US2660635A - Air operated circuit breaker - Google Patents

Description

Nov. 24, 1953 Filed Dec. 8. 1948 J. D. woon 2,660,635

AIR OFERATED CIRCUIT BREAKER 5 Sheets-Sheet l INVENTOR.

Qae/J/z D. blood. B Y

ATTORNEYS.

Nov.- 24, 1953 J. D. woon 2,660,635

AIR OPERATED CIRCUIT BREAKER Filed DeC. 8, 1948 5 Sheets-Sheet 2 82 161 190 IIL/r 1 w1 F 19e R197 185 95 20o f g 185 3o 11 J 40 33 11 I L5 M q /j 2 A mvENToI.

m Qfl? @OMM Y @6M Nov. 24, 1953 J. D. wooD 2,660,635

AIR OPERATED CIRCUIT BREAKER Filed Dec. 8, 1948 5 Sheets-Sheet 5 4 1251. L 157 if 1g 3 141 215 191 176% Vw 15 216 V 175 6152155' 154 139 I 1'67 i 17a 18o 17e m 181 65 n 12a 129 *I 140 H 8 M195 184 l 173 f: F' 19 197 185 Oo 6 32 4o 55 "'11 5L J v INVENTOR. BY Qde/:a D. Jdozl ATTORNEYS.

Nov. 24, 1953 Filed Dec. 8, 1948 J. D. WOOD AIR OPERATED CIRCUIT BREAKER 5 Sheets-Sheet 4 INVENTOR.

By Qca effi h/foaf (9W YW dtml/myd Nov. 24,' 1953 J. D. woon 2,660,635

AIR OPERATED CIRCUIT BREAKER Filed Dec. 8, 1948 5 Sheets-Sheet 5 IN VENTOR.

ATTORNEYS.

Patented Nov. 24, 1953 AIR OPERATED lCIRCUIT BREAKER Joseph D. Wood, Strafford Village, Pa.,

to I-T-E Circuit Breaker Company,

assigner Philadelphia, Pa., a corporation of Pennsylvania Application December 8, 1948, Serial No. 64,085 4 Claims. (Cl. ZOU-81.5)

My present invention relates to circuit breakers and more particularly to a portable air operating system for use in connection with a circuit breaker and especially for use in connection with a mult1- plicity of circuit breakers wherein the portable air operating system may be attached and detached to the particular circuit breaker which 1t is desired to operate.

Primarily, my invention is directed to auxlhary means to close circuit breakers if for any reason the mechanical or electrical operating means for closing the circuit breaker fails to operate.

If for any reason in the case of solenoid closing breakers the solenoid should fail to operate, it is desirable and in many cases necessary to eliminate the need for an operator to close the breaker manually against a possible short circuit.

My invention contemplates extending the guide tube for the solenoid plunger or armature downwardly in order to form a cylinder in which the solenoid plunger or armature comprises the piston.

A connection is made to the end of the guide tube through a convenient tube or pipe to the opposite end of which a compressed air source may readily be attached when desired. Admission of compressed air into the guide tube will force the solenoid plunger up, thereby operating the circuit breaker to the closed position.

Accordingly, the primary object of my invention is the provision of novel air operating means for a circuit breaker.

Another object of my invention is the provision of auxiliary air operating means for a circuit breaker.

Another object of my invention is the provision of auxiliary operating means for a circuit breaker utilizing the solenoid armature as a piston and its guide tube as a cylinder in an auxiliary compressed air system.

Another object of my invention is the provision of novel air operating means for a circuit breaker which may be made portable and movable from circuit breaker to circuit breaker in a switchboard or a multiplicity of switchboards.

The foregoing and many other objects of my invention will become apparent in the following description and drawings in which:

Figure 1 is a View in perspective showing the manner of use of my novel portable compressed air system.

Figure 2 is a schematic view showing the operation of my novel auxiliary compressed air operating system in connection with a specific solenoid operating circuit breaker.

