摘要 |
A rotational pressure drive for filling a medical syringe with a fluid and obtaining, maintaining, and releasing a desired fluid pressure within the syringe. The commercially available medical syringe includes a barrel with a plunger extending therein. Extending laterally and radially about the proximal end of the syringe barrel are several flanges. The rotational pressure drive comprises a hollow cylindrical chamber with a partially closed, proximal end with an opening therethrough. The drive further includes an axial extension member extending through the opening in the partially closed end for engaging and urging the proximal end of the syringe plunger toward the partially closed, proximal end. The drive, in another aspect, includes a syringe plunger having a distal and a proximal portion. The distal portion is inserted into the syringe barrel with the proximal portion extending through the opening of the partially closed, proximal portion of the drive. Positioned circumferentially and longitudinally along the chamber are pluralities of internal threads with individual starts for engaging the radially extending flanges of the syringe barrel. The plunger or axial extension member of the drive is pulled toward the partially closed, proximal end of the drive to fill the syringe with fluid. The flanges of the syringe barrel are rotationally engaged with the starts of the internal thread pluralities for advancement into the passageway of the drive. As the hollow chamber of the pressure drive is rotated with respect to the syringe barrel, the plunger is pushed into the syringe barrel to obtain and maintain a desired fluid pressure therein.
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