Patent Publication Number: US-2018028039-A1

Title: Liquid dispensing cleaning system and methods of use

Description:
BACKGROUND 
     The present disclosure relates to mops or similar cleaning implements. More particularly, it relates to manually operable, liquid dispensing mops. 
     Mop assemblies of the type used for applying liquids (e.g., water, cleaning solutions, floor wax, disinfectants, etc.) to a floor surface commonly include a mop head, a handle by which the mop head can be manually moved along the surface, and a reservoir containing the liquid. The reservoir is usually connected to a nozzle or dispensing tube situated near the mop head so that liquid can be deposited onto the mop head or onto the floor surface at a position close to the mop head to facilitate application or spreading of the liquid over the floor surface. The flow of liquid from the reservoir is typically controlled by a valve, which is normally closed to stop the flow of liquid through the valve, but can be opened to allow liquid from the reservoir to flow through the valve. The valve is generally actuated by the operator in order to permit dispensing of the liquid at a time and place desired for optimal liquid usage efficiency. One advantage of such liquid dispensing mop assemblies is that there is no need for the mop operator to apply the liquid to the surface in a separate step; instead, it can be done as part of the mopping operation, thereby increasing the efficiency of the mopping process. 
     In many conventional liquid dispensing mop assemblies, the reservoir is disposed on or adjacent the handle, typically low on the handle just above the mop head. Although this makes for convenient location of the reservoir, it increases the weight and bulkiness of the mop assembly, making it more difficult and tiring to use since the weight of the reservoir (and contained liquid) is located a relatively large distance from the handle pivot point that must be overcome by a greater user-applied moment or stress when swinging or pushing the mop during normal use. Some mop assemblies attempt to avoid these problems by separating the reservoir from the mop handle so that the reservoir does not have to be moved back and forth with the handle during the mopping process; however, such systems can be cumbersome and awkward to manipulate as the connection between the dispensing tube and the reservoir can interfere with use of the mop. 
     Other concerns with conventional liquid dispensing mop assemblies relate to re-filling of a depleted reservoir. With some designs, the reservoir is a permanent structure of the mop itself. In many instances, it can be difficult for a user to quickly re-fill the permanent reservoir without spillage. Conversely, other constructions provide the reservoir in the form of a container apart from the mop itself, with the mop having brackets or other structures for removably receiving the container. A depleted container can readily be replaced with a new container of liquid, but accidental spillage may invariably occur. Moreover, the mechanisms affording operator control over the dispensing of liquid are not ergonomically correct or convenient, and/or can be quite complex and thus costly. 
     In light of the above, a need exists for improved liquid dispensing cleaning systems, such as liquid dispensing mops. 
     SUMMARY 
     Some aspects of the present disclosure are directed toward a cleaning system. The cleaning system include a lower unit, a liquid dispense assembly, and a reservoir unit. The lower unit includes a shaft and media holder. The shaft defines a first end, a second end opposite the first end, and an interior passage open to the first end. The media holder is connected to the shaft adjacent the second end. The liquid dispense assembly is connected to the first end and includes a housing and a drainage tube. The housing forms an open chamber. The drainage tube is carried by the housing. The reservoir unit includes a bottle and a cap. The bottle is adapted to contain a liquid and terminates at an open end. The cap covers the open end. The system is configured to provide a loaded arrangement in which the reservoir unit is selectively retained within the chamber. Further, the system is configured to be manually operable in the loaded arrangement between a closed state and a dispensing state. In the closed state, the drainage tube is displaced from the cap. In the dispensing state, a portion of the drainage tube passes through the cap for delivering liquid from the bottle to the interior passage. With this construction, the reservoir unit is easily assembled to and removed from the liquid dispense assembly. Further, the mechanisms by which an operator can selectively dispense liquid from the reservoir unit are straightforward and easy to operate. In some embodiments, the liquid dispense assembly includes a plunger for operator-prompted dispensing of liquid, with the plunger arranged to be actuated by a pressing force applied by an operator&#39;s hand otherwise grasping the housing. In other embodiments, the cap includes or carries a valve, such as a bifurcating valve, and the drainage tube includes an insertion segment configured to repeatedly slide through the bifurcating valve in a non-destructive manner. 
     Other aspects of the present disclosure are directed toward a liquid dispense assembly for use with a mop apparatus. The liquid dispense assembly includes a housing, a plunger, a drainage tube, and a hub. The housing defines a leading section, an intermediate section, and a trailing section. The intermediate second forms an open chamber for selectively receiving a reservoir unit. The leading section defines an interior passageway open to an end of the housing and terminating at an orifice opposite the end. The plunger is slidably coupled to the trailing section. The drainage tube is attached to the orifice and defines a lumen open to the chamber and the interior passageway. Further, the drainage tube includes an insertion section for selectively interfacing with a reservoir unit. The hub is slidably disposed about the drainage tube. With this construction, the liquid dispense assembly can be assembled to a shaft of a mop apparatus, and provides an ergonomically convenient mechanism for manually-prompted liquid dispensing. In some embodiments, the liquid dispense assembly further includes a spring biasing the hub in a direction of the trailing section. 