Figure 3 is a schematic view showing the utilization of my novel compressed air operating system as the primary operator for a circuit breaker.

Figure 4 is a view in perspective of the type of circuit breaker used in Figure 1.

Figure 5 is a detailed vertical cross-section of the solenoid closing mechanism of the circuit breaker of Figure 4.

Figure 6 is a bottom View of the solenoid housing cover of Figure 5.

Referring lirst to Figure 1, I have here shown a tank I al having a supply of compressed air with an outlet pipe controlled by the hand operated valve E2. Pressure gauge I 'i indicates the operating pressure available for use in the hose I I. The tank Hi may be mounted in any suitable manner for movement from breaker to breaker in the switchboard I3.

I have here shown one method of mounting the tank by means of angle brackets I4 on cross bars iii which carry the wheels I6. The switchboard I3 comprises a plurality of circuit breaker compartments I8, I9, 2li, 2|.

Compartment 2i houses a large truck mounted circuit breaker indicated generally at 22 of the general type disclosed in application Serial No. 757,356, iiled June 27, 1947, now Patent No. 2,611,838, and application Serial No. 720,561 led January 7, 1947, now Patent No. 2,601,417. Compartments I8, I9, and 2i) house smaller circuit breakers.

Compartments 23v and 24 may contain other apparatus necessary in a switchboard as, for instance, a transformer or a switchgear.

Each of the circuit breakers in compartments I8, I9, 2li, and 2i is provided with a pipe 25 which 1s preferably flexible and which is connected from the circuit breaker to the coupling 25 mounted in the front door of each of the respective compartments.

.The function of the preferably flexible pipe 25 will be hereinafter more specically described.

The hose Il from the compressed air source I0 is provided with the matching coupling member 28 to interengage with coupling 26 of hose 25,

Assuming that each of the circuit breakers is operated to closed position by a solenoid closing coil and assuming that one of the solenoid closing coils is inoperative for any reason lwith the circuit breaker open, then the portable compressed air supply I may be utilized to reclose the circuit breaker without requiring that the operator approach the circuit breaker closing.

The operator moves the tank I0 to a position where the hose coupling 28 of hose II may be connected to coupling 26 of pipe 25. After making this connection, he then returns to the tank |0 which may be located 'at a remote .point as determined by the length of hose and turns the valve operator |2 to lead compressed air from the tank IIJ through pipes II and 25 to the circuit breaker operating the circuit breaker to closed position.

Should the, circuit breaker close on a short circuit, then the ope-rater being at a remote point operating the valve `|2wil1 be in a much safer position than if he had attempted to close the circuit breaker manually.

The degree of safety will, of course, be determined by the length of the flexible hose which may be made long enough to provide absolute safety under all conditions.

As hereinafter pointed out, the utilization of the movable tank |6 and hose |I requires only minor modication of existing circuit breaker structure; that is, it'would only be necessary to lengthen the guide 4tube for the solenoid plunger to make -su're that the solenoid plunger is a piston-like fit in the guide tube, seal the bottoni of the gui-'de tube leaving an opening to which the hose 25 may be connected and to connect the hose 25 to the coupling 26 which may be connected to the door ofthe compartment.

This change injexisting solenoid operated circuit breakers requires a minimum of material and but an hou'r or two -of time. Consequently, the installation of the auxiliary compressed air yoperating system for utilization in `connection with many circuit breakers and even many switchboards requires 4only the single portable tank l0 and its hose and the slight `change in each of the circuit breakers above mentioned `and hereinafter described.

While my invention, lof course, lends itself to permanent installations, the utilization of a portable tank and flexible hose II or at least the utilization of the detachable and attachabl'e construction of hose y|| in connection with each of the hoses 25 is much simpler andl far more economical than a plurality of parallel permanent 'compressed air pipe lines.

