Abstract:
This invention presents a syringe disposal unit for disposal of used disposable syringe needle assemblies of a reusable syringe. The syringe disposal includes a container having an interior for receiving a needle assembly of a reusable syringe. The needle assembly is removable from a syringe body of the reusable syringe. The container also has a through-hole through which the needle assembly can enter the interior. The syringe disposal also includes a needle base latch movable between an engaging position and a disengaging position. When the needle assembly is positioned in the through-hole the needle base latch contacts the needle assembly in the engaging position in such a way that the needle base latch prevents the needle assembly from rotating relative to the container, while the needle base latch does not contact the needle assembly in the disengaging position in such a manner that the needle base latch does not prevent the needle base from rotating relative to the container.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    Not Applicable. 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not Applicable. 
       APPENDIX 
       [0003]    Not Applicable. 
       FIELD OF THE INVENTION 
       [0004]    This invention generally relates to disposal units for safely disposing of used medical instruments and, more particularly, to a syringe disposal unit for safely disposing of used syringe needles of a reusable or multi-dose syringe. 
       BACKGROUND OF THE INVENTION 
       [0005]    Many patients must administer multiple doses of medication daily. Reusable or multi-dose injectors, such as reusable syringes or pen-type injectors, have been widely used for daily administration of medication. However, needles, after a use on a patient, become contaminated and create a hazard for anyone that may handle them following their use because of the chance of being accidentally stuck by these contaminated needles. In addition, the contaminated needles may become a deadly transmitter of infectious diseases, such as Acquired Immune Deficiency Syndrome (AIDS), hepatitis or the like. Accordingly, the used needle must be removed from the multi-dose syringe or pen-type injector, and then safely disposed of in a specially designed container in order to prevent accidental transmittal of infectious diseases, or intentional and/or illegal needle reuse. The containers are then collected and discharged at a separated collection point for ultimate disposal of the needles. 
         [0006]    Multi-dose syringes or pen-type injectors include a syringe body for storing the medication, and a needle assembly for transferring the medication via a needle. Needle assemblies usually include a needle, and a needle base that can be mounted onto the syringe body. The needle and needle base may be integrally formed. In many multi-dose syringe designs, needle bases have a threaded portion that can mesh with a threaded portion of the syringe body so that the needle assembly can be screwed to and unscrewed from the syringe body. 
         [0007]    Syringe disposal containers are known and examples of such containers are shown in the following specifications: U.S. Pat. No. 6,250,465, U.S. Pat. No. 6,142,303, and U.S. Pat. No. 5,848,692. These containers employ designs that allow syringes to be placed within the container while preventing them from being accidentally or intentionally removed out of the containers. However, these containers are all designed for disposal of used syringes as a whole. Accordingly, these containers are not specifically suitable for disposal of needle assemblies of reusable syringes where the used needle assemblies must be removed from the reusable syringes. 
         [0008]    Examples of syringe containers especially designed for disposal of used needle assemblies removed from the reusable syringes are shown in U.S. Pat. No. 6,253,916, U.S. Pat. No. 6,247,592, U.S. Pat. No. 6,024,216, U.S. Pat. No. 5,829,588, and U.S. Pat. No. 5,603,404. These designs employ notches, slots or gear-like teeth that can engage with the needle base, preventing it from rotating so that the needle assembly can be unscrewed from the syringe body by twisting the syringe body portion. However, the needle assemblies removed from the syringe body may be stuck with the notches, slots or teeth. Designs shown in U.S. Pat. No. 6,971,516 and U.S. Pat. No. 6,923,318 employ ribs formed on the inner surface of the openings to prevent the needle base from rotating. However, these designs cannot be used for needle assemblies in general. In other words, they can only be used for needle bases with specific diameters, and specific patterns of grooves formed on the outer surface thereof. In addition, in designs shown in U.S. Pat. No. 6,062,001 and U.S. Pat. No. 5,857,569, parts for gripping the needle base are made of flexible material so that the removed needle assemblies can only pass through the openings by being forcedly pushed down therethrough. 
         [0009]    General problem with the known disposal containers is that it is difficult to provide a container that is easy to use to remove used needle assemblies from the reusable syringe and to safely dispose of them therein. 
       SUMMARY OF THE INVENTION 
       [0010]    Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and it is an object of the present invention to provide a syringe disposal unit that can be used with various reusable syringe designs. It is another object of the present invention to provide a syringe disposal unit that can be easily used to remove used needle assemblies from the reusable syringe and to safely dispose of them therein. 
