Liquid chromatography high-pressure parallel cam pump

Abstract

The invention discloses a liquid chromatography high-pressure parallel cam pump, which comprises a motor, a pump main body, a cleaning block, a cam shaft, two cylindrical cams, two pump heads and two sets of reciprocating liquid delivering mechanisms, wherein each set of the reciprocating liquid delivering mechanisms comprises a plunger push rod, a plunger backseat, a plunger and a roller wheel; the pump heads are provided with pump chambers, liquid inlet holes and drain holes; one end of the plunger extends into the pump chambers of the pump heads; a sealing ring is arranged between the pumpheads and the plunger; a compression spring is sleeved outside the plunger; the back end of the compression spring presses against a shaft shoulder of the plunger backseat; N groups of cam curves areuniformly formed on the outer circumference of the cylindrical cams, N is an integer more than or equal to 2, and each group of the cam curves comprises ascending curves and descending curves; and the degree of the phase difference of the two cylindrical cams is 180 / N. Compared with the prior art, for the liquid chromatography high-pressure parallel cam pump, under the condition that the motor rotating speed, the delivery capacity per revolution of the pump and the diameter of the plunger are the same, the to-and-fro movement frequency of the plunger is improved by N times, and the pressure fluctuation of the liquid chromatography high-pressure parallel cam pump in work is reduced.

Description

technical field [0001] The invention relates to a liquid chromatography high-pressure parallel cam pump for a liquid chromatography instrument. Background technique [0002] Existing high-pressure parallel cam pumps for liquid chromatography, such as figure 1 As shown, it includes: a motor, a pump main body 10, two cleaning blocks 22 with a liquid inlet and a liquid outlet, a camshaft 9 connected to the motor, two identically shaped and positioned 180° fixedly connected to the camshaft Cylindrical cam 1, two pump heads 2 fixedly connected with pump main body 10, each cylindrical cam is connected with a pump head 2 through a set of reciprocating liquid delivery mechanism; each set of reciprocating liquid delivery mechanism includes plunger push rod 3, column Plug back seat 16 and plunger 4 connected to one end of plunger push rod, one end of plunger push rod 3 is provided with roller 5; pump head 2 has pump chamber 11 and inlet hole 6 and discharge liquid connected with pump...

AI Technical Summary

Problems solved by technology

Regardless of whether the plunger deviates from the origin or returns to the origin, the whereabouts and source of the radial force are the sealing ring, and the sealing ring is bearing the extra radial force brought by the plunger, which is reducing the normal force of the sealing ring. service life

[0005] Obviously, a pump with large pressure fluctuations and poorly controlled plunger movement trajectory cannot bring stable flow and high detection accuracy to the detection system.

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