Abstract:
A portable medicament dispensing device having a mechanism which is not susceptible to jamming for dispensing the medication to a user. The device employs a coupling for coupling the relative motion between reciprocating body members housing the ancillary components and a barrel plunger associated with the syringe. One embodiment provides a pivoting coupling whereas an alternate uses a rack and pinion system. The advantage of simplifying such mechanisms results in a structure which has smooth unencumbered motion with fewer parts to avoid mechanical jamming during use.

Description:
[0001]    This application claims priority from U.S. patent application Ser. No. 61/176,128 filed May 7, 2009, the contents of which are incorporated herein. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to a medicament dispenser and more particularly, the present invention relates to a structure for dispensing a medicament where the structure has a mechanical coupling member to substantially reduce jamming of the components normally attributable to such devices. 
       BACKGROUND OF THE INVENTION 
       [0003]    Single use single dose medicament delivery devices are widely known and are generally used to dispense medicaments such as epinephrine in an urgent manner to a user. The so called “epi pen” is a typical example of such arrangements. One of the significant disadvantages inherent with these devices relates to jamming. The existing devices often employ spring configurations for movement of key parts such as the needle as well as the barrel which assists in delivery of the medicament to the needle. In the scenario where a jam has occurred, the result can be fatal if the user cannot repair the device to function properly. In some instances, repair is impossible given urgent time constraints and the user is forced to dismantle or destroy the structure in order to gain access to the medication. 
         [0004]    The above is possible where the user is not a child or a user otherwise not capable of achieving access. To address the limitations in the art, a variety of solutions have been advanced in the art. An example is provided in U.S. Pat. No. 6,808,507, issued Oct. 26, 2004, to Roser. In the arrangement discussed in this patent, a telescopic member is provided and a spring surrounds the needle. The arrangement is useful, however there is still a possibility that the spring could be defective or otherwise fail, thus complicating delivery. 
         [0005]    Botich et al., in U.S. Pat. No. 6,039,713, issued Mar. 21, 2000, teach a pre-filled retractable needle device. The device, as is common with most arrangements, includes reciprocating body members, springs, etc. In this instance the device has a number of movable parts which elevates the possibility for jamming or failure. 
         [0006]    U.S. Pat. No. 6,846,301, issued to Smith et al., Jun. 25, 2005, teach a disposable safety syringe with a vacuum system to withdraw the needle into the body after use. There is no provision for a mechanical linkage for quick delivery of the medicament. 
         [0007]    Given the extent of development in the prior art, there exists a need for an improved medicament dispenser which is efficient and reliable while maintaining a lower profile than those devices currently available. 
         [0008]    The present invention provides a significantly improved arrangement which is devoid of the structural limitations inherent with the prior art. 
       INDUSTRIAL APPLICABILITY 
       [0009]    The technology set forth herein has utility in the medical arts inter alia. 
       DESCRIPTION OF THE INVENTION 
       [0010]    One object of one embodiment of the present invention is to provide an improved medicament dispensing device. 
         [0011]    An important objective of this invention is to provide an automatic injection device for dispensing a medicament, the device having a needle connected to a barrel adapted to retain medicament and a plunger within the barrel, characterized in that the device comprises: 
         [0012]    a first body member and a second body member coaxially mounted for reciprocal movement, and housing the needle, the barrel and the plunger; 
         [0013]    drive means connected between the first body member and the second body member for effecting the reciprocal movement; and 
         [0014]    coupling means on each of the first body member and the second body member coupled with the drive means, whereby upon reciprocal movement of the first body member and the second body member, the needle is exposed and the plunger is moved within the barrel for discharging the medicament. 
         [0015]    In accordance with another object of one embodiment of the present invention, there is provided a method for dispensing a medicament from a device having a needle, connected to a barrel adapted to retain medicament and a plunger within the barrel, the device having a first body member and a second body member mounted thereon for reciprocal movement comprising the steps of: 
         [0016]    providing a cover means for covering a tip of the needle; 
         [0017]    positioning the device in contact adjacent a user&#39;s skin; 
         [0018]    urging the device against the user to expose, in a first stage, the needle through the cover means; and 
         [0019]    urging, in a second stage, the device against the user to reciprocally move the cover means and the plunger where the needle penetrates a user&#39;s skin and the medicament is forced through the barrel and the needle to deliver the medicament to the user. 
