US3662142A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Edm machine head and hydraulic pressure apparatus
Assignee: Essar Corp
•
Filing: 1970-12-08
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Granted: 1972-05-09
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Expires: 1990-12-08
Abstract
Abstract An electrical discharge machining device or EDM machine having a head carrying an electrode which is movable toward and away from a work piece by a hydraulically operated double acting cylinder. A control valve, combined with a servo solenoid and manually operated lever, is operable to control the flow of hydraulic fluid to the cylinder. A light responsive electrical control operates the servo solenoid in response to the size of the electrical discharge gap between the electrode and the work piece. Interposed in the fluid line to the hydraulic cylinder is a lock valve operable to lock the cylinder and fix the position of the electrode relative to the work piece. The manually controlled lever is operable to engage switches to override the lock valve control during the electrical machining and elevation of the electrode operations of the device. Hydraulic pressure is continuously supplied to the control valve from a pair of liquid storing chambers connected to the control valve with a switching valve. Fluid under pressure in either one of the chambers operates the switching valve to provide a continuous source of hydraulic fluid under pressure to the control valve. The head contains the hydraulic pressure source, control valve, EDM power supply, electric control circuit for the valve and the double acting cylinder.
Inventors
- 👤 Sven O Olsson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 13:52
CPC Classifications
B; B23; B23H; B23H7/00; B23H7/14; B23H7/18; B23H7/26; B23H7/265
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
227 words
An electrical discharge machine head for machining a work piece comprising: frame means, a movable member mounted on the frame means adapted to carry an electrode and selectively move the electrode toward and away from the work piece, hydraulic cylinder means mounted on the frame means and operably connected to the movable member to move the movable member relative to the frame means, an apparatus for supplying a source of hydraulic fluid under pressure mounted on the frame means, a control valve mounted on the frame means for controlling the supply of hydraulic fluid from the apparatus to the cylinder means, thereby controlling the movement of the movable member relative to the frame means, and control means mounted on the frame means to actuate the control valve, said control means having an electrically operated control operable in response to cutting voltage between the electrode and work piece to actuate the valve and manually operated means operably connected to the electrically operated means, said manually operated means having a member movable to a position to override the electrically operated control to actuate the valve and thus selectively move the electrode toward and away from the work piece independently of the electrically operated control, and means connecting the electrically operated means with the manually operated means whereby the electrically operated control can operate independently of the manually operated means.
Claim 2
Dependent Claim
227 words
An electrical discharge machine head for machining a work piece comprising: frame means, a movable member mounted on the frame means adapted to carry an electrode and selectively move the electrode toward and away from the work piece, hydraulic cylinder means mounted on the frame means and operably connected to the movable member to move the movable member relative to the frame means, an apparatus for supplying a source of hydraulic fluid under pressure mounted on the frame means, a control valve mounted on the frame means for controlling the supply of hydraulic fluid from the apparatus to the cylinder means, thereby controlling the movement of the movable member relative to the frame means, and control means mounted on the frame means to actuate the control valve, said control means having an electrically operated control operable in response to cutting voltage between the electrode and work piece to actuate the valve and manually operated means operably connected to the electrically operated means, said manually operated means having a member movable to a position to override the electrically operated control to actuate the valve and thus selectively move the electrode toward and away from the work piece independently of the electrically operated control, and means connecting the electrically operated means with the manually operated means whereby the electrically operated control can operate independently of the manually operated means.
Claim 3
Dependent Claim
33 words
The device of claim 1 wherein: said frame means includes a support member, said apparatus for supplying a source of hydraulic fluid under pressure and control valve being mounted on the support member.
Claim 4
Dependent Claim
18 words
The device of claim 8 wherein: said control means for the valve is mounted on the support member.
Claim 5
Dependent Claim
24 words
The device of claim 1 wherein: said manually operated means comprises a lever movable to control the valve independently of the electrically operated control.
Claim 6
Dependent Claim
61 words
The device of claim 1 wherein: the movable member comprises a block and guide rods secured to the block, said guide rods being slidably mounted in the frame means in a direction to selectively move the electrode toward and away from the work piece, said hydraulic cylinder means comprising a double acting cylinder having a movable member connected to the block.
