US2448615A

US2448615A - Switch

Info

Publication number: US2448615A
Authority: US
Inventors: Carl E Mesley
Original assignee: MATTHEWS W N CORP
Current assignee: MATTHEWS W N CORP; W N MATTHEWS Corp
Priority date: 1946-02-27
Filing date: 1946-02-27
Publication date: 1948-09-07
Anticipated expiration: 1965-09-07

Description

C. E. MOSLEY Sept. 7, 1948.

SWITCH Filed Feb. 27, 1946 9 Sheets-Sheet 1 Sept 7 1948- c. E'. MosLEY 2,448,615

Y l SWITCH y Filed Feb. 27, 1946 9 5116915-31891, 2

mum

Sept; 7, V1948. c` E. MosLEY 2,443,615

SWITCH A Filed Feb. 27, 1946 9 Sheets-Sheet 3 FIG.

Sept. 7, 1948. c. E. MosLEY 2,448,615

I swI'rcH Filed Feb. 2v, 194e l s sheets-sheet 4 FIGB.

Sept- 7 1948- c. E. MosLEY 2,448,615

sln'ca Filed Feb. 27, 1946 9 Sheets-Sheet 6 Sept. 7, 1948.

C. E. MOSLEY SITCH 9 Sheets-Sheet 8 Filed Feb. 27. 1946 SePt- 7, 1948- Y c. E. MosLEY 2,448,615

. SWITCH Filed Feb. 27, 1946 9 Sheets-Sheet 9 5? ffg |1624. 55 79 FIGZS.

TIME REQUIRED FOR J ALL OPERATIONS E 7` DELAY FIRST DELAY SECOND f7 FIRST CLOSING sEcoND .CLOSING 4 OPENING DELAY OPENING DEL Y SFl-TTOF THIRD OPENING INSTANTANED'JS.

LOCKED OPEN IF FAULT HAS NOT CLEARED. C'a-ve C? M J MTM M Patented Sept. 7, 1948 UNITED STATES PATENT OFFICE SWITCH Cari E. Mosley, Overland, Mo., assigner to W. N.

Matthews Corporation, St. Louis, Mo., a. corporation o! Hiaoolri Application February 27, 1946, Serial No. 650,675

14 Claims. (Cl. 20o-89) This invention relates to disconnecting switches, and more particularly to a reclosing repeater switch of that type.

Among the various objects ot the invention may be noted the provision of a reclosing switchior power lines and the like which w-ill open a. line with time-current relationships corresponding closely with the time-current relationships of fuses customarily used in sur-h lines; the provision of a switch of the class described which will repeatedly open and reclose a circuit a predetermined number of times, and then ultimately lock open; and the provision of an inexpensive multiopcning switch of this class which, without constant attention, is reliable under a wide range of operating conditions, being constructed without dashpots or similar usually unreliable time-delay means. Other objects will be in part obvious and in part pointed out hereinafter.

'I'he invention accordingly comprisesthe elements and combinations of elements, features of construction, and arrangements of parts which will be exemplified in the structures hereinafter described, and the scope of the application of which will be indicated in the iollowingclaims.

In the accompanying drawings, in which several of various possible embodiments of the invention are illustrated, y

Fig. 1 is a front elevation of my improved switch in normal closed position with its protective cover removed, parts being shown inl section;

Fig. 2 is a right-side elevation of Fig. 1;

Fig. 3 is a top plan view of Fig. l and showing e. surrounding cover;

Figs. 4 and 5 are horizontal sections taken respectively on lines 1 4 and 5-5 of Fig. l but showing said cover;

Fig. 6 is a view similar to Fig. l showing the parts in an intermediate stage oi a switch-opening action;

Fig. 'l is a fragmentary vertical section taken on line 'l-l of Fig. 6;

Fig. 8 is a view similar to Fig. l and Fig. 6, show-l ing the parts in a switch-open position;

Fig. 91s a fragmentary rear elevation of parts oi the device when in the Fig. 8, switch-open condition;

Fig. 10 is a modified form of over-center toggle switch;

Fig. 11 is a partial rear elevation of a timedelay mechanism shown in the Fig. 1 position;

Fig. 12 is a plan view oi Fig. 11;

Fig. 13 is a view similar to Fig. 11 but showing the mechanism shown in the Fig. 6 position;

Fig. 14 is a view similar to Figs. 11 and 13 but illustrating a switch-closing, delaying action;

Fig. 15 is an emerged vertical section taken on 2 line I 5-l 5 of Fig. 2, showing certain interlock parts in the positions of

FigsY

1 and 2;

Fig. 16 is an enlarged fragmentary vertical section taken on line |6-l6 of Fig. 2, the interlock parts .being shown in a rst moved position;I

Fig. 17 is a. view similar to Fig. 16, the interlock parts being shown in position to lock the switch open;

Fig. 18 is a horizontal section on line Il-l o! Figs. l and 15 and shows a recloser pin in normal position;

Fig. 19 is a view similar to Fig. 18 but shows the recloser pin holding the switch open;

Fig. 20 is a. horizontal section' taken on 'line 20-20 of Fig. 2;

Fig. 21 is a circuit diagram showing a normal condition;

Fig. 22 is a circuit diagram showing an initial circuit-opening phase;

Fig. 23 is a circuit diagram showing a nal action in said rst phase;

Fig. 24 is a circuit diagram showing a timedelayed reclosure action;

Fig. 25 is a circuit diagram showing a second reclosure action;

Fig. 26 is a perspective View oi a typical thermostatic element;

Fig. 27 is a developed view of the thermostatic element of Fig. 26; and

Fig. 28 is a chart oi the time-delay functions of the switch.

Similar reference characters indicate corresponding parts throughout the several views ci the drawings. d

There is a demand by power companies serving ruralareas and the like for an inexpensive, lecient recloslng switch to handle the numerous faults occurring on electric lines in such areas. These lines are diilicult to service and considerable time, trouble, and expense has been involved in their maintenance.

Onerequircment in a switch adapted for the above or similar conditions is repeating operations to restore service after temporary line faults for an indeiinite number of times without locking out. A second requirement is a repeating or multi-break operation, for example, two openings and two reciosures with a nal opening to clear permanent line faults. A third requirement is a mechanism which will provide a proper coordination of time and current upon opening, and a time-delay action upon reclosing, for each oi its cycles. A fourth requirement in such a switch is a ilnal locked-out, open-circuit condition which can easily be -reset to closed position by a line-` man. A fth requirement is reliability and safety in operation.

Attempts have been made to control the timedelay action of circuit breakers for use outdoors, by dashpots and the like, but these are unreliable and require constant attention.

