US4846253A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for compressing foundry moulding material by means of compressed gas
Assignee: BMD Badische Maschinenfabrik Durlach GmbH
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Filing: 1988-01-20
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Granted: 1989-07-11
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Expires: 2008-01-20
Abstract
Abstract An apparatus for the compression of foundry moulding material by compressed gas, which comprises a pressure tank for the compressed gas forming an inlet pressure zone, a moulding zone positioned beneath the same constituted by a moulding box with filling frame and pattern plate with pattern, onto which the moulding material is loosely poured prior to compression, and a large-area valve arranged between the pressure tank and the moulding zone. The closure member thereof frees the valve opening in the pressure tank in a few milliseconds and moves into the inlet pressure zone. The closure member is driven by a pressure cylinder, whose piston on the lift side forms the moveable termination of a gas-pressurized pressure reservoir and by its opposite side is connected to a high pressure source. The high pressure-side outflow is constructed in such a way that the pressure medium flows out at a speed of more than 10 m/s, accompanied by the simultaneous acceleration of the piston, under the pressure in the pressure reservoir and the closure member into the raised open position.
Inventors
- 👤 Norbert Damm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 11:13
CPC Classifications
B; B22; B22C; B22C15/00
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
253 words
An apparatus for compressing foundry moulding material by compressed gas, the apparatus comprising: a pressure tank for the compressed gas including an inlet pressure chamber; a moulding zone located beneath the inlet pressure chamber including a moulding box with a filling frame and a pattern plate with a pattern terminating the moulding box at a bottom thereof and onto which the moulding material is loosely poured prior to a compression; a large-area valve located between the pressure tank and the moulding zone, said large area valve including at least one valve opening and a valve closure member cooperable with at least one valve opening to open and close the same; means for moving the closure member into a closed position covering at least one valve opening and an open position uncovering the at least one valve opening including a driving pressure piston disposed in a pressure cylinder and connected to said valve closure member; a pressure reservoir subject to an action of gas, formed on a lifting side of the pressure piston; a hydraulic high pressure source connected to the pressure piston on an opposite side from said pressure reservoir; means for enabling a high pressure-side outflow so as to cause a pressure medium to flow out at a speed of >10 m/s, with a simultaneous acceleration of the pressure piston; means to accelerate the pressure piston simultaneously with said high pressure-side outflow by pressure in the pressure reservoir to raise the closure member into the inlet pressure chamber to the open position.
Claim 2
Independent Claim
253 words
An apparatus for compressing foundry moulding material by compressed gas, the apparatus comprising: a pressure tank for the compressed gas including an inlet pressure chamber; a moulding zone located beneath the inlet pressure chamber including a moulding box with a filling frame and a pattern plate with a pattern terminating the moulding box at a bottom thereof and onto which the moulding material is loosely poured prior to a compression; a large-area valve located between the pressure tank and the moulding zone, said large area valve including at least one valve opening and a valve closure member cooperable with at least one valve opening to open and close the same; means for moving the closure member into a closed position covering at least one valve opening and an open position uncovering the at least one valve opening including a driving pressure piston disposed in a pressure cylinder and connected to said valve closure member; a pressure reservoir subject to an action of gas, formed on a lifting side of the pressure piston; a hydraulic high pressure source connected to the pressure piston on an opposite side from said pressure reservoir; means for enabling a high pressure-side outflow so as to cause a pressure medium to flow out at a speed of >10 m/s, with a simultaneous acceleration of the pressure piston; means to accelerate the pressure piston simultaneously with said high pressure-side outflow by pressure in the pressure reservoir to raise the closure member into the inlet pressure chamber to the open position.
Claim 3
Dependent Claim
25 words
An apparatus according to claim 1, wherein the pressure cylinder is provided on high pressure side with a small displacement volume, of between 150-500 cc.
Claim 4
Independent Claim
46 words
An apparatus according to one of claims 1 or 2, wherein control members are provided for shutting off the high pressure-side out flow from a remaining high pressure circuit, and wherein the high pressure outflow is connected by a large cross-section line to a drain tank.
Claim 5
Dependent Claim
20 words
An apparatus according to claim 3, wherein the pressure of the high pressure source is between 100 and 300 bar.