         [0011]    To achieve the above object, according to the present invention, there is provided a syringe disposal unit for disposal of used disposable needle assemblies of a reusable syringe. The syringe disposal unit includes a container having an interior space for receiving a needle assembly of a reusable syringe, which needle assembly includes a needle and a needle base and is removably screwed to a syringe body of the reusable syringe. The container has a through-hole through which the needle assembly can enter the interior. The syringe disposal unit also includes a needle base latch that is movable between an engaging position and a disengaging position. The needle base latch has a contact surface. When the needle assembly is positioned in the through-hole, the contact surface contacts the needle assembly in the engaging position in such a way that the needle base latch prevents the needle assembly from rotating. In the disengaging position the contact surface does not contact the needle assembly. 
         [0012]    In a preferred embodiment, the syringe disposal unit according to the present invention can also include a controller operatively connected with the needle base latch for moving the needle base latch between the engaging position and the disengaging position. In a preferred embodiment, the controller can be a push button. Preferably, when the push button is pressed the needle base latch is moved to the engaging position, and when the push button is released the needle base latch is moved to the disengaging position. 
         [0013]    Additionally or alternatively, in a preferred embodiment, the needle base latch can be biased toward the disengaging position. Additionally or alternatively, the needle base latch can preferably have a ridge or groove in the contact surface. 
         [0014]    In a preferred embodiment, the syringe disposal unit according to the present invention can include a cover movable between an opening position and a closing position. In the closing position the cover covers the through-hole, and in the opening position the cover does not cover the through-hole. In a preferred embodiment, the cover is slidingly movable between the opening position and the closing position. Preferably, the syringe disposal unit can also include a cover latch for releasably locking the cover in the opening position. Additionally or alternatively, the syringe disposal unit can include a cover latch for releasably locking the cover in the closing position. Additionally or alternatively, in a preferred embodiment, the cover can have an arrow pointing toward the opening position. Additionally or alternatively, the cover can be biased toward the closing position. 
         [0015]    In a preferred embodiment, the syringe disposal unit according to the present invention can also include a needle assembly holder movable between a holding position and a releasing position. In the holding position the needle assembly holder prevents the needle assembly from passing through the through-hole. In the releasing position the needle assembly holder allows the needle assembly to pass through the through-hole. In a preferred embodiment, the needle assembly holder is slidingly movable between the holding position and the releasing position. In a preferred embodiment, the syringe disposal unit can also include a controller operatively connected with the needle assembly holder for moving the needle assembly holder between the holding position and the releasing position. Additionally or alternatively, the needle assembly holder can be biased toward the holding position. 
         [0016]    In a preferred embodiment, the needle base latch can be designed in such a way that the needle base latch is in the disengaging position when the needle assembly holder is in the holding position, and the needle assembly holder is in the releasing position when the needle base latch is in the engaging position. 
         [0017]    In a preferred embodiment, the through-hole can be sized so as to provide a small clearance between the needle assembly and the inner wall of the through-hole. Additionally or alternatively, the through-hole can be sized such that the through-hole prevents the syringe body from passing therethrough while allowing the needle assembly to pass therethrough. 
         [0018]    In a preferred embodiment, the interior can be sized to receive a plurality of the needle assemblies. Preferably, the container can have a viewing window. In a preferred embodiment, the syringe disposal unit is portable. 
         [0019]    In a preferred embodiment, the container can include a top portion, a sidewall portion, and a bottom portion. The top portion is preferably fixedly attached to the sidewall portion, and the sidewall portion is preferably integrally formed with the bottom portion. 
         [0020]    Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]    The above and other objects and features of the present invention will become apparent from the following description of preferred embodiments given in conjunction with the accompanying drawings, in which: 
           [0022]      FIG. 1  is a perspective view of an example of reusable or multi-dose syringe or pen-type injectors for which a syringe disposal unit according to the present invention can be used. 
           [0023]      FIG. 2  is a perspective view of an embodiment of a syringe disposal unit according to the present invention. 
           [0024]      FIG. 3  is a top view of the syringe disposal unit of  FIG. 2  where a sliding cover is in a closing position. 
           [0025]      FIG. 4  is a top view of the syringe disposal unit of  FIG. 2  where the sliding cover is in an opening position such that a through-hole of the syringe disposal unit can be seen. 
           [0026]      FIG. 5  is a perspective view of the syringe disposal unit of  FIG. 2  with the sliding cover in the opening position, where a syringe is placed such that the disposable needle assembly of the syringe is positioned within the through-hole of the syringe disposal unit. 
           [0027]      FIG. 6  is a top view of the syringe disposal unit of  FIG. 2  where a push button is pressed and a needle base latch is in an engaging position where the needle base latch protrudes out of the inner wall of the through-hole toward the center thereof, with the sliding cover in the opening position. 
           [0028]      FIG. 7  is a top view of an embodiment of a syringe disposal unit according to the present invention, with a sliding cover in an opening position, with a push button released, and with a needle assembly holder in a holding position where the needle assembly holder protrudes out of the inner wall of the through-hole toward the center thereof. 
