Abstract:
A trigger-actuated cleaning device dispenses an aerosol cleaning agent from a pressurized canister. The canister has a female valve assembly. In one form an over cap fits onto the canister over the valve and has a male stem on a pivotable part of the over cap that opens the valve when moved by a rod linked to a remote trigger. The stem is either formed integrally with the over cap or is removably attached to a stem socket formed in the over cap. In another form the actuator is a button having a stem that fits in the female valve.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This is a continuation-in-part of U.S. Ser. No. 09/951,632, filed on Sep. 14, 2001, now U.S. Pat. No. 6,551,001. 

   STATEMENT OF FEDERALLY SPONSORED RESEARCH/DEVELOPMENT 
   Not applicable. 
   FIELD OF THE INVENTION 
   The present invention relates to aerosol spray cans and the like. More particularly it relates to improved over cap/valving structures that render such cans particularly well suited for remote trigger activation. 
   BACKGROUND OF THE INVENTION 
   The cleaning of houses, office buildings, and certain other structures can be challenging due to high ceilings, furniture placed within rooms, and other structural features. For example, the physical dimensions of various furniture can limit one&#39;s ability to clean under them, ceiling corners can be difficult to reach, and bending or crouching to clean floors can strain one&#39;s back. 
   Moreover, people engaging in cleaning operations on a regular basis may be concerned about frequent contact with various chemicals found in cleaning preparations. Regardless of whether this is just a matter of consumer perception, or whether the concerns relate to actual medical or safety issues (e.g. skin irritation), this can affect consumer preferences. Concerns about contacting such chemicals may be perceived as greater when the consumer needs to place their finger in close proximity to a dispenser outlet in order to dispense the chemical, or if the chemical is sprayed in close proximity to where the human&#39;s head is. 
   Hence, there have been a number of attempts to separate the trigger for an aerosol can from the outlet, sometimes by several feet. See e.g. U.S. Pat. Nos. 3,679,319, 3,794,217, 4,789,084, 4,886,191 and 5,779,155. The disclosure of these patents, and the priority application referred to above, are incorporated herein by reference as if fully set forth herein. 
   Another concern is that while an adult will typically prefer an over cap and valve for an aerosol can that is intuitive in its operation and relatively easy to use, this may not be optimal in all cases. For example, aerosol cans that are too easy to trigger may lead to accidental or unauthorized discharge. Balancing the need for easy operation with the desire for control over use can be challenging, particularly when a remote triggering system, or an aerosol over cap, activates the aerosol can. 
   A particular problem when using a remote triggering system is the reliance aerosol cans typically have-on protruding valve stems. Such stems can suffer from reliability issues such as breaking off during use. Also, they can lead to undesired dispensing since they are always linked to the dispensing valve after manufacture. 
   In separate, unrelated work, Summit Packaging Systems, Inc. has developed a female valve for an aerosol container. The valve is operated by a push button having an integral downwardly projecting valve stem. While this structure has addressed some of the issues described above, to our knowledge female aerosol valves have not reliably been adapted for use with remotely triggered sprayers used for cleaning, or adapted for use with over cap actuators. 
   Thus, a need exists to provide devices which better address these concerns, particularly in the context of remotely triggered sprayers and sprayers relying on over cap actuators, while still retaining the capability of performing core dispensing functions. 
   SUMMARY OF THE INVENTION 
   In one aspect the invention provides an aerosol canister assembly for delivering a chemical from an interior cavity of a canister to a desired location. The assembly includes a canister suitable for holding a chemical mixed with a pressurized propellant gas. 
   The particular chemical to be delivered is not critical. It may be any of the known chemicals that are delivered from aerosol containers (most preferably a surfactant based cleaning chemical such as one used for floor care in the S. C. Johnson Go Mop™ system or an insecticide commonly delivered by aerosol spray). 
   Similarly, the propellant gas is not critical. It may be any of the known propellant gasses commonly used with aerosol containers. Particularly preferred propellant gasses are hydrocarbon propellants such as propane, butane, isopropane, isobutane, and mixes thereof, but many other propellant gasses may be used. 
   In accordance with the invention, the canister has a valve with an open (typically upwardly open) female cavity. The valve is suitable for controlling the delivery of the chemical from the canister to the outside of the canister when the chemical is positioned in the canister with the propellant gas. An over cap is positionable on the canister over the valve, the actuator having a nozzle opening and being linked to a valve stem. 
   When the valve stem is inserted into the female cavity by axial (typically axially downward) relative movement there between, the valve stem defines a pathway for expelling the chemical. The chemical passes through the valve, through the valve stem, and from the nozzle opening. The nozzle opening may be a radial or axial opening. 
