US3806848A

US3806848A - Snap action breaker with housing

Info

Publication number: US3806848A
Application number: US00303954A
Authority: US
Inventors: G Harper; J Shand
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-11-06
Filing date: 1972-11-06
Publication date: 1974-04-23
Anticipated expiration: 1991-04-23
Also published as: GB1447780A; FR2205734A1; FR2205734B1; JPS4978182A; JPS54501B2

Abstract

Disclosed is a circuit breaker incorporating a snap action switch. The breaker incorporates a simplified toggle mechanism and one or more of the breakers may be combined with one or more similarly constructed power switches to form a novel multifunction modular package.

Description

[ Apr. 23, 1974 United States Patent 11 1 Harper et a1.

[ SNAP ACTION BREAKER WITH HOUSING 3 395,372 7/1968 Opad 3,488,609 1 1970 St k [76] Inventors: George S. Harper, 423 Lmden Ave, 3,164,700 151965 Bsdeesschatzw Cambndge, 21613; John 3,305,806 2/1967 Richard Shand, RFD No. 4, Easton,

Primary Examiner1-1aro1d Broome [22] Filed: Nov. 6, 1972 Attorney, Agent, or Firm-LeBlanc & Shur [21] App]. No.: 303,954

ABSTRACT [5 1 U S Cl 335/188 335/191 Disclosed is a circuit breaker incorporating a snap action switch. The breaker incorporates a simplified toggle mechanism and one or more of the breakers may be combined with one or more similarly constructed power switches to form a novel multi-function modular package.

References Cited UNITED STATES PATENTS 9 Claims,

Kussy et 17 Drawing Figures FATENTEUAPR23 m4 "55.808848 SHEET 1 [IF 7 FIG. I

EATENTEDAFR 23 1974 SHEET 5 OF 7 RATENTEDAPR 23 law 3 806; 848

SHEET 6 0F 7 FIG. l2

FIG. l3

2ATENTEDAPR2319Y4 $806548 SHEET 7 [1F 7 FIG. l6

the

SNAP ACTION BREAKER WITH HOUSING This invention relates to a circuit breaker of simplified and inexpensive construction incorporating a snap action switch operating mechanism. It is also directed to an arrangement for assemblying a plurality of circuit breaker poles and/or switches to provide a simplified circuit breaker package having increased versatility.

Most conventional magnetic type electrical circuit breakers do not incorporate a snap action device for opening and closing the circuit breaker contacts. As a result, they have the disadvantage that they do not exhibit the increased mechanical and electrical life which as is well-known accompanies snap action electrical current switching. In addition, their failure to open and close with a snap action has in the past limited the magnitude of the current which can be switched with most conventional circuit breakers. Attempts to increase a circuit breaker life and to increase the current handling capability of the circuit breaker have resulted in expensive operating mechanisms substantially increasing the overall cost of the breaker.

The circuit breaker of the present invention is provided with a novel spring assembly for opening and closing the circuit breaker contacts with a spring or snap action. As a result, the circuit breaker exhibits many of the desirable features of a switch while at the same time providing over current protection. Because of the snap action feature it is possible to construct the circuit breaker with a simplified and less expensive operating mechanism or toggle, thus substantially reducing the overall cost of the device. Furthermore, by substituting for the collapsible toggle a simplified rigid link and eliminating the overcurrent elements of the breaker, it is possible to provide an inexpensive mechanical switch fully compatible in design, construction and appearance with a circuit breaker. This lends itself to a unique packaging system wherein several independent mechanisms be they breakers or switches can be combined in a single housing. Since the switch and circuit breaker housings are identical, the package appearance is excellent and the assembly is susceptible to a variety of mounting arrangements. In addition to a versatile package assembly, the modular circuit breaker and switch construction make it possible to supply individual modules to the user which he can assemble as required. Any desired mix of breakers and/or switches can be assembled up to a practical limit of six or more.

Because of the versatility described above the present invention makes possible an assembly in which power switches and overload switches can be combined in one package. Each module includes a snap out handle permitting a change in handle color and if desired a light emitting diode may be incorporated in the handle to provide illumination. Finally, with the snap switch action the handle feel of the breaker is improved in such a way as to enhance its commercial acceptability to the trade.

