US3579053A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetizing and demagnetizing apparatus and method
Assignee: Individual
•
Filing: 1968-06-26
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Granted: 1971-05-18
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Expires: 1988-06-26
Abstract
Abstract Apparatus for magnetizing and demagnetizing, including means for adjustable controlling the current and voltage applied to the object to be magnetized, for thereby controlling the speed of magnetic saturation to more accurately sense the level of saturation in the demagnetizing steps.
Inventors
- 👤 Arthur K Littwin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:05
CPC Classifications
B; B23; B23Q; B23Q3/00; B23Q3/15
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
235 words
Apparatus for demagnetizing a magnet which includes necessarily magnetizing it in the steps of demagnetizing it, comprising a. circuit means including the magnet and adapted for connection with an electrical source which includes means for applying voltage and current to the magnet for thereby magnetizing it, b. cycling means including a rotary assembly which itself includes a relay switch section, and a plurality of bias switching sections, c. means for adjustably varying the voltage applied to the magnet, d. means for adjustably varying the current applied to the magnet, e. stepping means for advancing the rotary assembly through a predetermined cycle, including 1. means responsive to the voltage applied to the magnet for advancing the stepping means, 2. means responsive to current in the magnet for advancing the stepping means, f. means for selectively sensing the voltage and the current applied to the magnet for advancing the stepping means, g. and means responsive to the sensing of the selected one of the voltage and current values and operative for reducing the value of that selected one in successive steps in the cycle to a value near zero, h. and means controlled by the stepping means for reversing the polarity of the voltage applied in successive steps, whereby upon the selected one reaching a value sufficiently low as to be ineffective for producing a successive step in the cycling means and the cycle is thereby terminated.
Claim 2
Dependent Claim
235 words
Apparatus for demagnetizing a magnet which includes necessarily magnetizing it in the steps of demagnetizing it, comprising a. circuit means including the magnet and adapted for connection with an electrical source which includes means for applying voltage and current to the magnet for thereby magnetizing it, b. cycling means including a rotary assembly which itself includes a relay switch section, and a plurality of bias switching sections, c. means for adjustably varying the voltage applied to the magnet, d. means for adjustably varying the current applied to the magnet, e. stepping means for advancing the rotary assembly through a predetermined cycle, including 1. means responsive to the voltage applied to the magnet for advancing the stepping means, 2. means responsive to current in the magnet for advancing the stepping means, f. means for selectively sensing the voltage and the current applied to the magnet for advancing the stepping means, g. and means responsive to the sensing of the selected one of the voltage and current values and operative for reducing the value of that selected one in successive steps in the cycle to a value near zero, h. and means controlled by the stepping means for reversing the polarity of the voltage applied in successive steps, whereby upon the selected one reaching a value sufficiently low as to be ineffective for producing a successive step in the cycling means and the cycle is thereby terminated.
Claim 3
Dependent Claim
117 words
means responsive to current in the magnet for advancing the stepping means, f. means for selectively sensing the voltage and the current applied to the magnet for advancing the stepping means, g. and means responsive to the sensing of the selected one of the voltage and current values and operative for reducing the value of that selected one in successive steps in the cycle to a value near zero, h. and means controlled by the stepping means for reversing the polarity of the voltage applied in successive steps, whereby upon the selected one reaching a value sufficiently low as to be ineffective for producing a successive step in the cycling means and the cycle is thereby terminated.
Claim 4
Dependent Claim
117 words
means responsive to current in the magnet for advancing the stepping means, f. means for selectively sensing the voltage and the current applied to the magnet for advancing the stepping means, g. and means responsive to the sensing of the selected one of the voltage and current values and operative for reducing the value of that selected one in successive steps in the cycle to a value near zero, h. and means controlled by the stepping means for reversing the polarity of the voltage applied in successive steps, whereby upon the selected one reaching a value sufficiently low as to be ineffective for producing a successive step in the cycling means and the cycle is thereby terminated.
Claim 5
Dependent Claim
48 words
A method according to claim 1 and in conjunction with a plurality of magnets of different magnetic characteristics, and including the step of sensing the level of magnetism of the magnets and establishing time intervals between the steps according to the levels of magnetism in the respective magnets.
Claim 6
Dependent Claim
31 words
Apparatus according to claim 1 and including means for sensing the current flow in the magnet at each step operative upon termination of that current flow for initiating the succeeding step.
Claim 7
Dependent Claim
27 words
Apparatus according to claim 1 and including means responsive to a voltage condition as applied to the magnet for terminating each step and initiating a succeeding step.
Claim 8
Dependent Claim
43 words
Apparatus according to claim 1 and including relays for reversing the polarity of the magnetism of the chuck, and means responsive to the level of magnetism of the chuck operative for predetermining the operation of the relays at successive ones of such steps.
Claim 9
Dependent Claim
55 words
Apparatus according to claim 5 and including (relay means for reversing The polarity of the magnet at each step, said relay means including reversing switches and relay coil controlling the switches, and) a pair of secondary relays independently timing the actuation of the reversing relay in opposite directions corresponding to successive ones of said steps.
Claim 10
Dependent Claim
30 words
Apparatus according to claim 6 wherein said secondary relays are responsive to the level of magnetism in the magnet at the corresponding and alternate steps in the cycle of operation.
Claim 11
Dependent Claim
46 words
A plurality of apparatuses according to claim 1 wherein the magnets are of different characteristics, and the relay means for reversing the polarity in the magnets in the several apparatuses are operative for predetermining steps of different characteristics according to the corresponding characteristics of the magnet.
Claim 12
Dependent Claim
22 words
A plurality of apparatuses according to claim 8 wherein the successive steps are of respectively different time intervals in the different apparatuses.
Claim 13
Dependent Claim
28 words
Apparatus according to claim 1 and including means responsive to termination of inductance in the magnet at each step operative for controlling the relays for initiating successive steps.
Claim 14
Dependent Claim
51 words
Apparatus according to claim 1 and including stepping means operable through a cycle of a predetermined number of steps, means for advancing the stepping means through said cycle, and control means responsive to termination of inductance in the magnet at each step for advancing the stepping means through each succeeding step.
Claim 15
Independent Claim
92 words
A method of demagnetizing a magnet, comprising establishing a cycle of operation having a predetermined number of steps, applying a predetermined voltage to the magnet, and thereby applying a corresponding predetermined current thereto, advancing the cycle of operation, selectively sensing the voltage and current for reversing the polarity of the voltage, continuing the cycle and sensing the selective voltage or current at each step of the cycle and reducing the value thereof at each reversal thereof and so reducing it at each step to a value near zero at the final step.
Claim 16
Independent Claim
92 words
A method of demagnetizing a magnet, comprising establishing a cycle of operation having a predetermined number of steps, applying a predetermined voltage to the magnet, and thereby applying a corresponding predetermined current thereto, advancing the cycle of operation, selectively sensing the voltage and current for reversing the polarity of the voltage, continuing the cycle and sensing the selective voltage or current at each step of the cycle and reducing the value thereof at each reversal thereof and so reducing it at each step to a value near zero at the final step.
Claim 17
Dependent Claim
15 words
A method according to claim 12 wherein successive steps are of predetermined different time intervals.
Claim 18
Dependent Claim
16 words
A method according to claim 13 wherein the successive steps are of successively lesser time intervals.
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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) | 1974-05-17 | 1974-11-16 | 1975-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-17 | 1978-11-16 | 1979-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-17 | 1982-11-16 | 1983-05-18 | $7700.00 | Window Closed / Lapsed |