US2599272A - Fast-acting switching device - Google Patents

Description

June 3, 1952 S. MINNECI ET AL FAST-ACTING SWITCHING DEVICE Filed Jan. 2'7, 1951 Inventor's; Salvatore Minneci James F FlcKen'ney Emil J. DeNoyer's Their" Attorney Patented June 3, 1952 FAST-ACTING SWITCHING DEVICE Salvatore Minneci, James F. McKenney, and Emil J. De Noyers, 'Pittsfield, Mass, assignors to General Electric Company, a corporation of New'York Application January 27, 1951, Serial No. 208,178

13 Claims.

This invention relates to switch operating mechanisms, and more particularly to a switch operating mechanism operated by a snap-acting toggle mechanism.

In the operation of electrical switching devices, .it is frequently desirable that the switching device be operated with a fast snap action in order to make and break the circuit speedily and thereby avoid any dangerous arcing effects. For example, when the-switching device is to be used for switching capacitors on and 01f of a power transmission line, it is particularly desirable that the-operating mechanism for the switch be fast acting.

It .is an object of this invention to provide an improved fast acting switch operating mechanism of the toggle type.

It is a further objectof this invention to provide an improved toggle type switch having a fast snap action in either 'a clockwise or a counterclockwise direction.

In accomplishment of these objectives this invention provides a novel toggle mechanism for operating a switch which is double-acting in that it is tripped in both the switch-open position and in the switch-closed position.

The features of our invention which we believe to be novel are set .forth with particularity in the appended claims. Our invention itself, however, both as toits organization :and use, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawing in which Fig. 1 represents a switching device incorporating the toggle mechanism of our invention, vFig. 2 is a detailed view showing the toggle mechanism .of our invention ready to trip in a counterclockwise direction. Fig. 3 shows the position assumed by the toggle mechanism which has been tripped in a counterclockwise direction; Fig. 4 represents the toggle mechanism ready to tripin a clockwise direction; while Fig. 5 represents the position assumed by the toggle mechanism which has been tripped in a clockwise direction.

Referring now to Fig. .1, there is shown a switch operating device having an operating shaft upon Which are mounted contact blades 2 which cooperate with fixed contacts 3. Contacts 2 are rigidly attached to the shaft I and rotate therewith. While we have shown switch blades 2 and contacts 3 for simplicity'of illustration, obviously various other types of switch devices could be operated by the shaft I 'Coaxially positioned about shaft l but not attached thereto in a rigid manner is a hub assembly comprising a disk plate 4, and a worm wheel 5 which are connected together rigidly with respect to each other by a hub member 6 through which the shaft 1 passes. The disk 4, th worm wheel 5 and the hub member 6 may be rotated as a unit independently of shaft 1 since these members are only loosely mounted on shaft l. We provide means for rotating worm wheel 5., hub 6, and disk 4 comprising a motor I having a pinion 8 mounted onshaft 9, pinion 8 cooperating with a gear It mounted on the same shaft as a worm gear which meshes with worm wheel '5. Thus, rotation of motor "I .is communicated through gears 8, l0, and II to gear 5 and thence through hub B to disk 4.

Rigidly attached to shaft l and on th opposite side of disk 4 as compared to the position of hub 6, is a crank member 12. Thecrank 12 is attached intermediate of its length to shaft 1 and has one of its ends projecting much further vradially outwardly of shaft 1 than the other end, thus providing crank l2 with a long and a short lever arm. A spring [3 is attached at point I! to the radially outer end of crank member 12 which is closest to shaft 1, the outer end of the spring being pivotally attached at point 20 to the outer periphery of disk 4. The opposite radially outer end of the crank 12 is pivotally connected at l6 to a bell-shaped toggle lever l4 at substantially the center of gravity of the toggle lever. The outer end of the toggle lever l4, that is, the end opposite its base portion, is pivotally connected at I] to a stop arm 15 lying in a plane parallel to the surface of disk 4. The radially outer end of stop arm 1'5 is pivotally attached at point 22 to some rigidsurface lying radially outwardly of the periphery of disk 4. The stop arm 15, as will be explained more fully hereinafter, also serves as a positive stop to accurately limit the switch movement by blocking the movement of crank member I 22. The radially inner end of stop arm l5 projects slightly radially inwardly-of the outer periphery of disk 4,-and it is to this inwardly positioned end of arm l-5 that the bell-shaped toggle lever is pivotally connected at I?! Attached to the "same surface of disk 4 as that facing spring I 3 and the crank 112 are two projecting -pin members I8 and I9 spaced apart from one another, in the illustrated embodiment of our invention, by approximately degrees of the circumference of the disk 4. .As Will be explained hereinafter, the pin I8 is the trip pin for counterclockwise operation while the pin I9 is the trip pin for clockwise operation.

