Hands-free paper towel dispensers

Information

  • Patent Grant
  • 6293486
  • Patent Number
    6,293,486
  • Date Filed
    Monday, August 21, 2000
    24 years ago
  • Date Issued
    Tuesday, September 25, 2001
    22 years ago
Abstract
A towel dispenser comprising an electronic power system, which includes an array of one or more photovoltaic cells for energizing a control circuitry which, in turn, controls operation of the dispenser. The control circuitry is responsive to a sensing device, comprised of a motion detector, which senses rapid changes in light, which in turn, activates the dispensing of a length of paper towels when an object, such as a user's hand, is moved in front of the sensing device.
Description




FIELD OF THE INVENTION




The invention relates to towel dispensers and methods for dispensing towels. More particularly, the invention relates to electric “hands-free” towel dispensers and methods for dispensing towels without use of the hands.




BACKGROUND OF THE INVENTION




Towel dispensers are well known and are shown in U.S. Pat. Nos. 3,647,159, 4,131,044 and 4,165,138. For example, Bump, U.S. Pat. No. 3,647,159 shows a towel dispenser having an automatic towel length controlling means and roll support tensioning means. The towel dispenser disclosed generally comprises a shell, means within the shell for rotatably supporting a roll of paper toweling, a frictional power roller engaging a paper web from the roll, and means for limiting the length of individual paper towels withdrawn from the dispenser. The latter means includes a first gearlike member rotatable with the power roll, a second gearlike member rotatable in response to rotation of the first gearlike member, a finger carried by the second gearlike member, a strap mounted for linear movement on the dispenser between a first position and a second position, an abutment surface carried by the strap in a position intersecting the excursion path of the finger when the strap is in a first position, a limit abutment carried by the strap in a position intersecting the excursion path of the finger when the strap is in the second position, means temporarily holding the strap in the second position and means urging the strap toward the first position. The strap is moved toward the second position by contact of the finger with the abutment surface in response to rotation of the second gearlike member.




Electronic towel dispensers are also well known. U.S. Pat. Nos. 3,730,409, 3,971,607, 4,738,176, 4,796,825 and 4,826,262 each disclose electronic towel dispensers. For example, in Ratti, U.S. Pat. No. 3,730,409, a dispenser comprises a cabinet having a supply roll of paper towel therein and an electric motor-driven dispensing roll frictionally engaging the towel web for advancing it through a dispensing opening past a movable cutter. The cutter is biased to a normal rest position and is movable to a severing position in response to the manual cutting action by a user. The dispenser further comprises a control circuit including a normally closed start switch and a normally open ready switch connected in a series between the motor and an associated power source. The normally open stop switch is in parallel with the ready switch. Program apparatus is coupled to the cutter, the motor and the control circuit and is responsive to movement of the cutter to its severing position for opening the start switch and closing the ready switch. Movement of the cutter back to its normal rest position recloses the start switch to energize the motor. The program apparatus is responsive to operation of the motor for sequentially closing the stop switch then reopening the ready switch and then reopening the stop switch to de-energize the motor.




Finally, “hands-free” systems for controlling the operation of washroom fixtures such as water faucets, soap dispensers and towel dispensers are known. Examples of such hands-free systems are disclosed in U.S. Pat. Nos. 4,796,825, 5,031,258, 5,060,323, 5,086,526, and 5,217,035. In Hawkins, U.S. Pat. No. 4,796,825, an electronic paper towel dispenser is shown which permits paper towels to be dispensed from a supply roll by placing a hand or other object in front of a sensor located on the front of the supply cabinet. Dispensing of the paper towels is stopped when the hand is removed or when normal room lighting is not available. The dispensing of towels is controlled by a touchless switch for energizing a motor means.




The problem with prior hands-free electronic dispensers is that they require a source of electricity such as AC current from a plug-in wall outlet to power the hands-free mechanism. This can be dangerous to a user, especially when the dispenser is near a sink or other source of water. Another problem is that many prior hands-free dispensers are complicated devices which are expensive to manufacture and difficult to maintain in working order. Still another problem is that prior hands-free dispensers continue to dispense paper so long as the user's hand remains in front of the sensor. Also, if a change in ambient light occurs, prior hands-free dispensers have to be manually reset to adjust to a new light reference.




