Patent attributes
The present disclosure provides better aspiration and dispensing by a common innovative mechanism by (i) offsetting the diameter of a bottom piston (tube) with a slightly narrower top piston (rod) when the two are swept together by O-rings to give extremely fine resolution, thereby eliminating the need for any filamentous piston and sealing means, (ii) letting the bottom tube be swept alone without offset to give high flow (iii) using a tapered top rod with thick-walled compliant O-ring seals to increase the resolution multiplier another order or magnitude, (iv) an at-the-ready interpiston space for contact-free blowoff, including viscous samples, (v) dead space filler mandrels and an integrated small valve to reduce or eliminate interpiston and disposable tip space prior to aspiration, and (vi) a mechanism for storing energy during disposable tip pickup to shoot dispensed samples contact-free down into long tubes.
