US624895A - Automatic magnetic circuit-breaker - Google Patents
Automatic magnetic circuit-breaker Download PDFInfo
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- US624895A US624895A US624895DA US624895A US 624895 A US624895 A US 624895A US 624895D A US624895D A US 624895DA US 624895 A US624895 A US 624895A
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- circuit
- coil
- core
- breaker
- arm
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- 230000000979 retarding Effects 0.000 description 30
- 230000002159 abnormal effect Effects 0.000 description 10
- 210000002832 Shoulder Anatomy 0.000 description 8
- 238000010586 diagram Methods 0.000 description 8
- 230000000694 effects Effects 0.000 description 8
- 230000036633 rest Effects 0.000 description 4
- OSWPMRLSEDHDFF-UHFFFAOYSA-N Methyl salicylate Chemical compound COC(=O)C1=CC=CC=C1O OSWPMRLSEDHDFF-UHFFFAOYSA-N 0.000 description 2
- 241000658540 Ora Species 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 230000000153 supplemental Effects 0.000 description 2
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Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/08—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current
- H02H3/093—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current with timing means
Definitions
- WITNESSES INVENTOR m: Ncmms PETERS cc, PHOTO-UTH'J. wasmuurow, o, c
- WITNESSES INVENTOR M W )77.
- WW m m uunms PETERS 1:0,, PHOTELLITNV-l.WASNXNGTOM,I10v
- My invention relates to automatic devices that are electrically actuated upon a predetermined condition of flow.
- the object of my invention is to produce an electrically-actuated device which shall operate to open the circuit or perform some other required work upon the occurrence or the continuance during a predetermined space of time of predetermined electrical conditions and also certain improvements in circuit-breakers.
- Figure 1 is -a front View of a specific form of retarding device.
- Fig. 2 is aside view of same.
- Fig. 1 is -a front View of a specific form of retarding device.
- FIG. 3 is a diagram of the paths of the current.
- Fig. 4 is a front view of another form of retarding device employing only one coil for the actuation of the core 14.
- Fig. 5 is a sectional view of the circuit-breaker, showing nately actuated by each of the said two coils.
- each coil is connected by the same binding-post, (shown in Fig. 3 at 44,) while the other end of coil 10 is connected with the contact-plate 18, and the other end of the coil 12 is connected through coil 40 of the electromagnet 30 with the contact-plate 17.-
- the switch-arm 16 which is pivoted at 19 and adapted to contact alternately with the contact-plates 17 and 18, is connected through coil 41 of the electromagnet 30 with the other bind-
- the switch-arm 16 is provided ing-post 45. with shoulders 31 and 32, (shown in Fig. 1,) adapted to engage with the pin 15, which pro jects from the movable core 14.
- the pin 33 which projects from core 14, rests upon the shoulders 35 of thepivoted arm 22 and prevents the further downward movement of the said core 14.
- This ratchet-bar 26 is normally supported and guided by the 7 slotted post 29 and the armature 42, which is attached to the said bar and adapted to be attracted by the electromagnet 30.
- the bar 26 is provided with a series of teeth 36, adapted to engage .with the pawl 24.
- the arm 22 is pivoted at 23 and is provided with shoulders 34 and 35, adapted to engage with the pin 33, which projects from the movable core 14.
- To this arm 22 is pivoted at 25 the pawl 24, adapted to engage upon the upward movement. of the arm 22 with the teeth 36 of bar 26 to lift the bar.
- the coil 40 of the electromagnet 30 is connected in series with coil 12 and plate1'7.
- the other coil 41 of said magnet is connected in series with the switch-arm 16 and binding-post 45, so as to be in series with whichever coil is in circuit, as shown in diagram in Fig. 3.
- the coils 10 and 41 are in the circuit, while coils 12 and are out of the circuit.
- the repeated action of the upward movement of the core is to lift the bar 26 a noteh at a time during the continuance of the flow of current through the device until the bar 26 has accomplished the required range of movement to throw coil 58 into circuit to actuate the circuit-breaker to open the main circuit or accomplish any other required work.
- the coil 10 and the electromagnet lose their energy, so that the movable core 14 and the bar 26 fall to their original positions, as shown in Fig. 1.
- One side of a portion of the movable core maybe flattened, and a suitable piece to engage with said flattened portion of the core maybe attached to one of the jackets to prevent the core from turning.
- Non-magnetic caps or bushings may be used at the ends of the movable core 14 to prevent it from sticking to the fixed cores 20 and 21.
- the set-screw 37 is adapted to engage with the shoulder of pawl 24 as means of its adjustment.
