US3508178A

US3508178A - High voltage switch having auxiliary latch operating means for the current interrupter

Info

Publication number: US3508178A
Application number: US718428A
Authority: US
Inventors: Leonard V Chabala; Edward J Rogers
Original assignee: S&C Electric Co
Current assignee: S&C Electric Co
Priority date: 1968-04-03
Filing date: 1968-04-03
Publication date: 1970-04-21
Anticipated expiration: 1987-04-21
Also published as: GB1208853A

Description

April 21, 1970 L. VQCHA B ALA E TAL 3,503,173

HIGH VOLTAGE: SWITCH HAVING AUXILIARY LATCH OPERATING MEANS FOR THE CURRENT INTERRUPTER Filed April 5, 1968 3 Sheets-Sheet 1 April 21, 1970 .v. .cHABALA ETAL I 3,508,178

HIGH VOLTAGE SWITCH HAVING AUXILIARY LATCH OPERATING MEANS FOR THE CURRENT INTERRUP TER Filed April 5, 1968 3 Sheets-Sheet 2 April 1970 1.. V..CHABALA ETAL 3, HIGH VOLTAGE SWITCH HAVING AUXILIARY LATCH OPERATING MEANS FOR THE CURRENT INTERRUPTER Filed April 5, 1968 3 Sheets-Sheet 3 United States Patent 3,508,178 HIGH VOLTAGE SWITCH HAVING AUXILIARY LATCH OPERATING MEANS FOR THE CUR- RENT INTERRUPTER Leonard V. Chabala, Maywood, and Edward J. Rogers, Chicago, Ill., assignors to S & C Electric Company, Chicago, Ill., a corporation of Delaware Filed Apr. 3, 1968, Ser. No. 718,428 Int. Cl. H01h 3/02, 9/00, 31/00 US. Cl. 3351 12 Claims ABSTRACT OF THE DISCLOSURE A collapsible toggle linkage interconnects an auxiliary trip operator and the latch that restrains spring operated current interrupting means to permit resetting of the latch independently of return of the auxiliary trip operator to non-operated position and an auxiliary latch permits operation of the auxiliary trip operator only when a solenoid operator is energized.

This invention is an improvement over the construction disclosed in Lindell et al. Patent 3,116,391, issued Dec. 31, 1963.

In that patent there is disclosed a spring operated latch released mechanism for opening the contacts of current interrupting means connected in series with a disconnecting switch blade which is subsequently opened. The latch is released and the switch blade is swung to the open position by switch operating mechanism that has substantial inertia and requires a substantial time, particularly to release the latch. In the patent a solenoid operated auxiliary trip operator is arranged to release the latch separately from and in advance of its release by the switch operating mechanism. In that construction there is the possibility that the auxiliary trip operator may not return to its nonoperated position with the result that the latch is held in the unlatched position or is not permitted to reset. Further, the trip operator may be inadvertently caused to perform its function without the solenoid being operated. This may result in undesired tripping of the current interrupting means.

Among the objects of this invention are: To arrange for the return of the latch that holds current interrupting means against operation after it has been tripped by anxiliary operating means independently of the return of the auxiliary operating means to its non-operated position; to accomplish this by a collapsible toggle linkage interconnecting the auxiliary operating means and a lever that engages and releases the latch; to .prevent operation of the auxiliary operating means except on energization of a solenoid provided for this purpose; and to employ an auxiliary latch for preventing false operation of the anxiliary operating means which is moved to unlatched position on energization of the solenoid.

According to this invention a toggle linkage interconnects the solenoid operated auxiliary trip operator and the lever that releases the latch of the current interrupting means. After the latch has been released to open the contacts of the current interrupting means, the toggle linkage is arranged to collapse in order to permit the latch to reset and the lever to return to its non-operated position independently of the return of the trip operatorto its nonoperated position. An auxiliary latcli prevents operation of the auxiliary trip operator until the solenoid is energized whereupon the auxiliary latch is moved to unlatched position and the auxiliary trip operator is rotated to drive through the toggle linkage and rotate the lever that releases the latch of the current interrupting means.