Soienoids. which are generally reliable, have also been used but the time-current relationships of the solenoid actions in opening switches have not coordinated satisfactorily with the time-current curves of the customary fuses employed in these power circuits. The present invention provides the proper time-current coordination by using the reliable solenoids, but without the unreliable dashpots.

Spring-controlled escapement mechanisms have been used todelay the reclosing of switches of this class but it has been necessary to wind the mechanisms at intervals. The stated attention is undesirable and has lbeen eliminated in the present invention.

Referring now more particularly to Fig. 1, the switch comprises four corner-posts Il, 3 at the front and 5, 1 at the rear. Certain of these posts serve also as electrical conductors, as will appear. The posts are supported at the bottom on an insulating plate 9, and project upwardly to a similar top insulating plate II. Intermediate the top and bottom plates are two additional insulating guide plates I3 and I5 which, starting at the bottom, divide the switch as a whole into three levels A, B and C.

In the lower level A is located a primary solenoid i1 for opening the contacts of the switch and a secondary solenoid I9 for setting certain latches to be described later. In the intermediate zone B are located two thermostatically controlled over-centering toggle shunt switches referred to generally by the numerals 2l and 23. A reset pin 25 with associated interlocks is also located in this zone. In the upper zone C are the four contacts '21 of the main switches and ia delaying lever 29 with associated parts. Located at the left in Fig. 1, outside of the posts I and 5, is a spring-actuated escapement mechanism 3l.

A magnetic armature 33 of the solenoid I1 has an insulating extension 35 projecting up through the guide plate I5 to a rectangular supporting switch plate or crosshead 31. In the four corners of the plate 31 are bolted switch guide pins 39. Conducting bars lil electrically connect opposite pairs of sleeves 6I loosely telescoping the pins 39 (see Fig. 4).

When the switch is in its closed position (Fig. 1), the sleeves 6l' are in conductive rel-ation to yielding tubular

conducting contact sockets

43, 45, 41, 49, conduction being through lost-motion conducting sleeves 6| which frictionally telescope both the

sockets

43, 45, 41, 49 and the pins 39. The purpose of the sleeves 6I will appear. The

sockets

43, 45, 41, 49 are bolted to the insulating top plate Il. The

sockets

45 and 49 have conducting terminals 5I and, 53 associated there- I with.

Sockets

43 and 45 are connected to supporting posts I and 5, respectively, by conductors 55 and 51 (Fig. 3). The path of the incoming current from terminal 53 is as follows (see also Fig. 21): Terminal 53, socket 49, a sleeve 6|, bar 4|, another sleeve 6I on the same bar 4I, socket 41, link 51, post 5 and down to and through large solenoid I1 to post 1 via ,wire 4, then to the thermostatic element 22 of the thermostatic switch 23 (see connection |24), small solenoid I9 (via wire 24), out of solenoid i9 tothe thermostatic element v of switch 2| (via wire I8), back to post 3, (via connection |26) and then through bus bar 26 to post through the link nected to the respective conducting bars 4I. Each bar 4| actsas a crosshead between the respective members of a pair of sleeves 6| as well as acting as a conductor. When the main crosshead plate 31 is drawn down by the extension 35, the pins 39 will at ilrst slide out from the sleeves 6I which temporarily remain within the

sockets

43,45, 41, 49. This continues until catches 93, fastened on the sides of the plate 31, contact and move the connecting crosshead bars 4l with them (Fig. 6).. The upper ends 65 of the catches 63 are turned over to engage the bars 4| after predetermined downward movement of the catches 63. Continued movement of the plate 31 will finally withdraw the sleeves 6I from the sockets, thus opening the switch. The assemblies of sleeves 6I and connecting bars 4| will l ilnally drop by gravity relatively to the pins 39 to the switch-open position as shown in Fig. 8. This occurs after the sleeves 6| have been completely withdrawn from the tubes and provide increased gap openings without the necessity for increased travel of the member 35 in its solenoid. It will be observed that gravity is effective for the purpose only when the switch is upright or nearly so. Clearly, if the switch were to be used in other positions, the final opening `movement could be obtained by compression springs located on the respective catches 63 above the bars 4|.

When the sleevesV 6I are drawn down by action of the solenoid I1 (Fig. 8), the current will be broken at the four sockets 43. 45, 41, 49. The multi-break decreases the arc at any one point. Arc-suppressing insulator tubes 59, -attached to each of the sockets and extending therefrom, also help quickly to extinguish any arcs. The tubes may be made, for example, .of horn fiber.

The insulated extension 35 and the` switch plate 31 are held in a normal elevated position (Fig. l) by a compression spring 61. The spring surrounds the armature 33 and rests on the plate I3. The upper end of the spring bears against an adjustable collar 69 on the armature 33.

The downward movement of the armature 33 and associated parts is resisted by the delaying lever 29 pivotally mounted ina V-shaped bracket 1|. The inner end 15 of the lever is engaged for the purpose by a spring-pressed pawl 13 pivotally mounted on the insulating bar 33. This arrests the downward movement because the outer end 11 of the delay lever 29 is held against rocking movement by two

hooks

19 and 8| (see Fig. 6). Arrest occurs. after the lost motion (above described) has occurred but before the sleeves 6| are drawn into open-circuit positions.

The hook 8| is controlled either by a thermostatic operating element 29 of a single-throw switch 2| or by the small solenoid I9. 'I'he hook 19 is controlled by a thermostatic operating element 22 of a double-throw switch 23. 'I'he linkage for the hook 8| is as follows (see Figs. 1 and 20): A pivot pin 83 is supported in a U-shaped bracket mounted on the plate l5. This carries the two rotary hooks 19,'8I. Integral with the hook 8| is a horizontal lever 81 which extends from the hub of the hook to a point over a lift rod 89. The latter is connected to the armature 9| of the small solenoid I8. The lift r0d 5 Il extends upward from the solenoid through the zone B and is guided in the plate I5 directly beneath the lever 51. A cotter pin l5 through rod I directly aboveA plate I5 limits descent of rod 59. When the solenoid I9 is energized the amature and lift rod will be moved upward, raising the lever 81 and moving the hook around its pivot to an unlatched position frorn over the end 11 of the delaying lever (see Figs. 8 22 and 23). A stop bracket 931s positioned on the plate I to limit the upward movement of the lever 01 and hence limits rotary movement of the hook 5|. Gravity returns the armature 3| and lift rod I9 when solenoid I9 is deenergized. The stop pin 95 then comes to rest on the plate I3.

