US2468498A - Automatic reclosing circuit breaker - Google Patents

Description

April26, 1949.

Filed Sept. 2,1945

W. D. KYLE, JR., ETAL AUTOMATIC RECLOSING CIRCUIT BREAKER 5 Sheets-Sheet l INVENTORS. Mum, 0. Km: (/P.

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-ATfOFA/EK April 26, 1949.

W. D. KYLE, JR, ET AL AUTOMATIC RECLDSING CIRCUIT BREAKER 5 sheets sheet 2 Filed Sept. 2, 1943 5111/ 17111111111 11l41Ill/114111:

INVENTORS. W/[l/AM 0. Km (/4? By 0121 Jaw/mm April 26, 1949. w. o. KYLE, JR, ETAL 2,468,498

AUTOMATIC RECLOSING CIRCUIT BREAKER Filed Sept. 2, 1943- 5 Sheets-Sheet 3 INVENTORS, Mum/0.1m: MP. By 64M Jam/04m ATTORNEY.

April 26,1949. w. D. KYLE, JR., ET AL 2,468,498

AUTOMATIC RECLOSING CIRCUIT BREAKER Filed Sept. 2,1943 5 Sheets-Sheet 4 14 INVENTORS.

April 26, 1949.

W. D. KYLE, JR., ETAL AUTOMATIC RECLOSING CIRCUIT BREAKER 5 Sheets$heet 5 Filed Sept. 2, 1943 INVENTORS. Mum/4 D. KY1: 1/12 64,91 Jew/mm Patented Apr. 26, 1949 AUTOMATIC RECLOSING CIRCUIT BREAK William'D. Kyle, Jr., Milwaukee, and Carl Schindler, Wauwatosa, Wis., assignors to Line Material Company, a corporation of Delaware Application September 2, 1943, Serial No. 500,918

7' Claims. (01. 175-294) This invention relates to automatic reclosing circuit breakers and is an improvement of the invention disclosed in our copending application Serial No. 396,850 filed June 6, 1941, for Automatic reclosing circuit breakers.

This invention has all of the objects specifically set forth in our copending application, a few of which may be summarized as follows:

To provide an automatic repeating circuit breaker which will respond to an overload and will again close after a predetermined interval, which will lock out after a predetermined number of operations if they occur in sufficiently rapid succession, but which will reset itself for the full number of operations if they occur at sufliciently spaced intervals, which is provided with means for permanently biasing it towards lockout position without depending upon the integrity of a ratchet or pawl, which may be manually tripped and manually reset, which is free for automatic operation while it is being manually reset, which may be automatically opened upon rise of temperature above a predetermined point, which is oil immersed and mounted in a metal can or housing open only at the top, which is suspended from the top or cover of the can and can be readily removed without disturbing the can, which is trip free, which has hydraulic time delay and cumulative lock-out means, and which will lock out when subjected to a low electrical overload not sufiicient to fully operate the circuit breaker but which would cause continued repeated operations, and which will lock out after a single extremely violent overload sufficient to cause an excessive evolution of gas.

In addition to the above, it is a particular object of this invention to provide a circuit breaker which may be readily coordinated with fuses which are used in the distribution system, so that there is a definite predetermined relation between the time current characteristics of the circuit breaker and the fuses.

Specifically, objects of this invention are to provide a circuit breaker which has a predetermined time current characteristic for its first operation and a difierent time current character istic for successive operations provided they occur within a sufiiciently short time after the first operation, and which is arranged to change back to its first time current characteristic if the successive operations do not occur within a sufiiciently short interval of time after the first operation;

In greater detail, objects of this invention are to provide a circuit breaker which will open for 2 a predetermined current valueior its first operation but which will require a higher current value for a successive operation or operations provided thcy occur within a predetermined interval of time, and which will reset itself for the lower current value if the successive operations do not occur with suiiicient rapidity, and which will reset itself for the lower current value if the total number of operations even if they occur in quick succession is less than the predetermined selected number for which the circuit breaker will lock itself out.

Embodiments of the invention are shown in the accompanying drawings, in which:

Figure 1 is a vertical sectional view, with parts broken away, showing the circuit breaker in closed position, such view corresponding to a section on the line |l of Figure 4.

Figure 2 is a sectional view on the line 2-2 of Figure 1.

Figure 3 is a wiring diagram showing one form of bridging circuit for the actuating or magnet coil and showing diagrammatically parts of the circuit breaker.

