Patent Publication Number: US-6209184-B1

Title: Liquid soap dispenser

Description:
This is application is a division of application Ser. No. 08/512,227, filed Aug. 7, 1995, now U.S. Pat. No. 5,992,698. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to apparatus for dispensing liquid soap, normally in discrete small quantities. Such a dispensing apparatus is used, particularly for hygienic purposes, in public or institutional washrooms or wherever there are a relatively large number of different users. 
     BACKGROUND OF THE INVENTION 
     In restrooms, workshops, laboratories, hospitals and similar places, there are many individuals who require access to cleaning soap. Providing soap and detergent bars for multiple use poses a problem because some individuals dislike using a soap bar which had been used before by a person who may have left a wet, soggy soap bar. To obviate this problem to a degree, powdered soap dispensers have been provided. However, the dispensing of powders and pastes, if very viscous, is at an extremely slow rate, if at all. Also, powdered soap may cake in the hands and require vigorous rubbing with water before it becomes solubilized and loses its grittiness. 
     Liquid soaps therefore have certain advantages over soap bars and powdered soap, because the liquid soap is already partially emulsified in a diluent resulting in quick further dispersal. Liquid soap dispensers are well known and have been used and widely installed in lavatories in public places, such as restaurants, schools, hospitals, trains, etc. 
     Prior art devices for dispensing liquid soap usually have a reservoir that must be filled from a larger supply container. The filling operation tends to be time-consuming and messy. Such dispensers are usually mounted to a wall, making some parts difficult to service or replace. Also, it is often difficult to feed the product directly into the dispenser container by pouring the liquid from a big supply tank because the dispenser is so close to the wall. 
     Furthermore, prior dispensers have been of relatively complex construction, frequently using a large number of parts, the assembly of which entails substantial labor. For example, some dispensers employ a complex pressuring system to dispense the soap. These devices result in mechanical difficulties and are subject to undue wear and fairly rapid breakdown. Some difficulties may also arise when screws must be loosened for the replacement of parts, particularly the dispensing nozzle or cartridge pump, which may become rusted and/or encrusted with the soap. 
     Liquid soap dispensers which are installed in restrooms, washrooms and the like are subject to damage by vandals. It therefore becomes necessary for the dispensers to be repaired or replaced on a periodic basis. When several dispensers must be replaced periodically, it results in a significant expense and inconvenience. 
     In some situations, it is necessary to make sure that a certain type of product is dispensed from a certain dispensing apparatus. For example, a plurality of dispensers may be used in a hospital for dispensing different types of soap or lotion products, or a restaurant may employ a plurality of dispensers for several types of condiments. Another example is a situation in which a company has installed a relatively expensive and durable dispensing device which is intended for use with a high quality soap product, and the company wishes to prevent use of the dispenser with a lower quality soap product. With prior dispensers, there has been no mechanism to prevent the dispensing device from being filled with the improper type of product, when the dispensing device is meant to be dedicated to a certain type of product. 
     Some prior soap dispensers utilize a container or cartridge of liquid soap which is removably mounted on a dispensing apparatus so that it can be replaced by another cartridge when it is empty. However, the soap containers for some such dispensers are of the refillable type. This means that the spent containers must be collected, sterilized, refilled and sealed for reuse, which is a time-consuming and expensive operation. Because the container is refillable, the refill opening is accessible to users. This could result in contamination of the contents or refilling with soap from an unauthorized source. 
     In some dispensers, the container is readily removable from the dispenser by any user, so that the entire container could easily be replaced by a “bootleg” container. To avoid this problem, some dispensers are provided with closed, lockable cabinets for enclosing the refill cartridge or container, so as to prevent access by unauthorized persons. But this type of housing is relatively expensive. Furthermore, such prior dispensers have had a relatively complex construction, frequently using a large number of parts, the assembly of which entails substantial labor. 
     The prior art dispensers have exhibited one or more other disadvantages. Such disadvantages include the need for substantial pressure to expel the liquid, difficulty in replacing the liquid reservoir, liquid dripping, the opportunity for bacterial contamination, the potential for entrapping air, difficulty in varying the volume of delivered liquid, inability to substantially empty the liquid reservoir, and the like. 
     The present invention solves many of the problems associated with currently available dispensers. 
