US2225055A - Circuit interrupting means - Google Patents

Description

Dec. 17, 1940 P. B. HOYE CIRCUIT INTERRUPTING MEANS Q SheetS-Sheet 1 Filed Feb. 1, 1937 Dec. 17, 1940. P, B, HOYE, 1 2,225,055

CIRCUIT INTERRUP'IING MEANS Filed Feb. 1, 19:57 9 Sheets-Sheet 2 I Zia/@7750)":

(Bay fade/15156 70 Dec. 17, 1940. HOYE 2,225,055

CIRCUIT INTERRUPTING MEANS Filed Feb'. 1, 1937 9 Sheets-Shget 3 Dec. 17', 1940. P; B. HOYE cmcum INTERRUPTING MEANS Filed Feb. 1, 1937 9 Sheets-Sheet 4 C //PC 0/ 7 BREAKER ChQCU/ BE Dec. 17, 1940. P. B. HOYE 2,225,055

C IRCUIT INTERRUPTING MEANS Filed F'eb.- 1, 19:57 9 Sheets-Sheet 5 Dec. 17, 1940. HOYE 2,225,055

CIRCUIT INTERRUPTING MEANS Dec. 17, 1940. p HQYE 2,225,055

CIRCUIT INTERRUPTING MEANS,

Filed Feb. 1, 1937 9 Sheets-Sheet 8 2y W I Dec. 17, 1940. HQYE 2,225,055

CIRCUIT INTERRUPTING MEANS Filed Feb. 1, 1937 9 ShevtsSheet 9 fig .14! 50 fax/aw)".-

Patented Dec. 17, 1940 UNITED STATES.

PATENT OFFICE CIRCUIT INTERRUPTING MEANS Application February 1, 1937, Serial No. 123,325

11 Claims.

My invention relates, generally, to electric circuit interrupters or circuit breakers, and has particular relation to the construction and operation thereof.

In order to electrically close a circuit interrupter or circuit breaker, operating devices in the form of solenoid mechanisms and electric motor mechanisms are employed. The solenoid mechanisms are provided with armatures, while the motor mechanisms are arranged to operate either directly or through suitable reduction gearing. On energization of one of these mechanisms, the contact members of the circuit breaker are operated to the closed position through a suitable linkage and they are held in this position by various types of latching or holding devices. On release of the latching or holding device, the contact members are permitted to move to the open position under the biasing force of gravity or of suitable springs or weights, or a combination of these biasing forces in order to quickly extinguish any arcs that may be drawn by separation of the contact members while carrying current.

Accordingly, the object of my invention, generally stated, is to provide a circuit interrupter or circuit breaker and operating means therefor which shall be simple and .efficient in operation, and which may be readily and economically manufactured and installed.

It is necessary to provide some means for deenergizing the operating device on closure of the circuit breaker. However, it is equally essential to maintain the operating device energized until the circuit breaker is operated to the fully closed position where it can be held closed by the latching or holding device. When it is recalled that the circuit breaker is closed with considerable force by the operating device and severe shocks and vibrations result, it will be appreciated that a rugged and reliable cut-off mechanism must be provided to effect the deenerg'ization of the operating device at the proper time.

4 In view of these requirements, an important object of my invention is to provide for deenergizing the operating device employed for closing a circuit breaker at the proper instant when the circuit breaker is operated to the closed position,

50 and which shall not require close adjustment.

Another important object of my invention is to provide for deenergizing the operating device of a circuit breaker at the proper instant without opening the control circuit therefor.

55 Another important object of my invention is to combine the cut-off mechanism of a circuit breaker with the holding or latching mechanism in such manner as to deenergize the operating device used for moving the contact members of the circuit breaker toward the closed position at the 1 proper instant and to effect the final movement of the contact members by the cut-off mechanism, thereby rendering unnecessary an exact timing of the deenergization of the operating device.

In many industrial applications of electric 10 power, the continuity of power supply is of utmost importance. In the event of a failure of the power supply, valuable time may be lost through the enforced shut-down of electrically driven machines and the like. Also, in some industries, such as those in which electric heating devices and electric furnaces are used, a failure of power supply may cause a loss in material being processed or such change in the material being processed as to render it worthless. In such installations, an auxiliary or emergency power circuit is provided to which the load circuit can be transferred on failure of the main or preferred power circuit. Therefore, another object of my invention is to provide for quickly and automatically transferring a load circuit from a preferred power circuit to an auxiliary power circuit on the occurrence of a fault, such as failure of power, on the preferred power circuit.

A further object of my invention is to provide for automatically transferring the load circuit back to the. preferred power circuit as soon as the fault on it is removed.

Still another object of my invention is to interlock the control circuits of the circuit breakers employed to effect this transfer in such manner as to prevent the simultaneous closure thereof.

A further object of my invention is to interlock the holding or latching and cut-off devices of the circuit breakers in such manner as to pre- 0 vent this simultaneous operation.

Where transfer circuit breakers are provided for connecting a load circuit to an auxiliary power circuit when the main or preferred power circuit fails, it may be desirable in some cases to interconnect the main and auxiliary power circuits. The auxiliary power circuit may form a part of a power system to which other load circuits may be connected. On failure of power on the auxiliary circuit, these load circuits are, of course, deenergized. However, they can be energized by simultaneously operating both of the circuit breakers which normally are employed for transferring the main load circuit from the main power circuit to the auxiliary power circuit. The reverse operation may also be true and it may be desirable to supply power to the main power circuit from the auxiliary power circuit by a simultaneous operation of both of these circuit breakers.

Thus, another object of my invention is to provide for automatically transferring a load circuit from a main to an auxiliary power circuit on failure of the main power circuit for example, and for interconnecting the two power circuits under certain operating conditions.

On the occurrence of a fault on a power circuit, such as a short circuit, the circuit breaker which is provided for connecting it to a power source is immediately opened by suitable fault responsive relays to clear the system of the fault. Operating experience indicates that faults of this nature are temporary, and clear themselves in most cases within a very short time. The circuit breaker can, therefore, be immediately reclosed and continuity of power substantially maintained despite its temporary interruption. In such case it is highly desirable that the circuit breaker be immediately reclosed with a minimum outage time for the circuit. This time is comparatively short and is of the order of a fractional part of a. second or a few cycles, for example three or four, in a 60-cycle system.

0 Therefore, a further object of my invention is to immediately reclose a circuit breaker that has been opened because of the occurrence of a fault on the circuit in which it is connected.

Another object of my invention is to open the 5 energizing circuit of a variable impedance device, that is used to control, the functioning of a circuit breaker operating device and to hold it closed, upon the occurrence of a fault to immediately initiate the reclosure of the circuit breaker within a fractional part of a second.

As set forth hereinbefore, when a circuit breaker is closed, a considerable shock is experienced when the movable contact members are operated to the closed position. The fixed or stationary contact members, cooperating therewith, are ordinarily mounted in tubular insulators which, in turn, are mounted in the circuit breaker housing. Rod-like conductor members extend through the tubular insulators to connect the stationary contact members with external bushings and the external circuits. Considerable difficulty has been experienced in obtaining a satisfactory means for securely holding the rod-like conductors in the insulators because of the shock and vibrations that are set up on closure of the circuit breaker.

