US2072163A - Circuit controlling means - Google Patents
Circuit controlling means Download PDFInfo
- Publication number
- US2072163A US2072163A US751834A US75183434A US2072163A US 2072163 A US2072163 A US 2072163A US 751834 A US751834 A US 751834A US 75183434 A US75183434 A US 75183434A US 2072163 A US2072163 A US 2072163A
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- US
- United States
- Prior art keywords
- circuit
- release
- breaker
- reset
- magnetically actuated
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H71/00—Details of the protective switches or relays covered by groups H01H73/00 - H01H83/00
- H01H71/10—Operating or release mechanisms
- H01H71/12—Automatic release mechanisms with or without manual release
- H01H71/40—Combined electrothermal and electromagnetic mechanisms
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H2300/00—Orthogonal indexing scheme relating to electric switches, relays, selectors or emergency protective devices covered by H01H
- H01H2300/046—Orthogonal indexing scheme relating to electric switches, relays, selectors or emergency protective devices covered by H01H using snap closing mechanisms
Definitions
- cross piece 201 will be moved to the left and the lower part of latch 224 will clear the slot and link I03 will drop, due to the influence of the return spring 226, after which the latch 224, which had been moved counterclockwise as the link I03 moved down returns to its original position with its upper edge resting under the latch surface of the cross piece 201 as shown in Fig. 2, the circuit being remade automatically.
- automatic reset is accomplished, but is delayed until after the thermal element I09 has had suflicient time to cool.
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Breakers (AREA)
Description
March 2, 1937. w. H. FRANK n m. 2,072,163
CIRCUIT CONTROLLING MEANS Filed Nov. 7, 1934 2 Sheets-Sheet 1 INVENTOR. Adm/J. 1M
March 2, 1937. w, FRANK ET AL 2,072,163
cmcun' CONTROLLING mums Filed Nov. 7, 1934 2 Sheets-Sheet 2 INVENTOR. MM JJMJ/ A ORNEY.
' drawings.
Patented Mar. 2, 1937 UNITED STATES PATENT OFFICE CIRCUIT CONTROLLING MEANS WestVIrIIn Application November '1, m4, Serial No. 151334 Claims.
This application relates to circuit controlling means or circuit breakers and particularly to details of construction thereof, and is a continuation in part of our application Serial No. 697,859, illed November 13, 1933, which application in turnis a division of our application Serial No. 614,362, flied May 31, 1932 which became Patent No. 1,952,040 on March 20, 1934.
The principal object of the present invention is to provide, in a circuit breaker, means whereby the circuit breaker will have a delayed release on a prolonged moderate overload, an instantane ous release immediately upon the arising of an excessive overload, and no release upon a momentary moderate overload. In the embodiment disclosed, this object is attained by providing an instantaneously acting magnetic release means, a delayed acting thermal release means overcontrolling the magnetic means, and a magnetic means for overcontrolling the thermal means, the last mentioned magnetic means operating immediately upon the arising of an excessive overload to overcontrol the thermal means and cause instantaneous release.
A further object of the invention is the provision of an automatic release and reset circuit breaker. In the embodiment disclosed, the circuit breaker is reset automatically after release by the influence of gravity.
A further object is the provision of an automatic release and reset circuit breaker constructedto release after a time interval on a prolonged moderate overload, or instantaneously after the arising of an excessive overload, but holding under momentary moderate overloads.
A still further object is the provision of an automatic release and reset circuit breaker having means for delaying the automatic reset operation.
Still further objects are circuit breakers embodying one or more of the features previously outlined, alone or in combination.
For an understanding of the embodiments here disclosed, reference will be had to the appended In these drawings,
Fig. 1 shows a circuit breaker of the automatic release and reset type, and having a quick acting magnetic release means, a slow acting thermal release means for overcontrolling the magnetic release means, and a quick acting magnetic overcontrol for the thermal release means;
Fig. 2, shows in combination with the breaker of Fig. l, a means for delaying automatic reset operation.