In Figure 2 I have shown the modification that may readily be made Ia circuit breaker in rorder to enable my novel auxiliary compressed air system to operate.

The `circuit breaker is of the type disclosed in application serieu No. 720,561, nled January 7, 194'?, now Patent No. '2,601,41'1, Aand is of the type described therein as a blow-open, blowelosed circuit breaker; that is, the closing movement andjust as the contacts engage, but before they have fully engaged, the current loop through the elements provides a'blow-closed effect, When the circuit breaker is tripped, the elements are so arranged lthat the current loop provides a blow-open effect.

The circuit breaker ||0 `is supported Am any suitable manner on a panel IH, Carrying additional supporting brackets, not shown, to support the various pivot pins hereinafter described.

The back panel I I I carries an upper back connection stud H5 and a lower back connection stud ||6, mounted in any suitable insulators 2 I5 and 2I6. The upper back connection stud ||5 carries at the end thereof a stationary contact structure Movable contact arm |25 carrylng movable contact |26 and arc horn |21 is pivotally mounted on the pin |28 which passes through the arcuate horizontally extending slot |29 in extension |3| of the lower back connection stud H6.

Highly conductive inserts |34 on either side of the extension I3I ensure good current conducting engagement between contact arm |25 and the extension I3I.

Arm |25 is a double arm, the elements of which are mounted on opposite sides of extension I3I and pressed by spring washers against conductive inserts |34.

The current path established when the contacts' are closed is thus from the upper back connection stud ||5 to the stationary contact structure ||1, then through movable Contact |26 and movable contact arm |25 tothe extension 13| of the lower back connection stud ||6 and then to the lower back connection stud ||6.

It will thus be seen that when the contacts are closed, a U-shaped current loop is established with the contact elements ||1|26 at yone of the bends or corners of the loop.

` The movable contact |25 is held closed during the 'operation of the circuit breaker by the toggle |52, 'one link |53 of which is connected to the pin |50 on contact arm |25, the opposite end Aof the link |53 being Iconnected to the knee pin 4| 55 of the toggle |52.

The other link |54 of the toggle |52 is `connected at one end to the knee pin |55 and is pivoted at the other end on the stationary pin |51. Link |54 has 'a downward extension |62 which Awith link |54 forms a bell crank lever IBI-|62. Roller l|63 secured at the end 'of link |62 is engaged in detent |64 'of latch |65.

When the overload trip kcoil |1| is energized, the armature |12 is raised 'against 'extension l|61 of latch |65 causing the latch |65 to pivot counterclockwis'e about 'the stationary pin |66 sothat the detent |64 thereof disengages roller |63 and the toggle |52 Amay break `downwardly to 'open the circuit 'breaker as shown in .Figure 2.

During the closing operation the 'possible movement of the toggle 'upwardly through 'center is prevented bythe cross-bar or 'stop ITU above the knee pin |55. When the toggle |52 has broken downwardly, thus permitting the contact |25 to be forced open .by the blow-open eiect, the knee pin |55 drops and roller 63 rises. Roller V|63 is connected to the link |15. Link |15 is provided at its outer left-hand end with .a-slot |16 in whichrides the vpin |11. Pin |11 is connected to the upper Iend of the bell crank liever latch |18 which is .fpivoted on the pin |19.

Latch |16 has a vdetent II-80 lwhich engages roller |8| on the closing farm |82. rArm :|82 is .pivotally mounted -on the pin |63 and is biased toward the right into clockwise movement by the compression spring |84.

`When now the roller |63 rises up toward the left, on opening of the contacts, the link 15 is driven tothe left rapidly and when the end |16a of the slot |16 strikes pin 111, latch v| 18 ,is given a hammer blow in 'a -coun-terclockwise direction to disengage the detent from roller |8|.

;is pushed up,

the'compression spring 44 aids in maintaining the valve 4l against its seat on the valve opening 40.

