US3891126A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Injection cylinders of die cast machines
Assignee: Shibaura Machine Co Ltd
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Filing: 1973-11-05
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Granted: 1975-06-24
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Expires: 1993-11-05
Abstract
Abstract In an injection cylinder of a die cast machine of the class wherein the piston of the cylinder is operated by pressurized fluid, the piston is moved in the forward direction for performing injection moulding by the expansion of gas contained in a gas accumulator and the piston is moved in the rearward direction by pressurized liquid. When the piston is moved in the forward direction the flow rate of the pressurized liquid discharged from the cylinder is controlled by means of a flow control valve.
Inventors
- 👤 Kazuyoshi Segawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:23
CPC Classifications
B; B22; B22D; B22D17/00; B22D17/20; B22D17/32
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
188 words
In an injection cylinder of a die cast machine of the class wherein the piston of the cylinder is moved in forward and rearward directions by admitting and discharging pressurized fluid into and out of said cylinder, the improvement which comprises a gas accumulator containing pressurized gas and a predetermined quantity of liquid, said predetermined quantity of liquid being used for adjusting the pressure of the gas contained in said accumulator, said gas accumulator having substantially larger volume than said cylinder, a flow control valve connected between said cylinder and said gas accumulator for admitting said gas into said cylinder thereby moving said piston in the forward direction by the expansion of said pressurized gas for performing die casting, a source of pressurized liquid, means operatively coupled for admitting said pressurized liquid into said cylinder on the opposite side of said piston to move the same in the rearward direction thereby compressing the gas in said gas accumulator, and means operatively coupled for controlling the flow rate of said pressurized liquid while the liquid is discharged from said cylinder when said piston is moved in the forward direction.
Claim 2
Dependent Claim
188 words
In an injection cylinder of a die cast machine of the class wherein the piston of the cylinder is moved in forward and rearward directions by admitting and discharging pressurized fluid into and out of said cylinder, the improvement which comprises a gas accumulator containing pressurized gas and a predetermined quantity of liquid, said predetermined quantity of liquid being used for adjusting the pressure of the gas contained in said accumulator, said gas accumulator having substantially larger volume than said cylinder, a flow control valve connected between said cylinder and said gas accumulator for admitting said gas into said cylinder thereby moving said piston in the forward direction by the expansion of said pressurized gas for performing die casting, a source of pressurized liquid, means operatively coupled for admitting said pressurized liquid into said cylinder on the opposite side of said piston to move the same in the rearward direction thereby compressing the gas in said gas accumulator, and means operatively coupled for controlling the flow rate of said pressurized liquid while the liquid is discharged from said cylinder when said piston is moved in the forward direction.
Claim 3
Dependent Claim
45 words
The injection cylinder according to claim 1 wherein said flow controlling means is comprised of a valve and further comprising a check valve connected in parallel with said valve, said check valve opening when the pressurized liquid is admitted into said cylinder from said source.
Claim 4
Dependent Claim
31 words
The injection cylinder according to claim 1 which further comprises an accumulator for said pressurized liquid and a normal open valve connecting said liquid accumulator to said source of pressurized liquid.
Claim 5
Dependent Claim
25 words
The injection cylinder according to claim 1 wherein said flow rate controlling means comprises a plurality of flow control valves for providing different flow rates.
Claim 6
Dependent Claim
52 words
The injection cylinder according to claim 1 which further comprises a pilot check valve connected in the conduit of said pressurized liquid and an electrically operated valve means for normally holding said pilot valve in an opened state so that said pilot check valve is closed when supply of electricity is interrupted.
Claim 7
Dependent Claim
20 words
The injection cylinder according to claim 1 wherein the quantity of said liquid contained in said gas accumulator is variable.
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) | 1978-06-23 | 1978-12-23 | 1979-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-23 | 1982-12-23 | 1983-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-23 | 1986-12-23 | 1987-06-24 | $7700.00 | Window Closed / Lapsed |