The operation of our toggle mechanism can .be most clearly understood by reference to 2 through 5, inclusive, which show the toggle mechanism in its various operating positions.

Referring now to Fig. 2, there is shown a representation of our toggle mechanism when it is about to be tripped in a counterclockwise direction. The motor I has rotated the disk 4 through the :gears 8, It, .11, and 5, as shown inFig. i1,to a position such that the counterclockwise trip :pin [8 has just begun to abut against the bell-shaped toggle lever I4. The counterclockwise rotation of the disk 4 has placed the spring I3 under tension, due to the fact that the connection point 20 to which one end of spring I3 is attached on the outer periphery of disk 4 has rotated considerably in the counterclockwise direction, while the connection point 2I of the opposite end of spring I3 has remained fixed. In the position of the various toggle elements as shown in Fig. 2, the crank 12 is prevented from moving due to the fact that the radially innermost end of stop arm I5, adjacent pivot point II, abuts against the edge of crank member I2 and limits the distance which pivot point I! can move inwardly toward the center of disk 4. In this position, pivot point I! is over-center of the straight line connecting pivot points It and 22. The abutting relation between the end of stop arm and the edge of crank member I2 serves as a positive stop to accurately limit the switch movement. As soon as the trip pin I8 begins to bear against the base surface of the bellshaped toggle lever I4, the toggle lever I4 is caused to pivot in a clockwise direction about its pivot point I6, with the result that the pivot point I! moves outwardly toward and crosses over the line connecting pivot points 22 and I6. When this happens, the toggle is broken and the spring I3 immediately pulls crank I2 in a counterclockwise direction to the position shown in Fig. 3. In moving in a counterclockwise direction as just described, the crank I2 rotates the shaft I in a counterclockwise direction due to the fact that crank I2 is rigidly attached to shaft I, and thereb'ycauses an actuation of the switch members 2. The position occupied by the various toggle members after the pivot point I! has crossed the straight line connecting pivot points l6 and 22 and spring l3 has rotated crank I2 in a counterclockwise direction, is shown in Fig. 3. As will be seen, stop arm I5 comes to rest in a position where its edge bears against the edge of crank member I2.

There is shown in Fig. 4 a representation of the toggle mechanism at the instant when the crank arm I2 isabout to be snapped in a clockwise direction. The disk 4 has been rotated by the motor I in a clockwise direction to a point where the clockwise trip pin I9 has just begun to abut the base of bell-shaped toggle lever I4.

The spring I3 has been rotated in a clockwise direction and has been put under considerable tension; however, in the view shown in Fig. 4, the crank I2 and the bell-shaped toggle lever I4 are still in the tripped position to which they have been actuated as shown in Fig. 3. The crank I2 is unable to move to a position which will relieve the tension on spring I3 due to the fact that when the toggle members are in the position shown in Fig. 4 the pivot point I! is over center of the straight line connecting pivot points I5 and 22, and the edge of stop arm I5 is locked in abutting position against the edge of crank I2. However, when trip pin I9 begins to abut against bell-shaped toggle lever I4, it causes toggle lever I4 to pivot in a counterclockwise direction, and in so doing, the pivot point I! moves toward and past the straight line connecting pivot points It and 22. This causes the toggle to trip and crank I2 is pulled around suddenly in a clockwise direction by spring I 3. This causes a rotation of shaft I since crank I2 is rigidly connected thereto, with a consequent clockwise rotation of the switch blades 2 which are rigidly connected to shaft I. There is shown in Fig. 5 th position which the .various elements of the toggle mechanism assume after the switch hassnapped in a clockwise direction. It will be noted that in this position the pivot point I! is again over center of the straight line connecting pivot points I6 and 22, and a counterclockwise motion of the crank I2 cannot occur again until the conditions shown in Fig. 2 have again occurred.