In the drawings: FIG. 1 is a perspective view of a portion of a combination disconnecting switch and current 3,508,178 Patented Apr. 21, 1970 interrupter in which this invention is embodied. FIG. 2 is a top plan view of the collapsible toggle linkage employed in the construction shown in FIG. 1 and shows by full lines the non-operated position of the mechanism and by broken lines the operated position of the mechanism before collapse of the toggle linkage. FIG. 3 is a view, similar to FIG. 2 and shows by full lines the operated position of the toggle linkage which is shown by broken lines in FIG. 2, and by broken lines the collapsed position of the toggle linkage. FIG. 4 is a vertical sectional view taken generally along the line 44 of FIG. 2. FIG. 5 is a vertical sectional view taken generally along the line 5-5 of FIG. 1 and shows the details of construction of the flexible joint. FIG. 6 is a vertical sectional view taken generally along the line 6-6 of FIG. 1, certain parts being shown in elevation to illustrate the details of construction of the slip joint. FIG. 7 is a horizontal view taken generally along the line 77 of FIG. 6. FIG. 8 is a plan view of the solenoid operated linkage arranged to operate the auxiliary trip mechanism with a cam lock shown in the locked nonoperated position, certain parts being shown in section. FIG. 9 is a view, similar to FIG. 8, and shows the linkage on energization of the solenoid and with the auxiliary latch lever moved out of engagement with the cam lock. FIG. 10 is a view, similar to FIG. 9, and shows the final position of the linkage operated by energization of the solenoid.

In FIG. 1 the reference character 10 designates, generally, switch means which constitutes a portion of one phase of a three phase switch described in more complete detail in the patent above referred to. If desired, the switch means 10 can be employed for single phase operation. The switch means 10 includes a base 11. The operating means for the switch means 10 includes a rotatable insulator 12 that is suitably journaled at its lower end on the base 11 and has an arm 13 connected to an operating link 14. At its upper end the insulator 12 has an upstanding shaft 15 which extends through a metallic spring mechanism housing 16 that is held stationary by a current interrupter that is indicated, generally, at 17. Disconnecting switch blade 18 is rotatably mounted on the mechanism housing 16. It is arranged to be operated on rotation of the shaft 15 through a switch crank 19 that is connected by a link 20 to a clevis 21 which, in turn, is rotatably connected to an arm 22 that extends from the switch blade 18. On rotation of the insulator 12 by suitable operation of the operating link 14, the latch in the mechanism hous ing 16 is released to permit the current interrupter 17 to interrupt the circuit. Continued rotation of the insulator 12 causes the switch blade 18 to swing to open circuit position followed by recharging of the spring in the mechanism housing 16 which is held by a latch and reclosure of the contacts in the current interrupter 17 Because of the inertia of the rotatable insulator 12 and parts connected thereto, a substantial time is required for effecting the tripping of the latch in the mechanism housing 16 and opening of the contacts in the current interrupter 17. Accordingly, as disclosed in the patent above referred to, provision was made for tripping the latch by auxiliary operating means having substantially less inertia and therefore a lesser operating time than is required for the tripping of the latch by rotation of the insulator 12. While the auxiliary latch tripping mechanism of the above patent was satisfactory under normal operating conditions, it was found that its operation might be impaired under certain adverse operating conditions. In the event that, for some reason, the auxiliary trip operator did not automatically return to its non-operated position, the latch might be held in the operated position and would not be permitted to reset. Accordingly, the spring in the mechanism housing 16 would not be held against operation and the contacts in the current interrupter 17, which should have been held in the closed position, would be operated to the open position and thus proper operation of the switch means 10 would be interfered with. Also there was the possibility that the auxiliary trip mechanism intended to be operated on energization of a solenoid would be operated inadvertently which would cause a false operation of the switch means 10. In accordance with this invention provision is made for overcoming these possible improper operations through the use of auxiliary trip or independent operating means indicated, generally, at 23.