The second depending level 91 on the hook 5I reaches down into the zone l1 where it has a lostmotion connection (Figs. l and '7) with a horizontally disposed link 99 pivotally connected to the upper part of the leg |0| of the over-centering or toggle switch 2|. The leg |0| extends downward and has a spaced return portion |03. The leg |0|, at about its middle portion, is pivoted to a bracket |05 and the upper end of the .return portion |03 is also pivoted to this bracket coaxially with the rst pivot. Mounted between the'legs |0| and |03 is a lever |01 providing a movable seat for the upper end of a compression spring |09. The lever |01 is pivoted to the bracket |05 at a point above the axis of the pivots for the legs |0|, |03 (see Figs. 6 and 7), A link III pivotally connects the lever 01 with an insulated extension |00 from the free end of the U-shaped bimetallic thermostatic element 20. The other end of the thermostatic element 20 is ilxed on an insulating block ||5 supported from the corner posts 3 and 1.

The lower end of the compression spring |09 bears against a switch blade I I3 held between the legs |0| and |03 by rivets or the like. When the thermostatic element 20 is heated, the upper free end will move to the right (Figs. 1 and 6) ,'drawing to the right the connecting link il! and the upper end of the lever |01. The lower end of the pivoted lever |01 and the spring bearing upon it will be moved to the left, shifting the upper spring bearing from the right side to the left side of the pivot axis for legs 10|, |03. The compression of the spring |09 with a snap action shifts to the right, and into the switch contacts H1, the legs lili, |03 and switch blade |l3. This closes the shunt switch 2i. The upper end of the leg |01 will be moved to the left, which will rotate the hook 8| to an unlatched position clear Vof the end oi the delaying lever 29, Thus, either` the action of the solenoid 9 or heating ci the element moves the hook 8| from its latched to its unlatched position. During the lift of the lift rod 85, the light spring I I9 allows for the lost motion between lever 91 and link 99. Thus the solenoid |9 may cause retraction to the right of hook 8|, without closure ot switch 2|, spring ||9 being ineffective when compressed to operate the switch 2| against the toggle spring |09. When the lift rod 89 descends, the spring ||9 reexpands to take up the lost motion.

Whenever the over-centering toggle shunt switch 2| is closed (thermostatic element heated) the ihk |2| will be moved by the leg |0| to the left from its Fig. 15 position to its Fig. 16 position. This swings the upper end of the semaphore arm |23 to the left, moving the slot |25 to the right and into position to receive the interlock pin 25. The action oi' solenoid I9 and push rod 83 does not eiIect movement of the semaphore arm |23 because of the stated lost motion between

parts

91 and 39.

A link I3| is fastened at its one end to the lever |01 and at its other end to a horizontal arm |33 extending from a vertical pivoted post (Figs. 5 and 18). |31 extends from the pivoted post and bears against a. collar |39 on the interlock .pin 25. The interlock pin 25 is slidably supported in the bracket |21, its outer end being guided in an extension |4| of said bracket. It is within this extensionbracket that the collar |39 is conned. The inner end of the pin 25 extends through a keeper plate |28 also faste-ned to the bracket |21. A hole |43 in the keeper plate |28 is beveled on the side toward the -pin 25 for easy entrance.

This slide arm |54 is supported in a lower bearing attached to the bracket |21 (Fig. 18)

and extends upward into the level A where it has a bearing 3 in the plate l5 (Fig. 1S). A drag link |53 connects the top of the arm |53 with a rocker |55 pivoted in a bracket |54 fastened to the plate l. On the other side or its pivot the rocker carries a spring-pressed pawl |51 positioned to be contacted by a pin |59 (Fig. 16) secured in the side of theinsulated eixtension 35. This occurs when this extension moves down during initial opening movement of the

main contacts

43, 45, |11,V 49, as above described. Thus at the proper moment in the downward travel of the extension 35, provided the curved slot |25 has been moved so that the pin 25 may pass thereinto, the straight slot |49 will also be placed so that the pin may pass through it. However, lack of registry of either slot with the pin 25 locks out Ithe latter, even though it is cleared by arm |31. the insulated vextension is a spring-pressed pawl |53 (Fig. 19). When the extension 35 moves downward during each switch-opening cycle, the pawl |63 will pass by and 'below the plane of the interlock pin 25., In accordance with certain other events to be described later in the complete cycle of operations, if the interlock pin 25 has A second horizontal arm Mounted on a bracket IBI encircling 7 not progressed through the three interlock elements, thatis, the keeper |28, semaphore arm |23 and the vertical arm |49, the pin 25 will not be in the path of the pawl |53 and the latter may move down and up again .without interference. But should the interlock pin 25 have passed through the three stated elements, it will protrude out into the path of the pawl |53 and the pawl will pass it during downward movement but will be arrested in upward movement. This will'hold down the extension bar 35 andprevent the switch from reclosing at the sleeves ti and four

contact socket

43, 45, 41, 49. In other words, the switch will be locked out permanently until reset.

The above condition is a, nal one after a cycle of operations and requires 'manual reclosure by a lineman or other attendant. The reclosing is accomplished by applying a hook to a ring |55 provided on the outer end of the interlock pin 25. When this ring a'nd interlock pin 25 are pulled out, the inner operating end of the pin 25 is withdrawn from the three interlocked elements t28, |23, |49, and from above the pawl i019. The spring 61 about the armature 33 will then return the associated parts to the switch-closed position.

The linkage associated with the hook l is generally similar to the hook iti, but Ihook i9 is not operated by rod 83 from. the solenoid i3. Referring to Fig. 9 in particular, a. lever itl depends from the pivoted hook 13, .similar to the lever 01. The lower end of lever. lt'l has a lostmotion connection with a link B09, around which is a spring 202 similar to spring iii). Link its is pivoted to the upper end of a leg 20E of an overcentering toggle switch 23. The leg 263i extends downwardly and has a spaced return -portion 203. It is pivoted to a bracket 205. The upper end of the return portion 203 is also pivoted to this bracket 205 coaxially with the ilrst pivot for leg 20|. Mounted between the leg 20| and leg 203 is a lever 201 providing a. movableseat on its inner end for a compression spring 209. The lever 201 is pivoted to the bracket 205 at a point above the axis of the pivot for the legs 20L 203. At its upper end a link 2 il connects 201 lwith an insulated extenslon 200 from the free end of a second U-shaped bimetallic thermostatlc element 22.