Therefore, an ancillary object of my invention is to provide a resilient connection in the external bushing nut between it and the insulator in engagement therewith.

Other objects of my invention will, in part, be obvious and in part appear hereinafter.

My invention, accordingly, is disclosed in the embodiments thereof shown in the accompanying drawings, and it comprises the features of construction, combination of elements and arrangement of parts which will be exemplified in the constructions hereinafter set forth, and the scope of the application of which will be indi- O cated in the appended claims.

For a more complete understanding of the nature and scope of my invention, reference may be had to the following detailed description taken r in connection with the accompanying drawings,

0 in which:

Figure 1 is a View, in side elevation, of my novel circuit interrupter and operating mechanism therefor, the housing being shown in section;

Figure 2 is a detail sectional View, taken generally on the line 2-2 of Figure 1;

Figure 3 is a sectional view, taken along the line 33 of Figure 1;

Figure 4 is a detail sectional View, taken along the line 4-4 of Figure 5, the motor being shown in outline only;

Figure 5 is a sectional View taken along the line 5-5 of Figure 1;

Figures 6 and '7 show different operating positions of the linkage that is employed in interconnecting the motor and the movable contact members of the circuit breaker;

Figure 8 illustrates, diagrammatically, the general arrangement of my novel reclosing circuit breaker system and connections for simultaneously operating both of these circuit breakers to provide an interchange of power between .the main and the auxiliary power circuits;

Figure 9 illustrates, diagrammatically, the circuit connections that may be employed in practicing my invention in conjunction with the circuit diagram shown in Figure 8;

Figure 10 illustrates, diagrammatically, a mod ified circuit arrangement for controlling the transfer system which may be employed in lieu of the circuit connections shown in Figure 9;

Figures 11 and 12 illustrate, diagrammatically, modified arrangements of my novel circuit interrupting means;

Figure 13 illustrates, diagrammatically, how my invention may be embodied in a control system that is energized with direct rather than alternating current; and

Figures 14 and 15 illustrate the novel features of my circuit interrupter as applied to a reclosing circuit breaker system.

According to my invention, I provide for closing a circuit breaker through a suitable linkage by means of a torque motor that is arranged to operate through a partial revolution. It will be understood, however, that other suitable energy translating devices may be employed instead of a torque motor. Since a preferred embodiment of the invention employs a motor of this type, the functioning of my novel circuit interrupter will be set forth in connection therewith.

The torque motor is energized by operation of a suitable control relay which serves to connect it for energization to a suitable current source, such as a source of alternating current. The winding of the control relay is connected for energization through a winding on a core that has associated therewith an armature which is connected to the linkage and moves together with the movable contact members of the circuit breaker. When the circuit breaker is in the open position, the armature is positioned away from the core, and therefore, the impedance of the winding thereon is relatively low. On energization of the relay winding and the winding on the core connected in series circuit relation therewith from a source of alternating current, the control relay is first operated to effect the energization of the torque motor. As the armature approaches the core, the impedance of the winding thereon increases until, at the time that the circuit breaker is closed, the current flowing therethrough and through the relay winding is insufficient to maintain the relay in the operated condition. As a result, the torque motor is deenergized. Sufficient current, however, continues to flow through the winding on the core to hold the armature in engagement therewith. The circuit breaker is thus held in the closed position as long as the winding on the core remains energized. As soon as this winding is deenergized, the armature is no longer attracted to the core, and the movable contact members of the circuit breaker are released for operation to the open position.

Generally speaking, the armature and core, and the winding thereon perform three functions. As

the movable contact members approach the closed position, the attraction of the armature to the core is sufficient to effect the final movement thereof, and thus the torque motor is relieved of operating them to the final position. It is, therefore, unnecessary to provide an. exact control for the time when the torque motor is deenergized. The second function that is performed is the holding of the circuit breaker in the closed position until the winding on the core is deener gized. The third function is the deenergization of the relay winding to such an extent that its contact members are opened to disconnect the torque motor from its energizing source. It will now be obvious that I have provided a simple and efficient means for controlling the functioning of a circuit interrupter which does not depend for its operation upon the opening of carefully positioned limit switches and the functioning of mechanical latches to deenergize the circuit breaker operating mechanism and to hold it in the closed position.

Various embodiments of the foregoing generally described circuit breaker or circuit interrupter will be presently set forth, together with an indication of the manner in which my invention may be employed in connection with a system for transferring automatically a load circuit from a main power source to an auxiliary power source in the event of a fault on the main power source. In addition, my invention will also be illustrated in connection with a reclosing circuit breaker system that is employed for immediately reconnecting a circuit to a power source after a temporary fault thereon has been cleared.

Referring now particularly to Figures 1, 2, 3, 4, and 5, it will be observed that the reference character 2B designates, generally, a circuit interrupter having a housing 2| through the upper side of which insulator bushings or tubes 22 extend for supporting stationary contact members 23 in insulated spaced relation. A four pole circuit breaker has been illustrated for use in connection with a three phase four-wire circuit, but it will be understood that my invention may be practiced by using a circuit breaker having a different number of poles for connection in a different circuit. Movable contact members. 24, carried by rods 25 of insulating material, are provided to bridge the pairs of stationary contact members 23. 'The rods 25 are carried by a common support member 25 which is channel-shaped, and to which is secured a pair of upstanding ears 2'! between which a lever 28 is positioned and secured thereto by a pin 29. The other end of the lever 28 is secured by a pin 3|! between a pair of support plates 3! that are suitably secured to the upper surface of a top plate 32, which in turn is suitably mounted in the housing 2 I. The contact members 24 are arranged to move to the position shown bythe broken lines in Figure 3 of the drawings under the influence of gravity, and are arranged to be operated into engagement with the stationary contact members 23 by movement of the lever 28 about the pin 35 as a fulcrum by means which will be presently described.

In order to movethe lever 28 upwardly about the pin 30 as an axis, a pair of toggle joints is provided. An additional toggle joint is provided for cooperating with the first two toggle joints to hold the movable contact members 24 in the closed position. These toggle joints comprise what may be generally described as a linkage.

The first toggle joint includes a pair of flat links 35 that are secured to the lever 28 by a pin 35 at one end. At the other end the links 35 are secured by a pin 31 to an arm 38 of a cast steel operating member 39 which is rotatably mounted on a transverse shaft 45! that extends between frame plates 4| and 42 that are secured to and depend from the top plate 32, as illustrated more clearly in Figure 2 of the drawings. Integrally formed with the operating member 39 is a pair of arms 43 between which a link 44, forming a part of the second toggle joint, is secured by a pin 45. Pivotally mounted on. a pin 45, extending between the frame plate 4| and a frame plate 41 depending from the top plate 32, is a bellcrank 48, one arm of which forms the complementary part of the second toggle joint. The bellcrank 48 comprises a pair of spaced. arms between which one end of the link 44 is positioned and secured thereto by a pin 49. A roller 55 is mounted on a pin 5| extending through the two members forming the bell crank 48 for a purpose which will be presently set forth.

