US4495394A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic depth controller for EDM apparatus
Assignee: Raycon Corp
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Filing: 1984-06-05
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Granted: 1985-01-22
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Expires: 2004-06-05
Abstract
Abstract An electronic depth controller is associated with EDM apparatus for controlling the depth of holes which are machined in workpieces by the EDM apparatus. The electronic depth controller comprises its own microprocessor which acts upon selectable input data from a control panel to provide signals relating to hole depth control to the main control system of the EDM apparatus. The electronic depth controller is selectively operable to one or the other or both of two operating modes. Data relating to each mode is input to the system via switches on the control panel.
Inventors
- 👤 John R. McGregor
- 👤 Gary F. Rupert
- 👤 Thomas M. Kennedy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:52
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/182; B; B23; B23H; B23H7/00; B23H7/26; B23H7/30; G05B2219/00; G05B2219/30; G05B2219/34; G05B2219/34215; G05B2219/37; G05B2219/37106; G05B2219/43; G05B2219/43152; G05B2219/45; G05B2219/45137; G05B2219/45221; G05B2219/49; G05B2219/49237
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
338 words
In EDM apparatus for machining at least one hole in a workpiece via at least one electrode mounted on a holder, said EDM apparatus comprising means for advancing and retracting said holder and at least one electrode in unison toward and away from the workpiece, means for refeeding the at least one electrode on the holder, a main control system for controlling the advance and retraction of said holder and at least one electrode relative to the workpiece and for controlling machining operations, and a depth control system operatively associated with said main control system, said depth control system comprising sensor means providing a signal referenced to a reference datum and indicative of relative position of the holder to the workpiece in the direction of advancement and retraction, the improvement in said depth control system which comprises input means for presetting an initial amount of travel for said holder in the direction of advancement at the beginning of a machining operation, said input means including means for presetting an increment of travel for said holder in the direction of advancement subsequent to the initial amount of travel in the direction of advancement, a data register for depth limit data, means for comparing the data contents of said data register with said sensor means signal, and operating means comprising means for loading said data register with the initial amount of travel preset by said input means and for causing the holder to advance said initial amount of travel at the beginning of a machining operation, means operable upon completion of said initial amount of advance to execute a sub-cycle, said last-named means comprising means for causing a refeeding of the at least one electrode, means for updating the data contents of said data register by the increment of travel set by said input means and for thereafter causing the holder and the refed at least one electrode to advance to the updated depth limit, and means for causing said sub-cycle to be repeatedly executed a given number of times.
Claim 2
Dependent Claim
338 words
In EDM apparatus for machining at least one hole in a workpiece via at least one electrode mounted on a holder, said EDM apparatus comprising means for advancing and retracting said holder and at least one electrode in unison toward and away from the workpiece, means for refeeding the at least one electrode on the holder, a main control system for controlling the advance and retraction of said holder and at least one electrode relative to the workpiece and for controlling machining operations, and a depth control system operatively associated with said main control system, said depth control system comprising sensor means providing a signal referenced to a reference datum and indicative of relative position of the holder to the workpiece in the direction of advancement and retraction, the improvement in said depth control system which comprises input means for presetting an initial amount of travel for said holder in the direction of advancement at the beginning of a machining operation, said input means including means for presetting an increment of travel for said holder in the direction of advancement subsequent to the initial amount of travel in the direction of advancement, a data register for depth limit data, means for comparing the data contents of said data register with said sensor means signal, and operating means comprising means for loading said data register with the initial amount of travel preset by said input means and for causing the holder to advance said initial amount of travel at the beginning of a machining operation, means operable upon completion of said initial amount of advance to execute a sub-cycle, said last-named means comprising means for causing a refeeding of the at least one electrode, means for updating the data contents of said data register by the increment of travel set by said input means and for thereafter causing the holder and the refed at least one electrode to advance to the updated depth limit, and means for causing said sub-cycle to be repeatedly executed a given number of times.
Claim 3
Dependent Claim
58 words
The improvement set forth in claim 1, said input means further including means for presetting a number of said increments of travel and wherein said operating means comprises means for causing the total number of times said sub-cycle is executed to correspond to the number preset by said means for presetting a number of said increments of travel.
