| 摘要 |
The present invention provides for an injection device including a syringe with a proximal end, a distal end, a needle extending from the distal end, and a plunger inserted into the proximal end. A guard is slidable on the syringe, has a proximal end, a distal end, and is biased from a first position wherein the needle is exposed towards a second position wherein the guard covers the needle. The injection device includes first and second sets of cooperating detents for retaining the guard and syringe in the first and second positions, respectively. A latch member extends proximally from the guard that is engageable by the plunger as the plunger is depressed to release the first set of cooperating detents. Upon release, a spring element biases the guard towards the second position until the second set of cooperating detents engage and secure the guard in the second position. |
| 主权项 |
1. A method for delivering a therapeutic agent using an injection device including a guard comprising a proximal end, a distal end, and a latch member extending from the guard, and a syringe slidably received in the guard, the syringe comprising a proximal end, a distal end, a needle extending from the distal end, and a plunger extending from the proximal end, the syringe being biased to move relative to the guard from a first position wherein the needle is exposed beyond the distal end of the guard towards a second position wherein the needle is disposed within the guard, the latch member retaining the guard in the first position, the method comprising:
inserting the needle into a patient; depressing the plunger to inject the therapeutic agent into the patient until the plunger engages the latch member; depressing the plunger further to disengage the latch member, whereupon the syringe is free to move from the first position; depressing the plunger yet further to complete injection of the therapeutic agent into the patient; and releasing the plunger, whereupon the syringe automatically withdraws proximally within the guard towards the second position until cooperating detents on the guard and the syringe engage one another to prevent subsequent movement of the syringe with respect to the guard in both the distal and proximal directions. |