- Additional resistance is introduced at 49, Fig. 3, which may be so varied as to render the device applicable to any desiredyoltage.
- this device is practically the same as that above described, except that upon the movement of the switch-arm 16 away from con tact With contact 18, whereby the coil 10 is cut out of the circuit and so demagnetized, the core 14 falls of its own weight or by spring actuation to its original position.
- a spring maybe used also to assure the return of arm 22 upon the fall of the movable core.
- FIG. 5 A specific form of the circuit breaker, which is indicated diagrammatically in Fig. 3, is shown in Fig. 5, in which 50 is the usual solenoid-coil, adapted to operate the movablev core 51. Attached to the lower end of this core is a circular disk or plate 52, provided with grooves adapted to receive the sides of the frame or stirrup 53 to guide the said movable core. Upon the inner sides of this stirrup are projections 54, adapted to support the washer or plate 55, which surrounds the core 51 and through which the core is free to move. Upon the lower side of this plate 55 and properly insulated therefrom are two contact points or ter minals 56 and 57, connected, respectively, one with coil 50 and the other with the bindingpost 44, as shown in Fig.
- the second binding-post 45 being connected with the opposite side of the circuit containing coil 50.
- the coil 50 is in series with the main circuit and main switch 61.
- the coil 58 which may be located within coil 50 and adapted also to actuate core-51., is connected between coil 50 and contact 59 and is so wound that a relatively small current will energize it to actuate the core 51 to open switch 61 and is of such resistance as to employ only a suitable amount of current upon the bridging of contacts 59 and 60.
- the contact 60 is connected with the opposite side of the main circuit.
- the coil 50 Upon a predetermined above-normal flow of current the coil 50 will be energized to draw the movable core 51 upward, causing the plate 52 to bridge the contacts 56 and 57 to bring the retarding device into circuit.
- the bar 26 Upon this condition continuing the bar 26 will be operated to move upward until it bridges the contacts 59 and 60, thereby throwing the coil 58 into circuit to energize it to actuate core 51 to operate switch 61 to
- the movable core 51 will fall away from the contacts 56 and 57 and so cut the retarding device out of circuit.
- the core 51 Upon the occurrence of a predetermined greater overflow of current through the coil 50 or a short-circuit the core 51 will be actuated to rise instantly against the weight of the plate 55 to actuate the switch 61 to open the circuit.
- a normally open-circuited coil having a movable core and adapted when brought into circuit to actuate the mov able core to effect the opening of the main switch of the circuit-breaker, a retarding device adapted after a predetermined time dur in gwhich it is in circuit, to close the circuit of the normally open-circuited coil, and means for bringing into circuit upon the occurrence of a predetermined overflow said retarding device and formaintaining the same in circuit during the continuance of said overflow.
- a pivoted arm provided with a pawl pivoted thereto, the said arm adapted to be actuated by the armature or core, a ratchetbar adapted to engage with the pawl on the pivoted arm and to be lifted by it upon each alternate movement of the pivoted arm and a retaining-magnet adapted to hold the ratchetbar in its advanced position after the disengagement of the pawl.
- an automatic magnetic circuit breaker the combination of stationary and movable contacts, two solenoid-coils, a core movable in each coil, the first coil adapted upon a predetermined overflow of current through it to actuate its movable core to close and maintain closed, during the continuance of said overflow,the circuit of a retarding device,'but upon the occurrence of a predetermined greater overflow or short-circuit to actuate said movable core instantly to open the main switch, the second coil normally open-circuited but adapted to be drawn into circuit as hereinafter described, a retarding device normally open-circuited but adapted after a predetermined time during which it is maintained in circuit to close or bring intocircuit the normally open-circuited coil to actuate its movable core to open the switch.
- a movable piece suitably guided and supported and carrying terminals adapted to be bridged upon the movement of the core or armature and adapted to permit of the full movement of the core or armature only upon the occurrence of a magnetic pull sufficient to overcome the additional restraint imposed by said movable piece.
Landscapes
- Breakers (AREA)
Description
No. 624,895. Patented May 9, I899. w. m. SCOTT.
AUTOMATIC MAGNETIC CIRCUIT BREAKER.
(Application filed July 2s, 1897.)
(No Model.) v 3 Sheets8he et I.
WITNESSES: INVENTOR m: Ncmms PETERS cc, PHOTO-UTH'J. wasmuurow, o, c
Patented May 9, I899. W. M. SCOTT.
AUTOMATIC'MAGNETIC CIRCUIT BREAKER.