Figure 4 is a sectional view on the line 4-l of Figure 1.

Figure 5 is a sectional view on the line 55 of Figure 4.-

Figure 6 is a view of the top plate and associated parts with the upper portion of the apparatus sectioned ofi.

Figure 7 is a sectional detail of the thermostatic tripping means, such view being taken on the section line 1-1 of Figure 6.

Figure 8 is a sectional detail of the time delay means for delaying the closing of the main switch means.

Figure 9 is a sectional view on the line 99 of Figure 5.

Figure 10 is a sectional view on the line l0l0 of Figure 4.

Figure 11 is a sectional view on the line I |il of Figure 1.

Figure 12 is a detail showing a portion of the manual trip and reset mechanism.

Figure 13 is a fragmentary detail, partly in section, drawn to an enlarged scale showing the means for altering the action of the overload means, such view showing the parts in the position they assume prior to initial operation of the circuit breaker.

Figure 14 is a view corresponding to Figure -13 showing the position of the parts after the circuit breaker has moved to open position.

some Figure 15 is a view of a further form of bridging circuit.

The circuit breaker is oil immersed and is mounted within the 011 containing metal can I which is provided with a removable top 2 removably held to the can in any suitable manner. A convenient way of attaching the top to the can is by means of a plurality of bolts 3 which are pivotally mounted between spaced ears 4 carried by the can and which are provided with wing nuts 5. The wing nuts are adapted to bear against L- shaped clamping plates 6 whose downwardly extending portion is adapted to rest upon the upper face of the ears 4, a suitable lug I being provided on each of the ears to prevent the clamping plates 6 from sliding off the upper surface of the ears 4. A suitable sealing gasket is positioned between the flanged upper end of the can and the annular recessed portion of the cover 2, as shown most clearly in Figure 1.

Any suitable attaching means as indicated at 8 and 9 are provided on the can so that the can may be attached to a pole or other suitable support.

The cap or cover 2 is provided with a line and load terminal indicated respectively at I and II, and these terminals are carried by insulating bushings I2, I2, see Figure 3.

The automatic reclosing circuit breaker is suspended in its entirety from the metal cover 2. For example, the metal cover may be provided with a plurality of downwardly extending insulating posts I 3 which are secured at their upper ends to the metal cover and at their lower ends to the circuit breaker.

The electromagnetic coil or solenoid is indicated at I4 and may be wound around an insulating, centrally located tube I5.

A non-magnetic operating rod l6 for the circuit breaker extends upwardly centrally of the insulating tube I and on this rod a plunger II formed of magnetic material is freely slidable. The plunger I! or armature is provided with an enlarged or shouldered lower portion I 3 which acts as a piston when passing into the cylindrical chamber I 9 formed in the collar or block 20 for a purpose hereinafter to appear.

The operating rod I6 of the circuit breaker rigidly carries a. spider like stop 2| which loosely fits within the tube I5 and serves as an abutment against which the upper end of the magnetic plunger I! strikes when the coil I4 is energized by an overload current. When this occurs, the plunger I! is suddenly drawn upwardly into the coil and strikes the abutment 2 I, carrying the rod I6 upwardly with a quick motion.

The lower end of the rod I6 is rigidly secured to a conducting cross-head 22, see Figures 1 and 2. The cross-head 22 carries a pair of contact rods 23 which are rigidly attached at their lower ends to contact sleeves 24. The contact sleeves 24 normally engage the stationary contact pins 25, see Figure 2. These stationary contacts or contact pins 25 are connected as shown diagrammatically in Figure 3 and are preferably longitudinally split as indicated in Figure 2 to give them resiliency.

It is to be noted particularly from reference to Figure 2 that the contact pins 25 form stops for arresting the movable contact members 23, 24 at a predetermined position and correspondingly arrest the magnetic plunger I! at a predetermined position with reference to the coil I4. The current carrying contact portions are between the pins 25 and the sleeves 24, the ends of the pins 25 and the lower ends of the conducting rods 23 merely constituting stops. The arcing contacts indicated at 26 in Figure 1 may be carried by leaf springs 21 and may engage the outer surface of the sleeves 24 so that any pitting due to arcing is confined to the outer portion of the sleeves and does not affect the normal current carrying surfaces which are internally of the sleeves.

