US2242092A - Switch construction - Google Patents

Description

May 13, 1941. w. o. SCHULTZ 2,242,992

SWITCH CONSTRUCTION Filed April 19, 1939 5 Sheets-Sheet l INVENT OR. W/zz/AM 0. Jam/*1 ATTORNEY.

T May 13, 3941..

w. o. SCHULTZ 2,242,092

SWITCH CONSTRUCTION Filed April 19, 1939 SSheets-Sheet 2 INVENTOR. Wm MM 0. Jmz/zrz ZZZ, /%2J ATTORNEY.

y 13, w. o. SCHULTZ SWITCH CONSTRUCTION Filed April 19, 1939 3 Sheets-Sheet 3 Patented May 13, 1941 SWITCH CONSTRUCTION William O. Schultz,

signor to Line Material South Milwaukee, Wis., as-

Company, South Milwaukee, Wis., a corporation of Delaware Application April 19, 1939, Serial No. 268,662

18 Claims.

This invention relates to a switch construction and is particularly directed to a high voltage switch such as a disconnecting switch, for instance, although the. invention is not limited to this type of switch.

This is an improvement over that disclosed in the patent issued to William O. Schultz and Alwin G. Steinmayer No. 2,149,365 of March 'I, 1939, for Switch constructions, and has the same general objects as those set forth in the patent.

Further objects are to provide a high voltage switch in which tubular arms are provided so as to secure lightness and also so as to avoid as far as possible sharp corners or angular portions, thereby reducing corona losses and radio disturbances, and to so arrange the tubular parts that they constitute a truss formation and provide maximum strength with minimum weight.

Further objects are to provide a switch construction of the above outlined type in which a main switch arm is provided and an auxiliary or movable switch blade is carried adjacent the outer end of the main switch arm and moves upwardly into engagement with stationary contacts, and to provide means for first moving the auxiliary blade or movable blade downwardly out of engagement with the stationary contacts and thereafter moving the main switch arm upwardly, and to provide means for insuring this sequential mode of operation and the reverse sequential mode of operation during closing without the use of latches or other auxiliary mechanism of this type.

Further objects are to provide a construction in which a balancing spring is employed to assist in the opening of the main switch arm for when it is considered that these main switch arms are frequently ten or fifteen feet long, it is appreciated that considerable force is usually necessary, and the invention further contemplates means for housing the main pivotal joint or connection and the balancing spring both when the switch is in closed position and when it is in open position so as to guard against the formation of sleet or ice which might interfere with the operation of the switch.

Further objects are' to provide a switch construction in which the stationary contact is always adequately housed, and in which the auxiliary blade or movable contact and its immediately associated parts are also adequately housed when the switch is in closed position, and to provide a construction such that the mechanism immediately associated with the auxiliary blade is also adequately and fully housed when the switch is in open position to thereby prevent the formation of sleet or ice on the parts, no matter whether the switch is opened or closed.

Further objects are to provide a switch construction in which a considerable force is immediately available directly at the auxiliary switch blade for opening and closing movement without imposing any strain upon the main switch arm during this opening or closing motion of the auxiliary switch blade.

Further objects are to provide a novel construction whereby the auxiliary switch blade is locked in its retracted position with reference to the main blade while the main blade is open,

'' without the use of latches, and to utilize the housing constructions themselves to initiate the closing motion of the auxiliary switch blade, the final closing motion of the auxiliary switch blade being accomplished by the transmission of force through the mechanism itself substantially directly to the auxiliary switch blade.

Further objects are to provide means for insuring the alignment of the auxiliary switch blade with the stationary contacts, irrespective of variations in machining or alignment of other parts of the device, and to provide means for insuring the stopping of the main switch arm at the correct position for the subsequent engagement of the auxiliary switch blade with the stationary contact.

Further objects are to provide a construction which is relatively simple and has a small number of parts, which may be very easily operated and which is cheap to produce.

An embodiment of the invention is shown in I the accompanying drawings, in which:

Figure 1 is a side elevation, partly in section, showing the switch.

Figure 2 is an enlarged detail, partly in section, showing the stationary contact and the movable or auxiliary switch blade and the associated parts,

Figure 3 is a sectional view on the line 33 of Figure 1.