(Application filed July 28, 18 97.)
3 Sheets$heet 2.
(No Model.)
INVENTOR WITNESSES:
ATTORNEY.
No. 624,895. Patented May 9, I899;
w. M. SCOTT.
' AUTOMATIC MAGNETIC CIRCUIT BREAKER.
(Application filed July 28, 1897.)
(No Model.) 3 Sheets-Sheet 3.
WITNESSES: INVENTOR M W )77. WW m m: uunms PETERS 1:0,, PHOTELLITNV-l.WASNXNGTOM,I10v
UNITED STATES PATENT OFFICE.
WILLIAM M. SCOTT, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO THE CUTTER ELECTRICAL AND MANUFACTURING COMPANY, OF
N EW JERSEY.
AUTOMATIC MAGNETIC CIRCUIT-BREAKER.
sPEoIFicArIoN forming part of Letters Patent No. 624,895, dated May 9, 1899.
Application filed July 28, 1897. Serial No, 646 16'7. (N model.)
To all whom it may concern:
Be it known that I, \VILLIAM M. SCOTT, a citizen of the United States, residing at Philadelphia, county of Philadelphia, and State of Pennsylvania, have invented a new and useful Automatic Magnetic Circuit-Breaker, of which the following is a specification.
My invention relates to automatic devices that are electrically actuated upon a predetermined condition of flow.
The object of my invention is to produce an electrically-actuated device which shall operate to open the circuit or perform some other required work upon the occurrence or the continuance during a predetermined space of time of predetermined electrical conditions and also certain improvements in circuit-breakers.
In many cases it is desirable to have a circuit-breaker that will not open instantly upon a certain predetermined overflow of current, but will only open upon the continuance of that overflow during a certain space of time and which will instantly open upon a sided before the supplemental high-resistance coil shall have been brought into circuit the retarding device will be out out of circuit and its different parts will assume their normal positions.
In the accompanying drawings, Figure 1 is -a front View of a specific form of retarding device. Fig. 2 is aside view of same. Fig.
3 is a diagram of the paths of the current. Fig. 4 is a front view of another form of retarding device employing only one coil for the actuation of the core 14. Fig. 5 is a sectional view of the circuit-breaker, showing nately actuated by each of the said two coils.
One end of each coil is connected by the same binding-post, (shown in Fig. 3 at 44,) while the other end of coil 10 is connected with the contact-plate 18, and the other end of the coil 12 is connected through coil 40 of the electromagnet 30 with the contact-plate 17.-
The switch-arm 16, which is pivoted at 19 and adapted to contact alternately with the contact-plates 17 and 18, is connected through coil 41 of the electromagnet 30 with the other bind- The switch-arm 16 is provided ing-post 45. with shoulders 31 and 32, (shown in Fig. 1,) adapted to engage with the pin 15, which pro jects from the movable core 14. Until a flow of current through the device the movable core 14 rests in its lowest position, the pin 33, which projects from core 14, rests upon the shoulders 35 of thepivoted arm 22 and prevents the further downward movement of the said core 14. In this condition of my device the current will then pass from one binding-post through coil 41, the switch-arm 16, and the plate 18, with which the switch-arm is in contact,and thence through the coil 10 to the other binding-post. Upon a flow of current through the device the coil 1.0 is energized to draw the movable core 14 upward into it, carrying the switch-arm 16 with it away from contact with plate 18 and to contact with plate 17, thereby throwing the coil 10 out of circuit and the coil 12 into circuit. The effect of this is to demagnetize the formerand magnetize the latter to draw the movable core back to its original position. This operation is repeated during the continuance of a flow of current through the device or until the required movement of the ratchet-bar 26. This ratchet-bar 26 is normally supported and guided by the 7 slotted post 29 and the armature 42, which is attached to the said bar and adapted to be attracted by the electromagnet 30. The bar 26 is provided with a series of teeth 36, adapted to engage .with the pawl 24.
