Claims
- 1. A device for delivering fluid to a patient, comprising:
a. a reservoir including a side wall extending towards an outlet; b. a plunger received in the reservoir; c. a threaded lead screw coupled to the plunger; d. a dispenser including a linear actuator and a transmission that couples the linear actuator to the lead screw and enables the linear actuator to rotate the lead screw, the transmission including,
i. a frictional engagement surface coupled to the lead screw such that the frictional engagement surface is immovable relative to the lead screw; ii. engagement means for selectively engaging the frictional engagement surface such that the engagement means engages the frictional engagement surface when the engagement means is moved in a first direction, but does not engage the frictional engagement surface when the engagement means is moved in a second direction.
- 2. The device of claim 1, wherein the frictional engagement surface is a gear mounted coaxially with the lead screw.
- 3. The device of claim 2, wherein the gear has teeth extending formed on a face thereof.
- 4. The device of claim 3, wherein the engagement means comprises a substantially planar member mounted coaxially with the lead screw and adjacent to the teeth of the gear, the planar member having a flexible projecting member that projects towards the teeth, such that the projecting member engages the teeth when the planar member is rotated in a first direction and the projecting member does not engage the teeth when the planar member is rotated in a second direction.
- 5. The device of claim 2, wherein the teeth are formed on an outer circumferential edge of the gear.
- 6. The device of claim 5, wherein the engagement means is a cam mounted for linear movement substantially parallel to the axis of the gear and the cam includes a cam surface that is shaped and arranged such that, when the cam is moved from the first position to the second position, the cam surface engages a tooth and causes the gear to rotate.
- 7. The device of claim 5, wherein the engagement means is a hook mounted for linear movement substantially perpendicular to the axis of the gear and the hook is shaped and arranged such that, when the hook is moved from the first position to the second position, the hook engages a tooth and causes the gear to rotate.
- 8. The device of claim 1, wherein the linear actuator includes a shape memory element.
- 9. The device of claim 1, wherein the linear actuator includes a return element.
- 10. The device of claim 9, wherein the return element comprises a wound clock spring.
- 11. The device of claim 9, wherein the return element is a helical compression spring.
- 12. The device of claim 9, wherein the return element is a helical tension spring.
- 13. The device of claim 4, wherein the substantially planar member of the engagement means is formed from a single piece of material.
- 14. The device of claim 13, wherein the substantially planar member of the engagement means is formed from a single piece of metal.
- 15. The device of claim 1, wherein the second direction is opposite the first direction.
- 16. The device of claim 1, wherein the linear actuator includes a return element and a shape memory element, and wherein a changeable length of the shape memory element decreasing from an uncharged length to a charged length resets the return element.
- 17. A device for delivering fluid to a patient, comprising:
a. a reservoir including a side wall extending towards an outlet; b. a plunger received in the reservoir; c. an assembly comprising a threaded lead screw coupled to the plunger and a nut threaded onto the lead screw and mounted in a fixed position relative to the lead screw such that rotation of the nut moves the lead screw through the nut; d. a dispenser including a linear actuator and a transmission that couples the linear actuator to the nut and enables the linear actuator to rotate the nut, the transmission including,
i. a frictional engagement surface coupled to the nut such that the frictional engagement surface is immovable relative to the nut; ii. engagement means for selectively engaging the frictional engagement surface such that the engagement means engages the frictional engagement surface when the engagement means is moved in a first direction, but does not engage the frictional engagement surface when the engagement means is moved in a second direction.
- 18. The device of claim 17, wherein the frictional engagement surface is a surface of the nut.
- 19. The device of claim 18, wherein the frictional engagement surface is a gear having teeth formed in the nut.
- 20. The device of claim 19, wherein the teeth of the gear are formed on a side of the nut.
- 21. The device of claim 20, wherein the engagement means comprises a substantially planar member mounted coaxially with the lead screw and adjacent to the teeth of the gear, the planar member having a flexible projecting member that projects towards the teeth, such that the projecting member engages the teeth when the planar member is rotated in a first direction and the projecting member does not engage the teeth when the planar member is rotated in a second direction.
- 22. The device of claim 19, wherein the teeth are formed on an outer circumferential edge of the gear.
- 23. The device of claim 22, wherein the engagement means is a cam mounted for linear movement substantially parallel to the axis of the gear and the cam includes a cam surface that is shaped and arranged such that, when the cam is moved from the first position to the second position, the cam surface engages a tooth and causes the gear to rotate.
- 24. The device of claim 19, wherein the engagement means is a hook mounted for linear movement substantially perpendicular to the axis of the gear and the hook is shaped and arranged such that, when the hook is moved from the first position to the second position, the hook engages a tooth and causes the gear to rotate.
- 25. The device of claim 17, wherein the linear actuator includes a shape memory element.
- 26. The device of claim 17, wherein the linear actuator includes a return element.
- 27. The device of claim 26, wherein the return element comprises a wound clock spring.
- 28. The device of claim 26, wherein the return element is a helical compression spring.
- 29. The device of claim 26, wherein the return element is a helical tension spring.
- 30. The device of claim 21, wherein the substantially planar member of the engagement means is formed from a single piece of material.
- 31. The device of claim 30, wherein the substantially planar member of the engagement means is formed from a single piece of metal.
- 32. The device of claim 17, wherein the second direction is opposite the first direction.
- 33. The device of claim 17, wherein the linear actuator includes a return element and a shape memory element, and wherein a changeable length of the shape memory element decreasing from an uncharged length to a charged length resets the return element.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation-in-part of co-pending U.S. patent application Ser. No. 10/128,205 (Atty. Docket No. INSL-122), which was filed on Apr. 23, 2002, is entitled DISPENSER FOR PATIENT INFUSION DEVICE, is assigned to the assignee of the present application and is incorporated herein by reference.
[0002] The present application is related to co-pending U.S. patent application Ser. No. 10/128,203 (Atty. Docket No. INSL-123), which was filed on Apr. 23, 2002, is entitled DISPENSER FOR PATIENT INFUSION DEVICE, is assigned to the assignee of the present application and is incorporated herein by reference.
[0003] The present application is related to co-pending U.S. patent application Ser. No. 09/943,992 (Atty. Docket No. INSL-110), which was filed on Aug. 31, 2001, is entitled DEVICES, SYSTEMS AND METHODS FOR PATIENT INFUSION, is assigned to the assignee of the present application and is incorporated herein by reference.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
10128205 |
Apr 2002 |
US |
Child |
10704291 |
Nov 2003 |
US |