In the present invention the'contact bar carrying the movable contact of the circuit breaker is connected to one end of a coil tension spring which acts as an over center spring to snap open and snap closed the circuit breaker contacts. One end of the movable contact bar is pivoted to a' movable actuator or carrier rotatably mounted on the circuit breaker frame and having an extension pivoted or pinned to the actuating mechanism or toggle mechanism of the circuit breaker. Movement of the toggle mechanism either during overcurrent collapse or under the influence of the circuit breaker handle during manual operation rotates the carrier causing the pivotal support for the contact bar to pass through the over center plane of the tension spring. During initial movement of the carrier the contacts remain closed due to the closing force of the over center spring and the movable contact only undergoes a small rolling and wiping action against the stationary contact. However, when the support point or contact bar pivot moves through the over center plane the coil spring exerts an opening force on the contact bar causing it to snap open under the influence of the tension spring. Similarly, when the handle is moved to the closed position, the toggle mechanism acts to rotate the carrier in the opposite direction where the support point or pivot point for the contact bar again passes through the over center plane of the tension spring changing the force exerted by the spring from an opening force to a closing force and immediately causing the contacts to snap closed.

The snap closure force exerted by the over center spring eliminates the need for any application of pressure by the toggle to the contact bar in order to keep the contacts closed. As a result, simplified toggle mechanisms may be employed while at the same time insur- I ing that adequate closure forces will be at all times exerted on the movable contact. Similarly, the snap closure feature makes it possible to substitute a rigid link for the toggle actuating mechanism so that the same basic structure may be employed in a similar configuration as a simple snap action switch. The basic structure may be manufactured with the same overall configuration as individual modular units and these may be combined in single multi-pole type packages to provide a package or assembly which exhibits both snap action switching and over current protection features.

It is, therefore, one object of the present invention to provide an improved circuit breaker incorporating a snap acting movable contact.

Another object of the present inventionis to provide an improved electro-magnetic circuit breaker capable of switching increased current.

Another object of the present invention is to provide an over current protection device which also may be used as a snap action switch.

Another object of the present invention is to provide a simplified and inexpensive switch construction which may be used with electrical circuit breakers.

Another object of the present invention is to provide a modular package assembly incorporating both circuit breakers and switches.

Another object of the present invention is to provide an improved magnetic circuit breaker incorporating a simplified and less expensive toggle actuating mechanism for the movable contact bar of the circuit breaker.

Another object of the present invention is to provide an improved circuit breaker incorporating a light emitting diode display device in the operating handle.

Another object of the present invention is to provide an improved module construction which may be used both for over current protection and power switching.

These and further objects and advantages of the invention will be more apparent upon reference to the following specification, claims and appended drawings wherein:

FIG. 1 is a front elevation of a snap acting circuit breaker constructed in accordance with the present invention and with parts broken away and parts omitted to illustrate the internal operating mechanism of the breaker.

FIG. 2 is an end view of the circuit breaker of FIG. 1.

FIG. 3 is a perspective view of the snap switch contact assembly forming a part of the circuit breaker of FIGS. 1 and 2.

FIG. 4 is a perspective view of a portion of the collapsible toggle mechanism of the circuit breaker of FIG. 1.

FIG. 5 is a view of the circuit breaker of FIG. 1 showing it in the closed position.

FIG. 6 is a view of the circuit breaker of FIG. 1 showing it in the trip free position.

FIG. 7 is a perspective view of the housing or module for the circuit breaker of FIG. 1 and showing a display diode in the circuit breaker handle.

FIG. 8 is a side view of the circuit breaker handle incorporated in the module of FIG. 7.

FIG. 9 is a rear view of the circuit breaker handle illustrating the manner of mounting the light emitting display diode.

FIG. 10 is a side view of a complete module with parts broken away to illustrate the manner in which the handle is assembled in the module.

FIG. 11 is a partial cross section through the module again illustrating the handle construction.

