Needle-equipped syringe and injection molding die for the same

Patent metadata

Field	Value
Publication number	US-2016199591-A1
Application number	US-201615074721-A
Country	US
Kind code	A1
Filing date	Mar 18, 2016
Priority date	Sep 19, 2013
Publication date	Jul 14, 2016
Grant date	—

Abstract

A needle-equipped syringe reduces an inclination of a needle by reducing an inclination of a core pin when insert molding is performed. The needle-equipped syringe includes a barrel formed using a resin and having a cylindrical body, a nozzle part provided at a distal end of the body, and an opening part provided at a proximal end of the body; and an injection needle held by the nozzle part. The injection needle and the barrel are integrally molded so that an axis of the injection needle is substantially parallel to an axis of the body. The body has a thick part and a thin part located at a proximal end of the body at opposing positions across the axis of the body. At the proximal end of the body, an axis of an inner surface of the body is offset from an axis of an outer surface of the body.

First claim

1 . A needle-equipped syringe comprising:
a barrel formed using a resin and having a cylindrical body, a nozzle part provided at a distal end of the body, and an opening part provided at a proximal end of the body; and an injection needle configured to be held by the nozzle part, wherein the injection needle and the barrel are integrally molded so that an axis of the injection needle is substantially parallel to an axis of the body, the body has a thick part and a thin part, which are located at a proximal end of the body at positions opposed to each other across the axis of the body, and at the proximal end of the body, an axis of an inner surface of the body is offset from an axis of an outer surface of the body.

2 . The needle-equipped syringe according to claim 1 , wherein a single gate mark generated at a time of molding the barrel is provided on the opening part of the barrel or the outer surface of the body, and the thin part is provided at a side of the gate mark in a circumferential direction of the body.

3 . The needle-equipped syringe according to claim 2 , wherein:
the opening part includes a flange extending perpendicularly to the axis of the body, and the single gate mark is provided on an outer surface of the flange.

4 . The needle-equipped syringe according to claim 1 , wherein a length from the distal end of the body to the proximal end of the body in the axis direction of the body is four to twelve times an internal diameter of the proximal end of the body.

5 . The needle-equipped syringe according to claim 1 , wherein a difference between a thickness of the thick part and a thickness of the thin part is 50 to 500 μm.

6 . The needle-equipped syringe according to claim 1 , wherein an inclination of the axis of the injection needle with respect to the axis of the body is equal to or less than 2°.

7 . An injection molding die for molding a needle-equipped syringe that includes a barrel formed using a resin and having a cylindrical body, a nozzle part provided at the distal end of the body, and an opening part provided at a proximal end of the body; and an injection needle held by the nozzle part, and in which the injection needle and the barrel are integrally molded so that an axis of the injection needle is substantially parallel to an axis of the body, the injection molding die comprising:
a female die having a recessed part for molding an outer surface of the barrel, and a holding part for holding a distal side of the injection needle; a male die having a core pin for molding an inner surface of the barrel, and a holding hole for holding a proximal end of the injection needle distal to the core pin; and a resin injection gate configured to inject the resin into a cavity space formed by the recessed part and the core pin inserted into the recessed part so that the holding hole is positioned in the recessed part, wherein the core pin is inserted into the recessed part so as to be offset with respect to an axis of the recessed part.

8 . The injection molding die according to claim 7 , wherein:
the resin injection gate is formed as a single part configured to mold an outer surface of the body or a part configured to mold an outer surface of the opening part, and the core pin is inserted into the recessed part so as to be offset to a side of the resin injection gate with respect to the axis of the recessed part.

9 . The injection molding die according to claim 8 , wherein the resin injection gate is formed as a single part configured to mold an outer surface of a flange of the opening part extending perpendicularly to the axis of the body.

10 . The injection molding die according to claim 7 , wherein a length of the core pin in an axis direction of the core pin is four to twelve times a diameter of the core pin.

11 . The injection molding die according to claim 7 , wherein the injection molding die is a hot runner die that includes a heater for heating a runner reaching the resin injection gate.

12 . The injection molding die according to claim 7 , wherein the holding part holds a side of the injection needle distal to the nozzle part.

13 . A method of manufacturing a needle-equipped syringe using an injection molding die, the needle-equipped syringe including a barrel formed using a resin and having a cylindrical body, a nozzle part provided at a distal end of the body, and an opening part provided at a proximal end of the body; and an injection needle held by the nozzle part, and in which the injection needle and the barrel are integrally molded so that an axis of the injection needle is substantially parallel to an axis of the body, and the injection molding die including a female die having a recessed part for molding an outer surface of the barrel, and a holding part for holding a distal side of the injection needle; a male die having a core pin for molding an inner surface of the barrel, and a holding hole for holding a proximal end of the injection needle distal to the core pin; and a resin injection gate configured to inject the resin into a cavity space formed by the recessed part and the core pin inserted into the recessed part so that the holding hole is positioned in the recessed part, the method comprising:
inserting the core pin into the recessed part so as to be offset with respect to an axis of the recessed part, wherein the proximal end of the injection needle is held by the holding hole and the distal side of the injection needle is held by the holding part; and molding the barrel by injecting the resin from the resin injection gate into the cavity space.

14 . The method of manufacturing a needle-equipped syringe according to claim 13 , wherein
the core pin is inserted into the recessed part offset with respect to the axis of the recessed part such that a pressure and/or a speed of the resin injected into the cavity space becomes substantially uniform around the core pin in a cross section perpendicular to the axis of the core pin.

15 . The method of manufacturing a needle-equipped syringe according to claim 13 , wherein
the resin injection gate is formed as a single part configured to mold an outer surface of the body or a part configured to mold an outer surface of the opening part, and the core pin is inserted into the recessed part offset to a side of the resin injection gate with respect to the axis of the recessed part.

16 . The method of manufacturing a needle-equipped syringe according to claim 15 , wherein
the barrel is molded by injecting the resin into the cavity space from the resin injection gate which is formed as the single part configured to mold an outer surface of a flange of the opening part.

17 . The manufacturing method for a needle-equipped syringe according to claim 13 , wherein
the holding part holds a side of the injection needle distal to the nozzle part.

18 . The manufacturing method for a needle-equipped syringe according to claim 13 , wherein
the injection molding die is a hot runner die that includes a heater for heating a runner reaching the resin injection gate, and when the needle-equipped syringe is taken out from the injection molding die, the runner is heated by the heater, and the needle-equipped syringe is separated from the runner.

Assignees

• Terumo Corp

Inventors

• Matsui Takayuki

Classifications

• A61M5/343 Primary

  Connection of needle cannula to needle hub, or directly to syringe nozzle without a needle hub (A61M5/322 takes precedence) · CPC title

• B29C45/2735

  for non-coaxial gates, e.g. for edge gates · CPC title

• B29L2031/7544

  Injection needles, syringes · CPC title

• B29C45/03

  Injection moulding apparatus (transfer moulding B29C45/02) · CPC title

• B29C45/261

  having tubular mould cavities · CPC title