         [0020]    Having thus generally described the invention, reference will now be made to the accompanying drawings, illustrating preferred embodiments. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]      FIG. 1  is an exploded view of the arrangement according to one embodiment of the present invention; 
           [0022]      FIG. 2  is a cross-section of  FIG. 1  with the arrangement shown in the ready to use state; 
           [0023]      FIGS. 3 through 6  are cross-sections of the device sequentially illustrating the components positions as the device is advanced through a pre-use position through to use and withdrawal; 
           [0024]      FIG. 7  is a cross-section of an alternate embodiment; 
           [0025]      FIG. 8  is a perspective view of yet another embodiment; 
           [0026]      FIG. 9  is a perspective view of a further alternate embodiment of the present invention; 
           [0027]      FIG. 10  is an exploded view of the device shown in  FIG. 9 ; 
           [0028]      FIG. 11  is a longitudinal cross-section of the device before use; 
           [0029]      FIG. 12  is a longitudinal cross-section of the device in a use position; and 
           [0030]      FIG. 13  is a longitudinal cross-section of the device in a post use position. 
       
    
    
       [0031]    Similar numerals used in the drawings denote similar elements. 
       BEST MODE FOR CARRYING OUT THE INVENTION 
       [0032]    Referring now to the drawings,  FIG. 1  illustrates one embodiment of the present invention. The overall arrangement is denoted by numeral  10 . The arrangement provides an exterior body, shown in the example in two sections  12  and  14 . Section  12  provides an opening  16  to allow a user visibility of the interior to determine that the device has been discharged. This will be discussed in greater detail herein after. 
         [0033]    Turning to the major components of the device, a second body member  18  is configured for reception and slidable movement with the exterior body supra. Member  18  has a mounting  20  with, as shown in the example, projections  22  configured for fixed location in seating  24  in body members  12  and  14 . A drive member  26  is rotatably connected to mounting  20  and at one end thereof has a pivotally connected use indicator member  28  at pivot point  30  for indicating when the unit is used. The opposed end of member  26  pivotally connects coupling member  32  at pivot point  34 . Member  32 , at the opposed end thereof, has a pivotal connection  36 . The connection at  36  is with a barrel plunger  38  received within barrel  40 . Barrel  40  terminates in needle hilt  42  which, in turn, receives needle  44 . As is illustrated, the barrel  40  retains a predetermined amount of medicament forwardly of plunger  38 . 
         [0034]    In order to provide protection and sterility to the device  10 , the same includes a cover  46 . The same is configured to always extend outwardly sufficiently to completely cover the tip of the needle. In this manner, springs  48  or other resilient means urge cover member  50  outwardly of a terminal end  52  of body  18 . The cover member  50  also provides a foam cap  54  or other resilient material which protects the tip of the needle  44 . This also assists in preventing spillage from the tip. As a further precaution and for adding durability and aesthetic appeal, a secondary cap  56  is frictionally retained by body members  12  and  14  at perimeter lip  58 . 
         [0035]    In order to bias the needle  44  in the position shown in  FIG. 2 , the storage or standby position, springs  59  are provided extending between mount  20  and spring retainers  62 .  FIG. 1  illustrates the springs in a compressed state. 
         [0036]    With reference to  FIGS. 3 through 6 , shown are the various dispositions of the elements from a pre-injection position ( FIG. 3 ) to a post injection position ( FIG. 6 ). 
         [0037]      FIG. 3  depicts the position of the elements in a relaxed, pre-injection state where the cover  50  is spaced from the user, U. In  FIG. 4 , first stage contact is made with the user, U. The cover  50  is forced backwardly toward terminal end  52 , the springs  48  are compressed and the needle tip penetrates the foam cap  54  through to the skin of the user, U. In order to administer the medicament, the body formed by members  12  and  14  is urged forward to the position shown in  FIG. 5 . This movement results in the pivotal movement of coupling  32  by the motion of drive member  26 . The coupling member  32  movement, in turn, by the pivotal connection, urges plunger  38  forward to discharge the medicament contained within barrel  40 . 
