Needle-less injector

Abstract

A needle-less injector comprises a cartridge ( 3 ) prefilled with liquid (( 9 ), which cartridge contains a free sliding piston ( 32 ) and an injection orifice ( 10 ). A ram ( 22 ) is urged by a pre-loaded spring ( 24 ) for striking the said piston to cause the injections. Adjusting means ( 6 ) can be provided to vary the volume injected. A trigger device ( 26, 30 ) initiates injection only when the optimum contact pressure is reached between the discharge orifice ( 1 ) and epidermis of the subject. The initial loading of the power spring ( 24 ) is sufficient to dispense all of the contents of the medicament cartridge in one dose or multiple sequential doses. Disposable and reusable embodiments are described.

1 . A needle-less injector comprising an actuator and a cartridge filled with a liquid to be injected in a subject, the cartridge having a liquid outlet and a free piston inward of the liquid outlet in contact with the liquid, the liquid outlet comprising an opening in the cartridge, a cap initially covering the opening, said cap being removable to allow the said liquid to pass therethrough, said actuator comprising; 
 (a) a housing having a forward portion adapted to be connected with the cartridges;    (b) an impact member mounted within said housing inward of the forward portion so as to be movable from a first position toward the forward portion to strike said free piston when a cartridge is connected and to continue to move said free piston toward said liquid outlet whereby a dose of the liquid is expelled through the liquid outlet in said cartridge; and    (c) an energy store which, when released, moves said impact member towards said liquid outlet.    
     
     
         2 . The injector of  claim 1 , wherein said energy store comprises: 
 (i) a spring which exerts a force on said impact member to normally urge said impact member toward the liquid outlet; and    (ii) a latch within said housing which engages said impact member to prevent movement of the impact member toward the forward portion in response to said force exerted by said spring, and being mounted to be movable out of engagement with said impact member to a firing position, in which said latch permits such movement.    
     
     
         3 . The injector of  claim 2 , wherein the said spring is a compression spring.  
     
     
         4 . The injector of  claim 2 , wherein the spring is a gas spring provided by a chamber within said housing refilled with pressurized gas which constantly exerts a force on said impact member to normally urge said impact member towards said liquid outlet.  
     
     
         5 . The injector of  claim 4 , wherein said pressurized gas is air.  
     
     
         6 . The injector of  claim 2 , further comprising trigger means for operating said latch to thus initiate the injection in response to a predetermined contact force between said liquid outlet of said cartridge and the subject.  
     
     
         7 . The injector of  claim 6 , wherein said actuator has a user-holdable portion and means for mounting the cartridge so that said user-holding portion is movable relative to the cartridge by the liquid outlet of said cartridge being urged into contact with the subject, and said latch comprises a latch member which is movable to said firing position by the relative movement between said user-holdable portion and said cartridge.  
     
     
         8 . The injector of  claim 7 , wherein said latch member is resilient.  
     
     
         9 . The injector of  claim 1 , wherein the energy store is sufficient to expel a single dose of the liquid.  
     
     
         10 . The injector of  claim 1 , wherein the energy store is sufficient to expel a plurality of successive doses of the liquid.  
     
     
         11 . The injector of  claim 1 , wherein the said cartridge includes a separately held plurality of components which are to be mixed with one another prior to injection and a mixing member for mixing said plurality of components with one another, said impact member further comprising a mixing means being movable toward said liquid outlet for striking said mixing member, whereby said plurality of components are mixed with one another.  
     
     
         12 . A needle-less injector, comprising: 
 (a) a refillable cartridge for confining a liquid to be injected in a subject, said cartridge comprising:    (i) a liquid outlet and a free piston inward of the liquid outlet in contact with the liquid, said liquid outlet comprising an opening in said cartridge, a cap initially covering the opening, said cap being removable to allow the liquid to pass therethrough;    (ii) a separately held plurality of components which are to be mixed with one another prior to being injected injection; and    (iii) a mixing member for mixing said plurality of components with one another, wherein said plurality of compartments are separated by at least one partition and said cartridge further has a penetrating member se mounted therein so as to be movable to a mixing position wherein said at least one partition is penetrated; and    (b) an actuator comprising:    (i) a housing adapted to be connected with said cartridge;    (ii) an impact member mounted within said housing inward of said free piston so as to be movable from a first position toward said liquid outlet to strike said free piston and to continue to move said free piston toward said liquid outlet whereby a dose of the liquid is expelled through the liquid outlet in said cartridge, said impact member further comprising a mixing means being movable toward said liquid outlet for striking said mixing member, said mixing means in striking said mixing member being further operable to move said penetrating member to said mixing position whereby said plurality of components are mixed with one another; and    (iii) an energy store which, when released, moves said impact member towards said liquid outlet.    
     