     Yet other aspects of the present disclosure are directed toward a method of cleaning. The method includes loading a reservoir unit into a liquid dispense assembly of a mop apparatus. The reservoir unit includes a bottle containing a liquid and a cap covering an open end of the bottle. A plunger of the liquid dispense assembly is then depressed to cause a drainage tube of the liquid dispense assembly to pass through the cap. Commensurate with the step of depressing, the drainage tube is open to an interior passage of a shaft of the mop apparatus so as to dispense liquid from the bottle onto a surface to be cleaned. In some embodiments, an entirety of the reservoir unit moves relative to the drainage tube with the step of depressing the plunger. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a perspective view of a cleaning system in accordance with principles of the present disclosure, including a reservoir unit loaded to liquid dispense assembly; 
         FIG. 1B  is a perspective view of the cleaning system of  FIG. 1A  and illustrating the reservoir unit apart from the liquid dispense assembly; 
         FIG. 2  is a perspective, exploded view of a liquid dispense assembly useful with the system of  FIG. 1A ; 
         FIG. 3  is a longitudinal, cross-sectional view of a housing useful with the liquid dispense assembly of  FIG. 2 ; 
         FIG. 4  is a cross-sectional view of the housing of  FIG. 3 , taken along the line  4 - 4 ; 
         FIG. 5  is a cross-sectional view of the housing of  FIG. 3 , taken along the line  5 - 5 ; 
         FIG. 6  is an enlarged perspective view of a drainage tube useful with the liquid dispense assembly of  FIG. 2 ; 
         FIG. 7  is an exploded perspective view of the drainage tube of  FIG. 6 ; 
         FIG. 8  is a longitudinal cross-sectional view of the drainage tube of  FIG. 6 ; 
         FIG. 9  is a longitudinal cross-sectional view of a portion of the liquid dispense assembly of  FIG. 3 , illustrating assembly of a plunger to the housing; 
         FIG. 10A  is an enlarged perspective view of a hub useful with the liquid dispense assembly of  FIG. 2 ; 
         FIG. 10B  is an end view of the hub of  FIG. 10A ; 
         FIG. 10C  is a cross-sectional view of the hub of  FIG. 10B , taken along the line  10 C- 10 C; 
         FIG. 11  is a longitudinal cross-sectional view of a portion of the liquid dispense assembly of  FIG. 3 , illustrating assembly of the drainage tube of  FIG. 6  and a biasing assembly to the housing of  FIG. 3 ; 
         FIG. 12  is an enlarged longitudinal cross-sectional view of a portion of a reservoir unit useful with the cleaning system of  FIG. 1A ; 
         FIG. 13A  is a longitudinal cross-sectional view of a portion of the cleaning system of  FIG. 1A , illustrating a closed state of the cleaning system; 
         FIG. 13B  is an enlarged cross-sectional view of a portion of the view of  FIG. 13A ; and 
         FIG. 14  is a longitudinal cross-sectional view of a portion of the cleaning system of  FIG. 1A , illustrating a dispensing state of the cleaning system. 
     
    
    
     DETAILED DESCRIPTION 
     One embodiment of a cleaning system  20  in accordance with principles of the present disclosure is shown in  FIGS. 1A and 1B . The cleaning system  20  includes a cleaning apparatus (e.g., a mop apparatus)  22  and a reservoir unit  24 . In general terms, the reservoir unit  24  contains a volume of liquid and is selectively or removably received by the mop apparatus  22 . As a point of reference,  FIG. 1A  depicts the reservoir unit  24  mounted to the mop apparatus  22  in a loaded arrangement of the system  20 , whereas in the unloaded arrangement of  FIG. 1B , the reservoir unit  24  is removed from the mop apparatus  22 . In addition to facilitating selective mounting of the reservoir unit  24 , the mop apparatus  22  includes various features that promote user-prompted dispensing of liquid from the reservoir unit  24  onto the surface to be cleaned as described in greater detail below. 
     The mop apparatus  22  generally includes a lower unit  30  and a liquid dispense assembly  32 . The lower unit  30  is assembled to the liquid dispense assembly  32 , and includes or carries various implements for cleaning. The liquid dispense assembly  32 , in turn, is configured to receive the reservoir unit  24 , and includes components operable for dispensing liquid from the reservoir unit  24  to the lower unit  30 . In some embodiments, the liquid dispense assembly  32  is formed apart from and assembled to the lower unit  30 ; alternatively, portions of the lower unit  30  and the liquid dispense assembly  32  can be integrally formed. 