Figs. la, and 2a show the modifications in open circuit position following automatic thermal release.
In Fig. 1, there is disclosed a circuit breaker employing a solenoid IOI whose plunger I0! is connected through a link I00 to a breaker contact arm III by a pin and-slot connection at I00. A lug I00 on the link I08 is normally caught under a pivotally mounted cross piece I01, restrained against pivotal movement for release of link I03, by the tip I00 of a thermal holding element I00. Pedestals IIO, III pivotally support the contact arm I00 and the cross piece I01. A hill and valley spring III normally holds contact I00 in position, of! or on contacts III.
The operation of this form of circuit breaker is as follows: When an ordinary or moderate overload occurs, the solenoid IOI is' energized and tends to pull arm Ill upwardly to break the circuit. However, unless the overload has endured sufllciently long to warp element I09 to the right and to release cross link I01, the solenoid cannot eifect circuit breaking since the link I00 is held down by the cross piece I01. After a predetermined interval of overload, the warping element I00 releases the parts for circuit breaking movement by the solenoid.
It will be seen that due to the pin and slot connection I05, the pull of the solenoid gives the link I00 suilicient momentum before contact arm I0 is urged upwardly to make it certain that the solenoid will positively and quickly eflect circuit breaking.
For a heavy overload or short circuit, instantaneous break ought to be provided, and for this purpose we provide quick break means including an armature III, pivoted at II1, to a pedestal IIII. On heavy overload, this armature will be attracted by the solenoid to overcome the action of the spring H9 and force the thermal element I09 to the right and thus allow the circuit breaker to trip instantaneously.
It will be seen that the construction here shown includes parts so arranged that the speed of release will vary with the intensity of the overload, which is a desirable characteristic; and that we provide a belated release for moderate overloads, through thermally responsive means, and an instantaneous release for heavy overloads, through magnetic means. It will also be noted that the same magnet is used for positive break and for the actuation of the instantaneous breaking means, the armature I I6.
To reset the breaker, the plunger I02 and with it the link I08 may be moved down manually,
until lug I06 snaps down past the cross piece I01. Or, if desired, reliance may be placed on gravity to move the plunger I02 and link I03 down until lug I06 snaps past cross piece I01, the parts here functioning to reset the breaker automatically.
If it be found that gravity alone is not sumcient to cause automatic reset, as for example, when the breaker is mounted in any position but the one shown, a spring may be utilized to move the plunger I02 out of the solenoid for automatic spring-caused reset. Where the parts are mounted as shown, however, gravity alone may be relied on to cause automatic reset.
It will be observed that since, in the breaker of Fig. 1, the automatic reset action takes place before the thermal element I00 cools, the right end of the cross piece I01 is moved upwardly out of the path of the tip I08 of the thermal element before the thermal element returns to its original holding position. This characteristic automatically insures proper timing of the operation of the parts and insures the thermal element functioning as a holding means immediately upon its return without further manipulation on the part of the operator.
The breaker of Fig. 1, which is of the auto matic reset type, will reset itself automatically, as soon as the circuit is broken, due to the consequent immediate deenergization of solenoid IOI. Under certain circumstances, as where the overload is a continuing one, the breaker will automatically release and reset in cycles, and these will be so frequent that the contacts at II4 will soon burn out, not having time to cool between cycles. For this reason it is contemplated to provide, as an adjunct to the automatic release and reset breaker here shown, means for delaying the automatic reset action so that the cycles of automatic release and reset will not be so frequent, even when the overload is continued. Such means is shown in Fig. 2 in combination with certain cooperating parts of the breaker of Fig. 1, other parts being omitted for purposes of clarity, and such means, to be known as means for delaying automatic reset operation, will now be described.