Therefore, it is an object of the present invention to provide improved towel dispensers for automatically dispensing a length of towel in response to the movement of an object such as a user's hands. In this manner, a user can avoid contact with viruses or bacteria on the dispenser left by prior users' hands. It is a further object to provide energy-efficient hands-free dispensers which utilize light energy. It is another object to provide hands-free dispensers which are simple in design, safe and easy to use. It is yet another object to provide hands-free dispensers which are inexpensive to manufacture and free from problems such as inoperability due to jamming or changes in ambient light conditions.




SUMMARY OF THE INVENTION




The invention comprises a hands-free towel dispenser comprising a unique electronic power system. The electronic power system comprises an array of one or more photovoltaic cells which energizes a unique control circuitry which in turn controls operation of the dispenser. The control circuitry is responsive to a sensing device which activates the dispensing of a length of paper towels when an object such as a user's hand is moved in front of the sensing device.




The hands-free-dispenser of the invention comprises:




(a) a housing means for containing towels;




(b) a sensing means for detecting an object such as a person's hand;




(c) a dispensing means for dispensing a towel when said sensing means detects the object;




(d) an electric power source for powering said dispensing means;




(e) control circuitry for controlling the dispensing means; and




(f) an array of one or more photovoltaic cells for energizing said control circuitry.




Preferably, the sensing means comprises a motion detector which senses rapid changes in light. Also, preferably, the electric power source is a rechargeable battery which is in turn recharged by the array of one or more photovoltaic cells.











DESCRIPTION OF THE DRAWINGS




These and other features of the invention will now be described with reference to the drawings of preferred embodiments, which are intended to illustrate and not to limit the invention and in which:





FIG. 1

is a perspective view of an embodiment of the towel dispenser of the invention;





FIG. 2

is a perspective view of the towel dispenser of

FIG. 1

with the towel roll removed;





FIG. 3

is a sectional view of a side elevation of the towel dispenser of

FIG. 2

;





FIG. 4

is a board layout for a mechanical plate used in the dispenser of the invention;





FIG. 5

is a schematic diagram for the electric circuit of he invention;





FIG. 6

is a block diagram describing operation of the hands free dispenser;





FIG. 7

is a block diagram describing operation of the safety shut off feature of the dispenser; and





FIG. 8

is a block diagram describing how the battery is charged by the array of one or more photovoltaic cells.











DETAILED DESCRIPTION OF THE INVENTION




The term “hands-free” means control of a dispensing means without the need for use of hands.




The term “towel” refers generally to an absorbent paper or other suitable material used for wiping or drying.




As shown in

FIG. 1

, in a preferred embodiment of the invention, a hands-free towel dispenser


10


comprises a cabinet


12


comprising a back wall


14


, two side walls


16


,


18


, a top wall


20


, a bottom or base wall


22


, and an openable and closeable front cover


24


. The front cover


24


may be pivotally attached to the cabinet, for example, by hinge


26


, for easy opening and closing of the cover


24


when a supply of towels such as main roll


28


is placed in the cabinet


12


. The towel dispenser


10


may be mounted to a wall or other supporting member by any convenient means such as brackets, adhesives, nails, screws or anchors (not shown).




As shown in more detail in

FIGS. 2

,


3


and


4


, the hands-free dispenser


10


further comprises a dispensing means for dispensing a length of towel to the outside of the dispenser


10


. Such dispensing means may comprise drive roller


32


, pinch roller


34


, transfer bar


36


and roll support cup


38


A and roll, support arm


38


B. The dispensing means enables dispensing of a predetermined length of towel to the outside of the towel dispenser


10


through slot


40


, where the towel can be grasped by the user and torn off along a serrated edge


43


of a blade


42


.




The dispensing means operates to dispense towels either from a main roll


28


or a stub roll


30


. The means for controlling dispensing of paper from the main roll


28


once the stub roll


30


has been depleted comprises a transfer bar


36


, which is described in detail in U.S. Pat. No. 4,165,138, the disclosure of which is incorporated by reference herein.




