Patent ID: 8684977
Filing Date: 2014-04-01
Classification: A61M

Abstract:
1. A combined container-syringe comprising: a combined container-syringe body that has an outer tube inside of which a drug solution is filled, a cylindrical tip which is attached to a front end portion of the outer tube and to a front end portion of which an injection needle is attached, and a finger grip that is attached to a rear end portion of the outer tube; a cylindrical safety device which is attached on an outer circumferential surface of the outer tube in a freely sliding manner; a first retaining member that fixes the safety device in a disengageable manner at a first position where the safety device is separated from the injection needle; a second retaining member that fixes the safety device at a second position where the safety device covers the injection needle; a biasing member that biases the safety device in the direction from the first position to the second position; and a latch releasing member that releases the engagement by the first retaining member, wherein the finger grip has a cylindrical fitting portion that is attached to the rear end portion of the outer tube, and a flange surface that protrudes outward in a radial direction of the combined container-syringe body from an outer circumferential surface of a rear end portion of the fitting portion and faces backward; the first retaining member has an engagement portion that is provided in a rear end portion of the safety device and a latch portion that is provided on the outer circumferential surface of the fitting portion and is engaged with the engagement portion; the latch releasing member is a slide member that is capable of sliding on the flange surface along the radial direction of the combined container-syringe body from a waiting position where the slide member is disposed at a position closer to the outside in the radial direction of the combined container-syringe body to a releasing position where the slide member is disposed at a position closer to the inside in the radial direction of the combined container-syringe body; the slide member releases the engagement of the latch portion with the engagement portion when the slide member slides from the waiting position to the releasing position; the engagement portion protrudes parallel to an axis of the combined container-syringe body from the rear end portion of the safety device and is elastically deformable in the radial direction of the combined container-syringe body; the slide member has a sloping side surface that slopes inward in the radial direction of the combined container-syringe body from the waiting position side to the releasing position side and is capable of abutting an inner surface of the engagement portion; the sloping side surface presses the engagement portion such that the engagement portion is elastically deformed outward in the radial direction of the combined container-syringe body when the slide member moves to the releasing position; the combined container-syringe further comprising: a plunger rod which extends along the axis of the combined container-syringe body, is inserted into the outer tube from the rear end side, and is pushed forward at the time of injection, wherein the slide member has a penetrating portion having a larger-diameter hole that penetrates the slide member along the axis when the slide member is positioned at the waiting position, and a smaller-diameter slit that penetrates the slide member along the axis when the slide member is positioned at the waiting position, extends along a direction to which the sliding member slides, and is connected with the larger-diameter hole; the plunger rod comprises: a larger-diameter rod portion that is capable of being inserted into the larger-diameter hole but is not capable of being inserted into the smaller-diameter slit, and a smaller-diameter rod portion that is capable of being inserted into the larger-diameter hole and the smaller-diameter slit; the larger-diameter rod portion is inserted through the penetrating portion before injection when the plunger rod is positioned at the most rear end side and at the time of injection when the plunger rod is pushed forward; and the smaller-diameter rod portion is inserted through the penetrating portion after completion of injection when the plunger rod is pushed to the front-most end side.