Pen-type injector
The present invention relates to injectors, such as pen-type injectors, that provide for administration of medicinal products from a multidose-cartridge and permit a user to set the delivery dose. The injector may include a housing, a piston rod adapted to operate through the housing, a dose dial sleeve located between the housing and the piston rod, and a drive sleeve located between the dose dial sleeve and the piston rod. The dose dial sleeve may have a helical thread of first lead and the drive sleeve may have a helical groove of second lead. The first lead of the helical thread and the second lead of the helical groove may be the same.
1. A pen type injector comprising:
a housing;
a piston rod adapted to operate through the housing;
a clicker configured to generate audible feedback, the clicker comprising a first sleeve, the first sleeve comprising a flexible arm;
a second sleeve;
a dose dial grip; and
a nut configured to be advanced along a thread towards a radial stop when the dose dial grip is rotated to dial a dose, such that when a final dose position is reached, the nut abuts the radial stop,
wherein an end of the clicker comprises a plurality of circumferential teeth adapted to be coupled to a corresponding plurality of circumferential teeth of the second sleeve and adapted to prevent relative rotation between the first and second sleeves in a first rotational direction when the circumferential teeth of the first sleeve and the circumferential teeth of the second sleeve are coupled, and the clicker and the second sleeve are configured to rotate with the dose dial grip in the first rotational direction when the circumferential teeth of the first sleeve and the circumferential teeth of the second sleeve are coupled.
2. The pen type injector according to claim 1 , wherein the second sleeve is a clutch.
3. The pen type injector according to claim 1 , wherein the clicker is generally cylindrical.
4. The pen type injector according to claim 1 , wherein a free end of the arm has a toothed member.
5. The pen type injector according to claim 1 , wherein the clicker is disposed between the second sleeve and a splined surface of the housing.
6. The pen type injector according to claim 1 , wherein the flexible arm is configured to ride over splines of a splined surface of the pen type injector to generate audible feedback when the clicker and the splined surface are rotated relative to each other.
7. The pen type injector according to claim 1 , wherein the nut is a half-nut.
8. The pen type injector according to claim 1 , wherein the housing comprises a housing body and an insert secured against longitudinal or rotational motion relative to the housing body.
9. The pen type injector according to claim 8 , wherein the insert is integral with the housing body.
10. The pen type injector according to claim 1 , wherein the piston rod has a first end comprising a threaded portion.
11. The pen type injector according to claim 1 , further comprising a cartridge disposed within the housing, the cartridge containing a medicament.
12. The pen type injector according to claim 1 , wherein the circumferential teeth of the first and second sleeves are adapted to prevent relative rotation between the first and second sleeves in the first rotational direction and to permit relative rotation between the first and second sleeves in a second rotational direction when the circumferential teeth of the first sleeve and the circumferential teeth of the second sleeve are coupled.
13. The pen type injector according to claim 1 , wherein the nut is configured to move axially relative to the housing without rotating relative to the housing when the dose dial grip is rotated to dial the dose.
14. The pen type injector according to claim 1 , wherein the radial stop is separate from the thread.
15. The pen type injector according to claim 1 , wherein the nut is a partial nut that spans less than an entire circle and is the only partial nut within the housing.
16. The pen type injector according to claim 1 , wherein the nut comprises an internal thread.
17. A pen type injector comprising:
a housing;
a piston rod disposed at least partially within the housing, the piston rod being moveable relative to the housing;
a first sleeve disposed at least partially within the housing, the first sleeve comprising a flexible arm, an end of the first sleeve comprising circumferentially spaced teeth;
a second sleeve disposed at least partially within the housing, the second sleeve comprising circumferentially spaced teeth configured to be coupled to the teeth of the first sleeve to prevent relative rotation between the first and second sleeves in a first rotational direction;
a splined surface comprising a plurality of splines, wherein the flexible arm of the first sleeve is configured to ride over the splines to generate audible feedback when the first sleeve and the splined surface are rotated relative to each other;
a dose dial grip; and
a nut configured to be advanced along a thread towards a radial stop when the dose dial grip is rotated to dial a dose, such that when a final dose position is reached, the nut abuts the radial stop.
18. The pen type injector according to claim 17 , wherein the circumferentially spaced teeth of the first and second sleeves extend axially.
19. The pen type injector according to claim 17 , wherein a free end of the flexible arm has a toothed member.
20. The pen type injector according to claim 17 , wherein the second sleeve is a clutch.
21. The pen type injector according to claim 17 , wherein the first and second sleeves are configured to rotate with the dose dial grip in the first rotational direction when the teeth of the first sleeve and the teeth of the second sleeve are coupled.
22. The pen type injector according to claim 17 , wherein the circumferentially spaced teeth of the first and second sleeves are adapted to prevent relative rotation between the first and second sleeves in the first rotational direction and to permit relative rotation between the first and second sleeves in a second rotational direction when the circumferentially spaced teeth of the first sleeve and the circumferentially spaced teeth of the second sleeve are coupled.
23. The pen type injector according to claim 17 , wherein the nut is configured to move axially relative to the housing without rotating relative to the housing when the dose dial grip is rotated to dial the dose.
24. The pen type injector according to claim 17 , wherein the radial stop is separate from the thread.
25. The pen type injector according to claim 17 , wherein the nut is a partial nut that spans less than an entire circle and is the only partial nut within the housing.
26. The pen type injector according to claim 17 , wherein the nut comprises an internal thread.
27. A pen type injector comprising:
a housing;
a piston rod disposed at least partially within the housing, the piston rod being moveable relative to the housing;
a first sleeve disposed at least partially within the housing, the first sleeve comprising a flexible arm;
a second sleeve configured to engage the first sleeve in a manner to prevent relative rotation between the first and second sleeves in a first rotational direction;
a splined surface comprising a plurality of splines, wherein the flexible arm of the first sleeve is configured to ride over the splines to generate audible feedback when the first sleeve and the splined surface are rotated relative to each other;
a dose dial grip; and
a nut configured to be advanced along a thread towards a radial stop when the dose dial grip is rotated to dial a dose, such that when a final dose position is reached, the nut abuts the radial stop.
28. The pen type injector according to claim 27 , wherein the first sleeve comprises circumferentially spaced teeth configured to be coupled to circumferentially spaced teeth of the first sleeve to prevent relative rotation between the first and second sleeves in the first rotational direction.
29. The pen type injector according to claim 28 , wherein the circumferentially spaced teeth of the first and second sleeves extend axially.
30. The pen type injector according to claim 28 , wherein the circumferentially spaced teeth of the first and second sleeves are adapted to prevent relative rotation between the first and second sleeves in the first rotational direction and to permit relative rotation between the first and second sleeves in a second rotational direction when the circumferentially spaced teeth of the first sleeve and the circumferentially spaced teeth of the second sleeve are coupled.
31. The pen type injector according to claim 27 , wherein a free end of the flexible arm has a toothed member.
32. The pen type injector according to claim 27 , wherein the second sleeve is a clutch.
33. The pen type injector according to claim 27 , wherein the first and second sleeves are configured to rotate with the dose dial grip when the first sleeve and the second sleeve are coupled.
34. The pen type injector according to claim 27 , wherein the nut is configured to move axially relative to the housing without rotating relative to the housing when the dose dial grip is rotated to dial the dose.
35. The pen type injector according to claim 27 , wherein the radial stop is separate from the thread.
36. The pen type injector according to claim 27 , wherein the nut is a partial nut that spans less than an entire circle and is the only partial nut within the housing.
37. The pen type injector according to claim 27 , wherein the nut comprises an internal thread.