As shown in

FIGS. 1

,


2


and


3


, main roll


28


is first loaded into the cabinet


12


onto roll support cup


38


A and roll support arm


38


B located opposite each other on side walls


16


,


18


, respectively, and forming main roll station


48


(FIG.


1


). A length of towel from main roll


28


is then threaded behind transfer bar


36


including a fork


37


A and a cam


37


B, and over drive roller


32


so that towel sheeting


50


will be pulled between the drive roller


32


and the pinch roller


34


in a generally downward motion when the drive roller


32


is rotated by operation of a motor


88


shown in FIG.


4


. As the towel sheeting


50


is pulled downwardly, it is guided along a wall


52


of the serrated blade


42


and out slot


40


.




The length of towel sheeting


50


dispensed from towel dispenser


10


can be set to any desired length. Preferably, the dispenser


10


releases about ten to twelve inches of towel sheeting


50


per dispensing cycle. The towel sheeting


50


is then removed by tearing the length of dispensed towel sheeting


50


at the serrated edge


43


of blade


42


.




When the main roll


28


has been partially depleted, preferably to about a four-inch diameter as indicated by low paper indicator


56


, the dispenser cover


24


is opened by an attendant, and the main roll


28


is moved down to a stub roll station


54


. The main roll


28


then becomes stub roll


30


and enables a new main roll


28


to be loaded onto roll support cup


38


A and roll support arm


38


B in main roll station


48


. When stub roll


30


is completely depleted the new main roll


28


begins feeding paper


50


between the drive roller


32


and pinch roller


34


out of the dispenser


10


when the motor


88


is activated.




When the low paper indicator


56


indicates that the new main roll


28


is low, the attendant opens cover


24


, an empty core (not shown) of stub roll


30


is removed from the stub roll station


54


and discarded, and new main roll


28


is dropped into position into the stub roll station


54


where it then becomes stub roll


30


and continues feeding. A main roll


28


is then positioned on the roll support cup


38




a


and roll support arm


38




b


. The basic transfer mechanism for continuously feeding towels from a stub roll until completely used and then automatic transfer to a main roll is described in detail in U.S. Pat. No. 4,165,138.




Hands-free operation of the dispenser


10


is effected when a person places an object such as their hands in front of a photo sensor


82


shown in FIG.


4


. The photo sensor


82


activates the motor


88


to dispense a predetermined length of towel sheeting


50


. The dispenser


10


has electric circuitry which, as will be described below with reference to

FIGS. 4-8

, ensures safe, efficient and reliable operation of the dispenser


10


.




Referring now to

FIG. 4

, a cutaway view of a portion of the dispenser


10


is shown. In

FIG. 4

, a circuit board


81


is mounted to a mechanical plate


80


of the dispenser


10


. Note that the circuit board is mounted between the mechanical plate


80


and the wall


16


of the Cabinet


12


. The photo sensor


82


is seated within a mounting tube


83


and is coupled to the circuit board


81


by leads or wires


84


,


85


. As will be described below with reference to

FIG. 5

, the photo sensor


82


reacts to changes in light intensity. Light passes from a room, through an opening


86


in the movable front cover


24


of the dispenser


10


, to the photo sensor


82


. A clear plastic lens


87


is fitted into the opening


86


. The lens


87


prevents debris from clogging or blocking the opening


86


which might prevent light from reaching the sensor


82


. The lens


87


also prevents debris from falling into the dispenser


10


which might cause the dispenser


10


to malfunction.




Also shown in

FIG. 4

is the motor


88


which is attached to the drive roller


32


. The motor


88


, including a gearbox (not shown), are available from Skil Corporation in Chicago, Ill. The motor


88


is placed partially within the drive roller


32


and is powered by a rechargeable battery


90


, also available from Skil Corporation. The battery


90


is coupled to the motor


88


via the circuit board


81


by wires or leads


92


,


94


which are connected or soldered to the circuit board


81


.




An array of one or more photovoltaic cells


96


, is located on the top


20


of the dispenser as shown in FIG.


1


. The array of one or more photovoltaic cells


96


shown is made by Solarex Corporation in Fredericks Md. The array of one or more photovoltaic cells


96


is coupled to the battery


90


and control circuitry


98


via the circuit board


81


by wires or leads


100


,


102


which are connected or soldered to the circuit board


81


also.