   The valve stem is either an integral part of the over cap or removably connected to the over cap. In the latter case the over cap has a stem socket in communication with the nozzle opening, the stem socket being sized to receive the valve stem. It opens to an interior defined by a cylindrical wall extending to one side of a top wall of the over cap. 
   In a most preferred form the over cap has a radially peripheral wall to which is hinged a lever arm suitable for mounting the valve stem for displacement of the valve. The lever arm includes the nozzle opening and defines a stem socket sized to receive the valve stem. 
   In another aspect the invention provides a cleaning device. It has a cleaning head, a housing connected to the cleaning head for retaining a spray canister, and a shaft connected to the housing at one end and mounting a handle at an opposite end, the handle having a trigger. 
   There is also an aerosol canister assembly for delivering a chemical from an interior cavity of a canister to a desired location adjacent the cleaning head. That assembly has a canister suitable for holding a chemical mixed with a pressurized propellant gas, the canister having a valve with an axially open female cavity. The valve is suitable for controlling the delivery of the chemical from the canister to the outside of the canister when the chemical is positioned in the canister with the propellant gas. 
   There is also in the canister assembly an actuator positionable on the canister adjacent the valve, the actuator having a nozzle opening and being linked to a valve stem. The valve stem is insertable into the female cavity by axial relative movement there between, the valve stem defining a pathway for expelling the chemical in the canister from the nozzle opening when the valve is opened by the valve stem. 
   The cleaning device also has an initiator assembly causing movement of the trigger to move a portion of the actuator when the chemical is to be dispensed. Hence, the cleaning chemical can be sprayed by a remote spraying apparatus. 
   In preferred forms of the cleaning device, the shaft is hollow and the initiator assembly includes a core slidable in the shaft and a rod disposed in the housing in contact with a pivot link pivotally attached to the housing and coupled to the slidable core. The trigger is actuated to slide the slidable core, which in turn pivots the pivot link and brings the rod into contact with the actuator. Also, the rod and the slidable core move in substantially opposite directions. 
   In another preferred form of the cleaning device, the housing includes an alignment protrusion and the actuator is in the form of an over cap having a top wall defining a recess sized to receive the alignment protrusion such that the over cap is received in the housing in a correct orientation. In this embodiment the valve stem defines a passageway in communication with a spray nozzle adapted to provide a fan-shaped spray. 
   In another aspect of the cleaning device, the actuator can be in the form of a button having a valve stem either integrally formed therewith or removably connected to the button. 
   It will be appreciated that the present invention improves aerosol canisters and their triggering systems, particularly those that are well suited for remote triggering or use with over caps. When the actuator is separate from the canister (e.g. during manufacturing, shipment or storage) the canister cannot be easily activated. Hence, the product is less likely to be accidentally discharged, or discharged by those not authorized to use the product at such times. 
   Further, should a valve stem break off, it can readily be removed from the canister, with the canister then being activated by a replacement actuator. This minimizes consumer dissatisfaction should a remote triggering apparatus cause a stem to break off in a conventional can. 
   The foregoing and other advantages of the present invention will appear from the following description. In the description reference is made to preferred embodiments of the invention. These embodiments do not represent the full scope of the invention. Rather, reference should therefore be made to the claims herein for interpreting the full scope of the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows a perspective view of a mop having a trigger-actuated spray canister according to this invention; 
       FIG. 2  shows an exploded perspective view of a housing for use with this invention; 
       FIG. 3  shows a top plan view of an over cap of this invention; 
       FIG. 4  shows a perspective view of an underside of the over cap according to this invention; 
       FIG. 5  shows a sectional view, in assembled form, taken along the line  5 — 5  in  FIG. 2  when the over cap is placed in the housing; 
       FIG. 6  shows a sectional view along the line  6 — 6  in  FIG. 3 ; 
       FIG. 7  is a detailed view of area A in  FIG. 6 ; 
       FIG. 8  is a partial sectional view taken along lines  8 — 8  in  FIG. 3 , showing a nozzle; 
       FIG. 9  is a sectional view of the housing of this invention holding the canister; 
       FIG. 10  is an exploded perspective view of a lower end of a shaft assembly of this invention; 
       FIG. 11  is an exploded perspective view of an upper end of a shaft assembly and a handle of this invention; 
       FIG. 12  is a partial perspective view depicting an alternative embodiment of a cleanser containing canister having a female valve for use with the above assembly, with an actuator rod shown in partial phantom; 
       FIG. 13  is a partial cross-sectional view taken along line  13 — 13  of  FIG. 12 , through an over cap of the present invention when used in the above assembly; 
       FIG. 14  is a partial sectional view of an alternate embodiment of the over cap having a unitary valve stem; 
       FIG. 15  is a view similar to  FIG. 14 , but of another embodiment of the over cap having a separable valve stem; and 
       FIG. 16  is a view similar to  FIG. 14 , but of yet another embodiment of the invention in which a button actuator having a valve stem takes the place of an over cap. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIGS. 1-12  show a mop of the present invention which has an upper trigger that can be used to remotely activate a lower aerosol canister to thereby spray a cleaning chemical adjacent a mop head. Apart from the actuator/valve interface, the structure and operation of this system was described in somewhat greater detail in the priority application (U.S. Ser. No. 09/951,632, filed Sep. 14, 2001, now allowed). 
