Abstract:
An apparatus for sterilizing a medical device includes an ozone generator; and a tubular shaped reflecting screen. The screen has two ends, in which the screen is connected at a first end to a source of oxygen containing gas and at a second end to a sterilizing tip. The medical device to be sterilized is connected to the sterilizing tip. Methods of using the device include joining a source of oxygen containing gas to an inlet; attaching a medical device to be sterilized to the sterilizing tip; energizing the ozone generator with electric power to generate an electric corona; and passing an oxygen containing gas through the electric corona so as to generate ozone, thereby sterilizing the medical device.

Description:
PRIORITY INFORMATION  
       [0001]    This is a divisional of U.S. patent application Ser. o. 09/317,362 filed on May 24, 1999, which is a continuation of U.S. patent application Ser. No. 08/956,709, filed on Oct. 23, 1997 and issued as U.S. Pat. No. 5,911,957. 
     
    
     
       BACKGROUND  
         [0002]    1. Field of the Invention  
           [0003]    The present invention generally relates to an ozone generator, and specifically to an Ozone generator comprised of a discharge means and a reflecting screen capable of sterilizing various articles.  
           [0004]    2. Description of the Related Art  
           [0005]    Ozone is a powerful oxidizing agent that has many industrial and household uses. Ozone effectively kills bacteria, inhibits fungal growth, and inactivates many viruses, cysts, and spores. In addition, soaps, oils, and chloramines can be rendered environmentally safe by ozone treatment. The antiseptic properties of ozone are useful for water purification, room sanitation, equipment sterilization, and food preservation.  
           [0006]    There are several known methods for producing ozone from air or other oxygen-containing gases. A number of these processes generate ozone by passing an oxygen-containing gas between two electrodes, separated by a dielectric material-the oxygen is converted to ozone as it travels through the electrical corona. Ozone has a half-life of only about 22 minutes at ambient temperatures, and at higher temperatures the rate of ozone decay is accelerated. An efficient ozone generator should, therefore, produce a high concentration of ozone without generating appreciable heat.  
           [0007]    To this aim, several modifications on the basic corona discharge ozone generator have been developed. U.S. Pat. No. 5,409,673 relates to an ozone generator characterized by an outer electrode overlying a portion of a dielectric tube filled with a mass of helical windings which serves as an inner electrode. Similarly, U.S. Pat. No. 5,554,344 teaches the enhancement of ozone production by employing electrodes with a jagged surface while U.S. Pat. No. 4,981,656 teaches that an electrode of polygonal shape provides uniform gas discharge at low electrical voltages. Furthermore, with regard to heat dissipation, U.S. Pat. No. 4,770,858 teaches the benefits of coating the surface of a dielectric tube with non-conductive particles of inorganic material.  
           [0008]    Despite the numerous beneficial applications for ozone and repeated attempts in the prior art to invent an efficient ozone generator, such a discovery has not yet occurred. The failure of the prior art to provide an efficient ozone generator can be attributed to three persistent problems: improperly aligned electrodes, accumulation of heat generated by the electrical discharge, and the lack of a means to direct freshly made ozone away from the apparatus to a site intended for treatment. The need for a simple and compact apparatus which efficiently produces and rapidly disperses ozone without accumulating an appreciable amount of heat is manifest.  
         SUMMARY  
         [0009]    The present invention discloses a new apparatus and method for producing ozone by electrical silent discharge. As disclosed herein, an ozone generator, is comprised of a silent discharge means joined to a reflecting shield. The discharge means comprises a rough-surfaced dielectric element of rectangular shape, a first electrode, and a second electrode. The dielectric element is sandwiched between the first electrode and the second electrode and both electrodes are connected to a high frequency (HF) converter.  
           [0010]    The first electrode is comprised of a plurality of helical windings that contact a plurality of flanges on the dielectric element and the second electrode is comprised of an electrically conductive coating which overlies the rough surface of the dielectric element. The rectangular shape of the dielectric element facilitates the alignment of the electrodes, and the flanges maintain this aligned position. The fusion of the second electrode with the surface of the dielectric element significantly improves ozone recovery by rapidly dispersing heat as it is generated, and the reflecting screen directs accumulated ozone away from the ozone generator and toward an intended site for treatment. 