The array of one or more photovoltaic cells


96


provides power to control circuitry


98


for controlling the dispensing means of the dispenser


10


. In a preferred embodiment, the array of one or more photovoltaic cells


96


provides power to control circuitry


98


(

FIG. 5

) which will manage motion sensing, rotation control, safety features, and recharging of the battery


90


. In a second embodiment, the array of one or more photovoltaic cells


96


provides power to the control circuitry


98


which will manage motion sensing, rotation control and safety features, but the battery


90


will be replace at desired intervals and will not be recharged by the control circuitry


98


. When the array of one or more photovoltaic cells


96


is not exposed to light, the array of one or more photovoltaic celis


96


does not supply power to the control circuitry


98


and the motor


88


cannot be turned on. The array of one or more photovoltaic cells


96


functions as an on-off switch for the dispenser


10


and thereby prevents the battery


90


from becoming unnecessarily discharged when the lights are off. If the control circuitry


98


is not powered by the array of one or more photovoltaic cells


96


, the motor


88


cannot be turned on.




Referring now to

FIG. 5

, a schematic diagram of the control circuitry


98


is: shown. The control circuitry


98


controls the “hands-free” operation of the dispenser


10


. More specifically, the control circuitry


98


controls and/or performs the following functions: (1) sensing when an object such as a person's hand is in front of the photo sensor


82


and turning the motor


88


on; (2) sensing when the proper length of towel sheeting


50


has been dispensed and then turning the motor


88


off; (3) sensing when towel sheeting


50


has jammed inside of the dispenser


10


and turning the motor


88


off; (4) sensing when the front cover


24


of the dispenser


10


is open and preventing operation of the motor


88


; (5) creating a short delay, preferably about two seconds, between dispensing cycles; and (6) charging of the battery


90


by the solar panel


96


.




The values of the components shown in the schematic diagram of

FIG. 5

are as listed below:

















RESISTORS


















R1 =




1 × 10


6






ohm




R7 =




1 × 10


6






ohm







R2 =




520 × 10


3






ohm




R8 =




20 × 10


3






ohm







R3 =




1 × 10


6






ohm




R9 =




680




ohm







R4 =




3 × 10


6






ohm




R10 =




8




ohm







R5 =




3.3 × 10


6






ohm




R11 =




1 × 10




ohm







R6 =




10 × 10


6






ohm




R12 =




1 × 10


6






ohm











CAPACITORS


















C1 =




1 × 10


−6






Farad




C4 =




104 × 10


−6






Farad







C2 =




1 × 10


−6






Farad




C5 =




1 × 10


−6






Farad







C3 =




104 × 10


−6






Farad




C6 =




1 × 10


−6






Farad















OTHER COMPONENTS




All diodes are part nos. IN4148 or IN914 from Diodes, Inc.




Operational Amplifiers IC1A and IC1B are on circuit board ICL7621DCPA from Maxim.




Transistors Q


1


and Q


2


are part no. 2N3904 from National.




Transistor Q


3


is part no. 2N3906 from National.




The array of one or more photovoltaic cells are part nos. NSL-4532 or NSL-7142 from Solarex.




Reed switches RD1 and RD2 are part no. MINS1525-052500 from P-CLAIRE.




Relay RLY1 is part no. TF2E-3V from AROMAT.




The photo sensor


82


shown is a Cadmium Sulfide (“CDS”) motion detector manufactured by Silonex Corporation located in Plattsburg, N.Y. The photo sensor


82


is a variable resistance resistor. The resistance of the photo sensor


82


changes depending on the amount of light to which the photo sensor


82


is exposed. If the amount of light on the photo sensor


82


is high, the photo sensor's resistance becomes relatively low. If the amount of light on the photo sensor


82


is low, the photo sensor's resistance becomes relatively high.