         [0038]    As will be realized from a review of  FIGS. 4 and 5 , once injection has been completed, indicator  28  extends rearwardly within the body to be visible within opening  16 . This is indicative that the unit is used. 
         [0039]      FIG. 6  illustrates the disposition of the components subsequent to an injection. 
         [0040]    Turning now to  FIG. 7 , shown is a longitudinal cross-section of an alternate embodiment of the device. In this embodiment, the drive member is a toothed pinion  61 , rotatably mounted to mount  20 . Cooperating with pinion  61  is a pair of opposed toothed racks  63  and  64 . Pinion  61  is received by racks  63  and  64  in the same manner as a rack and pinion system used in an abundance of mechanical systems. In the embodiment shown, rack  63  is integral with body member  18 , while rack  64  is integral with plunger  38 . Relative movement between the first body member and the second is the same as that discussed supra with respect to the first embodiment. As is evinced in the Figure, rack  63  is disposed in advance of rack  64 . This staggered relationship allows for free movement of the outer body (members  12  and  14 ) to advance plunger  38 . 
         [0041]      FIG. 8  illustrates an embodiment of the device where an aperture  66  within the body is adapted to receive an elongate length  68 , such as a lanyard, a hook  70 , a clasp  72 , a ring  74 , etc. to allow for easier portability. 
         [0042]    Referring now to  FIG. 9 , shown is a further embodiment of the present invention in an assembled state. The embodiment shown is generally similar to the embodiment that has been previously discussed, with this arrangement further including a top grip member  75  which, in the example, comprises a rubber material with a plurality of raised sections  76 , which raised sections  76  are in spaced relation to provide, for example, a thumb rest for actuating the device. The material of which the top grip  75  may be made can include any material suitable for this purpose and may simply comprise the material of which the body members  12  and  14  are composed. In order to complement the use of the article, body  14  includes concavities  78 , which concavities are useful to assist a user (not shown) in holding the device  10 . 
         [0043]    Turning to  FIG. 10 , shown is an exploded view of the device shown generally in  FIG. 9 . Reference will be made to  FIGS. 10 through 13  for the following description. In this embodiment, each of the body members  12  and  14  includes a threaded section  80  and  82 , respectively. This is for purposes of engaging cap  56  which, in this embodiment is threaded (not shown) for purposes of engaging the threads  80  and  82 . The cap  56  is of the variety that it is removable for a single use only. Such caps are known in the art. As a further security feature, the cap may include a breakaway seal  84  which typically takes the form of a ring attached to the body of the cap  56  by disengageable or breakaway connectors as is well known in the art. 
         [0044]    As has been indicated previously, body members  12  and  14  are referred to collectively as a first body member, whereas the second body member  18 , in this embodiment, includes a needle cover  88 , which needle cover  88  substantially surrounds the entire needle and tip. At the terminal end of the needle  44  there is provided the foam cap  54  which accommodates the tip of the needle  44  which also cooperates with a cover member  88  to effectively surround and close the needle  44 . This is obviously contributory to the hygiene and sterility of the device. Disposed coaxially about needle  44  and within the internal volume of cover there is disposed a spring  90  which is positioned between the needle cover  88  of member  86  and seating  92  within second body member  18  as shown. This retains the spring  90  until the device  10  is tended for use. 
         [0045]    As is evident from  FIGS. 10 through 13 , the first body member formed by sub members  12  and  14  and the second body member  18  house the major components of the device and specifically, the plunger  38 , barrel  40 , needle hilt  42  and needle  44 . As with the previous embodiments, second body member  18  includes the toothed rack coupling means  63 , whereas the plunger  38  and more particularly, the arm of the plunger includes the second toothed rack coupling means  64 . As with the previous embodiments, pinion  61  acts as a drive member which connects both of the racks  63  and  64 . In this embodiment, observation window  94  is provided in the structure and visible through connected body members  12  and  14  to allow the user to determine whether barrel  40  contains any medicament and whether the medicament has been compromised. 
