Abstract:
An apparatus ( 110 ) includes an activation mechanism ( 20 ) and a safety latch ( 122 ). The activation mechanism is operative to deploy a needle ( 116 ) to protrude out of a housing ( 112 ), the needle ( 116 ) having a longitudinal axis. The safety latch ( 122 ) is movably mounted on the housing ( 112 ) and formed with a needle opening ( 129 ) to allow the needle ( 116 ) to pass therethrough. The safety latch ( 122 ) has a first position wherein the needle ( 116 ) is aligned to pass through the needle opening ( 129 ) and a second position wherein the safety latch ( 122 ) is moved with respect to the housing ( 112 ) such that the needle ( 116 ) is blocked from movement in a direction parallel to the longitudinal axis thereof by a portion of the safety latch ( 122 ) distanced from the needle opening ( 129 ).

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 14/258,661, filed Apr. 22, 2014 which is a continuation of U.S. patent application Ser. No. 13/521,167, filed Jul. 9, 2012, which is a section 371 of International Application No. PCT/US2011/021604, filed Jan. 19, 2011, which was published in the English language on Jul. 28, 2011 under International Publication No. WO 2011/090955, which is a continuation-in-part of U.S. patent application Ser. No. 12/689,249, filed Jan. 19, 2010, the disclosures of which are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention generally relates to external drug pumps, and particularly to a needle assembly for a drug pump, particularly suitable for elderly, invalid or physically challenged persons. 
         [0003]    External drug pumps are typically used to deliver to patients substances which contain large molecules which cannot be digested when administered orally, such as insulin. Typically, the pump is adhered to the abdomen of the patient and delivers the substance to the patient via a cannula or needle that is inserted into the patient&#39;s skin. 
         [0004]    U.S. patent application Ser. No. 12/345818 filed Dec. 30, 2008, and PCT Patent Application PCT/US09/69552, filed Dec. 27, 2009, to the same inventor, describe a needle assembly for administering a drug from a vial. (The terms “drug” and “substance” are used interchangeably throughout the specification and claims, and encompass any material administered to a subject. The term “cartridge” throughout the specification and claims encompasses any container for a drug, such as but not limited to, a cartridge, vial, syringe, bottle, ampoule and many more, and is not limited to any size or shape.) The needle assembly includes a needle held in a needle holder, and an activation mechanism for activating delivery of the substance through the needle, such as a push button that initiates the delivery of the substance. The activation mechanism includes a safety latch that prevents the needle from pricking a person accidentally and prevents inadvertent administration of the drug. The safety latch initially impedes movement of the needle holder. When the safety latch is placed on the subject, the safety latch moves to a position that permits moving the needle holder to cause the needle to protrude outwards of the housing to pierce the subject to allow administration of the substance to the subject. 
         [0005]    A problem of this prior art needle assembly is that elderly, invalid or physically challenged persons may find it difficult to push the push button to activate delivery of the substance. 