Suitable limit switches may be used to prevent over-travel of motor 1 in either direction beyond the points necessary for the respective trip pins I8 and I9 to actuate toggle lever I4, as hereinbefore described.

The outer periphery of disk 4 is provided along part of its circumference with a raised arcuateshaped cam surface 23 to aid in maintaining pivot point I! in its overcenter position. Cam surface 23 abuts against a pin at pivot point I! projecting below the lower surface of toggle lever I4, with respect to the view shown in the drawing. During the clockwise motion of disk 4 from the position shown in Fig. 3 to that shown in Fig. 4, the cam surface 23 engages the pin projecting from pivot point I! and forces it in an overcenter direction until point 20, the connection point of thespring I3 to the outer periphery of disk 4, has crossed the line connecting point I6, the center of shaft I, and point 2I. After point 20 has moved past the line just mentioned, the direction of the spring force acting on crank member I2 and shaft I reverses and tends to maintain the point I! over center without the aid of cam surface 23. Similarly, in moving in a counterclockwise direction from the position shown in Fig. 5 to that shown in Fig. 2, the cam surface 23 bears against the pin extending from pivot point I! and forces it into the overcenter position until point 20 has crossed the line connecting point IS, the center of shaft I, and point 2I. After point 2!] has crossed, the line just mentioned, the direction of the spring force acting on crank member I2 and shaft I reverses and tends to maintain the pivot point over center without the aid of cam surface 23.

It can be seen that we have provided an improved switch operating mechanism which provides a snap action in both a clockwise and a counterclockwise direction and is suitable for use with heavy duty equipment requiring a powerful snapping action.

While there has been shown and described a particular embodiment of our invention,'it will be obvious to those skilled in the art that various changes and modifications can be made therein without departing from the invention and, therefore, it is aimed in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. A snap acting device comprising a shaft rotatable in a clockwise and a counterclockwise direction, said device having an actuated position corresponding to each of said directions of rotation of said shaft, a hub assembly loosely mountedcoaxially on said shaft, means for rotating said hub assembly, a crank member rigidly attached to said shaft adjacent said hub assembly, said crank member having a long arm and a short arm extending in opposite directions, a spring member attached to the outer end of the shortarm of said crank member, the opposite end of said spring member being attached to a radially outer portion of said hub assembly, a toggle lever pivotally connected to the outer end of the long arm of said crank member, 'a stop to said toggle lever at the second pivot point of said toggle lever, said second pivot point of said toggle lever normally being overcenter of the straight line connecting the fixed pivot point of said stop arm and the first pivot point of said toggle lever, said second pivot point of said toggle lever having an overcenter position corresponding to each of said actuated positions of said device, said stop arm being engageable with said crank member in each of said overcenter positions, tripping means attached to said hub assembly and engageable with said toggle lever for moving said toggle lever out of its overcenter position, and cam means extending along a portion of the outer periphery of said hub member for frictionally biasing said toggle lever so as to maintain said second pivot point in its overcenter position when the position of said spring member is such that it tends to move said second pivot point from said overcenter position prior to the engagement of said trip means to move said toggle lever out of said overcenter position.

6. A snap acting device comprising a rotatable shaft, a hub assembly loosely mounted coaxially on said shaft, a crank member rigidly mounted on said shaft adjacent said hub assembly, said crank member having a long arm and a short arm extending in opposite directions, a spring member attached to the outer end of the short arm of said crank member, the opposite end of said spring member being attached to a radially outer portion of said hub assembly, a toggle member having two pivot points, said toggle member being pivotally attached at its first pivot point to the outer end of the long arm of said crank member, a stop arm attached at one of its ends to a fixed pivot point lying radially outwardly of said hub assembly, the opposite end of said stop arm being pivotally attachedto said toggle member at the second pivot point of said toggle member, i

said second pivot point-normally lying overcenter of the straight line connecting the fixed pivot point of said stop arm and said first pivot point, and means for selectively initiating the rotation of said shaft with a snap action in either a clockwise or counterclockwise direction comprising separate trip means for clockwise and counterclockwise rotation mounted on said hub assembly, said trip means being engageable with said toggle member for moving said toggle member out of its overcenter position.