     The lower unit  30  can assume a variety of forms generally appropriate for a desired end-use application; the present disclosure is not limited to the exemplary formats reflected in the drawings. The lower unit  30  can include a shaft  40  and a media holder  42 . The shaft  40  is configured for coupling to (or is integrally formed with one more components of) the liquid dispense assembly  32 , and forms an interior passage (hidden in the views of  FIGS. 1A and 1B ). In some embodiments, the shaft  40  can be akin to a hollow tube. Regardless, the interior passage serves as conduit for directing liquid from the liquid dispense assembly  32 . The shaft  40  can alternatively be viewed as a mop handle of the apparatus  22 . As used herein, the term “mop handle” has its commonly understood definition: an elongated member having a first, proximal or lower end  50  adjacent the media holder  42 , and a second, distal or upper end  52  opposite the first end  50 . In some embodiments, the shaft  40  can have an aspect ratio (i.e., length to width ratio) of about 10:1 or greater. For many hand-held implements, a typical cross-section width dimension of the shaft  40  is in the range of about 0.75 inch to about 1.5 inch (about 18 mm to about 38 mm). Similarly, the shaft  40  can have a length of about 20 inches to 60 inches or more depending on the intended utility of the mop apparatus  22 . The shaft  40  can be of a set length or can be adjustable in length (e.g., the shaft  40  can have a telescoping configuration). 
     The media holder  42  is the portion of the mop apparatus  22  (or similar cleaning apparatus) adapted to receive, support or carry a cleaning media (not shown), and can assume a wide variety of forms. The media holder  42  can be, for example, a mop head in the form of a substantially flat or platen media holder, but may be any other suitable structure. The media holder  42  can be adapted to receive any cleaning media format such as woven or nonwoven fabric or paper media as used in so-called flat mops; braided, twisted or woven textile strings or stripes of fabric as used in so-called string or strip mops; squeegees and various brush-like materials useful for scrubbing floors and other surfaces. 
     The media holder  42  can be connected to the shaft  40  at or adjacent the first end  50  in various manners. For example,  FIGS. 1A and 1B  depict one exemplary connection in the form of a coupling joint  60  that may provide a fixed union, thereby holding the media holder  42  in a fixed orientation with respect to the shaft  40 . In other embodiments, a swiveling and/or pivoting union can be provided, thereby permitting the media holder  42  to remain attached to the shaft  40  yet assume more than one orientation with respect to the shaft  40 . 
     As evidenced by the above descriptions, the cleaning systems of the present disclosure are not limited to any particular end use cleaning format. It is to be understood that descriptions of the present disclosure in terms of a mop is for convenience and ease of understanding of the description. It is fully contemplated by the inventor that the scope of the present disclosure is not limited to use with a floor mop, but applies to other implements useful for cleaning surfaces or spreading or otherwise applying liquids to a surface including cleaning tools or systems intended for use, for example, on floors, walls, sinks, toilets, windows, etc. In other words, the term “mop” is used herein to refer to any implement that includes a cleaning material fastened to a handle that can be used to clean any surface. 
     One embodiment of the liquid dispense assembly  32  is shown in greater detail in  FIG. 2 , and includes a housing  70  and a drainage tube  72 . The housing  70  is configured to selectively receive and retain the reservoir unit  24  ( FIG. 1B ). The drainage tube  72  is carried by the housing  70 , and is configured to selectively interface with the reservoir unit  24  in a manner that permits or prevents the flow of liquid from the reservoir unit  24  as described below. In this regard, the fluid dispense assembly  32  includes one or more additional components that facilitate operator-prompted control over the drainage tube  72 /reservoir unit  24  interface, for example a plunger  74  and a biasing assembly  76  as described in greater detail below. 
     The housing  70  includes or defines a leading section  80 , an intermediate section  82 , and a trailing section  84 . In general terms, the leading section  80  is configured for assembly to the shaft  40  ( FIG. 1A ), and supports the drainage tube  72 . The intermediate section  82  extends between the leading and trailing sections  80 ,  84 , and forms or defines an open chamber  86  sized to selectively receive the reservoir unit  24  ( FIG. 1B ). The trailing section  84  provides a convenient handling surface for a user, and is optionally configured to retain the plunger  74  (where provided). The housing  70  can be an integrally formed body in some embodiments; alternatively, one or more of the sections  80 - 84  can be separately formed and subsequently assembled (e.g., the trailing section  84  can be a grip body formed apart from the intermediate section  82 ). 
     In certain respects, geometry features associated with the housing  70  are selected in accordance with the geometries of one or more other components connected to the housing  70 . With this in mind, and with additional reference to  FIG. 3 , the leading section  80  forms or defines a neck  90  and a collar  92 . The neck  90  is configured for assembly to the shaft  40  ( FIG. 1B ), whereas the collar  92  is configured to maintain the drainage tube  72  and the optional biasing assembly  76 . 