       BRIEF SUMMARY OF THE INVENTION 
       [0006]    In accordance with an aspect of the invention, there is provided an apparatus comprising an activation mechanism and a safety latch. The activation mechanism is operative to deploy a needle to protrude out of a housing, said needle having a longitudinal axis. The safety latch is movably mounted on said housing and formed with a needle opening to allow said needle to pass therethrough. The safety latch has a first position wherein said needle is aligned to pass through said needle opening and a second position wherein said safety latch is moved with respect to said housing such that said needle is blocked from movement in a direction parallel to the longitudinal axis thereof by a portion of said safety latch distanced from said needle opening. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The present invention will be understood and appreciated more fully from the following detailed description taken in conjunction with the drawings in which: 
           [0008]      FIG. 1  is a simplified illustration of apparatus for administering a substance to a subject, from the prior art (U.S. patent application Ser. No. 12/345818 or PCT Patent Application PCT/US09/69552); 
           [0009]      FIG. 2  is a simplified illustration of a safety latch of the prior art apparatus in the down position, this being the nominal (starting) position as long as the apparatus has not yet been placed upon the user&#39;s body, and a needle holder cannot be pushed down; 
           [0010]      FIG. 3  is a simplified illustration of the prior art safety latch in the up position, which is the position when the apparatus has been placed upon the user&#39;s skin; 
           [0011]      FIG. 4  is a simplified illustration of lifting the prior art apparatus off the patient&#39;s body after finishing the drug administration, which causes the safety latch to move back to the down position; 
           [0012]      FIG. 5  is a simplified illustration of the prior art needle holder moving back up and getting stopped in the up position with the needle retracted back into the housing of the apparatus; 
           [0013]      FIG. 6  is a simplified illustration of biasing device release apparatus used in administering a substance to a subject, constructed and operative in accordance with an embodiment of the present invention; 
           [0014]      FIG. 7  is a simplified illustration of a safety latch of the biasing device release apparatus of  FIG. 6  in the up position, which is the position when the apparatus has been placed upon the user&#39;s skin; 
           [0015]      FIG. 8  is a simplified illustration of an actuator moving a biasing device arrestor out of a housing so as not to block a biasing device which can urge a needle of the apparatus to pierce a patient&#39;s skin, in accordance with an embodiment of the present invention; 
           [0016]      FIG. 9  is a simplified illustration of the biasing device urging the needle to a piercing position, in accordance with an embodiment of the present invention; and 
           [0017]      FIG. 10  is a simplified illustration of the biasing device release apparatus lifted off the patient&#39;s body after finishing the drug administration, which causes the safety latch to move back to the down position and the needle to be retracted back into the housing. 
           [0018]      FIGS. 11A and 11B  are simplified perspective illustrations of the biasing device release apparatus employed in another apparatus (drug pump) for administering a substance to a subject, constructed and operative in accordance with an embodiment of the present invention; 
           [0019]      FIG. 12  is a simplified illustration of the inside of the apparatus in the position of  FIGS. 11A-11B   
           [0020]      FIGS. 13A and 13B  are simplified perspective illustrations of the apparatus of  FIGS. 11A-11B , in a second stage, after application of the apparatus on the patient&#39;s body, in accordance with an embodiment of the present invention; 
           [0021]      FIG. 14  is a simplified illustration of the inside of the apparatus in the position of  FIGS. 13A-13B ; 
           [0022]      FIG. 15  is a simplified perspective illustration of the apparatus of  FIGS. 11A-11B , in a third stage, in which the needle protrudes out of the pump and is inserted in the body, in accordance with an embodiment of the present invention; 
           [0023]      FIG. 16  is a simplified illustration of the inside of the apparatus in the position of  FIG. 15 ; 
           [0024]      FIGS. 17  A and  17 B are simplified perspective illustrations of the apparatus of  FIGS. 11A-11B , in a fourth and final stage, after removing the apparatus from the patient&#39;s body, in which a protector blocks the needle after use, in accordance with an embodiment of the present invention; and 
           [0025]      FIG. 18  is a simplified illustration of the inside of the apparatus in the position of  FIGS. 17A-17B . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0026]    Reference is now made to  FIG. 1 , which illustrates apparatus  10  for administering a substance, for example, insulin, to a subject, from the prior art (U.S. patent application Ser. No. 12/345818 or PCT Patent Application PCTIUS09/69552. 
         [0027]    A cartridge  12  (also referred to as a vial, the terms being used interchangeably) is mounted on a housing base  14 . For some applications, a cartridge piercing mechanism  18  is movably (e.g., rotatably) coupled to housing base  14  and pierces the distal end of cartridge  12 . The substance to be administered flows from cartridge  12  to an activation mechanism  20  via a tube (not shown). The activation mechanism  20  has a control button  22  and is typically coupled to the housing base  14 . The activation mechanism  20  is configured to inse11 a cannula and/or a needle through the subject&#39;s skin and to deliver the substance via the cannula and/or the needle. The embodiments of the invention are described with reference to a needle alone, but apply as well to a needle disposed in a cannula or any other delivery device. The tem1 “needle” is used throughout the specification and claims to encompass all such delivery devices. 
         [0028]    Apparatus  10  typically includes a motor, a battery and a control unit (all not shown). After the needle has penetrated the skin of the patient, the control unit controls operation of the motor to administer a controlled amount of the substance to the patient at a controlled rate of delivery. Of course, the needle assembly of the present invention can be used in other applications and does not have to be used with a controlled motorized delivery system. 
