Method of producing a syringe barrel for medical purposes
The equipping of syringe barrels ( 11 ) with needles ( 25 ) takes place before the injection of the plastic, in which the needles ( 25 ) are introduced through the fixed part ( 5 ) of the injection mold ( 1 ) by a suitable transport device (transport rollers 33 ).
1. Method for producing a syringe barrel with an inserted needle for medical purposes, comprising:
inserting a needle into a cavity of an injection mold prior to injection of plastic wherein the needle is inserted by a rear end thereof into the cavity from outside the injection mold from the rear through a guide tube in a fixed part of the injection mold;
holding the needle at its front end in a region of a point of the needle during an injection cycle by a force acting in the direction of insertion;
filling the cavity with injection of plastic therein to form a syringe barrel with the needle;
ejecting of the syringe barrel together with the insert molded needle; and
inserting another needle from outside the injection mold from the rear through the guide tube during or after the ejection.
2. Method according to claim 1 , wherein with closing of the injection mold the needle is already introduced therein.
3. Method according to claim 1 , further comprising transport means performing at least one of releasing the needle at the end of an injection cycle from a holding and clamping position and pushing the needle further forward from the fixed part during the ejection.
4. Apparatus for producing a syringe barrel with an inserted needle for medical purposes, comprising an injection mold having a moveable part and a fixed part, and a transport means arranged behind the fixed part, the transport means configured to insert individual needles into a cavity defined between the moveable and fixed parts of the injection mold through a guide tube in the fixed part.
5. Apparatus according to claim 4 , wherein the moveable part includes a core for molding the syringe barrel, a blind hole is formed at a free end of the core for guiding and receiving the rear end of the needle.
6. Apparatus according to claim 5 , wherein the blind hole is dimensioned such that the rear end of the needle is tightly enclosed.
7. Method according to claim 1 , wherein inserting of the needle includes a sliding thereof through the guide tube in the fixed part of the injection mold by a transport means that is arranged behind the fixed part of the injection mold, wherein the rear end of the needle is introduced into a blind hole at the front end of a core, which is held on a movable part of the injection mold, and is retained therein by the transport means.
8. Method according to claim 7 , wherein the transport means performs at least one of releasing the needle at the end of the injection cycle from a holding and clamping position and pushing the needle further forward from the fixed part during the ejection.