         [0046]    This has been noted with respect to the previously described embodiments, in the embodiment shown in  FIGS. 9 through 13 , body members  12 ,  14  and second body member  18  are coaxially mounted and designed for reciprocal movement. As a particularly and beneficial advantage, in the embodiment shown in  FIGS. 9 through 13  second body member  18 , in opposition to the front cap  88  includes a terminal wall  100 . As best seen in  FIG. 11 , terminal wall  100  is spaced from wall  102 , which is formed by the connection of body members  12  and  14 . This space permits movement of the body member  18  relative to assembled members  12  and  14  sufficiently to allow the needle  44  to penetrate cover  88  before injection. This avoids spillage and allows accurate injection of the medicament without wastage and allows for intramuscular injections. 
         [0047]    As a further attendant advantage, the embodiment under discussion also provides for a locking mechanism  104 , shown in the example as a leaf spring and best shown in  FIGS. 10 and 13 . Spring  104 , when the device is in a ready to use position is compressed by disposition of body members  12 ,  14  and  18  as illustrated in  FIG. 11 . 
         [0048]    Turning to  FIG. 12 , the device  10  is shown in an injection position where the needle  44  has penetrated the foam cap  54  and end cap  88  and where second body member  18  is retracted within the first body member composed of members  12  and  14 . As is evident, the spring  90  is compressed, with the plunger  38  moved forwardly within the barrel  40  and with the rack  64  moved forwardly relative to the position shown in  FIG. 11 . In a similar manner, rack  63  is moved rearwardly as shown in  FIG. 12 . The locking member  104  is now compressed inside the gear rack  63  as shown in  FIG. 12 . 
         [0049]    Turning now to  FIG. 13 , shown is a longitudinal cross-section of the device  10  subsequent to injection of the medicament. As is obvious from the illustration, once body member  18  is returned to the extended position with spring  90  relaxed, lock member  104  has nothing further to maintain a compressed state and therefore springs upwardly in a diagonal pattern as shown in  FIG. 13 , with the terminal end of  106  of spring  104  engaging the under surface of body member  14 . This arrangement effectively locks retractable movement of body member  18  into the first body member  12 ,  14  whereby the device  10  cannot be reused. This is simply prevented by the lock arrangement  104 . Further, as illustrated in  FIG. 13 , the second body member  18  fully extends to provide the cap  54  and end cap  88  to completely encapsulate and extend over the tip of needle  44  so that there is no possibility of inadvertent contact of the used needle with a user. As further benefit, as noted above with respect to the previous embodiments the opening  16  in body member  12  allows the user to determine whether the device has been discharged. A similar structure to that noted herein previously is provided for this benefit. 
         [0050]    Other features of the device include: 
         [0051]    the drive means may comprise an indirect drive; 
         [0052]    the drive member is rotatably mounted to a support fixedly secured within the second body member; 
         [0053]    the coupling means is connected to the drive member for pivotal motion relative thereto; 
         [0054]    the coupling means is connected to the barrel for pivotal motion relative thereto; rotatable drive member includes stop means for limiting the movement between the first body member and the second body member; 
         [0055]    device is a single use and single dose device; 
         [0056]    the device includes indicator means for indicating when the device is discharged of the medicament; 
         [0057]    the barrel and the first body member are mounted for coaxial movement in the same direction; 
         [0058]    coupling means for coupling the rotatable drive member with the plunger, and the second body member; 
         [0059]    a one time removable cap on the cover; 
         [0060]    a break away security seal on the cap; 
         [0061]    cover means for covering a tip portion of the needle; 
         [0062]    a cap for releasable positioning over the cover means; 
         [0063]    a retraction means for retracting the needle into the second body member subsequent to use; 
         [0064]    springs mounted on the first body member as the retraction means; 
         [0065]    springs for the cover means for urging the cover means back after use to cover the tip portion of the needle; 
         [0066]    a section to allow for visibility of the indicator means; and 
         [0067]    the first body member includes an aperture for receiving a member selected from the group consisting of an elongate length, a hook, a clasp and a ring.