Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
227 words
A hypodermic syringe comprising a housing having a needle chamber and a receiving chamber, a hollow needle mounted for slidable displacement in said needle chamber in a retracted position, said receiving chamber being sealed and containing an injection liquid therein, first piston means acting on said hollow needle for displacing said needle to an extended position in which the needle projects from said housing for piercing the skin of a subject against which the housing is placed, second piston means in said receiving chamber for acting on said injection liquid to pressurize the same, holder means holding said first and second piston means in respective retracted position, passage means connecting said first and second chambers, closure means normally closing said passage means, and actuator means for releasing said holder means to permit said first and second piston means to move to respective extended positions in which the hollow needle is displaced to its extended position and the injection liquid is pressurized, said closure means being positioned in the path of travel of said hollow needle for being rendered inoperative thereby in its travel to said extended position whereupon said passage means now establishes communication between said receiving chamber and said hollow needle whereby injection liquid flows from said receiving chamber to said hollow needle under the pressure applied to said injection liquid by said second piston means.
Claim 2
Dependent Claim
227 words
A hypodermic syringe comprising a housing having a needle chamber and a receiving chamber, a hollow needle mounted for slidable displacement in said needle chamber in a retracted position, said receiving chamber being sealed and containing an injection liquid therein, first piston means acting on said hollow needle for displacing said needle to an extended position in which the needle projects from said housing for piercing the skin of a subject against which the housing is placed, second piston means in said receiving chamber for acting on said injection liquid to pressurize the same, holder means holding said first and second piston means in respective retracted position, passage means connecting said first and second chambers, closure means normally closing said passage means, and actuator means for releasing said holder means to permit said first and second piston means to move to respective extended positions in which the hollow needle is displaced to its extended position and the injection liquid is pressurized, said closure means being positioned in the path of travel of said hollow needle for being rendered inoperative thereby in its travel to said extended position whereupon said passage means now establishes communication between said receiving chamber and said hollow needle whereby injection liquid flows from said receiving chamber to said hollow needle under the pressure applied to said injection liquid by said second piston means.
Claim 3
Dependent Claim
47 words
A syringe as claimed in claim 1 wherein said hollow piston is provided with perforation means which connect with said passage means when said hollow needle is displaced to said extended position whereby said injection liquid can flow from said injection chamber directly into said hollow needle.
Claim 4
Dependent Claim
33 words
A syringe as claimed in claim 1 wherein said actuator means and said holder means are cooperatively constructed and engaged such that said first piston means is activated before said second piston means.
Claim 5
Dependent Claim
27 words
A syringe as claimed in claim 1 wherein each said piston means comprises a respective associated spring means acting to displace the piston means to extended position.
Claim 6
Dependent Claim
49 words
A syringe as claimed in claim 3 wherein said actuator means comprises a pivotal lever having a first portion engaged with said first piston means and a second portion engaged with said second piston means such that pivotal movement of said lever releases said first and second piston means.
Claim 7
Dependent Claim
19 words
A syringe as claimed in claim 5 wherein said pivotal lever includes an engaging portion for pivoting said lever.
Claim 8
Dependent Claim
32 words
A syringe as claimed in claim 6 wherein said first and second portions of said lever are constructed to first release said first piston means and then release said second piston means.
Claim 9
Dependent Claim
22 words
A syringe as claimed in claim 6 comprising a removable cover on said housing enclosing said pivotal lever and said holding means.
Claim 10
Dependent Claim
51 words
A syringe as claimed in claim 6 comprising a manually engageable element coupled to said second piston means for manually holding said second piston means in retracted position after release thereof by said holder means thereby permitting manual control of the displacement of said second piston means to its extended position.
Claim 11
Dependent Claim
31 words
A syringe as claimed in claim 1 wherein said needle chamber and receiving chamber are disposed in parallel adjacent relation, said first and second piston means being movable along parallel paths.
Claim 12
Dependent Claim
51 words
A syringe as claimed in claim 1 wherein said needle chamber has an end wall facing said hollow needle which is constructed for being pierced by said needle as it travels to said extended position, said end wall serving as an abutment for holding said hollow needle in said extended position.