         [0029]    Reference is now made to  FIGS. 2 and 3 , which illustrate a safety latch of the prior art. Control button  22  has a shaft  24  which is arranged to move (vertically downwards in the sense of the drawings) against a needle holder  26  ( FIG. 3 ) which holds a needle  28 . The shaft  24  and the needle holder  26  are both confined to move in a (e.g., tubular) housing  30 , but there is a difference in their movements. Shaft  24  is confined to translate downwards in housing  30  with no rotation. In contrast, needle holder  26  can not only translate but can also rotate in housing  30 , as will be explained more in detail below. 
         [0030]    The movement of needle holder  26  is selectively impeded by a safety latch  32 , which is pivotally mounted on housing base  14  about a pivot  34 . Safety latch  32  is arranged to selectively pivot in and out of a complimentary shaped groove  37  ( FIG. 1 ) formed in housing base  14 . Safety latch  32  includes a first arrestor  36  at a distal end thereof and a second arrestor  38  proximal to and spaced from the first arrestor  36 . The arrestors may be shaped as lugs or other projections or any other structure suitable for arresting motion of needle holder  26  as will be explained below. 
         [0031]      FIG. 2  shows safety latch  32  in the down position, which is its nominal (starting) position as long as apparatus  10  has not yet been placed upon the user&#39;s body. In this position, first arrestor  36  abuts against an ear  40  that projects from a bottom portion of needle holder  26 . It is noted that pushing ear  40  down against a surface  42  of first arrestor  36  will not cause downward movement of needle holder  26  because this will simply pivot first arrestor  36  about the pivot  34  causing another surface  44  of first arrestor  36  to abut against the bottom surface of housing  30 . Thus, when safety latch  32  is in the down position, needle holder cannot be pushed down (in the sense of the drawing of course). 
         [0032]      FIG. 3  shows safety latch  32  in the up position (that is, it has pivoted upwards about pivot  34 ), which is the position when apparatus  10  has been placed upon the user&#39;s skin. First arrestor  36  has been moved out of the way of ear  40  of needle holder  26 , so that control button  22  can now be pressed down to move needle holder  26  downward, thereby piercing the patient&#39;s skin. Needle  28  remains inserted in the patient for the duration of the drug administration. Pressing control button  22  down causes shaft  24  to become locked in the down position in housing  30 , such as by means of one or more splines (not shown here), which radially project outwards from shaft  24 , sliding past one or more chamfered resilient tongues (not shown here) mounted in housing  30 . After the splines slide past tongues, the splines become locked in place by the action of the tongues resiliently snapping back in place over them. 
         [0033]    After finishing the drug administration, apparatus  10  is lifted off the patient&#39;s body. This causes safety latch  32  to move back to the down position as shown in  FIG. 4 , thereby moving second arrestor  38  away from ear  40 . A biasing device  47 , such as a leaf spring biased between first arrestor  36  and housing base  14 , may be employed to impart a returning force on safety latch  32  to move it back to the down position. A slanted tongue  50  applies a downward force on ramp  52 , thereby permitting needle holder  26  to rotate counterclockwise until slanted tongue  50  slides off ramp  52 . At this point, needle holder  26  jumps back up and ear  40  gets caught on a shoulder  54  formed on housing  30  as shown in  FIG. 5 . In this position, needle bolder  26  cannot move back down because of ear  40  being arrested against shoulder  54 . Accordingly, needle  28  is trapped back inside apparatus  10  in a safe position, and apparatus  10  may be safely discarded. 
         [0034]    Reference is now made to  FIG. 6 , which illustrates biasing device release apparatus  60  for administering a substance to a subject, constructed and operative in accordance with an embodiment of the present invention. Elements of the present invention which are identical or equivalent to elements described above for the prior art are designated with the same reference numerals. 