       
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0011]    [0011]FIG. 1 is a sectional side view of a first embodiment of a silent discharge means attached to a HF converter, taken at arrow  1  of FIG. 2;  
         [0012]    [0012]FIG. 2 is a cross-sectional view of the first embodiment of the silent discharge means.  
         [0013]    [0013]FIG. 3 is a cross-sectional view of a second embodiment of the discharge means;  
         [0014]    [0014]FIG. 4 is a perspective view of a first embodiment of an ozone generator according to the present invention (without reflecting screen);  
         [0015]    [0015]FIG. 5 is a sectional view of a second embodiment of the ozone generator according to the present invention;  
         [0016]    [0016]FIG. 6 is a sectional view of a third embodiment of the ozone generator according to the present invention;  
         [0017]    [0017]FIG. 7 is a sectional view of a fourth embodiment of the ozone generator according to the present invention; and  
         [0018]    [0018]FIG. 8 is a sectional view of a fifth embodiment of the ozone generator according to the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0019]    The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may be embodied in many different forms, however, and should not be construed as limited to the embodiments set forth within. Applicants provide these embodiments so that this disclosure will be thorough and complete, and willfully convey the scope of the invention to those skilled in the art.  
         [0020]    As shown in FIGS.  1 - 8 , an ozone generator is comprised of a discharge means  24  optionally connected to a reflecting screen  22 . The discharge means  24  is connected to a high frequency converter (HF converter)  58  which is in turn connected to a power supply  20 . The power supply  20  is either a storage battery (FIG. 6, 8) or normal line current from an electrical network ( 110  or  220  volts) (FIG. 4, 5,  7 ). Optional electrical leads  28  may be used to connect the high frequency converter  58  to the discharge means  24  and the power supply  20 . FIGS.  1 - 3  reveal that the discharge means  24  is comprised of a rough-surfaced dielectric element  34  of rectangular shape, a central aperture  44 , a first electrode  32 , a second electrode  36 , and a plurality of flanges  30 . The electrode  32  and  36  are attached to the high frequency (HF) converter  58 , which is in turn attached to the power supply  20 . The power supply is either a battery or line current from an electrical network.  
         [0021]    In a first embodiment of the discharge means  24 , illustrated in FIGS. 1 and 2, the first electrode  32  is comprised of a plurality of helical windings that are mounted inside the central aperture  44  in an aligned position. Alignment of the first electrode  32  with respect to the central aperture  44 , dielectric element  34 , and the second electrode  36  is necessary to ensure uniform discharge at low voltages and to reduce the accumulation of heat at the dielectric element  34  and the electrodes  32  and  36 . As used in this disclosure, the intended meaning of the word alignment and derivatives thereof encompasses the position of the first electrode  32  with respect to the central aperture  44 , the dielectric element  34 , and the placement of the first electrode  32  in a manner that maintains a constant distance of separation between the electrodes  32  and  36  along the entire length of the discharge means  24 . The rectangular shape of the dielectric element  34  facilitates the determination of the position of the alignment of the first electrode  32 , and flanges  30  hold the first electrode  32  in the properly aligned position. The helical windings of the first electrode  32  comprise a spiral shape. The first electrode is held in position inside the dielectric element  34  through the elastic nature or spring-like behavior of the spiral. The first electrode  32  is generally the same length as the dielectric element  34 , although a first electrode  32  of any size can be constructed and mounted within a larger-sized dielectric element  34 . The first electrode  32  of the first embodiment of the discharge means  24  may have 1 winding per cm to 100 windings per cm, or more desirably 2 windings per cm to 50 windings per cm, or preferably 2 windings per cm to 20 windings per cm. Similarly, the diameter of the filament used to construct the helical windings for this embodiment may include 0.001 mm to 1 mm, or more desirably 0.01 mm to 0.5 mm, or preferably 0.1 mm to 0.14 mm. The helical windings of the first electrode  32  can be made from tungsten, nickel-chromium alloy, molybdenum, or other suitable metals. aperture can have a diameter of 0.1 mm 20 mm, more preferably 1 mm to 10 mm, and most preferably from 2 mm to 6 mm.  