     SUMMARY OF THE INVENTION 
     The present invention is a wall-mounted dispenser for liquid soap and the like. The dispenser has a cartridge which contains the liquid material, and the cartridge has a groove on its rear face. The dispenser also has a mounting means which features a rib which is sized and configured to correspond with the groove on the cartridge. The dispenser&#39;s cover means substantially encloses the cartridge, and is hingedly interconnected to the mounting means. In the preferred embodiment, the dispenser&#39;s mounting bracket includes a movable latch member for fixing the cartridge into place. The rib and groove of the preferred dispenser are formed by adjustable members in the mold which fabricates the mounting plate and cartridge. 
     Another aspect of the invention is a method of manufacturing a liquid soap dispenser, comprising the steps of: forming a mounting bracket in a first mold, the mold having an adjustable insert for forming a rib on the mounting bracket; forming a cartridge in a second mold, the second mold having an adjustable channel for forming a groove in the cartridge; and assembling the cartridge and mounting bracket within a housing member. 
     An advantage of the dispenser is that the corresponding rib and groove of the mounting bracket and cartridge prevent the use of an improper product in the dispenser. This is because an improper or unauthorized cartridge will not fit into proper nesting position in the mounting bracket. The dispenser is designed such that the size and configuration of the ribs and grooves can be varied for different customers, and/or according to different types of soap (or other type of product) within the dispenser. For example, a hospital may need to provide an anti-microbial product for surgical areas, while a different type of soap is suitable for other areas of the hospital. Therefore, one area of the hospital would have a first type of dispenser design that would accommodate an anti-microbial product cartridge, whereas another area of the hospital would have a second type of dispenser design that would fit the cartridge of a different type of soap. A unique design for the dispenser&#39;s mold and the cartridge&#39;s mold facilitate the manufacture of dispensers and cartridges having different designs, in order to ensure that each dispenser is fitted with a cartridge containing the proper product. 
     Another advantage of the dispenser is that it is inexpensive to manufacture and durable. The dispenser can be made of inexpensive molded plastic parts with no hand machining and with no metal parts. The dispenser can be readily and easily assembled using molded parts and employing relatively unskilled labor. Therefore, the dispenser is relatively inexpensive, which is especially advantageous in the event that the dispenser is broken due to vandalism, tampering or other reasons. 
     Yet another advantage of the present invention is that the liquid dispenser can readily receive new soap cartridges. The dispenser does not require precise positioning of the cartridge so that the cartridge is in a position to dispense the liquid soap. Thus, the mounting and demounting of the cartridge is quickly and easily accomplished. The soap cartridges also eliminate the waste and spillage involved with many conventional dispensers. 
     Other features and advantages of the present invention will become apparent from the following description when taken in conjunction with the accompanying drawings. In the drawings, reference numerals indicate corresponding parts throughout the several views. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the dispenser of the present invention; 
     FIG. 2 is a side elevational view of the dispenser of the present invention; 
     FIG. 3 is an exploded, perspective view of the dispenser and cartridge; 
     FIG. 4 is a front elevational view of the back plate of the present invention; 
     FIG. 5 is a rear elevational view of the cartridge; 
     FIGS. 6A,  6 B,  6 C, and  6 D are schematic views of the cartridge&#39;s pump; 
     FIG. 7 is a perspective view of a tool assembly used in the manufacture of the dispenser; and 
     FIG. 8 is a bottom plan view of the tool assembly illustrated in FIG.  7 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to the drawings, the dispenser of the present invention is illustrated generally at  10  in FIGS. 1-3. The dispenser is intended for use with liquid soap and any other type of viscous liquid. The dispenser  10  is mounted to a vertical wall or other suitable surface. The dispenser  10  comprises a cover means or housing  12 , a cartridge  13 , a push plate  14 , and a mounting means or bracket  15 . In the preferred embodiment, each of the components  12 ,  14 ,  15  is made of a suitable plastic material and is formed by an injection molding process. A variety of plastic polymeric materials can be utilized in fabricating the housing  12  and bracket  15 , such as polypropylene, high-impact polystyrene, acrylonitrile/butadiene/styrene terpolymer (ABS), etc. A preferred plastic material is ABS. Preferably, the cartridge is made from a blow molding process and is made from high-density polypropylene. The cartridge may be made from recycled plastic resins. 