Figure 4 is a sectional view on the line of Figure 1.

Figure 5 is a plan view, partly in section, of the structure shown in Figure 2.

Figure 6 is a view corresponding to Figure 2, showing the auxiliary switch blade in open position just as the main switch arm is beginning to rise.

It is to be understood that though a single switch construction has been shown, that obviously the switches may be arranged in a gang for multiple operation in accordance with the usual practice, and may be simultaneously operated in any suitable manner, for example as shown in the above noted patent.

Referring to the drawings, it will be seen that the switch is carried by a channel or other base I and has stationary insulators 2 and 3 which respectively support the main pivotal portion of the switch and the stationary contact. The switch is also provided with a rotary insulator 4 which is mounted in any suitable manner upon a rotary shaft 5 carried in a suitable bearing 6 secured to the base I,

The switch comprises a main arm 1 which is of tubular construction and which has rigidly secured thereto at its pivotal end a housing 8- as shown in Figures 1 and 3.

This housing, as may be seen from Figure 3, is of approximately rectangular construction at its rear portion and is pivotally mounted on a pivot pin 9 carried by the arms ll) of the main pivot portion H, which latter is carried by the insulator 2. A heavy helical spring I 2 is loosely coiled about the pin 9 and bears at one end against the portion H and at its other end against a stop or lug l3 carried by the housing 8, as shown in Figures 1 and 3. This spring constitutes a balancing spring for partially balancing the weight of the main switch arm and its associated parts.

The tubular main switch arm 7 is flattened adjacent its pivoted end and receives a heavy flexible leader 14 whose. other end is secured to the body of the portion H, such portion ll continuing over and beyond the rotary insulator 4 and terminating in connecting means l5.

It is to be noted that the parts constituting the pivot construction including the balancing spring are housed by the housing 8 whether the switch is opened or closed.

The outer end of the main switch arm carries a casting it which, as may be seen most clearly from Figures 2 and 5, continues upwardly to form an arched support I! which is of channel shape and which has an opening 18 through its rear wall for a purpose hereinafter to appear. Arcing horns l9 are also secured to the casting l6, and diverge outwardly and terminate in outwardly projecting parallel portions, as shown most clearly in Figure 5.

The support !1 pivotally carries the movable housing or sleet hood 20. This sleet hood has a rounded upper portion spaced from and approximately conforming to the support IT, as shown in Figure 2, and the side walls of the hood or housing 26' extend vertically downwardly and are provided with inwardly projecting bosses 2|. Pivot pins 22 extend through these bosses and are screw-threaded to them. These pivot pins are provided with unthreaded ends which fit within hubs23 integral with the support I? as shown in Figure 5,. thereby constituting a pivot for the housing or hood 20.

A movable or auxiliary switch blade 24 is formed integrally with the hood and projects laterally therefrom, as shown in Figures 2 and 6. A pair of flexible leaders 25 are positioned within the rounded hood 20 and have their forward ends secured to the hood and their rear ends secured to the casting I6.

These flexible leaders are positioned on oppo site sides of and out of contact with the support H, as shown in Figure 5, and when the auxiliary switch blade is in closed position, they occupy the curved, substantially circular position shown in Figure 2, and when the auxiliary switch blade is in open position, they occupy a more sharply curved position, as shown in Figure 6, the construction providing a clear space on opposite sides of the support I! for the motion of the flexible leaders from their position shown in Figure 2 to their position shown in Figure 6, without causing any sharp kinks or undue flexing of the flexible leaders.

A tubular operating rod 26 has its outer end pivotally connected to the hood 293 by means of the transversely extending pin 27, see Figures 2 and 5, and a spring 28 extends between the pin 21 to a transverse pin 29 carried by the stationary sup-port i7. Normally the line of pull of this spring is on the forward side of the main pivot pins 22 for the hood but when the auxiliary blade is in open position, the line of pull of the spring is on the other side of the pivot 22, as shown respectively in Figures 2 and 6.

Further as shown in Figure 6, the transverse pin 21 hooks beneath the support H and the support, thereby, constitutes a stop to limit the opening motion of the auxiliary switch blade 24.