           [0029]      FIG. 8  is a perspective view of the syringe disposal unit of  FIG. 7  where a disposable needle assembly is removed from the syringe and held in the through-hole of the syringe disposal unit. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0030]    Shown in  FIG. 1  is an example of reusable or multi-dose syringes or pen-type injectors for which a syringe disposal unit accordingly to the present invention can be used. The syringe  2  has a syringe body  22  providing an interior chamber for storing multi-dose fluid medication therein. The syringe  2  also has a disposable needle assembly  24  attached to the syringe body  22  so as to enclose the interior chamber. The disposable needle assembly  24  has a hollow needle  242 , and a needle base  244  holding and securing the hollow needle  242  that extends therethrough in a longitudinal direction. The hollow needle  242  may be integrally formed with the needle base  244 . The needle base  244  is usually smaller than the syringe body  22  in diameter as shown. 
         [0031]    The needle base  244  has a threaded inner surface  246  as shown in  FIG. 8 . The syringe body  22  has a threaded outer surface (not shown) at its end portion, which can engage with the threaded inner surface  246  of the needle base  244 . Alternatively, it may also be possible that the needle base  244  has a threaded outer surface at its end portion that can engage with a threaded inner surface of the syringe body  22 . In this way, the disposable needle assembly  24  can be removably screwed to the syringe body  22 . After using the syringe  2 , a user can unscrew and remove the disposable needle assembly  24  from the syringe body  22  by twisting one of the syringe body  22  and the needle assembly  24  while holding the other. The disposable needle assembly  24  can also have a protective needle cap (not shown) that can be removably attached to the needle base  244  so as to cover and protect the hollow needle  242  when not used. 
         [0032]      FIG. 2  shows an embodiment of a syringe disposal unit  4  according to the present invention, which can be used for the syringe  2  as shown in  FIG. 1 . The syringe disposal unit  4  has a container including a bottom portion  41 , a sidewall portion  42 , and a top portion  44 . The bottom portion  41  and the sidewall portion  42  together provide an interior space therein for accommodating the disposable needle assemblies  24  that have been removed from the syringe body  22 . The top portion  44  of the syringe disposal unit  4  is attached on to the sidewall portion  42  so as to enclose the interior space. The top portion  44  has a through-hole  442 , as shown in  FIG. 4 , for providing access to the interior space of the syringe disposal unit  4  for disposing of used disposable needle assemblies  24 . The interior space is large enough to accommodate a number of disposable needle assemblies  24 . The interior space can preferably accommodate thirty disposable needle assemblies  24 . The interior space can be designed to accommodate a larger number of disposable needle assemblies  24 , for example sixty or ninety disposable needle assemblies  24 . However, preferably, the overall size of the syringe disposal unit  4  is small enough so that the syringe disposal unit  4  can be portable. The bottom portion  41 , the sidewall portion  42 , and the top portion  44  are all preferably made of puncture resistant and leak-proof material. 
         [0033]    The bottom portion  41  and the sidewall portion  42  are preferably integrally formed. The top portion  44  is preferably fixedly attached on to the sidewall portion  42  such that home users usually cannot detach the top portion  44  from the other portions  41 ,  42 . This promotes the integrity of the syringe disposal unit  4 , and also helps prevent the used disposable needle assemblies  24  from becoming easily available for illegal purposes. 
         [0034]    In a preferred embodiment, a sliding cover  46  is slideably attached on to the top portion  44  of the syringe disposal unit  4 . Preferably, the sliding cover  46  is manually moved between a closing position as shown in  FIG. 3  and an opening position as shown in  FIG. 4 . The sliding cover  46  can preferably have an arrow  462  on the top surface thereof, pointing toward the opening position. The sliding cover  46  can preferably have a protrusion  464 , which can facilitate the sliding movement of the sliding cover  46  when a user tries to move the sliding cover  46  with his/her finger. 
         [0035]    As shown in  FIG. 4 , in order to provide access to the interior space for disposal of the disposable needle assemblies  24 , the top portion  44  of the syringe disposal unit  4  has a through-hole  442 , through which the disposable needle assemblies  24  can pass. When the sliding cover  46  is in the closing position as shown in  FIG. 3 , the through-hole  442  is completely covered by the sliding cover  46  so that disposable needle assemblies  24  are prevented from passing therethrough. When the sliding cover  46  is in the opening position as shown in  FIG. 4 , the through-hole  442  is uncovered so that the used disposable needle assemblies  24  can now pass therethrough into the syringe disposal unit  4 . 