In FIGS. 2, 3 and 4 there is indicated at 24 an extension of the main latch for the spring in the mechanism housing 16 which is arranged to open the contacts in the current interrupter 17. When the main latch extension 24 is rotated from the full line position shown in FIG. 2 to the broken line position, the latch is operated to release the spring in the mechanism housing 16 to permit it to open the contacts of the current interrupter 17. As pointed out above, that operation can be effected through rotation of the insulator 12 but a substantial time is required to accomplish it. Using the auxiliary trip or independent operating means 23, the contacts in the current interrupter 17 can be opened in a relatively short time such as within 8 cycles of 60 cycle alternating current.

The main latch extension 24 is arranged to be engaged by a plastic nose 25 which is carried by an adjusting screw 26 which is threaded in the distal end of an arm 27 that forms a part of a trip lever which is indicated, generally, at 28. The trip lever 28 includes a shaft 29, FIG. 4, that is journaled in a cover 30 for the mechanism housing 16 and has fastened to its upper end an arm 31. The distal end of the arm 31 is connected by collapsible linkage means, indicated generally at 32, FIG. 2, to the distal end of an arm 33 which is secured to the upper end of a shaft 34 which is journaled in an extension 35 of the mechanism housing 16. The lower end of the shaft 34 is connected by a flexible joint, shown generally at 36 in FIG. 5, to a shaft 37 which is secured to the upper end of and is rotatable with an insulator 38. The insulator 38 has substantially the same length as the insulator 12 in order to provide the required degree of insulation for the mechanism housing 16 and energized parts connected thereto but it is substantially smaller in diameter since it is not required to transmit the torque required to be transmitted by the insulator 12.

In FIG. the details of construction of the flexible joint 36 are shown. The flexible joint 36 includes a sleeve 41 that is telescoped over the juxtaposed reduced diam- '

eter ends

42 and 43 of the

shafts

34 and 37. A key section 44 depends from the lower end of the shaft 34 for insertion in a slot 45 in the upper end of the shaft 37. Transverse apertures 46 and 47 are provided in the reduced

diameter ends

42 and 43 for receiving coil compression springs 48 and 49 that

urge detents

50 and 51 outwardly into

openings

52 and 53 near the upper and lower ends of the sleeve 41. The flexible joint 36 constructed as described permits a limited degree of flexing between the upper end of the rotatable insulator 38 and the shaft 34 to accommodate slight misalignment therebetween.

At its lower end the rotatable insulator 38 has a slip joint that is indicated, generally, at 54 and the details of construction are shown more clearly in FIG. 6. The slip joint 54 includes a sleeve 55 which is secured against rotation by a transverse pin 56 to the upper end of a shaft 57 which extends through and is journaled in a top wall 58, FIG. 1, of a metallic housing 59 that is suitably secured to one side of the base 11. The slip joint 54 also includes a flange 60 that is secured to the lower end of the rotatable insulator 3'8 and is connected by bolts 61 to a mounting flange 62 which is telescoped over the upper end of the sleeve 55. An opening 63, FIG. 7, extends through the lower portion of the mounting flange 62 for receiving the upper end of the sleeve 55. The opening 63 has a flat side to provide non-rotatable engagement with a fiat side 65 of the sleeve 55. A cotter pin 66 extends through the upper end of the shaft 57 to prevent disassembly of the slip joint 54. By employing the slip joint 54 which permits limited relative longitudinal movement between the rotatable insulator 38 and the sleeve 55, it is unnecessary to position the metallic housing 59 with a great deal of precision on the base 11. Also expansion and contraction of the various parts is accommodated through a limited extent by the slip joint 54.

