US2727958A - Circuit interrupters - Google Patents

Description

Dec. 20, 1955 L. v. CHABALA 2,727,953

CIRCUIT INTERRUPTERS Filed Feb. 26, 1955 2 Sheets-Sheet l Fig.l.

WITNESSES: INVENTOR Z4 77% Leonard V.Chobolo. U BY -:r-.

Dec. 20, 1955 v, CHABALA 2,727,958

CIRCUIT INTERRUPTERS Filed Feb. 26, 1955 2 Sheets-Sheet 2 Fig. 2.

WITNESSES: INVENTOR 4 71/;/

Leonard V.Chobolo. 20m q 4 6 ATTORN United States Patent Ofiice CIRCUIT INTERRUPTERS Leonard V. Chabala, Pittsburgh, Pa., assignor to Westinghouse Electric Corporation, East Pittsburgh, P2,, a corporation of Pennsylvania Application February 26, 1953, Serial No. 338,977

16 Claims. (Cl. 20089) My invention relates generally to circuit interrupters and it has reference in particular to automatic reclosing circuit breakers.

Generally stated, it is an object of my invention to provide for facilitating inspection of a reclosing circuit breaker after a predetermined number of operations.

More specifically, it is an object of my invention to provide for effecting lockout of a reclosing circuit breaker after a predetermined total number of operations of all kinds, as well as upon a lesser number of closely consecutive operations.

Another object of my invention is to provide for counting the operations of a reclosing circuit breaker and preventing reset of the operation counter thereof after a relatively large number of operations, so as to insure a lookout operation regardless of whether such operations are closely consecutive or not.

Yet another object of my invention is to provide for braking the counter of a reclosing circuit breaker to prevent reset, after a predetermined total number of operations are attained, by means of a brake which requires removal of the tank before it can be released, thereby making the circuit breaker accessible for inspection.

A further object of my invention is to provide for increasing the reset time of a counter in a reclosing circuit breaker so as to delay operation of the breaker on relatively widely spaced operations after a relatively large number of total operations.

It is also another object of my invention to provide in an automatic reclosing circuit breaker for changing the reset time of an operation counter after a predetermined number of operations of the circuit breaker.

Other objects will in part be obvious, and will in part be explained hereinafter.

In practicing my invention, in accordance with one of its embodiments, a counting device which is actuated upon operation of a reclosing circuit breaker and is normally disposed to reset slowly between such operations so as to count only closely successive operations for effecting lockout of the circuit breaker after a predetermined number of such operations, is provided with a brake which is rendered effective only after a relatively large number of operations to prevent reset of the counter. Consecutive operations of the breaker after the brake is set progressively advance the counting device which, because it is prevented from resetting, soon locks the circuit breaker in the open position. The brake is located within the breaker tank so that the tank must be dropped to release it. This insures making the contacts and arc-extinguishing oil available for inspection to determine the operating condition of the breaker.

For a more complete understanding of the nature and scope of my invention, reference may be made to the following detailed description which may be read in connection with the accompanying drawings, in which:

Figure 1 is a substantially central vertical section broken out in part, of a circuit breaker constructed in accordance with the teachings of this invention;

2,727,958 Patented Dec. 20, 1955 Fig. 2 is an enlarged partly sectioned plan view of a portion of the circuit breaker showing details of the operation counter and totalizer; and

Fig. 3 is an enlarged partial elevational view of the operation counter and totalizer of the circuit breaker shown in Fig. 1.

The circuit breaker shown in Fig. 1 of the drawing is substantially identical with that disclosed and described in detail in the Patent No. 2,622,167 of H. L. Rawlins et al., filed December 31, 1946, issued December 16, 1952, entitled Circuit Interrupters, and assigned to the same assignee of this invention, except that the dashpot arrangement is changed to that of copending application Serial No. 7l9,524 (W. E. Case 24,719) of James M. Wallace et al., filed on December 31, 1946, entitled Circuit Interrupters, and also assigned to the same assignee of this invention. It is illustrated as being mounted in a metal tank 2 having a closed bottom wall and an open top. Preferably, the tank is adapted to be lined at least over the bottom Wall and up to a point adjacent the open top of the container with a liner 3 of insulating material, such as fiber or the like, and is filled up to the level L with a liquid, preferably a liquid having arc-extinguishing ability, such as oil. The upper end of tank 2 is provided with an outwardly extending flange 4 on which the flange 8 of a cover casting 6 is adapted to be seated, preferably with a gasket 10 interposed therebetween. The flange 8 of cover casting 6 may be provided with an integral lip 12 and the cover may be secured to the tank in any desired manner, such, for example, as by bolts (not shown) secured to suitably formed brackets on the tank.