It is also preferable to provide insulating bar riers 28 which extend upwardly between the Sta-- tionary contacts and also extend outwardly beneath the stationary contacts. The stationary contacts are carried by a lower insulating plate 29 and an insulating sleeve 3| is positioned between the plate 23 and the shouldered member 20, as shown in Figure l. The plate 23 is preferably provided with an aperture 30 through which oil may pass upwardly and with a flap valve 30' which is adapted to normally remain in closed position and to prevent downward flow of oil outwardly from the casing or cylindrical member 3I.

Referring to Figures 1 and 4, it will be seen that a rock shaft 32 extends transversely of the cover or cap 2. A rocking sleeve 33 is loosely mounted on the rock shaft and is provided with a relatively long arm 34, see Figures 1 and 4, and a relatively shorter arm 35, see Figure 4, which constitute, together with the sleeve 33, a unitary member freely rockable upon the shaft 32. The relatively long arm 34 is connected by means of a pair of insulating links 36 with the upper end of the operating rod ii of the circuit breaker, as shown most clearly in Figure 1. Thus when the circuit breaker is driven to open position upon the occurrence of an overload, the arm 34, and consequently the arm 35, are rocked upwardly. The arm 35, as shown in Figure 8, is connected by means of an insulating link 3! with a plunger 38 which is normally positioned within the relatively large portion 39 of a cylinder 40.

The cylinder is provided with a relatively smaller upper bore 4| within which a spider like guiding member 42 of the plunger 38 freely rides. When the arms 34 and 35 are rocked upwardly, the plunger 38 passes from the relatively large bore 39 into the relatively small bore 4|. It is freely drawn upwardly in the relatively small bore 4! as the sprin pressed valve 43 yields and allows oil to pass downwardly through the apertures in the piston 33 into the space below the plunger or piston, thus allowing the circuit breaker to open with a very quick stroke.

After the circuit breaker has opened, it cannot immediately close for there is a time delay produced by the downward travel of the plunger 33 through the relatively small bore 4I the oil leaking out around the side of the plunger and retarding the downward motion of the circuit breaker. However, as the circuit breaker approaches closed position, the plunger 38 passes out of the small bore into the large bore and the final portion of the closin stroke of the circuit breaker is executed with a quick motion.

The purpose of providing a time delay for the closing stroke of the circuit breaker is to allow an interval of time to elapse before the circuit breaker is closed after it has once been quickly opened on overload so that if the fault is transient and is cleared up immediately, the circuit breaker will remain closed. However, if the fault persists the circuit breaker will execute another quick opening stroke.

Means are provided for locking the circuit breaker in open position after a predetermined number of rapidly succeedin operations. This is accomplished by providing a tripping means actuated by oil pumped by the circuit breaker upon operation of the circuit breaker and is partially illustrated in Figure 1. It is to be noted that the circuit breaker is oil immersed, the oil level being indicated by the reference character 44. It is apparent, therefore, that when the head or piston like portion |8 of the circuit breaker enters the cylinder like portion l9, oil is pumped past the check valve into the cylinder 46 beneath the piston 41 and causes the piston to rise a predetermined distance. Repeated operations of the circuit breaker cause predetermined quantities of oil to be pumped beneath the piston 41 and cause the piston to 'rise for each operation of the circuit breaker. This construction also provides a hydraulic cushion for the plunger I! and materially reduces wear.

It is to be noted from reference to Figure 1 that the piston portion l8 of the plunger I! may freely pass downwardly as a check valve 48 is provided which allows oil to enter the cylinder like portion |9 upon downward stroke of the plunger l'l.

It is apparent that after a predetermined number of operations, the piston 41 will project. its rigidly carried pin 49 upwardly through the aperture 50 and will engage the trip latch 5| and thus raise the trip latch. The raising of the trip latch 5| releases the lock-out mechanism and locks the circuit breaker in open position in a manner hereinafter to be described. It is desirable to have this lock-out of the circuit breaker occur not only when there has been a predetermined number of operations of the circuit breaker but also only when these operations occur in rapid succession.

The above stated result is accomplished by providing an adjustable leak from the cylinder 46 at a point beneath the piston 41. As shown in Figure 11 which is an enlarged view of the lower portion of the cylinder 46, it will be seen that a leak passage has been provided which is controlled by an adjustable needle valve 52 so as to regulate the rate at which oil will leak from beneath the piston 41. Suppose, for example, that less than the predetermined number of quickly succeeding operations has occurred. The piston or tripping plunger 41 will settle downwardly as the oil flows outwardly from beneath the piston past the needle valve 52 and will finally come to rest at the bottom part of its stroke, as shown in Figure 1, thus resetting the piston or tripping plunger 4! in its initial position.