     
         13 . The injector of  claim 12 , wherein the energy store comprises a spring which exerts a force on said impact member when said impact member is in said first position to normally urge said impact member toward said liquid outlet; and a latch within said housing for engaging said impact member toward said liquid outlet in response to said force exerted by said spring, and being movable to a firing position for permitting such movement.  
     
     
         14 . The injector of  claim 1 , wherein the movement of said impact member expels a fixed dose.  
     
     
         15 . The injector of  claim 1 , wherein the distance of travel of said impact member after striking said free piston is variable to determine the dose of the liquid expelled through said liquid outlet in said cartridge.  
     
     
         16 . The injector of  claim 1 , comprising means for retaining said cartridge for engagement with said actuator, said retaining means being constructed to permit removal of said cartridge.  
     
     
         17 . The injector of  claim 1 , comprising means for retaining said cartridge for engagement with said actuator, said retaining means being constructed to permit the fixed mounting of said cartridge.  
     
     
         18 . The injector of  claim 1 , wherein said cartridge has a body comprising glass.  
     
     
         19 . The injector of  claim 18 , wherein said glass is transparent.  
     
     
         20 . The injector of  claim 18 , wherein said free piston of said cartridge comprises a plastics material.  
     
     
         21 . The injector of  claim 20 , wherein said plastic material is a polymer or copolymer comprising a fluorinated hydrocarbon.  
     
     
         22 . The injector of  claim 20 , wherein said plastic material is a polytetrafluoroethylene.  
     
     
         23 . The injector of  claim 20 , wherein said plastic material is selected from the group consisting of tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-ethylene copolymer, polychlorotrifluoroethylene, poly (vinylidene fluoride), tetrafluoroethylene-perfluoro (propel vinyl ether) copolymer, and hexafluoroisobutylene-vinylidene fluoride copolymer.  
     
     
         24 .- 45 . (Canceled)  
     
     
         46 . A needle-less injector, comprising: 
 (a) a refillable cartridge for containing a liquid to be injected in a subject, said cartridge comprising:    (i) a liquid outlet and a free piston inward of the liquid outlet in contact with the liquid;    (ii) a separately held plurality of components which are to be mixed with one another prior to injection; and    (iii) a mixing member for mixing said plurality of components with one another, wherein said plurality of compartments are separated by at least one partition and said cartridge further has a penetrating member so mounted therein as to be movable to a mixing position wherein said at least one partition is penetrated; and    (b) said actuator comprising:    (i) a housing adapted to be connected with the cartridge;    (ii) impact member mounted within said housing inward of said free piston so as to be movable from a first position toward said liquid outlet to strike the free piston and to continue to move the free piston toward the liquid outlet whereby a dose of the liquid is expelled through the liquid outlet in the cartridge, said impact member further comprising a mixing means being movable toward the liquid outlet for striking said mixing member, said mixing means in striking said mixing member being further operable to move said penetrating member to the mixing position whereby the said plurality of components are mixed with one another;    (iii) a spring which exerts a force on said impact member when said impact member is in said first position to normally urge said impact member toward said liquid outlet;    (iv) a latch within said housing for engaging said impact member to prevent movement of said impact member toward said liquid outlet in response to said force exerted by said spring, and being movable to a firing position for permitting such movement; and    (v) means for varying the said dose of liquid.    
     
     
         47 . The injector of  claim 46 , wherein said actuator further comprises means for removably receiving a cartridge.  
     
     
         48 . The injector of  claim 47 , wherein said actuator further comprises means for retaining said cartridge for engagement with said actuator.  
     
