically connected to the external liquid supply and drain system. Electrical conductors for delivering electric current to power the apparatus and for transmitting electrical signals from the apparatus to the external liquid and supply system are preferably incorporated with the hose which forms a section of the single liquid passage. 
     The apparatus of the present invention assures an efficient continuous cleaning and vacuuming operation and eliminates the need to manually supply and drain cleaning liquid such as water. 
     Other advantages and features of the present invention will be better understood with reference to preferred embodiments of the invention described hereinafter. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Having thus generally described the nature of the present invention, reference will now be made to the accompanying drawings, showing by way of illustration the preferred embodiments thereof, in which: 
     FIG. 1 is a perspective view of an apparatus for cleaning surfaces in accordance with one embodiment of the present invention; 
     FIG. 2 is a schematic cross-sectional illustration showing various components of the apparatus of FIG. 1; 
     FIG. 3 is a perspective view of a vacuum head of the apparatus of FIG. 1; 
     FIG. 4 is a perspective view of a body member of the apparatus of FIG. 1; 
     FIG. 5 is a perspective view of the cleaning head of the apparatus of FIG. 1; 
     FIG. 6 is an exploded perspective view of the cleaning head of FIG. 5, showing the details of a drive chain for rotating the brushes; 
     FIG. 7 is an exploded view of a single rotatable brush of the cleaning head of FIG. 5; and 
     FIG. 8 is a perspective view of a wheel assembly for adjustably supporting the apparatus of FIG. 1 to facilitate the movement thereof. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings, particularly FIGS. 1 and 2, an apparatus which is capable of washing the floor and removing sand and other dirt particles from the floor surface is generally indicated by numeral  10 . The apparatus  10  includes a casing structure  12  having an open bottom  14 , and a handle  16 . The handle  16  has a forked section  18  at one end thereof which is pivotally attached to opposite sides of the casing  12  and a gripping section  20  at the other end thereof, so that the apparatus  10  can be conveniently pushed or pulled to move on the floor surface by a user gripping the handle  16  at various angular positions. A main section of the handle  16  between the forked section  18  and the free end is hollow, forming a single water passage  22 . 
     The apparatus  10  further includes a cleaning head  24  and a vacuum head  26  both of which are supported by the casing  12  and are exposed to the floor surface at the open bottom  14  of the casing  12 . A first container  28  is provided above the cleaning head  24  for containing a volume of cleaning liquid, such as water and for supplying the water to the cleaning head  24 . A second container  30  is provided at a lower position within the casing  12  but is spaced apart from the floor when the cleaning head  24  and the vacuum head  26  contact the floor surface. The second container  30  is used for containing a volume of the used water. A bin  32  is removably supported within the casing  12  and is positioned above the vacuum head  26  and the second container  30 . The bin  32  having a mesh  34  attached on its inner side works as a depository for collecting sand and other dirt particles  35  and permitting used water to drain through the mesh  34  into the second container  30 . The bin  32  is slidably received in an enclosure  36  defined by the second container  30 , the vacuum head  26 , a body member  38  and a fan device  40 , and can be slidably removed from the enclosure  36 , through an opening (not shown) in one side of the casing  12  when a cover member  42  in the side of the casing  12  is opened so that sand and dirt particles  35  collected in the bin  32  can be periodically dumped from the open top of the bin  32 . 
     A connecting hose  46  interconnects the major hollow section of the handle  16  and both the first and second containers  28 ,  30  by means of a three-way connector  44 . The three-way connector  44  has a first opening (not indicated) connected to the first container  28 , a second opening (not indicated) connected to the second container  30 , and a third opening (not indicated) connected to the interconnecting hose  46  which also forms a section of the single water passage  22 . A first one-way valve  48  is positioned in the first opening of the three-way connector  44  to permit water to flow only from the single water passage  22  to the first container  28  but not in reverse, and a second valve  50  is positioned in the second opening of the three-way connector  44  to permit water to flow only from the second container  30  to the single water passage  22  but not in reverse. 