By means of a pin 52, the third toggle joint is connected to the other arm of the bellcrank 48. This toggle joint comprises a link 53 which is secured by a pin 54 to a socket member 55 that,

in turn, is pivotally mounted on a pin 55 extend ing between the frame platesv 4| and 41. The socket member 55 is provided with a socket 51 into which an operating lever may be inserted for manually operating the circuit breaker.

With a View to holding the circuit breaker in the closed position, a link 53 is connected at one end to the pin 54 of the third toggle joint, and, at the other end, by a pin 59 to the tail piece 65 of an armature 6 I which is pivotally mounted on a pin 52 that is carried by a core 63. core 63 is mounted on the frame 2 i in any suitable manner, and has provided thereon a holding winding 64 which, on energization, serves to attract the armature 6| to the core 63. However, the force that is exerted by the holding winding 64 is not suflicient to attract the armature 6| to operate the movable contact members 24 to the closed position. from the full open. position, but it is sufficient to effect the final closure thereof and to hold them closed when the armature 6| is in close proximity to the core 63. Therefore, it will be understood that the armature 6| is movable through the agency of the three toggle joints, together with the movable contact members 24.

As illustrated in Figure 1 of the drawings, the circuit breaker 20 is in the closed position. In this position, the third toggle joint comprising the link 53 and the socket member 55 are nearly in alignment. That is, the pins 52, 54 and 56 are very nearly positioned in a straight line. Therefore, the force that is required to be exerted by the armature 5|, as attracted by the winding 64, is only that which is necessary to provide the slight component of the total force that is required to hold the movable contact members The 24 in the closed position. Moreover, when the holding winding 64- is deenergized, this slight component of force no longer exists, and the third toggle joint is no longer restrained. The movable contact members 24 are then free to move to the open circuit position.

The movable contact members E i are operated toward the stationary contact members 23 initially by a motor 68 that is suitably mounted in the frame 2!. The motor 83 is preferably a torque motor of the series type, the shaft til of which is rotated only through a partial revolution to efiect the movement of the contact members 24 from the open to the closed position. Mounted on the shaft 65% and for rotation therewith is a cam member 79. As illustrated, the cam member :0 is circular in outline and is eccentrically mounted on the shaft 69. A cut-away section ll is provided in the body of the cam member ill in order to so position the center of gravity of the cam member that it will be readily biased by gravity to the position shown in Figure 1 of the drawings as soon as the motor 68 is deenergized. A rubber bumper F2 is provided with a suitably curved surface, and is positioned in the path of movement of the cam member 19 as it is restored to its normal position to cushion the shock. The external surface of the cam memher It! is arranged to engage the roller 59 for operating the circuit breaker to the closed position. A circular opening 13 is provided in the frame plate 4! to permit inspection and adjustment of the linkage and the various parts cooperating therewith.

In Figures 6 and '7 of the drawings, I have illustrated the positions to which the linkage interconnecting the motor 68 and the movable contact members 24 is operated. Figure 6 shows the linkage with the circuit breaker closed, and Figure 7 shows the linkage with. the circuit breaker opened. In the latter position, it will be observed that the roller 58 is in engagement with the outer surface of the cam member Ill that is closest to the shaft 59. When the motor 68 is energized and. the shaft 69 rotates in a clockwise direction carrying with it the cam member Ill, the roller 5b is moved upwardly, thereby moving the second toggle joint formed by the link 44 and one arm of the bellcrank 58 toward its position as shown in Figure 6 of the drawings. At the same time, the first toggle joint formed by the links 35 and the operating member 39 is moved to the right to lift the lever 28. When the cam member 15 is rotated to the position indicated by the broken lines in Figure 6 of the drawings, the pins 45, 49 and it will nearly be in alignment as will be the pins 36, t5 and M].

only a small component of force is required to be exerted by the third toggle joint comprising the link 53 and the socket member 55 to hold the movable contact members 2 1 in the closed position.

By means which will be presently described, the motor B3 is deenergized as the cam member '40 approaches the position shown by the broken lines, and the cam member ill returns to its original position under the influence of gravity and is stopped by the rubber bumper 12. As long as the winding 64 remains energized and the third toggle joint is restrained by the armature 6|, the circuit breaker will remain in the closed position. On deenergization of the holding winding 6%, the armature 6| will be released, as previously set forth, thereby releasing the linkage and permitting the circuit breaker to be operated to the open position under the influence of gravity and under the influence of biasing springs, if such springs are employed.

With a View to limiting the travel of the movable contact members 24 in the open position, a boss 15 is provided on the upper end of the arm 38, as illustrated more clearly in Figure 4 of the drawings, and it is arranged to engage a wooden plug 16 that is carried at the right hand end of an adjustable stop member Tl. The left hand end of the stop member 11 is threaded into a suitable lug 18 that depends from the top plate 32 and is secured in the desired position by a lock nut '39. If it is desired to hold the circuit breaker in the closed position While the operating mecha nism is being repaired or adjusted, the lock nut l9 can be loosened and the stop member l1 rotated until the plug 16 engages the boss 15 in its position as shown in Figure 4. The holding winding 64 may then be deenergized without opening the circuit breaker.

As indicated hereinbefore, a considerable shock is experienced by the stationary contact members 23 on engagement therewith by the movable contact members 24. As a result of repeated impacts, the sealed connection between the stationary contact members 23 and the lower ends of the insulator bushings 22 may be broken. Moisture may then be permitted to enter the interior of the housing 2| and to contaminate the oil therein which surrounds the contact members and in which arcs are drawn when the circuit is opened under load. In order to insure that the sealed connection will not be broken, the construction illustrated more clearly in Figure 3 of the drawings has been provided.

As illustrated in Figure 3. one of the insulator bushings 22 has been shown in section. The stationary contact member 23 has connected thereto a rod-like conductor 82 that extends upwardly through the bushing 22 and has threaded on its upper end a bushing nut 83. A gasket 84 of a suitable compressible material is positioned between the lower end of the bushing 22 and the upper surface of the stationary contact member 23. As originally installed, the bushing nut 83 is turned on the upper end of the conductor 82 against a flange 85, integrally formed near the upper end of the bushing 22, compressing the gasket 84 and providing the desired sealed connection.

If the bushing nut 83 is formed as a solid member of copper and internally threaded, the desired sealed connection will be provided, merely by tightening the bushing nut 83.

jected to several impacts during operation, the gasket 8 becomes further compressed, and no corresponding tightening action takes place with respect to the nut 83 unless it is manually tightened. As a result, the sealed connection may be broken and moisture may enter as previously described.