The other end of this thermostatlc element is xed on an insulating block 265 supported from the corner posts 3 and 1. The lower end of the compression spring 209 bears against a switch blade 2|3 held between the legs 206 and 203 by rivets or the like. This switch 23 is a doublethrow switch. This type of switch is used to transfer the current flowing initially through the thermostatic element 22, solenoid i9 and switch .23 (see Fg. 2l illustrating a normal circuit), to a shunt circuitwherein the thermostatic element 22 and solenoid I9 are by-passed (see Fig. 23), after a nrst fault has occurred. After this, only the thermostatlc element 20 is inthe circuit, due to a reversal of the position of switch 23. In Fig. 9, the switch 23 is shown in its moved position (thermostat 22 heated).

When the thermostatic element 22 is heated,

snap action. This transfers blade 2|! from the l one switch contact clip 2li! to the other contact clip 2|1. Only the thermostatic element 22 controls hook 19 and consequently the reversing switch 23.

In Fig. 10 is shown a modified form of switch applicable to either switch 2| or 23. Instead of a metallic knife blade, the lower end of the compression spring |08 or 209 may bear on a metal element 2|2 riveted or otherwise held between the legs 20|, 205. Enclrcling clips 2|4, bent from the element 2 i2, tightly hold a glass capsule 215 con-` taining a small quantity oi mercury. Double leads 288 and 290 are fused into opposite ends of the capsule 2|5 so that various connections may be accomplished by using the four leads 233 or 290 when the capsule is tilted one way or the other. This mercury type switch has the advantage oi' certain non-arcing properties over other type switches and could be used equally well in the present invention.

The mechanical time-delay mechanism or escapement which is used for delaying the reclosing of the switch alter each opening (except the third and last opening) will now be described (Figs. 1, 3, 6 and 8). This mechanism is referred to generally by numeral 3i. It consists of a main shaft 22| on which is a relatively rotary actuator wheel 223 (see Figs. 1, 6, 11, 12, 13. 14). The wheel 223 carries on one side a springpressed pawl 225 engageable with a ratchet wheel 2211 attached to the shaft 22|. The shaft 22| is supported in front and rear frame pieces 229, the frame being in turn supported from the insulated plate i5. At one end the shaft 22i is encircled by a steel clockspring 23|, the inner coil of the spring being fastened to a hub 222 of. the wheel 223 while the outer yend is anchored to a post 240 on the frame 229. Movement of the actuator wheel in a clockwise manner (see arrow, Figs. 1-6) is unretarded by the pawl 225 which moves over the ratchet teeth but does wind the spring 23|. When the actuator wheel is allowed to move anti-clockwise. the spring will drive it and,

through action of pawl 225, drive the ratchet the latter being under control of a coil spring 244.

the upper free end will move to the left (Fig. 9),

Any suitable escapement mechanism may be used at this point. The action is such that a clockwise spring-winding movement of the actuator wheel 223 is followed by a delayed-action return in its counterclockwise movement.

Referring now to the opposite side of the wheel 223 (see Figs. 11, 12, 13 and 14), there is shown an adjustably mounted pin 245. The adjustment is in the form of an arcuate strip 241 upon which the p'in is mounted, the strip being held to the wheel 223 by a screw and slot combination 249. The position of the pin 245 may, within limits, be adjusted about the periphery of the wheel. The pin 245 bears against the outer free end of a pivoted trigger lever 25|. The pivot ls on the frame member 255 at 253. Member 255 is supported from the insulated plate I3, A stop pin 251 limits the lever movement (Fig. 11). Thus, further movement of the wheel 223 is limited by contact of the pin 24.5 with the lever. 'Ihis prevents the clock spring 23| from unwinding completely and allows means for tensioning the clock spring 23|.

spring to a degree which will insure instant ac tion of the escapment mechanism whenever the wheel 223 is allowed to return from its winding movement.

The upper end of the lever 25| will, under tension of a spring 259, follow the pinin the winding movement of the wheel 223 (counterclockwise in Figs. 11, 13, and 14). The lower endof the lever is formed as a hook 25|. When the pin 245 allows the upper end of the lever 25| to move to the right under influence of the spring 259, the hook 25| engages one end of-a pivoted latch 293 (see Figs. 13, 14). The latch 293 is held in position to receive the hook by a stop pin 255 and a spring 251. The latch 292 is pivoted at 259 to the frame member 255 and extends beyond in the form of a nose 21| to be contacted by a spring-pressed pawl 212. Pawl 213 is mounted on the insulated extension 35 oi the armature 33. A second spring-pressed pawl 215 is mounted on an outboard bracket 21| extending from the insulated extension 35. This is the escapement winding pawl and it is positioned so as to move the wheel 223 in a winding direction when the pawl is lowered, as when the switch opens at the contact sockets Il. 45. 41, 49. A pin 211 mounted on the wheel 223 is provided f'or this purpose. As will be seen from Figs. 11, 13, and 14, the pawl 215 contacts the pin 211 to turn the wheel 223. Then as turning oi the wheel continues, the pawl 213 will move past the nose 21| of the lever 263, Both of the pawls 213 and 215 are yielding in one direction of movement so that the parts may return to normal positions. This is likewise true of the pawls 13, |51, |53.

A housing 2, shown in section only in Figs. 3, 4 and 5, serves as weather protection. The only exposed parts are the top insulated plate with its line connection screws 5| and 53, and the reset ring 95 extending from the front side of the housing (see Fig. 4).

A complete cycle of operations is as follows:

Referring to Figs. 21-25, wherein S designates the entire switch at the top of member 35, current enters from the supply line through the closed switch S and ows to the solenoid i1 as above described. It then proceeds (Fig. 2l) to the thermostatic element 22, thence to the other solenoid i9 and to the thermostatic element 20.

It then proceeds through closed switch S to theA other side of the supply line.

Then an overload occurs, a, magnetic held is created in the large solenoid |1. This attracts the armature 33 and moves it downward, overcoming the compression of spring 61. The pins 29 start -to withdraw from the sleeves 6|, lost motion taking place-before switch S is opened. Details of the sleeves 6| and lost-motion mechanism in the switch are not shown in Figs. 21-25 (but see Figs. l, 6 and 8). The pin |59 Will contact the pawl |51 and raise the slide arm |5| so that the slot |49 can admit the pin 25. The pawl 213 will approach the nose 21|. Pawl 215 will contact pin 211 and through wheel 223 Wind Finally, the downward movement of the armature 33 is stopped by contact of pawl 13 with the end 15 of delaying lever 29. This occurs before switch S opens but after some lost motion has occurred therein.