As the upper limit Yof travel of member 3c is reached, the collar 454 on valve rod 42 strikes against the abutment 46 at the .bottom of member 30 and the valve rod 42 and valve 4| are pulled upwardly opening the exhaust opening 40.

By this time, the toggle |90 has been extended to close the circuit breaker or other closing apparatus has been operated to the full closed position of the circuit breaker, and no further rise of the solenoid armature-piston is needed and, of course, no further build-up oipressure in chamber :i4 is desired. Further building up of pressure is, however, avoided by the automatic opening of the valve 4l.

By this means, therefore, a simple modification of existing circuit breaker construction makes possible the utilization of auxiliary remote control air operating means for closing a circuit breaker without interfering with the electrical operation thereof.

If, for any reason, the solenoid mechanism should go out of order, the operator need not take the risk of manually closing the circuit breaker on a possible short circuit but need merely wheel the tank ||l to a position where the hose may be attached to hose 25 and then standing tar enough from the circuit breaker to be safe he need merely voperate valve I2v to close the breaker.

If a short circuit does exist resulting in immediate reopening of the circuit breaker with the attendant possibly dangerous arc, the operator is suinciently remote from the circuit breaker and its compartment to be safe.

Where a single unit is to be available to operate many circuit breakers, it may even be desirable to fix the air tank and especially the valve operator |2 at some position sufficiently remote from all circuit breakers so that the operator turning the valve I2 at that position will be absolutely safe, and then a hose il of sufficient length may be provided so that it may be connected to any oi the circuit breakers which are to be operated by the auxiliary air system.

Such a stationary system for use in a large installation requires, however, its own air compressor and other auxiliary means for ensuring a vcontinuous supply of air at full pressure. In a small sub-station, the added cost of an air compressor may not be warranted, especially since the occasions when a solenoid coil will fail to operate will be very rare.

Accordingly, the installation should be so arranged that it will not be expensive. For this reason, a simple drum may be used for the tank l and it may be mounted in simple fashion on wheels or even a dolly to be readily portable.

In a very small unit, the tank may even be filled by a hand pump or the tank may from time to time be taken down to a conveniently located power pump to be refilled.

In Figure 3 I have shown a modification of. my invention so that it may be utilized as the primary means for closing a circuit breaker rather than as an auxiliary means.

AIn this case, the solenoid coil |99 is dispensed with, and the guide tube 3| is the closing cylinder. Otherwise, all* of the elements operate as previously described in connection with Figure 2, but there is no. solenoid operated closing mechanism..

When it is desired to close the circuit breaker,

hose is connected to hose and air isadmitted to chamber 34a below the piston 30a to operate the piston upwardly in the manner previously described. All other elements of the air system as weli as of the circuit breaker may be identical.

While in the circuit breaker here disclosed I have not shown manual closing means, it will be obvious that a handle attached to link |91 or" toggle la may be utilized to close the circuit breaker manually for test purposes but since the possibility that short circuit may exist still remains when the circuit breaker is in the operative position, the auxiliary air system here disclosed may be utilized with absolute safety by the operator I to close the circuit breaker even on a short circuit.

In Figure 4 I have shown in perspective a standard circuit breaker 22 of the type shown in Figure l and well-known in the art, the circuit breaker being provided with the solenoid housing 5l) shown in greater detail in Figures 5 and 6. The solenoid mechanism in housing 50 acts as the operating means for closing the circuit breaker.

Solenoid core 5ft acts as a piston, travelling from the dotted line position 55 to the solid line position 5S to drive the plunger 52 upwardly to close the circuit breaker. rhe solenoid coil normally drives the core 54 upwardly. When it is desired to utilize iiuid pressure to drive core Fifi upwardly to close the circuit breaker, pipe 25 is attached to the tapped opening 53 in solenoid housing cover 5d to admit iiuid under pressure below the core 5d. The operation for closing the circuit breaker is then identical' with that described in connection with Figures i to 3.

