Thermal barrier for poppet valve
US4346870A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 26, 1980 |
| Grant date | Aug 31, 1982 |
| Priority date | — |
| Expiry date | Nov 26, 2000 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02B3/06
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
Thermal barriers (10, 26) fixed to mushroomed heads (12, 28) of poppet valves intended for diesel engines are disclosed. Thermal barrier (10) includes an insulating material (18) bonded to a face portion (12a) of mushroom head (12), a sheet metal shield (20) covering the insulating material, and a flange (22) clamped over the outer periphery of the shield and welded to the valve head. Thermal barrier (26) includes an insulating material encapsulated in a sheet metal sheath defining an evacuated chamber (32) which covers a face portion (28a) of the mushroom head (28), a sheet metal shield (30), and a flange portion (28b) integrally formed with the mushroom head and spun over the shield during final assembly to clamp the shield over the encapsulated insulating material. The flanges in both embodiments make line contact with the shield to minimize heat flow from the shields to the flanges and hence to the valve head.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.