With a view to automatically taking up this slight slack that is caused by the compression of the gasket 84, I have modified the lower end of the bushing nut 83 by providing an internal groove 85 near the lower end, and an external groove 8? immediately thereabove by a suitable turning operation. A certain degree of flexibility and resiliency is now provided in the lower end of the bushing nut 83 while still maintaining a complete engagement with the upper surface of the flange 85. When the bushing nut 83 is originally installed, it is tightened with sufficient eilort However, after the stationary contact member 23 has been subto compress the resilient lower end thereof slightly. Sufficient resiliency is thereby provided to maintain the sealed connection despite repeated tegrally formed fingers 88 that are surrounded by garter springs 89. A plug-like terminal member 90 is provided for interfitting between the fingers 88. A suitable opening Si is provided in the plug member 90 into which a circuit conductor may be secured, as by soldering, as will be readily understood. An insulator sleeve 92 surrounds the plug member 00, and extends over the upper end of the insulator bushing 22, as illustrated.

Thus far I have described in detail the construction and functioning of a circuit breaker which operates as a single unit. It will be understood that the circuit breaker may be arranged for individual operation in conjunction with a suitable control mechanism, and that it may be arranged to function in connectionwith a second circuit breaker of like construction for transferring a load circuit for energization from a main or preferred power circuit to an auxiliary or emergency power circuit. The latter type of arrangement will first be described with a view to illustrating the novel features .of my invention as applied to such a system.

When it is desired to insure a continuity of power on a load circuit, it is customary to provide an alternate or emergency power circuit in addition to the main or normal power circuit and to provide the necessary switching devices for automatically transferring the. load circuit from one power supply to the other as the case may be. The auxiliary or emergency supply circuit may form a part of a single generating system, and it may be so arranged-that it'would be unaffected by the occurrence of a fault on the main power circuit. Again, the auxiliary power circuit may be energized from an entirely separate source of power for the purpose of insuring the highest degree of reliability.

For the purposes of description, the alternate power circuit is described as an emergency or auxiliary power circuit. However, this circuit may be employed to supply other loads during the normal course of operation. In like manner, the main or normal power circuit may also be employed to supply other loads than the particular load under consideration which may be supplied fromeither power circuit. On the failure of power on either of these circuits, it may be desirable to provide for so operating the transfer switching equipment that either circuit may be energized from the other one so that all of the load circuits connected thereto may be energized. For this purpose I have provided the circuit arrangement and system that is disclosed diagrammatically in Figure 8 of the drawings.

As shown in this figure, a preferred power circuit, shown generally at 95, is provided comprising a neutral conductor N and line conductors A, B and C. While a three phase four-wire system is illustrated herein, it will be understood that other types of systems come within the scope of my invention. The preferred power circuit is connected by a circuit breaker 96 to a polyphase generator 91 which is arranged to generate a commercial frequency, such as 60 cycles. A load circuit .28 is arranged to be energized from the preferred power circuit at on operation of a circuit breaker 8S.

The auxiliary power circuit, shown generally at WI, and comprising a neutral conductor N and line conductors A, B and C, may be connected for energization by a circuit breaker I02 to a polyphase generator I03 that may be similar in its operating characteristics to the generator 91. A load circuit, shown generally at I04, may be energized by a circuit breaker I05 from the auxiliary power circuit IOI.

The reference character I516 designates, generally, a common load circuit comprising a neutral conductor N and line conductors A", B" and C which are arranged to be connected to the corresponding conductors of the preferred power circuit $5, or of the auxiliary power system IN by the operation of circuit breakers I01 and I08.

The circuit breakers 96, 99, I02 and I05 may be of the type disclosed herein, or they may be of any other suitable type, well known to those skilled in the art. I08 are preferably constructed as disclosed herein and controlled in the manner which will be presently set forth.

Under normal operating conditions, the common load circuit I08 will be energized from the preferred power circuit 95 as energized by the generator 97. For this purpose the circuit breakers 96 and I01 will be closed. In addition, the load circuit 98 will be energized when the circuit breaker 99 is closed. The load circuit I04 will be energized from the auxiliary power circuit IIlI when the circuit breakers I02 and I05 are closed.

Assuming now that some fault occurs in the generator 91 or the circuits connected thereto that may be cleared by opening the circuit breaker 96, the preferred power circuit 95 will be deenergized and the circuit breaker I01 will be automatically opened and the circuit breaker I08 will be automatically closed to transfer the common load circuit I06 for energization to the auxiliary power circuit IOI. If no further operation takes place, the load circuit 98 will be deenergized because of the deenergization of the preferred power circuit 95. However, if means are provided for closing the circuit breaker I01, which forms a part of the automatic transfer system, this load circuit 98 can still be energized, in this case, from the generator I03. In like manner, on failure of the generator I03, the circuit breaker I08 may be operated to maintain power on the auxiliary power circuit WI and to energize the load circuit I04. Thus, it will be observed that the transfer system may be arranged to serve a dual purpose; first, to maintain power on the common load circuit I06, and second, to maintain the load circuits connected to the preferred and auxiliary power circuits energized under certain operating conditions. It will be understood that the first function will be performed automatically while the latter function will be performed under manual control, since it is undesirable to interconnect the preferred and auxiliary power circuits when both of the generators 91 and I03 are operating because of the necessity of synchronizing them. However, as is well known to those skilled in the art, suitable synchronizing apparatus may be provided so that the generators 91 and I03 may be interconnected by operation of the circuit breakers I01 and I08, which form a part of the automatic transfer system. The control circuits for effecting the foregoing described operation of the circuit breakers I01 and I08 are illustrated in detail in Figure 9 of the drawings.

The circuit breakers I01 and In this figure I have illustrated the circuit breakers It! and I08 in diagrammatic form, together with the operating mechanism therefor, each of which is preferably constructed and arranged as shown in Figure 1 of the drawings and described hereinbefore. Insofar as practical, the same reference characters will be employed in order to indicate the various parts that are identical. The circuit breaker I8! is arranged to be closed by the series motor 68 having an armature 68A and a series field winding 68F. In like manner, the circuit breaker IE8 is arranged to be operated to the closed position by a series motor 68' having an armature 88A and a field winding SB'F. The motors 68 and 88' are arranged to be energized from power transformers H and III having primary windings H2 and H3 that are connected respectively for energization between the neutral conductor and one of the line conductors of the preferred and auxiliary power circuits 95 and IQI. The secondary windings H2 and I I5 of these transformers are commonly connected to a control bus H6, while the other terminals are connected to control busses H8 and Hi). In one commercial embodiment of my invention, the secondary windings II4 and H5 are arranged to supply a control voltage of 220 volts. Of course other control voltages may be employed if desired.

In order to effect the connection of the motor 68 to the conductors H3 and H8, a control relay I is provided having an operating winding I20w and make contact members I20a. In like manner, a control relay I2I is provided for effecting the energization of the motor 68. This relay is provided with an operating winding I2Iw and make contact members I2Ia. Single pole double throw switches I22 and I23 are provided for selectively connecting the motors 68 and 68 for energization to the control busses H8 and I! 9. When the switch I22 is operated to its upper position, the motor tllwill be energized from the conductors H8 and II8. When it is operated to its lower position, the motor 68 will be energized through conductor I24 from the conductors H6 and II9. Likewise, when the switch I23 is operated to its lower position, the motor 68 will be energized through conductor I25 from conductors IIS and IIE.