     Reference will now be made to FIGS. 2 and 3. The vacuum head  26  generally includes a single piece of sponge  27  having a plurality of cavities  52  at the bottom thereof which contacts the floor surface. Each cavity  52  has a substantially triangular cross-section having an opening  54  at the inner side of the sponge  27 , a main opening  56  in the bottom of the sponge  27  and a round hole  58  (only one shown by broken lines in FIG. 3) extending from the top of the cavity  52  vertically through the sponge  27 . Thus, the side opening  54  forms an inlet of the vacuum head  26  for receiving a mixture of water, air and dirt particles under a vacuum action and the hole  58  forms an outlet for discharging the mixture when the main opening  56  of each cavity  52  is covered by the floor surface being cleaned. 
     The one-piece sponge  27  is removablly attached to the casing  12  of FIG.  1  and the second container  30  so that the sponge  27  can be conveniently replaced when required. 
     The body member  38  which is supported within the casing  12  of FIG.  1  and is positioned on the top of the vacuum head  26 , includes a single piece in an L-shape having a plurality of fluid passages  60  (only one shown by broken lines in FIG.  4 ). Each fluid passage  60  has an opening  62  in a lower bottom surface  64  of the L-shaped body member  38  and an opening  66  in an upper bottom surface  68  of the body member  38 . The openings  62  of the body member  38  are aligned with and in fluid communication with the vertical holes  58  of the sponge  27  and the openings  66  are positioned at the top of the bin  32  near an outer side thereof and are in fluid communication with the bin  32 . The fluid passage  60  includes a curved section  61  near the opening  66  to direct the mixture flow drawn from the vacuum head  26  downwards into the bin  32 . 
     A fan inlet  70  is positioned at the top of the bin  32  near its inner side, and is in fluid communication with the bin  32 . An air filter  72  is preferably provided within the fan inlet  70 . The fan device  40  further includes a plurality of exhaust nozzles  74  which extend downwardly along the body member  38  and the vacuum head  26  and are positioned close to the floor surface being cleaned. The fan device  40  which is also supported within the casing  12  of FIG. 1 is designed in a configuration to define, in combination with the second container  30 , the vacuum head  26  and the body member  38 , the relatively sealed enclosure  36  so that a vacuum action generated by the fan device  40  is effective at the vacuum head  26  through the passage formed by the holes  58 , passages  60  and the enclosure  36 . 
     Reference will now be made to FIGS. 2,  5 ,  6  and  7 . The cleaning head  24  includes a base body  76  for supporting a plurality of rotatable brushes  78 . The base body  76  defines a chamber  79  having an open top which is covered by a base cover  90 . The base cover  90  includes an inlet  92  for receiving fresh water and a plurality of small openings  94  extending through the bottom of the base body  76  so that fresh water entering the inlet  92  will spread throughout the chamber  79  and be discharged from the small openings  94 , onto the floor surface to be cleaned. 
     A plurality of cylindrical extensions  96  extend downwards from the bottom of the base body  76  and each of the extensions  96  includes a threaded mounting bore  97  in its bottom end. 
     Each rotatable brush  78  includes a cylindrical body  98  having an annular groove  100  and a central hole  102  extending through the cylindrical body  98 . Each brush  78  is rotatably attached to the base body  76  by receiving the cylindrical extension  96  extending through the central hole  102  of the brush body  98  and being held in position by a shoulder screw  104  that engages the threaded mounting bore  97  in the end of the cylindrical extension  96 . The rotatable brushes  78  are rotated by an endless flat belt  106  which is positioned partially around each of the brush bodies  98  and is tensioned to maintain a tight contact with each brush body  98 . The belt  106  is axially restrained within the grooves  100  of the of the brush bodies  98 . A driving shaft  108  which extends through an opening  112  in the base cover  90  and an opening  114  in the base body  76  has a pulley  110  at the bottom end thereof. The flat belt  106  is also positioned partially around the pulley  110  and is tensioned in contact with the pulley  110  so that when the driving shaft  108  is coupled to a motor  116  and is driven by the motor  116 , the pulley  110  will rotate all the rotatable brushes  78  by means of the flat belt  106 . 