         [0022]    The dielectric element  34  has a rough surface which serves as the foundation for the second electrode  36 , once the dielectric element  34  is overlaid with the electrically conductive coating serving as the second electrode  36 . The rough surface on the dielectric element  34  can be made by sanding, chemical treatment, or by embedding the surface with electrically non-conductive particles. Particles suitable for embedding the surface of the dielectric element are glass or ceramic, but many equivalent particles would be known by one of skill in the art. Furthermore, there are many ways to create a dielectric element  34  with a rough surface, and any person of skill in the art could develop alternative means to fulfill this purpose of the invention. Discharge at low voltages is improved by the rough surface of the second electrode  36 , and the intimate association of the second electrode  36  with the dielectric element  34  enables the rapid dispersion of heat generated by the discharge means  24 .  
         [0023]    The construction of the first embodiment of the discharge means  24  can be used to guide one of skill in the art to make and use the second embodiment of the discharge means  24 , illustrated in FIG. 3. In the second embodiment, the first electrode  32  spirals around the outside of the dielectric element  34 , and the dielectric element  34  has a central aperture  44  with a rough interior surface. Furthermore, the electrically conductive coating of the second electrode  36  overlies the rough surface inside the central aperture  44 . The first electrode  32  is aligned with respect to the central aperture  44  and the second electrode  36 , and flanges secure the first electrode  32  to the dielectric element  34  in the aligned position. The first electrode  32  of the second embodiment of the discharge means  24  may have 1 winding per cm to 100 windings per cm, or more desirably 2 windings per cm to 50 windings per cm, or preferably 2 windings per cm to 20 windings per cm. Similarly, the filament used to construct the helical windings for this embodiment has a diameter of 0.001 mm.  
         [0024]    The flanges  30  which hold the first electrode  32  in an aligned position may be part of a single-piece dielectric element  34  or, alternatively, may be comprised of a material different than the dielectric element  34  and attached to the dielectric element  34  by conventional methods. The dimensions of the flanges  30  and their spacing within the central aperture  44  may depend on the type of ozone generator and its intended application. The dielectric element  34  may contain from 4 to 20 flanges  30 , or desirably 4 to 10 flanges  30 , or preferably 4 to 6 flanges  30 .  
         [0025]    The second electrode  36  of the first embodiment of the discharge means  24  comprises an electrically conductive coating that overlies the rough outer surface of the dielectric element  34 . Suitable electrically conductive coatings include copper, silver, and aluminum, although one of skill in the art would be able to develop and/or use many equivalent coatings to fulfill the intended purpose of this element of the present invention. The electrically conductive coating can be applied by being sprayed or chemically deposited to a thickness of 0.1 microns to 100 microns or more desirably from 0.5 microns to 50 microns or preferably from 2 to 10 microns. The second electrode  36  preferably spans the entire length of the dielectric element  34 , or alternatively, may overlay only a portion of the dielectric element  34 .  
         [0026]    The dielectric element  34  can be made from ceramic, but it is within the skill of anyone in the art to manufacture a dielectric element from many other suitable materials such as glass or PYREX. Alternatively, the surface of the dielectric element  34  facing the first electrode  32  can be a composite structure constructed of materials having different dielectric permeability and porosity such as ceramic and glass fiber. The thickness of the dielectric element  34  and the dimensions of the central aperture  44  may vary according to the apparatus and intended application, but, in general, the electrodes  32  and  36  are separated by a dielectric element  34  having a thickness of 0.01 mm to 10 mm or, more desirably, 0.05 mm to 2 mm or preferably 0.1 mm to 0.7 mm, and the central to 1 mm or more desirably 0.01 mm to 0.5 mm, or preferably 0.1 mm to 0.14 mm. The helical windings of the first electrode  32  may be made from tungsten, nickel-chromium alloy, molybdenum, or other suitable metals.  
