Abstract: The invention concerns a needleless syringe (1) comprising a trigger, a gas generator (2) prolonged by a gas expansion chamber (3), a system for retaining particles and an ejection tube (4). The invention is characterised in that the particles are housed outside the ejection tube conduit (4) and the gases cause the particles to reach inside said tube (4) by displacing a plunger (13), prior to speeding them up by wave shock inside the tube (4).

Abstract: The technical field of the invention is that of pre-filled and disposable needleless syringes, used for intradermal, subcutaneous and intramuscular injections of liquid active principle for therapeutic use in human and veterinary medicine. The inventive syringes (1) are mainly characterized in that they function with a pyrotechnic charge (6) consisting of a mixture of powder with high burning rate and a powder with low burning rate. Indeed, the combustion of the powder with a high burning rate enables to communicate instantly, through a piston (3), a very high speed to the active principle (4), whereas the combustion of the powder with a low burning rate enables to maintain a threshold pressure level to proceed with the injection, so as to ensure that the active principle (4) penetrates through the skin. Thus, the injection is properly and homogeneously without any loss of active liquid (4).

Abstract: The invention relates to a needless syringe (1), comprising in succession, a gas generator (2), a gas expansion chamber (3) and a means for retaining the particles of an active agent, comprising at least one lid (8) which breaks under the influence of the gas coming from the generator (2). The main characteristic of the inventive syringe (1) is that the tube (6) has a cylindrical upstream part in which the means retaining the particles are fixed, said upstream part having a substantially constant cross-section over a length that is more than twice its inner diameter.

Abstract: The technical field of the invention is that of needleless syringes used for injecting active principles in powder form for therapeutic purposes. The invention concerns a needleless syringe (1) comprising successively a gas generator (2), a gas expanding chamber (3), means for retaining active particles and an ejection tube (4). The invention is characterised in that the particle retaining means consists of an inner seal (14) having at least a cavity (15), the inner seal (14) serves both to contain the active principle and to generate a shock wave when it is ruptured.

Abstract: The invention concerns the field of needleless syringe having an injector with several ducts. The problem that needs to be solved is the long term compatibility of the injector with the liquid active principle. For that purpose the syringe (1) comprises a cylindrical reservoir (2), closed at its upstream part by a closure element (3) capable of being moved by driving means (70), and closed at its downstream part by an injector (4) comprising at least an injection duct and said reservoir being secured to the body (8) of the syringe, said syringe is such that the diaphragm (5), compatible with the active principle, isolates the latter from the injector (4) and said diaphragm can be passed through by the liquid (6) when pressurised for injection.

Abstract: The invention concerns the field of needleless syringe having an injector with several ducts. The problem that needs to be solved is the long term compatibility of the injector with the liquid active principle. For that purpose the syringe (1) comprises a cylindrical reservoir (2), closed at its upstream part by a closure element (3) capable of being moved by driving means (70), and closed at its downstream part by an injector (4) comprising at least an injection duct and said reservoir being secured to the body (8) of the syringe, said syringe is such that the diaphragm (5), compatible with the active principle, isolates the latter from the injector (4) and said diaphragm can be passed through by the liquid (6) when pressurised for injection.

Abstract: The technical field of the invention is that of pre-filled and disposable needleless syringes, used for intradermal, subcutaneous and intramuscular injections of liquid active principle for therapeutic use in human and veterinary medicine. The inventive syringes (1) are mainly characterised in that they function with a pyrotechnic charge (6) consisting of a mixture of powder with high burning rate and a powder with low burning rate. Indeed, the combustion of the powder with a high burning rate enables to communicate instantly, through a piston (3), a very high speed to the active principle (4), whereas the combustion of the powder with a low burning rate enables to maintain a threshold pressure level to proceed with the injection, so as to ensure that the active principle (4) penetrates through the skin. Thus, the injection is properly and homogeneously without any loss of active liquid (4).

Abstract: The invention concerns the field of needless syringe for injecting liquid active principle for therapeutic purposes. It concerns a syringe wherein the active principle (1, 10) is initially placed between an injector (2, 22) comprising at least an injection duct (3, 23) contacted with the skin and a mobile wall (4, 24) separated from thrusting means (5, 25) displaced by gases of propellant generator (7, 27) pressurising and expelling the active principle. Said syringe aims at quickly providing a high expelling speed of the liquid to efficiently perforate the skin and improve bioavailability. Said syringe is characterised in that said thrusting means (5, 25) comprising temporary retention device (6, 26) deactivated by the operation of the propellant generator (7, 27).

Abstract: The invention concerns the technical field of needleless syringes for injecting an active principle for therapeutic purposes. More particularly, it concerns a needleless syringe for injecting an active principle (7, 70) initially set between an injector (1, 10) comprising at least an injection nozzle (50, 50′, 60′) contacted with the skin and a wall (8) mobile under the effect of a propelling system (9) pressurizing and expelling the active principle through the injector located at the downstream end (2, 20) of the syringe. In order to produce nozzles passing through a considerable injector thickness and to control the jet coherence distance, said injector (1, 10) comprises a support (3, 21) with at least a housing (4, 40) wherein are stacked plates (51, 61, 91, 51′, 71′, 91′, 52, 92) each comprising an equal number of orifices aligned to form at least a nozzle (50, 50′, 60′) through the stack.

Abstract: The invention concerns the technical field of needleless syringes for injecting an active principle through the skin. More particularly, the invention concerns a needleless syringe provided with a piezoelectric crystal and a triggering device comprising a triggering member and impacting means and, on a triggering device particularly adapted to needleless syringes. The invention is mainly characterized in that the impacting means comprises a latch maintained under elastic stress by being blocked against a stop element and the triggering member is capable of moving the latch to release it, so that it is urged to strike the piezoelectric crystal. Then, the crystal produces an electric arc designed to initiate a pyrotechnic charge whereof the combustion gases will help to expel the active principle contained in the syringe.

Abstract: A needleless syringe equipped with an initiating device comprising a triggering device and a pyrotechnic charge, wherein the triggering device contains a triggering member connected to a friction igniter that initiates the pyrotechnic charge by friction. An advantage of the invention is that the syringe produces very limited amounts of noise during operation.