     A motor/pump assembly  118  is provided between the first container  28  and the cleaning head  24  to pump water from the first container  28  to the cleaning head  24 . A valve  120  is provided in the outlet of the motor/pump assembly  118  for selectively directing water flow. The valve  120  has a first position in which the pumped water flow is directed through the inlet  92  into the chamber  79  of the cleaning head  24  for washing the floor surface being cleaned, and a second position in which the pumped water flow from the first container  28  is directed into the second container  30  through a by-pass passage  121 . 
     A vertical rod  122  is installed in the first container  28  with two built in switches  124 ,  126 . Switch  124  is in a lower position at about 10% of the height of the first container  28  and switch  126  is in an upper position at about 90% of the height of the first container  28 . Around the rod  122  is provided a float member  128  with a built-in magnet (not shown) that activates the switches  124  and  126  when the float member  128  approaches the switches respectively. An opening  129  is provided at the top of the first container  28  to permit air to flow in and out when water level in the first container  28  changes. 
     Similarly, a vertical rod  130  is installed in the second container  30  with two built in switches  132  and  134 . Switch  132  is in a lower position at about 5% height of the second container  30  and switch  134  is in an upper position at about 75% of the height of the second container  30 . A float member  136  with a built-in magnet (not shown) is positioned around the vertical rod  130  to activate switches  132 ,  134  when approaching the switches respectively. Guiding plates  138  are provided to prevent the used water drained from the bin  32  from flowing over the float member  136  because sand residues can obstruct the free movement of the float member  136 . It also should be noted that a pipe  140  connected to the three-way connector  44  of the single water passage  22  and extending into the second container  30  should reach close to the bottom thereof to ensure a substantially complete withdrawal of the used water from the second container  30 . 
     Referring to FIGS. 1 and 2, when the cleaning operation begins, the motor/pump assembly  118  starts to pump water from the first container  28  through the outlet  92  into the chamber  79  of the cleaning head  24 . At this moment, the valve  120  is positioned to close the by-pass passage  121 . The water in the chamber  79  flows down through the openings  106  onto the floor surface being cleaned. At the same time the motor  116  drives brushes  78  in rotation which scrub the wet floor surface and loosens dirt particles from the floor surface. Meanwhile, apparatus  10  is being pushed forward to the left so that the cavities  52  of the sponge  27  of the cleaning head  26  push water mixed with sand and other dirt particles on the floor surface towards the narrow end of the cavities  52  to be vacuumed. 
     A vacuuming operation is conducted simultaneously. A powerful motor (not shown) drives the fan device  40  to generate high air flow from the vacuum head  26  through the fan device  40 . The air flow is concentrated on the inner side openings  54  of cavities  52  of the vacuum head  26  to create a powerful vacuum action which is capable of lifting water and dirt particles from the floor surface being cleaned, and mixed with air. The air flow having relatively high velocity carries used water and dirt particles through the narrow passages formed by the vertical hose  58 , and passages  60  and is directed downwards through the curved section  61  into the bin  32 . Because the cross-section of the bin  32  is much larger than the total cross-section of the narrow passages formed by vertical hose  58 , and passages  60 , the velocity of the air flow is much smaller, only about {fraction (1/20)} or {fraction (1/100)} of the velocity of the air flow in the passages formed by vertical hose  58 , and passages  60 . When entering the bin  32  the air flow substantially loses its momentum resulting from the high velocity thereof, and the used water and dirt particles carried by the air flow will fall down under their own weight while the air flow at a relatively low velocity is being drawn up through the air filter  72  to enter the inlet  70  of the fan device  40 . The dirt articles  35  are collected within the bin  32  while the used water is draining through the mesh  34  into the second container  30 . The air flow entering the inlet  70  of the fan device  40  is directed into the relatively narrow nozzles  74  so that the exhausting air flow from nozzles  74  will have a relatively high velocity and impinge the floor surface that has just been cleaned in order to facilitate the drying of the cleaned floor surface. 