Claim 6
Dependent Claim
29 words
An apparatus according to claim 4, wherein the pressure reservoir in the closed position of the closure member is under an inlet pressure of between 20 and 50 bar.
Claim 7
Dependent Claim
32 words
An apparatus according to claim 5, wherein a ratio of a volume of the pressure reservoir to a displacement volume of the pressure cylinder is in a range of at least 5:1.
Claim 8
Dependent Claim
33 words
An apparatus according to claim 5, wherein a ratio of a volume of the pressure reservoir to a displacement volume of the pressure cylinder is in a range of from 10:1 to 15:1.
Claim 9
Dependent Claim
35 words
An apparatus according to claim 6, wherein the pressure reservoir comprises a gas-filled cylinder terminated by a movable piston connected on a source opposite to the gas pressure side to said hydraulic high pressure side.
Claim 10
Dependent Claim
29 words
An apparatus according to claim 8, wherein at least one of a throttle and restrictor acting towards the end of the lift movement of the pressure piston is provided.
Claim 11
Dependent Claim
34 words
An apparatus according to claim 9, wherein the piston has a piston rod extending into a high pressure-side cylinder zone and has a conical thickened portion cooperating with a constriction in said cylinder zone.
Claim 12
Dependent Claim
44 words
An apparatus according to claim 1, wherein a control slide valve, a check valve, and a ring main are provided for connecting the high pressure source to the pressure cylinder, and wherein a controllable check valve connects the ring main to a drain tank.
Claim 13
Dependent Claim
80 words
An apparatus according to claim 11, wherein the control slide valve connects the pressure cylinder to the high pressure source in a first position and pressure-relieves a control line of the controllable check valve, so that the latter closes, while in a second position the control slide valve connects the control line to the high pressure source, so that the check valve opens counter to the pressure in the ring main and connects the pressure cylinder to the drain tank.
Claim 14
Dependent Claim
88 words
An apparatus according to claim 1, wherein a control slide valve connects the pressure reservoir to the hydraulic high pressure source, and wherein, in a first position, the control slide valve connects the pressure reservoir to the high pressure source, so that the gas in the pressure reservoir and on the lift side in the pressure cylinder is compressed to the final pressure, while high pressure simultaneously prevails on the opposite side of the pressure piston and, in a second position, provides a connection with a drain tank.
Claim 15
Dependent Claim
20 words
An apparatus according to claim 1, wherein the pressure of the high pressure source is between 100 and 300 bar.
Claim 16
Dependent Claim
29 words
An apparatus according to claim 1, wherein the pressure reservoir in the closed position of the closure member is under an inlet pressure of between 20 and 50 bar.
Claim 17
Dependent Claim
28 words
An apparatus according to claim 1, wherein a ratio of a volume of the pressure reservoir to a displacement volume of the pressure piston is at least 5:1.
Claim 18
Dependent Claim
26 words
An apparatus according to claim 16, wherein a ratio of a volume of the pressure reservoir to the displacement volume of the pressure piston is 10:1-15:1.
Claim 19
Dependent Claim
35 words
An apparatus according to claim 1, wherein the pressure reservoir comprises a gas-filled cylinder terminated by a movable piston connected on a side opposite to the gas pressure side to said hydraulic high pressure source.
Claim 20
Dependent Claim
29 words
An apparatus according to claim 1, wherein at least one of a throttle and restrictor acting towards the end of the lift movement of the pressure piston is provided.
Claim 21
Dependent Claim
34 words
An apparatus according to claim 14, wherein the piston has a piston rod extending into a high pressure-side cylinder zone and has a conical thickened portion cooperating with a constriction in said cylinder zone.
Claim 22
Dependent Claim
45 words
An apparatus according to claim 1, wherein the means for enabling a high pressure-side outflow includes a first drain line connecting the high pressure-side of the pressure reservoir to a drain tank and a second drain line connecting the drain tank to a hydraulic tank.
Claim 23
Dependent Claim
14 words
An apparatus according to claim 21, wherein the drain tank includes a vent line.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-07-10 | 1993-01-09 | 1993-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-10 | 1997-01-09 | 1997-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-10 | 2001-01-09 | 2001-07-11 | $7700.00 | Window Closed / Lapsed |