FIG. 12 shows a modified construction in which a single housing incorporates three independent mechanisms constructed in accordance with the present invention.

FIG. 13 shows a power switch constructed in accordance with the present invention.

FIG. 14 is a front view showing the manner in which individual modules of the type illustrated in FIG. 7 may be assembled to form a package.

FIG. 15 is a side view of the assembly of FIG. 14.

FIG. 16 is anend view of the module assembly of FIGS. 14 and 15 and FIG. 17 illustrates a modified toggle mechanism which may be incorporated into the circuit breaker of FIG. 1.

Referring to the drawings, the novel circuit breaker of the present invention is generally illustrated at 10 in FIGS. 1 and 2. The circuit breaker is illustrated in FIG. 1 in the contacts open or off position. The circuit breaker 10 comprises a housing of suitable electrical insulating material such as plastic or the like with the lower portion or housing base illustrated at 12. Passing through base 12 of the housing are a pair of

terminals

14 and 16 by means of which the circuit breaker is electrically connected to an external circuit to be switched and/or protected against an over current. Terminal 16 is bent over as at 18 and mounted on this portion of the terminal is the stationary circuit breaker contact 20. Terminal 14 is connected by an electrical lead 22 to one end of an over current coil 24. The coil is mounted on a coil frame 26 and in the preferred embodiment surrounds a delay tube a portion of which is illustrated at 28. The other end of the coil is connected by a flexible lead 30 to an electrically conductive carrier 32 and by way of a movable contact bar 34 to the movable contact 36 mounted on the contact bar. When

electrical contacts

20 and 36 close or engage, an electrical circuit is completed between

terminals

14 and 16 by way of the over current coil 24.

The coil support frame 26 is in turn supported from a main frame generally indicated at 38 comprising a pair of spaced, flat parallel plates 40 and 42 joined by a plurality of pins, two of which are illustrated at 44 and 46 in FIG. 1. As best seen in FIG. 2 a handle link 48 is pivoted about pin 46 so that it is free to rotate about this pin. The inner end of the handle link 48 is pivoted by a pin 50 as best seen in FIG. 1 to the other end of a collapsible toggle generally indicated at 52. The toggle comprises an upper link 54 having its lower end telescopically received within the upper end of a lower link 56. Carried by lower link 56 is a toggle latch 58 having an extension 60 turned over to form a trip tab 62.

Supported within the main frame is an armature 64 having an extension 66 which extends over to adjacent a pole piece 68 of the over current coil 24. Armature 64 is pivoted to rotate about a pin 70 and includes a counterweight 72 and a toggle trip extension 74. When an over current passes through coil 24 armature extension 66 is attracted to the pole piece 68 and the armature 64 rotates about pin 70 so that extension 74 engages and moves trip tab 62 releasing the trip sear permitting the toggle to collapse under the influence of a toggle spring (not shown) in a well-known manner. This causes

contacts

20 and 36 to separate to open the circuit between

terminals

14 and 16.

The details of the latch mechanism 58 are illustrated in FIG. 4. The latch comprises a pin 76 rotatably mounted in lower toggle link 56 to which is attached the latch extension 60 and tab 62. Sear pin 76 is cut away or notched as at 78 to a semicircular cross section so that when rotated in the counterclockwise direction as viewed in FIG. 1 it clears link 54. This link is provided with a cooperating groove 80 which normally receives a portion of pin 76 adjacent notch 78 so that with the pin 76 received in the notch link 54 cannot further telescope into link 56 to collapse the toggle. However, when tab 62 and pin 76 to which it is attached is rotated in a counterclockwise direction under the urging of armature extension 74, pin 76 rotates into a position such that it clears groove 80 and upper link 54 is free to further telescope into lower link 56 to collapse the toggle.

Lower toggle link 56 is connected by a pivot pin 82 to a snap switch assembly generally indicated at 84 and illustrated in perspective in FIG. 3. More specifically, pin 82 connects the toggle link to a carrier 86 comprising

side plates

88 and 90 joined by an integral top plate 92. Flexible lead 30 is preferably soldered to the top plate 92 of the preferably brass carrier 86. Carrier 86 includes a pair of upwardly extending tabs 94 and 96 apertured as at 98 and 100 to receive pin 82.

