Micro Pump without use of check valves to achieve no pulsation flow 株式会社フロム　渋谷大介、大野洋平、舟越省司、○南部浩章、関口陽子 Micro Pump without use of check valves to achieve no pulsation flow Authors: Satoshi Nakamura, Takafumi Shimizu and Ken Kitamura, FLOM Corporation Introduction Methodology Result and Discussion 1. Name of Component Parts Specifications Current pump plungers are designed to operate continuously in high pressure and high performance environments including analytical applications in chemical synthesis, reaction chemistry and HPLC. Controlled and precise flow can be affected by check valve design and performance. Product Name Linear Drive Pump with Switching Valve Left : Right : Pressure Sensor for Primary Pump Pressure Sensor for Secondary Pump / Outlet Port Maximum Pressure 350 bar (5075 psi) as expected Outlet port Flow Rate Range 1 uL ~ 1000 uL/ Min. Left : Right : Primary Pump Head Secondary Pump Head Flow Accuracy ±0.3 % Pump Driving Method Linear Drive Plunger stroke 10 mm 4-port Switching Valve / Inlet port (Substitute Using Check Valves) Pump + Valve Pump Uncertainty of check valve is now resolved with using switching valve! Valve Inlet port Pressure Accuracy < 5 % Direction of flow Features Flow Volume Calibration, Upper/ Lower Pressure Limiter 2. Principle of Operation Wetted Materials Stainless Steel (SUS 316), Sapphire, Ruby, PTFE, PCTFE, Teflon Elastomer, High-density Polyethylene Description of procedure Direction of Plunger Motion Primary Pump Head Secondary Pump Head ① Suction Position of Switching Valve Direction of Plunger Motion Direction of Plunger Motion Remote Control Input: Pump On/ Off, Output: Error Signal Communication RS232C Dimensions 130 (H) x 160 (W) x 280 (D) mm Weight Approximately 7 Kg ② Compression Position of Switching Valve Direction of Plunger Motion Direction of Plunger Motion Advantages Check valve malfunction has been eliminated No flow fluctuation Reduced maintenance Flow rate selectable in 1 uL/min. Can be used with high density solvents ③ Discharge Position of Switching Valve Direction of Plunger Motion Direction of Plunger Motion Pressure (=Flow Volume) Primary Pump Head Secondary Pump Head In this report, we describe the development of a micro flow pump with a target flow rate range less than 1.0mL/min. With applying an ultra high durability switching valve which passes 1,000,000 cycles in 2-position switching operation and linear drive pump which has 10mm long plunger stroke with real time pressure monitoring function. The result has been the elimination of the backlash and flow fluctuation contributed by the check valve. This new pump, which has a flow rate increment of 1.0 uL/min, is recommended for analysts who require the ultimate in precision with virtually no pump pulsations. Daily display of prototype at FLOM Corporation (Booth #5153) Solvent: Water Flow Rate: 200 uL/min. Pressure: 90 bar (1300 psi) Solvent: Water Flow Rate: 500 uL/min. Pressure: 165 bar (2390 psi) FLOM Corporation. http://www.flom.co.jp/ 5-32-10 Shinmachi, Ome, Tokyo 198-0024 Japan