The breaker contacts and certain of the contact actuating mechanism are adapted to be supported in tank 2 from cover casting 6 by means of a number of integral supporting lugs 16 (only one of which is shown), depending from the top Wall of the cover casting and adapted to engage insulating spacer rods 18 having threaded studs (not shown) engaging threaded openings in rods 18 and lugs 16 and lugs on a supporting casting 20. A supporting plate 22 may be supported in a similar manner from casting 20 so that a solenoid coil 24 may be mounted between casting 20 and supporting plate 22 with the central opening in the coil aligned with openings provided in casting 20 and plate 22.

Spaced stationary contacts 26 of the breaker are each supported from plate 22 by a support tube 28 of insulating material, such as fiber, with the stationary contacts being mounted on tube 28 by means of screws 30 and with the upper end of the tube 28 having brackets 32 by means of which the support tube is secured to supporting plate 22.

Stationary contacts 26 are adapted to be closed by engagement therewith of a bridging contact 36 having contact tips 38 at opposite ends thereof for engagement with the stationary contacts, respectively. Bridging contact 36 is supported substantially centrally thereof on a slidable contact actuating rod 44 by pivot pin 40 for limited pivotal movement about a transverse axis, with contact actuating rod 44, being mounted for longitudinal sliding movement through coil 24 and the aligned openings in plate 22 and casting 20. It will be observed that bridging contact 36 is free to adjust itself to the stationary contacts by restricted pivotal movement about its pivot mounting 40. Contact rod 44 should be of insulating material, such as fiber or a molded insulating material.

The upper end of contact actuating rod 44 has a pair of connecting links 46 pivoted at each side thereof and pivoted thereon as by a pivot pin 48 with the upper ends of these connecting links mounted on a common pivot pin 50 for a pair of toggle levers 52 and 54. Toggle levers 52 and 54 are both formed of sheet material with Q lever 54 being bent to substantially channel form with an outwardly extending flange 56 at each side adapted to be received at the free ends thereof in recesses 58 provided in the spaced downwardly depending fingers of an angled supporting bracket 60 which, in turn, is secured as by a screw 64 to :1 lug 62 integral with he cover casting. Preferably the base of the channel part of toggle 54 is extended at 66 through the space between the supporting fingers of bracket 60, and at the other end of lever 54 the sides of the channel formation: thereof are extended to be mounted on the pivot pin 54). A coil tension spring 68 has one edge hooked into an opening provided in toggle lever 52 and has the opposite end thereof hooked over an integral spring support on the the breaker, toggle lever 54 will pivot about recesses 58 and the line of action of toggle spring 68 will thus be caused to approach that pivot point, so that in response to a very small contact separation the line of action of toggle spring 68 will pass through pivot recesses 58, which is the on-center position of the resilient toggle arrangement comprising toggle levers 52 and 54 and toggle spring 68. As a practical matter the opening movement of the contacts necessary to move toggle levers 52 and 54 to the on-center position mentioned above may be made very small, in one operating device, being on the order of one-quarter of an inch.

When toggle levers 52 and 54 reach their on-center position referred to above, further relative movement of the two toggle levers in the same direction is prevented because the upper edge of toggle lever 52 engages the base of the central channel formation of toggle lever 54. Moreover, since the point at which toggle spring 68 is hooked into the opening of lever 52 then substantially coincides with recesses 58 in which toggle lever 54 pivots during contact opening movement, it will be apparent that the remaining major part of contact opening movement will occur substantially uninfluenced by toggle spring 68. Substantially the reverse of the above operation occurs when contact operating rod 44 moves downwardly to close the circuit from the full open contact position, because during the first and major part of contact closing movement, levers 52 and 54 will be in engagement so that such movement will'be uninfluenced by toggle spring 68. However, as soon as pivot 50 passes below a line drawn from the remote end of toggle spring 68 through pivot recesses 58 for link 54, toggle spring 68 will then be effective to move the toggle levers to the full line position shown in Fig. l, and the force exerted by toggle spring 68 then tending to close the contacts will continue to increase as toggle levers 52 and 54 move further away from their on-cerrter positions. While it is preferred that when toggle levers 52 and 54 are in engagement, these levers be engaged as closely as possible to their on-center position so that toggle spring 68 is ineffective to bias the contacts in either direction, rather than risking that engagement occur at a position slightly overcenter from that shown in Fig. 2, it may be desirable to make the engagement occur just prior to attainment by levers 52 and 54 of their on-center position. When this is done, toggle spring 68 will exert some slight bias tending to close the contacts and this may be desirable in some cases. It Will be noted that toggle lever 52 is provided with an intergral hook 73 for limiting separation of this lever from toggle lever 54.