Claim 4
Dependent Claim
47 words
The improvement set forth in claim 1 including breakthrough sensing means for sensing breakthrough of one of said at least one electrodes through the workpiece, and means for causing the holder to repeatedly execute said increments of travel until breakthrough is sensed by said breakthrough sensing means.
Claim 5
Dependent Claim
70 words
The improvement set forth in claim 3 in which said operating means comprises means for causing one further update of the data contents of said data register and hence one further of said increments of travel to be executed after breakthrough is sensed by said breakthrough sensing means and for causing a refeeding of said at least one electrode before execution of said one further of said increments of travel.
Claim 6
Dependent Claim
32 words
The improvement set forth in claim 3 in which said breakthrough sensing means comprises means for sensing a predetermined acceleration in the travel of said holder which occurs in response to breakthrough.
Claim 7
Dependent Claim
80 words
The improvement set forth in claim 3, said input means further including means for presetting a number of said increments of travel, and said operating means comprising means for causing the total number of times said sub-cycle is executed to correspond to the number preset by said means for presetting a number of said increments of travel and for terminating machining operation if breakthrough has not been sensed by the time that such total number of sub-cycles has been executed.
Claim 8
Dependent Claim
56 words
The improvement set forth in claim 1 including breakthrough sensing means for sensing breakthrough of one of said at least one electrodes through the workpiece, and means providing a fault indication in response to sensing of breakthrough by said breakthrough sensing means during said initial amount of travel of said holder in the direction of advancement.
Claim 9
Dependent Claim
201 words
The improvement set forth in claim 1 wherein said depth control system comprises a microprocessor control containing two sets of operating instructions constituting two different operating modes and said input means further includes means for presetting another increment of travel for said holder in the direction of advancement subsequent to the initial amount of travel in the direction of advancement, said means for presetting an increment of travel for said holder in the direction of advancement subsequent to the initial amount of travel in the direction of advancement being associated with a first set of operating instructions, and said means for presetting another increment of travel for said holder in the direction of advancement subsequent to the initial amount of travel in the direction of advancement being associated with a second set of operating instructions, and selectable means for selecting which of said sets of instructions is to be executed, said first set of instructions acting upon said means for presetting an increment of travel and said second set of instructions acting upon said means for presetting another increment of travel, said microprocessor initially acting upon said initial amount of preset travel regardless of which set of operating instructions is selected.
Claim 10
Dependent Claim
161 words
The improvement set forth in claim 8, said input means further including means for presetting a number of said first-mentioned increments of travel and means for presetting a number of said another increment of travel, said means for presetting a number of said first-mentioned increments of travel being associated with said first set of operating instructions and said means for presetting a number of said another increments of travel being associated with said second set of operating instructions, said operating means comprising means for causing the total number of times said sub-cycle is executed, when said first set of instructions is selected, to correspond to the number set by said means for presetting a number of said first-mentioned increments of travel, and means for causing the total number of times said sub-cycle is executed, when said second set of instructions is selected, to correspond to the number set by said means for presetting a number of said another increment of travel.
Claim 11
Dependent Claim
102 words
The improvement set forth in claim 9 including breakthrough sensing means for sensing breakthrough of one of said at least one electrodes through the workpiece, said microprocessor control being operatively related with said breakthrough sensing means such that if breakthrough is sensed during said initial amount of travel of said holder, a fault signal is given, and such that if breakthrough is not sensed during execution of said second set of instructions, when said second set of instructions is selected, a fault indication is given at the conclusion of the holder having executed the preset number of said another increment of travel.
Claim 12
Dependent Claim
43 words
The improvement set forth in claim 10 in which said breakthrough sensing means comprises means for sensing change in the velocity of travel of said head and for providing said breakthrough signal in relation to a predetermined change in velocity of said head.
Claim 13
Dependent Claim
33 words
The improvement set forth in claim 9 in which said input means comprises plural input devices on a control panel, each device being assigned to provide a particular one of the preset inputs.
