BACKGROUND- The present invention relates to the field of pump operated dispensers. 
- Pump operated dispensers, such as soap dispensers used to dispense liquid hand soap in public restrooms, deliver contents from a container of the dispenser to a dispensing portion that may be located at or near a top of the container. 
- “Touchless” soap dispensers typically utilize an electric motor that drives a pump to which it is coupled, and that is activated in response to a signal delivered upon the activation of a switch or sensor of the dispenser system, such as a motion detector or other optic sensor. Upon receiving the signal, the rotor rotates to drive a drive shaft of the pump located within the container to dispense an amount of soap. Such a configuration may require the motor to be mounted within the container of the soap dispenser, or may require a physical connection through a portion of the container for physically coupling the motor to the mechanics of the pump located within the container to drive the drive shaft. However, submersible motors require special sealing to protect components of the motor, while physical connections through the container may require special sealing of the system to prevent liquid from leaking from the container. Furthermore, such configurations may lead to deterioration of the motor and the moving parts associated with the mechanics of the pump due to stress and friction. Thus, a fluid dispenser having fewer parts and/or fewer mechanical couplings is desired. 
SUMMARY- According to embodiments of the present invention, a pump located within a container is operated by rotation of a rotor coupled to a drive shaft of the pump to dispense fluid contents of the container by driving the pump. The rotor includes one or more magnets, and is driven by a rotating magnetic field created by a plurality of coils that are located on an exterior of the container in sufficient proximity to the magnets of the rotor. 
- According to one embodiment of the present invention, there is provided a fluid dispenser including a container configured to store a fluid, a pump for placement in an interior of the container and for pumping contents of the container to an exterior of the container, a motor system for driving the pump and including a rotor for placement in the interior of the container, and a stator for placement on the exterior of the container, wherein an electric current is passed through the stator for causing rotation of the rotor. 
- The fluid dispenser may further include a cap configured to be coupled to the container, and the pump may be configured to be coupled to the cap. 
- The cap may be configured to be threadably coupled to the container. 
- The stator may include three coils electrically coupled in a delta pattern or a star pattern. 
- The three coils may be shaped to form a ring and may be configured to be driven by three half bridges in an open loop. 
- The fluid dispenser may further include a processor for regulating the electric current through the stator, and a sensor for sensing an object proximate the sensor and for sending a sensor signal to the processor. 
- The pump may be for pumping the contents in response to the sensor signal generated by the sensor. 
- The electric current through the stator is regulated using at least one of a pulse-width modulated (PWM) signal or variable frequency. 
- The sensor signal may be generated upon detection of motion of a user. 
- The processor may be configured to have the electric current passed through the stator upon receiving the sensor signal. 
- The fluid dispenser may further include a flexible circuit for carrying at least one of the sensor signal and the electric current through the stator. 
- The rotor may include a ring magnet. 
- The fluid dispenser may further include a battery for delivering the electric current through the stator. 
- The fluid dispenser may further include a processor configured to regulate electric current through the stator corresponding to a voltage level of the battery. 
- The fluid dispenser may further include a dispensing end fluidly coupled to the pump for dispensing the fluid pumped by the pump. 
- The fluid dispenser may further include a drive shaft for coupling the pump to the rotor. 
- The electric current may cause the stator to produce a magnetic field substantially surrounding the rotor for causing rotation of the rotor. 
- The rotor may include a plurality of magnets. 
- According to another embodiment of the present invention, there is provided a motor system for driving a pump for pumping contents of a container includes a rotor for placement in an interior of the container, and a stator for placement on an exterior of the container. 
- According to yet another embodiment of the present invention, there is provided a pump assembly including a container, a pump for pumping contents of the container, and a motor system for driving the pump and including a rotor for placement in an interior of the container, and a stator for placement on an exterior of the container. 
- According to another embodiment of the present invention, there is provided a method of dispensing a fluid from a container, the method including providing a magnetic field using a stator, moving a magnet in response to the magnetic field, driving a pump in response to the motion of the moving magnet, and pumping the fluid from the container with the pump. 
- Accordingly, embodiments of the present invention provide a submersible pump located inside a container and magnetically driven by a magnetic field generated on an exterior of the container. 