The cross piece 201 of Fig. 2, replacing the cross piece I01 of Fig. 1, is mounted to reciprocate between rollers 220 mounted on pedestal III, and is formed with a lug 22I cooperating with the lower end of the pivoted armature II6, whereby the quick acting armature may form a holding means for the cross piece, overcontrolling the delayed action of the thermal element whose tip is received in a groove 222 of the cross piece. The cross piece is formed with a slot 223 formed to cooperate with a latch 224 pivotally mounted on the link I03 and urged by a spring to assume the position shown, with the latch engaging a stop 225 formed on the link I03, the latch, however, being movable, in opposition to the spring, from the position shown, in a counterclockwise direction.
The operation of the automatic release and reset circuit breaker, when equipped with the above described means for delaying automatic reset operation, will now be described. On the arising of an overload of suilicient duration or degree, the thermal element I09 will warp to the right, pulling cross piece 201 with it, whereupon the right end of slot 223 will clear the right end of latch 224. Immediately thereafter, link I03 will move up to break the circuit, after which latch 224, which had been moved. counterclockwise as link I03 moved up, returns to its original position with its lower edge resting upon the upper surface of the cross piece 201. The parts will now be held in circuit breaking position against the influence of the contact arm return spring 226 until thermal element I09 cools and returns to its original position. When this happens, cross piece 201 will be moved to the left and the lower part of latch 224 will clear the slot and link I03 will drop, due to the influence of the return spring 226, after which the latch 224, which had been moved counterclockwise as the link I03 moved down returns to its original position with its upper edge resting under the latch surface of the cross piece 201 as shown in Fig. 2, the circuit being remade automatically. Thus it will be seen that automatic reset is accomplished, but is delayed until after the thermal element I09 has had suflicient time to cool.
It is to be noted that the function of the latch 224 is to prevent strain on the thermal element during movement of the plunger I02. Latch 224 might be omitted and replaced with corresponding projections or lugs on the plunger member I03. However, in this event the thermal element would be strained as the plunger I03 was moved.
One very important consideration of the constructions of this case is the characteristic that the breaker operates with a quick break and quick make switching action. This is accomplished by providing the breaker with a force (the solenoid) tending to open or close the breaker, and a latch (thermal) to prevent the application of such force, the operation being such that when the latch is released the breaker will snap open under the force.
Similarly, the breaker is provided with a force which tends to close the breaker (the spring), and the application of such force is prevented by a latch (the thermal latch) which operates, when released, to permit the force to snap the contacts together for circuit closing.
It will therefore be considered that the constructions of this application possess a common and novel characteristic such as is described in detail in the foregoing.
Now having described the embodiments disclosed herein, reference will be had to the following claims for a determination of the scope of the invention.
What we claim is:
1. Circuit breaker holding and releasing means including magnetically actuated circuit controlled means for causing breaker release, and thermally responsive circuit controlled means for inhibiting the releasing action of the magnetically actuated means, and magnetically actuated circuit controlled means energized on the arising of an excessive circuit abnormality for causing instantaneous release of said thermal means and thereby permitting the first mentioned magnetically actuated circuit controlling means held thereby to cause instantaneous release.
2. Circuit breaker holding and releasing means including magnetically actuated circuit con trolled means positively connected to the contact parts of the breaker to cause positive release or break thereof, and thermally responsive circuit controlled means for inhibiting the releasing action of the magnetically actuated means, and magnetically actuated circuit controlled means energized on the arising of an excessive circuit abnormality for causing instantaneous release of said thermal means and thereby permitting the first mentioned magnetically actuated circuit controlling means held thereby to cause "in stantaneous release.
3. Circuit breaker holding and releasing means including magnetically actuated circuit controlled means for causing breaker release, and thermally responsive circuit controlled means for inhibitins the releasing action or the magnetically actuated means, the thermally responsive means operating, after a predetermined interval of circuit abnormality to permit the circuit breaker releasing action or the magnetically actuated means, and magnetically actuated circuit controlled means energized on the arising of an excessive circuit abnormality for causing instantaneous release of said thermal means and thereby permitting the first mentioned magnetically actuated circuit controlling means held thereby to cause instantaneous release.
