Infusion pump with self-protection function and self-checking resetting method thereof

Abstract

The invention discloses an infusion pump with a self-protection function. The infusion pump includes a pump body assembly, and the pump body assembly includes a pump body, a piston rod, two optoelectronic switches, an optoelectronic switch separation blade and a controller. The piston rod is arranged in the pump body and connected with a driving motor through a transmission mechanism, and the driving motor can drive the piston rod to move back and forth in a linear mode in the pump body. The two optoelectronic switches are installed on the pump body at certain spacing, and the optoelectronic switch separation blade is fixed to the piston rod; when the optoelectronic separation blade moves to the optoelectronic switches, the optoelectronic switches can be shielded. The controller is electrically connected with the optoelectronic switches and the driving motor, and the controller controls running of the driving motor according to state signals output by the optoelectronic switches. The infusion pump can prevent exceptional mechanical collision caused when the piston rod is reset and after errors are accumulated. The invention further provides a self-checking resetting method capableof improving the resetting position accuracy of the piston rod.

Description

technical field [0001] The invention relates to an infusion pump for a liquid chromatograph, in particular to an infusion pump with a self-protection function and a self-checking and resetting method thereof. Background technique [0002] The infusion pump is a key component of the liquid chromatograph. Its main function is to output a high-pressure, stable and continuous mobile phase by overcoming the resistance of the chromatographic column, sending the sample to the chromatographic column for separation, and continuing to push the separated sample. Enter the detector for qualitative and quantitative analysis of the sample. The infusion pump in the liquid chromatograph is generally a reciprocating plunger pump, and the reciprocating plunger pump is composed of a plunger, a sealing ring, a pump head assembly, a driving mechanism, and a one-way valve. The outer ring of the sealing ring matches the cavity of the pump head assembly, one end of the plunger passes through the i...

AI Technical Summary

Problems solved by technology

[0005] The encoder feedback of this type of reciprocating plunger pump can detect whether the pump motor has lost steps during operation, but there is no relevant signal feedback at the starting point and end point of the reciprocating stroke of the plunger rod. Therefore, this type The reciprocating mechanism will inevitably have mechanical collisions when it is reset, and the position accuracy achieved by relying on mechanical limit to reset is low, and the reciprocating plunger pump must have high displacement repeatability to output accurate displacement curves. Therefore a high positional accuracy is required

[0006] In addition, if an error occurs during the movement, or the reciprocating piston rod peristalsis, the high-speed piston rod or plunger rod is likely to collide with the pump body, thereby damaging the parts and precision of the pump body

So far, there is no dual-motor-driven reciprocating plunger infusion pump with a perfect self-protection device

Images