This feature is of particular importance for if the circuit breaker performs one or two operations where it had been designed for a three operation lock-out, the circuit breaker will still have its full number of times for a sequential rapid operation in the event any subsequent fault occurs.

Referring to Figures 4, 5 and 6, it will be seen that the latching lever 5| normally engages a metal plate 53 which is rigidly carried by an insulating lever 54. The insulating lever 54 is rigidly bolted to a metal lever 55 which is integral with a sleeve 56. A second lever 5'! is also rigid with the sleeve 55 and is spring urged in a counterclockwise direction by means of the spring 58, one end of which is fastened to the lever 51 and the other end of which is fastened to the metal cap 2, see Figure 1. It will be seen, therefore, that the latch lever 54 is permanently biased towards its uppermost position, which will be shown as the description proceeds to be the lockout position for the circuit breaker. The lever 55, as will be seen from Figures 1 and 4, is provided with a head or pin 59 which is directly beneath the lever 34 which is attached by means of links 36 to the operating rod l6 of the circuit breaker. Therefore, it is apparent that when the trip latch 5| is released, the circuit breaker will be locked open as the spring 58 will cause the lever 55 with the projection 55 to rock in a counterclockwise direction, see Figure 1, and will thus hold the circuit breaker locked open. The circuit breaker will thus be permanently biased towards open position when it is locked out and will not be dependent upon any pawl or any other type of latch of this order which might jar loose and allow the circuit breaker to drop to closed position.

It sometimes happens that sufficient current is passed through the coil to abnormally heat the coil with consequent damage to the apparatus without causing operation of the circuit breaker.

This is prevented by thermal means responsive to the temperature within the tank I for operating the trip latch 5|. As may be seen from reference to Figures 4, 6 and 7, a bimetallic folded strip 66 is carried by the upper plate 6|. It is to be noted from reference to Figure 1 that a lower plate 6| is provided. These upper and lower plates 6| and 6| may be of insulation as shown or may be of metal if so desired. The bimetallic strip 60 has its free end positioned beneath the trip latch 5| so that when the bimetallic strip 66 opens up as the coil becomes abnormally heated. it will raise the trip latch 5| and release the trip lever 54, thereby causing a quick opening of the circuit breaker under the influence of the spring 58 and will lock the circuit breaker in open position.

Manual means are also provided for opening the circuit breaker with a quick opening stroke. The manual operating means consists of an eyeleted lever 62, see Figures 4 and 12, which is positioned within a hood 63 integral with the cap 2. The hood is open at its lower side and is provided with a cut out 64 so that the hook of a switch stick may be inserted in the eye of the lever 62, and the lever may be drawn downwardly to cause a quick opening of the circuit breaker in a manner hereinafter to appear, or to move the lever upwardly back to the position shown in Figure 12 to reset the circuit breaker.

The lever 62 is rigidly attached to the shaft 32 and the shaft 32 rigidly carries a reset lever 65 and an eccentric 66, see Figures 4 and 10. The eccentric 66 is most clearly shown in Figures 5 and Ill. The sleeve 56, see Figures 4 and 5, is loosely mounted on the eccentric 66 and is free to rock about such eccentric independently of any action of the eccentric. However, when the lever 62 is pulled downwardly, the eccentric 66 draws the lever 54 upwardly in a slanting direction towards the left as viewed in Figure 5 and thus withdraws the latch plate 53 from the latch lever 5|. The spring 58 is now free to act and causes a quick counterclockwise stroke of the lever 55 whose pin or projection 59, see Figures 1 and 4. strikes the lever 34 and opens the circuit breaker with a quick opening stroke. The circuit breaker will now be permanently locked open until it is manually reset.

The resetting is accomplished through the medium of the lever 62. the shaft 32, and the resetting lever 65, see Figures 4, 9 and 10. The reset lever 65 is positioned above a pin or projection 61 rigid with the latching lever 54, as shown most clearly in Figure 9, the projection 61 being shown in dotted lines in Figure 4. It is clear that when the lever 62 is rocked upwardly back to its position shown in Figure 12, the reset lever 65 will engage the pin 61 and will force the latching lever 54 downwardly against the action of the spring 58 to its normal position as shown in Figure 1, thus resetting the circuit breaker. The circuit breaker will thereafter close after a suitable interval determined by the time delay mechanism shown in Figure 8 and hereinabove described.