     FIG. 1  shows the invention according to a preferred embodiment. A trigger-actuated mop  1  comprises a mop head  100 , a housing  200 , a shaft assembly  300 , and a handle  400 . The mop head  100  holds a cleaning device such as, by way of non-limiting example, a sponge or disposable/replaceable cloth. The housing  200  connects to the mop head  100  by way of a U-shaped hinge  202 , which engages a protrusion and a ball joint on the mop head  100 . 
   As shown in  FIG. 2 , the housing  200  is comprised of a front panel  204  and a rear panel  206  held together preferably by screws (not shown). Each of the panels  204 ,  206  includes a half-cylinder at its top (or proximal end), so that when the two panels  204 ,  206  are joined, a guide hole  217  results. However, the half cylinders do not meet, leaving a slot in the guide hole  217 . A collar  219  slides into the guide hole  217  and two fins  221  of the collar  219  slide into the slots. 
   Preferably, the collar  219  and panels  204 ,  206  are joined together by screws. Other means of joining the panels and collar are also possible, such as adhesive, plastic fasteners, and the like. Moreover, the housing  200  may be joined to the mop head  100  by a variety of means, including but not limited to a ball joint, a multi-axis hinge joint, a single-axis hinge joint, a fixed connection, a flexible member, or the like. 
   The panels  204 ,  206  define a space into which an actuator rod  208  is slidably mounted. The actuator rod  208  is preferably slidably supported on two protrusions  210 , but more or fewer than two may also be provided. Also, an actuator rod guiding portion (not shown), such as a groove, may be formed in one or more of the protrusions to aid in guiding the actuator rod  208  during its movement. The bottom end  212  of the actuator rod  208  is bent in a J-shape and includes a flattened portion  240 , which supports a washer  228 , while the top end  214  is bent at an angle, preferably a right angle, to contact a pivot link  216 . 
   The flattened portion  240  of the actuator rod  208  acts as a stop for the washer  228 . That is, the washer  228  may only slide onto the actuator rod  208  up to the flattened portion  240 . Of course, other stops may be used to position the washer  228  such as, by way of non-limiting examples, a dimple or bead formed on the actuator rod  208 , or a reduced cross-section portion on the actuator rod  208  used in conjunction with a washer having a cross-section so as to mate with that reduced cross-section of the actuator rod  208 . 
   The bottom end  212  of the actuator rod  208  protrudes through an aperture  213  in the front panel  204  to contact an over cap  500  on a canister  5 , which is preferably a spray canister such as, for example, of the aerosol type. The washer  228  acts as a base for a spring  230 , which biases the actuator rod  208  downwards, away from the over cap  500 . 
     FIG. 3  shows the over cap  500 , which generally comprises a top surface  502 , a nozzle  503 , a cylindrical wall  504  depending from the top surface  502 , a lever arm  508  and an actuator port  505 . The actuator port  505  is adapted to receive a terminal end of the bottom end  212  of the actuator rod  208 , so that the actuator rod  208  can contact the lever arm  508  at a pad  509 . 
     FIG. 3  further shows the top surface  502  including a D-shaped recess  506 . The D-shaped recess  506  ensures that the over cap  500  is always correctly oriented in the housing  200 . As shown in  FIG. 5 , the housing  200  includes an aligning protrusion  232  for mating with, or receiving there over, the walls of the D-shaped recess  506 . In this way, the orientation of the over cap  500  is assured. Of course, the D-shaped recess  506  and the aligning protrusion  232  may take on a variety of shapes, and need not be exactly as illustrated. For example, a plurality of holes and posts may be used. 
   As shown in  FIG. 6 , the lever arm  508  substantially traverses the diameter of the top surface  502 , and is attached to the cylindrical wall  504  at a pivot point  520 , which is positioned at an end opposite from the D-shaped recess  506 . The pivoting lever arm  508  is separated from the top surface  502  and the D-shaped recess  506 . As shown in  FIGS. 3 and 4 , the lever arm  508  terminates in the D-shaped recess  506 , and is not connected to a floor  507  of the D-shaped recess  506 . As such, the pivoting lever arm  508  is free to move out of the plane of the floor  507  of the D-shaped recess  506 . A thickness of the lever arm  508  is thinned at the pivot point  520 , as shown in  FIG. 6 , to reduce the force required to pivot the lever arm  508  about the pivot point  520 . 