Claim 14
Dependent Claim
29 words
The improvement set forth in claim 12 including a visible readout display on said control panel providing a visible indication of the actual position of advancement of said holder.
Claim 15
Dependent Claim
32 words
The improvement set forth in claim 12 in which said input means are set in terms of either time or distance, or a derivative or derivatives thereof, such as velocity or acceleration.
Claim 16
Dependent Claim
78 words
The improvement set forth in claim 2, said input means further including means for presetting a further increment of travel for said holder in the direction of advancement subsequent to the initial amount of travel in the direction of advancement, and selectable means for selectively associating one of said means for presetting an increment of travel and said means for presetting a further increment of travel to the exclusion of the other for execution by said operating means.
Claim 17
Dependent Claim
324 words
In EDM apparatus for machining at least one hole in a workpiece via at least one electrode mounted on a holder, said EDM apparatus comprising means for advancing and retracting said holder and at least one electrode in unison toward and away form the workpiece, means for refeeding the at least one electrode on the holder, a main control system for controlling the advance and retraction of said holder and at least one electrode relative to the workpiece and for controlling machining operations, and a depth control system operatively associated with said main control system, said depth control system comprising sensor means providing a signal referenced to a reference datum and indicative of relative position of the holder to the workpiece in the direction of advancement and retraction, the improvement in said depth control system which comprises input means for presetting both an initial amount of travel to be traversed by said holder in the direction of advancement at the beginning of a machining operation and another increment of travel to be traversed by said holder in the direction of advancement subsequent to its traverse of the initial amount of travel in the direction of advancement, a data register for depth data, means for comparing the data contents of said data register with said sensor means signal, and operating means for depth control of a machining cycle including means operable at the beginning of a cycle for loading said data register with the initial amount of travel preset by said input means and for causing the holder to advance said initial amount of travel, and means operable during the conclusion of a cycle for causing the execution of one or more sub-cycles comprising a refeeding of the at least one electrode, an updating of the data contents of said data register by said another increment of travel, and an advancement of the holder and the refed at least one electrode to the updated depth.
Claim 18
Dependent Claim
324 words
In EDM apparatus for machining at least one hole in a workpiece via at least one electrode mounted on a holder, said EDM apparatus comprising means for advancing and retracting said holder and at least one electrode in unison toward and away form the workpiece, means for refeeding the at least one electrode on the holder, a main control system for controlling the advance and retraction of said holder and at least one electrode relative to the workpiece and for controlling machining operations, and a depth control system operatively associated with said main control system, said depth control system comprising sensor means providing a signal referenced to a reference datum and indicative of relative position of the holder to the workpiece in the direction of advancement and retraction, the improvement in said depth control system which comprises input means for presetting both an initial amount of travel to be traversed by said holder in the direction of advancement at the beginning of a machining operation and another increment of travel to be traversed by said holder in the direction of advancement subsequent to its traverse of the initial amount of travel in the direction of advancement, a data register for depth data, means for comparing the data contents of said data register with said sensor means signal, and operating means for depth control of a machining cycle including means operable at the beginning of a cycle for loading said data register with the initial amount of travel preset by said input means and for causing the holder to advance said initial amount of travel, and means operable during the conclusion of a cycle for causing the execution of one or more sub-cycles comprising a refeeding of the at least one electrode, an updating of the data contents of said data register by said another increment of travel, and an advancement of the holder and the refed at least one electrode to the updated depth.
Claim 19
Dependent Claim
38 words
The improvement set forth in claim 16 wherein said input means comprises an input device devoted exclusively to presetting said initial amount of travel and a second input device devoted exclusively to presetting said another increment of travel.
Claim 20
Dependent Claim
32 words
The improvement set forth in claim 17 in which said input means further includes a third input device devoted exclusively to presetting the number of sub-cycles to be executed during a cycle.
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) | 1988-01-22 | 1988-07-23 | 1989-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-01-22 | 1992-07-23 | 1993-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-01-22 | 1996-07-23 | 1997-01-22 | $7700.00 | Window Closed / Lapsed |