     In the preferred embodiment, the surface of the housing  12  has a sloped or rounded shape which is aesthetically attractive and easy to clean. The cover or housing  12  is preferably a single, integral member. The front portion of the housing  12  has a curved, concave portion  11 . The peripheral rim  16  of the cover  12  abuts against the wall or other surface upon which the dispenser  10  is mounted. The housing  12  and wall form a complete enclosure for the dispenser  10 , and the housing  12  has a cutout  45  to accommodate the cartridge&#39;s discharge conduit  59 . 
     The cartridge or refill bottle  13  contains the liquid soap or other product  41 . The type of product contained within the cartridge  13  may include liquid soaps, shampoos, conditioners, household detergents, cleaners, polishes, moisturizing creams, condiments, etc. The body of the cartridge  13  can be of a variety of shapes, so long as the cartridge fits properly within the dispenser housing  12 . With the illustrated design, the cartridge  13  has a top wall  18 , a bottom wall  46 , a pair of parallel side walls  45 , a front wall  80 , and a rear wall  50 . The front surface  80  of the cartridge  13  has a concave portion  17  of the same size and configuration as the concave portion  11  of the cover  12 . 
     The cartridge&#39;s rear wall  50  is flat except for one or more grooves  51  which are formed in the cartridge  13 . In the embodiment shown, the cartridge  13  has a single groove  51  which is rectangular, the longitudinal direction of which is vertical. The container  13  is relatively rigid and is preferably made of a transparent or translucent plastic material. The liquid material  41  within the cartridge  13  is preferably dyed. This allows the user to observe how full of product the cartridge  13  is. A view window (not shown) may be provided in the housing  12  to further facilitate monitoring of the amount of liquid material  41  in the cartridge  13 . Preferably, the cartridge  13  has a volume of approximately one liter. 
     In the preferred embodiment, the lower part of the cartridge&#39;s front wall has a curved portion  56 , rather than the front wall  80  and bottom wall  46  of the cartridge  13  meeting at a right angle. A dip tube  66  extends downwardly inside the cartridge  13  to withdraw the soap therefrom. The curved portion  56  of the cartridge  13  directs the soap to a portion of the cartridge  13  where it can be withdrawn by the dip tube  66 . 
     In the preferred embodiment, the bottom wall  46  of the cartridge  13  slopes slightly downwardly toward the front. Most preferably, the angle of the slope is approximately seven degrees from horizontal. Furthermore, the central portion of the cartridge&#39;s bottom wall  46  is slightly depressed with respect to the remainder of the bottom wall  46 . This forms a well where the liquid soap can collect and where the bottom of the dip tube  66  is positioned. 
     In the preferred embodiment, the upper end of the housing  12  is attached to a push plate  14 . Preferably, the push plate  14  has a pair of pins  53  which fit within opposed apertures (not shown) on the housing  12 . In order to expel the soap, the push plate  14  is suppressed by finger pressure on its upper surface. A stop member (not shown) on the housing prevents the push plate  14  from moving too far. A thumb depression  21  in the push plate  14  indicates to the user the optimal place for applying downward force on the push plate  14 . An arrow on the front edge of the push bar indicates the point from with the product will be dispensed. In certain situations such as in the health care environment, it may be desirable to depress the push plate  14  with the forearm or elbow, so that the hands do not touch the dispenser  10 . 
     The mounting bracket  15  has apertures  55  to receive screws or similar fastening means for mounting the bracket  15  on a wall. Rather than screws or fasteners, adhesive strips (not shown) could also be employed for attaching the mounting bracket  15  to the wall. 
     As shown in FIGS. 3 and 4, the mounting means  15  has a vertical plate  25 , with a plurality of forwardly displaced members  26 ,  27 ,  28  which are formed integrally with the rear plate  25 . The peripheral shape of the mounting bracket  15  corresponds to the shape of the housing  12 , so that the housing  12 , when positioned on the bracket  15 , hides the bracket  15  from view. The mounting means  15  has a bottom surface or floor for supporting the cartridge  13 . 
     A latch member  26  having a pair of flexible projections  30  is provided on the bracket  15 . The movable projections  30  are at substantially a right angle to the wall, as shown in FIG.  3 . The projections or arms  30  each terminate in a hook or detent  29 . When the housing  12  is mounted on the bracket  15 , the detents  29  engage with a pair of notches or recesses (not shown) formed within the housing  12 . The inside of the mounting bracket  15  has a pair of ramps (not shown) which are in alignment with the arms  30 . Due to the resilient nature of the arms  30 , they are deflected downwardly against the ramps when the cartridge  13  and housing  12  are being slidably engaged. When the housing  12  is in position against the bracket  15 , the detents  29  in the arms  30  spring upwardly into position to engage with the notches in the housing&#39;s ramps. 