The stationary contact consists of a pair of contact blades 36 which have diverging lower ends, as shown in Figure 4, and which are mounted so as to have a floating action within the stationary hood 3i. The contacts 30 are each provided with laterally projecting pins 32 about which a helical spring 33 is coiled, the spring and the projecting pins 32 being socketed within inwardly projecting sockets or bosses 34 mounted within and carried by the stationary hood or housing 31. Preferably the pins 32 are integral with plates 35 which are secured to the contact plates or contacts 33 by riveting or in any other suitable manner.

Flexible leaders 36 join the hood 3! and the contacts 39 and have their inner ends clamped between the plates 35 and the blades 36 and their outer ends clamped between the bases 31 of the sockets 34 and the inner walls of the hood. This construction not only provides good electrical connection between the hood 3! and the contacts 30, but also the flexible leaders 36 being of the usual flat strap like formation tend to hold the blades 39 in correct alignment, the back wall of the hood, however, preventing any material turning or rocking of the blades 30, the blades however being freely carried in a floating manner, as is apparent from Figures 4 and 6.

The back wall of the hood 3! is provided with a recessed portion 38, see Figure 6, which accommodates the projecting end of the auxiliary blade 24 when such blade is in closed position, as shown in Figure 2, and the upper portion of the recess 38 is provided with a shouldered part 39, see Figure 2, which constitutes a stop limiting the closing motion of the auxiliary blade 24.

The hood 3! is provided with an upwardly projecting anvil like fin 66 which is struck by a projection 4! carried by the movable hood or housing 20, as shown in Figure 6, when the movable housing is rocked by the operating arm 26 during opening motion and which thereby gives an initial upward start to the main switch blade.

These projections it) and 4| have a further function of initiating the closing motion of the movable switch blade 24, as is obvious from an inspection of Figure 6, for when the main switch arm is rocked downwardly, the projection 41 engages the projection 49 and suddenly starts the auxiliaryswitch blade 24 towards its initialclos ing stroke and thereby carries the line of pull of the spring 28 across the axis of the pivot 22, the spring and the thrust of the arm 26 both cooperating to provide a quick closing stroke for the auxiliary blade 24 so that such auxiliary blade moves into the position shown in Figure 2.

The hood 3| is provided with integral, outwardly projecting portions or stops 42, see Figure 4, upon which the movable arcing horns l9 rest when the switch is in closed position, thus affording means for limiting the downward rocking motion of the main switch arm. These rocking horns [9 are guided into place by engaging the stationary arcing horns 43 which latter may be slightly curved inwardly towards each other in accordance with the usual practice to constitute guides for the movable arcing horns IS.

The rear end of the operating rod 26 is pivotally supported by a lever 44 pivoted to the housing or hood 8, as shown in Figure l, and pivoted to the fittings 45 and 46 which are attached to the operating arm 26 and to the link 41 respectively. The other end of the link 41 carries a fitting 48 which is pivoted to a fitting 49, the latter in turn being pivotally mounted on the crank arm 50.

The crank arm 50 is rigidly connected to a short shaft extending through the member I l, as shown in Figure 1, and operatively secured to the upper end of the insulator 4 so that when immediately the insulator 4 is rotated by any means, such as that indicated at 52 in Figure 1, the crank arm will be simultaneously rotated to either raise or lower the main switch arm and operate the auxiliary switch blade.

It will be seen from reference to Figure 2 that when the switch is being opened, that the operating member 26 has the maximum leverage for rocking the auxiliary switch blade and that as this rocking motion the spring 28 passes across the center of the pivot 22, see Figure 6, and at about this time the projection 4| engages the projection 40 and gives the main switch arm an upward start which is completed by the pull on the operating arm 26 imparted from the crank 50.

When the auxiliary switch blade has been rocked with reference to the main switch arm into the position shown in Figure 6, it is apparent that further motion is prevented due to the engagement of the pin 21 with the support l1. Thereafter the main switch arm and the auxiliary switch blade rock as a unitary structure upwardly into elevated position which may be either vertical or substantially vertical.