   Preferably, the lever arm  508  is disposed below the top surface  502  to minimize the risk of unknowing or accidental movement of the lever arm  508 , but it may be on the same level as or above the top surface as well. In addition, the lever arm  508  preferably has ribs  560  on its underside to increase its rigidity, as shown in FIG.  4 . 
   As shown in  FIG. 4 , the interior surface of the cylindrical wall  504  has a plurality of ribs  516  at its base. These ribs  516  engage a rim on the canister  5 , holding the over cap  500  securely to the canister  5 . Of course, alternative means to secure the over cap  500  to the canister  5  may be used, such as adhesive, or even integrally forming the over cap  500  with the canister  5 . 
   Viewing the over cap  500  as depicted in  FIG. 3 , it is clear that one of the advantages of the over cap  500  is that it cannot be easily actuated by children. Even if a child could remove the canister  5  from the housing  200 , the child would have difficulty pressing on the lever arm  508  in an unknowing attempt to cause the canister  5  to expel its contents, since the lever arm  508  presents no easily-accessible grip or button with which to actuate the canister  5 . 
   As shown in  FIGS. 7  (a detailed view of area A of  FIG. 6 ) and  8  (a partial sectional view taken along line  8 — 8  of FIG.  3 ), the nozzle  503  of the over cap  500  is adapted to provide a fan-shaped spray at a predetermined angle as measured from the top surface  502 . This angle may be between 40° and 90°, preferably between 70° and 85°, and more preferably 78.5°. An opening  510  is tilted with respect to the top surface  502  to achieve the angled spray, as evident in FIG.  7 . 
   To achieve a fan-shaped spray, the opening  510  is wider in a first direction than it is in a second direction, where the first direction is substantially orthogonal to the second direction. In particular, the width x of the opening  510  shown in  FIG. 7  is greater than the width y shown in FIG.  8 . This results in a spray that is wider in a direction perpendicular to a length of the lever arm  508  than in a direction parallel with the length of the lever arm  508 . Of course, the spray may be rotated in any direction so that its width points in any direction without departing from the scope of the invention. 
   As shown in  FIG. 7 , the end of the nozzle  503  nearest the canister  5 , which makes up a stem socket, comprises a chamfered opening  514  leading into a tilted undercut  517 . A cylindrical cavity  518 , which is integral with and beyond the undercut  517  of the stem socket, is configured so as to have an inner diameter smaller than an outer diameter of the valve stem  7  of the canister  5 , thus acting as a stop for the valve stem  7  and preventing the valve stem  7  from entering the cylindrical cavity  518 . 
   The tilted undercut  517  is preferably tilted at an angle of about 5°, although other angles may also be used, to effect a sealing engagement between the tilted undercut  517  and a top portion of the valve stem  7  when the lever arm  508  is actuated, i.e., depressed downward relative to the top surface  502 . 
   As illustrated in  FIGS. 2 ,  5 , and  9 , the housing  200  retains the canister  5 /over cap  500  assembly using a retainer  218  and the aligning protrusion  232 . The aligning protrusion  232  acts not only to provide for a proper orientation of the over cap  500 , but also acts as a support, e.g., a “pin-like” support, to retain the over cap end of the canister  5 /over cap  500  assembly in the housing  200 . The canister end of the canister  5 /over cap  500  assembly is retained in the housing  200  by the retainer  218 . 
   The retainer  218  is spring-biased against the canister  5  by a spring  220  and retains the canister  5  by a friction force between the retainer  218  and the canister bottom. In addition, the retainer  218  includes a lip  222  along its outer periphery, as shown in  FIG. 2 , that contacts an outer surface of the canister  5  and prevents the canister  5 /over cap  500  assembly from dislodging or “falling out” of the housing  200 . 
   The retainer  218  further includes an abutment  224  protruding from a surface of the retainer  218 , which contacts a bottom surface of the canister  5  to also prevent the canister  5 /over cap  500  assembly from freely releasing or “falling out” of the housing  200 . As shown in  FIG. 9 , the retainer  218  preferably includes a tongue or handle  226 , so that the retainer  218  can be easily biased against the spring  220  by a user to remove the canister  5  from the housing  200 . 
   To install the canister  5 /over cap  500  assembly into the housing  200 , a user first inserts the over cap end of the canister  5 /over cap  500  assembly into the housing  200 , causing the D-shaped recess  506  to matingly receive the aligning protrusion  232 . In this position, the D-shaped recess  506  of the over cap  500  rests on the aligning protrusion  232 . Then, the user presses the canister end of the canister  5 /over cap  500  assembly into the housing  200  until the retainer  218  fittingly engages the canister end of the canister  5 /over cap  500  assembly. 
