US3677685A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mold clamping mechanism of injection molding machine
Assignee: Individual
•
Filing: 1971-04-15
•
Granted: 1972-07-18
•
Expires: 1991-04-15
Abstract
Abstract A mold clamping mechanism of injection molding machine in which a high pressure mold clamping cylinder, a low pressure high speed mold closing cylinder and a high pressure switching cylinder are arranged in a series relation, said mold clamping cylinder and mold closing cylinder are interconnected with each other by way of an opening to pass the pressure oil, the forward portion of a high pressure switching piston in said switching cylinder is inserted through said opening to close said opening, a mold clamping ram in said clamping cylinder is forced ahead to close the mold by advancing a high speed mold closing piston in said mold closing cylinder, and said mold clamping ram is pushed by the supply of pressure oil through a passage in said switching piston to clamp the mold tightly.
Inventors
- 👤 Katashi Aoki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:46
CPC Classifications
B; B29; B29C; B29C45/00; B29C45/17; B29C45/64; B29C45/67
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
140 words
A mold clamping mechanism of injection molding machine in which a high pressure mold clamping cylinder, a low pressure high speed mold closing cylinder and a high pressure switching cylinder are arranged in a series relation, said mold clamping cylinder and mold closing cylinder are interconnected with each other by way of an opening to pass the pressure oil, the forward portion of a high pressure switching piston in said switching cylinder is inserted through said opening to close and open said opening, a mold clamping ram in said high pressure mold clamping cylinder is forced ahead to close the mold by advancing a low pressure high speed mold closing piston in said mold closing cylinder, and said clamping ram is pushed by the supply of pressure oil through a passage in said switching piston to clamp the mold tightly.
Claim 2
Dependent Claim
140 words
A mold clamping mechanism of injection molding machine in which a high pressure mold clamping cylinder, a low pressure high speed mold closing cylinder and a high pressure switching cylinder are arranged in a series relation, said mold clamping cylinder and mold closing cylinder are interconnected with each other by way of an opening to pass the pressure oil, the forward portion of a high pressure switching piston in said switching cylinder is inserted through said opening to close and open said opening, a mold clamping ram in said high pressure mold clamping cylinder is forced ahead to close the mold by advancing a low pressure high speed mold closing piston in said mold closing cylinder, and said clamping ram is pushed by the supply of pressure oil through a passage in said switching piston to clamp the mold tightly.
Claim 3
Dependent Claim
140 words
A mold clamping mechanism of injection molding machine as claimed in claim 1, in which said high pressure mold clamping ram is connected with the movable platen, said opening to pass through the pressure oil is formed on the wall between said mold clamping cylinder and said mold closing cylinder at the position corresponding to the center of said mold clamping cylinder head, the stroke of said low pressure closing piston is smaller than the stroke of said mold clamping ram, said mold clamping cylinder is formed integrally with said mold closing cylinder, said high pressure switching cylinder is passed through said opening to disconnect said mold clamping cylinder and said mold closing cylinder by filling said opening with the forward end portion of said switching piston, and said switching piston has a switching check valve in the piston head.
Claim 4
Dependent Claim
118 words
A mold clamping mechanism of injection molding machine as claimed in claim 2, in which said mold clamping cylinder and switching cylinder are interconnected with a pressure oil circuit having a check valve and the oil pressure of said circuit acts in the direction to retract said mold clamping ram and said switching piston, said pressure oil circuit is further connected with a change-over valve which is connected with the mold closing cylinder, the other side of said switching cylinder is connected with another pressure oil cIrcuit being provided with another high pressure oil change-over valve, and the latter pressure oil circuit is further connected with the former pressure oil circuit by way of a pilot check valve.
Claim 5
Dependent Claim
83 words
A mold clamping mechanism of injection molding machine as claimed in claim 2, in which a change-over valve which being connected to the oil pressure source is connected to the side of the mold clamping cylinder as to retract the mold clamping ram and the side of the mold closing cylinder as to advance the mold closing piston, and another change-over valve which being connected to said pressure source is connected with the side of switching cylinder as to advance the switching piston.
Claim 6
Dependent Claim
40 words
A mold clamping mechanism of injection molding machine as claimed in claim 1, in which said high speed mold closing low pressure piston is connected with a pair of plungers, and said low pressure piston is moved by said plungers.
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) | 1975-07-18 | 1976-01-17 | 1976-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-18 | 1980-01-17 | 1980-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-18 | 1984-01-17 | 1984-07-18 | $7700.00 | Window Closed / Lapsed |