Dosage unit for dosing a number of measured quantities of a liquid, such as an insulin preparation, from a container, preferably a cartridge
First Claim
1. A dosage unit for dosing a number of measured quantities of a liquid, such as an insulin preparation, from a container, preferably a separate cartridge, said dosage unit comprising a cylindrical casing for the container, the distal end of the casing being provided with means for fastening a double-pointed injection needle, one point thereof being provided to pierce a membrane closing one end of the container, and said dosage unit comprising a piston rod for exerting a force on a piston closing the other end of the container, and an adjustment means provided with an internal thread, said adjustment means being in rotatable engagement with an external thread on the casing and adapted to adjust the length of the stroke of the piston rod according to the dosage needed in each case, the dosage being adjusted to be readable on a scale located on the dosage unit, characterised in that the dosage unit is provided with a first ratchet means (17) between the casing (1) and the piston rod (13), said ratchet means allowing the displacement of the piston rod (13) in a direction towards the distal end of the casing and preventing the displacement in the opposite direction, and with a second ratchet means (32) between the adjustment means (20) and the casing (1) or a second part of the dosage unit, which is unturnable in relation to the casing, and in relation to which the adjustment means is rotatable, said second ratchet means allowing the rotation of the adjustment means (20) in a direction forward towards the distal end of the casing (1) and preventing the rotation in the opposite direction.
2 Assignments
0 Petitions
Accused Products
Abstract
A dosage unit for dosing a number of measured quantities of a liquid, such as insulin, from a cartridge (2), said dosage unit comprising a cylindrical casing (1) for the cartridge (2), the distal end of the casing (1) being provided with means for fastening an injection needle (5) with two points protruding at opposite sides, one point (7) thereof being provided to be plunged into the cartridge (2). The other end of the casing comprises a piston rod (13) for exerting a force on a piston (8) inside the cartridge (2) and an adjustment means (20) provided with an inner thread (21), said adjustment means being in rotatable engagement with an outer thread (19) on the outside of the casing (1). The adjustment means (20) is adapted to limit the length of the stroke of the piston rod (13) after adjustment in accordance with a measuring scale (37, 38) stating the desired dosage quantity. This dosage unit enables an easy and precise adjustment of the desired quantity and ensures that the dosage unit cannot be used again inadvertently, when the cartridge is empty.
152 Citations
14 Claims
- 1. A dosage unit for dosing a number of measured quantities of a liquid, such as an insulin preparation, from a container, preferably a separate cartridge, said dosage unit comprising a cylindrical casing for the container, the distal end of the casing being provided with means for fastening a double-pointed injection needle, one point thereof being provided to pierce a membrane closing one end of the container, and said dosage unit comprising a piston rod for exerting a force on a piston closing the other end of the container, and an adjustment means provided with an internal thread, said adjustment means being in rotatable engagement with an external thread on the casing and adapted to adjust the length of the stroke of the piston rod according to the dosage needed in each case, the dosage being adjusted to be readable on a scale located on the dosage unit, characterised in that the dosage unit is provided with a first ratchet means (17) between the casing (1) and the piston rod (13), said ratchet means allowing the displacement of the piston rod (13) in a direction towards the distal end of the casing and preventing the displacement in the opposite direction, and with a second ratchet means (32) between the adjustment means (20) and the casing (1) or a second part of the dosage unit, which is unturnable in relation to the casing, and in relation to which the adjustment means is rotatable, said second ratchet means allowing the rotation of the adjustment means (20) in a direction forward towards the distal end of the casing (1) and preventing the rotation in the opposite direction.
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14. A dosage unit for dosing a number of measured quantities of a liquid, such as an insulin preparation, from a container, preferably a separate cartridge, said dosage unit comprising a cylindrical casing for the container, the distal end of the casing being provided with means for fastening a double-pointed injection needle, one point thereof being provided to pierce a membrane closing one end of the container, and said dosage unit comprising a piston rod for exerting a force on a piston closing the other end of the container, and an adjustment means provided with an internal thread, said adjustment means being in rotatable engagement with an external thread on the casing and adapted to adjust the length of the stroke of the piston rod according to the dosage needed in each case, the dosage being adjusted to be readable on a scale located on the dosage unit, characterised in that the dosage unit is provided with a first ratchet means (17) between the casing (1) and the piston rod (13), said ratchet means allowing the displacement of the piston rod (13) in a direction towards the distal end of the casing and preventing the displacement in the opposite direction, and with a second ratchet means (32) between the adjustment means (20) and the casing (1) or a second part of the dosage unit, which is unturnable in relation to the casing, and in relation to which the adjustment means is rotatable, said second ratchet means allowing the rotation of the adjustment means (20) in a direction forward towards the distal end of the casing (1) and preventing the rotation in the opposite direction, the ratchet means (17, 32) being adapted in such a way that the effect of the movement-impeding parts can temporarily be overcome by exerting a stronger force.
Specification