Circuit breaker with arc chamber screen

Claim 2

A circuit breaker comprising a housing, stationary and movable contacts in said housing, a handle, a collapsible toggle coupling said handle to said movable contact, overcurrent means coupled to said toggle for tripping said toggle, an arc chamber in said housing substantially surrounding said contacts, said arc chamber comprising heat insulating baffles on five sides of said chamber and a metal shoe on a remaining side of said chamber, one of said five sides of said chamber comprising both a baffle and a wire mesh screen, said housing having an arc gas vent adjacent said contacts for venting arc gases from the area of said contacts to atmosphere, said wire mesh screen being made of temperature and corrosion-resistant material and overlying said vent, said screen having a wire diameter size of from 0.028 to 0.032 inch, with the center-to-center spacing of said wires being from 1/14th to 1/18th of an inch.

Claim 3

A circuit breaker according to claim 1 wherein said screen is made of stainless steel.

Claim 4

A circuit breaker according to claim 2 wherein said screen is made of 0.032 inch diameter wire on 1/16th inch centers.

Claim 5

A circuit breaker according to claim 2 wherein said screen is made of 0.032 inch diameter wire on 1/14th inch centers.

Claim 6

A circuit breaker according to claim 2 wherein said screen is made of 0.032 inch diameter wire on 1/18th inch centers.

Claim 7

A circuit breaker according to claim 2 wherein said screen is made of 0.028 inch diameter wire on 1/18th inch centers.

Claim 8

A circuit breaker according to claim 2 wherein said screen is made of stainless steel selected from the group consisting of type 302, type 304, type 305, type 410 and type 430.

Claim 9

A circuit breaker according to claim 7 wherein said screen is made of type 302 stainless steel.

Claim 10

A circuit breaker comprising a housing formed of two mating sections, a pair of relatively movable contacts in said housing, a handle, a collapsible toggle coupling said handle to one of said contacts, overcurrent means coupled to said toggle for tripping said toggle, an arc chamber in said housing substantially surrounding said contacts, said arc chamber comprising heat insulating baffles on five sides of said chamber and a metal shoe on a remaining side of said chamber, one of said five sides of said chamber comprising both a baffle and a wire mesh screen of temperature and corrosion-resistant material, a plurality of spaced projections on one of said housing sections extending toward the other section, a plurality of cooperating spaced projections on said other section extending toward said one section, said projections on said other section being in alignment with but outwardly spaced from the projections on said one section whereby arc gases may escape from said housing, not only by passing between adjacent projections on a housing section, but also between the aligned projections of the respective housing sections, said wire mesh screen being located between said contacts and said projections, said screen having a wire diameter size of from 0.028 to 0.032 inch, with the center-to-center spacing of said wire being from 1/14th to 1/18th of an inch.

Claim 11

A circuit breaker comprising a housing formed of two mating sections, a pair of relatively movable contacts in said housing, a handle, a collapsible toggle coupling said handle to one of said contacts, overcurrent means coupled to said toggle for tripping said toggle, an arc chamber in said housing substantially surrounding said contacts, said arc chamber comprising heat insulating baffles on five sides of said chamber and a metal shoe on a remaining side of said chamber, one of said five sides of said chamber comprising both a baffle and a wire mesh screen of temperature and corrosion-resistant material, a plurality of spaced projections on one of said housing sections extending toward the other section, a plurality of cooperating spaced projections on said other section extending toward said one section, said projections on said other section being in alignment with but outwardly spaced from the projections on said one section whereby arc gases may escape from said housing, not only by passing between adjacent projections on a housing section, but also between the aligned projections of the respective housing sections, said wire mesh screen being located between said contacts and said projections, said screen having a wire diameter size of from 0.028 to 0.032 inch, with the center-to-center spacing of said wire being from 1/14th to 1/18th of an inch.

Claim 12

A circuit breaker according to claim 9, including a flange on the breaker section having the innermost of said projections whereby arc gases venting between aligned projections are deflected by said flange.

Claim 13

A circuit breaker according to claim 10, wherein said projections on said first and second sections overlap.

Claim 14

A circuit breaker according to claim 9, wherein said screen is made of stainless steel containing between 12 and 30 percent by weight of chromium.

Claim 15

A circuit breaker according to claim 12, wherein said stainless steel contains from 8 to 13 percent by weight of nickel.

Claim 16

A circuit breaker according to claim 12, wherein said stainless steel contains from 11.5 to 20 percent by weight of chromium.

Claim 17

A circuit breaker according to claim 14, wherein said stainless steel contains 17 to 19 percent by weight of chromium.

Claim 18

A circuit breaker according to claim 15, wherein said stainless steel contains 8 to 10 percent by weight of nickel.

Claim 19

A circuit breaker according to claim 1 including an arc gas exhaust chute in said housing, said wire screen permitting fluid communication between the interior of said arc chamber and said exhaust chute.

Claim 20

A circuit breaker according to claim 1 including an arc gas exhaust chute in said housing, one of said five baffles at least substantially closing off said arc chamber to the exhaust of gases through said exhaust chute.

Claim 21

A circuit breaker according to claim 1 wherein a plurality of metallic arc suppressors are supported by a pair of said five baffles adjacent the path of said movable contact.

Claim 22

A circuit breaker according to claim 19 wherein said arc suppressors are arranged in groups of different length.

Claim 23

A circuit breaker according to claim 19 wherein said arc suppressors are of different thickness.

Claim 24

A circuit breaker according to claim 21 wherein the arc suppressors adjacent said stationary contact are of greater thickness than those more remote from said stationary contact.

Claim 25

A circuit breaker according to claim 1 wherein one of said baffles is slotted to receive a bifurcated contact bar carrying said movable contact.

Claim 26

A circuit breaker according to claim 1 wherein said baffles are made of electrical and heat insulating material.

Claim 27

A circuit breaker according to claim 24 wherein said baffles are made of vulcanized fiber.