Method of injecting fluid into animals

• US 6,315,758 B1
• Filed: 08/29/1997
• Issued: 11/13/2001
• Est. Priority Date: 06/07/1991
• Status: Expired due to Fees

• Current Assignee: Liebel-Flarsheim Company (Mallinckrodt plc)
• Original Assignee: Liebel-Flarsheim Company (Mallinckrodt plc)
• Inventors: Fago, Frank M., Neer, Charles, Goethel, James H., Dieterlen, Paul E.
• Primary Examiner(s): STRIGHT, RONALD K
• Application Number:
  US08/924,017
• Time in Patent Office: 1,537 Days
• Field of Search: 604/154, 604/155, 604/131, 604/151, 604/152, 604/232, 604/234, 604/218, 604/181, 604/187, 604/228
• US Class Current: 604/152
• CPC Class Codes: A61M 2250/00 Specially adapted for animals
• CPC Class Codes: A61M 5/14546 Front-loading type injectors
• CPC Class Codes: A61M 5/14566 with a replaceable reservoir for receiving a piston rod of the pump
• CPC Class Codes: A61M 5/1458 Means for capture of the plunger flange
• CPC Class Codes: Y10S 128/01 Motorized syringe

Abstract

An animal fluid injector, replaceable syringe and method of replacement of the syringe in the injector are provided in which the syringe is loadable and unloadable into and from the injector through the open front end of a pressure jacket of the injector, thereby permitting replacement without retraction of the syringe plunger drive or disconnection of the injection tubing. The syringe is provided with a pressure restraining front end, such as an integral or removable cap with structure such as threads that lock the syringe to the front end of the jacket by mating with threads on the jacket. A mechanism in the injector, which includes, for example, a key or cam ring operated by a lever with one hand of an operator, interacts with structure such asymmetrically spaced notches on the back end of the syringe to, for example, rotate the syringe and simultaneously translate or rotate a coupling on the syringe plunger into and out of engagement with the plunger drive in the injector.

Claims

1. A method of loading a tubular replacement syringe into a power injector for injecting fluid into an animal, the method comprising the steps of:

providing a power injector having;

a syringe mount adapted to receive a rearward end of a syringe having a generally circular exterior, and

a ram having a motor linked thereto and operable to reciprocate the ram along a line extending generally through the mount; and

providing a hollow tubular syringe that includes;

a cylindrical body having an axis, a generally circular exterior, a rearward end and a closed forward end with a fluid discharge orifice therein, and

a plunger axially slidable in the body and in sealable contact therewith;

providing the syringe mount of the injector and the generally circular exterior of the syringe each with mating locking structure fixed thereto and configured to lock the syringe to the mount upon the rotation of the syringe;

then;

mounting the syringe to the injector by generally rearward axial movement of the syringe toward the injector followed by bodily rotating the syringe, including the cylindrical body thereof on the axis of the body relative to the injector to thereby lock the body of the syringe at the generally circular exterior thereof with the mating locking structure to the mount of the injector; and

coupling the plunger to the ram so that the plunger is capable of being driven forwardly or rearwardly by the ram.

2. The method of claim 1 wherein:

the step of coupling the plunger with the ram is performed by the rotating of the syringe relative to the injector and occurs simultaneously with the locking of the body to the mount.

3. The method of claim 1 wherein:

the power injector providing step includes the step of providing linkage for affecting a translation of the ram relative to the syringe mount when a syringe is rotated relative to the mount; and

the coupling of the plunger with the ram is performed by a translating motion of the plunger relative to the ram concurrent with the rotation of the syringe relative to the injector.

4. A method of loading a tubular replacement syringe into a power injector for injecting fluid into an animal, the method comprising the steps of:

providing a power injector having;

a syringe mount adapted to receive a syringe having a generally circular exterior, and

a ram having a motor linked thereto and operable to reciprocate the ram along a line extending generally through the mount; and

providing a hollow tubular syringe having;

a cylindrical body having an axis, a generally circular exterior, a rearward end and a closed forward end with a fluid discharge orifice therein, and

a plunger axially slidable in the body and in fluid sealing contact with the body;

providing the syringe mount of the injector and the generally circular exterior of the syringe each with mating locking structure fixed thereto and configured to lock the syringe to the mount upon the rotation of the syringe;

providing the ram of the injector and the plunger of the syringe each with mating coupling structure thereon configured to couple the plunger to the ram and to uncouple the syringe from the ram upon movement of the plunger relative to the ram;

then;

mounting the syringe to the injector by bodily rotating the syringe, including the cylindrical body thereof, on the axis of the body relative to the injector to both lock the syringe to the injector with the mating locking structure and couple the plunger to the ram so that the plunger will move forward or backward with the ram.

5. The method of claim 4 wherein:

the power injector providing step includes the step of providing linkage for affecting a translation of the ram relative to the syringe mount when a syringe is rotated relative to the mount; and

the coupling of the plunger with the ram is performed by a translating motion of the plunger relative to the ram concurrent with the rotation of the syringe relative to the injector.