In ambient light, the photo sensor


82


has a certain resistance which causes voltage V


A


to be less than a reference voltage V


B


. Voltage V


A


and reference voltage V


B


are the positive and negative inputs, respectively, of operational amplifier IC


1


A. When voltage V


A


is less than reference voltage V


B


, the operational amplifier IC


1


A output voltage V


M1


, goes to negative, i.e., V


M1


is at zero voltage. When voltage V


M1


is at zero voltage, the motor


88


will not operate.




Note that the reference voltage V


B


is determined by and adjusts according to the ambient light level in a room. Therefore, the reference voltage V


B


is not preset to any particular light level. A reference voltage circuit


104


sets the reference voltage V


B


according to the ambient light level of a room. Because the reference voltage circuit


104


sets the reference voltage V


B


according to the ambient light level in a room, no adjustments need to made to the dispenser


10


based on how high or low the ambient light level is for a particular room.




Furthermore, the combination of the photo sensor


82


and the reference voltage circuitry


104


permit the photo sensor


82


to trigger the dispenser


10


when a person's hand comes within approximately 10-12 inches from the sensor


82


.




The reference voltage circuit


104


includes resistors R


2


and R


3


and capacitor C


1


. Resistors R


2


and R


3


are connected to the positive terminal, PHOTOVOLTAIC CELL+, of the array of one or more photovoltaic cells


96


which provides a voltage B


+


when the array of one or more photovoltaic cells


96


is exposed to light. In ambient light, voltage V


A


is approximately 0.5(B


+


).




When a person places an obtrusion such as their hand within a predetermined distance of the photo sensor


82


, preferably within 10-12 inches, the amount of light reaching the photo sensor


82


is decreased sufficiently to cause the photo sensor's resistance to increase to a level where voltage V


A


becomes greater than voltage V


B


and thereby causes the output V


M1


of operational amplifier IC


1


A to be a positive voltage.




The operational amplifier IC


1


A output voltage V


M1


is passed through diode D


1


and is coupled to the positive input of operational amplifier IC


1


B. Reference voltage V


C


is provided between resistors R


5


and R


6


and is the negative input of operational amplifier IC


1


B. If voltage V


M1


is greater than reference voltage V


C


, then the output of the operational amplifier IC


1


B, V


M2


, is at a positive voltage. When the output voltage V


M2


is at positive voltage, n-p-n transistor Q


1


is closed, thereby causing a current to flow through coil CL


1


which in turn closes coil relay RLY


1


. When RLY


1


is closed, the motor


88


runs because the motor's positive terminal, MOTOR+, is connected to the battery's positive terminal, BATTERY+.




In order to stop the motor


88


from turning after a predetermined amount of towel sheeting


50


has been dispensed, a roller sensing circuit


106


is provided. The roller sensing circuit


106


includes a magnet,


108


, an n-p-n transistor Q


3


, a capacitor C


6


, resistors R


7


and R


8


and a reed switch RD


1


. The magnet


108


is mounted on drive roller


32


. The magnet


108


activates or closes the reed switch RD


1


when the magnet


108


is aligned with the reed switch RD


1


. When the reed switch RD


1


is closed, a one time voltage drop is made across capacitor C


6


. The voltage drop across capacitor C


6


turns on transistor Q


3


which causes voltage V


M1


to drop to less than reference voltage V


C


and therefore produces a negative output or zero voltage output V


M1


from operational amplifier IC


1


B and stops the motor


88


from operating. By changing the radius of the drive roller


32


, the length of paper


50


that is dispensed can be varied.




The time it takes for the motor


88


to turn the drive roller


32


one full turn, i.e., the time it takes for the magnet


108


to become aligned with reed switch RD


1


, is approximately 0.47 seconds. When the drive roller


32


has made one full turn, the predetermined amount of towel sheeting


50


has been dispensed and the magnet


108


is aligned again with the reed sensor RD


1


to stop operation of the motor


88


, as described above. Preferably, the motor


88


will power an approximately 3-4 inch diameter roller for one revolution, sufficient to dispense approximately 10-12 inches of paper towel


50


. If the reed sensor RD


1


is not activated within 1.0 second, e.g., if a paper jam occurs, a safety timer circuit


110


turns the motor


88


off.