The small solenoid I9 is affected by the current and its magnetic field will tend instantly to lift the armature 9| and through the rod 89 release the hook 8| from over the end 11 of the delaying lever 29 (see Fig. 22). This action of hook 89,

however, does not close the switch 2| because of -the lost-motion connection between levers 91 and 99 (see spring ||9, Figs. 1 and) Current will continue to ow through the ther- 'mostatic element 22, which expands and after some time moves the connecting link |99 (not shown in Figs. 21-25) to reverse the switch 23. and also to move .the hook 19 from above the end 11 of the delaying lever 29 (Fig. 23).

The result of the above phase of the first operation is that a time delay is created by the slowly expanding element 22, all preliminarily started switch-opening operations being halted until the hook 19 clears the end 11' of the delaying lever. This time delay is an important feature of the invention since it allows for better coordination between this switch and other fuses in the circuit. Referring to the chart Fig. 28, this time delay or duration is represented by the distance H charted on the total time line G. This duration H is dependent on two factors, (1) the size of the bimetallic element 22 and (2) the magnitude of the fault current. Obviously, no control can be exercised over the magnitude of the fault current. But the thermostatic element 22 is so designed as to have its heating and current-carrying relatio" ship in keeping with that of the fuses in the circuit in which the present device is used. Fuses or different types havev different periods of time in which they will heat, and melt to a rupturev point. The element 22 in the present invention is designed to expand to an operative degree just before any rupture of the fuses in the circuit. This is what is meant by the coordination already referred to.

Continuing with the operation: When the hook 19 releases the end 11 of the delaying lever, the magnetic field in solenoid i1 continues to pull the armature 33 downward. The now free delaying lever 29 is pivoted about its center by action of the pawl 13. The turned-over upper ends 65 of the catch E3 engage the bars 4E andpull the tubes 6| clear from the

sockets

43, 45, I1, 49, which opens the switch S, and hence the circuit.

The pin E59 passes from the pawl |51 and slide arm |5| drops, taking its opening |25 out of the plane of the pin 25. The pawl 213 will'pass under the cam nose 21|. Pawl 215 will advance the wheel 223, freeing lever 25i, allowing spring 259 to pull the lever 25|, so that its hook 26| engages and holds the end of lever 263 (see Figs. 14 and 23) The additional advance of the wheel 223 will further wind the spring 23| and finally the wheel 223 will have turned sufiiciently to allow pawl 215 to pass the circularly moving pin 211. The downward movement of the armature 33 will finally be arrested by the compression of the spring 51.

As the element 22 releases the hook 19, it also reverses the switch 23, the arm of .the switch swinging with e. snap action from the Contact clip 2|8 to Contact clip 2|1 (see Figs. 21-23).

The flow of line current is now broken; The armature of solenoid |1 cannot immediately return upward by action of spring 61 because the pawl 213 is held beneath the cam nose 21|. The latch 263 associated with this cam nose is held against movement by the trigger hook 26| (Figs. 8 and l2) The armature 9| and lift rod 89 descend by gravity, allowing the hook 8| to return to a holding position above the end 11 of the delaying 1ever'. This action is made positive by the spring ||9 about the connecting link 99.

There now occurs a. predetermined time delay imposed by the running down of the escapement mechanism 3| (Fig. 14). This time delay allows for the fault 'to clear itself from the line if this the thermostatic element 22 which control 4the cam nose 21| and pass it. The pawl 215 will,

during upward movement, pass the pin 2li. The pin iiiwill pass the yielding pawl |517. The pawl |73 springs past the delaying lever nose 'i5 and the pins 39 will drive the tubes 6| back into the sockets t3, if. lll, lle thereby reclosing the switch. for a second cycle. All parts have now returned to their starting positions with the exception of the switch 23 and hook 19. Some time is necessarily required for this thermostatic element 22 to cool. This time is preferably of a greater duration than the reclosing time relay introduced by the escapement mechanism. This results in holding the 'hook it clear ofI the delaying lever 'i1 and holdbut now the switch 23 is in reversed position (see Fig. 24) and the cooling thermostat 22 and solenoid i9 are shunted out'of the circuit. The current now tnavels from bar |26 and contact 2|1 through the switch arm 20| and blade 2|3 via cross connection |28 to the stationary end 'of thermostatic element 20, then out of the element 20 to post 3 via connection |28 and thence as described before, leaving at the terminal 'di The armature 33 will again be pulled down by energization of the large solenoid i1 and the same mechanical functions of the various parts attached toit will again take place, until the armature is stopped by the delaying lever 29. It is to y other feature of the invention.

When the thermostat 20has expanded suinciently to release hook 8| from the delaying lever 23, the armature will continue downward as be fore and the switch S will again open. The lever attached to insulated extension 3 of the thermostatic element 20 closes the switch 2| and,

i cycle.

through levers |33 and |31 connected to the lever I IH, releases the pressure on the collar |39 on interlock pin 25. After the pin |59l has temporar ily raised and lowered the slide arm ISI, the slot- IS will not be in the plane of the pin 25 and no interlock will take place at this time (Fig. 16) But the `pin 25 may enter the slot |25 in the semaphore arm |23 which has been moved into receptive position through action of the connecting, link |2| attached to the switch arm IUI. The

pin 25 has now entered the semaphore arm |23 and is ready to enter and interlock with. slot |43 on the next and final operation (Figs. 17 and 19) The pawl 2id will again spring past and under the cam nose 2li and be caught thereunder. The wheel 223 has been turned as before to wind the spring and release the lever 26| which holds the cam nose in position while the escapement allows the wheel 223 slowly to return. It may be noted here that the spring actuating the escapement is wound by the downward movement of the armature t3. No additional attention such as winding or adjusting is needed, once the circuit breaker is properly placed in the circuit.

The switch is now open on its second cycle (Fig. 25) and willbe held open while the escapement is'delayiiig the return of the wheel 225. This delay is represented by the distance E in the chart (Fig. 28). The time represented depends on the adjustment of the escapement mechanism iii. It has been determined that about 3 seconds is the proper time for this delay in reclosing. Thus distances.J and E both represent 3 seconds.

Thus a second opportunity is presented for the fault or short circuit to clear itself. The main switch recloses as before and the parts will again resume their normal positions with the exception that now the second hook si as well as the hook le has not returned immediately. The thermostatic element 22 still has not cooled sillciently and will hold the hook le fromthe delaying lever end 1l and also retain the switch arm 2 i3 in the contact 2W. It is to be remembered that this shunts out the element 22 and solenoid i9.

The thermostatic element 20 also requires a like time to cool. While it is contracting it lwill hold back the hook 8| from the delaying lever 29. The switch 2i will be closed and thelinkage from the semaphore arm |23 remains in position to release the interlock pin 2.5 and allow it to extend through theu slot of the semaphore arm ready to enter the slot inthe vertical slide arm IM when that arm again passes theY plane of the pin 25. The now closed switch 2| is for the purpose of shunting out the element 20. It will vbe seen now that if the excessive current still persists upon reclosing of switch S it will be shunted from the coil I9 and element 22 (by switch 23) and from the element 20 (see Fig. 25).