     
         49 . The injector of  claim 48 , wherein said retaining means is constructed to permit removal of said cartridge.  
     
     
         50 . The injector of  claim 48 , wherein said retaining means is constructed to permit the fixed mounting of said cartridge.  
     
     
         51 . The injector of  claim 48 , wherein said cartridge has a body comprising glass.  
     
     
         52 . The injector of  claim 51 , wherein said glass is transparent.  
     
     
         53 . The injector of  claim 51 , wherein said free piston of said cartridge comprises a plastics material.  
     
     
         54 . The injector of  claim 53 , wherein said plastic material is a polymer or copolymer comprising a fluorinated hydrocarbon.  
     
     
         55 . The injector of  claim 53 , wherein said plastic material is a polytetrafluoroethylene.  
     
     
         56 . The injector of  claim 53 , wherein said plastic material is selected from the group consisting of tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-ethylene copolymer, polychlorotrifluoroethylene, poly (vinylidene fluoride), tetrafluoroethylene-perfluoro (propyl vinyl ether) copolymer, and hexafluoroisobutylene-vinylidene fluoride copolymer.  
     
     
         57 .- 62 . (Canceled)  
     
     
         63 . A needle-less injector, comprising: 
 (a) a refillable cartridge containing a liquid to be injected in a subject, said cartridge comprising:    (i) a liquid outlet and a free piston inward of said liquid outlet in contact with the liquid;    (ii) a separately held plurality of components which are to be mixed with one another prior to injection; and    (iii) a mixing member for mixing said plurality of components with one another, wherein the plurality of compartments are separated by at least one partition and said cartridge further has a penetrating member so mounted therein as to be movable to a mixing position wherein said at least one partition is penetrated; and    (b) said actuator comprising:    (i) a housing adapted to be connected with said cartridge;    (ii) impact member mounted within said housing inward of said free piston so as to be movable from a first position toward the liquid outlet to strike said free piston and to continue to move said free piston toward the liquid outlet whereby a dose of the liquid is expelled through the liquid outlet in said cartridge, said impact member further comprising a mixing means being movable toward said liquid outlet for striking said mixing member, said mixing means in striking said mixing member being further operable to move said penetrating member to said mixing position whereby said plurality of components are mixed with one another;    (iii) a spring which exerts a force on said impact member when said impact member is in said first position to normally urge said impact member toward said liquid outlet; and    (iv) a latch within said housing for engaging said impact member to prevent movement of said impact member toward said liquid outlet in response to said force exerted by said spring, and being movable to a firing position for permitting such movement    
     
     
         64 . The injector of  claim 63 , wherein the movement of said impact member expels a fixed dose.  
     
     
         65 . The injector of  claim 63 , wherein the distance of travel of said impact member after striking said free piston is variable to determine the dose of the liquid expelled through said liquid outlet in said cartridge.  
     
     
         66 . The injector of  claim 63 , wherein said actuator further comprises means for removably receiving said cartridge.  
     
     
         67 . The injector of  claim 63 , wherein said actuator further comprises means for retaining said cartridge for engagement with said actuator.  
     
     
         68 . The injector of  claim 67 , wherein said retaining means is constructed to permit removal of said cartridge.  
     
     
         69 . The injector of  claim 67 , wherein said retaining means is constructed to permit the fixed mounting of said cartridge.  
     
     
         70 . The injector of  claim 11 , wherein said cartridge has a body comprising glass.  
     
     
         71 . The injector of  claim 14 , wherein said glass is transparent.  
     
     
         72 . The injector of  claim 70 , wherein said free piston of said cartridge comprises a plastics material.  
     
     
         73 . The injector of  claim 72 , wherein said plastic material is polymer or copolymer comprising a fluorinated hydrocarbon.  
     
     
         74 . The injector of  claim 72 , wherein said plastic material is a polytetrafluoroethylene.  
     
     
         75 . The injector of  claim 72 , wherein said plastic material is selected from the group consisting of tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-ethylene copolymer, polychlorotrifluoroethylene, poly(vinylidene fluoride), tetrafluoroethylene-perfluoro (propel vinyl ether) copolymer, and hexafluoroisobutylene-vinylidene fluoride copolymer.