4. Circuit breaker holding and releasing means including magnetically actuated circuit controlled means for causing breaker release, and thermally responsive circuit controlled means for inhibiting the releasing actionoi the magnetically actuated means, the thermally responsive means operating, after a predetermined interval of circuit abnormality, to permit the circuit breaker releasing action or the magnetically actuated means, and magnetically actuated circuit controlled means operable on the thermally responsive means instantaneously, but only on an excessive circuit abnormality, to remove the inhibiting action of the thermally responsive means and permit the first mentioned magnetically actuated means to cause breaker release.
5. Circuit breaker holding and releasing means including magnetically actuated circuit controlled means for causing breaker release, and delayedaction circuit controlled means for inhibiting the releasing action oi the magnetically actuated means, the delayed-action means operating, alter a predetermined interval of circuit abnormality, to permit the circuit breaker releasing action of the magnetically actuated means, and magnetically actuated circuit controlled means operable on the delayed-action means instantaneously, but only on an excessive circuit abnormality, to remove the inhibiting action the delwedaction means and permit the first mentioned magnetically actuated means to cause breaker release.
8. Circuit breaker holding and releasing means including circuit controlled releasing means which acquires a releasing tendency immediately upon the arising of a circuit abnormality, and circuit controlled time delay meansior inhibiting the releasing action oi the releasing means. the time delay means operating, after a predetermined interval of continued circuit abnormality, to permit releasing action of the releasing means, and circuit controlled means operable instantaneously, on the arising of an excessive circuit abnormality, to remove the inhibiting action oi the time delay means and permit instantaneous releasing action by the releasing means.
7. An automatic release and reset circuit breaker having circuit breaker holding and releasing means including magnetically actuated circuit controlled means for causing breaker release. and thermally responsive circuit controlled means for inhibiting the releasing action oi the magnetically actuated means. and magnetically actuated circuit controlled means energized on the arising, or an excessive circuit abnormally for circuit controlled means positively connected to a the contact parts or the breaker to insure positive release or break thereoi, and thermally responsive circuit controlled means for inhibiting the releasing action of the magnetically actuated releasing means, and magnetically actuated circuit controlled means energized on the arising oi! an excessive circuit abnormality for causing instantaneous release of said thermal means and thereby permitting the first mentioned magnetically actuated circuit controlling means held thereby to cause instantaneous release, the parts resetting automatically after release.
ll. An automatic release and reset circuit breaker having circuit breaker holding and releasing means including magnetically actuated circuit controlled means for causing breaker release, and thermally responsive circuit controlled means (or inhibiting the releasing action of the magnetically actuated means, the thermally responsive means'operating, after a predetermined interval oi circuit abnormality, to permit the circuit breaker releasing action of the magnetically actuated means, and magnetically actuated circuit controlled means energized on the arising at an excessive circuit abnormality for causing instantaneous release of said thermal means and thereby permitting the first mentioned magnetically actuated circuit controlling means held thereby to cau'se instantaneous release, the parts resetting automatically after release.
10. An automatic release and reset circuit breaker having circuit'breaker holding and releasing means including magnetically actuated circuit controlled means positively connected to the contact parts of the breaker to insure positive release or break thereof, and thermally responsive circuit controlled means for inhibiting the releasing action of the magnetically actuated means. and magnetically actuated circuit controlled means energized on the arising 0! an excessive circuit abnormality for causing instantaneous release of said thermal means and thereby permitting the first mentioned magnetically actuated circuit controlling means held thereby to cause instantaneous release, the parts resetting automatically aiter release.
ll. An automatic release and reset circuit breaker having circuit breaker holding and releasing means including magnetically actuated circuit controlled means for causing breaker release, and delayed-action circuit controlled means for inhibiting the releasing action of the magne'tically actuated means, the delayed-action means operating, alter a predetermined interval of circuit abnormality, to permit the circuit breaker releasing action of the magnetically actuatedmeans;' and magnetically actuated circuit controlled means operable on the delayed-action means instantaneously, but only on an excessive circuit abnormality, to remove the inhibiting action of the delayed-action means and permit the first mentioned magnetically actuated means to cause breaker release. the parts resetting automatically after release.
