公开(公告)号：US5971713A

公开(公告)日：1999-10-26

申请号：US222057

申请日：1998-12-29

Applicant: Howard L. North, Jr.

Inventor： Howard L. North, Jr.

IPC: F04B11/00 ,  F04B49/16 ,  G01N15/14 ,  F04B49/06

CPC classification number: F04B11/0033 ,  F04B49/16 ,  F04B2201/0808 ,  F04B2203/0201 ,  G01N15/1404

Abstract: A liquid supply system including a diaphragm pump, a novel liquid accumulator providing exceptionally high volume compliance, and a control of accumulator volume within narrow limits by continuous control of the pump motor. The accumulator achieves high volume compliance by arranging the kinematics of a main spring loading the accumulator to have a negative spring rate equal to the sum of all other positive spring rates produced by a second spring used to adjust the accumulator pressure, by the diaphragm, and by a pivot for a sensor lever. This lever moves with the diaphragm to actuate an optical sensor producing an signal indicative of small changes in liquid volume in the accumulator. This signal continuously modulates the power to the motor driving the pump so as to maintain the accumulator volume lose to a datum valve. This close control of liquid volume in a high compliance accumulator provides substantially pulse-free constant pressure liquid delivery from a pulsatile pump. The second spring may be adjusted to modify this constant pressure without disturbing the balance between positive and negative spring rates. Adjustment may be automatic in response to a variable such as liquid temperature whereby liquid pressure is automatically increased with lower liquid temperature to maintain liquid flow substantially constant through a flow cytometry apparatus used for particle analysis.

Abstract translation: 一种液体供应系统，包括隔膜泵，具有特别高体积顺应性的新型液体蓄能器，以及通过连续控制泵马达来控制在狭窄范围内的蓄能器体积。 蓄能器通过布置负载蓄能器的主弹簧的运动学来实现高体积顺应性，使得负弹簧速率等于由用于通过隔膜调节蓄能器压力的第二弹簧产生的所有其它正弹簧刚度的总和，以及 通过传感器杆的枢轴。 该杠杆随隔膜移动以致动光学传感器，产生指示蓄液器中液体体积变化小的信号。 该信号连续调节驱动泵的电机的功率，以保持蓄能器的体积损失到基准阀。 在高顺应性蓄能器中对液体体积的这种紧密控制提供了来自脉动泵的基本上无脉冲的恒定压力的液体输送。 可以调节第二弹簧以改变该恒定压力，而不会妨碍正和负弹簧速率之间的平衡。 响应于诸如液体温度的变量，调节可以是自动的，由此随着液体温度的降低，液体压力自动增加，以通过用于粒子分析的流式细胞仪来维持液体流动基本恒定。