   Alternative means for holding the canister end of the canister  5 /over cap  500  assembly are also contemplated, and the retainer  218  may be omitted without departing from the scope of the invention. For example, a clip may be integrally formed in the front panel  204 , allowing the canister  5  to snap into the housing  200 . In addition, an elastic strap may hold the canister  5  to the housing  200 . Variations of the retainer  218  as shown may also be used, such as a retainer  218  without any or all of the abutment  224 , handle  226 , and lip  222 . 
   Referring next to  FIGS. 10 and 11 , the shaft assembly  300  connects, preferably in a removable manner, to the collar  219  of the housing  200 , as discussed below, and comprises a lower hollow shaft  302  into which a slidable lower core  304  fits and an upper hollow shaft  303  into which a slidable upper core  305  fits. The lower core  304  has a plurality of flanges  306 , which keep the lower core  304  centered in the lower hollow shaft  302 . 
   A housing plug  308  is provided at the end of the lower hollow shaft  302  nearest the housing  200 , and is engaged with that end of the lower hollow shaft  302 . Such engagement may be effected, by way of non-limiting examples, through a friction fit, an adhesive bond, a bond formed by thermal or ultrasonic fusion, pins, screws, crimping, or the like. 
   At a distal end of the lower hollow shaft  302 , furthest from the housing  200 , is a female plug  307 . The female plug  307  is also engaged, in a manner as described above with respect to the housing plug  308 , with the lower hollow shaft  302 . A spring  310  between one of the plurality of flanges  306  and the housing plug  308  keeps the lower core  304  biased away from the housing plug  308 . 
   As indicated in  FIG. 11 , the upper hollow shaft  303  houses an upper core  305  slidably disposed therein. The upper core  305 , similarly to the lower core  304 , has a plurality of flanges  320 . A connecting plug  318  is engaged, in a manner as described above with respect to the housing plug  308 , with the upper hollow shaft  303  at a connecting end of the upper hollow shaft  303  (that is, the end nearest the lower hollow shaft  302 ). 
   The housing plug  308  and the connecting plug  318  each comprises a plurality of rings joined by longitudinal ribs, and is generally divided by a large ring  309  into an upper half  312  and a lower half  314 . The upper half  312  of each of the housing plug  308  and connecting plug  318  is shaped and sized to fit snugly into each of the lower hollow shaft  302  and the upper hollow shaft  303 , respectively. 
   The lower half  314  has a bullet-shaped cross section (i.e., one flat side), ensuring that the housing plug  308  can only be inserted on one way into either the collar  219  of the housing  200  or the female plug  307 . Each plug  308 ,  318  has a continuous, circular cavity formed there through, which is shaped to permit passage of the appropriate core  304 ,  305 . The housing plug  308  and connecting plug  318  are preferably shaped slightly differently, so that the connecting plug  318  and the upper hollow shaft  303  cannot be mistakenly inserted into the housing  200 . 
   Preferably, the lower half  314  of each plug  308 ,  318  has a ramped key  316 , which snaps into a recess, indentation, notch, window, or the like formed in an interior wall of the collar  219  (in the case of the housing plug  308 ) or of the female plug  307  (in the case of the connecting plug  318 ). The window and ramped key mechanism secures, either permanently or removably, the housing plug  308  to the housing  200  and the connecting plug  318  to the lower hollow shaft  302 . 
   In one example, the ramped key  316  providing for the permanent connection is a flexible, wing-like protrusion having a terminal end that flexes inwardly upon insertion into either the collar  219  or the female plug  307 . The wing-like protrusion remains inwardly flexed until reaching the window, at which point the terminal end of the wing-like protrusion extends into the window, thereby creating the permanent connection. 
   The ramped key  316  providing for the removable connection can be a wing-like protrusion having an outwardly ramped surface integral with an inwardly ramped surface, where a peak is formed there between (e.g., a protrusion similar in shape to the standard keyboard character “&gt;”). Upon insertion into either the collar  219  or the female plug  307 , this wing-like protrusion remains inwardly flexed until reaching the window, at which point the peak of the wing-like protrusion extends into the window. 
   This wing-like protrusion is rendered removable by the inwardly ramped surface, which, upon exerting a force to withdraw the lower half  314  from the collar  219  or the female plug  307 , causes the wing-like protrusion to once again inwardly flex, thereby extracting the peak from the window and allowing for removal. Of course, other means of permanently or removably attaching the lower half  314  to the collar  219  or the female plug  307  may be used such as, by way of non-limiting example, fixed pins, screws, clamps, spring-loaded pins, bolts, twist-and-lock connections, and the like. 
