US3786725A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic type mold clamping device
Assignee: Individual
•
Filing: 1972-07-05
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Granted: 1974-01-22
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Expires: 1992-07-05
Abstract
Abstract A mold clamping device of hydraulic type having a mold clamping cylinder including a mold clamping piston coupled through a ram portion thereof to a movable plate for supporting a movable mold, and a high-speed mold shifting cylinder including a mold shifting piston associated with said mold clamping piston through a rod portion thereof, according to the invention, said device further comprising a passage interconnecting two chambers formed at both sides of said mold clamping piston in said mold clamping cylinder, and a valve located in said passage for opening and closing the passage in accordance with the operation of the mold clamping device, while said two chambers are connected to hydraulic lines through portions of said passage at corresponding sides of said valve.
Inventors
- 👤 K Aoki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 05:18
CPC Classifications
B; B29; B29C; B29C45/00; B29C45/17; B29C45/64; B29C45/67; B29C45/6764; B29C45/6771
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
142 words
In a mold clamping device of hydraulic type having a mold clamping cylinder including a mold clamping piston coupled through a ram portion thereof to a movable plate for supporting a movable mold, and a high-speed mold shifting cylinder including a mold shifting piston associated with said mold clamping piston through a rod portion thereof, the improvement comprising: A a passage interconnecting two chambers constituting mold opening and closing chambers respectively formed at opposite sides of said mold clamping piston in said mold clamping cylinder; B a valve located in said passage for opening and closing the passage in accordance with the operation of the mold clamping device; and C said mold opening and closing chambers being connected to hydraulic lines through portions of said passage and selectively in communication therewith upon movement of said valve to passage opening and closing positions.
Claim 2
Dependent Claim
142 words
In a mold clamping device of hydraulic type having a mold clamping cylinder including a mold clamping piston coupled through a ram portion thereof to a movable plate for supporting a movable mold, and a high-speed mold shifting cylinder including a mold shifting piston associated with said mold clamping piston through a rod portion thereof, the improvement comprising: A a passage interconnecting two chambers constituting mold opening and closing chambers respectively formed at opposite sides of said mold clamping piston in said mold clamping cylinder; B a valve located in said passage for opening and closing the passage in accordance with the operation of the mold clamping device; and C said mold opening and closing chambers being connected to hydraulic lines through portions of said passage and selectively in communication therewith upon movement of said valve to passage opening and closing positions.
Claim 3
Dependent Claim
75 words
A mold clamping device as claimed in claim 1, the diameter of said ram portion being greater than that of said portion whereby the cross sectional areas of said two chambers in the mold clamping cylinder are different, said high-speed mold shifting piston dividing said mold shifting cylinder into high-speed mold opening and closing chambers, and a hydraulic line connected to said mold opening one of said chambers formed in said high-speed mold shifting cylinder.
Claim 4
Dependent Claim
96 words
A mold clamping device as claimed in claim 1, wherein the diameter of said rod portion is greater than that of said ram portion, said rod portion having a hollow, cylindrical space therein, a nozzle having an oil passage therethrough telescopically extending into said space, said mold shifting piston dividing said mold shifting cylinder into high-speed mold opening and closing chambers, a hydraulic line connected to said nozzle, whereby, upon introduction of fluid under pressure into said nozzle, said rod portion is shifted at high speed together with said ram portion to a mold closing position.
Claim 5
Dependent Claim
135 words
A mold clamping device as claimed in claim 1, the diameters of said rod portion and said ram portion being equal, said mold shifting piSton dividing said mold shifting cylinder into high-speed mold opening and closing chambers, said rod portion having a hollow, cylindrical space therein, a nozzle having an oil passage therethrough and extending into said space, a hydraulic line connected to said nozzle operable to introduce fluid under pressure into said nozzle, whereby said rod portion is shifted at high speed together with said ram portion to a mold closing position, a hydraulic line connected to said high-speed mold opening chamber and operable upon introduction of fluid under pressure into said high-speed mold opening chamber to shift said rod portion at high speed together with said ram portion to a mold opening position.
Claim 6
Dependent Claim
96 words
A mold clamping device as claimed in claim 4, said valve including a shaft portion having an axially extended hole therethrough and a piston portion formed around said shaft portion, said valve including a body in which said valve is positioned, said piston portion dividing a cylinder of the valve body into two chambers of equal cross sectional areas, hydraulic lines connected to said two chambers in said valve body for introduction selectively of fluid pressures therein, fluid pressures acting at opposite sides of said piston portion being balanced through said hole in said shaft portion.
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) | 1977-01-21 | 1977-07-23 | 1978-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-21 | 1981-07-23 | 1982-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-21 | 1985-07-23 | 1986-01-22 | $7700.00 | Window Closed / Lapsed |