         [0036]    In a preferred embodiment, the through-hole  442  is generally circular as shown. The through-hole  442  is preferably larger than the disposable needle assembly  24  but smaller than the syringe body  22  in diameter, allowing the disposable needle assembly  24  to pass through the through-hole  442  while preventing the syringe body  22  from passing therethrough as can be seen in  FIG. 5 . The through-hole  442  is preferably slightly larger than the disposable needle assembly  24  so that there is only a small clearance between the disposable needle assembly  24  and the inner wall of the through-hole  442 . This can help prevent disposable needle assemblies  24  contained in the syringe disposal unit  4  from being accidentally released even when the sliding cover  46  is in the opening position. 
         [0037]    In a preferred embodiment, a spring (not shown) is operatively attached to the sliding cover  46  so as to bias the sliding cover  46  toward the closing position. This can help prevent the spring cover  46  from being unintentionally opened, and thus further prevent accidental releasing of disposable needle assemblies  24  out of the syringe disposal unit  4 . Additionally or alternatively, the syringe disposal unit  4  has a releasable latch mechanism (not shown) that can hold the sliding cover  46  in the opening position. The latch mechanism is preferably easily releasable such that a slight force can overcome the latch mechanism so as to return the sliding cover  46  back to the closing position. Additionally or alternatively, the syringe disposal unit  4  can also have a releasable latch mechanism (not shown) that can lock the sliding cover  46  in the closing position. 
         [0038]    In a preferred embodiment of the present invention, the syringe disposal unit  4  has a push button  48  installed on to the lateral surface of the top portion  44 . When the push button  48  is pressed, a needle base latch  482  is slidingly moved to an engaging position where the needle base latch  482  protrudes out of the inner wall of the through-hole  442  toward the center thereof as shown in  FIG. 6 . When the disposable needle assembly  24  is positioned in the through-hole  442 , in the engaging position a distal end surface  484  of the needle base latch  482  can contact the outer circumferential surface of the needle base  244  and frictionally prevent the disposable needle base  244  from rotating. Accordingly, a user can unscrew the disposable needle assembly  24  from the syringe body  22  by rotating the syringe body  22  while pressing the push button  48 . 
         [0039]    As shown in  FIG. 7 , when the push button  48  is released, the needle base latch  482  is slidingly moved back to a disengaging position where the needle base latch  482  is retracted in to the inner wall of the through-hole  442 . Accordingly, in the disengaging position, the distal end surface  484  of the needle base latch  482  cannot contact the needle base  244 . 
         [0040]    Preferably, the needle base  244  of the disposable needle assembly  24  can have grooves or ridges  248  on its outer circumferential surface, as shown in  FIG. 1 . This can facilitate the engagement between the needle base latch  482  and the needle base  244 , and thus help further prevent the disposal needle assembly  24  from rotating in the engaging position. As shown in  FIG. 6 , the needle base latch  482  can also have grooves or ridges  486  in the distal end surface  484 , which can engage with the grooves or ridges  248  of the needle base  244 . In a preferred embodiment, the needle base latch  482  is biased such that when the push button  48  is released, the needle base latch  482  is moved to a disengaging position where the needle base latch  482  is retracted into the inner wall of the through-hole  442  and the distal end surface  484  cannot contact the needle base  244 . 
         [0041]    As shown in  FIG. 7 , in a preferred embodiment, the syringe disposal unit  4  has a needle assembly holder  484  movably installed on to the inner wall of the through-hole  442 . The needle assembly holder  484  can be slidingly moved between a holding position as shown in  FIG. 7  and a releasing position as shown in  FIG. 6 . In the holding position, the needle assembly holder  484  protrudes out of the inner wall of the through-hole  442  such that it prevents the disposable needle assembly  24  from falling into the inner space of the syringe disposal unit  4 .  FIG. 8  shows a detached disposable needle assembly  24  held within the through-hole  442  by the needle assembly holder  484 . In the releasing position, the needle assembly holder  484  is retracted into the inner wall of the through-hole  442  such that it now allows the disposable needle assembly  24  to fall into the inner space through the through-hole  442 . 
         [0042]    In a preferred embodiment, the needle assembly holder  484  is moved to the holding position when the push button  48  is released while the needle assembly holder  484  is moved to the releasing position when the push button  48  is pressed. Preferably, when the push button  48  is half pressed, neither the needle assembly holder  484  nor the needle base latch  482  protrudes out of the inner wall of the through-hole  442  so that the needle assembly  24  can fall down into the interior space without interference. Preferably, the needle assembly holder  484  is biased toward the holding position by a spring (not shown). This can further help prevent the disposable needle assemblies  24  from being inadvertently released through the through-hole  442 . 
         [0043]    In a preferred embodiment, the sidewall portion  42  has a viewing window  422  made of puncture resistant material to permit visual observation of the amount of disposable needle assemblies  24  within the inner space of the syringe disposal unit  4 . 
         [0044]    As various modifications could be made to the exemplary embodiments, as described above with reference to the corresponding illustrations, without departing from the scope of the invention, it is intended that all matter contained in the foregoing description and shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.