     The neck  90  has a generally tubular construction, and defines an interior passageway  100 . The neck  90  is sized and shaped for assembly to the shaft  40  ( FIG. 1B ), and can incorporate various features that facilitate a liquid-tight connection. For example, an outer diameter of the neck  90  can correspond with a diameter of the passage (not shown) formed by the shaft  40  such that the housing  70  is assembled to the shaft  40  via insertion of the neck  90  into the shaft passage. The neck  90  can include one or more channels or grooves  102  each adapted to receive an O-ring (not shown), thereby promoting a secure, leak-proof engagement between the neck  90  and an inner surface of the shaft  40 . The neck  90  can optionally further include or more additional features that promote fastened connection between the shaft  40  and the housing  70 , such as a slot  104  adapted to receive a snap ring or similar attachment component. The neck  90  can be configured for attachment to the shaft  40  in a wide variety of other manners (e.g., friction fit, mechanical fastener, adhesive, welding, etc.). In yet other embodiments, the housing  70  (or at least the leading section  84 ) can be integrally formed with the shaft  40 . Regardless, the interior passageway  100  of the neck  90  is fluidly open or connected to the passage of the shaft  40 . 
     The collar  92  can assume various forms, and generally includes or defines a floor  110  and an outer wall  112 . The floor  110  is formed at a transition between the neck  90  and the collar  92 , and defines a central orifice  114  that is open to the interior passageway  100 . A size and shape of the orifice  114  is configured for receiving a portion of the drainage tube  72  ( FIG. 2 ) as described below. As best shown in  FIG. 4 , one or more optional air bleed holes  116  are defined through a thickness of the floor  110  at locations radially spaced from the central orifice  114 . The air bleed holes  116  are open to the interior passageway  100  ( FIG. 3 ), and promote pressure equalization during a liquid dispensing operation as well as drainage of any liquid that may accumulate within the roller  92  due to imperfect sealing with drainage tube  72 . Returning to  FIGS. 2 and 3 , the outer wall  112  projects from the floor  110  to form a cavity  118  within which the biasing assembly  76  is received. In this regard, the outer wall  112  is optionally shaped as a right cylinder, defining a diameter sized to slidably receive a component of the biasing assembly  76  as described below. Alternatively, the outer wall  112  can have other constructions that may or may not circumferentially enclose the cavity  118 . 
     The intermediate section  82  includes a side wall  130  and a funnel  132  that combine to at least partially define the chamber  86 . The funnel  132  serves as a transition between the side wall  130  and the leading section  80 . A shape of an inner surface  134  of the side wall  130  generally corresponds with a shape of the reservoir unit  24  ( FIG. 1B ), such that the reservoir unit  24  can be generally retained against the inner surface  134 . With additional reference to  FIG. 5 , the side wall  130  terminates at opposing edges  136 ,  138 . As shown, the edges  136 ,  138  are laterally spaced from one another, creating a gap or opening  140  (referenced generally in  FIG. 5 ) to the chamber  86 . In other words, the chamber  86  is open-sided, with a size and shape of the gap  140  selected to allow easy insertion and removal of the reservoir unit  24 . In some embodiments, geometry of the inner surface  134  approximates a semi-circle as shown, although other shapes are also acceptable. As identified in  FIG. 2 , a lateral projection  142  is formed along a length of each of the edges  136 ,  138 , and provides an opening for placement of an operator&#39;s finger(s) when attempting to remove the reservoir unit  24  from the chamber  86 . Other constructions are also acceptable (e.g., a hole or notch in the side wall  130 ). In other embodiments, edges  136 ,  138  can be uniform along an entirety of the intermediate section  82 . 
     The funnel  132  tapers in diameter from the side wall  130  to the collar  92 , defining a continuous surface commensurate with that of the outer wall  112 . Thus, in some embodiments, the chamber  86  is circumferentially enclosed along the funnel  132  (as compared to the open construction of the chamber  86  along the side wall  130 ). As described below, the tapering shape of the funnel  132  serves to guide insertion of the reservoir unit  24  ( FIG. 1B ) into the collar  92 . 
     With specific reference to  FIGS. 2 and 3 , the trailing section  84  is configured to receive the plunger  74 , and includes or defines a ring  150  and a grip  152 . A channel  154  extends through the trailing section  84 , and is open to the chamber  86 . The ring  150  and the grip  152  can thus be annular bodies, with an outer diameter of the grip  152  being less than that of the ring  150  (and of a shape defined by the side wall  130 ). With this construction, a shoulder  156  is established opposite a terminal end  158  of the grip  152 . The grip  152  is sized and shaped for ergonomic handling by a palm of operator&#39;s hand in some embodiments, although other configurations are equally acceptable. As generally reflected by  FIG. 3 , the trailing section  84  can be separately formed and assembled to the intermediate section  82 ; alternatively, the housing  70  can be an integral, homogenous body. 