The current now ows throughv the reclosed main switch as before, the large solenoid I1, and through post 1 and link |24 to contact 2I1, switch arm 2|3, link |30 to switch arm ||3 and contact I1 which has a connection through conducting bar ||2 to the link |23 to post 3. Here it leaves through link bar 26 and out of the switch as before.

Now only the large solenoid I1 is energized and it will pull the armature 33 downward as before, but the entire opening action is instantaneous. The pawl 13 will pass by the free delaying lever 29. The spring 23| will be wound as before but the escapement action 3| has no function in this The pin 259 will again raise the vertical arm :5| and interlock'pin 25 will now pass into the slot (see Figs. 17, 19). The pawlA |63 will spring past the protruding interlock pin 25 and be held under it, the main switch S being heid open permanently. 'Ihe escapement runs down to its normal position and releases the hook 28| from holding position so that pawl 213 may re turn past the cam nose 21| when the circuit breaker is :finally reset. 'I'his third instantaneous opening of the switch is represented by the short distance F in the chart (Fig. 28).

As is clear. the locking-open action is accom- 13 plishe'd by the interlock pin 25 being so placed in the path of the pawl |02 that the armature 22 may not return automatically to reclose the main switch. These parts willremain in this cnndition until attended to. The element 22 will iinally cool and return the hook l to position above the delaying lever 29. This action also returns the single-pole double-throw switch arm 2 I3 from contact 2|0 to contact 2|1. This again places the small solenoid Il and element 22 in the circuit.

The element 20 also cools and tends to withdraw switch arm H3 from the contact H1 to its open position but is prevented from doing so by the linkage connected to the interlock pin. It merely stands in a sprung-open position ready to act.

The pressure of the armature spring 81 to return the armature upwardly creates enough friction on the interlock in 25 (see Fi'g. 19) protruding through the three elements of the interlock, that is, the bracket |21, the semaphore arm |23 and vertical arm ISI, to hold the pin in this position against the inherent spring action of the element 20.

After the lineman has cleared the fault he is ready to reclose the switch ior another series of operations. For this purpose the pin '25, by means of ring |65, is withdrawn (see Figs. 4 and 18). This allows the armature to return the main switch S to a closed position. It also allows the now cool thermostatic element 20 to spring back, returning the single-pole single-throw switch 2| to its open position. This reconnects the element 20 into the circuit. All the parts are now in the original normal position and the circuit breaker is ready for a subsequent series of operations.

The particular form of each

bimetallic electrothermostatic element

20 and 22 is of importance and is shown in Figs. 26 and 27. These elements are similar in form. The general formils U- shaped, as indicated in Fig. 26, with the anchor end at 30! and the movable end at 302. In Fig. 27 the-U-shape has been laid out into a flat development for purposes of description, but it is to he understood that the actual form is as shown in Fig. 26. Each U-shape is composed of two

outside strips

303 and 305 which have terminals at 301 and 30S, respectively. At their opposite ends 3M and 308, these

strips

303 and 305 are conductively connected to inside strips 3H and 3|3. Near the terminal ends these strips 3H and 3|3 are connected as shown at 3|5. This construction provides a looped conductive structure which, when bent into the U-shape of Fig. 2S, provides a cross section for ow of current which is substantially less than if the'U-shape were made of a solid bimetallic ribbon. Thus the'desired electrical heating may be obtained with less current'than would be required for the same heating if a solid, wide ribbon were used. The heating characteristics of the thermostatic element are thus adapted to the current for which the switch is to be designed. Smaller or larger cross sections for current flow could be established by employing more or fewer of the

loops

303', 305, 3H and 3|3 for a given width of thermostat.

The

multiple loops

303, 305, 3H and 3|3, when bent into the U-shape of Fig. 26, provide for increased actuating force of the thermostat for a given heating because, from a mechanical viewpoint, several loops are acting in parallel, although frorn an electrical viewpoint the respective loops are acting in series. Thus by employing in a U-shape several loops which are connected in series electrically but arranged in parallel mechanically, a given thermostat may be designed for any reasonable actuating force with any reasonable current-heating characteristic.

It will also be understood that more thermostatic elements, such as 20, 22: over-center toggle switches, such as 23; and solenoids,such as I9 (see Figs. 2l, 22, 23, 24 and 25), in combination can be incorporated in the design to change the number and sequences of operations shown in Fig. 28. l i' It will be understood that each loop 203, 300,

3| 3|3' is composed of the usual bimetal used for such thermostatic elements. It should be understood that the cross sections of the

loops

203, 305, 3| l, 3|3 are predetermined so that a normal current flowing through the circuit protected by the apparatus will not move the free ends 302 oi' the thermostatic elementl enough to cause them substantially to move any of the apparatus connected with the thermostatic elements. Only overload current is capable of this.

It should be understood that although the

terminals

301, 309 are connected in a circuit, as above described, the support I l5 therefor is insulating (Fig. 6), as is the support for the point SI5. The holes for the supporting screws are shown at 3|0 in Figs. 26 and 27. Also, the mem- 'Der such as 200. connected at the movable end. is also insulated. The holes at this end for the supporting screws are shown at 3i2in Fig. 27.

In view of the above, it will be seen that the several objects of theinvention are achieved and other advantageous results attained.

As many changes could be made in the above v constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. In overload disconnecting apparatus, a line' switch normally biased toward lclosing position, a connection in the line and controlled by said switch, said connection including a rst main solenoid. a rst electro-thermostatic element, a second solenoid and a second thermostatic elementa first shunt switch operated by the rst thermostatic element and a second shunt switch .operated by the second thermostatic element, said irst shunt switch normally shunting the second thermostatic element and being adapted in response to overload heating of the first thermostatic element to connect said second thermostatic element and to shunt the first thermostatic element and the second solenoid, said second shunt switch effecting a normally open shunt around said second thermostatic element and being operative by said second thermostatlc element to close said last-named shunt, overload current from the line in said connection being adapted to operate the main solenoid to apply opening force to the line switch, and said thermostatic elements being adapted in response to said overload current more slowly to operate their respective switches, a detent restraining immediate opening of the'line switch in response to said force of the main solenoid, and catches ternporarily restraining the detent, one of which catches is operative with time delay from the first thermostatic element and the other of which is operative instantly from said second solenoid and with time delay from said second thermostatic element.