Solenoid coil 24, previously mentioned, is adapted to be energized under certain conditions for automatically opening the circuit breaker contacts. The central opening through coil 24 preferably is provided with a cylindrical sleeve 74 in which a solenoid core 76 is adapted to be slidably mounted in a piston-like manner. The sleeve 74 communicates with an annular passage 78 in the casting which connects with a passage 80 therein having a threaded end opening 81 for receiving a plug (not shown), if all time delay operation is desired.

A contact actuating sleeve 82 is telescoped over contact operating rod 44, and its lower end is received in the core 76 and preferably threadably mounted therein. A coil compression spring 83 is provided within actuating sleeve 82 on contact operating rod 44 and is adapted to react between a shoulder in the core and a pin 84 extending transversely through the actuating rod 4-4. A bushing 85 surrounds the sleeve 82 and is provided with a flange 86.

The circuit through the circuit breaker thus far de scribed may now be traced from the point where it enters tank 2 through one of a pair of terminal bushings 90 (only one being shown) with each bushing secured to cover casting 6 as by bolts 94 and each being provided with a conductor element which extends through the bushing and emerges from a reduced extension 96 of the bushing v seated in an opening provided in the top wall of cover casting 6, and proceeds by conductor 98 directly to one fixed Contact 26 of the breaker. When the contacts are in engagement, the circuit then proceeds through bridging contact 36 to the other fixed contact 26, and then by way of a conductor 1% to one terminal of solenoid coil 24. The other terminal of coil 24 is adapted to be connected by a conductor 102 to the conducting means in the other terminal bushing 90. It will be apparent that the solenoid 24 in this embodiment of the invention is connected in series in the circuit through the circuit breaker so as to be energized at all times when the circuit breaker is closed an amount depending upon the value of the current flowing in the circuit.

For any given rating of circuit breaker, solenoid coil 24 is designed to become sufiiciently energized when the load current in the circuit exceeds its rating as to attract core 76 and move it upwardly within sleeve 74. Core 76 will move upwardly relatively rapidly if the passage is open and slowly if it is closed, since it is necessary to displace the liquid in sleeve 74 above the core, either through the opening 81 or through relatively small clearances between the core and sleeve 74. Accordingly, if the opening 61 is open as shown, opening movement of the core will not be slowed up by the aforesaid dashpot action, and opening movements thereof may be relatively rapid. When core 76 commences its upward travel, the bridging contact 36, being held engaged by toggle spring 68 does not move, so that spring 83 is compressed until it is substantially solid, at which point the upper end of bushing strikes a collar 87 secured to rod 44. Thereupon actuating rod 44 moves upwardly, and the force exerted by toggle spring 68 begins to decrease and in a very short distance has substantially no value at all, so that the remaining major part of the circuit opening movement of bridging contact 36 occurs extremely rapidly due to the expansion of spring 83.

When the circuit breaker contacts have attained their full open circuit position, the parts associated therewith are biased to return by gravity, and as previously pointed out, they may also be biased by toggle spring 68 if it is desired to stop relative movement of the toggle levers 52 and 54 just short or attaining their on-center position during opening of the contacts. In either case, the closing bias is relatively light and will not be appreciably 0pposed by the dashpot action of core 76 if the passage 80 is open. Accordingly, the return movement will be substantially under the influenceof gravity until the pivot point 50- moves below a line extending throughpivot recesses 58 and the fixed end of spring 68, whereupon bridging contact will be rapidly moved to etfect a snap action closing of the breaker contacts by toggle spring 68.