     The housing  70  can optionally include or incorporate additional features conducive to operator handling. For example, and as identified in  FIGS. 2 and 5 , a series of optional ribs  159  can project from the side wall  130  to provide increased strength while reducing the amount of material. 
     Returning to  FIG. 2 , the drainage tube  72  is generally configured for mounting within the leading section  80  of the housing  70 , and to selectively interface with the reservoir unit  24  ( FIG. 1B ) when disposed within the chamber  86 . One embodiment of the drainage tube  72  is shown in greater detail in  FIG. 6 , and includes or defines a first end  160  opposite a second end  162 , and a lumen  164 . The lumen  164  extends through the drainage tube  72 , and is open to the first and second ends  160 ,  162 . In some embodiments, the drainage tube  72  includes an insertion segment  170  otherwise terminating at the first end  160 . The insertion segment  170  can assume various constructions appropriate for interfacing with a corresponding component of the reservoir unit  24 . In some embodiments, for example, the insertion segment  170  includes a plurality of spaced apart, circumferentially arranged splines  172 , adjacent ones of which are separated by a slot  174 . The splines  172  (and corresponding slots  174 ) extend longitudinally (i.e., parallel to a central longitudinal axis of the drainage tube  72 ), and are adapted, in some embodiments, for slidable insertion into and retraction from a valve structure such as a bifurcating valve allowing air to enter between the splines  172  (i.e., via the slots  174 ). Other constructions are also envisioned, commensurate a valve or other self-sealing configuration provided with the reservoir unit  24 . 
     Other optional features provided with the drainage tube  72  can be selected to promote assembly with the housing  70  ( FIG. 2 ) and/or to interface with the biasing assembly  76  ( FIG. 2 ). For example, the drainage tube  72  can include a flange  180 , a guide segment  182  and a mounting segment  184 . The insertion segment  170  projects from the flange  180 , with an outer diameter of the flange  180  being greater than an outer diameter collectively defined by the splines  172 . The guide segment  182  extends from the flange  180  in a direction opposite the insertion segment  170 , and is generally configured to interface with a component of the biasing assembly  76  as described below. The guide segment  182  can be cylindrical in shape, optionally having an outer diameter less than the diameter of the flange  180 . The mounting segment  184  terminates at the second end  162  and is sized and shaped for mounted assembly to the housing  70  as described below. For example, the mounting segment  184  can be cylindrical in shape, having a stepped reduction in outer diameter to generate a rim  186  for reasons made clear below. The drainage tube  72  can be assembled to the housing  70  in a wide variety of manners, such that the drainage tube  72  can incorporate other constructions differing from the mounting segment  184  as shown. 
     The drainage tube  72  can be an integral, homogenous body. Alternatively, the drainage tube  72  can be formed by two (or more) separate components, such as shown in  FIG. 7 . More particularly, the drainage tube  72  is optionally generated by assembly of a head member  190  and a base member  192 . The head member  190  includes or forms the insertion segment  170 , the flange  180 , and a coupling body  194  forming exterior threads  196 . The base member  192  includes or forms the guide segment  182  and the mounting segment  184 , and forms an interiorly threaded surface  198 . The head member  190  is assembled to the base member  192  via threaded engagement between the coupling body  194  and the interiorly threaded surface  198 . Regardless, the lumen  164  is continuous through the drainage tube  72  as further reflected by  FIG. 8 . 
     Returning to  FIG. 2 , the plunger  74  is generally configured to facilitate user-actuated dispensing of liquid from the reservoir unit  24  ( FIG. 1B ), and can assume a variety of forms. In some embodiments, the plunger  74  includes a shaft  200 , a capture body  202  and a button  204 . The shaft  200  is sized to be slidably received within the channel  154  (referenced generally in  FIG. 2 ) of the housing trailing section  84  (e.g., an outer dimension of the shaft  200  is less than a diameter of the channel  154 ), and has a length greater than a length of the channel  154 . The capture body  202  and the button  204  are attached to opposite ends of the shaft  200  and present an enlarged diameter such that once assembled to the housing  70 , the plunger  74  cannot inadvertently be removed (i.e., the capture body  202  and the button  204  cannot pass through the channel  154 ). For example, and as shown in  FIG. 9 , longitudinal sliding movement of the plunger  74  relative to the housing  70  is constrained by the capture body  202  contacting the shoulder  156 , and by the button  204  contacting the terminal end  158 . In some embodiments, the button  204  (and/or the capture body  202 ) is formed apart from the shaft  200 . Assembly of the plunger  74  to the housing  70  entails insertion of the shaft  200  through the channel  154 , followed by assembly of the button  204  to the shaft  200 . A wide variety of other mounting configurations are equally acceptable. 
