Infusion pump for liquid chromatograph

Abstract

The invention discloses an infusion pump for a liquid chromatograph. The infusion pump for the liquid chromatograph comprises a pump body, nut screw rod drive components, a bearing and positioning anti-backlash screws. The pump body is provided with a bearing mounting hole, and an axial elastic retaining ring is mounted on the rear end of the bearing mounting hole. The nut screw rod drive componenets are located in the pump body and include a screw rod and a nut. The bearing comprises an inner bearing ring and an outer bearing ring, and the inner bearing ring is fixed on the rear end of the screw rod. The bearing outer ring is embedded in the bearing mounting hole, and the rear end face of the outer bearing ring abuts against the axial elastic retaining ring. The positioning anti-backlashscrews are connected on the pump body along the radial direction of the bearing. The end, facing the bearing, of the positioning anti-backlash screws includes a tapered surface. The positioning anti-backlash screws are arranged along the circumferential direction of the bearing. The edge of the front end of the outer bearing ring abuts against the tapered surface of the anti-backlash screws. The infusion pump for the liquid chromatograph can eliminate the axial backlash caused by the installation of the bearing and improve the displacement precision and pressure stability of the output of theinfusion pump.

Description

technical field [0001] The invention relates to a liquid chromatograph, in particular to an infusion pump for the liquid chromatograph. Background technique [0002] A liquid chromatograph generally consists of a high-pressure infusion pump, a liquid storage bottle, a sample injector, a chromatographic column, a detector, a waste liquid tank, and a data recording and processing device. One end of the high-pressure infusion pump is connected to the liquid storage bottle through a catheter, the other end is connected to the inlet of the sampler through a catheter, the outlet of the sampler is connected to the inlet of the chromatographic column through a catheter, and the outlet of the chromatographic column is connected to the detector through a catheter. The device is connected with the data recording and processing device through the data line. The working principle of the liquid chromatograph is: the mobile phase is installed in the liquid storage bottle, and the mobile p...

AI Technical Summary

Problems solved by technology

This method of fixing the bearing has the following problems: relying on the elastic circlip for the hole and the step of the stepped hole on the pump body to limit the position, there will be an axial gap, because the installation of the elastic circlip for the hole requires axial clearance, otherwise it cannot be installed. This means that there will be a slight axial movement between the screw rod and the bearing. This kind of movement will not only affect the output precision of the piston rod, but also increase the noise of the pump body, which is not conducive to the precision of the pump body. ;In addition, the installation of the circlip for the hole is difficult due to the narrow axial space

[0005] In order to output stable pressure, the infusion pump in liquid chromatography must have a precise pump body structure as the foundation to output accurate displacement, and the infusion pump needs to frequently perform high-speed reciprocating motion, and the motor frequently performs forward and reverse switching and variable speed operation. A small axial gap is enough to make the output displacement accuracy worse, and it will increase vibration and noise when running at high speed, making the working condition of the mechanism worse

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