         [0035]    As previously described, in the prior art apparatus, after drug administration, needle bolder  26  retracts back into housing  30  by the action of counterclockwise rotation and ear  40  getting caught on shoulder  54  formed on housing  30 . In the present invention, this same arrangement can be used. Alternatively or additionally, a biasing device  59 , such as a coil spring, can be used to retract needle holder  26  back into housing  30  after drug administration. Biasing device  59  is arranged to apply an urging force on needle  28  in the direction of arrow  57  (upwards in the sense of the drawings). 
         [0036]    With biasing device release apparatus  60 , the user does not have to apply a force for the mechanical operation of the device. Rather either there is no control button to push down, or alternatively the control button can be touch sensitive or be operated on slight pressure, and a biasing device  70 , such as a coil spring, is released to push down needle  28 , as described below. Biasing device  70  is stronger than biasing device  59 . Biasing device  70  is arranged to apply an urging force on needle  28  in the direction of arrow  71  (downwards in the sense of the drawings). 
         [0037]    Apparatus  60  includes a biasing device arrestor  62 , such as a tongue or dog mounted on a shaft  63 , and enters housing  30  through an aperture  64 . An actuator  66  is provided for moving biasing device arrestor  62 . For example, actuator  66  may be, without limitation, a step motor, linear actuator, solenoid and the like. In the non-limiting illustrated embodiment, actuator  66  is a step motor that rotates a drive gear  68  that meshes with a spur gear  72  mounted on shaft  63 . Biasing device arrestor  62  may be threadedly mounted on a threaded portion  74  of shaft  63 . 
         [0038]    A safety latch position sensor  76  is provided for sensing when safety latch  32  moves to the up position of  FIG. 7 . Safety latch position sensor  76  may be, without limitation, a reed switch or any other kind of switch or sensor suitable for sensing the movement of safety latch  32  to the up position. Safety latch position sensor  76  is in communication with a controller  78 , which controls operation of actuator  66 . As mentioned above, the prior art apparatus  10  typically includes a motor, a battery and a control unit. Actuator  66  can be this same motor and controller  78  may be this same control unit, or they may be separate units. 
         [0039]      FIG. 6  shows safety latch  32  in the down position, which is its nominal (starting) position as long as the drug administering apparatus has not yet been placed upon the  25  user&#39;s body, corresponding to  FIG. 2  of the prior art. As described above, in this position, needle holder  26  cannot be pushed down (in the sense of the drawing). In the present invention, in this position, biasing device arrestor  62  is inside housing  30  and blocks biasing device  70 , preventing it from pushing down on needle  28 . 
         [0040]      FIG. 7  shows safety latch  32  in the up position (corresponding to  FIG. 3  of the prior art), which is the position when the drug administering apparatus has been placed upon the user&#39;s skin. Safety latch position sensor  76  senses the movement of safety latch  32  to the up position and signals controller  78  that safety latch  32  is now in the up position. Controller  78  thereupon commences operation of actuator  66 . In a preferred embodiment, controller  78  initiates operation of actuator  66  after a predetemlined time delay (e.g., 5-15 seconds) to ensure that the drug administration apparatus was indeed placed on purpose on the patient for administering the drug. 
         [0041]    When operated, actuator  66  moves biasing device arrestor  62  out of aperture  64 , as shown in  FIG. 8 . In the non-limiting illustrated embodiment, actuator  66  rotates drive gear  68 , which in turn rotates spur gear  72  to rotate shaft  63 . Rotation of shaft  63  causes biasing device arrestor  62  to move linearly out of aperture  64  along threaded portion  74 . When biasing device arrestor  62  reaches the end of threaded portion  74 , it rotates freely on shaft  63  and moves no further. 
         [0042]    As soon as biasing device arrestor  62  has moved out of aperture  64 , biasing device  70  is no longer blocked and it now pushes down on needle  28  (overcoming the weaker biasing device  59 ), as shown in  FIG. 9 . Needle  28  now piercing the patient&#39;s skin and administers the drug. As described for the prior art apparatus, shaft  24  becomes locked in the down position in housing  30 . 
         [0043]    After finishing the drug administration, the apparatus is lifted off the patient&#39;s body. As described for the prior art apparatus, this causes safety latch  32  to move back to the down position as shown in  FIG. 10 , and needle  28  is trapped back inside the apparatus in a safe position, and the apparatus may be safely discarded. 
