Automatic Injector
First Claim
1. An automatic injector for delivering a dose of medicament into a user'"'"'s body at an injection site, comprising:
- a housing having a proximal end and a distal end;
a syringe assembly movably supported within the housing, the syringe assembly including a syringe barrel having an open end and a closed end, a plunger assembly including a stopper, and an injection needle;
a drive member operably and releasably coupled with the syringe barrel and movable between a retracted position and an extended position;
a drive spring operably coupled to the drive member to bias the drive member into the extended position;
a trigger mechanism including a latch capable of retaining the drive member in the retracted position against a force of the drive spring;
at least one mechanical stop connected to the housing, limiting movement of the syringe assembly toward the distal end of the housing to a maximally extended position;
wherein;
activation of the trigger mechanism causes movement of the latch to release the drive member retained in the retracted position, and the drive spring forces the drive member, and the syringe assembly releasably coupled thereto, to move toward the distal end of the housing from the retracted position toward the extended position, forcing the needle to puncture the user'"'"'s body at the injection site;
as the needle punctures the user'"'"'s body, a resistive force acts upon the needle, and upon one of the syringe barrel contacting the mechanical stop and resistive force reaching a predetermined level, the drive member disengages the syringe barrel and additional movement of the syringe barrel and the needle coupled thereto in the direction of the distal end of the housing is prevented; and
with the drive member disengaged from the syringe barrel, the drive spring forces continued movement of the drive member in the direction of the distal end of the housing, forcing the drive member into engagement with the syringe plunger assembly, and forcing the plunger assembly to expel the medicament contained within the syringe barrel through the needle into the user'"'"'s body.
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Accused Products
Abstract
An injector is automatic in that the needle insertion into the injection site (e.g., a patient'"'"'s skin) is triggered by the user or caregiver, the insertion is automatic, the following delivery is automatically initiated upon needle insertion, and the needle is shielded automatically after the end of delivery. Preferably the user does not see the needle prior to, during, or after injection. The injector includes a proximal and distal housings and a needle shield arranged to slide on the distal housing. The injector has a driver arranged to move the syringe to cause the needle penetration, to inject the drug, and subsequently to release the shield. The syringe needle is shielded and the shield locked automatically after delivery is completed. The patient does not experience any injector force on the tissue during injection. The injector has built in patient safety features.
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Citations
24 Claims
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1. An automatic injector for delivering a dose of medicament into a user'"'"'s body at an injection site, comprising:
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a housing having a proximal end and a distal end;
a syringe assembly movably supported within the housing, the syringe assembly including a syringe barrel having an open end and a closed end, a plunger assembly including a stopper, and an injection needle;
a drive member operably and releasably coupled with the syringe barrel and movable between a retracted position and an extended position;
a drive spring operably coupled to the drive member to bias the drive member into the extended position;
a trigger mechanism including a latch capable of retaining the drive member in the retracted position against a force of the drive spring;
at least one mechanical stop connected to the housing, limiting movement of the syringe assembly toward the distal end of the housing to a maximally extended position;
wherein;
activation of the trigger mechanism causes movement of the latch to release the drive member retained in the retracted position, and the drive spring forces the drive member, and the syringe assembly releasably coupled thereto, to move toward the distal end of the housing from the retracted position toward the extended position, forcing the needle to puncture the user'"'"'s body at the injection site;
as the needle punctures the user'"'"'s body, a resistive force acts upon the needle, and upon one of the syringe barrel contacting the mechanical stop and resistive force reaching a predetermined level, the drive member disengages the syringe barrel and additional movement of the syringe barrel and the needle coupled thereto in the direction of the distal end of the housing is prevented; and
with the drive member disengaged from the syringe barrel, the drive spring forces continued movement of the drive member in the direction of the distal end of the housing, forcing the drive member into engagement with the syringe plunger assembly, and forcing the plunger assembly to expel the medicament contained within the syringe barrel through the needle into the user'"'"'s body. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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14. An automatic injector for delivering a dose of medicament into a user'"'"'s body at an injection site, comprising:
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a housing having a proximal end and a distal end;
a syringe assembly movably supported within the housing, the syringe assembly including a syringe barrel adapted to contain the medicament, a plunger assembly, and an injection needle;
a drive member operably and releasably coupled with the syringe barrel and movable between a drive member retracted position and a drive member extended position;
