Injection device and method

• US 4,267,836 A
• Filed: 04/16/1979
• Issued: 05/19/1981
• Est. Priority Date: 11/12/1976
• Status: Expired due to Term

• Current Assignee: Douglass G. Whitney, John K. Martin III
• Original Assignee: Douglass G. Whitney, John K. Martin III
• Inventors: Whitney, Douglass G., Martin, John K. III
• Primary Examiner(s): Truluck, Dalton L.
• Application Number:
  US06/030,277
• Time in Patent Office: 764 Days
• Field of Search: 128/214 F, 128/218 A, 128/215, 128/218 D, 128/218 F
• US Class Current: 604/135
• CPC Class Codes: A61M 2005/14506 mechanically driven, e.g. spring or clockwork
• CPC Class Codes: A61M 2005/14513 with secondary fluid driving or regulating the infusion
• CPC Class Codes: A61M 5/14546 Front-loading type injectors

Abstract

Method and apparatus for injecting fluids into patients at a controlled rate from an ampule with a tubular side wall closed at one end with a penetrable plug and a sliding piston in the side wall to force the fluid through an opening in the penetrable member using either a long duration injector with an expelling means to move the ampule piston, drive means for operating the expelling means, and control means for incrementally and successively connecting and disconnecting the drive means to the expelling means or a short duration injector with a spring drive or a fluid pressure drive to move the ampule piston and meter the fluid through a metering device.

Claims

1. An injector to inject fluid into a patient comprising:

an ampule holder defining an ampule receiving chamber therein;

an ampule assembly removably mounted in said ampule receiving chamber in said ampule holder, said ampule assembly including an ampule comprising;

a seamless tubular side wall defining a passage therethrough opening onto opposite ends of said side wall;

a penetrable member closing one end of said passage at one end of said side wall so that a discharge opening from said passage can be made by penetrating said penetrable member; and

a piston member slidably received in said passage from that end of said tubular side wall opposite said penetrable member and in sealing engagement with said tubular side wall so that a fluid chamber is defined by and between said tubular side wall, said piston member and said penetrable member and filled with the fluid whereby the fluid can be dispensed from said fluid chamber upon penetration of said penetrable member to form the discharge opening and forcing said piston member toward said penetrable member;

cap means removably connected to said ampule holder and engaging that end of said ampule at said penetrable member to positively and removably position said ampule in said ampule receiving chamber;

penetrating means carried by said cap means for penetrating said penetrable member on said ampule as an incident to the positioning of said ampule in said ampule holder and for forming a fluid outlet from said fluid chamber through which the fluid is injected into the patient;

a manually engagable externally threaded sleeve member having a projecting end and an opposite end and defining an axially extending ampule receiving passage therein;

said sleeve member threadedly engaging said ampule holder so that, as said sleeve member is screwed into said ampule holder, the projecting end of said sleeve member is moved axially along said ampule receiving chamber in said ampule holder and that end of said ampule opposite said penetrable member is slidably supported by said sleeve member within said ampule receiving passage therein, said sleeve member including an end wall at said opposite end closing said ampule receiving passage; and

a drive spring assembly extending between said end wall on said sleeve member and said piston, said drive spring assembly including a compressible coil spring mounted on said end wall of said sleeve member and having a projecting end extending axially of said sleeve member within said ampule receiving passage toward said piston, said drive spring assembly further including a drive plunger on the projecting end of said coil spring operatively engaging said piston so that, as said coil spring is compressed, the spring force urges said piston toward said penetrable member to force fluid out the fluid outlet, the length of said coil spring selected so that, as said sleeve member is manually screwed into said ampule holder, the compression of said coil spring is increased to selectively increase the effective spring force urging said piston toward said penetrable member.

2. The injector of claim 1 further including:

an ampule adapter defining an ampule passage therein centered in said adapter and sized to slidably receive said side wall of said ampule therein to maintain said ampule centered in said ampule adapter;

said ampule adapter slidably received in said chamber in said ampule holder, and including first locating means at one end of said ampule adapter to maintain one end of said ampule adapter coaxially centered in said chamber in said ampule holder and second locating means at the opposite end of said ampule adapter to maintain said opposite end of said ampule adapter coaxially centered in said chamber in said ampule holder to coaxially center said ampule in said ampule receiving chamber in said ampule holder.

3. The injector of claim 1 wherein said penetrating means further includes a piercing needle assembly having a sharpened piercing point thereon coaxially extending into said ampule receiving chamber of said ampule holder to penetrate said penetrable member of said ampule when said ampule is carried in said ampule receiving chamber of said ampule holder to form said fluid outlet from said fluid chamber in said ampule through said piercing needle assembly.

4. The injector of claim 3 further including a cover assembly for enhancing the sterility of said piercing needle comprising:

a penetrable cover member capable of being penetrated by the piercing point on said piercing needle;

positioning means for selectively positioning said penetrable cover member in alignment with the piercing point of said piercing needle so that said penetrable cover member is movable axially of said piercing needle from a non-use position in which the piercing point of said piercing needle is enclosed by said positioning means and said penetrable cover member to a use position in which the piercing point of said piercing needle is exposed by penetrating the penetrable cover member; and

urging means for urging said penetrable cover member toward its non-use position.

5. The injector of claim 1 further including metering means operatively connected to said piercing means to regulate the flow of fluid from said ampule.

6. The injector of claim 5 wherein said metering means includes a porous member for regulating the flow of the fluid from said ampule and gasket means operatively connecting said porous member to said penetrating means, said gasket means having a first flushing position in which the fluid from said ampule is allowed to bypass said porous member without regulation and a second metering position in which the fluid from said ampule must pass through said porous member to regulate the flow thereof from said ampule.