Upon lowering motion it is apparent that no thrust imparted to the operating arm 28 can rotate the auxiliary blade 24 from the locked position shown in Figure 6, as the line of thrust would be above the axis of the pivot 22, see Figure 6. It is not until the housing 20 and the auxiliary switch blade are rocked due to the engagement of the projections 4| and 40 to carry the line of thrust below the axis of the pin 22, that it is possible to cause relative motion between the auxiliary switch blade and the main switch arm. At about the same time the line of pull of the spring 28 also passes across the axis of the pivot 22. As the parts move towards the position shown in Figure 2, it is apparent that maximum leverage is obtained for rocking the auxiliary switch blade into closed position.

Thus it is apparent that the minimum strains are imparted to the switch structure and that continues, the line of pull of 1 tive motion between powerful opening and closing effort is imparted to the auxiliary switch blade. parent that no auxiliary latching means or auxiliary mechanism is required for preventing relathe auxiliary switch blade and the main switch arm except where this relative motion is desired, the parts automatically functioning as hereinabove described to prevent any inadvertent rocking of the auxiliary switch blade except at the desired times.

Further it will be seen that the immediatelyadjacent operating parts for the auxiliary switch blade are housed by the hood 20 when the parts are in closed position, and it is apparent that when the main switch arm is raised to a vertical position that the housing 20 will now house these adjacent operating portions, as the housing is positioned above such operating portions when the main switch arm is in elevated position. Further it will be seen that the main pivot and the balancing spring are also housed both in open and in closed positions.

It will be seen further that the main switch arm is arrested at its downward limit of stroke and properly aligned with the stationary contact so that the auxiliary switch blade is guided into'its proper position as it rocks to closed position.

It will be seen that a simple switch structure has been provided which consists of a small number of parts and which is free from fragile or delicalte mechanism and also which adequately houses the essential parts of the device.

Although this invention has been described in considerable detail, it is to be understood that such description is intended as illustrative rather than limiting, as the invention may be variously embodied and is to be interpreted as claimed.

I claim:

1. A switch comprising a stationary contact, a main switch arm, a switch blade carried adjacent the outer end of said main switch arm for coaction with said stationary contact and pivotally movable about a pivot point on said main switch arm, spring means between said blade and said main switch arm, said spring means being movable to either of two positions on opposite sides of said pivot point, and an operating arm for raising and lowering said main switch arm, said operating arm being operably connected to said blade by non-extensible means at a point which moves to oppos'te sides of dead center for moving said blade to projected position into engagement with said stationary contact or to retracted position out of engagement With said stationary contact.

2. A switch comprising a stationary contact, a main switch arm, a switch blade carried adjacent the outer end of said main switch arm for coaction with said stationary contact and pivotally movable about a pivot point on said main switch arm, spring means between said blade and said main switch arm, said spring means being movable to either of two positions on opposite sides of said pivot point, an operating arm for raising and lowering said main switch arm, said operating arm being operably connected to said blade by non-extensible means for moving said blade to projected position into engagement with said stationary contact or to retracted position out of engagement with said stationary contact, and means independent of said operating arm for rocking said blade to move said spring past said pivot point when said switch is: completing the final-portion of its closing movement.

Further it is ap- '3. A switchjcomprising a stationary contact, a main switch arm, a switch blade carried adjacent the outer end of said main switch arm for coaction with said stationary contact and pivotally movable about a pivot point, an operating arm operatively connected to said blade by non-extensible means for rocking said blade and for raising and lowering said main switch arm, said operating arm being movable from a position on one side of said pivot point, when said blade is in closed position, to a, position on thepther side of said. pivot point, when said blade is in open position, and a spring tending to hold said blade in open position when said blade has beenrocked to openposition.

4. A switch comprising a stationary contact, a

main switch arm, a switch blade carried adjacent the outer end of said main switch arm for coaction with said stationary contact and pivotally movable about a pivot point, an operating arm operatively connected to said blade by non-extensible means for rocking said blade and for raising and lowering said main switch arm, said operating arm being movable from a position on one side of said pivot point, when said blade is in closed position, to a position on the other side of said pivot point, when said blade is in open position, and a spring directly acting on said blade and tending to hold said blade in open position when said blade has been rocked to open position.