Side plates

88 and 90 include

downward extensions

102 and 104 which have turned over portions at their lower ends defining outward extensions or .wings 106 and 108. The ends of the

carrier plates

88 and 90 are turned over as at 110 and 112 and these ends are provided with grooves 114 and 116'for receiving and pivotally supporting the ends of contact bar 34.

Contact bar 34 comprises an outer end 118 on the under side of which is mounted the movable contact 36. This end is provided with an aperture 120 as best seen in FIG. 3 through which passes and is hooked one end of a coil tension spring or over center spring 122. A similar hook 124 passes around and secures the other end of spring 122 to the stationary cross pin 44. The other end of contact bar 34 is bifurcated to define a central slot 126 as best seen in FIG. 2 between the spaced

contact bar legs

128 and 130. The extreme ends of these legs are received in the

grooves

114 and 116 of the turned over ends 110 and 112 of carrier 86 so that the contacting edges of contact bar 34 in the grooves act as pivot points about which the contact bar 34 may pivot in relation to carrier 86. Spring 122 under tension retains the edges of

contact bar legs

128 and 130 securely retained in the groovesjAt the same time, carrier 86 is free to pivot relative to the main frame 38. As best seen in FIG. 1 each of the main frame side plates 40 and 42 is provided with a curved cutout portion such as that illustrated at 136 in FIG. 1 against which bear the rear edges of the carrier projections or wings 106 and 108. Again, spring 122 under tension urges the carrier wings into engagement with the cutout in the main frame so that the contact points of the wings with the main frame cutout portions form pivot points for pivotal movement of carrier 86 relative to the frame. The frame is positioned by a pair of projections on each of the side plates such as the projection 138 engaging the edge of a pair of bosses in the housing base 12 such as that illustrated at 140 in FIG. 1.

FIG. 5 shows the circuit breaker of FIG. 1 in the closed position; that is, with the movable contact 36 of the contact bar 34 engaging the stationary contact 20.

In FIG. 5 the handle link 48 has been moved in a clock-.

wise direction and a force has been exerted on the contact bar 34 by way of

toggle links

54 and 56 to close the contacts and complete the circuit through coil 24 by way of

terminals

14 and 16. FIG. 6 shows the circuit breaker 10 in the trip free position. In the position illustrated in FIG. 6 the trip tab 62 has been rotated in a counterclockwise direction by the armature extension 74 releasing the sear illustrated in FIG. 4 and permitting the toggle to collapse. In FIG. 6 the toggle is shown collapsed with the link 54 fully telescoped into link 56, opening the contacts and 36 and interrupting the electrical current flow through coil 24.

In operation, FIG. 1 shows the contacts in the open position with the over center spring 122 holding them open. In thisposition the pivot point of the contact bar 34 formed by the heel of the contact bar engaging in the

actuator grooves

114 and 116 is below the central plane of the over center spring so that the resulting force exerted by the spring on the contact bar is in an open direction. In FIG. 5 handle link 148 has been manually moved to a closed position and a first force has been exerted through the toggle and by way of pin 82 on the carrier 86 causing the carrier to rotate in a clockwise direction from the position of FIG. 1 about the pivot point for the carrier defined by the engagement of the wings 106 and 108 with the curved cutouts 136 in the main frame 38. At a predetermined point of rotation of the carrier 86 by the pin 82 the carrier is rotated sufficiently in a clockwise direction such that the heel of the contact bar 34 passes through the horizontal central plane of the spring and when this happens the force exerted by the spring on the contact bar 34 changes from an opening force to a closing force causing the contact 36 to snap into engagement with stationary contact 20. During initial rotation of the carrier, before movement through the over center plane of its heel support, movement of the contact 36 is minimal.

