Pellet injector

• US 4,673,387 A
• Filed: 04/30/1986
• Issued: 06/16/1987
• Est. Priority Date: 05/06/1985
• Status: Expired due to Fees

• Current Assignee: NJ Phillips Pty Ltd. (Province of Québec)
• Original Assignee: NJ Phillips Pty Ltd. (Province of Québec)
• Inventors: Phillips, Ian R., Bunyan, Glen W., Lodge, Robert H.
• Primary Examiner(s): Yasko, John D.
• Application Number:
  US06/858,065
• Time in Patent Office: 412 Days
• Field of Search: 604/61, 604/62, 604/63, 604/64, 604/57, 604/59, 604/218, 221/78, 221/79, 221/81, 221/88
• US Class Current: 604/62
• CPC Class Codes: A61M 37/0069 Devices for implanting pellets, e.g. markers or solid medicaments for introducing of radioactive sources for interstitial radiation therapy, i.e. brachytherapy A61N5/1027

Abstract

An injector to dispense pellets from a magazine rotatably supported in the injector, the injector has an indexing mechanism which causes indexing of the magazine, with the indexing mechanism being actuated by an injection rod which injects the pellets, and with the indexing operation taking place upon return of the indexing rod to its rest position.

Claims

1. An injector to dispense pellets from a magazine to be supported by the injector, said magazine having a plurality of spaced pellet receiving parallel passages extending therethrough, said injector comprising a body, an injector rod slidably mounted in said body so as to be movable along a predetermined path from a retracted position to an inject position, said body having a mounting to support said magazine, said mounting being positioned to locate said magazine with one of said passages extending along said path so that said injector rod passes through said magazine so as to move a pellet therefrom to be injected, an operator manipulable trigger mounted on said body and operatively associated with said rod to cause movement thereof along said path, and indexing means actuated by said rod to cause indexing of said magazine, said indexing means including an indexing link movably mounted on said body and movable in a plane generally transverse of said path, said link being positioned to be engaged by said rod and to be moved thereby between a first position with said link projecting into said path and a second position clear of said path, means biassing said link to said first position, and ratchet means connected to said link so as to move therewith, said ratchet means being biassed to engage said magazine to cause indexing thereof when said link is moved from said second position to said first position.

2. The injector of claim 1 wherein said indexing means further includes an indexing arm pivotally supported on said body so as to be pivotable about an axis generally parallel to said path, pivot means pivotally connecting said link and said arm so that movement of said link causes pivoting of said arm, and wherein said ratchet means is mounted on the extremity of said arm remote from said pivot means.

3. The injector of claim 2 wherein said magazine is pivotally mounted so as to be rotatable about an axis parallel to said path but spaced therefrom, and said arm is pivotally mounted so as to pivot about the axis of said magazine.

4. The injector of claim 1 further including a retaining member movable between a retaining position engaging said link and preventing movement thereof from the second to the first positions thereof, and a release position allowing movement of said link, and means to cause movement of said retaining member from the retaining position to the release position as said rod moves from the inject position to the retract position.

5. The injector of claim 4 including a release slide slidably mounted in said body so as to extend generally parallel to and adjacent said rod, said release slide being positioned to engage said retaining member to cause the movement thereof to said release position, and being engaged by said rod as it is moved. from said inject position to said retract position.

6. The injector of claim 5 further including means biassing said retaining member to the retaining position thereof.

7. A magazine to be used with the injector of claim 1, said magazine being of cylindrical configuration and having a plurality of longitudinally extending pellet receiving passages equally angularly arranged about the axis of the magazine and at a fixed radius relative thereto, and a plurality of indexing projections equally angularly spaced about the longitudinal axis of the magazine and adapted to be engaged by the ratchet means of said injector, with the number of said passages being equal to the number of said projections.

8. The magazine of claim 7 wherein said projections are equiangularly spaced between adjacent passages.

9. An injector to dispense pellets from a magazine to be supported by the injector, said magazine having a plurality of spaced pellets receiving parallel passages extending therethrough, said injector comprising a body, an injector rod slidably mounted in said body so as to be movable along a predetermined path from a retracted position to an inject position, said body having a mounting to support said magazine, said mounting being positioned to locate said magazine with one of said passages extending along said path so that said injector rod passes through said magazine so as to move a pellet therefrom to be injected, an operator manipulable trigger mounted on said body and operatively associated with said rod to cause movement thereof along said path and indexing means actuated by said rod to cause indexing of said magazine, said indexing means including an indexing link movably mounted on said body and movable in a plane generally transverse of said path, said link being positioned to be engaged by said rod and to be moved thereby between a first position with said link projecting into said path and a second position clear of said path, means biassing said link to said first position, and ratchet means connected to said link so as to move therewith, said ratchet means being biassed to engage said magazine to cause indexing thereof when said link is moved in a first direction between the first and second positions of said link, while said magazine remains stationary during movement of said link in the opposite direction to said first direction between the first and second positions of said link.

10. The injector of claim 9 wherein said link is moved in said first direction when moving from said second position to said first position of said link.