Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
303 words
An operable single use needleless hypodermic injector comprising: an elongate housing having a proximal end, a distal end, a hollow bore therethrough and a longitudinal axis; a reservoir at said distal end of said housing, said reservoir having a generally cylindrical chamber defining a longitudinal axis for containing an injectable liquid, said chamber being axially aligned with said longitudinal axis of said housing, said reservoir having a first open end adjacent said housing, a resilient stopper mounted slidably within said chamber, said stopper for sealing said chamber and for ejecting the liquid from said chamber, and a distal second end of said reservoir having an orifice in fluid communication with said chamber, said orifice serving to form a stream of the liquid when said stopper is moved distally in said chamber; and an elongate piston mounted for axial movement within said bore having a proximal end and a distal end, said injector having biasing means for axially biasing said piston to said distal end of said housing, said piston having an armed position wherein said piston is positioned proximally in said housing in opposition to said biasing means, said biasing means thereby having potential energy, retention means for retaining said piston in said armed position, release means for releasing said piston from said armed position and allowing said energy of said biasing means to urge a distal axial movement of said piston, said movement of said piston to engage and to cause a distal axial movement of said stopper through said chamber thereby ejecting the liquid through said orifice, so that the stream of the liquid being formed at said orifice will make a hypodermic penetration when said orifice is placed adjacent dermal tissue, and means for preventing said piston from being retained in said armed position after said release means is released.
Claim 2
Dependent Claim
18 words
The injector of claim 1 wherein said biasing means for distally axially biasing said piston is a spring.
Claim 3
Dependent Claim
266 words
The injector of claim 1 further including: an annular inwardly directed shoulder defining an inner dimension transverse to said longitudinal axis located within said housing; said elongate piston having at least two cantilevers extending proximally therefrom, each of said cantilevers including a radially outwardly directed projection for engaging said shoulder and a radially inwardly directed protuberance, said cantilevers defining a recess having an inside dimension transverse said longitudinal axis; an elongate plunger having a proximal end and a distal end being positioned for slidable movement within said recess, said plunger having a large dimension portion transverse said longitudinal axis and a small dimension portion transverse said longitudinal axis located proximally from and adjacent said large dimension portion; said plunger being positioned so that said large dimension portion is contacting said protuberances when said piston is in said armed position, thereby preventing inward flexion of said cantilevers causing said projections on said cantilevers to engage said shoulder and to retain said piston in said armed position; said piston being releaseable from said armed position by application of a distal axial force causing axial movement of said plunger relative to said protuberances so that said small transverse portion is adjacent said protuberances, thereby allowing inward flexion of said cantilevers so that said projections disengage said shoulder thereby releasing said piston to move distally; and said protuberances on said cantilevers being adjacent said small transverse portion of said plunger with said release means being released, thereby containing said plunger in said recess at said large dimension portion and moving said plunger distally with said distal movement of said piston.
Claim 4
Dependent Claim
40 words
The injector of claim 3 wherein said plunger is configured so that said plunger is withdrawn into said housing with said distal movement of said piston so that said piston is substantially prevented from being retained in said armed position.
Claim 5
Dependent Claim
50 words
The injector of claim 4 wherein said proximal end of said plunger projects from said housing when said piston is in said armed position, said proximal serving as a trigger for receiving said external distal axial force for releasing said release means for releasing said piston from said armed position.
Claim 6
Dependent Claim
34 words
The injector of claim 5 having means for preventing unintentional release and having tamper evidence means for providing visual indication that said means for preventing unintentional release has been moved from its original position.
Claim 7
Dependent Claim
48 words
The injector of claim 1 wherein said reservoir is fastened at said distal end of said housing by means of interacting elements including a first element at said distal end of said bore of said housing and a second conjugate element on said open end of said reservoir.
Claim 8
Dependent Claim
13 words
The injector of claim 7 wherein said first and second elements are non-releaseable.
Claim 9
Dependent Claim
16 words
The injector of claim 1 wherein said housing and said piston are formed from a thermoplastic.
Claim 10
Dependent Claim
37 words
The injector of claim 1 wherein said reservoir is formed from a thermoplastic and said orifice in said distal second end of said reservoir is integrally formed in a single step with said formation of said reservoir.