     Returning to  FIG. 2 , the optional biasing assembly  76  can assume a variety of forms and in some embodiments includes a hub  210  and a spring  212 . One exemplary construction of the hub  210  is shown in  FIGS. 10A-10C , and includes a hub body  220  and a platform  222 . The hub body  220  has an annular shape, extending between opposing, first and second ends  224 ,  226 . The platform  222  is located intermediate the opposing ends  224 ,  226 , and is perpendicular to a central axis of the hub body  220 . As identified in  FIG. 10C , the platform  222  defines opposing, first and second faces  230 ,  232 . A central opening  234  is formed through a thickness of the platform  222 , and is sized to co-axially receive a portion of the drainage tube  72  ( FIG. 2 ). Further, drainage holes  236  are optionally formed through a thickness of the platform  222  at locations radially spaced from the central opening  234  for reasons made clear below. Regardless, the platform  222  combines with the hub body  220  to define a capture region  238  for receiving the spring  212  ( FIG. 2 ). The hub body  220  further forms a central bore  240  between the first end  224  and the first face  230  of the platform  222 . The bore  240  is fluidly open to the central opening  234  (as well as the drainage holes  236  where provided). The bore  240  has a stepped diameter, defining a shelf  242  intermediate the platform  222  and the first end  224 . A diameter of the bore  240  between the shelf  242  and the first end  224  corresponds with a component of the reservoir unit  24  ( FIG. 1B ), with a geometry of the shelf  242  and the reservoir unit component (e.g., a cap) selected in tandem such that the reservoir unit  24  can be placed into the bore  240  in abutting contact with the shelf  242 . A diameter of the bore  240  between the shelf  242  and the platform  222  is selected to slidingly accommodate corresponding features of the drainage tube  72 , including the optional flange  180  ( FIG. 7 ) as described below. 
     Returning to  FIG. 2 , the spring  212  can assume a variety of forms appropriate for interfacing with the hub  210  as described below. In some embodiments, the spring  212  is a helically wound compression spring. Other configurations are also acceptable, and in some embodiments the spring  212  can be replaced with any other biasing member or mechanism format. 
     Mounting of the drainage tube  72  and the biasing assembly  76  to the housing  70  is shown in  FIG. 11 . The drainage tube  72  is attached to the housing collar  92 , locating the insertion segment  170  away from the floor  110 . For example, the mounting segment  184  can be press-fit into the orifice  114 , establishing a fixed relationship (e.g., the drainage tube  72  does not move relative to the housing  70 ). Other mounting configurations are equally acceptable that may or may not entail a fixed arrangement. Regardless, the drainage tube lumen  164  is fluidly open to the interior passageway  100 . The hub  210  is slidably disposed over the drainage tube  72 , including the guide segment  182  of the drainage tube  72  being received within the central opening  234  of the platform  222 . As shown, a diameter of the central opening  234  is less than a diameter of the flange  180 . Upon final assembly, then, the hub  210  is arranged such that the first face  230  of the platform  222  selectively contacts or abuts the flange  180 . Further, the insertion segment  170  is located within the bore  240  of the hub  210 , with the hub body  220  being radially spaced from the insertion segment  170  (e.g., the insertion segment  170  and the flange  180  freely slide relative to the hub  210  within the bore  240 ). The spring  212  is captured between the floor  110  and the second face  232  of the platform  222 , and biases the hub  210  away from the floor  110  to the arrangement of  FIG. 11 . As a point of reference,  FIG. 11  reflects a normal or “closed” state of the liquid dispense assembly  32 . In the closed state, the spring  212  biases the hub  210  such that platform  222  abuts the flange  180 ; because the drainage tube  72  (and thus the flange  180 ) is spatially fixed relative to the floor  110 , a static interface is established, preventing the hub  210  from moving beyond (or upwardly relative to the orientation  FIG. 11 ). When a force is applied to the hub  210  sufficient to overcome a biasing force of the spring  212 , the hub  210  is caused to move toward the floor  110  for reasons made clear below. Upon removal of this force, the spring  212  biases the hub  210  back to the closed state of  FIG. 11 . As shown, the shelf  242  is displaced away (i.e., above relative to the orientation of  FIG. 11 ) from the insertion segment  170  of the drainage tube  72  in the closed state. 