   As with the lower core  304 , a spring  322  biases the upper core  305  away from the connecting plug  318  by pressing against one of the flanges  320 , as shown in FIG.  11 . An actuating block  324  is preferably attached to the upper core  305  at the grip, or distal, end of the upper core  305 . Of course, the manner of attachment may include any of those discussed above with regard to the housing plug  308 . 
   As shown in  FIG. 11 , a grip end of the upper hollow shaft  303  includes a plurality of holes  326  there through. In addition, the upper hollow shaft  303  has a top cutout  328  and a bottom cutout  330  (where the top and bottom are defined with regard to the location of the holes  326 , which defines the sides). Of course, the term “cutout” does not implicate a method of forming the cutouts, as the cutouts  328 ,  330  may be formed by removing material or molding the upper hollow shaft  303  with the cutouts  328 ,  330  formed therein. Rather, the term refers to the space in the upper hollow shaft  303 . 
     FIG. 11  shows a handle  400  comprised of a right panel  402  and a left panel  404 . Each of the right panel  402  and the left panel  404  preferably includes three protrusions  406  (two of which are long enough to extend through the holes  326  in the upper hollow shaft  303  and contact each other). The right panel  402  and the left panel  404  are secured together by screws passing through the protrusions  406  of one of the panels  402 ,  404  and into the protrusions  406  of the other panel  402 ,  404 . Of course, other means to hold the right panel  402  and the left panel  404  together may be used such as, by way of non-limiting example, bolts, pressure-fit pins, adhesive, and the like, and more or fewer than three protrusions and holes may be provided. Moreover, although only a right and left panel are described, a grip insert  405 , preferably formed of a soft material, may also be provided. 
   Each of the right and left panels  402 ,  404  includes a curved portion so that when the panels  402 ,  404  are secured together by the screws to form the handle  400 , a trigger opening  410  on the bottom is formed. The trigger opening  410  receives a trigger  412  there through. The trigger  412  is pivotally held in position by a pin (not shown), which passes either through or into panels  402 ,  404  and through a hole in the trigger  412 . 
   Of course, other means for pivotally supporting the trigger  412  may be used such as, by way of non-limiting example, a bolt, a screw, a hollow tube, and the like. The trigger  412  includes a U-shaped extension or lip  416 , a front face  418  of which is rectangular and has side rails  420 . The rectangular front face  418  contacts the actuating block  324 , and the rails  420  prevent the actuating block  324  from moving laterally. Of course, the rails need not be provided, and the front face  418  need not be rectangular. Further, any means of transforming a pivoting action into a linear action is acceptable, such as a cam and follower or a rack gear. 
   Each of the panels  402 ,  404  also includes a curved portion in its top, so that when the panels  402 ,  404  are secured together, a lock opening  414  is formed. The lock opening  414  receives a trigger lock  415 , and includes ribs (not shown) for guiding the trigger lock  415 . The trigger lock  415  includes a horizontal plate  422  and a vertical switch  424 , as shown in FIG.  11 . The vertical switch  424  protrudes out of the lock opening  414  above an outer surface of the handle  400 , so that a user can contact the vertical switch  424  with a finger, and extends below the horizontal plate  422  into the upper hollow shaft  303 . The horizontal plate  422  slides along an axis parallel to a longitudinal axis of the upper hollow shaft  303 , and is guided during such sliding motion by the ribs. 
   When a user pushes against or pulls on the vertical switch  424 , the horizontal plate  422  slides along the upper hollow shaft  303  and within the ribs of the handle  400 . In a locked position, the trigger lock  415  is in its most forward position, towards the mop head  100 . In an unlocked position, the trigger lock  415  is in its most rearward position, furthest from the mop head  100 . In the locked position, the vertical switch  424  contacts, or nearly contacts, the trigger  412 . As such, when a user attempts to squeeze the trigger  412 , a top of the trigger  412  contacts the vertical switch  424 , preventing further movement of the trigger  412 . 
   An advantage of the cleaning device of this invention is its modular construction. The mop head  100 , the housing  200  and the shaft assembly  300  may all be separate pieces that can be packaged separately and compactly. In the preferred embodiment, the shaft assembly  300  can be packaged in two parts, i.e., the lower hollow shaft  302  and the upper hollow shaft  303 . Each of the lower hollow shaft  302  and the upper hollow shaft  303  is preferably packaged to include the plugs  308 ,  318 , springs  310 ,  322  and inner cores  304 ,  305 . 
   The lower hollow shaft  302  preferably has the female plug  307  attached to its distal end, and the upper hollow shaft  303  preferably has the handle  400  attached to its distal end. Likewise, the housing  200  can be packaged as a complete unit to include the actuator rod  208 , washer  228 , spring  230 , pivot link  216  and retainer  218 . As such, when a user removes the cleaning device  1  from the package, the user simply snaps the lower hollow shaft  302  to the housing  200  and the upper hollow shaft  303  to the lower hollow shaft  302 . 