.12. An automatic release and reset circuit breaker having circuit breaker holding and releasing means including circuit controlled releasing means which acquires a releasing tendency immediately upon the arising 01 a circuit abnormality, and circuit controlled time delay ,means for inhibiting the releasing action of the releasing means, the time delay means operating, after a predetermined interval or continued circuit abnormality, to permit releasing action of the releasing means, and circuit controlled means operable instantaneously, on the arising of an excessive circuit abnormality, to remove the inhibiting action oi the time delay means and permit instantaneous releasing action by the releasing means, the parts resetting automatically after release.
13. In an automatic release and reset circuit breaker, slow acting overload release means and quick acting overload release means, with the latter means overcontrolling the former means, and reset delay means for preventing automatic reset until after a predetermined interval of release.
14. In an automatic release and reset circuit breaker, slow acting overload release means and quick acting overload release means, with the latter means overcontrolling the former means, and reset delay means for preventing automatic reset until aiter a predetermined interval 01' release, and controlled by the slow acting release means so as to permit automatic reset when caused so to do by the delayed return of the slow acting release means from release position.
15. In an automatic release and reset circuit breaker, a slow acting overload release latch and quick acting overload release means operable instantaneously on excessive overloads to release the latch, whereupon the quick acting overload release means, normally held against releasing operation by the latch, operates automatically to open the breaker, and reset delay means for preventing automatic reset until after a predetermined interval of release.
16. An automatic release and reset circuit breaker having holding and quick acting overload release and automatic reset means, a holding and delayed action overload release means overcontrolling the quick acting overload release means, and a quick acting overload actuated means overcontrolling the delayed action overload release means, and reset delay means for preventing automatic reset until after a predetermined interval of release.
17. An automatic release and reset circuit breaker having holding and quick acting overload release and automatic reset means, a holding and delayed action overload release means overcontrolling the quick acting overload release means, and a quick acting overload actuated means overcontrolling the delayed action overload release means and reset delay means for preventing automatic reset until after a predetermined interval of release, and controlled by the delayed action overload release means so as to permit automatic reset of the quick acting means when caused so to do by the return of the delayed action overload release means to holding position.
18. An automatic release and reset circuit breaker having holding and delayed action thermally responsive overload release means and a quick acting magnetlcallly actuated overload actuated means overcontrolling the delayed action overload release means, and reset delay means for preventing automatic reset until after a predetermined interval of release.
19. In an automatic release and reset circuit breaker, a slow returning overload release means, automatic reset means, and -means preventing automatic reset by the automatic reset means until the slow returning overload release means has returned from release position.
20. An automatic release and reset circuit breaker having circuit breaker holding and releasing means including magnetically actuated circuit controlled means for causing breaker release, and thermally responsive circuit controlled means for inhibiting the releasing action oi the magnetically actuated means, and magnetically actuated circuit controlled means energized on the arising of an excessive circuit abnormality for causing instantaneous release of said thermal means and thereby permitting the first mentioned magnetically actuated circuit controlling means held thereby to cause instantaneous release, the parts resetting automatically after release, and reset delay means for preventing automatic reset until after a predetermined interval of release. I
21. An automatic release and reset circuit breaker having circuit breaker holding and releasing means including magnetically actuated circuit controlled means ior causing breaker release, and thermally responsive circuit controlled means for inhibiting the releasing action of the magnetically actuated means, and magnetically actuated circuit controlled means energized on the arising of an excessive circuit abnormality for causing instantaneous release 01' said thermal means and thereby permitting the first mentioned magnetically actuated circuit controlling means held thereby to cause the instaneous release, the parts resetting automatically after release, and reset delay means for preventing automatic reset until after a predetermined interval oi! release and controlled by the thermal means so as to permit automatic reset when caused so to do by the delayed returri of the thermal means from release position.