'7. A snap acting device comprising a rotatable shaft, a hub assembly loosely mounted coaxially on said shaft, a crank member rigidly mounted on said shaft adjacent said hub assembly, said crank member having a long arm and a short arm extending in opposite directions, a spring member attached to the outer end of the short arm of said crank member, the opposite end of said spring member being attached to a radially outer portion of said hub assembly, means for rotating said hub assembly to charge said spring member, a toggle member having two pivot points, said toggle member being pivotally attached at its first pivot point to the outer end of the long arm of said crank member, a stop arm attached at one of its ends to a fixed pivot point lying radially outwardly of said hub assembly, the opposite end of said stop arm being pivotally attached to said toggle member at the second pivot point of said toggle member, said second pivot point normally lying overcenter of the straight line connecting the fixed pivot point of said stop arm and said first pivot point, and means for discharging said spring by selectively initiating the rotation of said shaft with a snap action in either a clockwise or counterclockwise direction comprising separate trip means for clockwise and counterclockwise rotation mounted on said hub assembly, said trip means being engageable with said toggle member for moving said toggle member out of its overcenter position. 7

8. A snap acting device comprising a rotatable shaft, a hub assembly loosely mounted coaxially on said shaft, a crank member rigidly mounted on said shaft adjacent said hub assembly, said crank member having a long arm and a short arm extending in opposite directions, a spring member attached to the outer end of the short arm of said crank member, the opposite end of said spring member being attached to a radially outer portion of said hub assembly, means for rotating said hub assembly to charge said spring member, a toggle member having two pivot points, said toggle member being pivotally attached at its first pivot point to the outer end of the long arm of said crank member, a stop arm attached at one of its ends to a fixed pivot point lying radially outwardly of said hub assembly, the opposite end of said stop arm being pivotally attached to said toggle member at the second pivot point of said toggle member, said second pivot point normally lying overcenter of the straight line connecting the fixed pivot point of said stop arm and said first pivot point, and means for discharging said spring by selectively initiating the rotation of said shaft with a snap action in either a clockwise or counterclockwise direction comprising separate trip means for clockwise and counterclockwise rotation mounted on said hub assembly, said trip means being engageable with said toggle member for moving said toggle member out of its overcenter position, said stop arm and the long arm of said crank member each having one of their respective edges in abutting and locking relation to the other when said second pivot point is in said overcenter position.

9. A snap acting device comprising a rotatable shaft, a hub assembly loosely mounted coaxially on said shaft, said shaft and said hub assembly each being rotatable in both a clockwise and a counterclockwise direction, a crank member rigidly mounted on said shaft adjacent said hub assembly, said crank member having a long arm and a short arm extending in opposite directions, a spring member attached to the outer end of the short arm of said crank member, the 0pposite end of said spring member being attached to a radially outer portion of said hub assembly, means for rotating said hub assembly to charge said spring member, a toggle member having two pivot points, said toggle member being pivotally attached at its first pivot point to the outer end of the long arm of said crank member, a stop arm attached at one of its ends to a fixed pivot point lying radially outwardly of said hub assembly, the opposite end of said stop arm being pivotally attached to said toggle member at the second pivot point of said toggle member, said toggle member having a tripped position corresponding to each of the two directions of rotation of said hub assembly, said second pivot point lying overcenter of the straight line connecting the fixed pivot point of said stop arm and said first pivot point in both of said tripped positions of said toggle member, said first pivot point lying intermediate said fixed pivot point of said stop arm and said second pivot point in one of the overcenter positions of said second pivot point, said second pivot point lying intermediate said fixed pivot point of said stop arm and said first pivot point in the other overcenter position of said second pivot point.

10. A snap acting device comprising a rotatable shaft, a crank member rigidly mounted on said shaft, said crank member having a long arm and a short arm extending in opposite directions, a spring member attached to the outer end of the short arm of said crank member, a toggle member having two pivot points, said toggle member being pivotally attached at its first pivot point to the outer end of the long arm of said crank member, a stop arm attached at one of its ends to a fixed pivot point lying radially outwardly of said shaft, the opposite end of said stop arm being pivotally attached to said toggle member at the second pivot point of said toggle member, means for charging said spring member, and means for discharging said spring member by selectively initiating the rotation of said shaft with a snap action in either a clockwise or counterclockwise direction comprising separate trip means for clockwise and counterclockwise rotation of said shaft, said trip means being engageable with said toggle member.