     The apparatus is connected to a central water supply and drain system (not shown) through a hose  142  and a connector assembly  144  which is attached to a wall outlet of the system. The system includes a hydro-electrical device with a controller and is adapted to supply water under pressure and withdraw water under a vacuum action through a single water pipe which terminates at the wall outlet. The central water supply and drain system is fully automated according to predetermined programs and electrical signals sent from sensors attached with user apparatus, such as switches  124 ,  126 ,  132  and  134  of the apparatus  10 . This system is fully described in Applicant&#39;s co-pending U.S. patent application Ser. No. 10/093,509 entitled REMOTE CONTROLLED WATER FLOW AND DRAIN SYSTEM and filed on Mar. 11, 2002now U.S. Pat. No. 6,568,425, the entire specification of which is incorporated herein by reference. Electrical conductors for transmitting electrical signals from the switches  124 ,  126 ,  132  and  134  as well as for delivering electrical current to power the motors for the fan device  40  and the motor/pump  118  can be incorporated into the hose  142  and terminate at the connector assembly  144  which in combination with the wall outlet is used to establish a quick and safe fluid and electrical connection. This combined connector is fully described in the Applicant&#39;s co-pending U.S. patent application Ser. No. 10/93,505 entitled COMBINED CONNECTOR FOR FLUID AND ELECTRICAL CONNECTION, and filed on Mar. 11, 2002now U.S. Pat. No. 6,685,491 , the entire specification of which is incorporated herein by reference. A control pad  146  is provided on the top of the casing  12  for the user to manually initiate and terminate a cleaning operation. The valve  120  is located at one side of the casing  12  so that the valve  120  is accessible for a manual operation. 
     Referring to FIGS. 1,  2  and  8 , a retractable wheel assembly  148  is provided to facilitate the movement of apparatus  10  either in a cleaning direction (toward the left of FIG. 2) or in an idle direction (toward the right of FIG.  2 ). The wheel assembly includes four wheels  150  rotatably supported by four vertical rods  152  with racks at the top thereof. The four rods  152  are adjustably supported to the casing  12  and are driven by two shafts  154  which have pinions at the ends thereof and rotatably supported by the casing  12 . The shafts  154  are driven by a motor  156  supported by the casing  12  through belts  158 ,  160 . 
     The cleaning head  24  and the vacuum head  26  are preferably supported by spring means (not shown) to the casing  12 . When the apparatus  10  is moved in the cleaning direction, the motor  156  being controlled by the control pad  146 , drives the wheels  150  up to a predetermined position so that both the rotatable brushes  78  and sponges  27  contact the floor surface under a spring force while the apparatus  10  is moving on the wheels  150 . When the apparatus  10  is moved in the idle direction, the motor  156 , being controlled by the control pad  146 , drives the wheels  150  down to lift the rotatable brushes  78  and sponge  27  from the floor surface. This operation can be fully automated, for example, by sensors (not shown) incorporated into the handle  16 , sensing a pulling and pushing force on the handle, and sensing the pivotal side of the handle  16  with respect to the casing  12 . The control pad  146  will control the position of the wheels  150  in response to the signals from these sensors. 
     During cleaning of the floor surface the water contained in the first container  28  is being used and air is entering the first container  28  through opening  129 . When the water level in the first container  28  drops to the level of the switch  124 , switch  124  is activated to signal the central water supply and drain system to pump water through the single water passage  22 . Under the water pressure in the single water passage  22 , valve  50  is pressed closed and valve  48  is pressed open so that the water can only be directed into the first container  28 . Opening  129  on the top of the first container  28  permits air to escape when the first container  28  is filling with water. When the water level reaches the switch  126 , the switch  126  signals the central water supply and drain system to turn off its pump. 
