Syringes for medical purposes comprise a syringe barrel, at the front end of which is arranged a needle and a piston, which is pulled up with the medium to be injected on the one hand and is later injected. In most cases, the needle is supplied packed separately from the syringe or from the syringe barrel and piston. However, it is also known, in particular for syringes for injections of inoculants and the like, to manufacture this with the needle already attached. In the manufacture of such syringes, the needle pointed at the front end in the case of an open mold with a handling unit is led through the cavity into the injection mold and then partially enclosed by the liquid plastic in the injection process. To insert the needle through the open mold it is necessary to configure the needles in an appropriate manner, so that they can be detected by the handling unit and then led between the open mold in the cavity. This leads to a reduction of cycles per unit of time and consequently higher production costs.
Further, a medical syringe with integrated needle is known from WO 2012/003221 A1. The needle is held positioned with clamping jaws during the injection process in such a way that the end opposite the sharpened end of the needle definitely does not protrude beyond the inner wall of the syringe barrel. Preferably, the inner end of the needle is even held slightly recessed, so that even in the event of a possible shrinking of the plastic of the syringe barrel the end does not project into the interior space and therefore does not hinder the full expression of the injection liquid. In addition, the bore of the needle is held closed during the injection process by a thread or wire (strand), to prevent the penetration of plastic into the needle. The manufacture of such a syringe barrel with an integrated needle is very costly.
USPTO Backgrounds
USPTO Backgrounds