When the contacts are manually open the operation is just the reverse, i.e., the force exerted through the toggle mechanism by pin 82 on the carrier 86 is in a counterclockwise direction causing the contact bar heel support grooves of the carrier to move back through the over center plane so that when they pass through this plane the contact force becomes an opening face and the contacts snap open. Again, initial movement of contact 36 is minimal but the contact does undergo a slight rolling and wiping action before snapping open which action provides improved electrical continuity through the contacts when they are later closed. The operation is essentially similar when the toggle is tripped, i.e., the toggle mechanism collapses under the influence of a toggle spring (not shown) in a well-known manner with pin 82 pulling on the carrier 86 to rotate in a counterclockwise direction passing the heel support grooves through the over center plane to cause contact 36 to snap open from stationary contact 20 under the opening force of the over center spring.

FIG. 7 shows a portion of a circuit breaker housing 142 for the circuit breaker 10 of FIG. 1. Mounted on the front face 144 of the housing is a rocker actuator or handle 146 with on and off indicia printed on it.'Carrier by the center of the handle and projecting slightly outwardly from it is an indicator light 148 in the form of a light emitting diode.

FIG. 10 illustrates the housing 142 as a two-piece construction and comprising the base 12 previously described telescopically received in a hollow body 150. If desired body 150 may be provided with

extensions

152 and 154 having roughened or

serrated ends

156 and 158 which cooperate with a flange 160 for mounting the circuit breaker module in a panel as more fully shown and described in assignees copending application Ser. No. 172,632 filed Aug. 18, 1971. Body 150 is preferably made of resilient electrically insulating plastic material and is provided with a plurality of apertures 162 which receives tabs 164 extending outwardly from base 12 to securely lock the base and body together to form the unitary housing 142. It is understood that the circuit breaker mechanism is initially mounted on the base 12 and the base is then slid into body 150 until the tabs 164 pass into apertures 162 locking the two parts together.

Rocker actuator or handle 146 is provided with a pair of L-shaped grooves one of which is illustrated at 166 in FIG. 10 which receives corresponding stub pins 168 and 170 which extend inwardly from the body and into the grooves of the handle actuator as best seen in FIG. 11 which is a partial cross section taken along line 1 1-11 of FIG. 10. Handle actuator 146 is additionally provided with slots such as slot 170 in FIG. 10 which slide overand receive a pin 17 2 passing through the apertures 174 of handle link 148. When rocker handle 146 is manually rocked back and forth the handle link 148 moves between the opened and closed positions illustrated in FIGS. 1 and 5, respectively.

FIGS. 8 and 9 show the details of the construction of rocker handle 146. FIG. 8 is a side view and FIG. 9 is a rear or inside back view of the rocker handle. It is preferably made of a suitable electrically insulating plastic material and is provided with a central cavity 174 adapted to receive the ends of a pair of

electrical leads

176 and 178. These flexible leads provide electrical connection to the light emitting diode 148 projecting from the cavity 174 through a suitable aperture in the rocker so that it is viewable from the front surface 180. The light emitting diode is secured in the aperture in the rocker handle by a suitable adhesive of electrically insulating material such as epoxy or the like as indicated at 182 in FIG. 9. If desired, a current limiting resistor (not shown) may be connected in series with one of the

leads

176 and 178 to prevent excessive current flow through the light emitting diode 148. It is understood that the diode forms an indicator light and by way of example only may be used to provide an optical indication as to whether the circuit breaker contacts are opened or closed. It may be used with an auxiliary switch of the type shown and described in assignees U.S. Pat. No. 3,501,606.

As previously indicated, the structure of the present invention readily lends itself to a variety of packages or module assemblies. FIG. 12 shows a modified housing construction 184 in which three switching type circuit breakers l3 constructed in accordance with the present invention and more particularly in accordance with the mechanism illustrated in F IG. 1 may be combined in a single housing with the

respective actuators

186, 188 and 190. Alternatively, one or more of the actuators may operate a switch construction of a type shown in FIG. 13.