In order to limit the number of operations of the circuit breaker in close succession upon the occurrence of a continuing overload on the circuit and to provide for manual operation, means are provided for holding the breaker contacts open in response to the occurrence of a predetermined number of closely succeeding circuit-interrupting operations, and which can also be manually actuated. This means comprises a toggle lever 104 pivoted at one end as at 106 on a U-shaped spring lever 108 which, in turn, is pivotally supported as at 110 between the legs of a U-shaped supporting bracket 111 secured to cover casting 6. The other end of toggle lever 104 is pivoted as by a pivot pin 112 to the adjacent end of a second toggle lever 114 and this, in turn, is mounted on a pivot pin 116 intermediate its ends with the pin 116 being mounted in a bracket 118 secured to the adjacent wall of cover casting 6. A slot 120 is provided through the cover casting 6 for receiving the other end of toggle lever 114 which acts as a manual operating handle at the exterior of the circuit breaker casing, being provided with an angled hook end 122. A coil compression spring 124 is mounted to react between the bight of the spring lever 108 and cover casting 6. Normally toggle levers 104 and 114 are held by spring 124 with pivot 112 below the center line connecting pins 106 and 116, with the outer end of lever 114 positioned in and beneath an integral hood 126 on cover casting 6 in engagement with an adjustable stop screw 128 mounted in the hood.

In the position of toggle levers 104 and 114 illustrated, they have no effect on operation of the circuit breaker, being normally inactive in this respect. However, lever 108 has a connecting pin 113 extending beneath toggle levers 52 and 54. Accordingly, if it is desired to manually open the circuit breaker contacts, a hook stick or similar operating member may be engaged with the upper side of angle hook 122 of toggle lever 114 and pulled downwardly to rotate the toggle lever in a counterclockwise direction about its supporting pivot 116 to move toggle levers 104 and 114 overcenter in an upward direction, and in doing this, pin 113 engages toggle levers 52 and 54 and moves them upwardly in a counter clockwise direction, thus carrying contact actuating rod 44 upwardly to separate bridging contacts 36 from stationary contacts 26. The contacts will be held open by spring 124 which maintains toggle levers 104 and 114 in their upper overcenter position. In thus manually opening the circuit, after toggle spring 68 is moved to its on-center position, it will be observed that the spring 124 is only required to maintain the contacts of the breaker open against the relatively light closing bias due to gravity, and such light bias as may be due to toggle spring 68, in the event that toggle levers 52 and 54 .are stopped just prior to reaching their on-center position, with the breaker contacts maintained at their open circuit position following the manual circuit opening operations described above. It will be apparent that the outer end of toggle lever 114 projects below hood 126 of cover casting 6 so as to provide a readily visible indication that the breaker contacts are maintained at open circuit position. It will further be apparent that the breaker contacts may then be closed only by manual operation of toggle lever 114 in the opposite direction, that is, by exerting an upward force on the outer end of the toggle lever by engagement of a hook stick or the like with the underside of hook 122 to rotate lever 114 in a clockwise direction to move it and toggle lever 104 back overcenter to the full line position illustrated in the drawing. This manual operation of toggle lever 114 does not directly close the breaker contacts, but merely permits closure of the contacts in the manner previously described, that is, initial closing movement of the contacts being due to the bias of gravity and possibly some slight bias to the toggle spring 68, until bridging contact 36 is closely adjacent the stationary contacts 26, when toggle spring 68 is moved below its on-center position and suddenly becomes effective to finally move the contact into engagement rapidly. lt will be observed that on manual opening of the circuit the full force of spring 124 becomes effective to open the contacts as soon as levers 104 and 114 move overcenter, and actual opening of the contacts by spring 124 is independent of the operating hook stick. Similarly, in manually resetting toggle levers 104 and 114, there is no possibility that withdrawal of the hook stick after resetting can disturb the position of toggle levers, because in resetting, the hook stick engages only the lower edge surface of hook 122.

An integrating mechanism for automatically moving toggle levers 104 and 114 upwardly overcenter and thus preventing reclosure of the circuit breaker in response to a predetermined number of closely successive circuit-interrupting operations is provided, comprising a cylindrical tube 130 clamped or otherwise secured in a lateral extension of casting 20 at the top of solenoid coil 24, and this tube has a plug 132 threaded into the lower end thereof, with the plug having a small central opening controlled by a ball check valve 134 which permits flow of fluid into the lower end of tube 130 but prevents outflow. An integrating piston 136 is mounted in the tube 130 and normally rests on the upper end of plug 132, being provided with a reduced extension 138 at the upper end thereof having a plurality of spaced circular flanges 140 forming rack teeth thereon, and having an elongated extension 142 of insulating material on the extreme outer end thereof which is positioned below an extension 143 of the toggle lever 104.