5. A switch comprising a stationary contact,- a main switch arm, a blade carried adjacent the outer end of said main, switch arm for coaction with, said stationary contact and movable with respect to said main switch arm, an operating arm operatively connected to said blade for moving said blade and for raising and lowering said main switch arm, a sleet hood carried by said main switch arm, mechanism coacting with said operating arm and housed. by said sleet hood when said main switch arm is in both open and closed positions, and means connected to s-ai operating arm for rocking said sleet hood.

6. A switch comprising a stationary contact, a main switch arm, a combined sleet hood and blade pivotally carried adjacent the outer end of said main switch arm and pivotally movable about a pivot point on said main switch arm,

spring means for holding said blade in open position after said blade has been moved to open position, said spring means being housed by said sleet hood, an operating arm operatively connected to said sleet hood and to said blade for rocking said sleet hood and said blade and for raising and lowering said main switch arm, said operating arm being movable from a position on one side of said pivot point when said blade is inclosed position to a position on the other side of said pivot point when said blade is in open position, said operating arm rocking said sleet hood wth reference to said main switch arm to maintain the housing of said springmeans by said sleet hood.

7. A switch comprising a, stationary contact, a main switch arm, a combined sleet hood and blade arranged with the blade projecting outwardly from said sleet hood, said combined sleet hood and blade being pivotally movable about a pivot point adjacent the outer end of said main switch arm, an operating. arm pivoted within said sleet hood to said combined sleet hood and blade for rocking said sleethood and said blade and for raising and lowering said main, switch arm, and means for locking said blade against 7 connected to said blade and ary sleet hood housing motion when said main switch arm has moved away from said stationary contact.

8. A switch comprising a stationary contact, a main switch arm, a switch blade carried adjacent theouter end of said main switch arm for coaction with said stationary contact and pivotally movable about a pivot point on said main switch arm, spring means between said blade'and said main switch arm, said spring means being movable to either of two positions on opposite sides of said pivot point, an operating arm for raising and lowering said main switch arm, said operating arm being operably connected to saidv blade by non-extensible means for moving said blade to projected position into engagement with said stationary contact; or to retracted position out of v engagement with said stationary contact, and stationary means adapted to be operatively connected to said blade to move said spring past said pivot point when said switch is completing, the

final portion of its closing movement.

9. A switch comprising a stationary contact, a main switch arm, a switch blade pivotally mounted adjacent the outer end of said main switch arm and pivotally movable about the pivot point into and out of engagement with said stationary contact, an operating arm pivotally connected to said blade for raising and lowering said main switch arm and for rocking said blade with reference to said main switch arm, a spring rockable past dead center for holding said blade in open position when said blade has been rocked to open position, said blade having a projecting portion,

and a stationary member for engaging the pro-- jecting portion of said blade for rocking said spring back across dead center.

10-. A switch comprising a stationary contact, a main switch arm, a switch blade pivotally mounted adjacent the outer end of said main switch arm and pivotally movable about the pivotpoint into and out of engagement with said stationary contact, an operating arm pivotally connected to said blade for main switch arm and for rocking said blade with reference to said main switch arm, said operating arm being movable pastdead center with: reference to said pivot point when said bladeis in open position, a stationary member adjacent said stationary contact, and means operatively engaging said stationary member when said switch is completing its closing stroke for rocking said blade towards closed position and for moving said operating arm past dead center.

11. A switch comprising a stationary contact, a main switch arm movable from switch closed position to a position away from said stationary contact, a switch blade and sleet hood assemblypivotally mounted adjacent the outer end of said main switch arm and pivotally movable upwardly about the pivot point into engagement with said stationary contact and pivotally movable downwardly about said pivot point out of engagement with said stationary contact, a stationsaid stationary contact and having an open bottom through which said movable switch blade is adapted to enter and leave, an operating arm pivotally connected to said blade and said first mentioned sleet hood for j rocking said first mentioned sleet hood and blade one side of dead center when said switch blade,

raising and lowering said engages said stationary contact to a position on the other side of dead center when said switch blade is moved to open position, and spring means tending to hold said operating arm on said other side of dead center.