     In the preferred embodiment, the upper portion of the mounting bracket&#39;s rim  37  has a pair of notches  31  which are sized and configured to accommodate a pair of downwardly extending members (not shown) within the housing  12 . Additionally, the bracket  15  has a foot plate  28 . The foot plate  28  has a pair of opposed apertures  54 . The apertures  54  accommodate a pair of inwardly-extending pins (not shown) within the housing  12 . In this manner, the housing  12  is hingedly interconnected to the mounting plate  15  by the foot plate  28 . In order for the housing  12  to be removed from the stationary mounting plate  15 , the user grasps the upper portion of the housing  12  and pulls the housing  12  in a direction away from the wall. When enough force is applied to the housing  12 , the hooks  29  move out of position and allow the housing  12  to be moved away from the plate  15 . The housing  12  then pivots downwardly, so as to expose the cartridge  13  and provide an access port for removing an empty cartridge  13  and replacing it with a full cartridge  13 . When the cover  12  is pivoted back into place against the plate  15 , the cover  12  completely encapsulates the mounting bracket  15  and cartridge  13 . The foot plate  28  on the bracket  15  aids in positioning the cartridge  13  properly as the housing  12  is being closed. Thus the user need not precisely position or attach the cartridge  13  in the housing  12 . 
     The mounting bracket  14  has a rib or fin  32 . Only a single rib  32  is illustrated in the embodiment shown, but a plurality of ribs  32  could be provided. The rib or lug  32  protrudes from the front projection  27  on the bracket&#39;s surface. The rib  32  is sized and configured to engage with a groove or slot  51  on the rear surface  50  of the cartridge  13 . The rib  32  is molded so as to be integral with the rest of the mounting bracket  15 . 
     Multiple dispenser configurations can be achieved by varying the angle of the rib  32 , and angle of the corresponding cartridge groove  51 . Alternatively, the size, shape and position of those components could be varied. The interface between the rib of the bracket  15  and the groove  51  of the refill bottle  13  is accomplished by a unique design of the molds which are used to form the bracket  15  and the cartridge  13 . 
     Both the rib  32  on the bracket  15  and the groove  51  on the cartridge  13  can have a variety of positions, allowing for multiple keying combinations. FIG. 7 illustrates a perspective view of the tool assembly  70  which is used in the mold for the mounting bracket  15 . The mold member  70  has a tool insert  71  which forms the rib  32  in the mounting bracket  15 . The tool insert  71  is supported by a rotatable table  74 . The table  74  rests upon a plurality of shoulder bolts  75  which are interconnected to spring pins  76 . The tool insert  71  overlies a center rotating point  72 , but one side of the tool insert  71  extends a greater distance from the center rotating point  72  than the other end of the tool insert  71 . This offset feature improves the lockout interface between the bracket  15  and the container  13 . 
     The position of the tool insert  71  is adjustable. The possible locations of the tool insert  71  are identified using a series of numbers  73 . This numbering system insures proper matching of the cartridge  13  and bracket  15  components. Although the mold pieces illustrated in FIGS. 7 and 8 are for the wall bracket  15 , the design of the mold for the bottle  13  has a similar adjustment mechanism. In the preferred embodiment, the numbers are lightly embossed on the bracket  15  and bottle  13 . With the numbering system illustrated, there are ten settings for the tool insert  71 . Each setting of the tool insert  71  is spaced approximately 36 degrees apart, and the tool insert  71  can be rotated 360 degrees. 
     At the top of each shoulder bolt  75  is a pin  77 . The underside of the table  74  has an annular track  78 . The spring-loaded pin  77  rides in the race  78 , and the race  78  has a plurality of recesses  79 . In order to adjust the position of the tool member  71 , the user simply depresses the table  74  and rotates the table  74  until the nubs  77  engage with the proper recesses  78 . This operation can be done without removing any parts from the mold and without the replacement of any parts or tool inserts, which significantly reduces cost and time expenditures. Alternative adjustment mechanisms for the tool insert  71  could be devised. For example, the mold insert  71  could be adjustable by means of bolts which are loosened to allow rotation of the mold insert  71 , with the bolts being tightened when the proper position of the mold insert is achieved. 
