Apparatus for applying a foamable resin
US5339991A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 15, 1992 |
| Grant date | Aug 23, 1994 |
| Priority date | — |
| Expiry date | Dec 15, 2012 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29B7/7438
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The foam application apparatus or gun of this invention is particularly adapted to prevent leakage of the gun through the nozzle while assuring repeated use without seizure. The foam application apparatus includes a cylindrical mixing chamber having two inlet passages and an outlet passage through which mixed foamable resin is sprayed or discharged under pressure. A cylindrical valve rod having a free end is reciprocated in the mixing chamber from an "off" position, wherein the rod free end blocks the communication from the inlet passages to the outlet passage, and "on " position, wherein the rod is retracted, providing unrestricted communication between the inlet and outlet passages. In one preferred embodiment, a pair of closely spaced radial grooves are provided on the free end of the valve rod. The grooves receive fluid resin to form in situ resin seals which are replenished each time the rod is reciprocated in the chamber. The grooves are preferably spaced sufficiently close to form a thin film interconnecting the fluid resin in the grooves to form a continuous seal. Seizure is prevented by machining the mating cylindrical surfaces of the rod and chamber to very accurate toler…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.