Injection device

Abstract

The invention relates to an injection device ( 10 ) having a housing ( 15 ) and an injector fluid container ( 12 ) whicj can move, in relation to this housing, between a distal and proximal end position, and also having a pushrod ( 14 ) to act on a plunger 9 23 ) in this container ( 12 ) for the purpose of expelling fluid from the container. A device connection ( 27 ) is provided between the pushrod ( 14 ) and the container, this drive connection is effective in both the proximal end position of the container ( 12 ), it is only effective when the pushrod ( 14 ) is moved in the distal direction.

1 . An injection device comprising a housing ( 15 ;  132 ,  150 ) and a container ( 12 ;  136 ) for an injection fluid or a retainer ( 134 ,  234 ) for a container of this kind, which is displaceable in relation to this housing between a distal end position (FIGS. 2, 3,  9 ,  21 ) and a proximal end position (FIGS. 1, 4,  5 ,  8 ,  11 ,  19 ,  20 ), further comprising a pushrod ( 14 ;  188 ) movable relative to the housing to expel fluid from such a container ( 12 ;  136 ), and comprising a first connecting device ( 27 ;  112 ,  114 ;  242 ,  244 ,  246 ,  248 ), which is position-dependent and/or direction-dependent, between the pushrod ( 14 ;  188 ) and the container ( 12 ;  136 ).  
     
     
         2 . The injection device according to  claim 1 , wherein the first connecting device ( 27 ;  112 ,  114 ;  242 ,  244 ,  246 ,  248 ) is adapted upon movement of the pushrod ( 14 ;  188 ) in the distal direction, to produce a unidirectional, positive connection between the pushrod ( 14 ;  188 ) and the container ( 12 ;  136 ) or the receptacle ( 134 ,  234 ) for the container and to move the container, or the receptacle therefor, together with the pushrod ( 14 ;  188 ) in the distal direction, and which is furthermore adapted to convert a movement of the pushrod ( 14 ;  188 ) in the proximal direction into a corresponding movement of the container ( 12 ;  136 ) or the receptacle ( 134 ,  234 ) for the container in the proximal direction until the container ( 12 ;  136 ) is prevented from moving in the proximal direction in the housing.  
     
     
         3 . The injection device according to  claim 2 , wherein the unidirectional positive connection is formed so that a stop ( 18 ,  20 ;  70 ,  73 ;  260 ) for the distal movement of the container ( 12 ;  136 ) or a receptacle ( 134 ,  234 ) for the container also constitutes a limit for the distal movement of the pushrod ( 14 ;  188 ).  
     
     
         4 . The injection device according to one or more of  claims 1  to  3 , wherein in the distal end position of the container ( 12 ;  136 ) or the receptacle ( 134 ,  234 ) for the container, the first connecting device ( 27 ;  112 ,  114 ;  242 ,  244 ,  246 ,  248 ) is effective in both the proximal and the distal direction, but in the proximal end position of the container ( 12 ;  136 ) or the receptacle for the container, is only effective when the pushrod ( 14 ;  188 ) is moved in the distal direction.  
     
     
         5 . The injection device according to one or more of  claims 1  to  4 , wherein a drive mechanism ( 35 ;  186 ) is provided for the pushrod ( 14 ;  188 ) and further comprising a second connecting device ( 38 ;  122 ,  124 ;  214 ,  216 ,  218 ,  220 ) provided between the drive mechanism ( 35 ;  186 ) and the pushrod ( 14 ;  188 ), which connecting device acts in a position-dependent and/or direction-dependent manner.  
     
     
         6 . The injection device according to  claim 5 , wherein the second connecting device ( 38 ;  122 ,  124 ;  214 ,  216 ,  218 ,  220 ) is adapted to produce a unidirectional positive connection in the proximal direction between the drive mechanism ( 35 ;  186 ) and the pushrod ( 14 ;  188 ) and to move the latter in the proximal direction, together with the drive mechanism ( 35 ;  186 ), and to convert a movement of the drive mechanism ( 35 ;  186 ) in the distal direction into a corresponding movement of the pushrod ( 14 ;  188 ) in the distal direction until the pushrod ( 14 ;  188 ) is prevented from moving in the distal direction.  
     
     
         7 . The injection device according to  claim 5  or  6 , wherein in a proximal position range (FIG. 1) of the container ( 12 ), the second connecting device ( 38 ) produces a connection between the drive mechanism ( 35 ) and the pushrod ( 14 ) in both the proximal and the distal direction.  
     