While in the foregoing I nave disclosed a specie type oi circuit breaker in which a toggle is extended to close the contacts, it will be obvious that this system is applicable as well to all other types of circuit breakers.

The system of Figure 2 may be utilized in ccnnection with any solenoid operated circuit breaker, and the system of Figure 3 may be utilized in connection with any type of circuit breaker whether manually or solenoid operated.

The circuit breakers in connection with which my invention is used may have manual closing means, solenoid closing means or even special air operated closing means. My auxiliary air operating system may be utifced in connection with any of these closing means or a substitute therefor where closing the circuit breaker manually is dangerous, where the closing solenoid is out of order for any'reason, or where the normal air operated closing system is out of order for any reason.

In the foregoing I have described my invention solely in connection with specific illustrative embodiments thereof, Since many variations and modifications of my invention will now be obvious to those skilled in the art, I prefer to be bound not by the specific disclosures herein contained but only by the appended claims.

I claim:

l. In a circuit breaker having a pair of cooperable contacts, an electromagnet having an armature, mechanism controlled by said armature for operating said contacts into engagement,.a chamber for said armature, said armature forming a piston in said chamber, and a source of iiuid pressure connectable to said chamber for operating said contacts into engagement.

2. In a switchboard, a plurality of circuitV breakers, a compartment individual to each of said circuit breakers, each'of said circuit break- The compression spring |84 is now in a position to drive the arm |82 clockwise around the pivot |83. This results in the movement of the parts to the condition wherein the closing toggle I9l has collapsed and in which the adjustable stop member |9| at the upper end of the arm |82 strikes the extension |52 or the link |4 rotating link |54-I62 in a counterclockwise direction to reextend the toggle |52 once more and to re* engage the roller I3 in detent lifi of latch |65.

The re-setting or extending of the toggle |52 does not at this time, however, result in closing of the circuit breaker, since pin |85 on arm |82 which is connected to arm |62 moves the arm I6I to the right, thus moving the pin it@ at the lower end of contact arm |25 to the right. This moves the pin |25 of the contact arm |25 to the right-hand side of the slot |29 but at the same time pushes the pin |55 over suiiiciently so that the contact arm continues to rotate outwardly toward the left around pin |28 which is held by the right-hand end of slot |29. Thus, even though the latch |535 is re-set, the circuit breaker remains open.

The closing toggle i B is prevented from breaking upwardly by the stop |95. Toggle |90 comprises a link |93 connected by pin |94 to the closing arm |82 and connected at the other end to the knee pin |56. Link lill is connected at one end to knee pin |95 and at the other end to the stationary pin |98. Closing solenoid ISES is provided with the armature 20d.

Now when the circuit breaker is in the open position with the latches all re-set, the contacts may be closed by energization or" the solenoid coil |99. On such energization the armature 2th? is raised to extend the toggle Hill. When the toggle I 90 is thus extended, closing arm |52 is rotated counterclockwise to the left about pin |83. This compresses the spring |84 and moves the arm 82 over to the left until latch |13 engages roller IBI on the arm IM. At the same time the movement of arm I 82 to the left `pulls the arm |6| to the left, thus pulling on pin Idil and causing the contact arm |25 to rotate in a counterclockwise direction around the pivot pin I.

Spring |54 is provided only to re-set, the toggle |52 and consequently is a relatively light spring so that it does not interfere with the closing of contacts as would be the case where opening springs are used. Thus, the mechanical force needed to close the contact is only necessary to overcome the inertia of the parts and the relattively slight force of the re-setting spring |84.

The contacts are driven home once they are initially engaged by the blow-closed effect above described. In fact, the closing coil and armature, as hereinafter pointed out, are aided by the arrangement of the parts which produce a net blow-closed effect during closing.