The safety timer circuit


110


includes capacitor C


2


and resistor R


4


. If the reed switch RD


1


does not sense the magnet


108


within 1.0 second, the safety timer circuit


110


causes voltage V


M1


to drop below reference voltage V


C


and thereby causes output voltage V


M2


to be at zero volts and turns the motor


88


off.




When the front cover


24


is open, e.g., to add towel sheeting


50


in the dispenser


10


, the motor


88


is prevented from operating by a door safety circuit


120


. The door safety circuit


120


includes resistors R


5


and R


6


, a reed switch RD


2


and a magnet


121


. One lead


122


of the reed switch RD


2


is attached to resistor R


5


and the other lead


124


is attached to ground G


2


. Reference voltage V


C


is created between resistors R


5


and R


6


. When the front cover


24


is open, the reed switch RD


2


is open and causes voltage V


C


to be higher than voltage V


M1


and therefore causes the output voltage, V


M2


, of operational amplifier IC


1


B to be at zero voltage. Note that voltage V


M2


is never higher than voltage B+.




When the front cover


24


is closed, the magnet


121


causes the reed switch RD


2


to close and allows reference voltage V


C


to be less than voltage V


M1


, which in turn causes the output voltage V


M2


of operational amplifier IC


1


B to be at positive voltage and turns the motor


88


on.




In ambient room light, the array of one or more photovoltaic cells


96


generates enough current to power the control circuitry


98


. In the preferred embodiment (shown in FIG.


5


), the array of one or more photovoltaic cells


96


generates enough current to also charge the battery


90


. In this preferred embodiment, a positive lead, PHOTOVOLTAIC CELL+, of the array of one or more photovoltaic cells


96


, is connected to battery charging circuitry


126


.




The battery charging circuitry


126


includes a diode D


5


, resistors R


11


and R


16


, a capacitor C


4


and a p-n-p transistor Q


2


. The positive lead, PHOTOVOLTAIC CELL+, of the array of one or more photovoltaic cells


96


charges capacitor C


4


through resistor R


16


. When capacitor C


4


is charged to a certain voltage level, preferably approximately 1.2 volts higher than the battery voltage B


+


, resistor R


11


biases the capacitor C


4


to discharge through the p-n-p transistor Q


2


and into the positive terminal, BATTERY+, of the battery


90


. As long as light reaches the array of one or more photovoltaic cells


96


, the battery charging process will be repeated and the array of one or more photovoltaic cells


96


continually charges the capacitor C


4


and battery


90


.




In the second embodiment (not shown), the array of one or more photovoltaic cells


96


only provides power to the control circuitry


98


. Disposable, D-cell batteries (not shown) or other disposable batteries can be used to power the motor


88


, instead of the rechargeable battery


90


. Because the control circuitry


98


is powered by the array of one or more photovoltaic cells


96


, the motor


88


will not operate unless there is light in the room, thus preventing the disposable batteries from becoming unnecessarily discharged. After the disposable battery has been fully discharged, the disposable battery can be replaced.




The control circuitry


98


also includes delay circuitry


112


to prevent the dispenser


10


from starting a new cycle of dispensing towel sheeting


50


until a predetermined time after the motor


88


has turned off from a prior dispensing cycle. The predetermined time is preferably approximately 2 seconds. The delay circuitry


122


includes a diode D


2


, resistor R


3


, and capacitor C


1


.




When voltage V


M2


is high, the motor


88


is running and causing towel sheeting


50


to be despensed from the despenser


10


. When V


M2


is high, capacitor C


1


is charge to a very high level, forcing reference voltage V


B


very high. It takes approximately 2 seconds for V


B


to return to its ambient light level setting. During that time, if a person places their hand in front of the photo sensor


82


, voltage V


A


will not be forced higher than V


B


. As a result, the motor


88


cannot be turned on again until approximately 2 seconds after it has been turned off. This prevents a continual discharge of towel sheeting


50


from the dispenser which could cause the battery


90


to discharge and the motor


88


to burn out.




The manner in which the motor


88


is turned on is described in the flowchart of FIG.


6


. The motor


88


cannot be turned on if there is not ambient light in the room to power the control circuitry


98


. The array of one or more photovoltaic cells


96


acts as an “on-off” switch for the dispenser


10


and will not permit the dispenser


10


to dispense towel sheeting


50


unless there is sufficient light in the room. If there is sufficient light in the room to power the control circuitry


98


, the various checks, which have been described above with reference to the circuitry in

FIG. 5

, are shown in the flowchart of FIG.