     Returning to  FIG. 1B , the reservoir unit  24  generally includes a bottle  250  and a cap  252 . The bottle  250  defines an internal volume for containing a liquid, and terminates at an open end or orifice  254  (referenced generally) that is covered by the cap  252  as shown in  FIG. 12 . The cap  252  effectively defines a face  256  that closes the open end  254 . The face  256  can have a self-sealing or self-closing attribute, whereby a body can be inserted through the face  256  and following subsequent removal of the body, the face  256  (or other component associated with the face  256 ) self-seals or self-closes. For example, the face  256  can carry or form or be open to a valve structure (not shown). In some embodiments the valve is of a type known to those of skill in the art as bifurcating valve. A bottle cap containing a bifurcating valve may be obtained from Liquid Molding Systems, Inc., Midland, Mich. As a point of reference, while bifurcating valves are sometimes employed to permit flow in response to an external pressure, such as squeezing of the bottle  250 , and to prevent fluid flow absent such pressure, operation of the liquid dispense assemblies of the present disclosure is premised upon passing a body through the bifurcating valve (as opposed to squeezing the bottle  250 ). Other valve constructions are also acceptable. In other embodiments, the face  256  can be or include a self-sealing or self-closing membrane or material layer(s). Though not shown, the cap  252  can optionally include a lid that may be attached to the cap  252  by a hinge, for example, to prevent unexpected flow of liquid through the face  256  during periods of non-use. 
     The bottle  250  can assume various shapes and sizes, and in some embodiments is constructed to exhibit at least some longitudinal rigidity (e.g., the bottle  250  will not overtly deform when subjected to the external forces described below). While the bottle  250  may have a substantially rigid construction, in other embodiments the bottle  250  can be constructed to deform in response to a squeezing force. In yet other embodiments, the bottle  250  can be entirely deformable (e.g., akin to a bag or pouch), with the reservoir unit  24  further including one more outer containers that surround the bottle  250  and provide some level of longitudinal rigidity (e.g., a bag-in-a-box design). Further, the reservoir unit  24  may comprise more than one chamber, thereby permitting the contents of multiple chambers to react, combine or mix prior to or during dispensing. The liquid contained by the reservoir unit  24  can be any format desired. Non-limiting examples of liquids useful with the present disclosure include water, water-based cleaning solutions, other liquid cleaning solutions, floor wax, etc. Further, cleaning systems of the present disclosure can include two (or more) of the reservoir units  24  each containing the same or a different liquid; optionally, the system also include a carrier for additional reservoir units such as holder adapted to carry one or more reservoir units and to be worn on the body of the operator. 
     As mentioned above,  FIG. 1B  illustrates the reservoir unit  24  apart or disassembled from the mop apparatus  22 . The reservoir unit  24  can easily be loaded into the chamber  86  in multiple fashions by an operator via insertion through the gap  140  ( FIG. 5 ). For example, the reservoir unit  24  is manipulated to first locate a trailing end of the bottle  250  against the capture body  202  of the plunger  74  and then allowed to slip the cap  252  on the shelf  242 . It will be recalled that in the normal (or closed) state of  FIG. 13A , the spring  212  biases the hub  210  away from the floor  110 , including the shelf  242  being displaced away from the insertion segment  170 . Thus, during loading of the reservoir unit  24  (in which the cap  252  is engaged with or abuts against the shelf  242 ), the insertion segment  170  of the drainage tube  72  does not interface with the cap  252 , and no liquid is released or dispensed from the reservoir unit  24 . 
     The loaded arrangement of the cleaning system  20  (with the reservoir unit  24  loaded into the liquid dispense assembly  32 ) is shown in  FIGS. 13A and 13B , and reflects a closed or “normal” state. For ease of illustration, the lower unit  30  ( FIG. 1A ) is omitted from the views. The reservoir unit  24  is fully loaded into the chamber  86 , including the cap  252  engaged with the shelf  242  of the hub  210 . The spring  212  biases the hub  210  to the arrangement shown, with the hub  210 , in turn, locating the cap  252  longitudinally away from the drainage tube  72 . That is to say, in the closed state, the insertion segment  170  does not interface with the cap  252  such that the seal provided by the cap face  256  remains intact, preventing release of liquid from the reservoir unit  24 . It should be noted that in the view of  FIG. 13A , the plunger  74  is arranged such that capture body  202  is in contact with the bottle  250 . This may naturally occur where the plunger shaft  200  can freely slide relative to the grip  152  and the liquid dispense assembly  32  is held in an upright fashion (e.g., the orientation of  FIG. 13A ); under these circumstances, the plunger  74  may self-articulate into the arrangement of  FIG. 13A  under the force of gravity. However, so long as no external forces are placed onto the plunger  74  (e.g., so long as the operator does not exert an overt pressing force onto the plunger button  204 ), a biasing force of the spring  212  is sufficient to maintain the closed or normal state under the combined weight of the reservoir unit  24  and the plunger  74 . In other words, absent an overt action by the operator, the liquid dispense assembly  32  remains in the closed state and liquid is not released from the reservoir unit  24 . 