     
         8 . The injection device according to one or more of  claims 5  to  7 , wherein in a distal position range (FIGS. 2, 3,  21 ) of the container ( 12 ;  136 ), the second connecting device ( 38 ;  214 ,  216 ,  218 ,  220 ) produces a connection between the drive mechanism ( 34 ;  186 ) and the pushrod ( 14 ;  188 ), which connection is effective in the proximal direction and makes it possible to move the drive mechanism ( 35 ;  186 ) in the distal direction relative to the pushrod ( 14 ;  188 ).  
     
     
         9 . The injection device according to one or more of  claims 5  to  8 , wherein the drive mechanism ( 35 ;  186 ) is associated with a detent mechanism ( 46 ;  94 ;  224 ) and a spring ( 11 ;  262 ), in particular a spring made of a plastic material, which acts upon the drive mechanism in the proximal direction and can be compressed by moving the detent mechanism ( 46 ;  94 ;  224 ) in the distal direction, wherein the detent mechanism engages when a predetermined cocked position (FIGS. 3, 9,  21 ) is reached.  
     
     
         10 . The injection device according to  claim 9 , wherein a clip ( 98 ;  176 ) provided on the outside of the housing ( 15 ,  150 ) is formed to release the detent mechanism ( 94 ;  224 ) and to thus trigger an injection process.  
     
     
         11 . The injection device according to one or more of  claims 5  to  10 , wherein the drive mechanism ( 35 ;  186 ) is associated with an actuating member ( 80 ;  206 ) which is preferably disposed in the distal range of the device and makes it possible to slide the move mechanism ( 35 ;  186 ) into its cocked position (FIGS. 9, 21).  
     
     
         12 . The injection device according to one or more of  claims 5  to  11 , wherein the unidirectional positive connection between the pushrod ( 14 ;  188 ) and the container ( 12 ;  136 ) and/or between the drive mechanism ( 35 ;  186 ) and the pushrod ( 14 ;  188 ) is formed in the form of a drive coupling that is unilaterally effective, in particular in the form of a ratchet coupling.  
     
     
         13 . The injection device according to  claim 12 , wherein in the direction counter to the unidirectional positive connection, the connecting device is formed as a frictional, non-positive connection device and/or as a positive connection device that is controlled in a position-dependent manner.  
     
     
         14 . The injection device according to one or more of the preceding claims, wherein the first connecting device comprises a member ( 27 ;  112 ;  242 ,  244 ) that is connected to the container ( 12 ;  136 ) and formed to engage with the pushrod ( 14 ;  188 ).  
     
     
         15 . The injection device according to  claim 14 , wherein the member ( 17 ;  112 ;  242 ,  244 ) connected to the container ( 12 ;  136 ) elastically engages with the pushrod ( 14 ;  188 ) at least in the proximal end position of the container ( 12 ;  136 ).  
     
     
         16 . The injection device according to  claim 14  or  15 , wherein the container ( 12 ;  136 ) is associated with a retainer ( 17 ;  54 ;  134 ,  234 ) which is formed so that it can move relative to the housing ( 15 ;  132 ,  150 ), the member ( 27 ;  112 ;  242 ,  244 ) being formed to engage with the pushrod ( 14 ;  188 ) being disposed on this retainer ( 17 ;  54 ;  134 ,  234 ) and being movable together with it.  
     
     
         17 . The injection device according to one or more of the preceding claims, wherein the second connecting device comprises a member ( 38 ;  112 ;  186 ) provided on the drive mechanism ( 35 ;  186 ), which member is formed to engage with the pushrod ( 14 ;  188 ) and which, at least in the distal end position range of the container ( 12 ;  136 ), engages elastically with the pushrod ( 14 ;  188 ).  
     
     
         18 . The injection device according to one or more of  claims 14  to  17 , wherein depending upon the position of the container ( 12 ) or a retainer which holds it, the member ( 27 ;  38 ) formed to engage with the pushrod ( 14 ) is prevented from moving elastically away from the pushrod ( 14 ) by a member or the like fixed to the housing.  
     
     
         19 . The injection device according to one or more of the preceding claims, wherein, at least in areas, the pushrod ( 14 ;  188 ) is formed in the form of a toothed rod (FIGS. 10;  30 ,  31 ).  
     
     
         20 . The injection device according to  claim 19 , wherein the teeth ( 28 ;  218 ,  248 ) of the toothed rod ( 14 ;  188 ) are formed so that they permit the toothed rod to move only in the proximal direction relative to an elastic detent mechanism.  
     
     
         21 . The injection device according to one or more of the preceding claims, wherein the pushrod ( 14 ;  188 ) is associated with a stop ( 91 ) limiting the movement of the pushrod relative to the housing ( 15 ;  132 ), at least in the proximal direction.  
     