It is to be noted that a relatively light spring 68 is secured to the reset lever 65 and to a pin 69 carried by the lever 51. The spring 68 is relatively light as compared to the spring 58 and serves merely to hold the lever 62, see Figures 4 and 12, in its uppermost position until the lever 62 has been rocked downwardly when the circuit breaker is locked out.

It is to be noted that the lever 62 does not move downwardly for each operation of the circuit breaker but only moves downwardly when i the look-out mechanism functions or when the lever 62 is manually pulled downwardly for manual operation of the circuit breaker.

It is to be noted that in the resetting operation, the lineman or operator is never subjected to any violent shock even though a fault may still persist when the circuit breaker is being reset. If the fault still persists while the circuit breaker is being reset, the circuit breaker will instantly move to full open position but nevertheless the lever 34, see Figure 1, will move upwardly away from the projection 59 of the lever 55 and consequently no blow will be imparted to the operator. The only force opposing the resetting is the spring 58 and the force due to the opening stroke of th circuit breaker is not imparted to the resetting lever 62.

It will be noted that the circuit breaker always has a quick opening stroke no matter whether it is released manually, thermally, or by electrical overload. It also has a quick closing stroke after a certain interval provided by the time delay mechanism as the final closing stroke'of the circuit breaker is unimpeded.

It will be noted that the lower portion of the circuit breaker as shown in Figure 1 is enclosed by the cylindrical casing 3 I. The upper and lower ends of this'.casing are closed except for the passageway leading into the cylinder 46 and the opening 30 through the bottom, which is normally closed by the downwardly seating valve 30'.

By having the lower portion of the circuit breaker encased in the casing 3|, it will be seen that when the circuit breaker opens under a violent overload, a considerable amount of gas is generated within the casing 31 and the plunger 41 is moved upwardly its full extent, thus tripping the trip lever 5i and causing the circuit breaker to be locked in'open position so that a succeeding violent action of the circuit breaker will not be permitted. This is, of course, an abnormal condition but nevertheless the circuit breaker will take care of itself under this abnormal condition.

This invention is designed to take care of still another abnormal condition where an overload occurs of too small a value to cause complete operation of the circuit breaker at one stroke, but nevertheless might cause partial opening followed by quick reclosing of the circuit breaker without having the circuit breaker execute a complete opening stroke. It is obvious that the repeated breaking will result in the generation of gas and the gas so generated will force oil into the cylinder 46, thereby driving the tripping plunger 41 upwardly and thus tripping the lockout mechanism.

Circuit breakers and fuses are frequently used in the same distribution system. It has not heretoiore been possible to properly coordinate the circuit breakers and the fuses. This invention provides a coordinator cooperating with the circuit breaker so as to properly coordinate the circuit breaker with fuses used in the same distribution system. The means for coordinating the circuit breaker with the fuses will now be described.

A bridging circuit having an impedance means such as a choke or resistor is arranged to bridge or parallel the actuating or magnet coil 14 under predetermined conditions. Referring to the diagrammatic view shown in Figure 3, it will be seen that the bridging circuit chosen for illustration comprises a resistor 10 and an auxiliary switch having stationary contacts II and a movable contact 12. This bridging circuit is connected in parallel with the actuating coil or magnet coil M. The construction is so arranged, as will appear hereinafter, that the bridging circuit is normally open as shown in Figure 3 but is closed upon the first operation of the circuit breaker, for example, on the first opening stroke of the circuit breaker. Thereafter the bridging circuit is maintained closed by delayed action mechanism and when the circuit breaker again closes, a larger current will have to pass through the circuit breaker before the circuit breaker will again open as part of the current is by-passed around the coil I4. The period of delay of the delayed action mechanism for opening the auxiliary switch is greater than the period of delay before the circuit breaker closes.

It is also within the province of this invention to provide a normally closed bridging circuit as shown in Figure 15 which is opened on the first operation of the circuit breaker so that after the first operation the circuit breaker will respond to smaller currents than required for the first operation. To accomplish this the movable contact I2, corresponding to the movable contact 12 of the first form of the invention, normally connects the stationary contacts H thus placing the impedance means 10 in parallel with the actuating or magnet coil H. This bridging circuit is opened on the first operation of the circuit breaker. The remaining portion of the mechanism is the same as previously described.