Claim 7
Dependent Claim
339 words
An electrical discharge machine head for machining a work piece comprising: frame means, a movable member mounted on the frame means adapted to carry an electrode and selectively move the electrode toward and away from the work piece, hydraulic cylinder means mounted on the frame means and operably connected to the movable member to move the movable member relative to the frame means, apparatus for supplying a source of hydraulic fluid under pressure mounted on the frame means, said apparatus having a first means having a first liquid storing Chamber, a second means having a second liquid storing chamber, first valve means connected to pneumatic fluid supply and to upper portions of said first chamber and said second chamber, said first valve means having a first position to direct pneumatic fluid to said first chamber and exhaust pneumatic fluid from said second chamber, and a second position to exhaust pneumatic fluid from the first chamber and direct pneumatic fluid to the second chamber, first control means operable to selectively locate the first valve means in the first position and second position, second valve means connected to hydraulic fluid inlet means and return means and to lower portions of said first chamber and said second chamber, said second valve means having a first position to direct pressurized hydraulic fluid from the first chamber to the inlet of the control valve and to direct hydraulic fluid from the return of the control valve to the second chamber and a second position to direct pressurized hydraulic fluid from the second chamber to the inlet of the control valve and to direct hydraulic fluid from the return of the control valve to the first chamber, and second control means to operate said second valve, control valve means mounted on the frame means for controlling the supply of hydraulic fluid from the apparatus to the cylinder means thereby controlling the movement of the movable member relative to the frame means, and control means mounted on the frame means to actuate the control valve means.
Claim 8
Dependent Claim
339 words
An electrical discharge machine head for machining a work piece comprising: frame means, a movable member mounted on the frame means adapted to carry an electrode and selectively move the electrode toward and away from the work piece, hydraulic cylinder means mounted on the frame means and operably connected to the movable member to move the movable member relative to the frame means, apparatus for supplying a source of hydraulic fluid under pressure mounted on the frame means, said apparatus having a first means having a first liquid storing Chamber, a second means having a second liquid storing chamber, first valve means connected to pneumatic fluid supply and to upper portions of said first chamber and said second chamber, said first valve means having a first position to direct pneumatic fluid to said first chamber and exhaust pneumatic fluid from said second chamber, and a second position to exhaust pneumatic fluid from the first chamber and direct pneumatic fluid to the second chamber, first control means operable to selectively locate the first valve means in the first position and second position, second valve means connected to hydraulic fluid inlet means and return means and to lower portions of said first chamber and said second chamber, said second valve means having a first position to direct pressurized hydraulic fluid from the first chamber to the inlet of the control valve and to direct hydraulic fluid from the return of the control valve to the second chamber and a second position to direct pressurized hydraulic fluid from the second chamber to the inlet of the control valve and to direct hydraulic fluid from the return of the control valve to the first chamber, and second control means to operate said second valve, control valve means mounted on the frame means for controlling the supply of hydraulic fluid from the apparatus to the cylinder means thereby controlling the movement of the movable member relative to the frame means, and control means mounted on the frame means to actuate the control valve means.
Claim 9
Dependent Claim
50 words
The device of claim 6 wherein: the second control means includes a first pilot valve connected to the first chamber and a second pilot valve connected to the second chamber, said pilot valves operable to actuate the second valve in response to the application of pressure to either pilot valve.
Claim 10
Dependent Claim
32 words
The apparatus of claim 6 wherein: the first control means includes switch means in response to the level of hydraulic fluid in at least one chamber to selectively operate the first valve.
Claim 11
Dependent Claim
69 words
The device of claim 6 wherein: the control means comprises an electric control operable in response to cutting voltage between the electrode and work piece to actuate the valve and manually operated means operably connected to the valve to selectively override and de-energize the electric control means to actuate the valve and thus move the electrode toward and away from the work piece independently of the electric control means.
Claim 12
Dependent Claim
32 words
The device of claim 9 wherein: the manually operated means comprises a lever movably mounted on the frame means to control the position of the valve independently of the electric control means.
Claim 13
Dependent Claim
33 words
The device of claim 6 wherein: said frame means includes a support means, said apparatus for supplying a source of hydraulic fluid under pressure and control valve being mounted on the support means.
Claim 14
Dependent Claim
18 words
The device of claim 6 wherein: said control means for the valve is mounted on the support means.
Claim 15
Dependent Claim
33 words
The device of claim 6 wherein: the first control means includes switch means operable in response to the level of hydraulic fluid in at least one chamber to selectively operate the first valve.
References Cited (Backward Citations)
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US2762946A
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US2989616A
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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) | 1975-05-09 | 1975-11-08 | 1976-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-09 | 1979-11-08 | 1980-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-09 | 1983-11-08 | 1984-05-09 | $7700.00 | Window Closed / Lapsed |