Abstract:
A sterilizer for small items which sterilizes items using ultraviolet light in the UV-C range. The sterilizer features a housing which encloses a removable basket or other receptacle made of a material or structure which is ‘transparent’ to UV-C radiation for enclosing items to be sterilized, a motor or other means for turning the receptacle inside the housing, a source of UV light, a door to seal the housing and prevent the leakage of UV light and means for moving the receptacle inside the housing and to activate the UV source. The UV light is directed through the basket and onto the items to be sterilized. As the basket is moved along a rotational axis, the items to be cleaned are continuously moved, insuring that UV light hits all surfaces of each item to be sterilized. The UV light destroys microorganisms on the surfaces of the items to be sterilized. The items are removed from the device in a sterilized state.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention is generally directed to a novel device for sterilizing toys, pacifiers, bottles and other small items that typically come into contact with babies and children. The invention provides a safe, fast and convenient way to clean such items, including those which are not suitable for cleaning or sterilizing by traditional methods, such as hand or machine washing. The device permits exposure of items to ultraviolet light, and provides a means for moving the items to insure that all surfaces of the items are exposed to UW light.  
       BACKGROUND OF THE INVENTION  
       [0002]     Babies and children often place various items, including toys and game pieces, in their mouths. They also tend to place their own hands or fingers in their mouths, and then use those hands to touch other items. Babies and children also often place the toys, pacifiers, bottles and similar items of other babies and children in their own mouths. When babies and children are sick, they can sneeze or cough onto their toys, game pieces, bottles, and pacifiers, or wipe their noses on their hands, then touch such items. In groups of two or more babies or children, such tendencies can lead to the transfer of harmful bacteria, viruses and other microorganisms from one baby or child to another. Thus, it is important to sterilize all such items before access by another child, particularly in day care centers, doctors&#39; offices, play areas, schools and other places where groups of children are given access to the same toys, games and other items. However, it often is impractical or impossible to thoroughly sterilize all such items through hand or machine washing or other methods that require immersion in water, due to the size, material and/or shapes of such items. Washing such items with a liquid also is not desirable as soaps, chemicals and other agents necessary to disinfect such items, can remain on the surface of the item and be ingested by a baby or child who places the item in his or her mouth after cleaning. Further, some items that are washable in water require significant drying time. Moreover, it is important to insure thorough and complete sterilization of such items. Heat, as from steam or microwaving, is also undesirable as it may damage softer plastics, require cool-down time before re-use, or burn the user. Metal parts found commonly in toy assemblies, such as screws and springs, make microwave activated sterilization impossible. Further, hollows and crevices in toys can retain water when washed in dishwashers, by hand washing or using steam.  
         [0003]     The present invention addresses the need for a means of sterilizing toys and other items children contact; a) without damaging the item; b) which can thoroughly and completely sterilize the item; and c) which can sterilize the items without leaving behind chemicals or other compounds which create a hazard for babies and children who will use the item after it is sterilized.  
         [0004]     The present invention attains each of these goals through the use, of a compact and convenient sterilizer which uses ultraviolet, or. “UV” light. UV light is invisible radiation having a wavelength of between 100 to 320 nm. The most effective range for sterilization is within 200 nm to 290 nm, designated the UV-C band, with a bandwidth between 250 nm and 260 nm being optimal. At this wavelength, such light is capable of inactivating and destroying a variety of bacteria, viruses, mold and other microorganisms. When UV-C light hits a microorganism, the light is absorbed by the microorganism, which is destroyed. Because the items are sterilized by light, they are not wet by, or submerged in, water, soap or chemicals. Thus, no drying is required, the items are not exposed to extreme heat and no potentially harmful chemicals or soaps are left behind on the item. Even items that are not suitable to be washed in water, such as wood, can be sterilized with UV light.  