With a view to interlocking the circuit breakers I01 and H28 for the purpose of preventing simultaneous operation thereof, auxiliary break contact members Him and Iflia are arranged to be operated therewith. When the circuit breakers I01 and IE8 are in the open positions, these contact members are closed. However, on operation of one of these circuit breakers to the closed position, its auxiliary contact members are opened and the control circuit for effecting the energization of the other circuit breaker is normally held open.

As has been indicated hereinbefore, it is de sirable to provide for automatically transferring the load circuit I06 from the preferred power circuit 95 to the auxiliary power circuit MI in the event of a fault occurring on the preferred power circuit. This fault will ordinarily be of the nature of a loss of power on one or more of the phases. For the purpose of detecting the failure of voltage on one or more of the phases of the. preferred power circuit 95, voltage relays I28, I29 and I30 are provided, each of which is individual to one of the phases, as indicated. Each of the voltage relays is provided with break contact members I28a, I29a and I30a which are connected in parallel circuit relation for a purpose which will be apparent hereinafter. These relays are also provided with make contact members I281), I282) and I 30b. These contact members are connected in series circuit relation for a purpose which will also be set forth hereinafter. Operating windings I28w, I20w and I30w are provided which are connected for individual energization to the secondary windings I32, I33 and I34 of potential transformers I36, I3! and I38, the primary windings I40, I II and I42 of which are commonly connected for energization to the neutral conductor N and for individual energization from the line conductors A, B and C, as illustrated.

While voltage relays I28, I29 and I30 have been illustrated for connection to the preferred power circuit 95, it will be understood that a similar set of voltage relays may be provided and connected to the auxiliary power circuit IOI for the purpose of making this the preferred power circuit, if such operation is desired. However, since the illustration of these connections would mean merely a duplication of the connections already illustrated and described, and, further, since the connection thereof will be apparent to those skilled in the art, this additional feature has not been shown in detail herein.

For the purpose of interconnecting the preferred and auxiliary power circuits 95 and IOI,

control switches I44 and I45 are provided. When these switches are closed, as will be described hereinafter, the system will function as set forth hereinbefore in connection with the description of the circuit illustrated in Figure 8 of the draw- 7 mgs.

In describing the operation of the transfer system shown in Figure 9, it will be assumed that the preferred and auxiliary power circuits 95 and IOI are energized, and that the switches I22 and I23 are operated to their upper positions. It will also be assumed that the control switches I44 and I45 are in the open positions. Under these operating conditions, the windings of the voltage relays I28, I29 and I30 will be energized, thereby closing the make contact members I281), I291) and I302). The operating winding of the control relay I20 will then be energized to connect the motor 68 for energization across the control bus represented by the conductors H8 and II 6 by the closure of contact members I20a.

The circuit for energizing the operating winding' I20w of the control relay I20 may be traced from the energized conductor II8 through the switch I22, operating winding I20w, holding winding 64, break contact members I08a of the circuit breaker I08, and series connected contact members I282), I29?) and I30b to the energized conductor II6.

It will be recalled that the armature 6I is moved toward the core 63, Figure 1, and toward the holding winding 64 thereon when the motor 68 rotates the cam 70 to operate the toggle linkage by engagement with the roller 50. When the circuit breaker I0! is in the open position and the armature BI is at its furthest position from the winding 64, the impedance of this winding will be a minimum, and consequently suflicient current will flow through it to energize the operating winding I20w of the control relay I20 and close the contact members I20a. As the circuit breaker I01 reaches the closed position, the impedance of the holding winding 64 gradually increases because of the movement of the armature 6|. On engagement of the ar-' mature 6| with the core 63, the impedance of the holding winding 64 increases to a much higher value, and consequently there is a decrease in the current flowing through it and through the series connected operating winding I20w of the control relay I20. While current still continues to flow through the winding I20w, it is not suflicient to hold the contact members I200. closed and, as a result, the motor 68 is deenergized. The control relay I20 is so constructed that a diminution in energizing current of 50% of the initial value will cause the contact members I20a to be opened. The variation in impedance of the holding winding 64 is such as to cause a decrease in the current flow therethrough of approximately 90% of the initial value. While the necessary change in its impedance is of the order of l to 2 to effect the deenergization of the control relay I20 to the necessary extent, it actually changes in the ratio of 1 to 10. These figures are taken from a commercial embodiment of my invention, but it will be understood that other ratios may be emiployed without departing from the scope of my invention.

As the armature 6| approaches the winding 64, sufiicient force is exerted on the toggle linkage, as set forth hereinbefore, to effect the final closure of the circuit breaker I01. Therefore it is unnecessary to adjust with a high degree of accuracy the functioning of the control relay I20 in opening the energizing circuit for the motor 68. Furthermore, because of the arrange- :ment and construction of the linkage between the armature BI and the circuit breaker I01, only a very slight force need be exerted to hold it in the closed position. This force is provided by the greatly diminished current still flowing I through the holding winding 64, as will be readily understood.

Since the holding winding 64 is energized from the preferred power circuit 95, it inherently operates as an under-voltage device that will automatically release the circuit breaker I01 for movement to the open position on decrease in voltage on the preferred power circuit 95 to a predetermined value. 'For the particular circuit connection shown, a decrease in voltage between 1 the line conductor A and the neutral conductor N to a predetermined value will eirect a sufiicient deenergization of the holding winding 64 as to release the circuit breaker I01. While this control is not as sensitive as that which is provided 'by the voltage relays I28, I29 and I30, still use may be made of it if desired.

Assuming now that the voltage fails on one or more of the line conductors of the preferred power circuit 95, for example the line conductor B, the operating winding I29w of the voltage relay I29 will be deenergized, opening make contact members I29b and closing break contact members I29a. The previously traced energizing circuit for the holding winding 64 and "the operating winding I20w of the control relay I20 will then be opened at contact members I29b and the circuit breaker I01 will be released for movement to the open position. At the same time at contact members I29a a circuit will be completed for effecting the energization of the operating winding I2Iw of the control relay I2I to complete an energizing circuit at its make contact members I2Ia for connecting the motor 68 for energization across the control bus comprising the conductors H6 and H9.

This circuit may be traced from the energized conductor II6 through contact members I29a, auxiliary contact members I01a, which will be closed when the circuit breaker I01 is operated to the open position, holding Winding 64', operating winding I2Iw, and switch I23, to the energized conductor H9.

The circuit breaker I 08 will be closed by the motor 60 in a manner similar to that described for the closure of the circuit breaker I01. In like manner, the current flowing through the operating winding I2 Iw will be decreased as the circuit breaker I08 app-roaches the closed position, and the motor 68' will be deenergized. The circuit breaker I08 will be held in the closed position by the continued energization of the holding winding 64, even though the current flow therethrough is reduced to the minimum normal value.

