Patent Publication Number: US-7219816-B1

Title: Easily sealed and opened pre-filled, disposable pipette

Description:
TECHNICAL FIELD 
     The invention pertains to the general field of pipettes, and more particularly to an easily sealed and opened, pre-filled, disposable pipette that is filled with a medicinal product, used once and discarded. 
     BACKGROUND ART 
     A typical pipette consists of a slender pipe or tube that is used to transfer or measure small quantities of a liquid or a gas from one location to another. The most common type of pipette consists of a small plastic tube that widens into a bulb at the middle or the end. 
     Liquid may be sucked into the bulb and, retained therein by closing the top end of the pipette with a stopper, a person&#39;s thumb or the like. Most conventional prior art pipettes, if used as medication storage device, inherently have, the following problems: 
     1. Filling a pipette with liquid medication is difficult due to the pipette&#39;s narrow opening and the tendency of the bulb to deform if improperly handled, 
     2. After the pipette is filled any subsequent processing of the pipette is difficult, primarily because the bulb can be inadvertently deformed, thus causing the liquid therein to flow out. In general, conventional pipette designs do not include any grasping sections that allow pipettes to be conveniently handled. The bulb cannot be used as a grasping point because of its tendency to deform, and the remaining parts of a pipette are also not suitable for grasping because the mass center of a pre-filled pipette is centered on the bulb. 
     3. A conventional pre-filled pipette cannot be adequately sealed due to the handling problem described above. 
     4. Conventional sealing methods are not efficient as they require more materials and additional processes to accomplish the required seal. 
     5. Conventional sealing methods are also not reliable because the seal can be easily ruptured, causing product leakage. 
     6. Conventional means of opening the medicinal product contained within a pipette are not convenient and provide little protection for the patient. 
     The problem described in items 1, 2 and 3 have been addressed by the applicant&#39;s issued U.S. Pat. No. 6,457,612. The instant application provides a solution to the problems described in items 4, 5 and 6.
         A search of the prior art did not disclose any literature or patents that read directly on the claims of the instant invention. However, the following U.S. patents are considered related:       

     
       
         
           
               
               
               
             
               
                   
               
               
                 PATENT NO. 
                 INVENTOR 
                 ISSUED 
               
               
                   
               
             
            
               
                 6,457,612 
                 Zhang, et al 
                 1 Oct. 2002 
               
               
                 5,073,347 
                 Garren, et al 
                 17 Dec. 1991 
               
               
                 4,875,602 
                 Chickering, et al 
                 24 Oct. 1989 
               
               
                 4,563,104 
                 Saint-Amand 
                 7 Jan. 1986 
               
               
                 4,483,825 
                 Fatches 
                 20 Nov. 1984 
               
               
                   
               
            
           
         
       
     
     U.S. Pat. No. 6,457,612 discloses a pre-filled disposable pipette consisting of a hollow bulb dimensioned to enclose a medicinal product and having attached a medication transfer tube from where the pipette is filled and medicinal product released. The pipette has a primary grasping tab attached to an upper end of the bulb, a secondary grasping tab attached to each side of the tube, and a support tab also attached to each side of the tube near the lower end of the tube. The pipette can be automatically filled and sealed by a cap or heat applied foil. 
     U.S. Pat. No. 5,073,347 discloses a volumetric pipette for dispensing liquids. The pipette is formed as a unitary structure made of components which are bonded together to create a precision fluid dispensing device. The pipette includes a stem portion, which is separately formed and is bonded to a bulb portion to complete the pipette. 
     U.S. Pat. No. 4,875,602 discloses a liquid dispensing apparatus which includes a self-contained source of fluid that is normally isolated within a reservoir bulb. The bulb is deformed to initially rupture a membrane, thereby allowing the fluid to be forced through a shaft bore to saturate a tip-mounted swab. Alternatively, the membrane may be positioned intermediate two aligned sections of the shaft and is ruptured upon partial axial collapse of the sections. 
     U.S. Pat. No. 4,563,104 discloses a disposable liquid dispensing pipette which delivers an accurate and uniform drop of liquid of a given size and which incorporates an integral paddle stirrer. The device includes a dispensing tube that is connected to a flexible and resilient bulb and paddle stirrer. The open end of the tube can be made in various sizes to accommodate different drop sizes. 
     U.S. Pat. No. 4,483,825 discloses a pipette having a liquid receiving hollow generally encompassed by deformable sidewalls. The pipette further has a tapered liquid outlet extending from one end of the hollow, and a liquid inlet on the other end of the hollow, within which is located a semi-permeable filter. 
     For background purposes and as indicative of the art to which the invention is related reference may be made to the remaining cited patents. 
     