a drive member drive spring operably coupled to the drive member to bias the drive member in the drive member extended position;
a trigger mechanism including a drive member latch capable of retaining the drive member in the drive member retracted position against the force of the drive member drive spring;
a shield operably and movably coupled to the distal end of the housing and movable between a shield retracted position and a shield extended position;
a shield drive spring operably coupled to the shield to bias the shield member into the shield extended position;
a first shield latch adapted to engage the shield and capable of retaining the shield in the shield retracted position against the force of the shield drive spring;
wherein activation of the trigger mechanism causes movement of the drive member latch to release the drive member retained in the drive member retracted position, and the drive member drive spring forces the drive member, and the syringe assembly releasably coupled thereto, to move toward the distal end of the enclosure from the drive member retracted position toward the drive member extended position, forcing the needle to puncture the user'"'"'s body at the injection site;
at a position intermediate the drive member retracted position and the drive member extended position, the drive member contacts the first shield latch to move the first shield latch to release the shield from the shield retracted position; and
the shield spring moves the shield from the shield retracted position to the shield extended position as the drive member drive spring moves the drive member from the drive member intermediate position to the drive member extended position. - View Dependent Claims (15, 16, 17, 18, 19, 20)
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21. An automatic injector for delivering a dose of medicament into a user at an injection site, comprising:
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a housing having a proximal end and a distal end;
a syringe assembly movably supported within the housing, the syringe assembly including a syringe barrel adapted to contain the medicament, a plunger assembly, and an injection needle;
a drive member operably and releasably coupled with the syringe barrel and movable between a drive member retracted position and a drive member extended position;
a drive member drive spring operably coupled to the drive member to bias the drive member in the drive member extended position;
a trigger mechanism including a drive member latch capable of retaining the drive member in the drive member retracted position against the force of the drive member drive spring;
a shield operably and movably coupled to the distal end of the housing and movable between a shield retracted position and a shield extended position;
a shield drive spring operably coupled to the shield to bias the shield member into the shield extended position;
a first shield latch adapted to engage the shield and capable of retaining the shield in the shield retracted position against the force of the shield drive spring;
at least one mechanical stop connected to the housing, limiting movement of the syringe assembly toward the distal end of the housing to a maximally extended position;
wherein;
activation of the trigger mechanism causes movement of the drive member latch to release the drive member retained in the drive member retracted position, and the drive member drive spring forces the drive member, and the syringe assembly releasably coupled thereto, to move toward the distal end of the enclosure from the drive member retracted position toward the drive member extended position, forcing the needle to puncture the user'"'"'s body at the injection site;
as the needle punctures the user'"'"'s body, a resistive force acts upon the needle, and upon one of the syringe barrel contacting the mechanical stop and resistive force reaching a predetermined level, the drive member disengages the syringe barrel and additional movement of the syringe barrel and the needle coupled thereto in the direction of the distal end of the housing is prevented;
with the drive member disengaged from the syringe barrel, the drive member drive spring forces continued movement of the drive member in the direction of the distal end of the housing, forcing the drive member into engagement with the syringe plunger assembly, and forcing the plunger assembly to expel the medicament contained within the syringe barrel through the needle into the user'"'"'s body until the drive member reaches the extended position;
at a position intermediate the drive member retracted position and the drive member extended position, the drive member contacts the first shield latch to move the first shield latch to release the shield from the shield retracted position; and
the shield spring moves the shield from the shield retracted position to the shield extended position as the drive member drive spring moves the drive member from the drive member intermediate position to the drive member extended position.
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22. A method of manufacturing an automatic injector for delivering a fluid, comprising the steps of:
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providing a cylindrical proximal housing assembly including a driver member, a driver spring, and a trigger mechanism having a latch, the driver member being retained in a retracted position by the latch;
providing a cylindrical distal housing assembly;
installing a syringe assembly within one of the proximal housing assembly and the distal housing assembly; and
connecting the distal housing assembly to the proximal housing assembly to form an enclosure at least substantially enclosing the syringe assembly such that the syringe assembly is operably engaged with the driver member. - View Dependent Claims (23, 24)
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Specification