   In operation, a user generally utilizes the trigger-actuated mop like any conventional mop. However, when the user desires to apply the contents of the container  5  (e.g., cleaning fluid) to the surface being cleaned, the user simply squeezes the trigger  412 . At this time, the trigger  412  pivots causing the lip  416  to press against the actuating block  324 , which moves the upper core  305  downward toward the mop head  100 . The upper core  305  moves through the circular cavity in the connecting plug  318  past the female plug  307  and contacts the lower core  304 . 
   As a result, the lower core  304  slides through the housing plug  308  and into the housing  200 . The bottom of the lower core  304  contacts the pivot link  216 , causing the pivot link  216  to rotate, thereby moving the actuator rod  208  in an actuating direction toward the proximal end (i.e., in a direction substantially opposite to the sliding direction of the lower core  304 ). The terminal end of the bottom end  212  of the actuator rod  208  slides up through the aperture  213  in the front panel  204  and contacts the pad  509  of the lever arm  508  of the over cap  500 . 
   The lever arm  508  pivots toward the valve stem  7  on the canister  5 , and the shoulder formed at the top of the cylindrical cavity  518  in the stem socket presses on the valve stem  7 , opening a valve (not shown) in the canister  5  to allow projection of the contents of the canister  5  through the nozzle  503  and onto the surface to be cleaned. When the trigger  412  is released, the springs  310 ,  322  in the hollow shafts  302 ,  303 , respectively, bias the cores  304 ,  305 , respectively, upwards against the trigger  412 , causing the trigger  412  to pivot back into its original, non-activated position. This action relieves the force on the actuator rod  208  and allows the spring  230  to bias the actuator rod  208  away from the over cap  500 . A spring (not shown) in the valve in the canister  5  returns the valve stem  7  back to its original position, closing the valve and stopping the contents of the canister  5  from exiting the canister  5 . 
   The components of this invention, such as the mop head  100 , housing  200 , shaft assembly  300 , handle  400 , and over cap  500 , are preferably molded from plastic, such as ABS resin for its glossiness and strength. However, these molded components may also preferably be made from polypropylene, for its low cost. 
   Particularly in accordance with the additional disclosure of this application relative to the priority case, the inventors propose the improved canister assembly concepts of  FIGS. 12-16 . These all rely on the canister itself being provided with a female valve at its upper end that is activated by a separate/removable valve stem associated with an actuator (e.g., the over cap lever of  FIG. 13 , the over cap integral stem of  FIG. 14 , the over cap separable, valve stem of  FIG. 15 , and the button actuator of FIG.  16 . 
     FIGS. 12 and 13  depict a canister  5 ′ and an over cap  500 ′ very similar to those described above except for that the canister  5 ′ has a female valve assembly and the over cap  500 ′ has include a male valve stem. Canister  5 ′ is suitable for use with the above assembly (identical in overall size and configuration) and the three additional embodiments of the invention shown in  FIGS. 14-16 . The over cap  500 ′ as shown in  FIGS. 12 and 13  is somewhat relevant to the unitary valve stem embodiment of FIG.  14  and the separate valve stem embodiment of FIG.  15 . The over cap  500 ′ is not required for the button actuator embodiment of FIG.  16 . 
   Referring to  FIGS. 12 and 13 , the over cap  500 ′ has a top surface  502 ′, a nozzle  503 ′, a cylindrical wall  504 ′ depending from the top surface  502 ′, a lever arm  508 ′ and a D-shaped recess  506 ′ with a notch  505 ′. The D-shaped recess  506 ′ ensures that the over cap  500 ′ is always correctly oriented in the housing  200 ′ by receiving the aligning protrusion  232  as discussed above and shown in FIG.  5 . 
   As before, the lever arm  508 ′ substantially traverses the diameter of the top surface  502 ′, and is hinged to the cylindrical wall  504 ′ at a pivot point  520 ′ opposite from the D-shaped recess  506 ′ so that it is free to move out of the plane of a floor  507 ′ of the D-shaped recess  506 ′. Again as before, a thickness of the lever arm  508 ′ is thinned at the pivot point  520 ′ to reduce the force required for actuation. 
   The nozzle  503 ′ of the over cap  500 ′ is adapted to provide a fan-shaped spray at a predetermined angle as measured from the top surface  502 ′, preferably ranging between 40° and 90°, more preferably between 70° and 85°, and even more preferably 78.5°. An opening  510 ′ is tilted with respect to the top surface  502 ′ to achieve the angled spray. The fan-shaped spray is achieved in the same manner as above by making the opening  510 ′ wider in a first direction than it is in an orthogonal second direction (see FIG.  8 ). 