         [0044]    Reference is made to  FIGS. 11A-11B  and  12 , which illustrate the biasing device release apparatus  60  employed in another apparatus  110  (also referred to as drug pump  110 ) for administering a substance to a subject, constructed and operative in accordance with an embodiment of the present invention. Elements of biasing device release apparatus  60  are designated with the same reference numerals as above. 
         [0045]    The activation mechanism  20  is also employed in this embodiment. However, as opposed to the previously described embodiments, in apparatus  110 , the needle is not retracted back into the housing after drug administration, but there is a protector that blocks the needle after use for preventing accidental needle pricks, as is described more in detail hereinbelow. 
         [0046]    In apparatus  110 , the cartridge (not shown) is mounted on a housing base  112  (or simply housing  112 ), as shown in  FIGS. 11A-11B . A hollow needle (not shown) is provided in housing  112  for piercing a septum at a distal end of the cartridge. The substance to be administered flows from the cartridge eventually to a needle  116  held in a needle holder  118  (confined to move in a housing  117 ), as controlled by biasing device release apparatus  60 . As described above, with biasing device release apparatus  60 , there is no control button to push down. Instead biasing device  70  is released to push clown needle  116 , in the same manner as described above. 
         [0047]    The movement of needle holder  118  is selectively impeded by a safety latch  122 , which is pivotally mounted on housing base  112  about a pivot  124 . Safety latch  122  is arranged to selectively pivot in and out of a complimentary shaped groove  126  formed in housing base  112 . Safety latch  122  may be biased by a biasing device  128 , such as a coil spring. Safety latch  122  is formed with a needle opening  129  to allow needle  116  to pass therethrough. 
         [0048]    In the first stage shown in  FIGS. 11A ,  11 B and  12 , before operation, safety latch  122  blocks the path of needle  116  for preventing against inadvertent, premature activation (the blocking mechanism as described, for example, in U.S. patent application 12/345818 or PCT Patent Application PCT/US09/69552). 
         [0049]    A microsensor  120 , such as a photo-microsensor, may be provided for sensing the position of the needle for use in conjunction with the control unit to control the various stages of the operation of the pump. In addition to the photo-microsensor  120 , another sensor  130  ( FIG. 12 ) may be provided for sensing the position and operation of safety latch  122 . For example, sensor  130  may be a magnet sensor  130  that senses if a magnet  132  mounted on the distal end of safety latch  122  is near sensor  130  or not. 
         [0050]    In the second stage shown in  FIGS. 13A ,  13 B and  14 , apparatus  110  is placed on the patient&#39;s body (not shown), and safety latch  122  has pivoted to be flush with housing base  112 . Needle  116  is now aligned to be advanced through needle opening  129  of safety latch  122 . An indication may be provided that pump  110  is on the body by magnet sensor  130  sensing the magnet  132  on safety latch  122  (or any other suitable sensing mechanism). (It is noted that biasing device release apparatus  60  is not shown in  FIG. 14  for the sake of simplicity.) 
         [0051]    As described above, biasing device  70  of biasing device release apparatus  60  is then released to push down needle  116  into the patient&#39;s body, in the same manner as described above. Needle  116  advances through needle opening  129  of safety latch  122  to the position shown in  FIGS. 15 and 16  (third stage of operation). The sensing mechanism may provide an indication indicating that the needle  116  is inserted. Needle  116  stays locked in the insertion position. 
         [0052]    Reference is made to  FIGS. 17A ,  17 B and  18 . In the fourth and final stage of operation, after administrating the substance, pump  110  is removed from the patient&#39;s body, thereby releasing safety latch  122  to pivot to the down position. However, since needle  116  is already protruding out of the housing and remains locked in the protruded position, needle  116  does not align with needle opening  129  of safety latch  122 , as seen best in  FIG. 18 . Thus, safety latch  122  serves as a protector that blocks the tip of needle  116  after use of pump  110  for preventing accidental needle pricks. 
         [0053]    It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations and subcombinations of the features described hereinabove as well as modifications and variations thereof which would occur to a person of skill in the art upon reading the foregoing description and which are not in the prior art.