     For commercial reasons, if cartridges  13  containing only a certain type of liquid soap should be employed, then the cartridge  13  will have a particular configuration, and the mounting bracket  15  will have a corresponding configuration. These configurations could vary depending on the type of product being dispensed. Particular rib and groove configurations used in different settings and for different products prevent the use of unauthorized cartridges with the dispenser  10 , because an unauthorized or “bootleg” cartridge  13  would not fit into proper nesting position in the mounting bracket  15 . 
     The push plate  14  is squeezed to expel the liquid soap in the cartridge  13  directly into the user&#39;s hand. When the push plate  14  is depressed, the liquid soap is forced out by a pump assembly  65 . The operation of the cartridge&#39;s pump mechanism  65  is illustrated in FIGS. 6A,  6 B,  6 C and  6 D. The pump mechanism  65  has a cap  21  which fits on the neck  40  of the cartridge  13 . The cap  21  is preferably bonded or otherwise securedly adhered to the cartridge  13  to prevent refilling of the cartridge  13  with an undesirable or improper product. The pump assembly  65  has a head  58  with a relatively flat upper surface. Preferably, the nozzle tip of the head  58  extends slightly downwardly and is attached to a discharge conduit or extender nozzle  59 . The discharge conduit  59  is preferably a flexible tube which is friction fit on the outside of the head&#39;s nozzle. The flexible tube  59  extends beneath the push plate  14 , and is substantially hidden from view by the lip of the push plate  14 . 
     FIG. 6A illustrates the position of the pump mechanism  65  at the outset of the dispensing operation. In this position, the atmospheric pressure in the chamber  60  forces a ball valve  61  downwardly on its valve seat, and there is a vacuum in the piston chamber  62 . A spherical valve  63  is displaced above its valve seat by means of a spring  64 . In FIG. 6B, the initial downward stroke(s) on the head  58  displace the air in the pump  65 , so that the ball valve  61  moves upwardly, and the spherical valve  63  moves downwardly. In FIG. 6C, the vacuum in chamber  62  pulls the soap product  41  into the pump  65 , so that the pump  65  is now primed. Further downward compression strokes on the head  58  dispense the product  41  upwardly through the chambers  62  and  60 , and then through the head  58  and discharge orifice  59 . A dip tube  66  extends downwardly into the cartridge  13 . The dip tube  66  is attached to the pump assembly  65  by an adapter  69 . The dip tube  66  provides for complete evacuation of the cartridge  13 . 
     In operation, the cartridge  13  is filled with liquid soap by the manufacturer or supplier of the cartridge  13 . Preferably, the cartridge  13  is inexpensive in manufacture and is intended to be disposable. The cap  21  and pump assembly  65  are secured in place on the cartridge&#39;s neck  40 . The housing  12  is pivoted away from the wall bracket  15 , and the cartridge  13  is positioned upon the floor of the housing  12 , so that the cartridge&#39;s cap  21  is in position within the housing&#39;s cutout  25 , with the discharge conduit  59  extending beneath the push plate  14 . In the preferred embodiment, there is a U-shaped guide (not shown) on the underside of the push bar  14  which maintains the extender tube  59  in the proper position. The housing  12  is then attached to the mounting bracket  15  by pivoting the housing  12  toward the plate  15  so that the two arms  30  engage with the notches within the housing  12 . 
     In order to extract the liquid soap, it is necessary only to press the push plate  14 . This operation causes the underside of the push plate  14  to contact the pump head  58  and thereby dispense a predetermined, controlled amount of liquid  41 . To remove the cartridge  13  from the mounting bracket  15 , the user grasps the upper portion of the housing  12  and pulls the housing  12  away from the bracket  15 , so as to disengage the locking arms  30 . This allows the cartridge  13  to be moved away from the bracket  14  without the use of tools. 
     It is to be understood that even though numerous characteristics and advantages of the invention have been set forth in the foregoing description, this disclosure is illustrative only. It is to be understood that the cartridge  13  could have an outwardly-projecting member which fits within a hollowed-out portion of the mounting means  15 , rather than the rib and groove embodiment illustrated. Thus, the use of the terms rib, lug groove, slot insert, and channel are not meant to restrict themselves so as to designate only a female member or a male member. Changes may be made in detail, especially in matters of shape, size and arrangement of parts, within the principles of the invention, to the full extent indicated by the broad general meaning of the appended claims.