Fluid transfer apparatus
US3972683A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 7, 1974 |
| Grant date | Aug 3, 1976 |
| Priority date | — |
| Expiry date | Jun 7, 1994 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01L3/0217
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
There is disclosed apparatus for aspirating and dispensing a liquid sample which includes a storage cylinder within which is included a freely moving solid cylinder. Attached to the storage cylinder is an aspirating cylinder or needle, which is inserted into the sample. Both the storage cylinder and needle are initially filled with water. Before aspirating the sample, a slight amount of water is removed from the storage cylinder resulting in air being aspirated through the needle. Then, the needle is inserted in the sample and water continues to be removed from the storage cylinder, resulting in the sample being aspirated through the needle. The aspirated sample and water are separated by the previously aspirated air, which creates a bubble in the storage cylinder. This bubble lifts the movable solid cylinder in the storage cylinder as the sample is aspirated. After a desired amount of sample is aspirated, discrete amounts of water are added to the storage cylinder, thereby causing discrete amounts of sample to be dispensed through the needle. The water pressure on the solid cylinder resting against the bubble expands the bubble against the inner surface of the storage cylinder, th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.