     
         22 . The injection device according to one or more of the preceding claims, wherein the container ( 12 ;  136 ) is associated with a retainer ( 17 ;  54 ;  134 ,  234 ) which holds the container ( 12 ;  136 ) and can move axially in the housing ( 15 ;  132 ) between a proximal and a distal end position.  
     
     
         23 . The injection device according to  claim 22 , wherein the length of the retainer ( 54 ;  134 ,  234 ) is adjustable.  
     
     
         24 . The injection device according to  claim 23 , wherein the retainer ( 54 ;  134 ,  234 ) has a proximal section ( 56 ;  134 ) and a distal section ( 66 ;  234 ) that are connected to each other by an adjustable connection ( 64 ;  236 ,  240 ), in particular by a micro-detent mechanism which makes it possible to change and in particular to shorten the overall length of the retainer ( 54 ;  134 ,  234 ), for example by means of an axial force (FIG. 8A: K).  
     
     
         25 . The injection device according to one or more of  claims 22  to  24 , wherein in its proximal end position, the retainer ( 54 ;  134 ,  234 ) rests with its distal end against a proximal end section of the drive member.  
     
     
         26 . The injection device according to one or more of the preceding claims, wherein the effectiveness of the first and/or second connecting device ( 27 ;  38 ;  112 ,  114 ;  122 ,  124 ;  242 ,  244 ,  246 ,  248 ,  214 ,  216 ,  218 ,  220 ) is a function of the respective position of the container ( 12 ;  136 ).  
     
     
         27 . An injection device having a housing ( 15 ;  132 ,  150 ), comprising an injection fluid container ( 12 ;  136 ) disposed in this housing ( 15 ), further comprising a pushrod ( 14 ;  188 ) movable in relation to the housing ( 15 ;  132 ,  150 ) to expel fluid from this container ( 12 ;  136 ), further comprising a retainer ( 54 ;  134 ,  234 ) serving to hold the container ( 12 ;  136 ) and movable in the housing ( 15 ;  132 ) between a proximal and a distal end position, and comprising a device ( 64 ;  236 ,  240 ) for adjusting the length of this retainer ( 54 ;  134 ,  234 ).  
     
     
         28 . The injection device according to  claim 27 , wherein in its distal range, the retainer ( 54 ;  134 ,  234 ) has abutment means ( 68 ,  73 ;  236 ), determining its proximal end position and/or distal end position relative to the housing ( 15 ;  132 ) and wherein the length adjustment of the retainer ( 54 ;  134 ,  234 ) is carried out relative to these abutment means so that when the length of the retainer ( 54 ;  134 ,  234 ) is changed, the position of the container ( 12 ;  136 ) relative to the pushrod ( 14 ;  188 ) is changed.  
     
     
         29 . The injection device according to  claim 27  or  28 , wherein the length changing device has a micro-detent mechanism ( 64 ;  236 ,  240 ) connecting a proximal section ( 56 ;  134 ) and a distal section ( 66 ;  234 ) of the retainer ( 54 ) to each other in an adjustable way.  
     
     
         30 . The injection device according to one or more of the preceding claims, wherein the housing has at least two parts, and a device ( 144 ) is provided for changing the relative position of housing parts ( 132 ,  150 ), in particular by linearly moving them relative to each other.  
     
     
         31 . The injection device according to  claim 30 , wherein a first housing part ( 132 ) is provided for guiding the retainer ( 134 ,  234 ) holding the injection fluid container ( 136 ) and a second housing part ( 150 ) that is movable in relation to the first has detent means ( 180 ) for the locking of a detent mechanism ( 224 ) provided on the drive mechanism ( 186 ).  
     
     
         32 . The injection device according to  claim 31 , wherein a clip ( 176 ) on the outside of the second housing part ( 150 ) is provided for releasing the detent connection between the detent means ( 180 ) and the detent mechanism ( 224 ).  
     
     
         33 . The injection device according to one or more of  claims 30  to  32 , wherein one of the housing parts ( 150 ) movable relative to each other has a thread ( 148 ,  148 ′), and the other housing part ( 132 ) has a threaded sleeve ( 144 ) that is rotatable relative to the other housing part ( 132 ) but not axially movable, and is in engagement with said thread ( 148 ,  148 ′).  
     
     
         34 . The injection device according to one or more of  claims 30  to  33 , wherein guide means ( 152 ,  156 ,  196 ,  198 ) is provided for linear guidance between the housing parts ( 132 ,  150 ) that are movable relative to each other.  
     
