| 摘要 |
A syringe and method for use which may be selectively operated between a freely reciprocating position and a restricted position. A triggering means configured with a trigger attached to the plunger of the syringe is employed. The triggering means includes threads located external of the plunger and corresponding threads internal of the barrel of the syringe. Upon actuation of the trigger, the threads on the plunger are retracted from their position of engagement with the threads on the barrel, thereby placing the syringe in position for free sliding movement of the plunger with respect to the barrel. The trigger is biased to the engaged position so that if the trigger is released, the threads on the plunger return to their position of engagement with the threads on the barrel. In the restricted position, the plunger may be screwed into or out of the barrel by rotating the plunger, enabling the operator of the syringe to maintain strict control over the amount of pressure in the syringe. The triggering means employs a plurality of ramp and channel configurations which are disposed at approximately the same angel as the threads on the plunger and barrel which direct the retraction of the threads on the plunger from engagement to disengagement with the threads on the barrel. |