22. In a circuit interrupter, a movable contact arranged to have a normal tendency to remain in and return to circuit closing position, circuit responsive means arranged to operate, when energized by a circuit abnormality, to move the movable contact to circuit opening position, and when deenergized to permit the movable contact to return to circuit closing position, circuit responsive means normally inhibiting the circuit opening operation of the first means and arranged to operate slowly, when energized by a circuit abnormality, to free the first means so that it may operate for circuit opening, and having a normal tendency to remain in and return to its inhibiting position, and circuit responsive means arranged to operate quickly, when energized by an extraordinary circuit abnormality, to move the second means quickly out of its inhibiting position and thus to free the first means so that it may operate for circuit opening quickly upon the arising oi! an extraordinary circuit abnormality.
23. In a circuit interrupter, a movable contact arranged to have a normal tendency to remain in and return to circuit closing position, circuit responsive means arranged to operate, when energized bya Circuit abnormality, to move the movable contact to circuit opening position, and when deenergized to permit the movable contact to return to circuit closing position, circuit responsive means normally inhibiting the circuit opening operation of the first means and arranged to operate slowly, when energized by a circuit abnormaiity, to free the first means so that it may operate for circuit opening, and having a normal tendency to remain in and return to its inhibiting position, and means for delaying the return of the movable contact to circuit closing position following circuit opening movement thereof until the inhibiting means has returned to inhibiting position.
24. In a circuit interrupter, a movable contact arranged to have a normal tendency to remain in and return to circuit closing position, circuit responsive means arranged to operate, when energized by a circuit abnormality, to move the movable contact to circuit opening position, and when deenergized to permit the movable contact to return to circuit closing position, circuit responsive means normally inhibiting the circuit opening operation of the first means and arranged to operate slowly, when energized by a circuit abnormality, to free the first means so that it may operate for circuit opening, and having a normal tendency to remain in and return to its inhibiting position, and circuit responsive means arranged to operate quickly, when energized by an extraordinary circuit abnormality, to move the second means quickly out of its inhibiting position and thus to free the first means so that it may operate for circuit opening quickly upon the arising of an extraordinary circuit abnormality, and means for delaying the return of the movable contact to circuit closing position following circuit opening movement thereof until the inhibiting means has returned to inhibiting position.
WILLIAM H. FRANK. JOSEPH MEBBING.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US751834A US2072163A (en) | 1934-11-07 | 1934-11-07 | Circuit controlling means |
US99265A US2251703A (en) | 1934-11-07 | 1936-09-03 | Circuit breaker |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US751834A US2072163A (en) | 1934-11-07 | 1934-11-07 | Circuit controlling means |
Publications (1)
Publication Number | Publication Date |
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US2072163A true US2072163A (en) | 1937-03-02 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US751834A Expired - Lifetime US2072163A (en) | 1934-11-07 | 1934-11-07 | Circuit controlling means |
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Country | Link |
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US (1) | US2072163A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2551303A (en) * | 1940-04-23 | 1951-05-01 | Theunissen Francois Jean Marie | Automatic circuit breaker |
US2807689A (en) * | 1951-04-28 | 1957-09-24 | Gen Controls Co | Fluid control valve |
US2937251A (en) * | 1956-03-14 | 1960-05-17 | Westinghouse Electric Corp | Circuit breaker |
-
1934
- 1934-11-07 US US751834A patent/US2072163A/en not_active Expired - Lifetime
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2551303A (en) * | 1940-04-23 | 1951-05-01 | Theunissen Francois Jean Marie | Automatic circuit breaker |
US2551302A (en) * | 1940-04-23 | 1951-05-01 | Theunissen Francois Jean Marie | Automatic circuit breaker |
US2807689A (en) * | 1951-04-28 | 1957-09-24 | Gen Controls Co | Fluid control valve |
US2937251A (en) * | 1956-03-14 | 1960-05-17 | Westinghouse Electric Corp | Circuit breaker |
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