       SUMMARY OF THE INVENTION  
       [0005]     The present invention is directed to a novel device which comprises a housing, made of material suitable to contain UV radiation, which housing encloses a removable basket or other receptacle made of a material or structure which is ‘transparent’ to UV-C radiation, through which UV light may be transmitted, for enclosing items to be sterilized, a motor or other means for turning the receptacle inside the housing, a source of UV light, a door to seal the housing and prevent the leakage of UV light and means for moving the receptacle inside the housing and to activate the UV source. When the system is activated, the motor turns the basket containing items to be sterilized. The UV light is directed through the basket and onto the items to be sterilized. As the basket is moved along a rotational axis, the items to be sterilized are continuously moved, insuring that UV light hits all surfaces of each item to be sterilized. The UV light destroys microorganisms on the surfaces of the items to be sterilized, but does not remain in or on the items. The items are removed from the device in a sterilized state. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]      FIG. 1  shows a front view of an embodiment of the invention.  
         [0007]      FIG. 2  shows an exploded view of an embodiment of the invention.  
         [0008]      FIG. 3  shows a side view of an embodiment of the invention.  
         [0009]      FIG. 4  shows a top view of an embodiment of the invention.  
         [0010]      FIG. 5  shows a longitudinal cross-sectional view of the embodiment of  FIG. 1  taken approximately along the line A-A of  FIG. 1 .  
         [0011]      FIG. 6  shows a longitudinal cross-sectional view of the embodiment of  FIG. 3  taken approximately along the line B-B of  FIG. 3 .  
         [0012]      FIG. 7  shows an embodiment of the device with the basket visible therein.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0013]     Reference will now be made in detail to the preferred embodiments of the invention, examples of which are also provided in the following description. Exemplary embodiments of this invention are described in some detail, although it will be apparent to those skilled in the relevant art that some features that are not particularly important to an understanding of the invention may not be shown for the sake of clarity.  
         [0014]     The present invention is directed to a sterilizer for small items used by babies and children. The housing of the sterilizer is constructed of material that is impervious to UV-C radiation, such as plastic. The housing is sealed by a door, which provides access inside the housing. The housing comprises a basket for placing articles to be cleaned, a UV light source, a power source, a motor for rotating such basket and a power switch. The interior of the housing is coated with UV-C material by vacuum coating or electro-coating or is made of UV-C reflective material such as polished aluminum or stainless steel, to reflect UV-C light within the unit and increase exposure of the items therein to UV-C light.  
         [0015]      FIG. 1  is a front view of a preferred embodiment of sterilizer  10  comparing a semi-circular shaped cover or dome  12 , which accommodates a circular internal basket, and a stable base  14 . Four feet  16  are located on each corner of base  14  to provide additional stability, as well as ventilation under the sterilizer  10  and to prevent scratches or markings to surfaces on which the sterilizer  10  is placed. Feet  16  are preferably made of rubber or relatively smooth plastic. Feet  16  have threaded holes extending longitudinally through their centers and are secured to the base  14  by fasteners  18 , which preferably are plastic screws, such that the head of each screw is flush with the bottom of foot  16  when fully screwed into foot  16 . Felt disks  19  are attached, preferably by glue or other suitable adhesive, to plastic screws  18  to provide additional stability and to provide additional protection to surfaces on which sterilizer  10  are placed. In  FIGS. 1 and 2 , feet  16  are shown as semi-spherical. However, any shape having flat top and bottom surfaces is suitable. Base  14  accommodates faceplate  15  which is partially semi-circular and has two notches  52  and  54 . Notch  52  receives hinge  28  which movably attaches door  24  to faceplate  15 . Handle  30  is attached to faceplate  15  at notch  54  and provides means for opening and closing door  24 . Faceplate  15  contains hole  20  through which power button  22  can be accessed. Base  14  is shaped to accommodate faceplate  15 . Faceplate  15  is shaped to accommodate door  24 . In a preferred embodiment door  24  is round. Also in a preferred embodiment, door  24  contains window  26  which is covered with transparent plastic, which filters UV-C rays. UV-C rays can be harmful to eyes and skin, but are blocked by most materials including clear plastics. Thus, window  26  prevents harmful UV-C rays from escaping sterilizer  10  while enabling a user to watch the sterilization process. In a preferred embodiment the transparency of window  26  creates a “violet light” effect when UV-C light source  50  is activated.  