Also, the travel which is given to the closing coil and plunger 2D!) need merely be suilicient to complete the closing operation and no over-travel need be provided to provide any hammer blow or kinetic eiiect to slam the contacts home. The parts may thus be made lighter and at the same time, owing to the utilization of the electromagnetic forces to close the contacts rather than sheer mechanical force or kinetic energy, the parts are more durable.

Thus far, one type of circuit breaker in connection with which my invention may operate has been described. rihis circuit breaker has been described specifically so that a complete operative system may be shown,

' It will be obvious, however, from the following that any circuit breaker with a solenoid closing coil may readily be adapted to utilize the principles of my invention and, in fact, any. circuit `breaker may be operated Whether or not it has a solenoid closing coil in accordance with the principles oi my invention.

Referring again to Figure 2, the closing plunger 200 is, as was previously pointed out, operated by the armature 3|) or" the solenoid coil |99. The armature 3G operates in the guide tube 3|.

In accordance with my invention, the guide tube 3| which is normally only slightly longer than the coil IQS is extended downwardly to form a cylinder. The bottom of the guide tube is sealed by wall 32. The pipe or ilexible hose 25 is connected to opening 33 in the bottom Wall 32 so that air may be admitted to the chamber 34 oi the guide tube 3| below the armature 30 which is a piston-like iit in the guide tube 3 I.

When air is thus admitted, as previously described, from tank IO through hose I|, couplings 28 and 26, pipe 25, and opening 33 to chamber 34, compressed air forces the armature 30 which now acts as a piston to force the plunger 20E) up, extending the toggle and closing the circuit breaker.

This is the only modincation that is essential in order to adapt the circuit breaker to the utilization of my novel auxiliary system.

After the circuit breaker is closed. however, the various latches above-described hold it closed and it is no longer necessary to support the armaturepiston 30 by air or other means.

It may in certain circumstances be desirable, in fact, to lead oi the air in chamber 34 to prevent excess pressure in the guide tube 3|. That is, in order to utilize the tank for many operations Without the necessity for recharging it frequently, it may be desirable to charge the tank I0 to a pressure much higher than that which is necessary actually to close a particular circuit breaker.

When the valve I2 is opened, the pressure builds up quickly in chamber 34 of the guide tube to force the piston-armature 30 up as the pressure increases. After the armature 30 has been forced up to close the circuit breaker, no further build-up of pressure is needed or even desired.

Hence, it is desirable to provide an exhaust valve in the guide tube 3| so that pressure will not build up too high therein. rI'he operator who turns the valve can thus watch the appropriate indicator on the switchboard and when it hasy shifted from open to "closed, then he need merely close the valve I 2.

Where an exhaust valve is provided in the guide tube, then lower pressures must be used in guide tube is needed, or the operator must be very skillful and quick in operating the valve |2U to close the same the moment the circuit breaker As the armature-piston 3|);

ers having a pair of cooperable contacts, an electromagnet having an armature, mechanism controlled by said armature for operating said contacts into engagement by either electrical or hydraulic influence, a chamber for said armature, said armature forming a piston in said chamber.

3. In a switchboard, a plurality of circuit breakers, a compartment individual to each of said circuit breakers, each of said circuit breakers having a pair of cooperable contacts, an electromagnet having an armature, mechanism controlled by said armature for operating said contacts into engagement, a chamber for said armature, said armature forming a piston in said chamber, a portable source of iuid pressure connectable to said chamber for operating said contacts into engagement, and means :for selectively making said connection from said source to any one of said circuit breaker mechanisms.

4. In a circuit breaker having a pair of cooperable contacts, an electromagnet having an armature, mechanism controlled by said armature for operating said contacts into engagement, a cham- 10 ber for said armature, said armature forming a piston in said chamber, a source of fluid pressure connectable to said chamber for operating said contacts into engagement, a normally closed eX- haust vent, and means operated as said contacts are operated into engagement for opening said vent to drop the pressure in said chamber.

JOSEPH D. WOOD.

References Cited in the file of this patent UNITED STATES PATENTS

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