Extensible shafts and fishing spears
US3932953A · kind A · utility
Inventor
Key dates
| Filing date | Mar 18, 1975 |
| Grant date | Jan 20, 1976 |
| Priority date | — |
| Expiry date | Mar 18, 1995 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA01K81/00
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A telescopically extensible and collapsible shaft, particularly for such as an underwater hand spear for spearing fish, with an arrangement for locking or rigidly securing the shaft in the extended position including a cylindrical extension part telescopically located in a tubular main part and having liquid seal means between the extension part inner end and the main part. A butt end piece is adapted to close the end of the main part remote from the end through which the extension part extends and has an inlet passage whereby water can be drawn into the main tubular part on extension of the extension part (and subsequently ejected on telescopically collapsing the extension part into the main part), the butt end piece being adjustable relative to the main part to open the inlet passage for the admission of water and closed to seal the water in the extended shaft.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.