The arm 22 is pivoted at 23 and is provided with shoulders 34 and 35, adapted to engage with the pin 33, which projects from the movable core 14. To this arm 22 is pivoted at 25 the pawl 24, adapted to engage upon the upward movement. of the arm 22 with the teeth 36 of bar 26 to lift the bar. The coil 40 of the electromagnet 30 is connected in series with coil 12 and plate1'7. The other coil 41 of said magnet is connected in series with the switch-arm 16 and binding-post 45, so as to be in series with whichever coil is in circuit, as shown in diagram in Fig. 3. Upon the occurrence of a flow of current through the device the coils 10 and 41 are in the circuit, while coils 12 and are out of the circuit. The effect of this is to draw the core upward into the coil 10, as above described, carrying with it the arm 22 and pawl 24, which lifts the bar 26, at the same time the switcharm 16 is actuated to throw coil 1.0 out of circuit and coils 12 and 40 into circuit, the effect of which is to energize coil 12 to draw the core back to its original position, and coils 40 and 41. both being in circuit the electromagnet 30 is energized to attract the armature 42 and prevent the bar 26 from falling upon being released by the pawl 24. The repeated action of the upward movement of the core is to lift the bar 26 a noteh at a time during the continuance of the flow of current through the device until the bar 26 has accomplished the required range of movement to throw coil 58 into circuit to actuate the circuit-breaker to open the main circuit or accomplish any other required work. In case of the abatement or the discontinuance of the flow of current through the device the coil 10 and the electromagnet lose their energy, so that the movable core 14 and the bar 26 fall to their original positions, as shown in Fig. 1.
During the continuance of flow of current through the device the operation of the device, while alternately shifting the current from one path to the other, does not materially interfere with the total flow of current.
One side of a portion of the movable core maybe flattened, and a suitable piece to engage with said flattened portion of the core maybe attached to one of the jackets to prevent the core from turning.
Non-magnetic caps or bushings may be used at the ends of the movable core 14 to prevent it from sticking to the fixed cores 20 and 21.
The set-screw 37 is adapted to engage with the shoulder of pawl 24 as means of its adjustment.
Additional resistance is introduced at 49, Fig. 3, which may be so varied as to render the device applicable to any desiredyoltage.
lVhile I have described in detail the device as shown in Figs. 1 and 2 and diagram in Fig. 3, I may modify the same in various ways and still retain the important features already disclosed. For instance, I do not wish to be confined to the arrangement of the coils one above the other adapted to actuate the same movable core. The coils maybe side by side, with the movable core of each actuating the same oscillating or pivoted arm, or, as shown in Fig. 4, I may dispense with the coil 12, having a movable core adapted to be actuated in one direction by the coil 10 and in the other direction by gravity. In this case a diagram similar to that of Fig. 3 .would show the coil 12 eliminated and the binding-post 44 connected directly to coil 40. The operation of this device is practically the same as that above described, except that upon the movement of the switch-arm 16 away from con tact With contact 18, whereby the coil 10 is cut out of the circuit and so demagnetized, the core 14 falls of its own weight or by spring actuation to its original position. A spring maybe used also to assure the return of arm 22 upon the fall of the movable core.
A specific form of the circuit breaker, which is indicated diagrammatically in Fig. 3, is shown in Fig. 5, in which 50 is the usual solenoid-coil, adapted to operate the movablev core 51. Attached to the lower end of this core is a circular disk or plate 52, provided with grooves adapted to receive the sides of the frame or stirrup 53 to guide the said movable core. Upon the inner sides of this stirrup are projections 54, adapted to support the washer or plate 55, which surrounds the core 51 and through which the core is free to move. Upon the lower side of this plate 55 and properly insulated therefrom are two contact points or ter minals 56 and 57, connected, respectively, one with coil 50 and the other with the bindingpost 44, as shown in Fig. 3, the second binding-post 45 being connected with the opposite side of the circuit containing coil 50. The coil 50 is in series with the main circuit and main switch 61. The coil 58, which may be located within coil 50 and adapted also to actuate core-51., is connected between coil 50 and contact 59 and is so wound that a relatively small current will energize it to actuate the core 51 to open switch 61 and is of such resistance as to employ only a suitable amount of current upon the bridging of contacts 59 and 60. The contact 60 is connected with the opposite side of the main circuit. Upon a predetermined above-normal flow of current the coil 50 will be energized to draw the movable core 51 upward, causing the plate 52 to bridge the contacts 56 and 57 to bring the retarding device into circuit. Upon this condition continuing the bar 26 will be operated to move upward until it bridges the contacts 59 and 60, thereby throwing the coil 58 into circuit to energize it to actuate core 51 to operate switch 61 to open the circuit.
In case the abnormal flow should subside before the ratchet-bar 26 shall have reached the contacts 59 and 60 the movable core 51 will fall away from the contacts 56 and 57 and so cut the retarding device out of circuit. Upon the occurrence of a predetermined greater overflow of current through the coil 50 or a short-circuit the core 51 will be actuated to rise instantly against the weight of the plate 55 to actuate the switch 61 to open the circuit. The operation of the complete device, therefore, is that an abnormal flow not reaching a certain predetermined maximum will only cause the main switch to open upon the continuance of the said overflow during the predetermined space of time required to operate the retarding device to throw coil 58 into circuit; but upon the occurrence of the predetermined maximum flow ora short=circuit the core 51 will be instantly actuated to operate the main switch 61 to open the circuit.
