High voltage disconnect switch with switch interrupter having an actuating arm actuated by an arc horn with a spring catch

Abstract

A high voltage air disconnect switch having an electrical load interrupter unit responsive to the opening of the high voltage air break disconnect switch. The electrical load interrupter unit including an actuating arm is contacted, during the opening of the switch, by a moving arc horn attached to and in electrical circuit with a switch blade of the high voltage air disconnect switch. The moving arc horn has operatively attached a spring catch which engages the actuating arm with a physical holding force applied to an electric contact point between the actuating arm and the moving arc horn to firmly capture the interrupter actuating arm against the moving arc horn during opening of the switch to prevent any arc burning damage due to arcing between the actuating arm and the moving arc horn as the switch opens.

Claims

1. A high voltage air break disconnect switch comprising: a rotating switch blade operatively connected to a hinge contact member at one end of the rotating switch blade and in operative arrangement with a break jaw contact at the other end thereof, the high voltage air break disconnect switch having an open electrically non-conductive position and a closed electrically conductive position, the rotating switch blade including an integral hinge in operative electrical circuit arrangement with a high voltage electric power line conductor at the one end of the switch blade, the rotating switch blade at the other end thereof including a switch blade end in operative arrangement with a break jaw contact, the break jaw contact in operative electric circuit arrangement with the high voltage electric power line conductor, the switch blade end for contacting the break jaw contact during closing of the high voltage air break disconnect switch in the switch closed electrically conductive position and for losing contact with the break jaw contact during switch opening in the switch open electrically non-conductive position, an electric interrupting device for interrupting current flow including an actuating arm for tripping the electric interrupting device, a moving switch blade member fastened to the rotating switch blade and in operative electrical circuit arrangement therewith, the moving switch blade member having a contact point for contacting the actuating arm during opening of the high voltage air break disconnect switch to trip the electric interrupting device to cause interruption of current flowing through the switch and for establishing a parallel electrical current path through the moving switch blade member and the actuating arm to commute the electrical current of the high voltage air break disconnect switch to the electric interrupter device as the switch opens, a spring catch fastened to the moving switch blade member and the rotating switch blade and in operative electrical circuit arrangement with the moving switch blade member and the rotating switch blade, the spring catch configured to cooperate with the moving switch blade member to engage the outer periphery of the actuating arm with a spring holding force applied to the contact point to prevent arc burning damage due to arcing between the actuating arm and the moving switch blade member as the switch opens, wherein the spring catch has a predetermined shape for guiding and retaining the actuating arm on the contact point on the moving switch blade member as the switch opens during the commutation of the electrical current of the switch through the moving switch blade and the actuating arm to the electric interrupter device until an intended separation of the actuating arm and the moving switch blade member occurs after the electric interrupting device has interrupted the switch current, wherein the spring catch comprises a single electrically conductive spring wire, wherein the single electrically conductive spring wire is configured to apply a spring force to hold the actuating arm and the moving switch blade member together at the contact point, wherein the single electrically conductive spring wire includes a catch zone configured to trap the actuating arm by applying the spring force of the spring catch to hold the actuating arm and the moving switch blade member together at the contact point after the actuating arm enters a one-way catch opening of the catch zone, the one-way catch opening configured to let the perimeter of the actuating arm pass therethrough but blocks the perimeter of the actuating arm from exiting back in a reverse direction through the one-way catch opening and the catch zone is configured to continue to apply the spring force of the spring catch until the catch zone of the spring catch slides along the length of the actuating arm and off the end of the actuating arm upon the high voltage air break disconnect switch fully opening, and, wherein the catch zone is configured to trap the actuating arm to prevent any bouncing between the moving switch blade member and the actuating arm and to prevent the actuating arm from exiting the catch zone back in the reverse direction through the one-way catch opening during the opening of the high voltage air break disconnect switch.

2. The high voltage air break disconnect switch of claim 1, wherein the spring catch is made of spring tempered stainless steel.

3. The high voltage air break disconnect switch of claim 1, wherein the spring catch is made of 17 chrome-7 nickel heat treatable stainless steel.

4. The high voltage air break disconnect switch of claim 1, wherein the moving switch blade member comprises a moving arc horn.

5. The high voltage air break disconnect switch of claim 1, wherein the spring catch is attached to the moving switch blade member by screws.

6. The high voltage air break disconnect switch of claim 1, wherein the single electrically conductive spring wire is configured to form two oppositely disposed resilient spring guide fingers each extending from the attached moving switch blade member inwardly toward each other to form the catch zone with the one-way catch opening.

7. The high voltage air break disconnect switch of claim 6, further comprising a second electrically conductive spring wire, wherein the single electrically conductive spring wire and the second electrically conductive spring wire are configured to form the two oppositely disposed resilient spring guide fingers.

8. The high voltage air break disconnect switch of claim 6, wherein the single electrically conductive spring wire is further configured to form a V-shaped chute guide having surfaces for guiding the actuating arm towards the one-way catch opening.