     Also, during cleaning of the floor, the used water is being collected in the second water container  30 . When the water level in the second container  30  rises to the level of switch  134  the switch  134  signals the central water supply and drain system to start its pump in reverse to generate a vacuum action in the single water passage  22 . Being effected by the vacuum action in the single water passage  22 , the valve  48  closes and the valve  50  opens so that used water in the second container  30  is removed under the vacuum action through the single water passage  22  into the central water supply and drain system and will be directed into a proper drainage. 
     The system is fully automated such that when the system receives a signal for a water withdrawal request while the system is pumping water through the single water passage  22  into the first container  28 , the system will immediately reverse its pump and switch to a water withdrawal operation to ensure an immediate water withdrawal from the second container  30 . Similarly, when the system receives a water supply signal while the system is withdrawing water from the second container  30  through the single water passage  22 , the system will immediately reverse its pump and switch into a water supply operation to ensure the immediate water supply to the first container  28 . Thus, a continuous cleaning and vacuuming operation of the apparatus  10  will not be interrupted for water supply or used water removal. 
     It is noted that a volume of used water remains in the single water passage  22  when fresh water is to be pumped into the first container  30  so that the volume of used water remaining in the single water passage  22  is pumped together with the fresh water into the first container  28 . However, this will not cause any problems for the cleaning and vacuuming operation and does not substantially affect the cleaning performance. Nevertheless, this problem can be overcome by using a valve  50  which can be closed only when the pressure in the single water passage  22  is above a certain level and a valve  48  which can be only opened when the pressure in the single water passage  22  is above the same level. With such valves  48 ,  50  the central water supply and drain system is programmed such that at the beginning of each water supply operation, the system will pump the water under a limited pressure level for a short period of time to ensure that the used water remaining in the single water passage  22  should be pumped back to the second container through the opened valve  50  while the valve  48  remains closed. After the predetermined short period of time the system pumps water through the single water passage  22  at a higher pressure to ensure that the valve  50  is pressed closed and the valve  48  is pressed open to direct the fresh water into the first container  28 . 
     After a cleaning operation is completed, the user can manually switch the valve  120  at the side of casing  12  to drain unused water in the first container  28  through the by-pass passage  121  into the second container  30 , and then manually start a water withdrawal operation by using the control pad  146  on the casing  12  to remove water from the second container  30 . During this water withdrawal operation, the system will disregard the signal sent by switch  132  and terminate the water withdrawal operation only when the system detects a no-water condition in the single water passage  22 . Thus, water can be substantially removed from the apparatus and the apparatus can be properly stored. The sand and other dirt particles collected in the bin  32  can be dumped periodically. 
     In another embodiment of the present invention the cleaning head  24  and vacuum head  26  can be formed as a tool head, but are separated from the other components of the apparatus  10 . The tool head can be connected to the remaining components of the apparatus  10  by a flexible water supply tube and a vacuuming hose. So that the separated cleaning head  24  and vacuum head  26  are in a relatively compact shape which is convenient for moving around and cleaning corners. 
     In yet another embodiment of the present invention the cleaning head  24  does not include rotatable brushes and instead includes flanges (not shown) which in combination with the vacuum head  26  form coverage on the surface being cleaned. This type of cleaning head eliminates the scrubbing operation and is particularly for cleaning carpeting surfaces. 
     In a further embodiment of the present invention the apparatus  10  does not include the first container  28 . The three-way connector  44  of the single water passage  22  is connected directly to the cleaning head  24  and to the second container  30  so that water can be supplied directly from the external central water supply system to the cleaning head  24  and the used water can be withdrawn from the second container  30  alternately through the single water passage  22 . Thus, a continuous cleaning and vacuuming operation can be conducted until the second container  30  is filled up with the used water. A second continuous cleaning and vacuuming operation will begin after the used water is withdrawn from the second container  30 . 
     Modifications and improvements to the above-described embodiments of the present invention may become apparent to those skilled in the art. For example, liquid detergent can be added into water either through the external central system or through an additional container attached to the apparatus. The foregoing description is intended to be exemplary rather than limiting. The scope of the invention is therefore intended to be limited solely by the scope of the appended claims.