A pawl lever 144 is pivotally mounted at one end as at 146 with this end of pawl lever 144 being split with the legs thereof located on each side of tube 130 and with pivot 146 supported on spaced supporting flanges integral with casting 20. Pawl lever 144 has a connecting web intermediate its ends and at the outer end thereof the sides of the lever are extended outwardly and laterally as at 148 to normally be in engagement with flange 86 adjacent the upper end of actuating tube 82. Pawl lever 144 is normally biased into engagement with flange 86 by a coil tension spring 152 hooked over the remote edge of the web of the pawl lever at one end and anchored to an ear integral with casting 20 at its other end. Pawl lever 144 is provided with a pawl member 154 pivoted thereon as at 156 and biased by a spring 158 in a counterclockwise direction to a position wherein a portion of pawl member 154 engages the connecting web of pawl lever 144.

The tube 130 intersects the passage 80 of the dashpot, and the piston 136 acts as a valve to control venting thereof. With the piston as shown, the dashpot vents freely and operation of the breaker is rapid. When the piston 136 is moved upwardly by the pawl 154 it first partially, and then completely blocks the passage 80, so as to delay operation of the armature 76 at first slightly and then with an inverse time current characteristic.

When the circuit breaker operates to open the circuit, flange 86 will be carried upwardly with actuating sleeve 82 and thus carry the free end of pawl lever 144 upwardly with it to move pawl member 154 into engagement with one of the upper flanges 140 on integrating piston 136, to thus carry the piston upwardly a predetermined distance. When the breaker recloses following such a first circuit-interrupting operation. integrating piston 136 is left at the position to which it was advanced since pawl member 154 is free to disengage circular flanges 140, and if the breaker remains closed, integrating piston 136 will slowly reset to the position shown in Fig. 1, due to leakage of liquid in the cylinder 130 below the piston 136, through the relatively small clearance between the cylinder and the piston. However, if the breaker immediately reopens after a first opening and rcclosing operation, pawl member 154 this time will engage the next lower circular flange 140' of the integrating piston and raise the piston 21 further amount. Subsequent reclosing will result then in leaving the piston 136 at this further advanced position, from which it will eventually reset if the breaker remains closed. However, in the event of a continuing overload, the breaker will again open and reclose, and evenutally the pawl member 154 will advance integrating piston 136 an amount sufficient to cause the upper extension 142 thereof to engage the extension 143 of toggle lever 104 and move lever upwardly oyercenter so that the toggle spring 124 will maintain the contacts separated in themanner previously described.

It is thus apparent that toggle levers 104 and 114 will be automatically moved upwardly overcenter to maintain the circuit breaker contacts separated only in response to a predetermined number of closely successive circuit opening and closing operations, usually four such operations. However, in the event a lesser number of closely successive opening and closing operations occurs, the integrating mechanism will reset, and the breaker contacts will be automatically held open only when the aforesaid predetermined number of opening and closing operations occurs in close succession. Obviously, after the breaker contacts have been automatically actuated to a position where they are held open by toggle spring 124, they can be reclosed only by manual operation of the toggle lever 114 in the manner previously described.

In accordance with the teachings of my invention, a novel means is provided-for insuring servicing of the circuit breaker hereinbefore described, after a predetermined maximum number of operations, regardless of Whether they be closely successive or Widely spaced, since the operating condition of the contacts and the condition of the insulating oil is largely dependent upon the total number of circuit-interrupting operations which has taken place. For this purpose, the circuit breaker has been provided with totalizing means designated by the nu meral 170, and shown somewhat generally in Fig. l and in detail in Figs. 2 and 3. Referring particularly to Figs. 2 and 3 of the drawings, it will be seen that the integrating piston 136 of the counter may be provided with brake means, such as the split clamp device 172, which may comprise a portion at the upper end of the tube 130, split so as to effect a clamping relation with the upper end or flanges 14b of the extension of the piston 136. The clamp 172 may be normally disposed so that the upper extension 142 and flanges 140 of the piston 136 slide relatively freely therethrough. means comprising a threaded shaft 173 may be provided which extends freely through a lug 1'71 and is threaded into a lug 174 of clamp 172. An enlarged portion 168 of shaft 173 provides a shoulder for engaging lug 171 for effecting clamping engagement of the clamp 172 with the flanges 14b of the counting piston 136. Operation of the threaded shaft 173 may be effected by means of a ratchet or gear wheel 175 mounted on the shaft 173, being" secured to the enlarged portion 168, and actuated by means of a spring pawl 176 mounted on a lever 178 which is pivotally mounted on the enlarged portion 168 of the shaft 173 by means of a screw 169 and washer 182 for movement relative thereto. Means such as a plug 177 of fibre rod, plastic or the like inserted in a bore 179 in lug 174 engages shaft 173 to prevent overtravel or reverse rotation of shaft 173 by pawl 176. Operation of the lever 178 may be effected by operatively connecting the lever 17% to the operating lever 144 of the counter, as by a link 180 pivotally connected to the outer end of lever 178 by a pivot 181 and by the pivot 156 of pawl 154 to lever 144.