Consider the condition when a fault exists in a branch line protected by a fuse at a point beyond the circuit breaker. The circuit breaker will immediately respond to the overload current and will open the circuit usually prior to the time that the fuse will blow. However, before the circuit breaker can again operate, a larger current will have to pass through the circuit breaker and if the fault still persists, the fuse on the branch line will blow before the circuit breaker opens the second time and thus will disconnect the branch line from the main line and allow the main line to remain supplied with energy. On the other hand, if the fault has cleared, the circuit breaker will not execute the second operation and after a predetermined interval of time, the delayed action mechanism will open the auxiliary switch and the circuit breaker will be again set for its initial smaller current value.

The circuit breaker is therefore coordinated with the fuses so that it will protect the line against overload and yet if there is a persistent fault located on one branch line only, will allow this branch line to clear itself through the medi-' um of its individual fuse without paralyzing the entire network beyond the circuit breaker. The coordinator in no way interferes with the safety features furnished by the circuit breaker for if there is a persistent fault not cleared by any of the fuses, the circuit breaker will execute its required number of operations and will lock itself out and thus open the entire system beyond the circuit breaker.

" The mechanism for accomplishing the above enumerated functions will now be described in detail. It will beseen upon reference to Figures 1, 4, 13 and 14, that a pair of insulating plates 13 are rigidly bolted together and are rigidly supported by means of a bracket 14, see Figure 4, from the upper plate 6|. Between these plates a series of levers are mounted. A main actuating lever 15 formed of insulating material is pivotally mounted on the pin 16 and is urged in a clockwise direction by means of the spring 11. It is prevented from executing this movement, however, when the circuit breaker is closed as the insulating links 36 are provided with a projecting pin 18 which engages the upper face of the lever 15 and holds the-lever in the position shown in Figure 13. However, when the circuit breaker opens under overload, the parts will assume the position shown in Figure 14 and the spring 11 will cause the lever 15 to move in a clockwise direction to the position shown in Figure 14. The right-hand end of the lever 15 as viewed in Figures 13 and 14 is provided with a roller 19 which travels upon the upper face of an insulating lever 80 pivoted upon the pivot pin 8|. The lever 80 is spring urged in a counterclockwise direction by means of the spring 82. The spring 82 extends between the lever 89 and a lever 83 composed of a slides within the cylinder 93 and is connected pair of levers pivotally mounted adjacent their links 85 and 86 connected by means of the elongated pin 81. The pin 81 projects at opposite ends through apertures 88 formed in the side walls 13 and thus, together with the openings 88, constitutes stop means for limiting the upward and downward motion of the central portion of the toggle link mechanism. When the lever 80 is depressed to the position shown in Figure 14, it will force the pin 81, and consequently the toggle link mechanism 85, 86, downwardly slightly past dead center and the toggle link mechanism will thus be locked in this position against the collapsing action of the spring 82. The extended toggle link mechanism will rock the lever 83 to the right as viewed in Figure 14 and will cause the movable contact 12 of the auxiliary switch to connect the stationary contacts 11 and thus close the bridging circuit through the resistor 10.

The movable contact 12 is yieldingly urged outwardly by means of the leaf spring 89 and is carried by a pin 90 extending through a cylindrical member 9| carried between the two arms of the lever 83. Preferably guiding fingers 92 are provided at opposite ends of the movable contact 12 and these guiding fingers are positioned between the members forming the lever 83.

The coordinator includes delayed action mechwith the free end of the lever 89 by means of the connecting rod I00.

It is thus clear that when the lever 8!) is depressed, the piston 99 is driven downwardly. There is no retardation to this motion as the oil displaced upon downward motion of the piston 99 moves the valve 95 downwardly and allows the oil to escape through the openings 94. However, the piston is permitted to rise only slowly as the valve again closes the openings 94 and the oil now has to pass between the side walls of the piston 99 and the valve 95 and the inner wall of the cylinder 93. Obviously other leak means could be provided if desired.

When the circuit breaker again closes, the lever 15 is rocked to the position shown in Figure 13. However, the lever cannot immediately rise but can only travel upwardly very slowly due to the delayed action hereinabove described. As it travels upwardly after a suitable interval of time, a finger 89' integral with the lever 80 and underhanging the pin 81 will finally initiate the collapse of the toggle link mechanism 85, 86 by moving the pin 81 past dead center. The spring 82 will complete the collapsing of the toggle link mechanism and thus the auxiliary switch 12 will be opened with a quick opening motion. The auxiliary switch 12 also has a quick closing stroke due to the action of the spring 11 as there is no retardation to this motion.- If desired, the pair of links 86 of the toggle link mechanism on opposite sides of the lever 80 may be connected by an integral portion 86'.