     To dispense liquid from the reservoir unit  24 , the operator applies a manual force onto the plunger  74  in a direction of the reservoir unit  24  (represented by the arrow “D” in  FIG. 13A ) while keeping the housing  70  relatively stationary. For example, while handling the housing  70 , the operator can hold the grip  152  in the palm of a single hand and apply a pressing force on to the plunger button  204  with the thumb of the single hand in an ergonomically convenient fashion. Other techniques for applying a manual force on to the plunger  74  are also acceptable. Regardless, the force placed on to the plunger  74  is transferred on to the reservoir unit  24  and in turn on to the hub  210  (due to a longitudinal rigidity of the bottle  250 ). Once the applied force overcomes a bias of the spring  212 , the hub  210  and the reservoir unit  24  are caused to move in tandem in a direction of the floor  110 , including the hub  210  sliding relative to the drainage tube  72 . A spring force of the spring  212  is selected such that an adult human applying the pressing force solely with his/her thumb can readily overcome the bias of the spring  212  in some embodiments. Regardless, the reservoir unit  24  is caused to move relative to the housing  70  and the drainage tube  72  to the dispensing state of  FIG. 14 . 
     As the liquid dispense assembly  32  is transitioned from the closed state ( FIG. 13B ) to the dispense state ( FIG. 14 ), the drainage tube  72  is caused to interface with the reservoir unit  24 . More particularly, the insertion segment  170  passes through the cap  252  (and in particular the sealed or valved face  256 ) such that in the dispense state of  FIG. 14 , the drainage tube lumen  164  is fluidly open to an interior of the bottle  250 . Liquid contained in the bottle  250  will flow (e.g., due to forces of gravity) through the drainage tube lumen  164  and into the interior passageway  100 . Air is allowed to flow into the bottle  250  via the slots  174  ( FIG. 6 ) along the insertion segment  170  of the drainage tube  72  while liquid passes through the drainage tube lumen  164 . It will be recalled that the interior passageway  100  is fluidly connected to one or more other conduits or passages (such as an interior passage of the shaft  42  ( FIG. 1A )), delivering the so dispensed liquid to an outlet or exit orifice of the mop apparatus  22 . When the operator desires to discontinue the dispensing of liquid, the pressing force applied to the plunger  74  ( FIG. 13A ) is released; the spring  212  then biases the hub  210  back to the closed state, including the insertion segment  170  being withdrawn from the cap  252 . With removal of the insertion segment  170 , the cap  252 , and in particular the valved or self-sealing face  256 , closes or seals the bottle  250 . With embodiments in which the cap  252  includes or carries a bifurcating valve, the optional splined construction of the insertion segment  170  (e.g., as shown in  FIG. 6 ) readily slides into and out of interfacing contact with the bifurcating valve in a non-destructive manner, allowing an operator to repeatedly transition between the closed and dispensing states with the bifurcating valve consistently returning to a sealed condition upon withdrawal of the insertion segment  170 ; further, the optional splines  172  ( FIG. 6 ) effect a fluid tight seal with a perimeter of the bifurcating valve such that liquid will not overtly flow between the insertion segment  170  and the bifurcating valve perimeter in the dispensing state. Pressure potentially generated between the shelf  242  and the floor  110  as the reservoir unit  24  is transitioned from the closed state ( FIG. 13B ) to the dispensing state ( FIG. 14 ) is relieved via the air bleed holes  116  (referenced generally) in the floor  110  and the drainage holes  236  in the platform  222 . Further any excess liquid can drain through the holes  236 ,  116  and into the interior passageway  100 . 
     The liquid dispense assemblies of the present disclosure can assume other formats akin to above explanations but incorporating various modifications. For example, while operation of the liquid dispense assembly  32  in transitioning between the closed and dispensing states has been described as moving or sliding an entirety of the reservoir unit  24  relative to the drainage tube  72 , in other embodiments the liquid dispense assembly can be configured such that the drainage tube  72  is caused to move relative to the reservoir unit  24  in response to an operator-applied force, selectively bringing the insertion segment  170  into and out of engagement with the cap  252 . In some embodiments, such as the example of  FIGS. 13B and 14 , the fluid dispense assembly  32  is configured such that the operator-applied actuation force (e.g., pressing force applied to the button  204  as described above) is applied in-line with a central axis of the shaft  40  ( FIG. 1A ) for ease of operation. 
     Returning to  FIGS. 1A and 1B , the mop apparatuses of the present disclosure can be configured to dispense or distribute liquid delivered by the liquid dispense assembly  32  in various manners. For example, in one non-limiting embodiment, an interior passage of the shaft  40  is fluidly connected to a spout  300  arranged to deposit the so-delivered liquid onto the surface to be cleaned in close proximity to the media holder  42 . Other exit or dispensing orifice constructions are equally acceptable. 
     The cleaning systems, mop apparatus, liquid dispense assemblies and methods of the present disclosure present a marked improvement over previous designs. Individual containers of cleaning solution or other liquids are easily assembled to and removed from the mop apparatus. An operator is afforded the ability to easily dispense a volume of liquid in a controlled fashion by a simple, ergonomically-corrected pressing force applied to a plunger at the handling end of the mop apparatus. 
     Although the present disclosure has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes can be made in form and detail without departing from the spirit and scope of the present disclosure.