       
         
           
               
               
               
             
               
                   
               
               
                 PATENT NO. 
                 INVENTOR 
                 ISSUED 
               
               
                   
               
             
            
               
                 6,117,394 
                 Smith 
                 September 2000 
               
               
                 5,927,884 
                 Kao 
                 July 1999 
               
               
                 5,702,035 
                 Tsao 
                 December 1997 
               
               
                 4,779,768 
                 St. Amand 
                 October 1988 
               
               
                 3,951,313 
                 Coniglione 
                 April 1976 
               
               
                 3,792,699 
                 Tobin 
                 February 1974 
               
               
                 3,495,917 
                 Truhan 
                 February 1970 
               
               
                   
               
            
           
         
       
     
     DISCLOSURE OF THE INVENTION 
     The pre-filled disposable pipette disclosed herein features a simple structure for breaking the seal of a pipette, and several methods for sealing a pipette that contains a medicinal or other products which can have a consistency ranging from a liquid to a paste. In its most basic form, the inventive pipette is comprised of: 
     a) a hollow bulb containing a medicinal product and having an upper end, and a lower end that further has a substantially centered opening, 
     b) a medication transfer tube having an upper end that interfaces with the centered opening on the hollow bulb, and a lower end, 
     c) a medication fill tube having an upper end and a lower tip, 
     d) a break-away notch located between the lower end of the medication transfer tube and the upper end of the medication fill tube. When the area encompassing the notch is twisted, the medication fill tube breaks away from the medication transfer tube, thus allowing the medicinal product in the hollow bulb to be dispensed from the lower end of medication fill tube, and 
     e) means for sealing the lower tip of the medication fill tube. 
     A conventional prior art, pre-filled disposable pipette typically consists of a hollow bulb having an upper end, a lower end and is dimensioned to enclose a medicinal product. From the lower end of the bulb extends outward a medication transfer tube, from where the pipette is filled and a medicinal product released. The pipette includes a primary grasping tab attached to the upper end of the bulb, a secondary grasping tab attached to each side of the medicinal transfer tube, and a support tab also attached to each side of the tube near the lower end of the tube. The pipette is typically sealed by means of either a cap or heat-applied foil. The filled prior art pipette is not easily and efficiently sealed in terms of the manufacturing process and cost because additional material such as foil is required, as well as additional equipment and steps to cut and shape the foil to provide means for opening the medicinal product contained within the pipette. The pipette&#39;s seal is also not reliable, as it can be easily ruptured, thereby causing leakage of the medicinal product. Furthermore, the seal cannot be expediently opened since the means for removing the foil cover can be easily cleaved. 
     The inventive easily sealed and opened, pre-filled, disposable pipette provides an improvement over prior art design by adding a break-away notch between the support tab and the secondary grasping tab. By twisting the support tab with respect to the secondary grasping tab, the support tab can be easily and cleanly removed around the area encompassing the break-away notch. 
     Another improvement of the easily sealed and opened, pre-filled, disposable pipette is the sealing method. The open end of the pipette is sealed by applying sufficient heat to melt the pipette tip, then using a mechanical means to perfect the seal. 
     In view of the above disclosure, the primary object of the invention is to produce an easily manipulated pipette that can be easily and expediently sealed and opened. 
     Another object of the invention is to produce a pipette with an opening means that provides dexterity and protection for the patient. 
     Still another object of the invention is to produce a pipette that can have a reliable seal, thus reducing the possibility of medicinal product leakage. 
     Yet another object of the invention is to produce a pipette that can be readily and conveniently handled and maneuvered, to be automatically filled and to accommodate the pipette sealing methods. 
     These and other objects and advantages of the present invention will become apparent from the subsequent detailed description of the preferred embodiment and the appended claims taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side elevational view of the pre-filled disposable pipette showing the relative locations of the elements that comprise the pipette. 
         FIG. 2  is a top plan view of the pre-filled disposable pipette. 
         FIG. 3  is a partial elevational and cross-sectional view of a lower tip sealing means that utilizes a heat flow across the lower tip of a rotating pipette to melt and seal the open end due to the surface tension caused by the heat. 
         FIG. 4  is a partial elevational and cross-sectional view of a lower tip sealing means that utilizes heat flow across the lower tip of a rotating pipette to melt the tip and thereafter using an ambient temperature device to crimp the melted tip and seal the lower tip. 
         FIG. 5  is a partial elevational and cross-sectional view of a lower tip sealing means that utilizes heat flow across the sides of the lower tip of the pipette to melt the tip and thereafter using an ambient temperature clamp to crimp the two sides of the melted tip and seal the lower tip. 
         FIG. 6  is a partial elevational and cross-sectional view of a lower tip sealing means that utilizes a heated element to melt and seal the lower tip. 
         FIG. 7  is a partial elevational and cross-sectional view of a lower tip sealing means that utilizes a high-temperature, dual-element device that melts, crimps and seals the lower tip. 
         FIG. 8  is a partial elevational and cross-sectional view of a lower tip end sealing means that utilizes a heated element to melt the lower tip of the pipette and thereafter using an ambient-temperature device to crimp, shape and seal the lower tip. 
         FIG. 9  is a partial elevational and cross-sectional view of a lower tip sealing means that utilizes a heated element to melt the lower tip of the pipette and thereafter using an ambient-temperature, dual-element device to crimp and seal the lower tip. 
     