As pointed out the shaft 57 extends into the metallic housing 59. In FIG. 8 it will be observed that a key 70 secures a cam lock 71 to the shaft 57 so that they rotate conjointly. As pointed out above it is desirable to prevent inadvertent rotation of the shaft 57 in order to prevent inadvertent tripping of the current interrupter 17 to the open position. For this purpose a shoulder 72 is formed on the cam lock 71 and is arranged to be engaged by a distal end 73 of an arm 74 which forms a part of an auxiliary latch lever that is indicated, generally, at 75. The auxiliary latch lever 75 is pivoted at 76 on a support 77 which extends inwardly from a side wall 78 of the metallic housing 59. Another arm 79 of the auxiliary latch lever 75 has a slot 80 near its distal end for receiving a transverse pin -81 to make pivotal and sliding connection to a link '82 which is pivotally connected at 83 to an armature 84. An electrically energizable solenoid 85 is arranged to attract the armature 84 for rotating the shaft 57 against the force of a retraction spring '86. The driving connection to the shaft 57 from the link 82 is effected through a driving arm 87 that is freely rotatably mounted on the shaft 57. A lost motion opening '88 is formed in the driving arm '87 for receiving a driving pin 89 that extends inwardly from the cam lock 71.

On energization of the solenoid 85, the armature 84 is attracted so as to move to the right to the position shown in FIG. 9 which is accompanied by rotation of the auxiliary latch lever 75 and movement of the distal end 73 out of the path of the shoulder 72 on the cam lock 71. During this interval the driving arm 87 is rotated through a limited extent to bring the opposite side of the lost motion opening 88 into engagement with the driving pin 89. This lost motion not only provides for movement of the distal end 73 of the arm 74 out of the path of the shoulder 72 but also it permits the armature 74 to accelerate without any load being applied thereto. The continued movement of the armature 84 to the right rotates the driving arm 87 to the position shown in FIG. 10 where the auxiliary latch lever 75 is swung to the position there shown and the shaft 57 has been rotated to the extent indicated.

This rotation of the shaft 57 is accompanied by a corresponding rotation of the rotatable insulator 38 and simi-- lar rotation of the arm 33, FIG. 2, from the position shown by full lines to the position shown by broken lines. Because of the connection provided by the collapsible linkage means 32, the trip lever 28 is rotated from the position shown by full lines to the position shown by broken lines with the result that the plastic nose 25 engages the distal end of the main latch extension 24 and moves it to the unlatched position whereupon the contacts in the current interrupter 17 are opened.

As pointed out above, there is the possibility that the arm 33 might not return to its position shown by full lines in FIG. 2. This might occur because of the armature 84 having been retained in the operated position shown in FIG. 10. Accordingly, it is desirable that provision be made to permit the trip lever 28 to return to the untripped or full line position shown in FIG. 2. It is for this purpose that the collapsible linkage means 32 is provided. It includes a pair of links 92, FIGS. '2, 3 and 4, that are connected by a pivot pin 93 to the distal end of the arm 31 which forms a part of the trip lever 28. Stops 94 on the upper and lower sides of the arm 31 are engaged by the juxtaposed sides of the links 92 to limit their movement in a clockwise direction relative to the arm 31. At their other ends the links 92 are connected by a pivot pin 95 to a pair of links 96 which are positioned between the links 92 and are connected by a pivot pin 97 to the distal end of the arm 33 which rotates with the shaft 34 that is connected by the flexible joint 36 to the rotatable insulator 38. In order to hold the

links

92 and 96 in the overcenter position shown in FIG. 2 and to return them to that position, a coil tension spring 98 is connected at one end to the pivot pin 95 and at the other end to a spring anchor 99 which extends upwardly from the cover 30 of the mechanism housing 16. In FIG. 2 it will be observed that the coil tension spring 98 holds the

links

92 and 96 in such position that the pivot pin 95 is slightly to one side of a line 100 which interconnects the pivot pins 93 and 97. In this position due to the reaction between the links 92 and the stops 94, the

links

92 and 96 function as a compression member between the

pivots

93 and 97 and transmit the rotation of the arm 33 to the arm 31 of the trip lever 28. A coil tension spring 101 interconnects the spring anchor 99 and the arm 31 of the trip lever 28 to return it to the untripped or non-operated position indicated by full lines in FIG. 2.

It is desirable to limit the extent of rotation of the trip lever 28 and of the arm 33. For this purpose, as shown more clearly in FIG. 4, a boss 103 depends from the arm 31 and extends into a cavity 104. In like manner a boss 105 extends from the arm 33 into a cavity 106.