     
         35 . The injection device according to one or more of  claims 30  to  34 , wherein one of the housing parts ( 150 ) is guided in the other ( 132 ).  
     
     
         36 . The injection device according to  claim 35 , wherein the outer housing part ( 132 ) is provided with at least one elongated recess ( 158 ), through which a part ( 196 ) of the inner housing part ( 150 ) protrudes radially outward.  
     
     
         37 . The injection device according to  claim 36 , wherein the outwardly protruding part ( 196 ) of the inner housing part ( 150 ) is provided with an external thread ( 148 ,  148 ′) which engages with the internal thread ( 146 ) of a threaded sleeve ( 144 ) that is disposed on the outer housing part ( 132 ) so that it can rotate, but cannot slide axially.  
     
     
         38 . The injection device according to  claim 33  or  37 , wherein the threads ( 146 ,  148 ,  148 ′) are formed as small pitch threads.  
     
     
         39 . The injection device according to one or more of the preceding claims, wherein the first connecting device ( 186 ) comprises two engaging members ( 214 ,  216 ) that are provided with engaging elements ( 214 ′,  216 ′) adapted to engage in corresponding rows of teeth ( 218 ,  220 ) of a toothed rod ( 188 ) that serves as a pushrod.  
     
     
         40 . The injection device according to one or more of the preceding claims, wherein the second connecting device has two engaging members ( 242 ,  244 ) that are provided with engaging elements ( 242 ′,  244 ′) adapted to engage in corresponding rows of teeth ( 246 ,  248 ) on a toothed rod ( 188 ) that serves as a pushrod.  
     
     
         41 . The injection device according to claims  39  and  40 , wherein the toothed rod ( 188 ) serving as a pushrod has a rectangular, and preferably square cross section and on a first pair of opposing sides, is provided with rows of teeth ( 218 ,  220 ) for the first connecting device and on the second pair of opposing sides, is provided with rows of teeth ( 246 ,  248 ) for the second connecting device.  
     
     
         42 . The injection device according to  claim 41 , wherein the engaging members ( 214 ,  216 ) of the first connecting device and the engaging members ( 242 ,  244 ) of the second connecting device engage each other interdigitally.  
     
     
         43 . The injection device in particular according to one or more of  claims 39  to  42 , wherein the rows of teeth ( 218 ,  220 ) on the opposing sides of a toothed rod ( 188 ) serving as a pushrod and/or the engaging elements ( 214 ′,  216 ′) on engaging members which elastically engage these opposing rows of teeth ( 218 ,  220 ) are offset from each other in an axial direction in order to permit either a full engagement of an engaging element of the first of two elastic engaging members with the associated row of teeth of the pushrod, or a full engagement of an engaging element of the second of two elastic engaging members with the associated row of teeth of the pushrod ( 188 ), and thus allow an improved adjustment potential of the injection device.  
     
     
         44 . An injection device having a housing ( 132 ,  150 ) for receiving a container ( 136 ) for a fluid to be injected, and having a toothed rod that is movable by means of an actuating member to expel fluid from such a container ( 136 ) disposed in the housing, which toothed rod ( 188 ), viewed in cross section, is polygonal and on a plurality of sides of this polygon, is respectively provided with a row of teeth ( 218 ,  220 ,  246 ,  248 ), said rows of teeth cooperating with another member, in particular the actuating member, that cooperates with the toothed rod ( 188 ), said another member having a plurality of engaging members ( 214 ,  216 ), each provided with at least one engaging element ( 214 ′,  216 ′) that is complementary to the associated row of teeth and elastically engages therewith, one engaging member out of this plurality of engaging members ( 214 ,  216 ) engaging fully with the associated row of teeth ( 218 ,  220 ) via its at least one complementary engaging element ( 214 ′,  216 ′), and other engaging members out of this plurality of engaging members being not in full engagement with their associated row of teeth.  
     
     
         45 . The injection device according to  claim 44 , wherein the rows of teeth ( 218 ,  220 ) of the toothed rod ( 188 ) which cooperate with said another member are disposed essentially symmetrically to the longitudinal axis of the toothed rod ( 188 ).  
     
     
         46 . The injection device according to  claim 44  or  45 , wherein said another member is formed as a drive mechanism ( 186 ) for moving the container ( 136 ) in the housing ( 132 ,  150 ) of the injection device.  
     
     
         47 . The injection device according to one or more of  claims 44  to  46 , wherein the toothed rod ( 188 ) has a rectangular cross section, in particular a square one, and said another member has two engaging members ( 214 ,  216 ) which cooperate with rows of teeth ( 218 ,  220 ) on opposing sides of this toothed rod.