ams

2. In overload disconnecting apparatus, a line A switch normally biased toward closing position, a connection in the line and controlled by said switch, said connection including a first main shunt switch effecting a normally open shunt around said second thermostatic element and being operative by said second thermostatic element to close said last-namedshunt, overload current from the line in said connection being adapted to operate the main solenoid to apply opening force to the line switch, and said thermostatic elements being adapted in response to said overload current more slowly to operate their respective switches, a detent restraining immediate opening of the line switch in response to said force of the main solenoid, catches temporarily restraining the detent, one of which catches is operative with time delay from the first thermostatic element and the other of which is operative instantly from said second solenoid and with time delay from said second thermostatic element, a first overload current causing said second solenoid promptly to move its connected catch from the detent and thev first thermostatic element thereafter causing its connected latch more slowly to move from said detent, whereby the main solenoid may open the line switch, a timedelay mechanism, a catch controlled by said time-delay mechanism, and a latch associated with said line switch and held by said time-delay catch when the line switch is open until said time-delay mechanism releases said catch to allow time-delayed reclosing of the line switch under its reclosing bias. 3. In overload disconnecting apparatus, a line switch normally biased toward closing position, a connection in the line and controlled by said switch, said connection including a first main solenoid, a first time-delay electro-thermdstatic element, a second solenoid, and a. second timedelay-electro-thermostatic element connected in series, a first shunt switch operated by the first thermostatc element and a second shunt switch operated -by the second thermostatic element, said first shunt switch normally shunting the secondl thermostatic element and being adapted in response to overload heating of the first thermostatic element to connect said second thermostatic element and to shunt the first thermostatic element and the second solenoid, said second shunt switch effectinga. normally open shunt around said second thermostatic element and being operative by said second thermostatic element to close said last-named shunt, overload current from the line in said connection Ibeing adapted to operate the main solenoid to apply opening force to the line switch, and said thermostatic elements being adapted in response to said overload current more slowly to operate their catches is operative with time delay from the firs thermostatic element and the other of which is operative instantly from said second solenoid and with time delay from said second thermostatic element, a first overload current causing said second solenoid promptly to move its connected catch from the detent and the first thermostatic element thereafter causing its connected latch more slowly to move from said detent, whereby the main solenoid may omn the line switch, a time-delay mechanism, a catch controlled by said time-delay mechanism, a latch associated with said line switch and held by said time-delay catch when the line switch is open until said timedelay mechanism releases said catch to'allow time-delayed reclosing of the iine'switch under its reclosing bias, and means whereby the timedelay mechanism is energized for time-delay action by the opening action of the line switch each time that said line switch opens.

t. In overload disconnecting apparatus, a line switch normally biased toward closing position, a connection in the line and controlled by said switch, said connection including a first main solenoid, a first time-delay electro-thermostatic element, a second solenoid and a second timedelay electro-thermostatic element connected in series, a first shunt switch operated by the first thermostatic element and a second shuntswltch operated by the second thermostatic element, said' iirst shunt switch normally shunting the second thcrmostatic element and being adapted in response to overload heating of the first thermostatic element to open said shunt and to shunt the first thermostatic element and the second solenoid, said second switch determining a normally open shunt around said second thermostatic element and being operative by said second thermostatic element to close said last-named shunt, overload current from the circuit and in ,said connection being adapted to operate the main solenoid to apply opening force to the line switch, and said thermostatic elements being adapted in response to said overload current more slowly to operate their respective switches, a detent restraining immediate opening of the line switch in response to the opening force oi' the main solenoid action, and catches temporarily restraining the detent, one o1' which catches is operative with time delay from the nrst thermostaticv element and the other of which is instantly operative from said second solenoid and with time delay from said second thermostatic element, a first overload current causing said second solenoid ,promptly to move its connected latch from the detent and the first thermostatic element thereafter causing its connected latch more slowly to move from said detent, whereby the main solenoid may open the line switch, time-delay mechanism, a catch controlled by said time-delay mechanism, a latch associated with said line switch and held by said time-delay catch Vwhen the line switch is openn until said time-delay mechanism releases said' time-delay catch to effect a first time-delay reclosing of the line switch under its reclosing bias,

said second thermostatic element upon a con-l tinuing overload current being adapted to withdraw its catch with time delay to allow said main solenoid to reopen the switch for a, second time-delayed reclosure. v

5. In overload disconnecting apparatus, a line switch normally biased toward closing position, a connection in the line and controlled by said switch, said connection including aI first main solenoid, a first time-delay eleotro-thermostatic element, a second solenoid and a second timedelay electro-thermostatic element connected in series, a first shunt switch operated by the iirst thermostatic element and a second shunt switch operated by the second thermostatic element, said first shunt switch normally shunting the second thermostatic-element and being adapted in response to overload heating of the first therl mostatic element to open said shunt and to shunt the rst thermostatic element and the second solenoid, said second switch determining a normally open shunt around said second thermostatic element and being operative by said second thermostatic element to close said lastnamed shunt, overload current from the circuit and in said connection being adapted to operate the main solenoid to apply opening force to the line switch, and said thermostatic elements being adapted in response to said overload current more slowly to operate their respective switches, a detent restraining immediate opening of the line switch in response to the opening force of the main solenoid action, and catches temporarily restraining the detent, one of which catches is operative with time delay trom the ilrs't thermostatio element and the other of which is instantly operative from said second solenoid and with time delay from said second thermostatic element, a first overload current causing said second solenoid promptly to move its connected latch from the detent and the rst thermostatic element thereafter causing its connected latch more slowly to move from said detent, whereby the main solenoid may open the line switch against its bias, a time-delay mechanism, a catch controlled by said time-delay mechanism, a latch associated with said line switch and held by said time-delay catch when the line switch is open until said time-delay mechanism releases said time-delay catch to eiect a first time-delay reclosing of the line switch under its reclosing bias, said second thermostatic element upon a continuing overolad current being adapted to withdraw its latch with time delay to allow said main solenoid to reopen the switch for a second time-delay reclosure, a lock-out latch biased toward locked-out position, a connection with said second thermostatic element for holding said second thermostatic element, a lock-out catch movable with the line switch and engageable with said lock-out latch, first and second means responsive to overload action of said second thermostatic element and opening action of the line switch permitting said lock-out latch to move into position to be engaged by said lock-out catch of the line switch nally to hold the latter open permanently.