   Referring now to  FIG. 14 , an end of the nozzle  503 ′ nearest the canister  5 ′ forms an elongated, generally tubular integral valve stem  600 . In the over cap embodiment of  FIG. 15 , the end of the nozzle  503 ′ nearest the canister  5 ′ makes up a stem socket  700  tapering inward to an cylindrical inner diameter  702  sized only slightly larger than a separate tubular valve stem  704  to receive it in a tight fit. The valve stem either unitary  600  or separable  704  interfaces with an orifice  800  in a female valve  802  of the canister  5 ′ to spray contents of the canister  5 ′ through the nozzle  503 ′ when the lever arm  508 ′ is depressed. 
   The female valve  802  is of a known construction for aerosol canisters. The valve  802  has an outer valve cup  804  defining the orifice  800  and capping the end of the canister  5 ′, a gasket (not shown) may provided at this the valve cup/canister interface for better sealing. Below the valve cup  804  is a gasket  806  around the valve stem and between the valve cup  804  and a cylindrical valve housing  808 . 
   The valve housing  808  has an open upper end and a hose barb type lower end  810  for attaching a dip tube (not shown) extending down near the bottom of the canister  5 ′. The valve housing  808  also has a flanged upper end that is captured by a crimp in the hub of the valve cup  804  to secure it in place. The valve housing  808  supports a spring  814  and a stem cup  816 . The stem cup  816  has a lower end around which the spring  814  fits and an open upper end defining a circular groove receiving the bottom of the valve stem tightly. The outer diameter of this upper end of the stem cup  816  is slightly smaller than the inner diameter of the valve housing  808  to define an annular flow channel  820  there between. 
   Before the valve  802  is actuated, the pressurized contents of the canister  5 ′ are prevented from escaping by the seal created between the gasket  806  and the top of the stem cup  816 . However, when the valve stem pushes the stem cup  816  downward, this seal is broken allowing some of the pressurized contents to pass through the annular flow channel  820  to an opening  822  near the bottom of the valve stem which is in communication with the nozzle  503 ′. Removing the downward force on the valve stem allows the spring  814  to reseat the stem cup  816  against the gasket  806 , thereby restoring the seal. 
   The operation of the assembly with the two alternate over cap embodiments of  FIGS. 14 and 15  is identical to that described above. Briefly (with additional reference to  FIGS. 1 ,  2 ,  10  and  11 ), the user simply squeezes the trigger  412 , which causes the lip  416  to press against the actuating block  324 , which moves the upper core  305  downward toward the mop head  100 , which in turn moves through the circular cavity in the connecting plug  318  past the female plug  307  and contacts the lower core  304 . As a result, the lower core  304  slides through the housing plug  308  and into the housing  200 . 
   The bottom of the lower core  304  contacts the pivot link  216 , causing the pivot link  216  to rotate, thereby moving the actuator rod  208  in an actuating direction to contacts the pad  509 ′ of the lever arm  508 ′. The lever arm  508 ′ pivots toward the canister  5 ′, which in turn causes the valve stem to unseat the stem cup  816  to allow projection of the contents of the canister  5 ′ through the nozzle  503 ′ and onto the surface to be cleaned. When the trigger  412  is released, the springs  310 ,  322  in the hollow shafts  302 ,  303 , respectively, bias the cores  304 ,  305 , respectively, upwards against the trigger  412 , causing the trigger  412  to pivot back into its original, non-activated position. This action relieves the force on the actuator rod  208  and allows the spring  230  to bias the actuator rod  208  away from the over cap  500 ′. The valve spring  814  returns the valve stem back to its original position, closing the valve and stopping the contents of the canister  5 ′ from exiting the canister  5 ′. 
   The alternate embodiment of  FIG. 16  replacing the over cap with a button actuator  900  operates in the same manner except that the actuator rod  208  contacts the top end of the button actuator  900  directly rather than an intermediate pivotal member of an over cap. The button actuator  900  can be of a conventional construction provided it has a male valve stem  902  defining a passage  904  from a lower opening  906  to a nozzle  908 , which preferably provides a wide spray pattern at an oblique angle to the canister  5 ′, as described above. 
   The preceding description is merely of preferred embodiments of the invention. One skilled in the art will readily apprehend alternative embodiments that nevertheless fall within the scope and breadth of the invention. For example, an embodiment of the invention in which an over cap with a pivoting lever arm that contacts and operates a separate stemmed button actuator, while not described in detail herein, is also within the scope of the present invention. Thus, the claims should be looked to in order to understand the full scope of the invention. 
   INDUSTRIAL APPLICABILITY 
   Disclosed are devices for facilitating the cleaning of hard surfaces such as floors and walls, and aerosol canisters suitable for supplying cleaning materials for use therewith.