It will be seen that this invention provides a circuit breaker having a coordinator which makes the circuit breaker suitable for use in distribution systems where many branch lines and fuses are employed.

Although this invention has been described in considerable detail, it is to be understood that such description is intended as illustrative rather than limiting, as the invention may be variously embodied and is to be interpreted as claimed.

We claim:

1. In a repeating circuit breaker, main switch means biased towards closed position, magnetic means including a coil and an armature for opening said main switch means when the current controlled by said circuit breaker exceeds a predetermined value, time delay means operatively associated with said main switch means for delaying the closing of said main switch means after opening of said circuit breaker, a bridging circuit arranged in parallel to said coil and including normally closed auxiliary switch means operated from said magnetic means and arranged to be automatically opened to alter the effect of said coil on said armature after an initial operation of said circuit breaker, and means independent of the current controlled by said circuit breaker and including time delay means set in operation by said armature and effective after operation of said circuit breaker and arranged 11 to control the action of said auxiliary switch means.

2. In a repeating circuit breaker, switch means biased towards closed position, overload means including a coil and an armature for opening the switch means when the current controlled by said circuit breaker exceeds a predetermined value, time delay means operatively associated with said switch means for delaying the closing of said switch means after opening of said circuit breaker, an impedance, auxiliary switch means operated from said armature and arranged to connect and disconnect said impedance in parallel with said coil to alter the action of said overload means to cause said overload means to open said switch means at a different value of current controlled by said circuit breaker after an initial operation of said circuit breaker, and means independent of the current controlled by said circuit breaker and including time delay means effective after closing of said circuit breaker and arranged to operate said auxiliary switch means for restoring said overload means to its initial condition.

3. In a repeating circuit breaker, switch means biased towards closed position, condition responsive means including a magnet coil and an armature for opening said switch means when the current through said coil exceeds a predetermined value, time delay means operatively associated with said switch means for delaying the closing of said switch means, a bridging resistor, auxiliary switch means actuated from said armature for automatically connecting said resistor in parallel with said coil after an initial opening of said switch means, automatic restoring means for opening said auxiliary switch means, and time delay means efiective after closing of said switch means for delaying the action of said restoring means.

4. A repeating circuit breaker comprising a main switch, a magnet coil and an armature for opening said'main switch when the current through said coil exceeds a predetermined value, a bridging circuit in parallel with said coil and including a resistor and an auxiliary switch, means controlled from said armature for closing said auxiliary switch on main switch opening motion of said armature, delayed action means operatively associated with said main switch for closing said main switch, and delayed action means for opening said auxiliary switch, said last mentioned delayed action means having a longer 12 delay period than said first mentioned delayed action means.

5. In a repeating circuit breaker, switch means, condition responsive means including a magnet coil and an armature for opening said switch means when the current through said coil exceeds a predetermined value, means for automatically closing said switch means, a bridging circuit including impedance means, normally ineffective spring means for connecting said bridging circuit in parallel with said coil, means operated directly by said circuit breaker for normally maintaining said spring means in an neiiective condition when said circuit breaker is closed, and means controlled by said circuit breaker for rendering said spring means efiective after an initial operation of said circuit breaker.

6. In a repeating circuit breaker, switch means, condition responsive means including a magnet coil and an armature for opening said switch means when the current through said coil exceeds a predetermined value, means for automatically closing, said switch means, a bridging circuit including impedance means normally connected in parallel with said coil, and means controlled from said switch means 'for opening said bridging circuit after an initial operation of said circuit breaker.

'7. In a repeating circuit breaker, switch means, condition responsive means including a magnet coil and an armature for opening said switch means when the current through said coil exceeds a predetermined value, means for automatically closing said switch means, a bridging circuit including impedance means normally connected in parallel with said coil, normally ineffective spring means for opening said bridging circuit, and means operated from said switch means for rendering said spring means effective after an initial operation of said circuit breaker.

WILLIAM D. KYLE, Ja. CARL SCHINDLER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,648,508 Schweitzer Nov. 8, 1927 1,705,676 Parsons Mar. 19, 1929 2,312,174 Kaufmann Feb. 23, 1943

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