6. In overload disconnecting apparatus, a line switch normally biased toward closing position, a connection in the line and Controlled by said switch, said connection including a rst main solenoid, a first time-delay electro-thermostatic element, a second solenoid and a second time-'- delay electro-thermostatic clement connected in series, a rst shunt switch operated by the first thermostatic element and a second shunt switch operated by the second thermostatic element, said rst shunt switch normally shunting the second thermostatic element and being adapted in response to overload heating of the ilrst thermostatic element to open said shunt and to shunt the first thermostatie element and the second solenoid, said second switch determining a normally open shunt around said second thermostatic element and being operative by said second thermstraining immediate opening of the line switch in response to the opening force of the main solenoid action,.and catches tempor-arily restraining the detent, one of which catches is operative with time delay from the first thermosratic element and the other of which is instantly operative from said second solenoid and with time delay from said second thermostatic element, a first overload current causing said second solenoid promptly to move its connected latch from the detent and the ilrst thermostatlc element thereafter causing its connected latch more slowly to move from said detent, whereby the main solenoid may open the line switch against its bias, a time-delay mechanism, a catch controlled by said time-delay mechanlsxn, a latch associated with said line switch and held by said time-delay catch when the line switch is open until said time-delay mechanism releases said time-delay catch to effect a first time-delay reclosing of the line switch under its reclosing bias, said second thermostatc element upon a continuing overload current being adapted to withdraw its latch with time delay to allow said mainlsolenoid to reopen the switch for a second time-delay reclosure, a lock-out latch biased toward locked-out position, a connection with said second thermostatic element for holding said lock-out latch against its bias in normal position of said second thermostatic element, a lock-out catch movable with the line switch and engageable with said lock-out latch, first and second means responsive to overload action of said second thermostatic element and opening action of the line switch permitting said lock-out latch to move into position to be engaged by said lockout catch of the line switch finally to hold the latter open permanently, while the time-delay mechanism runs down, mear s for at will manually withdrawing said lock-out latch to permit instantaneous, reclosing of the line switch in the absence of time delay from the time-delay mechanism, and means whereby the time-delay mechanism is rewound upon each opening action of the line switch.

rI. In apparatus of the class described, a line switch normally biased toward closed position, a quick-action solenoid for opening said switch, a time-delay mechanism adapted to be wound by the switch upon opening, a release latch controlled to be released by said time-delay mechanism, and a catch movable with the switch and engageable with said latch to hold the switch open until release of said latch by said time-delay mechanism. 4

8. In apparatus of the class described, a line switch normally biased toward closed position, a quick-action solenoid responsive to overload line current for opening said switch, a detent limiting movement of the switch before it opens, an elec'- tro-thermostat responsive to overload line current, a catch for the detent operative by said thermostatic element in response to overload current to release said detent to allow complete opening movement of the switch in response `to overload current in said solenoid, a time-delay mechanismV adapted to be wound by the switch upon opening, a releasing latch for said switch conaacaais trolled `to be released by said time-delay mechanism, sind a catch movable with the switch and engageable with said latch to hold the switch open until release of said latch by said time-delay mechanism. i y

9. In apparatus ofthe class described, a line switch normally biased toward closed position, a quick-action solenoid responsive to 'overload line current for opening said switch, a detent limiting movement of the switch before it opens, an electro-thermostat responsive to overload line current, a catch for the detent operative by said thermostatic element in response to overload current to move from said detent to allow complete opening movement oi the switch in response to overload current in said solenoid, a second electrothermostat, a second catch movable by overload current in the second thermostat to move from each said detent, and switchv means controlled by the thermostats determining current now first to one thermostat exclusively and then to the other.

10. In apparatus of the class described, a line switch normally biased toward closed position, a quick-action solenoid responsive to overload line current for opening said switch, a detent limiting movement of the switch before it opens, an electro-thermostat responsive to overload line current, a catch for the detent operative by said thermostatic element in response to overload current to move from said detent to allow-complete' opening movement of the switch in response to overload current in said solenoid, a second electro-thermostat, a second catch movable by overload current in the second thermostat to move from said detent, and switch means controlled by the thermostats determining current flow first to one thermostat exclusively and then to the other, a time-delay mechanism adapted to be wound by theswitch upon opening, a latch for said line switch controlled to be released by said time-delay mechanism, a catch movable with the switch and engageable -with said latch to hold the switch open until release of said latch by said time-delay mechanism.

11. In apparatus of the class described, a line switchnormally biased toward closed position, a quick-action solenoid responsive to overload line current for opening said switch, a detent limiting movement of the switch before it opens, a ilrst electro-thermostat responsive to overload current in the line served by the switch, a catch for the detent operative by said rst thermostat in responsegto overload current in the latter to re' tent for holding it to prevent initial switch openmove said second catch independently of the second thermostat when the ilrst thermostat is operative, and switch means controlled by the thermostats determining current ow iirst exclusively -to the ilrst thermostat and the second solenoid current for initially clearing one catch from the i detent. a iirst thermostatic means operative slowly by heating in response to overload current to remove the other catch from the detent to allow a ilrst opening action of the switch, time-delayA ing, solenoid means operative in response to overload current for initially clearing one catch from .to remove the other catch from the detent to allow a first opening action of the switch, timedelay means permitting reclosing of said switch after an interval, and second thermostatic means operative in connection with said rst catch to remove it from said detent independently of operation of said catch by said second solenoid means to allow a second reopening and reclosing of the switch. and catch means operative upon any third movement of the switch for permanently holding the switch open.

14. In apparatus of the class described a line switch normally biased toward closed position, a solenoid subject to line current adapted to apply force to the switch to open it, a detent normally preventing opening of the switch, a catch normally holding the detent to prevent switch opening, a thermostatic element associated with the catch and responsive to overload line current to move the catch from the detent to permit opening of the switch by the solenoid in response to overload line current in the latter, a lock-out latch biased toward a lock-out position, means connecting said thermostatic element andthe latch which in the normal position of the thermostatic element holds said lock-out latch against its bias and in a heated position of said element removes the hold, a movable stop means'connected with the thermostatic element and adapted upon heating of the latter to be drawn into position to allow biased movement of the lock-out latch, a second movable stop means normally preventing movement of the lock-out latch to lock-out position, and means cooperating between the switch and said last-named stop means to move .it to clear the lock-out latch for biased movement to the lock-out position as the switch moves to its open position. CARL E. MOSLEY.

y REFERENoEsCITEn The following references are of record in the file of this patent:

UNITED STATES PATENTS Date Number Name 1,952,372 Grace Mar. 27. 1934 1,967,890 i Kuhn July 24, 1934 2,088,420 Koch July 27, 1937 2,090,169 Wilms et al. Aug. 17, 1937 2,096,706 Shoemaker Oct. 19,1937 2,213,080 Bork Aug. 27, 1940