9. The high voltage air break disconnect switch of claim 8, wherein the two oppositely disposed resilient spring guide fingers each extend from the one-way catch opening by retroverting away from each to other to form the surfaces of the V-shaped chute guide.

10. The high voltage air break disconnect switch of claim 6, wherein the actuating arm is tubular having a circular cross-section.

11. The high voltage air break disconnect switch of claim 10, wherein during the opening of the switch the two resilient spring guide fingers are configured to initially engage the outer circumference of the tubular actuating arm as the actuating arm passes through the one-way catch opening and enters the catch zone, the two resilient spring guide fingers are configured to hold the actuating arm by spring force so that the actuating arm is prevented by the two resilient guide fingers from exiting back through the one-way catch opening as the switch opens and to apply the spring force of the spring catch until the spring catch slides along the length of the tubular actuating arm and off the end of the actuating arm upon the high voltage air break disconnect switch fully opening.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) For a better understanding of the invention reference may be made to the accompanying drawings exemplary of the invention, in which:

(2) FIG. 1A is a perspective view of a prior art high voltage air break disconnect switch with an interrupter unit showing the switch in both the electrically closed and partially open position;

(3) FIG. 1B is an enlarged elevation view along the line 1B-1B of FIG. 1A in the partially open position of the switch;

(4) FIG. 2A is a perspective view of the high voltage air break disconnect switch of the present invention in both the electrically closed and open position;

(5) FIG. 2B is an elevation view along the line 2B-2B of FIG. 2A in the partially open position of the switch; and,

(6) FIG. 2C is an enlarged elevation view of the spring member of FIG. 2B.

DETAILED DESCRIPTION OF THE INVENTION

(7) FIG. 1A shows a prior art motorized in-line high voltage air break disconnect switch 10 including an attached electrical load interrupter unit 100. The switch 10 is shown as a vertical break disconnect switch and is described in the previously mentioned U.S. Pat. No. 9,881,755 B1 dated Jan. 30, 2018. This switch 10 includes a motor 12 for operating the switch. The switch 10 includes a rotating hinge contact end 14. The switch uses a polymer strain insulator 22 with other switch current carrying parts.

(8) Other common switch current carrying parts of the switch 10 includes vertically rotating switch blade 20. A hinge contact member 24 is included at the hinge end 18 of the switch 10 and is connected in circuit to a hinge terminal 38. The hinge contact member 24 includes a hinge pin 33 that switch blade 20 rotates about during opening and closing of the switch. The hinge end 18 of the switch 10 is mounted proximate one end 28a of the strain insulator 22. The switch 10 also includes a break jaw end 19 which is mounted proximate the other end 28b of the strain insulator 22 and a switch break jaw contact terminal 30. The switch break jaw contact terminal 30 includes an integral break jaw contact 32 for contacting the switch blade end 34 when the switch is closed. The switch 10 also includes jumpers 36a, 36b attached in the circuit respectively, to a hinge terminal 38 and the switch break jaw terminal 30. As shown in FIG. 1A, a transmission line 40 has been cut, resulting in two transmission line ends 42a, 42b. Each transmission line end 42a, 42b is respectively attached to strain cable fittings 43a, 43b and to shackles 44a, 44b. The switch 10 is applicable to electric power lines including transmission lines and distribution lines, for example. The shackles 44a, 44b respectively engage chain eye end fittings 46a, 46b at the ends 28a, 28b of the strain insulator 22. The transmission line 40 can support the in-line vertical air break disconnect switch 10 without the switch 10 being attached directly to a dedicated support structure, such as metal framework. The jumpers 36a, 36b carry the transmission line current in circuit with the switch blade 20 via the contacts 32 and 24.

(9) The electrical load interrupter unit 100 of the prior art switch in this embodiment is a vacuum interrupter attached to the switch break jaw terminal 30 as shown in FIG. 1A. An example of the internal mechanism of such a vacuum interrupter is disclosed in U.S. Pat. No. 10,242,825 B1 dated Mar. 26, 2019, by Peter M. Kowalik and Daniel J. Wolfe, entitled High Voltage Switch Vacuum Interrupter assigned to the present assignee, Cleaveland/Price Inc. The said U.S. Pat. No. 10,242,825 B1 is incorporated herein by reference in its entirety as though fully set forth. In addition to a vacuum interrupter, the present invention is also applicable to a sulfur hexafluoride gas (SF6) interrupter and an oil interrupter. The electrical load interrupter 100 includes housing 106 and a spring-loaded actuating arm 102 for actuating the internal mechanism, not shown in the drawings, containing springs within the housing 106. The spring-loaded actuating arm 102 is contacted by a moving arc horn 104 attached to and in electrical circuit with the movable switch blade 20 of the high voltage air disconnect switch 10. The spring-loaded actuating arm 102 typically is tubular, being hollow and having a circular cross-section. The moving arc horn 104 is operatively attached to the movable switch blade 20 as shown in FIGS. 1A and 1B. As mentioned, the bouncing problem with this arrangement when opening switch 10 between the actuating arm 102 and moving arc horn 104 is often experienced.