It will now be obvious that as long as the circuit breaker I531 remains in the closed position, the previously traced circuit for eifecting the closure of the circuit breaker I 08 cannot be completedbecause the auxiliary contact members Ilila are open. In like manner, as long as the circuit breaker I08 remains in the closed position, its auxiliary contact member IOBa are open and the automatic operation of the circuit breaker I01? is prevented.

Assuming now that the line conductor B of the preferred power circuit 95 is again energized with the required voltage, the voltage relay I29 will be operated to open at contact members wile the energizing circuit for the holding winding G l, and the circuit breaker I08 will be released for movement .to the open position. At contact members I291) a circuit will be completed, as previously traced, for again effecting the operation of the circuit breaker I01 to connect the load circuit I06 for energization to the preferred power circuit 05.

If it is desired to effect the simultaneous operation of both of the circuit breakers I01 and I08, one or .the other of .the switches I 44 or I45 may be closed, depending upon which one of the circuit breakers is already closed. Assuming that the circuit breaker I01 is closed and it is desired to close the circuit breaker I08, the switch I45 is closed to connect the holding winding 64' and the operating Winding I2Iw of the control relay I 2! for energization directly across the control bus formed by the conductors H6 and I19. This circuit is obvious and will not be traced. The closure of the circuit breaker I will take place as described hereinbefore.

In like manner, if the circuit breaker I 08 is closed and it is desired .to close the circuit break- ,er I01, the switch I44 may be closed. A circuit is then completed for directly energizing the operating winding IZtw of the control relay I20 and the holding winding 64 from the conductors H8 and I I0, thereby shunting the auxiliary contact members I08a of the circuit breaker I08 and the make contact members of the voltage relays I28, I29 and I30.

While I have shown a system in Figure 9 of the drawings for operating the circuit breakers I01 and W8 as an automatic transfer system, it will be understood that these circuit breakers may be arranged for independent operation. That is, the auxiliary contact members I01a and Ida may be omitted together with the voltage relays I23, I29 and I30. The circuit breakers I01 and I03 may then be operated independently under the control of the switches I44 and I 35. In addition, as will be hereinafter set forth, suitable fault responsive relays may be provided for operating in conjunction with the circuits completed by the switches I M and M5 to automaticaliy open the circuit breakers It! and I 58 on the occurrence of a fault on the circuits in which they are connected.

It will now be apparent that when the holding winding 64, operating as a variable impedance device in conjunction with the armature SI, is used, no provision need be made for opening contact members when the circuit breaker controlled thereby reaches the closed position. It is unnecessary to take into consideration the effect of jars and vibrations on such contact members that are set up when the circuit breaker is closed. Moreover, it is unnecessary to provide complicated latch mechanisms that may be likewise affected by the shocks and jars, since the holding winding ti operates not only as a, cut-off mechanism but also as a holding mechanism, and at the same time it provides an added force for effecting the final closure of the circuit breaker associated therewith.

In Figure 10 of the drawings I have illustrated a modified circuit arrangement to provide the interlocking feature between the circuit breakers III? and I68 without requiring the use of the auxiliary switches IBM and Wild. The interlocking feature is obtained by connecting the holding windings EM and 64 in series circuit relation. The remaining circuit connections may be identical with those shown in Figure 9, eX-' cept for the provision of the control switches ms and I55.

In operation, assuming that the circuit breaker Ii'Ii has been closed, the impedance of the holding winding Iii will be so great that sufficient current would not be permitted to flow through the operating winding I2Iw of the control relay I2I to eiTect the energization of the motor 68'. In like manner, if the circuit breaker illil is in the closed position, the impedance of the holding winding (54' is so high that sufficient current would not be permitted to flow through the operating winding I25w of the control relay iii-El to effect the energization of the motor The automatic transfer of the cornmon load circuit I55 from the preferred power circuit 35 to the auxiliary power circuit IIBI on the occurrence of a fault on the preferred circuit will take Place as described hereinbefore, as well as the re-transfer to the preferred power circuit on removal of the fault therefrom.

It may be desirable to provide for mechanically latching a circuit breaker in the closed position that is operated to this position by the operating device described hereinbefore. For this purpose the circuit connections and construction illustrated in Figure 11 of the drawings may be employed. As there shown, a circuit breaker I55 is provided for connection in a circuit represented by the conductors X and Y. For the purposes of illustration only, a two pole circuit breaker is shown. The circuit breaker I55 may be operated to the closed position by the motor 65, which is arranged to rotate the cam I5 as described hereinbe'fore. The armature GI and winding 64 associated therewith may also be provided, but in this embodiment of my invention, its holding function is not required.

The operating mechanism of the circuit breaker I55 may be provided with a tooth I5I that is arranged to cooperate with a pawl I52 as biased by a compression spring I53. When the circuit breaker I50 is operated to the closed position by the motor 58, the pawl I52 is positioned underneath the tooth I51 and holds the circuit breaker in the closed position. Obviously the circuit breaker I50 may be released by manually moving the pawl I52 from engagement underneath the tooth I5I, or suitable electrical means may be provided for withdaawing it. The circuit breaker I50 is also provided with break contact members I50a, the function of which will presently be apparent.

The motor 68 may be controlled by a control relay, shown generally at I54, and which is provided With an operating winding I54w and make contact members I5 ia and I541). A manually operable control switch I55 is provided for connecting the control mechanism for energization to the secondary Winding I56 of a power transformer I51, the primary winding I58 of which may be connected for energization to the conductors X and Y.

In operation, the control switch I55 is closed, thereby completing an energizing circuit through the break contact members I5Ila for the operating winding I54w and the winding 64 from the secondary winding I56 of the transformer I51. At contact members I542) a circuit is completed for energizing the motor 68, and the cam I is rotated thereby to close the circuit breaker I55.

At contact members I550. the previously traced energizing circuit for the operating winding M5420 is opened. However, at contact members I540 a holding circuit is provided which maintains this energizing circuit intact. It will be obvious that it is unnecessary to provide for the opening of the contact members IEla at a precise instant after the circuit breaker I50 is operated toward the closed position. It is merely necessary to provide for opening these contact members at some time after the circuit breaker I58 is operated toward its closed position and before it reaches this closed position.

The impedance of the winding 54 is increased by movement of the armature BI toward it, as previously described, and, when the circuit breaker I50 is in the closed position, this impedance value is sufliciently high to reduce the current flowing through the operating winding I5 iw to such an extent that the contact members controlled thereby are opened. At contact members I542) the energizing circuit for the motor 58 is opened, and the cam returns to its original position. At contact members I550. the holding circuit for the operating winding I54w is opened, and this winding and the winding 64 are deenergized. It will now be apparent that no current flows through the windings I54w and 64 as long as the circuit breaker I50 remains closed. In this case the circuit breaker I5!) is held closed by the mechanical latch comprising the tooth I5I and the associated pawl I52.