In the drawings and above specification I have described a specific form of retarding device which has an oscillating movement and applies that movement to the actuation of a ratchet-bar to close the circuit of the highresistance coil. It is obvious, however, that other forms of retarding device may be used for this purpose with equal efficiency, and while I believe there is patentable subjectmatter in this specific device described by me and have made claims therefor I do not wish in my broad claims to be confined to any specific form of retarding device.
WVhat I claim as my invention, and desire to secure by Letters Patent, is'
1. The combination of automatic magnetic means for breaking the circuit upon the occurrence of a predetermined abnormal flow, normally open-circuited automatic magnetic means for breaking the circuit upon the occurrence of a less abnormal flow and automatic magnetic means for bringing into cir cuit the said normally open-circuited means upon the continuance of said less abnormal flow during a given space of time.
2. In an automatic magnetic circuit-breaker the combination of separable cooperative con-.
tacts, two coils, relatively, one of low and the other of high resistance, means adapted to be actuated by each coil to cause the separation of the said contacts, the low-resistance coil normally in circuit and the high-resistance coil normally out of circuit, and means for bringing into circuit the normally open-circuited coil, substantially as described.
3. In an automatic magnetic circuitbreak'er the combination of fixed and movable contacts, two coils and a core or armature adapted to be actuated by each to cause the actuation of the movable contacts, one coil normally in circuit and one coil normally open-circuited, a retarding device adapted after a predetermined time, during which it is in circuit, to
close the circuit of the normally open-circuited coil and means for bringing into and maintaining in circuit upon and during a predetermined overflow said retarding device. I
4. In combination with an automatic magnetic circuit-breaker a normally open-circuited coil having a movable core and adapted when brought into circuit to actuate the mov able core to effect the opening of the main switch of the circuit-breaker, a retarding device adapted after a predetermined time dur in gwhich it is in circuit, to close the circuit of the normally open-circuited coil, and means for bringing into circuit upon the occurrence of a predetermined overflow said retarding device and formaintaining the same in circuit during the continuance of said overflow.
5. In combination with an electrically-actuated device having an oscillating armature or core, a pivoted arm provided with a pawl pivoted thereto, the said arm adapted to be actuated by the armature or core, a ratchetbar adapted to engage with the pawl on the pivoted arm and to be lifted by it upon each alternate movement of the pivoted arm and a retaining-magnet adapted to hold the ratchetbar in its advanced position after the disengagement of the pawl.
6. In an automatic magnetic circuit breaker the combination of stationary and movable contacts, two solenoid-coils, a core movable in each coil, the first coil adapted upon a predetermined overflow of current through it to actuate its movable core to close and maintain closed, during the continuance of said overflow,the circuit of a retarding device,'but upon the occurrence of a predetermined greater overflow or short-circuit to actuate said movable core instantly to open the main switch, the second coil normally open-circuited but adapted to be drawn into circuit as hereinafter described, a retarding device normally open-circuited but adapted after a predetermined time during which it is maintained in circuit to close or bring intocircuit the normally open-circuited coil to actuate its movable core to open the switch.
' 7. In combination with an automatic magnetic circuit-breaker employing a solenoidcoil orelectromagnet and a core or armature actuated thereby, a movable piece suitably guided and supported and carrying terminals adapted to be bridged upon the movement of the core or armature and adapted to permit of the full movement of the core or armature only upon the occurrence of a magnetic pull sufficient to overcome the additional restraint imposed by said movable piece.
WM. M. SCOTT.
Witnesses:
JNo. STOKES ADAMS, E. F. GRACE.
Publications (1)
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US624895A true US624895A (en) | 1899-05-09 |
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US624895D Expired - Lifetime US624895A (en) | Automatic magnetic circuit-breaker |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2445110A (en) * | 1944-11-20 | 1948-07-13 | Jack & Heintz Prec Ind Inc | Overload relay having an instantaneous primary movement and a delayed secondary movement |
-
0
- US US624895D patent/US624895A/en not_active Expired - Lifetime
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2445110A (en) * | 1944-11-20 | 1948-07-13 | Jack & Heintz Prec Ind Inc | Overload relay having an instantaneous primary movement and a delayed secondary movement |
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