In order to protect the trip lever 28, collapsible linkage means 32 and arm 33 from the Weather, a cover 107 is arranged to overlie them and to .be connected by suitable means to the cover 30.

Flexible shunts

108 and 109 interconnect the cover 30 and the arms 31 and 33 for the purpose of maintaining all of these parts at the same potential.

In describing the operation of the auxiliary trip or independent operating means 23 it will be assumed that the main latch extension 24 occupies the position shown by full lines in FIG. '2 and that the trip lever 28, collapsible linkage 32 and arm 33 occupy the positions similarly shown in this figure. The solenoid 85, FIG. 8, is energized to attract the armature 84. The auxiliary latch lever 75 is rotated in the direction indicated by arrow 111, FIG. 9, to the unlocked position before any movement of the cam lock 71 takes place because of the lost motion provided by the lost motion opening 88 in the driving arm 87 and the driving pin 89 extending thereinto from the cam lock 71. This lost motion permits the armature 84 to accelerate for more readily rotating the insulator 38 and parts rotatable therewith on continued movement of the armature 84 to the position shown in FIG. 10. Because of the stop 94, the

links

92 and 96 function as a compression member and, on rotation of the arm 33 to the position shoyvn by broken lines in FIG. 2, the trip lever 28 is rotated from the position shown by full lines to the position shown by broken lines. As a result of rotation of the arm 31 of the trip lever 28 and due to the reaction between the links 92 and the stops 94, the pivot pin- 95 is moved from one side of the line 100 connecting the

pivots

93 and 97 to the opposite side and to the position shown by 'broken lines in FIG. 2 which corresponds to the broken line position of the arm 27 and the tripped or operated position of the main latch extension 24 shown by broken lines in FIG. 2.

In the event that the retraction spring 86 FIG. 8, Were unable to return the arm 33 to the full line position shown in FIG. 2 but rather it were to remain in the position shown by full lines in FIG. 3, then the spring 101 acts to return the trip lever 28 to the position shown by broken lines in FIG. 3 in which case the linkage means 32 further collapses from its position shown by broken lines in FIG. 2 to the position shown by broken lines in FIG. 3 In this figure the positions of the main latch extension 24, trip lever 28 and arm 33 shown by full lines correspond to the positions of these same parts shown by broken lines in FIG. 2. Now it will be apparent that the main latch extension 24 will be free to reset by the return of the trip lever 28 to the non-operated position by the coil tension spring 101 independently of the movement of the arm 33 and rotatable insulator 38 to the nonoperated position. As a result there is no interference with the subsequent recocking of the spring in the mechanism housing 16 and reclosure of the contacts of the current interrupter 17.

Under normal operating conditions, as soon as the solenoid 85, FIG. 8, is deenergized, the retraction spring 86 returns the armature 84 to the position here shown. The opposite side of the lost motion opening 88 engages the driving pin 89 and through the cam lock 71 the shaft 57 is rotated to the non-operated position with the auxiliary latch lever 75 returned to the latched position shown in FIG. 8. The coil tension spring 98, FIG. 2, acts to return the linkage means 32 from the collapsed position shown in either FIG. 2 or FIG. 3 to the overcenter position shown in FIG. 1.

As pointed out, the lost motion provided by the opening 88 and the driving pin 89 permits the armature 84 to accelerate and move a slight distance before rotating the shaft 57. Thus, an impact is applied to the insulator 38 to accelerate it and the parts rotatable therewith. This impact is transmitted through the collapsible linkage means to the trip lever 28 and the plastic nose 25 which initially is spaced, as indicated at 112 and adjusted by screw 26, from a face 113 of the main latch extension 24. This permits the application of a substantial impact to the main latch extension 24 for moving it to unlatched position.