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     The best mode for carrying out the invention is presented in terms of a preferred embodiment for an easily sealed and opened, pre-filled disposable pipette  10  (hereinafter “pipette  10 ”). The pipette  10  is designed to contain and release a medicinal product selected from a group consisting but not limited to a liquid, an aqueous solution, an oil, a solvent, an emulsion, a cream, an ointment, a lotion, a paste, a jelly and a balm. 
     As shown in  FIGS. 1 and 2 , the pipette  10  is comprised of several major elements. A hollow bulb  12  that has an upper end  14  and a lower end  16 , which further has a substantially centered opening  18 . The preferred cross section of the hollow bulb is round, however other shapes can also be used. A medication transfer tube  24  that has an upper end  26  and a lower end  28 , with the upper end  26  interfacing with the centered opening  18  on the hollow bulb  12 . The internal diameter of the transfer tube  24  is at least two times smaller than the internal diameter of the hollow bulb  12 . A medication fill tube  32  that has an upper end  34  and a lower tip  36 . A break-away notch  40  that is located between the lower end  28  of the medication transfer tube  24  and the upper end  34  of the medication fill tube  32 . The break-away notch  40  when twisted, causes the medication fill tube  32  to break off from the medication transfer tube  24 , thus allowing the medication located within the hollow bulb  12  to be released from the lower end  28  of the medication transfer tube  24 . The final major element of the pipette  10  is a means  86  for sealing the lower tip  36  of the medication fill tube  32 , as shown in  FIGS. 3–9 . 
     The pipette  10 , as shown in  FIGS. 1 and 2 , further comprises a primary grasping tab  46 . The tab  46  is shaped and dimensioned to allow the tab to be easily grasped by two fingers, thus permitting the pipette  10  to be carried or held without contacting the sensitive hollow bulb  12  which is filled with the medicinal product. 
     The tab  46  has an upper edge  48  and a lower edge  50 , which centrally interfaces with and conforms to the upper end  14  of the hollow bulb  12 . As also shown in  FIGS. 1 and 2 , the pipette further comprises a secondary grasping tab  54  having a first section  56  and a second section  62 , and a support tab  70  having a first section  72  and a second section  80 . The first section  56  of the secondary grasping tab  54  has an outer edge  58  and an inner edge  60 , which interfaces with a first side of the medication transfer tube  24 . The second section  62  of the tab  54  has an outer edge  64  and an inner edge  66 , which interfaces with a second side of the medication transfer tube  24 . The first section  72  of the support tab  70  has an outer edge  74  and an inner edge  76 , which interfaces with a first side of the medication fill tube  32 . The second section  80  of the support tab  70  has an outer edge  82  and an inner edge  84 , which interfaces with a second side of the medication fill tube  32 . 
     As shown in  FIG. 1 , the pipette  10  can further include a flat finger-grasping area  20  that is located on opposite sides of the hollow bulb  12 . The flat area  20  allows the pipette  10  to be conveniently held when dispensing the medicinal product. 
     The hollow bulb  12 , the medication transfer tube  24 , the medication fill tube  32 , the break-away notch  40 , the primary grasping tab  46 , the secondary grasping tab  54  and the support tab  70  are all integrally molded of a thermoplastic. The type of thermoplastic is selected from a group consisting of: polycarbonate, polyethylene, polyester, polystyrene, polypropylene, polysulfone, polyurethane and ethylene-vinyl-acetate. Additionally, the thermoplastic can be transparent or color tinted to indicate the type or the quantity of medication located within the hollow bulb  12 . 
