Fluid replacement system for hydraulic actuators for glass sheet shaping molds and method of press bending glass sheets
US4276074A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 13, 1979 |
| Grant date | Jun 30, 1981 |
| Priority date | — |
| Expiry date | Sep 13, 1999 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03B23/0302
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Hydraulic fluid actuated pistons are operatively connected to shaping molds used to shape glass sheets by moving the molds between a glass-engaging position and a retracted position. The piston is movably mounted within a piston cylinder to form two chambers. Hydraulic fluid is applied under pressure alternately to one or the other chamber to actuate movement of the piston and the glass sheet shaping mold connected to the piston. When hydraulic fluid is applied under pressure, it tends to become heated to a temperature at which the hydraulic fluid carbonizes and/or foams. Either of these occurrences reduces the efficiency of the hydraulic fluid to actuate uniform piston motion. Means is provided to insure that hot hydraulic fluid removed from one of the chambers is delivered to the upper portion of a storage reservoir where it is cooled before it is returned to the piston cylinder from the lower portion of the storage reservoir, thereby insuring a continuous supply of cold hydraulic fluid for piston actuation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.