US 5,238,654 A · Syringe drive with lead screw mechanism

Abstract

A syringe of relatively simple construction which is capable of both accurate and reproducible sample volume withdrawals, including volumes of 1.0 .mu.l or less, is provided. The syringe drive mechanism is preferably adapted for use in a liquid sampling apparatus and includes a threaded lead screw, a drive for rotating the screw, and a syringe having a plunger for withdrawing a liquid sample. The plunger is mechanically connected to the rotating lead screw by a nut threaded onto the screw and a slider mechanism associated with the nut which also is secured to the plunger. The nut is designed so that lateral misalignment of the drive screw does not affect the precise linear movement of the slider mechanism, and consequently, the plunger. This provides a mechanism which is less expensive to assemble and align properly, but which has a high degree of accuracy and reproducibility.

Claims18

Dependent claims

A syringe drive with a lead screw mechanism for use in a sampling apparatus comprising:

a threaded lead screw;
means for rotating said lead screw;
a syringe having a plunger for withdrawing a liquid sample;
means for mechanically connecting said plunger to said lead screw, said connecting means comprising a traveling nut threaded onto said lead screw, a slider mechanism in which said nut is mounted and including means for securing said plunger thereto, means for aligning said slider mechanism for linear movement, and means for permitting lateral movement of said nut while threaded onto said lead screw relative to said slider means.

1 more element

Dependencies are inferred from the claim text.

Syringe drive with lead screw mechanism

Life of this patent

Syringe drive with lead screw mechanism

Life of this patent

Abstract

Claims18