11. A snap acting device comprising a rotatable shaft, a crank member rigidly mounted on said shaft, said crank member having a long arm and a short arm extending in opposite directions, a spring member attached to the outer end of the short arm of said crank member, a toggle member having two pivot points, said toggle member being pivotally attached at its first pivot point to the outer end of the long arm of said crank member, a stop arm attached at one of its ends to a fixed pivot point lying radially outwardly of said shaft, the opposite end of said stop arm being pivotally attached to said toggle member at the second pivot point of said toggle member, said toggle member having a tripped position corresponding to each direction of rotation of said shaft, said second pivot point lying overcenter of the straight line connecting the fixed pivot point of said stop arm and said first pivot point in each of said tripped positions of said toggle member, separate trip means for selectively initiating the rotation of said shaft with a snap action in either a clockwise or counterclockwise direction, said trip means being engageable with said toggle member for moving said toggle member out of its overcenter position, said first pivot point lying intermediate said fixed pivot point of said stop arm and said second pivot point in one of the overcenter positions of said toggle member, said second pivot point lying intermediate said fixed pivot point of said stop arm and said first pivot point in the other overcenter position of said toggle member, said stop arm and the long arm of said crank member each having one of their respective edges in abutting and locking relation to the other when said toggle member is in either of said overcenter positions. 1

12. A snap acting device comprising a shaft rotatable in both a clockwise and a counterclockwise direction, said device having an actuated position corresponding to each of said directions of rotation of said shaft, a hub assembly mounted adjacent said shaft and axially aligned therewith, said hub assembly being rotatable with respect to said shaft, means for rotating said hub assembly, a crank member rigidly attached intermediate its length to said shaft adjacent said hub assembly, a spring member attached to said 10 crank member at a point radially displaced from said shaft, the opposite end of said spring member being attached to said hub assembly, a toggle lever pivotally connected to said crank member at a point on said crank member which is radially displaced from said shaft in a direction opposite to the point of connection of said spring member, a stop arm having one end connected to a fixed pivot point adjacent said hub assembly, the opposite end of said stop arm being pivotally connected to said toggle lever, the point of pivotal connection between said toggle lever and said stop arm normally being overcenter of the straight line connecting the fixed pivot point of said stop arm and the pivotal connection between said crank member and said toggle lever, said point of pivotal connection between said toggle lever and said stop arm having a different overcenter position corresponding to each of said actuated positions of said device, said stop arm engaging a difierent edge of said crank member in each of said overcenter positions, and tripping means mounted on said hub assembly and engageable with said toggle lever for moving said toggle lever out of said overcenter positions.

13. A snap acting device comprising a shaft rotatable in both a clockwise and a counterclockwise direction, said device having an actuated position corresponding to each of said directions of rotation of said shaft, a hub assembly mounted adjacent said shaft in axial alignment therewith, said hub assembly being rotatable with respect to said shaft, means for rotating said hub assembly, a crank member rigidly attached intermediate of its length to said shaft adjacent said hub assembly, a spring member attached to said crank member at a point radially displaced from said shaft, the opposite end of said spring member being attached to said hub assembly, a toggle lever having a first and a second pivot point, said toggle lever being pivotally connected at its first pivot point to said crank member at a position radially displaced from said shaft in an opposite direction to the point of connection of said spring member to said crank member, a stop arm having one end connected to a fixed pivot point adjacent said hub assembly, the opposite end of said stop arm being pivotally connected to said toggle lever at said second pivot point of said toggle lever, said second pivot point of said toggle lever normally being overcenter of the straight line connecting said fixed pivot point of said stop arm and said first pivot point of said toggle lever, said second pivot point having an overcenter position corresponding to each of said actuated positions of said device, said stop arm engaging a different edge of said crank member in each of said overcenter positions, and tripping means mounted on said hub assembly and engageable with said toggle lever for moving said toggle lever out of said overcenter positions.

SALVATORE MINNECI.

JAMES F. MCKENNEY.

EMIL J. DE NOYERS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,760,547 Fisher May 27, 1930 2,534,007 Dietrich Dec. 12, 1950

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