         [0016]      FIG. 2  is an exploded view of the sterilizer showing the main components: door  24 , window  26 , hinge  28 , handle  30 , front plate  15  having hole  20  preferably located in a lower corner, basket collar  34 , basket  36 , base  14 , track  38 , rim  40 , back support  42 , starter  44 , ballast  46 , motor  48 ,; UV-C light source  50  and dome  12 . As seen in  FIG. 2 , base  14  comprises bottom  55 , side walls  56  and back panel  57  that further comprises lips  58 . Base  14  further comprises flanges  64 .  
         [0017]     In assembly, window  26  is fitted into door  24  and secured by lips  58 , located on both sides of window  26 . Lips  58  are pushed under grooves  60  extending along the rear edges of door  24 . Window  26  also can be secured to door  24  using readily available adhesives. Door  24  having, in one embodiment, window  26  attached therein is movably attached at one side to faceplate  15  via hinge  28 . Hinge  28  is attached at one side to door  24  using standard screws or other fasteners. Hinge  28 , attached to door  24 , and then is seated into notch  52 . Spring-loaded protrusions  27  in hinge  28  fit into holes  53  drilled into the top and bottom of notch  52 , enabling hinge  28  and door  24  to move in an arc of about 180 degrees. While the arc may be decreased, an arc of about 180 degrees allows for ease of filling, emptying, removal and replacement of basket  36  when the sterilizer  10  or basket  36  is being cleaned, serviced, filled or emptied. Handle  30  is attached to door  24  at a point on the rim of door  24  that is across from the point at which hinge  27  is attached to door  24 . Handle  30  is attached to door  24  using standard fasteners such as screws. Handle  30  comprises a spring mechanism or other locking mechanism that holds door  24  securely to faceplate  15  when the sterilizer  10  is in a closed position. Rim  40 , which preferably is made of rubber, is seated into the rear of faceplate  15  such that a seal is formed around door  24  when the sterilizer  10  is in a closed position, preventing leakage of UV-C radiation when the unit is operating. Basket collar  34  is rigidly attached to basket  36 . Basket handle  37  is movably attached to basket collar  34  such that it pivots to lie along basket collar  34  when not in use. Track  38  is fastened to the inside surface of base  14  using standard screws such that a space of about 1 inch is created between base  20  and the roof of track  38 . Power button  22  is placed through hole  20  from the internal face of faceplate  15 , such that power button  20  protrudes from the front of faceplate  15 .  
         [0018]     As can more easily be seen in  FIG. 5 , which is a longitudinal sectional view of the embodiment of  FIG. 1  taken approximately along the line A-A of  FIG. 1 , when assembled, motor  48  is attached by standard fasteners such as screws to the center of back support  42 . Sprocket  43  on motor  42  engages the ribs of well  70 , formed in the bottom of basket  36 . As also seen in  FIG. 5 , UV-C light source  50  is placed into sockets  61  fastened inside dome  12 .  
         [0019]     In a preferred embodiment, UV-C light source  50  is cylindrical, type G6T5, has wattage of 6, a base diameter of 15 mm, lamp diameter of 15 mm, is 9 inches in length, has 2 2-pin aluminum bases and is constructed of hard glass quartz. Effective sources of UV-C light are low pressure mercury discharge lamps. A preferred lamp is manufactured by Royal Philips Electronics. Another preferred lamp is manufactured by Osram Sylvania, Inc. Intensity at 1 meter using a type G6T5 bulb preferably is 16.7 uW/cm 2 . In a preferred embodiment, starting voltage of UV-C source  50  is 120 VAC @ 60 HZ, operational voltage is 120VAC @ 60 HZ, UV output is 253.7 nm @ 100 hrs. The average lamp life of a G6T5-type is 6,000 hours.  