BRIEF DESCRIPTION OF THE DRAWINGS- FIG. 1 is a cross-sectional view of a bottom cap for a container with a pump and rotor coupled thereto, and a set of coils for causing rotation of the pump rotor according to an embodiment of the present invention; 
- FIG. 2 is a sectional view of the container of an embodiment of the present invention that is configured to be coupled to the bottom cap of the embodiment of the present invention shown inFIG. 1; 
- FIG. 3 is a perspective view of the container of the embodiment shown inFIG. 2 assembled with a dispensing end and the bottom cap of the embodiment shown inFIG. 1 according to an embodiment of the present invention; 
- FIG. 4 is a partial cross sectional view of a container with a bottom cap coupled thereto and a housing containing a set of coils for causing rotation of a pump rotor according to another embodiment of the present invention; 
- FIG. 5A is a schematic view showing magnetic coils of a stator in a delta pattern that are powered by a battery pack and coupled to a sensor and to a processor, according to an embodiment of the present invention; 
- FIG. 5B is a schematic view showing magnetic coils of a stator in a star pattern, according to an embodiment of the present invention; and 
- FIG. 6 is a perspective view of coils of a stator circumscribing/surrounding a rotor coupled to a pump, according to an embodiment of the present invention. 
DETAILED DESCRIPTION- Embodiments of the present invention may include an assembly including a container, a container end cap, and a pumping mechanism including a pump rotor. These features may be similar to those that are disclosed in U.S. Patent Application Publication 2010/0213208 A1, which is fully incorporated herein by reference. Furthermore, other features disclosed in U.S. Patent Application Publication 2010/0213208 A1 may be incorporated with embodiments of the present invention. Accordingly, some components of embodiments of the present invention that are included in the incorporated reference are not discussed at length herein. 
- Referring toFIG. 1, a bottom cap, a pump, a rotor, and a set of magnetic coils for causing rotation of the rotor of a fluid dispensing system according to a first embodiment of the present invention is shown. 
- According to the present embodiment, abottom cap22 hasthreads19 to enable thebottom cap22 to be coupled to a threadedbase section14 of acontainer12, which is configured to contain a material (e.g., a fluid such as a liquid) to be dispensed, to seal a bottom opening18 of the container12 (seeFIG. 2). Coupled to thebottom cap22 is apump58. Apump58 is mounted in apump mount54 at thebottom cap22, which is removably coupled to thebottle12. 
- Although thepump58 of the present embodiment is coupled near a bottom of thecontainer12, different applications of embodiments of the present invention may be configured to have thepump58 differently located. Furthermore, although embodiments of the present invention are described with reference to a pump for pumping a fluid or liquid, other embodiments of the present invention may be used to pump other materials, such as gasses, foams, or slurries or other types of fluids. 
- One ormore magnets68, such as an electromagnet, a permanent magnet, a ring magnet, or one or more magnet segments, are part of, or may be mounted on or coupled to, an impeller of therotor69 that is coupled to adrive shaft62 of thepump58 for driving the pump. The magnet or magnet segment(s)68 act(s) as arotor69 of thepump58 to be driven by astator91 and to be used as an integrated part of an open frameDC servo motor20, such as an open frame brushless DC servo motor. Driving thedrive shaft62 of thepump58 causes the fluid contained in thecontainer12 to pass through aninlet70 of thepump58 and be pumped by the pump to anoutlet72 of thepump58, wherein theoutlet72 may be coupled to a tube76 (seeFIG. 2) used to dispense the fluid from near the bottom of thecontainer12. 
- According to the present embodiment, the magnet or magnet segment(s)68 may be driven by manipulating a magnetic field produced by thestator91, which substantially circumscribes the magnet or magnet segment(s)68, although different embodiments of the present invention may use various configurations of theservo motor20, wherein thestator91 is able to drive therotor69 via the magnetic field. This magnetic field may be produced by an electromagnet, such aselectromagnetic coils24 which form thestator91, or may be produced by some other device that is placed in proximity to thebottle12 so as to cause motion of the magnet or magnet segment(s)68 attached to thedrive shaft62 of thepump58, causing thedrive shaft62 to rotate. Accordingly, theelectromagnetic coils24 are operated as thestator91 of the openframe servo motor20 of the present embodiment. Furthermore, as shown inFIGS. 5A,5B, and6, theelectromagnetic coils24 may consist of threecoils24a,24b,and24c. 
- By using the above described openframe servo motor20, thefluid dispensing system10 of the present embodiment eliminates the need for moving parts that are external to thecontainer12. Furthermore, the need to align thestator91 with therotor69 becomes less critical, making effective driving of thepump58 with thestator91 more easily accomplished. 
- According to the present embodiment, thestator91 includes three ormore coils24 formed in the shape of a ring to be located outside of thebottom cap22, allowing thestator91 to be anopen frame stator91 without commutator, as shown inFIG. 1. Upon assembly, theopen frame stator91 is placed in proximity to an exterior of thebottom cap22 housing therotor69, thereby removing the need for moving parts outside of thebottle12 that are physically coupled to parts within the bottle12 (i.e., coupling of the motor external to the bottle to the pump within the bottle). Accordingly, embodiments of the present invention obviate the need for having an opening in thebottle12 at the motor-pump connection, and also enable the operation of thepump58 without a constant force directly applied to therotor69 and driveshaft62, thereby decreasing wear of the components of the dispensingsystem10. 