In Figure 12 of the drawings I have illustrated, in a diagrammatic manner, the arrangement of the linkage shown in Figure 1 for operating the circuit breaker I50 to the closed position by the motor 68 and for holding it in this position by the continued energization of the winding 64. As previously described, the motor 68 is arranged to rotate the cam I0 in engagement with the roller 50 for operating the linkage in such manner as to close the circuit breaker I53. In this embodiment of the invention, the control relay I may be employed, having its operating winding I'Eflw connected in series circuit relation with the holding winding 64 on the core 53.

instead of the armature 6| being arranged to directly hold the pin 54 interconnecting the link 53 and the socket member 55, forming the third toggle joint, in a predetermined position, a latch member I60 is provided and is mechanically connected to the armature 6|, as illustrated. A tension spring I6I is provided for biasing the latching member I00 in a counterclockwise direction about its pivot point. The upper end of the latching member I60 is provided with an inclined surface I62 that is arranged to engage the pin 54.

On operation of the control switch I55 the control relay I20 is operated to energize the motor 66 and move the circuit breaker I toward its closed position through the linkage. The armature 6I is attracted toward the core 63, but it is prevented from immediately moving into engagement therewith because of the engagement of the inclined surface I62 of the latch member I60 with the pin 54. When the circuit breaker I5!) is operated to the closed position, the pin 54 has moved downwardly along the inclined surface I62 until the recessed underside I63 is reached, in which position the armature'fil is permitted to move toward the core 63, carrying with it the latching member I60 against the biasing force of the spring I6I. The impedance of the winding 64 correspondingly increases, and the current flowing through the operating winding I20w decreases to such an'extent that the contact members 120a are permitted to move to the open position. The motor 68 is deenergized,

but the circuit breaker I50 is held in the closed position by the latch member I60 as long as the holding winding 64 remains energized. As soon as the control switch I55 is operatedto the open position, the holding winding 64 is deenergized, and the spring I6I operates the latch I to release the pin 54. The circuit breaker I50, is then permitted to move to the open position.

In some commercial installations, it'is preferable to operate'the control mechanism for the circuit breakers from direct current rather than to utilize the alternating current from the circuits in which the circuit breakers 'are connected. For this purpose, the circuit connections shown in Figure 13 may be employed. As there shown, a suitablesource of direct current, such as a,

battery '60, is provided for energizing a control bus comprising conductors I6I and. I62 with direct current. The series motor 68 is arranged to operate the cam I0 to close the circuit'breaker I50.

It will be obvious thatthe circuit breaker I50 may be operated as a single unit, or it may be operated in conjunction with another circuit breaker to provide an automatic transfer system such as that shown in Figure 9 of the drawings.

As I have illustrated the embodiment of my invention in Figure 13 for use in such a system, the circuit breaker I50 is used in place of the circuit breaker I01 shown in Figure 9 of the drawings. The voltage relays I28, I29 and I30 could then be used, and the make contact members of these relays have been illustrated together with the auxiliary contact members I08a of the circuit breaker I08 to indicate how the system may be arranged for automatic transfer operation.

The motor 68 is arranged to be energized by contact members I63 that are closed by a suitable bridging contact member I 64 that is carried by a suitable insulating member I65 on an auxiliary armature I66 which is pivoted at I61 on a core I68. A Winding I69 is positioned around the core I68, as illustrated, and may be energized either by the control switch I55, or by the control circuit formed by the make contact members of the voltage relays and the auxiliary contact members of the associated transfer circuit breaker.

The circuit breaker I50 is held in the closed position by a main armature I10 that is pivoted at "I to the core I60 and connected by a link I12 to the pin 54.

In operation, on energization of the winding I69 the auxiliary armature I66 is attracted toward the core I68 against the biasing force of a spring I13, and contact members I63 are bridged by the bridging contact member I64. The motor 68 is then connected for energization between the conductors I6I and I62. While the armature I10 is attracted toward the core I68 fiuence of the spring I13 to open the contact members I 63 and deenergize the motor 68. As long as the winding I69 remains energized, the main armature I10 remains attracted thereby and the circuit breaker I50 remains in the closed position. On deenergization of the winding l69, the'main armature I10 is released and the circuit breaker I50 is permitted to operate to the open position, as will be readily understood.

As the main armature I10 approaches the core I68, the increased attractive force exerted thereon assists the motor 68 in operating the circuit breaker I50 to the final closed position. Thus, it is unnecessary to accurately adjust the particular instant in this cycle of operation when the contact members I63 are opened and the motor 68 is deenergized.

The arrangement and construction of my novel circuit interrupter forreclosing purposes are illustrated diagrammatically in Figure 14 of the drawings. As there shown, the circuit breaker I50 is arranged tobe closed by the motor 68 on rotation of the cam 10. The holding winding 64, associated with the armature 6|, is connected in series circuit relation with the operating winding I20w of the control relay I20 as described hereinbefore.

For the purpose of automatically opening the circuit breaker I50 on the occurrence of a fault.

on the circuit in which it is connected and for immediately reclosing it, an auxiliary control relay, shown generally at I15, is provided having I contact members I15a connected in series circuit which are'connected to eifect the energization of the operating Winding I15w from the secondary Winding I56 01 the transformer I51. The

relay I16 is provided with an operating winding I16w that is connected for energizationacross the terminals of a winding I11 of a current transformer that is associated with the line conductor Y.

The circuit breaker Ifit is initially closed by operation of a control switch I18, and it is held closed by the holding winding 64 in the manner described hereinbefore. On the occurrence of a predetermined overload, sufficient current flows through the winding Ilfiw of the overcurrent relay I'IB, and its contact members I'IBcL are closed to effect the energization of the operating winding II5w of the auxiliary control relay I15. The energizing circuitfor the holding winding 54 is opened at contact members I'I5a, and the circuit breaker I50 is permitted to operate toward the open position. As soon as the circuit is cleared, the winding I'Ifiw is no longer energized, and contact members I'Ifia are opened. Contact members I'I5a of the auxiliary control relay I75 are immediately reclosed to reestablish the control circuit through the holding winding 64 and the operating winding I2iiw of the control relay I20. The motor 68 is then energized to reolose the circuit breaker I50.

It will be obvious that the system may be so adjusted that it will be unnecessary for the circuit breaker I50 to be operated to the full open position. That is, the motor 68 may be energized sufficiently soon after the circuit breaker starts to move to the open position to cause the cam vmember I to engage the roller 50 before the latter is operated to the full open position. Thus, the circuit may be reclosed within a very short period of time, and it may even be closed within one cycle of GO-cycle current.

If the fault persists on the circuit, the foregoing reclosing cycle will be repeated. This pumping action may be prevented by any sui able means well known to thoseskilled in the art, and will not be described in detail herein. It will be obvious, however, that my novel circuit interrupter is inherently well adapted for functioning in connection with a reclosing circuit' breaker system.

In Figure 15 of the drawings, I have illustrated another embodiment of the reclosingsystem illustrated in Figure 14 and described hereinbefore. In this embodiment I have omitted the auXiliary'control relay H5 and the overcurrent relay I76 as such. Instead I have provided a relay,. showngenerally at I30, which operates in a manner similar to the variable impedance device formed by the armature 6| and the holding windingIM. This relay comprises a winding I8I which is connected for energization to the current transformer winding III that is associated with the line conductor Y. A second winding I82 is provided on the relay I80, and it is connected in series circuit relation with the holding winding 64. Armatures I83 and I84, connected by a link I05, are associated respectively with the windings I8I and I82.