     As shown in  FIGS. 3–9 , several means  86  are disclosed by which the lower tip  36  of the medication fill tube  32  can be sealed. 
     The first means for sealing the medication fill tube&#39;s lower tip  36  is comprised of applying a heat flow  90  to the lower tip  36 , which is being rotated by a tip rotating means  88  to melt the tip, as shown in  FIG. 3A . The surface tension caused by the melted tip then seals the tip  36 , as shown in  FIG. 3B . 
     The second means for sealing the medication fill tube&#39;s lower tip  36  is comprised of applying a heat flow  90  to the lower tip  36 , which is being rotated by a tip rotating means  88 , to melt the tip, as shown in  FIG. 4A . An ambient temperature device  92  having an opening is subsequently pressed over the melted tip to seal the tip  36 , as shown in  FIG. 4B , to produce a sealed tip  36 , as shown in  FIG. 4C . 
     The third means for sealing the medication fill tube&#39;s lower tip  36  is comprised of applying a heat flow  90  to the lower tip  36  to melt the tip, as shown in  FIG. 5A . An ambient temperature clamp  94 , as shown in  FIG. 5B , is then adjusted to clamp the melted tip and seal the tip  36 , as shown in  FIG. 5C . 
     The fourth means for sealing the medication fill tube&#39;s lower tip  36  is comprised of inserting over an ambient temperature lower tip  36 , as shown in  FIG. 6A , a heated element  96 , as shown in  FIG. 6B , that melts and crimps the tip. After the heated element  96  is removed, a sealed tip  36  is produced, as shown in  FIG. 6C . 
     The fifth means of sealing the medication fill tube&#39;s lower tip  36  is comprised of applying to an ambient temperature lower tip, as shown in  FIG. 7A , a high-temperature, dual-element device  98 , as shown in  FIG. 7B , that melts and crimps the lower tip  36  to produce a sealed lower tip  36 , as shown in  FIG. 7C . 
     The sixth means for sealing the medication fill tube&#39;s lower tip  36  is comprised of placing a heated element  96  over the lower tip  36  to melt the tip, as shown in  FIG. 8A . An ambient temperature device  92 , as shown in  FIG. 8B , is then placed over the melted lower tip  36  that crimps and seals the lower tip  36  to produce a sealed lower tip  36 , as shown in  FIG. 8C . 
     The seventh and final means for sealing the medication fill tube&#39;s lower tip  36  utilizes a heated element  96  that is placed over the lower tip  36 , as shown in  FIG. 9A , to melt the lower tip. Thereafter, an ambient-temperature, dual-element device  100 , as shown in  FIG. 9B , is placed over the melted tip  36  that crimps and seals the lower tip  36  to produce a sealed lower tip  36 , as shown in  FIG. 9C . 
     While the invention has been described in complete detail and pictorially shown in the accompanying drawings it is not to be limited to such details, since many changes and modifications may be made to the invention without departing from the spirit and the scope thereof. For example, the pre-filled disposable pipette  10  can be made in various sizes to accommodate various quantities and consistencies of medicinal and similar products. Also, while several means for sealing the lower tip  36  of the medication fill tube  32  have been disclosed, other sealing means can be utilized with equal effectiveness. Additionally, the ambient temperature device  92  and the heated element  96  can be designed to produce various geometric sealing shapes. Hence, it is described to cover any and all modifications and forms, which may come within the language and scope of the claims.