(10) As can be seen in FIGS. 2A, 2B and 2C, the moving arc horn 104 of the present invention has been modified from the prior art moving arc horn 104, shown in FIG. 1B, to include an operatively attached spring catch 110. With regard to FIGS. 2A, 2B and 2C, like numerals represent like components as shown in FIGS. 1A and 1B. The spring catch 110 when mounted on the moving arc horn 104 forms a catch and trap zone 116. The spring catch 110 contacts the actuating arm 102, as shown in FIG. 2C. The catch and trap zone 116 is bordered by two oppositely disposed resilient spring guide fingers 120a, 120b of the spring catch 110 and the contact point 108 of the arc horn 104. Each of the spring guide fingers 120a, 120b extend inwardly toward each other to form a catch and trap opening 118 at the entrance to the catch and trap zone 116. The spring guide fingers 120a, 120b at the catch and trap opening 118 are sized to allow the outer circumference of the actuating arm 102 to pass slidably through the catch and trap opening 118, by utilizing the elasticity of the spring guide fingers 120a, 120b to sufficiently spread apart from each other at the catch and trap opening 118, to permit the outer circumference of the actuating arm 102 to enter the catch and trap zone 116, upon opening of the switch. After the actuating arm 102 enters the catch and trap zone 116, the spring guide fingers 120a, 120b, elastically return to their original shape, thereby preventing the actuating arm 102 from exiting the catch and trap zone 116 transversely through the catch and trap opening 118. The catch and trap zone 116 then retains the actuating arm 102 via first and second spring force points 114a, 114b of the spring catch 110 at contact point 108 to prevent any bouncing between the moving arc horn 104 and the actuating arm 102 for constant physical and electrical contact, during opening of the switch 10. The spring force of the spring guide fingers 120a, 120b at the first and second spring force points 114a, 114b stays applied as the switch 10 opens, with switch blade 20 with the moving arc horn 104 attached to the blade 20 and the spring catch 110 attached to the moving arc horn 104, the spring catch 110 engages the actuating arm 102 and continued motion of the blade to the full 180 degree open position, not shown in the drawings, causes the spring catch 110 to slide off the end of the actuating arm 102 after the interrupter 100 has tripped to interrupt the current flow through the switch 10. The spring force of spring catch 110 at the catch and trap zone 116 stays applied until the actuating arm 102 is caused to slide off the end of the actuating arm 102 by normal operation of the switch 10.

(11) The two resilient spring guide fingers 120a, 120b preferably extend from the catch and trap opening 118 by retroverting away from each other to form a V-shaped chute guide 121 having chute guide surfaces 122 of the spring catch 110 with a wide chute guide opening compared to the catch and trap opening 118. The wide chute guide opening is shown in FIG. 2C at the entrance of the V-shaped chute guide 121 for enabling easy capture of the actuating arm 102 and guiding it to the catch and trap zone 116, during opening of the switch 10.

(12) As can be seen by reference to FIG. 2C, the spring catch 110 may comprise a designed wire form which in this embodiment is a single spring wire 112 that is bent as shown in FIGS. 2B and 2C. The single spring wire 112 forms the resilient spring guide fingers 120a, 120b. Screws 124a, 124b respectively attach the spring catch 110 to the moving arc horn 104 as shown in FIG. 2C. Also, as can be seen in FIG. 2C, the single spring wire 112 terminates at each end 126a, 126b. Of course, the spring catch 110 could comprise, for example, two spring wires to form the spring guide fingers without departing from the scope of the present invention, not shown in the drawings. The spring catch 110 may be made of spring tempered stainless steel, or 17 chrome-7 nickel heat treatable stainless steel, for example.

LIST OF REFERENCE NUMERALS

(13) 10 motorized in-line high voltage air break disconnect switch 12 motor 14 rotating hinge contact end 18 hinge end of 10 19 break jaw end 20 switch blade 22 polymer strain insulator 24 hinge contact member 28a one end of 22 28b other end of 22 30 switch break jaw contact terminal 32 break jaw contact 33 hinge pin 34 switch blade end 36a jumper 36b jumper 38 hinge terminal 40 transmission line 42a transmission line end 42b transmission line end 43a strain cable fitting 43b strain cable fitting 44a shackle 44b shackle 46a chain eye end fitting 46b chain eye end fitting 100 interrupter unit 102 actuating arm 104 moving arc horn 106 housing of interrupter unit 108 contact point of 104 110 spring catch 112 spring wire 114a first force point 114b second force point 116 catch and trap zone 118 catch and trap opening 120a first spring guide finger 120b second spring guide finger 121 V-shaped chute guide 122 chute guide surfaces 124a screw 124b screw 126a one end of 112 126b other end of 112

(14) Of course variations from the foregoing embodiment is possible without departing from the scope of the invention.