12. A switch comprising a stationary contact, a main switch arm movable from switch closed position to a position away from said stationary contact, a switch blade and sleet hood assembly pivotally mounted adjacent the outer end of said main switch arm and pivotally movable upwardly about the pivot point into engagement with said stationary contact and pivotally movable downwardly about said pivot point out of engagement with said stationary contact, a stationary sleet hood housing said stationary contact and having an open bottom through which said movable switch blade is adapted to enter and leave, an operating arm pivotally connected to said blade and said first mentioned sleet hood for rocking said first mentioned sleet hood and blade and for raising and lowering said main switch arm, said operating arm having pivotal connection with the combined sleet hood and switch blade assembly and movable from a position on one side of dead center when said switch blade engages said stationary contact to a position on the other side of dead center when said switch blade is moved to open position, spring means tending to hold said operating arm on said other side of dead center, and means carried by said stationary sleet hood for rocking the combined sleet hood and switch blade while said switch is completing its closing movement.

13. A switch comprising a stationary contact, a main switch arm, a switch blade pivotally mounted adjacent the outer end of said main switch arm and pivotally movable about the pivot point upwardly into engagement with said stationary contact and downwardly out of engagement with said stationary contact, an operating arm pivotally connected to said switch blade for rocking said switch blade and for raising and lowering said main switch arm, a stationary member adjacent said stationary contact, and means operatively connected to said switch blade and normally out of contact with said stationary member for engaging said stationary member to initiate the opening motion of said main switch arm when said switch blade is being moved away from said stationary contact.

14. A switch comprising a stationary contact, a stationary sleet hood over said stationary contact and having an open lower portion, a main switch arm, a combined switch blade and movable sleet hood pivotally mounted about a pivot point adjacent the outer end of said main switch arm, and an operating arm pivotally connected to said combined movable sleet hood and switch blade for rocking said switch blade into and out of engagement with the stationary contact and for rocking said movable sleet hood, said movable sleet hood having a projecting portion, said switch including a stationary portion engaged by the projecting portion of said movable sleet hood when said switch is completing its closing movement for assisting in the rocking of said switch blade towards switch closed position,

15. A switch comprising a stationary contact,

a main switch arm, a switch blade pivoted about a pivot point adjacent the outer end of said main switch arm, a movable sleet hood pivoted with reference to said main switch arm and located adjacent the outer end thereof, an operating arm operatively and pivotally connected to said switch blade, and a spring housed within said sleet hood for holding said switch blade in open position after said switch arm has been moved to open position.

16. A switch comprising a stationary contact, a main switch arm, a movable sleet hood and switch blade formed as a unitary structure and pivoted adjacent the outer end of said main switch arm and movable about the pivot point with reference to said main switch arm, a spring housed within said movable sleet hood and having a line of pull on one side of said pivot point when the switch is in closed position and having its line of pull on the other side of said pivot point when said switch is in open position, and an operating arm pivotally connected tosaid switch blade and having a line of thrust that passes across dead center with reference to said pivot point, said operating arm being effective to raise and lower said main switch arm and to move said switch blade to open and closed position.

17. A switch comprising a stationary contact, a main switch arm, an arched support carried adjacent the outer end of said main switch arm, a combined sleet hood and switch blade pivoted on said arched support and adapted to rock about the pivot point with reference to said arched support, an operating arm passing through said arched support and pivoted to said combined sleet hood and switch blade and having a line of thrust that passes from one side of dead center when said switch is closed to the other side of dead center when said switch is open with reference to said pivot point, stop means operatively connected to said operating arm for engaging said arched support to arrest the opening motion of said switch blade, and a spring tending to hold said stop in engagement with said arched support when said stop has been moved into engagement with said arched support, said sleet hood housing said arched support and said spring.

18. A switch comprising a stationary contact, a main switch arm having a pivoted end, pivot means supporting said pivoted end, said main switch arm having an outer end adjacent said stationary contact, a switch blade pivotally mounted adjacent the outer end of said main switch arm and pivotally movable about the pivot point on said main switch arm into and out of engagement with said stationary contact, an operating arm pivotally connected to said blade for raising and lowering said main switch arm and for rocking said blade with reference to said main switch arm, a balancing spring at the pivoted end of said main switch arm, and housing means carried by said main switch arm for housing the pivoted end thereof and the said balancing spring, said housing having portions on opposite sides of said spring and each portion constituting part of the pivot means.

WILLIAM O. SCHULTZ.

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