One-way clutch mechanisms and injector devices

• US 20030050609A1
• Filed: 09/18/2002
• Published: 03/13/2003
• Est. Priority Date: 03/24/2000
• Status: Active Grant

• Current Assignee: Bernard Sams
• Original Assignee: Bernard Sams
• Inventors: Sams, Bernard
• Granted Patent: US 6,899,698 B2
• Time in Patent Office: Days
• US Class Current: 604/208
• CPC Class Codes: A61M 2005/3125 specific display means, e.g. to indicate dose setting
• CPC Class Codes: A61M 5/20 Automatic syringes, e.g. with automatically actuated piston rod, with automatic needle injection, filling automatically A61M5/142 , A61M5/46 take precedence; hypodermic projectiles F42B12/54
• CPC Class Codes: A61M 5/31538 Permanent blocking, e.g. by medical personnel
• CPC Class Codes: A61M 5/31541 Means preventing setting of a dose beyond the amount remaining in the cartridge
• CPC Class Codes: A61M 5/31543 piston rod reset means, i.e. means for causing or facilitating retraction of piston rod to its starting position during cartridge change
• CPC Class Codes: A61M 5/31551 including axial movement of dose setting member
• CPC Class Codes: A61M 5/31553 without axial movement of dose setting member
• CPC Class Codes: A61M 5/3156 using volume steps only adjustable in discrete intervals, i.e. individually distinct intervals
• CPC Class Codes: A61M 5/31578 based on axial translation, i.e. components directly operatively associated and axially moved with plunger rod
• CPC Class Codes: A61M 5/3158 performed by axially moving actuator operated by user, e.g. an injection button
• CPC Class Codes: A61M 5/31593 Multi-dose, i.e. individually set dose repeatedly administered from the same medicament reservoir

Abstract

An incrementing mechanism suitable for use in a medical injector device has a driving member (11, 23) rotatably and slidably mounted within a tubular body (10) and arranged to advance an elongate element (12) in one direction with respect to the tubular body (10). A one-way clutch is defined by a channel (21) extending along the element (12), a generally conical surface (24) formed internally on the driving member (23) and surrounding the element (12), a blocking clutch member (22) located in the channel (21) and engageable with the conical surface (24), and freeing means adapted to disengage the clutch by lifting the clutch member (22) out of engagement with the conical surface so as to disconnect the driving member (23) from the element (12). The freeing means comprises a pressure component (25) held against rotation with respect to the element (12) and arranged to engage the clutch member (22), a spring (27) acting on the pressure component (25) to urge it away from its clutch disengaging position, and two sets of inter-engageable teeth (30, 31) formed respectively around the driving member (23) and around the pressure component (25), whereby rotation of the driving member (11, 23) with respect to the pressure component (25) causes the teeth (30, 31) of the two sets to ride over each other. This successively lifts the pressure component (25) against the action of the spring (27) to move the clutch member (22) out of engagement with the conical surface (24) and then allows the spring (27) to move the pressure component (25) to a position where the clutch member (22) engages the conical surface (24).

Claims

1. An automatic one-way clutch means for use in an incrementing mechanism having a driving member rotatably and slidably mounted within a tubular body and arranged to advance an elongate element in one direction with respect to the tubular body within which the elongate element also is mounted, which one-way clutch means comprises a channel extending along the element, a generally conical surface formed internally on the driving member and surrounding the element, a blocking clutch member located in the channel and engageable with the conical surface, and freeing means adapted to disengage the clutch by lifting the clutch member out of engagement with the conical surface so as to disconnect the driving member from said element, which freeing means comprises a pressure component held against rotation with respect to the element and arranged to engage the clutch member, a spring acting on said component to urge the component away from its clutch disengaging position, and two sets of inter-engageable teeth formed respectively around the driving member and around the pressure component whereby rotation of the driving member with respect to the pressure component successively lifts said component against the action of the spring to move the clutch member out of engagement with the conical surface and allows the spring to move the pressure component to a position where the clutch member engages said surface, through the inter-action of the teeth riding over each other.

2. Clutch means as claimed in claim 1, wherein the generally conical surface is substantially, or wholly, continuous.

3. Clutch means as claimed in claim 1 or claim 2, wherein the pressure component is additionally configured to urge the clutch member to its active, conical surface engaging position.

4. Clutch means as claimed in claim 3, wherein the teeth respectively on the driving member and on the pressure component do not fully inter-engage when meshed, whereby the pressure component still exerts force on the clutch member when the teeth are meshed.

5. Clutch means as claimed in any of the preceding claims wherein there are two diametrically opposed similar clutch members, each acting between the conical surface and the elongate element.

6. Clutch means as claimed in any of the preceding claims wherein the or each clutch member comprises one of a ball, a roller, and a wedging member.

7. An incrementing mechanism comprising a tubular body, a driving member slidably and rotatably mounted within the tubular body, an elongate element slidably mounted within the driving member and one way clutch means as claimed in any of the preceding claims and arranged to effect coupling between the driving member and the elongate element when the driving member is moved in one direction with respect to the tubular body, and arranged not to drive the elongate element when the driving member is moved in the other direction with respect to the tubular body.

8. An injector device whenever incorporating an incrementing mechanism as claimed in claim 7, to effect incremental advance of the elongate element thereby to effect dispensing of a dose of medicament by virtue of inter-action between the elongate element and the piston of a medicament dispensing syringe or cartridge.

9. An injector device as claimed in claim 8, wherein there is a further one-way clutch mechanism arranged between the tubular body and the elongate element, to resist movement of the elongate element in said other direction.

10. An injector device as claimed in claim 9, wherein the further one-way clutch mechanism is selectively releasable to permit resetting of the incrementing mechanism to an initial position.

11. An injector device as claimed in claim 12, wherein the selective releasing of the further one-way clutch mechanism is performed automatically by disconnecting a syringe or cartridge from the injector mechanism.

12. An injector device as claimed in claim 8, wherein there is provided a non-resettable ratchet arrangement between the tubular body and the elongate element, whereby the injector device must be disposed of following full movement of the elongate element in a dose-dispensing direction.

13. An injector device as claimed in claim 12, wherein the ratchet arrangement comprises a spring blade bearing on the elongate element and deflected in the direction of advancement of the elongate element.

14. An injector device as claimed in any of claims 8 to 13, wherein there is a dose pre-setting arrangement which permits the pre-setting of a maximum dose to be dispensed less than the dose which otherwise could be pre-set on the mechanism.

15. An injector device as claimed in claim 14, wherein the dose pre-setting arrangement includes a pre-setting ring threadingly coupled to a pre-setting lock slidably mounted within the tubular body and with which the driving member engages on being moved to pre-set the dose.

16. An injector device as claimed in claim 15, wherein a locking arrangement is provided for the pre-setting ring.

17. An injector device as claimed in any of claims 8 to 16, wherein there is provided means to restrict the setting movement of the driving member to a dose not greater than the remaining dose within a syringe or cartridge connected to the device.

18. An injector device as claimed in claim 17, wherein said restricting means includes an abutment engageable with a stop at or adjacent the elongate element remote from a connected syringe or cartridge which abutment is rotatably coupled to the driving member.

19. An injector device as claimed in any of claims 8 to 18, wherein the driving member is provided with an end-cap by means of which the driving member is turned to move the driving member in the other direction and by means of which the driving member is depressed in the one direction.

20. An injector device as claimed in any of claims 8 to 18, wherein the driving member is coupled to an end-cap to permit the rotation of the driving member thereby to move the driving member in the other direction, the driving member being spring-urged to move in the one direction and being provided with a releasable catch to hold the driving member against movement in the one direction, until released.