Each time the breaker operates, lever 14 is actuated in a counterclockwise direction by flange 86 as core 76 moves upwardly to separate contacts 38 and 26. The pawl lever 178 is likewise moved counterclockwise by link Operating i o the circuit breaker by but 180 and pawl 176 actuatesratchet wheel 175 in a direc tion to tighten threaded shaft 173 for effecting operation of clamp 172. As the breaker recloses, pawl 176 moves clockwise, leaving wheel 175 in its advanced position. The pawl 176 and the threaded shaft 173 may be suitably arranged so-that it requires, for example, about one hundred operations of the lever 144 to secure the necessary advancement ofthe threaded shaft 173 to effect clamping of the clamp 172 with the extension of the counting piston 136. Since lever 178 is mounted on the end of shaft 173 it moves laterally therewith, thus maintaining pawl 176 in operating relation with wheel 175. When a clamping relation is attained, reset time of the counting piston 136 will be changed, being sufficiently retarded or even prevented by reason of the braking action of the clamp 172 therewith. Under these conditions, successive operations of the circuit breaker, whether closely successive or widely spaced, will each still result in progressive advancement of the counting piston 136, so that the extension 142 thereof will in three or at the most four additional operations of the circuit breaker engage the depending extension 143 of lever 104 to effect operation of the lockout means to lock the contacts of the breaker in the open position. In addition to delaying or preventing reset of the counter, the operating time of the breaker is increased because of the valve action of piston 136, just prior to lockout, even for widely spaced apart operations. This alfords added protection for the breaker under conditions when unnecessary openings may cause damage because of the contaminated condition of the oil.

Since reset of the brake 172 cannot be effected without lowering the tank 2 from the cover casting 6, it will thus be seen that this will afford an ideal opportunity to service inspecting the contacts and examining the condition of the insulating oil. While the number or operations of a circuit breaker of the automatic reclosin'g type between service inspections may vary, it is believed that inspection of the contacts and oil is best eflected at approximately every hundred operations of the breaker. This will afford suflicient opportunity to ascertain the operating condition thereof.

From the above description and the accompanying drawings, it will be apparent that l have provided in a simple and effective manner for insuring periodic inspection and maintenance of the contacts and insulating oil of an automatic reclosing circuit breaker. Since such circuit breakers are generally located at more or less remote locations, they may be overlooked with regard to inspection and maintenance. it will be realized that the use of a totalizing device, as disclosed in my invention, maybe highly advantageous, particularly in the more or less remote locations. The features of my invention may be readily embodied in existing circuit breakers with a minimum of modification, and the device that I have disclosed for performing this totalizing function is both simple and inexpensive to manufacture and is reliable and effective in operation.

Since certain changes may be made in the abovedescribed construction and different embodiments of the invention may be made without departing from the spirit and scope thereof, it is intended that all the matter contained in the above description and shown in the accompanying drawings shall be considered as illustrative and not in a limiting sense.

I claim as my invention:

1. in a circuit interrupter, separable contacts, an opcrating mechanism for said contacts, electroresponsive means operable to actuate said mechanism to effect separation of said contacts, lockout means operable to actuate said mechanism to maintain said contacts separated, a counter having a member advanced by closely consecutive operations of the electroresponsive means to operate the lockout means in response to a predetermined number of closely consecutive operations of the electroresponsive means only, and totalizing means actuated by the electroresponsive means operable in response to a predetermined total number of operations of the electroresponsive means greater than the aforesaid predetermined number to effect operation of the lockout means.

2. In a circuit interrupter, separable contacts, operating means for said contacts, electroresponsive means operable in response to a predetermined value of current to actuate the operating means to effect separation of said contacts, lockout means operable to bias the operating means to maintain said contacts separated, a counter member normally advanced a predetermined amount by a predetermined number of closely consecutive operations of the electroresponsive means to effect operation of the lockout means, and totalizing means actuated by a predetermined total number of operations of the electroresponsive means to effect advance of the counter member to effect operation of the lockout means in response to operations including other than closely consecutive operations of the contact separating means.

