US3748866A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for chilling mold elements
Assignee: OI Glass Inc
•
Filing: 1971-04-23
•
Granted: 1973-07-31
•
Expires: 1991-04-23
Abstract
Abstract This disclosure relates to a method and apparatus for continuously chilling or cooling mold parts which are subjected to heated products, such as the die elements of a plastic blow molding apparatus. More particularly, the disclosed method and apparatus is adapted to maintain a predetermined mold chilling temperature to permit rapid forming of plastic articles and reduce the dwell time of the plastic article within the mold. The disclosed apparatus includes a heat exchanger-evaporator, a first liquid coolant loop communicating with the heat exchanger and the mold parts to be cooled, wherein low viscosity liquid coolant is pumped through the heat exchanger and the mold parts to chill the mold parts, and a second coolant loop communicating with the evaporator within the heat exchanger and including a compressor, condenser and expansion valve. The coolant in the second coolant loop is evaporated by the expansion valve, within the evaporator of the heat exchanger, to absorb heat from and chill the coolant within the first coolant loop.
Inventors
- 👤 J Heider
- 👤 T Schult
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:27
CPC Classifications
C; C03; C03B; C03B9/00; C03B9/30; C03B9/38; C03B9/3875; B; B29; B29C; B29C35/00; B29C35/007; C03B9/3808; C03B9/3816; F; F28; F28C; F28C3/00; F28C3/005; F25; F25B; F25B2400/00; F25B2400/13
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
174 words
In a continuous plastic molding apparatus having opposed, relatively movable die elements receiving molten plastic material for forming plastic articles, the improvement comprising: a heat exchanger having an evaporator therein, a first continuous coolant loop having trichlorofluoromethane coolant therein communicating with said heat exchanger and the surfaces of said die elements opposite the die forming faces which are cyclicly heated to a high temperature over short time intervals, and a second coolant loop having a relatively volatile coolant therein communicating with said heat exchanger, a condenser adapted to condense the volatile coolant within said second coolant loop and an expansion valve means adapted to vaporize the volatile coolant within said evaporator, whereby the coolant within said first coolant loop is circulated and remains in the liquid state under pressure from said heat exchanger to repeatedly chill said die elements, and the heat of said molten plastic material is first absorbed by the trichlorofluoromethane coolant circulated in said first coolant loop and is later absorbed by the second relatively volatile coolant within said heat exchanger.
Claim 2
Dependent Claim
174 words
In a continuous plastic molding apparatus having opposed, relatively movable die elements receiving molten plastic material for forming plastic articles, the improvement comprising: a heat exchanger having an evaporator therein, a first continuous coolant loop having trichlorofluoromethane coolant therein communicating with said heat exchanger and the surfaces of said die elements opposite the die forming faces which are cyclicly heated to a high temperature over short time intervals, and a second coolant loop having a relatively volatile coolant therein communicating with said heat exchanger, a condenser adapted to condense the volatile coolant within said second coolant loop and an expansion valve means adapted to vaporize the volatile coolant within said evaporator, whereby the coolant within said first coolant loop is circulated and remains in the liquid state under pressure from said heat exchanger to repeatedly chill said die elements, and the heat of said molten plastic material is first absorbed by the trichlorofluoromethane coolant circulated in said first coolant loop and is later absorbed by the second relatively volatile coolant within said heat exchanger.
Claim 3
Independent Claim
160 words
A method of continuously chilling opposed, relatively movable die elements of a continuous plastic molding apparatus, said die elements being repeatedly heated to high temperatures over short time intervals by receiving molten plastic material for forming plastic articles, comprising the steps of: a. circulating trichlorofluoromethane liquid coolant, under pressure, into heat transfer contact with the surfaces of said die elements, opposite the die forming faces, b. circulating said trichlorofluoromethane coolant from said mold parts to a heat exchanger, wherein the temperature of the liquid coolant is reduced by a relativEly volatile coolant, thereby maintaining the trichlorofluoromethane coolant in a liquid state, c. evaporating said relatively volatile coolant within said heat exchanger, transferring the heat absorbed by said trichlorofluoromethane coolant from said surfaces of said die elements to said relatively volatile coolant, vaporizing said relatively volatile coolant, and d. circulating said relatively volatile coolant vapor to a condenser, wherein said volatile coolant is condensed, cooled and recirculated to said heat exchanger.
Claim 4
Independent Claim
160 words
A method of continuously chilling opposed, relatively movable die elements of a continuous plastic molding apparatus, said die elements being repeatedly heated to high temperatures over short time intervals by receiving molten plastic material for forming plastic articles, comprising the steps of: a. circulating trichlorofluoromethane liquid coolant, under pressure, into heat transfer contact with the surfaces of said die elements, opposite the die forming faces, b. circulating said trichlorofluoromethane coolant from said mold parts to a heat exchanger, wherein the temperature of the liquid coolant is reduced by a relativEly volatile coolant, thereby maintaining the trichlorofluoromethane coolant in a liquid state, c. evaporating said relatively volatile coolant within said heat exchanger, transferring the heat absorbed by said trichlorofluoromethane coolant from said surfaces of said die elements to said relatively volatile coolant, vaporizing said relatively volatile coolant, and d. circulating said relatively volatile coolant vapor to a condenser, wherein said volatile coolant is condensed, cooled and recirculated to said heat exchanger.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-30 | 1977-01-29 | 1977-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-30 | 1981-01-29 | 1981-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-30 | 1985-01-29 | 1985-07-31 | $7700.00 | Window Closed / Lapsed |