FIG. 13 shows a switch constructed in accordance with the present invention. In FIG. 13 like parts bear like reference numerals and the switch generally indi cated at 184 in FIG. 13 comprises the main frame 38, handle link 48, actuating pin 82, stationary contact 20, movable contact 36, contact bar 34, carrier 86 and over center spring 122. The switch 184 is in all respects identical to the circuit breaker of FIG. 1 with the ex-' ception that the over current apparatus including the coil and armature have been omitted and a single rigid link 186 is substituted for the toggle mechanism 52. The switch 184 of FIG. 13 exhibits the same snap opening and snap closure features as the circuit breaker 10 of FIG. 1 when the actuator handle 48 is moved between the position illustrated in FIGS. 1 and 5. Thus, it is seen that the present invention provides a construction which can be used as a circuit breaker and by a minimum of modification as a simple snap acting switch, both motable in the same housing such as the housing 142 of FIG. 7 or both incorporated in a single housing such as the housing 184 in FIG. 12 and both operable by means of the same type of actuator such as the actuator 142 or the

actuators

186, 188 and 190 of FIG. 12.

FIGS. 14, and 16 show a preferred packaging assembly in which circuit breakers of the type illustrated in FIG. 1, switches illustrated in FIG. 13 or both may be combined as individual modules into a multi-module assembly. FIG. 14 shows a four module assembly generally indicated at 196 comprising a circuit breaker 198 and three

switches

200, 202 and 204. Both the circuit breaker 198 and all three

switches

200, 202 and 204 are mounted in identical housings 142 of the type previously described and the circuit breaker 198 has an operating mechanism of the type illustrated in FIG. 1 and the

switches

200, 202 and 204 each have operating mechanisms of the type illustrated in FIG. 13. The modules are mounted between

end plates

206 and 208 to form the complete package 196. The right-hand end plate 208 has a pair of projections indicated by dashed lines at 210 and 212 and the left-hand plate 206 has corresponding holes indicated by dashed lines at 214 and 216. Each of the modules is provided on its right side as illustrated in FIGS. 14 and 15 with holes 218 and 220 for receiving corresponding 'pins, the switch 204 illustrated in FIG. 16 receiving the

pins

210 and 212 of end plate 208. On the left-hand side each module is provided with

pins

222 and 224 corresponding to the

pins

210 and 212 of end plate 208. The

pins

222 and 224 on the last module, i.e., circuit breaker 198, are received in the

holes

214 and 216 in the left-hand end plate 206. The cooperating pins and holes act to align and to retain the assembly together. By using the pin-recess system molded integral with the module housing and end plate, additional parts such as nuts and screws and the like are not required. The pins are preferably split to permit a tight interference or friction fit in the aligned recess on hole of the next module.

FIG. 17 shows a modified toggle link construction which may be substituted for the toggle mechanism 52 in the circuit breaker of FIG. 1. The latch pin 58 and sear pin 76 are of the same construction as previously described. An upper link 232 in FIG. 17 which replaces the link 54 in the mechanism of FIG. 1 is provided with an outwardly extending cam 234 which bears on the sear pin 76 and keeps the upper link 232 rigid with respect to the lower link 234 in FIG. 17 which replaces the lower link 56 in the mechanism of FIG. 1. Upper link 232 is pivotally joined to lower link 234 in FIG. 17 by a pin 236 which passes through the links. When latch 58 is rotated, the slot in sear pin 76 clears the cam 234 permitting the toggle mechanism 230 to collapse through rotation of upper link 232 about pin 236 in the direction of the arrow 238 in FIG. 17. Again, the collapsible toggle mechanism 232 is a relatively simplified and inexpensive construction and this is made possible by the snap switch feature of the circuit breaker of FIG. 1 which requires no complex and extensive toggle mechanism to insure proper closure of the switch contact when the handle link 48 is moved to the contact closed position.