         [0027]    The fabrication of reflecting screens  22  to accompany the embodiments illustrated in FIGS.  5 - 8  can be accomplished through routine experimentation by one of skill in the art given the disclosure that follows. Reflecting screens  22  are generally made from plastic or metal, but they can also be constructed from many other materials known to those of skill in the art. In FIG. 5, the reflecting screen  22  is a parabolic shape, and the dielectric element  34  of the discharge means  24  is joined to the reflecting screen  22  by a plurality of mounting brackets  26 . Mounting brackets  26  can include many types of connectors whose compositions are frequently made of plastic but can be comprised of any other insulating material. By placing the discharge means  24  within the focus of the parabola of the reflecting screen  22 , the flow of ozone can be directed to a site intended for sterilization.  
         [0028]    [0028]FIG. 4 shows a first embodiment of the ozone generator in which the discharge means  24  is enclosed within a discharge housing  54 . A switch  48  is connected to a high frequency converter  58  that joins to the power supply  20  and the discharge means  24 . In the embodiment shown in FIG. 4, the power supply  20  is line current from an electrical network. A light emitting diode  50  is also connected to the high frequency converter  58  and indicates the operation of the ozone generator. A source of oxygen can be attached to an inlet  62  SO that ozone can be generated as the oxygen passes through the discharge means  24 . Alternatively, the inlet  62  can be attached directly to the dielectric element  34  when using an embodiment of the invention with a hollow dielectric element, such as one with an internal electrode  32 . The ozone exits the ozone generator through a sterilizing tip  64  which is constructed so that a variety of objects can be attached and sterilized. Objects which can be attached to the sterilizing tip of this embodiment include catheters, tubing, needles, bottles, and syringes. The sterilization of many other items can be achieved by this embodiment and the sterilization tip  64  can be modified by one of skill in the art to accommodate a multitude of medical devices.  
         [0029]    Alternatively, as shown in FIG. 5 (embodiment 2), mounting brackets  26  and a protective shield  38  secure the discharge means  24  to a reflecting screen  22  shaped like a lid to a container. By placing this embodiment of the ozone generator over a matching container, items placed inside the container can be sterilized. According to this aspect of the present invention, an upper compartment  56  of the ozone generator houses a switch  48  joined to the timer  46 , a light emitting diode  50 , and a high frequency converter  58  (shown in phantom lines) joining the power source  20  and the discharge means  24 . In this case, the power source is line current from an electrical network. The discharge means  24  is mounted in a lower compartment  60  of the ozone generator, and the reflecting screen  22  forms a barrier between the two compartments. By opening the switch  48 , the timer  46  is set, and current from the power supply  20  is transferred through the high frequency converter  58  to the electrodes  32  and  36  and the light emitting diode  50 . The light emitting diode indicates that the ozone generator is in operation. When the set time expires, the current to the high frequency converter  58 , the electrodes  32  and  36 , and the light emitting diode  50  is removed.  
         [0030]    The ozone generator illustrated in FIG. 6 is constructed similarly to the embodiment shown in FIG. 5 but takes the shape of a clothes hanger and provides a means to sterilize articles of clothing. As described above, the power supply  20  (shown in phantom lines), switch  48  (not shown), timer  46  (shown in phantom lines), high frequency converter  58 , and light emitting diode  50  are isolated from the discharge means  24  by a barrier created by the reflecting screen  22 . In this case, the power supply  20  is a battery.  
         [0031]    Although the embodiment set forth in FIG. 7 is fabricated in much the same manner as the ozone generators described above, an adapter  52  attached to the high frequency converter  58  enables a user to draw current directly from an electrical outlet. A photo-cell  51  allows for automatic on/off switching depending on the light level. For example, the ozone generator can be set to operate automatically at night. The ozone generator pictured in FIG. 7 provides an efficient and economical means to deodorize or sanitize a room.  
         [0032]    The apparatus shown in FIG. 8 can be used to deodorize shoes. This ozone generator is constructed in the same manner as the embodiments shown in FIGS.  5 - 7 , but it is shaped so that the apparatus can be placed in a shoe.  
         [0033]    Many modifications and other embodiments of the invention will come to the mind of one skilled in the art having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed, and that modifications and embodiments are intended to be included within the scope of the appended claims.