The circuit breaker I50 is initially closed by operation of the control switch I'IB. At this time the armature I84 occupies a position with respect to the winding I82 such that the impedance of this winding is a minimum, and consequently the cycle for energizing and deenergizing the motor 68 takes place. The circuit breaker I50 is held in the closed position by the continued energization of the holding winding 64. On the occurrence of a fault, such as a short circuit, on the circuit in which the circuit breaker I50 is connected, sufficient current flows through the winding I8I to attract the armature I83 and to move the armature I84 to a position within the winding I82. In this position, the impedance of the winding I82 is materially increased and the circuit is so proportioned that this increase in impedance is suihcient to further decrease the current flowing through the holding winding 64 to such an extent that it is no longer capable of attracting the armature 6|. As a result, the circuit breaker I50 is permitted to operate to the open position.

As soon as the circuit breaker I50 has operated to this position, the winding I8I is deenergized and the armature I84 moves out of the winding I52. The impedance of this winding is correspondingly decreased, and the closing and holding cycle takes placefor operating and holding the circuit breaker I50 in the closed position. As long as the fault persists, the circuit breaker I50 will continue to be opened and closed. Suitable anti-pumping means may be provided for limiting the number of reclosures to one or to any desired number.

t will be obvious that the mechanical trip feature shown in Figure 11 of the drawings may be incorporated in either of the systems shown in Figures '14 and 15 of the drawings. With particular reference to Figures 11 and 14, it willbe obvious that the over-current relay II6' can be connected to control a tripping winding associated with the pawl' I52 to release the mechanical holding mechanism rather than to interrupt the current flowing through the holding winding 64, as in Figure 14.

Since it is obvious that certain further changes may be made in the above constructions and different embodiments of' the invention may be made without departing from the scope thereof,

-it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim as my invention:

1. In a circuit interrupter, in combination, relatively movable contact members for opening and closing an electric circuit, motor means for operating said contact members to the closed position, a control'relay anda winding therefor for controllingthe energization of said motor means, a variable impedance device disposed to operate together with said contact members and a winding therefor, and circuit means for connecting said windings in series circuit relation and to an alternating current source, the impedance of said device being relativelylow'when said contact members are in the open position and relatively high when they are in th closed position, whereby said control relay is'operated to deenergize said motor means.

2. In a circuit interrupter; in" combination,

relatively movable contact members for opening and closing an electric circuit, motor means'for operating said-contact members to the'closed position, a control relay and a winding therefor for controlling the. energization of saidmotor means, a variable impedance. device disposed to operate together with saidcontact members'and a winding therefor, circuit means for connecting said windingsin series circuit relation and to an alternating current source, and holding means for said contact members controlled by said variable impedance device, the impedance of said'device being relatively low when said contact members are in the open position and relatively high when they are in the closed position, whereby said control relay is operated to deenergize said motor means and saidholding meansis-acted up- 76 with said armature, a holding winding on said core, and circuit means connecting said windings ment of said armature toward said core on operation of *said contact members to the closed po-' sition, whereby said relay operates to deenergize said motor andsaid armature holding said linkage against movement, whereby said contact members are maintained in the closed position.

4. A circuit interrupter comprising, in combination, relatively movable contact members for opening and cl'osing an electric circuit, operating means for moving said contact members to the closed position, latching means for holding said contact members in the closed position, a control relay for effecting the energization of said oper-- ating means, a winding for said control relay, an armature movable with said contact members, a winding operatively disposed with said armature in such manner as to have a minimum of inductance when said contact members are open and a maximum of inductance when they are closed, auxiliary contact means disposed to be opened on movement of said contact members to the closed position, contact means on said control relay connected to shunt said auxiliary contact means on energization of the relay winding, a circuit means for connecting said auxiliary contact means, said relay winding and the variable inductance winding for energization to an alternating current source, whereby said control relay is operated to energize said operating means and, whereby said windings and operating means are deenergized when said contact members are operated to the closed position.

5. A circuit interrupter comprising, in combination, relatively movable contact members for opening and closing an electric circuit, an electric motor, linkage means interconnecting said contact members and said motor, latch means for engaging said linkage to hold said contact members in the closed position, said latch means being prevented from operatively engaging said linkage until said contact members are closed, means for biasing said latch means out of engagement with said linkage means, a control relay for effecting the energization of said motor, a winding for said relay, a core, a winding on said core, an armature movable relative to said core and connected to move with said latch means against the force of said biasing means, and circuit means for connecting said windings in series circuit relation and for energization to an alternating current source, whereby said motor is energized to operate said contact members to the closed position, said armature is attracted to said core to cause said latch means to operatively engage said linkage and said relay winding is deenergized to an extent suflicient to effect the deenergization of said motor.

ingmeans for moving said contact members to the closed position, a core, a winding for energizingsaid core, a main armature disposed to be attracted to said core on energization of said winding for holding said contact members closed, said main armature being movable toward said core only when said contact'members are moved to the closed position, an auxiliary armature disposedto be moved toward said core upon energization of said winding and to be released therefrom on-movement of said main armature to a position adjacent said core, contact means carried by said armature for effecting the energization of said operating means, and circuit means for connecting said winding for energization to a current source.

7. A circuit interrupter comprising, in combination, relatively movable contact members for opening and closing an electric circuit, an electric motor, linkage means interconnecting said contact members and said motor, a core, a winding for energizing said core, a main armature connected to and movable only with said linkage means, said armature being attracted toward said core on energization of said winding for holding said contact members closed, an auxiliary armature disposed to be moved toward said core immediately upon energization'oi said winding and to be released therefrom on shunting of said core by movement of said main armature, contact means carried by said auxiliary armature for completing an energizing circuit for said motor on energization of said winding and for opening said circuit when said auxiliary armature is released, and circuit means for connecting said winding for energization to a source of direct current.

8. In a circuit interrupter, in combination, relatively movable contact members for opening and closing an electric circuit, an electric motor including a rotatable member disposed to move said contact members to the closed position, an armature mechanically connected to said contact members and operable therewith, a winding cooperating with said armature, means for energizing said electric motor and said winding whereby the latter assists the former in operating said contact members to the closed position, means for deenergizing said motor on closure of said contact members, and means for maintaining said winding energized after said motor is deenergized to hold said contact members in the closed position.

9. Apparatus for moving a member from one position to an alternate position comprising, in combination, electric motor means for operating said member to said alternate position, a control relay and a winding therefor for controlling the energization of said motor means, a variable impedance device disposed to operate together with said member and a Winding therefor, and circuit means for connecting said windings in series circuit relation and to an alternating current source, the impedance of said device being relatively low when said member occupies said one position and relatively high when it occupies said alternate position, whereby said control relay is operated to deenergize said motor means.

10. In a circuit interrupter, in combination, relatively movable contact members for opening and closing an electric circuit, a torque motor,

Images