3. A circuit interrupter comprising, separable contacts, an operating mechanism for said contacts, electroresponsive means operable to actuate said mechanism to separate said contacts, said contacts being biased to reclose following separation, lockout means operable to hold the mechanism in a position to maintain said contacts separated, a counter having a member advanced a predetermined amount by each operation of the electroresponsive means, said member being biased to reset slowly so as to be progressively advanced to effect operation of the lookout means in responsive to a plurality of closely consecutive operations of the electroresponsive means, and means including an additional non-resetting counting means actuated by the electroresponsive means to prevent reset of said member and effect operation of the lockout means at a predetermined total number of operations of the electroresponsive means greater than said plurality.

4. A circuit interrupter comprising, separable contacts having operating means biased to close them, electroresponsive means operable in response to a fault condition to actuate the operating means to effect separation of said contacts, a counter having a movable member advanced a predetermined amount by each operation of the electroresponsive means, said member being biased to reset slowly, lockout means actuated by said member operable to bias the operating means to maintain the contacts separated in response to a predetermined movement of said member, and means actuated by a predetermined number of operations of the electroresponsive means to prevent reset of said member.

5. A circuit interrupter comprising, separable contacts, operating means for said contacts, means biasing said operating means to close said contacts, electroresponsive means operable in response to a predetermined value of current through said contacts to actuate the operating means to effect separation of said contacts, lockout means operable to actuate the operating means to maintain said contacts separated, a counter having a movable member to actuate said lockout means, advancement means actuated by the electroresponsive means advancing the movable member in response to each movement of the electroresponsive means, said movable member being biased to slowly reset, so as to obtain progressive advancement thereof to effect actuation of the lockout means in response to a predetermined number of closely consecutive operations of the electroresponsive means, and additional counting means actuated by the advancement means operable in response to actuation of said advancement means a number of times greater than said predetermined number of times to further delay reset of said movable member.

6. A circuit interrupter comprising, separable contacts, operating means therefor, electroresponsive means operable in response to a predetermined value of current to effect operation of the operating means to effect separation of said contacts, said operating means being biased 10 to reclose said contacts following such separation, lockout means actuated by the electroresponsive means operable to bias the operating means to maintain said contacts separated, a counter having a movable member advanced a predetermined amount by each operation of the electroresponsive means, means including a check valve providing delayed reset of said member so as to provide for progressive advancement of said member to actuate the lockout means and effect operation of the lookout means in response to a predetermined number of closely successive operations of the electroresponsive means, and means actuated by the electroresponsive means on each and every operation of the electroresponsive means operable to prevent reset of said member, only after a total number of operations in excess of said predetermined number.

7. In a circuit interrupter, separable contacts, an operating mechanism therefor, electroresponsive means having a part movable in response to a predetermined current condition to actuate the operating mechanism to effect separation of said contacts, said mechanism being biased to reclose the contacts following a separation, a counter having a movable member and actuating means therefor actuated by said movable part, dashpot means including a check valve for delaying reset of said movable member so as to effect progressive advancement thereof in response to a plurality of closely successive operations of the electroresponsive means, lockout means actuated by the movable member in response to a predetermined advancement thereof to bias the mechanism to maintain said contacts separated, and normally ineffective reset preventing means actuated by the electroresponsive means operable in response to a predetermined total number of operations of the electroresponsive means greater than said plurality to prevent reset of the movable member between operations.

8. A circuit interrupter comprising, separable contacts having an operating mechanism biased to close them, electroresponsive means operable in response to a predetermined current condition to actuate said mechanism to effect separation of said contacts, lockout means operable to bias the mechanism to maintain said contacts separated, counting means advanced by a predetermined number of closely consecutive operations of the electroresponsive means to effect operation of the lockout means, and totalizing means actuated by the electroresponsive means operable in response to a predetermined total number of operations of said electroresponsive means in excess of said aforesaid predetermined number of closely consecutive ones to effect operation of the lockout means. i

9. In a circuit interrupter, separable contacts, an operating mechanism for said contacts electroresponsive means operable in response to a predetermined value of current to actuate said mechanism to effect separation of said contacts, said contacts being biased to re close following such separation, lockout means operable to bias the mechanism to maintain said contacts separated, a counter having a member normally advanced progressively only by a predetermined number of closely consecutive operations of the electroresponsive means to effect operation of the lockout means, and totalizing means actuated by the electroresponsive means operable in response to a total number of operations in excess of the predetermined number of closely consecutive ones to engage the counter member to effect progressive advancement of the counter member on consecutive operations of the electroresponsive means regardless of the time interval between them.