- Although the present embodiment shows abottom cap22 that is engageable with thebottle12, and that may be removed from thebottle12, other embodiments of the present invention may include one-piece, or integrally formed, bottle/cap structure. 
- Referring toFIG. 2, a container section, which is configured to be coupled to thebottom cap22 of the embodiment shown inFIG. 1, of a fluid dispensing system of an embodiment of the present invention is shown. 
- Thefluid dispensing system10 according to the present embodiment includes a substantially cylindrically-shapedbottle12 for holding the fluid to be dispensed, although differently shaped containers may be used to contain the fluid without departing from the spirit or scope of the present invention. At thetop4 of thebottle12 is aneck section16, which may be threaded108 to threadably couple thebottle12 to a spout dispensing end28 (seeFIG. 3). Furthermore, thetube76 coupled to theoutlet72 of thepump58 may be coupled to theoutlet112 to deliver the fluid to thespout dispensing end28. 
- FIG. 3 is a perspective view of an assembled fluid dispenser according to an embodiment of the present invention. 
- Referring toFIG. 3, according to the present embodiment, theservo motor20 may be activated in response to a signal from amotion detecting sensor38, an optic sensor, an infrared sensor, or some other type of switch or no-touch sensor. Thesensor38 may send an activation signal to the processor99 (shown schematically inFIGS. 5A and 5B), which in turn uses, for example, software to direct the operation of thestator91 to drive theservo motor20. It should be noted, however, that theservo motor20 of other embodiments of the present invention may be driven using hardware. Furthermore, pulse-width modulated (PWM) signals may be sent to the stator, and thefluid dispensing system10 may transmit various signals via wiring or a circuit, such as aflexible circuit41. 
- Theprocessor99 and software may also be used to monitor a voltage drop of a battery pack97 (shown schematically inFIGS. 5A and 5B) including one or more battery cells used to power theservo motor20. Commonly, a voltage drop of a power source used to power a DC motor would result in change in performance, or speed, of the DC motor. Therefore, if such a DC motor were coupled to thepump58 of the present embodiment, variations in voltage applied to the DC motor could potentially lead to variations in amounts of fluid or liquid dispensed. Accordingly, if a voltage drop is sensed, the software of embodiments of the present invention is capable of adjusting the PWM signals, or otherwise controlling power to thecoils24 of thestator91, to ensure that a more closely uniform amount of fluid is dispensed. 
- Although abattery pack97 is described, other embodiments of the present invention may use a power supply other than thebattery pack97. Furthermore, according to the present embodiment, the speed of theservo motor20 may be controlled by controlling a frequency of a signal delivered thereto. By controlling the frequency of the signal, the rate of rotation of the magnetic field provided by thestator91 may be more uniform, which in turn causes the speed of therotor69 to be more uniform. Variations in the rate of rotation of therotor69 may otherwise cause variations in the performance of the pump58 (e.g., amounts of fluid pumped by thepump58 may vary). By controlling theservo motor20 using, for example, frequency-based signals, and PWM signals, variations in voltage delivered to theservo motor20 will have less of an effect on performance of theservo motor20, and amounts of fluid or liquid output in response to activation of thesensor38 will be more consistent. 
- Furthermore, the software may also be used to control the speed, direction, and torque of the magnet or magnet segment(s)68 coupled to thedrive shaft62 by adjusting and controlling the PWM signals. In the present embodiment, the openframe servo motor20 is a brushless direct current (DC)motor20. Accordingly, the magnet or magnet segment(s)68 may be driven by the set ofelectromagnetic coils24 of thestator91, which may be driven according to the PWM signals from theprocessor99 to create a rotating magnetic field in proximity to thebottle12. 
- FIG. 4 shows components of a fluid dispenser according to another embodiment of the present invention. 
- Referring toFIG. 4, the openframe servo motor20 of thefluid dispenser10 of the present embodiment includes threecoils24 electrically coupled in a delta pattern (seeFIG. 5A) or coupled in a star pattern (also referred to as a “Y” pattern, seeFIG. 5B) as thestator91. The openframe servo motor20 may be driven by threehalf bridges98a,98b,98c(seeFIGS. 5A and 5B) on a PC Board in an open loop, without feedback. The threehalf bridges98a,98b,98cmay be controlled by theprocessor99, such as a microprocessor or microcontroller. An output signal of theprocessor99 of the present embodiment is a pulse-width modulated (PWM) signal used to control current through the delta-connectedcoils24 and to control an output sequence and frequency for controlling speed and direction of theservo motor20, and in turn controlling the dispensing of fluid via thespout dispensing end28. 
- While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that features of different embodiments may be combined to form further embodiments, and that various changes in form and details may be made therein, without departing from the spirit and scope of the present invention as defined by the following claims and their equivalents.