It is apparent from the above that the present invention provides an improved circuit breaker construction incorporating a snap switch feature. Through the use of a snap switch it is possible to use the circuit breaker of FIG. 1 both as an over current protector and a power current switch. By providing snap closure and snap opening of the circuit breaker contacts, higher currents may be manually switched. At the same time, the simplified snap switch feature makes possible the use of a simpler and less expensive collapsible toggle mechanism for actuating the movable contact of the breaker. Also disclosed is a modified construction in which the circuit breaker is in an inexpensive manner converted into a simple switch by eliminating the over current construction including the coil and armature and substituting for the collapsible toggle a single rigid link. Because of the complete compatibility of this switch construction with the overall circuit breaker construction it is further possible by the present invention to com bine independent elements with separate circuit breaking and switching functions into a single package, preferably of modular construction. The snap switch feature is brought about by a simplified over center single toggle spring construction in combination with a mechanism actuated carrier. Thus, the present invention provides an improved circuit breaker, switch and housing assembly possessing a wide versatility to suit the desires of the user. If desired, the individual modules may be sold separately and readily and simply assembled into the package of FIG. 14 for example by the user as he desires. The friction pins and recesses insure a reasonably permanent assembly and in combination with the end plates present a fully cooperative modular construction and one which is of a pleasing appearance.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are, therefore, intended to be embraced therein.

What is claimed is:

l. A circuit breaker comprising a support, an overcurrent sensor on said support, a collapsible toggle coupled to said sensor and adapted to, be tripped by said sensor in response to an overcurrent, a movable carrier coupled to said toggle and movable between first and second positions in response to movement of said toggle, a contact movably mounted on said carrier and movable between open and closed positions, and an overcenter spring coupling said movable contact to 10 said support for moving said contact between said open and closed positions with a snap action in response to movement of said carrier by said toggle. I

2. A circuit breaker according to claim 1 wherein said overcurrent sensor comprises an overcurrent coil and armature.

3. A circuit breaker according to claim 1 wherein said toggle comprises a pair of telescoping links.

4. A circuit breaker according to claim 1 wherein said toggle comprises a pair of pivotally joined links.

5. A circuit breaker according to claim 1 wherein said toggle comprises a pair of relatively movable links, said links being held against relative movement by a rotatable sear pin.

6. A circuit breaker according to claim 5 wherein said sear pin includes a cut away portion whereby rotation of said sear pin releases said links for relative movement.

7. A circuit breaker according to claim 1 including a contact bar, said movable contact being on said contact bar and said overcenter spring acting on said contact bar.

8. A- circuit breaker according to claim 7 wherein said carrier is rotatable, and means pivotally supporting said contact bar on said carrier.

9. A circuit breaker according to claim 8 wherein said movable contact is mounted adjacent one end of said contact bar, said contact bar being pivotally mounted on said carrier adjacent its other end.

,(s mano- Pnizxr. OFFICE '1 v h a 7 T CERTIFLCAiE OH CQRRLCTLOR Patent 210. 3,806,848 mama April 23, 1974 O Inventor) George S. Harper and John Richard Shand It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

. The name of the assignee Airpax Erectronics Incorporatefi should be included in the above identified patent.

. Signed and sealed this 22nd day of October 1974.

v (SEAL) Attest:

McCOY M. GIBSON: JR. Attesting- Officer c. MARSHALL lfiANN Commissioner of Patents is PJJB T CFFZCE 5 ID-ZZTIQS-L'Ai CERTKFIQXTE 0 F CORRECTEQN Eatent 21m 3,806,8 4 23 m d r-

i1

23, 1974.

e It is certified that errnr appears in the above-ddentlfled patent and that said Letters Patent are hereby corrected as shown below:

. The name of the assignee w Air ax Electrsnics lrmor fiffitd M J should be included in the above identified gatemto Signed and sealed this 22nd day of October 197 (SEAL) Attest:

- McCOY M. GIBSONLJR. c. MARSHA-LL IDJANN -Attesting-Officer Cummissioner of Patents

Claims

1. A circuit breaker comprising a support, an overcurrent sensor on said support, a collapsible toggle coupled to said sensor and adapted to be tripped by said sensor in response to an overcurrent, a movable carrier coupled to said toggle and movable between first and second positions in response to movement of said toggle, a contact movably mounted on said carrier and movable between open and closed positions, and an overcenter spring coupling said movable contact to said support for moving said contact between said open and closed positions with a snap action in response to movement of said carrier by said toggle.

8. A circuit breaker according to claim 7 wherein said carrier is rotatable, and means pivotally supporting said contact bar on said carrier.