Self-administration device for liquid medicine

• US 20100249718A1
• Filed: 03/15/2010
• Published: 09/30/2010
• Est. Priority Date: 03/25/2009
• Status: Active Grant

• Current Assignee: Nipro Corporation
• Original Assignee: Nipro Corporation
• Inventors: Hiejima, Katsuhiro, Ishizaki, Akihiko, Uchimura, Tomohiro
• Granted Patent: US 8,845,591 B2
• Time in Patent Office: Days
• US Class Current: 604/185
• CPC Class Codes: A61M 2005/1405 Patient controlled analgesia [PCA]
• CPC Class Codes: A61M 5/14212 Pumping with an aspiration and an expulsion action
• CPC Class Codes: A61M 5/1424 Manually operated pumps

Abstract

A liquid medicine self-administration device including a flexible reservoir, an operating member, a pushing member to move with respect to the operating member and to induce pressure deformation of the reservoir, and engaging means engages the operating member. With the operating member engaged by the engaging means, the pushing member is relatively moved to the operating member based on restoring force of a spring member to push the reservoir by the pushing member. By disengaging means moving in unison with the pushing member, the engaging means is released from an engaged state with respect to the operating member, when the pushing member has moved to a predetermined location while pushing the reservoir.

Claims

1. A liquid medicine self-administration device comprising:

a housing open at both ends;

a base member having a liquid medicine inlet/outlet port and attached fitting into a first open end of the housing;

a flexible reservoir having an open end and a closed end wherein the open end is closed by the base member, arranged accommodated within the housing with the interior in communication with the liquid medicine inlet/outlet port of the base member and adapted to retain liquid medicine that has been injected therein through the liquid medicine inlet/outlet port;

an operating member inserted through another open end of the housing and adapted to undergo movement into proximity with and away from the reservoir through an operation performed from an outside;

engaging means adapted to engage the operating member when the operating member has moved into proximity with the reservoir and to prevent movement of the operating member;

a pushing member accommodated in the housing interior between the operating member and the reservoir so as to be capable of relative movement with respect to the operating member, and adapted, through relative movement with respect to the operating member, to push against and induce flexural deformation of the reservoir causing liquid medicine inside the reservoir to be expelled from the liquid medicine inlet/outlet port;

a spring member arranged within the housing in such a way as to undergo elastic deformation between the operating member and the pushing member through movement of the operating member into proximity with the reservoir, and to exhibit restoring force from an elastically deformed state in which the operating member has been engaged by the engaging means so that the relative movement of the pushing member with respect to the operating member resulting from the restoring force causes the reservoir to be pushed by the pushing member; and

disengaging means arranged inside the housing so as to be capable of movement in unison with the pushing member and, when the pushing member has moved to a predetermined location while pushing the reservoir, functioning to release the engaging means from an engaged state with respect to the operating member.

2. The liquid medicine self-administration device according to claim 1, wherein the disengaging means is composed of a disengaging projection integrally projecting towards the base member end from the pushing member;

wherein the engaging means includes an engaging portion disposed on the operating member, a flexing member capable of flexural deformation non-displaceably disposed between the reservoir and the pushing member, an engaging claw portion projecting from the flexing member and adapted to engage the engaging portion of the operating member, and a sloping face adapted to be pushed by the disengaging projection when the operating member has moved towards the reservoir end and to bring about flexural deformation of the flexing member; and

wherein the engaging claw portion is released from the engaged state with respect to the engaging portion of the operating member through flexural deformation of the flexing member in association with pushing of the sloping face by the disengaging projection.

3. The liquid medicine self-administration device according to claim 2, wherein the flexing member is composed of a split ring;

and the engaging claw portion is released from the engaged state with respect to the engaging portion of the operating member through flexion and diameter constriction of the split ring brought about by the disengaging projection of the pushing member pushing against the sloping face.

4. The liquid medicine self-administration device according to claim 2, wherein the engaging means is situated housed inside the housing having a window;

and the operating member is furnished with an operating projection that projects to the housing exterior through the window so that, with the engaging claw portion in the engaged state with respect to the engaging portion of the operating member, the flexing member undergoes flexural deformation when the operating projection is pushed from the outside, in order to release the engaging claw portion from the engaged state with respect to the engaging portion of the operating member.

5. The liquid medicine self-administration device according to claim 1, wherein after the engaging means is released from the engaged state with respect to the operating member by the disengaging means, the reservoir automatically refill with the liquid medicine.

6. The liquid medicine self-administration device according to claim 2, wherein the flexing member is composed of a flexing piece whose basal end is disposed at a fixed location inside the housing so as to extend in an axial direction;

and the engaging claw portion is released from the engaged state with respect to the engaging portion of the operating member through flexural deformation of the flexing piece in an axis-perpendicular direction brought about by the disengaging projection of the pushing member pushing against the sloping face.