         [0020]     As best seen in  FIG. 7 , faceplate  15 , which is attached to door  24 , window  26 , handle  30  and hinge  28  as described above, is attached by standard means such as screw means  62  to dome  12 . As seen in  FIG. 3 , in a preferred embodiment, faceplate  15  is angled toward the user, enabling the sterilizer to be accessed easily from a shelf or the floor. Housing  15  is attached to base  14  such that flanges  62  on dome  12  contact flanges  64  on base  14 . Flanges  62  and  64  receive screws to facilitate fastening of housing  15  to dome  12 .  
         [0021]     As seen in  FIG. 6 , basket  36  is slid into sterilizer  10  along track  38 . Basket  36  has paddles  66  protruding from several points of its internal wall to encourage movement of items in basket  36  when the sterilizer  10  is in use. Basket  36  has a proliferation of openings throughout to facilitate exposure of items therein to UV-C light so that sterilization takes place in an optimum amount of time. Alternatively, basket  36  is made of a transparent plastic mesh.  
         [0022]     As best seen in  FIG. 6 , wire  68  is attached to starter  44  and runs under track  38 . Wire  68  is attached at the opposite end to power button.  22 . As best seen in  FIG. 5 , starter  44  is electrically attached to ballast  46  which provides resistance to stabilize current in the circuit created when sterilizer  10  is attached to a power source via power cord  69 . In a preferred embodiment, ballast  46  is operational with 100/200VAC at 50/60 HZ.  
         [0023]     As can be seen in  FIG. 4 , in one embodiment the overall design of sterilizer  10  is compact and slightly narrower at the rear, enabling it to be placed on a shelf or counter.  
         [0024]     In operation, door  24  is opened using handle  30 , and items to be sterilized are placed into basket  36 . Door  24  is pivoted on hinge  28  into a closed position. Power button  22  is pressed, closing the electrical circuit formed by starter  44 , motor  48  and UV-C light source  50 . Motor  48  is activated and its shaft turns in a circular path, causing sprocket  43  to engage well  60 , thereby causing basket  36  to turn in a circular path. Items in basket  36  are randomly moved inside basket  36 . The items in basket  36  randomly strike paddles  66  and are further moved randomly inside basket  36 . Activation of the electrical circuit also causes UV-C light source  50  to be activated and to emit ultraviolet light in a direction toward basket  36 . As basket  36  spins, the items inside it are exposed to the UV-C light emitted from light source  50 . The random movement of the items inside basket  36  increases the likelihood that all surfaces of the items inside basket  36  are exposed to UV-C light. As the organic, or carbon based microorganisms on the surfaces of such items are exposed to the UV-C light, the molecular bonds in such microorganisms are broken, causing genetic damage and preventing such organisms from reproducing, rendering them harmless. The ability of UV-C light to disable such microorganisms in this manner is directly related to intensity of UV-C light and exposure time. In one (not shown) embodiment, power button  22  is attached to a timer which enables the cleaning cycle to proceed for a pre-set period of time. After the time period ends, UV-C light source  50  ceases emitting light and motor  48  turns off. A cleaning cycle of fifteen minutes has been found to be sufficient to insure sterilization of six small items. There could also be a relay circuit (not shown) which is preset for the appropriate sterilization cycle.  
         [0025]     What has been illustrated and described herein is a sterilizer for small items. While the invention has been illustrated and described with reference to certain preferred embodiments, the present invention is not limited thereto. In particular, the foregoing specification and embodiments are intended to be illustrative and are not to be taken as limiting. Thus, alternatives such as structural or mechanical equivalents and modifications will become apparent to those skilled in the art upon reading the foregoing description. Accordingly, such alternatives, changes, and modifications are to be considered as forming a part of the present invention insofar as they fall within the spirit and scope of the appended claims.