10. In a circuit interrupter, separable contacts, operating means therefor, electroresponsive means operable in response to a predetermined value of current to actuate the operating means and effect separation of said contacts, lockout means operable to bias the operating means to maintain said contacts separated, counting means actuated by the electroresponsive means normally operable to actuate and effect operation of the lookout means only in response to a predetermined number of closely consecutive operations of the electroresponsive means, and totalizing means actuated by the electroresponsive means operable to effect operation of the lockout means in response to a greater number of operations of the electroresponsive means including those too widely spaced apart to normally efiect operation of the counting means.

11. A circuit interrupter comprising, separable contacts, operating means therefor, electroresponsive means operable in response to a predetermined value of current to actuate the operating means to efiect separation of said contacts, said operating means being biased to reclose said contacts following such separation, lockout means operable to bias the operating means to maintain said contacts separated, countirw means including a normally self-resetting member normally progressively advanced by the electroresponsive means to operate the lockout means in response to closely consecutive operations of the electroresponsive means, and totalizing means actuated by the electroresponsive means operable after a predetermined number of operations of the electroresponsive means to prevent resetting and effect progressive advancement of the movable member even in response to widely spaced operations thereof.

12. In a circuit interrupter, separable contacts having operating means biased to close them, electroresponsive means operable in response to a predetermined value of current to actuate said operating means to efiect separation of said contacts, dashpot means delaying operation of said contacts, counting means having a member advanceable from a normal position to vary the delay of the dashpot means and having a delayed reset time, a lever operated by the electroresponsive means for actuating the movable member, lockout means actuated by the advanceable member upon predetermined advancement thereof, and means including a totalizer actuated by said lever for increasing the reset time of the advanceable member.

13. A circuit interrupter comprising, separable contacts, operating means for said contacts, electroresponsive means operable to effect operation of the operating means to efiect separation of said contacts, lockout means operable to bias the operating means to maintain said contacts separated, counting means having a member advanced by a predetermined number of closely consecutive operations of the electroresponsive means to effect operation of the lookout means, said member having a delayed reset time between movements, and totalizing means actuated by the electroresponsive means operable in response to a predetermined number of operations of the electroresponsive means to change the reset time of the counting means.

14. A circuit interrupter comprising, separable contacts having an operating mechanism biased to close them, electroresponsive means operable in response to a fault condition to actuate the operating mechanism to effect separation of said contacts, lockout means operable to actuate the mechanism to maintain said contacts separated, counting means having a movable member advanced by the electroresponsive means a predetermined amount from an initial position in response to each operation of the electroresponsive means, said member being slidably disposed in a cylinder having a check valve and being biased to return to said initial position so as to have a delayed reset time between advancements, and a totalizer actuated by the electroresponsive means operable in response to each operation of the electroresponsive means to progressively advance a member efiective to increase the reset time of the movable member after a predetermined number of operations of the electroresponsive means.

15. A circuit interrupter comprising, separable contacts having operating means biased to close them, electroresponsive means operable to actuate the operating means to effect separation of said contacts, lockout means operable to bias the operating means to maintain said contacts separated, a counter having a movable member, actuating means actuated by the electroresponsive means operable to effect advancement of said member in response to operation of the electroresponsive means, dashpot means delaying reset of said movable member, clamp means operable to engage the movable member to prevent reset of the movable member, and a screw member actuated by the actuating means to operate the clamps means.

16. A circuit interrupter comprising, separable contacts, operating means for said contacts electroresponsive means operable in response to a predetermined value of current to actuate said operating means to effect separation of said contacts, time delay means operable to delay movement of said electroresponsive means to effect separation of said contacts, counting means actuated by the electroresponsive means operable in response to closely consecutive operation of the electroresponsive means to vary the delay of the time delay means, and totalizing means actuated by the electroresponsive means operable to vary the delay of the time delay means in response to a predetermined total number of operations of the electroresponsive means including relatively widely spaced apart operations.

References Cited in the file of this patent UNITED STATES PATENTS 508,652 Thomson Nov. 14, 1893 2,069,082 Walle Jan. 26, 1937 2,601,188 Wallace June 17, 1952 2,622,167 Rawlins et al. Dec. 16, 1952

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