6


. These checks are performed before the motor


88


is turned on.




The manner in which the motor


88


is turned off, which has been explained above with reference to

FIG. 5

, is described in the flowchart in FIG.


8


. Similarly, the charging of the battery


90


by the array of one or more photovoltaic cells


96


, which has been explained above with reference to

FIG. 5

, is described in the flowchart of FIG.


8


.




The embodiments of the inventions disclosed herein have been discussed for the purpose of familiarizing the reader with novel aspects of the invention. Although preferred embodiments have been shown and described, many changes, modifications, and substitutions may be made by one having skill in the art without necessarily departing from the spirit and scope of the invention.



Claims
  • 1. A hands-free towel dispenser comprising:(a) a housing means for containing towels; (b) a sensing means for detecting an object; (c) a dispensing means for dispensing a towel when said sensing means detects the object; (d) an electric power source for powering said dispensing means; (e) control circuitry for controlling the dispensing means; and (f) a solar panel for energizing said control circuitry.
  • 2. The hands-free towel dispenser of claim 1 wherein said sensing means comprises a variable resistor which changes in response to changes in light levels.
  • 3. The hands-free towel dispenser of claim 1 wherein said electric power source is a battery.
  • 4. The hands-free towel dispenser of claim 3 wherein said electric power source is a rechargeable battery.
  • 5. The hands-free paper towel dispenser of claim 4 wherein said solar panel also charges said rechargeable battery.
  • 6. The hands-free towel dispenser of claim 1 wherein said housing means comprises a movable front cover.
  • 7. The hands-free towel dispenser of claim 6 wherein said dispensing means includes means for detecting when said cover is open and preventing dispensing of a towel until said cover is closed.
  • 8. The hands-free towel dispenser of claim 1 wherein said dispensing means includes a drive roller mounted in said housing means and a motor coupled to said drive roller.
  • 9. The hands-free towel dispenser of claim 8 wherein said dispensing means further includes means for sensing when said drive roller has dispensed a predetermined amount of paper.
  • 10. A method of dispensing paper towel from a hands-free paper towel dispenser including a housing, a dispensing mechanism for dispensing paper from the dispenser, a sensing mechanism for sensing the presence of an object, control circuitry for controlling the dispensing mechanism, a power source for powering the dispensing mechanism, and a solar panel, comprising the steps of:providing power to the control circuitry from the solar panel; and, if the control circuitry is powered, sensing when an object is within a predetermined distance from the sensing mechanism; dispensing a predetermined amount of paper from the dispenser.
  • 11. A hands-free towel dispenser comprising:(a) a housing defining an interior space sufficient to contain at least one roll of towel, said housing including a front cover; (b) a sensor disposed entirely within the interior space of said housing and mounted at a location spaced from the front cover, said sensor being oriented toward the front cover of the housing in order to permit detecting of an object adjacent the front cover, and said sensor being constructed to detect an object without the object contacting the front cover; (c) a dispensing mechanism disposed within the interior space of the housing for dispensing a length of towel, the dispensing mechanism including a drive roller and a motor in driving engagement with the drive roller, said dispensing mechanism is structured to dispense a predetermined length of towel when said sensor detects an object; (d) an electric power source for powering operation of the dispenser; (e) control circuitry controlling operation of the dispenser, said control circuitry being structured to: (i) control operation of said motor and provide a delay between cycles of towel dispensing (ii) control the predetermined length of towel that is dispensed; and (iii) detect a jam in the towel being dispensed.
Parent Case Info

This application is a continuation of Application Ser. No. 09/085,289, filed May 27, 1998, now U.S. Pat. No. 6,105,898, which is a continuation of Application Ser. No. 08/603,051, filed Feb. 16, 1998, now U.S. Pat. No. 5,772,291.

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Continuations (2)
Number Date Country
Parent 09/085289 May 1998 US
Child 09/642866 US
Parent 08/603051 Feb 1998 US
Child 09/085289 US