Adjustable pipette
US6295880A · kind A · utility
Inventor
Key dates
| Filing date | Dec 8, 1999 |
| Grant date | Oct 2, 2001 |
| Priority date | — |
| Expiry date | Dec 8, 2019 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01L3/0224
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An adjustable pipette includes a body containing a plunger assembly including a thumb button that is axially moved in alternating relatively shorter sample aspirating and relatively longer dispensing strokes. Guide slots in a guide sleeve receive a stop pin carried by a plunger shaft, and the slots define two axially and circumferentially spaced lower stops for aspirating and dispensing strokes respectively. The thumb button includes offset lobes that apply a rotational torque to the plunger shaft when pressed by the user. The user presses one lobe for an aspirating stroke to rotate the plunger shaft in one direction and align the stop pin with uppermost lower stops for a relatively short aspirating stroke and the user presses the other lobe for a dispensing stroke to rotate the plunger shaft in the other direction and align the stop pin with lowermost lower stops for a relatively long dispensing stroke. A window in the body permits the user to view and thereby understand the function of the lower stop selecting mechanism.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.