Apparatus for injecting fluid into animals and disposable front loadable syringe therefor

A disposable replacement syringe for a front loadable injector for injecting liquid into an animal, the disposable syringe comprising:

• a hollow elongated tube having a uniform cross-section exterior surface along substantially its entire length to facilitate sliding contact over substantially its entire length with the interior surface of an injector pressure jacket when inserted therein, said tube having a longitudinal axis, a front end containing a front wall having a discharge outlet therein, and a rear end terminating in a rear peripheral edge defining a plunger drive receiving opening;
• a plunger snugly slidable within said tube and having a rearwardly facing coupling thereon engageable with said plunger drive;
• front end locking means permanently fixed to and exposed exteriorly of said tube proximate said front end thereof to facilitate locking of said tube against longitudinal movement with respect to the front of an injector pressure jacket when inserted therein;
• and
• the locking means including thread means fixed to the syringe proximate the front end of the tube.

A disposable replacement syringe for a front loadable injector for injecting liquid into an animal, the disposable syringe comprising:

• a hollow elongated tube having a uniform cross-section exterior surface along substantially its entire length to facilitate sliding contact over substantially its entire length with the interior surface of an injector pressure jacket when inserted therein, said tube having a longitudinal axis, a front end containing a front wall having a discharge outlet therein, and a rear end terminating in a rear peripheral edge defining a plunger drive receiving opening;
• a plunger snugly slidable within said tube and having a rearwardly facing coupling thereon engageable with said plunger drive;
• front end locking means permanently fixed to and exposed exteriorly of said tube proximate said front end thereof to facilitate locking of said tube against longitudinal movement with respect to the front of an injector pressure jacket when inserted therein;
• and
• the locking means including a plurality of internal thread sections collectively spanning less than half of the full circumference of the tube with openings therebetween spanning at least four equally spaced 45.degree. segments of the circumference of the tube.

A disposable replacement syringe for a front loadable injector for injecting liquid into an animal, the disposable syringe comprising:

• a hollow elongated tube having a uniform cross-section exterior surface along substantially its entire length to facilitate sliding contact over substantially its entire length with the interior surface of an injector pressure jacket when inserted therein, said tube having a longitudinal axis, a front end containing a front wall having a discharge outlet therein, and a rear end terminating in a rear peripheral edge defining a plunger drive receiving opening;
• a plunger snugly slidable within said tube and having a rearwardly facing coupling thereon engageable with said plunger drive;
• front end locking means permanently fixed to and exposed exteriorly of said tube proximate said front end thereof to facilitate locking of said tube against longitudinal movement with respect to the front of an injector pressure jacket when inserted therein;
• and
• the front end locking means including screw threads and wherein said cross-section of said tube exterior surface is configured to facilitate rotation of said tube about its longitudinal axis, when located in the injector pressure jacket with said tube exterior surface in snug sliding contact with said injector pressure jacket interior surface, to enable threaded engagement of said front end locking means with the front of an injector pressure jacket to lock said tube against longitudinal movement with respect to the front of the injector pressure jacket.

A disposable replacement syringe for a front loadable injector for injecting liquid into an animal, the disposable syringe comprising:

• a hollow elongated cylindrical tubular body having a fluid holding cavity at least partially contained therein, a front end, and a back end having a circular outer periphery with a plunger drive receiving opening therethrough;
• the tubular body having a circular outer cross-section uniform throughout substantially its entire length thereof thereby being capable of slidable contact with a surrounding cylindrical pressure jacket of a similarly sized circular inner cross-section, the outer shape of the body being of a radius at least as great as that of the circular outer periphery of the back end of the tubular body;
• the front end of the tubular body having a front wall sealed thereto with a fluid discharge outlet therethrough communicating with the cavity, the front wall including pressure restraining structure providing sufficient strength to support the front wall against deformation when fluid at a predetermined operating pressure is contained within the cavity;
• the tubular body having a plunger slidably supported and moveable longitudinally therein between the back end and the front end thereof and forming a fluid tight seal therewith to seal the cavity, the plunger having a rearwardly facing coupling thereon positioned to be engaged by a plunger drive when extended through the opening;
• means on the syringe fixed with respect to the body thereof for restricting the angular orientation of the syringe on the injector about a longitudinal axis of the syringe, the orientation restricting means including at least one peripheral notch at the back end of the body, interrupting the periphery and extending over three unequally spaced kay receiving positions, and engageable with cooperating structure of the injector, the at least one notch includes key receiving spaces positioned and configured around the back end of the body to engage the cooperating structure of the injector at only one angular orientation about the axis;
• locking means permanently fixed to the syringe proximate the front end of the tubular body and connected at least in part to the pressure restraining structure of the front wall of the syringe for locking the body of the syringe against movement with respect to the injector and for providing at least part of the angular orienting means;
• and
• the locking means including internal threads lying outwardly of the body of the syringe and fixed to the syringe proximate the front end of the tubular body, the threads being lockable upon less than a full rotation of the body and configured and positioned to engage cooperating thread receiving structure on the injector in a limited number of angular orientations about the axis and including a plurality of thread sections circumferentially spaced around the tubular body collectively circumferentially spanning less than half of the full circumference of the tubular body with openings therebetween spanning at least four equally spaced 45.degree. segments of the circumference of the body.