Intravenous catheter with needle guard

intravenous catheter device with a catheter (24) shaped tube having a proximal end with a potacath (26) with a needle (16) which can be introduced into the catheter (24) having a proximal end a needle holder (12), while the needle holder (12) engages the potacath (26) so that a tip (18) protrudes at the distal end of the needle (16) of the catheter (24 ), CONUN protector (120) needle on a piece displaceable on the needle (16), disposed in a cavity (27) of potacath (26) and having a coupling element which, on withdrawing the needle (16) relative to the catheter (24) engages with an irregularity (138) of the needle (16) with two bulges (138a) oriented in opposite directions and perpendicularly to them two crushing (138b) are created similarly situated faced to remove the protector (120) needle proximal end of potacath (26), while the protector (120) needle has, in arms (122, 124) located opposite each other, curves (128), which rely on the inner wall of potacath and lips (132) at the free ends of the arms, pressed from opposite sides against the outer wall of the needle (16), characterized in that the cavity (27) of potacath (26) protrudes projection (136a, 136b, 136c, 136d) forming a retainer shield (120) needle, which is constructed in a generally ring shaped and extends at least over two diametrical points potacath (26) while, when introducing the protector (120) needle in potacath curves (128) of the arms are elastically compressed by the projection and then surround the projection to retain the needle guard in potacath while lips (132) pressed against the wall of the needle and to remove the needle, the needle tip passes the lips (132) so that the lips (132) pivoted elastically inwards and cover the needle tip , while the curves (12) are released into the projection and the needle guard can be removed together with the needle potacath.