Pressure actuated electrical bypass circuit for a high voltage bushing

Claim 2

A bushing for connecting electrical apparatus to the conductive member of a high voltage cable terminator, said bushing including: a dielectric housing having a passage, an electrically conductive contact positioned within said passage, said contact being adapted to electrically engage the conductive member in the terminator, a frangible member within said passage, means for connecting said contact to the electrical apparatus, and electrical bypass means within said bushing for connecting said contact to the conductive member when the pressure of the gas produced by the heat of the prestrike arc on close-in is sufficient to break the frangible member.

Claim 3

The bushing according to claim 1 wherein said electrical bypass means comprises a cylindrical tube positioned with said passage and having a section at one end for electrically engaging the terminator and a section at the other end for electrically engaging said contact.

Claim 4

The bushing according to claim 2 including an insulating sleeve positioned with said cylindrical tube for supporting said contact for axial movement within said passage.

Claim 5

The bushing according to claim 3 including a cylindrical section of insulating material mounted on said contact and being connected to said frangible member to confine the gases produced on prestrike to the inlet end of said passage.

Claim 6

The bushing according to claim 1 wherein said electrical bypass means includes a cylindrical section to provide electrical communication with the terminator and a sleeve mounted on said frangible member and extending into said cylindrical section whereby on rupture of said frangible member said sleeve will be forced into engagement with said section.

Claim 7

The bushing according to claim 5 including means within said cylindrical section for clamping the terminator in said bushing on rupture of said frangible member.

Claim 8

The bushing according to claim 6 wherein said clamping means responds to the pressure of the gases produced on fault close in.

Claim 9

The bushing according to claim 1 wherein said frangible member supports said contact within said passage.

Claim 10

The bushing according to claim 8 wherein said contact is movable into engagement with said bypass means on rupture of said frangible member.

Claim 11

A voltage bushing for connecting electrical apparatus to the conductive probe of a high voltage cable terminator, said bushing including: a dielectric housing, an electrically conductive tubular contact positioned within said housing, said contact being open at one end to electrically engage the conductive probe in the terminator on close-in, a gas evolving arc-quenching tube surrounding said contact and extending beyond the open end of said contact, a frangible member within said housing, said frangible member confining the gases produced by the prestrike arc on close-in within said contact, means within said housing for electrically connecting said contact to the electrical apparatus, and electrically conductive bypass means within said bushing for electrically connecting the electrical apparatus to the conductive probe when the pressure of the gas within the contact is sufficient to rupture the frangible member and allow electrical engagement of said electrically conductive bypass means with said probe.

Claim 12

A voltage bushing for connecting electrical apparatus to the conductive probe of a high voltage cable terminator, said bushing including: a dielectric housing, an electrically conductive tubular contact positioned within said housing, said contact being open at one end to electrically engage the conductive probe in the terminator on close-in, a gas evolving arc-quenching tube surrounding said contact and extending beyond the open end of said contact, a frangible member within said housing, said frangible member confining the gases produced by the prestrike arc on close-in within said contact, means within said housing for electrically connecting said contact to the electrical apparatus, and electrically conductive bypass means within said bushing for electrically connecting the electrical apparatus to the conductive probe when the pressure of the gas within the contact is sufficient to rupture the frangible member and allow electrical engagement of said electrically conductive bypass means with said probe.

Claim 13

The bushing according to claim 10 wherein said electrical bypass means comprises a hollow tubular member positioned within said bushing and having a section at one end for electrically engaging the probe and a section at the other end for electrically engaging said contact.

Claim 14

The bushing according to claim 10 wherein said frangible member includes a cylindrical section mounted on said contact and extending partially into said gas evolving tube.

Claim 15

The bushing according to claim 11 wherein said frangible member includes a cylindrical section surrounding one end of said contact extending through the section at the other end of the electrical bypass means and partially into the arc-quenching gas evolving tube.

Claim 16

The bushing according to claim 13 including means positioned between the cylindrical section and the arc-quenching tube for sealing the contact from the reduced diameter section of the electrical bypass means.

Claim 17

The bushing according to claim 10 wherein said electrical bypass means includes a cylindrical section to provide electrical communication with the probe and a sleeve surrounding said frangible member and extending into said cylindrical section whereby on rupture of said frangible member, said sleeve will be forced outwardly into engagement with said cylindrical section.

Claim 18

The bushing according to claim 10 wherein said bypass means includes a clamp assembly positioned to respond to the increase of pressure within said bushing on rupture of said frangible member to clamp the probe in the bushing.

Claim 19

The bushing according to claim 10 wherein said frangible member is integral with and forms an extension of the said arc-quenching tube.

Claim 20

The bushing according to claim 15 including an arc-quenching sleeve secured to said cylindrical section at the open end of the passage in said bushing and a clamp assembly mounted within said cylindrical section and bearing against said arc-quenching sleeve, said assembly being positioned to respond to the pressure of the gas within the bushing on rupture of said frangible member to break said sleeve and move into clamping position with respect to said probe.