What is claimed as new is:

1. Switch means comprising:

a current interrupter,

means biasing said current interrupter to open position,

a latch holding said current interrupter closed,

operating means for tripping said latch to open said current interrupter, and

auxiliary trip means operable independently of said operating means to trip said latch including:

a pivoted first arm arranged to trip said latch,

a pivoted second arm arranged to be rotated by independent operating means, and

collapsible linkage means interconnecting the distal ends of said arms for releasing said latch to return to latched position independently of return of said auxiliary trip means to non-operated position.

2. In switch means including a current interrupter biased to open position and held closed by a latch with operating means to trip said latch to open said current interrupter and auxiliary trip means operable independently of said operating means to trip said latch, the improvement wherein said auxiliary trip means includes:

collapsible linkage means for releasing said latch to return to latched position independently of return of said auxiliary trip means to nonoperated position, said collapsible linkage means comprising:

a first link pivoted at one end to the distal end of a first arm arranged to trip said latch,

a second link pivoted at one end to the distal end of a second arm arranged to be rotated by independent operating means,

means pivotally interconnecting the other ends of said links,

stop means on said first arm, and

spring means biasing said first link into engagement with said stop means and said links to a position in which the pivotal connection therebetween lies to one side of a line interconnecting their pivotal connections to said arms and rotation of said second arm causes rotation of said first arm to trip said latch and to shift said links to another position in which said pivotal connection is shifted to the opposite side of said line and said first arm is permitted to return to its non-operated position independently of said second arm.

3. Switch means according to claim 2 wherein said spring means is connected to said means pivotally interconnecting said other ends of said links, and additional spring means bias said first arm to nonoperated position. 4. The switch means according to claim 3 wherein means connect said additional spring means to said first arm.

5. The switch means according to claim 2 wherein stop means individual to each of said arms limit the rotation thereof through predetermined extents.

6. The switch means according to claim 2 wherein said auxiliary trip means also includes auxiliary operating means for releasing said latch by force transmitted through said collapsible linkage means, and

auxiliary latch means prevent operation of said auxiliary trip means until released by energization of said auxiliary operating means.

7. The switch means according to claim 6 wherein said operating means includes a rotatable insulator connected at one end to said collapsible linkage means, and

solenoid operated means connected to the other end of said rotatable insulator.

8. The switch means according to claim 7 wherein said auxiliary latch means includes means to prevent rotation of said rotatable insulator and to be moved to unlatched position on energization of said solenoid operated means.

9. The switch means according to claim 8 wherein lost motion connecting means between said rotatable insulator and said solenoid operated means efiect unlatching of said auxiliarylatch means in advance of the start of rotation of said insulator.

10. The switch means according to claim 7 wherein a. flexible joint interconnects said one end of said rotatable insulator and said collapsible linkage means, and

a slip joint interconnects said other end of said rotatable insulator and said solenoid operated means. 11. In combination: a current interrupter biased to open position, a. latch holding said current interrupter closed, trip means for tripping said latch to open said current interrupter, and auxiliary trip means for tripping said latch including:

a rotatable member, means interconnecting said rotatable member and said latch, a driving arm rotatable on said rotatable member, an armature connected to a distal end of said driving arm, a solenoid for operating said armature to rotate said driving arm, a cam lock secured to said rotatable member adjacent said driving arm, and lost motion connecting means between said driving arm and said cam lock to allow said armature and said driving arm to move initially independently of said cam lock and said rotatable member on energization of said solenoid. 12. The combination according to claim 11 wherein: said cam lock has a shoulder, an auxiliary latch lever is arranged to engage said shoulder and prevent rotation of said rotatable member, and means interconnect said auxiliary latch lever and said armature to move said latch lever out of the path of said shoulder before said cam lock is rotated by said armature.

References Cited UNITED STATES PATENTS 3,116,391 12/1963 Lindell et a1. 200-146 2,881,287 4/1259 Clausing 335--174 XR 1,371,536 3/1 921 Aalborg. 3,106,137 10/1963 MCClOlld 74-520 XR FOREIGN PATENTS 142,860 l/ 1931 Switzerland.

BERNARD A. GILHEANY, Primary Examiner D. M. MORGAN, Assistant Examiner 7 US. 01. X.R.